Showing posts with label PPAR. Show all posts
Showing posts with label PPAR. Show all posts

Friday, October 11, 2013

Conjugated Linoleic Acids: What's the Difference Between cis-9,11 and trans-10,12 CLA and Should We Label Them as "Transfats"? Plus: What Makes CLA Potentially Harmful?

If Hayden Panettiere drinks it dairy can't be bad - despite (or because?) CLA, right? Well, what if I told you that Mrs. Panettiere was advertising milk in the "Got Milk" campaign despite being lactose intolerant?
As a SuppVersity veteran you will be familiar with the idea that trans-10, trans-12 conjugated linoleic acid is the "fat burning" CLA isomer, while 9 cis,11 trans linoleic acid appears to blunt some of the pro-inflammatory actions of its cousin and has been shown to have specific physiological effects on it's own (e.g. increased bone health, cf. Platt. 2009; anti-cancer, cf. Corl. 2003).

As I already mentioned, this is probably nothing new for you, if you make sure to get your daily dose of SuppVersity wisdom everyday. What you may however not be aware of is the fact that researchers like Ye Wang and Spencer D. Proctor are - despite the never-ending hoopla around potential weight loss effects of CLA - still contemplating, whether CLA could not pose a major health threat to all or at least certain subgroups of the population and whether this should or shouldn't be reason enough to change the current food labeling practices.

Do we have to label CLA as "transfat"?

From a technical perspective the above question is obsolete. CLAs are transfats and would thus (technically, again) have to be labeled as such on the product label. From a health perspective, however, things do in fact look different. Due to the fact that the aforementioned ruminant (=naturally produced in the stomach(s) of ruminents) trans-fats have been associated with health benefits (Gebauer. 2011), we could effectively risk to scare consumers away from healthy foods if they were listed as part of the "transfat" category on the product labels.
What's actually the reason that one the same CLA isomer that will have you lose body fat will also "inflame" you? Due to the fact that most of the research on "fat loss supplements" is conducted in sick, obese individuals, people tend to get the false impression that "fat burners" were anti-inflammatory and that anti-inflammatory agents would burn fat.

Effects of 10-trans,12 CLA on fatty acids & glucose metabolism and IL-6 gene expression in isolated fat cells in the petri dish (Hartwig. 2013)
Now, while it is correct that soothing inflammation will help the future Mr. Average Joe, who is going to be an obese (pre-)diabetic, lose weight, this has little to do with any active contribution to the oxidation of body fat. 10-trans,12 CLA, on the other hand, has been shown to block lipid storage, increase mitochondrial uncoupling (UCP-2), lower PPAR-alpha and ramp up the oxidation and release of fatty acids from the fat stores (Hartig. 2013). Unfortunately it will also block the uptake of glucose and increase the expression of the pro-inflammatory cytokine IL-6 in fat cells. So, if you took 10-trans,12 CLA at very high doses it will probably in fact keep you lean.

If you cannot handle the sudden increase in free fatty acids, pack the glucose into your liver and muscle glycogen stores and deal with the exuberant amount of inflammatory cytokines, however, it will only make you sick.
Currently, the trans-fat content on many food labels (and in legislative documents) does not include ruminant CLA isomers and Wang and Procter acknowledge that:
"As highlighted in a recent quantitative review of prospective cohort studies by Bendsen et al. dietary consumption of ruminanttrans-fat may be protective against total as well as fatal CHD events." (Wang. 2013)
The researchers do however point out that concerns about potential adverse effect on atherogenic cholesterol profiles from supplemental CLA are not unwarranted - at least if they are used by a group of persons - abdominally obese and/or insulin resistant men, for example (Riserus. 2002 a,b).

Australia and New Zealand suggest a re-evaluation

Accordingly, Australia and New Zealand (FSANZ) proposed to re-evaluate their perception regarding the exclusion of CLA from the TFA definition on nutrition labels.

If you re-evaluate something, you do not necessarily have to change them and if you go through the concise summary of results Wang and Procter present in their paper (see table 1 for an overview of the currently published meta-analyses, it does not appear necessary to question the current practice to label only industrually produced trans fats.

Table 1: Meta analysis with beneficial (green), neutral (grey) and potentially negative outcome (red); based on Wang & Proctor (2013)
As the authors point out, the inclusion of CLA in the total amount of transfats on the label would only drive people away from the consumption of whole food products. This is particularly true in view of the fact that the ill-health effects of "trans-fats" are something everyone will have heard about. The fact that these ill health effects are not to be expected from trans fats in dairy and other CLA containing whole foods, on the other hand, is still news to many costumers.

Moreover, how would you, me and everyone else who may well be aware that CLAs are not the bad guys and the "trans-fat" in grass fat butter is not going to hurt us know if the 3g of transfats in another product we buy are actually from the undisclosed amount of butter (and thus CLA) in it? It could likewise be that the producer added a little extra partially hydrogenated vegetable oil to cut the product costs and neither you nor me would know that.
Suggested read: "A Higher Intake of CLA and Vaccenic Acid from Dairy, Beef, Veal and Lamp Could Prevent Subtle Weight Gain" | read more
Only the obese have to be worried: Based on the currently available evidence the healthy and lean person (hopefully you) has absolutely no reason to avoid products with a "high" natural CLA content and thus both the pro- (trans-10,12) and (partly) anti-inflammatory (cis-9,11) form of CLA in them.

For obese and insulin resistant individuals things do however look somewhat different. A 2004 study by Risérus et al., for example, has been able to show that even the allegedly "harmless", 9 cis,11 trans linoleic acid can worsen both lipid peroxidation and insulin resistance in 25 abdominally obese men. (Risérus. 2004).

With 3g/day the dosage that was used in the Risérus study, the amount of CLA was yet much hither than the amount of CLA you can possibly ingest with nourishing foods such as butter, full-fat dairy, grass-fed beef (and beef in general, by the way). Instead of these you are thus better advised to avoid CLA supplements... but don't worry if you take another look at the data in table 1 you will have to concede that they are pretty much useless, anyway.
Reference:
  • Corl BA, Barbano DM, Bauman DE, Ip C. cis-9, trans-11 CLA derived endogenously from trans-11 18:1 reduces cancer risk in rats. J Nutr. 2003 Sep;133(9):2893-900.
  • Gebauer SK, Chardigny JM, Jakobsen MU, et al. Effects of ruminanttrans fatty acids on cardiovascular disease and cancer: a comprehensive review of epidemiological, clinical, and mechanistic studies.Adv Nutr. 2011; 2, 332 – 354.
  • den Hartigh LJ, Han CY, Wang S, Omer M, Chait A. 10E,12Z-conjugated linoleic acid impairs adipocyte triglyceride storage by enhancing fatty acid oxidation, lipolysis, and mitochondrial reactive oxygen species. J Lipid Res. 2013 Nov;54(11):2964-2978. 
  • Lenz TL & Hamilton WR. Supplemental products used for weight loss. J Am Pharm Assoc. 2004; 44,  59– 67, quiz 67– 58.
  • Onakpoya IJ, Posadzki PP, Watson LK, Davies LA, Ernst E. The efficacy of long-term conjugated linoleic acid (CLA) supplementation on body composition in overweight and obese individuals: a systematic review and meta-analysis of randomized clinical trials. Eur J Nutr. 2012 Mar;51(2):127-34.
  • Platt I, El-Sohemy A. Effects of 9cis,11trans and 10trans,12cis CLA on osteoclast formation and activity from human CD14+ monocytes. Lipids Health Dis. 2009 Apr 29;8:15.
  • Risérus U, Arner P, Brismar K, Vessby B. Treatment with dietary trans10cis12 conjugated linoleic acid causes isomer-specific insulin resistance in obese men with the metabolic syndrome. Diabetes Care. 2002 Sep;25(9):1516-21.
  • Risérus U, Basu S, Jovinge S, Fredrikson GN, Arnlöv J, Vessby B. Supplementation with conjugated linoleic acid causes isomer-dependent oxidative stress and elevated C-reactive protein: a potential link to fatty acid-induced insulin resistance. Circulation. 2002 Oct 8;106(15):1925-9
  • Salas-Salvadó J, Márquez-Sandoval F, Bulló M. Conjugated linoleic acid intake in humans: a systematic review focusing on its effect on body composition, glucose, and lipid metabolism. Crit Rev Food Sci Nutr. 2006;46(6):479-88. Review.
  • Schoeller DA, Watras AC, Whigham LD. A meta-analysis of the effects of conjugated linoleic acid on fat-free mass in humans. Appl Physiol Nutr Metab. 2009 Oct;34(5):975-8.
  • Tricon S, Yaqoob P. Conjugated linoleic acid and human health: a critical evaluation of the evidence. Curr Opin Clin Nutr Metab Care. 2006 Mar;9(2):105-10. Review.
  • Whigham LD, Watras AC, Schoeller DA. Efficacy of conjugated linoleic acid for reducing fat mass: a meta-analysis in humans. Am J Clin Nutr. 2007 May;85(5):1203-11.

