Efeito da piperina sobre células B murinas e no modelo Lúpus Eritematoso Sistêmico (LES) induzido por pristane em camundongos BALB/c

Abstract

The B lymphocytes are involved in humoral immune response. They have the capacity to differentiate into plasma cells producing of antibodies with high specificity against pathogens and in memory cells. However, genetic, environmental and hormonal factors may be responsible by dysregulation for the immune system, which becomes unable to prevent or eliminate the body's auto-reactive B cells producing autoantibodies. The pathogenic role of B cells has received considerable attention after establishing treatment of autoimmune diseases. Piperine, the main constituent of the fruit of black pepper (Piper nigrun Linn.) and long pepper (P. longum Linn.) has various physiological effects, including on immune function in normal and transformed cells, giving possibilities in its therapeutic use . The overall goal of our study was to evaluate in vitro the ability of piperine in modulating the response of purified splenic B cells from mice of BALB/c mice, and in vivo, the effect of piperine on the model of autoimmunity, Systemic Lupus Erythematosus (SLE), as well as its effect on the response to thymus-dependent and thymus-independent antigens. The cytotoxic effect of differents concentrations of the piperine was evaluated by XTT method and the concentrations of 15 μM, 3 μM and 1 μM of piperine were selected to the experiments in vitro. We found that 15 μM dose of piperine was able to inhibit proliferation of splenic B cells purified by route BCR and TLR4, the secretion of IgM by route BCR and expression of co-stimulatory molecule CD86 by route TLR4 and BCR. The dose of piperine 3 μM was only able to inhibit the expression of co-stimulatory molecule CD86. In the evaluation of piperine on the model SLE observed that doses of piperine (2.25mg/kg and 4.5mg/kg) did not prevent development of the typical signs of the disease as lipogranulomas formation, joint swelling, immune complex deposition in the glomerulus kidney and splenomegaly. Only the dose 4.5mg/kg of piperine reduced proteinuria of animals at the SLE. In response to thymus-dependent antigens and thymus-independent piperine (2.25mg/kg and 4.5 mg/kg) did not affect the levels of serum IgG at 14th and 21th days and the serum levels of IgM to 7th and 14th days, respectively. Based on these results, we can conclude only that piperine modulates murine B cells in vitro, with no effect on the development of SLE.