The effect of ascorbic acid on histopathological, biochemical, pharmacological, and immunological toxicity of chronic lead acetate exposure on the spleen in a rat model

Objective To evaluate the effect of vitamin C on histopathological, biochemical, and immunotoxicity of chronic lead exposure in the spleen of a rat model. Methods The rats were divided into five groups of 10 rats each: group I received normal saline orally as a control group; groups II and III received lead acetate for 4 and 8 weeks, respectively; and groups IV and V received lead acetate and vitamin C for 4 and 8 weeks, respectively. The spleen was excised and processed for light, electron microscopic, histopathological, and biochemical analyses. Quantitative assessments of matrix metalloproteinase-2 (MMP-2), MMP-9, interleukin-2 (IL-2), IL-6, and tumor necrosis factor-alpha gene expressions were performed by real-time PCR. Results The examination of control and vitamin C with lead acetate supplemented groups revealed normal splenic architecture. In contrast, the spleen of lead-intoxicated groups exhibited degenerative changes in the spleen, with a significantly decreased expression of IL-2, glutathione peroxidase, superoxide dismutase, and hemoglobin (P<0.05), with significantly increased proinflammatory cytokine (IL-6 and tumor necrosis factor-alpha) expressions, concomitantly with increased oxidative products (malondialdehyde) and protease enzymes (MMP-2 and MMP-9) in the spleen tissues. The coadministration of vitamin C with lead for 4 weeks markedly resolved these changes. Conclusion This study may specify the efficiency of vitamin C in lead toxicity prevention in the spleen, represented by the reduced splenic harmful changes produced by lead administration.