Telmisartan as a metabolic sartan: the first meta-analysis of randomized controlled trials in metabolic syndrome

Identifying Drug Prescription in Newly Diagnosed Hypertension Patients in India

This study evaluated initial antihypertensive drug prescription patterns in Indian healthcare settings. An observational, cross-sectional, prospective prescription registry analyzed prescriptions for 4723 newly diagnosed hypertension patients. Additionally, it investigated the extent to which physicians adhered to either European or Indian hypertension guidelines. Angiotensin receptor blockers (ARBs) were the most commonly prescribed drugs, given to 79% of patients, followed by calcium channel blockers (CCBs) at 55%. Diuretics and beta-blockers (BBs) were prescribed to 27% and 17% of patients, respectively. Monotherapy was administered to 35% of patients, while combination therapies were more prevalent, with dual therapy at 51% and regimens involving three or more drugs prescribed to 14%. Among multi-drug treatments (n = 3082, 65%), 98% received fixed-dose combination tablets. The most common combinations were ARB + CCB (26%), ARB + diuretic (12%), and ARB + CCB + diuretic (8%). Key predictors for an increasing number of prescribed drugs included statin use/dyslipidemia, age, blood pressure level, and diabetes. Non-adherence to hypertension guidelines was evident as 1364 patients classified from moderate to very high risk received monotherapy. Of these, 496 patients had grade 2 or 3 hypertension. Additionally, 88 patients received the undesirable combination of ACEi + ARB, and 267 (15.9%) type 2 diabetes mellitus (T2DM) patients did not receive RAS-blockers (146 on monotherapy). The findings reveal a trend toward utilizing ARBs, CCBs, and combination tablets, indicating improved adherence to guidelines. However, a significant number of patients did not receive appropriate treatment, highlighting areas for improvement in prescription practices.

Chronic kidney disease combined with metabolic syndrome is a non-negligible risk factor

Metabolic syndrome (MetS) is a group of conditions characterized by hypertension (HTN), hyperglycaemia or insulin resistance (IR), hyperlipidaemia, and abdominal obesity. MetS is associated with a high incidence of cardiovascular events and mortality and is an independent risk factor for chronic kidney disease (CKD). MetS can cause CKD or accelerate the progression of kidney disease. Recent studies have found that MetS and kidney disease have a cause-and-effect relationship. Patients with CKD, those undergoing kidney transplantation, or kidney donors have a significantly higher risk of developing MetS than normal people. The present study reviewed the possible mechanisms of MetS in patients with CKD, including the disorders of glucose and fat metabolism after kidney injury, IR, HTN and the administration of glucocorticoid and calcineurin inhibitors. In addition, this study reviewed the effect of MetS in patients with CKD on important target organs such as the kidney, heart, brain and blood vessels, and the treatment and prevention of CKD combined with MetS. The study aims to provide strategies for the diagnosis, treatment and prevention of CKD in patients with MetS.

Effects of telmisartan on metabolic syndrome components: a comprehensive review

Telmisartan is an antagonist of the angiotensin II receptor used in the management of hypertension (alone or in combination with other antihypertensive agents. It belongs to the drug class of angiotensin II receptor blockers (ARBs). Among drugs of this class, telmisartan shows particular pharmacologic properties, including a longer half-life than any other angiotensin II receptor blockers that bring higher and persistent antihypertensive activity. In hypertensive patients, telmisartan has superior efficacy than other antihypertensive drugs (losartan, valsartan, ramipril, atenolol, and perindopril) in controlling blood pressure, especially towards the end of the dosing interval. Telmisartan has a partial PPARγ-agonistic effect whilst does not have the safety concerns of full agonists of PPARγ receptors (thiazolidinediones). Moreover, telmisartan has an agonist activity on PPARα and PPARδ receptors and modulates the adipokine levels. Thus, telmisartan could be considered as a suitable alternative option, with multi-benefit for all components of metabolic syndrome including hypertension, diabetes mellitus, obesity, and hyperlipidemia. This review will highlight the role of telmisartan in metabolic syndrome and the main mechanisms of action of telmisartan are discussed and summarized. Many studies have demonstrated the useful properties of telmisartan in the prevention and improving of metabolic syndrome and this well-tolerated drug can be greatly proposed in the treatment of different components of metabolic syndrome. However, larger and long-duration studies are needed to confirm these findings in long-term observational studies and prospective trials and to determine the optimum dose of telmisartan in metabolic syndrome.

