Publications by authors named "Sundaram Ramalingam"

The synaptic vesicle protein Synaptophysin has long been known to form a complex with the v-SNARE VAMP, but a more specific molecular function or mechanism of action in exocytosis has been lacking because gene knockouts have minimal effects. Utilizing fully-defined reconstitution and single-molecule measurements, we now report that Synaptophysin functions as a chaperone that determines the number of SNAREpins assembling between a ready-release vesicle and its target membrane bilayer. Specifically, Synaptophysin directs the assembly of 12 ± 1 SNAREpins under each docked vesicle, even in the face of an excess of SNARE proteins.

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Article Synopsis
  • Current methods struggle with accurately measuring the first- and second-phase insulin secretion dynamics, which are important for metabolism, leading researchers to seek new approaches.
  • A novel insulin-nanoluc luciferase reporter system was created to separately analyze the phases of insulin secretion and tested through various genetic studies and small-molecule screenings.
  • The new method shows strong correlation with traditional live-cell experiments, offering a powerful tool for understanding and improving insulin therapy by enhancing glucose-stimulated insulin secretion.
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The aim of the present study was to evaluate the effects of chebulagic acid on enzymes involved in carbohydrate metabolism in high-fat diet/streptozotocin-induced diabetic rats. Diabetes was induced in albino male Wistar rats by feeding them with a high-fat diet comprising of 84.3% standard laboratory rat chow, 5% lard, 10% yolk powder, 0.

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Linn. ( Anacardiaceae), commonly known marking nuts has been used in various traditional system of medicines for various ailments (such as antiatherogenic, antiinflammatory, antimicrobial, hypoglycemic, anticarcinogenic etc) since ancient times.Based on the wide pharmacological activities of this plant, the present study was aimed to explore the antioxidant and antihyperlipidemic potential in high fat diet fed rats using catechol derivatives I-IV and biflavonoid isolated from seeds of .

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(family: Acanthaceae) is a medicinal herb-used in Indian system of medicine (Ayurveda, Siddha, and Unani), traditional and folk systems to treat various illnesses. This study examined the phytochemical constituents of ethanol extract from and its protective effect against genotoxicity caused by cyclophosphamide (CPA). Phytochemical screening and estimation of total phenolic content were analyzed using standard methods.

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The present study was aimed to investigate the effect of black tea extract on blood glucose, plasma insulin, Hemoglobin, carbohydrate metabolic enzymes and tricarboxylic enzymes in streptozotocin (STZ) induced diabetic rats. Diabetes was induced in male albino Wistar rats by intraperitoneal administration of STZ (40 mg/kg b wt). Black tea extract was administered to diabetic rats at a dose of 25, 50 and 100 mg/kg body weight for 30 days.

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Ethnopharmacological Relevance: β-Sitosterol is a plant derived compound similar to cholesterol structure and used in the treatment of hypercholesterolemia, prostate cancer, breast cancer and coronary artery disease. But no studies have been reported the effect of β-sitosterol on glucose homeostasis by sensitization of insulin resistance via enhanced protein expression of peroxisome proliferator-activated receptor γ (PPARγ) and glucose transporter 4 (GLUT4) in insulin dependent tissues of high fat diet and streptozotocin-induced diabetic rats.

Materials And Methods: Type 2 diabetes was induced in male albino Wistar rats by feeding them with high fat diet comprising of 84.

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The present study was to isolate the biflavonoid (a bimolecular kaemferol structured molecule) and test its efficacy on oxidative stress and carbohydrate metabolic key enzymes in control and high fat diet and streptozotocin -induced diabetic rats. Type 2 diabetes was induced in male albino wistar rats by feeding them with high fat diet comprising of 84.3% standard laboratory chow, 5% lard, 10% yolk powder, cholesterol 0.

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The present study was aimed to explore the antihyperlipidemic and anti-inflammatory effect of acyclic isoprenoid on high fat diet fed rats. Hypercholesterolemia was induced by the diet comprising of the normal rat chow 84.3%, lard 5%, yolk powder 10%, cholesterol 0.

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The present study was to evaluate the effect of theaflavin on the activities of key enzymes of carbohydrate metabolism in high fat diet and streptozotocin - induced diabetic rats. Diabetes was induced in male albino Wistar rats by feeding them with high fat diet comprising of standard laboratory rat chow 84.3%, lard 5%, egg yolk powder 10%, cholesterol 0.

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Background: Theaflavins are major polyphenols in black tea which is the most widely consumed tea in the world. They possess a broad spectrum of biological activities, such as antioxidant, anti-tumor, anti-inflammatory, and cardio-protective effects. The present study was aimed to evaluate the protective effect of theaflavin on glycoprotein content and tricorboxylic acid cycle enzymes in high-fat diet and streptozotocin-induced diabetic rats as there was no study on this aspect.

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The present study was aimed at evaluating the acute and subacute toxicity of catechol derivatives (I-IV, isolated from S nuts) in Wistar Albino rats. In acute study (14 days), catechol derivatives I-IV 800 mg/kg caused no behavioral adverse effects and mortality. Fifty percent (LD) of mortality was observed in catechol derivatives I-III (1600 mg/kg b.

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Objectives: Linn. is a plant well-known for its antimicrobial, antidiabetic and anti-arthritic properties in the Ayurvedic and Siddha system of medicine. This has prompted the screening of this plant for antibacterial activity.

