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In obesity, high levels of TNF-α in the bone marrow microenvironment induce the bone marrow-mesenchymal stem cells (BM-MSCs) towards a pro-adipogenic phenotype. Here, we investigated the effect of obesity on the migratory potential of BM-MSCs and their fate towards the adipose tissues. BM-MSCs were isolated from male C57Bl/06 mice with high-fat diet-induced obesity. The migratory potential of the BM-MSCs, their presence in the subcutaneous (SAT) and the visceral adipose tissues (VAT), and the possible mechanisms involved were investigated. Obesity did not affect MSC content in the bone marrow but increased the frequency of MSCs in blood, SAT, and VAT. In these animals, the SAT adipocytes presented a larger area, without any changes in adipokine production or the Sdf-1α gene expression. In contrast, in VAT, obesity increased leptin and IL-10 levels but did not modify the size of the adipocytes. The BM-MSCs from obese animals presented increased spontaneous migratory activity. Despite the augmented expression of Cxcr4, these cells exhibited decreased migratory response towards SDF-1α, compared to that of BM-MSCs from lean mice. The PI3K-AKT pathway activation seems to mediate the migration of BM-MSCs from lean mice, but not from obese mice. Additionally, we observed an increase in the spontaneous migration of BM-MSCs from lean mice when they were co-cultured with BM-HCs from obese animals, suggesting a paracrine effect. We concluded that obesity increased the migratory potential of the BM-MSCs and induced their accumulation in VAT, which may represent an adaptive mechanism in response to chronic nutrient overload.

The significant incidence of deforestation in South America culminates in the contact of humans with typical forests species. Among these species, one may highlight Lonomia obliqua caterpillar, which, when touched by humans, can poison them through their bristles. Therefore, better acknowledging the mechanisms involved in envenomation caused by Lonomia obliqua caterpillar bristle extract (LOCBE) may contribute to further treatments. Recently, we demonstrated that LOCBE induces a pro-inflammatory profile in endothelial cells; thus, we decided to investigate the effects of LOCBE on human polymorphonuclear neutrophils (PMN), which are the first leukocytes that migrate to the inflammatory focus. Our results showed that treatment with LOCBE induced PMN chemotaxis together with alterations in actin cytoskeleton and focal adhesion kinase (FAK) activation, favoring migration. Concurrently, LOCBE induced PMN adhesion to matrix proteins, such as collagen IV, fibronectin, and fibrinogen. Moreover, we observed that LOCBE attenuated PMN apoptosis and increased reactive oxygen species (ROS) production together with nuclear factor kB (NF-κB) activation—a redox-sensitive transcription factor—as well as interleukin (IL)-1β and IL-8 release. We call attention to the ROS-dependent effect of LOCBE on increased cell migration once an antioxidant treatment reverted it. In summary, we report that LOCBE activates PMN, inducing pro-inflammatory responses modulated by ROS.

Simple Summary Increased body fat is associated with an increased risk of 13 different cancer types. Recent findings have demonstrated a close relationship between extracellular vesicles released by adipose tissues and the establishment and progression of several types of cancers and metastasis. However, detailed information about the establishment of such cooperation is still lacking. We provide evidence to support that extracellular vesicles secreted by adipose tissues may carry tumoral molecules that modulate the behavior and functions of cancer cells, as described in the seminal report “The Hallmarks of Cancer” by Hanahan and Weinberg, published in the early 2000s. Abstract Extracellular vesicles (EVs) are crucial elements that sustain the communication between tumor cells and their microenvironment, and have emerged as a widespread mechanism of tumor formation and metastasis. In obesity, the adipose tissue becomes hypertrophic and hyperplastic, triggering increased production of pro-inflammatory adipokines, such as tumor necrosis factor α, interleukin 6, interleukin 1, and leptin. Furthermore, obese adipose tissue undergoes dysregulation in the cargo content of the released EVs, resulting in an increased content of pro-inflammatory proteins, fatty acids, and oncogenic microRNAs. These alterations drive obesity-associated inflammatory responses both locally and systemically. After being ignored for a long time, adipose tissues have recently received considerable attention as a major player in tumor microenvironment-linked obesity and cancer. The role of adipose tissue in the establishment and progression of cancer is reinforced by its high plasticity and inflammatory content. Such a relationship may be established by direct contact between adipocytes and cancer cells within the microenvironment or systemically, via EV-mediated cell-to-cell communication. Here, we highlight cues evidencing the influence of adipose tissue-derived EVs on the hallmarks of cancer, which are critical for tumor malignancy.

