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.
MATERIALS AND METHODS: The composition of L. rhinocerotis TM02 cultivar was analyzed. Organ bath experiment was employed to study the bronchodilator effect of Lignosus rhinocerotis cold water extract (CWE) on rat isolated airways. Trachea and bronchus were removed from male Sprague-Dawley rats, cut into rings of 2 mm, pre-contracted with carbachol before adding CWE into the bath in increasing concentrations. To investigate the influence of incubation time, tissues were exposed to intervals of 5, 15 and 30 min between CWE concentrations after pre-contraction with carbachol in subsequent protocol. Next, tissues were pre-incubated with CWE before the addition of different contractile agents, carbachol and 5-hydroxytrptamine (5-HT). The bronchodilator effect of CWE was compared with salmeterol and ipratropium. In order to uncover the mechanism of action of CWE, the role of beta-adrenoceptor, potassium and calcium channels was investigated.
RESULTS: Composition analysis of TM02 cultivar revealed the presence of β-glucans and derivatives of adenosine. The extract fully relaxed the trachea at 3.75 mg/ml (p