Vasorelaxant effect of 5,7,4′- Trihydroxyflavanone (Naringenin) via endothelium dependent, potassium and calcium channels in Sprague Dawley rats: Aortic ring model

• Published in: Chemico-biological interactions Vol. 348; p. 109620
• Main Authors: Tan, Chu Shan, Tew, Wan Yin, Jingying, Chen, Yam, Mun Fei
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 01-10-2021
• Subjects: Animals; Aorta - drug effects; Aorta - metabolism; Aortic ring assay; Calcium - metabolism; Calcium and potassium channels; Calcium Channels - metabolism; Endothelium, Vascular - drug effects; Endothelium, Vascular - metabolism; Flavanones - pharmacology; Flavonoids; Male; Naringenin; Phenylephrine - pharmacology; Potassium Channels - metabolism; Rats; Rats, Sprague-Dawley; Vasodilation - drug effects; Vasodilator Agents - pharmacology; Vasorelaxation; Calcium and potassium channels; Flavonoids; Aortic ring assay; Naringenin; Vasorelaxation
• ISSN: 0009-2797; 1872-7786; 1872-7786
• DOI: 10.1016/j.cbi.2021.109620

Naringenin is a naturally occurring flavanone (flavonoid) known to have bioactive effects on human health. It has been reported to show cardiovascular effects. This study aimed to investigate the possible vasorelaxant effect of naringenin and the mechanism behind it by using a Sprague Dawley rat aortic ring assay model. Naringenin caused significant vasorelaxation of endothelium-intact aortic rings precontracted with phenylephrine (pD2 = 4.27 ± 0.05; Rmax = 121.70 ± 4.04%) or potassium chloride (pD2 = 4.00 ± 0.04; Rmax = 103.40 ± 3.82%). The vasorelaxant effect decreased in the absence of an endothelium (pD2 = 3.34 ± 0.10; Rmax = 62.29 ± 2.73%). The mechanisms of the vasorelaxant effect of naringenin in the presence of antagonists were also investigated. Indomethacin, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, atropine, 4-aminopyridine, Nω-nitro-l-arginine methyl ester, glibenclamide and propranolol significantly reduced the relaxation stimulated by naringenin in the presence of endothelium. Besides that, the effect of naringenin on the voltage-operated calcium channel (VOCC) in the endothelium-intact aortic ring was studied, as was intracellular Ca2+ release from the sarcoplasmic reticulum (SR) in the endothelium-denuded aortic ring. The results showed that naringenin also significantly blocked the entry of Ca2+ via the VOCC, SERCA/SOCC and suppressed the release of Ca2+ from the SR. Thus, the vasorelaxant effect shown by naringenin mostly involve the COX pathway, the endothelium-dependent pathway via NO/sGC/prostaglandin, calcium and potassium channels.
•Naringenin exhibited strong vasorelaxant effect on endothelium-intact aortic ring.•Vasorelaxant effect of naringenin take part in NO/sGC/prostaglandin pathway.•Vasorelaxant effect employed by naringenin were mostly via optimising of channel-linked receptor pathway.