Immune regulation of metabolic homeostasis in health and disease

Legumain-deficient macrophages regulate inflammation and lipid metabolism in adipose tissues to protect against diet-induced obesity

Adipose tissue macrophages (ATMs) are key players in the development of obesity and associated metabolic inflammation, which contributes to systemic metabolic dysfunction, and understanding the interaction between macrophages and adipocytes is crucial for developing novel macrophage-based strategies against obesity. Here, we found that Legumain (Lgmn), a well-known lysosomal cysteine protease, is expressed mainly in the ATMs of obese mice. To further define the potential role of Lgmn-expressing macrophages in the generation of an aberrant metabolic state, LgmnF/F; LysMCre mice, which do not express Lgmn in macrophages, were maintained on a high-fat diet (HFD), and metabolic parameters were assessed. Macrophage-specific Lgmn deficiency protects mice against HFD-induced obesity, diminishes the quantity of proinflammatory macrophages in obese adipose tissues, and alleviates hepatic steatosis and insulin resistance. By analysing the transcriptome and proteome of murine visceral white adipose tissue (vWAT) after HFD feeding, we determined that macrophage Lgmn deficiency causes changes in lipid metabolism and the inflammatory response. Furthermore, the reciprocity of macrophage-derived Lgmn with integrin α5β1 in adipocytes was tested via colocalization analyses. It is further demonstrated in macrophage and adipocyte coculture system that macrophage derived Lgmn bound to integrin α5β1 in adipocytes, therefore attenuating PKA activation, downregulating lipolysis-related proteins and eventually exacerbating obesity development. Overall, our study identified Lgmn as a previously unrecognized regulator involved in the interaction between ATMs and adipocytes contributing to diet-induced obesity and suggested that Lgmn is a potential target for treating metabolic disorders.

PDIA3 defines a novel subset of adipose macrophages to exacerbate the development of obesity and metabolic disorders

Adipose tissue macrophages (ATMs) play important roles in maintaining adipose tissue homeostasis and orchestrating metabolic inflammation. Given the extensive functional heterogeneity and phenotypic plasticity of ATMs, identification of the authentically pathogenic ATM subpopulation under obese setting is thus necessitated. Herein, we performed single-nucleus RNA sequencing (snRNA-seq) and unraveled a unique maladaptive ATM subpopulation defined as ATF4hiPDIA3hiACSL4hiCCL2hi inflammatory and metabolically activated macrophages (iMAMs), in which PDIA3 is required for the maintenance of their migratory and pro-inflammatory properties. Mechanistically, ATF4 serves as a metabolic stress sensor to transcribe PDIA3, which then imposes a redox control on RhoA activity and strengthens the pro-inflammatory and migratory properties of iMAMs through RhoA-YAP signaling. Administration of Pdia3 small interfering RNA (siRNA)-loaded liposomes effectively repressed adipose inflammation and high-fat diet (HFD)-induced obesity. Together, our data support that strategies aimed at targeting iMAMs by suppressing PDIA3 expression or activity could be a viable approach against obesity and metabolic disorders in clinical settings.

Subcutaneous adipose tissue: Implications in dermatological diseases and beyond

Subcutaneous adipose tissue (SAT) is the deepest component of the three-layered cutaneous integument. While mesenteric adipose tissue-based immune processes have gained recognition in the context of the metabolic syndrome, SAT has been traditionally considered primarily for energy storage, with less attention to its immune functions. SAT harbors a reservoir of immune and stromal cells that significantly impact metabolic and immunologic processes not only in the skin, but even on a systemic level. These processes include wound healing, cutaneous and systemic infections, immunometabolic, and autoimmune diseases, inflammatory skin diseases, as well as neoplastic conditions. A better understanding of SAT immune functions in different processes, could open avenues for novel therapeutic interventions. Targeting SAT may not only address SAT-specific diseases but also offer potential treatments for cutaneous or even systemic conditions. This review aims to provide a comprehensive overview on SAT's structure and functions, highlight recent advancements in understanding its role in both homeostatic and pathological conditions within and beyond the skin, and discuss the main questions for future research in the field.

Adipocyte-Targeted Nanocomplex with Synergistic Photothermal and Pharmacological Effects for Combating Obesity and Related Metabolic Syndromes

Obesity is a global epidemic which induces a multitude of metabolic disorders. Browning of white adipose tissue (WAT) has emerged as a promising therapeutic strategy for promoting weight loss and improving associated metabolic syndromes in people with obesity. However, current methods of inducing white adipose tissue browning have limited applicability. We developed a nanocomplex pTSL@(P+I), which is a temperature-sensitive liposome (TSL) surface-conjugated with an adipocyte-targeting peptide (p) and loaded with both browning-promoting agents (P) and photosensitizing agents (I). This nanocomplex exhibits adipocyte targeting, as well as synergistic pharmacological and photothermal properties to promote browning. pTSL@(P+I) effectively upregulates UCP1 and COX5B expression by activating the transcription axis of PPARγ/PGC1α and HSF1/PGC1α, thereby promoting white adipose tissue browning and reducing obesity. This novel nanocomplex exhibited a uniform spherical shape, with an average diameter of approximately 200 nm. Additionally, the nanocomplexes exhibited remarkable photothermal properties and biocompatibility. Further, when adipocytes were treated with pTSL@(P+I), their triglyceride content decreased remarkably and intracellular mitochondrial activity increased significantly. When applied to diet-induced obesity (DIO) mice, the nanocomplex exhibited significant efficacy, demonstrating a notable 14.4% reduction in body weight from the initial measurement, a decreased fat/lean mass ratio of 20.8%, and no statistically significant disparities (p > 0.05) in associated side effects when compared to the control group. In summary, implementation of the targeted nanocomplex pTSL@(P+I) to enhance energy expenditure by stimulating white adipose tissue browning offers a promising therapeutic approach for the treatment of obesity and related metabolic syndromes.

Lesson on obesity and anatomy of adipose tissue: new models of study in the era of clinical and translational research

Obesity is a serious global illness that is frequently associated with metabolic syndrome. Adipocytes are the typical cells of adipose organ, which is composed of at least two different tissues, white and brown adipose tissue. They functionally cooperate, interconverting each other under physiological conditions, but differ in their anatomy, physiology, and endocrine functions. Different cellular models have been proposed to study adipose tissue in vitro. They are also useful for elucidating the mechanisms that are responsible for a pathological condition, such as obesity, and for testing therapeutic strategies. Each cell model has its own characteristics, culture conditions, advantages and disadvantages. The choice of one model rather than another depends on the specific study the researcher is conducting. In recent decades, three-dimensional cultures, such as adipose spheroids, have become very attractive because they more closely resemble the phenotype of freshly isolated cells. The use of such models has developed in parallel with the evolution of translational research, an interdisciplinary branch of the biomedical field, which aims to learn a scientific translational approach to improve human health and longevity. The focus of the present review is on the growing body of data linking the use of new cell models and the spread of translational research. Also, we discuss the possibility, for the future, to employ new three-dimensional adipose tissue cell models to promote the transition from benchside to bedsite and vice versa, allowing translational research to become routine, with the final goal of obtaining clinical benefits in the prevention and treatment of obesity and related disorders.

Association between obesity and systemic immune inflammation index, systemic inflammation response index among US adults: a population-based analysis

BACKGROUND

Obesity is characterized by a chronic low-grade inflammatory condition. Two emerging inflammatory biomarkers, the systemic immune-inflammation index (SII) and the systemic inflammation response index (SIRI), have gained attention. However, the relationships between obesity and SII/SRI remain unclear.

METHODS

In this study, we analyzed data from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2018 among adults. SII-SIRI/SII/SIRI were categorized into three groups based on tertiles. The association between obesity and SII-SIRI/SII/SIRI was assessed by multivariable logistic regression models. Restricted cubic spline (RCS) plots were used to examine the nonlinear association between obesity and SII/SIRI. Finally, potential independent associations between obesity and SII/SIRI were further explored using subgroup analyses.

RESULTS

The study included 20,011 adults, of whom 7,890 (39.32%) were obesity. In model 1, participants in the high (Q3) level of SII-SIRI had a significantly association with obesity than those in the low (Q1) level group. The high level of SII and SIRI were positively associated with obesity as compared to low levels. Model 2 revealed a positive association between obesity and high levels of SII-SIRI/SII/SIRI. Model 3 demonstrated a similar trend. RCS curves revealed a nonlinear association linking obesity to SII/SIRI. Subgroup analysis showed an interaction between SII/SIRI and age.

