Amino Acids: Metabolism, Functions, and Their Role in Health and  Disease Management

Rand Thair Abdul-kader

doi:10.61132/obat.v3i4.1432

Authors

Rand Thair Abdul-kader Al-karkh university of Science

DOI:

https://doi.org/10.61132/obat.v3i4.1432

Keywords:

Amino Acids, Branched-Chain Amino Acids, Cancer Treatment, Diseases, Insulin Resistance, Metabolic Health

Abstract

Abstract. Amino acids are indispensable components of human metabolism, playing essential roles in protein
synthesis, energy production, and cellular regulation. Branched-chain amino acids (BCAAs)-leucine, isoleucine,
and valine—are particularly significant due to their involvement in muscle repair, metabolic signaling, and
insulin sensitivity. While BCAAs are vital under normal physiological conditions, multiple studies have shown
that elevated plasma BCAA levels are linked to insulin resistance, obesity, and type 2 diabetes. This association
has led researchers to investigate whether these elevations are a cause or consequence of metabolic
dysfunction. Recent findings have revealed that impaired BCAA catabolism in tissues such as adipose and liver
contributes to their accumulation in circulation. If skeletal muscle becomes insulin resistant, it may shift BCAA
metabolism further, exacerbating the imbalance. Moreover, the modulation of specific enzymes and transporters
has been proposed as a therapeutic avenue to mimic the beneficial effects of dietary protein restriction.
Although several mechanisms have been proposed, including mTOR activation, fatty acid oxidation
interference, and altered neurotransmitter synthesis, no single pathway fully explains BCAA-induced metabolic
disturbances. Therefore, a comprehensive understanding of amino acid metabolism is crucial, particularly if
dietary and pharmacological interventions are to be optimized for preventing or treating age-related and
metabolic diseases.

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