Adipose Tissue Inflammation Research Articles

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

ABSTRACT 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.

Circulating Cell-Free DNA in Metabolic Diseases

Abstract Metabolic diseases affect a consistent part of the human population, leading to rising mortality rates. This raises the need for diagnostic tools to monitor the progress of these diseases. Lately, circulating cell-free DNA (cfDNA) has emerged as promising biomarker for various metabolic diseases, including obesity, type 2 diabetes (T2D), and metabolic associated fatty liver disease (MAFLD). CfDNA is released from apoptotic and necrotic cells into the bloodstream and other body fluids, and it retains various molecular signatures of its tissue of origin. Thus, cfDNA load and composition can reflect tissue pathologies and systemic metabolic dysfunctions. In addition to its potential as diagnostic biomarker, interest in cfDNA derives from its recently discovered role in adipose tissue inflammation in obesity. This review discusses detection methods and clinical significance of cfDNA in metabolic diseases.

Effects of antidiabetic agents on lipid metabolism of skeletal muscle: A narrative review.

Metabolic syndrome-related diseases frequently involve disturbances in skeletal muscle lipid metabolism. The accumulation of lipid metabolites, lipid-induced mitochondrial stress in skeletal muscle cells, as well as the inflammation of adjacent adipose tissue, are associated with the development of insulin resistance and metabolic dysfunction. Consequently, when antidiabetic medications are used to treat various chronic conditions related to hyperglycaemia, the impact on skeletal muscle lipid metabolism should not be overlooked. However, current research has predominantly focused on muscle mass rather than skeletal muscle lipid metabolism and its interplay with glucose metabolism. In this review, we summarised the latest research on the effects of antidiabetic drugs and certain natural compounds with antidiabetic activity on skeletal muscle lipid metabolism, focusing on data from preclinical to clinical studies. Given the widespread use of antidiabetic drugs, a better understanding of their effects on skeletal muscle lipid metabolism merits further attention in future research.

Weight cycling exacerbates glucose intolerance and hepatic triglyceride storage in mice with a history of chronic high fat diet exposure

BackgroundObese subjects undergoing weight loss often fear the Yoyo dieting effect, which involves regaining or even surpassing their initial weight. To date, our understanding of such long-term obesity and weight cycling effects is still limited and often based on only short-term murine weight gain and loss studies. This study aimed to investigate the long-term impacts of weight cycling on glycemic control and metabolic health, focusing on adipose tissue, liver, and hypothalamus.MethodsChow-fed mice and mice subjected to prolonged high-fat diet (HFD) consumption for 20 weeks, followed by 24 weeks of dietary interventions to either induce weight gain, weight loss, or weight cycling were monitored for perturbations in feeding efficiency and glucose homeostasis. Post-mortem analyses included qPCR, Western Blotting, biochemical and microscopical assessments for hepatic steatosis and insulin resistance, hypothalamic and adipose tissue inflammation, and circulating lipid, leptin and IL-6 levels.ResultsWeight cycling led to hyperphagia and rapid weight regain, matching the weights of mice continuously on HFD. Despite weight loss, adipose tissue inflammation persisted with elevated pro-inflammatory markers, macrophage infiltration, and impaired Glut4 expression. HFD-induced dysregulation in hypothalamic expression of orexigenic peptides and synaptic plasticity markers persisted also after weight normalization suggesting long-lasting neural alterations. Weight-cycled mice exhibited higher circulating IL-6 and leptin levels, increased hepatic lipid storage, and dysregulated glucose metabolism compared to those with consistent diets, indicating worsened metabolic effects by Yoyo dieting.ConclusionIn sum, our study highlights significant metabolic risks associated with weight cycling, particularly following prolonged obesity. Persistent adipose tissue inflammation, perturbed neural peptide and plasticity markers and impaired glucose tolerance emphasize the need for effective and sustainable weight loss strategies to mitigate the adverse outcomes of weight regain and improve long-term metabolic health.

