Adipocytes, Innate Immunity and Obesity: A Mini-Review

PRE-ADMISSION BARIATRIC SURGERY IS ASSOCIATED WITH REDUCED MORTALITY IN SURGICAL PATIENTS WITH SEPSIS

ABSTRACT

Background: Obesity is associated with higher 90-day mortality compared to nonobese surgical patients. Bariatric surgery (BS) can reduce obesity-related comorbidities, even in those with persistent obesity. Objective: Evaluate the impact of prior BS on sepsis outcomes in surgical patients with obesity. Setting: University Hospital, United States. Methods: A single-institution retrospective review of all surgical patients with sepsis (SOFA≥2) was conducted. Patients were grouped into people with obesity and prior BS (OB/BS; n = 48), people with obesity without BS (OB; n = 717), nonobese (NOB; n = 574), and nonobese with prior BS (NOB/BS; n = 27). Demographic data, comorbidities, and sepsis presentation were compared. The primary outcome was cumulative 90-day mortality and survival. Results: Most OB/BS patients underwent gastric bypass <5 years from admission (61%). The OB/BS group was younger, more likely to be female, and transferred from an outside hospital. The mean BMI was highest in the OB/BS group (46.3± 14.7 kg/m 2 , P < 0.0005). Charlson Comorbidity Index was lower in the OB/BS and NOB/BS groups (2 (1-4) and 2 (2-4), respectively, P = 0.0033). Cumulative 90-day mortality was significantly lower in the OB/BS cohort (20.8%, P = 0.002). The OB/BS cohort was more likely to die from intra-abdominal sepsis not amenable to source control (60% vs. 22.5% vs. 22.8% vs. 37.5%, P = 0.04). Compared to the other groups, 90-day survival was highest in the OB/BS cohort (log-rank P < 0.009). Conclusions: This study demonstrated improvement in 90-day survival in OB/BS patients despite higher BMIs. However, this group was more likely to die from intra-abdominal sources, likely reflecting surgical complexity in the setting of prior bypasses.

Forsythoside a as a potential therapeutic agent for non-alcoholic fatty liver disease: from target identification to in vitro and in vivo validation

Non-alcoholic fatty liver disease (NAFLD) is a long-term metabolic condition marked by unusual fat buildup in the liver, with an increasing occurrence worldwide. Forsythoside A (FA), a bioactive component of Forsythia suspensa, has anti-inflammatory, antioxidative, and hepatoprotective effects. This study investigates the mechanisms by which FA may treat NAFLD. Using bioinformatics tools, 35 potential targets of FA were identified, and a protein-protein interaction network was constructed. KEGG and GO enrichment analyses highlighted important pathways associated with NAFLD. The effects of FA were confirmed using both in vitro and in vivo NAFLD models. Matrix Metalloproteinase 9 (MMP9), and Tumour Necrosis Factor Alpha (TNFɑ), were identified as core targets. KEGG analysis showed that FA affects metabolic, TNF signalling, and insulin resistance pathways. In vitro and in vivo, FA reduced lipid accumulation and modulated TNFɑ, MMP9, and ALB expression. FA may treat NAFLD by modulating the TNFɑ/MMP9/ALB pathway, providing new therapeutic targets and insights for NAFLD treatment.

Lipedema: A Disease Triggered by M2 Polarized Macrophages?

Background/Objectives: Lipedema is a progressive disease that results in the bilateral and symmetrical accumulation of subcutaneous fat in the legs and/or arms, affecting almost exclusively women. Methods: A comprehensive review of the peer-reviewed literature was conducted between November 2024 and February 2025. Results: The pathophysiology of lipedema is complex and, especially in the early stages, shows similarities to obesity, involving adipocytes, adipose tissue-resident macrophages, and endothelial cells. In lipedema, systemic levels and the adipocyte expression of the classical adipokines adiponectin and leptin appear normal, while it remains unclear if markers of inflammation and oxidative stress are increased. Macrophages in the adipose tissue of patients have an anti-inflammatory M2 phenotype and express high levels of the scavenger receptor CD163. These cells affect adipogenesis and seem to have a central role in adipose tissue accumulation. Increased lymphatic and blood vessel permeability are comorbidities of lipedema that occur in early disease states and may contribute to disease progression. Conclusions: This review summarizes our current understanding of the pathophysiology of lipedema with a focus on the role of stromal vascular localized M2 macrophages.

Metabolic dysfunction in mice with adipocyte-specific ablation of the adenosine A2A receptor

It has been well established that adenosine plays a key role in the control of inflammation through G protein coupled receptors and recently shown that it can regulate thermogenesis. Here we investigated the specific requirements of the adenosine A2A receptor (A2AR) in mature adipocytes for thermogenic functionality and metabolic homeostasis. We generated fat tissue-specific adenosine A2AR KO mice to assess the influence of signaling through this receptor on brown and beige fat functionality, obesity, insulin sensitivity, inflammation, and liver function. Fat-specific A2AR KO and WT littermate mice were compared for potential differences in cold tolerance and energy metabolism. In addition, we measured glucose metabolism, AT inflammation, and liver phenotypes in mice of the two genotypes after exposure to a diet rich in fat. Our results provide novel evidence indicating that loss of the adenosine A2AR specifically in adipocytes is associated with cold intolerance and decreased oxygen consumption. Furthermore, mice with fat specific ablation of the A2AR exposed to a diet rich in fat showed increased propensity to obesity, decreased insulin sensitivity, elevated adipose tissue inflammation, and hepato-steatosis and hepato-steatitis. Overall, our data provide novel evidence that A2AR in mature adipocytes safeguards metabolic homeostasis, suggesting the possibility of targeting this receptor selectively in fat for the treatment of metabolic disease.

Type 2 Diabetes Mellitus: A Comprehensive Review of Pathophysiology, Comorbidities, and Emerging Therapies

Humans are perhaps evolutionarily engineered to get deeply addicted to sugar, as it not only provides energy but also helps in storing fats, which helps in survival during starvation. Additionally, sugars (glucose and fructose) stimulate the feel-good factor, as they trigger the secretion of serotonin and dopamine in the brain, associated with the reward sensation, uplifting the mood in general. However, when consumed in excess, it contributes to energy imbalance, weight gain, and obesity, leading to the onset of a complex metabolic disorder, generally referred to as diabetes. Type 2 diabetes mellitus (T2DM) is one of the most prevalent forms of diabetes, nearly affecting all age groups. T2DM is clinically diagnosed with a cardinal sign of chronic hyperglycemia (excessive sugar in the blood). Chronic hyperglycemia, coupled with dysfunctions of pancreatic β-cells, insulin resistance, and immune inflammation, further exacerbate the pathology of T2DM. Uncontrolled T2DM, a major public health concern, also contributes significantly toward the onset and progression of several micro- and macrovascular diseases, such as diabetic retinopathy, nephropathy, neuropathy, atherosclerosis, and cardiovascular diseases, including cancer. The current review discusses the epidemiology, causative factors, pathophysiology, and associated comorbidities, including the existing and emerging therapies related to T2DM. It also provides a future roadmap for alternative drug discovery for the management of T2DM.

Specific plasma biomarker signatures associated with patients undergoing surgery for back pain

BACKGROUND CONTEXT

Intervertebral disc degeneration (IDD) affects numerous people worldwide. The role of inflammation is increasingly recognized but remains incompletely resolved. Peripheral molecules could access neovascularized degenerated discs and contribute to the ongoing pathology.

PURPOSE

To assess a large array of plasma molecules in patients with IDD to identify biomarkers associated with specific spinal pathologies and prognostic biomarkers for the surgery outcome.

DESIGN

Prospective observational study combining clinical data and plasma measures.

