Estimation of Tyrosinase-Related Protein 1 (TRP-1) Gene Expression in Human Gingiva and Its Correlation With Gingival Melanin Hyperpigmentation: A Pilot Study.

Background Melanin synthesis in humans relies on the activity of the tyrosinase enzyme, along with tyrosinase-related proteins 1 and 2 (TRP-1 and TRP-2). TRP-1 functions as a 5,6-dihydroxyindole-2-carboxylic acid oxidase and plays a crucial role in activating and stabilizing tyrosinase, as well as in melanosome synthesis. However, TRP-1 gene expression in human gingiva has not been explored. Therefore, this study aimed to estimate TRP-1 gene expression in human gingiva. Aim The aim of the study was to estimate TRP-1 gene expression in human gingiva and examine its correlation with the degree of gingival melanin hyperpigmentation. Materials and methods Gingival tissue samples were collected from individuals undergoing gingival depigmentation surgery due to concerns about blackish-looking gums. The gingival epithelial tissue was excised under local anesthesia using a surgical scalpel blade. The excised tissue, including a thin layer of underlying connective tissue, was sent to the laboratory for TRP-1 gene expression analysis using the RT-PCR technique. Results The levels of TRP-1 gene expression in human gingiva ranged from 0.459 to 0.973. TRP-1 gene expression in the gingival tissues showed a correlation with the degree of gingival melanin hyperpigmentation, with lower expression levels observed at sites with mild to moderate pigmentation and higher levels at sites with severe pigmentation. Conclusions TRP-1 gene expression in human gingiva was positively correlated with the degree of gingival melanin hyperpigmentation, suggesting its potential role in the regulation of gingival melanin pigmentation.