| Objective To study the effect of cornuside I on the proliferation and osteogenic differentiation of rat primary osteoblasts based on Wnt signaling pathway and endoplasmic reticulum stress pathway. Methods Primary rat osteoblasts were extracted. Effects of cornuside I on osteoblast proliferation and differentiation under different concentrations and different intervention days were examined with CKK8and alkaline phosphatase staining. Real-time PCR was used to detect the mRNA expression of Wnt2, β-catenin, BMP2, OPG, NOX4, and PERK. The protein expression of Wnt2, β-catenin, PDI, CHOP, and BIP was detected by Western blotting. Results CKK8 assay and ALP staining showed that cornuside I had certain effect on the proliferation and differentiation of osteoblasts. Under the different concentrations of cornuside I, osteoblasts showed different degrees of proliferation. Compared with the blank control group, the mRNA expression levels of Wnt2, BMP2, β-catenin, OPG, and NOX4 increased significantly (P<0.01), while the mRNA expression of PERK decreased significantly (P<0.01). Compared with the blank control group, the expressions of Wnt2, β-catenin, and PDI protein in the osteoblasts of the cornuside I group increased significantly (P<0.01), the expression of CHOP increased slightly (P>0.05). The protein expression level of BIP decreased significantly (P<0.01). Conclusion Cornuside I at 1 mmol/mL concentration is the best in promoting the proliferation and differentiation of osteoblasts. It significantly increases the mRNA expression levels of Wnt2, BMP2, β-catenin, OPG, and NOX4 in osteoblasts, but decreases he mRNA expression level of PERK. The protein expressions of Wnt2, β-catenin, and PDI are increased, but the expression of BIP is decreased. Under the intervention of cornuside I, Wnt signaling pathway and endoplasmic reticulum stress pathway play an important regulatory role in osteogenesis. |