Marine-Derived Phosphoeleganin and Its Semisynthetic Derivative Decrease IL6 Levels and Improve Insulin Signaling in Human Hepatocellular Carcinoma Cells.

Marine natural products constitute a great source of potential new antidiabetic drugs. The aim of this study was to evaluate the role of phosphoeleganin (PE), a polyketide purified from the Mediterranean ascidian Sidnyum elegans, and its derivatives PE/2 and PE/3 on insulin sensitivity in human hepatocellular carcinoma (HepG2) cells. In our experiments, insulin stimulates the phosphorylation of its receptor (INSR) and AKT by 1.5- and 3.5-fold, respectively, whereas in the presence of PE, PE/2, and PE/3, the insulin induced INSR phosphorylation is increased by 2.1-, 2-, and 1.5-fold and AKT phosphorylation by 7.1-, 6.0-, and 5.1-fold, respectively. Interestingly, PE and PE/2 have an additive effect on insulin-mediated reduction of phosphoenolpyruvate carboxykinase (PEPCK) expression. Finally, PE and PE/2, but not PE/3, decrease interleukin 6 (IL6) secretion and expression before and after palmitic acid incubation, while in the presence of high glucose (HG), only PE reduces IL6. Levels of other cytokines are not significantly affected by PE and its derivates. All these data suggest that PE and its synthetic-derived compound, PE/2, significantly decrease IL6 and improve hepatic insulin signaling. As IL6 impairs insulin action, it could be hypothesized that PE and PE/2, by inhibiting IL6, may improve the hepatic insulin pathway.

Semaphorin 3A Increases in the Plasma of Women with Diminished Ovarian Reserve Who Respond Better to Controlled Ovarian Stimulation.

Semaphorin 3A (SEMA3A) plays a crucial role in the development, differentiation, and plasticity of specific types of neurons that secrete Gonadotropin-Releasing Hormone (GnRH) and regulates the acquisition and maintenance of reproductive competence in humans and mice. Its insufficient expression has been linked to reproductive disorders in humans, which are characterized by reduced or failed sexual competence. Various mutations, polymorphisms, and alternatively spliced variants of SEMA3A have been associated with infertility. One of the common causes of infertility in women of reproductive age is diminished ovarian reserve (DOR), characterized by a reduced ovarian follicular pool. Despite its clinical significance, there are no universally accepted diagnostic criteria or therapeutic interventions for DOR. In this study, we analyzed the SEMA3A plasma levels in 77 women and investigated their potential role in influencing fertility in patients with DOR. The results revealed that the SEMA3A levels were significantly higher in patients with DOR than in healthy volunteers. Furthermore, the SEMA3A levels were increased in patients who underwent fertility treatment and had positive Beta-Human Chorionic Gonadotropin (ßHCG) values (ß+) after controlled ovarian stimulation (COS) compared to those who had negative ßHCG values (ß-). These findings may serve as the basis for future investigations into the diagnosis of infertility and emphasize new possibilities for the SEMA3A-related treatment of sexual hormonal dysfunction that leads to infertility.

Visceral Obesity and Cytokeratin-18 Antigens as Early Biomarkers of Liver Damage.

Visceral obesity is linked to the progression of fatty liver to nonalcoholic steatohepatitis (NASH). Cytokeratin-18 (CK18) epitopes M30 (CK18M30) and M65 (CK18M65) represent accurate markers for detecting NASH. The aim of this study was to evaluate the association of CK18M30 and CK18M65 levels with anthropometric and metabolic characteristics, liver stiffness, and liver indices of steatosis and fibrosis in a cohort of subjects with visceral obesity; in this cross-sectional study, transient elastography (TE-Fibroscan®), anthropometric measurements, metabolic parameters, High Sensitivity C-Reactive Protein (hsCRP), and CK18M30 and CK18M65 levels (Apoptosense ELISA, PEVIVA, Germany) were evaluated. Fatty Liver Index (FLI), Fibrosis 4 (FIB-4), and Aspartate transaminase (AST)-platelet ratio index (APRI) were calculated; among 48 subjects, 47.2% presented metabolic syndrome, 93.8% hepatic steatosis, 60.4% high liver stiffness, and 14.6% hypertransminasemia, while FIB-4 and APRI were normal. CK18M30 and CK18M65 levels were significantly correlated with waist circumference, AST, ALT, HoMA-IR, liver stiffness, and APRI (p < 0.001). Subjects with CK18 fragments above the median values showed significantly higher waist circumference, HbA1c, AST, ALT, HoMA-IR, FLI, and APRI compared to those with values below the median; CK18M30 and CK18M65 levels correlated well with anthropometric and metabolic characteristics, representing good biomarkers for early identification of NASH in subjects with visceral obesity.

