University of Madras

About: University of Madras is a education organization based out in Chennai, Tamil Nadu, India. It is known for research contribution in the topics: Ring (chemistry) & Lipid peroxidation. The organization has 8496 authors who have published 11369 publications receiving 211152 citations. The organization is also known as: Madras University & University of Chennai.

Eutectic Solvent-Mediated Synthesis of NiFe-LDH/Sulfur-Doped Carbon Nitride Arrays: Investigation of Electrocatalytic Activity for the Dimetridazole Sensor in Human Sustenance

Abstract: Pharmaceutical contamination is an emerging environmental concern that threatens global health and impacts every hemisphere of existence. The extensive exploitation and unregulated release of these...

Effects of polychlorinated biphenyl (Aroclor 1254) on steroidogenesis and antioxidant system in cultured adult rat Leydig cells.

Abstract: Polychlorinated biphenyls (PCBs) are ubiquitous and persistent environmental contaminants that disturb normal endocrine functions, including gonadal functions in humans and mammals. In the present study, we examined the direct effects of PCB on rat Leydig cells in vitro. Adult Leydig cells were purified by Percoll gradient centrifugation method and the purity of Leydig cells was also determined by 3beta-hydroxysteroid dehydrogenase (3beta-HSD) staining method. Purified Leydig cells were exposed to different concentrations (10(- 10)-10(- 7) M) of PCB (Aroclor 1254) for 24 h under basal and LH-stimulated conditions. After the experimental period, cultured media were collected and used for the assay of testosterone and estradiol. The treated cells were used for the quantification of cell-surface LH receptors and activities of steroidogenic enzymes, such as cytochrome P(450) side-chain cleavage enzyme (P450scc), 3beta-HSD, and 17beta-hydroxysteroid dehydrogenase (17beta-HSD). Leydig cellular enzymatic antioxidants, such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, gamma-glutamyl transpeptidase, glutathione-S-transferase, and nonenzymatic antioxidants, such as vitamins C and E, were assayed. Lipid peroxidation (LPO) and reactive oxygen species (ROS) were also estimated in Leydig cells. In addition, total RNA was isolated from control and Aroclor 1254-exposed Leydig cells to monitor the steady-state mRNA levels by reverse transcription(RT)-PCR for steroidogenic acute-regulatory (StAR) protein, cytochrome P450scc, 3beta-HSD, and 17beta-HSD. Our results indicated that Aroclor 1254 (10(- 9), 10(- 8), and 10(- 7) M) treatments significantly inhibit basal and LH-stimulated testosterone and estradiol production. In addition, the activities of steroidogenic enzymes, enzymatic and nonenzymatic antioxidants were significantly diminished in a dose-dependent manner. However, LPO and ROS were elevated in a dose-dependent manner under basal and LH-stimulated conditions. RT-PCR analysis of StAR mRNA level showed a decrease only in 10(- 7) M dose of Aroclor 1254 treatment, while cytochrome P(450)scc, 3beta-HSD, and 17beta-HSD mRNAs were drastically decreased in both 10(- 8) and 10(- 7) M Aroclor 1254 treatment. These findings suggest that PCBs can act directly on Leydig cells to diminish testosterone production by inhibiting gene expression of steroidogenic enzymes and antioxidant system.