RESUMO
To clarify the role of B-12 in the immunological function, serum C3, IgM, IgG, IgE contents, splenocytes expression of CD4, CD8, and CD4 positive intracellular IFN-gamma and IL-4 were examined in B-12-deficient mice, and the effect of the administration of CH3-B-12 was also studied. Serum C3, IgM and IgG contents were lower in B-12-deficient mice than in the control mice. On the other hand, serum IgE content was significantly higher in B-12-deficient mice, and the value in CH3-B-12 administered mice, administered CH3-B-12 to B-12-deficient mice for 48 h before the end of feeding period, showed a tendency to recovery. CD4+CD8- cells and CD4+CD8-/CD4-CD8+ ratio in splenocytes were significantly higher in B-12-deficient mice than in control mice. CD4+IFN-gamma+ cells was significantly lower in B-12-deficient mice than in control mice, and CD4+IL-4+ was significantly higher in B-12-deficient mice than in control mice. These results suggest that B-12-deficiency causes CD4+CD8-T cells shift from the T helper type 1 to the T helper type 2, which participate in the IgE production and elevates CD4+CD8-/CD4-CD8+ ratio. Thus, B-12 plays a role in maintaining the immune function in mice.
Assuntos
Citocinas/sangue , Imunoglobulinas/sangue , Deficiência de Vitamina B 12/imunologia , Vitamina B 12/uso terapêutico , Animais , Relação CD4-CD8 , Complemento C3/metabolismo , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Interferon gama , Interleucina-4 , Masculino , Camundongos , Camundongos Endogâmicos BALB C/imunologia , Vitamina B 12/administração & dosagem , Deficiência de Vitamina B 12/sangue , Deficiência de Vitamina B 12/terapiaRESUMO
Cyanocobalamin, deoxyadenosylcobalamin and methylcobalamin were separately administered to mice sensitized with the ovalbumin antigen to investigate the allergic response. The serum IgE and pulmonary histamine concentrations were significantly lower in all cobalamin (Cbl)-administered groups. The production of interleukin (IL)-2 and IL-4 in splenocytes was also lower in all Cbl-administered groups. These results show that Cbls were effective in mitigating allergic reactions and IL-2 production. CD3+ CD28+ (CD28 is an accessory molecule related to IL-2 production) and CD4+ CD28+ in splenocytes were higher in all the Cbl-administered groups. However, CD3+ CD28-, CD4+ CD28- and CD5+ CD25- (CD25: IL-2 R alpha/p55) were lower in the Cbl-administered groups. In addition, Cbl specifically inhibited the cellular phosphorylation of tyrosine induced by ovalbumin sensitization. These results indicate that the signal in a cell by CD 28 was restrained by Cbl. We infer that Cbl administration significantly reduced the IL-2 concentration, and secondarily the IL-4, IgE and histamine concentrations.
Assuntos
Hipersensibilidade/tratamento farmacológico , Vitamina B 12/uso terapêutico , Animais , Antígenos CD/análise , Complemento C3/metabolismo , Histamina/metabolismo , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Interleucina-2/biossíntese , Fígado/efeitos dos fármacos , Fígado/imunologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fosfotirosina/metabolismo , Baço/efeitos dos fármacos , Baço/imunologia , Baço/metabolismo , Vitamina B 12/metabolismo , Vitamina B 12/farmacologiaRESUMO
To clarify the role of vitamin B12 in the function of cell-mediated and humoral immune functions, the splenocytes expression of CD4, CD8 and serum C3, IgM, IgG concentrations were examined in vitamin B12-deficient rats, and the effect of the administration of methylcobalamin was also studied. The CD4+CD8-/CD4-CD8+ ratio in splenocytes was significantly higher in vitamin B12-deficient rats than in control rats (p < 0.05). The value in the 48 hours after methylcobalamin administration group, was within the normal range (p < 0.05). From these results, the elevation of the CD4+CD8-/CD4-CD8+ ratio by vitamin B12-deficiency was confirmed in rats. The serum C3, IgM and IgG concentrations were lower in the vitamin B12-deficient group than in the control group. These findings suggest that vitamin B12 plays a role in maintaining the immune function in rats.
Assuntos
Relação CD4-CD8 , Complemento C3/metabolismo , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Deficiência de Vitamina B 12/imunologia , Animais , Formação de Anticorpos , Masculino , Ratos , Ratos Wistar/imunologia , Vitamina B 12/administração & dosagem , Vitamina B 12/análogos & derivados , Vitamina B 12/uso terapêutico , Deficiência de Vitamina B 12/sangue , Deficiência de Vitamina B 12/terapiaRESUMO
As a clue to clarifying the role of vitamin B12 (B12) in the function of the complement system, serum C3 content was determined in B12-deficient rats, and the effect of the administration of methylcobalamin (CH3-B12) on the serum C3 content was also studied. It was found that the serum C3 content in rats fed on a vitamin B12-deficient diet for 90 and 120 days significantly decreased compared with that in control rats. The administration of CH3-B12) restored the serum C3 content to control levels. The above results indicate that B12-deficiency depressed the serum C3 content and lowered humoral immunocompetence, and that these changes were ascribable to B12-deficiency.