Mesenchymal Stem/Stromal Cells Reverse Adipose Tissue Inflammation in Pigs with Metabolic Syndrome and Renovascular Hypertension.

Metabolic syndrome (MetS) is associated with low-grade inflammation, which can be exacerbated by renal artery stenosis (RAS) and renovascular hypertension, potentially worsening outcomes through pro-inflammatory cytokines. This study investigated whether mesenchymal stem/stromal cells (MSCs) could reduce fat inflammation in pigs with MetS and RAS. Twenty-four pigs were divided into Lean (control), MetS, MetS + RAS, and MetS + RAS + MSCs. In the MSC-treated group, autologous adipose-derived MSCs (107 cells) were injected into the renal artery six weeks after RAS induction. After four weeks, fat volumes and inflammatory markers were assessed. MSC treatment reduced levels of pro-inflammatory cytokines (MCP-1, TNF-a, IL-6) in the renal vein blood and in perirenal fat. The MSCs also decreased fat fibrosis, restored adipocyte size, and altered adipogenesis-related gene expression, particularly in the perirenal fat. These effects were less pronounced in subcutaneous fat. The MSC therapy attenuated fat inflammation and improved metabolic outcomes in pigs with MetS + RAS, suggesting that adipose-derived MSCs may offer a promising therapeutic approach for metabolic disorders.

Amelioration of obesity-associated disorders by solanesol via mitigating NLRP3 inflammasome and macrophage inflammation in adipose tissue

Obesity and obesity-related metabolic diseases are causally linked to inflammatory activation. Proinflammatory macrophage infiltration and NLRP3 inflammasome activation contribute to chronic inflammation and insulin resistance. Alleviating inflammatory responses is a...

A dissociated glucocorticoid receptor modulator mitigates glucolipotoxicity in the endocrine pancreas and peripheral tissues: Preclinical data from a mouse model of diet-induced type 2 diabetes.

Type 2 diabetes (T2D) is a prevalent metabolic disease linked to obesity and metabolic syndrome (MS). The glucolipotoxic environment (GLT) impacts tissues causing low-grade inflammation, insulin resistance and the gradual loss of pancreatic β-cell function, leading to hyperglycemia. We have previously shown that Compound A (CpdA), a plant-derived dissociative glucocorticoid receptor-modulator with inflammation-suppressive activity, displays protective effects on β-cells in type 1 diabetes murine models. This study aimed to evaluate whether the administration of CpdA can attenuate GLT effects and improve pathophysiological parameters in a murine model of T2D/MS. Eight-week-old male C57BL/6NCrl mice were fed either a standard chow diet or a high-fat/high-sucrose diet (HFHS) for 15weeks. From week 5 of feeding, each group received i.p. injections of CpdA (2.5μg/g) or vehicle three times a week. We also examined CpdA in vitro effect against GLT using the insulinoma cell line INS-1E and naïve isolated mouse islets. CpdA administration in HFHS fed mice improved glucose homeostasis and insulin sensitivity with no apparent side effects. CpdA treatment also preserved pancreatic islet architecture and insulin expression, while reducing hepatic steatosis and visceral adipose tissue inflammation induced by HFHS diet. In vitro assays in INS-1E cells and naïve isolated mouse islets demonstrated that CpdA counteracted GLT-induced inhibition of glucose-stimulated insulin secretion and supported the expression of key β-cell identity genes under GLT conditions. These findings highlight the potential protective effect of CpdA in preserving β-cell functionality and peripheral tissue physiology in the context of T2D/MS.

LXR regulation of adipose tissue inflammation during obesity is associated with dysregulated macrophage function.

