Expression Analysis of Vitamin D Metabolism-Related Genes in Rat Testes

This study examined vitamin D metabolism-related genes in rat testes, revealing that the testes play a significant role in vitamin D metabolism, akin to the liver and kidneys. Notably, while Cyp2r1 mRNA expression was lower in the testes compared to the liver and kidneys, protein expression was higher in the testes. Vdbp protein was present in serum but low in tissue samples, indicating its role as a secretory protein. The research also highlighted the potential involvement of the colon in vitamin D metabolism and the interplay between vitamin D and testosterone. A related study with 80 male androgenetic alopecia (AGA) patients and 60 controls found lower blood 25(OH)D levels in AGA patients, suggesting vitamin D supplementation could be beneficial. The findings emphasize the testes' role in maintaining blood 25(OH)D levels and the need for further research on vitamin D's impact on male reproductive health and conditions like AGA.