Effect of pioglitazone on left ventricular diastolic function and fibrosis of type III collagen in type 2 diabetic patients

Change in left ventricular diastolic function after pioglitazone treatment in patients with type 2 diabetes mellitus: A protocol for systematic review and meta-analysis

BACKGROUND

Pioglitazone is currently used as an anti-diabetic agent and can reduce cardiovascular events in in patients with type 2 diabetes mellitus (T2DM). Left ventricular diastolic dysfunction has been recognized as an early manifestation of myocardial dysfunction in T2DM patients. This systematic review and meta-analysis aimed to investigate changes in the left ventricular diastolic function after the treatment of pioglitazone.

METHODS

A systematic literature search of PubMed, Embase, and the Cochrane Library until May 2021 with keywords pioglitazone and left ventricular diastolic function was performed in accordance with the meta-analysis of observational studies in epidemiology guidelines and preferred reporting items for systematic reviews and meta-analyses statement. Three reviewers independently selected the studies and extracted data. Quality assessment of the included studies was undergone. A fixed effects model was used to calculate overall effect sizes. Subgroup analyses were subsequently performed. A fixed effects model was used to calculate the overall effect size. Subgroup analyses were then performed.

RESULTS

Seven studies with 233 patients were investigated. We found pioglitazone significantly improved hemoglobin A1c (%) in patients with T2DM and left ventricular diastolic function had an improvement tendency (weighted mean difference [WMD], 0.03; 95% confidence interval [CI], 0.01-0.05, P < .01) despite moderate heterogeneity (I2 = 66%). Subsequent subgroup analysis indicated that left ventricular diastolic function were significantly improved (WMD, 0.20; 95% CI, 0.12-0.29, P < .001) in T2DM patients whose average age < 55 after receiving pioglitazone treatment. However, in T2DM patients with mean age ≥ 55 years, there was no significant improvement of left ventricular diastolic function (WMD, 0.02; 95% CI, 0-0.04, P = .04).

CONCLUSION

Pioglitazone treatment significantly improved left ventricular diastolic function in type 2 diabetic patients with a mean age of < 55 years, but did not improve left ventricular diastolic function in patients with a mean age of ≥ 55 years.

Rethinking pioglitazone as a cardioprotective agent: a new perspective on an overlooked drug

Since 1985, the thiazolidinedione pioglitazone has been widely used as an insulin sensitizer drug for type 2 diabetes mellitus (T2DM). Although fluid retention was early recognized as a safety concern, data from clinical trials have not provided conclusive evidence for a benefit or a harm on cardiac function, leaving the question unanswered. We reviewed the available evidence encompassing both in vitro and in vivo studies in tissues, isolated organs, animals and humans, including the evidence generated by major clinical trials. Despite the increased risk of hospitalization for heart failure due to fluid retention, pioglitazone is consistently associated with reduced risk of myocardial infarction and ischemic stroke both in primary and secondary prevention, without any proven direct harm on the myocardium. Moreover, it reduces atherosclerosis progression, in-stent restenosis after coronary stent implantation, progression rate from persistent to permanent atrial fibrillation, and reablation rate in diabetic patients with paroxysmal atrial fibrillation after catheter ablation. In fact, human and animal studies consistently report direct beneficial effects on cardiomyocytes electrophysiology, energetic metabolism, ischemia–reperfusion injury, cardiac remodeling, neurohormonal activation, pulmonary circulation and biventricular systo-diastolic functions. The mechanisms involved may rely either on anti-remodeling properties (endothelium protective, inflammation-modulating, anti-proliferative and anti-fibrotic properties) and/or on metabolic (adipose tissue metabolism, increased HDL cholesterol) and neurohormonal (renin–angiotensin–aldosterone system, sympathetic nervous system, and adiponectin) modulation of the cardiovascular system. With appropriate prescription and titration, pioglitazone remains a useful tool in the arsenal of the clinical diabetologist.

Nanomedicine for the treatment of diabetes-associated cardiovascular diseases and fibrosis

Cardiomyopathy and fibrosis are the main causes of heart failure in diabetes patients. For therapeutic purposes, a delivery system is required to enhance antidiabetic drug efficacy and specifically target profibrotic pathways in cardiomyocytes. Nanoparticles (NPs) have distinct advantages, including biocompatibility, bioavailability, targeting efficiency, and minimal toxicity, which make them ideal for antidiabetic treatment. In this review, we overview the latest information on the pathogenesis of cardiomyopathy and fibrosis in diabetes patients. We summarize how NP applications improve insulin and liraglutide efficacy and their sustained release upon oral administration. We provide a comprehensive review of the results of NP clinical trials in diabetes patients and of animal studies investigating the effects of NP-mediated anti-fibrotic treatments. Collectively, the application of advanced NP delivery systems in the treatment of cardiomyopathy and fibrosis in diabetes patients is a promising and innovative therapeutic strategy.