PATIENT SAMPLE

Plasma samples were collected just before surgery. Extensive clinical data (age, sex, smoking status, Modic score, glomerular filtration rate, etc.) were extracted from clinical files from 83 patients with IDD undergoing spine surgery.

OUTCOME MEASURES

Recovery 2 months postsurgery as assessed by the treating neurosurgeon.

METHODS

Over 40 biological molecules were measured in patients' plasma using multiplex assays. Statistical analyses were performed to identify associations between biological and clinical characteristics (age, sex, Body Mass Index (BMI), smoking status, herniated disc, radiculopathy, myelopathy, stenosis, MODIC score, etc.) and plasma levels of biological molecules.

RESULTS

Plasma levels of Neurofilament Light chain (NfL) were significantly elevated in patients with myelopathy and spinal stenosis compared to herniated disc. Plasma levels of C- reactive protein (CRP), Neurofilament Light chain (NfL), and Serum Amyloid A (SAA) were negatively associated, while CCL22 levels were positively associated with an efficient recovery 2 months postsurgery.

CONCLUSIONS

Our results show that CRP and CCL22 plasma levels combined with the age of the IDD patient can predict the 2-month postsurgery recovery (Area Under the Curve [AUC]=0.883). Moreover, NfL could become a valuable monitoring tool for patients with spinal cord injuries.

The mesenteric adipokine SFRP5 alleviated intestinal epithelial apoptosis improving barrier dysfunction in Crohn's disease

The hypertrophic mesenteric adipose tissue (htMAT) of Crohn disease (CD) participates in inflammation through the expression of adipokines, but the exact mechanism of this action in the intestine is unknown. Here, we analyzed the expression of secreted frizzled-related protein 5 (SFRP5), an adipokine with cytoprotective effects, in htMAT and its role in CD. The results of this study revealed that the level of SFPR5 increased in the diseased MAT (htMAT) of CD patients and aggregated among intestinal epithelial cells in the diseased intestine and that it could ameliorate intestinal barrier dysfunction in tumor necrosis factor alpha (TNF-α)-stimulated colonic organoids and 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced mice at least in part through the inhibition of Wnt5a-mediated apoptosis in epithelial cells. This study elucidates possible mechanisms by which mesenteric adipokines influence the progression of enteritis and provides a new theoretical basis for the treatment of CD via the mesenteric pathway.

Testosterone and estradiol reduce inflammation of human macrophages induced by anti-SARS-CoV-2 IgG

COVID-19, the disease caused by SARS-CoV-2, particularly causes severe inflammatory disease in elderly, obese, and male patients. Since both aging and obesity are associated with decreased testosterone and estradiol expression, we hypothesized that decreased hormone levels contribute to excessive inflammation in the context of COVID-19. Previously, we and others have shown that hyperinflammation in severe COVID-19 patients is induced by the production of pathogenic anti-spike IgG antibodies that activate alveolar macrophages. Therefore, we developed an in vitro assay in which we stimulated human macrophages with viral stimuli, anti-spike IgG immune complexes, and different sex hormones. Treatment with levels of testosterone reflecting young adults led to a significant reduction in TNF and IFN-γ production by human macrophages. In addition, estradiol significantly attenuated the production of a very broad panel of cytokines, including TNF, IL-1β, IL-6, IL-10, and IFN-γ. Both testosterone and estradiol reduced the expression of Fc gamma receptors IIa and III, the two main receptors responsible for anti-spike IgG-induced inflammation. Combined, these findings indicate that sex hormones reduce the inflammatory response of human alveolar macrophages to specific COVID-19-associated stimuli, thereby providing a potential immunological mechanism for the development of severe COVID-19 in both older male and female patients.

Spatial Discrimination Limit Analysis of Macrophage Phagocytosis Between Target Antigens and Non-Target Objects Using Microcapillary Manipulation Assay

During phagocytosis, the FcGR-IgG bond is thought to be necessary to promote cell-membrane extension as the zipper mechanism. However, does this zipper mechanism provide a spatial antigen discrimination capability that allows macrophages to selectively phagocytose only antigens, especially for clusters with a mixture of antigens and non-antigens? To elucidate the ability and limitation of the zipper mechanism, we fed a coupled 2 μm IgG-coated and 4.5 μm non-coated polystyrene bead mixtures to macrophages and observed their phagocytosis. Macrophage engulfed the mixed clusters, including the 4.5 μm non-coated polystyrene part, indicating that the non-coated particles can be engulfed even without the zipper mechanism as far as coupled to the opsonized particles. In contrast, when the non-opsonized particle part was held by the microcapillary manipulation assay, macrophages pinched off the non-coated polystyrene particle part and internalized the opsonized particle part only. The results suggest that (1) an IgG-coated surface is needed to anchor phagocytosis by cell-membrane protrusion; however, (2) once the antibody-dependent cell phagocytosis is started, phagocytosis can proceed with the uncoated objects as the followers of the internalizing opsonized particles even without the support of the zipper mechanism. They may also indicate the concern of misleading the immune system to target unexpected objects because of their aggregation with target pathogens and the possibility of new medical applications to capture the non-opsonized target objects by the aggregation with small antigens to activate an immune response.

Unveiling the impact of TREM-2+ Macrophages in metabolic disorders

The Triggering Receptor Expressed on Myeloid cells 2 (TREM-2) has been widely known by its anti-inflammatory activity. It can be activated in response to microbes and tissue damage, leading to phagocytosis, autophagy, cell polarization and migration, counter inflammation, and tissue repair. So far, the receptor has been largely explored in neurodegenerative disorders, however, a growing number of studies have been investigating its contribution in different pathological conditions, including metabolic diseases, in which (resident) macrophages play a crucial role. In this regard, TREM-2 + macrophages have been implicated in the onset and development of obesity, atherosclerosis, and fibrotic liver disease. These macrophages can be detected in the brain, white adipose tissue, liver, and vascular endothelium. In this review we discuss how different murine models have been demonstrating the ability of such cells to contribute to tissue and body homeostasis by phagocytosing cellular debris and lipid structures, besides contributing to lipid homeostasis in metabolic diseases. Therefore, understanding the role of TREM-2 in metabolic disorders is crucial to expand our current knowledge concerning their immunopathology as well as to foster the development of more targeted therapies to treat such conditions.

Excessive or sustained endoplasmic reticulum stress: one of the culprits of adipocyte dysfunction in obesity

As the prevalence of obesity continues to rise globally, the research on adipocytes has attracted more and more attention. In the presence of nutrient overload, adipocytes are exposed to pressures such as hypoxia, inflammation, mechanical stress, metabolite, and oxidative stress that can lead to organelle dysfunction. Endoplasmic reticulum (ER) is a vital organelle for sensing cellular pressure, and its homeostasis is essential for maintaining adipocyte function. Under conditions of excess nutrition, ER stress (ERS) will be triggered by the gathering of abnormally folded proteins in the ER lumen, resulting in the activation of a signaling response known as the unfolded protein responses (UPRs), which is a response system to relieve ERS and restore ER homeostasis. However, if the UPRs fail to rescue ER homeostasis, ERS will activate pathways to damage cells. Studies have shown a role for disturbed activation of adipocyte ERS in the pathophysiology of obesity and its complications. Prolonged or excessive ERS in adipocytes can aggravate lipolysis, insulin resistance, and apoptosis and affect the bioactive molecule production. In addition, ERS also impacts the expression of some important genes. In view of the fact that ERS influences adipocyte function through various mechanisms, targeting ERS may be a viable strategy to treat obesity. This article summarizes the effects of ERS on adipocytes during obesity.

