Restitution of epithelial cells during intestinal mucosal wound healing: the effect of a polysaccharide from the sclerotium of Lignosus rhinocerotis (Cooke) Ryvarden

Abstract Ethnopharmacological relevance Lignosus rhinocerotis (Cooke) Ryvarden cultivar TM02, also known as tiger’s milk mushroom, is regarded as important folk medicine in Malaysia, while is used for the treatment of liver cancer, chronic hepatitis, gastric ulcer in traditional Chinese medicine. However, there is no compilation of scientific evidence that its protection for gastric, and no attempts have been made to understand how polysaccharides in Lignosus rhinocerotis might promote intestinal mucosal wound healing. Aim of the study: This study aimed to investigate the effect and mechanism of β-glucan prepared from L. rhinocerotis using an enzymatic method on epithelial restitution during intestinal mucosal damage. Materials and methods Based on FT-IR, MALDI-TOF-MS, HPSEC-MALLS-RID, and AFM, the structure of polysaccharides from L. rhinocerotis was analysed. In addition, polysaccharides were used to test for wound healing activity in IEC-6 cells by measuring cell migration, proliferation, and expression of cell division control protein 42, Rac-1, RhoA, and Par-3. Results β-glucan was extracted using enzyme-assisted extraction, and a yield of approximately 8.5 ± 0.8% was obtained from the dried biomass. The β-glucan extracted by enzyme-assisted extraction (EAE) of polysaccharides was composed entirely of D-glucose with a total carbohydrate content of 95.5 ± 3.2%. The results of HPLC, FTIR, and MALDI-TOF-MS analyses revealed EAEP to be confirmed as β-glucan. The molecular weight of prepared β-glucan was found to be 5.315 × 104 g/mol by HPSEC-MALLS-RID. Furthermore, mucosal wound healing studies showed that the treatment of IEC-6 with a β-glucan concentration of 200 μg/mL promoted cell migration and proliferation, and it enhanced the protein expression of cell division control protein 42, Rac-1, RhoA, and Par-3. Conclusions The present study reveals that the prepared β-glucan accelerates intestinal epithelial cell proliferation and migration via activation of Rho-dependent pathway. Hence, β-glucan can be employed as a prospective therapeutic agent for the treatment of diseases associated with gastrointestinal mucosal damage, such as peptic ulcers and inflammatory bowel disease.