RESUMO
INTRODUCTION: Diabetes mellitus (DM) impairs wound healing. The aim was to determine whether DM influences mitochondrial respiration in wounded skin (WS) and non-wounded skin (NWS), in a pre-clinical wound healing model of streptozotocin (STZ)-induced diabetes. METHODS: Six weeks after diabetes induction, two wounds were created in the back of C57BL/J6 mice. Using high-resolution respirometry (HRR), oxygen flux was measured, in WS and NWS, using two substrate-uncoupler-inhibitor titration protocols, at baseline (day 0), day 3 and 10 post-wounding, in STZ-DM and non-diabetic (NDM) mice. Flux control ratios for the oxidative phosphorylation (OXPHOS) capacity were calculated. RESULTS: A significant increase in mitochondrial respiration was observed in STZ-DM skin compared to control skin at baseline. The OXPHOS capacity was decreased in WS under diabetes at day 3 post-wounding (inflammation phase). However, at day 10 post-wounding (remodeling phase), the OXPHOS capacity was higher in WS from STZ-DM compared to NDM mice, and compared to NWS from STZ-DM mice. A significant relative contribution of pyruvate, malate and glutamate (PMG) oxidation to the OXPHOS capacity was observed in WS compared to NWS from STZ-DM mice, at day 10, while the relative contribution of fatty acid oxidation to the OXPHOS capacity was higher in NWS. The OXPHOS capacity is altered in WS from STZ-DM compared to NDM mice across the healing process, and so is the substrate contribution in WS and NWS from STZ-DM mice, at each time point. CONCLUSION: HRR may be a sensitive tool to evaluate the underlying mechanisms of tissue repair during wound healing.
Assuntos
Diabetes Mellitus Experimental , Fosforilação Oxidativa , Camundongos , Animais , Diabetes Mellitus Experimental/metabolismo , Projetos Piloto , Camundongos Endogâmicos C57BL , Pele/metabolismoRESUMO
BACKGROUND: Viral respiratory infections may precipitate type 1 diabetes (T1D). A possible association between the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for COVID-19, and the incidence of T1D is being determined. This study was carried out using Portuguese registries, aiming at examining temporal trends between COVID-19 and T1D. METHODS: Hospital data, comparing the incidence before and during the COVID-19 pandemic, from children and young adults diagnosed with new-onset T1D, was acquired beginning in 2017 and until the end of 2022. Data was obtained from nine different Portuguese hospital units. The impact of the COVID-19 pandemic, beginning in March 2020, was assessed comparing the annual numbers of new-onset T1D cases. The annual median levels of glucose, glycated hemoglobin (HbA1c) and fasting C-peptide at T1D diagnosis were compared. The annual number of diabetic ketoacidosis (DKA) episodes among new T1D cases was also assessed at two centers. RESULTS: In total, data from 574 newly diagnosed T1D patients was analyzed, including 530 (92.3%) children. The mean ages for child and adult patients were 9.1 (SD 4.4) and 32.8 (SD 13.6) years, respectively. 57.8% (331/573) were male, one patient had unknown sex. The overall median (25-75 percentiles) levels of glucose, HbA1c and fasting C-peptide at diagnosis were 454 mg/dL (356-568), 11.8% (10.1-13.4) and 0.50 µg/L (0.30-0.79), respectively. DKA at T1D diagnosis was present in 48.4% (76/157). For eight centers with complete 2018 to 2021 data (all calendar months), no overall significant increase in T1D cases was observed during the COVID-19 pandemic, i.e. 90 cases in 2018, 90 cases in 2019, 112 in 2020 and 100 in 2021 (P for trend = 0.36). Two of the centers, Faro (CHUA) and Dona Estefânia (CHULC) hospitals, did however see an increase in T1D from 2019 to 2020. No significant changes in glucose (P = 0.32), HbA1c (P = 0.68), fasting C-peptide (P = 0.20) or DKA frequency (P = 0.68) at the time of T1D diagnosis were observed over the entire study period. CONCLUSION: The T1D incidence did not increase significantly, when comparing the years before and during the COVID-19 pandemic, nor did key metabolic parameters or number of DKA episodes change.
