The ominous triad of adipose tissue dysfunction: inflammation, fibrosis, and impaired angiogenesis

Microbial succinate promotes the response to metformin by upregulating secretory immunoglobulin a in intestinal immunity

Metformin is the first-line pharmacotherapy for type 2 diabetes mellitus; however, many patients respond poorly to this drug in clinical practice. The potential involvement of microbiota-mediated intestinal immunity and related signals in metformin responsiveness has not been previously investigated. In this study, we successfully constructed a humanized mouse model by fecal transplantation of the gut microbiota from clinical metformin-treated - responders and non-responders, and reproduced the difference in clinical phenotypes of responsiveness to metformin. The abundance of Bacteroides thetaiotaomicron, considered a representative differential bacterium of metformin responsiveness, and the level of secretory immunoglobulin A (SIgA) in intestinal immunity increased significantly in responder recipient mice following metformin treatment. In contrast, no significant alterations in B. thetaiotaomicron and SIgA were observed in non-responder recipient mice. The study of IgA-/- mice confirmed that downregulated expression or deficiency of SIgA resulted in non-response to metformin, meaning that metformin was unable to improve dysfunctional glucose metabolism and reduce intestinal and adipose tissue inflammation, ultimately leading to systemic insulin resistance. Furthermore, supplementation with succinate, a microbial product of B. thetaiotaomicron, potentially reversed the non-response to metformin by inducing the production of SIgA. In conclusion, we demonstrated that upregulated SIgA, which could be regulated by succinate, was functionally involved in metformin response through its influence on immune cell-mediated inflammation and insulin resistance. Conversely, an inability to regulate SIgA may result in a lack of response to metformin.

Salvia hispanica L. (chia) seed have beneficial effects upon visceral adipose tissues extracellular matrix disorders and inflammation developed in a sucrose-rich diet-induced adiposity rodent model

We have previously demonstrated that dietary Salvia hispanica L. (chia) seed, rich in α-linolenic acid (ALA), was able to reduce visceral adiposity and improves insulin sensitivity in a rodent experimental model of adiposity induced by the administration of a sucrose-rich diet (SRD). The evidence suggests that the pathological expansion of visceral adipose tissue (VAT) is accompanied by changes in the extracellular matrix (ECM) components, which can lead to fibrosis, and/or a greater expression of pro-inflammatory adipokines. The aim of the present work was to evaluate the effect of chia seed administration upon key components and modulators of ECM remodeling and inflammation in different white adipose tissues (WAT) (epididymal-eWAT- and retroperitoneal-rWAT-) in a SRD-induced adiposity rodent model. The results showed that chia seed reduced the increased hydroxyproline levels observed in SRD-fed group and this was accompanied by changes in the activity/expression of matrix metalloproteinases MMP-2 and MMP-9. No changes were observed in transforming growth factor β (TGF-β) expression levels. In addition, this nutritional intervention was able to reduce the levels of PAI-1 and MCP-1, and to increase the levels of adiponectin in both VAT. An increase in the ratio of n-3/n-6 polyunsaturated fatty acids in the membrane phospholipids of both VAT was also observed. The present study demonstrated that chia seed have anti-fibrotic and anti-inflammatory actions in the VAT which could play a key role in the amelioration of visceral adiposity and whole-body insulin insensitivity developed in SRD-fed rats.

Overnutrition causes insulin resistance and metabolic disorder through increased sympathetic nervous system activity

The mechanisms underlying obesity-induced insulin resistance remain incompletely understood, as impaired cellular insulin signaling, traditionally considered the primary driver of insulin resistance, does not always accompany impaired insulin action. Overnutrition rapidly increases plasma norepinephrine (NE), suggesting overactivation of the sympathetic nervous system (SNS). However, the role of the SNS in obesity is controversial, as both increased and decreased SNS activity (SNA) have been reported. Here, we show that reducing catecholamine (CA) release from the SNS protects against overnutrition-induced insulin resistance as well as hyperglucagonemia, adipose tissue dysfunction, and fatty liver disease, as we demonstrate utilizing a mouse model of inducible and peripherally restricted deletion of tyrosine hydroxylase (th; THΔper). A key mechanism through which heightened SNA induces insulin resistance is by triggering adipose tissue lipolysis. Increased SNA emerges as a critical driver in the pathogenesis of overnutrition-induced insulin resistance and metabolic disease independent of cellular insulin signaling.

Impaired suppression of fatty acid release by insulin is a strong predictor of reduced whole-body insulin-mediated glucose uptake and skeletal muscle insulin receptor activation

AIM

To examine factors underlying why most, but not all, adults with obesity exhibit impaired insulin-mediated glucose uptake, we compared: (1) adipose tissue fatty acid (FA) release, (2) skeletal muscle lipid droplet (LD) characteristics, and (3) insulin signalling events, in skeletal muscle of adults with obesity with relatively high versus low insulin-mediated glucose uptake.

METHODS

Seventeen adults with obesity (BMI: 36 ± 3 kg/m2) completed a 2 h hyperinsulinemic-euglycemic clamp with stable isotope tracer infusions to measure glucose rate of disappearance (glucose Rd) and FA rate of appearance (FA Ra). Skeletal muscle biopsies were collected at baseline and 30 min into the insulin infusion. Participants were stratified into HIGH (n = 7) and LOW (n = 10) insulin sensitivity cohorts by their glucose Rd during the hyperinsulinemic clamp (LOW< 400; HIGH >550 nmol/kgFFM/min/[μU/mL]).

RESULTS

Insulin-mediated suppression of FA Ra was lower in LOW compared with HIGH (p < 0.01). In skeletal muscle, total intramyocellular lipid content did not differ between cohorts. However, the size of LDs in the subsarcolemmal region (SS) of type II muscle fibres was larger in LOW compared with HIGH (p = 0.01). Additionally, insulin receptor-β (IRβ) interactions with regulatory proteins CD36 and Fyn were lower in LOW versus HIGH (p < 0.01), which aligned with attenuated insulin-mediated Tyr phosphorylation of IRβ and downstream insulin-signalling proteins in LOW.

CONCLUSION

Collectively, reduced ability for insulin to suppress FA mobilization, with accompanying modifications in intramyocellular LD size and distribution, and diminished IRβ interaction with key regulatory proteins may be key contributors to impaired insulin-mediated glucose uptake commonly found in adults with obesity.

Exploring the Complexity of Pan-Cancer: Gene Convergences and in silico Analyses

Cancer is a complex and multifaceted group of diseases characterized by highly intricate mechanisms of tumorigenesis and tumor progression, which complicates diagnosis, prognosis, and treatment. In recent years, targeted therapies have gained prominence by focusing on specific mutations and molecular features unique to each tumor type, offering more effective and personalized treatment options. However, it is equally critical to explore the genetic commonalities across different types of cancer, which has led to the rise of pan-cancer studies. These approaches help identify shared therapeutic targets across various tumor types, enabling the development of broader and potentially more widely applicable treatment strategies. This review aims to provide a comprehensive overview of key concepts related to tumors, including tumorigenesis processes, the tumor microenvironment, and the role of extracellular vesicles in tumor biology. Additionally, we explore the molecular interactions and mechanisms driving tumor progression, with a particular focus on the pan-cancer perspective. To achieve this, we conducted an in silico analysis using publicly available datasets, which facilitated the identification of both common and divergent genetic and molecular patterns across different tumor types. By integrating these diverse areas, this review offers a clearer and deeper understanding of the factors influencing tumorigenesis and highlights potential therapeutic targets.

Targeting GSK-3β for adipose dysfunction and cardiovascular complications of metabolic disease: An entangled WNT/β-catenin question

Individuals with metabolic syndrome have a high risk of developing cardiovascular disorders that is closely tied to visceral adipose tissue dysfunction, as well as an altered interaction between adipose tissue and the cardiovascular system. In metabolic syndrome, adipose tissue dysfunction is associated with increased hypertrophy, reduced vascularization, and hypoxia of adipocytes, leading to a pro-oxidative and pro-inflammatory environment. Among the pathways regulating adipose tissue homeostasis is the wingless-type mammary tumor virus integration site family (Wnt) signaling pathway, with both its canonical and non-canonical arms. Various modulators of the Wnt signaling have been identified to contribute to the development of metabolic diseases and their cardiovascular complications, with a particularly significant role played by Glycogen Synthase Kinase-3β (GSK-3β). GSK-3β levels and activities have various and often contrasting roles in obesity and related metabolic disorders, as well as their cardiovascular sequelae. Here, we explore the possibility that altered Wnt signaling and GSK-3β activities could serve as a connection between adipose tissue dysfunction and the development of cardiovascular disease in individuals with metabolic syndrome. We attempt to define a context-specific approach for intervention, which could possibly serve as a novel disease modifying therapy for the mitigation of such complications.

Follistatin like-1 (Fstl1) regulates adipose tissue development in zebrafish

Obesity is a highly prevalent disorder with complex aetiology. Therefore, studying its associated cellular and molecular pathways may be aided by analysing genetic tractable diseases. In this context, the study of ciliopathies such as Bardet-Biedl syndrome has highlighted the relevance of primary cilia in obesity, both in the central nervous system and peripheral tissues. Based on our previous in vitro results supporting the role of a novel Bbs4-cilia-Fstl1 axis in adipocyte differentiation, we evaluated the in vivo relevance of the zebrafish orthologous genes fstl1a and fstl1b in primary cilia and adipose tissue development. Using a combination of knockdowns and a new fstl1a mutant line, we show that fstl1a promotes primary cilia formation in early embryos and participates in adipose tissue formation in larvae. We also show that fstl1b partially compensates for the loss of fstl1a. Moreover, in high fat diet, fstl1a depletion affects the expression of differentiation and mature adipocyte markers. These results agree with our previous in vitro data and provide further support for the role of FSTL1 as a regulator of adipose tissue formation. Dissecting the exact biological role of proteins such as FSTL1 will likely contribute to understand obesity onset and presentation.