CONCLUSIONS

Our research suggested that obesity was positively associated with SII-SIRI/SII/SIRI in U.S. adults. SII/SIRI may represent a cost-effective and direct approach to assessing obesity.

Graphene oxide-decorated microporous sulfonated polyetheretherketone for guiding osteoporotic bone regeneration

Recent studies have indicated that the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome is an ideal therapeutic target for osteoporosis because it affects the differentiation of osteoblasts and osteoclasts. RNA sequencing utilizing multifunctional graphene oxide (GO) nanosheets revealed a correlation between GO nanomaterials and the NLRP3 inflammasome, as well as osteogenic genes in macrophages. This study aimed to construct a bone microenvironment-responsive multifunctional two-dimensional GO coating on the surface of microporous sulfonated polyetheretherketone (SPEEK) via polydopamine modification (SPEEK@PDA-GO). In vitro analysis showed that the SPEEK@PDA-GO implants weakened the STAT3-mediated NLRP3/caspase-1/IL-1β signaling pathway in macrophages and subsequently prevented the formation of an extracellular inflammatory microenvironment, which is crucial for osteoclastogenesis. SPEEK@PDA-GO displayed significantly higher expression of M2 macrophage markers and osteogenic genes, indicating that the multifunctional GO nanosheets could facilitate bone regeneration via their immunomodulatory properties. The ability of SPEEK@PDA-GO to stimulate new bone formation and block bone loss caused by estrogen loss due to ovariectomy was also analyzed. The findings of this study offer valuable information on the possible involvement of the NLRP3 inflammasome in the interaction between the immune system and bone health in patients with osteoporosis.

Macrophage polarization as a novel endpoint for assessing combined risk of phthalate esters

Combined exposure to phthalate esters (PAEs) has garnered increasing attention due to potential synergistic effects on human health. This study aimed to develop an in vitro model using human macrophages to evaluate the combined toxicity of PAEs and explore the underlying mechanisms. A high-throughput screening system was engineered by expressing a PPRE-eGFP reporter in THP-1 monocytes to monitor macrophage polarization upon PAEs exposure. Individual PAEs exhibited varied inhibitory effects on M2 macrophage polarization, with mono(2-ethylhexyl) phthalate (MEHP) being the most potent. Isobologram analysis revealed additive interactions when MEHP was combined with other PAEs, resulting in more pronounced suppression of M2 markers compared to individual compounds. Mechanistic studies suggested PAEs may exert effects by modulating PPARγ activity to inhibit M2 polarization. Notably, an equimolar mixture of six PAEs showed additive inhibition of M2 markers. In vivo experiments corroborated the combined hepatotoxic effects, with mice exposed to a PAEs mixture exhibiting reduced liver weight, dyslipidemia, and decreased hepatic M2 macrophages compared to DEHP alone. Transcriptome analysis highlighted disruptions in PPAR signaling, and distinct pathway alterations on cholesterol metabolism in the mixture group. Collectively, these findings underscore the importance of evaluating mixture effects and provide a novel approach for hazard assessment of combined PAEs exposure with implications for environmental health risk assessment.

Thymic stromal lymphopoietin induces IL-4/IL-13 from T cells to promote sebum secretion and adipose loss

BACKGROUND

The cytokine TSLP promotes type 2 immune responses and can induce adipose loss by stimulating lipid loss from the skin through sebum secretion by sebaceous glands, which enhances the skin barrier. However, the mechanism by which TSLP upregulates sebaceous gland function is unknown.

OBJECTIVES

This study investigated the mechanism by which TSLP stimulates sebum secretion and adipose loss.

METHODS

RNA-sequencing analysis was performed on sebaceous glands isolated by laser capture microdissection and single-cell RNA-sequencing analysis was performed on sorted skin T cells. Sebocyte function was analyzed by histological analysis and sebum secretion in vivo and by measuring lipogenesis and proliferation in vitro.

RESULTS

This study found that TSLP sequentially stimulated the expression of lipogenesis genes followed by cell death genes in sebaceous glands to induce holocrine secretion of sebum. TSLP did not affect sebaceous gland activity directly. Rather, single-cell RNA-sequencing revealed that TSLP recruited distinct T-cell clusters that produce IL-4 and IL-13, which were necessary for TSLP-induced adipose loss and sebum secretion. Moreover, IL-13 was sufficient to cause sebum secretion and adipose loss in vivo and to induce lipogenesis and proliferation of a human sebocyte cell line in vitro.

CONCLUSIONS

This study proposes that TSLP stimulates T cells to deliver IL-4 and IL-13 to sebaceous glands, which enhances sebaceous gland function, turnover, and subsequent adipose loss.

Integrated analysis of omics reveals the role of scapular fat in thermogenesis adaptation in sunite sheep

Inhabiting some of the world's most inhospitable climatic regions, the Sunite Mongolian sheep generates average temperatures as low as 4.3 °C and a minimum temperature of -38.8 °C; in these environments, they make essential cold adaptations. In this regard, scapular fat tissues from Mongolian sheep were collected both in winter and summer for transcriptomic and proteomic analyses to identify genes related to adaptive thermogenesis. In the transcriptome analysis, 588 differentially expressed genes were identified to participate in smooth muscle activity and fat metabolism, as well as in nutrient regulation. There were 343 upregulated and 245 downregulated genes. GO and KEGG pathway analyses on these genes revealed their participation in regulating smooth muscle activity, metabolism of fats, and nutrients. Proteomic analysis showed the differential expression of 925 proteins: among them, there are 432 up- and 493 down-expressed proteins. These proteins are mainly involved in oxidative phosphorylation, respiratory chain complex assembly, and ATP production by electron transport. Furthermore, using both sets at a more detailed level of analysis revealed over-representation in gene ontology categories related to hormone signaling, metabolism of lipids, the pentose phosphate pathway, the TCA cycle, and especially the process of oxidative phosphorylation. The identified essential genes and proteins were further validated by quantitative real-time polymerase chain reaction and Western blotting, respectively; key metabolic network constriction was constructed. The present study emphasized the critical role of lipid turnover in scapular fat for thermogenic adaptation in Sunite sheep.

Sema-3E/PlexinD1 axis modulates dendritic cell phenotypes and functions: Current status and future implications

This comprehensive research review explores the complex interplay between the Sema-3E/PlexinD1 axis and dendritic cells (DCs), highlighting its critical role in immune modulation with implications for clinical application Critical regulators of immune responses Dendritic cells are central to adaptive immunity, and the Sema-3E /PlexinD1 axis emerges as a key modulator affecting their phenotypes and functions Review delineates the impact of this signaling axis on DC maturation, migration, antigen presentation, and cytokine production, unravels its multifaceted role in shaping the immune response. Recognizing the limitations and gaps in current knowledge, the study highlights the need for further studies to condition downstream signaling events and related information experienced by the Sema-3E/PlexinD1 axis emphasizes the clarity of the immune system. The review concludes by identifying opportunities for translation, focusing on therapeutic and diagnostic potential. It highlights the importance of collaborative, interdisciplinary efforts to address the challenges and harness the therapeutic and pathological potential of targeting the Sema-3E/PlexinD1 axis, thus opening the way for transformative advances in immunology and clinical medicine.

Adipose-derived extracellular vesicles - a novel cross-talk mechanism in insulin resistance, non-alcoholic fatty liver disease, and polycystic ovary syndrome

Obesity is the best described risk factor for the development of non-alcoholic fatty liver disease (NAFLD)/metabolic dysfunction associated steatotic liver disease (MASLD) and polycystic ovary syndrome (PCOS) while the major pathogenic mechanism linking these entities is insulin resistance (IR). IR is primarily caused by increased secretion of proinflammatory cytokines, adipokines, and lipids from visceral adipose tissue. Increased fatty acid mobilization results in ectopic fat deposition in the liver which causes endoplasmic reticulum stress, mitochondrial dysfunction, and oxidative stress resulting in increased cytokine production and subsequent inflammation. Similarly, IR with hyperinsulinemia cause hyperandrogenism, the hallmark of PCOS, and inflammation in the ovaries. Proinflammatory cytokines from both liver and ovaries aggravate IR thus providing a complex interaction between adipose tissue, liver, and ovaries in inducing metabolic abnormalities in obese subjects. Although many pathogenic mechanisms of IR, NAFLD/MASLD, and PCOS are known, there is still no effective therapy for these entities suggesting the need for further evaluation of their pathogenesis. Extracellular vesicles (EVs) represent a novel cross-talk mechanism between organs and include membrane-bound vesicles containing proteins, lipids, and nucleic acids that may change the phenotype and function of target cells. Adipose tissue releases EVs that promote IR, the development of all stages of NAFLD/MASLD and PCOS, while mesenchymal stem cell-derived AVs may alleviate metabolic abnormalities and may represent a novel therapeutic device in NAFLD/MASLD, and PCOS. The purpose of this review is to summarize the current knowledge on the role of adipose tissue-derived EVs in the pathogenesis of IR, NAFLD/MASLD, and PCOS.