Optimization of blood pressure control in patients with resistant arterial hypertension and visceral obesity

Aim. To evaluate the course of resistant arterial hypertension in patients with visceral obesity, to identify predictors of unsatisfactory shot-term and long-term treatment outcomes, to optimize therapy and improve adherence to treatment. Materials and methods. A total number of 90 individuals with a history of refractory or resistant arterial hypertension and visceral obesity were a subject of intensive study. The prospective analysis group consisted of 30 patients with an individualized management plan each, whereas the retrospective group of real clinical practice included 60 participants. At baseline, all patients were taking antihypertensives like ACE inhibitors or angiotensin II receptor blockers (ARBs)/angiotensin-converting enzyme inhibitors, calcium channel blockers (CCBs), and a diuretic. After the initial examination, therapy was individually optimized for each patient in accordance with current clinical guidelines. Most patients in the retrospective group received ARBs valsartan or losartan, CCBs amlodipine, the diuretics indapamide and torasemide, the -blockers bisoprolol and metoprolol, the 2-agonist moxonidine, and the mineralocorticoid receptor antagonist spironolactone. Patients in the prospective group were prescribed ARBs telmisartan and azilsartan, the CCB lercanidipine, thiazide and thiazide-like diuretics indapamide and chlorthalidone, the -blockers nebivolol and carvedilol, the 1-blocker doxazosin, and spironolactone. A re-examination was performed 2 months later. Subsequently, regular communication was maintained with participants of the prospective group during 8 months using a messenger. Communication with patients of the retrospective group was not maintained. All the patients were then asked to self-report their health status by conducting a telephone survey. Results. After 2 months, according to the data of the follow-up, in the retrospective group the target values of mean daily SBP and DBP were observed in 35 and 36.7% of patients, though the statistics among the patients in the prospective group were 66.7 and 60%, respectively. After 10 months, according to the results of the interviews, the target values of SBP and DBP were observed in 10 and 18.3% of patients, though the statistics among the patients in the prospective group were 93.3 and 96.7%, respectively. In the retrospective group, 78.3% of patients changed the previously selected therapy, in the prospective group this figure was only 20%. In the retrospective group, anthropometric data did not change, while in the prospective group, weight and waist circumference significantly decreased (p0.05). Conclusion. Maintaining regular contact with patients and a well-rounded treatment strategy with individualized choice and dosage of medications with an emphasis on modern metabolically neutral drugs with a prolonged duration of action led to better BP control, increased adherence to therapy and indicated significant weight loss among the patients from the prospective group.

Inflammation Parameters Associated with Metabolic Disorders: Relationship Between Diet and Microbiota

The metabolic syndrome (MetS) includes numerous interrelated clinical, anthropometric, biochemical, and metabolic components and has become a public health problem due to its impact on morbimortality. Inflammation is a central mechanism underlying the etiology and clinical manifestations of MetS, contributing to its related pathological outcomes. Dietary patterns have been associated with the promotion of the diversity of microbiota in the digestive tract. Recently, research has focused on the importance of microbiota changes associated with MetS and inflammation. Other studies have been performed to understand the impact of prebiotics, probiotics, and synbiotics as allies on diet, inflammation, and MetS parameters. This review analyses the correlation between metabolic disorders, inflammation parameters, gut microbiota, and how diet has been involved as treatment of MetS and the modulation of inflammation and microbiota.

