Integrative in-silico and in-vitro analysis of taurine and vitamin B12 in modulating PPARγ and Wnt signaling in hyperhomocysteinemia-induced osteoporosis.

Abstract

Peroxisome proliferator-activated receptor-γ (PPARγ) is a critical regulator of adipogenesis and bone metabolism, playing complex roles in osteoporosis. This study investigates the effects of taurine and homocysteine on PPARγ, focusing on their roles in osteoclastogenesis and bone health. In-silico analyses, including molecular docking and molecular dynamic simulations, revealed that both taurine and homocysteine bind competitively to the PPARγ ligand-binding domain, exhibiting distinctive antagonistic modes, including destabilization of PPARγ's key helices H3, H4/5, H11, and H12. In-vitro experiments further supported these results, demonstrating that taurine protects against oxidative damage, enhances bone mineralization, and reduces the expression levels of PPARγ, while also downregulating negative regulators of the Wnt signaling pathway, such as SOST and DKK1. Homocysteine, on the other hand, was observed to increase the expression of these regulators and impair bone formation. Vitamin B12 was included in the study due to its known role in mitigating hyperhomocysteinemia, a condition linked to impaired bone health and reduced taurine levels. While vitamin B12 alone demonstrated some beneficial effects, it did not achieve the same level of efficacy as taurine. However, a combination of taurine and vitamin B12 showed greater efficacy in ameliorating hyperhomocysteinemia-induced osteoporosis. Overall, this study highlights taurine's therapeutic potential in counteracting the adverse effects of hyperhomocysteinemia on bone health and underscores the need for further research into taurine's mechanisms in osteoporosis treatment.