Irbesartan

Irbesartan (Avapro) belongs to the class of medicines called angiotensin II inhibitor antihypertensives. It is used to treat high blood pressure(hypertension). Irbesartan works by blocking the action of a substance in the body that causes blood vessels to

Cardioprotective effects of irbesartan in polymicrobial sepsis : The role of the p38MAPK/NF-kappaB signaling pathway.[Pubmed:28144715]

Herz. 2018 Mar;43(2):140-145.

BACKGROUND: Sepsis is a systemic inflammatory response usually correlated with multi-organ failure. Myocardial dysfunction is one of the adverse outcomes in septic patients and results in high mortality rates. The aim of this study was to investigate the impact of Irbesartan in attenuation of cardiac depression during polymicrobial sepsis via decreased activation of the phospho-p38MAPK/nuclear factor (NF)-kappaB signaling pathway. MATERIALS AND METHODS: A model of polymicrobial sepsis induced via cecal ligation and puncture (CLP) with 8- to 12-week-old albino mice was used. Mice were treated with i.p. Irbesartan (3 mg/kg) 1 h before CLP. Using a micro-tipped transducer catheter, the following hemodynamic parameters were evaluated after CLP: heart rate, ejection fraction, left ventricular (LV) end-diastolic pressure, LV systolic pressure, and cardiac output. Plasma levels of proinflammatory cytokines, including tumor necrosis factor (TNF)-alpha, interleukin (IL)-1 beta, IL-6, monocyte chemoattractant protein-1 (MCP-1), and cardiac troponin I (cTn-I), were measured via ELISA analysis. The degree of p38MAPK and NF-kappaB phosphorylation was assessed via Western blotting. RESULTS: Mice treated with Irbesartan displayed improvement in LV function (ejection fraction: 42.4 +/- 1.1% vs. 27.8 +/- 3% in CLP mice). The attenuation of cardiac depression in Irbesartan-treated mice was associated with lower levels of MCP-1 in plasma and a reduction in the levels of TNF-alpha, IL-1beta, and IL-6. Furthermore, Irbesartan-treated mice displayed lower expression levels of p38-MAPK and NF-kappaB phosphorylation. CONCLUSION: Irbesartan can attenuate cardiac dysfunction during polymicrobial sepsis possibly via a reduction of proinflammatory cytokines through decreased activation of the p38MAPK/NF-kappaB pathways.

Exploring the interactions of irbesartan and irbesartan-2-hydroxypropyl-beta-cyclodextrin complex with model membranes.[Pubmed:28274845]

Biochim Biophys Acta Biomembr. 2017 Jun;1859(6):1089-1098.

The interactions of Irbesartan (IRB) and Irbesartan-2-hydroxypropyl-beta-cyclodextrin (HP-beta-CD) complex with dipalmitoyl phosphatidylcholine (DPPC) bilayers have been explored utilizing an array of biophysical techniques ranging from differential scanning calorimetry (DSC), small angle X-ray scattering (SAXS), ESI mass spectrometry (ESI-MS) and solid state nuclear magnetic resonance (ssNMR). Molecular dynamics (MD) calculations have been also conducted to complement the experimental results. Irbesartan was found to be embedded in the lipid membrane core and to affect the phase transition properties of the DPPC bilayers. SAXS studies revealed that Irbesartan alone does not display perfect solvation since some coexisting Irbesartan crystallites are present. In its complexed form IRB gets fully solvated in the membranes showing that encapsulation of IRB in HP-beta-CD may have beneficial effects in the ADME properties of this drug. MD experiments revealed the topological and orientational integration of Irbesartan into the phospholipid bilayer being placed at about 1nm from the membrane centre.

Efficacy of Zofenopril vs. Irbesartan in Combination with a Thiazide Diuretic in Hypertensive Patients with Multiple Risk Factors not Controlled by a Previous Monotherapy: A Review of the Double-Blind, Randomized "Z" Studies.[Pubmed:28260186]

Adv Ther. 2017 Apr;34(4):784-798.

