Tohoku J. Exp. Med., 2021 January, 253(1)

Curcumin Mitigates Hypertension, Endothelial Dysfunction and Oxidative Stress in Rats with Chronic Exposure to Lead and Cadmium

Akarachai Tubsakul,¹ Weerapon Sangartit,¹ Poungrat Pakdeechote,¹ Veerapol Kukongviriyapan,² Kwanjit Apaijit³ and Upa Kukongviriyapan¹

¹Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
²Department of Pharmacology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
³Faculty of Medicine, Mahasarakham University, Mahasarakham, Thailand

Lead (Pb) and cadmium (Cd) are environmental pollutants and nonessential elements in the body. Both metals induce the development of hypertension which is associated with oxidative stress. Curcumin (CUR) is a polyphenolic compound with strong antioxidant activity. The present study evaluated the effect of CUR on oxidative stress, alteration of vascular responsiveness and hypertension induced by exposure to either Pb, Cd or the combination of Pb and Cd. Male Sprague-Dawley rats were exposed to low level of lead acetate (100 mg/L) and/or cadmium chloride (10 mg/L) in the drinking water for 16 weeks. The control animals received deionized water as drinking water. CUR (100 mg/kg) or propylene glycol as vehicle was intragastrically administered once daily for the last 4 weeks. Exposure to Pb, Cd or the combination induced increases in blood pressure and peripheral vascular resistance, and decreased the blood pressure response to intravenous infusion to acetylcholine. Supplementation with CUR significantly reduced blood pressure, alleviated oxidative stress, and increased plasma nitrate/nitrite and glutathione in the blood. The effects of CUR were associated with the improvement of vascular responsiveness, upregulation of the endothelial nitric oxide synthase and downregulation of the NADPH oxidase expression. Furthermore, CUR reduced the metal levels in blood, aorta, liver and kidney. Altogether, exposure to the combination of Pb and Cd aggravated hypertension and oxidative stress, and CUR effectively ameliorated these adverse events in metal exposed animals. Data indicate that CUR may be useful as a dietary supplement for protection against the noxious effects of the heavy metals.

Keywords —— cadmium; curcumin; hypertension; lead; oxidative stress

© 2021 Tohoku University Medical Press

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Tohoku J. Exp. Med 2021 253, 69-76.

Correspondence: Upa Kukongviriyapan, Ph.D., Department of Physiology, Faculty of Medicine, Khon Kaen University, 123 mittraphap. Road, Mueang Khon Kaen District, Khon Kaen 40002, Thailand.

e-mail: upa_ku@kku.ac.th