SARS-CoV-2 Affects Both Humans and Animals: What Is the Potential Transmission Risk? A Literature Review.

In March 2020, the World Health Organization Department declared the coronavirus (COVID-19) outbreak a global pandemic, as a consequence of its rapid spread on all continents. The COVID-19 pandemic has been not only a health emergency but also a serious general problem as fear of contagion and severe restrictions put economic and social activity on hold in many countries. Considering the close link between human and animal health, COVID-19 might infect wild and companion animals, and spawn dangerous viral mutants that could jump back and pose an ulterior threat to us. The purpose of this review is to provide an overview of the pandemic, with a particular focus on the clinical manifestations in humans and animals, the different diagnosis methods, the potential transmission risks, and their potential direct impact on the human-animal relationship.

Lifestyle and Dietary Habits Affect Plasma Levels of Specific Cytokines in Healthy Subjects.

Low-grade chronic inflammation (LGCI) is a common feature of non-communicable diseases. Cytokines play a crucial role in LGCI. This study aimed to assess how LGCI risk factors [e.g., age, body mass index (BMI), smoke, physical activity, and diet] may impact on specific cytokine levels in a healthy population. In total, 150 healthy volunteers were recruited and subjected to questionnaires about the last 7-day lifestyle, including smoking habit, physical activity, and food frequency. A panel of circulating cytokines, chemokines, and growth factors was analyzed by multiplex ELISA. BMI showed the heaviest impact on the correlation between LGCI-related risk factors and cytokines and was significantly associated with CRP levels. Aging was characterized by an increase in IL-1b, eotaxin, MCP-1, and MIP-1α. Smoking was related to higher levels of IL-1b and CCL5/RANTES, while physical activity was related to MIP-1α. Within the different eating habits, CRP levels were modulated by eggs, red meat, shelled fruits, and greens consumption; however, these associations were not confirmed in a multivariate model after adjusting for BMI. Nevertheless, red meat consumption was associated with an inflammatory pattern, characterized by an increase in IL-6 and IL-8. IL-8 levels were also increased with the frequent intake of sweets, while a higher intake of shelled fruits correlated with lower levels of IL-6. Moreover, IL-6 and IL-8 formed a cluster that also included IL-1b and TNF-α. In conclusion, age, BMI, smoke, physical activity, and dietary habits are associated with specific cytokines that may represent potential markers for LGCI.

Correction: Bisphenol-A Impairs Insulin Action and Up-Regulates Inflammatory Pathways in Human Subcutaneous Adipocytes and 3T3-L1 Cells.

[This corrects the article DOI: 10.1371/journal.pone.0082099.].

Diabetes and Cognitive Impairment: A Role for Glucotoxicity and Dopaminergic Dysfunction.

Diabetes mellitus (DM) is a chronic metabolic disorder characterized by hyperglycemia, responsible for the onset of several long-term complications. Recent evidence suggests that cognitive dysfunction represents an emerging complication of DM, but the underlying molecular mechanisms are still obscure. Dopamine (DA), a neurotransmitter essentially known for its relevance in the regulation of behavior and movement, modulates cognitive function, too. Interestingly, alterations of the dopaminergic system have been observed in DM. This review aims to offer a comprehensive overview of the most relevant experimental results assessing DA's role in cognitive function, highlighting the presence of dopaminergic dysfunction in DM and supporting a role for glucotoxicity in DM-associated dopaminergic dysfunction and cognitive impairment. Several studies confirm a role for DA in cognition both in animal models and in humans. Similarly, significant alterations of the dopaminergic system have been observed in animal models of experimental diabetes and in diabetic patients, too. Evidence is accumulating that advanced glycation end products (AGEs) and their precursor methylglyoxal (MGO) are associated with cognitive impairment and alterations of the dopaminergic system. Further research is needed to clarify the molecular mechanisms linking DM-associated dopaminergic dysfunction and cognitive impairment and to assess the deleterious impact of glucotoxicity.

Functional brain network topology across the menstrual cycle is estradiol dependent and correlates with individual well-being.