Sunday, October 6, 2013

Maintain & Increase Your Insulin Sensitivity - Wrap-Up: Overview + 3 Stacks. Plus: AMPK & PPAR-γ Revisited

It's not about exercise or nutrition, it's about both of them. And as long as it is not about the former it should not be about supplements either.
It's Sunday and finally time for the wrap up of the "Maintain & Increase Your Insulin Sensitivity" Series (read all previous installments). It took me quite some time to get through all the compounds on my and your list and the outcome is far from being a "complete" list of all the agents that can have beneficial effects on your insulin sensitivity. Still, if there is at least one agent, one fact or one take home message for each of the 6 previous articles of which you would say: "Ok, I guess that was worth wasting some of my valuable time on", I would be happy.

For myself it was by the way yet another occasion to learn more  about many of the agents, I reviewed in this series.

And if you listened to the SuppVersity Science Round-Up on Thursday, you will probably remember that I said that I was at least a cautiously excited about the potential of berberine... but I am wasting your time here. Let's start with the wrap up.
Lifestyle changes are more powerful than supplements: So don't forget that it's imperative to realize the lifestyle changes described in the first installment of this series. Otherwise the best you can hope to achieve with supplements (and drugs) is to slow the progression from insulin resistance to full-blown diabetes.
Before we take a look at the three stacks I have compiled, I do just briefly want to get you up to speed as far as the major underlying mechanisms of the supplements are concerned:
  • AMPK: Some people in the medical establishment think of it as the good counter-part to mTOR. The fairy that will put an end to the pro-carcinogenic reign of the evil mTOR-witch, so to say. Others, who are mostly part of the "muscle head" community, think of AMPK as their fiercest enemy and mTOR as their brother in crime... It goes without saying that neither of these views is accurate. AMPK and mTOR are not even necessarily antagonistic - at least not for people like you - people who work out regularly. The mTOR expression after a workout does after all occur in the presence of increased an expression of AMPK. What else could you possibly ask for, if you want to "recomp" (i.e. lose fat and gain muscle to improve your physical appearance)?

    Few people know that there are two different iso-forms of AMPK. The alpha-2 isoform is the one that's expressed during a workout and it works hand in hand with mTOR and not against it (learn more)
    What may at first look like a paradox is actually easily explained if we don't look at the characteristic downstream effects of mTOR and AMPK, but rather at the circumstances in which they are activated. Outside of the previously mentioned exercise context those are in fact antagonist. With mTOR being triggered by the abundance of nutrients - specifically protein, and even more specifically leucine - you would not expect to see increases of AMPK at the same time. The latter is after all, expressed, when a cell senses a lack of nutrients in form of an increase in ADP (~used ATP) and a decrease in ATP levels. The reaction, i.e. an increased expression of AMPK will then have downstream effects on the uptake of glucose and the oxidation of fatty acids, both of which contribute to a restoration of normal ATP levels in the cell.

    Both AMPK and mTOR act highly localized. The exercise induced glucose uptake is thus muscle-specific - that should be obvious, since exercise will raise the ADP levels only in the muscle. Supplemental agents that mimic this effect, on the other hand, act systemically. Agents like alpha lipoic acid will therefore increase glucose uptake in both muscle and adipose tissue (Moini. 2002). After a workout and at other time points, where the glucose uptake is already high and, more importantly, muscle specific, it is thus not necessarily the best idea to try to "escalate" the effects by using a class of supplements that is often mislabeled as "insulin mimetics". 
  • A note on the PPAR-effects of CLA, fish oil, TTA & co: I guess as a well-read SuppVersity reader you will know that CLA is a supplemental non-starter. In human studies the outstanding results from rodent trials have never been successfully replicated. This could be - at least in parts - a result of the dosage and the ratio of t10c12 CLA to it's c9t11 counterpart, which has the exact opposite effects on the PPAR-gamma receptor (Toomey. 2005).
    Some of you will probably also remember my articles about the pertinent effects of TTA and fish oil in the. Of those only the latter has a significant PPAR-gamma activity. TTA, on the other hand is predominantly a PPAR-delta and -alpha agonist and thus more a "true fat burner" than a general "fat handler", which is probably the best way to describe fish oil (learn more).
    PPAR-gamma: If you listened to the Science Round-Up last Thursday you will have heard me say that blocking PPAR-gamma will inhibit the storage of energy in the adipose tissue. That's true, but by no means as beneficial as you may be thinking. It is, for example, pretty likely that the CLA induced PPAR-gamma blockade is also responsible for the increased propensity to develop non-alcoholic fatty liver disease in CLA fed rodents.

    The results Fedor et al. present in a 2012 paper, show that these effects can be ameliorated if the PPAR-gamma suppressor (i.e. trans-10, cis-12-conjugated linoleic acid) is combined with a supplement that exerts the opposite effects in the liver - a supplement you all know pretty well: DHA, as in "fish oil". It is, just like many of the "older" diabetes drugs, an (allegedly less) potent PPAR-G agonist (=activator; cf. Neschen. 2006).

    Whether the blockade of PPAR-gamma is a good or a bad thing does thus obviously depend on the scenario we are talking about. For the lean individual, who is working out regularly and wants to defend his leanness in the absence of (un-)wanted eating orgies and "mass building regimen" it is probably a good thing. He or she will not have an energetic surplus that could end up clogging up the liver. And while the same goes for the average obese individual who has finally gotten his act together, PPAR-gamma inhibitors would seem clearly counter-indicated for sedentary individuals on the high calorie, high sugar, high fat diet so many people consider "normal", these days.

    As paradox as it may seem, the anti-diabetic effects of PPAR-gamma activating thiazolidinediones (TZDs) which are still used to "treat" (I should rather write "manage") diabetes mellitus and other diseases that feature insulin resistance will thus come at the expense of increased body fat storage. The latter can be pretty pronounced,as the data from pre-diabetic individuals Bray et al. published only recently goes to show you (figure 1).
    Despite their anti-inflammatory effects and their (limited) use in highly inflamed type II diabetics you will therefore not find any of the herbal PPAR-gamma agonists like pomegranate, pumpkin, mellisa officinalis, morus alba, artemisia capillaris, bitter melon, guggul, banaba or mulberry (cf. Huang. 2009) in the stacks below. And that despite the fact that they have anti-inflammatory activities.
Ok, I guess you are either fed up of theoretical details by now, or were so before and just scrolled down to the "stacks" in the first place.
There is a reason there is no "athlete's stack" here: Since I know you will be asking, I thought I will say it right away. The reason that there is no "athlete's stack" in the list is that athletes are either "normal-weight insulin resistant" or they are insulin sensitive and don't need any supplements on top of the lifestyle changes from episode I. You got your workouts, folks: There is no better muscle specific insulin sensitizer out there! If you are looking for agents to stay lean try berberine, it's anti-ppar-gamma effects may help and if you want more, stack it with taurine, of which you should by now know that its benefits go well beyond "glucose sensitizing" / You don't? Well, then take a look at the previous articles about taurine.
I guess I will not make you wait any longer, then... I have come up with three scenarios, the "insulin resistant obese / overweight individual", "the normal-weight insulin resistant individual" and the "cheater" (explanations follow below the stacks):
  • Table 1: List of the most important supplements discussed in the series; more details on each of them, as well as on those I did not include in this overview can be found in the individual installments.
    The insulin resistant obese / overweight individual will have to target weight and fat loss and increases in insulin resistance; a stack that could facilitate all three would contain.
    • Metformin - 3x 300-500mg (not lipoic acid, this is why)
    • Berberine - 3x 200-400mg
    • Fucoxanthin - 3x 5mg
    • Taurine - 3x 2-3g
    • Chromium - 1x 200mcg (*)
  • The normal-weight insulin resistant individual will have to take care of inflammation, (usually) a beginning fatty liver and not taking the next step to the obese diabetic.
    • Berberine - 3x 200-400mg 
    • Chlorogenic acid - 3x 200-300mg
    • Taurine - 3x 2-3g
    • Milk thistle - 3x 200-400mg
  • The cheater can be either of the former or a healthy perfectly insulin sensitive individual who wants to reduce the sudden rise in blood glucose after a meal.
    • Cinnamon - 1-6g (Ceylon cinnamon)
    • Vinegar - 2x tablespoons
    • Green tea - 1-2 cups
The insulin resistant obese / overweight individual needs relieve most urgently, therefore he will also trial fucoxanthin, which has some impressive, but not exactly reliable weight loss data. He will either have a script for metformin or will use alpha lipoic acid (ALA) as a substitute and he will make sure that he gets adequate chromium by taking 200mcg of chromium picoliante or niacin-bound chromium per day *if this is not already in a multi he or she is taking.

