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1.
Front Immunol ; 12: 616215, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34447366

RESUMO

Tolerogenic vaccinations using beta-cell antigens are attractive for type 1 diabetes prevention, but clinical trials have been disappointing. This is probably due to the late timing of intervention, when multiple auto-antibodies are already present. We therefore devised a strategy to introduce the initiating antigen preproinsulin (PPI) during neonatal life, when autoimmunity is still silent and central tolerance mechanisms, which remain therapeutically unexploited, are more active. This strategy employs an oral administration of PPI-Fc, i.e. PPI fused with an IgG Fc to bind the intestinal neonatal Fc receptor (FcRn) that physiologically delivers maternal antibodies to the offspring during breastfeeding. Neonatal oral PPI-Fc vaccination did not prevent diabetes development in PPI T-cell receptor-transgenic G9C8.NOD mice. However, PPI-Fc was efficiently transferred through the intestinal epithelium in an Fc- and FcRn-dependent manner, was taken up by antigen presenting cells, and reached the spleen and thymus. Although not statistically significant, neonatal oral PPI-Fc vaccination delayed diabetes onset in polyclonal Ins2 -/-.NOD mice that spontaneously develop accelerated diabetes. Thus, this strategy shows promise in terms of systemic and thymic antigen delivery via the intestinal FcRn pathway, but the current PPI-Fc formulation/regimen requires further improvements to achieve diabetes prevention.


Assuntos
Diabetes Mellitus Experimental/prevenção & controle , Diabetes Mellitus Tipo 1/prevenção & controle , Antígenos de Histocompatibilidade Classe I/imunologia , Insulina/farmacologia , Precursores de Proteínas/farmacologia , Receptores Fc/imunologia , Proteínas Recombinantes de Fusão/farmacologia , Timo/imunologia , Administração Oral , Animais , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Antígenos de Histocompatibilidade Classe I/genética , Insulina/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Precursores de Proteínas/genética , Receptores Fc/genética , Proteínas Recombinantes de Fusão/genética
2.
Front Immunol ; 12: 633540, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34295325

RESUMO

Sepsis is one of the most common comorbidities observed in diabetic patients, associated with a deficient innate immune response. Recently, we have shown that glucagon possesses anti-inflammatory properties. In this study, we investigated if hyperglucagonemia triggered by diabetes might reduce the migration of neutrophils, increasing sepsis susceptibility. 21 days after diabetes induction by intravenous injection of alloxan, we induced moderate sepsis in Swiss-Webster mice through cecum ligation and puncture (CLP). The glucagon receptor (GcgR) antagonist des-his1-[Glu9]-glucagon amide was injected intraperitoneally 24h and 1h before CLP. We also tested the effect of glucagon on CXCL1/KC-induced neutrophil migration to the peritoneal cavity in mice. Neutrophil chemotaxis in vitro was tested using transwell plates, and the expression of total PKA and phospho-PKA was evaluated by western blot. GcgR antagonist restored neutrophil migration, reduced CFU numbers in the peritoneal cavity and improved survival rate of diabetic mice after CLP procedure, however, the treatment did no alter hyperglycemia, CXCL1/KC plasma levels and blood neutrophilia. In addition, glucagon inhibited CXCL1/KC-induced neutrophil migration to the peritoneal cavity of non-diabetic mice. Glucagon also decreased the chemotaxis of neutrophils triggered by CXCL1/KC, PAF, or fMLP in vitro. The inhibitory action of glucagon occurred in parallel with the reduction of CXCL1/KC-induced actin polymerization in neutrophils in vitro, but not CD11a and CD11b translocation to cell surface. The suppressor effect of glucagon on CXCL1/KC-induced neutrophil chemotaxis in vitro was reversed by pre-treatment with GcgR antagonist and adenylyl cyclase or PKA inhibitors. Glucagon also increased PKA phosphorylation directly in neutrophils in vitro. Furthermore, glucagon impaired zymosan-A-induced ROS production by neutrophils in vitro. Human neutrophil chemotaxis and adherence to endothelial cells in vitro were inhibited by glucagon treatment. According to our results, this inhibition was independent of CD11a and CD11b translocation to neutrophil surface or neutrophil release of CXCL8/IL-8. Altogether, our results suggest that glucagon may be involved in the reduction of neutrophil migration and increased susceptibility to sepsis in diabetic mice. This work collaborates with better understanding of the increased susceptibility and worsening of sepsis in diabetics, which can contribute to the development of new effective therapeutic strategies for diabetic septic patients.


