The Impact of Long-term Physical Inactivity on Adipose Tissue Immunometabolism.

CONTEXT: Adipose tissue and physical inactivity both influence metabolic health and systemic inflammation, but how adipose tissue responds to chronic physical inactivity is unknown. OBJECTIVE: This work aimed to characterize the impact of chronic physical inactivity on adipose tissue in healthy, young males. METHODS: We collected subcutaneous adipose tissue from 20 healthy, young men before and after 60 days of complete bed rest with energy intake reduced to maintain energy balance and fat mass. We used RNA sequencing, flow cytometry, ex vivo tissue culture, and targeted protein analyses to examine adipose tissue phenotype. RESULTS: Our results indicate that the adipose tissue transcriptome, stromal cellular compartment, and insulin signaling protein abundance are largely unaffected by bed rest when fat mass is kept stable. However, there was an increase in the circulating concentration of several adipokines, including plasma leptin, which was associated with inactivity-induced increases in plasma insulin and absent from adipose tissue cultured ex vivo under standardized culture conditions. CONCLUSION: Physical inactivity-induced disturbances to adipokine concentrations such as leptin, without changes to fat mass, could have profound metabolic implications outside a clinical facility when energy intake is not tightly controlled.

Increased Ratio of CD14++CD80+ Cells/CD14++CD163+ Cells in the Infrapatellar Fat Pad of End-Stage Arthropathy Patients.

Objectives: This study sought to identify the ratio of M1/M2 cells in the infrapatellar fat pads (IFP) and subcutaneous fat tissues (SC) of osteoarthritis (OA) and rheumatoid arthritis (RA) patients. The clinical features of OA and RA patients treated with or without biological disease-modifying anti-rheumatic drugs (bDMARDs) were also assessed. Methods: IFP and SC were collected from patients with OA and RA who are undergoing total knee arthroplasty (TKA). CD14-positive cells were then isolated from these samples. Flow cytometry was used to determine the number of CD14++CD80+ cells and CD14++CD163+ cells. The expression levels of lipid transcription factors, such as sterol regulatory element-binding protein 1 (SREBP1) and liver X receptor alpha (LXRA), and inflammatory cytokines were also evaluated. Results: Twenty OA patients and 22 RA patients were enrolled in this study. Ten of the RA patients (45.4%) received bDAMRDs before TKA. On average, a fivefold increase in the number of CD14-positive cells and lower expression levels of SREBP1C and LXRA were observed in OA IFP relative to OA SC; however, these results were not obtained from the RA samples. The median ratio of CD14++CD80+ cells/CD14++CD163+ cells of OA IFP was 0.87 (0.76-1.09, interquartile range), which is higher to that of OA SC with a lower ratio (p = 0.05835). Conclusions: The quantity and quality of CD14-positive cells differed between IFP and SC in arthropathy patients. To our knowledge, this is the first study to characterize the ratio of M1/M2 cells in the IFP and SC of end-stage OA and RA patients. The increased ratio of CD14++CD80+ cells/CD14++CD163+ cells in the IFP from patients with OA and RA treated with bDMARDs indicated that inflammation was localized in the IFP. As adipose tissue-derived innate immune cells were revealed as one of the targets for regulating inflammation, further analysis of these cells in the IFP may reveal new therapeutic strategies for inflammatory joint diseases.

CTRP-3 Regulates NOD1-mediated Inflammation and NOD1 Expression in Adipocytes and Adipose Tissue.