Pioglitazone: The forgotten, cost-effective cardioprotective drug for type 2 diabetes

Type 2 diabetes individuals are at high risk for macrovascular complications: myocardial infarction, stroke and cardiovascular mortality. Recent cardiovascular outcome trials have demonstrated that agents in two antidiabetic classes (SGLT2 inhibitors and GLP-1 receptor agonists) reduce major adverse cardiovascular events. However, there is strong evidence that an older and now generically available medication, the thiazolidinedione, pioglitazone, can retard the atherosclerotic process (PERISCOPE and Chicago) and reduce cardiovascular events in large randomized prospective cardiovascular outcome trials (IRIS and PROactive). Pioglitazone is a potent insulin sensitizer, preserves beta-cell function, causes durable reduction in HbA1c, corrects multiple components of metabolic syndrome and improves nonalcoholic fatty liver disease/nonalcoholic steatohepatitis. Adverse effects (weight gain, fluid retention, fractures) must be considered, but are diminished with lower doses and are arguably outweighed by these multiple benefits. With healthcare expenses attributable to diabetes increasing rapidly, this cost-effective drug requires reconsideration in the therapeutic armamentarium for the disease.

Effect of pioglitazone on cardiometabolic profiles and safety in patients with type 2 diabetes undergoing percutaneous coronary artery intervention: a prospective, multicenter, randomized trial

Pioglitazone has superior antiatherosclerotic effects compared with other classes of antidiabetic agents, and there is substantial evidence that pioglitazone improves cardiovascular (CV) outcomes. However, there is also a potential risk of worsening heart failure (HF). Therefore, it is clinically important to determine whether pioglitazone is safe in patients with type 2 diabetes mellitus (T2DM) who require treatment for secondary prevention of CV disease, since they have an intrinsically higher risk of HF. This prospective, multicenter, open-label, randomized study investigated the effects of pioglitazone on cardiometabolic profiles and CV safety in T2DM patients undergoing elective percutaneous coronary intervention (PCI) using bare-metal stents or first-generation drug-eluting stents. A total of 94 eligible patients were randomly assigned to either a pioglitazone or conventional (control) group, and pioglitazone was started the day before PCI. Cardiometabolic profiles were evaluated before PCI and at primary follow-up coronary angiography (5-8 months). Pioglitazone treatment reduced HbA1c levels to a similar degree as conventional treatment (pioglitazone group 6.5 to 6.0%, P < 0.01; control group 6.5 to 5.9%, P < 0.001), without body weight gain. Levels of high-molecular weight adiponectin increased more in the pioglitazone group than the control group (P < 0.001), and the changes were irrespective of baseline glycemic control. Furthermore, pioglitazone significantly reduced plasma levels of natriuretic peptides and preserved cardiac systolic and diastolic function (assessed by echocardiography) without incident hospitalization for worsening HF. The incidence of clinical adverse events was also comparable between the groups. These results indicate that pioglitazone treatment before and after elective PCI may be tolerable and clinically safe and may improve cardiometabolic profiles in T2DM patients.

Activation of Peroxisome Proliferator-activated Receptor γ Prevents Development of Heart Failure With Preserved Ejection Fraction; Inhibition of Wnt-β-catenin Signaling as a Possible Mechanism

Left ventricular (LV) fibrosis plays an important role in the development of heart failure with preserved ejection fraction (HFpEF). We investigated whether chronic peroxisome proliferator-activated receptor gamma agonism with pioglitazone can prevent the development of HFpEF. We also evaluated the role of Wnt-β-catenin signaling in the development of HFpEF, and its relationship to peroxisome proliferator-activated receptor gamma signaling. Dahl salt-sensitive rats placed on an 8% NaCl diet from age 6 weeks were used as HFpEF model. Rats placed on 0.3% NaCl diet served as controls (n = 7). HFpEF model rats were randomized to no treatment (n = 7) or treatment with pioglitazone (2.5 mg/kg per day, n = 7) at age 13 weeks. Pioglitazone administration from age 13 to 21 weeks attenuated the development of LV fibrosis and stiffening (both P < 0.05), and subsequently prevented the development of HFpEF. In the untreated HFpEF model, Wnt1, 2, 10b messenger RNA and β-catenin protein expression levels in the left ventricle increased in the heart failure stage, along with the increase in type I collagen messenger RNA expression levels. Administration of pioglitazone attenuated the activation of Wnt-β-catenin signaling. Our results show that pioglitazone prevented the development of LV fibrosis and HFpEF in a rat model, at least partly due to attenuated Wnt-β-catenin signaling.

