Adipose tissue dysfunction contributes to obesity related metabolic diseases

Anthropometric metabolic subtypes and health outcomes: A data-driven cluster analysis

AIMS

The aims of the study were to develop and validate WHOLISTIIC, a data-driven cluster analysis for identifying anthropometric metabolic subtypes.

MATERIALS AND METHODS

K-means cluster analysis was performed in 397 424 UK Biobank participants based on five domains, that is, central obesity (waist-to-height ratio), general obesity (body mass index [BMI]), limb strength (handgrip strength), insulin resistance (triglyceride to high-density lipoprotein cholesterol [HDLc] ratio) and inflammatory condition (neutrophil-to-lymphocyte ratio). Replication was done in the NHANES. Cox proportional hazards regression models were used to estimate the associations of clusters with incident adverse health outcomes.

RESULTS

Six replicable clusters were identified. Compared with individuals in cluster 1 (lowest BMI with preserved handgrip strength), individuals in cluster 2 (highest handgrip strength) were not at increased risk of all-cause mortality despite higher BMI, but had small yet significant increased risks of cardiovascular mortality, incident major adverse cardiovascular events (MACE), chronic renal failure and decreased risks of mortality due to respiratory disease, as well as incident dementia; individuals in cluster 3 (lowest handgrip strength and borderline elevated BMI), cluster 4 (highest triglyceride-to-HDLc ratio and moderately elevated BMI), cluster 5 (highest neutrophil-to-lymphocyte ratio and borderline elevated BMI) and cluster 6 (highest BMI) had substantially increased risks of all-cause, cardiovascular, and cancer mortality, incident MACE and chronic renal failure. The associations of anthropometric clusters with the risk of mortality were replicated in the NHANES cohort.

CONCLUSIONS

Anthropometric metabolic subtypes identified with easily accessible parameters reflecting multifaceted pathology of overweight and obesity were associated with distinct risks of long-term adverse health outcomes.

Optimized RNA sequencing deconvolution illustrates the impact of obesity and weight loss on cell composition of human adipose tissue

OBJECTIVE

Cellular heterogeneity of human adipose tissue is linked to the pathophysiology of obesity and may impact the response to energy restriction and changes in fat mass. Herein, we provide an optimized pipeline to estimate cellular composition in human abdominal subcutaneous adipose tissue (ASAT) bulk RNA sequencing (RNA-seq) datasets using a single-nuclei RNA-seq signature matrix.

METHODS

A deconvolution pipeline for ASAT was optimized by benchmarking publicly available algorithms using a signature matrix derived from ASAT single-nuclei RNA-seq data from 20 adults and then applied to estimate ASAT cell-type proportions in publicly available obesity and weight loss studies.

RESULTS

Individuals with obesity had greater proportions of macrophages and lower proportions of adipocyte subpopulations and vascular cells compared with lean individuals. Two months of diet-induced weight loss increased the estimated proportions of macrophages; however, 2 years of diet-induced weight loss reduced the estimated proportions of macrophages, thereby suggesting a biphasic nature of cellular remodeling of ASAT during weight loss.

CONCLUSIONS

Our optimized high-throughput pipeline facilitates the assessment of composition changes of highly characterized cell types in large numbers of ASAT samples using low-cost bulk RNA-seq. Our data reveal novel changes in cellular heterogeneity and its association with cardiometabolic health in humans with obesity and following weight loss.

Cardiometabolic Risk in Chronic Spinal Cord Injury: A Systematic Review with Meta-Analysis and Temporal and Geographical Trends

Objectives: This systematic review with meta-analysis compared cardiometabolic syndrome (CMS) in adults with chronic (≥1 year) spinal cord injury (SCI) to non-SCI individuals (controls) and athletes, analyzing the effect of specific injury characteristics and exploring temporal and geographical trends. Methods: Ovid Medline, Embase, Cochrane, CINAHL, Scopus, and Web of Science were searched from inception to September 2024. Adults with chronic SCI were included based on observational and baseline data derived from experimental studies. Quality Assessment Criteria for Evaluating Primary Research Papers from a Variety of Fields assessed quality. Weighted means with 95% bootstrapped confidence intervals (CI) were computed for risk stratification. Group differences were assessed using random effects meta-analysis, calculating weighted mean differences with 95% bootstrapped CI. Temporal and geographical trends were evaluated with linear regression based on sample-size-weighted distributions and relevant covariates. Results: Of 31,163 identified records, 471 studies were included (n ≤ 31,782 SCI participants). CMS was present in men with SCI, paraplegia, tetraplegia, and injuries above T6; men with complete SCI (AIS A); and men and women with motor-complete SCI (AIS A-B). Compared to controls, adults with SCI had a lower body mass index (BMI), higher total and visceral fat, and worse lipid and carbohydrate profiles, including increased insulin resistance (IR). Tetraplegia was associated with greater visceral fat, poorer glycemic control, and lower BMI, insulin sensitivity, high-density lipoprotein-cholesterol (HDL-C), and triglycerides than paraplegia. Motor-complete SCI had lower BMI, HDL-C, and fasting glucose than motor-incomplete injuries. Injuries above T6 had lower blood pressure and higher fasting insulin levels than those below T6. Athletes with SCI had a lower BMI, fat mass, and fasting glucose, and higher systolic blood pressure than non-athletes with SCI, but frequently presented with obesity and carbohydrate dysfunction. Temporal analysis revealed increasing obesity trends and improved systolic blood pressure, while other CMS risk factors remained unchanged. We also identified global variations in obesity, lipids, blood pressure, and carbohydrate patterns. Conclusions: With a large sample, we revealed a widespread cardiometabolic burden in chronic SCI, even among athletes. Specifically, obesity, IR, and hypoalphalipoproteinemia worsened with increasing injury severity, alongside rising obesity trends and geographic disparities in risk profiles. These patterns highlight the evolution of what was deemed an epidemic into a global cardiometabolic pandemic.

The Advanced Glycation End-Products (AGE)-Receptor for AGE System (RAGE): An Inflammatory Pathway Linking Obesity and Cardiovascular Diseases

The AGE (advanced glycation end-products)-RAGE (receptor for AGE) system is a pro-inflammatory pathway that contributes to the pathogenesis of obesity and obesity-related cardiovascular disorders (CVD). Circulating AGE and the soluble form of RAGE (sRAGE) has been suggested as a potential biomarker of CVD related to obesity. In this study, we aim to (1) summarize the current knowledge about the role of obesity in the onset and progression of CVD, (2) discuss the role of the AGE-RAGE system as a pathway promoting obesity and linking obesity to CVD, and (3) highlight available strategies for reducing AGE-RAGE system activation and the associated beneficial effects.

Identifying genetic overlaps in obesity and metabolic disorders unlocking unique and shared mechanistic insights

OBJECTIVE

Obesity has a high heritability and frequently co-occurs with metabolic disorders, indicating shared genetic susceptibility. The underlying causative genes and biological mechanisms of obesity and metabolic disorders remain predominantly elusive.

METHODS

The FinnGen R11 dataset, including over 450,000 subjects, was employed in conjunction with the Genotype-Tissue Expression Project (GTEx) v8 eQTls dataset to conduct cross-tissue transcriptome association studies, Functional Summary-based Imputation in single tissues, and Gene Analysis combined with Multimarker Analysis of Genomic Annotation, respectively, for identifying distinct and shared genetic architectures of obesity and metabolic disorders. We also employed RHOGE to ascertain the genetic correlation and putative causal directions between them. Subsequent Mendelian randomization, colocalization analyses, and other cell and tissue enrichment analyses were employed to enhance our understanding of the functional implications of these susceptibility genes.

RESULTS

A total of 35 genes were identified as obesity susceptibility and 10 genes linked to metabolic disorder susceptibility. Of these, three genes (MCM6, MAPRE3 and UBXN4) were identified as being shared. Mendelian randomization and colocalization analyses revealed the three shared genes have causal associations with obesity and metabolic disorders and serve as independent signals. Subsequent analyses indicated MCM6 may influence obesity and metabolic disorder risk by regulating DNA replication, cell proliferation, and interactions with chemical responses. MAPRE3 may confer protective effects against obesity and metabolic disorders through PAK Pathway, while UBXN4 may involve in regulating cholesterol metabolism.

CONCLUSION

Our study provides insight into the novel shared genetic mechanism between obesity and metabolic disorders and identifies potential targets for pharmacological intervention.

