Immune Intervention Of The Chinese Medicine On The Development Of IDDM Murine Model And The Mechanism Study

Objective: To investigate the immune interventional effect and immunoloregulational mechanism of the Chinese medicine-Paecilomyces Hepiali Chen Mycelium (PHC) on the insulin-dependent diabetes mellitus (IDDM) induced by streptozotocin in murine.Methods: The IDDM model was induced by multiple low dose of streptozotocin 40mg/kg for 5 days in Balb/c mice and 50mg/kg once in Wistar rats. Different doses of PHC (75mg/kg, 50mg/kg and 25mg/kg) were given by p.o. injection 7 days before the establishment of IDDM model, respectively, for consecutive 28 days. The positive and negative controls were given metformin 60mg/kg and normal saline, respectively, in the same region. Effects of which were confirmed by checking glucocemia once a week and hydroposia,body weight and urine glucose every day. After 28 days, pancreas were taken out, fixed with formalin and stained with hematoxylin-eosine for histological analysis and immunohistochemistry assaying. The activity of SOD, content of TG, TC, MDA, GSP and IAA in serum and cytokine secretion of IL-2, IL-10 was detected. MTT method was used to evaluate the T cell proliferation by PHC in vitro. ELISA method was used to evaluate the cytokine secretion of IL-2 and IL-10 in supernatants of T cell suspension.Results: The IDDM model induced by streptozotocin lasted for 28 days with the significant characteristic as insulitis. Moreover, it was found that the level of glucosaemia was significantly decreased in both low and middle PHC groups. Less inflammatory cells infiltration and no obviousβcell damage were found in islets and down–regulated of IL-2 and GSP (p<0.05) content were observed in the two groups by comparing with the control group. However, few of the same phenomena was found in high dose of PHC. But they were all found that the significant changes of SOD activity and TG, TC, MDA contents. Immunosuppressive effect involved in T cell proliferation suppression and cytokine down-regulation were also displayed in vitro.Conclusion: Low and middle doses of PHC shown significant hypoglycemic effect in streptozotocin induced IDDM, the anti-diabetic effect of which associated with free radicals clearance, hypolipoid and immunosuppressive effect.