Anti-obesity and immunomodulatory effects of Allium hookeri leaves cultivated with artificial light of different intensities on immune-depressed obese mice

This study was conducted to evaluate the effects of Allium hookeri (AH) leaves cultivated with different light-emitting diode (LED) intensities (L: low, 100 μmol/m2/s; M: medium, 150 μmol/m2/s; H: high, 200 μmol/m2/s). Alliin concentration increased as light intensity increased in AH and showed the highest level at LED-H condition. The anti-obesity and immunomodulatory properties of AH were evaluated in a cyclophosphamide (CPA)-induced immunosuppressed obese animal model. C57BL/6 J mice were randomly divided into control (CON), high-fat diet (HFD) control (CON-H), negative control (NC), positive control (PC, β-glucan, 50 mg/kg body weight (BW)), AH L, M, and H groups. The three kinds of AH extracts were orally administered to the mice at 300 mg/kg BW for 2 weeks. Except for CON and CON-H, all the other groups were intraperitoneally treated with CPA. Epididymal and abdominal fat weight decreased as LED intensity increased while spleen weight increased in the AH groups. Serum glucose decreased as LED intensity increased in the AH groups and H group showed the lowest level. Triglycerides, total, and LDL-cholesterol levels decreased while HDL-cholesterol level increased in the AH groups compared to the NC group. Moreover, AH effectively reduced serum ALT and AST levels and increased the total white blood cell count, particularly elevating lymphocyte and monocyte levels. Furthermore, NK cell activity was higher in the AH groups. These findings suggest that AH cultivated at optimal LED intensity could be used as a novel biomedicine and in pharmacotherapy to treat related diseases to improve public health without any toxicity.

Contents of exosomes derived from adipose tissue and their regulation on inflammation, tumors, and diabetes

Adipose tissue (AT) serves as an energy-capacitive organ and performs functions involving paracrine- and endocrine-mediated regulation via extracellular vesicles (EVs) secretion. Exosomes, a subtype of EVs, contain various bioactive molecules with regulatory effects, such as nucleic acids, proteins, and lipids. AT-derived exosomes (AT-exos) include exosomes derived from various cells in AT, including adipocytes, adipose-derived stem cells (ADSCs), macrophages, and endothelial cells. This review aimed to comprehensively evaluate the impacts of different AT-exos on the regulation of physiological and pathological processes. The contents and functions of adipocyte-derived exosomes and ADSC-derived exosomes are compared simultaneously, highlighting their similarities and differences. The contents of AT-exos have been shown to exert complex regulatory effects on local inflammation, tumor dynamics, and insulin resistance. Significantly, differences in the cargoes of AT-exos have been observed among diabetes patients, obese individuals, and healthy individuals. These differences could be used to predict the development of diabetes mellitus and as therapeutic targets for improving insulin sensitivity and glucose tolerance. However, further research is needed to elucidate the underlying mechanisms and potential applications of AT-exos.

A systematic review on the applicability of cell-free DNA level as an obesity biomarker

Obesity has become a global health concern in recent decades. Utilizing biomarkers presents a promising approach to comprehensively monitor the progress of obesity and its associated health conditions. This review aims to synthesize the available evidence on the correlation between cfDNA level and obesity and to provide insights into the applicability of using cfDNA level as a tool for monitoring progression of obesity. Searches were performed in PubMed and Embase on April 1, 2022. Data and other relevant information were extracted and compiled into a structured table for further analysis. Among 1170 articles screened, 11 articles were included in this review and assessed qualitatively. The results demonstrated that existing evidence mainly focused on three populations, including healthy individuals, cancer patients and pregnant women. Majority of the studies on healthy individuals identified a significant association between cfDNA level and body weight status but not among cancer patients. Varying results were observed among pregnant women at different gestational trimesters. Our review summarized some preliminary evidence on the association between cfDNA level and obesity. More cohort studies in larger scale with comprehensive assessment have to be conducted to examine the applicability of cfDNA as a biomarker for severity and disease progression of obesity.

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

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

Obesity is associated with improved early survival but increased late mortality in surgical patients with Sepsis: A propensity matched analysis

BACKGROUND

While obesity is a risk factor for postoperative complications, its impact following sepsis is unclear. The primary objective of this study was to evaluate the association between obesity and mortality following admission to the surgical intensive care unit (SICU) with sepsis.

METHODS

We conducted a single center retrospective review of SICU patients grouped into obese (n = 766, body mass index ≥30 kg/m 2 ) and nonobese (n = 574; body mass index, 18-29.9 kg/m 2 ) cohorts. Applying 1:1 propensity matching for age, sex, comorbidities, sequential organ failure assessment, and transfer status, demographic data, comorbidities, and sepsis presentation were compared between groups. Primary outcomes included in-hospital and 90-day mortality, ICU length of stay, need for mechanical ventilation (IMV) and renal replacement therapy (RRT). p < 0.05 was considered significant.

RESULTS

Obesity associates with higher median ICU length of stay (8.2 vs. 5.6, p < 0.001), need for IMV (76% vs. 67%, p = 0.001), ventilator days (5 vs. 4, p < 0.004), and RRT (23% vs. 12%, p < 0.001). In-hospital (29% vs. 18%, p < 0.0001) and 90-day mortality (34% vs. 24%, p = 0.0006) was higher for obese compared with nonobese groups. Obesity independently predicted need for IMV (odds ratio [OR], 1.6; 95% confidence interval [CI], 1.2-2.1), RRT (OR, 2.2; 95% CI, 1.5-3.1), in-hospital (OR, 2.1; 95% CI, 1.5-2.8), and 90-day mortality (HR, 1.4; 95% CI, 1.1-1.8), after adjusting for sequential organ failure assessment, age, sex, and comorbidities. Comparative survival analyses demonstrate a paradoxical early survival benefit for obese patients followed by a rapid decline after 7 days (logrank p = 0.0009).

CONCLUSION

Obesity is an independent risk factor for 90-day mortality for surgical patients with sepsis, but its impact appeared later in hospitalization. Understanding differences in systemic responses between these cohorts may be important for optimizing critical care management.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level III.

Epigenetic and Molecular Alterations in Obesity: Linking CRP and DNA Methylation to Systemic Inflammation

Obesity is marked by excessive fat accumulation in the adipose tissue, which disrupts metabolic processes and causes chronic systemic inflammation. Commonly, body mass index (BMI) is used to assess obesity-related risks, predicting potential metabolic disorders. However, for a better clustering of obese patients, we must consider molecular and epigenetic changes which may be responsible for inflammation and metabolic changes. Our study involved two groups of patients, obese and healthy donors, on which routine analysis were performed, focused on BMI, leukocytes count, and C-reactive protein (CRP) and completed with global DNA methylation and gene expression analysis for genes involved in inflammation and adipogenesis. Our results indicate that obese patients exhibited elevated leukocytes levels, along with increased BMI and CRP. The obese group revealed a global hypomethylation and upregulation of proinflammatory genes, with adipogenesis genes following the same trend of being overexpressed. The study confirms that obesity is linked to systematic inflammation and metabolic dysfunction through epigenetic and molecular alterations. The CRP was correlated with the hypomethylation status in obese patients, and this fact may contribute to a better understanding of the roles of specific genes in adipogenesis and inflammation, leading to a better personalized therapy.