Background In 1957, Francis Crick drew a linear diagram on a blackboard. This diagram is often called the “central dogma.” Subsequently, the relationships between different steps of the “central dogma” have been shown to be considerably complex, mostly because of the emerging world of small molecules. It is noteworthy that metabolites can be generated from the diet through gut microbiome metabolism, serve as substrates for epigenetic modifications, destabilize DNA quadruplexes, and follow Lamarckian inheritance. Small molecules were once considered the missing link in the “central dogma”; however, recently they have acquired a central role, and their general perception as downstream products has become reductionist. Metabolomics is a large-scale analysis of metabolites, and this emerging field has been shown to be the closest omics associated with the phenotype and concomitantly, the basis for all omics. Aim of review Herein, we propose a broad updated perspective for the flux of information diagram centered in metabolomics, including the influence of other factors, such as epigenomics, diet, nutrition, and the gut- microbiome. Key scientific concepts of review Metabolites are the beginning and the end of the flux of information.

Macrophage infiltration into adipose tissue (AT) is a hallmark of the chronic inflammatory response in obesity and is supported by an intense monocyte migration towards AT. Although it has been detected an increased proportion of circulating CD16+ monocyte subsets in obese subjects, the mechanisms underlying this effect and the contribution of these cells to the inflamed profile of obese AT are still poorly understood. We investigated whether factors secreted by human obese omental AT could polarize monocytes to CD16+ enriched phenotype, and how these changes could modify their migratory capacity towards adipose tissue itself. We show that explants of human obese omental AT, obtained during bariatric surgery, released higher levels of MIP1-α, TNFα, leptin and also VEGF, together with increasing amounts of microparticles (MP), when compared to explants of lean subcutaneous AT. A higher content of circulating MP derived from preadipocytes and leukocytes was also detected in plasma of obese subjects. Conditioned media or MP released from obese omental AT increased CD16 and CCR5 expression on CD14+CD16- monocytes and augmented their migratory capacity towards the conditioned media from obese omental AT, itself. This effect was inhibited when MIP1-α was neutralized. Additionally, we demonstrate that MP derived from obese omental AT carry and transfer TLR8 to monocytes, thus triggering an increase in CD16 expression in those cells. Our data shows a positive feedback loop between blood monocytes and obese omental AT, which releases chemotactic mediators and TLR8-enriched MP, thus inducing an up-regulation of CD16+ monocytes, favoring leukocyte infiltration in the obese omental AT.

Objective To investigate the role of obesity on the bone marrow microenvironment and evaluate its possible impact on the adipogenic potential of mesenchymal stem cells (MSC). Methods C57BL/6 male mice were fed with a high-fat diet (HFD) for 10 weeks. Femurs and tibiae were collected, and bone marrow mesenchymal stem cells (BM-MSC) were isolated and analyzed for proliferative potential, immunophenotype, and expression of adipogenesis markers. Their capacity to produce extracellular matrix proteins and proinflammatory cytokines in vitro was also evaluated. Results HFD mice presented a significant increase in bone marrow cellularity and higher tumor necrosis factor-α production in vitro. BM-MSC from HFD mice had higher proliferative capacity, produced more extracellular matrix proteins associated with adipogenesis, collagen I, and collagen IV, and showed increased constitutive expression of adipogenic markers, peroxisome proliferator-activated receptor-γ, and CCAAT/enhanced binding protein family-α, without changes in preadipocyte factor-1 expression. Incubation with adipocyte-differentiation medium induced further increase in CCAAT/enhanced binding protein family-α and augmented adiponectin expression in obese BM-MSC. These alterations did not result in increased adipogenic differentiation within the bone marrow. Moreover, BM-HSC from HFD mice, co-cultivated with BM-MSCs from lean mice, exerted paracrine effects on these cells, inducing augment of peroxisome proliferator-activated receptor-γ. Conclusions The data suggest that obesity promotes an inflammatory microenvironment in bone marrow that commits BM-MSC to adipogenesis.