An overview of obesity-related complications: The epidemiological evidence linking body weight and other markers of obesity to adverse health outcomes

Obesity is a highly prevalent chronic multisystem disease associated with shortened life expectancy due to a number of adverse health outcomes. Epidemiological data link body weight and parameters of central fat distribution to an increasing risk for type 2 diabetes, hypertension, fatty liver diseases, cardiovascular diseases including myocardial infarction, heart failure, atrial fibrillation, stroke, obstructive sleep apnoea, osteoarthritis, mental disorders and some types of cancer. However, the individual risk to develop cardiometabolic and other obesity-related diseases cannot entirely be explained by increased fat mass. Rather than excess fat accumulation, dysfunction of adipose tissue may represent the mechanistic link between obesity and adverse health outcomes. There are people living with obesity who seem to be protected against the premature development of cardiometabolic diseases. On the other hand, people with normal weight may develop typical obesity diseases upon dysfunction of adipose tissue and predominantly visceral fat distribution. The mechanisms linking impaired function of adipose tissue in people with obesity include adipocyte hypertrophy, altered cellular composition, limited expandability of safe subcutaneous fat stores, ectopic fat deposition in visceral depots, the liver and other organs, hypoxia, a variety of stresses, inflammatory processes, and the release of pro-inflammatory, diabetogenic and atherogenic signals. Genetic and environmental factors might contribute either alone or via interaction with intrinsic biological factors to variation in adipose tissue function. There are still many open questions regarding the mechanisms of how increased body weight causes obesity-related disorders and whether these pathologies could be reversed. Evidence-based weight loss interventions using behaviour change, pharmacological or surgical approaches have clarified the beneficial effects of realistic and sustained weight loss on obesity-related complications as hard outcomes. This review focusses on recent advances in understanding epidemiological trends and mechanisms of obesity-related diseases. PLAIN LANGUAGE SUMMARY: Obesity is a chronic complex and progressive disease characterized by excessive fat deposition that may impair health and quality of life. Worldwide, the number of adults living with obesity has more than doubled since 1990. Obesity may lead to reduced life expectancy, because it increases the risk for type 2 diabetes, cardiovascular diseases (e.g., myocardial infarction, high blood pressure, stroke), fatty liver diseases, musculoskeletal diseases, chronic respiratory diseases, depression and certain types of cancer. However, not every person with obesity develops these diseases. For better prevention and treatment, it is important to understand the mechanisms linking high fat mass to obesity related diseases. It has become clear that fat mass alone cannot explain the higher risk of obesity complications. People with obesity can have either high or low risk of developing complications. Compared to people with a low risk for obesity complications those with a high risk to develop obesity related diseases are characterized by higher central fat deposition in the abdominal region, on average bigger fat cells, higher number of immune cells in adipose tissue and altered signals released from adipose tissue that may directly affect the brain, liver, vasculature and other organs. Both inherited and environment factors may cause these abnormalities of adipose tissue function. However, weight loss through behaviour changes (e.g., lower calorie intake, higher physical activity), medications or obesity surgery can improve health, quality of life and reduce the risk for obesity related diseases.

Obesity and insulinopenic type 2 diabetes differentially impact, bone phenotype, bone marrow adipose tissue, and serum levels of the cathelicidin-related antimicrobial peptide in mice

Obesity is a risk factor of developing type 2 diabetes (T2D) and metabolic complications, through systemic inflammation and insulin resistance. It has also been associated with increased bone marrow adipocytes along with increased bone fragility and fracture risk. However, the differential effects of obesity and T2D on bone fragility remain unclear. The cathelicidin-related antimicrobial peptide (CRAMP) is a multifunctional modulator of the innate immunity that has emerged as biomarker of cardiometabolic diseases. The aims of this study were i) to assess the differential impact between hyperinsulinemic obesity versus insulinopenic T2D, on bone phenotype and bone marrow adipose tissue (BMAT), and ii) to analyse the link with CRAMP expression and its circulating levels in the context of obesity and T2D. We used C57BL/6 J male mice models of obesity induced by high-fat diet (HFD), and of insulinopenic T2D induced by streptozotocin (STZ) treatment combined with HFD, reflecting the metabolic heterogeneity of the diseases. As compared to low-fat diet (LFD) control group after 16 weeks of feeding, the HFD mice exhibit a significant weight gain, moderate hyperglycaemia, impaired glucose tolerance and insulin sensitivity, and significant increase in serum insulin levels. This hyperinsulinemic obesity led to decreased trabecular (Tb.Th) and cortical thickness (Ct.Th) in the tibia, associated with significant BMAT expansion, in addition to increased subcutaneaous (SCAT) and visceral adipose tissue (VAT). No changes were observed in the circulating levels of CRAMP peptide neither in other bone parameters. While, STZ treatment in HFD/STZ group induced a more severe hyperglycaemia, glucose intolerance and insulin resistance, and hypoinsulinemia. We also observed a negative effect on the expansion of both SCAT and VAT, as well as lower increase in BMAT as compared to HFD group. However, these mice with insulinopenic T2D exhibit early decrease in trabecular number (Tb.N) in proximal tibia, progressively from 8 to 16 weeks of protocol, and impaired femoral biomechanical stiffness. These alterations are also accompanied with decreased circulating levels of the CRAMP peptide in the HFD/STZ mice. The CRAMP mRNA levels decreased in VAT of both HFD and HFD/STZ groups. Overall, these results provide novel insights into the differential negative impact of obesity versus T2D on bone microenvironment, and suggest a link between hyperglycaemia-induced bone quality alterations during insulinopenia, and impaired regulation of the cathelicidin peptide of the innate immunity. Further investigations are needed to elucidate this relationship.

Establishing the relationships between obesity and genetically predicted serum micronutrient levels: a multivariable Mendelian randomization analysis

BACKGROUND

Previous observational studies have indicated that circulating micronutrients may influence obesity risk. This study aimed to explore the causal relationship between micronutrient levels and obesity through multivariable Mendelian randomization (MR) analysis.

METHODS

Single nucleotide polymorphisms (SNPs) significantly associated with 15 micronutrients (selenium, zinc, copper, calcium, beta-carotene, folate, iron, magnesium, potassium, and vitamins A, B6, B12, C, D, and E) from published genome-wide association studies (GWAS) were used as instrumental variables (IVs). Three obesity-related datasets were obtained from the GWAS. Inverse variance weighted (IVW) is the main method used for MR analysis. Leave-one-out analysis, MR-Pleiotropy Residual Sum and Outlier method (MR-PRESSO), weighted median, and MR-Egger method were used to assess pleiotropy and heterogeneity.

RESULTS

Genetically predicted levels of circulating selenium and calcium are causally related to the risk of obesity (calcium odds ratio [OR]: 1.478, 95% confidence interval [CI] 1.128-1.935, p = 0.005; selenium OR: 1.478, 95% CI 1.128-1.935, p = 0.005). Multivariate MR analysis suggested a causal relationship between circulating selenium and calcium levels and obesity risk (calcium OR: 1.625, 95% CI 1.260-2.097; selenium OR: 1.080, 95% CI 1.003-1.163, p = 0.041). The p-value obtained in the Cochrane Q test, MR-Egger intercept test, and MR-PRESSO were > 0.05, suggesting no significant evidence of pleiotropy or heterogeneity.

CONCLUSION

Our study revealed, for the first time, a positive correlation between elevated circulating calcium and selenium levels and an increased obesity risk. These findings provide valuable insights into obesity's underlying mechanisms. Nevertheless, further large-scale clinical studies are required to confirm our results.

LEVEL OF EVIDENCE

Level III, Mendelian randomization.

Obesity and Adipose-Derived Extracellular Vesicles: Implications for Metabolic Regulation and Disease

Obesity, a global epidemic, is a major risk factor for chronic diseases such as type 2 diabetes, cardiovascular disorders, and metabolic syndrome. Adipose tissue, once viewed as a passive fat storage site, is now recognized as an active endocrine organ involved in metabolic regulation and inflammation. In obesity, adipose tissue dysfunction disrupts metabolic balance, leading to insulin resistance and increased production of adipose-derived extracellular vesicles (AdEVs). These vesicles play a key role in intercellular communication and contribute to metabolic dysregulation, affecting organs such as the heart, liver, and brain. AdEVs carry bioactive molecules, including microRNAs, which influence inflammation, insulin sensitivity, and tissue remodeling. In the cardiovascular system, AdEVs can promote atherosclerosis and vascular dysfunction, while those derived from brown adipose tissue offer cardioprotective effects. In type 2 diabetes, AdEVs exacerbate insulin resistance and contribute to complications such as diabetic cardiomyopathy and cognitive decline. Additionally, AdEVs are implicated in metabolic liver diseases, including fatty liver disease, by transferring inflammatory molecules and lipotoxic microRNAs to hepatocytes. These findings highlight the role of AdEVs in obesity-related metabolic disorders and their promise as therapeutic targets for related diseases.

Obesity Phenotypes, Lifestyle Medicine, and Population Health: Precision Needed Everywhere!

The worldwide prevalence of obesity is a key factor involved in the epidemic proportions reached by chronic societal diseases. A revolution in the study of obesity has been the development of imaging techniques for the measurement of its regional distribution. These imaging studies have consistently reported that individuals with an excess of visceral adipose tissue (VAT) were those characterized by the highest cardiometabolic risk. Excess VAT has also been found to be accompanied by ectopic fat deposition. It is proposed that subcutaneous versus visceral obesity can be considered as two extremes of a continuum of adiposity phenotypes with cardiometabolic risk ranging from low to high. The heterogeneity of obesity phenotypes represents a clinical challenge to the evaluation of cardiometabolic risk associated with a given body mass index (BMI). Simple tools can be used to better appreciate its heterogeneity. Measuring waist circumference is a relevant step to characterize fat distribution. Another important modulator of cardiometabolic risk is cardiorespiratory fitness. Individuals with a high level of cardiorespiratory fitness are characterized by a lower accumulation of VAT compared to those with poor fitness. Diet quality and level of physical activity are also key behaviors that substantially modulate cardiometabolic risk. It is proposed that it is no longer acceptable to assess the health risk of obesity using the BMI alone. In the context of personalized medicine, precision lifestyle medicine should be applied to the field of obesity, which should rather be referred to as 'obesities.'

