Immunotherapeutic effects of pentoxifylline in type 1 diabetic mice and its role in the response of T-helper lymphocytes

OBJECTIVES Pentoxifylline is an immunomodulatory and anti-inflammatory agent and is used in vascular disorders. It has been shown that pentoxifylline inhibits proinflammatory cytokines production. The purpose of this study was to investigate the therapeutic effects of pentoxifylline on the treatment of autoimmune diabetes in mice. MATERIALS AND METHODS Diabetes was induced by multiple low dose of streptozotocin (MLDS) injection (40 mg/kg/day for 5 consecutive days) in male C57BL/6 mice. After induction of diabetes, mice were treated with pentoxifylline (100 mg/kg/day IP) for 21 days. Blood glucose levels and plasma levels of insulin were measured. Splenocytes were tested for proliferation by MTT test and cytokine production by ELISA. RESULTS Pentoxifylline treatment prevented hyperglycemia and increased plasma insulin levels in the diabetic mice. Aside from reducing lymphocyte proliferation, pentoxifylline significantly inhibited the production of proinflammatory interleukin 17 (IL-17) as well as interferon gamma (IFN-γ), while increased anti-inflammatory cytokine IL-10 as compared with those in MLDS group (diabetic control group). CONCLUSION These findings indicate that pentoxifylline may have therapeutic effect against the autoimmune destruction of the pancreatic beta-cells during the development of MLDS-induced type 1 diabetes in mice.