|Image 1: I've got news for you: Real coffee does not come in brown sterophome cups ;-)|
Live longer, live leaner and live diabetes-free with...coffee!
I guess, some of you will probably remember my pre-Christmas blogpost on the "Anti-Diabesity Effects of Coffee", in which I elaborated on the results of a recently published paper by Matsuda et al. who observed significant reductions in weight gain in rodents receiving either diluted coffee or pure caffeine in addition to a fattening high fat (+high carb) diet. Contrary to the body weight gain, which was ameliorated about equally effective by both treatments, the "whole coffee" treatment had a much more pronounced effect on the particularly unhealthy visceral fat in the epididymal area (cf. previous news, figure 2).
|Figure 1: Molecular structure of chlorogenic and caffeic acid, two of the major phenolic compounds in coffee beans (adapted from Tsuda. 2012)|
In view of the fact that cacao, just like coffee contains both chlorogenic and caffeic acid (Duke. 2000), it is almost certain that the health benefits which have been ascribed to the consumption of phenol rich dark chocolate within the last couple of years can be traced back to increases in skeletal muscle AMPK-phosphorylation, as well.To prove their hypothesis that caffeic acid and / or chlorogenic acid act directly on the AMPK-pathway in skeletal muscle, the scientists incubated isolated rat epitrochlearis muscles with different amounts of the coffee phenols and measured the phosphorylation of AMPKα Thr172 and ACC Ser79
|Figure 2: Relative AMPK-phosphorylation in isolated rat epitrochlearis muscles in response to incubation with 0.01, 0.1 and 1mM of chologenic and caffeic acid (left); relative increase in AMPK-phosophorylation after incubation with 1mM of caffeic acid for 5, 15, 30 and 60 min (right; data adapted from Tsuda. 2012)|
|Figure 3: Relative increase in AMPK isoform phosophorylation (left) and increase in glucose transport measured with 3O-methyl-glucose as a marker (right) in skeletal muscle of rats after incubation with 1mM of caffeic acid for 30 min ( data adapted from Tsuda. 2012)|
|Figure 4: Relative amounts of ATP and phosphocreatine (PCr) and phosphorylated AKT in skeletal muscle after incubation with 1mM of caffeic acid for 30 min (data adapted from Tsuda. 2012)|
Caffeic acid won't decrease protein synthesis, but could reduce the effectiveness of creatine
And while Tsuda et al. mention the detrimental effect caffeic acid exerts on intra-muscular phosphocreatine stores in the discussion of the results, they are not able fully explain this observation which reminds me of the old "myth" that the caffeine in coffee would compromise the beneficial effects of creatine supplementation... I guess we have just found why some studies did in fact support this hypothesis. If the caffeic acid induced increase in AMPK-phosphorylation goes hand in hand with a reduction in the amount of stored creatine phosphate (PCr), this could mean that you would need more creatine to achieve and maintain "maximal" levels of this high-performance energy reserve.
As you can see, it is always the same, with every question we answer a new one arises. What did Socrates say? Yeah: "I know that I know nothing!" I suppose this is a good concluding word for today's blogpost. Come back tomorrow if you want to know what else you do not know ;-)