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1.
FASEB J ; 34(6): 7733-7744, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32277856

RESUMO

Our previous results showed that the specialized pro-resolving mediator (SPM) Resolvin D1 (RvD1) promotes resolution of inflammation in salivary glands in non-obese diabetic (NOD)/ShiLtJ, a mouse model for Sjögren's syndrome (SS). Additionally, mice lacking the RvD1 receptor ALX/FPR2 show defective innate and adaptive immune responses in salivary glands. Particularly, ALX/FPR2 KO mice exhibit exacerbated inflammation in their salivary glands in response to systemic LPS treatment. Moreover, female ALX/FPR2 KO mice show increased autoantibody production and loss of salivary gland function with age. Together, these studies suggest that an underlying SPM dysregulation could be contributing to SS progression. Therefore, we investigated whether SPM production is altered in NOD/ShiLtJ using metabololipidomics and enzyme-linked immunosorbent assay (ELISA). Our results demonstrate that SPM levels were broadly elevated in plasma collected from NOD/ShiLtJ female mice after disease onset, whereas these drastic changes did not occur in male mice. Moreover, gene expression of enzymes involved in SPM biosynthesis were altered in submandibular glands (SMG) from NOD/ShiLtJ female mice after disease onset, with 5-LOX and 12/15-LOX being downregulated and upregulated, respectively. Despite this dysregulation, the abundances of the SPM products of these enzymes (ie, RvD1 and RvD2) were unaltered in freshly isolated SMG cells suggesting that other cell populations (eg, lymphocytes) may be responsible for the overabundance of SPMs that we observed. The elevation of SPMs noted here appeared to be sex mediated, meaning that it was observed only in one sex (females). Given that SS primarily affects females (roughly 90% of diagnosed cases), these results may provide some insights into the mechanisms underlying the observed sexual dimorphism.


Assuntos
Ácidos Docosa-Hexaenoicos/metabolismo , Síndrome de Sjogren/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Modelos Animais de Doenças , Regulação para Baixo/fisiologia , Feminino , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos NOD/metabolismo , Camundongos Knockout , Receptores de Formil Peptídeo/metabolismo , Glândulas Salivares/metabolismo , Fatores Sexuais , Glândula Submandibular/metabolismo , Regulação para Cima/fisiologia
2.
J Cell Mol Med ; 24(17): 9890-9897, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32790060

RESUMO

Methionine restrictive diet may alleviate ischaemia/reperfusion (I/R)-induced myocardial injury, but its underlying mechanism remains unclear. HE staining was performed to evaluate the myocardial injury caused by I/R and the effect of methionine-restricted diet (MRD) in I/R mice. IHC and Western blot were carried out to analyse the expression of CSE, CHOP and active caspase3 in I/R mice and hypoxia/reoxygenation (H/R) cells. TUNEL assay and flow cytometry were used to assess the apoptotic status of I/R mice and H/R cells. MTT was performed to analyse the proliferation of H/R cells. H2S assay was used to evaluate the concentration of H2S in the myocardial tissues and peripheral blood of I/R mice. I/R-induced mediated myocardial injury and apoptosis were partially reversed by methionine-restricted diet (MRD) via the down-regulation of CSE expression and up-regulation of CHOP and active caspase3 expression. The decreased H2S concentration in myocardial tissues and peripheral blood of I/R mice was increased by MRD. Accordingly, in a cellular model of I/R injury established with H9C2 cells, cell proliferation was inhibited, cell apoptosis was increased, and the expressions of CSE, CHOP and active caspase3 were dysregulated, whereas NaHS treatment alleviated the effect of I/R injury in H9C2 cells in a dose-dependent manner. This study provided a deep insight into the mechanism underlying the role of MRD in I/R-induced myocardial injury.


