Biology subjects

Ravi, D. B.

Publications and source records attributed to Ravi, D. B..

4 recordsLinked to original sources

bioRxiv2025

Oxidative stress and Atherosclerotic Plaque Progression: A plausible insight into the role of paraxonases and Ox-LDL

The atherosclerotic heart disease is a complex disease associated with a plethora of dynamics contributing to its initiation and progression. Despite, diabetes and hypertension provide favorable conditions that provoke and aggravate atherosclerosis, it is undeniable that all of them do not have the tendency to develop plaques. This study was devised to identify the attributes that discriminate the diabetic and/or hypertensive ischemic patients from their corresponding non-ischemic population. Serum total antioxidant status, ox-LDL levels, Paraoxonase levels and its activity were assessed in the study groups. In order to evaluate the extent of the atherosclerotic disease progression, the aortic punch tissue samples from patients undergoing CABG were analyzed for the expression of ox-LDL and PON-2. Our results showed that their serum levels correlated well with the tissue expression. To ascertain the same with the progression of the disease, animal studies with rats fed with High Cholesterol Diet were carried out. Our findings suggests that ox-LDL and HDL-PON activity reflects the atherogenic events taking place in the arteries and further assessment of atherosclerotic risk in terms of ox-LDL and PON might be recommended after further validation.

biochemistry↗

bioRxiv2025

Temporal changes in miR-23a-5p levels in subclinical atherosclerosis: A Potential biomarker.

A high-cholesterol diet (HCD) is a well-established contributor to oxidative stress, inflammation, and atherogenesis, yet the temporal progression of these pathological changes and the regulatory role of circulating microRNAs (miRNAs) remain incompletely understood. In this study, we investigated the effects of prolonged HCD exposure to rats on lipid metabolism, oxidative stress, inflammation, endothelial dysfunction, and miRNA expression in a rat model. Male Wistar rats were fed either a standard diet or HCD for 30, 60, 90, or 120 days. Biochemical analyses revealed a progressive dyslipidemic profile characterized by elevated total cholesterol, triglycerides, LDL, VLDL, and atherogenic index, alongside a significant reduction in HDL. Lipid peroxidation levels increased markedly with HCD duration, while antioxidant markers PON1 and ApoA1 were significantly reduced and oxLDL levels were elevated. Inflammatory cytokines (CRP, TNF-, IL-6, IL-8) and VCAM-1 were significantly increased, indicating systemic inflammation and endothelial activation. Notably, miR-23a-5p and miR-15b-5p were elevated in the serum of HCD-fed rats, with miR-23a-5p peaking at day 120. Correlation analyses revealed that miR-23a-5p expression positively correlated with oxLDL and inversely with ApoA1 and PON1 levels, suggesting its involvement in oxidative and lipoprotein dysregulation. These findings demonstrate that prolonged HCD induces a coordinated cascade of oxidative, inflammatory, and lipoprotein alterations, with miR-23a-5p emerging as promising biomarkers and potential regulators of redox and lipid homeostasis in atherogenesis.

molecular biology↗

bioRxiv2019

CHOLESTEROL MYTH AND THE IMPERATIVE ROLE OF FUNCTIONAL EVALUATION OF LIPOPROTEINS IN ATHEROSCLEROTIC RISK PREDICTION STRATEGIES

ObjectiveTo arrive at apposite risk prediction strategies in identifying markers that could delineate patients susceptible for atherosclerotic progression from other diabetic patient population thus circumventing undesirable drug exposure or conversely inadequate treatment. Research Design and MethodsThe study was designed to assess and compare the biochemical parameters along with lipoprotein ratios assessed in structural and functional aspects between the probable risk factor groups for CAD(diabetics with no symptoms for CAD) and untreated CAD patients (on admission for CAD) in a total of 593 participants. Anthropometric measurements were made and serum fasting glucose, lipid peroxide levels, lipid and lipoprotein ratio assessments were carried out. In addition to these basic parameters, oxidized LDL (Ox-LDL) and serum paraoxonase (PON) activity were also measured in this study. To ascertain the diagnostic accuracy of the individual markers, receiver operating characteristic curve analysis was carried out. ResultsSerum levels of blood lipids, lipid peroxides were higher in the diabetic and the cardiovascular patients with a concomitant decrease in the levels of HDL. Increased median levels of Ox-LDL and decreased PON activity was observed in the cardiovascular patients both with and without diabetes. ConclusionThis study proposes Ox-LDL/PON assessment would be more functional than the traditional LDL-c/HDL-c to categorize the risk group of patients into prospective atherosclerotic predisposed and non-predisposed population, thus enabling the former to get treated with appropriate medication.

biochemistry↗

bioRxiv2018

Scopoletin Augments DJ1/Nrf2 Signalling and Prevents Protein Aggregation in Parkinson’s disease

Given the role of oxidative stress in PD pathogenesis and off-target side effects of currently available drugs, several natural phytochemicals seems to be promising in the management of PD. Here, we tested the hypothesis that scopoletin, an active principle obtained from Morinda citrifolia (MC), efficiently quenches oxidative stress through DJ-1/Nrf2 signalling and ameliorates rotenone-induced PD. Despite reducing the oxidative stress, administration of MC extract (MCE) has lessened the protein aggregation as evident from decreased levels of nitrotyrosine and -Synuclein. In vitro studies revealed that scopoletin lessened rotenone-induced apoptosis in SH-SY5Y cells through preventing oxidative injury. Particularly, scopoletin markedly up-regulated DJ-1, which then promoted the nuclear translocation of Nrf2 and transactivation of antioxidant genes. Furthermore, we found that scopoletin prevent the nuclear exportation of Nrf2 by reducing the levels of Keap1 and thereby enhancing the neuronal defence system. Overall, our findings suggest that scopoletin acts through DJ-1 mediated Nrf2 signalling to protect the brain from rotenone-induced oxidative stress and PD. Thus, we postulate that scopoletin could be a potential drug to treat PD.

biochemistry↗