The anti-inflammatory adipokine CTRP-3 might affect innate immune reactions such as NOD1. The impact of CTRP-3 on NOD1-mediated inflammation in adipocytes and monocytic cells as well as on NOD1 expression was investigated. Murine 3T3-L1 pre-adipocytes and adipocytes as well as human THP-1 monocyte-like cells were co-stimulated with the synthetic NOD1 agonist Tri-DAP and recombinant CTRP-3. Gonadal adipose tissue and primary adipocytes were obtained from a murine model carrying a knockout (KO) of CTRP-3 in adipocytes but not in stroma-vascular cells. Wildtype mice with lipopolysaccharide (LPS)-induced elevated NOD1 expression were treated with CTRP-3. Secreted inflammatory cytokines in cell supernatants were measured by ELISA and mRNA levels were quantified by RT-PCR. Pro-inflammatory chemokine and cytokine secretion (MCP-1, RANTES, TNFα) was induced by NOD1 activation in adipocytes and monocyte-like cells, and MCP-1 and RANTES release was effectively inhibited by pre-incubation of cells with CTRP-3. CTRP-3 also antagonized LPS-triggered induction of NOD1 gene expression in murine adipose tissue, whereas adipocyte CTRP-3 deficiency upregulated NOD1 expression in adipose tissue. CTRP-3 is an effective antagonist of peptidoglycan-induced, NOD1-mediated inflammation and of LPS-induced NOD1 expression. Since basal NOD1 expression is increased by adipocyte CTRP-3 deficiency, there have to be also inflammation-independent mechanisms of NOD1 expression regulation by CTRP-3.

Obesity activates immunomodulating properties of mesenchymal stem cells in adipose tissue with differences between localizations.

Mesenchymal stem cells from healthy adipose tissue are adipocytes progenitors with immunosuppressive potential that are used for years in cell therapy. Whether adipose stem cells (ASC) may prevent inflammation in early obesity is not known. To address this question, we performed a kinetic study of high-fat (HF) diet induced obesity in mice to follow the immune regulating functions of adipose stem cells (ASC) isolated from the subcutaneous (SAT) and the visceral adipose tissue (VAT). Our results show that, early in obesity and before inflammation was detected, HF diet durably and differently activated ASC from SAT and VAT. Subcutaneous ASC from HF-fed mice strongly inhibited the proliferation of activated T lymphocytes, whereas visceral ASC selectively inhibited TNFα expression by macrophages and simultaneously released higher concentrations of IL6. These depot specific differences may contribute to the low-grade inflammation that develops with obesity in VAT while inflammation in SAT is delayed. The mechanisms involved differ from those already described for naïve cells activation with inflammatory cytokines and probably engaged metabolic activation. These results evidence that adipose stem cells are metabolic sensors acquiring an obesity-primed immunocompetent state in answer to depot-specific intrinsic features with overnutrition, placing these cells ahead of inflammation in the local dialog with immune cells.

Association between rs174537 FADS1 polymorphism and immune cell profiles in abdominal and femoral subcutaneous adipose tissue: an exploratory study in adults with obesity.

Fatty acid desaturase 1 (FADS1) polymorphisms alter fatty acid content in subcutaneous adipose tissue (SAT); however, existing evidence is limited and conflicting regarding the association between FADS1 variants and SAT inflammatory status. To advance this area, we conducted an exploratory study to investigate whether the common rs174537 polymorphism in FADS1 was associated with immune cell profiles in abdominal and femoral SAT in individuals with obesity. FADS1 gene expression and immune cell profiles in SAT depots were assessed by qPCR and flow cytometry, respectively. Although FADS1 gene expression was associated with genotype, no associations were observed with immune cell profiles in either depot. Our study provides additional evidence that rs174537 in FADS1 has minimal impact on inflammatory status in obese SAT.

[TGF-ß : A key player in age-related loss of skin innate immunity]. / TGF-ß : un acteur essentiel de la perte d'immunité innée du tissu cutané au cours du vieillissement - L'actualité scientifique vue par les étudiants du Master Biologie Santé, module physiopathologie de la signalisation, Université Paris-Saclay.

TITLE: TGF-ß : un acteur essentiel de la perte d'immunité innée du tissu cutané au cours du vieillissement - L'actualité scientifique vue par les étudiants du Master Biologie Santé, module physiopathologie de la signalisation, Université Paris-Saclay. ABSTRACT: Pour la sixième année, dans le cadre du module d'enseignement « Physiopathologie de la signalisation ¼ proposé par l'université Paris-sud, les étudiants du Master « Biologie Santé ¼ de l'université Paris-Saclay se sont confrontés à l'écriture scientifique. Ils ont sélectionné une quinzaine d'articles scientifiques récents dans le domaine de la signalisation cellulaire présentant des résultats originaux, via des approches expérimentales variées, sur des thèmes allant des relations hôte-pathogène aux innovations thérapeutiques, en passant par la signalisation hépatique et le métabolisme. Après un travail préparatoire réalisé avec l'équipe pédagogique, les étudiants, organisés en binômes, ont ensuite rédigé, guidés par des chercheurs, une Nouvelle soulignant les résultats majeurs et l'originalité de l'article étudié. Ils ont beaucoup apprécié cette initiation à l'écriture d'articles scientifiques et, comme vous pourrez le lire, se sont investis dans ce travail avec enthousiasme ! Trois de ces Nouvelles sont publiées dans ce numéro, les autres le seront dans des prochains numéros.

