Study Of Esculentoside A On Autoimmunity In Mice And Its Molecular Mechanisms

Esculcntoside A (EsA) is the major saponin isolated from the Chinese herb Phytolacca esculenta. It has been showed that EsA possessed comprehensive pharmacological effects in the studys during the last twenty years. It is supposed that EsA might have favorable effect in the treatment of autoimmunity diseases. The possible mechanisms were investigated through anti-inflammation and immunoregulation after the positive results being found. The effect of EsA on gene expression profile changes in murine thymocyte was also investigated using cDNA microarray so that molecular pharmacological mechanism would be clarified fully in three stratifications including animal model, cell and gene expression.The model of autoimmunity was established through immunizing mice with formaldehyde treated campylobacter jejuni strain CJ-S131 and Freund's complete adjuvant. The present study showed that EsA could lower the high level of anti-ds DNA antibody and inhibit the hyperactivity of T and B cells in a dose-dependent manner. In model mice, the proliferation of splcnocyte cells was distinct from that in normal mice whether stimulated with ConA, LPS or without mitogen. Without the existence of mitogen, the inhibitory rate of EsA at the dose of 5, 10, and 20 mg/kg was 26%, 33%, and 42%, respectively (/><0.01). When splenocytes were stimulated with ConA, cell proliferation was close to the normal level at the dose of EsA 10 mg/kg. However, cell proliferation was close to the normal at the dose of EsA 20 mg/kg with LPS as mitogen. The anti-ds DNA antibody increased markedly in the serum of model mice (P<0.01). EsA effectively down-regulated the level of anti-ds DNA antibody in the serum of model mice in a dose-dependent manner. At the dose of EsA 20 mg/kg, the level of ahti-ds DNA antibody was close to the normal.EsA could ameliorate the inflammation in liver and kidney of model mouse through analysis of pathologic section of bowel and could improve the trilogy of rheumatoid arthritis (proliferation of synovium, inflammation, and destruction of cartilage) through analysis of pathologic section of joint. Moreover, foot swell in model mouse had been allievated. Those results suggested that EsA possessed favorable effect on the autoimmunity in mice. In the model mouse, swelled and degenerated hcpatocytes and massive lymphocytes infiltrated in multi-focal sites were clearly observed. After treatment with EsA, the degeneration of hcpatocytes wasimproved, focal necrosis had been absorbed and scatter inflammatory cell infiltration decreased. In the model mouse, the volume of glomerulus and inflammatory cell in glomcrulus increased significantly, hyperemia and bleed in mcscnchymal and massive inflammatory cell infiltration could be observed. Treated with EsA, lymphocyte infiltration markedly decreased. The higher the dose of EsA was, the smaller the volume of glomerulus was and the more remittent the inflammation of glomerulus became. Synovium hyperplasia and synovial pannus were observed in the ankle joint of model mouse. Moreover, the new blood vessel under the synovium increased and its permeability was augmented. Synovium was heavily infiltrated with focal inflammatory cells and cartilage adjacent to synovial pannus was invaded and degraded. The higher the dose of EsA was, the more remittent the inflammation of ankle joint became. Synovial pannus decreased and cartilage could be observed. When the dose of EsA was 20 mg/kg, the formation of synovial pannus was inhibited significantly and the intact cartilage could be observed.Compared with normal mouse, more severe swell was observed in the hindlimb of model mouse. The swell degree in left-side soles was more severe than in right-side soles. During the experiment, the swell of hindlimb in model mouse had been improved owing to the treatment of EsA. The weight of model mouse had no striking difference with that of normal mouse and showed no obvious change with the treatment of EsA.To investigate the possible pharmacological machnism of EsA on autoimmunity disease, two parts o...