The normal-weight insulin resistant individual has slightly different needs than his overweight comrade. He or she is almost certainly suffering from chronic inflammation and beginning or existing NAFLD (the obese will have that, as well, but for him it's only part of the problem). With it's effects on both AMPK and PPAR-gamma berberine will make sure that the body fat levels remain low. Just like taurine (read more), chlorogenic acid (Panchal. 2012) and milk thistle (read more), it will also help "revive" the liver and sooth the inflammation by promoting the bodies own antioxidant defense system.

The cheater, on the other hand, could be everyone who wants to undo (or fore-do, if you will) a high GI carb meal. The ingredients of this stack will ameliorate the blood sugar response and could thus potentially reduce any damage you could do to your pancreas... but let's be honest. With the occasional cheat you are not going to do any damage and if cheating becomes common practice you violate the "lifestyle-changes first!" principle and won't get away healthily no matter how much supplements you take.
Browse previous articles:

Lifestyle Changes

ALA, GABA, Taurine & Co.

Berberine, Banaba & Co.

Cinnamon, Curcumin & Co.

Lemon, Starch, Coffee & Co.

Chlorogenic acid, fucoxanthin & Co.
References:
  • Fedor DM, Adkins Y, Mackey BE, Kelley DS. Docosahexaenoic acid prevents trans-10, cis-12-conjugated linoleic acid-induced nonalcoholic fatty liver disease in mice by altering expression of hepatic genes regulating fatty acid synthesis and oxidation. Metab Syndr Relat Disord. 2012 Jun;10(3):175-80.
  • Huang TH, Teoh AW, Lin BL, Lin DS, Roufogalis B. The role of herbal PPAR modulators in the treatment of cardiometabolic syndrome. Pharmacol Res. 2009 Sep;60(3):195-206.
  • Moini H, Tirosh O, Park YC, Cho KJ, Packer L. R-alpha-lipoic acid action on cell redox status, the insulin receptor, and glucose uptake in 3T3-L1 adipocytes. Arch Biochem Biophys. 2002 Jan 15;397(2):384-91.
  • Neschen S, Morino K, Rossbacher JC, Pongratz RL, Cline GW, Sono S, Gillum M, Shulman GI. Fish oil regulates adiponectin secretion by a peroxisome proliferator-activated receptor-gamma-dependent mechanism in mice. Diabetes. 2006 Apr;55(4):924-8. 
  • Panchal SK, Poudyal H, Waanders J, Brown L. Coffee extract attenuates changes in cardiovascular and hepatic structure and function without decreasing obesity in high-carbohydrate, high-fat diet-fed male rats. J Nutr. 2012 Apr;142(4):690-7.
  • Toomey S, Harhen B, Roche HM, Fitzgerald D, Belton O. Profound resolution of early atherosclerosis with conjugated linoleic acid. Atherosclerosis. 2006 Jul;187(1):40-9. Epub 2005 Sep 22.

Monday, August 26, 2013

The Quest For the Best N6:N3 Ratio. Swine Study Suggests: 5:1 is Healthy, 1:1 Will Also Cut Fat and Build Muscle

 Yes, this study is about omega-3s, but it is not about the beneficial effects of fish oil.
Ok, I see you are totally excited, so I am not going to beat around the bush for long: According to a soon-to-be-published study from the Hunan Provincial Engineering Research Center of Healthy Livestock, Institute of Subtropical Agriculture at the Chinese Academy of Sciences  a 5:1 ratio of n-6:n3 (as in omega-6 to omega-3) is good enough to keep pigs healthy.

Kicking out another couple of grams of omega-6 fatty acids, on the other hand, had pretty intriguing effects on the body composition of the ninety-six male cross-bred (Large White£
Landrace) pigs who happened to weigh about as much as an average human being (another advangate, of swine - HED calculations are not necessary; learn more).
Did you know that pigs are opportunistic omnivores just like us and provide a better model of human metabolism than our little, furry remote cousins with the big round eyes and the long tails who are populating the laboratory cages of scientists all around the world (cf. Miller. 1987)?
Lineseed or soybean - that makes all the difference

I hope you did not already start popping fish oil, while you are reading this. After all, in this case the glorified residual waste from the fishery industry did not contribute to either the health or weight loss benefits Duan et al. observed in their pigs who were fed one of the four isoenergetic diets with n6:n-3 PUFA ratios of 1:1, 2·5:1, 5:1 and 10:1 for 2 months.

Table 1: Ingredients, nutrient and fatty acids composition of the diets the pigs received; † vitamin premix (Duan. 2013)
As the ingredient profiles of the different diets (table 1) tell you the major source of omega-3 fatty acids was lineseed oil. The latter is basically devoid of long-chain omega-3 fatty acids (EPA & DHA). Instead, it contains the short-chain variety aka alpha-linolenic acid that is often laughed at in the health and fitness community as being the useless precursor to the powerful "fish oils" EPA and DHA (note: the level of DHA was identical in all diets!).

So, no fish oil, just ALA

Although the allegedly more potent LC-PUFAs were missing, the changes in body composition and the overall improvement (=reduction) of the activity of the potentially pro-carcinogenic PI3K-alpha gene and the fat storage genes FATP-1 and PPAR-gamma (learn more about PPAR-gamma) were still impressive.

If you take a closer look at the data in figure 1, though, you will realize that the effects on body composition require a reduction to 2.5:1, better 1:1 to become significant.
Figure 1: Feed conversion rate, muscle mass, adipose tissue mass, lean to fat mass ratio expressed relative to the levels of the pigs in the 5:1 n6:n3 group after 2 months on the different diets (Duan. 2013)
At the same time there is a clear relationship between increased adiposity and the amount of soybean oil in the pig diets. Thank god that the USDA in their incredible wisdom lists it among the top dietary sources for fat *sarcasm*.

Ah, I'd better not get political here, but let me point out one thing: In view of the currently available scientific evidence it borders physical injury resulting from negligence that the "guidelines" do not put an emphasis on the reduction of the the crazily high n-6:n-3 ratio of the Standard American Diet (16-17:1).

Unlike this pig study, a previous rodent study suggests you should pick EPA over DHA over ALA for weight loss purposes (learn more)
Bottom line: This is one of the most convincing well-controlled animal studies we have that would support that the purportedly "paleolesque" 1:1 ratio of n-6:n-3 fatty acids entails highly significant health benefits,  even if those omega-3 fatty acids don't come from fish, but from lineseed oil.

One thing we must not forget, though, is the fact that the beneficial changes in health and body composition were brought about by the concomittant reduction in omega-6 and increase in omega-3 fatty acids. Simply drinking a bottle of lineseed or cod liver oil everyday could thus do more harm than good, because with ~3g of oil per 100g the diet was also low in total fat and almost devoid of saturated fats and whether the same results would occur in a high fat scenario is beyond what the study at hand can tell us.

References:
  • Duan Y, Li F, Li L, Fan J, Sun X, Yin Y. n-6:n-3 PUFA ratio is involved in regulating lipid metabolism and inflammation in pigs. Br J Nutr. 2013 Aug 15:1-7. [Epub ahead of print]
  • Miller ER, Ullrey DE. The pig as a model for human nutrition. Annu Rev Nutr. 1987;7:361-82. Review.