The multifactorial effect of obesity on the effectiveness and outcomes of cancer therapies

Epidemiology studies have demonstrated a clear association between obesity and the development of several distinct malignancies, with excessive visceral adiposity being an increasingly prevalent feature in patients with cancer presenting for therapeutic intervention. Clinical trials and meta-analyses have helped to inform effective and safe dosing of traditional systemically administered anticancer agents in adult patients with cancer and obesity, but there remains much debate not only regarding the effect of obesity on the more novel targeted molecular and immune-based therapies, but also about how obesity is best defined and measured clinically. Low muscle mass is associated with poor outcomes in cancer, and body composition studies using biochemical and imaging modalities are helping to fully delineate the importance of both obesity and sarcopenia in clinical outcomes; such studies might also go some way to explaining how obesity can paradoxically be associated with favourable clinical outcomes in certain cancers. As the cancer survivorship period increases and the duration of anticancer treatment lengthens, this Review highlights the challenges facing appropriate treatment selection and emphasizes how a multidisciplinary approach is warranted to manage weight and skeletal muscle loss during and after cancer treatment.

Predictors for Irreversibility of Contrast-Induced Acute Kidney Injury in Patients with Obesity After Contrast-Enhanced Computed Tomography Coronary Angiography

INTRODUCTION

Although contrast-induced (CI) acute kidney injury (AKI) is a common complication in high-risk individuals requiring evaluation with contrast-enhanced angiography, the possible predictors of CI-AKI in patients with obesity are not fully understood. The aim of this study was to elucidate plausible factors associated with the irreversibility of CI-AKI in individuals with obesity undergoing contrast-enhanced computed tomography coronary angiography.

METHODS

A total of 96 adult patients with obesity and the KDIGO criteria of CI-AKI (increase of serum levels of creatinine ≥ 25% or ≥ 500 µmol/L at 48 h after procedure) were retrospectively screened from the cohort of 1833 patients who underwent iodine contrast medium (ICM)-enhanced computed tomography coronary angiography, and were included in the study. The patients were divided into two cohorts: 96 adult patients with obesity and recovery of CI-AKI in 7 days after initiating of the event, and 57 individuals with irreversibility of CI-AKI. Serum concentrations of conventional biochemistry and urine biomarkers [i.e., hemoglobin, creatinine, high-sensitivity C-reactive protein, urinary albumin/creatinine ratio (UACR)] as well as natriuretic peptide, adropin, apelin, irisin, tumor necrosis factor-alpha (TNF-alpha), were determined at baseline. The levels of creatinine were measured at baseline, at the event, and in 7 days after the event.

RESULTS

We identified 12 variables, which were associated with irreversibility of CI-AKI: age > 75 years [odds ratio (OR) = 1.22. P = 0.001], male gender (OR = 1.03, P = 0.042), stable coronary artery disease (OR = 1.06, P = 0.048), chronic kidney disease (CKD) 1-3 grade (OR = 1.60, P = 0.001), heart failure with preserved ejection fraction (HFpEF) (OR = 1.07, P = 0.046), baseline estimated GFR < 80 mL/min/1.73 m2 (OR = 1.10, P = 0.040), UACR > 17.5 mg/g Cr (OR = 1.05, P = 0.048), TNF-alpha > 3.11 pg/mL (OR = 1.12, P = 0.001), and adropin < 2.43 ng/mL (OR = 1.18, P = 0.001). After adjustment for CKD and UACR > 17.5 mg/g Cr, only HFpEF (OR = 1.06, P = 0.042) and adropin < 2.43 ng/mL (OR = 1.11, P = 0.001) remained independent predictors of CI-AKI irreversibility. Yet, adropin < 2.43 ng/mL at baseline exerted sufficiently better predictive ability than both HFpEF and preexisting CKD 1-3 grade.

CONCLUSION

In a multivariate prediction model adjusted for CKD and urinary albumin/creatinine ratio > 17.5 mg/g Cr, low levels of adropin (< 2.43 ng/mL) in individuals with non-morbid obesity together with the presence of HFpEF were independent predictors of CI-AKI irreversibility after ICM-enhanced computed tomography coronary angiography.

Efficacy and safety of diacerein monotherapy in adults with obesity: A randomized, double-blind, placebo-controlled trial

AIM

To assess the efficacy and safety of diacerein monotherapy in adults with obesity.

METHODS

Forty-two adults with obesity participated in the study and were randomly assigned to receive diacerein or placebo in addition to lifestyle modification for 14 weeks, in a double-blinded fashion. Differences in changes in body weight, body composition, metabolic variables, fatty liver-related indicators, cardiovascular system variables, lifestyle score and metabolic factors were compared.

RESULTS

Post-treatment weight loss percentage from baseline was -6.56% (-8.71%, -4.41%) in the diacerein group and -0.59% (-2.74%, 1.56%) in the placebo group. Compared with the placebo group, the diacerein group showed significant improvements in body composition, metabolic variables and indicators related to fatty liver. In addition, after 14 weeks of treatment, diacerein led to a significant reduction in serum visfatin concentration versus the placebo group. The reductions in total body fat mass and visceral fat area mediated the weight loss induced by diacerein. No significant differences were found between the groups in the number of adverse events and safety variables.

CONCLUSIONS

For adults with obesity, diacerein led to a clinically meaningful weight loss and provided multiple metabolic benefits with acceptable safety. These results support that diacerein is a promising candidate medicine to be developed for obesity management.

Epicardial fat density obtained with computed tomography imaging - more important than volume?

Epicardial adipose tissue (EAT) is a unique fat depot located between the myocardium and the visceral layer of pericardium. It can be further subdivided into pericoronary (PCAT), periatrial (PAAT) and periventricular adipose tissue (PVentAT), each of them exhibiting specific characteristics and association with the underlying tissue. Since no physical barrier separates EAT from the myocardium, this fat tissue can easily interact with the underlying cardiac structure. EAT can be visualized using various imaging modalities. Computed tomography provides not only information on EAT volume, but also on its density. Indeed, EAT density reflected by the recently developed fat attenuation index (FAI) is emerging as a useful index of PCAT inflammation, PAAT inflammation and fibrosis, while the relevance of density of PVentAT is much less known. The emerging data indicates that FAI can be an important diagnostic and prognostic tool in both coronary artery disease and atrial fibrillation. Future studies will demonstrate if it also could be used as a marker of efficacy of therapies and whether FAI PVentAT could indicate ventricular pathologies, such as heart failure. The aim of the review is to present computed tomography derived FAI as an important tool both to study and better understand the epicardial fat and as a potential predictive marker in cardiovascular disorders.

Weight Changes Are Linked to Adipose Tissue Genes in Overweight Women with Polycystic Ovary Syndrome

Women with polycystic ovary syndrome (PCOS) have varying difficulties in achieving weight loss by lifestyle intervention, which may depend on adipose tissue metabolism. The objective was to study baseline subcutaneous adipose tissue gene expression as a prediction of weight loss by lifestyle intervention in obese/overweight women with PCOS. This is a secondary analysis of a randomized controlled trial where women with PCOS, aged 18-40 and body mass index (BMI) ≥ 27 were initially randomized to either a 4-month behavioral modification program or minimal intervention according to standard care. Baseline subcutaneous adipose tissue gene expression was related to weight change after the lifestyle intervention. A total of 55 obese/overweight women provided subcutaneous adipose samples at study entry. Weight loss was significant after behavioral modification (-2.2%, p = 0.0014), while there was no significant weight loss in the control group (-1.1%, p = 0.12). In microarray analysis of adipose samples, expression of 40 genes differed significantly between subgroups of those with the greatest weight loss or weight gain. 10 genes were involved in metabolic pathways including glutathione metabolism, gluconeogenesis, and pyruvate metabolism. Results were confirmed by real-time polymerase chain reaction (RT-PCR) in all 55 subjects. Expressions of GSTM5, ANLN, and H3C2 correlated with weight change (R = -0.41, p = 0.002; R = -0.31, p = 0.023 and R = -0.32, p = 0.016, respectively). GSTM5, involved in glutathione metabolism, was the strongest predictor of weight loss, and together with baseline waist-hip ratio (WHR) explained 31% of the variation in body weight change. This study shows that baseline subcutaneous adipose tissue genes play a role for body weight outcome in response to lifestyle intervention in overweight/obese women with PCOS.

Chronic Peroxisome Proliferator-Activated Receptor α/γ and Cannabinoid Receptor 2 Agonist Treatments Attenuated Visceral Adipose Tissue (VAT)-Derived Extracellular Vesicle-Related VAT and Intestinal Abnormalities in Nonalcoholic Steatohepatitis Mice

This study explores the mechanisms and combined effects of chronic peroxisome proliferator-activated receptor (PPAR)α/γ and cannabinoid receptor 2 (CB2R) agonists on visceral adipose tissue (VAT)-derived extracellular vesicle (EV) release and associated systemic/VAT inflammation, decreased VAT capillary density/fibrosis, and intestinal inflammation/hyperpermeability in nonalcoholic steatohepatitis (NASH) mice. NASH mice received 1 month of PPARα/γ agonist aleglitazar (10 mg/kg per day) or CB2R agonist JWH015 (3 mg/kg per day) alone or combined. High EV release from VAT of NASH mice was associated with severe systemic/VAT/intestinal inflammation, reduced capillary network of VAT, and intestinal hyperpermeability. Combined JWH015 with aleglitazar treatment significantly suppressed high-fat diet-induced obesity/adiposity, inhibited VAT expansion, reduced VAT inflammation/fibrosis, normalized VAT capillary network, and attenuated intestinal mucosal injury, inflammation, and hyperpermeability in NASH + aleglitazar + JWH015 mice. The inhibition of AT-derived EV release and hypoxia-inducible factor (HIF)1α levels in AT-derived EV, normalization of CB2R, PPARα, PPARγ, PPARγ1, PPARγ2, tight junction proteins, vascular endothelial growth factor/CD31 expression, and down-regulation of HIF1α, monocyte chemoattractant protein-1, and transforming growth factor-β1 were observed in the VAT and intestine of the NASH + aleglitazar + jwh015 group. In vitro experiments revealed that PPARα/γ and CB2R activation attenuated NASH AT-derived EV-induced pathogenic changes in the J774/SVEC4-10/Caco2/3T3-L1 cell system. This study suggested that VAT-derived EVs contribute to the pathogenesis of nonalcoholic fatty liver disease and that combined PPARα/γ and CB2R agonist treatment reduces VAT-released EV release and HIF1/monocyte chemoattractant protein-1 signals to ameliorate hepatic steatosis and VAT/intestine abnormalities of NASH mice.