Hypertension in Metabolic Syndrome: Novel Insights

BACKGROUND

Metabolic syndrome (MetS) is characterized by the simultaneous presence of obesity, hypertension, dyslipidemia and hyperglycemia in an individual, leading to increased cardiovascular disease (CVD) risk. It affects almost 35% of the US adult population, while its prevalence increases with age. Elevated blood pressure is the most frequent component of the syndrome; however, until now, the optimal antihypertensive regiment has not been defined.

OBJECTIVE

The purpose of this review is to present the proposed definitions for the metabolic syndrome, as well as the prevalence of hypertension in this condition. Moreover, evidence regarding the metabolic properties of the different antihypertensive drug classes and their effect on MetS will be displayed.

METHODS

A comprehensive review of the literature was performed to identify data from clinical studies for the prevalence, pathophysiology and treatment of hypertension in the metabolic syndrome.

RESULTS

Hypertension is present in almost 80% of patients with metabolic syndrome. The use of thiazide diuretics and b-blockers has been discouraged in this population; however, new evidence suggests their use under specific conditions. Calcium channel blockers seem to exert a neutral effect on MetS, while renin-angiotensin system inhibitors are believed to be of the most benefit, although differences exist between the different agents of this category.

CONCLUSION

Controversy still exists regarding the optimal antihypertensive treatment for hypertension in MetS. Due to the high prevalence of hypertension in this population, more data from clinical trials are needed in the future.

Organokines in disease

Studies have linked obesity, metabolic syndrome, type 2 diabetes, cardiovascular disease (CVD), nonalcoholic fatty liver disease (NAFLD) and dementia. Their relationship to the incidence and progression of these disease states suggests an interconnected pathogenesis involving chronic low-grade inflammation and oxidative stress. Metabolic syndrome represents comorbidities of central obesity, insulin resistance, dyslipidemia, hypertension and hyperglycemia associated with increased risk of type 2 diabetes, NAFLD, atherosclerotic CVD and neurodegenerative disease. As the socioeconomic burden for these diseases has grown signficantly with an increasing elderly population, new and alternative pharmacologic solutions for these cardiometabolic diseases are required. Adipose tissue, skeletal muscle and liver are central endocrine organs that regulate inflammation, energy and metabolic homeostasis, and the neuroendocrine axis through synthesis and secretion of adipokines, myokines, and hepatokines, respectively. These organokines affect each other and communicate through various endocrine, paracrine and autocrine pathways. The ultimate goal of this review is to provide a comprehensive understanding of organ crosstalk. This will include the roles of novel organokines in normal physiologic regulation and their pathophysiological effect in obesity, metabolic syndrome, type 2 diabetes, CVD, NAFLD and neurodegenerative disorders.

Beneficial Effects of Adiponectin on Glucose and Lipid Metabolism and Atherosclerotic Progression: Mechanisms and Perspectives

Circulating adiponectin concentrations are reduced in obese individuals, and this reduction has been proposed to have a crucial role in the pathogenesis of atherosclerosis and cardiovascular diseases associated with obesity and the metabolic syndrome. We focus on the effects of adiponectin on glucose and lipid metabolism and on the molecular anti-atherosclerotic properties of adiponectin and also discuss the factors that increase the circulating levels of adiponectin. Adiponectin reduces inflammatory cytokines and oxidative stress, which leads to an improvement of insulin resistance. Adiponectin-induced improvement of insulin resistance and adiponectin itself reduce hepatic glucose production and increase the utilization of glucose and fatty acids by skeletal muscles, lowering blood glucose levels. Adiponectin has also β cell protective effects and may prevent the development of diabetes. Adiponectin concentration has been found to be correlated with lipoprotein metabolism; especially, it is associated with the metabolism of high-density lipoprotein (HDL) and triglyceride (TG). Adiponectin appears to increase HDL and decrease TG. Adiponectin increases ATP-binding cassette transporter A1 and lipoprotein lipase (LPL) and decreases hepatic lipase, which may elevate HDL. Increased LPL mass/activity and very low density lipoprotein (VLDL) receptor and reduced apo-CIII may increase VLDL catabolism and result in the reduction of serum TG. Further, adiponectin has various molecular anti-atherosclerotic properties, such as reduction of scavenger receptors in macrophages and increase of cholesterol efflux. These findings suggest that high levels of circulating adiponectin can protect against atherosclerosis. Weight loss, exercise, nutritional factors, anti-diabetic drugs, lipid-lowering drugs, and anti-hypertensive drugs have been associated with an increase of serum adiponectin level.