Sunday, April 14, 2013

Fighting to Stay Lean? These 20+ Anti-Obesity Agents Have the Potential to Inhibit Fat Gain Right at the Cellular Level

No, none of the 20 agents in the list below is going to do the work for you, but they could help you "conserve" the results, keep you lean on a bulk and/or avoid the hazardous Yoyo effect when you go off a die.
It's actually normal that the introduction is the last part of an article I write. What's special about today's SuppVersity article is thus not that I write the introduction at the end, but that I did not really know what I would be writing here, when I set out to compile the unsorted (but not chaotic) list of potential anti-obesity agents below. All of them act by pathway(s) you as a SuppVersity reader will have read about before, most prominently AMPK, and the peroxisome proliferator receptors (PPARs), of which the blockade of the obesogenic PPAR-gamma pathway, which is the main working principle of CLA turned out to be the go-to explanation for the ability of these agents to block both the differentiation of adipocytes and the storage of triglycerides in existing fat cells.

20 more or less proven anti-obesity agents for the weekend

As you are about to see, the list, which was never intended to be complete, got pretty and I guess I could add a couple of additional items, if I spent more time digging. In order not to steal your and waste more of my precious time on this sunny (finally!) Sunday, I did yet decide to call it a day, when I hit the 20-items mark. Now it's up to you to invest some of your sunny Sunday time, to read up on the details. 
  • On a side note: The "holy" vitamin D does the exact opposite, if you incubate preadipocytes with 25(OH)D(3) this will lead to a significant increase in the active 1,25(OH)(2)D(3) and enhanced adipogenesis in primary mouse. Reason enough for a group of Thai researchers to conclcude that "vitamin D status may [actually] regulate human adipose tissue growth and remodeling." (Nimitphong . 2012)
    Vitamin A - Retinoic acid upregulates the expression of the adipogenesis inhibitors Pref-1, Sox9, and Kruppel-like factor 2 (KLF2) to "suppress adipogenesis in vivo and that the activity significantly contributes to the ability of the hormone to counteract diet-induced obesity." (Berry. 2012) Previous studies have also shown that all-trans-retionic acid directly increases the activity of PPARbeta/delta and so that Berry & Noy conclude "RA may be a uniquely efficacious agent in the therapy and prevention of the metabolic syndrome." (Berry. 2009) Similar results have been reported and conclusions have been drawn by Brun et al. and Sagara et al. (Brun. 2012; Sagara. 2013). Finally, Hisada et al report that - just like testosterone (learn more) - retinoic acid ensures that mesenchymal stem cells (MSCs) become osteoblasts (bone precursor cells), not fat cells (Hisada. 2013).
  • Bromocriptine - If you do know it at all, then probably for it's ability to decrease the "milk hormone" prolaction. If you take a look at the broad spectrum of physiological effects of prolactin, the effect it has on the mammalian mammary gland is really negligible. A recent study from the Department of Biotechnology at the Daegu University in The Republic of Korea does now suggest that the inhibition of adipogenesis (formation of new fat cells) and lipogenesis (storage of lipids in existing fat cells) via decreased expressions of the adipogenic activators Pparα, Pparγ, and Cebpα, as well as major lipogenic target genes, including Me1, Acc1, 6Pgd, Fasn, and Prkaa1 is one of these "auxiliary functions" (Mukherjee. 2013)
  • EC also boosts erectile performance and testosterone (learn more)
    Ecklonia cava (EC) - or rather the dioxinodehydroeckol (DHE) molecules that are contained in this type of brown seaweed "exert[s] its anti-adipogenic effect on adipocyte differentiation through the activation and modulation of the AMPK signaling pathway" (Kim. 2010a). As a SuppVersity reader, you will be aware that this effect has been confirmed in in-vivo studies, later on (learn more).

    What's probably Interestingly DHE is not the only anti-adipogenic agent in brown sea algae, Fucoidan, a sulfated polysaccharide from brown seaweeds has likewise been reported to affect the development of adipocytes. In 2010, Kim et al. were able to show that it targets the MAPK kinase pathway by inhibiting the the expression of both early CCAAT-enhancer-binding proteins alpha (C/EBPalpha) and peroxisome proliferator-activated receptors gamma (PPARgamma), as well as the late activating protein 2 (aP2) adipogenic transcription factors (Kim. 2010b).
  • Curcumin - While you my get the impression there was nothing curcumin cannot do (learn more), I am not whether the anti-PPAR gamma effects of curcumin are a result of it's anti-inflammatory effects or not... be that as it may, Lee et al. have demonstrated in 2009 already that the stimulatory effect curcumin exerts on the AMPK expression of adipocytes results in a down-regulation of PPAR-gamma in 3T3-L1 adipocytes (Lee. 2009).
  • Resveratrol - Similar popularity, similar "cures it all" status and similar effects on AMPK and downstream PPAR-gamma expression in 3T3-L1 adipocytes... actually I would not need another bulletin point for resveratrol which acts by the exact same pathway(s) s curcumin to inhibit fat cell differentiation (Chen. 2011)
  • Creatine RT by Athletic Edge Nutrition; contains a cousin of ASL and is supposed to be another "super creatine" -  True or False? The 2011 SuppVersity article has the answer (read it!).
    Artemisia sacrorum Ledeb. (ASL) - Extracts from the small shrub have been used in Oriental Medicine for centuries, in 2011 Yuan et al. were able to show that ASL "down-regulate[s] the adipogenesis-related gene expression of the sterol regulatory element-binding protein 1c (SREBP1c) and its target genes, such as fatty acid synthase (FAS), stearoyl-CoA desaturase 1 (SCD1) and glycerol-3-phosphate acyltransferase (GPAT) in a concentration-dependent manner" (Yuan. 2011) The effects are meediated by a reduced expression of the peroxisome proliferator-activated receptor γ (PPARγ) and of the CCAAT/enhancer binding protein-α (C/EBPα), both of which are key transcription factors in adipogenesis.