The effects of angiotensin II (Ang II) on vascular smooth muscle cells (VSMC) are modulated by reactive oxygen species (ROS) and also involve integrin engagement. However, the potential link between alpha1beta1 integrin signaling with NOX system and their combined contribution to Ang II effects on VSMC have not been investigated. We aimed to elucidate the moslecular mechanisms underlying the activation of these two pathways in Ang II effects on VSMC.Ang II-induced VSMC migration (2-fold increase) and proliferation (2.5-fold increase) is modulated by alpha1beta1 integrin, being inhibited by obtustatin, a specific alpha1beta1 integrin blocker. Ang II also stimulates ROS production in VSMC (140%) that is NOX1 dependent, being completely inhibited in NOX1 silenced cells. The ROS production develops in two peaks, and the second peak is maintained by NOX2 activation. Apocynin and obtustatin inhibit the NOX2-associated second peak, but not the first peak of ROS production, which is related to NOX1 activation. Corroborating the involvement of alpha1beta1 integrin, the pretreatment of VSMC with obtustatin impaired Ang II-induced FAK phosphorylation, AKT activation, p21 degradation and the increase of ILK expression. Silencing of ILK blocked cell migration, AKT phosphorylation and the second peak of ROS, but partially inhibits (70%) VSMC proliferation induced by Ang II.The data demonstrate a novel role for NOX2 in Ang II effects on VSMC, and suggest alpha1beta1 integrin and ILK as target molecules to the development of more effective therapeutic interventions in cardiovascular diseases.

Envenomation caused by human contact with the caterpillar Lonomia is characterized by deleterious effects on coagulation and patency of blood vessels. The cellular effects induced by Lonomia obliqua venom highlights its capacity to activate endothelial cells, leading to a proinflammatory phenotype. Having more knowledge about the mechanisms involved in envenomation may contribute to better treatment. We aimed to evaluate the effects of Lonomia obliqua caterpillar bristle extract (LOCBE) on vascular smooth muscle cells (VSMC). We observed that LOCBE induced VSMC migration, which was preceded by alterations in actin cytoskeleton dynamics and Focal Adhesion Kinase activation. LOCBE also induced Extracellular Signal-Regulated Kinase (ERK) phosphorylation in VSMC, and the inhibition of this pathway impaired cell proliferation. Stimulation of VSMC with LOCBE triggered reactive oxygen species (ROS) production through the activation of NADPH oxidase. The rapid increase in these ROS further induced mitochondrial ROS production, however only NADPH oxidase-derived ROS were involved in ERK activation in VSMC. We that demonstrated the chemotactic and proliferative effects of LOCBE on VSMC were dependent on ROS production, mainly through NADPH oxidase. Together, the data show that Lonomia obliqua venom can interact with and activate VSMC. These effects rely on ROS production, suggesting new potential targets for treatment against vascular damage during envenomation.

Recently, we demonstrated high serum leptin and 25(OH)D (calcidiol) in obese animals, with high C/EBP β and PPAR γ expression in adipose tissue. Since the role of vitamin D in adipogenesis remains controversial and hyperleptinemia is found in obesity, we asked if leptin could interfere in vitamin D action on adipocytes. Here, we studied the direct effect of these two hormones upon 3T3L1 preadipocytes incubated with or without 1,25(OH)2D (100 nM, 24 h) and with leptin (10 −7 M, 4 h later). RT-PCR (VDR and Cyp27b1/1α-hydroxylase ), western blotting (VDR, Cyp27b1/1α-hydroxylase, ObR-b, C/EBP β , PPAR γ and Bax content), a cell proliferation assay and an Annexin V-FITC binding assay were performed. Incubation with 1,25(OH)2D decreased Cyp27b1/1α-hydroxylase and VDR. Co-incubation of 1,25(OH)2D and leptin did not change Cyp27b1/1α-hydroxylase and had no additive effect upon the decreased VDR mRNA. Incubation with 1,25(OH)2D decreased C/EBP β and PPARγ. In the cell proliferation assay, 1,25(OH)2D decreased the number of 3T3L1 cells. No changes in OBR-b or apoptotic parameters (Bax and annexin-V) were observed. The 1,25(OH)2D decreased pro-adipogenic factors and proliferation of adipocytes. However, since it inhibits the conversion of 25(OH)D to 1,25(OH)2D and VDR mRNA long-term, it could decrease the vitamin D response in adipocytes, leading to greater adipogenesis. The co-incubation of both hormones, simulating what occurs in obesity, even neutralizing the effect on Cyp27b1/ 1α- hydroxylase , did not change the vitamin D sensitivity but decreased SOCS-3 and pSTAT-3. Thus, an excess of vitamin D and hyperleptinemia could decrease vitamin D sensitivity in adipocytes, contributing to increased adipogenesis.