The Interplay between Obesity and Inflammation

Obesity is an important condition affecting the quality of life of numerous patients and increasing their associated risk for multiple diseases, including tumors and immune-mediated disorders. Inflammation appears to play a major role in the development of obesity and represents a central point for the activity of cellular and humoral components in the adipose tissue. Macrophages play a key role as the main cellular component of the adipose tissue regulating the chronic inflammation and modulating the secretion and differentiation of various pro- and anti-inflammatory cytokines. Inflammation also involves a series of signaling pathways that might represent the focus for new therapies and interventions. Weight loss is essential in decreasing cardiometabolic risks and the degree of associated inflammation; however, the latter can persist for long after the excess weight is lost, and can involve changes in macrophage phenotypes that can ensure the metabolic adjustment. A clear understanding of the pathophysiological processes in the adipose tissue and the interplay between obesity and chronic inflammation can lead to a better understanding of the development of comorbidities and may ensure future targets for the treatment of obesity.

What is the disease burden from childhood and adolescent obesity?: a narrative review

The prevalence of childhood and adolescent obesity has increased and exacerbated during the coronavirus disease 2019 pandemic, both in Korea and globally. Childhood and adolescent obesity poses significant risks for premature morbidity and mortality. The development of serious comorbidities depends not only on the duration of obesity but also on the age of onset. Obesity in children and adolescents affects almost all organ systems, including the endocrine, cardiovascular, gastrointestinal, reproductive, nervous, and immune systems. Obesity in children and adolescents affects growth, cognitive function, and psychosocial interactions during development, in addition to aggravating known adult comorbidities such as type 2 diabetes mellitus, hypertension, dyslipidemia, nonalcoholic fatty liver disease, obstructive sleep apnea, and cancer. Childhood and adolescent obesity are highly associated with increased cardiometabolic risk factors and prevalence of metabolic syndrome. The risk of cardiovascular and metabolic diseases in later life can be considerably decreased by even a small weight loss before the onset of puberty. Childhood and adolescent obesity is a disease that requires treatment and is associated with many comorbidities and disease burdens. Therefore, early detection and therapeutic intervention are crucial.

Molecular and pathophysiological relationship between obesity and chronic inflammation in the manifestation of metabolic dysfunctions and their inflammation‑mediating treatment options (Review)

Obesity reaches up to epidemic proportions globally and increases the risk for a wide spectrum of co‑morbidities, including type‑2 diabetes mellitus (T2DM), hypertension, dyslipidemia, cardiovascular diseases, non‑alcoholic fatty liver disease, kidney diseases, respiratory disorders, sleep apnea, musculoskeletal disorders and osteoarthritis, subfertility, psychosocial problems and certain types of cancers. The underlying inflammatory mechanisms interconnecting obesity with metabolic dysfunction are not completely understood. Increased adiposity promotes pro‑inflammatory polarization of macrophages toward the M1 phenotype, in adipose tissue (AT), with subsequent increased production of pro‑inflammatory cytokines and adipokines, inducing therefore an overall, systemic, low‑grade inflammation, which contributes to metabolic syndrome (MetS), insulin resistance (IR) and T2DM. Targeting inflammatory mediators could be alternative therapies to treat obesity, but their safety and efficacy remains to be studied further and confirmed in future clinical trials. The present review highlights the molecular and pathophysiological mechanisms by which the chronic low‑grade inflammation in AT and the production of reactive oxygen species lead to MetS, IR and T2DM. In addition, focus is given on the role of anti‑inflammatory agents, in the resolution of chronic inflammation, through the blockade of chemotactic factors, such as monocytes chemotractant protein‑1, and/or the blockade of pro‑inflammatory mediators, such as IL‑1β, TNF‑α, visfatin, and plasminogen activator inhibitor‑1, and/or the increased synthesis of adipokines, such as adiponectin and apelin, in obesity‑associated metabolic dysfunction.

Therapeutic targeting of white adipose tissue metabolic dysfunction in obesity: mechanisms and opportunities

White adipose tissue is not only a highly heterogeneous organ containing various cells, such as adipocytes, adipose stem and progenitor cells, and immune cells, but also an endocrine organ that is highly important for regulating metabolic and immune homeostasis. In individuals with obesity, dynamic cellular changes in adipose tissue result in phenotypic switching and adipose tissue dysfunction, including pathological expansion, WAT fibrosis, immune cell infiltration, endoplasmic reticulum stress, and ectopic lipid accumulation, ultimately leading to chronic low-grade inflammation and insulin resistance. Recently, many distinct subpopulations of adipose tissue have been identified, providing new insights into the potential mechanisms of adipose dysfunction in individuals with obesity. Therefore, targeting white adipose tissue as a therapeutic agent for treating obesity and obesity-related metabolic diseases is of great scientific interest. Here, we provide an overview of white adipose tissue remodeling in individuals with obesity including cellular changes and discuss the underlying regulatory mechanisms of white adipose tissue metabolic dysfunction. Currently, various studies have uncovered promising targets and strategies for obesity treatment. We also outline the potential therapeutic signaling pathways of targeting adipose tissue and summarize existing therapeutic strategies for antiobesity treatment including pharmacological approaches, lifestyle interventions, and novel therapies.

Obesity correlates with the immunosuppressive ILC2s-MDSCs axis in advanced breast cancer

AIM

We investigated the relationship between the group 2 innate lymphoid cells (ILC2s)-myeloid-derived suppressor cells (MDSCs) axis and obesity-related breast cancer.

METHODS

Fifty-eight patients with breast cancer who had first relapse and metastasis between January 2019 and August 2021 were enrolled. The proportions of ILC2s and MDSCs in blood and the levels of cytokines in serum were detected with flow cytometry. Correlation analysis among clinical characteristics (such as body mass index [BMI]), cytokines, ILC2s, and MDSCs was conducted.

RESULTS

There was a significant difference in the proportions of ILC2s and MDSCs between the high BMI group and the normal BMI group (p < .05). In the triple-negative breast cancer (TNBC) patients, the proportions of ILC2s and MDSCs in the obese group were significantly higher than those in the nonobese group (p < .05). In all breast cancer patients, there was a positive correlation between BMI and the ILC2s-MDSCs axis (p < .05). However, there was no correlation observed between the number of metastases, progression-free survival, and the ILC2s-MDSCs axis (p > .05). Additionally, ILC2s showed positive correlations with MDSCs, interleukin-5 (IL-5), IL-10, IL-17A, (PD-L1), programmed cell death 2 ligand 2 (PD-L2), and molecular typing (p < .05). Similarly, MDSCs exhibited positive correlations with IL-5, IL-8, IL-9, IL-17A, PD-L1, and PD-L2 (p < .05). In patients with TNBC, there was a positive correlation between BMI and IL-5 (p < .05).

CONCLUSION

Conclusively, obesity may enhance the immunosuppressive effect of the ILC2-MDSC axis in advanced breast cancer. IL-5 may play a vital role in the ILC2-MDSC axis and obesity in TNBC.

Physical and respiratory therapy in the critically ill patient with obesity: a narrative review

Obesity has become increasingly prevalent in the intensive care unit, presenting a significant challenge for healthcare systems and professionals, including rehabilitation teams. Caring for critically ill patients with obesity involves addressing complex issues. Despite the well-established and safe practice of early mobilization during critical illness, in rehabilitation matters, the diverse clinical disturbances and scenarios within the obese patient population necessitate a comprehensive understanding. This includes recognizing the importance of metabolic support, both non-invasive and invasive ventilatory support, and their weaning processes as essential prerequisites. Physiotherapists, working collaboratively with a multidisciplinary team, play a crucial role in ensuring proper assessment and functional rehabilitation in the critical care setting. This review aims to provide critical insights into the key management and rehabilitation principles for obese patients in the intensive care unit.