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.

OMIP-104: A 30-color spectral flow cytometry panel for comprehensive analysis of immune cell composition and macrophage subsets in mouse metabolic organs

Obesity-induced chronic low-grade inflammation, also known as metaflammation, results from alterations of the immune response in metabolic organs and contributes to the development of fatty liver diseases and type 2 diabetes. The diversity of tissue-resident leukocytes involved in these metabolic dysfunctions warrants an in-depth immunophenotyping in order to elucidate disease etiology. Here, we present a 30-color, full spectrum flow cytometry panel, designed to (i) identify the major innate and adaptive immune cell subsets in murine liver and white adipose tissues and (ii) discriminate various tissue-specific myeloid subsets known to contribute to the development of metabolic dysfunctions. This panel notably allows for distinguishing embryonically-derived liver-resident Kupffer cells from newly recruited monocyte-derived macrophages and KCs. Furthermore, several adipose tissue macrophage (ATM) subsets, including perivascular macrophages, lipid-associated macrophages, and pro-inflammatory CD11c+ ATMs, can also be identified. Finally, the panel includes cell-surface markers that have been associated with metabolic activation of different macrophage and dendritic cell subsets. Altogether, our spectral flow cytometry panel allows for an extensive immunophenotyping of murine metabolic tissues, with a particular focus on metabolically-relevant myeloid cell subsets, and can easily be adjusted to include various new markers if needed.

Sitagliptin Alleviates Obesity in Immature Mice by Inhibiting Oxidative Stress and Inflammation

To investigate the impact of Sitagliptin against obesity and the underlying mechanism. Obese immature mice were treated with 10, 30, and 90 mg/kg Sitagliptin, respectively. The body weights were recorded and the level of serum biochemical indexes were detected. The visceral fat ratio of each mouse was determined. The pathological change in adipose tissues was determined by HE staining, while F4/80 and CD206 levels in adipose tissues were determined by the immunohistochemical analysis. Lipid formation was evaluated by Oil red O staining assay. RAW264.7 cells were stimulated using oxLDL, followed by being incubated with different concentrations of Sitagliptin. The release of ADPN, IL-6, IL-1β, TNF-α, and the activity of SOD, was measured by ELISA assay. Western blotting was applied to determine adipsin, Nrf2, Keap1, and HO-1 protein levels. ROS level was checked using the DCFH-DA assay. RT-PCR assay was utilized to detect the mRNA levels of IL-6, IL-1β, TNF-α, Nrf2, Keap1, and HO-1. The body weight gain, infiltration of multinucleated cells, enlarged size of adipocytes, increased lipid accumulation, elevated visceral fat ratio, declined ADPN level, upregulated adipsin, and disordered serum biochemical indexes in obese immature mice were statistically significantly reversed by Sitagliptin. Excessive release of inflammatory factors and upregulated F4/80 and CD206 were observed in obese immature mice, which were statistically significantly repressed by Sitagliptin. Furthermore, the elevated MDA level, increased SOD activity, and inhibited Nrf2 pathway in obese immature mice were significantly reversed by Sitagliptin. In oxLDL stimulated RAW264.7 cells, increased release of inflammatory factors, ROS, and MDA, elevated SOD activity, and inactivated Nrf2 pathway were observed, which were statistically significantly abolished by the treatment of Sitagliptin. Sitagliptin alleviated obesity in immature mice by inhibiting inflammation and oxidative stress.

Potential impact of underlying diseases influencing ADME in nonclinical safety assessment

Nonclinical studies involve in vitro, in silico, and in vivo experiments to assess the toxicokinetics, toxicology, and safety pharmacology of drugs according to regulatory requirements by a national or international authority. In this review, we summarize the potential effects of various underlying diseases governing the absorption, distribution, metabolism, and excretion (ADME) of drugs to consider the use of animal models of diseases in nonclinical trials. Obesity models showed alterations in hepatic metabolizing enzymes, transporters, and renal pathophysiology, which increase the risk of drug-induced toxicity. Diabetes models displayed changes in hepatic metabolizing enzymes, transporters, and glomerular filtration rates (GFR), leading to variability in drug responses and susceptibility to toxicity. Animal models of advanced age exhibited impairment of drug metabolism and kidney function, thereby reducing the drug-metabolizing capacity and clearance. Along with changes in hepatic metabolic enzymes, animal models of metabolic syndrome-related hypertension showed renal dysfunction, resulting in a reduced GFR and urinary excretion of drugs. Taken together, underlying diseases can induce dysfunction of organs involved in the ADME of drugs, ultimately affecting toxicity. Therefore, the use of animal models of representative underlying diseases in nonclinical toxicity studies can be considered to improve the predictability of drug side effects before clinical trials.

The Effect of Retinol Acetate on Liver Fibrosis Depends on the Temporal Features of the Development of Pathology

Background

The effect of vitamin A on the manifestations of liver fibrosis is controversial and establishing the causes of its multidirectional influence is an urgent problem. In the work, the functional characteristics of the liver with Cu-induced fibrosis were determined after the restoration of vitamin A to the control level at the F0/F1 stage.

Methods

In animals with liver fibrosis, classical indicators of physiology, functional activity of the liver, histological, and hematological characteristics were determined; the content of calcium and ROS was determined in bone marrow cells.

Results

It was shown that in the liver with Cu-induced fibrosis, the restoration of vitamin A content to control values after per os injections of a retinol acetate solution at a dose of 0.10 mg (300 IU)/100 g of body weight in the early stages of this pathology development (Fо/F1) was accompanied by: a decrease in the number of immunocompetent cells in the bloodstream to control values; normalization of the amount of calcium ions and ROS in bone marrow cells; restoration to the control level of activity of alkaline phosphatase; an increase in the number of binuclear hepatocytes; and restoration of the dynamics of body weight growth in experimental animals, even against the background of the ongoing action of the hepatotoxic factor.

Conclusion

We came to the conclusion that the multidirectional action of vitamin A, which occurs in liver fibrosis, depends not only on the concentration of vitamin A in the liver but also on temporal characteristics of cellular and metabolic links involved in the adaptive response formation. It was suggested that knowledge of the initial temporal metabolic characteristics and the amount of vitamin A in the liver, taking into account the stages of fibrosis development, can be an effective way to restore the altered homeostatic parameters of the body.

Immunotherapy targeting the obese white adipose tissue microenvironment: Focus on non-communicable diseases

Obesity triggers inflammatory responses in the microenvironment of white adipose tissue, resulting in chronic systemic inflammation and the subsequent development of non-communicable diseases, including type 2 diabetes, coronary heart disease, and breast cancer. Current therapy approaches for obesity-induced non-communicable diseases persist in prioritizing symptom remission while frequently overlooking the criticality of targeting and alleviating inflammation at its source. Accordingly, this review highlights the importance of the microenvironment of obese white adipose tissue and the promising potential of employing immunotherapy to target it as an effective therapeutic approach for non-communicable diseases induced by obesity. Additionally, this review discusses the challenges and offers perspective about the immunotherapy targeting the microenvironment of obese white adipose tissue.

The molecular mechanism of macrophage-adipocyte crosstalk in maintaining energy homeostasis

Interactions between macrophages and adipocytes in adipose tissue are critical for the regulation of energy metabolism and obesity. Macrophage polarization induced by cold or other stimulations can drive metabolic reprogramming of adipocytes, browning, and thermogenesis. Accordingly, investigating the roles of macrophages and adipocytes in the maintenance of energy homeostasis is critical for the development of novel therapeutic approaches specifically targeting macrophages in metabolic disorders such as obesity. Current review outlines macrophage polarization not only regulates the release of central nervous system and inflammatory factors, but controls mitochondrial function, and other factor that induce metabolic reprogramming of adipocytes and maintain energy homeostasis. We also emphasized on how the adipocytes conversely motivate the polarization of macrophage. Exploring the interactions between adipocytes and macrophages may provide new therapeutic strategies for the management of obesity-related metabolic diseases.

