Branched-chain amino acids are elevated in diabetic kidney disease and are associated with insulin resistance and podocyte injury through mTORC1 activation, while sulfur-containing amino acid metabolism is impaired, leading to reduced hydrogen sulfide production and increased homocysteine levels that promote vascular damage.

In diabetic kidney disease, excess branched-chain amino acids overactivate a cellular growth switch called mTORC1, which blocks insulin signaling in kidney cells and stops the cleanup of damaged parts, leading to cell death. At the same time, the body makes less hydrogen sulfide because key enzymes break down, leaving the kidneys vulnerable to damage. This loss of protection, combined with a buildup of toxic waste from gut bacteria, causes inflammation, oxidative stress, and blood vessel harm.