Dysfunctional adiposity index as a marker of adipose tissue morpho-functional abnormalities and metabolic disorders in apparently healthy subjects

The Potential of Metabolomics as a Tool for Identifying Biomarkers Associated with Obesity and Its Complications: A Scoping Review

Obesity and its related diseases, such as type 2 diabetes (T2DM), cardiovascular disease (CVD), and metabolic fatty liver disease (MAFLD), require new diagnostic markers for earlier detection and intervention. The aim of this study is to demonstrate the potential of metabolomics as a tool for identifying biomarkers associated with obesity and its comorbidities in every age group. The presented systematic review makes an important contribution to the understanding of the potential of metabolomics in identifying biomarkers of obesity and its complications, especially considering the influence of branched-chain amino acids (BCAAs), amino acids (AAs) and adipokines on the development of T2DM, MAFLD, and CVD. The unique element of this study is the combination of research results from the last decade in different age groups and a wide demographic range. The review was based on the PubMed and Science Direct databases, and the inclusion criterion was English-language original studies conducted in humans between 2014 and 2024 and focusing on the influence of BCAAs, AAs or adipokines on the above-mentioned obesity complications. Based on the PRISMA protocol, a total of 21 papers were qualified for the review and then assigned to a specific disease entity. The collected data reveal that elevated levels of BCAAs and some AAs strongly correlate with insulin resistance, leading to T2DM, MAFLD, and CVD and often preceding conventional clinical markers. Valine and tyrosine emerge as potential markers of MAFLD progression, while BCAAs are primarily associated with insulin resistance in various demographic groups. Adipokines, although less studied, offer hope for elucidating the metabolic consequences of obesity. The review showed that in the case of CVDs, there is still a lack of studies in children and adolescents, who are increasingly affected by these diseases. Moreover, despite the knowledge that adipokines play an important role in the pathogenesis of obesity, there are no precise findings regarding the correlation between individual adipokines and T2DM, MAFLD, or CVD. In order to be able to introduce metabolites into the basic diagnostics of obesity-related diseases, it is necessary to develop panels of biochemical tests that will combine them with classical markers of selected diseases.

The dysfunctional adiposity index is a clinical surrogate of pericardial fat in adults without premature CVD: A sub-analysis of the GEA Mexican study control group

BACKGROUND AND AIM

The Dysfunctional Adiposity Index (DAI) is a clinical surrogate for evaluating adipose tissue functionality and cardiometabolic health. However, its association with Pericardial Fat Volume (PFV) has not been tested. The aim of this study was to evaluate DAI- PFV association, stratified by type 2 diabetes (T2D) status, and identify DAI thresholds for detecting increased PFV among patients without premature CVD.

METHODS AND RESULTS

Participants from the GEA-Mexican study underwent a computed tomography scan to measure PFV. Adjusted logistic regression analyses tested the association between DAI and PFV. AUROC curves evaluated DAI's ability to identify elevated PFV (≥57.57 cm³), and the Youden method determined DAI thresholds, along with diagnostic metrics. The study analyzed 997 participants (women: 55%; mean age: 54 ± 9 years; median PFV: 42 cm³ [IQR: 29-58]), with a 13% prevalence of T2D. DAI was positively associated with elevated PFV (OR: 1.33, 95% CI: 1.07-1.70), which was more pronounced among subjects with T2D (OR: 3.01, 95% CI: 1.41-6.40). DAI thresholds were established for all participants (>1.176), individuals without T2D (>1.003), and with T2D (>1.936), yielding sensitivities of 71%, 81%, and 57%, and specificities of 48%, 38%, and 75%, respectively. The adjusted logistic regression tied DAI thresholds to a 1.68-fold elevation in PFV for all, 2.06-fold for those without T2D, and 6.81-fold for those with T2D.

CONCLUSION

DAI was positively associated with increased PFV, particularly among participants with T2D. Established DAI thresholds demonstrated good diagnostic values for detecting increased PFV. DAI could serve as an accessible marker to identify PF in clinical settings.

Rare Variants of Obesity-Associated Genes in Young Adults with Abdominal Obesity

The increase in the prevalence of overweight, obesity and associated diseases is a serious problem. The aim of the study was to identify rare variants in obesity-associated genes in young adults with abdominal obesity in our population and to analyze information about these variants in other populations. Targeted high-throughput sequencing of obesity-associated genes was performed (203 young adults with an abdominal obesity phenotype). In our study, all of the 203 young adults with abdominal obesity had some rare variant in the genes associated with obesity. The widest range of rare and common variants was presented in ADIPOQ, FTO, GLP1R, GHRL, and INS genes. The use of targeted sequencing and clinical criteria makes it possible to identify carriers of rare clinically significant variants in a wide range of obesity-associated genes and to investigate their influence on phenotypic manifestations of abdominal obesity.