Macrophage infiltration into adipose tissue (AT) is a hallmark of the chronic inflammatory response in obesity and is supported by an intense monocyte migration towards AT. Although it has been detected an increased proportion of circulating CD16

Objective— Studies suggest the implication of CD16 + subpopulations (CD14 + CD16 + , CD14 dim CD16 + ) in inflammatory diseases. We aimed to determine the frequency of these subpopulations during weight loss in obesity and diabetes, conditions associated with changes in systemic inflammation, and we tested the link with subclinical atherosclerosis. Methods and Results— CD14 dim CD16 + and CD14 + CD16 + frequencies were measured by flow cytometry in lean subjects, obese subjects before and after a hypocaloric diet or gastric surgery, and obese diabetic subjects before and after gastric surgery. Both monocyte subsets were increased in obese subjects, with a significant enrichment of the CD14 dim CD16 + subpopulation in obese diabetic patients. Multivariate analysis demonstrated a link between the percentages of CD14 dim CD16 + monocytes and glycemia, independent of fat mass. Drastic weight loss led to a sharp decrease of this subset, the variations of which were strongly related to fat mass changes. A reduction of at least 5% of fat mass was sufficient to observe a significant decrease of CD14 dim CD16 + monocytes. A diminution of the CD14 + CD16 + subset was also observed during weight loss and was associated with a decrease in intima-media thickness. Conclusion— This work demonstrates a major impact of fat mass variations on CD14 dim CD16 + monocyte subsets and that the decrease in the CD14 + CD16 + subpopulation is linked to a reduction of subclinical atherosclerosis. Clinical Trial Registration— URL: http://clinicaltrials.gov . Unique identifier: NCT00476658.

Overnutrition during critical developmental periods is believed to be a risk factor for the emergence of metabolic disorders in adulthood. The present study investigated the effects of pups overfeeding during lactation on offspring's insulin secretion. To study the consequences of overnutrition early in life in rats, litter size reduction has been shown to be an appropriate experimental model. To induce early postnatal overnutrition, litter size was reduced to three pups per litter at the third day following birth [overfed group (OG)]. In the control group (CG), the litter size was adjusted to 10 pups per litter. Metabolic parameters and glucose-stimulated insulin secretion were assessed. OG pups ingested more milk at 10 and 21 days and had an augmented food intake at 1 year compared to the CG. Consistently, body weight, body fat, and fasting plasma levels of insulin were higher in 1-year-old OG rats. In addition, OG rats exhibited enhanced insulin secretion, accompanied by elevated content of GLUT-2 in pancreatic islets compared to CG. These findings indicate that early postnatal overnutrition during a critical developmental period in life may program permanent alterations in glucose-stimulated insulin secretion.

Human overnutrition has caused a rise in the prevalence of obesity in recent years. In addition to the deleterious effects of obesity during childhood, long-term effects in adulthood have been described as well. For instance, cardiovascular diseases and type 2 diabetes are among the diseases associated with a history of obesity. Altered insulin secretion and action have been described as important links between these diseases and obesity. Insulin acts as a unique anabolic hormone providing regulation of whole-body glucose homeostasis and peripheral tissue glucose uptake in tissues such as the heart. In this study, we examined insulin signaling in the heart of obese animals using an experimental model of inducing overweight adult animals by overnutrition in early life. In these animals, overfeeding during lactation was able to induce a significant increase in body weight starting at the 10th day of life, and this increased weight persisted until adulthood. Impairment in glucose tolerance, hyperinsulinemia, and an increased insulin/glucose ratio were also observed in these animals. Moreover, an increased heart weight/tibia length ratio was also observed, indicating an enlarged heart size. The overfed animals also had decreased insulin sensitivity in the heart, as confirmed by decreased insulin receptor (IR)-β and IR substrate-1 (Irs1) phosphorylation, increased phosphatase, non-receptor type 1 (Ptpn1)–IR-β association, decreased –Irs1-associated activity, and reduction in anti-phospho Akt1 phosphorylation. In conclusion, our findings showed that overnutrition during early life induced obesity and insulin resistance in the adult offspring, and further increased heart size and impaired cardiac insulin signaling, putatively due to an increase in Ptpn1 activity.

