Lipotoxicity as a therapeutic target in the type 2 diabetic heart.

Cardiac lipotoxicity, characterized by excessive lipid accumulation in the cardiac tissue, is a critical contributor to the pathogenesis of diabetic heart. Recent research has highlighted the key mechanisms underlying lipotoxicity, including mitochondrial dysfunction, endoplasmic reticulum stress, inflammation, and cell apoptosis, which ultimately impair the cardiac function. Various therapeutic interventions have been developed to target these pathways, mitigate lipotoxicity, and improve cardiovascular outcomes in diabetic patients.

New Insights into IGF-1 Signaling in the Heart.

Insulin-like growth factor-1 (IGF-1) signaling has multiple physiological roles in cellular growth, metabolism, and aging. Myocardial hypertrophy, cell death, senescence, fibrosis, and electrical remodeling are hallmarks of various heart diseases and contribute to the progression of heart failure. This review highlights the critical role of IGF-1 and its cognate receptor in cardiac hypertrophy, aging, and remodeling.

Insulin signaling is critical for sinoatrial node maintenance and function.

Insulin and insulin-like growth factor 1 (IGF-1) signaling regulate cellular growth and glucose metabolism in the myocardium. However, their physiological role in the cells of the cardiac conduction system has never been explored. Therefore, we sought to determine the spatiotemporal function of insulin/IGF-1 receptors in the sinoatrial node (SAN).

The Impact of Fine Particulate Matter 2.5 on the Cardiovascular System: A Review of the Invisible Killer.

Air pollution exerts several deleterious effects on the cardiovascular system, with cardiovascular disease (CVD) accounting for 80% of all premature deaths caused by air pollution. Short-term exposure to particulate matter 2.5 (PM) leads to acute CVD-associated deaths and nonfatal events, whereas long-term exposure increases CVD-associated risk of death and reduces longevity.

Roles of NAD(P)H:quinone Oxidoreductase 1 in Diverse Diseases.

NAD(P)H:quinone oxidoreductase (NQO) is an antioxidant flavoprotein that catalyzes the reduction of highly reactive quinone metabolites by employing NAD(P)H as an electron donor. There are two NQO enzymes-NQO1 and NQO2-in mammalian systems. In particular, NQO1 exerts many biological activities, including antioxidant activities, anti-inflammatory effects, and interactions with tumor suppressors.

IGF-1 protects against angiotensin II-induced cardiac fibrosis by targeting αSMA.

The insulin-like growth factor 1 receptor (IGF-1R) signaling in cardiomyocytes is implicated in physiological hypertrophy and myocardial aging. Although fibroblasts account for a small amount of the heart, they are activated when the heart is damaged to promote cardiac remodeling. However, the role of IGF-1R signaling in cardiac fibroblasts is still unknown.

Application of Animal Models in Diabetic Cardiomyopathy.

Diabetic heart disease is a growing and important public health risk. Apart from the risk of coronary artery disease or hypertension, diabetes mellitus (DM) is a well-known risk factor for heart failure in the form of diabetic cardiomyopathy (DiaCM). Currently, DiaCM is defined as myocardial dysfunction in patients with DM in the absence of coronary artery disease and hypertension.

Characterization of Circular RNAs in Vascular Smooth Muscle Cells with Vascular Calcification.

Circular RNAs (circRNAs) are generally formed by back splicing and are expressed in various cells. Vascular calcification (VC), a common complication of chronic kidney disease (CKD), is often associated with cardiovascular disease. The relationship between circRNAs and VC has not yet been studied.

Therapeutic strategy for atherosclerosis based on bone-vascular axis hypothesis.

As the world's older population grows, the disease burden of atherosclerosis is rapidly increasing, causing significant morbidity and mortality worldwide. Despite recent improvements in the control of vascular risk factors, a significant number of patients still suffer from vascular events and the progression of atherosclerosis. Aging also results in decreased bone mineral density.

RANKL blockade suppresses pathological angiogenesis and vascular leakage in ischemic retinopathy.

Receptor activator of NF-κB ligand (RANKL) is a member of the TNF superfamily. RANKL increases endothelial permeability and induces angiogenesis, suggesting its critical roles in the vasculature. Despite the evidence implicating RANKL in vascular pathology, its role in ischemic retinopathy has not been previously reported.

Long noncoding RNAs in vascular smooth muscle cells regulate vascular calcification.

Vascular calcification is characterized by the accumulation of hydroxyapatite crystals, which is a result of aberrant mineral metabolism. Although many clinical studies have reported its adverse effects on cardiovascular morbidity, the molecular mechanism of vascular calcification, especially the involvement of long noncoding RNAs (lncRNAs), is not yet reported. From the transcriptomic analysis, we discovered hundreds of lncRNAs differentially expressed in rat vascular smooth muscle cells (VSMCs) treated with inorganic phosphate, which mimics vascular calcification.

Inhibition of heat shock protein 70 blocks the development of cardiac hypertrophy by modulating the phosphorylation of histone deacetylase 2.

Aims: Previously, we reported that phosphorylation of histone deacetylase 2 (HDAC2) and the resulting activation causes cardiac hypertrophy. Through further study of the specific binding partners of phosphorylated HDAC2 and their mechanism of regulation, we can better understand how cardiac hypertrophy develops. Thus, in the present study, we aimed to elucidate the function of one such binding partner, heat shock protein 70 (HSP70).

Thyrocyte-specific deletion of insulin and IGF-1 receptors induces papillary thyroid carcinoma-like lesions through EGFR pathway activation.