Liver X receptors (LXRs) play essential roles in cholesterol homeostasis and immune response. In obesity, elevated cholesterol levels trigger proinflammatory responses; however, the specific contributions of LXRs to adipose tissue (AT) macrophage (ATM) phenotype and metabolic programming are not fully understood. In this study, we determine the role of LXR isoforms in diet-induced obesity AT inflammation and insulin resistance. For in vivo studies, to evaluate the effects of LXR activation on AT inflammation, obese and insulin-resistant wild-type mice were treated with 10 mg/kg of the LXR modulator naringenin (NAR) for 4 weeks, and systemic insulin sensitivity and AT inflammation were assessed. To evaluate the effects of LXR deficiency on AT inflammation, we used LXRα, LXRβ, and LXRαβ knockout (KO) mice. For in vitro studies, to assess the role of LXRs specifically in macrophages, bone marrow-derived macrophages from wild-type, LXRαKO, LXRβKO, and LXRαβKO mice were treated with 0.5μM NAR 1 h prior to lipopolysaccharide (LPS) stimulation (100 ng/mL), and the effects on macrophage function and metabolism were evaluated 24 h after LPS stimulation. We found that LXR deletion intensifies AT inflammation in an LXRβ-dependent manner. LXR deficiency in immune cells exacerbates obesity-induced AT inflammation, increasing the numbers of CD11c+, TNF-α+, and IL-1β+ ATMs. We also identified NAR as a novel LXR agonist in macrophages that reduces proinflammatory cytokine secretion by mitigating glycolysis and mitochondrial dysfunction in LPS - and LPS + IFNγ-activated macrophages. Furthermore, NAR-treated obese mice display reduced AT inflammation, characterized by decreased CD11c+, IL-1β+, and TNF-α+ ATM numbers and monocyte infiltration compared with vehicle-treated obese mice. Our study highlights distinct roles for each LXR isoform in AT inflammation regulation, with LXRβ being crucial for maintaining the anti- and proinflammatory balance in ATMs. Thus, LXRβ holds therapeutic potential as a target to treat AT inflammation and insulin resistance.

Histone Deacetylase 9 Deletion Inhibits Hepatic Steatosis and Adipose Tissue Inflammation in Male Diet-Induced Obese Mice.

The goal of this study was to determine the role of histone deacetylase 9 (HDAC9) in the development of diet-induced metabolic dysfunction-associated steatohepatitis (MASH) and white adipose tissue (WAT) dysfunctions. We fed male and female mice with global Hdac9 knockout (KO) and their wild-type (WT) littermates an obesogenic high-fat/high-sucrose/high-cholesterol (35%/34%/2%, w/w) diet for 20 weeks. Hdac9 deletion markedly inhibited body weight gain and liver steatosis with lower liver weight and triglyceride content than WT in male mice but not females. Consistently, hepatic expression of genes crucial for de novo lipogenesis was markedly suppressed only in male, but not female, Hdac9 KO mice. However, Hdac9 deletion had a minimal effect on hepatic inflammation and fibrosis. In WAT, Hdac9 KO showed less adipocyte hypertrophy, inflammation, and fibrosis in male mice compared with WT. In addition, indirect calorimetry demonstrated that male Hdac9 KO mice had significantly higher metabolic rates, respiratory exchange ratios, and energy expenditure without altering physical activities than WT, which was not observed in female mice. Our findings indicate that global deletion of Hdac9 prevented the development of obesity, hepatic steatosis, and WAT inflammation and fibrosis in male mice with diet-induced obesity and MASH, suggesting that a sex-dependent role of HDAC9 may exist in the pathways mentioned above.

Spotlight on the Mechanism of Action of Semaglutide.