Even Short-Term Telmisartan Treatment Ameliorated Insulin Resistance But Had No Influence on Serum Adiponectin and Tumor Necrosis Factor-Alpha Levels in Hypertensive Patients with Metabolic Syndrome

BACKGROUND

We investigated the effect of short-term telmisartan usage in addition to lifestyle changes such as diet and exercise on insulin resistance, lipid metabolism, and serum adiponectin and tumor necrosis factor-alpha (TNF-α) levels in hypertensive patients with metabolic syndrome (MetS).

METHODS

A total of 36 hypertensive patients with MetS were randomized to telmisartan and control groups in an open-labeled prospective study.

RESULTS

There were significant decreases in anthropometric variables of patients according to baseline measurements in both groups at the end of the study. Serum insulin level and insulin resistance assessed by homeostasis model assessment-insulin resistance were decreased significantly in the telmisartan group (P = 0.040 and P = 0.034, respectively) compared with the controls, while there was no statistically significant change in the lipid profiles of the two groups. Serum adiponectin level was increased by 19.1% ± 41.7% in the telmisartan group, but intergroup analysis revealed no significant change. There was also no significant change in serum TNF-α level in either group.

CONCLUSION

It has been observed that even short-term telmisartan treatment had favorable effects on insulin resistance and glucose metabolism compared with lifestyle changes alone. The fundamental effect of telmisartan treatment on insulin resistance renders it a good therapeutic option for hypertensive patients with MetS.

Treatment of hypertension in obese patients: focus on telmisartan

The article discusses the role of telmisartan in the treatment of arterial hypertension in patients with metabolic syndrome. Telmisartan is second-generation type 1 angiotensin II receptor blocker, which has unique pleiotropic effects due to partial affinity for receptors that activate the proliferation of subtype y peroxisomes (PPARy) located in adipose tissue. The interrelation of metaflamation, a specific chronic inflammatory process with pathogenetic mechanisms of development of cardiovascular diseases, including arterial hypertension, is also described in study. The role of the adiponectin peptide is considered, which synthesis is stimulated by partial PPARy receptor agonists (as mentioned above — telmisartan). It has a positive effect on fat and carbohydrate metabolism, as well as cardioprotective properties. The conclusion contains the results of numerous randomized studies and meta-analyzes confirming the high efficacy of telmisartan in the treatment of arterial hypertension in patients with morbid obesity.

Telmisartan reverses antiretroviral-induced adipocyte toxicity and insulin resistance in vitro

BACKGROUND

Antiretroviral therapy in HIV-positive patients leads to insulin resistance which is central to the pathogenesis of various metabolic abnormalities and cardiovascular disease seen in this patient group. We have investigated the dose-response relationship of telmisartan, an antihypertensive, on adipocytes in vitro in order to determine whether it may have metabolic beneficial effects.

METHODS

Using in vitro chronic toxicity models (3T3-F442A murine and primary human adipocytes), we evaluated the effects of different concentrations of telmisartan on adipocyte differentiation and adipogenic gene expression using lipid accumulation assays and real-time polymerase chain reaction, respectively. Adipokine secretion and expression of insulin signalling mediators were evaluated using enzyme-linked immunosorbent assays.

RESULTS

Telmisartan partially reversed the deleterious effects of antiretrovirals on adipocyte lipid accumulation, expression of adipogenic regulators (peroxisome proliferator receptor-gamma and lipin 1), adipokine secretion and expression of the insulin signalling mediator pAkt_Ser473. The metabolic effects of telmisartan followed a non-monotonic response with the maximal effect observed at 5 µM in the primary human adipocyte model.