Promotion of Cardiometabolic Health: A Personal Journey

PURPOSE OF REVIEW: Narrative review of the author's main contributions to the field of cardiovascular health spanning four decades, with a focus on findings related to 1- the pathophysiology of obesity, insulin resistance, type 2 diabetes and cardiovascular disease, and 2- the management/prevention of these conditions. Particular attention is given to the importance of regular physical activity. RECENT FINDINGS: Because behaviors and their physiological consequences are still not measured in clinical practice, it is proposed to systematically assess and target "lifestyle vital signs" (waist circumference, cardiorespiratory fitness, food-based diet quality and level of leisure-time physical activity) in primary care. However, cardiometabolic health of the population will not be substantially improved until our living and economic conditions are permissive to the adoption of healthy behaviors. Closing the gap between primary care and public health should be a priority to address the socioeconomic determinants of cardiometabolic health.

Influence of Obesity, Race and Gender on Radiation Exposure for Epidural Procedures

PURPOSE OF REVIEW

This retrospective, case controlled, comparative evaluation review of radiation exposure during epidural procedures in interventional pain management assessed variations in radiation exposure based on obesity, race, and gender.

RECENT FINDINGS

Numerous publications have shown increasing radiation exposure based on body mass index (BMI). However, the influence of race and gender have not been studied. A recent study assessing radiation exposure for epidural procedures with mandated 2 views, compared to a single view or optional 2 views, showed an increase in exposure time of 21%, with radiation dose increases of 133%. The influence of obesity, has been studied, but potential influence of race, and gender on radiation exposure for epidural procedures has not been studied. The present review shows a prevalence of total obesity with BMI of 30 or above of 50.9%, with a higher prevalence in patients below the age of 45, female gender, and African Americans. Mean fluoroscopy time and dose increased significantly from 6.9 s to 0.925 milligray (mGy) for all epidural procedures for those who are underweight to 10.0 s and 6.7 mGy for those with Class 3 obesity above BMI of 40. However, after adjusting for body mass index, no significant differences were noted in race for both fluoroscopy time and radiation dose across multiple epidural procedures. Fluoroscopy time and radiation dose increased in males in cervical interlaminar and lumbar transforaminal procedures.

Understanding Adipose Tissue Dysfunction

Diseases affecting adipose tissue (AT) function include obesity, lipodystrophy, and lipedema, among others. Both a lack of and excess AT are associated with increased risk for developing diseases including type 2 diabetes mellitus, hypertension, obstructive sleep apnea, and some types of cancer. However, individual risk of developing cardiometabolic and other 'obesity-related' diseases is not entirely determined by fat mass. Rather than excess fat accumulation, AT dysfunction may represent the mechanistic link between obesity and comorbid diseases. There are people who remain metabolically healthy despite obesity, whereas people with normal weight or very low subcutaneous AT mass may develop typically obesity-related diseases. AT dysfunction is characterized by adipocyte hypertrophy, impaired subcutaneous AT expandability (ectopic fat deposition), hypoxia, a variety of stress, inflammatory processes, and the release of proinflammatory, diabetogenic, and atherogenic signals. Genetic and environmental factors might contribute to AT heterogeneity either alone or via interaction with intrinsic biological factors. However, many questions remain regarding the mechanisms of AT dysfunction initiation and whether and how it could be reversed. Do AT signatures define clinically relevant subtypes of obesity? Is the cellular composition of AT associated with variation in obesity phenotypes? What roles do environmental compounds play in the manifestation of AT dysfunction? Answers to these and other questions may explain AT disease mechanisms and help to define strategies for improving AT health. This review focuses on recent advances in our understanding of AT biology.

Alterations in Adipose Tissue and Adipokines in Heterozygous APE1/Ref-1 Deficient Mice

BACKGRUOUND

The role of apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/Ref-1) in adipose tissue remains poorly understood. This study investigates adipose tissue dysfunction in heterozygous APE1/Ref-1 deficiency (APE1/Ref-1+/-) mice, focusing on changes in adipocyte physiology, oxidative stress, adipokine regulation, and adipose tissue distribution.

METHODS

APE1/Ref-1 mRNA and protein levels in white adipose tissue (WAT) were measured in APE1/Ref-1+/- mice, compared to their wild-type (APE1/Ref-1+/+) controls. Oxidative stress was assessed by evaluating reactive oxygen species (ROS) levels. Histological and immunohistochemical analyses were conducted to observe adipocyte size and macrophage infiltration of WAT. Adipokine expression was measured, and micro-magnetic resonance imaging (MRI) was used to quantify abdominal fat volumes.

RESULTS

APE1/Ref-1+/- mice exhibited significant reductions in APE1/Ref-1 mRNA and protein levels in WAT and liver tissue. These mice also showed elevated ROS levels, suggesting a regulatory role for APE1/Ref-1 in oxidative stress in WAT and liver. Histological and immunohistochemical analyses revealed hypertrophic adipocytes and macrophage infiltration in WAT, while Oil Red O staining demonstrated enhanced ectopic fat deposition in the liver of APE1/Ref-1+/- mice. These mice also displayed altered adipokine expression, with decreased adiponectin and increased leptin levels in the WAT, along with corresponding alterations in plasma levels. Despite no significant changes in overall body weight, microMRI assessments demonstrated a significant increase in visceral and subcutaneous abdominal fat volumes in APE1/Ref-1+/- mice.

CONCLUSION

APE1/Ref-1 is crucial in adipokine regulation and mitigating oxidative stress. These findings suggest its involvement in adipose tissue dysfunction, highlighting its potential impact on abdominal fat distribution and its implications for obesity and oxidative stress-related conditions.

Dynapenia-abdominal obesity and mortality risk, is independent effect obscured by age and frailty?:Birjand Longitudinal Aging Study (BLAS)

Background

Abdominal obesity and low muscle strength, known separately as risk factors for mortality, might have a synergistic effect when they co-occur. Dynapenic abdominal obesity (DAO) is a condition defined by the presence of both. However, DAO's independent and combined impact on mortality remains under investigation.

Objective

The objective of the present study was to evaluate the association of dynapenia, abdominal obesity, and dynapenic abdominal obesity with all-cause mortality among community-dwelling older adults.

Methods

This is a longitudinal study with a 5-year follow-up conducted involving 1,354 community-dwelling older adults (≥ 65 years) of the Birjand Longitudinal Aging Study (BLAS). Abdominal obesity and dynapenia were respectively defined based on waist circumference (> 102 cm for men and > 88 cm for women) and grip strength (< 26 kg for men and < 16 kg for women). The sample was divided into four groups: non-dynapenic/non-abdominal obesity (ND/NAO), dynapenic/non-abdominal obesity (D/NAO), non-dynapenic/abdominal obesity (ND/AO), and dynapenic/abdominal obesity (D/AO). The outcome was all-cause mortality registered through four methods: 1- telephone interview with the family of the participants during September 2018 and February 2024, 2- hospital information systems, 3- death registry of the deputy of the Health of Birjand University of Medical Sciences 4- in a subject who died at home or out of hospital death registry was verified by a verbal autopsy performed by a clinician. Univariate and multiple Logistic regression models were used to estimate the risk of all-cause mortality as a function of dynapenia and abdominal obesity in competing events controlled by age, sex, multi-morbidity, and frailty.

Results

The mean age of the study participants was 69.77 ± 7.55 years, and about 703 (51.71%) were female. There was a statistical difference between the alive and the deceased groups in terms of sex, age, multimorbidity, and frailty. Mortality was statistically higher among dynapenic participants (P < 0.001). Unadjusted logistic regression analysis explored the relationship between D/NAO and mortality (OR = 2.18; CI 95% 1.25-3.78). In the adjusted models, no significant relationships were observed. Age and frailty had significant associations with mortality.

Conclusion

While our study found an association between dynapenia without abdominal obesity and increased mortality risk, factors like age and frailty might play a stronger role. These require further investigation to understand the independent effect of dynapenia on mortality fully.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-024-01501-8.

Association between metabolic syndrome and benign prostatic hyperplasia: The underlying molecular connection

Benign prostatic hyperplasia (BPH), a common cause of lower urinary tract symptoms (LUTS), has been recently regarded as a metabolic disease. Metabolic syndrome (MetS) is a constellation of metabolic disarrangements, including insulin resistance, obesity, hypertension, and dyslipidemia, and it has been established that these components of MetS are important contributing factors exacerbating the degree of prostatic enlargement and bladder outlet obstruction among patients with BPH. Clinical and experimental studies demonstrated that many molecules, such as insulin, insulin-like growth factor 1 (IGF-1), androgen and estrogen, and adipokines, are involved in the overlapping pathogenesis of BPH and MetS, indicating that clinicians might be able to simultaneously alleviate or cure two diseases by choosing appropriate medications. This article aims to systematically review the pathophysiological aspect and traditional etiology and pathogenesis of BPH and discuss the intricate association between MetS and BPH from the molecular point of view, in an attempt to provide stronger evidence for better treatment of two diseases.