Time-Restricted Feeding Attenuates Adipose Tissue Inflammation and Fibrosis in Mice Under Chronic Light Exposure

Time-restricted feeding (TRF) has emerged as a promising dietary approach for improving metabolic parameters associated with obesity. However, it remains largely unclear whether TRF offers benefits for obesity related to exposure to light at night. This study examined whether lean and obese mice under chronic light exposure could benefit from TRF intervention. Six-week-old C57BL/6 male mice were fed either a low-fat diet or a high-fat diet under a 12 h light/12 h dark cycle for 6 weeks. They were then divided into three subgroups: control light, chronic 24 h light, and chronic light with a daily 10 h TRF. Chronic light exposure led to increased weight gain and higher expression of inflammatory and fibrotic markers in the adipose tissue of both lean and obese mice. It also increased hepatic triglyceride content in mice, regardless of their weight status. TRF protected both lean and obese mice from weight gain, normalized inflammatory and fibrotic gene expression, and reduced adipose tissue collagen and liver triglyceride accumulation caused by light exposure alone or in combination with obesity. These results suggest that TRF could have clinical implications for preventing obesity associated with night shift work, regardless of current weight status.

Specific calcium deposition on pre-procedural CCTA at the time of percutaneous coronary intervention predicts in-stent restenosis in symptomatic patients

PURPOSE

To characterize preprocedural coronary atherosclerotic lesions derived from CCTA and assess their association with in-stent restenosis (ISR) after percutaneous coronary intervention (PCI).

MATERIALS AND METHODS

This retrospective cohort-study included patients who underwent CCTA for suspected coronary artery disease, subsequent index angiography including PCI and surveillance angiography within 6-8 months after the index procedure. We performed a plaque analysis of culprit lesions on CCTA using a dedicated plaque analysis software including assessment of the surrounding pericoronary fat attenuation index (FAI) and compared findings between lesions with and without ISR at surveillance angiography after stenting.

RESULTS

Overall 278 coronary lesions in 209 patients were included. Of these lesions, 43 (15.5 ​%) had ISR at surveillance angiography after stenting while 235 (84.5 ​%) did not. Likewise, plaque composition such as volume of calcification [129.8 mm3 (83.3-212.6) vs. 94.4 mm3 (60.4-160.5) p ​= ​0.06] and lipid-rich and fibrous plaque volume [38.4 mm3 (19.4-71.2) vs. 38.0 mm3 (14.0-59.1), p ​= ​0.11 and 50.4 mm3 (26.1-77.6) vs. 42.1 mm3 (31.1-60.3), p ​= ​0.16] between lesion with and without ISR were not statistically significant. However lesions associated with ISR were more eccentric (n ​= ​37, 86.0 ​% versus n ​= ​159, 67,7 ​%; p ​= ​0.03) and more frequently demonstrated calcified portions on opposite sides on the vessel wall on cross-sectional datasets (n ​= ​24, 55.8 ​% versus n ​= ​55, 23.4 ​%, p ​= ​0.001). FAIlesion was significantly different in lesions with ISR as compared to those without ISR [-76.5 (-80.1 to -73.6) vs. -80.9 (-88.9 to -74.0), p ​= ​0.02]. There was no difference with respect to FAIRCA between the two groups [-77.4 (-81.9 to -75.6) vs. -78.5 (-86.0 to -71.0), p ​= ​0.41].

CONCLUSION

Coronary lesions associated with ISR at surveillance angiography demonstrated differences in the arrangement of calcified portions as well as an increased lesion-specific pericoronary fat attenuation index at baseline CCTA. This latter finding suggests that perivascular inflammation at baseline may play a major role in the development of in-stent restenosis.

Association between Serum Fatty Acids Profile and MetScore in Women with Severe Obesity

BACKGROUND

Metabolic syndrome (MetS) is a set of conditions associated with an increased cardiovascular risk. Several serum fatty acids (FAs) seem to play an essential role in the development of cardiometabolic diseases and mortality. Thus, it is imperative to explore the impact of FAs on MetS parameters, using an early MetS screening tool such as MetScore, which is readily available in clinical practice.

AIM

The aim of this study was to assess the potential correlation between serum FAs and cardiovascular risk using a MetScore.

METHODS

This cross-sectional study involved 41 women with severe obesity. The MetScore was calculated, and participants were categorized into high- and low-cardiovascular-risk groups based on the median MetScore value. Gas chromatography was used to quantify serum FAs. Generalized Linear Models were used to compare group means. The association was assessed through simple logistic regression, and an adjusted logistic regression was conducted to validate the association between Metscore and serum FAs.

RESULTS

The high-cardiovascular-risk group exhibited elevated values of HOMA-IR, palmitic, oleic, cis-vaccenic, and monounsaturated fatty acids, as well as the SCD-18C, indicating a heightened cardiovascular risk. Conversely, HDL-c, QUICK, gamma-linolenic, and eicosatetraenoic fatty acids showed lower values compared to the low-risk group.

CONCLUSIONS

Women with severe obesity and high cardiovascular risk have lower values of some omega-3 and omega-6 FAs, considered cardioprotective and anti-inflammatory, and have higher lipogenic activity and FAs, correlated with high cardiovascular risk. These findings emphasize the need to address lipid metabolism in this population as a therapeutic target to reduce cardiovascular risk. Future research should explore clinical interventions that modulate fatty acid metabolism to mitigate cardiometabolic complications.

Adipocyte lipin 1 expression associates with human metabolic health and regulates systemic metabolism in mice

Dysfunctional adipose tissue is believed to promote the development of hepatic steatosis and systemic insulin resistance, but many of the mechanisms involved are still unclear. Lipin 1 catalyzes the conversion of phosphatidic acid to diacylglycerol (DAG), the penultimate step of triglyceride synthesis, which is essential for lipid storage. Herein we found that adipose tissue LPIN1 expression is decreased in people with obesity compared to lean subjects, and low LPIN1 expression correlated with multi-tissue insulin resistance and increased rates of hepatic de novo lipogenesis. Comprehensive metabolic and multi-omic phenotyping demonstrated that adipocyte-specific Lpin1-/- mice had a metabolically-unhealthy phenotype, including liver and skeletal muscle insulin resistance, hepatic steatosis, increased hepatic de novo lipogenesis, and transcriptomic signatures of metabolically associated steatohepatitis that was exacerbated by high-fat diets. We conclude that adipocyte lipin 1-mediated lipid storage is vital for preserving adipose tissue and systemic metabolic health, and its loss predisposes mice to metabolically associated steatohepatitis.

Sex Differences in Fat Distribution and Muscle Fat Infiltration in the Lower Extremity: A Retrospective Diverse-Ethnicity 7T MRI Study in a Research Institute Setting in the USA

Background: Fat infiltration in skeletal muscle is related to declining muscle strength, whereas excess subcutaneous fat is implicated in the development of metabolic diseases. Methods: Using multi-slice axial T2-weighted (T2w) MR images, this retrospective study characterized muscle fat infiltration (MFI) and fat distribution in the lower extremity of 107 subjects (64M/43F, age 11-79 years) with diverse ethnicities (including White, Black, Latino, and Asian subjects). Results: MRI data analysis shows that MFI, evaluated by the relative intensities of the pixel histogram profile in the calf muscle, tends to increase with both age and BMI. However, statistical significance was found only for the age correlation in women (p < 0.002), and the BMI correlation in men (p = 0.04). Sex disparities were also seen in the fat distribution, which was assessed according to subcutaneous fat thickness (SFT) and the fibula bone marrow cross-sectional area (BMA). SFT tends to decrease with age in men (p < 0.01), whereas SFT tends to increase with BMI only in women (p < 0.01). In contrast, BMA tends to increase with age in women (p < 0.01) and with BMI in men (p = 0.04). Additionally, MFI is positively correlated with BMA but not with SFT, suggesting that compromised bone structure may contribute to fat infiltration in the surrounding skeletal muscle. Conclusions: The findings of this study highlight a sex factor affecting MFI and fat distribution, which may offer valuable insights into effective strategies to prevent and treat MFI in women versus men.