Assuntos
COVID-19 , Diabetes Mellitus Tipo 1 , Sistema de Registros , Humanos , COVID-19/epidemiologia , COVID-19/complicações , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/complicações , Masculino , Portugal/epidemiologia , Feminino , Incidência , Criança , Adulto , Adolescente , Adulto Jovem , Pré-Escolar , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/metabolismo , SARS-CoV-2 , Cetoacidose Diabética/epidemiologia , Glicemia/análise , Glicemia/metabolismoRESUMO
Diabetic foot ulcers (DFU) are one of the most frequent and debilitating complications of diabetes. DFU wound healing is a highly complex process, resulting in significant medical, economic and social challenges. Therefore, early identification of patients with a high-risk profile would be important to adequate treatment and more successful health outcomes. This study explores risk assessment profiles for DFU healing and healing prognosis, using machine learning predictive approaches and decision tree algorithms. Patients were evaluated at baseline (T0; N = 158) and 2 months later (T1; N = 108) on sociodemographic, clinical, biochemical and psychological variables. The performance evaluation of the models comprised F1-score, accuracy, precision and recall. Only profiles with F1-score >0.7 were selected for analysis. According to the two profiles generated for DFU healing, the most important predictive factors were illness representations on T1 IPQ-B (IPQ-B ≤ 9.5 and < 10.5) and the DFU duration (≤ 13 weeks). The two predictive models for DFU healing prognosis suggest that biochemical factors are the best predictors of a favorable healing prognosis, namely IL-6, microRNA-146a-5p and PECAM-1 at T0 and angiopoietin-2 at T1. Illness perception at T0 (IPQ-B ≤ 39.5) also emerged as a relevant predictor for healing prognosis. The results emphasize the importance of DFU duration, illness perception and biochemical markers as predictors of healing in chronic DFUs. Future research is needed to confirm and test the obtained predictive models.
Assuntos
Diabetes Mellitus , Pé Diabético , Úlcera do Pé , Humanos , Pé Diabético/terapia , Cicatrização , Prognóstico , Fatores de RiscoRESUMO
The imbalance of local and systemic factors in individuals with diabetes mellitus (DM) delays, or even interrupts, the highly complex and dynamic process of wound healing, leading to diabetic foot ulceration (DFU) in 15 to 25% of cases. DFU is the leading cause of non-traumatic amputations worldwide, posing a huge threat to the well-being of individuals with DM and the healthcare system. Moreover, despite all the latest efforts, the efficient management of DFUs still remains a clinical challenge, with limited success rates in treating severe infections. Biomaterial-based wound dressings have emerged as a therapeutic strategy with rising potential to handle the tricky macro and micro wound environments of individuals with DM. Indeed, biomaterials have long been related to unique versatility, biocompatibility, biodegradability, hydrophilicity, and wound healing properties, features that make them ideal candidates for therapeutic applications. Furthermore, biomaterials may be used as a local depot of biomolecules with anti-inflammatory, pro-angiogenic, and antimicrobial properties, further promoting adequate wound healing. Accordingly, this review aims to unravel the multiple functional properties of biomaterials as promising wound dressings for chronic wound healing, and to examine how these are currently being evaluated in research and clinical settings as cutting-edge wound dressings for DFU management.
Assuntos
Anti-Infecciosos , Diabetes Mellitus , Pé Diabético , Humanos , Pé Diabético/tratamento farmacológico , Materiais Biocompatíveis/uso terapêutico , Bandagens , Cicatrização , Anti-Infecciosos/uso terapêuticoRESUMO
Adipose tissue expansion and subsequent metabolic dysfunction has been considered one of the major risk factors for development of cardiometabolic disease. Epicardial adipose tissue (EAT) in particular is a unique subtype of visceral adipose tissue located on the surface of the heart, around the coronary arteries. Due to its proximity, EAT can modulate the local metabolic and immune function of cardiomyocytes and coronary arteries. Several microRNAs have been described as key players in both cardiac and vascular function that when dysregulated will contribute to dysfunction. Here we review the influence of obesity in the crosstalk between specific adipose tissue types, in particular the EAT-secreted microRNAs, as key modulators of cardiac disease progression, not only as early biomarkers but also as therapeutic targets for cardiometabolic disease.
Assuntos
Doenças Cardiovasculares , Doença da Artéria Coronariana , MicroRNAs , Tecido Adiposo/metabolismo , Doença da Artéria Coronariana/metabolismo , Humanos , Gordura Intra-Abdominal/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Pericárdio/metabolismoRESUMO
A diabetic foot ulcer (DFU) is one of the major complications of diabetes. Wound healing under diabetic conditions is often impaired. This is in part due to the excessive oxidative stress, prolonged inflammation, immune cell dysfunction, delayed re-epithelialization, and decreased angiogenesis present at the wound site. As a result of these multifactorial impaired healing pathways, it has been difficult to develop effective therapeutic strategies for DFU. Heme oxygenase-1 (HO-1) is the rate-limiting enzyme in heme degradation generating carbon monoxide (CO), biliverdin (BV) which is converted into bilirubin (BR), and iron. HO-1 is a potent antioxidant. It can act as an anti-inflammatory, proliferative, angiogenic and cytoprotective enzyme. Due to its biological functions, HO-1 plays a very important role in wound healing, in part mediated through the biologically active end products generated by its enzymatic activity, particularly CO, BV, and BR. Therapeutic strategies involving the activation of HO-1, or the topical application of its biologically active end products are important in diabetic wound healing. Therefore, HO-1 is an attractive therapeutic target for DFU treatment. This review will provide an overview and discussion of the importance of HO-1 as a therapeutic target for diabetic wound healing.