Assuntos
Movimento Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/complicações , Suscetibilidade a Doenças/etiologia , Glucagon/administração & dosagem , Neutrófilos/efeitos dos fármacos , Sepse/etiologia , Sepse/imunologia , Adulto , Animais , Movimento Celular/imunologia , Quimiotaxia de Leucócito/efeitos dos fármacos , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/microbiologia , Feminino , Glucagon/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos , Neutrófilos/imunologia
3.
Commun Biol ; 4(1): 685, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34083739

RESUMO

Foreign body response (FBR) to biomaterials compromises the function of implants and leads to medical complications. Here, we report a hybrid alginate microcapsule (AlgXO) that attenuated the immune response after implantation, through releasing exosomes derived from human Umbilical Cord Mesenchymal Stem Cells (XOs). Upon release, XOs suppress the local immune microenvironment, where xenotransplantation of rat islets encapsulated in AlgXO led to >170 days euglycemia in immunocompetent mouse model of Type 1 Diabetes. In vitro analyses revealed that XOs suppressed the proliferation of CD3/CD28 activated splenocytes and CD3+ T cells. Comparing suppressive potency of XOs in purified CD3+ T cells versus splenocytes, we found XOs more profoundly suppressed T cells in the splenocytes co-culture, where a heterogenous cell population is present. XOs also suppressed CD3/CD28 activated human peripheral blood mononuclear cells (PBMCs) and reduced their cytokine secretion including IL-2, IL-6, IL-12p70, IL-22, and TNFα. We further demonstrate that XOs mechanism of action is likely mediated via myeloid cells and XOs suppress both murine and human macrophages partly by interfering with NFκB pathway. We propose that through controlled release of XOs, AlgXO provide a promising new platform that could alleviate the local immune response to implantable biomaterials.


Assuntos
Diabetes Mellitus Experimental/cirurgia , Diabetes Mellitus Tipo 1/cirurgia , Exossomos/imunologia , Imunidade/imunologia , Fatores Imunológicos/imunologia , Transplante das Ilhotas Pancreáticas/métodos , Animais , Células Cultivadas , Técnicas de Cocultura , Citocinas/imunologia , Citocinas/metabolismo , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/imunologia , Exossomos/metabolismo , Humanos , Hospedeiro Imunocomprometido/imunologia , Fatores Imunológicos/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/imunologia , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL , Ratos , Baço/citologia , Baço/imunologia , Baço/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transplante Heterólogo
4.
FASEB J ; 35(6): e21673, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34042213

RESUMO

Lysophosphatidylinositol (LPI) is a glycero-lysophospholipid and a natural agonist against GPR55. The roles of the LPI/GPR55 axis in the pathogenesis of inflammation have been controversial. In the present study, we attempted to elucidate the roles of the LPI/GPR55 axis in inflammation, especially the secretion of inflammatory cytokines, IL-6 and TNF-α from macrophages. We treated RAW264.7 cells and mouse peritoneal macrophages (MPMs) with LPI and observed that LPI induced the secretion of IL-6 and TNF-α from these cells, as well as the phosphorylation of p38. These responses were inhibited by treatment with CID16020046 (CID), an antagonist against GPR55, or SB202190, an inhibitor of p38 cascade or knockdown of GPR55 with siRNA. Treatment with CID or ML-193, another antagonist against GPR55, attenuated the elevation of inflammatory cytokines in the plasma or tissue of db/db mice and in a septic mouse model induced using lipopolysaccharide, suggesting contributions to the improvement of insulin resistance and protection against organ injuries by treatment with CID or ML-193, respectively. In human subjects, although the serum LPI levels were not different, the levels of LPI in the lipoprotein fractions were lower and the levels in the lipoprotein-depleted fractions were higher in subjects with diabetes. LPI bound to albumin induced the secretion of IL-6 and TNF-α from RAW264.7 cells to a greater degree than LPI bound to LDL or HDL. These results suggest that LPI, especially the albumin-bound form, induced inflammatory cytokines depending on the GPR55/p38 pathway, which might contribute to the pathogenesis of obesity-induced inflammation and acute inflammation.


Assuntos
Albuminas/metabolismo , Citocinas/metabolismo , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 2/imunologia , Mediadores da Inflamação/metabolismo , Lisofosfolipídeos/farmacologia , Macrófagos/imunologia , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Humanos , Sistema de Sinalização das MAP Quinases , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL
5.
Front Immunol ; 12: 650626, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968046

RESUMO

Systemic inflammation is related to hyperglycemia in diabetes mellitus (DM). C-C chemokine motif ligand (CCL) 4 is upregulated in type 1 & type 2 DM patients. This study aimed to investigate if CCL4 could be a potential target to improve blood sugar control in different experimental DM models. Streptozotocin-induced diabetic mice, Leprdb /JNarl diabetic mice, and C57BL/6 mice fed a high fat diet were used as the type 1 DM, type 2 DM, and metabolic syndrome model individually. Mice were randomly assigned to receive an anti-CCL4 neutralizing monoclonal antibody. The pancreatic ß-cells were treated with streptozotocin for in vitro experiments. In streptozotocin-induced diabetic mice, inhibition of CCL4 controlled blood sugar, increased serum insulin levels, increased islet cell proliferation and decreased pancreatic interleukin (IL)-6 expression. In the type 2 diabetes and metabolic syndrome models, CCL4 inhibition retarded the progression of hyperglycemia, reduced serum tumor necrosis factor (TNF)-α and IL-6 levels, and improved insulin resistance via reducing the phosphorylation of insulin receptor substrate-1 in skeletal muscle and liver tissues. CCL4 inhibition directly protected pancreatic ß-cells from streptozotocin stimulation. Furthermore, CCL4-induced IL-6 and TNF-α expressions could be abolished by siRNA of CCR2/CCR5. In summary, direct inhibition of CCL4 protected pancreatic islet cells, improved insulin resistance and retarded the progression of hyperglycemia in different experimental models, suggesting the critical role of CCL4-related inflammation in the progression of DM. Future experiments may investigate if CCL4 could be a potential target for blood sugar control in clinical DM.