Schistosoma mansoni infection induces hepatic metallothionein and S100 protein expression alongside metabolic dysfunction in hamsters

Schistosomiasis, a widespread neglected tropical disease, presents a complex and multifaceted clinical-pathological profile. Using hamsters as final hosts, we dissected molecular events following Schistosoma mansoni infection in the liver-the organ most severely affected in schistosomiasis patients. Employing tandem mass tag-based proteomics, we studied alterations in the liver proteins in response to various infection modes and genders. We examined livers from female and male hamsters that were: noninfected (control), infected with either unisexual S. mansoni cercariae (single-sex) or both sexes (bisex). The infection induced up-regulation of proteins associated with immune response, cytoskeletal reorganization, and apoptotic signaling. Notably, S. mansoni egg deposition led to the down-regulation of liver factors linked to energy supply and metabolic processes. Gender-specific responses were observed, with male hamsters showing higher susceptibility, supported by more differentially expressed proteins than found in females. Of note, metallothionein-2 and S100a6 proteins exhibited substantial up-regulation in livers of both genders, suggesting their pivotal roles in the liver's injury response. Immunohistochemistry and real-time-qPCR confirmed strong up-regulation of metallothionein-2 expression in the cytoplasm and nucleus upon the infection. Similar findings were seen for S100a6, which localized around granulomas and portal tracts. We also observed perturbations in metabolic pathways, including down-regulation of enzymes involved in xenobiotic biotransformation, cellular energy metabolism, and lipid modulation. Furthermore, lipidomic analyses through liquid chromatography-tandem mass spectrometry and matrix-assisted laser desorption/ionization mass spectrometry imaging identified extensive alterations, notably in cardiolipin and triacylglycerols, suggesting specific roles of lipids during pathogenesis. These findings provide unprecedented insights into the hepatic response to S. mansoni infection, shedding light on the complexity of liver pathology in this disease.

Population-enriched innate immune variants may identify candidate gene targets at the intersection of cancer and cardio-metabolic disease

Both cancer and cardio-metabolic disease disparities exist among specific populations in the US. For example, African Americans experience the highest rates of breast and prostate cancer mortality and the highest incidence of obesity. Native and Hispanic Americans experience the highest rates of liver cancer mortality. At the same time, Pacific Islanders have the highest death rate attributed to type 2 diabetes (T2D), and Asian Americans experience the highest incidence of non-alcoholic fatty liver disease (NAFLD) and cancers induced by infectious agents. Notably, the pathologic progression of both cancer and cardio-metabolic diseases involves innate immunity and mechanisms of inflammation. Innate immunity in individuals is established through genetic inheritance and external stimuli to respond to environmental threats and stresses such as pathogen exposure. Further, individual genomes contain characteristic genetic markers associated with one or more geographic ancestries (ethnic groups), including protective innate immune genetic programming optimized for survival in their corresponding ancestral environment(s). This perspective explores evidence related to our working hypothesis that genetic variations in innate immune genes, particularly those that are commonly found but unevenly distributed between populations, are associated with disparities between populations in both cancer and cardio-metabolic diseases. Identifying conventional and unconventional innate immune genes that fit this profile may provide critical insights into the underlying mechanisms that connect these two families of complex diseases and offer novel targets for precision-based treatment of cancer and/or cardio-metabolic disease.

Metabolites: a converging node of host and microbe to explain meta-organism

Meta-organisms encompassing the host and resident microbiota play a significant role in combatting diseases and responding to stress. Hence, there is growing traction to build a knowledge base about this ecosystem, particularly to characterize the bidirectional relationship between the host and microbiota. In this context, metabolomics has emerged as the major converging node of this entire ecosystem. Systematic comprehension of this resourceful omics component can elucidate the organism-specific response trajectory and the communication grid across the ecosystem embodying meta-organisms. Translating this knowledge into designing nutraceuticals and next-generation therapy are ongoing. Its major hindrance is a significant knowledge gap about the underlying mechanisms maintaining a delicate balance within this ecosystem. To bridge this knowledge gap, a holistic picture of the available information has been presented with a primary focus on the microbiota-metabolite relationship dynamics. The central theme of this article is the gut-brain axis and the participating microbial metabolites that impact cerebral functions.

Adipose tissue indices predict prognosis in hodgkin lymphoma

INTRODUCTION BACKGROUND

This study evaluated the impact of adipose tissue indices on prognosis of HL.

METHODS

Fifty-five patients with newly diagnosed Hodgkin Lymphoma were evaluated retrospectively for association with adipose tissue indices (total abdominal tissue volume, radiodensity, subcutaneous and visceral adipose tissue SUVmax value and prognostic factors for Hodgkin Lymphoma such as IPS-3, IPS-7, stage, sedimentation, progression free and overall survival.

RESULTS

For IPS-3, SAT SUVmax and TAAT radiodensity were significantly increased in high-risk patients (2and 3) compared to group 0 and 1. For IPS-7, total abdominal adipose volume was significantly decreased in high-risk patients, SAT SUVmax significantly increased in high-risk patients and decreased in low-risk patients. In addition, SAT SUVmax was significantly increased in patients with high sedimentation rate, with B symptoms and who passed away during follow-up. SAT SUVmax showed moderate positive correlation with sedimentation, IPS-3, IPS-7, and stage. In addition, it was observed that TAAT radiodensity and SAT SUVmax were significantly better for determining prognosis than other adipose tissue indices. Roc analysis showed that the diagnostic value of all adipose tissue indices in predicting IPS-3 and IPS-7 prognoses were statistically significant.

CONCLUSION

SAT SUVmax and TAAT radiodensity were two new and independent markers with diagnostic value in predicting prognosis.

Orchestration of the Adipose Tissue Immune Landscape by Adipocytes

Obesity is epidemic and of great concern because of its comorbid and costly inflammatory-driven complications. Extensive investigations in mice have elucidated highly coordinated, well-balanced interactions between adipocytes and immune cells in adipose tissue that maintain normal systemic metabolism in the lean state, while in obesity, proinflammatory changes occur in nearly all adipose tissue immune cells. Many of these changes are instigated by adipocytes. However, less is known about obesity-induced adipose-tissue immune cell alterations in humans. Upon high-fat diet feeding, the adipocyte changes its well-known function as a metabolic cell to assume the role of an immune cell, orchestrating proinflammatory changes that escalate inflammation and progress during obesity. This transformation is particularly prominent in humans. In this review, we (a) highlight a leading and early role for adipocytes in promulgating inflammation, (b) discuss immune cell changes and the time course of these changes (comparing humans and mice when possible), and (c) note how reversing proinflammatory changes in most types of immune cells, including adipocytes, rescues adipose tissue from inflammation and obese mice from insulin resistance.

Glucocorticoids increase adiposity by stimulating Krüppel-like factor 9 expression in macrophages

The mechanisms underlying glucocorticoid (GC)-induced obesity are poorly understood. Macrophages are the primary targets by which GCs exert pharmacological effects and perform critical functions in adipose tissue homeostasis. Here, we show that macrophages are essential for GC-induced obesity. Dexamethasone (Dex) strongly induced Krüppel-like factor 9 (Klf9) expression in macrophages. Similar to Dex, lentivirus-mediated Klf9 overexpression inhibits M1 and M2a markers expression, causing macrophage deactivation. Furthermore, the myeloid-specific Klf9 transgene promotes obesity. Conversely, myeloid-specific Klf9-knockout (mKlf9KO) mice are lean. Moreover, myeloid Klf9 knockout largely blocks obesity induced by chronic GC treatment. Mechanistically, GC-inducible KLF9 recruits the SIN3A/HDAC complex to the promoter regions of Il6, Ptgs2, Il10, Arg1, and Chil3 to inhibit their expression, subsequently reducing thermogenesis and increasing lipid accumulation by inhibiting STAT3 signaling in adipocytes. Thus, KLF9 in macrophages integrates the beneficial anti-inflammatory and adverse metabolic effects of GCs and represents a potential target for therapeutic interventions.