Hypomethylation at PANDAR promoter progressively induces senescence in adipocyte precursor cells in subjects with obesity and type 2 diabetes

The risk of developing type 2 diabetes (T2D) is heterogeneous among individuals with obesity. Functional decline of adipocyte precursor cells (APCs) and accumulation of senescent cells in the subcutaneous adipose tissue contributes to the progression toward T2D. LncRNAs regulate cell senescence and may be implicated in determining this abnormality in APCs. Here, we report that APCs from individuals with obesity show a gradual increase in multiple senescence markers, which worsens in parallel with the progression from normal glucose tolerance (NGT) to impaired glucose tolerance (IGT) or T2D. Transcriptomic analysis identified PANDAR as the top-ranked lncRNA differentially expressed in APCs from individuals with obesity and T2D and non-obese subjects. Q-PCR confirmed PANDAR up-regulation in APCs from individuals with obesity, at progressively increased levels in those who developed, respectively, IGT and T2D. Bisulfite sequencing and luciferase assays revealed that, in parallel with glucose tolerance deterioration, the -1317 CpG at the PANDAR promoter became hypo-methylated in obesity, resulting in enhanced PANDAR induction by p53. PANDAR silencing in senescent APCs from individuals with obesity and T2D caused repression of senescence programs and cell cycle re-entry. PANDAR transcription in white blood cells (WBCs) mirrored that in APCs. Also, individuals with obesity exhibited rescue of PANDAR transcription in WBCs following bariatric surgery, accompanied by enhanced methylation at the regulatory PANDAR -1317 CpG. In conclusion, PANDAR dysregulation is a newly identified mechanism determining the early senescence of APCs from individuals with obesity, which worsens along the progression toward T2D. In the future, PANDAR targeting may represent a valuable strategy to delay this progression.

Baicalin suppresses macrophage JNK-mediated adipose tissue inflammation to mitigate insulin resistance in obesity

ETHNOPHARMACOLOGICAL RELEVANCE

Radix scutellariae (the root of Scutellaria baicalensis Georgi) is a traditional Chinese medicine (TCM) used to treat a wide range of inflammation-related diseases, such as obesity, diabetes, diabetic kidney disease, and COVID-19-associated inflammatory states in the lung and kidney. Baicalin is the major anti-inflammatory component of Radix scutellariae and has shown the potential to inhibit inflammation in metabolic disorders. In this study, we explored the ability and underlying mechanisms of baicalin to modulate the macrophage to mitigate insulin resistance in obesity.

MATERIALS AND METHODS

Obese mice were administered baicalin (50 mg/kg/day) intraperitoneally for 3 weeks. RAW264.7 and BMDM cells were stimulated with LPS and treated with baicalin for 24 h, while 3T3-L1 and primary white adipocytes were treated with the supernatants from baicalin-treated RAW264.7 cells for 24 h.

RESULTS

The results showed that baicalin significantly improved glucose and insulin tolerance as well as decreased fat and adipose tissue macrophage levels in obese mice. Besides, baicalin significantly reduced serum and adipose tissue IL-1β, TNF-α and IL-6 levels in obese mice, as well as suppressed LPS-induced IL-1β, TNF-α and IL-6 expression and release in macrophages. Furthermore, treatment with the supernatant from baicalin-treated RAW264.7 cells increased the levels of PGC-1α, SIRT1, p-IRS-1 and p-AKT in adipocytes. Moreover, baicalin treatment dramatically downregulated macrophage p-p38, p-JNK, and Ac-p65Lys310 levels while increasing SIRT1 both in vivo and in vitro. Importantly, JNK inhibitor SP600125 blocked most of the effects of baicalin on SIRT1, Ac-p65Lys310 and pro-inflammatory factors in macrophages.

CONCLUSION

Therefore, these results demonstrated for the first time that baicalin exerts its anti-inflammatory effects in obese adipose tissue macrophages mainly through suppressing JNK/SIRT1/p65 signaling. These findings amplified the mechanisms of baicalin and its potential to attenuate insulin resistance.

An optimized pipeline for high-throughput bulk RNA-Seq deconvolution illustrates the impact of obesity and weight loss on cell composition of human adipose tissue

Cellular heterogeneity of human adipose tissue, is linked to the pathophysiology of obesity and may impact the response to energy restriction and changes in fat mass. Here, we provide an optimized pipeline to estimate cellular composition in human abdominal subcutaneous adipose tissue (ASAT) from publicly available bulk RNA-Seq using signature profiles from our previously published full-length single nuclei (sn)RNA-Seq of the same depot. Individuals with obesity had greater proportions of macrophages and lower proportions of adipocyte sub-populations and vascular cells compared with lean individuals. Two months of diet-induced weight loss (DIWL) increased the estimated proportions of macrophages; however, two years of DIWL reduced the estimated proportions of macrophages, thereby suggesting a bi-phasic nature of cellular remodeling of ASAT during weight loss. Our optimized high-throughput pipeline facilitates the assessment of composition changes of highly characterized cell types in large numbers of ASAT samples using low-cost bulk RNA-Seq. Our data reveal novel changes in cellular heterogeneity and its association with cardiometabolic health in humans with obesity and following weight loss.

Obesity-induced chronic low-grade inflammation in adipose tissue: A pathway to Alzheimer's disease

Alzheimer's disease (AD) is a leading cause of cognitive impairment worldwide. Overweight and obesity are strongly associated with comorbidities, such as hypertension, diabetes, and insulin resistance (IR), which contribute substantially to the development of AD and subsequent morbidity and mortality. Adipose tissue (AT) is a highly dynamic organ composed of a diverse array of cell types, which can be classified based on their anatomic localization or cellular composition. The expansion and remodeling of AT in the context of obesity involves immunometabolic and functional shifts steered by the intertwined actions of multiple immune cells and cytokine signaling within AT, which contribute to the development of metabolic disorders, IR, and systemic markers of chronic low-grade inflammation. Chronic low-grade inflammation, a prolonged, low-dose stimulation by specific immunogens that can progress from localized sites and affect multiple organs throughout the body, leads to neurodystrophy, increased apoptosis, and disruption of homeostasis, manifesting as brain atrophy and AD-related pathology. In this review, we sought to elucidate the mechanisms by which AT contributes to the onset and progression of AD in obesity through the mediation of chronic low-grade inflammation, particularly focusing on the roles of adipokines and AT-resident immune cells.

The individual response to antibiotics and diet - insights into gut microbial resilience and host metabolism

Antibiotic use disrupts microbial composition and activity in humans, but whether this disruption in turn affects host metabolic health is unclear. Cohort studies show associations between antibiotic use and an increased risk of developing obesity and type 2 diabetes mellitus. Here, we review available clinical trials and show the disruptive effect of antibiotic use on the gut microbiome in humans, as well as its impact on bile acid metabolism and microbial metabolites such as short-chain fatty acids. Placebo-controlled human studies do not show a consistent effect of antibiotic use on body weight and insulin sensitivity at a population level, but rather an individual-specific or subgroup-specific response. This response to antibiotic use is affected by the resistance and resilience of the gut microbiome, factors that determine the extent of disruption and the speed of recovery afterwards. Nutritional strategies to improve the composition and functionality of the gut microbiome, as well as its recovery after antibiotic use (for instance, with prebiotics), require a personalized approach to increase their efficacy. Improved insights into key factors that influence the individual-specific response to antibiotics and dietary intervention may lead to better efficacy in reversing or preventing antibiotic-induced microbial dysbiosis as well as strategies for preventing cardiometabolic diseases.

Adiponectin and TNFα in relation to glucometabolic control in patients with type 2 diabetes mellitus

Background

The correlation of adiponectin and serum tumor necrosis factor alpha (TNFα) with glucometabolic parameters in diabetes mellitus (DM) needs further studies. We aimed in this study to evaluate the relationship between adiponectin and TNFα with glucometabolic parameters in patients with type 2 DM (T2DM).

Methods

We conducted a cross-sectional study in the Department of Physiology, College of Medicine, King Saud University, Saudi Arabia. The sample size was 117 from the diabetes clinic of King Abdul-Aziz University hospital through the convenience sampling technique. Subjects were grouped into control (healthy) subjects (53) with no chronic diseases and the diabetic group (64) with confirmed T2DM. Socio-demographic data were collected along with the serum blood sample to analyze the variables.

Results

Adiponectin was significantly high in healthy subjects compared to the diabetic group (control: 14.4 ± 4.3, T2DM: 11.0 ± 4.1, P = 0.000), while TNFα was higher in the T2DM group (7.8 ± 2.7) than in the control group (6.6 ± 2.9, P = 0.024). TNFα was negatively correlated with adiponectin in the control group (-0.279) and in diabetic subjects (-0.311) and positively correlated with HbA1c in the diabetic group (0.319) and triglycerides (0.252). Adiponectin was positively correlated with HDL in the control group (0.252) and in diabetic subjects (0.326). There was an inverse correlation between TNFα and adiponectin.

Conclusion

Adiponectin is higher in healthy subjects than in diabetic patients, while TNFα is higher in diabetic patients. In addition, adiponectin is positively correlated with HDL in healthy as well as diabetic patients. TNFα is positively correlated with HbA1c and triglycerides.