Assuntos
Quimiocina CCL4/imunologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 2/imunologia , Inflamação/imunologia , Células Secretoras de Insulina/imunologia , Ilhotas Pancreáticas/imunologia , Animais , Glicemia/metabolismo , Linhagem Celular , Quimiocina CCL4/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Teste de Tolerância a Glucose , Humanos , Inflamação/metabolismo , Insulina/sangue , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Pâncreas/citologia , Pâncreas/metabolismo
6.
Aging (Albany NY) ; 13(8): 12143-12159, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33902006

RESUMO

Increased accumulation of advanced glycation end products (AGEs) in diabetic skin is closely related to delayed wound healing. Studies have shown that the concentration of AGEs is elevated in the skin tissues and not subcutaneous tissues in refractory diabetic wounds, which suggests there may be a causal relationship between the two. In the present study, in vitro experiments revealed that AGEs activated neutrophils, and the migratory and adhesive functions of neutrophils decreased once AGE levels reached a certain threshold. Different levels of AGE expression differentially affected the function of neutrophils. Messenger RNA (mRNA) sequencing analysis combined with real-time polymerase chain reaction (PCR) showed that poliovirus receptor (PVR/CD155) and CTNND1, which play a role in migration- and adhesion-related signaling pathways, were decreased following AGE stimulation. Consequently, neutrophils cannot effectively stimulate the formation of the inflammatory belt needed to remove necrotic tissues and defend against foreign microorganisms within diabetic chronic wounds. In addition, this phenomenon may be related to the differential accumulation of AGEs in different layers of the skin.


Assuntos
Complicações do Diabetes/imunologia , Diabetes Mellitus Experimental/complicações , Produtos Finais de Glicação Avançada/metabolismo , Neutrófilos/imunologia , Pele/patologia , Animais , Cateninas/metabolismo , Agregação Celular/imunologia , Linhagem Celular Tumoral , Movimento Celular/imunologia , Complicações do Diabetes/patologia , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/patologia , Humanos , Masculino , Ratos , Receptores Virais/metabolismo , Pele/citologia , Pele/imunologia , Estreptozocina/administração & dosagem , Estreptozocina/toxicidade , Cicatrização/imunologia
7.
Acta Biochim Biophys Sin (Shanghai) ; 53(6): 784-795, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-33928341

RESUMO

Autoantibody against the angiotensin II type I receptor (AT1-AA) has been found in the serum of patients with diabetes mellitus (DM). However, it remains unclear whether AT1-AA induces ß-cell apoptosis and participates in the development of DM. In this study, an AT1-AA-positive rat model was set up by active immunization, and AT1-AA IgG was purified. INS-1 cells were treated with AT1-AA, and cell viability, apoptosis, and autophagy-related proteins were detected by Cell Counting Kit-8 assay, flow cytometry, and western blot analysis, respectively. Results showed that existence of AT1-AA impaired the islet function and increased the apoptosis of pancreatic islet cells in rats, and the autophagy level in rat pancreatic islet tissues tended to increase gradually with the prolongation of immunization time. AT1-AA markedly reduced INS-1 cell viability, promoted cell apoptosis, and decreased insulin secretion in vitro. In addition, the autophagy level was gradually increased along with the prolongation of AT1-AA treatment time. Meanwhile, it was determined that treatment with autophagy inhibitor 3-methyladenine and angiotensin II type 1 receptor (AT1R) blocker telmisartan could improve insulin secretion and apoptosis in vitro and in vivo. In conclusion, it is deduced that upregulation of autophagy contributed to the AT1-AA-induced ß-cell apoptosis and islet dysfunction, and AT1R mediated the signal transduction.