Three subpopulations of circulating monocytes have been described: CD142+CD16− (classical monocytes [CM]), CD142+CD16+ (intermediate monocytes [IM]), and CD14+CD162+ (nonclassical monocytes [NCM]). We previously showed that obesity is associated with an increased proportion of IM and NCM. Our objective is to decipher the migratory and inflammatory functions of each monocyte subset in obesity-related low-grade inflammation. Twenty-six healthy, normal-weight and nondiabetic volunteers (C) and 40 obese nondiabetic (Ob) individuals were included in this study. We explored the gene expression profile of 18 inflammatory genes in each subset of C and Ob subjects and measured protein expression of the upregulated genes. We then tested their functional response to TLR signaling in both groups. We showed an increased expression of CX3CR1 in all monocyte subpopulations and of CCR2 and CCR5 in CM and IM in the Ob group. We found negative correlation between CCR2 and CX3CR1 expressions and high-density lipoprotein-cholesterol, whereas CCR5 expression was positively linked to obesity-related metabolic traits. Production of inflammatory proteins upon bacterial LPS and viral ssRNA stimulation was higher in CM and NCM of the Ob group compared with the C group. Our work highlights an enhanced inflammatory phenotype of monocytes with a higher response to TLR4 and TLR8 stimulations in obesity. Moreover, it suggests an increased migration capacity of CM and IM subpopulations.

We investigated the consequences of mild maternal malnutrition in rat dams, in terms of thymocyte responses and the putative role of leptin. The young progeny of dams submitted to protein deprivation (PD) during lactation showed at 30 days of age lower body and thymus weights, significant alterations in CD4/CD8-defined T cell subsets without modifications in total thymocyte number as well as in proliferative response. Despite, the rats from PD group did not present alterations in leptin circulating levels, the expression of leptin receptor ObRb was enhanced in their thymocytes. This change was accompanied by an increase in leptin signaling response of thymocytes from PD rats, with an increase in JAK2 and STAT3 phosphorylation after leptin stimulation. Thymocytes from PD rats also presented a decreased rate of spontaneous apoptosis when compared to controls. Accordingly, higher expression of anti-apoptotic protein Bcl-2, and lower of pro-apoptotic protein Bax, with no change of pro-apoptotic Bad, and higher pro-caspase 3 content were detected in PD thymocytes. Moreover, thymocytes from PD group exhibited a constitutive higher nuclear content of p65 NF-kB associated to a lower IkB content in the cytoplasm. Finally, although there was no change in ob gene expression in PD thymocytes, a higher mRNA expression for the Ob gene was observed in the thymic microenvironment from PD animals. Taken together, the results show that mild maternal protein deprivation during lactation affects thymic homeostasis, enhancing leptin activity, which in turn protects thymocytes from apoptosis in the young progeny, with possible consequences upon the immune response of these animals in adult life.