Myeloid-derived miR-6236 potentiates adipocyte insulin signaling and prevents hyperglycemia during obesity

Adipose tissue macrophages (ATMs) influence obesity-associated metabolic dysfunction, but the mechanisms by which they do so are not well understood. We show that miR-6236 is a bona fide miRNA that is secreted by ATMs during obesity. Global or myeloid cell-specific deletion of miR-6236 aggravates obesity-associated adipose tissue insulin resistance, hyperglycemia, hyperinsulinemia, and hyperlipidemia. miR-6236 augments adipocyte insulin sensitivity by inhibiting translation of negative regulators of insulin signaling, including PTEN. The human genome harbors a miR-6236 homolog that is highly expressed in the serum and adipose tissue of obese people. hsa-MIR-6236 expression negatively correlates with hyperglycemia and glucose intolerance, and positively correlates with insulin sensitivity. Together, our findings establish miR-6236 as an ATM-secreted miRNA that potentiates adipocyte insulin signaling and protects against metabolic dysfunction during obesity.

Insights into the Role of Glutathione Peroxidase 3 in Non-Neoplastic Diseases

Reactive oxygen species (ROSs) are byproducts of normal cellular metabolism and play pivotal roles in various physiological processes. Disruptions in the balance between ROS levels and the body's antioxidant defenses can lead to the development of numerous diseases. Glutathione peroxidase 3 (GPX3), a key component of the body's antioxidant system, is an oxidoreductase enzyme. GPX3 mitigates oxidative damage by catalyzing the conversion of hydrogen peroxide into water. Beyond its antioxidant function, GPX3 is vital in regulating metabolism, modulating cell growth, inducing apoptosis and facilitating signal transduction. It also serves as a significant tumor suppressor in various cancers. Recent studies have revealed aberrant expression of GPX3 in several non-neoplastic diseases, associating it with multiple pathological processes. This review synthesizes the current understanding of GPX3 expression and regulation, highlighting its extensive roles in noncancerous diseases. Additionally, this paper evaluates the potential of GPX3 as a diagnostic biomarker and explores emerging therapeutic strategies targeting this enzyme, offering potential avenues for future clinical treatment of non-neoplastic conditions.

'Beyond the Scale': A Qualitative Exploration of the Impact of Weight Stigma Experienced by Patients With Obesity in General Practice

OBJECTIVE

Obesity is a complex, chronic, relapsing disease that requires an individualised approach to treatment. However, weight stigma (WS) experienced in healthcare settings poses a significant barrier to achieving person-centred care for obesity. Understanding the experiences of people living with obesity (PwO) can inform interventions to reduce WS and optimise patient outcomes. This study explores how patients with obesity perceive WS in general practice settings; its impact on their psychological well-being and health behaviours, and the patients suggestions for mitigating it.

METHODS

In-depth semistructured interviews were conducted with 11 PwO who had experienced WS in general practice settings in Ireland. The interviews were conducted online via Zoom between May and August 2023; interviews lasted between 31 and 63 min (M = 34.36 min). Interviews were audio-recorded, transcribed verbatim and analysed using inductive reflexive thematic analysis.

RESULTS

Three overarching themes specific to participants' experience of WS in general practice were generated: (1) shame, blame and 'failure'; (2) eat less, move more-the go-to treatment; (3) worthiness tied to compliance. A fourth theme: (4) the desire for a considered approach, outlines the participants' suggestions for reducing WS by improving the quality of patient-provider interactions in general practice.

CONCLUSION

The findings call for a paradigm shift in the management of obesity in general practice: emphasising training for GPs in weight-sensitive communication and promoting respectful, collaborative, and individualised care to reduce WS and improve outcomes for people with obesity.

PATIENT OR PUBLIC CONTRIBUTION

PPI collaborators played an active and equal role in shaping the research, contributing to the development of the research questions, refining the interview schedule, identifying key themes in the data, and granting final approval to the submitted and published version of the study.

Plasma acylcarnitines and amino acids in dyslipidemia: An integrated metabolomics and machine learning approach

Purpose

The Discovery of underlying intermediates associated with the development of dyslipidemia results in a better understanding of pathophysiology of dyslipidemia and their modification will be a promising preventive and therapeutic strategy for the management of dyslipidemia.

Methods

The entire dataset was selected from the Surveillance of Risk Factors of Noncommunicable Diseases (NCDs) in 30 provinces of Iran (STEPs 2016 Country report in Iran) that included 1200 subjects and was stratified into four binary classes with normal and abnormal cases based on their levels of triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and non-HDL-C.Plasma concentrations of 20 amino acids and 30 acylcarnitines in each class of dyslipidemia were evaluated using Tandem mass spectrometry. Then, these attributes, along with baseline characteristics data, were used to check whether machine learning (ML) algorithms could classify cases and controls.

Results

Our ML framework accurately predicts TG binary classes. Among the models tested, the SVM model stood out, performing slightly better with an AUC of 0.81 and a standard deviation of test accuracy at 0.04. Consequently, it was chosen as the optimal model for TG classification. Moreover, the findings showed that alanine, phenylalanine, methionine, C3, C14:2, and C16 had great power in differentiating patients with high TG from normal TG controls. Conclusions: The comprehensive output of this work, along with sex-specific attributes, will improve our understanding of the underlying intermediates involved in dyslipidemia.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-024-01384-9.

Enhanced Metabolic Effects of Fish Oil When Combined with Vitamin D in Diet-Induced Obese Male Mice

Vitamin D (vit D) and fish oil (FO) both offer unique health benefits, however, their combined effects have not been evaluated in obesity and nonalcoholic fatty liver disease (NAFLD). Hence, we hypothesized that vit D and FO supplementation would have additive effects in reducing obesity-associated inflammation and NAFLD. Male C57BL6 mice were split into four groups and fed a high fat (HF) diet supplemented with a low (HF; +200 IU vit D) or high dose of vitamin D (HF + D; +1000 IU vit D); combination of vit D and FO (HF-FO; +1000 IU vit D); or only FO (HF-FO; +200 IU vit D) for 12 weeks. We measured body weight, food intake, glucose tolerance, and harvested epididymal fat pad and liver for gene expression analyses. Adiposity was reduced in groups supplemented with both FO and vit D. Glucose clearance was higher in FO-supplemented groups compared to mice fed HF. In adipose tissue, markers of fatty acid synthesis and oxidation were comparable in groups that received vit D and FO individually in comparison to HF. However, the vit D and FO group had significantly lower fatty acid synthesis and higher oxidation compared to the other groups. Vit D and FO also significantly improved fatty acid oxidation, despite similar fatty acid synthesis among the four groups in liver. Even though we did not find additive effects of vit D and FO, our data provide evidence that FO reduces markers of obesity in the presence of adequate levels of vit D.

Association between serum ferritin level and lipid profile among diabetic patients: A retrospective cohort study

High serum ferritin (SF) levels have been linked to obesity, metabolic syndrome, atherosclerosis, diabetes, dyslipidemia, and cancer. This study aimed to investigate the association between SF and dyslipidemia in adults diagnosed with diabetes mellitus. This cross-sectional study retrospectively analyzed the electronic medical records of eligible patients from 3 primary locations in Saudi Arabia namely - Abha, Khamis Mushyt, and Jeddah - from 2010 to 2020. The study included adult patients aged 18 years or older who were diagnosed with diabetes mellitus and identified with an HbA1c level of ≥6.5. This study involved 3674 participants, with males accounting for 26.6% of the total. The mean age of the studied population was 48.0 ± 18.4 years. The median [interquartile range] of SF among males was higher than females, however, this difference was not statistically significant (60.0 [23.4-125.8] vs 55.4 [24.0-113.4], P = 0.204). On the other hand, age and region were significantly associated with SF (P = .032 and 0.035). SF had a significant positive correlation with cholesterol (r = 0.081, P < .001), low-density lipoprotein cholesterol (r = .087, P < .001), and triglycerides (r = 0.068, P < .001) and negative correlation with high-density lipoprotein cholesterol (r = -0.13, P < .001). Multivariate analysis revealed that age, sex, residence, and HbA1c were significantly affecting the lipid profile. Clinicians should consider including SF testing as part of the comprehensive evaluation of patients with diabetes and dyslipidemia.

Inversion of the Warburg Effect: Unraveling the Metabolic Nexus between Obesity and Cancer

Obesity is a well-established risk factor for cancer, significantly impacting both cancer incidence and mortality. However, the intricate molecular mechanisms connecting adipose tissue to cancer cell metabolism are not fully understood. This Review explores the historical context of tumor energy metabolism research, tracing its origins to Otto Warburg's pioneering work in 1920. Warburg's discovery of the "Warburg effect", wherein cancer cells prefer anaerobic glycolysis even in the presence of oxygen, laid the foundation for understanding cancer metabolism. Building upon this foundation, the "reverse Warburg effect" emerged in 2009, elucidating the role of aerobic glycolysis in cancer-associated fibroblasts (CAFs) and its contribution to lactate accumulation in the tumor microenvironment, subsequently serving as a metabolic substrate for cancer cells. In contrast, within high-adiposity contexts, cancer cells exhibit a unique metabolic shift termed the "inversion of the Warburg effect". This phenomenon, distinct from the stromal-dependent reverse Warburg effect, relies on increased nutrient abundance in obesity environments, leading to the generation of glucose from lactate as a metabolic substrate. This Review underscores the heightened tumor proliferation and aggressiveness associated with obesity, introducing the "inversion of the Warburg effect" as a novel mechanism rooted in the altered metabolic landscape within an obese milieu. The insights presented here open promising avenues for therapeutic exploration, offering fresh perspectives and opportunities for the development of innovative cancer treatment strategies.