Assuntos
Injúria Renal Aguda/metabolismo , Diabetes Mellitus Experimental/dietoterapia , Metionina/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Injúria Renal Aguda/complicações , Injúria Renal Aguda/dietoterapia , Animais , Apoptose/genética , Caspase 3/genética , Proliferação de Células/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Humanos , Rim , Metionina/genética , Camundongos , Camundongos Endogâmicos NOD/genética , Camundongos Endogâmicos NOD/metabolismo , MicroRNAs/genética , Traumatismo por Reperfusão Miocárdica/dietoterapia , Traumatismo por Reperfusão Miocárdica/etiologia , Miocárdio/metabolismo , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/dietoterapia , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais/genética , Sulfitos/farmacologia , Fator de Transcrição CHOP/genética
3.
FASEB J ; 30(3): 1328-38, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26644351

RESUMO

Obesity is characterized by a dysregulated immune system, which may causally associate with insulin resistance and type 2 diabetes. Despite widespread use of nonobese diabetic (NOD) mice, NOD with severe combined immunodeficiency (scid) mutation (SCID) mice, and SCID bearing a null mutation in the IL-2 common γ chain receptor (NSG) mice as animal models of human diseases including type 1 diabetes, the underlying metabolic effects of a genetically altered immune system are poorly understood. For this, we performed a comprehensive metabolic characterization of these mice fed chow or after 6 wk of a high-fat diet. We found that NOD mice had ∼50% less fat mass and were 2-fold more insulin sensitive, as measured by hyperinsulinemic-euglycemic clamp, than C57BL/6 wild-type mice. SCID mice were also more insulin sensitive with increased muscle glucose metabolism and resistant to diet-induced obesity due to increased energy expenditure (∼10%) and physical activity (∼40%) as measured by metabolic cages. NSG mice were completely protected from diet-induced obesity and insulin resistance with significant increases in glucose metabolism in peripheral organs. Our findings demonstrate an important role of genetic background, lymphocytes, and cytokine signaling in diet-induced obesity and insulin resistance.


Assuntos
Resistência à Insulina/fisiologia , Interleucina-2/metabolismo , Linfócitos/metabolismo , Camundongos Endogâmicos NOD/metabolismo , Obesidade/metabolismo , Animais , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Dieta Hiperlipídica/efeitos adversos , Gorduras na Dieta/efeitos adversos , Metabolismo Energético/fisiologia , Glucose/metabolismo , Técnica Clamp de Glucose/métodos , Insulina/metabolismo , Linfócitos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD/fisiologia , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Obesidade/fisiopatologia , Transdução de Sinais/fisiologia
4.
Mol Ther ; 22(4): 821-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24304965

RESUMO

BAFF (B-cell-activating factor of the tumor necrosis factor family), a pivotal cytokine for B-cell activation, is overexpressed by salivary gland (SG) epithelial cells in primary Sjogren's syndrome (pSS). ΔBAFF, a physiological inhibitor of BAFF, is a minor alternative splice variant of BAFF. A U7 RNA was reengineered to deliver antisense sequences targeting BAFF splice regions. A major decrease of BAFF messenger RNA (mRNA) and protein secretion, concomitantly with the increase of ΔBAFF mRNA, was observed in vitro. In vivo, SG retrograd instillation of nonobese diabetic mice by the modified U7 cloned into an adeno-associated virus vector significantly decreased BAFF protein expression and lymphocytic infiltrates and improved salivary flow. This study offers a rationale for localized therapeutic BAFF inhibition in pSS and represents a proof of concept of the interest of exon skipping in autoimmune diseases.


Assuntos
Fator Ativador de Células B/biossíntese , RNA Mensageiro/genética , Síndrome de Sjogren/genética , Síndrome de Sjogren/terapia , Animais , Fator Ativador de Células B/antagonistas & inibidores , Fator Ativador de Células B/genética , Linfócitos B/metabolismo , Linfócitos B/patologia , Dependovirus , Éxons/genética , Humanos , Ativação Linfocitária/genética , Camundongos , Camundongos Endogâmicos NOD/genética , Camundongos Endogâmicos NOD/metabolismo , Splicing de RNA/genética , RNA Mensageiro/antagonistas & inibidores , RNA Nuclear Pequeno/genética , Síndrome de Sjogren/patologia
5.
Int J Obes (Lond) ; 38(11): 1432-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24566854

