二甲双胍联合柚皮苷调控氧化应激与成骨分化改善绝经后骨质疏松症OA

BACKGROUND:Postmenopausal osteoporosis is a systemic metabolic bone disease caused by estrogen deficiency.Its occurrence can be attributed to oxidative stress and bone metabolic disorders resulting from estrogen deficiency.Previous studies have shown that metformin and naringin possess metabolic regulatory and osteogenic activities,but the combined effect of the two remains unclear. OBJECTIVE:To investigate the therapeutic efficacy and potential mechanism of metformin combined with naringin in postmenopausal osteoporosis. METHODS:Female Sprague-Dawley rats were randomly divided into sham-operated group,model group,metformin group,naringin group,combination group,and raloxifene group.A bilateral ovariectomized rat model was established.After 12 weeks of treatment,bone microarchitecture and bone remodeling status were evaluated using micro-CT,hematoxylin-eosin staining,and immunohistochemistry.Serum bone turnover marker levels were measured by ELISA.In vitro experiments using MC3T3-E1 and RAW264.7 cell lines were set up with a control group,metformin group,naringin group,and metformin+naringin group.Cell counting kit-8 assay was used to evaluate cell proliferation;alkaline phosphatase staining and alizarin red staining were used to assess osteogenic differentiation and mineralization;tartrate-resistant acid phosphatase staining was used to assess osteoclast differentiation;a reactive oxygen species fluorescent probe was used to detect intracellular reactive oxygen species levels in RAW264.7 cells;immunofluorescence was used to detect adenosine monophosphate-activated protein kinase(AMPK)activation,β-catenin enhancement,and nuclear translocation;western blot and qRT-PCR were used to detect the expression of key molecules in the AMPK-β-catenin signaling axis and the nuclear factor-κB pathway,as well as the expression of osteogenic and osteoclast-related proteins. RESULTS AND CONCLUSION:(1)In vivo,combined metformin and naringin treatment significantly improved bone mineral density in ovariectomized rats and have better efficacy than either monotherapy in increasing bone volume fraction and preserving trabecular microarchitecture,with effects comparable to those of raloxifene.The combination also mitigated the high-turnover bone state induced by ovariectomy,as reflected by increased procollagen type Ⅰ N-terminal propeptide and reduced C-terminal telopeptide of type Ⅰ collagen and tartrate-resistant acid phosphatase levels,without evidence of overt hepatorenal toxicity.(2)In vitro,the combination displayed a clear synergistic effect by enhancing osteoblast proliferation and mineralization while suppressing osteoclast differentiation and reactive oxygen species level.Western blot and qRT-PCR further confirmed the activation of the AMPK and Wnt/β-catenin pathways,with upregulation of phosphorylated AMPK,β-catenin,and osteocalcin,together with inhibition of nuclear factor-κB-dependent osteoclastogenic signaling.These findings suggest that metformin combined with naringin alleviates postmenopausal osteoporosis,by coordinately activating the AMPK-β-catenin axis,improving the oxidative stress milieu,and restoring the balance between bone formation and bone resorption.