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Biology subjects

Pandey, K. K.

Publications and source records attributed to Pandey, K. K..

2 recordsLinked to original sources

Curcumin alleviates Arsenic trioxide-induced behavioural impairment, oxidative damage & morphological alterations in striatal region of mice brain

Arsenic-induced neurotoxicity is well-documented in literature and reported to have dose-dependent damaging effects in the mice brain. Curcumin, a cost-effective plant polyphenol, safely demonstrates protective effects against arsenic-induced neurotoxicity by modifying oxidative stress, apoptosis, and neurochemistry in rodents brain. The present study determined the neuroprotective potential of curcumin (CUR) on adverse effects induced by arsenic trioxide (As2O3) in mice striatal region. Healthy adult male mice were chronically administered with varying concentrations of As2O3 (2, 4 & 8 mg/kg bw) alone and along with CUR (100 mg/kg bw) via oral route for 45 days. Towards the end of experimental period, the animals were subjected to behavioural paradigm including open field task, novel object recognition, rota-rod and morris water maze. Fresh striatal tissues were collected from the animals on day 46 for biochemical analysis such as MDA, GPx and GSH. While perfusion fixed brains were processed for morphological observations. Behavioural study showed an apparent decrease in certain cognitive functions (learning and memory) and locomotor activity in mice exposed to As2O3 compared to controls. Simultaneous treatment of As2O3 (2, 4 & 8 mg/kg bw) and curcumin (100 mg/kg bw) alleviated the As-induced locomotor and cognitive deficits. As2O3 alone exposure also exhibited a significant increase in oxidative stress marker (MDA) and decrease in antioxidant enzyme levels (GPx, GSH). Morphological alterations were noted in mice subjected to elevated doses of As2O3 (4 & 8 mg/kg bw). However, these changes were reversed in mice who received As2O3 + CUR co-treatment. Together, our findings provide preliminary evidence that curcumin protects mice striatal region from As2O3-induced behavioral, biochemical and morphological alterations.

pharmacology and toxicology↗

Molecular determinants for Rous sarcoma virus intasome assemblies

Integration of retroviral DNA into the host genome involves formation of integrase (IN)-DNA complexes termed intasomes. Here, we report the single-particle cryo-EM structure of the Rous sarcoma virus (RSV) strand transfer complex (STC) intasome produced with IN and a preassembled viral/target DNA substrate. The STC structure had an overall resolution of 3.36 [A] and 3 [A] in the conserved intasome core (CIC) region. Our structure demonstrated the flexibility of the distal IN subunits relative to the IN subunits in the CIC, similar to previously shown with the RSV octameric cleaved synaptic complex (CSC) intasome produced with IN and viral DNA only. An extensive analysis of higher-resolution STC structure helped in identification of nucleoprotein interactions important for intasome assembly. Using structure-function studies, we determined the mechanisms of several IN-DNA interactions critical for assembly of both RSV intasomes. We determined the role of IN residues R244, Y246 and S124 in CSC and STC intasome assemblies and their catalytic activities, demonstrating differential effects. Taken together, these studies advance our understanding of different RSV intasome structures and molecular determinants involved in their assembly.

biochemistry↗