Function and expression of N-acetyltransferases 1 and 2 are altered in lymphocytes in type 2 diabetes and obesity.

The cytosolic enzymes N-Acetyl Transferases 1 and 2 (NATs) transfer an acetyl group from acetyl-CoA to a xenobiotic substrate. NATs are regulated at the genetic and epigenetic levels by deacetylase enzymes such as sirtuins. The enzymatic expression of NAT1, NAT2, and SIRT1 was evaluated by flow cytometry, as well as the enzymatic activity of NATs by cell culture and HPLC analysis. Six SNPs were determined through genotyping. T2D patients (n = 29) and healthy subjects (n = 25) with a median age of 57 and 50, respectively, were recruited. An increased enzyme expression and a diminished NAT2 enzymatic activity were found in cells of T2D patients compared to the control group, while NAT1 was negatively correlated with body fat percentage and BMI. In contrast, Sirtuin inhibition increased NAT2 activity, while Sirtuin agonism decreased its activity in both groups. The analysis of NAT2 SNPs showed a higher frequency of rapid acetylation haplotypes in T2D patients compared to the control group, possibly associated as a risk factor for diabetes. The enzymatic expression of CD3+NAT2+ cells was higher in the rapid acetylators group compared to the slow acetylators group. The levels and activity of NAT1 were associated with total cholesterol and triglycerides. Meanwhile, CD3+NAT2+ cells and NAT2 activity levels were associated with HbA1c and glucose levels. The results indicate that NAT2 could be involved in metabolic processes related to the development of T2D, due to its association with glucose levels, HbA1c, and the altered SIRT-NAT axis. NAT1 may be involved with dyslipidaemias in people who are overweight or obese.

Clinical Significance of the Lipid Profile Ratios and Triglyceride Glucose Index in the Diagnosis of Metabolic Syndrome.

Introduction: Metabolic syndrome (MetS) is a pathophysiological condition defined by a set of metabolic alterations such as hypertriglyceridemia, hyperglycemia, hypertension, low HDL-c levels, and visceral obesity. Its presence identifies people with an increased risk of developing cardiovascular diseases and type 2 diabetes; however, the lack of practical and reliable methods for its diagnosis limits the identification of people with this condition. In this sense, the objective of this study was to analyze the diagnostic utility of markers derived from the lipid profile [triglyceride-glucose (TyG) index and the ratios total cholesterol (TC)/high-density lipoprotein cholesterol (HDL-c), triglyceride (TG)/HDL-c, low-density lipoprotein cholesterol/HDL-c, fasting blood glucose (FBG)/HDL-c, and white blood cell/HDL-c] in the determination of MetS. Methods: A retrospective study was designed that included 619 individuals. A logistic regression model was used to evaluate the associations of the different markers with MetS, and the cutoff points of the markers were determined through an analysis of receiver operating characteristic curves and the Youden Index. Results: A positive and significant association was observed between all markers and the presence of MetS. The cutoff values for the markers that best predicted MetS were TyG ≥ 4.8 (sensitivity = 91.4%, specificity = 74.3%), TC/HDL-c ≥ 3.7 (sensitivity = 74.3%, specificity = 75.7%), TG/HDL-c ≥ 3.3 (sensitivity = 82.5%, specificity = 84.0%), and FBG/HDL-c ≥ 2.0 (sensitivity = 85.1%, specificity = 79.7%). Conclusion: Our study demonstrated the diagnostic relevance of the different markers in detecting MetS, suggesting that these ratios may be useful in clinical practice for the opportune and accurate diagnosis of MetS.

The Purinergic Landscape of Type 2 Diabetes Mellitus.

Adenosine triphosphate (ATP) is the key energy intermediate of cellular metabolic processes and a ubiquitous extracellular messenger. As an extracellular messenger, ATP acts at plasma membrane P2 receptors (P2Rs). The levels of extracellular ATP (eATP) are set by both passive and active release mechanisms and degradation processes. Under physiological conditions, eATP concentration is in the low nanomolar range but can rise to tens or even hundreds of micromoles/L at inflammatory sites. A dysregulated eATP homeostasis is a pathogenic factor in several chronic inflammatory diseases, including type 2 diabetes mellitus (T2DM). T2DM is characterized by peripheral insulin resistance and impairment of insulin production from pancreatic ß-cells in a landscape of systemic inflammation. Although various hypoglycemic drugs are currently available, an effective treatment for T2DM and its complications is not available. However, counteracting systemic inflammation is anticipated to be beneficial. The postulated eATP increase in T2DM is understood to be a driver of inflammation via P2X7 receptor (P2X7R) activation and the release of inflammatory cytokines. Furthermore, P2X7R stimulation is thought to trigger apoptosis of pancreatic ß-cells, thus further aggravating hyperglycemia. Targeting eATP and the P2X7R might be an appealing novel approach to T2DM therapy.