CONCLUSION

Telmisartan has beneficial metabolic effects in adipocytes in vitro, but its potential to reduce antiretroviral-induced cardiometabolic disease in HIV-infected individuals needs to be evaluated in a well-designed adequately powered clinical trial.

The Different Therapeutic Choices with ARBs. Which One to Give? When? Why?

The renin-angiotensin-aldosterone system plays an important role in the pathophysiology of hypertension and is closely related with cardio- and cerebrovascular events and chronic kidney diseases. Each angiotensin receptor blocker (ARB) is important in the treatment of hypertension, according to the results of recent years. This is a practical review of the available evidence on the different benefits of ARBs beyond their blood pressure-lowering effect, with an emphasis on the differences found between the particular compounds and the therapeutic implications of the findings, with specific reference to the co-morbidities.

Effects of telmisartan on fat distribution: a meta-analysis of randomized controlled trials

OBJECTIVES

Several meta-analyses have confirmed the positive metabolic effects of telmisartan, an angiotensin II receptor blocker that can also act as a partial peroxisome proliferator-activated receptor-γ agonist, compared to those of other angiotensin II receptor blockers. These effects include decreased fasting glucose, glycosylated hemoglobin, interleukin-6, and tumor necrosis factor-α levels. However, no systemic analysis of telmisartan's effects on body fat distribution has been performed. We performed a meta-analysis of randomized controlled telmisartan trials to investigate its effects on body weight, fat distribution, and visceral adipose reduction.

RESEARCH DESIGN AND METHODS

A literature search was performed using Embase, MEDLINE, and the Cochrane Library between January 1966 and November 2013. Randomized controlled trials in English and meeting the following criterion were included: random assignment of hypertensive participants with overweight/obesity, metabolic syndrome, or glucose intolerance to telmisartan or control therapy group.

RESULTS

Of 651 potentially relevant reports, 15 satisfied the inclusion criterion. While visceral fat area was significantly lower in the telmisartan group than in the control group (weighted mean difference = -18.13 cm(2), 95% C.I. = -27.16 to -9.11, Pχ(2) = 0.19, I(2) = 41%), subcutaneous fat area was similar (weighted mean difference =2.94 cm(2), 95% C.I. = -13.01 to 18.89, Pχ(2) = 0.30, I(2) = 17%). Total cholesterol levels were significantly different between the groups (standardized mean difference = -0.24, 95% C.I. = -0.45 to -0.03, Pχ(2) = 0.0002, I(2) = 67%).

LIMITATIONS

Limitations include: (1) limited number of studies, especially those evaluating fat distribution; (2) different imaging modalities to assess visceral fat area (V.F.A.) and subcutaneous fat area (S.F.A.); (3) observed heterogeneity.

CONCLUSION

The findings suggest that telmisartan affected fat distribution, inducing visceral fat reduction, and thus could be useful in hypertensive patients with obesity/overweight, metabolic syndrome, or glucose intolerance.

Targeting inflammation in metabolic syndrome

The metabolic syndrome (MetS) is comprised of a cluster of closely related risk factors, including visceral adiposity, insulin resistance, hypertension, high triglyceride, and low high-density lipoprotein cholesterol; all of which increase the risk for the development of type 2 diabetes and cardiovascular disease. A chronic state of inflammation appears to be a central mechanism underlying the pathophysiology of insulin resistance and MetS. In this review, we summarize recent research which has provided insight into the mechanisms by which inflammation underlies the pathophysiology of the individual components of MetS including visceral adiposity, hyperglycemia and insulin resistance, dyslipidemia, and hypertension. On the basis of these mechanisms, we summarize therapeutic modalities to target inflammation in the MetS and its individual components. Current therapeutic modalities can modulate the individual components of MetS and have a direct anti-inflammatory effect. Lifestyle modifications including exercise, weight loss, and diets high in fruits, vegetables, fiber, whole grains, and low-fat dairy and low in saturated fat and glucose are recommended as a first line therapy. The Mediterranean and dietary approaches to stop hypertension diets are especially beneficial and have been shown to prevent development of MetS. Moreover, the Mediterranean diet has been associated with reductions in total and cardiovascular mortality. Omega-3 fatty acids and peroxisome proliferator-activated receptor α agonists lower high levels of triglyceride; their role in targeting inflammation is reviewed. Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and aldosterone blockers comprise pharmacologic therapies for hypertension but also target other aspects of MetS including inflammation. Statin drugs target many of the underlying inflammatory pathways involved in MetS.