Assuntos
Apoptose/efeitos dos fármacos , Autoanticorpos/imunologia , Autoanticorpos/farmacologia , Autofagia/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/imunologia , Imunoglobulina G/imunologia , Imunoglobulina G/farmacologia , Células Secretoras de Insulina/metabolismo , Receptor Tipo 1 de Angiotensina/imunologia , Adenina/análogos & derivados , Adenina/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Animais , Apoptose/imunologia , Autoanticorpos/isolamento & purificação , Autofagia/imunologia , Linhagem Celular Tumoral , Sobrevivência Celular/imunologia , Imunização/métodos , Imunoglobulina G/isolamento & purificação , Secreção de Insulina/efeitos dos fármacos , Secreção de Insulina/imunologia , Masculino , Ratos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Telmisartan/farmacologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/imunologia
8.
Int J Mol Sci ; 22(7)2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33805585

RESUMO

Extracellular vesicles (EVs) have an important role in mediating intercellular signaling in inflammation and affect the kinetics of wound healing, however, an understanding of the mechanisms regulating these responses remains limited. Therefore, we have focused on the use of cutaneous injury models in which to study the biology of EVs on the inflammatory phase of wound healing. For this, the foreign body response using sterile subcutaneous polyvinylalcohol (PVA) sponges is ideally suited for the parallel analysis of immune cells and EVs without the need for tissue dissociation, which would introduce additional variables. We have previously used this model to identify mediators of EV biogenesis, establishing that control of how EVs are made affects their payload and biological activity. These studies in normal mice led us to consider how conditions such as immunodeficiency and obsesity affect the profile of immune cells and EVs in this model using genetically defined mutant mice. Since EVs are intrinsically heterogenous in biological fluids, we have focused our studies on a novel technology, vesicle flow cytometry (vFC) to quantify changes in EVs in mouse models. Here, we show that myeloid-derived immune cells and EVs express proteins relevant in antigen presentation in PVA sponge implants that have distinct profiles in wildtype, immune-deficient (NOD scid) vs. diabetic (Leprdb) mice. Together, these results establish a foundation for the parallel analysis of both immune cells and EVs with technologies that begin to address the heterogeneity of intercellular communication in the wound bed.


Assuntos
Antígenos CD/imunologia , Vesículas Extracelulares/fisiologia , Pele/lesões , Pele/patologia , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Diabetes Mellitus Experimental/imunologia , Modelos Animais de Doenças , Vesículas Extracelulares/imunologia , Vesículas Extracelulares/patologia , Cinética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD/genética , Camundongos Endogâmicos NOD/imunologia , Camundongos Obesos/imunologia , Células Mieloides/imunologia , Álcool de Polivinil , Cicatrização/imunologia , Cicatrização/fisiologia
9.
Immunity ; 54(4): 721-736.e10, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33725478

RESUMO

Hyperglycemia and hyperlipidemia are often observed in individuals with type II diabetes (T2D) and related mouse models. One dysmetabolic biochemical consequence is the non-enzymatic reaction between sugars, lipids, and proteins, favoring protein glycation, glycoxidation, and lipoxidation. Here, we identified oxidative alterations in key components of the major histocompatibility complex (MHC) class II molecule antigen processing and presentation machinery in vivo under conditions of hyperglycemia-induced metabolic stress. These modifications were linked to epitope-specific changes in endosomal processing efficiency, MHC class II-peptide binding, and DM editing activity. Moreover, we observed some quantitative and qualitative changes in the MHC class II immunopeptidome of Ob/Ob mice on a high-fat diet compared with controls, including changes in the presentation of an apolipoprotein B100 peptide associated previously with T2D and metabolic syndrome-related clinical complications. These findings highlight a link between glycation reactions and altered MHC class II antigen presentation that may contribute to T2D complications.


Assuntos
Apresentação do Antígeno/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Estresse Fisiológico/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 2/imunologia , Modelos Animais de Doenças , Epitopos/imunologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Peptídeos/imunologia , Ligação Proteica/imunologia
10.
J Mater Chem B ; 9(11): 2631-2640, 2021 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-33683280

RESUMO

Islet cell transplantation has been an effective method for the treatment of type 1 diabetes. The transplanted islets release insulin in response to changes in blood glucose levels. The clinical application of islet transplantation, however, has been hindered because of some critical problems including immune responses to grafted islets and side effects caused by overdosed immunosuppressive drugs. Herein, surface modification technology using poly(ethylene glycol) (PEG)-dendron was proposed to safeguard islets from the host immune system. PEG-dendron was synthesized by a divergent polymerization method and utilized to cover the islet antigen surface. Successful conjugation of PEG-dendron on the islet surface was achieved without affecting islet morphology, viability, and functionality at a concentration of 1.00%. Surface modification using PEG-dendron effectively prevented protein absorption and immune activation. Foremost, it improved the survival rate of islet grafts in vivo when combined with a low dose of immunosuppressive drugs. In conclusion, PEG-dendron is a potential candidate for the surface modification of pancreatic islets to mitigate immune responses after transplantation.