Assuntos
Diabetes Mellitus , Pé Diabético , Anti-Inflamatórios , Antioxidantes , Biliverdina/metabolismo , Biliverdina/uso terapêutico , Monóxido de Carbono/metabolismo , Pé Diabético/tratamento farmacológico , Heme/metabolismo , Heme Oxigenase (Desciclizante)/metabolismo , Heme Oxigenase-1/metabolismo , Humanos , Ferro/metabolismoRESUMO
Non-healing diabetic foot ulcers (DFUs) are a serious complication in diabetic patients. Their incidence has increased in recent years. Although there are several treatments for DFUs, they are often not effective enough to avoid amputation. Protein tyrosine phosphatase 1B (PTP1B) is expressed in most tissues and is a negative regulator of important metabolic pathways. PTP1B is overexpressed in tissues under diabetic conditions. Recently, PTP1B inhibition has been found to enhance wound healing. PTP1B inhibition decreases inflammation and bacterial infection at the wound site and promotes angiogenesis and tissue regeneration, thereby facilitating diabetic wound healing. In summary, the pharmacological modulation of PTP1B activity may help treat DFUs, suggesting that PTP1B inhibition is an outstanding therapeutic target.
Assuntos
Pé Diabético/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Indutores da Angiogênese/uso terapêutico , Animais , Anti-Infecciosos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Pé Diabético/enzimologia , Pé Diabético/microbiologia , Pé Diabético/patologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Inibidores Enzimáticos/efeitos adversos , Humanos , Mediadores da Inflamação/metabolismo , Terapia de Alvo Molecular , Neovascularização Fisiológica/efeitos dos fármacos , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Transdução de Sinais , Pele/enzimologia , Pele/microbiologia , Pele/patologiaRESUMO
Skeletal muscle mitochondrial respiration is thought to be altered in obesity, insulin resistance, and type 2 diabetes; however, the invasive nature of tissue biopsies is an important limiting factor for studying mitochondrial function. Recent findings suggest that bioenergetics profiling of circulating cells may inform on mitochondrial function in other tissues in lieu of biopsies. Thus, we sought to determine whether mitochondrial respiration in circulating cells [peripheral blood mononuclear cells (PBMCs) and platelets] reflects that of skeletal muscle fibers derived from the same subjects. PBMCs, platelets, and skeletal muscle (vastus lateralis) samples were obtained from 32 young (25-35 yr) women of varying body mass indexes. With the use of extracellular flux analysis and high-resolution respirometry, mitochondrial respiration was measured in intact blood cells as well as in permeabilized cells and permeabilized muscle fibers. Respiratory parameters were not correlated between permeabilized muscle fibers and intact PBMCs or platelets. In a subset of samples (n = 12-13) with permeabilized blood cells available, raw measures of substrate (pyruvate, malate, glutamate, and succinate)-driven respiration did not correlate between permeabilized muscle (per mg tissue) and permeabilized PBMCs (per 106 cells); however, complex I leak and oxidative phosphorylation coupling efficiency correlated between permeabilized platelets and muscle (Spearman's ρ = 0.64, P = 0.030; Spearman's ρ = 0.72, P = 0.010, respectively). Our data indicate that bioenergetics phenotypes in circulating cells cannot recapitulate muscle mitochondrial function. Select circulating cell bioenergetics phenotypes may possibly inform on overall metabolic health, but this postulate awaits validation in cohorts spanning a larger range of insulin resistance and type 2 diabetes status.