Chemoresistance in Breast Cancer Patients Associated With Changes in P2X7 and A2A Purinergic Receptors in CD8+ T Lymphocytes.

Breast cancer (BRCA) is the most frequent cancer type that afflicts women. Unfortunately, despite all the current therapeutic strategies, many patients develop chemoresistance hampering the efficacy of treatment. Hence, an early indicator of therapy efficacy might aid in the search for better treatment and patient survival. Although emerging evidence indicates a key role of the purinergic receptors P2X7 and A2A in cancer, less is known about their involvement in BRCA chemoresistance. In this sense, as the chemotherapeutic treatment stimulates immune system response, we evaluated the expression and function of P2X7 and A2A receptors in CD8+ T cells before and four months after BRCA patients received neoadjuvant chemotherapy. The results showed an increase in the levels of expression of P2X7 and a decrease in the expression of A2A in CD8+ T cells in non-chemoresistant (N-CHR) patients, compared to chemoresistant (CHR) patients. Interestingly, in CHR patients, reduced expression of P2X7 occurs along with a decrease in the CD62L shedding and the production of IFN-γ. In the case of the A2A function, the inhibition of IFN-γ production was not observed after chemotherapy in CHR patients. A possible relationship between the modulation of the expression and function of the P2X7 and A2A receptors was found, according to the molecular subtypes, where the patients that were triple-negative and human epidermal growth factor receptor 2 (HER2)-enriched presented more alterations. Comorbidities such as overweight/obesity and type 2 diabetes mellitus (T2DM) participate in the abnormalities detected. Our results demonstrate the importance of purinergic signaling in CD8+ T cells during chemoresistance, and it could be considered to implement personalized therapeutic strategies.

T Regulatory Cell Frequency During Maintenance Phase Chemotherapy for Pediatric Acute Lymphoblastic Leukemia.

BACKGROUND: Drugs used in cancer treatment specifically kill T regulatory cells. OBJECTIVE: To determine different phenotypes of T regulatory cells during the maintenance phase chemotherapy for pediatric acute lymphoblastic leukemia (ALL). MATERIALS: We evaluated the percentages of regulatory T cells by flow cytometry. Soluble CTLA-4 (sCTLA-4) in plasma was evaluated by ELISA assay. RESULTS: Increased percentages of CD4+CD25+ T cells, CD4+CD39+ T cells, CD4+Foxp3+ T cells, and CD4+CD25High T cells were observed in children with ALL in comparison to healthy controls. In addition, the ALL patients with >12 months of therapy showed increased CD4+CD39+ T cells compared to the ALL patients with ≤12 months and healthy controls. Similarly, the CD4+CD25+ T cells and CD4+Foxp3+ T cells increased according to maintenance therapy time. CONCLUSION: Our results showed increased percentages of regulatory T cells in pediatric ALL patients despite chemotherapy, which might be compromising the anti-leukemic cellular immune response.

Acetylcholine Upregulates Entamoeba histolytica Virulence Factors, Enhancing Parasite Pathogenicity in Experimental Liver Amebiasis.

Entamoeba histolytica is an invasive enteric protozoan, whose infections are associated to high morbidity and mortality rates. However, only less than 10% of infected patients develop invasive amebiasis. The ability of E. histolytica to adapt to the intestinal microenvironment could be determinant in triggering pathogenic behavior. Indeed, during chronic inflammation, the vagus nerve limits the immune response through the anti-inflammatory reflex, which includes acetylcholine (ACh) as one of the predominant neurotransmitters at the infection site. Consequently, the response of E. histolytica trophozoites to ACh could be implicated in the establishment of invasive disease. The aim of this study was to evaluate the effect of ACh on E. histolytica virulence. Methods include binding detection of ACh to plasma membrane, quantification of the relative expression of virulence factors by RT-PCR and western blot, evaluation of the effect of ACh in different cellular processes related to E. histolytica pathogenesis, and assessment of the capability of E. histolytica to migrate and form hepatic abscesses in hamsters. Results demonstrated that E. histolytica trophozoites bind ACh on their membrane and show a clear increase of the expression of virulence factors, that were upregulated upon stimulation with the neurotransmitter. ACh treatment increased the expression of L220, Gal/GalNAc lectin heavy subunit (170 kDa), amebapore C, cysteine proteinase 2 (ehcp-a2), and cysteine proteinase 5 (ehcp-a5). Moreover, erythrophagocytosis, cytotoxicity, and actin cytoskeleton remodeling were augmented after ACh treatment. Likewise, by assessing the formation of amebic liver abscess, we found that stimulated trophozoites to develop greater hamster hepatic lesions with multiple granulomas. In conclusion, ACh enhanced parasite pathogenicity by upregulating diverse virulence factors, thereby contributing to disease severity, and could be linked to the establishment of invasive amebiasis.