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HIV-1 Env protein is essential for host cell entry, and targeting Env remains an important antiretroviral strategy. We previously found that a peptide triazole thiol KR13 and its gold nanoparticle conjugate AuNP-KR13 directly and irreversibly inactivate the virus by targeting the Env protein, leading to virus gp120 shedding, membrane disruption and p24 capsid protein release. Here, we examined the consequences of targeting cell-surface Env with the virus inactivators.

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Solid-state nanopores have been widely used in the past for single-particle analysis of nanoparticles, liposomes, exosomes and viruses. The shape of soft particles, particularly liposomes with a bilayer membrane, can greatly differ inside the nanopore compared to bulk solution as the electric field inside the nanopores can cause liposome electrodeformation. Such deformations can compromise size measurement and characterization of particles, but are often neglected in nanopore resistive pulse sensing.

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The present study was designed to evaluate the antihyperglycemic potential of tangeretin on the activities of key enzymes of carbohydrate and glycogen metabolism in control and streptozotocin induced diabetic rats. The daily oral administration of tangeretin (100mg/kg body weight) to diabetic rats for 30 days resulted in a significant reduction in the levels of plasma glucose, glycosylated hemoglobin (HbA1c) and increase in the levels of insulin and hemoglobin. The altered activities of the key enzymes of carbohydrate metabolism such as hexokinase, pyruvate kinase, lactate dehydrogenase, glucose-6-phosphatase, fructose-1,6-bisphosphatase, glucose-6-phosphate dehydrogenase, glycogen synthase and glycogen phosphorylase in liver of diabetic rats were significantly reverted to near normal levels by the administration of tangeretin.

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The present study was designed to examine the antihyperlipidaemic potential of iridoid glucoside isolated from Vitex negundo leaves in STZ-induced diabetic rats. The levels of cholesterol (TC), triglycerides, lipoproteins, free fatty acids, phospholipids, fatty acid composition, proinflammatory cytokines, muscle glycogen content, and glucose transporter 4 (GLUT4) expression were estimated in control and diabetic rats. Oral administration of iridoid glucoside at a dose of 50 mg/kg body weight per day to STZ-induced diabetic rats for a period of 30 days resulted in a significant reduction in plasma and tissue (liver and kidney) cholesterol, triglycerides, free fatty acids, and phospholipids.

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The study was undertaken to evaluate the antidiabetic effect of green tea extract on carbohydrate metabolic key enzymes in control and streptozotocin high fat diet -induced diabetic rats. The daily oral treatment of green tea extract (300 mg/kg body weight) to diabetic rats for 30 days resulted in a significant reduction in the levels of plasma glucose, glycosylated hemoglobin (HbA1c) and increase in the levels of insulin and hemoglobin. The altered activities of the key enzymes of carbohydrate metabolism such as hexokinase, pyruvate kinase, lactate dehydrogenase, glucose-6-phosphatase, fructose-1,6-bisphosphatase, glucose-6-phosphate dehydrogenase, glycogen synthase and glycogen phosphorylase in liver of diabetic rats were significantly reverted to near normal levels by the administration of green tea extract.

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Hyperlipidemia is an associated complication of diabetes mellitus. The association of hyperglycemia with an alteration of lipid parameters presents a major risk for cardiovascular complications in diabetes. The present study was designed to examine the antihyperlipidemic effect of 20-OH ecdysone on lipid profile and tissue fatty acid changes in streptozotocin induced diabetic rats.

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The aim of the present investigation was to evaluate the anti-diabetic activity of 20-OH-ecdysone on glucose metabolic key enzymes in control and streptozotocin induced diabetic rats. On oral administration of 20-OH-ecdysone at a dose of 5mg/kg body weight per day to diabetic rats for 30 days resulted in a significant decrease in the levels of plasma glucose, glycosylated hemoglobin (HbA1c) and an increase in the levels of insulin and hemoglobin. Administration of 20-OH-ecdysone showed significant increase in the levels of glycolytic enzyme (hexokinase) and hepatic shunt enzyme (glucose-6-phosphate dehydrogenase) whereas significant decrease in the levels of gluconeogenic enzymes (glucose-6-phosphatase and fructose-1,6-bisphosphatase) in diabetic treated rats.

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The aim of present study was to isolate an iridoid glucoside from the leaves of Vitex negundo and evaluates its effects on dearrangement in plasma and tissues glycoprotein components in streptozotocin-induced diabetic rats. The levels of blood glucose, plasma and tissues glycoproteins such as hexose, hexosamine, fucose and sialic acid were significantly increased whereas plasma insulin levels were significantly decreased in diabetic rats. On oral administration of iridoid glucoside at a concentration of 50 mg/kg b.

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Vitex negundo is a medicinal plant used to treat many ailments. An active compound of iridoid glucoside was isolated from V. negundo leaves and its efficacy was investigated in streptozotocin induced diabetic rats with special reference to carbohydrate metabolizing enzymes.

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The aim of this study is to investigate the mechanism of an action of compound isolated from Vitex negundo in streptozotocin-induced diabetic mice. Light microscopic examination of liver, kidney and pancreatic sections of streptozotocin-induced diabetic mice showed changes like coarsening of acinar cells of endoplasmic reticulum, destruction of β-cells, and alteration in their secretory function were observed in the pancreas. Changes like dilation of vein, unusual concentric arrangement of hepatocytes, and liver fibrosis were observed in the liver.

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The aim of the present study is to evaluate the effect of hot water extract of black tea in regenerating beta cells in streptozotocin-induced diabetic mice. Light microscopic examination of pancreatic sections of streptozotocin-induced diabetic mice showed the acinar cells to be small, shrunken, and with deteriorated beta cells. The dose of streptozotocin not only altered the function of beta cells but also damaged the acinar region.

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