Amelioration of obesity induction by a high-fat diet and related inflammation by Phasa fish (Setipinna phasa) oil in BALB/c mice

We have extracted and characterized Phasa fish (Setipinna phasa) oil for the first time to evaluate the anti-obesity and related anti-inflammatory effects on obese mice. Inbred male albino BALB/c mice were segregated into three categories: control (C), Obese control group (OC), and Phasa fish oil treated group (TX). To establish the potentiality of Setipinna phasa oil for its anti-obesity and anti-inflammatory properties, it was extracted and characterized using GC-MS method. To evaluate the anti-obesity effect, different parameters were considered, such as body weight, lipid composition, obesity, and obesity associated inflammation. The physicochemical characteristics of Phasa fish oil revealed that the oil quality was good because acid value, peroxide value, p-anisidine value, Totox value, refractive index, and saponification value were within the standard value range. The GC-MS study explored the presence of fatty acids beneficial to health such as Hexadec-9-enoic acid; Octadec-11-enoic acid; EPA, DHA, Methyl Linolenate, etc. The application of Setipinna phasa oil on the treated mice group acutely lowered body weight and serum lipid profile compared to the obese group. In connection with this, leptin, FAS, and pro-inflammatory cytokines TNF-α genes expression were downregulated in the treated group compared to the obese group. The Phasa oil treated group had an elevated expression of PPAR-α, adiponectin, LPL gene, and anti-inflammatory markers IL-10 and IL-1Ra compared to the obese group. This study suggests that Phasa fish oil, enriched with essential fatty acid, might be used as an anti-obesity and anti-inflammatory supplement.

Normal weight obesity is associated with lower AFC and adverse IVF outcomes

Background

Body weight could be classified into underweight, normal weight and overweight according to percentage of body fat (%BF), and normal weight obesity (NWO) is defined as a normal BMI but a high %BF. While the impact of NWO in women fecundity remain unknow. Therefore, this study aimed to investigate the associations between %BF and reproductive outcomes among in vitro fertilization (IVF) women with normal BMI.

Methods

A total of 469 women were included in this study and were classified into low %BF, normal %BF and high %BF according to previous study. Multivariate generalized regression models were employed to evaluate the associations of %BF with ovarian reserve parameters, IVF outcomes and early pregnancy outcomes. We further run sensitivity analyses by restricted the analysis to young women and those only with tubal factor, respectively.

Results

About 32.2% of normal BMI women were misclassified according %BF, with 16.4% of them were low %BF and 15.8% were high %BF. The high %BF group had significantly lower antral follicle count (AFC) than normal %BF groups, and the AFC showed a tendency of decrease as %BF increased. In sensitivity analysis in young women, high %BF group also had significantly lower number of good-quality embryos when compared to normal %BF groups. The results expanded to all IVF outcomes when analysis restricted to tubal factor women.

Conclusion

In summary, misclassifications of body weight status based on BMI are common according to %BF, and NWO is associated with adverse reproductive outcomes.

Association of Dietary Protein Sources and Their Adequacy, Body Composition and Risk of Sarcopenic Obesity in South Korean Populations: A Cross-Sectional Study

Dietary protein sources and protein adequacy are crucial modulators of muscle quality and body composition. We investigated the association between dietary protein sources (and their adequacy) and body composition and the risk of sarcopenic obesity (SO) in South Korean populations. The participants (n = 1967) were classified into SO, obese, sarcopenia, and normal groups. A cross-sectional survey was conducted using the KS-15 questionnaire, short-form food frequency questionnaire, and anthropometric measurements. The percentage of body fat (male: 35.36 ± 0.51%; female: 44.14 ± 0.36%) was significantly high, while appendicular skeletal muscle (ASM; male: 36.39 ± 0.30%, female: 30.32 ± 0.19%) was low in the SO group. Beef and pork consumption was negatively associated with ASM (%) but positively associated with body fat (%) in the normal group and positively associated with ASM (kg/m2: beta = 0.002, p = 0.02) and BFM (kg: beta = 0.012, p = 0.03) in the SO group, respectively. The highest quintile (Q5: 173.6 g/day) showed a decreased risk of SO prevalence (AORs: 0.46, CI: 0.22-0.94) compared with that in the lowest quintile (Q1: 21.6 g/day) among the people with inadequacy protein intake. Daily poultry and egg intake was positively linked with body composition in the participants with SO, while red meat showed a negative effect on imbalanced body composition in participants in the normal and SO groups. Furthermore, a lower intake of poultry and eggs was strongly associated with SO prevalence in people who consumed inadequate amounts of daily dietary protein.

Phenotyping obesity: A focus on metabolically healthy obesity and metabolically unhealthy normal weight

Over the past 4 decades, research has shown that having a normal body weight does not automatically imply preserved metabolic health and a considerable number of lean individuals harbour metabolic abnormalities typically associated with obesity. Conversely, excess adiposity does not always equate with an abnormal metabolic profile. In fact, evidence exists for the presence of a metabolically unhealthy normal weight (MUHNW) and a metabolically healthy obese (MHO) phenotype. It has become increasingly recognised that different fat depots exert different effects on the metabolic profile of each individual by virtue of their location, structure and function, giving rise to these different body composition phenotypes. Furthermore, other factors have been implicated in the aetiopathogenesis of the body composition phenotypes, including genetics, ethnicity, age and lifestyle/behavioural factors. Even though to date both MHO and MUHNW have been widely investigated and documented in the literature, studies report different outcomes on long-term cardiometabolic morbidity and mortality. Future large-scale, observational and population-based studies are required for better profiling of these phenotypes as well as to further elucidate the pathophysiological role of the adipocyte in the onset of metabolic disorders to allow for better risk stratification and a personalised treatment paradigm.

The Role of Adipokines in Tumor Progression and Its Association with Obesity

Obesity is a well-established risk factor for various malignancies and emerging evidence suggests that adipokines play a pivotal role in linking excess adiposity to tumorigenesis. Adipokines are bioactive molecules secreted by adipose tissue and their altered expression in obesity contributes to a pro-inflammatory, pro-angiogenic, and growth-promoting microenvironment conducive to tumorigenesis. Leptin, a key adipokine, activates survival and proliferative signaling pathways whereas adiponectin exhibits tumor-suppressive effects by inducing apoptosis and cell cycle arrest. Visfatin has also been documented to promote tumor growth, angiogenesis, migration, and invasion. Moreover, emerging studies suggest that adipokines, such as resistin, apelin, and chemerin, which are overexpressed in obesity, may also possess oncogenic functions. Despite advancements in our understanding of the roles of individual adipokines in cancer, the intricate interplay and crosstalk between adipokines, tumor cells, and the tumor microenvironment remain complex and multifaceted. This review highlights the evolving knowledge of how adipokines contribute to obesity-related tumorigenesis, shedding light on the potential of targeting adipokine signaling pathways as a novel therapeutic approach for obesity-associated cancers. Further research on the specific mechanisms and interactions between adipokines and tumor cells is crucial for a comprehensive understanding of obesity-associated cancer pathogenesis.

Endoplasmic Reticulum Stress and Its Impact on Adipogenesis: Molecular Mechanisms Implicated

Endoplasmic reticulum (ER) stress plays a pivotal role in adipogenesis, which encompasses the differentiation of adipocytes and lipid accumulation. Sustained ER stress has the potential to disrupt the signaling of the unfolded protein response (UPR), thereby influencing adipogenesis. This comprehensive review illuminates the molecular mechanisms that underpin the interplay between ER stress and adipogenesis. We delve into the dysregulation of UPR pathways, namely, IRE1-XBP1, PERK and ATF6 in relation to adipocyte differentiation, lipid metabolism, and tissue inflammation. Moreover, we scrutinize how ER stress impacts key adipogenic transcription factors such as proliferator-activated receptor γ (PPARγ) and CCAAT-enhancer-binding proteins (C/EBPs) along with their interaction with other signaling pathways. The cellular ramifications include alterations in lipid metabolism, dysregulation of adipokines, and aged adipose tissue inflammation. We also discuss the potential roles the molecular chaperones cyclophilin A and cyclophilin B play in adipogenesis. By shedding light on the intricate relationship between ER stress and adipogenesis, this review paves the way for devising innovative therapeutic interventions.

In vitro studies of the renin-angiotensin system in human adipose tissue/adipocytes and possible relationship to SARS-CoV-2: a scoping review

The renin-angiotensin system (RAS) operates within adipose tissue. Obesity-related changes can affect adipose RAS, predisposing to hypertension, type 2 diabetes, and possibly severe COVID-19. We evaluated the in vitro research on human adipose RAS and identified gaps in the literature. Medline (Ovid), Embase (Ovid), Web of Science, Scopus, and 1findr were searched to identify relevant studies. Fifty primary studies met our inclusion criteria for analysis. Expression of RAS components (n = 14), role in differentiation (n = 14), association with inflammation (n = 15) or blood pressure (n = 7) were investigated. We found (1) obesity-related changes in RAS were frequently studied (30%); (2) an upswing of articles investigating adipose ACE-2 expression since the COVID-19 pandemic; (3) a paucity of papers on AT2R and Ang (1-7)/MasR which counterbalance Ang II/ART1; (4) weight loss lowered adipose ACE-2 mRNA expression; and (5) angiotensin receptor blockers (ARBs) reduced deleterious effects of angiotensin II. Overall, these studies link Ang II/ATR1 signalling to impaired adipogenesis and a pro-inflammatory dysfunctional adipose tissue, with ATR1 blockade limiting these responses. ACE-2 may mitigate Ang II effects by converting it to Ang(1-7) which binds MasR. More work is needed to understand adipose RAS in various pathologic states such as obesity and COVID-19 infection.T.