The menstrual cycle (MC) is a sex hormone-related phenomenon that repeats itself cyclically during the woman's reproductive life. In this explorative study, we hypothesized that coordinated variations of multiple sex hormones may affect the large-scale organization of the brain functional network and that, in turn, such changes might have psychological correlates, even in the absence of overt clinical signs of anxiety and/or depression. To test our hypothesis, we investigated longitudinally, across the MC, the relationship between the sex hormones and both brain network and psychological changes. We enrolled 24 naturally cycling women and, at the early-follicular, peri-ovulatory, and mid-luteal phases of the MC, we performed: (a) sex hormone dosage, (b) magnetoencephalography recording to study the brain network topology, and (c) psychological questionnaires to quantify anxiety, depression, self-esteem, and well-being. We showed that during the peri-ovulatory phase, in the alpha band, the leaf fraction and the tree hierarchy of the brain network were reduced, while the betweenness centrality (BC) of the right posterior cingulate gyrus (rPCG) was increased. Furthermore, the increase in BC was predicted by estradiol levels. Moreover, during the luteal phase, the variation of estradiol correlated positively with the variations of both the topological change and environmental mastery dimension of the well-being test, which, in turn, was related to the increase in the BC of rPCG. Our results highlight the effects of sex hormones on the large-scale brain network organization as well as on their possible relationship with the psychological state across the MC. Moreover, the fact that physiological changes in the brain topology occur throughout the MC has widespread implications for neuroimaging studies.

In severe obesity, subcutaneous adipose tissue cell-derived cytokines are early markers of impaired glucose tolerance and are modulated by quercetin.

BACKGROUND: Excessive adiposity provides an inflammatory environment. However, in people with severe obesity, how systemic and local adipose tissue (AT)-derived cytokines contribute to worsening glucose tolerance is not clear. METHODS: Ninty-two severely obese (SO) individuals undergoing bariatric surgery were enrolled and subjected to detailed clinical phenotyping. Following an oral glucose tolerance test, participants were included in three groups, based on the presence of normal glucose tolerance (NGT), impaired glucose tolerance (IGT), or type 2 diabetes (T2D). Serum and subcutaneous AT (SAT) biopsies were obtained and mesenchymal stem cells (MSCs) were isolated, characterized, and differentiated in adipocytes in vitro. TNFA and PPARG mRNA levels were determined by qRT-PCR. Circulating, adipocyte- and MSC-released cytokines, chemokines, and growth factors were assessed by multiplex ELISA. RESULTS: Serum levels of IL-9, IL-13, and MIP-1ß were increased in SO individuals with T2D, as compared with those with either IGT or NGT. At variance, SAT samples obtained from SO individuals with IGT displayed levels of TNFA which were threefold higher compared to those with NGT, but not different from those with T2D. Elevated levels of TNFα were also found in differentiated adipocytes, isolated from the SAT specimens of individuals with IGT and T2D, compared to those with NGT. Consistent with the pro-inflammatory milieu, IL-1ß and IP-10 secretion was significantly higher in adipocytes from individuals with IGT and T2D. Moreover, increased levels of TNFα, both mRNA and secreted protein were detected in MSCs obtained from IGT and T2D, compared to NGT SO individuals. Exposure of T2D and IGT-derived MSCs to the anti-inflammatory flavonoid quercetin reduced TNFα levels and was paralleled by a significant decrease of the secretion of inflammatory cytokines. CONCLUSION: In severe obesity, enhanced SAT-derived inflammatory phenotype is an early step in the progression toward T2D and maybe, at least in part, attenuated by quercetin.

Surgical stress and metabolic response after totally laparoscopic right colectomy.

No clear consensus on the need to perform an intracorporeal anastomosis (IA) after laparoscopic right colectomy is currently available. One of the potential benefits of intracorporeal anastomosis may be a reduction in surgical stress. Herein, we evaluated the surgical stress response and the metabolic response in patients who underwent right colonic resection for colon cancer. Fifty-nine patients who underwent laparoscopic resection for right colon cancer were randomized to receive an intracorporeal or an extracorporeal anastomosis (EA). Data including demographics (age, sex, BMI and ASA score), pathological (AJCC tumour stage and tumour localization) and surgical results were recorded. Moreover, to determine the levels of the inflammatory response, mediators, such as C-reactive protein (CRP), tumour necrosis factor (TNF), interleukin 1ß (IL-1ß), IL-6, IL-10, and IL-13, were evaluated. Similarly, cortisol and insulin levels were evaluated as hormonal responses to surgical stress. We found that the proinflammatory mediator IL-6, CRP, TNF and IL-1ß levels, were significantly reduced in IA compared to EA. Concurrently, an improved profile of the anti-inflammatory cytokines IL-10 and IL-13 was observed in the IA group. Relative to the hormone response to surgical stress, cortisol was increased in patients who underwent EA, while insulin was reduced in the EA group. Based on these results, surgical stress and metabolic response to IA justify advocating the adoption of a totally laparoscopic approach when performing a right colectomy for cancer.This trial is registered on ClinicalTrials.gov (ID: NCT03422588).