Adipose Tissue Inflammation: Linking Physiological Stressors to Disease Susceptibility

The study of adipose tissue (AT) is enjoying a renaissance. White, brown, and beige adipocytes are being investigated in adult animals, and the critical roles of small depots like perivascular AT are becoming clear. But the most profound revision of the AT dogma has been its cellular composition and regulation. Single-cell transcriptomic studies revealed that adipocytes comprise well under 50% of the cells in white AT, and a substantial portion of the rest are immune cells. Altering the function of AT resident leukocytes can induce or correct metabolic syndrome and, more surprisingly, alter adaptive immune responses to infection. Although the field is dominated by obesity research, conditions such as rapid lipolysis, infection, and heat stress impact AT immune dynamics as well. Recent findings in rodents lead to critical questions that should be explored in domestic livestock as potential avenues for improved animal resilience to stressors, particularly as animals age.

Hypertension in non-obese children and BMI in adulthood: the Bogalusa heart study

OBJECTIVE

This study explored the association between hypertension(HTN) in non-obese children body mass index (BMI) in adulthood.

METHODS

A retrospective analysis of 1111 participants from the Bogalusa Heart Study was conducted, in which data on hypertension history during childhood in non-obese children, anthropometric and cardiovascular risk factors and other indicators from cross-sectional examinations in adulthood were collected. BMI was used as both a continuous and a categorical variable, and multivariate linear regression modelling and logistic regression modelling were used.

RESULTS

Of the 1111 participants finally enrolled, 40 (3.60%) had HTN during childhood. After adjusting for demographic characteristics, lipid, glucose and insulin levels in childhood, and smoking status, alcohol intake, and disease history as adults, HTN among non-obese children was positively associated with BMI in adulthood (β = 2.64 kg/m2, 95% CI: 0.88-4.40, P = 0.0033), and the odds of being overweight or obese was 3.71 times higher in the group with a history of hypertension in childhood than those without a history of HTN(95% CI: 1.11-12.46, P = 0.0337).

CONCLUSION

Among non-obese children, hypertension is at risk for higher levels of BMI in adulthood. Identifying and controlling blood pressure and childhood may aid in the prevention of adult obesity.

Understanding the Consequences of Fatty Bone and Fatty Muscle: How the Osteosarcopenic Adiposity Phenotype Uncovers the Deterioration of Body Composition

Adiposity is central to aging and several chronic diseases. Adiposity encompasses not just the excess adipose tissue but also body fat redistribution, fat infiltration, hypertrophy of adipocytes, and the shifting of mesenchymal stem cell commitment to adipogenesis. Bone marrow adipose tissue expansion, inflammatory adipokines, and adipocyte-derived extracellular vesicles are central to the development of osteopenic adiposity. Adipose tissue infiltration and local adipogenesis within the muscle are critical in developing sarcopenic adiposity and subsequent poorer functional outcomes. Ultimately, osteosarcopenic adiposity syndrome is the result of all the processes noted above: fat infiltration and adipocyte expansion and redistribution within the bone, muscle, and adipose tissues, resulting in bone loss, muscle mass/strength loss, deteriorated adipose tissue, and subsequent functional decline. Increased fat tissue, typically referred to as obesity and expressed by body mass index (the latter often used inadequately), is now occurring in younger age groups, suggesting people will live longer with the negative effects of adiposity. This review discusses the role of adiposity in the deterioration of bone and muscle, as well as adipose tissue itself. It reveals how considering and including adiposity in the definition and diagnosis of osteopenic adiposity, sarcopenic adiposity, and osteosarcopenic adiposity will help in better understanding the pathophysiology of each and accelerate possible therapies and prevention approaches for both relatively healthy individuals or those with chronic disease.

Prognostic role of computed tomography analysis using deep learning algorithm in patients with chronic hepatitis B viral infection

BACKGROUND/AIMS

The prediction of clinical outcomes in patients with chronic hepatitis B (CHB) is paramount for effective management. This study aimed to evaluate the prognostic value of computed tomography (CT) analysis using deep learning algorithms in patients with CHB.

METHODS

This retrospective study included 2,169 patients with CHB without hepatic decompensation who underwent contrast-enhanced abdominal CT for hepatocellular carcinoma (HCC) surveillance between January 2005 and June 2016. Liver and spleen volumes and body composition measurements including subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), and skeletal muscle indices were acquired from CT images using deep learning-based fully automated organ segmentation algorithms. We assessed the significant predictors of HCC, hepatic decompensation, diabetes mellitus (DM), and overall survival (OS) using Cox proportional hazard analyses.

RESULTS

During a median follow-up period of 103.0 months, HCC (n=134, 6.2%), hepatic decompensation (n=103, 4.7%), DM (n=432, 19.9%), and death (n=120, 5.5%) occurred. According to the multivariate analysis, standardized spleen volume significantly predicted HCC development (hazard ratio [HR]=1.01, P=0.025), along with age, sex, albumin and platelet count. Standardized spleen volume (HR=1.01, P<0.001) and VAT index (HR=0.98, P=0.004) were significantly associated with hepatic decompensation along with age and albumin. Furthermore, VAT index (HR=1.01, P=0.001) and standardized spleen volume (HR=1.01, P=0.001) were significant predictors for DM, along with sex, age, and albumin. SAT index (HR=0.99, P=0.004) was significantly associated with OS, along with age, albumin, and MELD.

CONCLUSION

Deep learning-based automatically measured spleen volume, VAT, and SAT indices may provide various prognostic information in patients with CHB.

Metabolomic analysis of lipid changes in Bombyx mori infected with Nosema bombycis

The silkworm (Bombyx mori) is a model species of lepidopteran insect. Microsporidium spp. are obligate intracellular eukaryotic parasites. Infection by the microsporidian Nosema bombycis (Nb) results in an outbreak of Pébrine disease in silkworms and causes substantial losses to the sericulture industry. It has been suggested that Nb depends on nutrients from host cells for spore growth. However, little is known about changes in lipid levels after Nb infection. In this study, ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was performed to analyze the effect of Nb infection on lipid metabolism in the midgut of silkworms. A total of 1601 individual lipid molecules were detected in the midgut of silkworms, of which 15 were significantly decreased after Nb challenge. Classification, chain length, and chain saturation analysis revealed that these 15 differential lipids can be classified into different lipid subclasses, of which 13 belong to glycerol phospholipid lipids and two belong to glyceride esters. The results indicated that Nb uses the host lipids to complete its own replication, and the acquisition of host lipid subclasses is selective; not all lipid subclasses are required for microsporidium growth or proliferation. Based on lipid metabolism data, phosphatidylcholine (PC) was found to be an important nutrient for Nb replication. Diet supplementation with lecithin substantially promoted the replication of Nb. Knockdown and overexpression of the key enzyme phosphatidate phosphatase (PAP) and phosphatidylcholine (Bbc) for PC synthesis also confirmed that PC is necessary for Nb replication. Our results showed that most lipids in the host midgut decreased when silkworms were infected with Nb. Reduction of or supplementation with PC may be a strategy to suppress or promote microsporidial replication.

Differences in the metabolic profiles of brown and white adipocytes based on secretomics

Brown adipocytes and white adipocytes play important roles in systemic metabolism and energy homeostasis. Recent studies have demonstrated that white adipocytes and brown adipocytes secrete numerous adipokines and thus act as endocrine cells. However, differences in the metabolites secreted from white adipocytes and brown adipocytes have never been reported. In this study, we assessed the metabolites secreted from white adipocytes and brown adipocytes. In total, the levels of 47 metabolites in brown adipocytes were significantly different from those in white adipocytes, with 31 high and 16 low in brown adipocytes as compared with those in white adipocytes. We classified these secreted metabolites as amino acids and peptides, fatty acids, and conjugates, glycerophosphocholines, furanones, and trichloroacetic acids. In addition, we identified the glycerophospholipid metabolism activated in white adipocytes, and these differentially expressed metabolites were associated with the mitogen-activated protein kinase pathway and Janus kinase-signal transducer and activator of transcription signaling pathway according to the Ingenuity Pathway Analysis (IPA) software analysis. This study revealed novel metabolites secreted from brown adipocytes and white adipocytes, and these metabolites from adipocytes may perform specific biological functions based on the type of adipocyte that secretes them, and this forms the material basis of the interaction between adipocytes and other cells.