Equity in Obesity Review

Obesity disproportionately affects racial and ethnic minoritized populations and those of lower socioeconomic status. Similarly, disparities exist in the development of its downstream consequences, such as type 2 diabetes and hypertension. The causes of these disparities are multifactorial and are influenced by structural factors such as segregation and healthcare access, and individual-level factors such as weight stigma. Interventions to decrease disparities in obesity should consider macro-level, community, and individual-level factors that might reduce disparities and improve equity in obesity care. Clinicians must also recognize the chronic nature of obesity, and how bias and stigma may impact patient care.

Splicing across adipocyte differentiation is highly dynamic and impacted by metabolic phenotype

Adipose tissue dysfunction underlies many of the metabolic complications associated with obesity. A better understanding of the gene regulation differences present in metabolically unhealthy adipose tissue can provide insights into the mechanisms underlying adipose tissue dysfunction. Here, we used RNA-seq data collected from a differentiation time course of lean, obese, and obese with type 2 diabetes (T2D) individuals to characterize the role of alterative splicing in adipocyte differentiation and function. We found that splicing was highly dynamic across adipocyte differentiation in all three cohorts, and that the dynamics of splicing were significantly impacted by metabolic phenotype. We also found that there was very little overlap between genes that were differentially spliced in adipocyte differentiation and those that were differentially expressed, positioning alternative splicing as a largely independent gene regulatory mechanism whose impact would be missed when looking at gene expression changes alone. To assess the impact of alternative splicing across adipocyte differentiation on genetic risk for metabolic diseases, we integrated the differential splicing results generated here with genome-wide association study results for body mass index and T2D, and found that variants associated with T2D were enriched in regions that were differentially spliced in early differentiation. These findings provide insight into the role of alternative splicing in adipocyte differentiation and can serve as a resource to guide future variant-to-function studies.

Omega-3 PUFAs prevent bone impairment and bone marrow adiposity in mouse model of obesity

Obesity adversely affects bone and fat metabolism in mice and humans. Omega-3 polyunsaturated fatty acids (omega-3 PUFAs) have been shown to improve glucose metabolism and bone homeostasis in obesity. However, the impact of omega-3 PUFAs on bone marrow adipose tissue (BMAT) and bone marrow stromal cell (BMSC) metabolism has not been intensively studied yet. In the present study we demonstrated that omega-3 PUFA supplementation in high fat diet (HFD + F) improved bone parameters, mechanical properties along with decreased BMAT in obese mice when compared to the HFD group. Primary BMSCs isolated from HFD + F mice showed decreased adipocyte and higher osteoblast differentiation with lower senescent phenotype along with decreased osteoclast formation suggesting improved bone marrow microenvironment promoting bone formation in mice. Thus, our study highlights the beneficial effects of omega-3 PUFA-enriched diet on bone and cellular metabolism and its potential use in the treatment of metabolic bone diseases.

Increased cholesterol uptake is associated with the altered gene expression in white adipose tissue of ApoE-/- mice fed a high-fat high-cholesterol diet

Apolipoprotein E knock out (ApoE-/-) mice, the widely used model for atherosclerosis, exhibits anti-obesity characteristics due to the impaired lipoprotein internalization. Since excessive accumulation of triglycerides and cholesterol in white adipose tissue (WAT) is shown to increase the risk of metabolic diseases, we investigated the effects of dietary high-fat high-cholesterol (HFHC) on gene expression profile and the possible role of cholesterol accumulation in WAT of ApoE-/- mice. Control (CON) and HFHC diets were provided to wild-type mice (WC, WH) and ApoE-/- mice (EC, EH) for 10 weeks. Although body and WAT weights were lower in the ApoE-/- group compared to the wild-type group, increases in cholesterol and lipid peroxides in WAT were only observed in the ApoE-/- group. Transcriptome analysis revealed 3660 and 839 differentially expressed genes (DEGs) in the EC/WC and EH/WH comparison, respectively. "Thermogenesis" and "Oxidative phosphorylation" KEGG pathways were found in the EC/WC comparison, but not in the EH/WH comparison. We identified 142 and 2585 DEGs in the WH/WC and EH/EC comparison respectively, indicating a stronger effect of HFHC on WAT of ApoE-/- mice. Gene ontology analysis of DEGs revealed the association of DEGs with "Regulation of inflammatory response" term, in the EH/EC comparison, but not in the WH/WC comparison. Especially, genes encoding scavenger receptors and toll-like receptors were associated with cholesterol and lipid peroxide levels in WAT of ApoE-/- mice, but not in wild-type mice. In conclusion, changes in gene expression profile of WAT were more pronounced in ApoE-/- mice compared to wild-type mice in response to HFHC, and these altered genes were related to inflammatory response. These data suggest that increased cholesterol accumulation in WAT by dietary HFHC may play a pivotal role in the regulation of gene expression in ApoE-/- mice.

Tibetan tea reduces obesity brought on by a high-fat diet and modulates gut flora in mice

It has been shown that Tibetan tea (TT) inhibits obesity and controls lipid metabolism. The fundamental processes by which TT prevents obesity are yet entirely unknown. Consequently, this research aimed to ascertain if TT may prevent obesity by modifying the gut flora. Our research demonstrated that TT prevented mice from gaining weight and accumulating fat due to the high-fat diet (HFD), decreased levels of blood total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C), and raised levels of high-density lipoprotein cholesterol (HDL-C). Adipogenesis-related genes such as acetyl-Coenzyme A carboxylase 1 (ACC1, LOC107476), fatty acid synthase (Fas, LOC14104), sterol regulatory element-binding protein-1c (SREBP-1c, LOC20787), CCAAT/enhancer-binding protein α (C/EBPα, LOC12606), stearoyl-CoA desaturase 1 (SCD1, LOC20249), and peroxisome proliferator-activated receptor γ (PPARγ, LOC19016) had their expression downregulated by lowering the Firmicutes/Bacteroidetes (F/B) ratio and controlling the number of certain gut bacteria. TT also alleviated HFD-induced abnormalities of the gut microbiota. The Muribaculaceae, Lachnospiraceae NK4A136_group, Alistipes, and Odoribacter families were identified as the major beneficial gut microorganisms using Spearman's correlation analysis. Fecal microbiota transplantation (FMT) demonstrated that TT's anti-obesity and gut microbiota-modulating benefits might be transmitted to mice on an HFD, demonstrating that one of TT's targets for preventing obesity is the gut microbiota. TT also increased the amount of short-chain fatty acids (SCFAs) in the feces, including acetic, propionic, and butyric acids. These results indicate the possible development of TT as a prebiotic to combat obesity and associated disorders. These results suggest that TT may act as a prebiotic against obesity and its associated diseases.

Obesity and Peripheral Artery Disease: Current Evidence and Controversies

PURPOSE OF REVIEW

Obesity is a significant public health problem and a major risk factor for the development and progression of atherosclerosis and its cardiovascular manifestations. Lower extremity peripheral artery disease (PAD) affects 3%-10% of the Western population and, if left untreated, can lead to devastating outcomes with both an increased risk of morbidity and mortality. Interestingly, the association between obesity and PAD remains debatable. Whereas it is well known that PAD and obesity frequently overlap in the same patients, many studies have demonstrated a negative association between obesity and PAD and a protective effect of obesity on disease development and progression, a phenomenon described as the "obesity paradox." Possible mechanisms for this paradox may include genetic background, as assessed by mendelian randomization studies, adipose tissue dysfunction, and body fat distribution rather than adiposity, while other factors, such as sex, ethnicity, sarcopenia in the elderly population, or aggressive treatment of co-existing metabolic conditions in individuals with obesity compared to those with normal weight, could have some impact as well.

RECENT RINDINGS

Few reviews and meta-analyses examining systematically the relationship between obesity and PAD exist. The impact of PAD development due to the presence of obesity remains largely controversial. However, the most current evidence, backed by a recent meta-analysis, suggests a potential protective role of a higher body mass index on PAD-related complications and mortality. In this review, we discuss the association between obesity and PAD development, progression, and management, and the potential pathophysiologic mechanisms linking the two diseases.

Obesity and hidradenitis suppurativa: targeting meta-inflammation for therapeutic gain

Hidradenitis suppurativa (HS) is a chronic, inflammatory condition of the pilosebaceous unit. The typical patient with HS is characterized as someone with obesity, who smokes and who has nodules, abscesses and/or draining tunnels predominantly distributed in intertriginous skin. It has been established that lifestyle and genetic factors are the main pathophysiological drivers of HS. In this critical review, we explore the interrelatedness of meta-inflammation, obesity and HS and discuss if and how this relationship may be manipulated for a therapeutic end.