Phase 4 Studies in Heart Failure - What is Done and What is Needed?

Congestive heart failure (CHF) therapeutics is generated through a well-described evidence generating process. Phases 1 - 3 of this process are required prior to approval and widespread clinical use. Phase 3 in almost all cases is a methodologically sound randomized controlled trial (RCT). After this phase it is generally accepted that the treatment has a significant, independent and prognostically beneficial effect on the pathophysiological process. A major criticism of RCTs is the population to whom the result is applicable. When this population is significantly different from the trial cohort the external validity comes into question. Should the continuation of the evidence generating process continue these problems might be identified. Post marketing surveillance through phase 4 and comparative effectiveness studies through phase 5 trials are often underperformed in comparison to the RCT. These processes can help identify remote adverse events and define new hypotheses for community level benefits. This review is aimed at exploring the post-marketing scene for CHF therapeutics from an Australian health system perspective. We explore the phases of clinical trials, the level of evidence currently available and options for ensuring greater accountability for community level CHF clinical outcomes.

Metabolic syndrome update

The metabolic syndrome is a multiplex risk factor for atherosclerotic cardiovascular disease and type 2 diabetes. It is composed of atherogenic dyslipidemia, elevated blood pressure, insulin resistance and elevated glucose, a pro-thrombotic state, and a pro-inflammatory state. Excess energy intake and concomitant obesity are the major drivers of the syndrome. Lifestyle intervention can reverse metabolic risk factors, but at times, drug therapies or bariatric surgery may be required to control more overt risk factors.

Enhanced pan-peroxisome proliferator-activated receptor gene and protein expression in adipose tissue of diet-induced obese mice treated with telmisartan

Telmisartan has previously been used to target obesity, showing peroxisome proliferator-activated receptor (PPAR) β/δ-related effects in white adipose tissue (WAT). We sought to evaluate whether telmisartan enhances gene and protein expression of all PPAR isoforms in WAT and brown adipose tissue (BAT), as well as their downstream effects upon insulin resistance, adipokine profile and adaptive thermogenesis. Male C57BL/6 mice were fed standard chow (SC; 10% lipids) or high-fat diet (HF; 50% lipids) for 10 weeks. Animals were then randomly allocated into the following four groups: SC, SC-T, HF and HF-T. Telmisartan [10 mg (kg diet)(-1)] was administered for 4 weeks in the diet. Animals in the HF group were overweight and exhibited hypertension, insulin resistance, decreased energy expenditure, a pro-inflammatory adipokine profile and abnormal fat pad mass distribution. Animals in the HF group showed decreased expression of PPARα, β/δ and γ in WAT and BAT, resulting in impaired glucose uptake and insufficient thermogenesis. Due to the improvement in the adipokine profile and enhanced insulin sensitivity with adequate insulin-stimulated glucose uptake after treatment with telmisartan, the activation of all PPAR isoforms in WAT was beneficial. In BAT, telmisartan induced sustained sympathetic activation, because the β3-adrenergic receptor was induced by PPARβ/δ, while uncoupling protein 1 was induced by PPARα to promote thermogenesis. Telmisartan exerted anti-obesity effects through higher pan-PPAR gene and protein expression. Upon PPARα, β/δ and γ (pan-PPAR) agonism in adipose tissue of obese mice, telmisartan ameliorates inflammation and insulin resistance, as well as inducing non-shivering thermogenesis. Our results point to new therapeutic targets for the control of obesity and comorbidities through pan-PPAR-related effects.