Adipose tissue inflammation linked to obesity: A review of current understanding, therapies and relevance of phyto-therapeutics

Obesity is a current global challenge affecting all ages and is characterized by the up-regulated secretion of bioactive factors/pathways which result in adipose tissue inflammation (ATI). Current obesity therapies are mainly focused on lifestyle (diet/nutrition) changes. This is because many chemosynthetic anti-obesogenic medications cause adverse effects like diarrhoea, dyspepsia, and faecal incontinence, among others. As such, it is necessary to appraise the efficacies and mechanisms of action of safer, natural alternatives like plant-sourced compounds, extracts [extractable phenol (EP) and macromolecular antioxidant (MA) extracts], and anti-inflammatory peptides, among others, with a view to providing a unique approach to obesity care. These natural alternatives may constitute potent therapies for ATI linked to obesity. The potential of MA compounds (analysed for the first time in this review) and extracts in ATI and obesity management is elucidated upon, while also highlighting research gaps and future prospects. Furthermore, immune cells, signalling pathways, genes, and adipocyte cytokines play key roles in ATI responses and are targeted in certain therapies. As a result, this review gives an in-depth appraisal of ATI linked to obesity, its causes, mechanisms, and effects of past, present, and future therapies for reversal and alleviation of ATI. Achieving a significant decrease in morbidity and mortality rates attributed to ATI linked to obesity and related comorbidities is possible as research improves our understanding over time.

Immunomodulatory leptin receptor+ sympathetic perineurial barrier cells protect against obesity by facilitating brown adipose tissue thermogenesis

Adipose tissues (ATs) are innervated by sympathetic nerves, which drive reduction of fat mass via lipolysis and thermogenesis. Here, we report a population of immunomodulatory leptin receptor-positive (LepR+) sympathetic perineurial barrier cells (SPCs) present in mice and humans, which uniquely co-express Lepr and interleukin-33 (Il33) and ensheath AT sympathetic axon bundles. Brown ATs (BATs) of mice lacking IL-33 in SPCs (SPCΔIl33) had fewer regulatory T (Treg) cells and eosinophils, resulting in increased BAT inflammation. SPCΔIl33 mice were more susceptible to diet-induced obesity, independently of food intake. Furthermore, SPCΔIl33 mice had impaired adaptive thermogenesis and were unresponsive to leptin-induced rescue of metabolic adaptation. We therefore identify LepR+ SPCs as a source of IL-33, which orchestrate an anti-inflammatory BAT environment, preserving sympathetic-mediated thermogenesis and body weight homeostasis. LepR+IL-33+ SPCs provide a cellular link between leptin and immune regulation of body weight, unifying neuroendocrinology and immunometabolism as previously disconnected fields of obesity research.

Gut microbiota-mediated polyphenol metabolism is restrained by parasitic whipworm infection and associated with altered immune function in mice

Polyphenols are phytochemicals commonly found in plant-based diets which have demonstrated immunomodulatory and anti-inflammatory properties. However, the interplay between polyphenols and pathogens at mucosal barrier surfaces has not yet been elucidated in detail. Here, we show that proanthocyanidin (PAC) polyphenols interact with gut parasites to influence immune function and gut microbial-derived metabolites in mice. PAC intake inhibited mastocytosis during infection with the small intestinal roundworm Heligmosomoides polygyrus, and altered the host tissue transcriptome at the site of infection with the large intestinal whipworm Trichuris muris, with a notable enhancement of type-1 inflammatory and interferon-driven gene pathways. In the absence of infection, PAC intake promoted the expansion of Turicibacter within the gut microbiota, increased fecal short chain fatty acids, and enriched phenolic metabolites such as phenyl-γ-valerolactones in the cecum. However, these putatively beneficial effects were reduced in PAC-fed mice infected with T. muris, suggesting concomitant parasite infection can attenuate gut microbial-mediated PAC catabolism. Collectively, our results suggest an inter-relationship between a phytonutrient and infection, whereby PAC may augment parasite-induced inflammation (most prominently with the cecum dwelling T. muris), and infection may abrogate the beneficial effects of health-promoting phytochemicals.

Adolescent and young adult Hodgkin lymphoma patients at risk for subcutaneous fat gain during early cancer treatment: a brief report

Computed tomography scans were assessed for subcutaneous fat area and density at thoracic vertebra 4 in 65 adolescent and young adult (AYA) patients with Hodgkin lymphoma. Subcutaneous fat was quantified over 3 timepoints; (1) baseline, (2) end of initial anthracycline treatment (EOT) and (3) 1 year. Fat area increased at EOT (62.3 ± 5.4 cm/m2 vs 53.5 ± 5.0 cm/m2, p < 0.01) and 1 year (65.8 ± 5.6 cm/m2 vs 53.5 ± 5.0 cm/m2, p < 0.01) compared to baseline. Fat density significantly decreased at EOT (-91.2 ± 1.4 HU vs -86.5 ± 1.4 HU, p < 0.01) and at 1 year (-90.3 ± 1.6 HU vs -86.5 ± 1.4 HU, p = 0.01) compared to baseline. Female, radiation receiving, and anthracycline dosage >250mg/m2subgroups experienced significant fat gain (p < 0.05 for all). Female AYA Hodgkin lymphoma patients receiving radiation, and/or high-dose anthracyclines may be at higher risk of subcutaneous fat gain during therapy.

Postprandial Dysmetabolism and Its Medical Implications

An unbalanced diet increases the risk of developing a variety of chronic diseases and cancers, leading to higher morbidity and mortality rates worldwide. Low-grade systemic chronic inflammation mediated by the activation of the innate immune system is common to all these pathologies. Inflammation is a biological response of the body and a normal part of host defense to combat the effects of bacteria, viruses, toxins and macronutrients. However, when the innate immune system is constantly activated, it can promote the development of low-grade systemic chronic inflammation, which could play an important role in the development of chronic diseases and cancer. Since most chronic inflammatory diseases are associated with diet, a balanced healthy diet high in anti-inflammatory food components could prevent chronic diseases and cancer. The cells of the body's immune system produce chemokines and cytokines which can have pro-inflammatory and tumor-promoting as well as anti-inflammatory and tumor-fighting functions. A challenge in the future will be to assess whether polymorphisms in immune-related genes may play a role in promoting pro-inflammatory activity. Thanks to this duality, future research on immune regulation could focus on how innate immune cells can be modified to convert a pro-inflammatory and tumor-friendly microenvironment into an anti-inflammatory and anti-tumor one. This review describes inflammatory responses mediated by the innate immune system in various diseases such as hyperglycemia and/or hyperlipemia, obesity, type II diabetes, cardiovascular disease and cancer.

Transcriptomics profiling reveal the heterogeneity of white and brown adipocyte

The marker genes associated with white adipocytes and brown adipocytes have been previously identified; however, these markers have not been updated in several years, and the differentiation process of preadipocytes remains relatively fixed. Consequently, there has been a lack of exploration into alternative differentiation schemes. In this particular study, we present a transcriptional signature specific to brown adipocytes and white adipocytes. Notably, our findings reveal that ZNF497, ZIC1, ZFY, UTY, USP9Y, TXLNGY, TTTY14, TNNT3, TNNT2, TNNT1, TNNI1, TNNC1, TDRD15, SOX11, SLN, SFRP2, PRKY, PAX3KLHL40, PAX3, INKA2-AS1, SOX11, and TDRD15 exhibit high expression levels in brown adipocytes. XIST, HOXA10, PCAT19, HOXA7, PLSCR3, and AVPR1A exhibited high expression levels in white adipocytes, suggesting their potential as novel marker genes for the transition from white to brown adipocytes. Furthermore, our analysis revealed the coordinated activation of several pathways, including the PPAR signaling pathway, focal adhesion, retrograde endocannabinoid signaling, oxidative phosphorylation, PI3K-Akt signaling pathway, and thermogenesis pathways, in brown adipocytes. Moreover, in contrast to prevailing culture techniques, we conducted a comparative analysis of the differentiation protocols for white preadipocytes and brown preadipocytes, revealing that the differentiation outcome remained unaffected by the diverse culture schemes employed. However, the expression levels of certain marker genes in both adipocyte types were found to be altered. This investigation not only identified potential novel marker genes for adipocytes but also examined the impact of different differentiation methods on preadipocyte maturation. Consequently, these findings offer significant insights for further research on the differentiation processes of diverse adipocyte subtypes.

