Relationship between Regional Fat Distribution and Hypertrophic Cardiomyopathy Phenotype

Female obesity: clinical and psychological assessment toward the best treatment

Obesity is a heterogeneous condition which results from complex interactions among sex/gender, sociocultural, environmental, and biological factors. Obesity is more prevalent in women in most developed countries, and several clinical and psychological obesity complications show sex-specific patterns. Females differ regarding fat distribution, with males tending to store more visceral fat, which is highly correlated to increased cardiovascular risk. Although women are more likely to be diagnosed with obesity and appear more motivated to lose weight, as confirmed by their greater representation in clinical trials, males show better outcomes in terms of body weight and intra-abdominal fat loss and improvements in the metabolic risk profile. However, only a few relatively recent studies have investigated gender differences in obesity, and sex/gender is rarely considered in the assessment and management of the disease. This review summarizes the evidence of gender differences in obesity prevalence, contributing factors, clinical complications, and psychological challenges. In addition, we explored gender differences in response to obesity treatments in the specific context of new anti-obesity drugs.

The association between continuous metabolic syndrome score and its components with electrocardiographic abnormalities in community-dwelling older adults: the Bushehr elderly health (BEH) program

BACKGROUND

Metabolic syndrome (MetS) known as a risk factor for cardiovascular diseases (CVDs) has developed into a major source of health issue, especially for the elderly. In the present study, we investigated the association between continuous MetS (cMetS) score and its components with electrocardiographic (ECG) abnormalities in the community-dwelling older adults.

METHODS

This cross-sectional study is derived from the second phase of BEH cohort study which is conducted on individuals aged over 60 years old. Standard 12-lead ECGs were recorded and coded by qualified physicians and continuous values of metabolic syndrome risk scores (cMetS) were measured. Data regarding socio-demographic, medical history, and lifestyle variables were collected by trained interviewers. The multinomial regression analysis was used to investigate the relationship between cMetS and its components with ECG abnormalities in the included participants.

RESULTS

2426 individuals (mean age ± standard deviation: 69.30 ± 6.33 years) were included in the final analysis. Overall, 22.5% of the participants showed ECG abnormalities. Among these, 8.0% (n = 139) of participants had minor and 14.6% (n = 354) had major ECG abnormalities. In the final models, cMetS (OR = 1.04), mean arterial pressure (MAP((OR = 1.01), and higher fasting blood glucose (FBG) (OR = 1.01) increased the risk of ECG abnormalities (p < 0.05). Also, cMetS (OR = 1.05) and MAP (OR = 1.02) were associated with an increased risk of major ECG abnormalities (p < 0.05).

CONCLUSION

MetS and MAP were significantly associated with ECG abnormalities. The results of the present study suggest that ECG screening in the older population with MetS could potentially help to detect those at the higher risk of CVDs.

Roles of the crucial mitochondrial DNA in hypertrophic cardiomyopathy prognosis and diagnosis: A review

Mitochondrial DNA is implicated in hypertrophic cardiomyopathy (HCM) development. We aimed to identify valuable mtDNAs that contribute to the development of HCM. Differentially expressed mitochondrial DNAs (DEMGs) between HCM and controls were screened. GO and KEGG functional enrichment analyses were performed, and the optimum genes were explored using the LASSO regression mode and SVM-RFE model. A diagnostic scoring model was constructed and verified using ROC curves. Mitochondria-based subtypes were identified. Immune performance among the subtypes including immune cells, immune checkpoint genes, and HLA family genes was analyzed. Finally, an mRNA-transcription factor (TF)-miRNA network was constructed using Cytoscape software. Twelve DEMGs in HCM were selected. Among them, 6 DEMGs, including PDK4, MGST1, TOMM40, LYPLAL1, GATM, and CPT1B were demonstrated as DEMGs at the point of intersection of Lasso regression and SVM-RFE. The ROC of the model for the training and validation datasets was 0.999 and 0.958, respectively. Two clusters were divided, and 4 immune cell types were significantly different between the 2 clusters, including resting mast cells, macrophages M2, and plasma cells. Nine upregulated KEGG pathways were enriched in cluster 1 vs. cluster 2 including O-glycan biosynthesis, the ErbB signaling pathway, and the GnRH signaling pathway. Meanwhile, 49 down-regulated pathways were enriched such as the toll-like signaling pathway and natural killer cell-mediated cytotoxicity pathway. The 6 gene-based mRNA-TF-miRNA networks included other 133 TFs and 18 miRNAs. Six DEMGs in HCM, including PDK4, MGST1, TOMM40, LYPLAL1, GATM, and CPT1B, can be indicative of HCM prognosis or disease progression.