RESUMO

BACKGROUND: Chronic inflammation in adipose tissue together with obesity induces insulin resistance. Inhibitors of chronic inflammation in adipose tissue can be a potent candidate for the treatment of diabetes; however, only a few compounds have been discovered so far. The objective of this study was to find a novel inhibitor that can suppress the inflammatory response in adipose tissue and to elucidate the intracellular signaling mechanisms of the compound. METHODS: To find the active compounds, we established an assay system to evaluate the inhibition of induced MCP-1 production in adipocyte/macrophage coculture in a plant extract library. The active compound was isolated by performing high-performance liquid chromatography (HPLC) and was determined as 4ß-hydroxywithanolide E (4ßHWE) by nuclear magnetic resonance (NMR) and mass spectroscopy (MS) spectral analyses. The effect of 4ßHWE on inflammation in adipose tissue was assessed with adipocyte culture and db/db mice. RESULTS: During the screening process, Physalis pruinosa calyx extract was found to inhibit production of MCP-1 in coculture strongly. 4ßHWE belongs to the withanolide family of compounds, and it has the strongest MCP-1 production inhibitory effect and lowest toxicity than any other withanolides in coculture. Its anti-inflammatory effect was partially dependent on the attenuation of NF-κB signaling in adipocyte. Moreover, in vivo experiments showed that the oral administration of 4ßHWE to db/db mice resulted in the inhibition of macrophage invasion and cytokine expression in adipose tissue after 2 weeks of treatment; improved the plasma adiponectin, non-esterified fatty acids and MCP-1 concentrations; and increased glucose tolerance after 3 to 4 weeks of treatment. CONCLUSIONS: These results suggest that 4ßHWE has anti-inflammatory effect via inhibition of NF-κB activation in adipocyte. Moreover, the attenuation of inflammation in adipocyte has an effect on the inhibition of macrophage accumulation in obese adipose tissue. Consequently, 4ßHWE improves impaired glucose tolerance. Thus, 4ßHWE is a useful natural anti-inflammatory compound to attenuate progression of diabetes and obesity.


Assuntos
Adipócitos/efeitos dos fármacos , Tecido Adiposo/patologia , Quimiocina CCL2/antagonistas & inibidores , Inflamação/tratamento farmacológico , Macrófagos/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Physalis/química , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Vitanolídeos/farmacologia , Células 3T3-L1 , Adipócitos/metabolismo , Adipócitos/patologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Quimiocina CCL2/biossíntese , Cromatografia Líquida de Alta Pressão , Técnicas de Cocultura , Glucose/metabolismo , Immunoblotting , Resistência à Insulina , Macrófagos/metabolismo , Masculino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos NOD/metabolismo , Ressonância Magnética Nuclear Biomolecular , Fitoterapia , Vitanolídeos/isolamento & purificação
6.
J Allergy Clin Immunol ; 131(2): 434-41.e1-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23111236

RESUMO

BACKGROUND: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening cutaneous reactions caused by drugs or infections and exhibiting widespread epidermal necrosis. Currently, there is no animal model that reproduces SJS/TEN symptoms. OBJECTIVE: We sought to develop a novel mouse model of SJS/TEN by using PBMCs and skin from patients who had recovered from SJS/TEN. METHODS: For our mouse model, patients' PBMCs were injected intravenously into immunocompromised NOD/Shi-scid, IL-2Rγ(null) (NOG) mice, followed by oral administration of a causative drug. Subsequently, to replace human skin, unaffected skin specimens obtained from patients who had recovered from SJS/TEN were grafted onto NOG mice, after which patient-derived PBMCs and the causative drug were applied. RESULTS: Mice injected with PBMCs from patients with SJS/TEN and given the causative drug showed marked conjunctival congestion and numerous cell death of conjunctival epithelium, whereas there were no symptoms in mice injected with PBMCs from patients with ordinary drug skin reactions. CD8(+) T lymphocyte-depleted PBMCs from patients with SJS/TEN did not elicit these symptoms. In addition, skin-grafted mice showed darkening of the skin-grafted areas. Cleaved caspase-3 staining showed that dead keratinocytes were more numerous in the skin-grafted mice than in the healthy control animals. CONCLUSION: We have established a novel human-oriented SJS/TEN mouse model and proved the importance of CD8(+) T lymphocytes in SJS/TEN pathogenesis. The mouse model promises to promote diagnostic and therapeutic approaches.