Initially intended to control blood glucose levels in patients with type 2 diabetes, semaglutide, a potent glucagon-like peptide 1 analogue, has been established as an effective weight loss treatment by controlling appetite. Integrating the latest clinical trials, semaglutide in patients with or without diabetes presents significant therapeutic efficacy in ameliorating cardiometabolic risk factors and physical functioning, independent of body weight reduction. Semaglutide may modulate adipose tissue browning, which enhances human metabolism and exhibits possible benefits in skeletal muscle degeneration, accelerated by obesity and ageing. This may be attributed to anti-inflammatory, mitochondrial biogenesis, antioxidant and autophagy-regulating effects. However, most of the supporting evidence on the mechanistic actions of semaglutide is preclinical, demonstrated in rodents and not actually confirmed in humans, therefore warranting caution in the interpretation. This article aims to explore potential innovative molecular mechanisms of semaglutide action in restoring the balance of several interlinking aspects of metabolism, pointing to distinct functions in inflammation and oxidative stress in insulin-sensitive musculoskeletal and adipose tissues. Moreover, possible applications in protection from infections and anti-aging properties are discussed. Semaglutide enhancement of the core molecular mechanisms involved in the progress of obesity and diabetes, although mostly preclinical, may provide a framework for future research applications in human diseases overall.

Bone marrow mesenchymal stem cells ameliorate diet-induced obesity by activating thermogenesis and alleviating inflammation in adipose tissue.

Obesity and its related metabolic disorders seriously threaten our health and significantly reduce our life expectancy. The aim of the present study was to explore the effects of bone marrow mesenchymal stem cells (BMSCs) on high-fat diet (HFD)-induced obesity mice. The results demonstrated that BMSCs significantly reduced body weight, improved glucose tolerance and insulin sensitivity in obese mice. Further analysis showed that BMSCs could promote brown adipose tissue (BAT) activity and white adipose tissue (WAT) browning by increasing the expression of mitochondrial uncouple protein 1 (UCP1). Additionally, BMSCs markedly increase mitochondrial biogenesis, activate oxidative phosphorylation (OXPHOS) in adipose tissue, further contributing to energy metabolism regulation. Moreover, BMSCs were effective in inhibiting macrophage-related inflammation in adipose tissue, thereby mitigating obesity-associated inflammatory responses. Overall, our results lay the foundation for research on the potential of BMSCs as a promising strategy in alleviating obesity and related metabolic diseases.

Increased expression levels of PIEZO1 in visceral adipose tissue in obesity and type 2 diabetes are triggered by mechanical forces and are associated with inflammation

BackgroundPIEZO1 has emerged as a mechanoreceptor linked with adipogenesis, adipose tissue (AT) inflammation and insulin resistance. We aimed to determine the impact of obesity and obesity-associated type 2 diabetes (T2D) as well as mechanical compression forces on the expression of PIEZO1 in visceral AT (VAT) and its relation with inflammation.MethodsBlood and VAT samples were obtained from 100 volunteers. Static compression studies in VAT explants were performed to study the PIEZO1 response. The effect of bariatric surgery on the expression of Piezo1 was assessed in a rat model of diet-induced obesity.ResultsObesity and obesity-associated T2D increased (P < 0.01) gene expression levels of PIEZO1 in VAT mainly due to adipocytes. SWELL1 and key markers of inflammation (NLRP3, NLRP6, IL1B, IL18 and IL8) were also upregulated in VAT in obesity and T2D being significantly associated (P < 0.01) with PIEZO1 levels. We further showed that the static compression of VAT explants promoted an upregulation of PIEZO1 (P < 0.01) and SWELL1 (P < 0.01) expression levels together with a strong increase in the expression and release of key inflammatory mediators. The treatment of THP-1-derived macrophages with the secretome of adipocytes from patients with obesity upregulated (P < 0.001) PIEZO1 levels. Rats undergoing bariatric surgery exhibited decreased (P < 0.01) expression levels of Piezo1 in the epididymal AT.ConclusionsStatic compression triggered an upregulation of PIEZO1 in VAT explants together with a strong inflammation. In addition, the increased expression of PIEZO1 in VAT in obesity and obesity-associated T2D, primarily attributable to adipocytes, is closely associated with SWELL1 and inflammatory markers.

Exploring CTRP6: a biomarker and therapeutic target in metabolic diseases.