    With the concomitant reduction in adipocyte fatty acid binding protein (aP2) gene expression, ASL is another potential anti-obesity agent of which Yuan et al. propose that it works its  anti-adipogenic magic via AMPK activation. In view of the fact that the same is true for the fat accumulation in human liver cells, it could serve a viable tool "in the prevention of serious diseases such as fatty liver and type-2 diabetic mellitus" (Yuan. 2010). Related increases in fatty acid oxidation have been observed in a rodent study by Hong later in 2009 with another variety of Aertemisia, namely Artemesia Capillaris (Hong. 2010). The human equivalent dosage in this trial wast 8mg/kg of the ethyl acetate fraction of the shrub.
  • Phosphorylated glucosamine - While you will probably remember that large doses of regular glucosamine have been associated with insulin resistance (see previous installment of "True Or False"), it's phosphorylated variety glucosamine-6-phosphat (PGlc), Kong et al. synthesized using methanesulfonic acid, phosphorus pentoxide (P(2)O(5)), NH(2)NH(2) and DMF "significantly reduced lipid accumulation during adipocyte differentiation and induced down-regulation of peroxisome proliferator-activated receptor-gamma, sterol regulatory element binding protein 1 and CCAAT/enhancer binding protein-alpha in a dose-dependent manner." (Kong. 2010)
    Phosphorylated glucosamine works (like most of the anti-obesity agents, including the well-known conjugated linoleic acid by reducing the expression of PPAR-gamma (left). It's dose-dependent effects are yet not restricted to the peroxisome proliferator receptor, but affect the pro-adipogenic genes C/EBP-alpha and SREBP1, as well (right; Kong. 2010)
    What's also worth mentioning is that the in-vitro study from the Marine Bioprocess Research Center at the Pukyong National University in South Korea also revealed that PGcl also hampered the maturation of pre-adipocytes by down-regulating adipocyte-specific gene promoters such as adipocyte fatty acid binding protein, fatty acid synthase, lipoprotein lipase and leptin. In conjunction "[t]hese results suggest that the inhibitory effect of PGlc on adipocyte differentiation might be mediated through the down-regulation of adipogenic transcription factors, such as peroxisome proliferator-activated receptor-gamma, sterol regulatory element binding protein 1 and CCAAT/enhancer binding protein-alpha, which are related to the downstream adipocyte-specific gene promoters" (Kong. 2010) 
  • Add. reads: "Temporary +100kcal/Day Cold Thermogenesis Response W/ Exotic Ginger Extract" (more) "250-1000mg of Freeze-Dried Ginger Reduce Visceral Fat Even When Rodents Are Fed an Obesogenic High Fat Diet" (more).
    6-gingerol (6G) - The active ingredient in ginger has just been shown to block the obesity effects of the anti-diabetes med rosiglitazone (Tzeng. 2013). It does so by blocking the PPAR-gamma mediated effects of the "store the superfluous energy as body fat"-drug and was thus able to suppress the oil droplet accumulation and reduce the sizes of the droplets in the course rosiglitazone(RSG)-induced adipocyte differentiation in 3T3-L1 cells. Since it also blunted the increased levels of mRNA and protein in adipocyte-specific fatty acid binding protein 4 and fatty acid synthase induced by RGZ, it can be expected that 6G will not only inhibit the accrual of new, but also the (re-)filling of existing fat cells. 
  • Piperine and capsaicin - In view of the fact that piperine is a "quasi-cousins" of 6-gingerol, it is actually not really surprising that it shares similar effects on the expression of PPAR-gamma (Park. 2012). It is therefore not surprising that the third member of this spicy triumvirate, i.e. capsaicin, shares the exact same PPAR-gamma reducing effects (Joo. 2010).
  • Berberin - Contrary to many other items on the list, berberin's anti-PPAR-gamma effects are actually pretty well-known. There is ample evidence from in-vitro (Huang. 2006; Liu. 2009) and in-vivo (Lee. 2006) evidence that it blunts fat gain by increasing the catabolism of high energy intermediates, upregulating AMPK, modulating the expression of the GATA-2 and 3 gene and reducing the expression of (you guessed it) PPAR-gamma (Hu. 2009).
    Table 1: Berberine content of various commercially available supplements (Brown 2008)
    Berberine has also been shown to improve endothelial function in man (Wang. 2009) and promote the "longevity and mitochondrial health gene" SIRT1 in obesity ridden, insulin resistant skeletal muscle (Gomes. 2012).
  • Ginsenosides (spec. ginsenoside Rg3) - Just like ginereol (see above) ginsenoside Rg3 has been shown to block the adipogenic effects of the anditiabetic drug rosiglitazone via an AMPK/PPAR-gamma dependent pathway (Hwang. 2009). It may be worth mentioning that at least the effect triglyceride storage was not dose-dependent. Once  a threshold amount of 40µM was reached, the adipocytes that were incubated with Rg3 did not "lose" any additional triglycerides, when the dosage was increased to 80µM.
  • On a side note: Although promoted in the same health and longevity circles as CAPE, the hailed "telomerase lengthener" Astraglaus is a PPAR-gamma promoter and will thus "enhance the accumulation of lipid drops, and increase the terminal differentiation of preadipocytes" (Liu. 2007)
    Caffeic acid phenethyl ester (CAPE) - You've heard about the anti-inflammatory, muscle protective ability of this compound from bee propolis only recently (go back). In addition to being a potent anti-inflammatory, the natural phenolic compound that's also found in a variety of plants, has also been found to block the conversion of mouse fibroblasts into fat cells (Juman. 2010). As for most of the other agents the effects of CAPE appear to be mediated by a reduction inperoxisome proliferator-activated receptor (PPAR) gamma and CCAAT/enhancer-binding protein (C/EBPalpha) and concomittant reduction isn fatty acid synthetase and the expression of adipocyte-specific fatty acid binding protein (aP2). 
  • Lysimachia foenum-graecum (LFE) - LFE is a Chinese herb and well-known anti-inflammatory from Oriental Medicine. The anti-obesity effect of L. foenum-graecum extract was first discovered by Seo et al., when they simply screened a whole host of potential natural agents for their anti-adipogenic effects. In 2011 the researchers found that "LFE blocked the differentiation of 3T3-L1 preadipocyte in a dose-dependent manner with an IC50 of 2.5 μg/ml". The underlying mechanism which has also been observed in an in-vivo rodent study with 100 mg/kg/day, are - how else could it be - mediated by the inhibition of PPARγ and C/EBPα expression.
    Effects of the administration of an lysimachia foenum-graecum ethanol extract on lipid and glucose metabolism and adipokine signalling in mice on an obesogenic diet (Seo. 2011)
    Moreover, LFE stimulated fatty acid oxidation in an AMPK-dependent manner, greatly improved serum levels of obesity-related biomarkers such as glucose, triglycerides, and adipocytokines leptin, adiponectin, and resistin and lead to an effective decrease in total body weight gain in mice who received 30, 100, and 300 mg/kg/day of an Lysimachia foenum-graecum ethanol extract (50:6; LFE) in addition to their obesogenic high fat diet (see figure above). The mice in the HFD + LFE group did simply have lower body weights, they also had a reduced amount of adipose tissues especially within the metabolically active and highly unhealthy abdominal subcutaneous, epididymal, and perirenal adipose tissue.
  • Photos of the lean (A and D), HFD-fed (B and E) and HFD-fed + SRLE supplemented (C and F) mice in the Thounaojam study (2011).
    Sida rhomboidea. Roxb leaf extract (SRLE) - SRLE does only sound like the stuff many supplement companies used after the ban of mua huang (natural source of ephedrine). It is however a different variety of Sida (Batyάlaka, Sida cordifolia)... well, at least it is from the same family which lacks the CNS stimulating activity of mua huang. With its ability to prevent high fat diet (HFD) induced visceral adiposity by down-regulation of PPARγ2 and leptin gene expression it could in fact work synergistically with ephedrine, though. After all the HED of the 24% w/w water extract Thounaojam et al. used to prevent the obesogenic effects of a hypercaloric high fat diet in their rodent study amounts to no more than ~40mg/kg and since SRLE has been shown to be non-toxic up to 3g/kg (in mice; HED ~240mg/kg) it would be interesting to see studies that probe whether it works in humans (Thounaojam. 2011).
  • SH21B is an anti-obesity composition composed of seven herbs: Scutellaria baicalensis Georgi, Prunus armeniaca Maxim, Ephedra sinica Stapf, Acorus gramineus Soland, Typha orientalis Presl, Polygala tenuifolia Willd and Nelumbo nucifera Gaertner (active ingredients; see figure below) that has been used for the treatment of obesity in traditional medical clinics in Korea and has recently been shown to decrease the expression of major transcription factors of the adipogenesis pathway and result in the down-regulation of lipid metabolizing enzymes involved in the transport, uptake and synthesis of lipids - unfortunatedly, only in vitro (Lee. 2009)
    Effects of SH21B on fat droplet formation in 3T3-L1 cells (top) and size of adipocytes in adipose tissue. (bottom), as well as active ingredients in SH21B (based on Lee. 2009)
    As you can see in the stains from the adipose tissue of the above, the effects are clearly mediated by both an inhibition of the maturation of preadipocytes (top) and the inhibition of fat storage... now you tell me the world needs "new" anti-obesity agents!? I mean, it's quite obvious that the Koreans knew all along what keeps you lean ;-)
  • Lactobacillus plantarum KY1032 cell extract - Before you begin to jubilee about the triumph march of probiotics, let me tell you this: I am not sure how on earth the remnants of a gut bacterium are supposed to reach your adipocyte tissue in a healthy individual without a leaky gut. Against that background I am not sure, whether it is even necessary to mention that Park et al. observed in 2011 that a cell exctract of the KY1032 strain of lactobacilli is another compound that can down-regulate the expression of peroxisome proliferator-activated receptor-γ2, CCAAT/enhancer binding protein-α, fatty acid synthase, and adipocyte-fatty acid binding protein and thus blunt fat gains in vitro... ah, now I wrote it down, so I'll just leave it here ;-) 
  • Irvingia gabonensis seed extract - Likewise not a newcomer to the supplement the African / Southeast Asian tree, respectively an extract from its seeds has been shown to dose-dependently decrease the expression of PPAR-gamma in murine adipose cells in the petri dish in a 2008 study by scientists from  Faculty of Science, University of Yaoundé in Cameroon and the Wake Forest University School of Medicine in Winston-Salem, USA (Oben. 2008).
The in-vitro study shows, CAF may inhibit fat storage, but it does not "squeeze" the fat out of the cells (data based on Kim. 2012)
  • Citrus aurantium falvenoids (CAF)- Despite the fact that most of you will probably have realized in N=1 experiments that citrus aurantium is a supplemental non-starter as a fatburner. It has (in-vitro) the ability to reduce the epxression of C/EBPβ and subsequently inhibit the activation of PPARγ and C/EBPα. So unless you have taken tons of pure CAF supplements during your last bulk, it is no wonder that you did not realize any effect from the fat burner you bought last summer. After all you are not storing any fat when you are dieting anyway... and I guess you have been dieting, when you took that product, right?