Unraveling the Genotype-Phenotype Relationship in Hypertrophic Cardiomyopathy: Obesity-Related Cardiac Defects as a Major Disease Modifier

Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiomyopathy and is characterized by asymmetric septal thickening and diastolic dysfunction. More than 1500 mutations in genes encoding sarcomere proteins are associated with HCM. However, the genotype‐phenotype relationship in HCM is incompletely understood and involves modification by additional disease hits. Recent cohort studies identify obesity as a major adverse modifier of disease penetrance, severity, and clinical course. In this review, we provide an overview of these clinical findings. Moreover, we explore putative mechanisms underlying obesity‐induced sensitization and aggravation of the HCM phenotype. We hypothesize obesity‐related stressors to impact on cardiomyocyte structure, metabolism, and homeostasis. These may impair cardiac function by directly acting on the primary mutation‐induced myofilament defects and by independently adding to the total cardiac disease burden. Last, we address important clinical and pharmacological implications of the involvement of obesity in HCM disease modification.

Echocardiography in the Era of Obesity

Patients with obesity are at increased risk for coronary artery disease and heart failure and often present with symptoms of dyspnea, fatigue, edema, or chest pain. Echocardiography is frequently used to help distinguish whether these symptoms are due to cardiac disease. Unfortunately, obesity has a significant impact on image quality because of signal attenuation. Ultrasound-enhancing agents may improve the detection of structural remodeling and subclinical left ventricular dysfunction in patients with obesity. Assessment of chamber sizes and cardiac remodeling in severely obese subjects must be interpreted with caution, however, as the current recommendations for indexing cardiac chamber sizes to body size may lead to false conclusions about chamber volumes or mass, particularly in settings in which weight is changing. As a result of increases in stroke volume and cardiac output, obesity may exacerbate hemodynamic compromise in obstructive structural or valvular disease. With regard to assessment of ischemic heart disease, stress echocardiography can effectively risk-stratify patients with obesity and may have advantages over other noninvasive modalities. In general, transesophageal echocardiography is safe in patients with obesity, although some precautions should be observed. Stress echocardiography using the transesophageal approach is an alternative for preoperative or ischemia evaluation in patients with suboptimal transthoracic views.

Epicardial fat: the role of testosterone and lipid metabolism in a cohort of patients with Klinefelter syndrome

CONTEXT

Klinefelter syndrome (KS), in which subjects have additional copies of X chromosomes, is the most common male sex chromosome abnormality, with a prevalence of 1 in 660 and an incidence of about 1 in 500-700 newborns. Its sign and symptoms include infertility, generally low testosterone levels, and an increased prevalence of obesity and metabolic syndrome. Epicardial fat thickness (EFT) reflects visceral adiposity rather than general obesity.

OBJECTIVE

The aim of this study was to analyze echocardiographic EFT in a cohort of patients with KS in comparison with non-obese and obese euploid controls, and to evaluate its correlation with biochemical parameters.

DESIGN, SETTING AND PARTICIPANTS

Two hundred and twenty-one KS patients referred to our Rare Endocrine Diseases clinic and 77 age-matched controls underwent Doppler echocardiography and a full investigation of anthropometric and body composition, Serum levels of total testosterone (T), estradiol (E2), sex hormone binding globulin (SHBG), fasting plasma glucose, insulin, cholesterol and triglycerides were obtained. All participants underwent dual energy X-ray absorptiometry (DEXA) scan to assess truncal body fat (TrBF).

