Publications by authors named "Muthammal Sudarshan"
Although hexavalent chromium Cr [VI] is known as a toxicant in the aquatic environment, its effect in low, environmentally relevant concentration (ERC; 2 mg L) is less characterized. Against this backdrop, the effects of Cr [VI] in ERC on zebrafish liver has been investigated in this study. Fluorescence microscopy and gel electrophoresis detected excess DNA damage and cell death via apoptosis in 2 mg L Cr [VI]-treated fish when compared with that of control.
View Article and Find Full Text PDFArsenic and fluoride are two naturally occurring toxicants to which various organisms including a major part of the human populations are co-exposed to. However, interactions between them inside body are quite complicated and needs proper evaluation. Inconclusive reports regarding their combined effects on brain prompted us to conduct this study where we investigated their individual as well as combined effects on female zebrafish brain at environmentally relevant concentrations (50 μgL arsenic trioxide and 15 mgL sodium fluoride) after different time intervals (15, 30 and 60 days).
View Article and Find Full Text PDFFluoride (F) is an essential trace element, but chronic exposure beyond the permissible limit (1.5 ppm) effectuates dental and skeletal fluorosis. Although 200 million people across the world are suffering from toxic manifestations of F, till now proper treatment is not available.
View Article and Find Full Text PDFArticle Synopsis
- Chronic fluoride exposure (above 1.5 ppm) leads to health issues by causing oxidative stress and damaging DNA beyond repair.
- In a study, Swiss albino mice exposed to 15 ppm fluoride for 8 months showed damage in various organs, along with increased oxidative stress indicators like GSH depletion and lipid peroxidation.
- The research found that fluoride exposure altered the expression of key DNA repair genes Ogg1 and Rad51, with hypermethylation affecting Rad51, potentially linking fluoride-induced neurotoxicity to epigenetic changes.
Mixture effect of arsenic and fluoride at environmentally relevant concentrations in zebrafish (Danio rerio) liver: Expression pattern of Nrf2 and related xenobiotic metabolizing enzymes.
Aquat Toxicol
August 2019
Article Synopsis
- Nrf2 is a key transcription factor that helps regulate protective enzymes and cellular balance against oxidative stress.
- Both arsenic and fluoride can trigger Nrf2 activation and often coexist in the environment, leading to complex effects on organisms exposed to them.
- The study found that combined exposure to these toxicants in zebrafish resulted in signs of oxidative stress, elevated Nrf2 activity, and altered expression of stress response genes, revealing important insights into how these substances affect liver function.
Arsenic is a Group I human carcinogen, and chronic arsenic exposure through drinking water is a major threat to human population. Liver is one of the major organs for the detoxification of arsenic. The present study was carried out in mice in vivo after arsenic treatment through drinking water at different doses and time of exposure.
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