Aging reveals a sex-dependent susceptibility of sarcospan-deficient mice to cardiometabolic disease

Numerous genes including sarcospan (SSPN) have been designated as obesity-susceptibility genes by human genome-wide association studies. Variants in the SSPN locus have been linked with sex-dependent obesity-associated traits; however, this association has not been investigated in vivo. To delineate the role SSPN plays in regulating metabolism with potential to impact cardiac function, we subjected young and aged global SSPN-deficient (SSPN-/-) male and female mice to obesogenic conditions (60% fat diet). We hypothesized that loss of SSPN combined with metabolic stress would increase susceptibility of mice to cardiometabolic disease. Baseline and end-point assessments of several anthropometric parameters were performed including weight, glucose tolerance, and fat distribution of mice fed control (CD) and high-fat (HFD) diet. Doppler echocardiography was used to monitor cardiac function. White adipose and cardiac tissues were assessed for inflammation by histological, gene expression, and cytokine analysis. Overall, SSPN deficiency protected both sexes and ages from diet-induced obesity, with a greater effect in females. SSPN-/- HFD mice gained less weight than wild-type (WT) cohorts, while SSPN-/- CD groups increased weight. Furthermore, aged SSPN-/- mice developed glucose intolerance regardless of diet. Echocardiography showed preserved systolic function for all groups; however, aged SSPN-/- males exhibited significant increases in left ventricular mass (CD) and signs of diastolic dysfunction (HFD). Cytokine analysis revealed significantly increased IL-1α and IL-17Α in white adipose tissue from young SSPN-/- male mice, which may be protective from diet-induced obesity. Overall, these studies suggest that several sex-dependent mechanisms influence the role SSPN plays in metabolic responses that become evident with age.NEW & NOTEWORTHY Young and aged sarcospan (SSPN)-deficient mice were examined to assess the role of SSPN in obesity and cardiometabolic disease. Both sexes displayed a "leaner" phenotype in response to high-fat diet (HFD). Notably, several sex differences were identified in aged SSPN-deficient mice: 1) females developed glucose intolerance (control and HFD) and 2) males exhibited increased left ventricular mass (control) and diastolic dysfunction (HFD). Therefore, we conclude that SSPN exerts a sex-dependent influence on obesity-associated diseases.

Adipose Tissue Plasticity: A Comprehensive Definition and Multidimensional Insight

Adipose tissue is composed of adipocytes, stromal vascular fraction, nerves, surrounding immune cells, and the extracellular matrix. Under various physiological or pathological conditions, adipose tissue shifts cellular composition, lipid storage, and organelle dynamics to respond to the stress; this remodeling is called "adipose tissue plasticity". Adipose tissue plasticity includes changes in the size, species, number, lipid storage capacity, and differentiation function of adipocytes, as well as alterations in the distribution and cellular composition of adipose tissue. This plasticity has a major role in growth, obesity, organismal protection, and internal environmental homeostasis. Moreover, certain thresholds exist for this plasticity with significant individualized differences. Here, we comprehensively elaborate on the specific connotation of adipose tissue plasticity and the relationship between this plasticity and the development of many diseases. Meanwhile, we summarize possible strategies for treating obesity in response to adipose tissue plasticity, intending to provide new insights into the dynamic changes in adipose tissue and contribute new ideas to relevant clinical problems.

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.

Targeting the Epigenetic Marks in Type 2 Diabetes Mellitus: Will Epigenetic Therapy Be a Valuable Adjunct to Pharmacotherapy?

Although genetic, environmental, and lifestyle factors largely contribute to type 2 diabetes mellitus (T2DM) risk, the role of epigenetics in its pathogenesis is now well established. The epigenetic mechanisms in T2DM mainly consist of DNA methylation, histone modifications and regulation by noncoding RNAs (ncRNAs). For instance, DNA methylation at CpG islands in the promoter regions of specific genes encoding insulin signaling and glucose metabolism suppresses these genes. Modulating the enzyme mediators of these epigenetic marks aims to restore standard gene expression patterns and improve glycemic control. In targeting these epigenetic marks, using epigenetic drugs such as DNA methyltransferase (DNAMT), histone deacetylase (HDAC) and histone acetyltransferase (HAT) inhibitors has led to variable success in humans and experimental murine models. Specifically, the United States' Food and Drug Administration (US FDA) has approved DNAMT inhibitors like 5-azacytidine and 5-aza-2'-deoxycytidine for use in diabetic retinopathy: a T2DM microvascular complication. These DNAMT inhibitors block the genes for methylation of mitochondrial superoxide dismutase 2 (SOD2) and matrix metallopeptidase 9 (MMP-9): the epigenetic marks in diabetic retinopathy. Traditional pharmacotherapy with metformin also have epigenetic effects in T2DM and positively alter disease outcomes when combined with epigenetic drugs like DNAMT and HDAC inhibitors, raising the prospect of using epigenetic therapy as a valuable adjunct to pharmacotherapy. However, introducing small interfering RNAs (siRNAs) in cells to silence specific target genes remains in the exploratory phase. Future research should focus on regulating gene expression in T2DM using long noncoding RNA (lncRNA) molecules, another type of ncRNA. This review discusses the epigenetics of T2DM and that of its macro- and microvascular complications, and the potential benefits of combining epigenetic therapy with pharmacotherapy for optimal results.

Label-free quantitative proteomic profiling reveals differential plasma protein expression in patients with obesity after treatment with liraglutide

Introduction

Treatment and management of obesity is clinically challenging. The inclusion of GLP-1 receptor agonists (GLP1RA) in the medical management of obesity has proven to be efficacious. However, mechanisms underlying the molecular changes arising from GLP1RA treatment in patients with obesity remain to be elucidated.

Methods

A single-center, prospective study was undertaken to evaluate the changes in the plasma proteins after liraglutide 3 mg therapy in twenty patients (M/F: 7/13) with obesity (mean BMI 40.65 ± 3.7 kg/m2). Anthropometric and laboratory parameters were measured, and blood samples were collected at two time points: baseline, before initiating treatment (pretreatment group, PT), and after three months of receiving the full dose liraglutide 3 mg (posttreatment group, PoT). An untargeted label-free LC MSMS mass spectrometric approach combined with bioinformatics and network pathway analysis was used to determine changes in the proteomic profiles.

Results

The mean age of the study participants was 36.0 ± 11.1 years. A statistically significant change was observed in weight, BMI and HbA1c levels between the PT and PoT groups (paired t-test, P < 0.001). A significant dysregulation was noted in the abundances of 151 proteins (31 up and 120 downregulated) between the two groups. The potential biomarkers were evaluated using receiver operating characteristic (ROC) curves. The top ten proteins (area under the curve (AUC) of 0.999 (95% CI)) were identified as potential biomarkers between PT and PoT groups and included Cystatin-B, major vault protein, and plastin-3, which were upregulated, whereas multimerin-2, large ribosomal P2, and proline-rich acidic protein 1 were downregulated in the PoT group compared with the PT group. The top network pathway identified using ingenuity pathway analysis (IPA), centered around dysregulation of MAPK, AKT, and PKc signaling pathways and related to cell-to-cell signaling and interaction, cellular assembly and organization, cellular compromise and a score of 46 with 25 focus proteins.

Discussion

Through label-free quantitative proteomic analysis, our study revealed significant dysregulation of plasma proteins after liraglutide 3 mg treatment in patients with obesity. The alterations in the proteomic profile between the PT and PoT groups demonstrated a decrease in levels of proteins involved in inflammation and oxidative stress pathways. On the other hand proteins involved in the glycolytic and lipolytic metabolic pathways as well as those participating in cytoskeletal and endothelial reorganization were observed to be increased. Understanding actions of liraglutide at a molecular and proteomic levels provides a holistic look into how liraglutide impacts metabolism, induces weight loss and improves overall metabolic health.

Matrix stiffness regulates the triad communication of adipocytes/macrophages/endothelial cells through CXCL13

Adipose tissue remodeling and plasticity are dynamically regulated by the coordinated functions of adipocytes, macrophages, and endothelial cells and extracellular matrix (ECM) that provides stiffness networks in adipose tissue component cells. Inflammation and fibrosis are crucial exogenous factors that dysregulate adipose tissue functions and drastically change the mechanical properties of the ECM. Therefore, communication among the ECM and adipose tissue component cells is necessary to understand the multifaceted functions of adipose tissues. To obtain in vivo stiffness, we used genipin as a crosslinker for collagen gels. Meanwhile, we isolated primary adipocytes, macrophages, and endothelial cells from C57BL/6J mice and incubated these cells in the differentiation media on temperature-responsive culture dishes. After the differentiation, these cell sheets were transferred onto genipin-crosslinked collagen gels with varying matrix stiffness. We found that inflammatory gene expressions were induced by hard matrix, whereas antiinflammatory gene expressions were promoted by soft matrix in all three types of cells. Interestingly, the coculture experiments of adipocytes, macrophages, and endothelial cells showed that the effects of soft or hard matrix stiffness stimulation on adipocytes were transmitted to the distant adipose tissue component cells, altering their gene expression profiles under normal matrix conditions. Finally, we identified that a hard matrix induces the secretion of CXCL13 from adipocytes, and CXCL13 is one of the important transmitters for stiffness communication with macrophages and endothelial cells. These findings provide insight into the mechanotransmission into distant cells and the application of stiffness control for chronic inflammation in adipose tissues with metabolic dysregulation.

Differentiating monogenic and syndromic obesities from polygenic obesity: Assessment, diagnosis, and management

Background

Obesity is a multifactorial neurohormonal disease that results from dysfunction within energy regulation pathways and is associated with increased morbidity, mortality, and reduced quality of life. The most common form is polygenic obesity, which results from interactions between multiple gene variants and environmental factors. Highly penetrant monogenic and syndromic obesities result from rare genetic variants with minimal environmental influence and can be differentiated from polygenic obesity depending on key symptoms, including hyperphagia; early-onset, severe obesity; and suboptimal responses to nontargeted therapies. Timely diagnosis of monogenic or syndromic obesity is critical to inform management strategies and reduce disease burden. We outline the physiology of weight regulation, role of genetics in obesity, and differentiating characteristics between polygenic and rare genetic obesity to facilitate diagnosis and transition toward targeted therapies.

Methods

In this narrative review, we focused on case reports, case studies, and natural history studies of patients with monogenic and syndromic obesities and clinical trials examining the efficacy, safety, and quality of life impact of nontargeted and targeted therapies in these populations. We also provide comprehensive algorithms for diagnosis of patients with suspected rare genetic causes of obesity.

