In healthy young adults, high insulin levels alone, without additional amino acids, do not improve the mitochondria's ability to produce energy, even though genes related to mitochondria become more...
Mechanism
Synthesis from 1 study
High insulin tells muscle cells to make more energy factories, but without enough amino acids, the cells can't build them. Even though the instructions to build are turned up, the parts never get assembled, so energy production stays the same.
Most probable mechanism
When insulin levels stay high but there aren't enough amino acids available, the body turns on genes that should make more energy-producing parts in muscle cells, but it can't actually build those parts because it's missing the raw materials. Without those materials, the signal to start building proteins gets stuck, so the energy factories don't get bigger or work better, even though the instructions to build them are turned up.
Insulin binding to muscle cell receptors activates the PI3K-Akt signaling pathway, increasing phosphorylation of Akt
Low availability of essential amino acids, particularly branched-chain amino acids, prevents activation of the mTORC1 complex despite Akt activation
Inactive mTORC1 fails to phosphorylate downstream translational regulators p70S6K and 4EBP1, halting the initiation of protein synthesis
Reduced mitochondrial protein synthesis limits the replacement and assembly of respiratory chain components, preventing increases in enzyme activities and ATP production
Transcriptional upregulation of mitochondrial genes (e.g., PGC-1α, NRF1, COX III) occurs independently but does not translate into increased protein content or functional output without concurrent translational activation
Evidence from Studies
Supporting (1)
Community contributions welcome
Insulin fails to enhance mTOR phosphorylation, mitochondrial protein synthesis, and ATP production in human skeletal muscle without amino acid replacement.
Contradicting (0)
Community contributions welcome
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.