The rising prevalence of metabolic diseases is a significant global health concern. Beyond lifestyle management, targeting key molecules involved in metabolic regulation is essential. C1q/TNF-related protein 6 (CTRP6) is notably associated with glucose and lipid metabolism, with numerous studies highlighting its regulatory functions in metabolic diseases. This review summarizes the current knowledge on CTRP6, focusing on its gene expression profiles, protein structure, gene regulation, and role in metabolic diseases. CTRP6 is widely expressed across various tissues and features four distinct domains, with the C1q domain predicted to bind to its receptor. Notably, serum levels of CTRP6 are significantly elevated in patients with obesity and type 2 diabetes. In these conditions, adipose tissue serves as a key source of CTRP6, and its involvement in adipose tissue expansion, inflammation, and nutrient sensing has been observed in several studies. CTRP6 is also implicated in type 1 diabetes, gestational diabetes mellitus, and diabetic complications, particularly diabetic nephropathy. Although some studies have suggested that CTRP6 has protective roles in atherosclerotic cell models, myocardial infarction rat models, and ischemia/reperfusion injury mouse models, methodological issues such as unreliable antibodies and unstrict controls make it difficult to draw accurate conclusions from these studies. Patients with polycystic ovary syndrome (PCOS) exhibit elevated serum levels of CTRP6, though its direct impact on PCOS phenotypes remains unclear. In conclusion, CTRP6 emerges as a promising therapeutic target for metabolic diseases. A deeper understanding of CTRP6 will empower the scientific community to develop effective interventions to address the increasing prevalence of these diseases.

Pediococcus acidilactici Y01 reduces HFD-induced obesity via altering gut microbiota and metabolomic profiles and modulating adipose tissue macrophage M1/M2 polarization.

Obesity-related metabolic syndrome is intimately associated with infiltrated adipose tissue macrophages (ATMs), gut microbiota, and metabolic disorders. Pediococcus acidilactici holds the potential to mitigate obesity; however, there exist strain-specific functionalities and diverse mechanisms, which deserve extensive exploration. This study aims to explore the potential of P. acidilactici Y01, isolated from traditional sour whey, in alleviating HFD-induced metabolic syndrome in mice and elucidating its underlying mechanism. The results showed that P. acidilactici Y01 could inhibit the increase of body weight gain, the deposition of fat, lipid disorders and chronic low-grade inflammation, improve glucose tolerance and insulin resistance, and could reduce adipose tissue inflammation by decreasing M1-type ATMs and increasing M2-type ATMs. Meanwhile, P. acidilactici Y01 significantly increased the abundance of potentially beneficial intestinal bacteria, such as Akkermansia, Alistipes, Bifidobacterium, Lachnospiraceae_NK4A136_group, Lactobacillus, norank_f__Muribaculaceae, and Parabacteroides, and partially restored the levels of metabolites, such as phosphatidylcholines, glycerophosphocholines, sphingolipids and unsaturated fatty acids. The fecal microbiota transplantation experiment demonstrated that P. acidilactici Y01 ameliorated obesity-related metabolic syndrome by modulating the polarization of M1/M2 ATMs mediated by gut microbiota. Overall, as a dietary supplement, P. acidilactici Y01 has good potential in the prevention and treatment of obesity.

Sex differentially affects pro-inflammatory cell subsets in adipose tissue depots in a diet induced obesity model

Obesity is a growing pandemic that increases the risk for cardiovascular diseases, type 2 diabetes, and particularly in women also the risk of cancer and neurodegenerative disorders such as dementia and multiple sclerosis. Preclinical studies on obesity focus on male mice as they gain bodyweight faster and show a clear pro-inflammatory phenotype. Here, using male and female mice, we induced obesity by feeding a high fat diet (HFD), and compared adipose tissue (AT) inflammation at the same adiposity stage (% AT/bodyweight) between both sexes. Doing so, we identified that female mice show an increase in the number of pro-inflammatory immune cells in the visceral AT at a lower adiposity stage than male mice, but the effect of HFD is diminished with higher adiposity. Interestingly, only female mice showed an increase in immune cells in the subcutaneous AT after HFD feeding. Nonetheless, we found that pro-inflammatory cytokines in blood plasma mirror the inflammatory stage of the visceral AT in both male and female mice. Uniquely in male mice, myeloid cells in the visceral AT showed a higher inflammasome activation upon HFD. In summary, we showed that adiposity differentially affects immune cells in fat depots based on sex.