Assuntos
Modelos Animais de Doenças , Leucócitos Mononucleares/patologia , Camundongos Endogâmicos NOD/fisiologia , Camundongos SCID/fisiologia , Pele/patologia , Síndrome de Stevens-Johnson/patologia , Animais , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Caspase 3/metabolismo , Morte Celular/fisiologia , Epitélio/metabolismo , Epitélio/patologia , Humanos , Queratinócitos/metabolismo , Queratinócitos/patologia , Leucócitos Mononucleares/metabolismo , Camundongos , Camundongos Endogâmicos NOD/metabolismo , Camundongos SCID/metabolismo , Pele/metabolismo , Síndrome de Stevens-Johnson/metabolismo
7.
Proc Natl Acad Sci U S A ; 105(48): 18895-900, 2008 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-19015530

RESUMO

The recent development of small-molecule tyrosine kinase (TK) inhibitors offers increasing opportunities for the treatment of autoimmune diseases. In this study, we investigated the potential of this new class of drugs to treat and cure type 1 diabetes (T1D) in the NOD mouse. Treatment of prediabetic and new onset diabetic mice with imatinib (Gleevec) prevented and reversed T1D. Similar results were observed with sunitinib (Sutent), an additional approved multikinase inhibitor, suggesting that the primary target of imatinib, c-Abl, was not essential in blocking disease in this model. Additional studies with another TK inhibitor, PLX647 (targeting c-Kit and c-Fms) or an anti-c-Kit mAb showed only marginal efficacy whereas a soluble form of platelet-derived growth factor receptor (PDGFR), PDGFRbetaIg, rapidly reversed diabetes. These findings strongly suggest that inhibition of PDGFR is critical to reverse diabetes and highlight a crucial role of inflammation in the development of T1D. These conclusions were supported by the finding that the adaptive immune system was not significantly affected by imatinib treatment. Finally, and most significantly, imatinib treatment led to durable remission after discontinuation of therapy at 10 weeks in a majority of mice. Thus, long-term efficacy and tolerance is likely to depend on inhibiting a combination of tyrosine kinases supporting the use of selective kinase inhibitors as a new, potentially very attractive approach for the treatment of T1D.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Camundongos Endogâmicos NOD/metabolismo , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirimidinas/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Benzamidas , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/veterinária , Feminino , Humanos , Mesilato de Imatinib , Indóis/uso terapêutico , Leucócitos/metabolismo , Camundongos , Camundongos SCID , Pâncreas/citologia , Pâncreas/patologia , Proteínas Tirosina Quinases/metabolismo , Pirróis/uso terapêutico , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Indução de Remissão , Sunitinibe
8.
J Diabetes Res ; 2021: 6581213, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778464

RESUMO

Although type 1 diabetes is thought to be an organ-specific autoimmune disease, mediated by effective CD4+ and CD8+ T cells, it has recently become clear that B cells participate in the initiation and progress of this disease. Indeed, B cell deletion can prevent or reverse autoimmune diabetes in nonobese diabetic mice and even result in partially remaining ß cell function in patients with new-onset type 1 diabetes. This review summarizes the dual role of B cells in this process not only of pathogenic effect but also of immunoregulatory function in type 1 diabetes. We focus on the impact that B cells have on regulating the activation, proliferation, and cytokine production of self-reactive T cells along with regulatory T cells, with the aim of providing a better understanding of the interactions between T and B cells in immunopathogenesis and improving the efficacy of interventions for clinical practice.


