Quercetin prevents insulin dysfunction in hypertensive animals

Area of Science:

• Biochemistry
• Physiology
• Pharmacology

Background:

• Hypertension induced by Angiotensin II exacerbates oxidative stress, impairing insulin action and pancreatic function.
• Quercetin, found in rich foods, demonstrates antioxidant properties beneficial for conditions like hypertension and diabetes.

Purpose of the Study:

• To investigate the antioxidant effects of quercetin on insulin action, signaling, and secretion in a rat model of hypertension.
• To evaluate quercetin's impact on pancreatic function and metabolic parameters in hypertensive rats.

Main Methods:

• Wistar rats were divided into sham, hypertensive (H), and quercetin-supplemented hypertensive (HQ) groups.
• Hypertension was induced, followed by 30-day quercetin administration (50 mg/kg/day) in the HQ group.
• Insulin sensitivity, lipid peroxidation, pancreatic islet morphology, protein expression (muscarinic receptor type 3, VEGF, catalase), and hepatic gene expression (Ide) were assessed.

Main Results:

• Quercetin supplementation significantly reduced hypertension and serum lipid peroxidation levels.
• Improved insulin sensitivity was observed in adipose tissue, confirmed by insulin tolerance tests, HOMA index, and lipid profile.
• Quercetin treatment increased islet count, enhanced protein expression of key molecules within islets, and normalized hepatic Ide mRNA levels, despite normal insulin secretion.

Conclusions:

• Quercetin supplementation effectively ameliorates hypertension-associated oxidative stress and improves insulin action.
• The study demonstrates quercetin's protective role in preventing pancreatic and metabolic dysfunction in hypertensive rats.
• Quercetin shows potential as a therapeutic agent for managing metabolic complications associated with hypertension.