Fibroblast growth factor 2 exacerbates inflammation in adipocytes through NLRP3 inflammasome activation.

Chronic inflammation in adipose tissue is the hallmark of obesity and a major risk factor for the development of obesity-induced insulin resistance. NLRP3 inflammasome regulates the maturation and secretion of pro-inflammatory cytokines, such as IL-1ß and IL-18, and was recently discovered to be involved in obesity-related metabolic diseases. Fibroblast growth factors (FGFs) such as FGF1, FGF10, and FGF21 are adipokines that regulate adipocyte development and metabolism, but reports on the effect of other FGFs on adipocytes are lacking. In the present study, the novel role of FGF2 in NLRP3 inflammasome activation was elucidated. Our results showed that FGF2 levels were increased during adipocyte differentiation and in the adipose tissue of high-fat diet (HFD)-induced obese mice. Recombinant FGF2 treatment upregulated inflammasome markers such as NLRP3, which was further exaggerated by TNF-ɑ treatment. Interestingly, ß-Klotho, a co-receptor of FGF21, was significantly decreased by FGF2 treatment. Results from mice confirmed the positive correlation between FGF2 and NLRP3 expression in epididymal and subcutaneous adipose tissue, while exercise training effectively reversed HFD-induced NLRP3 expression as well as FGF2 levels in both adipose depots. Our results suggest that FGF2 is an adipokine that may exacerbate the inflammatory response in adipocytes through NLRP3 inflammasome activation.

Adoptive Cell Transfer of Regulatory T Cells Exacerbates Hepatic Steatosis in High-Fat High-Fructose Diet-Fed Mice.

Background and Aims: Non-alcoholic steatohepatitis (NASH) is a multisystem condition, involving the liver, adipose tissue, and immune system. Regulatory T (Treg) cells are a subset of T cells that exert an immune-controlling effect. Previously, a reduction of Treg cells in the visceral adipose tissue (VAT) was shown to be associated with a more severe degree of liver disease. We aimed to correct this immune disruption through adoptive cell transfer (ACT) of Treg cells. Methods: Male 8-week-old C57BL/6J mice were fed a high-fat high-fructose diet (HFHFD) for 20 weeks. Treg cells were isolated from the spleens of healthy 8 to 10-week-old C57BL/6J mice and were adoptively transferred to HFHFD-fed mice. PBS-injected mice served as controls. Plasma ALT and lipid levels were determined. Liver and adipose tissue were assessed histologically. Cytotoxic T (Tc), Treg, T helper (Th) 1 and Th17 cells were characterized in VAT, liver, subcutaneous adipose tissue (SAT), blood, and spleen via flow cytometry. Gene expression analysis was performed in SAT and VAT of mice fed either the HFHFD or a control diet for 10-32 weeks. Results: ACT increased Treg cells in SAT, but not in any of the other tissues. Moreover, the ACT induced a decrease in Th1 cells in SAT, liver, blood, and spleen. Higher plasma ALT levels and a higher degree of steatosis were observed in ACT mice, whereas the other HFHFD-induced metabolic and histologic disruptions were unaffected. Expression analysis of genes related to Treg-cell proliferation revealed a HFHFD-induced decrease in all investigated genes in the SAT, while in the VAT the expression of these genes was largely unaffected, except for a decrease in Pparg. Conclusion: ACT of Treg cells in HFHFD-fed mice exacerbated hepatic steatosis, which was possibly related to the increase of Treg cells in the SAT and/or the general decrease in Th1 cells. Moreover, the HFHFD-induced decrease in Pparg expression appeared critical in the decrease of Treg cells at the level of the VAT and the inability to replenish the amount of Treg cells by the ACT, while the mechanism of Treg cell accumulation at the level of the SAT remained unclear.