Seroprevalence of SARS-CoV-2 Assessed by Four Chemiluminescence Immunoassays and One Immunocromatography Test for SARS-Cov-2.

The onset of the new SARS-CoV-2 coronavirus encouraged the development of new serologic tests that could be additional and complementary to real-time RT-PCR-based assays. In such a context, the study of performances of available tests is urgently needed, as their use has just been initiated for seroprevalence assessment. The aim of this study was to compare four chemiluminescence immunoassays and one immunochromatography test for SARS-Cov-2 antibodies for the evaluation of the degree of diffusion of SARS-CoV-2 infection in Salerno Province (Campania Region, Italy). A total of 3,185 specimens from citizens were tested for anti-SARS-CoV-2 antibodies as part of a screening program. Four automated immunoassays (Abbott and Liaison SARS-CoV-2 CLIA IgG and Roche and Siemens SARS-CoV-2 CLIA IgM/IgG/IgA assays) and one lateral flow immunoassay (LFIA Technogenetics IgG-IgM COVID-19) were used. Seroprevalence in the entire cohort was 2.41, 2.10, 1.82, and 1.85% according to the Liaison IgG, Abbott IgG, Siemens, and Roche total Ig tests, respectively. When we explored the agreement among the rapid tests and the serologic assays, we reported good agreement for Abbott, Siemens, and Roche (Cohen's Kappa coefficient 0.69, 0.67, and 0.67, respectively), whereas we found moderate agreement for Liaison (Cohen's kappa coefficient 0.58). Our study showed that Abbott and Liaison SARS-CoV-2 CLIA IgG, Roche and Siemens SARS-CoV-2 CLIA IgM/IgG/IgA assays, and LFIA Technogenetics IgG-IgM COVID-19 have good agreement in seroprevalence assessment. In addition, our findings indicate that the prevalence of IgG and total Ig antibodies against SARS-CoV-2 at the time of the study was as low as around 3%, likely explaining the amplitude of the current second wave.

Reproductive function of long-term treated patients with hepatic onset of Wilson's disease: a prospective study.

RESEARCH QUESTION: Wilson's disease (WD) is a disorder of copper metabolism that can cause hormonal alterations. The impact of WD and its therapies on fertility is not well defined. The aim of this study was to evaluate ovarian reserve and sperm parameters in long-term treated WD patients with hepatic onset. DESIGN: WD patients with hepatic onset treated for at least 5 years were compared with healthy controls. Men underwent spermiogram and sperm DNA fragmentation (SDF) analysis. Women were tested for serum FSH, anti-Müllerian hormone (AMH) and sonographic antral follicle count (AFC) in the early follicular phase. Ovulation was monitored with ultrasound and progesterone serum concentrations in the luteal phase. RESULTS: The WD group included 26 patients (12 males), the control group 19 subjects (9 males). All patients apart from four (one male) were responders to WD treatment. Sperm count and morphology were comparable between cases and controls. Sperm motility (total and after 1 h) was significantly lower in cases (44.78 ± 21.65%; 47.85 ± 21.52%) than controls (61.88 ± 11.03; 69.44 ± 11.02%, P = 0.03 and 0.01, respectively). The only non-responder had severe oligo-astheno-teratozoospermia. SDF values were normal in cases and controls. AMH, AFC and FSH did not differ between cases and controls. LH was significantly lower in cases (3.36 ± 1.65 mIU/ml) than controls (6.25 ± 1.03 mIU/ml, P < 0.0001). A non-responder woman who developed neurological signs had a 7-year history of infertility. CONCLUSIONS: WD patients with hepatic onset, diagnosed early and treated, have no impairment in fertility potential even if males show reduced sperm motility and females lower LH values. Only patients with poor disease control have some evidence of impaired fertility.

Potential Mechanisms of Bisphenol A (BPA) Contributing to Human Disease.

