Objective To study the effect of TGF-β1/Smad4 signaling pathway on ovariectomized osteoporosis rats, and to analyze the intervention mechanism of acupuncture therapy on bone marrow microenvironment in rats. Methods A total of 60 SPF female Wistar rats were randomly divided into blank group (Group A), model group (Group B), acupuncture group (Group C) and estradiol group (Group D), with 15 rats in each group. Except Group A, other rats were ovariectomized to establish osteoporosis animal models. After the recipe was successfully modeled, Group C was alternately given electroacupuncture stimulation of "Shenshu" "Sanyinjiao""Guanyuan"and"Zusanli", 15 minutes each time, once a day. Group D was treated with estradiol valerate according to the equivalent dose of human and mice for 12 weeks. The changes of bone metabolism related markers in serum, bone mineral density and trabecular microstructure of distal femur were compared and analyzed; the expression levels of Runx2, PPAR γ, TGF-β1, Smad4 protein and mRNA in bone tissue of distal femur were compared. Results After modeling, compared with the blank group, the bone mineral density of rats in each group was significantly decreased (P<0.05), and the serum levels of bone metabolism markers CBF-α1, BALP, PINP, OC, CTX-I were significantly increased (P<0.05); the relative bone volume fraction (BV/TV),bone trabecular separation(Tb.Sp), trabecular thickness(Tb.Th),the number of trabeculae (TB.N), connection density (Conn.d) and structural model index (SMI) were significantly increased (P<0.05); the expression of Runx 2, PPARγ, TGF-β1, Smad 4 protein and mRNA in distal femur decreased (P<0.05). After 12 weeks of intervention, compared with the model group, the microstructure of trabecular bone in the estradiol group and the acupuncture group was significantly improved, and the expressions of Runx 2, PPARγ, TGF-β1, Smad 4 protein and mRNA in the bone tissue of distal femur were increased (P<0.05), and the acupuncture group was significantly better than the estradiol group (P<0.01). Conclusion Acupuncture at "Shenshu""Sanyinjiao""Guanyuan"and"Zusanli" can improve bone marrow microenvironment, improve bone trabecular microstructure and increase bone mass in ovariectomized rats. The mechanism may be related to the regulation of TGF-β1/Smad 4 signaling pathway by acupuncture. |