Results

Patients with monogenic and syndromic obesities commonly present with hyperphagia (ie, pathologic, insatiable hunger) and early-onset, severe obesity, and the presence of hallmark characteristics can inform genetic testing and diagnostic approach. Following diagnosis, specialized care teams can address complex symptoms, and hyperphagia is managed behaviorally. Various pharmacotherapies show promise in these patient populations, including setmelanotide and glucagon-like peptide-1 receptor agonists.

Conclusion

Understanding the pathophysiology and differentiating characteristics of monogenic and syndromic obesities can facilitate diagnosis and management and has led to development of targeted pharmacotherapies with demonstrated efficacy for reducing body weight and hunger in the affected populations.

The role of adipose tissue dysfunction in hepatic insulin resistance and T2D

The root cause of type 2 diabetes (T2D) is insulin resistance (IR), defined by the failure of cells to respond to circulating insulin to maintain lipid and glucose homeostasis. While the causes of whole-body insulin resistance are multifactorial, a major contributing factor is dysregulation of liver and adipose tissue function. Adipose dysfunction, particularly adipose tissue-IR (adipo-IR), plays a crucial role in the development of hepatic insulin resistance and the progression of metabolic dysfunction-associated steatotic liver disease (MASLD) in the context of T2D. In this review, we will focus on molecular mechanisms of hepatic insulin resistance and its association with adipose tissue function. A deeper understanding of the pathophysiological mechanisms of the transition from a healthy state to insulin resistance, impaired glucose tolerance, and T2D may enable us to prevent and intervene in the progression to T2D.

Exploring the Impact of Astaxanthin Supplementation in Conjunction with a 12-Week CrossFit Training Regimen on Selected Adipo-Myokines Levels in Obese Males

OBJECTIVE

Obesity is associated with an exacerbated metabolic condition that is mediated through impairing balance in the secretion of some adipo-myokines. Therefore, the objective of the present study was to explore the impact of astaxanthin supplementation in conjunction with a 12-week CrossFit training regimen on some selected adipo-myokines, insulin insensitivity, and serum lipid levels in obese males.

MATERIAL AND METHODS

This study is a randomized control trial design; 60 obese males were randomly divided into four groups of 15, including the control group (CG), supplement group (SG), training group (TG), and combined training and supplement group (TSG). The participants were subjected to 12 weeks of astaxanthin (AST) supplementation [20 mg/d capsule, once/d] or CrossFit training or a combination of both interventions. The training regimen comprised 36 sessions of CrossFit, each lasting 60 min, conducted three times per week. The metabolic indices, body composition, anthropometrical, cardio-respiratory, and also some plasma adipo-myokine factors, including decorin (DCN), activin A, myostatin (MST), transforming growth factor (TGF)-β1, and follistatin (FST), were examined 12 and 72 h before the initiation of the main interventional protocols, and then 72 h after the final session of the training protocol.

RESULTS

There was no significant difference in the baseline data between the groups (p > 0.05). There were significant interactions between group x time for DCN (η2 = 0.82), activin A (η2 = 0.50), FST (η2 = 0.92), MST (η2 = 0.75), and TGFB-1 (η2 = 0.67) (p < 0.001 for all the variables). Significantly changes showed for DCN in TSG compared to TG and SG and also TG compared to SG (p = 0.0001); for activin A in SG compared to TG (p = 0.01) and TSG (p = 0.002); for FST in SG compared to TG and TSG (p = 0.0001), also in TSG compared to TG (p = 0.0001); for MST in SG, TG, and TSG compared to CG (p = 0.0001) and also in TSG compared to SG (p = 0.0001) and TG (p = 0.001); for TGFB-1 in SG, TG, and TSG compared to CG (p = 0.0001) and also TSG compared to SG (p = 0.0001) and TG (p = 0.001).

CONCLUSIONS

The 12-week CrossFit training concurrent with AST supplementation reduced anthropometric and metabolic factors and also serum lipid levels while producing positive changes in body composition and cardiovascular factors. Increased FST and DCN and reduced activin A, MST, and TGF-β1 were other affirmative responses to both interventions.

Diagnosis of perimenopausal coronary heart disease patients using radiomics signature of pericoronary adipose tissue based on coronary computed tomography angiography

To assess whether the radiomics signature of pericoronary adipose tissue (PCAT) from coronary computed tomography angiography (CCTA) can distinguish between perimenopausal women with coronary heart disease (CHD) and those without coronary artery disease (CAD). This single-center retrospective case-control study comprised 140 perimenopausal women with CHD presenting with chest pain who underwent CCTA within 48 h of admission. They were matched with 140 control patients presenting with chest pain but without CAD, based on age, risk factors, radiation dose and CT tube voltage. For all participants, PCAT around the proximal right coronary artery was segmented, from which radiomics features and the fat attenuation index (FAI) were extracted and analyzed. Subsequently, corresponding models were developed and internally validated using Bootstrap methods. Model performance was assessed through measures of identification, calibration, and clinical utility. Using logistic regression analysis, an integrated model that combines clinical features, fat attenuation index and radiomics parameters demonstrated enhanced discrimination ability for perimenopausal CHD (area under the curve [AUC]: 0.80, 95% confidence interval [CI]:0.740-0.845). This model outperformed both the combination of clinical features and PCAT attenuation (AUC 0.67, 95% CI 0.602-0.727) and the use of clinical features alone (AUC 0.66, 95% CI 0.603-0.732). Calibration curves for the three predictive models indicated satisfactory fit (all p > 0.05). Moreover, decision curve analysis demonstrated that the integrated model offered greater clinical benefit compared to the other two models. The CCTA-based radiomics signature derived from the PCAT model outperforms the FAI model in differentiating perimenopausal CHD patients from non-CAD individuals. Integrating PCAT radiomics with the FAI could enhance the diagnostic accuracy for perimenopausal CHD.

The involvement of epidural fat in ossification of the ligamentum flavum: From the perspective of exosomal proteome

Ossification of the ligamentum flavum (OLF) is the primary etiology of thoracic spinal stenosis. The functional properties of epidural fat (EF), an adipose tissue located in close proximity to ligamentum flavum (LF), have been scarcely investigated. The metabolic state of adipocytes significantly influences their functionality, and exosomes play a pivotal role in intercellular communication. This study aimed to investigate the role of EF-derived exosomes in OLF and characterize their protein profile by proteomics analysis. Our findings demonstrate that exosomes obtained from EF adjacent to OLF possess the ability to enhance osteogenesis of fibroblasts in vitro. Furthermore, proteomics analysis revealed metabolic dysfunction in EF adipocytes and identified lactate dehydrogenase A (LDHA) as a potential mediator involved in the development of OLF. This study provides new insights into the pathogenic mechanism underlying OLF and offers a theoretical basis for preventing and treating ligament ossification.

Association between metabolic obesity phenotypes and the risk of developing prostate cancer: a propensity score matching study based on Xinjiang

Background

Obesity-induced metabolic dysfunction increases the risk of developing tumors, however, the relationship between metabolic obesity phenotypes and prostate cancer (PCa) remains unclear.

Methods

The term metabolic obesity phenotypes was introduced based on metabolic status and BMI categories. Participants were categorized into four groups: metabolically healthy nonobesity (MHNO), metabolically healthy obesity (MHO), metabolically unhealthy nonobesity (MUNO), and metabolically unhealthy obesity (MUO). Propensity score matching was conducted based on age, ethnicity, marriage, etc. Univariate and multivariate conditional logistic regression analyses were used to assess the relationship between metabolic obesity phenotypes, metabolic risk factors, and PCa. Sensitivity analysis was performed to verify the robustness of the results.

Results

After propensity score matching among 564 PCa patients and 1418 healthy individuals, 209 were selected for each of the case and control groups. There were no statistically significant differences in the basic characteristics between the two groups. Univariate and multivariate conditional logistic regression suggested that the risk of developing PCa in both MHO and MUO individuals was higher than in MHNO individuals. Specifically, the risk of developing PCa in MHO individuals was 2.166 times higher than in MHNO individuals (OR=2.166, 95%CI: 1.133-4.139), and the risk in MUO individuals was is 2.398 times higher than in MHNO individuals(OR=2.398, 95%CI:1.271-4.523). Individuals with hyperglycemia and elevated triglycerides also had a higher risk of developing PCa (hyperglycemia:OR=1.488, 95%CI: 1.001-2.210; elevated triglycerides: OR=2.292, 95%CI: 1.419-3.702). Those with more than or equal to three metabolic risk factors had an increased risk of PCa (OR=1.990, 95%CI: 1.166-3.396). Sensitivity analysis indicated an increased risk of PCa in MUO individuals compared to MHNO individuals.

Conclusion

In this retrospective study, individuals with MHO and MUO had a higher risk of developing PCa.

Fructose vs. glucose: modulating stem cell growth and function through sugar supplementation

In multicellular organisms, stem cells are impacted by microenvironmental resources such as nutrient availability and oxygen tension for their survival, growth, and differentiation. However, the accessibility of these resources in the pericellular environment greatly varies from organ to organ. This divergence in resource availability leads to variations in the potency and differentiation potential of stem cells. This study aimed to explore the distinct effects of glucose and fructose, as well as different oxygen tensions, on the growth dynamics, cytokine production, and differentiation of stem cells. We showed that replacing glucose with fructose subjected stem cells to stress, resulting in increased Hif1α expression and stability, which in turn led to a reduction in cell proliferation, and alterations in cytokine production. However, fructose failed to induce differentiation of human mesenchymal stem cells (hMSCs) as well as mouse fibroblasts into mature adipocytes compared to glucose, despite the upregulation of key markers of adipogenesis, including C/EBPβ, and PPARγ. Conversely, we showed that fructose induced undifferentiated mouse fibroblasts to release cytokines associated with senescence, including IL1α1, IL6, IL8, MCP1, and TNF1α, suggesting that these cells were undergoing lipolysis. Taken together, our results suggest that altering the culture conditions through changes in hexose levels and oxygen tension places considerable stress on stem cells. Additional research is required to further characterize the mechanisms governing stem cell response to their microenvironments.