Expression and activity of AIM2-inflammasome in rheumatoid arthritis patients.

INTRODUCTION: AIM2 inflammasome activation leads to the release of IL-ß, which plays an important role in rheumatoid arthritis pathogenesis. In this work, we evaluated AIM2 expression and activity in RA patients and healthy controls. METHODS: AIM2 and RANKL expression were evaluated by flow cytometry. Inflammasome activity was determined in monocyte cultures stimulated with synthetic DNA by measuring IL-1ß levels in supernatants using an ELISA assay. The caspase-1 expression in monocytes was measured by western blot, the POP3 expression was analysed by qPCR, and serum levels of IFN-γ were evaluated using ELISA assay. RESULTS: We observed a diminution of CD14+AIM2+ cells in RA patients, associated with disease activity and evolution. Likewise, the levels of IL-1ß were increased in monocyte cultures un-stimulated and stimulated with LPS from RA patients with DAS28 ≥ 4. The Caspase-1 activity and RANKL + monocytes in RA patients were slightly increased. Finally, augmented POP3 expression and diminished IFN-γ serum levels were detected in RA patients. CONCLUSION: Our results showed that the monocytes from RA patients were prone to release IL-1ß in the absence of the AIM2 inflammasome signal. The down-regulation of AIM2 to a systemic level in RA patients might be a consequence of augmented POP3 expression and might imply the survival of pro-inflammatory cells contributing to the inflammation process.

Variability in the virulence of specific Mycobacterium tuberculosis clinical isolates alters the capacity of human dendritic cells to signal for T cells.

BACKGROUND: Once in the pulmonary alveoli, Mycobacterium tuberculosis (Mtb) enters into contact with alveolar macrophages and dendritic cells (DCs). DCs represent the link between the innate and adaptive immune system owing to their capacity to be both a sentinel and an orchestrator of the antigen-specific immune responses against Mtb. The effect that the virulence of Mtb has on the interaction between the bacilli and human DCs has not been fully explored. OBJECTIVE: To evaluate the effect of Mtb virulence on human monocyte-derived DCs. METHODS: We exposed human monocyte-derived DCs to Mtb clinical strains (isolated from an epidemiological Mtb diversity study in Mexico) bearing different degrees of virulence and evaluated the capacity of DCs to internalise the bacilli, control intracellular growth, engage cell death pathways, express markers for activation and antigen presentation, and expand to stimulate autologous CD4+ T cells proliferation. FINDINGS: In the case of the hypervirulent Mtb strain (Phenotype 1, strain 9005186, lineage 3), we report that DCs internalise and neutralise intracellular growth of the bacilli, undergo low rates of apoptosis, and contribute poorly to T-cell expansion, as compared to the H37Rv reference strain. In the case of the hypovirulent Mtb strain (Phenotype 4, strain 9985449, lineage 4), although DCs internalise and preclude proliferation of the bacilli, the DCs also display a high level of apoptosis, massive levels of apoptosis that prevent them from maintaining autologous CD4+ T cells in a co-culture system, as compared to H37Rv. MAIN CONCLUSIONS: Our findings suggest that variability in virulence among Mtb clinical strains affects the capacity of DCs to respond to pathogenic challenge and mount an immune response against it, highlighting important parallels to studies previously done in mouse models.

P2X4 receptor as a modulator in the function of P2X receptor in CD4+ T cells from peripheral blood and adipose tissue.