Insulin and insulin-like growth factor (IGF)-1 signaling in the thyroid are thought to be permissive for the coordinated regulation by thyroid-stimulating hormone (TSH) of thyrocyte proliferation and hormone production. However, the integrated role of insulin receptor (IR) and IGF-1 receptor (IGF-1R) in thyroid development and function has not been explored. Here, we generated thyrocyte-specific IR and IGF-1R double knockout (DTIRKO) mice to precisely evaluate the coordinated functions of these receptors in the thyroid of neonates and adults.

Comparison of Adherence to Glimepiride/Metformin Sustained Release Once-daily Versus Glimepiride/Metformin Immediate Release BID Fixed-combination Therapy Using the Medication Event Monitoring System in Patients With Type 2 Diabetes.

Purpose: The purpose of this study was to compare the adherence of the glimepiride/metformin sustained release (GM-SR) once-daily fixed-dose combination and glimepiride/metformin immediate release (GM-IR) BID fixed-dose combination in type 2 diabetes therapies.

Methods: An open-label, randomized, multicenter, parallel-group study was conducted at 11 hospitals in the Republic of Korea. A total of 168 patients with type 2 diabetes treated with >4 mg of glimepiride and 1000 mg of metformin by using free or fixed-dose combination therapy for at least 2 weeks were enrolled.

Identification of long noncoding RNAs involved in muscle differentiation.

Long noncoding RNAs (lncRNAs) are a large class of regulatory RNAs with diverse roles in cellular processes. Thousands of lncRNAs have been discovered; however, their roles in the regulation of muscle differentiation are unclear because no comprehensive analysis of lncRNAs during this process has been performed. In the present study, by combining diverse RNA sequencing datasets obtained from public database, we discovered lncRNAs that could behave as regulators in the differentiation of smooth or skeletal muscle cells.

Impact of diabetes mellitus and chronic liver disease on the incidence of dementia and all-cause mortality among patients with dementia.

This study investigated the effects of the presence of type 2 diabetes mellitus (T2D) and/or chronic liver disease (CLD) on the incidence and prognosis of dementia during a 10-year period in Korea using a nationwide population-based dataset from the Korea National Health Insurance Service.To assess the impact of T2D and CLD on the incidence of dementia, we included subjects aged ≥60 years without dementia, T2D, and CLD from 2003 to 2005. We created another cohort for evaluating the all-cause mortality in subjects with dementia between 2003 and 2005.

Connexin43 and zonula occludens-1 are targets of Akt in cardiomyocytes that correlate with cardiac contractile dysfunction in Akt deficient hearts.

While deletion of Akt1 results in a smaller heart size and Akt2 mice are mildly insulin resistant, Akt1/Akt2 mice exhibit perinatal lethality, indicating a large degree of functional overlap between the isoforms of the serine/threonine kinase Akt. The present study aimed to determine the cooperative contribution of Akt1 and Akt2 on the structure and contractile function of adult hearts. To generate an inducible, cardiomyocyte-restricted Akt2 knockout (KO) model, Akt2 mice were crossed with tamoxifen-inducible MerCreMer transgenic (MCM) mice and germline Akt1 mice to generate the following genotypes:Akt1; Akt2 (WT), Akt2; α-MHC-MCM (iAkt2 KO), Akt1, and Akt1; Akt2; α-MHC-MCM mice (Akt1/iAkt2 KO).

Insulin-like growth factor-1 signaling in cardiac aging.

Cardiovascular disease (CVD) is the leading cause of death in most developed countries. Aging is associated with enhanced risk of CVD. Insulin-like growth factor-1 (IGF-1) binds to its cognate receptor, IGF-1 receptor (IGF-1R), and exerts pleiotropic effects on cell growth, differentiation, development, and tissue repair.

Glucose transporter 4-deficient hearts develop maladaptive hypertrophy in response to physiological or pathological stresses.

Pathological cardiac hypertrophy may be associated with reduced expression of glucose transporter 4 (GLUT4) in contrast to exercise-induced cardiac hypertrophy, where GLUT4 levels are increased. However, mice with cardiac-specific deletion of GLUT4 (G4H) have normal cardiac function in the unstressed state. This study tested the hypothesis that cardiac GLUT4 is required for myocardial adaptations to hemodynamic demands.

Diabetic cardiomyopathy: where we are and where we are going.

The global burden of diabetes mellitus and its related complications are currently increasing. Diabetes mellitus affects the heart through various mechanisms including microvascular impairment, metabolic disturbance, subcellular component abnormalities, cardiac autonomic dysfunction, and a maladaptive immune response. Eventually, diabetes mellitus can cause functional and structural changes in the myocardium without coronary artery disease, a disorder known as diabetic cardiomyopathy (DCM).

The microRNA miR-124 inhibits vascular smooth muscle cell proliferation by targeting S100 calcium-binding protein A4 (S100A4).

S100 calcium-binding protein A4 (S100A4) induces proliferation and migration of vascular smooth muscle cells (VSMCs). We aimed to find the microRNA regulating S100A4 expression. S100A4 transcripts are abruptly increased in the acute phase of carotid arterial injury 1 day later (at day 1) but gradually decreases at days 7 and 14.

Efficacy and safety of gemigliptin, a dipeptidyl peptidase-4 inhibitor, in patients with type 2 diabetes mellitus inadequately controlled with combination treatment of metformin and sulphonylurea: a 24-week, multicentre, randomized, double-blind, placebo-controlled study (TROICA study).

Aims: To assess the efficacy and safety of gemigliptin, a dipeptidyl peptidase-4 inhibitor, added to metformin and sulphonylurea in patients with type 2 diabetes (T2DM).

Materials And Methods: We conducted a randomized, double-blind, placebo-controlled trial in 219 Korean patients inadequately controlled with metformin and glimepiride. Participants were randomized to gemigliptin 50 mg once daily or placebo added to metformin and glimepiride.