Supplementation with spinach-derived thylakoid augments the benefits of high intensity training on adipokines, insulin resistance and lipid profiles in males with obesity

Introduction

This study investigated the effects of 12 weeks of high-intensity functional training (HIFT) combined with spinach-derived thylakoid supplementation on some selected Adipokines and insulin resistance in males with obesity.

Method

Sixty-eight participants (mean age: 27.6 ± 8.4 yrs.; mean height: 168.4 ± 2.6 cm; mean weight: 95.7 ± 3.8 kg, mean BMI: 32.6 ± 2.6 kg/m2) were randomly divided into four groups of 17 per group: Control group (CG), Supplement group (SG), Training group (TG), and Training + supplement group (TSG). Following baseline measurements, the two training groups (TG and TSG) started the 12 weeks of exercise training program (3 sessions per week). A total of 36 sessions lasting up to 60 min were included in the HIFT program using the CrossFit program. The eligible participants received 5 g/day of thylakoid-rich spinach extract or matching placebo as 5 g/day of raw corn starch (one sachet, 30 min before lunch) for 12 weeks. Baseline assessments were obtained 48 hours before the start of the training protocols and 48 hours after the last training session in all groups.

Results

There were significant interactions (p<0.001 for all) between exercise and time for adiponectin (ES:0.48), leptin (ES:0.46), resistin (ES:0.3), omentin (ES:0.65), vaspin (ES:0.46), visfatin (ES:0.62), apelin (ES:0.42), RBP4 (ES:0.63), chemrin (0.36) and semaphorin3c (ES: 0.5). Plasma levels of semaphorin3c were significantly correlated (p<0.05) with body weight (r= 0.57), BMI (r= 0.43), FFM (r= -0.612), FAT (r= 0.768), VO2peak (r=-0.53), insulin (r= 0.756), glucose (r= 0.623), and HOMA-IR (r= 0.727). There were also significant group differences in insulin (ES: 0.77), glucose (ES: 0.21), and HOM-IR (ES: 0.44) (p<0.05).

Discussion

Our findings indicate that 12 weeks of HIFT supplemented with spinach-derived thylakoid reduced levels of leptin, resistin, vaspin, visfatin, apelin, RBP4, chemrin, semaphorin3c and insulin resistance while increasing adiponectin and omentin levels in men with obesity.

Plasma lipid metabolites as potential biomarkers for identifying individuals at risk of obesity-induced metabolic complications

Lipidomics studies have indicated an association between obesity and lipid metabolism dysfunction. This study aimed to evaluate and compare cardiometabolic risk factors, and the lipidomic profile in adults and older people. A cross-sectional study was conducted with 72 individuals, divided into two sex and age-matched groups: obese (body mass index-BMI ≥ 30 kg/m2; n = 36) and non-obese (BMI < 30 kg/m2; n = 36). The lipidomic profiles were evaluated in plasma using 1H nuclear magnetic resonance (1H-NMR) spectroscopy. Obese individuals had higher waist circumference (p < 0.001), visceral adiposity index (p = 0.029), homeostatic model assessment insulin resistance (HOMA-IR) (p = 0.010), and triacylglycerols (TAG) levels (p = 0.018). 1H-NMR analysis identified higher amounts of saturated lipid metabolite fragments, lower levels of unsaturated lipids, and some phosphatidylcholine species in the obese group. Two powerful machine learning (ML) models-k-nearest neighbors (kNN) and XGBoost (XGB) were employed to characterize the lipidomic profile of obese individuals. The results revealed metabolic alterations associated with obesity in the NMR signals. The models achieved high accuracy of 86% and 81%, respectively. The feature importance analysis identified signal at 1.50-1.60 ppm (-CO-CH2-CH2-, Cholesterol and fatty acid in TAG, Phospholipids) to have the highest importance in the two models.

The role of extracellular vesicle-derived miRNAs in adipose tissue function and metabolic health

Extracellular vesicles (EVs) are nanometer size lipid particles that are released from virtually every cell type. Recent studies have shown that miRNAs carried by EVs play important roles in intercellular and interorgan communication. In the context of obesity and insulin resistance, EV-derived miRNAs functionally bridge major metabolic organs, including the adipose tissue, skeletal muscle, liver, and pancreas, to regulate insulin secretion and signaling. As a result, many of these EV-derived miRNAs have been proposed as potential disease biomarkers and/or therapeutic agents. However, the field's knowledge of EV miRNA-mediated regulation of mammalian metabolism is still in its infancy. Here, we review the evidence indicating that EV-derived miRNAs provide cell-to-cell and organ-to-organ communication to support metabolic health, highlight the potential medical relevance of these discoveries, and discuss the most important knowledge gaps and future directions for this field.

Adipokines regulate mesenchymal stem cell osteogenic differentiation

Mesenchymal stem cells (MSCs) can differentiate into various tissue cell types including bone, adipose, cartilage, and muscle. Among those, osteogenic differentiation of MSCs has been widely explored in many bone tissue engineering studies. Moreover, the conditions and methods of inducing osteogenic differentiation of MSCs are continuously advancing. Recently, with the gradual recognition of adipokines, the research on their involvement in different pathophysiological processes of the body is also deepening including lipid metabolism, inflammation, immune regulation, energy disorders, and bone homeostasis. At the same time, the role of adipokines in the osteogenic differentiation of MSCs has been gradually described more completely. Therefore, this paper reviewed the evidence of the role of adipokines in the osteogenic differentiation of MSCs, emphasizing bone formation and bone regeneration.

Physiopathological mechanisms related to inflammation in obesity and type 2 diabetes mellitus

Overweight, obesity, and type 2 diabetes mellitus pose global health problems that are ever-increasing. A chronic low-grade inflammatory status and the presence of various pro-inflammatory markers either in circulation or within dysfunctional metabolic tissues are well established. The presence of these factors can, to some extent, predict disease development and progression. A central role is played by the presence of dysfunctional adipose tissue, liver dysfunction, and skeletal muscle dysfunction, which collectively contribute to the increased circulatory levels of proinflammatory factors. Weight loss and classical metabolic interventions achieve a decrease in many of these factors' circulating levels, implying that a better understanding of the processes or even the modulation of inflammation may alleviate these diseases. This review suggests that inflammation plays a significant role in the development and progression of these conditions and that measuring inflammatory markers may be useful for assessing disease risk and development of future treatment methods.

State of art on the mechanisms of laparoscopic sleeve gastrectomy in treating type 2 diabetes mellitus

Obesity and type-2 diabetes mellitus (T2DM) are metabolic disorders. Obesity increases the risk of T2DM, and as obesity is becoming increasingly common, more individuals suffer from T2DM, which poses a considerable burden on health systems. Traditionally, pharmaceutical therapy together with lifestyle changes is used to treat obesity and T2DM to decrease the incidence of comorbidities and all-cause mortality and to increase life expectancy. Bariatric surgery is increasingly replacing other forms of treatment of morbid obesity, especially in patients with refractory obesity, owing to its many benefits including good long-term outcomes and almost no weight regain. The bariatric surgery options have markedly changed recently, and laparoscopic sleeve gastrectomy (LSG) is gradually gaining popularity. LSG has become an effective and safe treatment for type-2 diabetes and morbid obesity, with a high cost-benefit ratio. Here, we review the me-chanism associated with LSG treatment of T2DM, and we discuss clinical studies and animal experiments with regard to gastrointestinal hormones, gut microbiota, bile acids, and adipokines to clarify current treatment modalities for patients with obesity and T2DM.

Association of predicted fat mass and lean body mass with diabetes: a longitudinal cohort study in an Asian population

Objective

The relationship between body composition fat mass (FM) and lean body mass (LBM) and diabetes risk is currently debated, and the purpose of this study was to examine the association of predicted FM and LBM with diabetes in both sexes.

Methods

The current study was a secondary analysis of data from the NAGALA (NAfld in the Gifu Area, Longitudinal Analysis) cohort study of 15,463 baseline normoglycemic participants. Predicted LBM and FM were calculated for each participant using anthropometric prediction equations developed and validated for different sexes based on the National Health and Nutrition Examination Survey (NHANES) database, and the outcome of interest was diabetes (types not distinguished) onset. Multivariate Cox regression analyses were applied to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations of predicted FM and LBM with diabetes risk and further visualized their associations using a restricted cubic spline function.

Results

The incidence density of diabetes was 3.93/1000 person-years over a mean observation period of 6.13 years. In women, predicted LBM and FM were linearly associated with diabetes risk, with each kilogram increase in predicted LBM reducing the diabetes risk by 65% (HR 0.35, 95%CI 0.17, 0.71; P < 0.05), whereas each kilogram increase in predicted FM increased the diabetes risk by 84% (HR 1.84, 95%CI 1.26, 2.69; P < 0.05). In contrast, predicted LBM and FM were non-linearly associated with diabetes risk in men (all P for non-linearity < 0.05), with an L-shaped association between predicted LBM and diabetes risk and a saturation point that minimized the risk of diabetes was 45.4 kg, while predicted FM was associated with diabetes risk in a U-shape pattern and a threshold point with the lowest predicted FM-related diabetes risk was 13.76 kg.

Conclusion

In this Asian population cohort, we found that high LBM and low FM were associated with lower diabetes risk according to anthropometric equations. Based on the results of the non-linear analysis, we believed that it may be appropriate for Asian men to keep their LBM above 45.4 kg and their FM around 13.76 kg.