Assuntos
Dendrímeros/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Imunossupressores/farmacologia , Ilhotas Pancreáticas/efeitos dos fármacos , Polietilenoglicóis/farmacologia , Animais , Dendrímeros/química , Diabetes Mellitus Experimental/imunologia , Imunossupressores/química , Ilhotas Pancreáticas/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Polietilenoglicóis/química , Ratos , Ratos Sprague-Dawley
11.
Biochem Biophys Res Commun ; 552: 164-169, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33751933

RESUMO

Human mesenchymal stem cells (MSCs) are known to have anti-inflammatory and immunomodulatory functions; thus, several MSC products have been applied as cell therapy in clinical trials worldwide. Recent studies have demonstrated that MSC spheroids have superior anti-inflammatory and immunomodulatory functions to a single cell suspension. Current methods to prepare MSC spheroids include hanging drop, concave microwell aggregation, spinner flask, and gravity circulation. However, all these methods have limitations such as low scalability, easy cell clumping, low viability, and irregular size distribution. Here, we present a nano-patterned culture plasticware named PAMcell™ 3D plate to overcome these limitations. Nano-sized silica particles (700 nm) coated with RGD peptide were arrayed into fusiform onto the PLGA film. This uniform array enabled the seeded MSCs to grow only on the silica particles, forming uniform-sized semi-spheroids within 48 h. These MSC spheroids have been shown to have enhanced stemness, anti-inflammatory, and immunomodulatory functions, as revealed by the increased expression of stem cell markers (Oct4, Sox2, and Nanog), anti-inflammatory (IL-10, TSG6, and IDO), and immunomodulatory molecules (HGF, VEGF, CXCR4) both at mRNA and protein expression levels. Furthermore, these MSC spheroids demonstrated an increased palliative effect on glycemic control in a multiple low-dose streptozotocin-induced diabetes model compared with the same number of MSC single cell suspensions. Taken together, this study presents a new method to produce uniform-sized MSC spheroids with enhanced anti-inflammatory and immunomodulatory functions in vitro and in vivo.


Assuntos
Tecido Adiposo/citologia , Anti-Inflamatórios/imunologia , Técnicas de Cultura de Células/métodos , Fatores Imunológicos/imunologia , Células-Tronco Mesenquimais/imunologia , Esferoides Celulares/imunologia , Animais , Técnicas de Cultura de Células/instrumentação , Células Cultivadas , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/terapia , Expressão Gênica/imunologia , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL , Esferoides Celulares/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/imunologia , Fatores de Transcrição/metabolismo
12.
Int Immunopharmacol ; 94: 107492, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33647823

RESUMO

Empagliflozin is a SGLT2 inhibitor that reduces the concentration of blood glucose by inhibiting glucose reabsorption and promoting glucose excretion. Interestingly, empagliflozin also has some additional benefits, including cardiovascular protection, decreasing uric acid levels and improving NAFLD-related liver injury. However, the specific mechanism by which empagliflozin ameliorates NAFLD-related liver injury, especially how empagliflozin regulates hepatic immune inflammatory responses, is still unknown. In this study, male C57BL/6J mice were fed a high-fat diet and injected with streptozotocin to establish an animal model of T2DM with NAFLD. Then, diabetic mice with NAFLD were administered empagliflozin by gavage. We found that empagliflozin ameliorated liver injury and lipid metabolism disorder in T2DM mice with NAFLD. Empagliflozin significantly enhanced autophagy in hepatic macrophages via the AMPK/mTOR signalling pathway. After blocking autophagy and AMPK activity, empagliflozin could not prevent NAFLD-related liver injury. Furthermore, the expression levels of IL-17/IL-23 axis-related molecules were inhibited by empagliflozin through enhancing macrophage autophagy. Inhibition of IL-17/IL-23 axis activity attenuated liver injury in T2DM mice with NAFLD. In summary, these results suggested that empagliflozin could significantly ameliorate NAFLD-related liver injury, through enhancing hepatic macrophage autophagy via the AMPK/mTOR signalling pathway and further inhibiting IL-17/IL-23 axis-mediated inflammatory responses. This study provides a theoretical basis for the rational application of empagliflozin to treat T2DM with NAFLD and improve the quality of life of T2DM patients with NAFLD, which will have social benefits.


Assuntos
Compostos Benzidrílicos/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Proteínas Quinases Ativadas por AMP/imunologia , Animais , Autofagia/efeitos dos fármacos , Compostos Benzidrílicos/farmacologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/imunologia , Diabetes Mellitus Tipo 2/patologia , Glucosídeos/farmacologia , Interleucina-17/imunologia , Interleucina-23/imunologia , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/imunologia , Hepatopatia Gordurosa não Alcoólica/patologia , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Serina-Treonina Quinases TOR/imunologia
13.
Acta Diabetol ; 58(7): 881-897, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33723651

