Metabolomic signature of amino acids in plasma of patients with non-segmental Vitiligo

Introduction Vitiligo pathogenesis is complicated, and several possibilities were suggested. However, it is well-known that the metabolism of pigments plays a significant role in the pathogenicity of the disease. Objectives We explored the role of amino acids in vitiligo using targeted metabolomics. Methods The amino acid profile was studied in plasma using liquid chromatography. First, 22 amino acids were derivatized and precisely determined. Next, the concentrations of the amino acids and the molar ratios were calculated in 31 patients and 34 healthy individuals. Results The differential concentrations of amino acids were analyzed and eight amino acids, i.e., cysteine, arginine, lysine, ornithine, proline, glutamic acid, histidine, and glycine were observed differentially. The ratios of cysteine, glutamic acid, and proline increased significantly in Vitiligo patients, whereas arginine, lysine, ornithine, glycine, and histidine decreased significantly compared to healthy individuals. Considering the percentage of skin area, we also showed that glutamic acid significantly has a higher amount in patients with less than 25% involvement compared to others. Finally, cysteine and lysine are considered promising candidates for diagnosing and developing the disorder with high accuracy (0.96). Conclusion The findings are consistent with the previously illustrated mechanism of Vitiligo, such as production deficiency in melanin and an increase in immune activity and oxidative stress. Furthermore, new evidence was provided by using amino acids profile toward the pathogenicity of the disorder.

Automated summary

This study explored the role of amino acids in vitiligo using targeted metabolomics. The results showed significant differences in the concentrations and ratios of certain amino acids in vitiligo patients compared to healthy individuals, with cysteine, glutamic acid, and proline concentrations increasing significantly, while arginine, lysine, ornithine, glycine, and histidine concentrations decreasing significantly.