Obesity is characterized by immune cell infiltration and inflammation. Purinergic receptors such as P2X1, 4 and 7 are expressed on immune cells and their activation contributes with an inflammatory response. However, the simultaneous expression of P2X1, 4 and 7 during overweight or obesity have not been described. Therefore, the aim of this study was to determine single and simultaneously expression and function of the P2X1, 4 and 7 receptors in lymphocytes and CD4 + T cells from peripheral blood (PB) and adipose tissue (AT). Our results showed a higher expression of the P2X4 receptor on CD4 + T cells from PB regarding P2X7 and P2X1 receptor expression. In addition, P2X4 receptor expression on CD4 + T cells from PB and AT was increased in individuals with BMI ≥ 25 Kg/m2. Moreover, a higher simultaneous expression of the P2X4 and P2X7 receptors on CD4 + T cells from AT compared to CD4 + T cells expressing P2X1 and P2X7 receptors simultaneously. Besides, CD4 + T cells expressing P2X4 and P2X7 receptors from PB and AT were augmented in individuals with BMI ≥ 25 Kg/m2. In addition, the percentage of lymphocytes and also CD4 + T cells expressing P2X4 receptor were elevated both in PB and AT compared to cells expressing P2X7 or P2X1. However, CD4 + T cells expressing P2X4 and P2X7 were augmented in AT compared to PB. The function of the receptors showed a lower shedding of CD62 L in adipose tissue mononuclear cells (ATMC) compared with peripheral blood mononuclear cells (PBMC) and a greater participation of P2X4 in the mobilization of intracellular calcium. We concluded that it was possible to determine for the first time the simultaneous expression of purinergic receptors in ATMC, where the P2X4 receptor has a greater participation in the activation of CD4 + T cells possibly modulating the function of the other two receptors.

Variability in the virulence of specific Mycobacterium tuberculosis clinical isolates alters the capacity of human dendritic cells to signal for T cells

BACKGROUND Once in the pulmonary alveoli, Mycobacterium tuberculosis (Mtb) enters into contact with alveolar macrophages and dendritic cells (DCs). DCs represent the link between the innate and adaptive immune system owing to their capacity to be both a sentinel and an orchestrator of the antigen-specific immune responses against Mtb. The effect that the virulence of Mtb has on the interaction between the bacilli and human DCs has not been fully explored. OBJECTIVE To evaluate the effect of Mtb virulence on human monocyte-derived DCs. METHODS We exposed human monocyte-derived DCs to Mtb clinical strains (isolated from an epidemiological Mtb diversity study in Mexico) bearing different degrees of virulence and evaluated the capacity of DCs to internalise the bacilli, control intracellular growth, engage cell death pathways, express markers for activation and antigen presentation, and expand to stimulate autologous CD4+ T cells proliferation. FINDINGS In the case of the hypervirulent Mtb strain (Phenotype 1, strain 9005186, lineage 3), we report that DCs internalise and neutralise intracellular growth of the bacilli, undergo low rates of apoptosis, and contribute poorly to T-cell expansion, as compared to the H37Rv reference strain. In the case of the hypovirulent Mtb strain (Phenotype 4, strain 9985449, lineage 4), although DCs internalise and preclude proliferation of the bacilli, the DCs also display a high level of apoptosis, massive levels of apoptosis that prevent them from maintaining autologous CD4+ T cells in a co-culture system, as compared to H37Rv. MAIN CONCLUSIONS Our findings suggest that variability in virulence among Mtb clinical strains affects the capacity of DCs to respond to pathogenic challenge and mount an immune response against it, highlighting important parallels to studies previously done in mouse models.

Increased Levels of AIM2 and Circulating Mitochondrial DNA in Type 2 Diabetes.

BACKGROUND: Chronic inflammation has critical role in Type 2 diabetes (T2D), in which IL-1ß contributes in insulin resistance and beta cell dysfunction. The activation of NLRP3 and AIM2 by endogens ligands, such as mtDNA can lead to the release of active form of IL-1ß. OBJECTIVE: To evaluate AIM2 expression and activation as well as circulating mtDNA levels in T2D patients. METHODS: AIM2 expression was analyzed by flow cytometry, it's activity was assessed by measuring in vitro release of IL-1ß induced by Poly (dA:dT), and mtDNA copy number was determined by quantitative real-time polymerase chain reaction. RESULTS: Increased percent of AIM2+ cells were detected in monocytes from patients with T2D. Moreover, increased levels of IL-1ß in monocytes cultures from T2D patients compared to healthy controls were observed. Also, association between AIM2+ cells and hyperglycemia (r=0.4385, P=0.0095) and triglycerides levels (r=0.5112, P=0.002) and waist-hip ratio (r=0.4710, P=0.0049) were detected. Likewise, the mtDNA copy number was augmented in T2D patients compared to control group. The mtDNA copies number was associated with body mass index (r=0.4231, P=0.0008) and TNF-α levels (r=0.5231, P=0.0005). In addition, increased levels of IL-12p70, TNF-a, IL-10, IL-6, IL-8 and IL-1ß were detected in a serum from T2D patients. CONCLUSION: These results suggest the involvement of AIM2 and mtDNA in the inflammatory process seen in T2D.

