Wednesday, November 6, 2013

4g of Conjugated Linoleic Acid Promote CYP17A1 + Leydig Cell Testosterone Production and Increase Cardio-Mediated Muscle, Strength and Endurance Gains

"That's all the exercise in induced T-response, bro. Now shut up, I got to squat!"
Yes, this is another of those rodent studies of which we simply don't know if the results will eventually translate to humans. In contrast to previous studies on CLA, which dealt with weight loss and produced marvelous results (see "CLA Destroys Body Fat & Increases Endurance!" | read more) which could not be reproduced in human trials.

This very recent paper from Italy deals with CLA's effects on exercise, testosterone, and potential gains in muscle mass and leaves the parameter body fat out of the equation (Barone. 2013).

"Hold on, that's not news, is it?"

When Roy Nelson shot me the link to the pertinent paper by Rosario Barone et al. (2013), the above, i.e. "Hold on, that's not news, is it?" was actually my first thought. After all, I had written about the purported muscle building effects of CLA in the past (see "Review Claims: CLA & Fish Oil Improve "Anabolic" Effects of Exercise - What Does the SuppVersity Sniff Test Say?" | read more). After briefly checking my previous article, I did realize, though: This is news!

The previous article did not discuss the same results. It did however come from the same team of Italian researches and made the claim that CLA & fish oil would be natural anabolics (read it!) - a claim I reviewed and wrote:
"[...] as far as ergogenic and/or anabolic effects are concerned, CLA is unquestionably the more promising fatty acid off the "two" (actually we are talking about four fatty acids, here: DHA + EPA = fish oil and cis-9,trans-11 and trans-10,cis-12 CLA)." (SuppVersity. 2013)
I have to admit, though, that I was thinking of CLA's ability to block the storage of body fat on a bulk, primarily - not so much about its not yet fully, but at least half-way established effects on exercise performance. The testosterone boosting effects, on the other hand, were something I discarded, so that it's about time to look at them more closely.

In vitro + in vivo - that's the way Barone et al. did it

In a first attempt to access the effects of CLA on the testicular androgen production, the scientists from the University and Hospital of Palermo conducted a couple of tests in the petri dish. Usually boring stuff, if it were not for geeks like me (and some of you) who always ask the nasty question: "Why".

Figure 1: The same research group published a paper that showed increased testosterone in young men on a resistance training regimen. It is therefore not totally unlikely that the results do translate to human beings; the figure shows the total testosterone before vs. after a workout in ng/dl (Macaluso. 2012)
In this case, we are lucky, because Barone et al. did not focus solely on the amount of steroids the the leydig tumour cells (don't worry that should work with regular cells, as well) were spilling out. They also tested for enzymatic changes and observed that as 17α-hydroxylase/17,20-lyase (CYP17A1), which converts progesterone into androstenedione and has  been demonstrated to have direct downstream effects on the testosterone production (Svechnikov. 2009; Weisser. 2011).

As every SuppVersity reader knows, the cytochrome P450 enzyme cascade is on of the most powerful and overlooked actors in the steroid orchestrate. While CYP17A1, which does effectively increase the production of testosterone pre-cursors and will thus exert an indirect beneficial effect on the testosterone production, other members of the cytochrome family facilitate the conversion and clearance of testosterone.

Against that background it was sound to expect to observe similar effects in the in-vivo part of the study. The interplay with other enzymes, however, could easily have thwarted the results. Outside of the petri dish the sheer number of variables that could change the outcome of the study makes it more or less impossible to predict the "exact" study outcome and - I want to emphasize this - the latter could well look slightly or completely different from what you see in Figure 2, when you went ahead and tried to support your training efforts with 4g of the patented Tonalin® FFA 80:
Figure 2: Free testosterone and CYP17A1 expression in the supplemented (CLA-) /  unsupplemented (PLA-) mice after 6 weeks of no (SED) or 15-60min (ramp up) of exercise 5x per week (Barone. 2013).
I hope you did notice the important hint I hid in the last sentence above Figure 2, where it says: "Support your training efforts..." If you didn't take a look at Figure 2 ... I guess, it's obvious to see that this short insert is of paramount importance: No training, no CLA bonus!
"The protein expression of CYP17A1 was significantly higher in both the trained groups (PLA-TR and CLA-TR) compared to the sedentary groups (PLA-SED and CLA-SED) (P <0.01). Moreover, CLA supplementation induced a further increase in CYP17A1 protein in the CLA-TR group compared to the PLA-TR group (P < 0.01)" (Barone. 2013)
In other words, training alone is a CYP17A1 powered testosterone booster and CLA is an adjuvant, which has no effect in the absence of 6 weeks with five "cardio" sessions/week at an ever-increasing pace and duration (15-60min and 3.2-4.8m/min from week 1-6).
Figure 4: Body weight gain, and force/body weight gain  (in %; top) and distance traveled relative to SED-PLA group (Barone. 2013)
"Wow that's exciting, isn't it?" Actually no - not really. The increase in testosterone alone would hardly be worth the paper this article is probably never going to be printed on. What is at least borderline exciting, though, are the increase in muscle gains, strength and running distance the rodents covered in a standardized test (see Figure 3).

Yeah, I have to admit: The data does look exciting, but that can be said of the previously referenced study by Macaluso, as well. The said human trial (see Figure 1), however, tells us that it's probably unrealistic to expect similarly pronounced effects with even more CLA (6g in the Macaluso study from 2012) in men.

Personally, I would save the money, but if you want to try it: Go ahead... and tell us if it works ;-)

I, for my part, am missing anecdotal evidence (You can't tell me that there is no one who has tried that already - so where are the "CLA is king, bro!" posts on the various boards?), the confirmation of this or at least similar effects by other scientists and a 'Conflict of Interest' declaration at the end of a paper that puts such an emphasis on the "®" in  Tonalin® FFA 80.

  • Barone, R, Macaluso F, Catanese P, Marino Gammazza A, Rizzuto L, et al. Endurance Exercise and Conjugated Linoleic Acid (CLA) Supplementation Up-Regulate CYP17A1 and Stimulate Testosterone Biosynthesis.  PLoS ONE 8(11): e79686.
  • Macaluso F, Morici G, Catanese P, Ardizzone NM, Marino Gammazza A, Bonsignore G, Lo Giudice G, Stampone T, Barone R, Farina F, Di Felice V. Effect of conjugated linoleic acid on testosterone levels in vitro and in vivo after an acute bout of resistance exercise. J Strength Cond Res. 2012 Jun;26(6):1667-74.
  • Svechnikov K, Spatafora C, Svechnikova I, Tringali C, Söder O. Effects of resveratrol analogs on steroidogenesis and mitochondrial function in rat Leydig cells in vitro. J Appl Toxicol. 2009 Nov;29(8):673-80.
  • Weisser J, Landreh L, Söder O, Svechnikov K. Steroidogenesis and steroidogenic gene expression in postnatal fetal rat Leydig cells. Mol Cell Endocrinol. 2011 Jul 20;341(1-2):18-24. doi: 10.1016/j.mce.2011.03.008.