RESUMO

AIMS: Liraglutide controls type 2 diabetes (T2D) and inflammation. Gut microbiota regulates the immune system and causes at least in part type 2 diabetes. We here evaluated whether liraglutide regulates T2D through both gut microbiota and immunity in dysmetabolic mice. METHODS: Diet-induced dysmetabolic mice were treated for 14 days with intraperitoneal injection of liraglutide (100 µg/kg) or with vehicle or Exendin 4 (10 µg/kg) as controls. Various metabolic parameters, the intestinal immune cells were characterized and the 16SrDNA gene sequenced from the gut. The causal role of gut microbiota was shown using large spectrum antibiotics and by colonization of germ-free mice with the gut microbiota from treated mice. RESULTS: Besides, the expected metabolic impacts liraglutide treatment induced a specific gut microbiota specific signature when compared to vehicle or Ex4-treated mice. However, liraglutide only increased glucose-induced insulin secretion, reduced the frequency of Th1 lymphocytes, and increased that of TReg in the intestine. These effects were abolished by a concomitant antibiotic treatment. Colonization of germ-free mice with gut microbiota from liraglutide-treated diabetic mice improved glucose-induced insulin secretion and regulated the intestinal immune system differently from what observed in germ-free mice colonized with microbiota from non-treated diabetic mice. CONCLUSIONS: Altogether, our result demonstrated first the influence of liraglutide on gut microbiota and the intestinal immune system which could at least in part control glucose-induced insulin secretion.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Sistema Imunitário/efeitos dos fármacos , Secreção de Insulina/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Liraglutida/farmacologia , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/microbiologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/imunologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/microbiologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
15.
Int J Immunopathol Pharmacol ; 35: 20587384211005645, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33779346

RESUMO

Protective effects of peroxiredoxin 6 (PRDX6) in RIN-m5F ß-cells and of thymulin in mice with alloxan-induced diabetes were recently reported. The present work was aimed at studying the efficiency of thymulin and PRDX6 in a type 1 diabetes mellitus model induced by streptozotocin in mice. Effects of prolonged treatment with PRDX6 or thymic peptide thymulin on diabetes development were evaluated. We assessed the effects of the drugs on the physiological status of diabetic mice by measuring blood glucose, body weight, and cell counts in several organs, as well as effects of thymulin and PRDX6 on the immune status of diabetic mice measuring concentrations of pro-inflammatory cytokines in blood plasma (TNF-α, interleukin-5 and 17, and interferon-γ), activity of NF-κB and JNK pathways, and Hsp90α expression in immune cells. Both thymulin and PRDX6 reduced the physiological impairments in diabetic mice at various levels. Thymulin and PRDX6 provide beneficial effects in the model of diabetes via very different mechanisms. Taken together, the results of our study indicated that the thymic peptide and the antioxidant enzyme have anti-inflammatory functions. As increasing evidences show diabetes mellitus as a distinct comorbidity leading to acute respiratory distress syndrome and increased mortality in patients with COVID-19 having cytokine storm, thymulin, and PRDX6 might serve as a supporting anti-inflammatory treatment in the therapy of COVID 19 in diabetic patients.


Assuntos
COVID-19 , MAP Quinase Quinase 4/metabolismo , NF-kappa B/metabolismo , Peroxirredoxina VI , Transdução de Sinais , Fator Tímico Circulante , Animais , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , COVID-19/tratamento farmacológico , COVID-19/imunologia , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/imunologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/terapia , Descoberta de Drogas , Interferon gama/sangue , Interleucinas/sangue , Camundongos , Peroxirredoxina VI/metabolismo , Peroxirredoxina VI/farmacologia , SARS-CoV-2 , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Fator Tímico Circulante/metabolismo , Fator Tímico Circulante/farmacologia , Fator de Necrose Tumoral alfa/sangue
16.
Proc Natl Acad Sci U S A ; 118(9)2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33619103

RESUMO

We evaluated the potential for a monoclonal antibody antagonist of the glucagon receptor (Ab-4) to maintain glucose homeostasis in type 1 diabetic rodents. We noted durable and sustained improvements in glycemia which persist long after treatment withdrawal. Ab-4 promoted ß-cell survival and enhanced the recovery of insulin+ islet mass with concomitant increases in circulating insulin and C peptide. In PANIC-ATTAC mice, an inducible model of ß-cell apoptosis which allows for robust assessment of ß-cell regeneration following caspase-8-induced diabetes, Ab-4 drove a 6.7-fold increase in ß-cell mass. Lineage tracing suggests that this restoration of functional insulin-producing cells was at least partially driven by α-cell-to-ß-cell conversion. Following hyperglycemic onset in nonobese diabetic (NOD) mice, Ab-4 treatment promoted improvements in C-peptide levels and insulin+ islet mass was dramatically increased. Lastly, diabetic mice receiving human islet xenografts showed stable improvements in glycemic control and increased human insulin secretion.