Lifestyle and host determinants of antitumor immunity and cancer health disparities

Lifestyle factors exert profound effects on host physiology and immunology. Disparities in cancer outcomes persist as a complex and multifaceted challenge, necessitating a comprehensive understanding of the interplay between host environment and antitumor immune responses. Determinants of health - such as obesity, diet, exercise, stress, or sleep disruption - have the potential for modification, yet some exert long-lasting effects and may challenge the notion of complete reversibility. Herein we review intersectional considerations of lifestyle immunity and the impact on tumor immunology and disparities in cancer outcomes, with a focus on obesity.

Oral Immunotherapy Reshapes Intestinal Immunosuppression via Metabolic Reprogramming to Enhance Systemic Anti-Tumor Immunity

Tumor immunotherapy offers a new paradigm to treat cancer; however, the existing regimens are accompanied by the dilemma of insufficient therapeutic outcomes and off-target adverse effects. The intestinal immune system contains a bulk of immune cells, which can be important contributors to the maintenance of systemic immune homeostasis. However, manipulating intestinal immunity to achieve systemic anti-tumor immunity is extremely challenging. Here, an oral immunotherapy strategy is reported using immune-enhancing fullerenes (IEF) that can reinvigorate anti-tumor immunity via immune cell-metabolic reprogramming of intestinal immune cells. Findings show that IEF can remodel anti-inflammatory macrophages into tumor-killing macrophages by regulating the energy metabolism pathway from oxidative phosphorylation (OXPHOS) to glycolysis. Consequently, IEF can reprogram the immunosuppressive intestinal immunity and enhance sys temic immunity in vivo, thereby boosting anti-tumor immunity and converting "cold" tumors into "hot" tumors. Oral immunotherapy strategy, modulating autoimmune cells in the intestine and achieving systemic anti-tumor immunity, can ensure safe and efficient tumor immunotherapy.

Dose Intervals and Time since Final Dose on Changes in Metabolic Indices after COVID-19 Vaccination

The rapid development and implementation of COVID-19 vaccines merit understanding its effects on metabolic indices. This retrospective longitudinal study investigated the influence of first-to-second-dose intervals and time since the final dose on the metabolic indices of individuals receiving COVID-19 vaccinations. A total of 318 Saudi subjects (59.7% females) aged 12-60 years received COVID-19 vaccines via the national vaccination program. We collected the anthropometric data and fasting blood samples at specific time points before vaccination and after the final vaccination dose, and biochemical metabolic indices, including glucose and lipid profile, were measured. We also collected the dates of vaccination and COVID-19 history during the study period. The participants were stratified into groups based on first-to-second-dose intervals and time since the final dose to compare pre-and post-vaccination changes in metabolic indices between the groups. Logistic regression analysis revealed no differences in pre- to post-vaccination metabolic status between groups based on first-to-second-dose intervals in either adolescents or adults. However, shorter intervals (≤6 months) between the final dose and follow-up were associated with a decrease in total cardiometabolic components, especially triglyceride levels (OR = 0.39, 95% CI: (0.22-0.68), p < 0.001) than longer intervals (>6 months) in adults. In conclusion, time duration since final dose was associated with pre- to post-vaccination changes in metabolic indices, especially triglyceride levels, indicating that post-vaccination improvements wane over time. Further research is needed to validate the observed relationship, as it may contribute to optimizing vaccine effectiveness and safety in the future.

Immunometabolism of dendritic cells in health and disease

Dendritic cells (DCs) are crucial mediators that bridge the innate and adaptive immune responses. Cellular rewiring of metabolism is an emerging regulator of the activation, migration, and functional specialization of DC subsets in specific microenvironments and immunological conditions. DCs undergo metabolic adaptation to exert immunogenic or tolerogenic effects in different contexts. Also, beyond their intracellular metabolic and signaling roles, metabolites and nutrients mediate the intercellular crosstalk between DCs and other cell types, and such crosstalk orchestrates DC function and immune responses. Here, we provide a comprehensive review of the metabolic regulation of DC biology in various contexts and summarize the current understanding of such regulation in directing immune homeostasis and inflammation, specifically with respect to infections, autoimmunity, tolerance, cancer, metabolic diseases, and crosstalk with gut microbes. Understanding context-specific metabolic alterations in DCs may identify mechanisms for physiological and pathological functions of DCs and yield potential opportunities for therapeutic targeting of DC metabolism in many diseases.

STE20 kinase TAOK3 regulates type 2 immunity and metabolism in obesity

Healthy adipose tissue (AT) contains ST2+ Tregs, ILC2s, and alternatively activated macrophages that are lost in mice or humans on high caloric diet. Understanding how this form of type 2 immunity is regulated could improve treatment of obesity. The STE20 kinase Thousand And One amino acid Kinase-3 (TAOK3) has been linked to obesity in mice and humans, but its precise function is unknown. We found that ST2+ Tregs are upregulated in visceral epididymal white AT (eWAT) of Taok3-/- mice, dependent on IL-33 and the kinase activity of TAOK3. Upon high fat diet feeding, metabolic dysfunction was attenuated in Taok3-/- mice. ST2+ Tregs disappeared from eWAT in obese wild-type mice, but this was not the case in Taok3-/- mice. Mechanistically, AT Taok3-/- Tregs were intrinsically more responsive to IL-33, through higher expression of ST2, and expressed more PPARγ and type 2 cytokines. Thus, TAOK3 inhibits adipose tissue Tregs and regulates immunometabolism under excessive caloric intake.

Obesity alters monocyte developmental trajectories to enhance metastasis

Obesity is characterized by chronic systemic inflammation and enhances cancer metastasis and mortality. Obesity promotes breast cancer metastasis to lung in a neutrophil-dependent manner; however, the upstream regulatory mechanisms of this process remain unknown. Here, we show that obesity-induced monocytes underlie neutrophil activation and breast cancer lung metastasis. Using mass cytometry, obesity favors the expansion of myeloid lineages while restricting lymphoid cells within the peripheral blood. RNA sequencing and flow cytometry revealed that obesity-associated monocytes resemble professional antigen-presenting cells due to a shift in their development and exhibit enhanced MHCII expression and CXCL2 production. Monocyte induction of the CXCL2-CXCR2 axis underlies neutrophil activation and release of neutrophil extracellular traps to promote metastasis, and enhancement of this signaling axis is observed in lung metastases from obese cancer patients. Our findings provide mechanistic insight into the relationship between obesity and cancer by broadening our understanding of the interactive role that myeloid cells play in this process.

Natural deletion of mouse carboxylesterases Ces1c/d/e impacts drug metabolism and metabolic syndrome development

Mammalian carboxylesterase 1 enzymes can hydrolyze many xenobiotic chemicals and endogenous lipids. We here identified and characterized a mouse strain (FVB/NKI) in which three of the eight Ces1 genes were spontaneously deleted, removing Ces1c and Ces1e partly, and Ces1d entirely. We studied the impact of this Ces1c/d/e deficiency on drug and lipid metabolism and homeostasis. Ces1c/d/e-/- mice showed strongly impaired conversion of the anticancer prodrug irinotecan to its active metabolite SN-38 in plasma, spleen and lung. Plasma hydrolysis of the oral anticancer prodrug capecitabine to 5-DFCR was also profoundly reduced in Ces1c/d/e-/- mice. Our findings resolved previously unexplained FVB/NKI pharmacokinetic anomalies. On a medium-fat diet, Ces1c/d/e-/- female mice exhibited moderately higher body weight, mild inflammation in gonadal white adipose tissue (gWAT), and increased lipid load in brown adipose tissue (BAT). Ces1c/d/e-/- males showed more pronounced inflammation in gWAT and an increased lipid load in BAT. On a 5-week high-fat diet exposure, Ces1c/d/e deficiency predisposed to developing obesity, enlarged and fatty liver, glucose intolerance and insulin resistance, with severe inflammation in gWAT and increased lipid load in BAT. Hepatic proteomics analysis revealed that the acute phase response, involved in the dynamic cycle of immunometabolism, was activated in these Ces1c/d/e-/- mice. This may contribute to the obesity-related chronic inflammation and adverse metabolic disease in this strain. While Ces1c/d/e deficiency clearly exacerbated metabolic syndrome development, long-term (18-week) high-fat diet exposure overwhelmed many, albeit not all, observed phenotypic differences.

