Effect Of Thymopentin On Myasthenia Gravis

OBJECTIVE:Although several therapeutic programs are currently available for the treatment of myasthenia gravis(MG),most of them accompany with severe side effects or shortcomings. For the purpose of finding a better pharmaceutical treatment, an immuno-regulator thymopentin targeting to the origin of the disease is tested on the experimental autoimmune myasthenia gravis(EAMG) in this study. The membrane fluidity, Ca2+-ATPase, Na+,K+-ATPase and Superoxide dismutase (SOD) of skeletal muscle cells in EAMG were studied at the same time. METHOD: Fragment of targeting peptides of nicotinic acetylcholine receptors (nAChR) were used to immunize C57BL/6 mice, then the number of nAChR in serum and on membrane of skeletal muscle cells were detected by double diffusion methods and by SDS-PAGE/gel imaging acquisition, respectively, to confirm the establishment of EAMG. Then the EAMG mice were divided into tow groups: the treatment group were injected with thymopentin, the untreated EAMG group were not. Together with normal healthy group, a total of 3 groups of mice were tested for their CD4+/CD8+ ratio, and membrane fluidity,Na+,K+-ATPase,Ca2+-ATPase and SOD in skeletal muscle cells. RESULTs:The success rate of producing EAMG by fragment of nAChR is 67% in this study. The amount of nAchR in EAMG group was significantly less than that of normal group (P<0.05). The differences in the nAChR were also significant between the treatment and EAMG groups, the treatment and normal groups, the EAMG and normal groups with p<0.05,0.001 and 0.001, respectively. No significant difference were found among groups for membrane fluidity,Na+,K+-ATPase,and SOD. However, the Ca2+-ATPase in EAMG group was found to be significantly higher than that of normal group (P < 0.05). CONCLUSION :Thymopentin was found to have a good therapeutic efficacy in diminishing the clinical symptoms of MG. Treatment with thymopentin could normalize the nAChR and CD4+/CD8+ ratio which were significantly reduced in EAMG. The Ca2+-ATPase on skeletal muscle cells in EAMG group was also found to be significantly higher than that of normal group. Although the process of MG was found to have no significant effect on the membrane fluidity, and the activities of Na+,K+-ATPase or SOD of skeletal muscle cells in this study.