Association between Subcutaneous Adipose Tissue Inflammation, Insulin Resistance, and Calorie Restriction in Obese Females.

The worldwide epidemic of overweight and obesity has led to an increase in associated metabolic comorbidities. Obesity induces chronic low-grade inflammation in white adipose tissue (WAT). However, the function and regulation of both innate and adaptive immune cells in human WAT under conditions of obesity and calorie restriction (CR) is not fully understood yet. Using a randomized interventional design, we investigated postmenopausal overweight or obese female subjects who either underwent CR for 3 mo followed by a 4-wk phase of weight maintenance or had to maintain a stable weight over the whole study period. A comprehensive immune phenotyping protocol was conducted using validated multiparameter flow cytometry analysis in blood and s.c. WAT (SAT). The TCR repertoire was analyzed by next-generation sequencing and cytokine levels were determined in SAT. Metabolic parameters were determined by hyperinsulinemic-euglycemic clamp. We found that insulin resistance correlates significantly with a shift toward the memory T cell compartment in SAT. TCR analysis revealed a diverse repertoire in SAT of overweight or obese individuals. Additionally, whereas weight loss improved systemic insulin sensitivity in the intervention group, SAT displayed no significant improvement of inflammatory parameters (cytokine levels and leukocyte subpopulations) compared with the control group. Our data demonstrate the accumulation of effector memory T cells in obese SAT and an association between systemic glucose homeostasis and inflammatory parameters in obese females. The long-standing effect of obesity-induced changes in SAT was demonstrated by preserved immune cell composition after short-term CR-induced weight loss.

Regulatory T cells promote adipocyte beiging in subcutaneous adipose tissue.

Regulatory T cells (Tregs) play essential roles in obesity and diabetes. Here, we report a role of Tregs in enhancing ß3-adrenergic receptor agonist CL316243 (CL)-stimulated thermogenic program in subcutaneous adipose tissue (SAT), but not in visceral fat. CL treatment for 7 days increased SAT adipocyte beiging and thermogenic gene expression in male or female mice. Adoptive transfer of Tregs enhanced this CL activity. Such Treg activity lost in male epididymal white adipose tissue (eWAT) and female gonadal gWAT. Adipocyte culture yielded the same conclusion. Tregs enhanced the expression of CL-induced thermogenic genes in SAT from male and female mice. This activity of Tregs reduced or disappeared in adipocytes from eWAT or gWAT. Both CL and Tregs induced much higher UCP-1 (uncoupling protein-1) expression in SAT from females than that from males. A mechanistic study demonstrated a role of Tregs in suppressing the expression of M1 macrophage markers (Tnfa, Il6, iNos, Ip10) and promoting the expression of M2 macrophage markers (Mrc1, Arg1, Il10) in bone-marrow-derived macrophages or in SAT from male or female mice. In female mice with pre-established obesity, Treg adoptive transfer reduced the gWAT weight in 2 weeks. Together with CL treatment, Treg adoptive transfer reduced the SAT weight and further improved CL-induced glucose metabolism and insulin sensitivity in female obese mice, but did not affect CL-induced body weight loss in male or female obese mice. This study revealed a predominant role of Tregs in female mice in promoting adipocyte beiging and thermogenesis in SAT, in part by slanting M2 macrophage polarization.

Effect of the anti-retroviral drug, rilpivirine, on human subcutaneous adipose cells and its nutritional management using quercetin.