Obesity and recurrent miscarriage: The interconnections between adipose tissue and the immune system

Currently, obesity is considered a global public health problem. It is the main risk factor for noncommunicable diseases and reproductive complications, such as recurrent miscarriage (RM). RM affects approximately 1% of couples of reproductive age, and recent studies suggest that its prevalence is increasing. Immunological abnormalities may be responsible for a significant number of cases of unexplained RM. Obesity is recognized as a chronic low-grade inflammatory condition. The accumulation of fat in obese adipose tissue promotes changes in the local and systemic immune response. Adipokines, exosomes, micro-RNAs, lipids, and other factors released or secreted by adipose tissue are responsible for the interconnection between obesity and the immune system. Obesity-induced dysregulation of the innate and acquired immune response is also involved in the immunopathology of pregnancy loss in patients with unexplained RM. Therefore, understanding the communication pathways between maternal adipose tissue and the immune response in women living with obesity and RM is an important objective. Thus, diagnostic tools and new immunomodulatory therapies may be proposed for the management of patients with concurrent obesity and RM.

Targeting Metabolic Syndrome in Hidradenitis Suppurativa by Phytochemicals as a Potential Complementary Therapeutic Strategy

Hidradenitis suppurativa (HS) is a chronic inflammatory disease characterized by the appearance of painful inflamed nodules, abscesses, and pus-draining sinus tracts in the intertriginous skin of the groins, buttocks, and perianal and axillary regions. Despite its high prevalence of ~0.4-1%, therapeutic options for HS are still limited. Over the past 10 years, it has become clear that HS is a systemic disease, associated with various comorbidities, including metabolic syndrome (MetS) and its sequelae. Accordingly, the life expectancy of HS patients is significantly reduced. MetS, in particular, obesity, can support sustained inflammation and thereby exacerbate skin manifestations and the chronification of HS. However, MetS actually lacks necessary attention in HS therapy, underlining the high medical need for novel therapeutic options. This review directs attention towards the relevance of MetS in HS and evaluates the potential of phytomedical drug candidates to alleviate its components. It starts by describing key facts about HS, the specifics of metabolic alterations in HS patients, and mechanisms by which obesity may exacerbate HS skin alterations. Then, the results from the preclinical studies with phytochemicals on MetS parameters are evaluated and the outcomes of respective randomized controlled clinical trials in healthy people and patients without HS are presented.

Browning of Mesenteric White Adipose Tissue in Crohn's Disease: A New Pathological Change and Therapeutic Target

BACKROUND

Hypertrophic mesenteric adipose tissue [htMAT] is a distinctive hallmark of Crohn's disease [CD], and it affects enteritis via inflammatory adipokine secretion by dysfunctional white adipocytes. White adipocytes can become beige adipocytes, which are characterized by active lipid consumption and favourable endocrine function, via white adipocyte browning. Our study aimed to determine whether white adipocyte browning occurs in htMAT and its role in CD.

METHODS

White adipocyte browning was examined in MAT samples from CD patients and controls. Human MAT explants and primary mesenteric adipocytes were cultured for in vitro experiments. Mice with 2,4,6-trinitrobenzenesulphonic acid solution [TNBS]-induced colitis were used for in vivo studies. A β3-adrenergic receptor agonist [CL316,243] was used to induce white adipocyte browning, and IL-4/STAT6 signalling was analysed to explore the mechanism underlying the anti-inflammatory activity of beige adipocytes.

RESULTS

White adipocyte browning was observed in htMAT from CD patients, as shown by the appearance of uncoupling protein 1 [UCP1]-positive multilocular [beige] adipocytes with lipid-depleting activity and anti-inflammatory endocrine profiles. Both human MAT and primary mesenteric adipocytes from CD patients and controls could be induced to undergo browning, which increased their lipid-depleting and anti-inflammatory activities in vitro. Inducing MAT browning ameliorated mesenteric hypertrophy and inflammation as well as colitis in TNBS-treated mice in vivo. The anti-inflammatory activity of beige adipocytes was at least partially related to STAT6 signalling activation via the autocrine and paracrine effects of IL-4.

CONCLUSION

White adipocyte browning is a newly identified pathological change in htMAT of CD patients and a possible therapeutic target.

Asprosin contributes to nonalcoholic fatty liver disease through regulating lipid accumulation and inflammatory response via AMPK signaling

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a primary contributor to liver-related morbidity and mortality. Asprosin has been reported to be implicated in NAFLD.

AIMS

This work is to illuminate the effects of Asprosin on NAFLD and the possible downstream mechanism.

MATERIALS & METHODS

The weight of NAFLD mice induced by a high-fat diet was detected. Quantitative reverse-transcription polymerase chain reaction (RT-qPCR) examined serum Asprosin expression. RT-qPCR and western blot analysis examined Asprosin expression in mice liver tissues. Intraperitoneal glucose tolerance test (IPGTT) and intraperitoneal insulin tolerance test (IPITT) were implemented. Biochemical kits tested liver enzyme levels in mice serum and liver tissues. Hematoxylin and eosin staining evaluated liver histology. Liver weight was also tested and oil red O staining estimated lipid accumulation. RT-qPCR and western blot analysis analyzed the expression of gluconeogenesis-, fatty acid biosynthesis-, fatty acid oxidation-, and inflammation-associated factors. Besides, western blot analysis examined the expression of AMP-activated protein kinase (AMPK)/p38 signaling-associated factors. In palmitic acid (PA)-treated mice hepatocytes, RT-qPCR and western blot analysis examined Asprosin expression. Lipid accumulation, gluconeogenesis, fatty acid biosynthesis, fatty acid oxidation, and inflammation were appraised again.

RESULTS

Asprosin was overexpressed in the serum and liver tissues of NAFLD mice and PA-treated mice hepatocytes. Asprosin interference reduced mice body and liver weight, improved glucose tolerance and diminished liver injury in vivo. Asprosin knockdown alleviated lipid accumulation and inflammatory infiltration both in vitro and in vivo. Additionally, Asprosin absence activated AMPK/p38 signaling and AMPK inhibitor Compound C reversed the impacts of Asprosin on lipid accumulation and inflammatory response.

CONCLUSION

Collectively, Asprosin inhibition suppressed lipid accumulation and inflammation to obstruct NAFLD through AMPK/p38 signaling.

Neural innervation in adipose tissue, gut, pancreas, and liver

Efficient communication between the brain and peripheral organs is indispensable for regulating physiological function and maintaining energy homeostasis. The peripheral nervous system (PNS) in vertebrates, consisting of the autonomic and somatic nervous systems, bridges the peripheral organs and the central nervous system (CNS). Metabolic signals are processed by both vagal sensory nerves and somatosensory nerves. The CNS receives sensory inputs via ascending nerves, serves as the coordination and integration center, and subsequently controls internal organs and glands via descending nerves. The autonomic nervous system consists of sympathetic and parasympathetic branches that project peripheral nerves into various anatomical locations to regulate the energy balance. Sympathetic and parasympathetic nerves typically control the reflexive and involuntary functions in organs. In this review article, we outline the innervation of adipose tissue, gut, pancreas, and liver, to illustrate the neurobiological basis of central-peripheral interactions. We emphasize the importance of understanding the functional atlas of neural control of energy metabolism, and more importantly, provide potential avenues for further research in this area.

