So now it appears that leucine is bad too. And... almost ALL the legumes (black beans, lentils, soybeans, etc) are VERY high in leucine (the leucine content is higher than the content for most of the other amino acids). Even quinoa is comparatively high in leucine.
So now what? Am I screwed?
Ugh, even oatmeal. http://nutritiondata...-cereals/1598/2
From the CR Society Mailing List:
The below paper is not pdf-availed (free full-text?) for 3 months.
Leucine Deprivation Increases Hepatic Insulin Sensitivity via GCN2/mTOR/S6K1 and AMPK Pathways.
Xiao F, Huang Z, Li H, Yu J, Wang C, Chen S, Meng Q, Cheng Y, Gao X, Li J, Liu Y, Guo F.
Diabetes. 2011 Mar;60(3):746-56. Epub 2011 Jan 31.
We have previously shown that serum insulin levels decrease threefold and blood glucose levels remain normal in mice fed a leucine-deficient diet, suggesting increased insulin sensitivity. The goal of the current study is to investigate this possibility and elucidate the underlying cellular mechanisms.
RESEARCH DESIGN AND METHODS
Changes in metabolic parameters and expression of genes and proteins involved in regulation of insulin sensitivity were analyzed in mice, human HepG2 cells, and mouse primary hepatocytes under leucine deprivation.
We show that leucine deprivation improves hepatic insulin sensitivity by sequentially activating general control nonderepressible (GCN)2 and decreasing mammalian target of rapamycin/S6K1 signaling. In addition, we show that activation of AMP-activated protein kinase also contributes to leucine deprivation-increased hepatic insulin sensitivity. Finally, we show that leucine deprivation improves insulin sensitivity under insulin-resistant conditions.
This study describes mechanisms underlying increased hepatic insulin sensitivity under leucine deprivation. Furthermore, we demonstrate a novel function for GCN2 in the regulation of insulin sensitivity. These observations provide a rationale for short-term dietary restriction of leucine for the treatment of insulin resistance and associated metabolic diseases.
-- Al Pater, alpater@SHAW.ca
Thanks for this important reminder, Al, about how leucine stimulates mTOR.
Although this has been discussed in the past, I imagine there are a fair
number of new Society members who haven't seen research on the mTOR-leucine
theme and make want to rethink their intake of foods like whey that are high
Edited by InquilineKea, 08 March 2011 - 08:02 PM.