Submitted by Boris INFORMAT (boris@uerj.br) on 2021-04-26T01:11:45Z No. of bitstreams: 1 Mariana Renovato Martins Tese completa.pdf: 4410821 bytes, checksum: 4ad24b517758c8557c465509e40d101f (MD5) Made available in DSpace on 2021-04-26T01:11:45Z (GMT). No. of bitstreams: 1 Mariana Renovato Martins Tese completa.pdf: 4410821 bytes, checksum: 4ad24b517758c8557c465509e40d101f (MD5) Previous issue date: 2012-02-29 Conselho Nacional de Desenvolvimento Científico e Tecnológico Obesity is a low-grade inflammatory state characterized by excessive accumulation of adipose tissue which contributes to inflammatory process. Adipose tissue macrophages (ATMs) secret different factors and are polarized into pro-inflammatory (M1) and anti-inflammatory (M2) phenotypes. Most of the ATMs derive from circulating monocytes, so monocytes play an important role in this low-grade inflammatory condition. In recent years, three subsets of monocytes have been identified: The CD14+CD16- (CMI), the CD14+CD16+ (IM) and the CD14dim CD16+ (NCM). Studies have shown an increase in CD16+ (CD14+CD16+ and CD14dimCD16+) subset in human inflammatory chronic pathologies. Recently, it was demonstrated an increase in CD16+ subsets in obesity decreasing after weight loss. Here, we show a set of data of the increased percentages and numbers of IM and NCM in obese subjects that decreased with weight loss (Poitou et al. 2011), and characterize gene expression profile of the monocyte subpopulations in obesity and suggest for the first time that the secretion derived from the obese adipose tissue induces the differentiation of CM into CD16+ monocytes. Furthermore we characterize the frequencies of the three monocytes subpopulations in obese and overweight children. The CM, IM and NCM of 6 obese subjects (OB) before and three-month after the gastric bypass, 6 obese subjects with type II diabetes (OB/D) and 7 lean subjects (C) were sorted by flow cytometry. The expression of several genes involved in monocyte functions (migration, adhesion, phagocytosis and cytokines production) was analyzed by Low Density Array. We observed an increase in the frequency of CD16+ monocytes in obese and diabetic obese subjects which decreased three months after the weight loss. The gene expression of CX3CR1 (fractalkine receptor) and of TLR8 (Toll Like Receptor 8) was highly increased in the CM, IM and NCM of the OB group and decreased after surgery. The three subsets displayed different gene expression profiles in the OB group compared to the C group: the NCM expressed high levels of CSF1R (Colony Stimulating Factor 1 receptor), TLR4, SELPLG (selectin P ligand) TNFα and IL1, the IM were characterized by over-expression of CCR2, CX3CR1, CCR5, TNFα and MCP1 and the CM expressed high levels of CCR2 (C-C chemokine receptor type 2) and CD36. Our results showed that CD14+CD16- monocytes can differentiate into CD16+ monocytes when stimulated with the conditioning media of visceral adipose tissue, suggesting a pivotal role for adipose tissue in the increased frequency of these monocytes during obesity. The three subpopulations display different gene expression patterns of molecules involved in migration, inflammation and antibody capture. CX3CR1 and TLR8 could be considered as a molecular signature reflecting modified functions of monocytes in obesity. A obesidade é definida como um acúmulo de gordura normal ou excessivo capaz de comprometer a saúde. Sabe-se que a mesma é uma condição inflamatória de baixo grau caracterizada pelo acúmulo excessivo de tecido adiposo, o que contribui para o processo inflamatório. Nesse contexto os macrófagos do tecido adiposo (ATM) secretam diversos fatores e são polarizados nos fenótipos pró-inflamatório (M1) e anti-inflamatório (M2). A maioria dos ATMs deriva de monócitos circulantes e desta forma destaca-se o importante papel dos monócitos nesse quadro de inflamação de baixo-grau. Recentemente, três subpopulações de monócitos foram identificadas: Os CD14+CD16- (MC), os CD14+CD16+ (MI) e os CD14dim CD16+ (MNC). Estudos têm demonstrado um aumento nos monócitos CD16+ (MNC e MI) em doenças inflamatórias em humanos. Recentemente, foi demonstrado que o aumento nos monócitos CD16+ também acontece na obesidade e diminui após a perda de peso. No presente trabalho apresentamos uma parte dos dados que demonstraram que as frequências dos monócitos MI e MNC estão aumentadas em obesos e diminuem com a perda de peso (Poitou e col, 2011). Além disso, caracterizamos o perfil de expressão gênica das subpopulações de monócitos na obesidade e sugerimos, pela primeira vez, que o meio condicionado do adiposo induz a diferenciação dos monócitos clássicos em monócitos CD16+. Ademais caracterizamos a frequência das três subpopulações de monócitos em crianças obesas e com sobrepeso. Os monócitos MC, MI e MNC de 6 indivíduos obesos (OB) antes e 3 meses após o by-pass gástrico (OB/AC), 6 indivíduos com diabetes do tipo II e 7 indivíduos eutróficos foram purificados por citometria de fluxo. As expressões de diversos genes envolvidos nos processos de migração, adesão, fagocitose e produção de citocinas e quimiocinas foram analisadas através da técnica de microarranjo. Observamos um aumento na frequência dos monócitos CD16+ nos indivíduos adultos obesos e obesos com diabetes, os quais estavam diminuídos três meses após a perda de peso. As expressões gênicas de CX3CR1 e de TLR8 estavam aumentadas nos monócitos MC, MI e MNC do grupo OB e diminuíram após a cirurgia. As três subpopulações de monócitos apresentaram perfis de expressão gênica diferentes no grupo OB comparado com o grupo C: os monócitos MNC expressaram níveis elevados de CSF1R, SELPLG, TLR4, TNFα e IL1β, os monócitos MI se caracterizaram pela expressão aumentada de CCR2, CX3CR1, CCR5 TNFα e MCP1 e os monócitos CD14+CD16- apresentaram níveis elevados de CCR2, CX3CR1, CD36 e TLR4. Nossos resultados demonstraram que os monócitos CD14+CD16- podem se diferenciar em monócitos CD16+ quando estimulados com o meio condicionado do tecido adiposo visceral, sugerindo uma função primordial do tecido adiposo no aumento da frequência desses monócitos durante a obesidade. As três subpopulações apresentam padrões diferentes de expressão gênica de moléculas envolvidas na migração, adesão e inflamação. Nesse contexto CX3CR1 e TLR8 podem ser considerados como uma assinatura molecular refletindo as funções monocitárias alteradas na obesidade.