A single nuclei atlas of aging human abdominal subcutaneous white adipose tissue

White adipose tissue (WAT) is a robust energy storage and endocrine organ critical for maintaining metabolic health as we age. Our aim was to identify cell-specific transcriptional aberrations that occur in WAT with aging. We leveraged full-length snRNA-Seq to characterize the cellular landscape of human subcutaneous WAT in a prospective cohort of 10 Younger (≤ 30 years) and 10 Older individuals (≥ 65 years) balanced for sex and body mass index (BMI). We highlight that aging WAT is associated with adipocyte hypertrophy, increased proportions of resident macrophages (M2), an upregulated innate immune response and senescence profiles in specific adipocyte populations, highlighting CXCL14 as a biomarker of this process. We also identify novel markers of pre-adipocytes and track their expression levels through pre-adipocyte differentiation. We propose that aging WAT is associated with low-grade inflammation that is managed by a foundation of innate immunity to preserve the metabolic health of the WAT.

Leptin: A Heavyweight Player in Obesity-Related Cancers

Obesity, defined as the abnormal or excessive expansion of white adipose tissue, has reached pandemic proportions and is recognized as an important health concern since it is a common root for several comorbidities, including malignancies. Indeed, the current knowledge of the white adipose tissue, which shifts its role from an energy storage tissue to an important endocrine and metabolic organ, has opened up new avenues for the discovery of obesity's effects on tumor biology. In this review, we will report the epidemiological studies concerning the strong impact of obesity in several types of cancer and describe the mechanisms underlying the heterotypic signals between cancer cell lines and adipocytes, with particular emphasis on inflammation, the insulin/IGF-1 axis, and adipokines. Among the adipokines, we will further describe the in vitro, in vivo, and clinical data concerning the role of leptin, recognized as one of the most important mediators of obesity-associated cancers. In fact, leptin physiologically regulates energy metabolism, appetite, and reproduction, and several studies have also described the role of leptin in affecting cancer development and progression. Finally, we will summarize the newest pharmacological strategies aimed at mitigating the protumorigenic effects of leptin, underlining their mechanisms of action.

What's gut got to do with it? The role of the microbiota and inflammation in the development of adiposity and obesity

Obesity is a complex and heterogeneous disease characterized by increased adiposity, ie, the accumulation of lipids and the growth of adipose tissue. In this mini-review, we explore the important role of the gut microbiota and immune system in the development of adiposity. Dysbiosis of the microbiota leads to increased permeability of the gut barrier and bacterial products in the bloodstream, which triggers metabolic inflammation of adipose tissue, muscle, and liver. Inflammation in these highly metabolic organs exacerbates adiposity and contributes to the development of comorbidities associated with obesity. Studies in animal models that manipulate the microbiota and/or inflammation have shown promise in the treatment of obesity.

Consumption of Common Bean Suppresses the Obesogenic Increase in Adipose Depot Mass: Impact of Dose and Biological Sex

Obesity prevention is stated as a simple objective in the public health guidelines of most countries: avoid adult weight gain. However, the success of the global population in accomplishing this goal is limited as reflected in the persisting pandemic of overweight and obesity. While many intervention strategies have been proposed, most are directed at mitigating the consequences of obesity. Efforts intended to prevent unintentional weight gain and associated adiposity are termed anti-obesogenic. Herein, evidence is presented that a neglected category of foods, pulses, i.e., grain legumes, have anti-obesogenic activity. Using a preclinical mouse model of obesity, a dose-response study design in animals of both biological sexes, and cooked, freeze-dried, and milled common bean as a representative pulse, data are presented showing that the rate of body weight gain is slowed, and fat accumulation is suppressed when 70% of the dietary protein is provided from common bean. These anti-obesogenic effects are reduced at lower amounts of common bean (17.5% or 35%). The anti-obesogenic responsiveness is greater in female than in male mice. RNA sequence analysis indicates that the sex-related differences extend to gene expression patterns, particularly those related to immune regulation within adipose tissue. In addition, our findings indicate the potential value of a precision nutrition approach for human intervention studies that identify "pulse anti-obesogenic responders". A precision approach may reduce the concentration of pulses required in the diet for benefits, but candidate biomarkers of responsivity to pulse consumption remain to be determined.

Adipocyte-specific FXR-deficiency protects adipose tissue from oxidative stress and insulin resistance and improves glucose homeostasis

OBJECTIVE

Obesity is associated with metabolic dysfunction of white adipose tissue (WAT). Activated adipocytes secrete pro-inflammatory cytokines resulting in the recruitment of pro-inflammatory macrophages, which contribute to WAT insulin resistance. The bile acid (BA)-activated nuclear Farnesoid X Receptor (FXR) controls systemic glucose and lipid metabolism. Here, we studied the role of FXR in adipose tissue function.

METHODS

We first investigated the immune phenotype of epididymal WAT (eWAT) from high fat diet (HFD)-fed whole-body FXR-deficient (FXR-/-) mice by flow cytometry and gene expression analysis. We then generated adipocyte-specific FXR-deficient (Ad-FXR-/-) mice and analyzed systemic and eWAT metabolism and immune phenotype upon HFD feeding. Transcriptomic analysis was done on mature eWAT adipocytes from HFD-fed Ad-FXR-/- mice.

RESULTS

eWAT from HFD-fed whole-body FXR-/- and Ad-FXR-/- mice displayed decreased pro-inflammatory macrophage infiltration and inflammation. Ad-FXR-/- mice showed lower blood glucose concentrations, improved systemic glucose tolerance and WAT insulin sensitivity and oxidative stress. Transcriptomic analysis identified Gsta4, a modulator of oxidative stress in WAT, as the most upregulated gene in Ad-FXR-/- mouse adipocytes. Finally, chromatin immunoprecipitation analysis showed that FXR binds the Gsta4 gene promoter.

CONCLUSIONS

These results indicate a role for the adipocyte FXR-GSTA4 axis in controlling HFD-induced inflammation and systemic glucose homeostasis.

Susceptibility of Fat Tissue to SARS-CoV-2 Infection in Female hACE2 Mouse Model

The coronavirus disease (COVID-19) is a highly contagious viral illness caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). COVID-19 has had a catastrophic effect globally causing millions of deaths worldwide and causing long-lasting health complications in COVID-19 survivors. Recent studies including ours have highlighted that adipose tissue can act as a reservoir where SARS-CoV-2 can persist and cause long-term health problems. Here, we evaluated the effect of SARS-CoV-2 infection on adipose tissue physiology and the pathogenesis of fat loss in a murine COVID-19 model using humanized angiotensin-converting enzyme 2 (hACE2) mice. Since epidemiological studies reported a higher mortality rate of COVID-19 in males than in females, we examined hACE2 mice of both sexes and performed a comparative analysis. Our study revealed for the first time that: (a) viral loads in adipose tissue and the lungs differ between males and females in hACE2 mice; (b) an inverse relationship exists between the viral loads in the lungs and adipose tissue, and it differs between males and females; and (c) CoV-2 infection alters immune signaling and cell death signaling differently in SARS-CoV-2 infected male and female mice. Overall, our data suggest that adipose tissue and loss of fat cells could play important roles in determining susceptibility to CoV-2 infection in a sex-dependent manner.

