Health Benefits Of Valine

Graphic © herbshealthhappiness.com

Valine is a nonpolar proteinogenic amino acid with stimulant activities and wide applications in pharmaceutical and food industries. It is part of a trio, along with leucine and isoleucine, of branched-chain amino acids that comprise approximately 70% of the amino acid content in the proteins of the body, making the three very vital to the preservation of structural and functional integrity in humans. Furthermore, valine is an essential amino acid that the human body cannot naturally synthesize and thus must be obtained through consumption of various food sources such as pork loin, turkey, egg white, chicken, seaweed, soybeans, and Swiss cheese. [1] Valine deficiency is considered rare since most protein-rich foods contain substantial quantities of branched-chain amino acids; vegetarians and people on diets consisting of extremely low amounts of protein are groups at risk of deficiency hence.

Valine closely resembles the structure, functions, and characteristics of its branched-chain brothers, leucine and isoleucine. The three are extremely hydrophobic and are nearly always found in the interior of proteins where they determine the three-dimensional structure of proteins. [2]

Valine and Its Functions

Valine is among the compounds involved in muscle growth and tissue repair and is a precursor in the penicillin biosynthetic pathway. Its functions include enhancing energy and endurance, decreasing elevated blood sugar levels, increasing growth hormone production, and promoting nitrogen balance in adults, among others. [3]

Valine and Muscle Damage and Fatigue

Valine contributes to the maintenance of muscles by preventing too much breakdown of muscle proteins during strenuous physical activities and conserving muscle glycogen stores, which can be later converted into energy when the need arises. [2] A number of studies have revealed that valine as part of the branched-chain trio may lessen the damage to muscles induced by exercise and promote recovery from such damage. The study results of Shimomura et al. (2006) demonstrated that supplementation of branched-chain amino acids prior to exercise decreases muscle fatigue and delayed-onset muscle soreness, a syndrome that occurs 24-48 hours after rigorous exercise due to muscle damage. [4] Furthermore, according to a 2008 study from the University of Pavia, Italy, branched-chain amino acid supplementation also regulates the immune system, allowing the proliferation of peripheral blood mononuclear cells as a response to long-distance intense exercise and altering exercise-related cytokine production pattern. [5]

Valine and Liver Disorders

Valine relieves the liver of potentially toxic nitrogen and may help treat liver diseases. Branched-chain amino acids in general are necessary for lymphocyte proliferation and dendritic cell maturation and have been demonstrated to influence gene expression, insulin resistance, and apoptosis and regeneration of liver cells. [6] In a 2010 Japanese study examining the effect of intravenously administered L-valine on liver fibrosis in rat models, L-valine treatment was found to be effective in mitigating liver fibrosis and restoring thrombopoiesis in rats, suggesting the potential of L-valine supplementation as one of the therapeutic managements for patients suffering from liver cirrhosis. In this study, the rats treated with intravenous valine manifested significantly higher blood platelet counts and bone marrow megakaryocyte counts, higher mRNA level of thrombopoietin, and lower mRNA levels of factors associated with liver fibrosis than the control group. [7]

Valine, leucine, and isoleucine have all been reported to inhibit liver cancer cells and induce apoptosis of liver cancer cell lines. Additionally, it appears that branched-chain amino acids also inhibit liver cancer associated with obesity. In patients with advanced chronic liver disorders, these amino acids decline in terms of serum concentration and so the proposed mechanism is that supplying the amino acids restore normal function. [6]