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Abstract: It has been established in mammalian system including humans that direct damage to proteins or chemical modification of amino acids in proteins during oxidative stress can give rise to protein carbonyls. Protein carbonyl induction, as a biomarker of oxidative stress was used in laboratory studies to assess the toxic effects of pesticides in freshwater fish, Channa punctata (Bloch), exposed to deltamethrin, endosulfan and paraquat. Protein carbonyls were measured in gills, kidney and liver. Significant (P <0.05–0.001) increase in protein carbonyls was observed in response to single 48h exposure to various pesticides in all the tissues. The time kinetics study involving deltamethrin (0.75μg/L) also showed a significant (P <0.05–0.001) induction of protein carbonyls in all the organs. The induction was significant (P <0.05–0.001) in all the durations of exposure (12h, 96h, 7 days, 14 days, 28 days). However, relatively pronounced induction was observed during shorter duration of exposure. The findings of the present investigation showed that deltamethrin had the maximum oxidative stress-inducing potential among the three pesticides used and gills are the most sensitive organs prone to oxidative damage. It is suggested that measurement of carbonyl groups may provide a convenient technique for detecting and quantifying oxidative modification of proteins during oxidative stress. The induction of protein carbonyl in fish was identified as a potentially useful biomarker of oxidative stress that warrants its application in the field investigations. [Copyright &y& Elsevier]

Phthalate esters such as di-butyl phthalate (DBP) and di-ethyl hexyl phthalate (DEHP) used in personal care and consumer products and medical devices have potential to affect human health. We studied the effect of DBP and DEHP on critical enzymes of glucocorticoid biosynthesis pathway in the adrenal gland and pro-inflammatory cytokines in the serum in male Wistar rats. DEHP and DBP treatment altered the mRNA expression of enzymes of glucocorticoid biosynthesis pathway accompanied by a reduction in glucocorticoid production and elevation in the level of glucocorticoid regulated pro-inflammatory cytokines indicating a cascading effect of phthalates. The analysis of PPI (protein – protein interaction) network involving Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) of enzymes through STRING database revealed that all the proteins have the maximum level of interaction with the selected number of proteins. The STRING database analysis together with in vivo data indicates the potential effects of phthalates on various targets of steroidogenesis pathway with a global biological impact. [Display omitted] • Phthalates (DBP and DEHP) caused histopathological injuries in rat adrenals. • Expression of enzymes of glucocorticoid biosynthesis was affected by DBP and DEHP. • Phthalates caused decrease in serum corticosterone but increase in cytokines. • PPI analysis revealed potential of phthalates to disrupt pathways in vital organs. [ABSTRACT FROM AUTHOR]