Combinations between an angiotensin converting enzyme (ACE) inhibitor or an angiotensin II receptor blocker (ARB) and hydrochlorothiazide (HCTZ) are among the recommended treatments for hypertensive patients uncontrolled by monotherapy. Four randomized, double-blind, parallel group studies with a similar design, including 1469 hypertensive patients uncontrolled by a previous monotherapy and with >/=1 cardiovascular risk factor, compared the efficacy of a combination of a sulfhydryl ACE inhibitor (zofenopril at 30 or 60 mg) or an ARB (Irbesartan at 150 or 300 mg) plus HCTZ 12.5 mg. The extent of blood pressure (BP)-lowering was assessed in the office and over 24 h. Pleiotropic features of the treatments were evaluated by studying their effect on systemic inflammation, organ damage, arterial stiffness, and metabolic biochemical parameters. Both treatments similarly reduced office and ambulatory BPs after 18-24 weeks. In the ZODIAC study a larger reduction in high sensitivity C reactive protein (hs-CRP) was observed under zofenopril (-0.52 vs. +0.97 mg/dL under Irbesartan, p = 0.001), suggesting a potential protective effect against the development of atherosclerosis. In the ZENITH study the rate of carotid plaque regression was significantly larger under zofenopril (32% vs. 16%; p = 0.047). In the diabetic patients of the ZAMES study, no adverse effects of treatments on blood glucose and lipids as well as an improvement of renal function were observed. In patients with isolated systolic hypertension of the ZEUS study, a slight and similar improvement in renal function and small reductions in pulse wave velocity (PWV), augmentation index (AI), and central systolic BP were documented with both treatments. Thus, the fixed combination of zofenopril and HCTZ may have a relevant place in the treatment of high-risk or monotherapy-treated uncontrolled hypertensive patients requiring a more prompt, intensive, and sustained BP reduction, in line with the recommendations of current guidelines.

Clinical and Echocardiographic Characteristics and Cardiovascular Outcomes According to Diabetes Status in Patients With Heart Failure and Preserved Ejection Fraction: A Report From the I-Preserve Trial (Irbesartan in Heart Failure With Preserved Ejection Fraction).[Pubmed:28052977]

Circulation. 2017 Feb 21;135(8):724-735.

BACKGROUND: In patients with heart failure and preserved ejection fraction, little is known about the characteristics of, and outcomes in, those with and without diabetes mellitus. METHODS: We examined clinical and echocardiographic characteristics and outcomes in the I-Preserve trial (Irbesartan in Heart Failure With Preserved Ejection Fraction) according to history of diabetes mellitus. Cox regression models were used to estimate hazard ratios for cardiovascular outcomes adjusted for known predictors, including age, sex, natriuretic peptides, and comorbidity. Echocardiographic data were available in 745 patients and were additionally adjusted for in supplementary analyses. RESULTS: Overall, 1134 of 4128 patients (27%) had diabetes mellitus. Compared with those without diabetes mellitus, they were more likely to have a history of myocardial infarction (28% versus 22%), higher body mass index (31 versus 29 kg/m(2)), worse Minnesota Living With Heart Failure score (48 versus 40), higher median N-terminal pro-B-type natriuretic peptide concentration (403 versus 320 pg/mL; all P<0.01), more signs of congestion, but no significant difference in left ventricular ejection fraction. Patients with diabetes mellitus had a greater left ventricular mass and left atrial area than patients without diabetes mellitus. Doppler E-wave velocity (86 versus 76 cm/s; P<0.0001) and the E/e' ratio (11.7 versus 10.4; P=0.010) were higher in patients with diabetes mellitus. Over a median follow-up of 4.1 years, cardiovascular death or heart failure hospitalization occurred in 34% of patients with diabetes mellitus versus 22% of those without diabetes mellitus (adjusted hazard ratio, 1.75; 95% confidence interval, 1.49-2.05), and 28% versus 19% of patients with and without diabetes mellitus died (adjusted hazard ratio, 1.59; confidence interval, 1.33-1.91). CONCLUSIONS: In heart failure with preserved ejection fraction, patients with diabetes mellitus have more signs of congestion, worse quality of life, higher N-terminal pro-B-type natriuretic peptide levels, and a poorer prognosis. They also display greater structural and functional echocardiographic abnormalities. Further investigation is needed to determine the mediators of the adverse impact of diabetes mellitus on outcomes in heart failure with preserved ejection fraction and whether they are modifiable. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00095238.