br Telmisartan Telmisartan is one of the widely used

Telmisartan Telmisartan is one of the widely used antihypertensive agents, which has demonstrated favorable safety and tolerability profiles, both alone and in combination therapies. It has a number of pharmacological properties that distinguish it from other ARBs—the longest plasma half-life, highest lipophilicity and strongest receptor binding affinity in class. Telmisartan is, therefore has a broad indication for CV risk reduction in patients with atherothrombotic disease or Dehydroandrographolide (DM) with end-organ damage [5]. Telmisartan can effectively improve insulin sensitivity in patients with hypertension and because of its additive PPARγ agonistic action, it can improve vascular inflammation, reduce visceral fat, and increase serum adiponectin along with reducing the elevated BP in essential hypertensive patients [6]. A meta-analysis revealed that, telmisartan therapy may reduce left ventricular (LV) mass index over other antihypertensive drug therapies in patients with hypertension and it was mostly unrelated to its BP lowering effect [7]. Thus, we should consider the additional benefits offered by telmisartan therapy such as PPARγ agonistic actions as well as stimulating effect on adiponectin production so that the patients can be benefited by these effects.
Olmesartan Olmesartan is another AT1R antagonist used for more than a decade and has a favorable safety and efficacy profile in the treatment of hypertension. It has a special double-chain domain that makes it an effective antihypertensive agent when compared with the other ARBs. Similar to telmisartan, treatment with olmesartan has also increased adiponectin levels and this might improve insulin sensitivity and produce anti-atherogenic and anti-inflammatory effects in patients with diabetic nephropathy [8]. There are reports for its adverse events such as sprue-like enteropathy and mortality risk. But, Catala-Lopez et al. [9] analyzed those reports and suggested the benefits of olmesartan treatment in patients with diabetic albuminuria. Another study suggested that olmesartan therapy confers improved long-term clinical outcomes, but the atheroma volume changes could be a reliable surrogate for future major adverse cardio- and cerebro-vascular events [10]. Randomized and observational studies have shown that olmesartan provides effective BP control in a single dose per day regimen in the elderly patients. It also has a good tolerability profile, a pharmacokinetic profile unaffected by age and a low propensity for drug interactions. An additional factor is that olmesartan once-daily regimens are simple and straightforward, which can be an important factor in maintaining adherence to therapy in elderly patients.
Candesartan Candesartan cilexetil is a novel, potent, highly selective non-peptide AT1R blocker, when administered orally it is rapidly and completely hydrolyzed to candesartan and absorbed from the gastrointestinal tract. In patients with aortic valve stenosis, due to direct effects on the myocardium and indirectly through activation of the RAS, pressure overload leads to LV hypertrophy, left atrial dilatation and fibrosis and thus increasing the risk of atrial fibrillation. In these patients, RAS inhibition can reduce mortality and cardiovascular events [11], but candesartan treatment may prevent the new onset of atrial fibrillation [12]. It protects the progression of experimental autoimmune myocarditis to dilated cardiomyopathy in rats via modulation of ACE 2, Ang (1–7) and Mas receptor pathway [3]. In type 2 DM, co-treatment with glucagon like peptide-1, candesartan may promote the survival of β-cells [13]. In selecting candesartan as a therapeutic agent, we could also consider its effect on β-cells survival so that the heart failure patients with DM can benefit with this advantage of candesartan.
Losartan Losartan is the first generation AT1R antagonist, whose clinical effectiveness includes reduction of incidence of cardiac ischemic events in risk populations, including DM patients. It is a pro-drug which is activated in liver with the production of two metabolites one of which blocks AT1R, while the other would be responsible for ancillary features, such as reduction of oxidative stress and reversion of DM-induced mitochondrial dysfunction. In cardiomyocytes from losartan-treated DM rats, KATP current activation, contractile failure and time to rigor show a timing of occurrence similar to those measured in normoglycemic cells, demonstrating that losartan (not compared with other ARBs) counteracts the metabolic remodeling induced by Ang II and by increased oxygen radicals [14]. In addition, it is a partial agonist on the bradykinin receptor B2 (B2R) and which along with the classical mechanism of ARBs, can provide additional cardioprotection (may produce mild cough as adverse effect). In studies performed with mice and a small trial in children with Marfan syndrome (MFS), losartan showed very promising results by reducing the excess protein manufacture by vascular smooth muscle cells of MFS aorta, with almost complete arrest of further aortic root growth [15]. Losartan has a good tolerability, an excellent antihypertensive efficacy and an effective uricosuric and nephroprotective effects; so it can be considered a first choice drug to use in hypertensive and hyperuricemic elderly patients under chemotherapy [16].