Distinct properties of telmisartan on agonistic activities for peroxisome proliferator-activated receptor γ among clinically used angiotensin II receptor blockers: drug-target interaction analyses

A proportion of angiotensin II type 1 receptor blockers (ARBs) improves glucose dyshomeostasis and insulin resistance in a clinical setting. Of these ARBs, telmisartan has the unique property of being a partial agonist for peroxisome proliferator-activated receptor γ (PPARγ). However, the detailed mechanism of how telmisartan acts on PPARγ and exerts its insulin-sensitizing effect is poorly understood. In this context, we investigated the agonistic activity of a variety of clinically available ARBs on PPARγ using isothermal titration calorimetry (ITC) and surface plasmon resonance (SPR) system. Based on physicochemical data, we then reevaluated the metabolically beneficial effects of telmisartan in cultured murine adipocytes. ITC and SPR assays demonstrated that telmisartan exhibited the highest affinity of the ARBs tested. Distribution coefficient and parallel artificial membrane permeability assays were used to assess lipophilicity and cell permeability, for which telmisartan exhibited the highest levels of both. We next examined the effect of each ARB on insulin-mediated glucose metabolism in 3T3-L1 preadipocytes. To investigate the impact on adipogenesis, 3T3-L1 preadipocytes were differentiated with each ARB in addition to standard inducers of differentiation for adipogenesis. Telmisartan dose-dependently facilitated adipogenesis and markedly augmented the mRNA expression of adipocyte fatty acid-binding protein (aP2), accompanied by an increase in the uptake of 2-deoxyglucose and protein expression of glucose transporter 4 (GLUT4). In contrast, other ARBs showed only marginal effects in these experiments. In accordance with its highest affinity of binding for PPARγ as well as the highest cell permeability, telmisartan superbly activates PPARγ among the ARBs tested, thereby providing a fresh avenue for treating hypertensive patients with metabolic derangement.

Protective effect of telmisartan against oxidative damage induced by high glucose in neuronal PC12 cell

Telmisartan is an angiotensin II type 1 receptor blocker and partial agonist of peroxisome proliferator-activated receptor gamma (PPAR-γ). Here, we investigated the protective capacity of telmisartan against high glucose (HG)-elicited oxidative damage in PC12 cells. The activity of lactate dehydrogenase (LDH), NADPH oxidase (NOX), superoxide dismutase (SOD), catalase (CAT) as well as the levels of malondialdehyde (MDA), glutathione (GSH), intracellular reactive oxygen species (ROS), cell viability and DNA fragmentation were measured in HG-treated PC12 cells with and without telmisartan co-treatment. Moreover, the direct antioxidant effect of telmisartan was determined by 2,2-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assay and protein expression of Bax, Bcl-2, cleaved caspase-3 and NOX subunit p47phox by western blotting. Telmisartan exhibited antioxidant activity in the ABTS assay with the IC50 value of 37.5 μM. Pretreatment of PC12 cells with telmisartan, prior to HG exposure, was associated with a marked diminution in cleaved caspase-3 expression, DNA fragmentation, Bax/Bcl-2 ratio, intracellular ROS and MDA levels. Additionally, the cell viability, GSH level, SOD and CAT activity were notably elevated by telmisartan, whereas the activity and the protein expression of NADPH oxidase subunit p47phox were attenuated. Interestingly, co-treatment with GW9662, a PPAR-γ antagonist, partially inhibited the beneficial effects of telmisartan. These findings suggest that telmisartan has protective effects on HG-induced neurotoxicity in PC12 cells, which may be related to its antioxidant action and inhibition of NADPH oxidase. Furthermore, the results show that PPAR-γ activation is involved in the neuroprotective effects of telmisartan.