The impacts of obesity in rheumatoid arthritis and insights into therapeutic purinergic modulation

Rheumatoid Arthritis (RA) is an autoimmune condition responsible for the impairment of synovia and joints, endangering the functionality of individuals and contributing to mortality. Currently, obesity is increasing worldwide, and recent studies have suggested an association between such condition and RA. In this sense, obese individuals present a lower capacity for achieving remission and present more intense symptoms of the disease, demonstrating a link between both disorders. Different studies aim to understand the possible connection between the conditions; however, few is known in this sense. Therefore, knowing that obesity can alter the activity of multiple body systems, this work's objective is to evaluate the main modifications caused by obesity, which can be linked to the pathophysiology of RA, highlighting as relevant topics obesity's negative impact triggering systemic inflammation, intestinal dysbiosis, endocrine disbalances. Furthermore, the relationship between oxidative stress and obesity also deserves to be highlighted, considering the influence of reactive oxygen species (ROS) accumulation in RA exacerbation. Additionally, many of those characteristics influenced by obesity, along with the classic peculiarities of RA pathophysiology, can also be associated with purinergic signaling. Hence, this work suggests possible connections between the purinergic system and RA, proposing potential therapeutic targets against RA to be studied.

A Preliminary Study on Factors That Drive Patient Variability in Human Subcutaneous Adipose Tissues

Adipose tissue is a dynamic regulatory organ that has profound effects on the overall health of patients. Unfortunately, inconsistencies in human adipose tissues are extensive and multifactorial, including large variability in cellular sizes, lipid content, inflammation, extracellular matrix components, mechanics, and cytokines secreted. Given the high human variability, and since much of what is known about adipose tissue is from animal models, we sought to establish correlations and patterns between biological, mechanical, and epidemiological properties of human adipose tissues. To do this, twenty-six independent variables were cataloged for twenty patients, which included patient demographics and factors that drive health, obesity, and fibrosis. A factorial analysis for mixed data (FAMD) was used to analyze patterns in the dataset (with BMI > 25), and a correlation matrix was used to identify interactions between quantitative variables. Vascular endothelial growth factor A (VEGFA) and actin alpha 2, smooth muscle (ACTA2) gene expression were the highest loadings in the first two dimensions of the FAMD. The number of adipocytes was also a key driver of patient-related differences, where a decrease in the density of adipocytes was associated with aging. Aging was also correlated with a decrease in overall lipid percentage of subcutaneous tissue, with lipid deposition being favored extracellularly, an increase in transforming growth factor-β1 (TGFβ1), and an increase in M1 macrophage polarization. An important finding was that self-identified race contributed to variance between patients in this study, where Black patients had significantly lower gene expression levels of TGFβ1 and ACTA2. This finding supports the urgent need to account for patient ancestry in biomedical research to develop better therapeutic strategies for all patients. Another important finding was that TGFβ induced factor homeobox 1 (TGIF1), an understudied signaling molecule, which is highly correlated with leptin signaling, was correlated with metabolic inflammation. Furthermore, this study draws attention to what we define as "extracellular lipid droplets", which were consistently found in collagen-rich regions of the obese adipose tissues evaluated here. Reduced levels of TGIF1 were correlated with higher numbers of extracellular lipid droplets and an inability to suppress fibrotic changes in adipose tissue. Finally, this study indicated that M1 and M2 macrophage markers were correlated with each other and leptin in patients with a BMI > 25. This finding supports growing evidence that macrophage polarization in obesity involves a complex, interconnecting network system rather than a full switch in activation patterns from M2 to M1 with increasing body mass. Overall, this study reinforces key findings in animal studies and identifies important areas for future research, where human and animal studies are divergent. Understanding key drivers of human patient variability is required to unravel the complex metabolic health of unique patients.

Diabetes and Osteoarthritis: Exploring the Interactions and Therapeutic Implications of Insulin, Metformin, and GLP-1-Based Interventions

Diabetes mellitus (DM) and osteoarthritis (OA) are prevalent chronic conditions with shared pathophysiological links, including inflammation and metabolic dysregulation. This study investigates the potential impact of insulin, metformin, and GLP-1-based therapies on OA progression. Methods involved a literature review of clinical trials and mechanistic studies exploring the effects of these medications on OA outcomes. Results indicate that insulin, beyond its role in glycemic control, may modulate inflammatory pathways relevant to OA, potentially influencing joint health. Metformin, recognized for its anti-inflammatory properties via AMPK activation, shows promise in mitigating OA progression by preserving cartilage integrity and reducing inflammatory markers. GLP-1-based therapies, known for enhancing insulin secretion and improving metabolic profiles in DM, also exhibit anti-inflammatory effects that may benefit OA by suppressing cytokine-mediated joint inflammation and supporting cartilage repair mechanisms. Conclusions suggest that these medications, while primarily indicated for diabetes management, hold therapeutic potential in OA by targeting common underlying mechanisms. Further clinical trials are warranted to validate these findings and explore optimal therapeutic strategies for managing both DM and OA comorbidities effectively.

Interrelation of adipose tissue macrophages and fibrosis in obesity

Obesity is characterized by adipose tissue expansion, extracellular matrix remodelling and unresolved inflammation that contribute to insulin resistance and fibrosis. Adipose tissue macrophages represent the most abundant class of immune cells in adipose tissue inflammation and could be key mediators of adipocyte dysfunction and fibrosis in obesity. Although macrophage activation states are classically defined by the M1/M2 polarization nomenclature, novel studies have revealed a more complex range of macrophage phenotypes in response to external condition or the surrounding microenvironment. Here, we discuss the plasticity of adipose tissue macrophages (ATMs) in response to their microenvironment in obesity, with special focus on macrophage infiltration and polarization, and their contribution to adipose tissue fibrosis. A better understanding of the role of ATMs as regulators of adipose tissue remodelling may provide novel therapeutic strategies against obesity and associated metabolic diseases.

Adipose Tissue Dysfunction and the Role of Adipocyte-Derived Extracellular Vesicles in Obesity and Metabolic Syndrome

Obesity is a major public health issue that is associated with metabolic diseases including diabetes mellitus type 2 and metabolic syndrome. This pathology leads to detrimental cardiovascular health and secondary effects, such as lipotoxicity, inflammation, and oxidative stress. Recently, extracellular vesicles (EVs) have been highlighted as novel players participating in human physiology and pathophysiology. In obesity, adipose tissue is related to the active shedding of adipocyte-derived extracellular vesicles (AdEVs). The current review explores and highlights the role of AdEVs and their cargo in obesity and metabolic syndrome. AdEVs are proposed to play an important role in obesity and its comorbidities. AdEVs are biological nanoparticles mainly shed by visceral and subcutaneous adipose tissue, acting in physiological and pathophysiological conditions, and also carrying different cargo biomolecules, such as RNA, microRNA (miRNA), proteins, and lipids, among others. RNA and miRNA have local and systemic effects affecting gene expression in target cell types via paracrine and endocrine actions. State of the art analyses identified some miRNAs, such as miR-222, miR-23b, miR-4429, miR-148b, and miR-4269, that could potentially affect cell pathways involved in obesity-related comorbidities, such as chronic inflammation and fibrosis. Similarly, AdEVs-proteins (RBP4, perilipin-A, FABP, mimecan, TGFBI) and AdEVs-lipids (sphingolipids) have been linked to the obesity pathophysiology. The current knowledge about AdEVs along with further research would support and reveal novel pathways, potential biomarkers, and therapeutic options in obesity.

Huoxue Jiedu Huayu recipe inhibits macrophage-secreted vascular endothelial growth factor-a on angiogenesis and alleviates renal fibrosis in the contralateral kidneys of unilateral ureteral obstruction rats

OBJECTIVE：To elucidate the mechanism by which Huoxue Jiedu Huayu recipe (, HJHR) regulates angiogenesis in the contralateral kidney of unilateral ureteral obstruction (UUO) rats and the mechanism by which it reduces of renal fibrosis.

METHODS

Male Wistar rats were randomly divided into 4 groups: the sham group, UUO group (180 d of left ureter ligation), UUO plus eplerenone (EPL) group, and UUO plus HJHR group. After 180 d of oral drug administration, blood and contralateral kidneys were collected for analysis. Angiogenesis- and fibrosis-related indexes were detected.

RESULTS

HJHR and EPL improved structural damage and renal interstitial fibrosis in the contralateral kidney and reduced the protein expression levels of α-smooth muscle actin (α-SMA), vimentin and collagen I. Moreover, these treatments could reduce the expression of vascular endothelial growth factor-A (VEGFA) by inhibiting the infiltration of macrophages. Furthermore, HJHR and EPL significantly reduced the expression of CD34 and CD105 by downregulating VEGFA production, which inhibited angiogenesis. Finally, the coexpressions of CD34, CD105 and α-SMA were decreased in the HJHR and EPL groups, indicating that endothelial-to-mesenchymal transition was inhibited.

CONCLUSIONS

These findings confirm that HJHR alleviates contralateral renal fibrosis by inhibiting VEGFA-induced angiogenesis, encourage the use of HJHR against renal interstitial fibrosis and provide a theoretical basis for the clinical management of patients with CKD.