The Role of Different Methods in Defining Cardiometabolic Risk and Metabolic Syndrome in Women with Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is one of the most frequent endocrine illnesses, often accompanied by visceral adiposity and metabolic syndrome (MetS). Visceral adiposity is an accurate predictor of MetS and cardiometabolic risk. This study aims to evaluate different anthropometric indices that can be used in PCOS and MetS risk assessment. A total of 66 women with PCOS (50%) and 66 controls (50%) were included, and clinical and biochemical parameters were evaluated. The body mass index (BMI), body shape index (ABSI), body roundness index (BRI), dysfunctional adiposity index (DAI), lipid accumulation (LAP) index, and visceral adiposity index (VAI) were calculated. The means of all indices were higher in the PCOS group (p < 0.05). The marker with the lowest discriminatory ability for PCOS and MetS was ABSI (AUC = 0.762 and AUC = 0.714, respectively, p = 0.000). According to the multivariate logistic regression model, the VAI and WC are strong predictors of PCOS (AUC, 98%; accuracy, 92%; sensitivity, 92%; and specificity, 91%), and WC, LAP index, and BRI are strong predictors of MetS (AUC, 0.95%; accuracy, 86%; sensitivity, 83%; and specificity, 88%). The use of different anthropometric indices in the detection of PCOS and MetS may allow for early diagnosis and treatment, and are simple and cost-effective.

Exercise and Weight Management: The Role of Leptin-A Systematic Review and Update of Clinical Data from 2000-2022

A well-balanced metabolism means a lower risk for metabolism-related neuropsychiatric disorders. Leptin is a secretory adipokine involved in the central control of appetite that appears to play a role in the etiology of feeding-related disorders. Additionally, the influence of exercise on feeding behaviors potentially modulates the circulation of metabolites that signal through the central nervous system. In this systematic review, we collected the recent clinical evidence on the effect of exercise on leptin concentrations in health individuals published from 2000 to 20 September 2022, according to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA 2020 statement). Six hundred and thirty-eight papers were retrieved and forty-eight papers were included in the qualitative synthesis. Data supports that exercise positively influences appetite via enhancing peripheral and central leptin signaling (reuptake), especially during weight loss. Exercise modulation of leptin signaling through leptin receptors helps to stabilize increases in food intake during periods of negative energy balance, prior to a decrease in the body fat tissue content. At a high intensity, exercise appears to counteract leptin resistance.

Visceral adipose tissue is an independent predictor and mediator of the progression of coronary calcification: a prospective sub-analysis of the GEA study

BACKGROUND

Coronary artery calcium (CAC) improves cardiovascular event prediction. Visceral adipose tissue (VAT) is a cardiometabolic risk factor that may directly or through its related comorbidities determine the obesity-related risk. A clinical VAT estimator could allow an efficient evaluation of obesity-related risk. We aimed to analyze the effect of VAT and its related cardiometabolic risk factors on CAC progression.

METHODS

CAC was quantified at baseline and after 5 years by computed tomography (CT), determining its progression. VAT and pericardial fat were measured by CT and estimated by a clinical surrogate (METS-VF). Considered cardiometabolic risk factors were: peripheral insulin resistance (IR), HOMA-IR, adipose tissue IR (ADIPO-IR), and adiponectin. Factors independently associated to CAC progression were analyzed by adjusted Cox proportional hazard models, including statin use and ASCVD risk score as covariates. We performed interaction and mediation models to propose possible pathways for CAC progression.

RESULTS

The study included 862 adults (53 ± 9 years, 53% women), incidence CAC progression rate: 30.2 (95% CI 25.3-35.8)/1000 person-years. VAT (HR: 1.004, 95% CI 1.001-1.007, p < 0.01) and METS-VF (HR: 1.001, 95% CI 1.0-1.001, p < 0.05) independently predicted CAC progression. VAT-associated CAC progression risk was evident among low-risk ASCVD subjects, and attenuated among medium-high-risk subjects, suggesting that traditional risk factors overcome adiposity in the latter. VAT mediates 51.8% (95% CI 44.5-58.8%) of the effect attributable to IR together with adipose tissue dysfunction on CAC progression.