Type-2 diabetes alters the basal phenotype of human macrophages and diminishes their capacity to respond, internalise, and control Mycobacterium tuberculosis.

BACKGROUND: Type 2 diabetes (T2D) is a risk factor for the development of tuberculosis (TB), although the associated mechanisms are not known. OBJECTIVES: To study the association between T2D and the basal phenotype of macrophages, and their immune response to Mycobacterium tuberculosis (Mtb) infection. METHODS: We evaluated the influence of T2D on the response of monocyte-derived macrophages (MDM) to Mtb in patients with T2D (n = 10) compared to healthy subjects (n = 9), before and after infection with Mtb clinical isolates bearing different degrees of virulence. The levels of cell surface markers for activation secreted cytokines and chemokines, bacterial association, and intracellular bacterial growth were evaluated. FINDINGS: The expression levels of HLA-DR, CD80, and CD86 were low while those of of PD-L1 were high in uninfected MDMs derived from patients with diabetes; as a result of Mtb infection, changes were only observed in the expression levels of PD-L1. The levels of cytokines (e.g., IL-6, IL-1ß, IL-10, and IL-12) and chemokines (e.g., MCP-1, MIG, and RANTES) are perturbed in MDMs derived from patients with diabetes, both before infection and in response to Mtb infection. In response to the more virulent Mtb strains, the levels of association and bacterial clearance were diminished in MDMs derived from patients with diabetes. CONCLUSIONS: T2D affects the basal activation state of the macrophages and its capacity to respond and control Mtb infection.

The presence of the 1068 G>A variant of P2X7 receptors is associated to an increase in IL-1Ra levels, insulin secretion and pancreatic ß-cell function but not with glycemic control in type 2 diabetes patients.

It has been reported that an increased function of the P2X7 purinergic receptor is associated with an increase in both insulin sensitivity and secretion. Accordingly, we explored the possible effect of the 1068 G>A polymorphism of the gene P2RX7 on glucose homeostasis and the levels of the anti-inflammatory cytokine IL-1Ra in T2D patients. The presence of the 1068 G>A polymorphism in T2D patients (n = 100) and healthy subjects (n = 100) was determined by DNA sequencing, and serum levels of IL-1Ra were measured by ELISA. Pancreatic ß-cell function, insulin resistance, blood glucose levels and glycated hemoglobin (HbA1c) were also analyzed. We detected a significant negative association between T2D and the 1068 G>A SNP (Odds ratio 0.3916, p = 0.0045). In addition, we observed that T2D patients bearing the 1068 G>A variant showed higher serum levels of IL-1Ra compared to both, patients with the GG genotype or healthy individuals (GG or G>A). Moreover, T2D patients bearing the 1068 G>A SNP showed increased insulin levels and a better pancreatic ß-cell function (p < 0.05 in both cases) compared to patients with the wild type genotype. However, the HbA1c levels, fasting glucose levels and the degree of insulin resistance were similar in T2D patients carrying or not the G>A SNP. Our results suggest that although the 1068 G>A polymorphism of the P2RX7 gene is associated with an increased ß-cell function and IL-1Ra release in T2D patients, the glycemic control is not significantly affected by the presence of this SNP.