Rilpivirine, a recently developed drug of choice for initial treatment of HIV-1 infection, can greatly reduce HIV-related inflammation, but in turn, may be associated with adverse secondary effects, including disturbances in lipid metabolism and ultimately in adipose tissue distribution and function. In recent years, research findings on the benefits of anti-oxidant foods and supplements have been employed in counter-acting both oxidative stress as well as inflammation in order to reduce the adverse side effects of anti-retroviral therapy. One such natural flavonoid which possesses anti-inflammatory and anti-oxidative properties is quercetin. This study investigated the effect of quercetin in overcoming the side effects incurred due to rilpivirine administration. The results show substantial reduction in the accumulation of triglyceride levels in a dose- and time-dependent manner for adipose cells treated with either rilpivirine or quercetin alone and in combination, as evidenced by morphological pictures and quantitative measurement of triglycerides throughout the differentiation process. Levels of inflammatory markers such as resistin and IL-8 were increased as compared to the untreated cells. No significant changes in leptin were observed on treatment of adipose cells with rilpivirine alone and its levels were almost comparable to control. Levels of oxidative markers like superoxide dismutase, catalase, and glutathione were also decreased. Treatment with quercetin showed a decrease in the inflammatory status and an increase in the oxidative status of adipose cells, thereby exhibiting its anti-inflammatory and anti-oxidative properties. However, further assessment of lipid metabolism and adipose tissue function in patients administered with rilpivirine-based regimes is advisable considering that totally neutral effects of rilpivirine on lipid homeostasis cannot be anticipated from the current study in vitro. It is concluded that rilpivirine causes an anti-adipogenic and pro-inflammatory response pattern but only at high concentrations, whereas quercetin has been observed to decrease inflammation and restore the levels of anti-oxidant enzymes.

The fatty acid profile of adipose tissue as a predictor of the ponderal and inflammatory response in adult women six years after bariatric surgery.

BACKGROUND: Adipose tissue is involved in several metabolic changes. This study investigated the association between the fatty acid (FA) composition of subcutaneous (SAT) and visceral (VAT) adipose tissue pre-surgery and the postsurgical response regarding the evolution of weight and concentrations of tumour necrosis factor alpha (TNF) and interleukin 6 (IL-6) in adult women who underwent Roux-en-Y gastric bypass (RYGB, n = 14) or sleeve gastrectomy (SG, n = 19) at one (T1), three (T3) and six (T6) years after surgery. METHODS: Blood samples were collected to obtain plasma for the measurement of IL-6 and TNF. Anthropometric measurements were performed, collecting samples of VAT and SAT during surgery to assess the FA profiles. RESULTS: Weight loss had a positive correlation with the percentage of VAT-C17:0 (T1, T3) and SAT-C18:2 (T1, T3, T6), and it had a negative correlation with SAT-C22:0 (T1, T3) and VAT-C22:0 (T3). Regarding the inflammatory response, SAT-C14:0 (T6), VAT-C14:0 (T6), SAT-C14:1 (baseline), SAT-C15:0 (T6), SAT-C16:1 (T6), VAT-C16:1 (baseline), SAT-C17:1 (T6), VAT-C17:1 (baseline), VAT-C18:1 (T6), and VAT-C20:1 (T6) exhibited positive correlations with the concentration of IL-6, which were different from the correlations of IL-6 concentrations with SAT-C18:2, VAT-C18:2 (T6), and VAT-C18:3 (T6). The FA SAT-C18:0 (T1) was negatively correlated with TNF concentrations. CONCLUSIONS: Saturated FAs were predominantly proinflammatory, primarily in the late postoperative period. Alternately, the polyunsaturated FAs exhibited anti-inflammatory potential and predicted weight loss. Thus, the FA profile of the adipose tissue of obese adult women may be a predictor of the ponderal and inflammatory response 6 years after bariatric surgery. TRIAL REGISTRATION: This study was approved by the ethics committee of Federal University of Viçosa; Registration n. 17287913.2.0000.5153; Date: 07/05/2013.

Macrophages of the subcutaneous and omental fatty tissue in obese patients: Immunohistochemical phenotyping of M2 subtypes in relation to type 2 diabetes.