Assuntos
Células Sanguíneas/metabolismo , Mitocôndrias Musculares/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Consumo de Oxigênio/fisiologia , Adulto , Glicemia/análise , Plaquetas/metabolismo , Índice de Massa Corporal , Metabolismo Energético/fisiologia , Feminino , Humanos , Insulina/sangue , Monócitos/metabolismo , Músculo Esquelético/metabolismo , Fatores Acopladores da Fosforilação Oxidativa/metabolismo , Triglicerídeos/sangueRESUMO
BACKGROUND/AIMS: Vascular complications contribute significantly to the extensive morbidity and mortality rates observed in people with diabetes. Despite well known that the diabetic kidney and heart exhibit imbalanced angiogenesis, the mechanisms implicated in this angiogenic paradox remain unknown. In this study, we examined the angiogenic and metabolic gene expression profile (GEP) of endothelial cells (ECs) isolated from a mouse model with type1 diabetes mellitus (T1DM). METHODS: ECs were isolated from kidneys and hearts of healthy and streptozocin (STZ)-treated mice. RNA was then extracted for molecular studies. GEP of 84 angiogenic and 84 AMP-activated Protein Kinase (AMPK)-dependent genes were examined by microarrays. Real time PCR confirmed the changes observed in significantly altered genes. Microvessel density (MVD) was analysed by immunohistochemistry, fibrosis was assessed by the Sirius red histological staining and connective tissue growth factor (CTGF) was quantified by ELISA. RESULTS: The relative percentage of ECs and MVD were increased in the kidneys of T1DM animals whereas the opposite trend was observed in the hearts of diabetic mice. Accordingly, the majority of AMPK-associated genes were upregulated in kidneys and downregulated in hearts of these animals. Angiogenic GEP revealed significant differences in Tgfß, Notch signaling and Timp2 in both diabetic organs. These findings were in agreement with the angiogenesis histological assays. Fibrosis was augmented in both organs in diabetic as compared to healthy animals. CONCLUSION: Altogether, our findings indicate, for the first time, that T1DM heart and kidney ECs present opposite metabolic cues, which are accompanied by distinct angiogenic patterns. These findings enable the development of innovative organ-specific therapeutic strategies targeting diabetic-associated vascular disorders.
Assuntos
Diabetes Mellitus Experimental/patologia , Células Endoteliais/metabolismo , Microvasos/fisiologia , Animais , Fator de Crescimento do Tecido Conjuntivo/análise , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Células Endoteliais/citologia , Fibrose , Ventrículos do Coração/metabolismo , Rim/citologia , Rim/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microvasos/patologia , Miocárdio/citologia , Miocárdio/metabolismo , Neovascularização Patológica , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Receptores Notch/metabolismo , Inibidor Tecidual de Metaloproteinase-2/genética , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Transcriptoma , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
Calcineurin inhibitors are used in immunosuppressive therapy applied after transplantation, but they are associated with major metabolic side effects including the development of new onset diabetes. Previously, we have shown that the calcineurin inhibiting drugs tacrolimus and cyclosporin A reduce adipocyte and myocyte glucose uptakes by reducing the amount of glucose transporter type 4 (GLUT4) at the cell surface, due to an increased internalization rate. However, this happens without alteration in total protein and phosphorylation levels of key proteins involved in insulin signalling or in the total amount of GLUT4. The present study evaluates possible pathways involved in the altered internalization of GLUT4 and consequent reduction of glucose uptake provoked by calcineurin inhibitors in human subcutaneous adipose tissue. Short- and long-term treatments with tacrolimus, cyclosporin A or another CNI deltamethrin (herbicide) decreased basal and insulin-dependent glucose uptake in adipocytes, without any additive effects observed when added together. However, no tacrolimus effects were observed on glucose uptake when gene transcription and protein translation were inhibited. Investigation of genes potentially involved in GLUT4 trafficking showed only a small effect on ARHGEF11 gene expression (p < 0.05). In conlusion, the specific inhibition of calcineurin, but not that of protein phosphatases, decreases glucose uptake in human subcutaneous adipocytes, suggesting that calcineurin is an important regulator of glucose transport. This inhibitory effect is mediated via gene transcription or protein translation; however, expression of genes potentially involved in GLUT4 trafficking and endocytosis appears not to be involved in these effects.
Assuntos
Adipócitos/efeitos dos fármacos , Inibidores de Calcineurina/farmacologia , Calcineurina/metabolismo , Glucose/metabolismo , Adipócitos/metabolismo , Adulto , Idoso , Membrana Celular/metabolismo , Ciclosporina/farmacologia , Endocitose , Feminino , Perfilação da Expressão Gênica , Transportador de Glucose Tipo 4/metabolismo , Humanos , Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Nitrilas/farmacologia , Fosfoproteínas Fosfatases/antagonistas & inibidores , Fosforilação , Biossíntese de Proteínas/efeitos dos fármacos , Piretrinas/farmacologia , Transdução de Sinais , Gordura Subcutânea/citologia , Tacrolimo/farmacologia , Transcrição Gênica/efeitos dos fármacosRESUMO
Neurotensin, substance P, and insulin have been demonstrated to improve wound healing in vivo. However, the mechanism behind their effect is still not fully understood. This study investigates the effects leading to enhanced scratch closure by these peptides in vitro. The skin keratinocyte cell line, HaCaT, was used to test scratch closure effects of the peptides and alterations of cytokine levels. HUVEC cells were used to test the angiogenic effect of the peptides. Furthermore, clinical isolates of Staphylococcus lugdunensis were used to examine the potential antimicrobial activity of each peptide. Our results demonstrate that neurotensin, substance P, and insulin had significant migratory effects in scratch assays were neurotensin had the lowest effect. Furthermore, we investigated use of the peptides in combination. When substance P was used in combination with neurotensin, the cell migratory capacity was decreased, and the peptides showed a negative correlation (r = -0.298, P < .001). Neurotensin and insulin significantly increased levels of monocyte chemoattractant protein-1 (P < .001) secreted from white blood cells, whereas substance P showed a tendency. Interestingly, neurotensin increased the level of monocyte chemoattractant protein-1 significantly compared to substance P (P < .01). Additionally, the peptides decreased TNFα mRNA levels (P < .001) in HaCaT cells, whereas only neurotensin and insulin decreased IL-8 mRNA (P < .001) but had no significant effect on IL-6 mRNA levels. Surprisingly, substance P increased IL-6 mRNA 9-fold (P < .001). Furthermore, we demonstrate that the peptides increased angiogenesis in the HUVEC cells (P < .001). Finally, S. lugdunensis isolates were not susceptible to the peptides. We demonstrate that the peptides worked differently on HaCaT cells, but substance P acted differently than neurotensin on cytokine levels expression as well as on migration of HaCaT cells. On the contrary, neurotensin and insulin worked similarly. All of these aspects are crucial for proper wound healing, and the results suggest multiple mechanisms for wound-healing properties of these peptides.
