An investigation into the effect of sulfonylurea glyburide on glutathione peroxidase activity in streptozotocin-induced diabetic rat muscle tissue

Glibenclamide impairs responses of neutrophils against Burkholderia pseudomallei by reduction of intracellular glutathione

The major risk factor for melioidosis, an infectious disease caused by B. pseudomallei, is diabetes mellitus. More than half of diabetic melioidosis patients in Thailand were prescribed glibenclamide. Recent evidence demonstrates that glibenclamide reduces pro-inflammatory cytokine production by polymorphonuclear neutrophils (PMNs) of diabetic individuals in response to this bacterial infection. However, the mechanisms by which glibenclamide affects cytokine production are unknown. We found that PMNs from glibenclamide-treated diabetic individuals infected with live B. pseudomallei in vitro showed lower free glutathione (GSH) levels compared with those of healthy individuals. Glibenclamide decreased GSH levels and glutathione peroxidase (GPx) of PMNs after exposed to live B. pseudomallei. Moreover, glibenclamide reduced cytokine production and migration capacity of infected PMNs, whereas GSH could restore these functions. Taken together, our data show a link between the effect of glibenclamide on GSH and PMN functions in response to B. pseudomallei that may contribute to the susceptibility of diabetic individuals to B. pseudomallei infection.

Protective role of glibenclamide against nicotinamide-streptozotocin induced nuclear damage in diabetic Wistar rats

Objective:

To evaluate the protective effect of glibenclamide against the experimental diabetes-induced nuclear damage in Wistar rats.

Materials and Methods:

The anti-mutagenic effect of glibenclamide (0.5, 5 and 50 mg/kg, p.o daily for 4 weeks) was evaluated against the nicotinamide (NA)-streptozotocin (STZ) induced type-2 diabetes mellitus using bone marrow micronucleus and sperm abnormalities tests. The antioxidant status was tested by estimating the serum levels of lipid peroxidation (LPO), catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx).

Results:

The results indicated that glibenclamide at 50 mg/kg decreased the frequency of micronuclei in erythrocytes (P < 0.05) and sperm shape abnormality (P < 0.01) besides enhancing the antioxidant status (P < 0.05) in the diabetic rats. However, glibenclamide treatment did not enhance the polychromatic and normochromatic erythrocytes (P/N) ratio and sperm count in the diabetic condition.

Conclusion:

The observations indicate that the glibenclamide has anti-mutagenic potential which could be related to the antioxidant effect and might also possess anti-proliferative property.

THE ATP-SENSITIVE POTASSIUM-CHANNEL INHIBITOR GLIBENCLAMIDE IMPROVES OUTCOME IN AN OVINE MODEL OF HEMORRHAGIC SHOCK

This study was designed as a prospective laboratory experiment to evaluate the effects of the ATP-sensitive potassium-channel inhibitor glibenclamide on hemodynamics and end-organ function in an ovine model of hemorrhagic shock. Twenty-four adult sheep were anesthetized and surgically prepared to measure hemodynamics of the systemic and pulmonary circulation. The anterior surface of the abdominal aorta was exposed at a location 6 cm superior to the iliac bifurcation. After a 60-min period of stabilization, this location was punctured with a 14-G needle. To induce a hemorrhagic hypotension (mean arterial pressure [MAP] less than 50 mmHg) via bleeding, the needle was left in place for 15 s to insure good blood flow. Thereafter, it was removed, and the abdomen closed. The animals were then randomized to receive either glibenclamide (4 mg/kg over 15 min) or an equal volume of the vehicle, started 1 h postinjury. Hemodynamic variables were measured every 30 min. Compared with the control group, MAP and systemic vascular resistance index (SVRI) were significantly higher in the intervention group throughout the entire 6-h study period. Ileal pH and urine output were higher in treated than in control animals (4 h, ileal pH 7.29 +/- 0.31 vs. 7.17 +/- 0.6; 6 h, urine output 36 +/- 9 vs. 7.5 +/- 2 mL; P value less than 0.05 each). Because glibenclamide improved both hemodynamics and organ function, it may be a beneficial component in the acute treatment of hemorrhagic shock.

A diabetes outcome progression trial (ADOPT): an international multicenter study of the comparative efficacy of rosiglitazone, glyburide, and metformin in recently diagnosed type 2 diabetes

OBJECTIVE

Therapies with metformin, sulfonylureas, or insulin improve glycemic control in the short term but do not prevent progressive islet beta-cell failure or long-term deterioration in glycemia. Our goal was to evaluate, in patients recently diagnosed with type 2 diabetes (<3 years), the long-term efficacy of monotherapy with rosiglitazone on glycemic control and on the progression of pathophysiological abnormalities associated with type 2 diabetes as compared with metformin or glyburide monotherapy.

RESEARCH DESIGN AND METHODS

A Diabetes Outcome Progression Trial (ADOPT) is a randomized, double-blind, parallel-group study consisting of a screening visit, a 4-week placebo run-in, a 4-year treatment period, and an observational follow-up of approximately 3,600 drug-naïve patients with type 2 diabetes diagnosed within the previous 3 years. After run-in, patients will be randomized to rosiglitazone, glyburide, or metformin titrated to the maximum effective daily doses (8 mg rosiglitazone, 15 mg glyburide, or 2 g metformin). The primary outcome is time to monotherapy failure, defined as the time following titration to the maximal effective or tolerated dose when fasting plasma glucose exceeds 180 mg/dl (10 mmol/l). Secondary outcomes include measures of islet beta-cell function, insulin sensitivity, dyslipidemia, changes in urinary albumin excretion, plasminogen activator inhibitor-1 antigen, fibrinogen, and C-reactive protein. Safety and tolerability will also be evaluated. Patient-reported outcomes and resource utilization data will be collected and analyzed.

CONCLUSIONS

ADOPT will provide data on the effect of mechanistically differing treatment options on metabolic control, beta-cell function, and markers of macrovascular disease risk in type 2 diabetes.