Antihypertensive and Antioxidant Action of Amlodipine and Vitamin C in Patients of Essential Hypertension

Abstract

Summary The etiology of essential hypertension includes increased oxidative stress. The role of antihypertensive drug amlodipine as an antioxidant and the benefit of addition of vitamin C, an antioxidant to antihypertensive therapy were studied. Forty male patients of essential hypertension were randomly divided into two groups and treated with 5 mg amlodipine. In addition one group also received 1000 mg vitamin C (as two 500 mg tablets) once daily for three months. Although blood pressure decreased in both groups, the systolic blood pressure in patients given vitamin C was less (126.4 ± 7.47) compared to the other group (130.9 ± 7.27). A decrease in malondialdehyde, an increase in erythrocyte sodium-potassium adenosine triphosphatase (Na + K + ATPase) and an increase in the superoxide dismutase levels were observed in both groups. The increase in SOD was statistically more in the patients given vitamin C in addition to amlodipine (0.1717 ± 0.0150 compared to 0.152 ± 0.0219 units/100 ml assay). In spite of the known antihypertensive, antioxidant activity, similarity in correcting endothelial dysfunction independently, giving the two drugs together and early introduction of vitamin C perhaps decreases oxidative stress and augments the antioxidant status. This may prevent further vascular damage due to oxidative stress, leading to a better prognosis in essential hypertension patients.

Nutraceuticals and Blood Pressure Control: Results from Clinical Trials and Meta-Analyses

“…Vitamin C also seems to improve the efficacy of effective antihypertensive drugs such as amlodipine [46]. In elderly patients with refractory hypertension already on maximum pharmacologic therapy, 600 mg of vitamin C daily lowered the BP by 20 ± 8/16 ± 5 mmHg [47].…”

Losartan improved respiratory function and coenzyme Q content in brain mitochondria of young spontaneously hypertensive rats

“…We could imply that antioxidant therapy itself could be effective enough in protection of brain tissue from the impairment in hypertension. In the literature there are studies using antioxidants for the treatment of hypertension in patients as well as in SHR (Mahajan et al 2007;Eshginia and Gapparov 2006;Czernichow et al 2005). Vitamin E supplementation significantly attenuated the increase in BP, intracellular calcium concentration, renal tissue aldehyde conjugates, and adverse renal vascular changes (Vasdev et al 2002) in SHR.…”

The role of nutrition and nutraceutical supplements in the treatment of hypertension

“…A serum level of 100 μmol/L is recommended [1,70,71] . The SBP and 24 ABM show the most significant reductions with chronic oral administration of Vitamin C [200][201][202][203][204][205] . Block et al [206] in an elegant depletion-repletion study of vitamin C demonstrated an inverse correlation of plasma ascorbate levels, SBP and DBP.…”

“…Vitamin C prevents ED induced by an oral glucose load. Vitamin C enhances the efficacy of amlodipine, decreases the binding affinity of the AT 1 receptor for angiotensin Ⅱ by disrupting the ATR1 disulfide bridges and enhances the anti-hypertensive effects of medications in the elderly Houston M. Hypertension, nutrition, nutritional supplements, cardiovascular disease with refractory hypertension [1,70,71,[200][201][202][203][204][205] . In elderly patients with refractory hypertension already on maximum pharmacologic therapy, 600 mg of vitamin C daily lowered the BP by 20/16 mmHg [205] .…”

“…Dietary intake of vitamin C and plasma ascorbate concentration in humans is inversely correlated to SBP, DBP and heart rate [196][197][198][199][200][201][202][203][204][205][206][207][208][209][210] . An evaluation of published clinical trials indicate that vitamin C dosing at 250 mg twice daily will significantly lower SBP 5-7 mmHg and diastolic BP 2-4 mmHg over 8 wk [196][197][198][199][200][201][202][203][204][205][206][207][208][209][210] . Vitamin C will induce a sodium water diuresis, improve arterial compliance, improve endothelial function, increase nitric oxide and PGI2, decrease adrenal steroid production, improve sympathovagal balance, increase RBC Na/K ATPase, increase SOD, improve aortic elasticity and compliance, improve flow mediated vasodilation, decrease pulse wave velocity and augmentation index, increase cyclic GMP, activate potassium channels, reduce cytosolic calcium and reduce serum aldehydes [208] .…”