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br Valsartan It is another ARB with
Valsartan
It is another ARB, with several reports for its beneficial effects on CV system both in preclinical and clinical studies. Valsartan treatment has reduced the levels of pentraxin 3, a marker for inflammation and is well tolerated in terms of side effects [17]. In BSCORE study, 90-day second line treatment with valsartan produces significant downward shifts in residual total CV risk, in addition to improving BP outcomes, suggesting that it is highly effective in patients in whom prior treatment failed or was not tolerated, both in low risk and high risk patients according to the ESC-ESH risk classification [18]. Hypoxia inducible factor (HIF)-1a-mediated gene activation was detected in the kidneys in diabetic nephropathic rats, which was associated with the increases in pathogenic factors of diabetic nephropathy. Blockade of Ang II action using valsartan inhibited HIF-1a-mediated gene activation and decreased the associated pathogenic factors in diabetic nephropathy, thereby improving renal injury [19]. Apart from a few rare side effects reported, valsartan, either as a single drug or used in combination with other drugs, has a good tolerability suggesting its potential use with little caution. A report suggests that, valsartan impairs the Ang II-related angiogenesis of mice bone marrow stem Deacetylase Inhibitor Cocktail by inactivation of the AT1R/PI3K/Akt-related pathway [20]. Thus there may be a possible effect of valsartan during stem cell therapy for ischemic conditions, which needs future focus.
Irbesartan
Once daily treatment with irbesartan has been used for a long time, which produces effective BP control over 24h duration in essential hypertensive patients, which will be useful for morning hypertension as well as night hypotension. The IRIS-HF study has shown that irbesartan therapy on top of standard medical therapy improved impaired insulin sensitivity in HF patients [21]. Irbesartan completely blocked advanced glycation end-products (AGE)-induced ROS generation and vascular cell adhesion molecule (VCAM)-1 gene expression similar to N-Acetyl cysteine in human cultured glomerular microvascular endothelial cells [22]. Apart from the BP lowering effect, irbesartan can also influence the activation of PPARγ and which would be an additional beneficial effect in hypertensive patients suffering from metabolic abnormalities such as atherosclerosis. Since irbesartan has a good antihypertensive effect with nephroprotective as well as antioxidant properties, it can be used for the treatment of hypertensive patients with accompanied renal abnormalities.
Azilsartan
Azilsartan medoxomil, a recently approved ARB that is now available in the clinical arena for the treatment of hypertension, is a prodrug that is rapidly hydrolyzed to the active moiety azilsartan, which is a potent and selective antagonist of the AT1R. It slowly dissociates from the receptor and persistently inhibits the Ang II-induced accumulation of inositol 1,4,5-trisphosphate even after washout in Chinese hamster ovary cells that overexpress the human AT1R [23]. In addition, it has inverse agonistic property, which makes it a very attractive candidate for further pushing its clinical effects beyond simple BP control, potentially counteracting cardiac hypertrophy, cardiac fibrosis, and insulin resistance, together with improved renoprotection and atherosclerotic plaque stabilization particularly for patients who are unable to tolerate other antihypertensive drugs [24]. As it is a newer drug with fewer evidences for its effectiveness on CV morbidity and mortality, further studies are required to confirm its value against those ailments.
Fimasartan
The newly developed ARB, fimasartan, attenuated atherosclerosis progression and reduced macrophage accumulation in the rabbit aortic plaques, suggesting its value against arteriosclerosis in addition to antihypertensive effect [25]. Use of fimasartan, could prevent mitochondrial dysfunction and apoptosis accompanied by ischemia/reperfusion [26]. Fimasartan treatment with 60mg minimum effective dose was well tolerated, had a flat dose–response relationship and associated with significant decreases in BP in hypertensive patient populations of Korea, where once daily administration adequately maintained reductions in BP throughout the dosing interval [27]. The results suggest that fimasartan was superior to losartan in maintaining sitting diastolic BP. No initial dosage adjustments were required in patients receiving combination therapy with fimasartan and warfarin. Nevertheless, in female subjects or in patients with atherosclerotic conditions or long-term treatments, international normalized ratio (INR) monitoring should be continued in clinical practice [28].