Garlic extract reduces serum angiotensin converting enzyme (ACE) activity in nondiabetic and streptozotocin-diabetic rats

Garlic (<i>allium sativum</i>) modulates the expression of angiotensin II AT<sub>2</sub> receptor in adrenal and renal tissues of streptozotocin-induced diabetic rats

“…This notion may be supported by the documented AT 2 -mediated activities in inhibiting aldosterone hypersecretion and regulating catecholamine levels in the adrenal gland [1,[7][8][9]49], inhibiting the sodium pump [53] and Na + -, K + -ATPase activity [20][21][22] in renal proximal tubules thereby promoting natriuresis/diuresis and hypotension, and inhibiting vasoconstriction and cell hypertrophy [7][8][9]18,19] thereby interfering with excessive renal glomerular and tubular remodeling. In this regard, our observations may lend support to the documented efficacy of garlic treatments in ameliorating diabetic complications in STZtreated rats [28][29][30][31][32][33][34][35][36] and further suggest that garlic may alleviate diabetic-induced hypertension and nephropathy by restoring the diabetic-induced loss of balance in AT 1 /AT 2 receptor expression in key target organs. Future studies on the significance of constituent garlic metabolites, acting individually or in concert, may clarify the mechanisms that underlie its beneficial capacity in modulating the expression of selective receptor molecules implicated in diabetes-associated disorders.…”

“…In experimental diabetes, sulfur-containing and non-sulfur constituents of garlic work synergistically to exhibit antithrombotic, antioxidant, hypocholesterolaemic, hypoglycaemic as well as hypotensive potentials, which collectively ameliorate the development and progression of diabetic complications, including nephropathy and hypertension [28][29][30][31][32][33][34][35][36]. Nonetheless, neither the precise mechanisms that underlie the anti-diabetic potentials of garlic nor the nature of the key receptor system(s) targeted, are fully understood.…”

“…In experimental diabetes, garlic, used either as a whole raw extract or as isolated organosulphur constituents, is one of the best studied herbal remedies with documented anti-diabetic activities [28][29][30][31][32]. These activities include lowering serum glucose and cholesterol levels [30,31,33], inhibiting Ang II and promoting vasodilatation [29], preventing adrenal hypertrophy [34], attenuating oxidative stress [35], inhibiting the formation of advanced glycation endproducts [36], ameliorating hypertension and delaying the progression of diabetic nephropathy [31,32,35,36]. Nonetheless, the potential of garlic in targeting the level of expression of Ang II receptors is, as yet, not fully explored.…”

Correlation of ACE gene deletion/insertion polymorphism and risk of pregnancy-induced hypertension: a meta-analysis based on 10,236 subjects

“…Human serum ACE is at the lowest level of activity in subjects with the II genotype. [55][56][57][58] To date, much research has been focused on the ACE gene I/D polymorphism and PIH, but the results are controversial. Aggarwal et al 27 found that although the level of activity of human serum ACE with the DD genotype was higher than that with other genotypes in northern India, in the distribution of genetic frequency there is no difference between the case and control groups.…”

Allicin, a SUR2 opener: possible mechanism for the treatment of diabetic hypertension in rats

“…DH 1 (allicin+nateglinide treated) and DH 2 (allicin+glibenclamide treated) shows potent antidiabetic activity, while rats of DH 3 (allicin) treated group shows less significant antidiabetic activity when compared with DH 1 and DH 2 groups ( allicin is given in combination with antidiabetic drugs, it shows the additive antidiabetic effect. Although earlier studies shown that garlic has a relaxant effect on vascular smooth muscle, which appears to be mediated through endothelium by increasing NO production (Ashraf et al, 2005;Oztiirk et al, 1994) some studies suggested that garlic extract might have value as ACE inhibitor to prevent hypertension (Hosseini et al, 2007;Sharifi et al, 2003). Antioxidant as well as antidiabetic effect of garlic (El-Demerdash et al, 2005;Shariatzadeh et al, 2008;Drobiova et al, 2009) might be responsible for antihypertensive effect because oxidative stress is major cause of hypertension in diabetic patient (De Champlain et al, 2004;Ceriello, 2008;Drobiova et al, 2009).…”