Pioglitazone and the secondary prevention of cardiovascular disease. A meta-analysis of randomized-controlled trials

Background and aims

Pioglitazone targets multiple pathogenic pathways involved in the development of cardiovascular diseases (CVD). The aim of this systematic review and meta-analysis is to assess the effects of pioglitazone treatment on the secondary prevention of CVD.

Methods

Randomized-controlled trials of pioglitazone in patients with CVD were identified through PubMed, Embase, Cochrane and CINAHL, in a search up to May 2016. Studies were included if pioglitazone was compared with any control (usual care, placebo or active comparator) and if patients were previously diagnosed with CVD. The outcomes of interest included major adverse cardiovascular events (MACE), myocardial infarction (MI), stroke, all-cause mortality and heart failure (HF). All outcomes were compared by pooled risk ratios (RR) with a 95% confidence interval (CI). Pooled estimates were calculated using a random-effects model.

Results

Ten studies reported the effects of pioglitazone on any of the outcomes of interest. Pioglitazone reduced recurrent MACE (RR 0.74, 95% 0.60–0.92; I² = 35), MI (RR 0.77, 95% CI 0.64–0.93; I² = 0%), or stroke (RR 0.81, 95% CI 0.68–0.96; I² = 0%). Pioglitazone did not reduce all-cause mortality (RR 0.94, 95% CI 0.81–1.08; I² = 0%), whereas pioglitazone treatment was associated with an increased risk of HF (RR 1.33, 95% CI 1.14–1.54).

Conclusions

Pioglitazone lowers the risk of recurrent MACE, stroke, or MI in patients with clinical manifest vascular disease. Pioglitazone does not lower the risk for all-cause mortality, and increases the risk for the development of HF.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-017-0617-4) contains supplementary material, which is available to authorized users.

Procollagen type III amino terminal peptide and myocardial fibrosis: A study in hypertensive patients with and without left ventricular hypertrophy

INTRODUCTION AND OBJECTIVES

An exaggerated accumulation of type I and type III fibrillar collagens occurs throughout the free wall and interventricular septum of patients with primary hypertension and left ventricular hypertrophy (LVH). In the present study the serum concentration of procollagen type III amino terminal peptide (PIIIP) was measured to determine the value of this peptide as a potential marker of ventricular fibrosis in hypertensive patients, particularly those with LVH.

METHODS

The study population consisted of patients with never-treated mild to moderate essential hypertension and 30 normotensive control subjects. Clinical, echocardiographic, electrocardiographic and biochemical parameters were assessed in all patients.

RESULTS

Heart rate, body mass index and levels of blood pressure were increased in hypertensives, particularly those with LVH, compared to normotensive controls. Posterior wall thickness, left ventricular (LV) mass and LV mass index, and serum PIIIP concentration were also increased in hypertensives, with significant differences between the two hypertensive groups. The ratio between maximal early and late transmitral flow velocity measured during diastole was lower in hypertensives, particularly those with LVH, than in normotensive controls.

CONCLUSIONS

The increase in PIIIP indicates that type III collagen synthesis increases in hypertensives, particularly those with LVH, implying that alterations in the heart in hypertension are the result not solely of hypertrophied LV muscle, but also of increased collagen deposition within the ventricular wall and around the coronary vessels. Thus, measurement of serum PIIIP could be a practical and useful tool in the non-invasive assessment of myocardial remodeling in hypertension.

Ibuprofen attenuates cardiac fibrosis in streptozotocin-induced diabetic rats

OBJECTIVE

To investigate the effects of ibuprofen on cardiac fibrosis in a rat model of type 1 diabetes.

METHODS

The diabetic model was established by injecting streptozotocin into the rats. Then, ibuprofen or pioglitazone was given by gavage for 8 weeks. The cardiac fibrosis was assessed, and the major components of the renin-angiotensin system, the transforming growth factor β1 (TGF-β1) and the mammalian target of rapamycin (mTOR), were evaluated by histopathological, immunohistochemical, Western blot analysis or ELISA assay.