    Apropos dieting, the data in the figure on the right also shows that citrus aurantium, alone, won't help with that. After all it lacks the ability to increase LPL and thus the release of free fatty acids from the triglyceride stores in your fat stores.
  • Silibinin (from milk thistle) - You will probably have heard that milk thistle can help replenish the antioxidative defenses of your liver and thus prevent all sorts of systemic toxicities (learn more). At least in-vitro silibinin (aka silybin), the major active ingredient in silymarin, can also prevent the accumulation of triglycerides in existing, as well as the formation / maturation of future adipocytes. From a mechanistic point of view, the effect is mediated by the usual suspects respectively their downregulation (CAAT/enhancer binding protein-alpha, fatty acid synthase, sterol response element binding protein 1c, adipocyte-specific lipid binding protein, peroxisome proliferator-activated receptor gamma and lipoprotein lipase; cf. Ka. 2009).
  • Stem bromelain (SBM) - Just as so many of the previously mentioned agents, SBM, a specific member of the bromelain family you may know as "pineapple enzyme", is by no means a "new kid on the anti-fatloss block". Rather than that it has been used for centuries in traditional medicine as - guess what? - an anti-obesity agent. Now, I would never suggest that all TCM medicines work, but for stem bromelain it does at least seem as if the in-vitro studies, Dave et al. conducted about a year ago would support the notion that the ingestion of respective supplements can in fact exert beneficial effects on the accumulation of body fat (Dave. 2012).
    Illustration of the mechanism and selected downstream effects of stem bromelain (SBM) on fat cells in the petri dish (compiled based on data from Dave. 2012)
    At the molecular level, SBM targets the same adipogenesic genes as (almost all) of the previous agents. What's interesting though, is the fact that the scsientists also found that "SBM's ability to repress PPARγ expression seems to stem from its ability to inhibit Akt and augment the TNFα pathway." (Dave. 2012) In other words, it's the increase in "bad" TNF-alpha and the decrease in the purportedly muscle, but in fact simply "mass building" Akt-TSC2-mTORC1 pathway that entails the apoptosis (controlled cell death) of mature adipocytes and lipolysis.
With the stem bromelain this comprehensive, but by no means all-encompassing list of "proven" (mostly only in vitro) anti-adipogenic agents, has come full circle. After all, Dave et al. point out that their data would indicate that stem bromelain, together with all-trans retinoic-acid (atRA), which is a metabolite of vitamin A, the first item on our list "may be a potent modulator of obesity by repressing the PPARγ-regulated adipogenesis pathway at all stages and by augmenting TNFα-induced lipolysis and apoptosis in mature adipocytes." (Dave. 2010).

It's not just beyond the scope of this article, but - in the majority of the cases simply not known - whether or not the TNFα increase is an integral part of the anti-obesity effects of all of the aforementioned compounds. As far as the inhibition of PPAR-gamma is concerned things are different, though. With PPAR-gamma being the central "fat storage" switch, its deactivation and the entailing blockade of adipocyte differentiation, pre-adipocyte maturation and triglyceride storage is currently probably the most effective anti-obesity  mechanism we know. A mechanism that is way more fundamental than the diet-induced and stimulant / alpha/beta-agaonist (caffeine, ephedra, clenbuterol, yohimine) supported emptying of existing adipocyte triglyceride stores.



I know it's not popular, but in the case of vitamin D we already have evidence of it's obesity promoting effects (read more). It's straight forward experimental evidence, much contrary to the epidemiological guesswork on the basis of which people are popping vitamin D pills, these days.
Keep in mind: Most of the data is derived from in-vitro studies. Few compounds do have actual evidence from rodent studies and the number of substances that showed beneficial effects in human studies is even smaller.

Nevertheless, the above list harbors a number of compounds which could be of great interest for the lean physical culturist, for whom (at least physique-wise) stuff like vitamin D (note: the effects could be dose-dependent with benefits at low, and detrimental effects at high levels), astragalus and the rest of the healthy, but pro-adipogenic agents that can help obese individuals to stash away the tons of sugar and fat floating through their arteries are of little use.

Against that background I want to close this post with a warning, or I should say a reminder of the the fact that the effects of PPAR-gamma are physiologically important (e.g. prevention of lipotoxicity, Medina-Gomez. 2007) and go beyond "just making you fat" in how it would be worth striving to suppress it altogether is thus questionable (suggested read: CLA Destroys Body Fat). Since for all of the previously discussed agents that have in-vivo data to support their efficacy have postivite, not negative "side effects" (think of curcumin, gingerol, ginseng, etc.), it is yet unlikely that the use of reasonable amounts of one or a stack of many of them is going to harm you.

Just keep in mind: The goal should be to keep the PPAR-gamma activity in check, not to annihilate it. Consequently you should not and cannot expect to be able to "eat whatever you want and still stay lean" by supplementing with any of the agents above. On the other hand, they can hardly be even less useful than the vast majority of currently available arsenal of OTC "fat burners" ;-)