BACKGROUND AND AIMS: Macrophages are linked to the initiation of the chronic inflammation believed to underlie the changes taking place in the white fatty tissue of obese people. Both the number of macrophages, but their functional status, play an important role in the development of inflammation. Classically, macrophages are divided into two types: pro-inflammatory (M1) and anti-inflammatory (M2) types, and based on current immunological studies, further views on the functional distribution of macrophages are suggested. In this study, we evaluated the M1 and M2 macrophages ratio in obese subjects with, or without diabetes. To identify all macrophages, we used CD68 expression, while CD204 expression is typically used for the M2 macrophage. MATERIALS AND METHODS: During bariatric surgery, carried out in obese people with and without type 2 diabetes (T2D), we obtained subcutaneous adipose tissue from the navel and omental adipose tissue. We also obtained the same tissue from people with a physiological range of BMI from a judicial autopsy. Applying immunohistochemical staining anti-CD68 and anti-CD204, we carried out a quantitative evaluation of the number of macrophages. RESULTS: We found CD68+ and CD204+ positive macrophages in perivascular spaces and between fat cells, both isolated and in larger infiltrates. They were also present in so-called "crown-like structures" (CLS) around dying adipocytes. Quantitative analysis showed an increased number of macrophages in all obese patients compared to the control group of non-obese, individuals without T2D. The most striking observation was the macrophage increase in the visceral fatty tissue of diabetics. The number of CD68 and CD204 positive macrophages was statistically significantly smaller in patients without T2D. CONCLUSION: We demonstrated a significantly greater number of macrophages in visceral adipose tissue, especially in patients with T2D. Our results also show a positive correlation between the presence of T2D and the total number of macrophages; a significantly greater number of macrophages were found in visceral adipose tissue, especially in patients with T2D.

Immunophenotyping of Human B Lymphocytes in Blood and in Adipose Tissue.

The human obese subcutaneous adipose tissue (SAT) contributes to systemic and B cell intrinsic inflammation, reduced B cell responses, and increased secretion of autoimmune antibodies. Immune cells are recruited to the SAT by chemokines released by both adipocytes and infiltrating immune cells. We describe here the characterization of B lymphocytes from the SAT and blood (control) of obese females undergoing weight reduction surgeries (breast reduction or panniculectomy). We show how to isolate the immune cells from the blood and SAT, how to characterize B cells and their subsets, and how to measure markers of activation and/or transcription factors in SAT-derived B cells and B cell subsets. We also show how to evaluate other immune cell types infiltrating the SAT, including T cells, NK cells, monocyte/macrophages, in order to measure relative proportions of these cell types as compared to the blood.

Coronary disease is not associated with robust alterations in inflammatory gene expression in human epicardial fat.

Epicardial adipose tissue (EAT) is the visceral fat depot of the heart. Inflammation of EAT is thought to contribute to coronary artery disease (CAD). Therefore, we hypothesized that the EAT of patients with CAD would have increased inflammatory gene expression compared with controls without CAD. Cardiac surgery patients with (n = 13) or without CAD (n = 13) were consented, and samples of EAT and subcutaneous adipose tissue (SAT) were obtained. Transcriptomic analysis was performed using Affymetrix Human Gene 1.0 ST arrays. Differential expression was defined as a 1.5-fold change (ANOVA P < 0.05). Six hundred ninety-three genes were differentially expressed between SAT and EAT in controls and 805 in cases. Expression of 326 genes was different between EAT of cases and controls; expression of 14 genes was increased in cases, while 312 were increased in controls. Quantitative reverse transcription PCR confirmed that there was no difference in expression of CCL2, CCR2, TNF-α, IL-6, IL-8, and PAI1 between groups. Immunohistochemistry showed more macrophages in EAT than SAT, but there was no difference in their number or activation state between groups. In contrast to prior studies, we did not find increased inflammatory gene expression in the EAT of patients with CAD. We conclude that the specific adipose tissue depot, rather than CAD status, is responsible for the majority of differential gene expression.

Propionic acid counteracts the inflammation of human subcutaneous adipose tissue: a new avenue for drug development.

