Explore on Protective Effect of Guilu Erxian Jiao on Osteoporosis in Ovariectomized Rats Based on TGF-β/Smad and MAPK/NF-κB Signaling Pathway

OBJECTIVE To evaluate the protective effect of Guilu Erxian Jiao on osteoporosis in ovariectomized rats and to explore its mechanism. METHODS A total of 120 rats were randomly divided into normal group, model group, low-dose, medium-dose and high-dose of Guilu Erxian Jiao group and alfacalcidol group. There were 6 groups in total, and all of them were emasculated and modeled except the normal group. Guilu Erxian Jiao was administrated with low, medium, high dose(0.5, 1.5, 2.5 g·kg^-1·d^-1), alfacalcidol was administrated with 0.1 μg·kg^-1·d^-1 dose, the normal group and the model group were given the same amount of normal saline respectively. The pathological changes of femur in rats were detected by HE staining, and the calcium(Ca), phosphorus(P), hydroxyproline(Hyp), alkaline phosphatase(ALP) and tartrate-resistant acid phosphatase(TRAP) of femur were detected by kits. At the same time, Western blotting was used to detect the expression of TGF-β, p-Smad-3 protein and p-JNK, p-ERK, p-P38, p-NF-κB P65 protein in femur of ovariectomized rats. RESULTS Compared with the normal group, the levels of Ca, P, Hyp and ALP in femur of rats in the model group were significantly decreased(P<0.01), while the level of TRAP was significantly increased(P<0.01). The trabecular structure of rats in the model group was disordered, the morphology was thinned and showed signs of fracture. The protein expression levels of TGF-β and p-Smad-3 in femur of the model group were down-regulated, while the protein expression levels of p-JNK, p-ERK, p-P38 and p-NF-κBP65 in femur were up-regulated(P<0.01). Compared with the model group, Guilu Erxian Jiao significantly increased the levels of Ca, P, Hyp and ALP in femur of rats(P<0.01), decreased the level of TRAP in femur of rats(P<0.01), and improved the pathological changes of femur. Meanwhile, Guilu Erxian Jiao significantly induced the expression of TGF-β and p-Smad-3 protein, and significantly decreased the expression of p-JNK, p-ERK, p-P38 and p-NF-κBP65 protein(P<0.01). CONCLUSION Guilu Erxian Jiao can significantly improve osteoporosis in ovariectomized rats, and the mechanism is related to the activation of TGF-β/Smad signaling pathway and the inhibition of MAPK/NF-κB signaling pathway.