References:
  • Berry DC, Noy N. All-trans-retinoic acid represses obesity and insulin resistance by activating both peroxisome proliferation-activated receptor beta/delta and retinoic acid receptor. Mol Cell Biol. 2009 Jun;29(12):3286-96.
  • Berry DC, DeSantis D, Soltanian H, Croniger CM, Noy N. Retinoic acid upregulates preadipocyte genes to block adipogenesis and suppress diet-induced obesity. Diabetes. 2012 May;61(5):1112-21. 
  • Brown PN, Roman MC. Determination of hydrastine and berberine in goldenseal raw materials, extracts, and dietary supplements by high-performance liquid chromatography with UV: collaborative study. J AOAC Int. 2008 Jul-Aug;91(4):694-701.
  • Brun PJ, Yang KJ, Lee SA, Yuen JJ, Blaner WS. Retinoids: Potent regulators of metabolism. Biofactors. 2012 Dec 22. doi: 10.1002/biof.1056. 
  • Chen S, Li Z, Li W, Shan Z, Zhu W. Resveratrol inhibits cell differentiation in 3T3-L1 adipocytes via activation of AMPK. Can J Physiol Pharmacol. 2011 Nov;89(11):793-9.
  • Gomes AP, Duarte FV, Nunes P, Hubbard BP, Teodoro JS, Varela AT, Jones JG, Sinclair DA, Palmeira CM, Rolo AP. Berberine protects against high fat diet-induced dysfunction in muscle mitochondria by inducing SIRT1-dependent mitochondrial biogenesis. Biochim Biophys Acta. 2012 Feb;1822(2):185-95.
  • Hisada K, Hata K, Ichida F, Matsubara T, Orimo H, Nakano T, Yatani H, Nishimura R, Yoneda T. Retinoic acid regulates commitment of undifferentiated mesenchymal stem cells into osteoblasts and adipocytes. J Bone Miner Metab. 2013 Jan;31(1):53-63.
  • Hong JH, Hwang EY, Kim HJ, Jeong YJ, Lee IS. Artemisia capillaris inhibits lipid accumulation in 3T3-L1 adipocytes and obesity in C57BL/6J mice fed a high fat diet. J Med Food. 2009 Aug;12(4):736-45.
  • Hu Y, Davies GE. Berberine increases expression of GATA-2 and GATA-3 during inhibition of adipocyte differentiation. Phytomedicine. 2009 Sep;16(9):864-73. doi: 10.1016/j.phymed.2009.03.002. Epub 2009 Apr 28.
  • Huang C, Zhang Y, Gong Z, Sheng X, Li Z, Zhang W, Qin Y. Berberine inhibits 3T3-L1 adipocyte differentiation through the PPARgamma pathway. Biochem Biophys Res Commun. 2006;348:571–578.
  • Hwang JT, Lee MS, Kim HJ, Sung MJ, Kim HY, Kim MS, Kwon DY. Antiobesity effect of ginsenoside Rg3 involves the AMPK and PPAR-gamma signal pathways. Phytother Res. 2009 Feb;23(2):262-6.
  • Joo JI, Kim DH, Choi JW, Yun JW. Proteomic analysis for antiobesity potential of capsaicin on white adipose tissue in rats fed with a high fat diet. J Proteome Res. 2010 Jun 4;9(6):2977-87.
  • Juman S, Yasui N, Okuda H, Ueda A, Negishi H, Miki T, Ikeda K. Caffeic acid phenethyl ester inhibits differentiation to adipocytes in 3T3-L1 mouse fibroblasts. Biol Pharm Bull. 2010;33(9):1484-8.
  • Ka SO, Kim KA, Kwon KB, Park JW, Park BH. Silibinin attenuates adipogenesis in 3T3-L1 preadipocytes through a potential upregulation of the insig pathway. Int J Mol Med. 2009 May;23(5):633-7.
  • Kim SK, Kong CS. Anti-adipogenic effect of dioxinodehydroeckol via AMPK activation in 3T3-L1 adipocytes. Chem Biol Interact. 2010a Jun 7;186(1):24-9.
  • Kim KJ, Lee OH, Lee BY. Fucoidan, a sulfated polysaccharide, inhibits adipogenesis through the mitogen-activated protein kinase pathway in 3T3-L1 preadipocytes. Life Sci. 2010b May 22;86(21-22):791-7.
  • Kim GS, Park HJ, Woo JH, Kim MK, Koh PO, Min W, Ko YG, Kim CH, Won CK, Cho JH. Citrus aurantium flavonoids inhibit adipogenesis through the Akt signaling pathway in 3T3-L1 cells. BMC Complement Altern Med. 2012 Apr 3;12:31.
  • Kong CS, Kim JA, Eom TK, Kim SK. Phosphorylated glucosamine inhibits adipogenesis in 3T3-L1 adipocytes. J Nutr Biochem. 2010 May;21(5):438-43. 
  • Lee YS, Kim WS, Kim KH, Yoon MJ, Cho HJ, Shen Y, Ye JM, Lee CH, Oh WK, Kim CT, et al. Berberine, a natural plant product, activates AMP-activated protein kinase with beneficial metabolic effects in diabetic and insulin-resistant states. Diabetes. 2006;55:2256–2264. 
  • Lee YK, Lee WS, Hwang JT, Kwon DY, Surh YJ, Park OJ. Curcumin exerts antidifferentiation effect through AMPKalpha-PPAR-gamma in 3T3-L1 adipocytes and antiproliferatory effect through AMPKalpha-COX-2 in cancer cells. J Agric Food Chem. 2009 Jan 14;57(1):305-10.
  • Lee H, Kang R, Yoon Y. SH21B, an anti-obesity herbal composition, inhibits fat accumulation in 3T3-L1 adipocytes and high fat diet-induced obese mice through the modulation of the adipogenesis pathway. J Ethnopharmacol. 2010 Feb 17;127(3):709-17.
  • Liu Y, Wang WJ, Chen WH, Yin J. [Effects of Astragalus polysaccharides on proliferation and differentiation of 3T3-L1 preadipocytes]. Zhong Xi Yi Jie He Xue Bao. 2007 Jul;5(4):421-6.
  • Liu Y, Lou SY, He YM. [Effects of berberine on cell proliferation, peroxisome proliferation activated receptor gamma, CAAT/enhancer binding protein mRNA and protein expression in 3T3-L1 pre-adipocytes]. Zhongguo Zhong Xi Yi Jie He Za Zhi. 2008 Nov;28(11):1005-9.
  • Medina-Gomez G, Gray SL, Yetukuri L, Shimomura K, Virtue S, Campbell M, Curtis RK, Jimenez-Linan M, Blount M, Yeo GS, Lopez M, Seppänen-Laakso T, Ashcroft FM, Oresic M, Vidal-Puig A. PPAR gamma 2 prevents lipotoxicity by controlling adipose tissue expandability and peripheral lipid metabolism. PLoS Genet. 2007 Apr 27;3(4):e64.
  • Mukherjee R, Yun JW. Bromocriptine inhibits adipogenesis and lipogenesis by agonistic action on α2-adrenergic receptor in 3T3-L1 adipocyte cells. Mol Biol Rep. 2013 May;40(5):3783-92.
  • Nimitphong H, Holick MF, Fried SK, Lee MJ. 25-hydroxyvitamin D₃ and 1,25-dihydroxyvitamin D₃ promote the differentiation of human subcutaneous preadipocytes. PLoS One. 2012;7(12):e52171.
  • Oben JE, Ngondi JL, Blum K. Inhibition of Irvingia gabonensis seed extract (OB131) on adipogenesis as mediated via down regulation of the PPARgamma and leptin genes and up-regulation of the adiponectin gene. Lipids Health Dis. 2008 Nov 13;7:44.
  • Park DY, Ahn YT, Huh CS, Jeon SM, Choi MS. The inhibitory effect of Lactobacillus plantarum KY1032 cell extract on the adipogenesis of 3T3-L1 Cells. J Med Food. 2011 Jun;14(6):670-5.
  • Park UH, Jeong HS, Jo EY, Park T, Yoon SK, Kim EJ, Jeong JC, Um SJ. Piperine, a component of black pepper, inhibits adipogenesis by antagonizing PPARγ activity in 3T3-L1 cells. J Agric Food Chem. 2012 Apr 18;60(15):3853-60.
  • Sagara C, Takahashi K, Kagechika H, Takahashi N. Molecular mechanism of 9-cis-retinoic acid inhibition of adipogenesis in 3T3-L1 cells. Biochem Biophys Res Commun. 2013 Mar 29;433(1):102-7. 
  • Seo JB, Choe SS, Jeong HW, Park SW, Shin HJ, Choi SM, Park JY, Choi EW, Kim JB, Seen DS, Jeong JY, Lee TG. Anti-obesity effects of Lysimachia foenum-graecum characterized by decreased adipogenesis and regulated lipid metabolism. Exp Mol Med. 2011 Apr 30;43(4):205-15.
  • Thounaojam MC, Jadeja RN, Ramani UV, Devkar RV, Ramachandran AV. Sida rhomboidea. Roxb Leaf Extract Down-Regulates Expression of PPARγ2 and Leptin Genes in High Fat Diet Fed C57BL/6J Mice and Retards in Vitro 3T3L1 Pre-Adipocyte Differentiation. Int J Mol Sci. 2011;12(7):4661-77.
  • Tzeng TF, Chang CJ, Liu IM. 6-Gingerol Inhibits Rosiglitazone-Induced Adipogenesis in 3T3-L1 Adipocytes. Phytother Res. 2013 Mar 21.
  • Wang JM, Yang Z, Xu MG, Chen L, Wang Y, Su C, Tao J. Berberine-induced decline in circulating CD31+/CD42- microparticles is associated with improvement of endothelial function in humans. Eur J Pharmacol. 2009;614:77–83.
  • Yuan HD, Yuan HY, Chung SH, Jin GZ, Piao GC. An active part of Artemisia sacrorum Ledeb. attenuates hepatic lipid accumulation through activating AMP-activated protein kinase in human HepG2 cells. Biosci Biotechnol Biochem. 2010;74(2):322-8.
  • Yuan HD, Piao GC. An active part of Artemisia sacrorum Ledeb. inhibits adipogenesis via the AMPK signaling pathway in 3T3-L1 adipocytes. Int J Mol Med. 2011 Apr;27(4):531-6.

Monday, January 7, 2013

20 Weeks of Gluttony Without Gaining a Single Gram of Visceral Fat? A Water Extract From Hops Made It Possible

Hops: More than an ingredient of the majority of OTC sleeping pills (photo LuckyStarr)
Hops beer made from the female flowers of Humulus lupulus was the (safer) alternative to untreated water in medieval Europe. Hops are the female flowers (also called seed cones or strobiles) of a hop species and are currently still used as a flavoring and stability agent in beer. Aside from that, the vigorous, climbing, herbaceous perennial has a longstanding history of medical uses and is probably best known for its sedative effects. That a hot water extract from hop could make an excellent addition to an anti-obesity and even fat loss regimen is yet news and - in view of its efficacy - even SuppVersity news ;-)

Eat like a pig, look like a goddess with hops!

Actually the subheading is pretty unfair, after all pigs don't eat much different from us, they are opportunistic omnivores... but this is no biology lesson, so let's get back to the topic at hand. There was a time, when I thought that 99% of us would eat crap all day, if it would not make us fat - well, unless I realized that I would not and that there are many others out there who don't even like crap (=convenience food) who would refuse to eat pizza, chips, fries, pancakes, ... all day long. That being said, imagine you could do just that or, if you were a rodent in a lab cage, gorge yourself on a high fat diet with 30% maize starch, 14% casein, 10% sugar, 5% cellulose, 4% soyabean oil, 32.5% lard and some minerals and vitamins (546 kcal/100 g diet - calorically and macrowise this looks much like chocolate and candy bars to me ;-) and end up not just exactly as lean, but even a little leaner than your peers on a "healthy" after two years of gluttony? Sounds crazy? Yeah, but it worked!

