Glutamine is the most abundant amino acid in the blood and is an important source of energy for many tissues in the body. It is derived from the amino acids histidine and glutamic acid. Glutamine improves immune function, balances ammonia in the body, contributes to biosynthesis of proteins, amino acids, nucleic acids, glutathione, glutamate, and GABA.

- Glutamine is a conditionally essential amino acid (conditional mainly during times of disease or muscle wasting, such HIV/AIDS, cancer, or severe infections).

- In the intestinal lining, glutamine is the preferred source of fuel for intestinal epithelial cells and the main energy source for leukocytes (immune cells).

- Other important functions of glutamine include: transporting nitrogen between cells, acting as a precursor to glutathione production, acting as a precursor to nucleotides (for DNA and RNA synthesis), participating in gluconeogenesis in the absence of adequate carbohydrate intake, blunting the rise of blood glucose after consuming carbohydrate-rich meals, and regulating intestinal tight junctions.

Very good sources of glutamine include: whey, casein, milk, white rice, corn, and tofu.

Good sources of glutamine include: meat and eggs.

- Glutamic acid has been associated with higher BMI, blood pressure, and insulin resistance, while glutamine levels were inversely associated.

- A high plasma glutamine-to-glutamic acid ratio was associated with lower risk of diabetes in the Framingham Heart Study (n=1015).

- Higher glutamine-to-glutamic acid ratio was associated with a better cardiometabolic-risk profile over 10 years in the PRIMED study (n=1879).

- Glutamic acid has been associated with higher BMI, blood pressure, and insulin resistance, while glutamine levels were inversely associated.

- A high plasma glutamine-to-glutamic acid ratio was associated with lower risk of diabetes in the Framingham Heart Study (n=1015).

- Higher glutamine-to-glutamic acid ratio was associated with a better cardiometabolic-risk profile over 10 years in the PRIMED study (n=1879).

Glutarate (Glutaric Acid) is formed from the essential amino acids lysine and tryptophan through the intermediaries of alpha ketoadipic acid and glutaryl-CoA. Glutaryl-CoA is further metabolized to glutaconyl- and crotonyl-CoA by an enzyme called glutaryl-CoA dehydrogenase. This enzyme requires riboflavin (vitamin B2) as a cofactor.

Glutaric acid is made from lysine & tryptophan via alphaketo-adipic acid.

- Elevated in the genetic diseases glutaric academia types I and II.
- Moderate increases may be due to deficiencies in riboflavin and coenzyme Q10, or celiac disease.
- Moderate increases are common in autism possibly due to defective vitamin absorption or microbial production in the GI tract.

Glutaric acid is made from lysine & tryptophan via alphaketo-adipic acid.

- Elevated in the genetic diseases glutaric academia types I and II.
- Moderate increases may be due to deficiencies in riboflavin and coenzyme Q10, or celiac disease.
- Moderate increases are common in autism possibly due to defective vitamin absorption or microbial production in the GI tract.

Glutaric acid is made from lysine & tryptophan via alphaketo-adipic acid.

- Elevated in the genetic diseases glutaric academia types I and II.
- Moderate increases may be due to deficiencies in riboflavin and coenzyme Q10, or celiac disease.
- Moderate increases are common in autism possibly due to defective vitamin absorption or microbial production in the GI tract.

Glutaric acid is made from lysine & tryptophan via alphaketo-adipic acid.

- Elevated in the genetic diseases glutaric academia types I and II.
- Moderate increases may be due to deficiencies in riboflavin and coenzyme Q10, or celiac disease.
- Moderate increases are common in autism possibly due to defective vitamin absorption or microbial production in the GI tract.

Glutaric acid is a breakdown product of lysine and/or tryptophan.

Glutaric Acid is formed from the essential amino acids lysine and tryptophan through the intermediaries of alpha ketoadipic acid and glutaryl-CoA. Glutaryl-CoA is further metabolized to glutaconyl- and crotonyl-CoA by an enzyme called glutaryl-CoA dehydrogenase. This enzyme requires riboflavin (vitamin B2) as a cofactor.

Glutaric Acid (Glutarate) is endogenously produced in the catabolism of lysine and tryptophan.

- Increased Glutaric acid is associated with secondary carnitine deficiency.

- Glutaryl-CoA (from lysine or tryptophan) normally enters the Krebs cycle via transition to acetyl-CoA.

    » Glutaryl-CoA dehydrogenase (GCDH) + glutaryl-CoA + B2 → acetyl-CoA.

    » If GCDH is blocked, glutaryl-CoA + carnitine → elevated glutaric acid.

Glutaric Acid is formed from the essential amino acids lysine and tryptophan through the intermediaries of alpha ketoadipic acid and glutaryl-CoA. Glutaryl-CoA is further metabolized to glutaconyl- and crotonyl-CoA by an enzyme called glutaryl-CoA dehydrogenase. This enzyme requires riboflavin (vitamin B2) as a cofactor.

Glutaric Acid is formed from the essential amino acids lysine and tryptophan through the intermediaries of alpha ketoadipic acid and glutaryl-CoA. Glutaryl-CoA is further metabolized to glutaconyl- and crotonyl-CoA by an enzyme called glutaryl-CoA dehydrogenase. This enzyme requires riboflavin (vitamin B2) as a cofactor.

Glutathione is implicated in many cellular functions including antioxidant protection and detoxification. It is also essential for the maintenance of cell membrane integrity in red blood cells.

Glutathione (GSH) is a tripeptide comprised of three amino acids (cysteine, glycine, and glutamic acid). Glutathione is the body’s most potent intracellular antioxidant. It exists intracellularly in either an oxidized or reduced state.

GSH acts as an antioxidant, free radical scavenger, and detoxifying agent. Excessive formation of reactive oxygen species (ROS), including hydrogen peroxide (H2O2), is toxic to the cell. Hence, the metabolism of these free radicals are critical, and they are tightly controlled. [L]