Effects and Mechanisms of Action of Acupuncture on Bone and Lipid Metabolism in a Rat Model of Postmenopausal Osteoporosis.

This study investigated the effects of acupuncture on bone and lipid metabolism in a rat model of postmenopausal osteoporosis (PMOP). Thirty-two female Sprague-Dawley rats were randomly assigned to four groups: blank control, sham-operated, model (ovariectomy), and acupuncture treatment (ovariectomy plus acupuncture). Following treatment, bone mineral density (BMD), bone tissue morphological changes with quantitative histomorphometry, serum bone metabolism markers, estradiol (E2) levels at multiple time points, body mass index (BMI), blood lipid indicators, inflammatory factors, and gut microbiota composition were measured in each group. Acupuncture increased femoral BMD after adjusting for femoral shaft thickness (P<0.05) and improved trabecular bone structure, with significant rises in trabecular number, thickness, and bone volume fraction (P<0.05). Serum osteoprotegerin levels increased and osteoclast markers decreased. Serial E2 measurements showed progressive restoration from week 4. Acupuncture reduced BMI (P<0.05), with BMI changes negatively correlating with BMD improvements (r=-0.68, P<0.01). Lipid metabolism and inflammatory markers were significantly improved (P<0.05). Gut microbiota analysis indicated increased abundance of Lactobacillus and Bifidobacterium and decreased pathogenic bacteria (P<0.05). Liquid chromatography-mass spectrometry suggested acupuncture may promote osteogenic differentiation via upregulation of the cAMP-PKA-CREB pathway. Overall, acupuncture effectively enhances bone and lipid metabolism in PMOP rats through hormonal regulation, metabolic modulation, and gut microbiota optimization. Key words Acupuncture " Postmenopausal osteoporosis " Bone metabolism " Lipid metabolism " Estradiol " Gut microbiota " cAMP-PKA-CREB pathway.