In the latest study from the Ehime University Graduate School of Medicine in Japan (Sumiyoshi. 2013), the scientists demonstrated that 20 weeks on the previously described high fat diet (if you use the rule of thumb that a mouse year equals 40 human years this would be the aforementioned 2 years).
Figure 1:Body weight trajectory and micrographs of the adipose tissue (Sumiyoshi. 2013)
Not being fat on the outside and, even more, having a regular weight on the scale is yet only the superficial clue to a more subtle, yet highly important internal difference: the fat cell size. With the hop extracts ability to inhibit lipid accumulation within adipose tissue cells by down-regulating our new acquaintance PPAR-gamma (see "PPARs - High or Low? How Are They Supposed to Be?", red box) and thus blocking both their expansion and their proliferation, the mice in the male C57BL/6J and Balb/c mice in the hop extract groups did in fact end up with less visceral body fat than their peers on the regular chow:
Figure 2: Organ weights (rel. to group on standard chow) and blood glucose clearance in OGGT (Sumiyoshi. 2013)
And if that's not enough as far as good news are concerned, their insulin sensitivity and ability to clear glucose from the blood stream was not compromised, either. In this context, it is also worth mentioning that the hop water extract had no effect on faecal fat excretion in mice fed a HF diet (in vivo), and pancreatic lipase activity (in vitro). In other words, the remarkable results were not simply the result of an inhibition of fat absorption.

Do you remember Rhein the natural PPAR-gamma antagonist in Rhubarb? No? Then I suggested you go back in the archives and (re-)read the respective article. You will be surprised how similar the results were... a total amelioration of the HFD induced weight gain, normal body fat levels and no insulin resistance - sounds familiar, no?
Bottom line: So, just as the scientists point out in their discussion of the results, the main mechanism behind this miraculous anti-obesity effects is the suppression of the HFD induced increases in PPAR-gamma activity. Against that background it appears ridiculous that already overweight, often obese diabetics and pre-diabetics are still treated with thiazolidinediones including pioglitazone and rosiglitazone (all PPAR-gamma agonists), which 'improve' insulin sensitivity by allowing the adipose organ to proliferate via adipocyte differentiation and increases in lipid and glucose uptake, and fatty acid storage.

According to the researchers, "[e]xperiments are now in progress to isolate the active substance(s) of hop extract". However, we all know that once this substance is found, the "logical" (actually this is business, not real logic) next step is to add a twist that turns it into a patentable not naturally occurring molecule and make counterproductive and (business logic) no longer really profitable PPAR-gamma agonists with another drug.

References:
  • Sumiyoshi M, Kimura Y. Hop (Humulus lupulus L.) extract inhibits obesity in mice fed a high-fat diet over the long term. Br J Nutr. 2013 Jan;109(1):162-72.

Wednesday, December 26, 2012

Seabuckthorn Leaves Increase PPAR-Alpha & PPAR-Gamma Expression, Keep the Liver Fat Free and Fatty Oxidation Up. Plus: PPARs - High or Low? How Are They Supposed to Be?

This time, the magic is in the leaves, not the fruits or kernels. And it's dose dependent. With an almost linear increase from 500-1,000mg/kg
Honestly, I don't think that it is coincidence that many of the most promising medical plants are shrubs that live on barren soil, like sand dunes and cliffs and are full of thorns as well as innate polyphenolic defense mechanisms. Whatever the "evolutionary" basis may be, if we go by the beneficial metabolic effects, researchers from the Department of Food Science and Human Nutrition at the Chonbuk National University in the Republic of Korea, it appears worth going through all the traditional used folk medicine across the world and identify which of them work, how they work and whether they may already have what it takes to get rid of one or the other of the typical Western diseases.

In the case of the ethanolic extract of seabuckthorn (Hippophae rhamnoides L) Pichiah et al. used in their most recent experiment, this would be ameliorative effects on weight gain through down-regulation of adipogenic and lipogenic gene expression.

Less weight gain more fatty acid turnover, better glucose management and leptin sensitivity

The ameliorative effects on the detoriation of glucose metabolism, the reduced but still significant weight gain of the 60% fat diet (additional fat 100% from lard) and the profound overexpression of leptin, which is indicative of the fact that the mice developed full-blown leptin resistance within the 13-weeks of HFD administration, were all ameliorated to a greater degree in the high dose seabuckthorn leaf extract group (human equivalent  ~6.5g/day).
Figure 1: Effect of the different diets on weight gain, visceral fat weight, feed intake and energy intake (left; data expressed relative to control diet); effects on blood sugar (AUC in glucose tolerance test) and leptin (Pichiah. 2012)
The differences between high and low dose supplementation of the extract which had been prepared by
"[...] by soaking the dried, powdered leaves in 70% ethanol for 7 days at room temperature. Then the extract was concentrated by evaporating ethanol using a rotary vacuum evaporator (N-N Series, EYELA, Tokyo, JAPAN) set at 60°C and 100 hPa" (Pichiah. 2012)
were even more pronounced, when we compare the effects on fatty acid oxidation (CPT-1), the PPAR-alpha and -gamma values.
Figure 2: Carnitine palmitoyltransferase I (CPT1), PPAR-alpha & -gamma activity and triglyceride & cholesterol content in the liver (left; expressed relative to rodents on normal chow). Histology of liver sections at 200x magnification for the different diets (Pichiah. 2012)
What's yet most striking is however that the liver - the organ that's so heavily involved in the etiology of insulin resistance - was virtually "fat-free" in the rodents who received the 1,000mg/day dose. The total triglyceride and cholesterol content was even lower than in the mice on the normal diet and the overall darker staining in the slices on the right of figure 2 is only further evidence of the beneficial effects the seabuckthorn extract had on the liver histology.
The effects of a 5% conjugated linoleic acid diet do actually resemble that of lipodystrophy, i.e. pathological fat loss and inability to store body fat. Strange, no? Well that's PPAR-gamma (read more).
PPAR-gamma? Wasn't that what you actually wanted to avoid? In a way this is right, since PPAR-gamma and even alpha are somewhat Janus-faced molecules (overview for PPAR-alpha). As beneficial as their expression in the liver may be, both inhibit the oxidation of glucose. PPAR-gamma is also involved in the maturation process from pre-adipocytes to mature adipocytes, increases lipogenesis in white adipose tissues, decreases the cell surface fatty acid transporter on muscle cells and increases glucose uptake in adipocytes (exclusively). All that is healthier than fat clogging your liver, but it's not exactly something that will make you leaner if you are work out and consume a junk-free diet.

In fact, the PPAR-gamma suppressing effects of the trans-10, cis-12 isomer of conjugated linoleic acid (CLA; cf. Kennedy. 2008) are actually what what produces such profound effects, as they were observed in the study I discussed on July 22, 2012 (see link beneath the image of the mice).

TTA and fish oil are potent antagonists of liver PPAR expression. With the uncoupling and anti-inflammatory effects of TTA being the key to unleash & maintain fat-burning (read more).
Bottom line: It appears as if the liver is - once again - emerging as a central player in "sick obesity", meaning being fat and sick and not just fat. Which reminds me of yesterday's post on Gluten and the development of metabolic disease, where fatness is no criteria, at all. The expression of the "liver cleansing" PPAR-gamma enzymes on the other hand was.

This in turn reminds me of the effects of fish oil and TTA (a pan PPAR-activator), which - despite their questionable use as a long-term intervention can in fact stimulate intra-hepatic fatty acid oxidation to levels which are so high that oxidation rates in and out of itself could bring about some problems.

Other nutritional factors you should take into account are choline (a deficiency will actually cause fatty liver disease; read more about choline) or taurine. And on the endocrine side of things you want to keep an eye on optimal DHEA levels (read more about its effects on PPAR-gamma), thyroid hormones, testosterone and estrogen (Nemoto. 2000).

References
  • Kennedy A, Chung S, LaPoint K, Fabiyi O, McIntosh MK. Trans-10, cis-12 conjugated linoleic acid antagonizes ligand-dependent PPARgamma activity in primary cultures of human adipocytes. J Nutr. 2008 Mar;138(3):455-61.
  • Nemoto Y, Toda K, Ono M, Fujikawa-Adachi K, Saibara T, Onishi S, Enzan H, Okada T, Shizuta Y. Altered expression of fatty acid-metabolizing enzymes in aromatase-deficient mice. J Clin Invest. 2000 Jun;105(12):1819-25.
  • Pichiah PB, Moon HJ, Park JE, Moon YJ, Cha YS. Ethanolic extract of seabuckthorn (Hippophae rhamnoides L) prevents high-fat diet-induced obesity in mice through down-regulation of adipogenic and lipogenic gene expression. Nutr Res. 2012 Nov;32(11):856-64.