Assuntos
Movimento Celular/efeitos dos fármacos , Insulina/farmacologia , Neurotensina/farmacologia , Substância P/farmacologia , Linhagem Celular , Citocinas/biossíntese , Humanos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Staphylococcus lugdunensis/isolamento & purificaçãoRESUMO
New onset diabetes after transplantation (NODAT) is a metabolic disorder that affects 40% of patients on immunosuppressive agent (IA) treatment, such as rapamycin (also known as sirolimus). IAs negatively modulate insulin action in peripheral tissues including skeletal muscle, liver and white fat. However, the effects of IAs on insulin sensitivity and thermogenesis in brown adipose tissue (BAT) have not been investigated. We have analyzed the impact of rapamycin on insulin signaling, thermogenic gene-expression and mitochondrial respiration in BAT. Treatment of brown adipocytes with rapamycin for 16h significantly decreased insulin receptor substrate 1 (IRS1) protein expression and insulin-mediated protein kinase B (Akt) phosphorylation. Consequently, both insulin-induced glucose transporter 4 (GLUT4) translocation to the plasma membrane and glucose uptake were decreased. Early activation of the N-terminal Janus activated kinase (JNK) was also observed, thereby increasing IRS1 Ser 307 phosphorylation. These effects of rapamycin on insulin signaling in brown adipocytes were partly prevented by a JNK inhibitor. In vivo treatment of rats with rapamycin for three weeks abolished insulin-mediated Akt phosphorylation in BAT. Rapamycin also inhibited norepinephrine (NE)-induced lipolysis, the expression of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) and uncoupling protein (UCP)-1 in brown adipocytes. Importantly, basal mitochondrial respiration, proton leak and maximal respiratory capacity were significantly decreased in brown adipocytes treated with rapamycin. In conclusion, we demonstrate, for the first time the important role of brown adipocytes as target cells of rapamycin, suggesting that insulin resistance in BAT might play a major role in NODAT development.
Assuntos
Adipócitos Marrons/efeitos dos fármacos , Glucose/metabolismo , Insulina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Proteína Desacopladora 1/metabolismo , Adipócitos Marrons/metabolismo , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Animais , Respiração Celular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Transportador de Glucose Tipo 4/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo , Resistência à Insulina/fisiologia , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Termogênese/efeitos dos fármacosRESUMO
Type 2 diabetes mellitus is a complex metabolic disease, and cardiovascular disease is a leading complication of diabetes. Epicardial adipose tissue surrounding the heart displays biochemical, thermogenic, and cardioprotective properties. However, the metabolic cross-talk between epicardial fat and the myocardium is largely unknown. This study sought to understand epicardial adipose tissue metabolism from heart failure patients with or without diabetes. We aimed to unravel possible differences in glucose and lipid metabolism between human epicardial and subcutaneous adipocytes and elucidate the potential underlying mechanisms involved in heart failure. Insulin-stimulated [(14)C]glucose uptake and isoproterenol-stimulated lipolysis were measured in isolated epicardial and subcutaneous adipocytes. The expression of genes involved in glucose and lipid metabolism was analyzed by reverse transcription-polymerase chain reaction in adipocytes. In addition, epicardial and subcutaneous fatty acid composition was analyzed by high-resolution proton nuclear magnetic resonance spectroscopy. The difference between basal and insulin conditions in glucose uptake was significantly decreased (P= 0.006) in epicardial compared with subcutaneous adipocytes. Moreover, a significant (P< 0.001) decrease in the isoproterenol-stimulated lipolysis was also observed when the two fat depots were compared, and it was strongly correlated with lipolysis, lipid storage, and inflammation-related gene expression. Moreover, the fatty acid composition of these tissues was significantly altered by diabetes. These results emphasize potential metabolic differences between both fat depots in the presence of heart failure and highlight epicardial fat as a possible therapeutic target in situ in the cardiac microenvironment.