Therapeutics of Extracellular Vesicles in Cardiocerebrovascular and Metabolic Diseases

Extracellular vesicles (EVs) are nanoscale membranous vesicles containing DNA, RNA, lipids, and proteins, which play versatile roles in intercellular communications. EVs are increasingly being recognized as the promising therapeutic agents for many diseases, including cardiocerebrovascular and metabolic diseases, due to their ability to deliver functional and therapeutical molecules. In this chapter, the biological characteristics and functions of EVs are briefly summarized. Importantly, the current state of applying EVs in the prevention and treatment of cardiocerebrovascular and metabolic diseases, including myocardial infarction, atrial fibrillation, myocardial hypertrophy, stroke, diabetes, Alzheimer's disease, fatty liver, obesity, thyroid diseases, and osteoporosis, is discussed. Lastly, the challenges and prospects related to the preclinical and clinical application of EVs receive a particular focus.

Obesity and Risk for Lymphoma: Possible Role of Leptin

Obesity, which is considered a pandemic due to its high prevalence, is a risk factor for many types of cancers, including lymphoma, through a variety of mechanisms by promoting an inflammatory state. Specifically, over the last few decades, obesity has been suggested not only to increase the risk of lymphoma but also to be associated with poor clinical outcomes and worse responses to different treatments for those diseases. Within the extensive range of proinflammatory mediators that adipose tissue releases, leptin has been demonstrated to be a key adipokine due to its pleotropic effects in many physiological systems and diseases. In this sense, different studies have analyzed leptin levels and leptin/leptin receptor expressions as a probable bridge between obesity and lymphomas. Since both obesity and lymphomas are prevalent pathophysiological conditions worldwide and their incidences have increased over the last few years, here we review the possible role of leptin as a promising proinflammatory mediator promoting lymphomas.

Neuroimmune regulation of white adipose tissues

The white adipose tissues (WAT) are located in distinct depots throughout the body. They serve as an energy reserve, providing fatty acids for other tissues via lipolysis when needed, and function as an endocrine organ to regulate systemic metabolism. Their activities are coordinated through intercellular communications among adipocytes and other cell types such as residential and infiltrating immune cells, which are collectively under neuronal control. The adipocytes and immune subtypes including macrophages/monocytes, eosinophils, neutrophils, group 2 innate lymphoid cells (ILC2s), T and B cells, dendritic cells (DCs), and natural killer (NK) cells display cellular and functional diversity in response to the energy states and contribute to metabolic homeostasis and pathological conditions. Accumulating evidence reveals that neuronal innervations control lipid deposition and mobilization via regulating lipolysis, adipocyte size, and cellularity. Vice versa, the neuronal innervations and activity are influenced by cellular factors in the WAT. Though the literature describing adipose tissue cells is too extensive to cover in detail, we strive to highlight a selected list of neuronal and immune components in this review. The cell-to-cell communications and the perspective of neuroimmune regulation are emphasized to enlighten the potential therapeutic opportunities for treating metabolic disorders.

Role of microRNA in Endocrine Disruptor-Induced Immunomodulation of Metabolic Health

The prevalence of poor metabolic health is growing exponentially worldwide. This condition is associated with complex comorbidities that lead to a compromised quality of life. One of the contributing factors recently gaining attention is exposure to environmental chemicals, such as endocrine-disrupting chemicals (EDCs). Considerable evidence suggests that EDCs can alter the endocrine system through immunomodulation. More concerning, EDC exposure during the fetal development stage has prominent adverse effects later in life, which may pass on to subsequent generations. Although the mechanism of action for this phenomenon is mostly unexplored, recent reports implicate that non-coding RNAs, such as microRNAs (miRs), may play a vital role in this scenario. MiRs are significant contributors in post-transcriptional regulation of gene expression. Studies demonstrating the immunomodulation of EDCs via miRs in metabolic health or towards the Developmental Origins of Health and Disease (DOHaD) Hypothesis are still deficient. The aim of the current review was to focus on studies that demonstrate the impact of EDCs primarily on innate immunity and the potential role of miRs in metabolic health.

What Is the Role of Body Composition Assessment in HCC Management?

In the last decade, body composition (BC) assessment has emerged as an innovative tool that can offer valuable data concerning nutritional status in addition to the information provided by the classical parameters (i.e., body mass index, albumin). Furthermore, published data have revealed that different types of body composition are associated with different outcomes. For example, abnormalities of skeletal muscle, a common finding in cirrhotic and oncologic patients, are associated with poor outcome (i.e., high morbidity and high mortality). The disposition (visceral/subcutaneous adipose tissue) and radiodensity of adipose tissue proved to also be determinant factors for HCC outcome. Despite all the advantages, BC assessment is not part of the standard pre-therapeutic workup. The main reasons are the high heterogeneity of data, the paucity of prospective studies, the lack of a standard assessment method, and the interpopulation variation of BC. This paper aims to review the available evidence regarding the role of BC as a prognostic tool in the HCC population undergoing various therapies.

SARS-CoV-2 and Influenza Vaccines in People with Excessive Body Mass-A Narrative Review

In the face of a growing number of overweight people and two widely known viral diseases, SARS-CoV-2 and influenza, it is crucial to be aware of the impact of excess body weight on immunisation against these diseases. The aim of this review is to show the effectiveness of SARS-CoV-2 and influenza vaccines in overweight and obese patients. Excessive adipose tissue releases cytokines and maintains local hypoxia, which causes persistent low-grade inflammation. These factors make excess body mass patients' immune systems weaker. Under such conditions, the humoral response becomes less efficient, leading to a weakened ability to fight against infection and an increased risk of developing lower antibody titres. Vaccines help to reduce morbidity both in normal-weight and excess body mass people, although most studies show that patients with higher BMI tend to lose the antibodies produced more quickly. It is shown that the most effective vaccines (in terms of preventing the infection and potential post-illness complications) are the BNT162b2 vaccine against SARS-CoV-2 and the inactivated influenza vaccine against influenza among both obese and non-obese subjects.

New perspectives on obesity-induced adipose tissue fibrosis and related clinical manifestations

Adipose tissue is a complex heterogeneous tissue composed of adipocytes along with several non-adipocyte populations, including blood, stromal, endothelial, and progenitor cells, as well as extracellular matrix (ECM) components. As obesity progresses, the adipose tissue expands dynamically through adipocyte hypertrophy and/or hyperplasia. This expansion requires continuous ECM remodeling to properly accommodate the size increase as well as functional changes. Upon reaching a hypertrophic threshold beyond the adipocyte buffering capacity, excess ECM components are deposited, causing fibrosis and ultimately resulting in unhealthy metabolic maladaptation. These complex ECM remodeling processes in adipose tissues are regulated by the local environment, several key mediators, and genetic factors that are closely linked to insulin sensitivity. It is crucial to understand how adipocytes interact with nonadipocyte populations and various mediators (i.e., immune cells, ECM components, and adipokines) during these processes. This mini-review provides an overview of the latest research into the biology of obesity-induced adipose tissue fibrosis and its related clinical manifestations, providing insight for further studies aimed at controlling metabolic syndrome and its comorbidities.

Role of adipose tissue macrophages in obesity-related disorders

The obesity epidemic has led researchers and clinicians to reconsider the etiology of this disease and precisely decipher its molecular mechanisms. The excessive accumulation of fat by cells, most notably adipocytes, which play a key role in this process, has many repercussions in tissue physiology. Herein, we focus on how macrophages, immune cells well known for their tissue gatekeeping functions, assume fundamental, yet ill-defined, roles in the genesis and development of obesity-related metabolic disorders. We first discuss the determinants of the biology of these cells before introducing the specifics of the adipose tissue environment, while highlighting its heterogeneity. Finally, we detail how obesity transforms both adipose tissue and local macrophage populations. Understanding macrophage diversity and their cross talk with the diverse cell types constituting the adipose tissue environment will allow us to frame the therapeutic potential of adipose tissue macrophages in obesity.