CONCLUSIONS

This study supports the hypothesis that VAT is a mediator of the risk conferred by subcutaneous adipose tissue dysfunction. METS-VF is an efficient clinical surrogate that could facilitate the identification of at-risk adiposity subjects in daily clinical practice.

Functionally Significant Variants in Genes Associated with Abdominal Obesity: A Review

The high prevalence of obesity and of its associated diseases is a major problem worldwide. Genetic predisposition and the influence of environmental factors contribute to the development of obesity. Changes in the structure and functional activity of genes encoding adipocytokines are involved in the predisposition to weight gain and obesity. In this review, variants in genes associated with adipocyte function are examined, as are variants in genes associated with metabolic aberrations and the accompanying disorders in visceral obesity.

Determination of cardiovascular risk in Spanish veterinarians using different scaling methods

Introduction

Cardiovascular diseases are responsible for a significant morbimortality rate around the world. Due to the characteristics of their work, health care professionals, including veterinarians, are more prone to present this type of pathology.

Objectives

To determine the level of cardiovascular risk using different scales in a group of veterinarians.

Methods

A descriptive and cross-sectional study of 610 Spanish veterinarians was conducted to assess cardiovascular risk scores, including 14 overweight and obesity scales, six fatty liver scales, six cardiovascular risk scales, four atherogenic indices, and three metabolic syndrome scales.

Results

The prevalence of obesity among women was 7.95%, and 17.53% among men. Hypertension was present in 15.23% of women and 24.68% of men. Dyslipidemia affected 45% of women and 58.64% of men. The prevalence of metabolic syndrome according to the International Diabetes Federation criteria was slightly over 10% while 10.90% of women and 14.93% of men showed moderate to high values on the Registre Gironí del Cor scale.

Conclusions

There is a moderate to high level of cardiovascular risk among veterinarians in this group.

Is insulin resistance tissue-dependent and substrate-specific? The role of white adipose tissue and skeletal muscle

Insulin resistance (IR) refers to a reduction in the ability of insulin to exert its metabolic effects in organs such as adipose tissue (AT) and skeletal muscle (SM), leading to chronic diseases such as type 2 diabetes, hepatic steatosis, and cardiovascular diseases. Obesity is the main cause of IR, however not all subjects with obesity develop clinical insulin resistance, and not all clinically insulin-resistant people have obesity. Recent evidence implies that IR onset is tissue-dependent (AT or SM) and/or substrate-specific (glucometabolic or lipometabolic). Therefore, the aims of the present review are 1) to describe the glucometabolic and lipometabolic activities of insulin in AT and SM in the maintenance of whole-body metabolic homeostasis, 2) to discuss the pathophysiology of substrate-specific IR in AT and SM, and 3) to highlight novel validated tests to assess tissue and substrate-specific IR that are easy to perform in clinical practice. In AT, glucometabolic IR reduces glucose availability for glycerol and fatty acid synthesis, thus decreasing the esterification and synthesis of signaling bioactive lipids. Lipometabolic IR in AT impairs the antilipolytic effect of insulin and lipogenesis, leading to an increase in circulating FFAs and generating lipotoxicity in peripheral tissues. In SM, glucometabolic IR reduces glucose uptake, whereas lipometabolic IR impairs mitochondrial lipid oxidation, increasing oxidative stress and inflammation, all of which lead to metabolic inflexibility. Understanding tissue-dependent and substrate-specific IR is of paramount importance for early detection before clinical manifestations and for the development of more specific treatments or direct interventions to prevent chronic life-threatening diseases.

Self-reported dietary omega-3 polyunsaturated fatty acids are associated with adipose tissue markers and glucose metabolism in apparently healthy subjects

BACKGROUND

Plasminogen activator inhibitor 1 (PAI-1) and resistin are associated with dysfunctional adipose tissue (AT)-related metabolic complications. The role of dietary eicosapentaenoic (EPA) and docosahexaenoic (DHA) fatty acids in this relationship is unknown.

AIM

To investigate the association of EPA and DHA with PAI-1 and resistin, as well as the role of this association on the glucose metabolism of apparently healthy subjects.

SUBJECTS AND METHODS

Thirty-six healthy individuals were included. Validated food frequency questionnaires were used to analyse dietary habits. Inflammatory and glucose metabolism markers were quantified. Subcutaneous AT samples were obtained, and adipocyte number, area, and macrophage content were assessed.