Bisphenol A (BPA) is an organic synthetic compound serving as a monomer to produce polycarbonate plastic, widely used in the packaging for food and drinks, medical devices, thermal paper, and dental materials. BPA can contaminate food, beverage, air, and soil. It accumulates in several human tissues and organs and is potentially harmful to human health through different molecular mechanisms. Due to its hormone-like properties, BPA may bind to estrogen receptors, thereby affecting both body weight and tumorigenesis. BPA may also affect metabolism and cancer progression, by interacting with GPR30, and may impair male reproductive function, by binding to androgen receptors. Several transcription factors, including PPARγ, C/EBP, Nrf2, HOX, and HAND2, are involved in BPA action on fat and liver homeostasis, the cardiovascular system, and cancer. Finally, epigenetic changes, such as DNA methylation, histones modification, and changes in microRNAs expression contribute to BPA pathological effects. This review aims to provide an extensive and comprehensive analysis of the most recent evidence about the potential mechanisms by which BPA affects human health.

Diagnosis of Flier's syndrome in a patient with nondiabetic hypoglycemia: a case report and critical appraisal of the literature.

PURPOSE: Autoimmune hypoglycemia includes rare syndromes characterized by the presence of either anti-insulin antibodies (IAA) (Hirata's disease) or anti-insulin receptor (anti-ISR) antibodies (Flier's syndrome). Diagnosis is usually based on identification of the specific antibodies, in presence of the Whipple triad. However, most of these cases are classified as idiopathic diseases due to the difficulty to define the pathogenic culprit. METHODS: Basic research methodologies, including Western Blot and ELISA tests, have been used in this study. RESULTS: We describe a 21-year-old young woman (PT), non-obese and non-diabetic, with a positive history of autoimmune diseases, admitted to the hospital for recurrent episodes of severe symptomatic hypoglycemia. Counterregulatory response to hypoglycemia was normal as well as the fasting test, so excluding both hormone deficiencies and insulinoma. Since an autoimmune hypoglycemic syndrome was suspected, the hyperactivation of the insulin pathway was experimentally evaluated. At this purpose, human hepatocarcinoma (HepG2) cells were incubated with serum obtained from the patient (PT) and from control individuals. Interestingly, a significant increase of phosphorylation of insulin receptor, Akt, and ERK1/2 was observed in the HepG2 cells incubated with PT serum compared with the controls. ELISA tests revealed significantly increased levels of anti-ISR antibodies in PT serum, while IAA were similar both in PT and in control sera, supporting diagnosis of Flier's syndrome. CONCLUSIONS: This study emphasizes the importance to identify new strategies for the differential diagnosis of hypoglycemia, not always possible with the routinely used diagnostic tests.

The Thyroid Hormone Inactivator Enzyme, Type 3 Deiodinase, Is Essential for Coordination of Keratinocyte Growth and Differentiation.

Background: Thyroid hormones (THs) are key regulators of development, tissue differentiation, and maintenance of metabolic balance in virtually every cell of the body. Accordingly, severe alteration of TH action during fetal life leads to permanent deficits in humans. The skin is among the few adult tissues expressing the oncofetal protein type 3 deiodinase (D3), the TH inactivating enzyme. Here, we demonstrate that D3 is dynamically regulated during epidermal ontogenesis. Methods: To investigate the function of D3 in a postdevelopmental context, we used a mouse model of conditional epidermal-specific D3 depletion. Loss of D3 resulted in tissue hypoplasia and enhanced epidermal differentiation in a cell-autonomous manner. Results: Accordingly, wound healing repair and hair follicle cycle were altered in the D3-depleted epidermis. Further, in vitro ablation of D3 in primary culture of keratinocytes indicated that various markers of stratified epithelial layers were upregulated, thereby confirming the pro-differentiative action of D3 depletion and the consequent increased intracellular triiodothyronine levels. Notably, loss of D3 reduced the clearance of systemic TH in vivo, thereby demonstrating the critical requirement for epidermal D3 in the maintenance of TH homeostasis. Conclusion: In conclusion, our results show that the D3 enzyme is a key TH-signaling component in the skin, thereby providing a striking example of a physiological context for deiodinase-mediated TH metabolism, as well as a rationale for therapeutic manipulation of deiodinases in pathophysiological contexts.

Prep1 regulates angiogenesis through a PGC-1α-mediated mechanism.