Lactobacillus reuteri-Enriched Eicosatrienoic Acid Regulates Glucose Homeostasis by Promoting GLP-1 Secretion to Protect Intestinal Barrier Integrity.

Lactobacillus reuteri is a well-known probiotic with beneficial effects, such as anti-insulin resistance, anti-inflammatory, and improvement of the intestinal barrier. However, the underlying mechanisms remain unclear. Here, we found that gavage of L. reuteri improved the intestinal barrier and glucose homeostasis in HFD-fed mice. Analysis of lipid metabolomics reveals a significant increase in eicosatrienoic acid (ETA) levels in mouse feces after L. reuteri gavage. We found that ETA maintain intestinal barrier integrity and improve glucose homeostasis by promoting GLP-1 secretion. Mechanistically, by using CD36 inhibitor in vivo and CD36 knockdown STC-1 cells in vitro, we elucidate that ETA activates intestinal CD36-activated PLC/IP3R/Ca2+ signaling to promote GLP-1 secretion. In vivo administration of GLP-1R inhibitor and in vitro intestinal organoid experiments demonstrate that GLP-1 upregulates the PI3K/AKT/HIF-1α pathway by GLP-1R and increases intestinal tight junction protein expressions, which in turn enhance the intestinal barrier integrity, reduce serum LPS level, attenuate inflammation in white adipose tissue (WAT), and ultimately improve glucose homeostasis in HFD and db/db mice. Our study elucidates for the first time the mechanism by which L. reuteri and its enriched metabolite ETA inhibit WAT inflammation by ameliorating the intestinal barrier, ultimately improving glucose homeostasis, and provides a new treatment strategy for T2D.

Brown Rice: A Promising Therapeutic Strategy for Reducing Inflammatory Markers in the Adipose Tissue of Diet-Induced Obesity Rat Model

Obesity is closely linked to adipose tissue inflammation, where macrophages play a crucial role. One approach to enhance the issue of obesity is by implementing nutritional intervention. This study designed to investigate the impact of administering brown rice and gamma oryzanol (ORZ) on reducing adipose tissue expansion and inflammation in a rat model of diet-induced obesity. The study involved male Sprague-Dawley rats of the Rattus novergicus strain. The negative control group received AIN93M as the standard diet, while the remaining were induced to become obese by high-fat, high fructose (HFHFr) diet. Then, we divided them into 4 treatment groups: mix HFHFr diet with brown rice; white rice; white rice + ORZ; and ORZ only. Treatment was given for 12 weeks. Histological examination was used to measure both the size and number of adipocytes. Immunohistochemical staining was done to evaluate the infiltration of macrophages into adipose tissue, while immunofluorescence labelling was utilized to examine the expression of macrophages M1 and M2. The addition of brown rice and ORZ appears to improve adipocyte expansion. The brown rice group showed the least amount of M1 macrophages, while the negative control group showed the highest amount of M2 macrophages, leading to much lower M1/M2 ratios compared to the other groups. No differences were found in the study of variables in either visceral or subcutaneous adipose tissue. Brown rice and ORZ can potentially improve adipose tissue expansion and suppress the expression of pro-inflammatory macrophages.

Fanlian Huazhuo Formula: A promising herbal preparation for metabolic liver disease.