Studies suggest the implication of CD16(+) subpopulations (CD14(+)CD16(+), CD14(dim)CD16(+)) in inflammatory diseases. We aimed to determine the frequency of these subpopulations during weight loss in obesity and diabetes, conditions associated with changes in systemic inflammation, and we tested the link with subclinical atherosclerosis.CD14(dim)CD16(+) and CD14(+)CD16(+) frequencies were measured by flow cytometry in lean subjects, obese subjects before and after a hypocaloric diet or gastric surgery, and obese diabetic subjects before and after gastric surgery. Both monocyte subsets were increased in obese subjects, with a significant enrichment of the CD14(dim)CD16(+) subpopulation in obese diabetic patients. Multivariate analysis demonstrated a link between the percentages of CD14(dim)CD16(+) monocytes and glycemia, independent of fat mass. Drastic weight loss led to a sharp decrease of this subset, the variations of which were strongly related to fat mass changes. A reduction of at least 5% of fat mass was sufficient to observe a significant decrease of CD14(dim)CD16(+) monocytes. A diminution of the CD14(+)CD16(+) subset was also observed during weight loss and was associated with a decrease in intima-media thickness.This work demonstrates a major impact of fat mass variations on CD14(dim)CD16(+) monocyte subsets and that the decrease in the CD14(+)CD16(+) subpopulation is linked to a reduction of subclinical atherosclerosis.URL: http://clinicaltrials.gov. Unique identifier: NCT00476658.

