CCL2 and osteoporosis: A correlation analysis revealed that the expression levels of CCL2, Nos3, and Tgfb3 were significantly positively correlated with multiple parameters of bone microstructure, suggesting that these three genes are involved in the occurrence of osteoporosis in OVX rats, and they are the sensitive genes for evaluating the effect of treadmill exercise in improving bone quality in ovariectomized rats.