MAIN OUTCOME MEASURE

EFT, body composition and metabolic parameters in KS patients and how they are affected by genotype.

RESULTS

EFT was greater in KS patients than in healthy non-obese (NOb) controls, but lower than in obese (OB) controls. When KS patients were divided into groups (hypogonadal; eugonadal; receiving testosterone replacement therapy [TRT]), EFT was greater in hypogonadal patients than in NOb controls and eugonadal patients, but showed no difference from the OB controls or TRT patients. Hypogonadal patients showed increased TrBF in comparison with NOb controls and eugonadal and TRT patients, and similar TrBF to OB controls. As expected, there was a strong correlation between BMI and EFT in both KS patients and controls (P < 0.0001). In contrast, there was a strong inverse correlation between testosterone and EFT in the control group, but not in KS patients. EFT was significantly correlated with TrBF in both populations (P < 0.0001). Multivariate analyses showed that the major determinants of both EFT and TrBF were BMI and the presence of KS itself. Testosterone and triglycerides were not included as variables in the models.

CONCLUSION

EFT in hypogonadal KS subjects was similar to that of the obese eugonadal controls. Even though there was a direct correlation between BMI and EFT in both populations, the influence of TrBF on EFT was stronger. The presence of the supernumerary X chromosome appeared to be one of the strongest determinants of EFT and TrBF, independent of testosterone levels.

Type 2 diabetes: Does pancreatic fat really matter?

With the increasing prevalence of obesity, the interest of research in nonalcoholic fatty pancreas disease (NAFPD) has grown. Even though the pancreas appears more susceptible to lipid accumulation compared with the liver, NAFPD has been less investigated due to the limits in detecting techniques. Several definitions and synonyms for NAFPD are used by authors and can be misleading. This, together with differences in methodology and ethnicity, make the integration and comparison of studies on this topic challenging. NAFPD could be used as an early indicator of ectopic fat deposition, which is recognized as a key factor of obesity cardio-metabolic complications. However, evidence that NAFPD has a pathogenetic role in type 2 diabetes is also emerging. This article reviews the current state of knowledge on the clinical and pathophysiologic relevance of NAFPD in β-cell function and insulin resistance.

Obesity phenotypes: depot-differences in adipose tissue and their clinical implications

Obesity, defined as excess fat mass, increases risks for multiple chronic diseases, such as type 2 diabetes, cardiovascular disease, and several types of cancer. Beyond adiposity per se, the pattern of fat distribution, android or truncal as compared to gynoid or peripheral, has a profound influence on systemic metabolism and hence risk for obesity complications. Not only factors as genetics, environment, gender, and age account for the apparent compartmentalization of white adipose tissue (WAT) in the body. Indeed, the heterogeneity among different anatomical depots also appears to stem from their intrinsic diversity, including cellular developmental origin, proliferative capacity, glucose and lipid metabolism, insulin sensitivity, cytokine pattern, thermogenic ability, and vascularization. Under the obese condition, these depot-specific differences translate into specific WAT distribution patterns, giving rise to different cardiometabolic consequences. This review summarizes the clinical and mechanistic evidence for the depot-specific differences and the phenotypic characteristics of different WAT depots that link their depot-specific biology to obesity-specific complications.

MicroRNA 21 is up-regulated in adipose tissue of obese diabetic subjects

We investigated miR21 expression in omental (OAT) and subcutaneous adipose tissue (SAT) from 16 obese subjects undergoing bariatric surgery. Patients were divided into two age- and BMI-matched groups according to the presence of type 2 diabetes (T2D). miR21 was not differently expressed in OAT and SAT. However, miR21 expression was two folds greater in adipose tissue in patients with T2D. Accordingly, in primary cultures of adipocytes from non diabetic overweight subjects, miR21 expression increased after 24-h exposure to high glucose and insulin. In conclusion, miR21 appears linked to insulin-resistance deterioration within its pathophysiologic progression from obesity to T2D.