Angiogenesis depends on a delicate balance between the different transcription factors, and their control should be considered necessary for preventing or treating diseases. Pre-B-cell leukemia transcription factor regulating protein 1 (Prep1) is a homeodomain transcription factor that plays a primary role in organogenesis and metabolism. Observations performed in a Prep1 hypomorphic mouse model, expressing 3-5% of the protein, show an increase of embryonic lethality due, in part, to defects in angiogenesis. In this study, we provide evidence that overexpression of Prep1 in mouse aortic endothelial cells (MAECs) stimulates migration, proliferation, and tube formation. These effects are paralleled by an increase of several proangiogenic factors and by a decrease of the antiangiogenic gene neurogenic locus notch homolog protein 1 (Notch1). Prep1-mediated angiogenesis involves the activation of the p160 Myb-binding protein (p160)/peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) pathway. Indeed, Prep1 overexpression increases its binding with p160 and induces a 4-fold increase of p160 and 70% reduction of PGC-1α compared with control cells. Incubation of MAECs with a synthetic Prep1(54-72) peptide, mimicking the Prep1 region involved in the interaction with p160, reverts the proangiogenic effects mediated by Prep1. In addition, Prep1 levels increase by 3.2-fold during the fibroblast growth factor ß (bFGF)-mediated endothelial colony-forming cells' activation, whereas Prep1(54-72) peptide reduces the capability of these cells to generate tubular-like structures in response to bFGF, suggesting a possible role of Prep1 both in angiogenesis from preexisting vessels and in postnatal vasculogenesis. Finally, Prep1 hypomorphic heterozygous mice, expressing low levels of Prep1, show attenuated placental angiogenesis and vessel formation within Matrigel plugs. All of these observations indicate that Prep1, complexing with p160, decreases PGC-1α and stimulates angiogenesis.-Cimmino, I., Margheri, F., Prisco, F., Perruolo, G., D'Esposito, V., Laurenzana, A., Fibbi, G., Paciello, O., Doti, N., Ruvo, M., Miele, C., Beguinot, F., Formisano, P., Oriente, F. Prep1 regulates angiogenesis through a PGC-1α-mediated mechanism.

The Relevance of Insulin Action in the Dopaminergic System.

The advances in medicine, together with lifestyle modifications, led to a rising life expectancy. Unfortunately, however, aging is accompanied by an alarming boost of age-associated chronic pathologies, including neurodegenerative and metabolic diseases. Interestingly, a non-negligible interplay between alterations of glucose homeostasis and brain dysfunction has clearly emerged. In particular, epidemiological studies have pointed out a possible association between Type 2 Diabetes (T2D) and Parkinson's Disease (PD). Insulin resistance, one of the major hallmark for etiology of T2D, has a detrimental influence on PD, negatively affecting PD phenotype, accelerating its progression and worsening cognitive impairment. This review aims to provide an exhaustive analysis of the most recent evidences supporting the key role of insulin resistance in PD pathogenesis. It will focus on the relevance of insulin in the brain, working as pro-survival neurotrophic factor and as a master regulator of neuronal mitochondrial function and oxidative stress. Insulin action as a modulator of dopamine signaling and of alpha-synuclein degradation will be described in details, too. The intriguing idea that shared deregulated pathogenic pathways represent a link between PD and insulin resistance has clinical and therapeutic implications. Thus, ongoing studies about the promising healing potential of common antidiabetic drugs such as metformin, exenatide, DPP IV inhibitors, thiazolidinediones and bromocriptine, will be summarized and the rationale for their use to decelerate neurodegeneration will be critically assessed.

Correction to: Human heart shifts from IGF-1 production to utilization with chronic heart failure.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

IL-10-producing B cells are characterized by a specific methylation signature.

Among the family of regulatory B cells, the subset able to produce interleukin-10 (IL-10) is the most studied, yet its biology is still a matter of investigation. The DNA methylation profiling of the il-10 gene locus revealed a novel epigenetic signature characterizing murine B cells ready to respond through IL-10 synthesis: a demethylated region located 4.5 kb from the transcription starting site (TSS), that we named early IL10 regulatory region (eIL10rr). This feature allows to distinguish B cells that are immediately prone and developmentally committed to IL-10 production from those that require a persistent stimulation to exert an IL-10-mediated regulatory function. These late IL-10 producers are instead characterized by a delayed IL10 regulatory region (dIL10rr), a partially demethylated DNA portion located 9 kb upstream from the TSS. A demethylated region was also found in human IL-10-producing B cells and, very interestingly, in some B-cell malignancies, such as chronic lymphocytic leukemia and mantle cell lymphoma, characterized by an immunosuppressive microenvironment. Our findings define murine and human regulatory B cells as an epigenetically controlled functional state of mature B cell subsets and open a new perspective on IL-10 regulation in B cells in homeostasis and disease.