Adipose tissue is a primary site of obesity-induced inflammation, which has been emerging as an important contributor to obesity associated disorders. The factors influencing adipose tissue-induced inflammation and the resulting pathophysiological events remain poorly understood. However, dietary fiber consumptions appear to be protective. Short-chain fatty acids such as propionic acid (PA) are the principal products of the dietary fiber fermentation by microbiota. Therefore, we aim to investigate the influence of PA on inflammation, lipogenesis and glucose uptake markers from human subcutaneous adipose tissue (SAT). We showed that the treatment of SAT with PA resulted in a significant downregulation of inflammatory parameters (e.g. TNF-α and IP-10) and macrophage markers (e.g. CD163 and MMP-9). The expression levels of PA receptors (i.e. G protein coupled receptor-41 and -43) in human primary adipocytes were very low in comparison with SAT and macrophages. Upon PA treatment, no anti-inflammatory effect was observed in human adipocytes. PA significantly upregulated the expression of lipoprotein lipase (LPL), sterol regulatory-element-binding protein-1c (SREBP-1c) and glucose transporter 4 (GLUT-4), which are associated with lipogenesis and glucose uptake. We also showed that the observed anti-inflammatory effects of PA on SAT were partly mediated by Gi/o protein coupled receptor. Our data suggests that PA anti-inflammatory effects on SAT are mediated partly via Gi/o proteins, leading to the improved expression of factors associated with lipogenesis and glucose uptake. These responses appeared to be not mediated by adipocytes; but most probably by macrophages. The current study provides new knowledge, which can be used as a potential new avenue for drug development in preventing obesity-related inflammation and metabolic disorders in future. Graphical abstract Schematic presentation of study flow and the components of the investigation. In this study the effect of propionic acid (PA) on inflammation investigated in human subcutaneous adipose tissue (SAT), human primary adipocytes and the expression of a few hallmark inflammatory components produced by SAT and human adipocytes.

Immunopathogenesis of Juvenile Systemic Sclerosis.

Juvenile-onset systemic sclerosis (jSSc) is a rare and severe autoimmune disease with associated life-threatening organ inflammation and evidence of fibrosis. The organ manifestations of jSSc resemble adult SSc, but with better outcomes and survival. The etiology of jSSc appears to reflect adult-onset SSc, with similar inflammatory mediators and autoantibodies, but with a significant population of children with uncharacterized anti-nuclear antibodies. The genetics of patients with jSSc differ from women with SSc, resembling instead the genes of adult males with SSc, with additional HLA genes uniquely associated with childhood-onset disease. Current treatments are aimed at inhibiting the inflammatory aspect of disease, but important mechanisms of fibrosis regulated by dermal white adipose tissue dendritic cells may provide an avenue for targeting and potentially reversing the fibrotic stage.

The number and phenotype of myocardial and adipose tissue CD68+ cells is associated with cardiovascular and metabolic disease in heart surgery patients.

BACKGROUND AND AIMS: CD68+ cells are a potent source of inflammatory cytokines in adipose tissue and myocardium. The development of low-grade inflammation in adipose tissue is implicated in the pathogenesis of obesity-associated disorders including type 2 diabetes mellitus (T2DM) and cardiovascular disease. The main aim of the study was to characterize and quantify myocardial and adipose tissue CD68+ cells and adipose tissue crown-like structures (CLS) in patients with obesity, coronary artery disease (CAD) and T2DM. METHODS AND RESULTS: Samples were obtained from the right atrium, epicardial (EAT) and subcutaneous adipose tissue (SAT) during elective heart surgery (non-obese, n = 34 patients; obese, n = 24 patients). Immunohistochemistry was used to visualize CD68+ cells. M1-polarized macrophages were visualized by immunohistochemical detection of CD11c. The proportion of CD68+ cells was higher in EAT than in SAT (43.4 ± 25.0 versus 32.5 ± 23.1 cells per 1 mm2; p = 0.015). Myocardial CD68+ cells were more abundant in obese patients (45.6 ± 24.5 versus 27.7 ± 14.8 cells per 1 mm2; p = 0.045). In SAT, CD68+ cells were more frequent in CAD patients (37.3 ± 23.0 versus 23.1 ± 20.9 cells per 1 mm2; p = 0.012). Patients having CLS in their SAT had higher average BMI (34.1 ± 6.4 versus 29.0 ± 4.5; p = 0.024). CONCLUSIONS: Regional-based increases in the frequency of CD68+ cells and changes of their phenotype in CLS were detected in obese patients and CAD patients. Therapeutic modulation of adipose tissue inflammation may represent a target for treatment of obesity.