Senescence-associated ß-galactosidase in subcutaneous adipose tissue associates with altered glycaemic status and truncal fat in severe obesity.

AIM/HYPOTHESIS: Altered adipose tissue secretory profile contributes to insulin resistance and type 2 diabetes in obesity. Preclinical studies have identified senescent cells as a cellular source of proinflammatory factors in adipose tissue of obese mice. In humans, potential links with obesity comorbidities are poorly defined. Here, we investigated adipose tissue senescent status and relationships with metabolic complications in human obesity. METHODS: The study includes a prospective cohort of 227 individuals with severe obesity. A photometric method was used to quantify senescence-associated ß-galactosidase (SA-ß-gal) activity in paired subcutaneous and omental adipose tissue biopsies obtained during gastric surgery. Gene and secretory profiling was performed in adipose tissue biopsies and in human primary pre-adipocytes in the presence or absence of senolytic drugs targeting senescent cells. Participants were phenotyped for anthropometric and bioclinical variables, metabolic complications and gastric surgery-induced improvement to address relationships with adipose tissue SA-ß-gal. RESULTS: SA-ß-gal activity was sevenfold higher in subcutaneous than in omental adipose tissue and not associated with BMI or chronological age. Several factors, including insulin-like growth factor binding protein 3 (IGFBP3), plasminogen activator inhibitor 1 (PAI1), C-C motif chemokine ligand 2 (CCL2) and IL-6, were upregulated in subcutaneous adipose tissue in relation with SA-ß-gal (p for linear trend across tertiles <0.05) and in pre-adipocytes cultured with inflammatory macrophage conditioned media. Senolytic treatment reduced SA-ß-gal staining and normalised these alterations. In the whole population, subcutaneous adipose tissue SA-ß-gal activity was positively associated with serum leptin, markers of insulin resistance and increased trunk fat mass. Metabolic complications, including type 2 diabetes and dyslipidaemia, were more prevalent in patients with high levels of SA-ß-gal, but improved with bariatric surgery whatever the initial adipose tissue senescent status. CONCLUSIONS/INTERPRETATION: This study highlights a phenotype of senescence in adipose tissue of severely obese individuals, which characterises prominently subcutaneous fat depots. Subcutaneous adipose tissue senescence is significantly linked to altered glucose metabolism and body fat distribution. Elimination of senescent cells through senolytic treatment could alleviate metabolic complications in severely obese people. Graphical abstract.

Thymic stromal lymphopoietin links keratinocytes and dendritic cell-derived IL-23 in patients with psoriasis.

BACKGROUND: Thymic stromal lymphopoietin (TSLP) is a major proallergic cytokine that promotes TH2 responses through dendritic cell (DC) activation. Whether it also plays a role in human autoimmune inflammation and associated pathways is not known. OBJECTIVE: In this study we investigated the potential role of several epithelium-derived factors, including TSLP, in inducing IL-23 production by human DCs. We further dissected the role of TSLP in patients with psoriasis, an IL-23-associated skin autoimmune disease. METHODS: The study was performed in human subjects using primary cells and tissue samples from patients with psoriasis and healthy donors. We analyzed the production of IL-23 in vitro by blood and skin DCs. We studied the function for TSLP and its interaction with other components of the inflammatory microenvironment in situ and ex vivo. RESULTS: We found that TSLP synergized with CD40 ligand to promote DC activation and pathogenic IL-23 production by primary blood and skin DCs. In situ TSLP was strongly expressed by keratinocytes of untreated psoriatic lesions but not in normal skin. Moreover, we could demonstrate that IL-4, an important component of the TH2 inflammation seen in patients with atopic dermatitis, inhibited IL-23 production induced by TSLP and CD40 ligand in a signal transducer and activator of transcription 6-independent manner. CONCLUSION: Our results identify TSLP as a novel player within the complex psoriasis cytokine network. Blocking TSLP in patients with psoriasis might contribute to decreasing DC activation and shutting down the production of pathogenic IL-23.

Multiple-checkpoint inhibition of thymic stromal lymphopoietin-induced TH2 response by TH17-related cytokines.