Type-2 diabetes alters the basal phenotype of human macrophages and diminishes their capacity to respond, internalise, and control Mycobacterium tuberculosis

BACKGROUND Type 2 diabetes (T2D) is a risk factor for the development of tuberculosis (TB), although the associated mechanisms are not known. OBJECTIVES To study the association between T2D and the basal phenotype of macrophages, and their immune response to Mycobacterium tuberculosis (Mtb) infection. METHODS We evaluated the influence of T2D on the response of monocyte-derived macrophages (MDM) to Mtb in patients with T2D (n = 10) compared to healthy subjects (n = 9), before and after infection with Mtb clinical isolates bearing different degrees of virulence. The levels of cell surface markers for activation secreted cytokines and chemokines, bacterial association, and intracellular bacterial growth were evaluated. FINDINGS The expression levels of HLA-DR, CD80, and CD86 were low while those of of PD-L1 were high in uninfected MDMs derived from patients with diabetes; as a result of Mtb infection, changes were only observed in the expression levels of PD-L1. The levels of cytokines (e.g., IL-6, IL-1β, IL-10, and IL-12) and chemokines (e.g., MCP-1, MIG, and RANTES) are perturbed in MDMs derived from patients with diabetes, both before infection and in response to Mtb infection. In response to the more virulent Mtb strains, the levels of association and bacterial clearance were diminished in MDMs derived from patients with diabetes. CONCLUSIONS T2D affects the basal activation state of the macrophages and its capacity to respond and control Mtb infection.

LL-37, HNP-1, and HBD2/3 modulate the secretion of cytokines TNF-α, IL-6, IFN-γ, IL-10 and MMP1 in human primary cell cultures.

The aim of this study was to evaluate the effects of the LL-37, HNP-1 and HBD2/3 peptides on cytokine and MMP production in human polymorphonuclear cells, mononuclear cells and chondrocytes. The levels of cytokines in supernatants from mononuclear and polymorphonuclear cell cultures were measured with a cytometric bead array by flow cytometry. Likewise, the levels of metalloproteinase/MMP-1, 3, and 13 were measured in supernatants from chondrocyte cultures using an ELISA. The expression of RANKL on lymphocytes was analyzed by flow cytometry. We observed increased levels of TNF-α, IL-6 and IL-10 in mononuclear and polymorphonuclear cell cultures stimulated with HBD-2/3. We also observed increased levels of IFN-γ, IL-10, and IL-6 in mononuclear cell cultures stimulated with HNP-1, and increased IL-6 levels were observed in polymorphonuclear cell cultures exposed to HNP-1. We also found that the MMP-1 level increased in the chondrocyte cultures stimulated with HBD-3, whereas the MMP-1 level was decreased in cultures exposed to LL-37. The present report is the first study to determine that HNP-1and HBD2/3 promote the secretion of pro-inflammatory cytokines by polymorphonuclear and mononuclear cells and the secretion of MMP by chondrocytes, whereas LL-37 diminishes MMP1 secretion. Our results suggest that HBD-2/3 and HNP1 might play a pathological role in rheumatoid arthritis, while LL-37 might have a protective role.

Diminished levels of regulatory T cell subsets (CD8+Foxp3, CD4+Foxp3 and CD4+CD39+Foxp3) but increased Foxp3 expression in adipose tissue from overweight subjects.

OBJECTIVES: The aim of this study was to identify regulatory T cell (Treg) subsets residing in adipose tissue, demonstrate their immunosuppressive functions, and assess the possible role of Sirt1 in their function in overweight subjects. METHODS: Fat samples were obtained by lipoaspiration from healthy overweight (n = 15) and normoweight (n = 11) subjects. We obtained the stromal vascular fraction and then isolated the mononuclear cells by Ficoll-Hypaque sedimentation. The Treg subsets were analyzed by flow cytometry, the expression of Sirt1 and Foxp3 was detected by western blot, and peroxisome proliferator-activated receptor gamma (PPAR-γ) expression was evaluated by qPCR. RESULTS: We detected low numbers of Treg cell subsets displaying the phenotypes CD4+CD25-Foxp3+, CD8+CD25-Foxp3+, and CD4+CD39+Foxp3+ associated with increased body mass index in overweight subjects. We found lower levels of mRNA SIRT1 expression in adipocytes from overweight subjects than in those from normoweight subjects. In contrast, increased amounts of the Sirt1 and Foxp3 proteins in adipose tissue mononuclear cells from overweight subjects were observed. The immunosuppressive function of CD4+CD25+ Treg cells is higher in cells from obese subject than in those from normoweight subject. CONCLUSIONS: Low levels of Treg subsets in overweight subjects with a high percentage of inhibition of proliferation could be related to high levels of the Foxp3 protein. Likewise, the low expression of SIRT1 and PPAR-γ mRNA levels and increased concentration of Sirt1 proteins allows adipose tissue mononuclear cells to respond to stimuli dependent on adenosine receptors and sirtuin pathways.