title: Antioxidant and vascular protective effects of curcumin and tetrahydrocurcumin in rats with L-NAME-induced hypertension.
abstract: Inhibition of nitric oxide synthesis with N ( ω )-nitro-L-arginine methyl ester (L-NAME) induces marked hypertension and oxidative stress. Curcumin (CUR) has been shown strong antioxidant property. Tetrahydrocurcumin (THU), a major metabolite of CUR, possesses several pharmacological effects similar to CUR; however, it is less studied than CUR. We investigated whether CUR and THU could prevent vascular dysfunction and inhibit development of hypertension in L-NAME-treated rats. Male Sprague-Dawley rats were administered with L-NAME (50 mg/kg/day) in drinking water for 3 weeks. CUR or THU (50 and 100 mg/kg/day) was fed to animals simultaneously with L-NAME. L-NAME administration induced increased arterial blood pressure and elevated peripheral vascular resistance accompanied with impaired vascular responses to angiotensin II and acetylcholine. CUR and THU significantly suppressed the blood pressure elevation, decreased vascular resistance, and restored vascular responsiveness. The improvement of vascular dysfunction was associated with reinstating the marked suppression of eNOS protein expression in the aortic tissue and plasma nitrate/nitrite. Moreover, CUR and THU reduced vascular superoxide production, decreased oxidative stress, and increased the previously depressed blood glutathione (GSH) and the redox ratios of GSH in L-NAME hypertensive rats. The antihypertensive and some antioxidant effects of THU are apparently more potent than those of CUR. This study suggests that CUR and THU prevented the development of vascular dysfunction induced by L-NAME and that the effects are associated with alleviation of oxidative stress.
authors: Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.
authors: Saowanee
authors: S
authors: Nakmareong
authors: Upa
authors: U
authors: Kukongviriyapan
authors: Poungrat
authors: P
authors: Pakdeechote
authors: Wanida
authors: W
authors: Donpunha
authors: Veerapol
authors: V
authors: Kukongviriyapan
authors: Bunkerd
authors: B
authors: Kongyingyoes
authors: Kwanjit
authors: K
authors: Sompamit
authors: Chada
authors: C
authors: Phisalaphong
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D015153:Blotting, Western; D003474:Curcumin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D005978:Glutathione / Q000378:metabolism; D006973:Hypertension / Q000139:chemically induced / Q000188:drug therapy* / Q000201:enzymology / Q000503:physiopathology; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology*; D052250:Nitric Oxide Synthase Type III / Q000096:biosynthesis; D018384:Oxidative Stress / Q000187:drug effects; D050050:Protein Carbonylation; D051381:Rats; D017207:Rats, Sprague-Dawley; D014655:Vascular Resistance / Q000187:drug effects*
chemical_list: D000975:Antioxidants; C096277:tetrahydrocurcumin; D008315:Malondialdehyde; D052250:Nitric Oxide Synthase Type III; C496316:Nos3 protein, rat; D005978:Glutathione; D003474:Curcumin; D019331:NG-Nitroarginine Methyl Ester