GAS5 protects against osteoporosis by targeting UPF1/SMAD7 axis in osteoblast differentiation
ELIFE
Authors: Li, Ming; Xie, Zhongyu; Li, Jinteng; Lin, Jiajie; Zheng, Guan; Liu, Wenjie; Tang, Su'an; Cen, Shuizhong; Ye, Guiwen; Li, Zhaofeng; Yu, Wenhui; Wang, Peng; Wu, Yanfeng; Shen, Huiyong
Abstract
Osteoporosis is a common systemic skeletal disorder resulting in bone fragility and increased fracture risk. It is still necessary to explore its detailed mechanisms and identify novel targets for the treatment of osteoporosis. Previously, we found that a lncRNA named GAS5 in human could negatively regulate the lipoblast/adipocyte differentiation. However, it is still unclear whether GAS5 affects osteoblast differentiation and whether GAS5 is associated with osteoporosis. Our current research found that GAS5 was decreased in the bones and BMSCs, a major origin of osteoblast, of osteoporosis patients. Mechanistically, GAS5 promotes the osteoblast differentiation by interacting with UPF1 to degrade SMAD7 mRNA. Moreover, a decreased bone mass and impaired bone repair ability were observed in Gas5 heterozygous mice, manifesting in osteoporosis. The systemic supplement of Gas5-overexpressing adenoviruses significantly ameliorated bone loss in an osteoporosis mouse model. In conclusion, GAS5 promotes osteoblast differentiation by targeting the UPF1/SMAD7 axis and protects against osteoporosis.
Yu Gan Long reduces rat liver fibrosis by blocking TGF-beta 1/Smad pathway and modulating the immunity
BIOMEDICINE & PHARMACOTHERAPY
Authors: Xia, Yu; Yu, Bo; Ma, Chaozhi; Tu, Yijun; Zhai, Ling; Yang, Yanfang; Liu, Dan; Liu, Yanwen; Wu, Hezhen; Dan, Hanxiong; You, Pengtao
Abstract
Yu Gan Long (YGL) is a Chinese traditional herbal medicine that has been used in the treatment of liver fibrosis for many years in clinical practice. However, its anti-hepatofibrotic mechanism has not been studied yet. In this study, the effect and mechanism of YGL in reducing liver fibrosis was demonstrated in vivo. Our results showed that liver fibrosis biomarkers collagen IV (Col IV), type III precollagen (PCIII), hyaluronuc acid (HA) and laminin (LN), were increased after CCl4 treatment and decreased by YGL. Among the liver fibrosis indicators, alpha-smooth muscle actin (alpha-SMA) was decreased by YGL in the CCl4-treated rats, while MMP2 and MMP9 was upregulated followed by TIMP1 downregulation. Proteins involved in liver fibrosis such as p-Smad2, p-Smad3 and Smad4 were down-regulated, while Smad7 protein was up-regulated by YGL after CCl4-induced liver damage. YGL also suppressed the increase of TGF-beta 1, TNF-alpha, IL-1 beta, IL-6, IL-4 and IL-17 A induced by CCl4 treatment, while promoted IFN-gamma expression. Finally, the transcription factors ROR-gamma t and GATA3 were decreased, while T-bet was increased after YGL treatment. These results suggested that YGL attenuated CCl4-induced hepatic fibrosis by accelerating the extracellular matrix degradation, blocking the TGF-beta 1/Smad signaling pathway and modulating the balance among IL-4, IL-17 A and IFN-gamma, demonstrating YGL protective effect and its potential mechanisms in treating liver fibrosis.