Assuntos
Anticorpos Monoclonais/farmacologia , Diabetes Mellitus Experimental/terapia , Células Secretoras de Glucagon/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Receptores de Glucagon/antagonistas & inibidores , Animais , Glicemia/metabolismo , Peptídeo C/metabolismo , Linhagem da Célula/efeitos dos fármacos , Transdiferenciação Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 1/terapia , Expressão Gênica , Glucagon/antagonistas & inibidores , Glucagon/metabolismo , Células Secretoras de Glucagon/metabolismo , Células Secretoras de Glucagon/patologia , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/fisiologia , Transplante das Ilhotas Pancreáticas , Camundongos , Camundongos Endogâmicos NOD , Tamanho do Órgão/efeitos dos fármacos , Receptores de Glucagon/genética , Receptores de Glucagon/metabolismo , Resultado do Tratamento
17.
Am J Physiol Renal Physiol ; 320(4): F548-F558, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33586497

RESUMO

Palmitic acid (PA) leads to lipotoxicity in type 2 diabetes and induces oxidative stress in podocytes. Oxidized cellular proteins are degraded by proteasomes. The role of proteasomes in PA- or oxidative stress-induced podocyte injury and pathogenesis of diabetic nephropathy (DN) is unknown. We investigated the effects of PA on expression of 20S and 26S proteasomes, proteasome activator 28 (PA28) regulators, and the immunoproteasome in cultured podocytes and renal cortical tissues of db/db and db/m mice using Western blot analysis. Glomerular areas and glomerular basement membrane (GBM) widths of db/db and db/m mice were examined using morphometry. Short-term incubation of PA or low levels of H2O2 upregulated only the immunoproteasome in cultured podocytes. Long-term exposure of podocytes to PA ultimately downregulated the immunoproteasome as with other proteasomes, whereas oleic acid (OA) or eicosapentaenoic acid (EPA) restored the PA-induced decreased protein levels. In db/db mice, renal cortical immunoproteasome expression with PA28α was significantly decreased compared with db/m mice, and glomerular areas and GBM widths were significantly increased compared with db/m mice. Feeding of an OA-rich olive oil or EPA-rich fish oil protected db/db mice against the reduced renal cortical immunoproteasome expression, glomerular enlargement, and GBM thickening. These results demonstrate that lipotoxicity downregulates the immunoproteasome in podocytes and kidneys in type 2 diabetes and that OA and EPA protected type 2 diabetic mice against decreased renal cortical immunoproteasome expression and the progression of DN. Given this, lipotoxicity-induced podocyte injury with impaired immunoproteasome expression appears to play an important role in the pathogenesis of DN.NEW & NOTEWORTHY In podocytes, PA rapidly induced immunoproteasome expression but ultimately decreased it, while OA and EPA restored the decreased immunoproteasome levels. In the renal cortex of type 2 diabetic mice, immunoproteasome expression was significantly decreased, whereas feeding of OA-rich olive oil or EPA-rich fish oil diets protected them against the reduced immunoproteasome expression and progression of diabetic nephropathy. Thus, lipotoxicity-induced podocyte injury with impaired immunoproteasome expression may be related to the pathogenesis of diabetic nephropathy.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Ácido Eicosapentaenoico/farmacologia , Peróxido de Hidrogênio/farmacologia , Ácido Oleico/farmacologia , Podócitos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/imunologia , Nefropatias Diabéticas/imunologia , Nefropatias Diabéticas/metabolismo , Glucose/metabolismo , Peróxido de Hidrogênio/metabolismo , Rim/metabolismo , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Podócitos/efeitos dos fármacos
18.
Toxicology ; 452: 152698, 2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33524429

RESUMO

Hyperglycemia induces low-grade systemic inflammation and immune dysregulation, leading to overstated reactions to immune stimuli and diabetes-related organ damage. Tissue inflammation is characterized by leukocyte infiltration, and T cells play crucial roles in directing leukocyte-mediated inflammatory responses. The aim of the study was to investigate the effects of dietary exposure to chlorpyrifos (CPF) on systemic and hepatic immune-cell phenotypes in C57BL/6 mice with streptozotocin (STZ)-induced diabetes. Mice received an intraperitoneal injection of STZ for 5 consecutive days to induce diabetes, and diabetic mice were given either an AIN-93-based control diet or a CPF-containing diet at doses of 0.5, 1, or 2 mg/kg body weight/day for 28 days. Results showed that dietary exposure to CPF had no influence on the body weight or the erythrocyte hemoglobin A1c level in diabetic mice. Both blood and hepatic neutrophil populations were enhanced by CPF exposure. CPF-exposed groups had lower percentages of blood T cells without altering the proportions of CD4+ and CD8+ T-cell subsets, and lower expression levels of the Bcl-2 antiapoptotic gene in the spleen. CPF exposure reduced the percentage of blood regulatory T cells (Tregs); however, the Treg population was upregulated in the liver even when hepatic T cells were not affected by CPF in diabetic mice. Hepatic expressions of Treg-related genes were suppressed in all CPF-exposed groups. Higher plasma levels of aspartate aminotransferase and expression levels of the hepatic interleukin-1ß gene were observed in diabetic mice exposed to medium and high doses of CPF. These findings suggest that dietary exposure to CPF affects the distribution of both myeloid and lymphoid immune cells in the blood and liver under hyperglycemic conditions, which may lead to hyperinflammation when encountering immune stimuli.


