Curculigo orchioides polysaccharides extraction, characterization, and their protective effects against femoral head necrosis

The use of steroid drugs such as dexamethasone in long-term treatment poses a challenge called femoral head necrosis. To reduce the destructive effects of dexamethasone, the use of herbal suppressants such as Curculigo orchioides polysaccharides (COPs) is recommended despite the ambiguities in their chemical composition and the effects of each component on the anti-necrosis activity of the femoral head. In this study, after separation of COPs through hot water-ethanol precipitation method and purification through DEAE-Sepharose fast flow column, their properties were explained by FTIR, NMR, methylation and chromatography. Moreover, the COPs biocompatibility and its inhibitory effects against dexamethasone-induced cytotoxicity were evaluated by MTT assay and gene expression on human primary osteoblasts cells. The results exhibit that the 4756 Da molecular weight COPs is generally composed of Rha, Ara, Fru, Xyl, Man, Glc, Gal, Glu A and Gal A. Also, MTT results recognized high biocompatibility of COPs and suppressive effect on dexamethasone. Also, COPs significantly reduced dexamethasone-induced intracellular levels of apoptosis and ROS. Furthermore, the use of COPs has significantly increased ALP activity, collagen content and mineralization, which are very effective in differentiating HPOS cells to repair bone tissue. Meanwhile, the gene expression outcomes indicate an increase in Bcl-2 expres sion gene and decrease in BAX, Caspase-9 and Caspase-3 gene expression in the presence of COPs, which are important in controlling apoptotic activity and bone regeneration. Overall, this study revealed that COPs can lead to the treatment of femoral head necrosis. (c) 2021 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).