RESULTS

Obvious cardiac fibrosis was detected in the diabetic group and was alleviated by ibuprofen treatment. Angiotensin-converting enzyme (ACE), angiotensin (Ang) II and AngII type 1 receptor (AT1-R) levels were higher, and ACE2, Ang(1-7) and Mas receptor (Mas-R) were lower in the diabetic group. The ratio of ACE to ACE2 was raised in the diabetic group. All these changes were ameliorated by ibuprofen. TGF-β1 and mTOR were raised in the hearts of the diabetic group and were attenuated by ibuprofen treatment. There was no significant difference between the ibuprofen and the pioglitazone groups.

CONCLUSION

Ibuprofen could ameliorate the cardiac fibrosis in diabetic rats by reduction of the ACE/AngII/AT1-R axis and enhancement of the ACE2/Ang(1-7)/Mas-R axis, leading to a decrease in TGF-β1 and mTOR.

Connexin 43, angiotensin II, endothelin 1, and type III collagen alterations in heart of rats having undergone fatal electrocution

Death due to accidental electrocution occurs frequently. The aim of this study was to investigate alterations in cardiac connexin 43 (Cx43), angiotensin II (Ang II), endothelin 1 (ET-1), and type III collagen associated with fatal electrocution.Twenty-four Sprague-Dawley rats were divided into control, fatal electrocution (220 V, 50 Hz, 60 seconds), and electrical injury (220 V, 50 Hz, 60 seconds) groups. Animals were deeply anesthetized with sodium pentobarbital before each treatment, with the anode connected to the left foreleg and the cathode to the right hindleg, followed by cervical dislocation. Control animals received cervical dislocation alone. Immunohistochemical analysis was performed to evaluate the cardiac protein expression of Cx43, Ang II, ET-1, and type III collagen. Sections were analyzed by digital image analysis.The expression of Cx43 was significantly reduced after fatal electrocution, with the integrated optical density also lower when compared with control (P < 0.05). Expression of both Ang II and ET-1 was significantly increased after fatal electrocution, supported by integrated optical density when compared with control (P < 0.05). But no significant difference was found in type III collagen expression between the fatal electrocution group and the control group.In summary, cardiac protein expression of Cx43, Ang II, and ET-1 was found to be significantly altered with fatal electrocution, suggesting that these 3 proteins may be important underlying mechanisms of death during fatal electrocution. The current findings indicate that such alterations would be reflected in abnormal cardiac function and a possible cause of sudden death.

Lack of effects of pioglitazone on cardiac function in patients with type 2 diabetes and evidence of left ventricular diastolic dysfunction: a tissue doppler imaging study

Background

Thiazolidinediones, used for the treatment of patients with type 2 diabetes mellitus (DM2), are associated with an increased incidence of heart failure. We sought to investigate the effects of pioglitazone on novel echocardiographic indices of left ventricular (LV) diastolic function in DM2 patients with LV diastolic dysfunction (LVDD).

Methods

Eighty-eight asymptomatic DM2 patients on metformin and/or sulfonylureas, aged 64.5 ± 7.7 years, without known cardiovascular disease, with normal LV systolic function and evidence of LVDD were randomly assigned to pioglitazone 30 mg/day (n = 42) or an increase in dose of other oral agents (n = 39) for 6 months. All patients underwent transthoracic conventional and Tissue Doppler Imaging echocardiography at baseline and follow-up. The primary end-point was change in early diastolic velocity of the mitral annulus (E').

Results

Improvement of glycaemic control was similar in the 2 groups. A significant difference (p < 0.05) between the 2 groups was found in the treatment-induced changes in fasting insulin, the insulin resistance index HOMA, HDL cholesterol, triglycerides, diastolic blood pressure (all in favor of pioglitazone) and in body weight (increase with pioglitazone). No significant changes were observed in any echocardiographic parameter in either group and did not differ between groups (p = NS for all). E' increased non-significantly and to a similar extent in both groups (p = NS).

Conclusions

In asymptomatic DM2 patients with LVDD, the addition of pioglitazone to oral conventional treatment for 6 months does not induce any adverse or favorable changes in LV diastolic or systolic function despite improvements in glycaemic control, insulin sensitivity, lipid profile, and blood pressure.