Jian Jie1, Weilin Li1, Guihua Wang1, Xiaoming Xu2. 1. Department of Orthopedics, Pukou Branch Hospital of JiangSu Province Hospital (Nanjing Pukou Central Hospital), 166 Shanghe Street, Jiangpu Street, Pukou District, Nanjing, 211800, Jiangsu, China. 2. Department of Orthopedics, Pukou Branch Hospital of JiangSu Province Hospital (Nanjing Pukou Central Hospital), 166 Shanghe Street, Jiangpu Street, Pukou District, Nanjing, 211800, Jiangsu, China. xuxiaomingmxx@outlook.com.
Abstract
OBJECTIVE: Osteoporosis is affecting the health of postmenopausal women in the world. In case of that, we explored whether FK-506 could ameliorate osteoporosis by inhibiting the activated CaN/NFAT pathway during oxidative stress. METHODS: First, the castrated rat model is constructed through the bilateral ovariectomy. Hologic Discovery (S/N 80347) dual-energy X-ray absorptiometry assessed bone mineral density (BMD) implemented at left femur of rats. Next, hematoxylin-eosin (H&E) staining observed and calculated the changes of bone trabecular, mean trabecular plate separation (Tb.Sp), mean trabecular plate thickness (Tb.Th), and bone volume fraction (BV/TV). Then, CCK-8 assay, TUNEL assay, ALP kit and alizarin red staining detected the viability, apoptosis, alkaline phosphatase (ALP) activity, and capacity of mineralization respectively. At last, commercially available kits detected the levels of ROS and SOD in transfected MC3T3-E1 cells and bone tissues, and Western blot analysis detected proteins related to apoptosis and CaN/NFAT pathway. RESULTS: FK-506 increased the BMD and changes of bone trabecular in female castrated rats. FK-506 inhibited the oxidative stress and apoptosis by suppressing the activated CaN/NFAT pathway. Low dose of FK-506 improved the viability, ALP activity, and mineralization capacity. What's more, it suppressed the apoptosis of H2O2-induced MC3T3-E1 cells, which was deteriorated by the high dose of FK-506. Briefly, low dose of FK-506 inhibited the oxidative stress by suppressing the activated CaN/NFAT pathway, while high dose of that further inhibited the oxidative stress by suppressing the CaN/NFAT pathway. CONCLUSION: FK-506 ameliorates osteoporosis resulted from osteoblastic apoptosis which caused by suppressing the activated CaN/NFAT pathway during oxidative stress.
OBJECTIVE: Osteoporosis is affecting the health of postmenopausal women in the world. In case of that, we explored whether FK-506 could ameliorate osteoporosis by inhibiting the activated CaN/NFAT pathway during oxidative stress. METHODS: First, the castrated rat model is constructed through the bilateral ovariectomy. Hologic Discovery (S/N 80347) dual-energy X-ray absorptiometry assessed bone mineral density (BMD) implemented at left femur of rats. Next, hematoxylin-eosin (H&E) staining observed and calculated the changes of bone trabecular, mean trabecular plate separation (Tb.Sp), mean trabecular plate thickness (Tb.Th), and bone volume fraction (BV/TV). Then, CCK-8 assay, TUNEL assay, ALP kit and alizarin red staining detected the viability, apoptosis, alkaline phosphatase (ALP) activity, and capacity of mineralization respectively. At last, commercially available kits detected the levels of ROS and SOD in transfected MC3T3-E1 cells and bone tissues, and Western blot analysis detected proteins related to apoptosis and CaN/NFAT pathway. RESULTS: FK-506 increased the BMD and changes of bone trabecular in female castrated rats. FK-506 inhibited the oxidative stress and apoptosis by suppressing the activated CaN/NFAT pathway. Low dose of FK-506 improved the viability, ALP activity, and mineralization capacity. What's more, it suppressed the apoptosis of H2O2-induced MC3T3-E1 cells, which was deteriorated by the high dose of FK-506. Briefly, low dose of FK-506 inhibited the oxidative stress by suppressing the activated CaN/NFAT pathway, while high dose of that further inhibited the oxidative stress by suppressing the CaN/NFAT pathway. CONCLUSION: FK-506 ameliorates osteoporosis resulted from osteoblastic apoptosis which caused by suppressing the activated CaN/NFAT pathway during oxidative stress.