The endoplasmic reticulum stress protein GRP94 modulates cathepsin L activity in M2 macrophages in conditions of obesity-associated inflammation and contributes to their pro-inflammatory profile

BACKGROUND/OBJECTIVES

Adipose tissue macrophages (ATM) are key actors in the pathophysiology of obesity-related diseases. They have a unique intermediate M2-M1 phenotype which has been linked to endoplasmic reticulum (ER) stress. We previously reported that human M2 macrophages treated with the ER stress inducer thapsigargin switched to a pro-inflammatory phenotype that depended on the stress protein GRP94. In these conditions, GRP94 promoted cathepsin L secretion and was co-secreted with complement C3. As cathepsin L and complement C3 have been reported to play a role in the pathophysiology of obesity, in this work we studied the involvement of GRP94 in the pro-inflammatory phenotype of ATM.

METHODS

GRP94, cathepsin L and C3 expression were analyzed in CD206 + ATM from mice, WT or obesity-resistant transgenic fat-1, fed a high-fat diet (HFD) or a standard diet. GRP94 colocalization with cathepsin L and C3 and its effects were analyzed in human primary macrophages using thapsigargin as a control to induce ER stress and palmitic acid (PA) as a driver of metabolic activation.

RESULTS

In WT, but not in fat-1 mice, fed a HFD, we observed an increase in crown-like structures consisting of CD206 + pSTAT1+ macrophages showing high expression of GRP94 that colocalized with cathepsin L and C3. In vitro experiments showed that PA favored a M2-M1 switch depending on GRP94. This switch was prevented by omega-3 fatty acids. PA-induced GRP94-cathepsin L colocalization and a decrease in cathepsin L enzymatic activity within the cells (while the enzymatic activity in the extracellular medium was increased). These effects were prevented by the GRP94 inhibitor PU-WS13.

CONCLUSIONS

GRP94 is overexpressed in macrophages both in in vivo and in vitro conditions of obesity-associated inflammation and is involved in changing their profile towards a more pro-inflammatory profile. It colocalizes with complement C3 and cathepsin L and modulates cathepsin L activity.

Association between weight-adjusted-waist index and depression: a cross-sectional study

Background

Depression has become a multifaceted global health issue, with complex connections to obesity. Weight-adjusted-waist index (WWI) can effectively evaluate central obesity, but the relationship between WWI and depression has not been well studied. The study aims to investigate the potential correlation between these two health parameters.

Methods

According to the data from National Health and Nutrition Examination Survey, this cross-sectional study used multiple regression analysis, subgroup analysis, and smooth curve fitting to explore the relationship between WWI and depression. The assessment ability of WWI was evaluated and compared to other obesity indicators using the receiver operating characteristic (ROC) curve.

Results

This study analyzed 38,154 participants. Higher WWI is associated with higher depression scores (β = 0.41; 95% CI, 0.36-0.47). After adjusting for various confounding factors, the positive correlation between WWI and depression remained significant (P for trend < 0.0001). Nonlinear positive correlation was detected with a breakpoint of 11.14. ROC analysis shows that compared to other obesity indicators (ROCWWI = 0.593; ROCBMI = 0.584; and ROCWC = 0.581), the correlation between WWI and depression has better discrimination and accuracy. DII mediated 4.93%, SII mediated 5.08%, and sedentary mediated 0.35% of the total association between WWI and depression.

Conclusion

WWI levels were related to an increased likelihood of depression and showed a stronger relationship than BMI and waist circumference. Our findings indicated that WWI may serve as a simple anthropometric index to evaluate depression.

The signaling pathways in obesity-related complications

Obesity, a rapidly expanding epidemic worldwide, is known to exacerbate many medical conditions, making it a significant factor in multiple diseases and their associated complications. This threatening epidemic is linked to various harmful conditions such as type 2 diabetes mellitus, hypertension, metabolic dysfunction-associated steatotic liver disease, polycystic ovary syndrome, cardiovascular diseases (CVDs), dyslipidemia, and cancer. The rise in urbanization and sedentary lifestyles creates an environment that fosters obesity, leading to both psychosocial and medical complications. To identify individuals at risk and ensure timely treatment, it is crucial to have a better understanding of the pathophysiology of obesity and its comorbidities. This comprehensive review highlights the relationship between obesity and obesity-associated complications, including type 2 diabetes, hypertension, (CVDs), dyslipidemia, polycystic ovary syndrome, metabolic dysfunction-associated steatotic liver disease, gastrointestinal complications, and obstructive sleep apnea. It also explores the potential mechanisms underlying these associations. A thorough analysis of the interplay between obesity and its associated complications is vital in developing effective therapeutic strategies to combat the exponential increase in global obesity rates and mitigate the deadly consequences of this polygenic condition.

Harnessing IL-10 induced anti-inflammatory response in maturing macrophages in presence of electrospun dexamethasone-loaded PLLA scaffold

The ultimate goal of tissue engineering is to repair and regenerate damaged tissue or organ. Achieving this goal requires blood vessel networks to supply oxygen and nutrients to new forming tissues. Macrophages are part of the immune system whose behavior plays a significant role in angiogenesis and blood vessel formation. On the other hand, macrophages are versatile cells that change their behavior in response to environmental stimuli. Given that implantation of a biomaterial is followed by inflammation; therefore, we reasoned that this inflammatory condition in tissue spaces modulates the final phenotype of macrophages. Also, we hypothesized that anti-inflammatory glucocorticoid dexamethasone improves modulating macrophages behavior. To check these concepts, we investigated the macrophages that had matured in an inflammatory media. Furthermore, we examined macrophages' behavior after maturation on a dexamethasone-containing scaffold and analyzed how the behavioral change of maturing macrophages stimulates other macrophages in the same environment. In this study, the expression of pro-inflammatory markers TNFa and NFκB1 along with pro-healing markers IL-10 and CD163 were investigated to study the behavior of macrophages. Our results showed that macrophages that were matured in the inflammatory media in vitro increase expression of IL-10, which in turn decreased the expression of pro-inflammatory markers TNFa and NFκB in maturing macrophages. Also, macrophages that were matured on dexamethasone-containing scaffolds decreased the expression of IL-10, TNFa, and NFκB and increase the expression of CD163 compared to the control group. Moreover, the modulation of anti-inflammatory response in maturing macrophages on dexamethasone-containing scaffold resulted in increased expression of TNFa and CD163 by other macrophages in the same media. The results obtained in this study, proposing strategies to improve healing through controlling the behavior of maturing macrophages and present a promising perspective for inflammation control using tissue engineering scaffolds.

Genetic or pharmacological GHSR blockade has sexually dimorphic effects in rodents on a high-fat diet

The stomach-derived hormone ghrelin regulates essential physiological functions. The ghrelin receptor (GHSR) has ligand-independent actions; therefore, GHSR gene deletion may be a reasonable approach to investigate the role of this system in feeding behaviors and diet-induced obesity (DIO). Here, we investigate the effects of a long-term (12-month) high-fat (HFD) versus regular diet on obesity-related measures in global GHSR-KO and wild-type (WT) Wistar male and female rats. Our main findings are that the GHSR gene deletion protects against DIO and decreases food intake during HFD in male but not in female rats. GHSR gene deletion increases thermogenesis and brain glucose uptake in male rats and modifies the effects of HFD on brain glucose metabolism in a sex-specific manner, as assessed with small animal positron emission tomography. We use RNA-sequencing to show that GHSR-KO rats have upregulated expression of genes responsible for fat oxidation in brown adipose tissue. Central administration of a novel GHSR inverse agonist, PF-5190457, attenuates ghrelin-induced food intake, but only in male, not in female mice. HFD-induced binge-like eating is reduced by inverse agonism in both sexes. Our results support GHSR as a promising target for new pharmacotherapies for obesity.

Liraglutide improves adipose tissue remodeling and mitochondrial dynamics in a visceral obesity model induced by a high-fat diet

Central obesity is characterized by visceral adipose tissue (VAT) expansion, considered one of the main risk factors for metabolic complications. In recent years, new drugs have been studied for obesity treatment. Liraglutide (LGT), a GLP-1 agonist, decreases body weight, however, several mechanisms of action on VAT are still unknown.

Aim

to study the effect of LGT on factors associated with VAT remodeling and mitochondrial dynamics in mice fed a high-fat diet (HFD).

Methods

C57BL/6 mice were divided into Control (C) and HFD. After 15 weeks of feeding, each group was subdivided according to LGT administration for 5 weeks: C, C + LGT, HFD, and HFD + LGT. In epididymal AT (EAT) we evaluated histological and mitochondrial characteristics, vascularity, gelatinase activity (MMPs), and galectin-3 expression.

Results

HFD presented larger adipocytes (p < 0.05), and lower vascular density and MMP-9 activity (p < 0.01) than C, while a major number of smaller adipocytes (p < 0.05) and an increase in vascularity (p < 0.001) and MMP-9 activity (p < 0.01) was observed in HFD + LGT. Collagen content was higher (p < 0.05) in EAT from HFD and decreased in HFD + LGT. In C, C + LGT, and HFD + LGT, mitochondria were predominantly tubular-shaped while in HFD mitochondria were mostly spherical (p < 0.001).

Conclusion

LGT positively influences VAT behavior by modulating gelatinase activity, enhancing vascularization, and improving adipocyte histological characteristics. Additionally, LGT improves mitochondrial dynamics, a process that would favor VAT functionality.

Predicting major adverse cardiovascular events within 3 years by optimization of radiomics model derived from pericoronary adipose tissue on coronary computed tomography angiography: a case-control study

BACKGROUND

Coronary inflammation induces changes in pericoronary adipose tissue (PCAT) can be detected by coronary computed tomography angiography (CCTA). Our aim was to investigate whether different PCAT radiomics model based on CCTA could improve the prediction of major adverse cardiovascular events (MACE) within 3 years.

METHODS

This retrospective study included 141 consecutive patients with MACE and matched to patients with non-MACE (n = 141). Patients were randomly assigned into training and test datasets at a ratio of 8:2. After the robust radiomics features were selected by using the Spearman correlation analysis and the least absolute shrinkage and selection operator, radiomics models were built based on different machine learning algorithms. The clinical model was then calculated according to independent clinical risk factors. Finally, an overall model was established using the radiomics features and the clinical factors. Performance of the models was evaluated for discrimination degree, calibration degree, and clinical usefulness.