BACKGROUND: The interplay between allergy and autoimmunity has been a matter of long debate. Epidemiologic studies point to a decreased frequency of allergy in patients with autoimmune diseases. However, recent studies suggest that IL-17 and related cytokines, which play a central role in autoimmunity, might also promote allergy. OBJECTIVE: To address this controversy, we systematically studied the interactions between T(H)17-related cytokines and the thymic stromal lymphopoietin (TSLP)-mediated proallergic pathway. METHODS: We used human primary dendritic cells (DCs), T cells, and skin explants. A novel geometric representation and multivariate ANOVA were used to analyze the T(H) cytokine profile. RESULTS: We show that IL-17A specifically inhibits TSLP production but increases proinflammatory IL-8 production in human skin explants exposed to TNF-α and IL-4. This inhibitory activity was confirmed in cultured skin explants of atopic dermatitis lesions. At the T-cell level, T(H)17-polarizing cytokines (IL-1ß, IL-6, TGF-ß, and IL-23) inhibited T(H)2 differentiation induced by TSLP-activated DCs. This led to a global dominance of a T(H)17-polarizing environment over TSLP-activated DCs, as revealed by clustering and computational analysis. CONCLUSIONS: Our data indicate that T(H)17-related cytokines are negative regulators of the TSLP immune pathway. This might explain the decreased frequency of allergy in patients with autoimmunity and suggests new means of manipulating proallergic responses.

Breast Reconstruction by Exclusive Lipofilling after Total Mastectomy for Breast Cancer: Description of the Technique and Evaluation of Quality of Life.

BACKGROUND: The objective of this work was to describe the technique of exclusive lipofilling in breast reconstruction after total mastectomy, to evaluate the satisfaction and quality of life of the patients, and to explore current literature on the subject. METHODS: We conducted a retrospective observational multicentric study from January 2013 to April 2020. The modalities of surgery, esthetic result, and patient satisfaction were evaluated with the breast reconstruction module of BREAST-Q. RESULTS: Complete data were available for 37 patients. The mean number of sessions was 2.2 (standard deviation 1.1), spread over an average of 6.8 months (SD 6.9). The average total volume of fat transferred was 566.4 mL. The complication rate was 18.9%. No severe complication was observed (Clavien-Dindo 3/4). Two patients were diagnosed with recurrence, in a metastatic mode (5.4%). The average satisfaction rate was 68.4% (SD 24.8) for psychosocial well-being and 64.5% (SD 24.1) for sexual well-being. The satisfaction rate was 60.2% (SD 20.9) for the image of the reconstructed breast and 82.7% (SD 21.9) for locoregional comfort. CONCLUSIONS: Breast reconstruction by exclusive lipofilling after total mastectomy provides satisfactory quality of life scores. The simplicity of the surgical technique and equipment required, and the high satisfaction rate confirm that lipofilling should be included in the panel of choice of breast reconstruction techniques.

Immune cell-derived cytokines contribute to obesity-related inflammation, fibrogenesis and metabolic deregulation in human adipose tissue.

Adipose tissue contains a variety of immune cells, which vary in abundance and phenotype with obesity. The contribution of immune cell-derived factors to inflammatory, fibrotic and metabolic alterations in adipose tissue is not well established in human obesity. Human primary adipose tissue cells, including pre-adipocytes, endothelial cells and mature adipocytes, were used to investigate deregulation of cell- and pathway-specific gene profiles. Among factors known to alter adipose tissue biology, we focus on inflammatory (IL-1ß and IL-17) and pro-fibrotic (TGF-ß1) factors. rIL-1ß and rIL-17 induced concordant pro-inflammatory transcriptional programs in pre-adipocytes and endothelial cells, with a markedly more potent effect of IL-1ß than IL-17. None of these cytokines had significant effect on fibrogenesis-related gene expression, contrasting with rTGF-ß1-induced up-regulation of extracellular matrix components and pro-fibrotic factors. In mature adipocytes, all three factors promoted down-regulation of genes functionally involved in lipid storage and release. IL-1ß and IL-17 impacted adipocyte metabolic genes in relation with their respective pro-inflammatory capacity, while the effect of TGF-ß1 occurred in face of an anti-inflammatory signature. These data revealed that IL-1ß and IL-17 had virtually no effect on pro-fibrotic alterations but promote inflammation and metabolic dysfunction in human adipose tissue, with a prominent role for IL-1ß.

A PDGFRα-Mediated Switch toward CD9high Adipocyte Progenitors Controls Obesity-Induced Adipose Tissue Fibrosis.