Assuntos
Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Ácidos Graxos/metabolismo , Insuficiência Cardíaca/metabolismo , Metabolismo dos Lipídeos/fisiologia , Lipólise/fisiologia , Pericárdio/metabolismo , Adipócitos/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Agonistas Adrenérgicos beta/farmacologia , Idoso , Glicemia/efeitos dos fármacos , Radioisótopos de Carbono , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/complicações , Feminino , Glucose/metabolismo , Insuficiência Cardíaca/complicações , Humanos , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Isoproterenol/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipólise/efeitos dos fármacos , Masculino , Pessoa de Meia-IdadeRESUMO
Diabetic foot ulceration is a major complication of diabetes. Substance P (SP) is involved in wound healing, but its effect in diabetic skin wounds is unclear. We examined the effect of exogenous SP delivery on diabetic mouse and rabbit wounds. We also studied the impact of deficiency in SP or its receptor, neurokinin-1 receptor, on wound healing in mouse models. SP treatment improved wound healing in mice and rabbits, whereas the absence of SP or its receptor impaired wound progression in mice. Moreover, SP bioavailability in diabetic skin was reduced as SP gene expression was decreased, whereas the gene expression and protein levels of the enzyme that degrades SP, neutral endopeptidase, were increased. Diabetes and SP deficiency were associated with absence of an acute inflammatory response important for wound healing progression and instead revealed a persistent inflammation throughout the healing process. SP treatment induced an acute inflammatory response, which enabled the progression to the proliferative phase and modulated macrophage activation toward the M2 phenotype that promotes wound healing. In conclusion, SP treatment reverses the chronic proinflammatory state in diabetic skin and promotes healing of diabetic wounds.
Assuntos
Diabetes Mellitus Experimental/metabolismo , Neuropatias Diabéticas/metabolismo , Inflamação/metabolismo , Macrófagos/metabolismo , Substância P/metabolismo , Substância P/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Neuropatias Diabéticas/genética , Neuropatias Diabéticas/patologia , Inflamação/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Camundongos , Coelhos , Receptores da Neurocinina-1/genética , Receptores da Neurocinina-1/metabolismo , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/patologia , Substância P/genética , Cicatrização/fisiologiaRESUMO
Impaired wound healing is an important clinical problem in diabetes mellitus and results in failure to completely heal diabetic foot ulcers (DFUs), which may lead to lower extremity amputations. In the present study, collagen based dressings were prepared to be applied as support for the delivery of neurotensin (NT), a neuropeptide that acts as an inflammatory modulator in wound healing. The performance of NT alone and NT-loaded collagen matrices to treat wounds in streptozotocin (STZ) diabetic induced mice was evaluated. Results showed that the prepared dressings were not-cytotoxic up to 72h after contact with macrophages (Raw 264.7) and human keratinocyte (HaCaT) cell lines. Moreover, those cells were shown to adhere to the collagen matrices without noticeable change in their morphology. NT-loaded collagen dressings induced faster healing (17% wound area reduction) in the early phases of wound healing in diabetic wounded mice. In addition, they also significantly reduced inflammatory cytokine expression namely, TNF-α (p<0.01) and IL-1ß (p<0.01) and decreased the inflammatory infiltrate at day 3 post-wounding (inflammatory phase). After complete healing, metalloproteinase 9 (MMP-9) is reduced in diabetic skin (p<0.05) which significantly increased fibroblast migration and collagen (collagen type I, alpha 2 (COL1A2) and collagen type III, alpha 1 (COL3A1)) expression and deposition. These results suggest that collagen-based dressings can be an effective support for NT release into diabetic wound enhancing the healing process. Nevertheless, a more prominent scar is observed in diabetic wounds treated with collagen when compared to the treatment with NT alone.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Bandagens , Diabetes Mellitus Experimental/metabolismo , Neurotensina/farmacologia , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Movimento Celular , Colágeno/química , Colágeno Tipo I/genética , Colágeno Tipo I/imunologia , Colágeno Tipo III/genética , Colágeno Tipo III/imunologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/patologia , Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/imunologia , Inflamação/patologia , Inflamação/prevenção & controle , Queratinócitos/efeitos dos fármacos , Queratinócitos/imunologia , Queratinócitos/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/patologia , Masculino , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Pele/imunologia , Pele/lesões , Pele/metabolismo , Estreptozocina , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologiaRESUMO
Cyclosporin A (CsA), a calcineurin inhibitor, remain the cornerstone of immunosuppressive regimens, regardless of nephrotoxicity, which depends on the duration of drug exposure. The mechanisms and biomarkers underlying the transition from CsA-induced renal dysfunction to nephrotoxicity deserve better elucidation, and would help clinical decisions. This study aimed to clarify these issues, using a rat model of short- and long-term CsA (5 mg/kg bw/day) treatments (3 and 9 weeks, respectively). Renal function was assessed on serum and urine; kidney tissue was used for histopathological characterization and gene and/or protein expression of markers of proliferation, fibrosis and inflammation. In the short-term, creatinine and blood urea nitrogen (BUN) levels increased and clearances decreased, accompanied by glomerular filtration rate (GFR) reduction, but without kidney lesions; at that stage, CsA exposure induced proliferating cell nuclear antigen (PCNA), transforming growth factor beta 1 (TGF-ß1), factor nuclear kappa B (NF-κß) and Tumor Protein P53 (TP53) kidney mRNA up-regulation. In the long-term treatment, renal dysfunction data was accompanied by glomerular and tubulointerstitial lesions, with remarkable kidney mRNA up-regulation of the mammalian target of rapamycin (mTOR) and the antigen identified by monoclonal antibody Ki-67 (Mki67), accompanied by mTOR protein overexpression. Transition from CsA-induced renal dysfunction to nephrotoxicity is accompanied by modification of molecular mechanisms and biomarkers, being mTOR one of the key players for kidney lesion evolution, thus suggesting, by mean of molecular evidences, that early CsA replacement by mTOR inhibitors is indeed the better therapeutic choice to prevent chronic allograft nephropathy.
Assuntos
Ciclosporina/toxicidade , Imunossupressores/toxicidade , Nefropatias/etiologia , Rim/efeitos dos fármacos , Animais , Biomarcadores/metabolismo , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Ciclosporina/efeitos adversos , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Imunossupressores/efeitos adversos , Mediadores da Inflamação/metabolismo , Rim/metabolismo , Rim/fisiopatologia , Nefropatias/metabolismo , Nefropatias/patologia , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Regulação para Cima/efeitos dos fármacosRESUMO
Despite the known link between obesity and insulin resistance (IR) to chronic low-grade inflammation, new markers capable of early IR detection are needed. Immune cells are components of adipose tissue's (AT) stromal vascular fraction (SVF) that regulate AT homeostasis. The altered phenotype and function of AT-infiltrating immune cells may contribute to the development and maintenance of local AT inflammation observed under obesity-induced IR conditions. Impaired AT-specific immunometabolic function may influence the whole organism. Therefore, AT-infiltrating immune cells may be important players in the development of obesity-related metabolic complications, such as type 2 diabetes mellitus (T2DM). B and T cells, particularly CD20+ T cells, play important roles in human pathology, such as autoimmune disease and cancer. However, the question remains as to whether CD20+ T cells have an important contribution to the development of obesity-related IR. While circulating CD20+ T cells are mostly of the central memory phenotype (i.e. antigen-experienced T cells with the ability to home to secondary lymphoid organs), tissues-infiltrated CD20+ T cells are predominantly of the effector memory phenotype (i.e. antigen-experienced T cells that preferentially infiltrate peripheral tissues). The latter produce pro-inflammatory cytokines, such as IFN-γ and IL-17, which play a role in obesity-related IR development. This review describes the CD20 molecule and its presence in both B and T cells, shedding light on its ontogeny and function, in health and disease, with emphasis on AT. The link between CD20+ T cell dysregulation, obesity, and IR development supports the role of CD20+ T cells as markers of adipose tissue dysmetabolism.
Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Neoplasias , Humanos , Autoimunidade , Diabetes Mellitus Tipo 2/metabolismo , Tecido Adiposo/metabolismo , Obesidade/metabolismo , Linfócitos T/metabolismo , Inflamação/metabolismo , Neoplasias/complicações , Neoplasias/metabolismo , Neoplasias/patologia , Resistência à Insulina/genéticaRESUMO
CD20+ T cells constitute a small subset of T cells. These are found among CD4+, CD8+, CD4+CD8+, CD4-CD8- T, and TCRγδ+ T cells, and have been poorly characterized. The aim of this study was to characterize peripheral blood (PB) CD20+ T cells and compare them to their PB CD20- T cell counterparts. PB from 17 healthy individuals was collected. The distribution of CD20+ T cells among maturation-associated T cells compartments (naïve, central memory, transitional memory, effector memory, and effector T cells), their polarization, activation status, and expression of immune-regulatory proteins were evaluated by flow cytometry. Their function was also assessed, by measuring IFN-γ, TNF-α, and IL-17 production. Compared with CD20- T cells, CD20+ T cells represent a higher proportion of transitional memory cells. Furthermore, CD20+ T cells display a proinflammatory phenotype, characterized by the expansion of Th1, Th1/17, and Tc1 cell subsets , associated to a high expression of activation (CD25) and exhaustion (PD-1) markers. In addition, the simultaneous production of the proinflammatory cytokines IFN-γ, TNF-α, and IL-17 was also detected in CD4+CD20+ T cells. Our results show that CD20+ T cells are phenotypically and functionally different from CD20- T cells, suggesting that these cells are a distinct subset of T cells.
