Leucine - More Who Take It

Summary: resveratrol doses with leucine increased skeletal muscle
and adipocyte Sirt1 activity, mitochondrial biogenesis and fatty acid
oxidation

6 Nov 2020h Modulation of Energy Sensing by Leucine Synergy with Natural Sirtuin
Activators: Effects on Health Span; Michael B. Zemelps://doi.org/10.1089/jmf.2020.0105
Abstract
Sirt1 and 5′ adenosine monophosphate-activated protein kinase (AMPK) are
energy-sensing systems that work cooperatively and regulate
mitochondrial biogenesis and fuel metabolism, and mediate, in part, the
salutary effects of caloric restriction on lifespan and healthspan. We
have shown that leucine activates Sirt1 and enables synergy with sirtuin
co-activators. Resveratrol is a widely recognized activator of Sirt1;
however, poor bioavailability and rapid metabolism limit effective
clinical translation of promising animal data. However, we found that
combining low resveratrol doses with leucine increased skeletal muscle
and adipocyte Sirt1 activity, mitochondrial biogenesis and fatty acid
oxidation; these effects result in increased lifespan and marked
reductions in insulin resistance, inflammatory markers, body weight, and
visceral adiposity in preclinical models.

Ken - I too have avoided Leucine like the plague for the past several years. After reading the article on the possible catabolic effects of leucine I’ve decided to give it a try.  I haven’t decided, however, whether to take the full 1.1 gram/2x daily dose that was used in the study or a smaller one. Of course I would like to see further research showing the safety (the lack of Mtor) of taking small doses of leucine.  Unfortunately I have no way of measuring its catabolic or anabolic effects.

Small amounts are associated with catabolic effects, while larger amounts activate mTOR with resulting anabolic effects. In other words there seems to be a U shaped function with small amounts triggering catabolic effects and large amounts anabolic effects. The authors used 1.11 grams of leucine 2x daily, or a little over two grams/day to achieve catabolic effects. Contrast this with the significantly larger amounts that athletes take for its anabolic effects. For example, the label of a jar of leucine that I have recommends taking 5 grams when training for its anti-catabolic effects and to enhance protein synthesis. From Ken at GRG: For several years now since I discovered studies showing that leucine is a major promoter of mTOR, I have tried to avoid it, but this study suggests that I should be taking it again (as part of a branched chain amino acid supplement).