The data provides information in support of the research article Moraes et al., Atherosclerosis 243(2) (2015) 477–485 [1]. Here we provide data behind the mechanisms involved in Angiotensin II (Ang II) effects on vascular smooth muscle cells (VSMC). Ang II-induced VSMC ROS production is modulated by alpha1beta1 integrin. Ang II also stimulates ROS production in VSMC via p47phox, a NOX2 subunit. Furthermore, Ang II effect on VSMC migration was also inhibited by NOX2 inhibitor. We showed that obtustatin, alpha1beta1 integrin blocker, inhibited Ang II effect on p47phox activation. Ang II effect on ROS production is also PI3K dependent. Finally we showed that NOX1 and Integrin-Linked-Kinase (ILK) are crucial to NOX2 activation. The research provides information about the sequential events of NOX1/alpha1beta1 integrin/ILK/NOX2 in Ang II effects on VSMC.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais Atualmente a obesidade é um problema de saúde pública, que afetar todas as idades, classes sociais e regiões do planeta. Segundo dados da OMS de 2016, 13% da população adulta é considerada obesa. No Brasil 12,4% dos homens e 16,9% das mulheres acima de 18 anos foram considerados obesos, em 2011, pelo Ministério da Saúde. O câncer de mama é o único câncer diagnosticado em todas as regiões do planeta e, segundo a Sociedade Americana de Câncer, em 2012, o câncer de mama foi responsável por 25% dos novos casos e matou mais de meio milhão de mulheres. As brasileiras também sofrem com o tumor de mama que é o mais diagnosticado no Brasil, segundo dados de 2016 do INCA. A obesidade duplica a chance de desenvolver câncer de mama e isso está relacionado à inflamação crônica de baixo grau instaurada pelo acúmulo de gordura que recruta células inflamatórias secretoras de citocinas, quimiocinas e fatores de crescimento, aumentando a inflamação. Nesse contexto as células mamárias malignas se apropriam dessa inflamação e seus mediadores para promover sua sobrevivência, proliferação, disseminação e metástase. Para identificarmos o papel da obesidade no tumor mamário, utilizamos o modelo experimental de câncer de mama murino 4T1 em animais Balb/c fêmeas alimentadas por 16 semanas com dieta padrão ou dieta hiperlipídica (60% das quilocalorias são lipídeos). Cada animal foi pesado semanalmente e o consumo médio diario de ração foi calculado. Ao final das 16 semanas mais os 21 dias de injeção do tumor, os animais foram eutanasiados para a quantificação do peso das gorduras perigonadais e retroperitoniais e remoção dos linfonodos inguinais drenantes do tumor para realização da citometria de fluxo. Os resultados indicaram que os animais alimentados com HFD, ganharam mais peso mesmo consumindo menos ração em relação, aos animais alimentados com dieta padrão. Esse ganho de peso refletiu em uma maior adiposidade nos obesos, devido ao maior peso das gorduras perigonadais e retroperitoniais. Além disso, os animais obesos apresentaram um maior Índide de Lee em relação aos controles. Nosso trabalho indicou uma queda generalizada da resposta imune contra tumor, pois observamos uma diminuição no número de células totais dos linfonodos drenantes do tumor, refletindo num menor número de células dendríticas e macrófagos, que apresentaram menor ativação com baixas expressões dos co-estimuladores CD80 e CD86; e numa redução da resposta adaptativa, tanto no número de células efetoras como linfócitos auxiliares e citotóxicos quanto no número de células reguladoras como os linfócitos Breg e Treg. Além disso, também observamos um desbalanço entre a citocina inflamatória IFN-γ e a citocina anti-inflamatória IL-10, produzidas por linfócitos CD4+ e CD8+. Em conjunto, nossos dados nos permitem concluir que a obesidade afeta diretamente o sistema imune através da diminuição da resposta celular contra o tumor como um todo, essa regulação pode ser devido a modulação da hematopoiese e indução de células MDSC. Nowadays the obesity is a public health issue capable to affect all ages, social classes, and regions of the globe. According to data from Word Health Organization in 2014, 13% of the adult population is considered obese. In Brazil the number are also startling: in the adult population 12.4% of the men and 16.9% of women already was considered obese in 2011 by Ministry of Healthy. Breast cancer is the only one diagnosed in all regions of the planet and, according to American Society of Cancer, in 2012 this type of cancer was responsible for 25% of the new cases and killed more than half millions of women. The Brazilian women undergo by breast cancer, which is the most commonly diagnosed among Brazilian women, according data from Nacional Institute of Cancer in 2015. Is certain that the obesity duplicates the chances to develop breast cancer and it is correlated to the low grade chronic inflammation established by the fat accumulation which recruit inflammatory cells that secrete cytokine, chemokines, and growth factors, increasing the inflammation. In this context the malignant mammalian cells get hold of this inflammation and its mediators to promote its own survival, proliferation, dissemination, and metastasis. To identify the role of the obesity in malignant breast tumor, we utilized in this project the experimental murine model of breast cancer 4T1 in animals Balb/c females feed for 16 weeks with the pattern diet or high-fat diet which 60% of kilocalories coming from lipids. Each animal was weekly weighed and the individual average intake was calculated. At the end of the 16 weeks more 21 tumor days after injection, the animals were euthanized for removal of the perigonadal and retroperitoneal fat-pad and also for the removal of the draining inguinal lymph nodes of the tumor to flow cytometry analysis. The results indicate that the animals feed with HFD, had weight gain even eating less than the animals feed by control diet. This gain reflected in a major adiposity in obese animals due to higher weight of the perigonadal and retroperitoneal fat-pad. Moreover, the obese animals had a higher Lee Index on comparison of the controls animals. Our work indicated a general decrease in the immune response against the tumor because was observed a decay of the number of the total cells of the tumor lymph nodes drainage, which reflected a low number of macrophages and dendritic cells, which also presents a lower activation with low expression of co-stimulators CD80 and CD86; and a decrease in the number of cells from adaptive response effector and in regulator cells like lymphocytes Breg and Treg. In addition, was also observed an unbalancing between the inflammatory cytokine IFNv and the anti-inflammatory cytokine IL-10, produced by lymphocytes CD4+ and CD8+. Together, this data allowed us to conclude that the obesity directly affect the immune system through the reduction of the cellular response against the tumor, this setting can be due to modulation of hematopoiesis and induction of MDSC.