RESULTS

The diagnostic performance of the PCAT model was superior to that of the RCA-model, LAD-model, and LCX-model alone, with AUCs of 0.723, 0.675, 0.664, and 0.623, respectively. The overall model showed superior diagnostic performance than that of the PCAT-model and Cli-model, with AUCs of 0.797, 0.723, and 0.706, respectively. Calibration curve showed good fitness of the overall model, and decision curve analyze demonstrated that the model provides greater clinical benefit.

CONCLUSION

The CCTA-based PCAT radiomics features of three major coronary arteries have the potential to be used as a predictor for MACE. The overall model incorporating the radiomics features and clinical factors offered significantly higher discrimination ability for MACE than using radiomics or clinical factors alone.

Drug release profile of a novel exenatide long-term drug delivery system (OKV-119) administered to cats

Beneficial weight-loss properties of glucagon-like peptide-1 receptor agonists (GLP-1RA) in obese people, with corresponding improvements in cardiometabolic risk factors, are well established. OKV-119 is an investigational drug delivery system that is being developed for the long-term delivery of the GLP-1RA exenatide to feline patients. The purpose of this study was to evaluate the drug release characteristics of subcutaneous OKV-119 implants configured to release exenatide for 84 days. Following a 7-day acclimation period, five purpose-bred cats were implanted with OKV-119 protypes and observed for a 112-day study period. Food intake, weekly plasma exenatide concentrations and body weight were measured. Exenatide plasma concentrations were detected at the first measured timepoint (Day 7) and maintained above baseline for over 84 Days. Over the first 28 days, reduced caloric intake and a reduction in body weight were observed in four of five cats. In these cats, a body weight reduction of at least 5% was maintained throughout the 112-day study period. This study demonstrates that a single OKV-119 implant can deliver the GLP-1RA exenatide for a months long duration. Results suggest that exposure to exenatide plasma concentrations ranging from 1.5 ng/ml to 4 ng/ml are sufficient for inducing weight loss in cats.

Incorporation of Decidual Stromal Cells Derived Exosomes in Sodium Alginate Hydrogel as an Innovative Therapeutic Strategy for Advancing Endometrial Regeneration and Reinstating Fertility

Intrauterine adhesion (IUA) stands as a prevalent medical condition characterized by endometrial fibrosis and scar tissue formation within the uterine cavity, resulting in infertility and, in severe cases, recurrent miscarriages. Cell therapy, especially with stem cells, offers an alternative to surgery, but concerns about uncontrolled differentiation and tumorigenicity limit its use. Exosomes, more stable and immunogenicity-reduced than parent cells, have emerged as a promising avenue for IUA treatment. In this study, a novel approach has been proposed wherein exosomes originating from decidual stromal cells (DSCs) are encapsulated within sodium alginate hydrogel (SAH) scaffolds to repair endometrial damage and restore fertility in a mouse IUA model. Current results demonstrate that in situ injection of DSC-derived exosomes (DSC-exos)/SAH into the uterine cavity has the capability to induce uterine angiogenesis, initiate mesenchymal-to-epithelial transformation (MET), facilitate collagen fiber remodeling and dissolution, promote endometrial regeneration, enhance endometrial receptivity, and contribute to the recovery of fertility. RNA sequencing and advanced bioinformatics analysis reveal miRNA enrichment in exosomes, potentially supporting endometrial repair. This finding elucidates how DSC-exos/SAH mechanistically fosters collagen ablation, endometrium regeneration, and fertility recovery, holding the potential to introduce a novel IUA treatment and offering invaluable insights into the realm of regenerative medicine.

Vitamin D and the Metabolic Phenotype in Weight Loss After Bariatric Surgery: A Longitudinal Study

PURPOSE

To evaluate the influence of vitamin D (VD) concentrations coupled with metabolic phenotypes preoperatively and 6 months after Roux-en-Y gastric bypass (RYGB) on body variables and weight loss.

MATERIALS AND METHODS

A longitudinal, retrospective, analytical study comprising 30 adult individuals assessed preoperatively (T0) and 6 months (T1) after undergoing Roux-en-Y gastric bypass. The participants were distributed preoperatively into metabolically healthy obese (MHO) and metabolically unhealthy obese individuals (MUHO) according to the HOMA-IR classification, as well as the adequacy and inadequacy of vitamin D concentrations in the form of 25(OH)D. All participants were assessed for weight, height, body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), visceral adiposity index (VAI), body circularity index (BCI), body adiposity index (BAI), weight loss, and assessment of 25(OH)D and 1,25(OH)2D concentrations using high-performance liquid chromatography with an ultraviolet detector (HPLC-UV). The statistical program used was SPSS version 21.

RESULTS

VD adequacy and a healthy phenotype in the preoperative period may play an important role concerning body fat distribution, as the body averages for WHtR (0.020*) and BCI (0.020*) were lower in MHO participants. In comparison, those with VD inadequacy and MUHOs had higher BAI averages (0.000*) in the postoperative period. Furthermore, it is possible that VD inadequacy before and after RYGB, even in the presence of an unhealthy phenotype, may contribute to the increase in VAI values (0.029*) after this surgery. Only those with inadequate VD and MUHOs had higher 25(OH)D concentrations. Besides, this unhealthy phenotype had a greater reduction in BMI in the early postoperative period (p < 0.001).

CONCLUSION

This study suggests that VD adequacy and the presence of a healthy phenotype appear to have a positive impact on the reduction of visceral fat in the context of pre- and postoperative obesity. In addition, there was a greater weight reduction in those with VD inadequacy and in MUHO, which suggests that the volumetric dilution effect of VD and catabolism after bariatric surgery is more pronounced in this specific metabolic phenotype.

Multi-tissue profiling of oxylipins reveal a conserved up-regulation of epoxide:diol ratio that associates with white adipose tissue inflammation and liver steatosis in obesity

BACKGROUND

Obesity drives maladaptive changes in the white adipose tissue (WAT) which can progressively cause insulin resistance, type 2 diabetes mellitus (T2DM) and metabolic dysfunction-associated liver disease (MASLD). Obesity-mediated loss of WAT homeostasis can trigger liver steatosis through dysregulated lipid pathways such as those related to polyunsaturated fatty acid (PUFA)-derived oxylipins. However, the exact relationship between oxylipins and metabolic syndrome remains elusive and cross-tissue dynamics of oxylipins are ill-defined.

METHODS

We quantified PUFA-related oxylipin species in the omental WAT, liver biopsies and plasma of 88 patients undergoing bariatric surgery (female N = 79) and 9 patients (female N = 4) undergoing upper gastrointestinal surgery, using UPLC-MS/MS. We integrated oxylipin abundance with WAT phenotypes (adipogenesis, adipocyte hypertrophy, macrophage infiltration, type I and VI collagen remodelling) and the severity of MASLD (steatosis, inflammation, fibrosis) quantified in each biopsy. The integrative analysis was subjected to (i) adjustment for known risk factors and, (ii) control for potential drug-effects through UPLC-MS/MS analysis of metformin-treated fat explants ex vivo.

FINDINGS

We reveal a generalized down-regulation of cytochrome P450 (CYP)-derived diols during obesity conserved between the WAT and plasma. Notably, epoxide:diol ratio, indicative of soluble epoxide hydrolyse (sEH) activity, increases with WAT inflammation/fibrosis, hepatic steatosis and T2DM. Increased 12,13-EpOME:DiHOME in WAT and liver is a marker of worsening metabolic syndrome in patients with obesity.

INTERPRETATION

These findings suggest a dampened sEH activity and a possible role of fatty acid diols during metabolic syndrome in major metabolic organs such as WAT and liver. They also have implications in view of the clinical trials based on sEH inhibition for metabolic syndrome.

FUNDING

Wellcome Trust (PS3431_WMIH); Duke-NUS (Intramural Goh Cardiovascular Research Award (Duke-NUS-GCR/2022/0020); National Medical Research Council (OFLCG22may-0011); National Institute of Environmental Health Sciences (Z01 ES025034); NIHR Imperial Biomedical Research Centre.

New Mechanisms to Prevent Heart Failure with Preserved Ejection Fraction Using Glucagon-like Peptide-1 Receptor Agonism (GLP-1 RA) in Metabolic Syndrome and in Type 2 Diabetes: A Review

This review examines the impact of obesity on the pathophysiology of heart failure with preserved ejection fraction (HFpEF) and focuses on novel mechanisms for HFpEF prevention using a glucagon-like peptide-1 receptor agonism (GLP-1 RA). Obesity can lead to HFpEF through various mechanisms, including low-grade systemic inflammation, adipocyte dysfunction, accumulation of visceral adipose tissue, and increased pericardial/epicardial adipose tissue (contributing to an increase in myocardial fat content and interstitial fibrosis). Glucagon-like peptide 1 (GLP-1) is an incretin hormone that is released from the enteroendocrine L-cells in the gut. GLP-1 reduces blood glucose levels by stimulating insulin synthesis, suppressing islet α-cell function, and promoting the proliferation and differentiation of β-cells. GLP-1 regulates gastric emptying and appetite, and GLP-1 RA is currently indicated for treating type 2 diabetes (T2D), obesity, and metabolic syndrome (MS). Recent evidence indicates that GLP-1 RA may play a significant role in preventing HFpEF in patients with obesity, MS, or obese T2D. This effect may be due to activating cardioprotective mechanisms (the endogenous counter-regulatory renin angiotensin system and the AMPK/mTOR pathway) and by inhibiting deleterious remodeling mechanisms (the PKA/RhoA/ROCK pathway, aldosterone levels, and microinflammation). However, there is still a need for further research to validate the impact of these mechanisms on humans.