RESULTS

In 36 subjects aged 56 ± 8 years and with a body mass index of 26 ± 4 kg/m², _logEPA, and _logDHA showed significant association with _logresistin and a marginal association with PAI-1. Adipocyte number, area, and _lognumber of macrophages per adipocyte significantly correlated with PAI-1 but not with _logresistin. Although _logEPA and _logDHA were independently associated with _loginsulin, _loginsulin resistance, and C-Peptide, the addition of _logresistin, but not of PAI-1, into the multivariable model, abolished the associations.

CONCLUSIONS

EPA and DHA could modulate glucose metabolism across AT functional states. Our data indicate that this association is independent of other metabolic risk factors.

The CUN-BAE, Deurenberg Fat Mass, and visceral adiposity index as confident anthropometric indices for early detection of metabolic syndrome components in adults

There is no definition for the metabolic syndrome; visceral obesity, elevated lipids and glucose, and hypertension coexist. The aim of the study is to determine which anthropometric indicators best determine it. Cross-sectional study in 418,343 Spanish workers. Metabolic syndrome was determined using the NCEP-ATPIII, IDF and JIS criteria. The anthropometric variables studied were: body mass index, waist circumference, waist-to-height ratio, CUNBAE, Deuremberg formula, body fat index, body surface index, normalized weight adjusted index, body roundness index, body shape index, visceral adiposity index (VAI), dysfunctional adiposity index, conicity index, metabolic score for visceral fat (METS-VF), waist triglyceride index. In men, the anthropometric indices with the largest areas under the ROC curve are VAI with ATPIII criteria and JIS. If we use the IDF criteria: waist circumference and METS-VF, with the same result. In women, the largest areas under the curve were observed with the Deuremberg formula in both ATPIII and JIS while with the IDF criteria it is METS-VF. The most useful anthropometric indices for identifying metabolic syndrome are CUN-BAE and Deuremberg, followed by the VAI. A single definition of metabolic syndrome should be agreed to determine the best anthropometric index with predictive capacity for its diagnosis.

Leptin-A Potential Bridge between Fat Metabolism and the Brain's Vulnerability to Neuropsychiatric Disorders: A Systematic Review

BACKGROUND

Obesity and being overweight have been described as potential causes of neurological disorders. Leptin, a peptide expressed in fat tissue, importantly participates in energy homeostasis and storage and has recently been identified for its signaling receptors in neuronal circuits of the brain.

AIM

To elucidate whether the endogenous modulation of leptin can be a protection against neuropsychiatric disorders.

METHOD

A systematic review was performed in accordance with the PRISMA-P method, and reports of studies containing data of leptin concentrations in healthy individuals with or without obesity were retrieved from the PubMed database, using the combinations of Mesh terms for "Leptin" and "Metabolism".

RESULTS

Forty-seven randomized and non-randomized controlled trials, dating from 2000 to 2021, were included in the qualitative synthesis.

DISCUSSION AND CONCLUSIONS

Leptin secretion displays a stabilizing pattern that is more sensitive to a negative energy intake imbalance. Leptin levels influence body weight and fat mass as a pro-homeostasis factor. However, long-term exposure to elevated leptin levels may lead to mental/behavioral disorders related to the feeding and reward systems.

Adipose Tissue and Biological Factors. Possible Link between Lymphatic System Dysfunction and Obesity

The World Health Organization (WHO) has recognised obesity as one of the top ten threats to human health. Obesity is not only a state of abnormally increased adipose tissue in the body, but also of an increased release of biologically active metabolites. Moreover, obesity predisposes the development of metabolic syndrome and increases the incidence of type 2 diabetes (T2DM), increases the risk of developing insulin resistance, atherosclerosis, ischemic heart disease, polycystic ovary syndrome, hypertension and cancer. The lymphatic system is a one-directional network of thin-walled capillaries and larger vessels covered by a continuous layer of endothelial cells that provides a unidirectional conduit to return filtered arterial and tissue metabolites towards the venous circulation. Recent studies have shown that obesity can markedly impair lymphatic function. Conversely, dysfunction in the lymphatic system may also be involved in the pathogenesis of obesity. This review highlights the important findings regarding obesity related to lymphatic system dysfunction, including clinical implications and experimental studies. Moreover, we present the role of biological factors in the pathophysiology of the lymphatic system and we propose the possibility of a therapy supporting the function of the lymphatic system in the course of obesity.