Assuntos
Clorpirifos/toxicidade , Diabetes Mellitus Experimental/imunologia , Exposição Dietética/efeitos adversos , Inseticidas/toxicidade , Fenótipo , Linfócitos T Reguladores/imunologia , Animais , Clorpirifos/administração & dosagem , Diabetes Mellitus Experimental/metabolismo , Hepatócitos , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/imunologia , Leucócitos/efeitos dos fármacos , Leucócitos/imunologia , Leucócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/metabolismo
19.
Clin Sci (Lond) ; 135(1): 19-34, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33399849

RESUMO

Type 1 diabetes mellitus (T1D) is a chronic autoimmune disease characterized by insulin-producing pancreatic ß-cell destruction and hyperglycemia. While monocytes and NOD-like receptor family-pyrin domain containing 3 (NLRP3) are associated with T1D onset and development, the specific receptors and factors involved in NLRP3 inflammasome activation remain unknown. Herein, we evaluated the inflammatory state of resident peritoneal macrophages (PMs) from genetically modified non-obese diabetic (NOD), NLRP3-KO, wild-type (WT) mice and in peripheral blood mononuclear cells (PBMCs) from human T1D patients. We also assessed the effect of docosahexaenoic acid (DHA) on the inflammatory status. Macrophages from STZ-induced T1D mice exhibited increased inflammatory cytokine/chemokine levels, nitric oxide (NO) secretion, NLRP3 and iNOS protein levels, and augmented glycolytic activity compared to control animals. In PMs from NOD and STZ-induced T1D mice, DHA reduced NO production and attenuated the inflammatory state. Furthermore, iNOS and IL-1ß protein expression levels and NO production were lower in the PMs from diabetic NLRP3-KO mice than from WT mice. We also observed increased IL-1ß secretion in PBMCs from T1D patients and immortalized murine macrophages treated with advanced glycation end products and palmitic acid. The present study demonstrated that the resident PMs are in a proinflammatory state characterized by increased NLRP3/iNOS pathway-mediated NO production, up-regulated proinflammatory cytokine/chemokine receptor expression and altered glycolytic activity. Notably, ex vivo treatment with DHA reverted the diabetes-induced changes and attenuated the macrophage inflammatory state. It is plausible that DHA supplementation could be employed as adjuvant therapy for treating individuals with T1D.


Assuntos
Anti-Inflamatórios/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Ácidos Docosa-Hexaenoicos/farmacologia , Inflamação/tratamento farmacológico , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos Peritoneais/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Adulto , Animais , Células Cultivadas , Citocinas/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/enzimologia , Diabetes Mellitus Tipo 1/imunologia , Feminino , Humanos , Inflamação/induzido quimicamente , Inflamação/enzimologia , Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Macrófagos Peritoneais/enzimologia , Macrófagos Peritoneais/imunologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Pessoa de Meia-Idade , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Gravidez , Transdução de Sinais , Estreptozocina
20.
Diabetes ; 70(6): 1334-1346, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33468513

RESUMO

Antigen-specific immunotherapy (ASIT) offers a targeted treatment of autoimmune diseases that selectively inhibits autoreactive lymphocytes, but there remains an unmet need for approaches that address the limited clinical efficacy of ASIT. Soluble antigen arrays (SAgAs) deliver antigenic peptides or proteins in multivalent form, attached to a hyaluronic acid backbone using either hydrolysable linkers (hSAgAs) or stable click chemistry linkers (cSAgAs). They were evaluated for the ability to block spontaneous development of disease in a nonobese diabetic mouse model of type 1 diabetes (T1D). Two peptides, a hybrid insulin peptide and a mimotope, efficiently prevented the onset of T1D when delivered in combination as SAgAs, but not individually. Relative to free peptides administered at equimolar dose, SAgAs (particularly cSAgAs) enabled a more effective engagement of antigen-specific T cells with greater persistence and induction of tolerance markers, such as CD73, interleukin-10, programmed death-1, and KLRG-1. Anaphylaxis caused by free peptides was attenuated using hSAgA and obviated using cSAgA platforms. Despite similarities, the two peptides elicited largely nonoverlapping and possibly complementary responses among endogenous T cells in treated mice. Thus, SAgAs offer a novel and promising ASIT platform superior to free peptides in inducing tolerance while mitigating risks of anaphylaxis for the treatment of T1D.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Peptídeos/farmacocinética , Análise Serial de Proteínas , Animais , Autoantígenos/imunologia , Química Click , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 1/imunologia , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Feminino , Imunoterapia/instrumentação , Imunoterapia/métodos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/farmacocinética , Peptídeos/administração & dosagem , Indução de Remissão/métodos , Solubilidade , Resultado do Tratamento
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