Green tea antioxidants EGCG and its influence on myostatin

Bodybuilders and most strength athletes in general, tend to focus almost exclusively on the importance of macronutrients. Indeed, while dietary intake of protein, carbohydrates and fats is essential for energy release and muscle growth, micronutrients are just as important. By now, who doesn't know that minerals such as magnesium or zinc are critically important when it comes to releasing testosterone or to generate energy? This is just as true for vitamins and their role in most metabolic processes in the human body. This is especially true for B vitamins and vitamin D, for example. Vitamin B2 and B3 are also precursors of coenzymes such as FAD and NAD+, without which cellular life would be impossible. But what is really happening with antioxidants, the molecules we classify as secondary metabolites?

Secondary metabolites are complex molecules that do not have a direct role in metabolism.

Secondary metabolites do not, strictly speaking, have a direct role in our metabolism or in a majority of processes essential to our survival. However, they indirectly contribute to our daily health, as well as to our longevity. This is all the more true since they are very numerous; we currently count a little more than 10,000. Today, we classify them according to their family and subfamily, into polyphenols, flavones, flavonoids or other flavonols. While they are countless, we know a little over 600 polyphenols as well as their roles and interactions for some of them. We are therefore very far from understanding everything about these complex molecules on a scientific level. If we are quick to assert that they all act as cellular antioxidants, which is more or less accurate, their biological functions and their influence on the body are much more varied and diverse.

Let's just say that when it comes to antioxidants, some of them are remarkable. Examples include OPCs from grape seeds, hydroxytyrosol and oleuropein from olive oil, EGCG polyphenols from green tea or quercetin capers and red onion. As you know, it's not just about antioxidants, since OPCs thin the blood, or oleuropein and quercetin have antiviral and antibacterial effects that are well known in medicine. We can clearly see that some of these antioxidant secondary metabolites have properties that could be of interest to bodybuilders, for example for OPCs but also for EGCG in green tea, and for a very specific reason...

EGCG, polyphenols from green tea, are of interest to bodybuilders for certain very specific properties

Green tea polyphenols are known for their supposed health benefits, beyond their antioxidant potential. Some animal and clinical studies claim that EGCG from tea Green tea (epigallocatechin gallate) and its catechins more generally, contribute to health, slimness, reduce the risk of several types of cancer, moderate blood sugar levels and improve longevity. For bodybuilders, the consumption of green tea is equally interesting. While green tea is known to moderate the release of cortisol (the stress hormone and accelerated catabolism) and to facilitate post-exercise recovery, the EGCG in green tea has another essential property for bodybuilders: reducing the presence of myostatin.

Myostatin, a metabolic regulatory protein that inhibits muscle growth

As you may know, myostatin is a protein from the myokine category (cellular messenger present in muscles) whose function is to moderate the muscle growth so that it remains functional. Follistatin, on the other hand, stimulates protein synthesis. This balance between myostatin and follistatin is of paramount importance for the normal functioning of our muscles. A deficiency in myostatin or an excess of follistatin would have adverse consequences on muscle functionality. However, it is always worth considering the possibility that myostatin could be less present and thus promote anabolism and muscle growth. To this end, certain perfectly natural substances tend to slow down myostatin. These are creatine, leucine and HMB, the metabolite derived from leucine. This isn't particularly surprising. But what about the EGCG in green tea?

Animal studies demonstrate the influence of EGCG on myostatin and other growth factors

Two animal studies suggest that green tea EGCGs have a beneficial effect on muscle growth, particularly on myostatin. The study by Chang (2020) and colleagues provides relevant evidence to this effect. EGCGs also appear to restore the activity of Akt, a myokine closely linked to muscle protein synthesis. Similarly, a 2015 study by Meador and colleagues suggests that green tea polyphenols, and EGCGs in particular, may be able to mitigate sarcopenia-related muscle atrophy in aged animal models. In this study, too, the researchers suggest that myostatin may be involved, along with other growth factors, including IGF-1 and IL-15, both of which are involved in maintaining muscle mass. Moreover, Gutierrez-Salmean's 2013 study was one of the first experiments to highlight the role of epicatechin on the stimulation of growth factors and the moderation of myostatin.

YAM Nutrition

Bibliography elements

• Chang YC et al. The green tea polyphenol epigallocatechin-3-gallate attenuates age-associated muscle loss via regulation of miR-486-5p and myostatin, Arch Biochem Biophys. 2020 Oct 15;692:108511.
• Gutierrez-Salmean G, Ciaraldi TP, Nogueira L, Barboza J, Taub PR, Hogan M, Henry RR, Meaney E, Villarreal F, Ceballos G, Ramirez-Sanchez I. Effects of (-)-epicatechin on molecular modulators of skeletal muscle growth and differentiation . Journal of Nutritional Biochemistry. Oct. 2013.
• Meador BM Et al. The Green Tea Polyphenol Epigallocatechin-3-Gallate (EGCg) Attenuates Skeletal Muscle Atrophy in a Rat Model of Sarcopenia , J. Frailty Aging, 2015;4(4):209-15.
• Saremi A., Effects of oral creatine and resistance training on serum myostatin and GASP-1 , Moll. Cell. Endocrinol. 2010 Apr 12;317(1-2):25-30.