The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) has increased significantly in recent decades and is projected to increase further due to the rising obesity rates. MASLD patients are at higher risk of developing advanced liver diseases "cirrhosis and hepatocellular carcinoma" as well as liver- or cardiovascular-related mortality. Existing lipid-lowering therapies failed to reduce the risk of mortality in these patients. Therefore, there is an urgent need for pharmacotherapies that can control and even reverse this disease. Fanlian Huazhuo Formula (FLHZF) is a combination herbal preparation, and its various individual constituents regulate hepatic lipid metabolism, adipose tissue inflammation, and gut microbiota. Despite, these useful effects, limited information is available on its benefits in diet-induced hepatosteatosis. In this article, we discuss the research findings recently published about the therapeutic effects of FLHZF in suppressing MASLD development and underlying mechanisms. Utilizing a series of in vitro and in vivo experiments, the authors demonstrated for the first time that FLHZF suppresses MASLD in male mice possibly by inhibiting hepatic de novo lipogenesis pathways and reducing hepatocyte death. This study paves the way for future investigations aimed at investigating FLHZF's role in inhibiting lipogenesis particularly using radioactively-labeled glucose and acetate, and governing hepatocyte mitochondrial function, gut microbiome profile, and its effects in other models of MASLD, and female mice.

Metabolic dysfunction-associated steatotic liver disease: heterogeneous pathomechanisms and effectiveness of metabolism-based treatment.

The global epidemic of metabolic dysfunction-associated steatotic liver disease (MASLD) is increasing worldwide. People with MASLD can progress to cirrhosis and hepatocellular carcinoma and are at increased risk of developing type 2 diabetes, cardiovascular disease, chronic kidney disease, and extrahepatic cancers. Most people with MASLD die from cardiac-related causes. This outcome is attributed to the shared pathogenesis of MASLD and cardiometabolic diseases, involving unhealthy dietary habits, dysfunctional adipose tissue, insulin resistance, and subclinical inflammation. In addition, the steatotic and inflamed liver affects the vasculature and heart via increased glucose production and release of procoagulant factors, dyslipidaemia, and dysregulated release of hepatokines and microRNAs. However, there is substantial heterogeneity in the contributors to the pathophysiology of MASLD, which might influence its rate of progression, its relationship with cardiometabolic diseases, and the response to therapy. The most effective non-pharmacological treatment approaches for people with MASLD include weight loss. Paradoxically, some effective pharmacological approaches to improve liver health in people with MASLD are associated with no change in bodyweight or even with weight gain, and similar response heterogeneity has been observed for changes in cardiometabolic risk factors. In this Review, we address the heterogeneity of MASLD with respect to its pathogenesis, outcomes, and metabolism-based treatment responses. Although there is currently insufficient evidence for the implementation of precision medicine for risk prediction, prevention, and treatment of MASLD, we discuss whether knowledge about this heterogeneity might help achieving this goal in the future.

P102 Importance of the inflammation in adipose tissue as exacerbating factor of obesity-associated psoriasis

Abstract Obesity is a risk factor for psoriasis. However, it is not necessarily detrimental when excess fat is stored in healthy adipose tissue. To identify pathogenic association between obesity and psoriasis, we investigated an obese mouse model of psoriasis induced by topical imiquimod or dermal interleukin (IL)-23 injection. Obese mice exhibited aggravated psoriatic dermatitis with pronounced systemic inflammatory responses when exposed to imiquimod. Notably, imiquimod-induced psoriatic dermatitis in obese mice significantly reduced fat mass. Further, pronounced monocyte–macrophage infiltration of perigonadal adipose tissue, increased expression of genes linked to inflammation, and upregulation of cell death-associated molecules were evident in obese mice treated with imiquimod compared with their lean counterparts. In contrast, IL-23 injection could induce similar features of psoriatic inflammation in obese and lean mice, without causing adipose tissue destruction or a systemic increase in inflammatory mediators. Obese adipose tissue of mice with imiquimod-induced psoriatic inflammation featured genetic and epigenetic changes in adipocytes and shifts in macrophage compartments towards disturbed homeostasis using multiomic single-nucleus sequencing targeting RNA and accessible chromatin. Our study demonstrates that disrupted homeostasis in obese adipose tissue amplifies the systemic manifestations of psoriasis, highlighting the potential for developing interventions to control obesity-associated exacerbation of psoriasis.