Assuntos
Antígenos CD20 , Citometria de Fluxo , Humanos , Antígenos CD20/imunologia , Masculino , Feminino , Adulto , Interferon gama , Fator de Necrose Tumoral alfa , Interleucina-17/sangue , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Ativação Linfocitária/imunologia , Pessoa de Meia-Idade , Memória Imunológica/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Receptor de Morte Celular Programada 1/imunologia , Citocinas/metabolismo , Células T de Memória/imunologia , Subunidade alfa de Receptor de Interleucina-2/imunologiaRESUMO
Obesity-related chronic low-grade inflammation may trigger insulin resistance and type 2 diabetes (T2D) development. Cells with regulatory phenotype have been shown to be reduced during obesity, especially CD4+ Treg cells. However, little is known about the CD8+ Treg cells. Therefore, we aim to characterize the CD8+ Treg cells in human peripheral blood and adipose tissue, specifically, to address the effect of obesity and insulin resistance in this regulatory immune cell population. A group of 42 participants with obesity (OB group) were recruited. Fourteen of them were evaluated pre- and post-bariatric surgery. A group of age- and sex-matched healthy volunteers (n = 12) was also recruited (nOB group). CD8+ Treg cell quantification and phenotype were evaluated by flow cytometry, in peripheral blood (PB), subcutaneous (SAT), and visceral adipose tissues (VAT). The OB group displayed a higher percentage of CD8+ Treg cells in PB, compared to the nOB. In addition, they were preferentially polarized into Tc1- and Tc1/17-like CD8+ Treg cells, compared to nOB. Moreover, SAT displayed the highest content of CD8+ Tregs infiltrated, compared to PB or VAT, while CD8+ Tregs infiltrating VAT displayed a higher percentage of cells with Tc1-like phenotype. Participants with pre-diabetes displayed a reduced percentage of TIM-3+CD8+ Tregs in circulation, and PD-1+CD8+ Tregs infiltrated in the VAT. An increase in the percentage of circulating Tc1-like CD8+ Treg cells expressing PD-1 was observed post-surgery. In conclusion, obesity induces significant alterations in CD8+ Treg cells, affecting their percentage and phenotype, as well as the expression of important immune regulatory molecules.
Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Humanos , Linfócitos T Reguladores , Diabetes Mellitus Tipo 2/metabolismo , Resistência à Insulina/genética , Receptor de Morte Celular Programada 1/metabolismo , Obesidade/metabolismo , Linfócitos T CD8-Positivos/metabolismoRESUMO
T cells play critical roles in adipose tissue (AT) inflammation. The role of CD20+T cell in AT dysfunction and their contributing to insulin resistance (IR) and type 2 diabetes progression, is not known. The aim was to characterize CD20+T cells in omental (OAT), subcutaneous (SAT) and peripheral blood (PB) from subjects with obesity (OB, n = 42), by flow cytometry. Eight subjects were evaluated before (T1) and 12 months post (T2) bariatric/metabolic surgery (BMS). PB from subjects without obesity (nOB, n = 12) was also collected. Higher percentage of CD20+T cells was observed in OAT, compared to PB or SAT, in OB-T1. CD20 expression by PB CD4+T cells was inversely correlated with adiposity markers, while follicular-like CD20+T cells were positively correlated with impaired glucose tolerance (increased HbA1c). Notably, among OB-T1, IR establishment was marked by a lower percentage and absolute number of PB CD20+T cells, compared nOB. Obesity was associated with higher percentage of activated CD20+T cells; however, OAT-infiltrated CD20+T cells from OB-T1 with diabetes displayed the lowest activation. CD20+T cells infiltrating OAT from OB-T1 displayed a phenotype towards IFN-γ-producing Th1 and Tc1 cells. After BMS, the percentage of PB CD4+CD20+T cells increased, with reduced Th1 and increased Th17 phenotype. Whereas in OAT the percentage of CD20+T cells with Th1/17 and Tc1/17 phenotypes increased. Interestingly, OAT from OB pre/post BMS maintained higher frequency of effector memory CD20+T cells. In conclusion, CD20+T cells may play a prominent role in obesity-related AT inflammation.