Activation of aldehyde dehydrogenase 2 protects ethanol-induced osteonecrosis of the femoral head in rat model.

Objectives: Osteonecrosis of the femoral head (ONFH) is a devastating disease characterized by destructive bone structures, enlarged adipocyte accumulation and impaired vascularization. The aldehyde dehydrogenase 2 (ALDH 2) is the limiting enzyme for ethanol metabolism with many physiological functions. The aim was investigated the potential protective role of activated ALDH 2 by Alda-1 for ethanol-induced ONFH.

Materials And Methods: The ethanol-induced ONFH in rat was performed to explore the protective of Alda-1 by various experimental methods. Subsequently, the effect of Alda-1 and ethanol on the osteogenic and adipogenic differentiation was investigated via multiple cellular and molecular methods. Finally, the effect of Alda-1 and ethanol on the neo-vascularization was detected in Human umbilical vein endothelial cells (HUVECs) and ONFH model.

Results: Firstly, radiographical and pathological measurements indicated that alda-1 protected ethanol-induced ONFH. Moreover, ethanol significantly inhibited the proliferation and osteogenic differentiation of BMSCs, whereas Alda-1 could distinctly rescue it by PI3K/AKT signalling. Secondly, ethanol remarkably promoted the lipid vacuoles formation of BMSCs, while Alda-1 significantly retarded it on BMSCs by AMPK signalling pathway. Finally, ethanol significantly inhibited proliferation and growth factor level resulting in reduced angiogenesis, whereas Alda-1 could rescue the effect of ethanol. Additionally, Alda-1 significantly reduced the occurrence of ONFH and promoted vessel number and distribution in alcoholic ONFH.

Conclusions: Alda-1 activation of ALDH 2 was highly demonstrated to protect ethanol-induced ONFH by triggering new bone formation, reducing adipogenesis and stimulating vascularization.