Obesity-induced white adipose tissue (WAT) fibrosis is believed to accelerate WAT dysfunction. However, the cellular origin of WAT fibrosis remains unclear. Here, we show that adipocyte platelet-derived growth factor receptor-α-positive (PDGFRα+) progenitors adopt a fibrogenic phenotype in obese mice prone to visceral WAT fibrosis. More specifically, a subset of PDGFRα+ cells with high CD9 expression (CD9high) originates pro-fibrotic cells whereas their CD9low counterparts, committed to adipogenesis, are almost completely lost in the fibrotic WAT. PDGFRα pathway activation promotes a phenotypic shift toward PDGFRα+CD9high fibrogenic cells, driving pathological remodeling and altering WAT function in obesity. These findings translated to human obesity as the frequency of CD9high progenitors in omental WAT (oWAT) correlates with oWAT fibrosis level, insulin-resistance severity, and type 2 diabetes. Collectively, our data demonstrate that in addition to representing a WAT adipogenic niche, different PDGFRα+ cell subsets modulate obesity-induced WAT fibrogenesis and are associated with loss of metabolic fitness.

Increased Basement Membrane Components in Adipose Tissue During Obesity: Links With TGFß and Metabolic Phenotypes.

CONTEXT: Collagen accumulation around adipocytes and vessels (ie, pericellular fibrosis) is a hallmark of obese adipose tissue associated with altered metabolism. OBJECTIVE: Our objective was to evaluate components of basement membrane (BM) in adipose tissue, including collagen IV, a major BM component, and its relationships with metabolic parameters and TGFß isoforms. DESIGN AND SETTING: We used immuno-techniques and gene expression approaches to detect BM components in subcutaneous and visceral adipose tissue samples. Adipocytes and endothelial cells were isolated from lean and obese adipose tissue. We also focused on the expression of COL4A1 correlated to metabolic variables in moderate obesity and, in severe obesity before and after bariatric surgery. Using in vitro analysis, we explored the impact of TGFß isoforms on the expression of inflammatory and extracellular matrix genes in adipocytes and endothelial cells. RESULTS: BM components were detected around adipocytes and endothelial cells, and were increased in obese adipocytes. COL4A1 expression was positively correlated with insulin-resistance indices in obese subjects and showed less reduction in severely obese subjects with poorer insulin-resistance outcomes 6 months after gastric bypass. COL4A1 expression also correlated with TGFß1 and TGFß3 gene expressions in subcutaneous adipose tissue. Stimulating isolated adipocytes and endothelial cells in vitro with these TGFß isoforms showed an inflammatory and pro-fibrotic phenotype. However, TGFß1 and TGFß3 exposure only provoked COL4A1 overexpression in endothelial cells and not in adipocytes. CONCLUSION: The disorganization of several BM components, including collagen IV, could contribute to pathological alterations of obese adipose tissue and cells.

Cutting Edge: Proinflammatory and Th2 cytokines synergize to induce thymic stromal lymphopoietin production by human skin keratinocytes.

Thymic stromal lymphopoietin (TSLP) is an epithelial cell-derived cytokine that strongly activates dendritic cells (DC) and can initiate allergic inflammation. The factors inducing the production of human TSLP are not known. In this study, we show that proinflammatory (TNF-alpha or IL-1alpha) and Th2 (IL-4 or IL-13) cytokines synergized to induce the production of TSLP in human skin explants. TSLP production in situ was restricted to epidermal keratinocytes of the suprabasal layer. TSLP production could not be inhibited by factors regulating Th2 inflammation, such as IL-10, TGF-beta, or IFN-gamma. Cytokine-treated skin culture supernatants induced the maturation of blood CD11c(+) DC in a TSLP-dependent manner. Our data provide the first evidence of TSLP induction and subsequent DC activation in human skin. Blocking TSLP-inducing cytokines could represent a novel strategy for the treatment of allergic diseases.

[Local recurrence after breast conserving treatment: place of surgery]. / Récidives locales après traitement conservateur des cancers du sein: place de la chirurgie.

Since the end of the sixties, conservative radiosurgical treatment is the standard for unifocal breast cancers < 3 cm. Retrospective and randomised trials confirmed identical survival, but an increased second failure's rate. Impact of this local failure on survival is controversy. Different prognostic factors were identified by the authors. Local extension of the local failure and inflammatory signs, the delay of its apparition and its site (witch could difference true local failure and new tumour) the histologic type of the local failure, the phase S cells rate, the N status, and characteristics of the initial tumour such as the N status, the tumour's size. The surgical treatment of the local failure is classically the salvage mastectomy associated with immediate breast reconstruction, often by cutaneous-muscular flaps. A second conservative treatment could eventually be proposed only if breast size and radiotherapy sequels would permit a second carcinologic and cosmetic surgical treatment: wide local excision and re-irradiation, unifocal tumour < 1 cm preferentially intraductal, well differentiated without lymphovascular embole, without extensive intraductal, second new cancer (in other quadrant than the initial tumor after a long enough delay), efficient and long time survey. RMN with identification of the prognostic criteria would contribute to identify the local failure witch could benefit of an iterative conservative treatment.