Effects of gut microbiota on omega-3-mediated ovary and metabolic benefits in polycystic ovary syndrome mice

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disorder that frequently exhibits low-grade inflammation, pro-oxidant activity, and gut dysbiosis. PCOS has become one of the leading causes of female infertility worldwide. Recently, omega-3 polyunsaturated fatty acids (PUFAs) have been proven to benefit metabolic disorders in PCOS patients. However, its roles in the regulation of metabolic and endocrinal balances in PCOS pathophysiology are not clear. In the present study, we aimed to explore how omega-3 PUFAs alleviate ovarian dysfunction and insulin resistance in mice with dehydroepiandrosterone (DHEA)-induced PCOS by modulating the gut microbiota.

METHODS

We induced PCOS in female mice by injecting them with DHEA and then treated them with omega-3 PUFAs. 16S ribosomal DNA (rDNA) amplicon sequencing, fecal microbiota transplantation (FMT) and antibiotic treatment were used to evaluate the role of microbiota in the regulation of ovarian functions and insulin resistance (IR) by omega-3 PUFAs. To further investigate the mechanism of gut microbiota on omega-3-mediated ovarian and metabolic protective effects, inflammatory and oxidative stress markers in ovaries and thermogenic markers in subcutaneous and brown adipose tissues were investigated.

RESULTS

We found that oral supplementation with omega-3 PUFAs ameliorates the PCOS phenotype. 16S rDNA analysis revealed that omega-3 PUFA treatment increased the abundance of beneficial bacteria in the gut, thereby alleviating DHEA-induced gut dysbiosis. Antibiotic treatment and FMT experiments further demonstrated that the mechanisms underlying omega-3 benefits likely involve direct effects on the ovary to inhibit inflammatory cytokines such as IL-1β, TNF-α and IL-18. In addition, the gut microbiota played a key role in the improvement of adipose tissue morphology and function by decreasing multilocular cells and thermogenic markers such as Ucp1, Pgc1a, Cited and Cox8b within the subcutaneous adipose tissues.

CONCLUSION

These findings indicate that omega-3 PUFAs ameliorate androgen-induced gut microbiota dysbiosis. The gut microbiota plays a key role in the regulation of omega-3-mediated IR protective effects in polycystic ovary syndrome mice. Moreover, omega-3 PUFA-regulated improvements in the ovarian dysfunction associated with PCOS likely involve direct effects on the ovary to inhibit inflammation. Our findings suggest that omega-3 supplementation may be a promising therapeutic approach for the treatment of PCOS by modulating gut microbiota and alleviating ovarian dysfunction and insulin resistance.

Dietary non-starch polysaccharides impair immunity to enteric nematode infection

BACKGROUND

The influence of diet on immune function and resistance to enteric infection and disease is becoming ever more established. Highly processed, refined diets can lead to inflammation and gut microbiome dysbiosis, whilst health-promoting dietary components such as phytonutrients and fermentable fibres are thought to promote a healthy microbiome and balanced mucosal immunity. Chicory (Cichorium intybus) is a leafy green vegetable rich in fibres and bioactive compounds that may promote gut health.

RESULTS

Unexpectedly, we here show that incorporation of chicory into semisynthetic AIN93G diets renders mice susceptible to infection with enteric helminths. Mice fed a high level of chicory leaves (10% dry matter) had a more diverse gut microbiota, but a diminished type-2 immune response to infection with the intestinal roundworm Heligmosomoides polygyrus. Furthermore, the chicory-supplemented diet significantly increased burdens of the caecum-dwelling whipworm Trichuris muris, concomitant with a highly skewed type-1 immune environment in caecal tissue. The chicory-supplemented diet was rich in non-starch polysaccharides, particularly uronic acids (the monomeric constituents of pectin). In accordance, mice fed pectin-supplemented AIN93G diets had higher T. muris burdens and reduced IgE production and expression of genes involved in type-2 immunity. Importantly, treatment of pectin-fed mice with exogenous IL-25 restored type-2 responses and was sufficient to allow T. muris expulsion.

CONCLUSIONS

Collectively, our data suggest that increasing levels of fermentable, non-starch polysaccharides in refined diets compromises immunity to helminth infection in mice. This diet-infection interaction may inform new strategies for manipulating the gut environment to promote resistance to enteric parasites.

Senescent immune cells accumulation promotes brown adipose tissue dysfunction during aging

Brown adipose tissue (BAT)-mediated thermogenesis declines with age. However, the underlying mechanism remains unclear. Here we reveal that bone marrow-derived pro-inflammatory and senescent S100A8⁺ immune cells, mainly T cells and neutrophils, invade the BAT of male rats and mice during aging. These S100A8⁺ immune cells, coupled with adipocytes and sympathetic nerves, compromise axonal networks. Mechanistically, these senescent immune cells secrete abundant S100A8 to inhibit adipose RNA-binding motif protein 3 expression. This downregulation results in the dysregulation of axon guidance-related genes, leading to impaired sympathetic innervation and thermogenic function. Xenotransplantation experiments show that human S100A8⁺ immune cells infiltrate mice BAT and are sufficient to induce aging-like BAT dysfunction. Notably, treatment with S100A8 inhibitor paquinimod rejuvenates BAT axon networks and thermogenic function in aged male mice. Our study suggests that targeting the bone marrow-derived senescent immune cells presents an avenue to improve BAT aging and related metabolic disorders.

Obesity, Preserved Ejection Fraction Heart Failure, and Left Ventricular Remodeling

Owing to the overwhelming obesity epidemic, preserved ejection fraction heart failure commonly ensues in patients with severe obesity and the obese phenotype of preserved ejection fraction heart failure is now commonplace in clinical practice. Severe obesity and preserved ejection fraction heart failure share congruent cardiovascular, immune, and renal derangements that make it difficult to ascertain whether the obese phenotype of preserved ejection fraction heart failure is the convergence of two highly prevalent conditions or severe obesity enables the development and progression of the syndrome of preserved ejection fraction heart failure. Nevertheless, the obese phenotype of preserved ejection fraction heart failure provides a unique opportunity to assess whether sustained and sizeable loss of excess body weight via metabolic bariatric surgery reverses the concentric left ventricular remodeling that patients with preserved ejection fraction heart failure commonly display.

Modeling the innate inflammatory cGAS/STING pathway: sexually dimorphic effects on microglia and cognition in obesity and prediabetes

Introduction

The prevalence of obesity, prediabetes, and diabetes continues to grow worldwide. These metabolic dysfunctions predispose individuals to neurodegenerative diseases and cognitive impairment, including dementias such as Alzheimer's disease and Alzheimer's disease related dementias (AD/ADRD). The innate inflammatory cGAS/STING pathway plays a pivotal role in metabolic dysfunction and is an emerging target of interest in multiple neurodegenerative diseases, including AD/ADRD. Therefore, our goal was to establish a murine model to specifically target the cGAS/STING pathway to study obesity- and prediabetes-induced cognitive impairment.

Methods

We performed two pilot studies in cGAS knockout (cGAS-/-) male and female mice designed to characterize basic metabolic and inflammatory phenotypes and examine the impact of high-fat diet (HFD) on metabolic, inflammatory, and cognitive parameters.

Results

cGAS-/- mice displayed normal metabolic profiles and retained the ability to respond to inflammatory stimuli, as indicated by an increase in plasma inflammatory cytokine production in response to lipopolysaccharide injection. HFD feeding caused expected increases in body weight and decreases in glucose tolerance, although onset was accelerated in females versus males. While HFD did not increase plasma or hippocampal inflammatory cytokine production, it did alter microglial morphology to a state indicative of activation, particularly in female cGAS-/- mice. However, HFD negatively impacted cognitive outcomes in male, but not female animals.

Discussion

Collectively, these results suggest that cGAS-/- mice display sexually dimorphic responses to HFD, possibly based on differences in microglial morphology and cognition.

Mechanisms of obesity- and diabetes mellitus-related pancreatic carcinogenesis: a comprehensive and systematic review

Research on obesity- and diabetes mellitus (DM)-related carcinogenesis has expanded exponentially since these two diseases were recognized as important risk factors for cancers. The growing interest in this area is prominently actuated by the increasing obesity and DM prevalence, which is partially responsible for the slight but constant increase in pancreatic cancer (PC) occurrence. PC is a highly lethal malignancy characterized by its insidious symptoms, delayed diagnosis, and devastating prognosis. The intricate process of obesity and DM promoting pancreatic carcinogenesis involves their local impact on the pancreas and concurrent whole-body systemic changes that are suitable for cancer initiation. The main mechanisms involved in this process include the excessive accumulation of various nutrients and metabolites promoting carcinogenesis directly while also aggravating mutagenic and carcinogenic metabolic disorders by affecting multiple pathways. Detrimental alterations in gastrointestinal and sex hormone levels and microbiome dysfunction further compromise immunometabolic regulation and contribute to the establishment of an immunosuppressive tumor microenvironment (TME) for carcinogenesis, which can be exacerbated by several crucial pathophysiological processes and TME components, such as autophagy, endoplasmic reticulum stress, oxidative stress, epithelial-mesenchymal transition, and exosome secretion. This review provides a comprehensive and critical analysis of the immunometabolic mechanisms of obesity- and DM-related pancreatic carcinogenesis and dissects how metabolic disorders impair anticancer immunity and influence pathophysiological processes to favor cancer initiation.

