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Published on: September 7, 2013
Melatonin treatment prevents modulation of cell-mediated immune response induced by propoxur in rats
Sanvidhan G Suke1, Rahul Pathak, Rafat S Ahmed
1Environmental Biochemistry and Immunology Laboratory, Department of Biochemistry, University College of Medical Sciences and G.T.B. Hospital (University of Delhi), Dilshad Garden, Delhi 110 095, India.
Abstract:
The effect of melatonin, a major secretory product of the pineal gland, in attenuation of propoxur (2-isopropoxy phenyl N-methyl carbamate)-induced modulation of cell-mediated immune (CMI) response was studied in rats. Male Wistar albino rats were exposed to propoxur (a widely used pesticide) orally (10 mg/kg) and/or melatonin (10 mg/kg) orally for 4 weeks. CMI was measured by delayed-type hypersensitivity (DTH), leucocyte and macrophage migration inhibition (LMI and MMI) responses and estimation of cytokines TNF-alpha and IFN-gamma levels. Rats exposed to propoxur for 4 weeks showed significant decrease in DTH, LMI and MMI responses. Propoxur also suppressed TNF-alpha and IFN-gamma production significantly. Administration of melatonin alone caused a significant increase in DTH response. Although there were no changes in the LMI and MMI response, the cytokine levels were significantly increased, as compared to control. Co-administration of melatonin along with propoxur significantly nullified the effect of the pesticide on the CMI response, except DTH and reversed levels of cytokines to near control/normal values. Thus, melatonin treatment considerably attenuated immunomodulation caused by sub-chronic treatment of propoxur in experimental animals.
Insights
Melatonin supplementation can protect against pesticide-induced immune suppression. This study shows melatonin attenuated the negative effects of propoxur (a pesticide) on the cell-mediated immune (CMI) response in rats.
Area of Science:
- Immunology
- Toxicology
- Endocrinology
Background:
- Pesticides like propoxur can negatively impact the immune system.
- Melatonin, a hormone from the pineal gland, is known for its antioxidant and immune-modulating properties.
Purpose of the Study:
- To investigate the protective effects of melatonin against propoxur-induced immunomodulation in rats.
- To assess the impact of propoxur and melatonin on cell-mediated immunity (CMI) parameters.
Main Methods:
- Male Wistar albino rats were treated orally with propoxur (10 mg/kg) and/or melatonin (10 mg/kg) for 4 weeks.
- Cell-mediated immune response was evaluated using delayed-type hypersensitivity (DTH), leucocyte migration inhibition (LMI), and macrophage migration inhibition (MMI) tests.
- Levels of pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma), were measured.
Main Results:
- Propoxur exposure significantly decreased DTH, LMI, MMI responses, and suppressed TNF-alpha and IFN-gamma levels.
- Melatonin alone increased DTH response and cytokine levels, without affecting LMI or MMI.
- Co-administration of melatonin with propoxur significantly counteracted the pesticide's immunosuppressive effects, restoring cytokine levels near normal.
Conclusions:
- Melatonin treatment significantly attenuated the immunomodulatory effects of sub-chronic propoxur exposure in rats.
- Melatonin shows potential as a protective agent against pesticide-induced immune system damage.
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