Chrysin and Luteolin Attenuate Diabetes‐Induced Impairment in Endothelial‐Dependent Relaxation: Effect on Lipid Profile, AGEs and NO Generation

Abstract

Chrysin and luteolin are two important plant flavonoids. In the present study, we hypothesized that they protect against deleterious vascular effects of diabetes. Diabetes was induced in rats by streptozotocin (STZ) injection, while chrysin and luteolin were administered two weeks after STZ administration for 6 weeks. Then, blood pressure (BP) and serum levels of glucose, advanced glycation end products (AGEs), triglycerides (TGs), total cholesterol and low density lipoprotein-cholesterol (LDL-C) were determined. Concentration response curves for KCl, phenylephrine (PE), acetylcholine (ACh) and ACh-induced NO generation were obtained in isolated aorta. Compared with control, diabetes increased diastolic and systolic BP, while chrysin and luteolin attenuated diastolic BP elevation without affecting the developed hyperglycemia. Diabetes increased contractile response of aorta to KCl, PE, decreased relaxation response to ACh, while chrysin and luteolin prevented the impaired response to ACh. In addition, diabetes was accompanied by elevated levels of TGs, total and LDL cholesterol, while both chrysin and luteolin prevented this dyslipidemia. Furthermore, chrysin decreased the elevated AGEs level in serum of diabetic animals, while luteolin abrogated the impaired NO generation in diabetic aorta. Collectively, chrysin and luteolin attenuate diabetes-evoked impairment in endothelial-dependent relaxation possibly via ameliorating detrimental changes in lipid profile, AGEs and NO generation.

Chrysin, baicalein and galangin are indirect activators of the human constitutive androstane receptor (CAR)

“…CAR activation is associated with many beneficial effects on the metabolism of glucose and lipids. Baicalin, baicalein, galangin and chrysin have been reported to ameliorate high glucose and lipids levels in various experimental models, with various molecular mechanisms having been proposed for the activities (El-Bassossy et al, 2013;Guo et al, 2009;Kumar and Alagawadi, 2013;Sivakumar et al, 2010;Waisundara et al, 2009). A more detailed characterization of the molecular effects of the studied flavonoids would help us consider their clinical applications in the treatment of highly prevalent illnesses such as obesity, hypercholesterolemia and type 2 diabetes.…”

Protective Effects of Chrysin Against Drugs and Toxic Agents

“…59 The protective effects of CH against oxidative damage in the serum of STZ diabetic rats were assessed. Chrysin ameliorated an elevation in glucose, MDA, triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C), and a reduction in high-density lipoprotein cholesterol (HDL-C), total protein, SOD, CAT, and GST in the serum of rat received STZ.…”

Normal Vascular Reactivity Is Restored by Apigenin in Diabetic Rats

“…The isolated artery technique comprehensively addressed in [12][13][14][15][16][17][18] was applied to undertake vascular reactivity of isolated thoracic aortas. The rise in tension caused by increasing addition of phenylephrine (PE, 10 -9 to 10 -5 M) or KCl (10 to 100 mmol) formed the basis for the evaluation of aortic ring contraction.…”