HnRNPA2B1 Aggravates Inflammation by Promoting M1 Macrophage Polarization

Macrophages have critical contributions to both acute and chronic inflammatory diseases, for example, bowel disease and obesity, respectively. However, little is known about the post-transcriptional regulatory mechanisms in macrophage-mediated inflammatory diseases. hnRNPA2B1 (A2B1) is an RNA binding protein for mRNA fate determination. We showed that hnRNPA2B1 mRNA levels were increased in colon in dextran sodium sulfate (DSS)-induced colitis mice and in epididymal white adipose tissue (eWAT) and spleen of high-fat-diet (HFD)-induced obese mice. Consistently, mice with haploinsufficiency of A2B1 (A2B1 HET) are protected against DSS-induced acute colitis and HFD-induced obesity, with decreased M1 macrophages polarization in colon, eWAT and spleen. Mechanistically, A2B1 mRNA and protein levels were increased in LPS-stimulated RAW 264.7 macrophages, and A2B1 enhanced RNA stability of pro-inflammatory genes Tnfα, Il-6 and Il-1β for the regulation of macrophages polarization. Interestingly, A2B1 HET mice exhibited reduced white fat expansion, which was influenced by macrophages, since conditioned medium from macrophages with A2B1 manipulation significantly changed preadipocyte proliferation. Our data demonstrate that A2B1 plays a vital role in macrophage-mediated inflammation via regulating mRNA stability, suggesting that A2B1 may be served as a promising target for the intervention of acute and chronic inflammatory diseases.

Profiling of hepatic transcriptomes reveals modulatory effects of parasitic infection on the metabolic response to dietary polyphenols in pigs

Polyphenols are a class of bioactive plant compounds with health-promoting properties, however the interactions between polyphenols and pathogen infection and their cumulative impact on inflammation and metabolic health are not well understood. Here, we investigated if a sub-clinical parasitic infection modulates the hepatic response to dietary polyphenol supplementation in a porcine model. Pigs were fed a diet with or without 1% grape proanthocyanidin (PAC) for 28 days. During the final 14 days of the experiment, half the pigs in each dietary group were inoculated with the parasitic nematode Ascaris suum. Serum biochemistry was measured and hepatic transcriptional responses were determined by RNA-sequencing coupled with gene-set enrichment analysis. A. suum infection resulted in reduced serum phosphate, potassium and calcium, and increased serum iron concentrations. In uninfected pigs, PAC supplementation markedly changed the liver transcriptome including genes related to carbohydrate and lipid metabolism, insulin signaling, and bile acid synthesis. However, during A. suum infection, a separate set of genes were modulated by dietary PAC, indicating that the polyphenol-mediated effects were dependent on infection status. A. suum infection strongly influenced the expression of genes related to cellular metabolism, and, in contrast to the effects of PAC, these changes were mostly identical in both control-fed and PAC-fed pigs. Thus, the hepatic response to infection was mostly unaffected by concurrent polyphenol intake. We conclude that the presence of a commonly occurring parasite substantially influences the outcome of dietary polyphenol supplementation, which may have important relevance for nutritional interventions in populations where intestinal parasitism is widespread.

Inflammation of Mesenteric Adipose Tissue Correlates with Intestinal Injury and Disease Severity in Rats with Severe Acute Pancreatitis

BACKGROUND

Visceral adipose tissue (VAT) is related to SAP prognosis. As a depot of VAT, mesenteric adipose tissue (MAT) resides between pancreas and gut, which might affect SAP and the secondary intestinal injury.

AIMS

To investigate the changes of MAT in SAP.

METHODS

24 SD rats were randomly divided into four groups. 18 rats in SAP group were euthanized in time gradients (6 h, 24 h, and 48 h after modeling) and the others in control group. Blood samples and tissues of pancreas, gut, and MAT were taken for analysis.

RESULTS

Compared to the control group, SAP rats appeared MAT inflammation, presenting higher mRNA expression of TNF-α and IL-6 and lower IL-10, and histological changes after 6 h of modeling, which became worse over time. Flow cytometry showed that B lymphocytes increased in MAT after 24 h of SAP modeling and lasted up to 48 h, earlier than the changes of T lymphocytes and macrophages. The intestinal barrier integrity was damaged after 6 h of modeling, presenting lower mRNA and protein expression of ZO-1 and occludin, higher serum levels of LPS and DAO, with pathological changes, which gradually aggravated after 24 h and 48 h. SAP rats had higher serum levels of inflammatory indicators and revealed histological inflammation of pancreas, the severity of which increased with the passage of modeling time.

CONCLUSION

MAT appeared inflammation in early-stage SAP, and became worse over time, with the same trend as the intestinal barrier injury and the severity of pancreatitis. B lymphocytes infiltrated early in MAT, which might promote the MAT inflammation.

Imaging Guided Endogenic H2 -Augmented Electrochemo-Sonodynamic Domino Co-therapy of Tumor in Vivo

Precise and on-demand release of sufficient hydrogen (H₂ ) to tumor sites remains a key challenge for emerging H₂ -oncotherapy, and little is known about the physiological effects of "abundant" H₂ on complex tumor microenvironments (TME). Here, a highly efficient and cost-effective imaging-guided/-assessed H₂ -therapy of tumors based on a joint electrochemo-sonodynamic treatment (H₂ -EC/SD co-therapy) with strong "domino effect" triggered by endogenous H₂ generation at tumor sites is reported to speedily eliminate tumor tissue (≤80 mm³ ) within 1 day. Adequate H₂ is controllably generated in tumor sites through mild electrochemistry in vivo due to acidic TME by using clinical acupuncture Fe needles as electrodes. Besides starvation damage due to gas blockage/destruction of vessels, nano-/micro-bubbles of H₂ formed in situ can elevate the tumor's internal temperature and burst vessels to further destroy the tumor under ultrasound irradiation. Remarkably, vulnerable homeostasis of TME is disturbed as H₂ also participates in the physiological activity of tumor cells, leading to tumor dysfunction. Last but not least, the body's inflammatory response to cancer is reduced after the treatment, which is beneficial for the body's immune system during post-treatment recovery. Based on all of these merits, the H₂ -EC/SD co-therapy provides a potentially safe and viable therapeutic strategy for future clinical applications.

Carboxylesterase 1 family knockout alters drug disposition and lipid metabolism

The mammalian carboxylesterase 1 (Ces1/CES1) family comprises several enzymes that hydrolyze many xenobiotic chemicals and endogenous lipids. To investigate the pharmacological and physiological roles of Ces1/CES1, we generated Ces1 cluster knockout (Ces1 ^-/- ) mice, and a hepatic human CES1 transgenic model in the Ces1 ^-/- background (TgCES1). Ces1 ^-/- mice displayed profoundly decreased conversion of the anticancer prodrug irinotecan to SN-38 in plasma and tissues. TgCES1 mice exhibited enhanced metabolism of irinotecan to SN-38 in liver and kidney. Ces1 and hCES1 activity increased irinotecan toxicity, likely by enhancing the formation of pharmacodynamically active SN-38. Ces1 ^-/- mice also showed markedly increased capecitabine plasma exposure, which was moderately decreased in TgCES1 mice. Ces1 ^-/- mice were overweight with increased adipose tissue, white adipose tissue inflammation (in males), a higher lipid load in brown adipose tissue, and impaired blood glucose tolerance (in males). These phenotypes were mostly reversed in TgCES1 mice. TgCES1 mice displayed increased triglyceride secretion from liver to plasma, together with higher triglyceride levels in the male liver. These results indicate that the carboxylesterase 1 family plays essential roles in drug and lipid metabolism and detoxification. Ces1 ^-/- and TgCES1 mice will provide excellent tools for further study of the in vivo functions of Ces1/CES1 enzymes.