Assuntos
Linfócitos B/fisiologia , Diabetes Mellitus Tipo 1/terapia , Linfócitos T/metabolismo , Animais , Linfócitos B/citologia , Diabetes Mellitus Tipo 1/fisiopatologia , Ativação Linfocitária/fisiologia , Camundongos , Camundongos Endogâmicos NOD/metabolismo , Linfócitos T/citologia
9.
Biochim Biophys Acta Mol Basis Dis ; 1867(12): 166266, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34481869

RESUMO

Sexual dimorphism exists in the onset and development of type 1 diabetes (T1D), but its potential pathological mechanism is poorly understood. In the present study, we examined sex-specific changes in the gut microbiome and host metabolome of T1D mice via 16S rRNA gene sequencing and nuclear magnetic resonance (NMR)-based metabolomics approach, and aimed to investigate potential mechanism of the gut microbiota-host metabolic interaction in the sexual dimorphism of T1D. Our results demonstrate that female mice had a greater shift in the gut microbiota than male mice during the development of T1D; however, host metabolome was more susceptible to T1D in male mice. The correlation network analysis indicates that T1D-induced host metabolic changes may be regulated by the gut microbiota in a sex-specific manner, mainly involving short-chain fatty acids (SCFAs) metabolism, energy metabolism, amino acid metabolism, and choline metabolism. Therefore, our study suggests that sex-dependent "gut microbiota-host metabolism axis" may be implicated in the sexual dimorphism of T1D, and the link between microbes and metabolites might contribute to the prevention and treatment of T1D.


Assuntos
Diabetes Mellitus Tipo 1/genética , Ácidos Graxos Voláteis/genética , Microbioma Gastrointestinal/genética , Metaboloma/genética , Animais , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patologia , Ácidos Graxos Voláteis/metabolismo , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Metabolômica , Camundongos , Camundongos Endogâmicos NOD/genética , Camundongos Endogâmicos NOD/metabolismo , Caracteres Sexuais
10.
Clin Transl Med ; 11(11): e577, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34841716

RESUMO

Drug resistance is a major hurdle for the effectiveness of tamoxifen (TAM) to provide clinical benefit. Therefore, it is essential to identify a sensitizer that could be used to improve TAM efficacy in treating TAM-resistant breast cancer. Here, we investigated the ability of baicalein to reverse TAM resistance. We found that baicalein increased the efficacy of TAM in inhibiting proliferation and inducing apoptosis of TAM-resistant cells. It also enhanced the TAM-induced growth reduction of resistant cells from NOD/SCID mouse mammary fat pads, without causing obvious systemic toxicity. Analyses using the CellMiner tool and the Kaplan-Meier plotter database showed that HIF-1α expression was inversely correlated with TAM therapeutic response in NCI-60 cancer cells and breast cancer patients. HIF-1α expression was increased in TAM-resistant cells due to an increase in mRNA levels and reduced ubiquitin-mediated degradation. Baicalein reduced HIF-1α expression by promoting its interaction with PHD2 and pVHL, thus facilitating ubiquitin ligase-mediated proteasomal degradation and thereby suppressing the nuclear translocation, binding to the hypoxia-response element, and transcriptional activity of HIF-1α. As a result, baicalein downregulated aerobic glycolysis by restricting glucose uptake, lactate production, ATP generation, lactate/pyruvate ratio and expression of HIF-1α-targeted glycolytic genes, thereby enhancing the antiproliferative efficacy of TAM. Furthermore, baicalein interfered with HIF-1α inhibition of mitochondrial biosynthesis, which increased mitochondrial DNA content and mitochondrial numbers, restored the generation of reactive oxygen species in mitochondria, and thus enhanced the TAM-induced mitochondrial apoptotic pathway. The HIF-1α stabilizer dimethyloxallyl glycine prevented the baicalein-induced downregulation of glycolysis and mitochondrial biosynthesis and reduced the effects of baicalein on reversing TAM resistance. Our results indicate that baicalein is a promising candidate to help overcome TAM resistance by sensitizing resistant cells to TAM-induced growth inhibition and apoptosis. The mechanism underlying the effects of baicalein consists of inhibition of HIF-1α-mediated aerobic glycolysis and mitochondrial dysfunction.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Flavanonas/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Tamoxifeno/farmacologia , Efeito Warburg em Oncologia/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Resistência a Medicamentos/efeitos dos fármacos , Feminino , Flavanonas/metabolismo , Flavanonas/uso terapêutico , Subunidade alfa do Fator 1 Induzível por Hipóxia/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/uso terapêutico , Camundongos Endogâmicos NOD/metabolismo , Doenças Mitocondriais/tratamento farmacológico , Doenças Mitocondriais/fisiopatologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/estatística & dados numéricos , Tamoxifeno/metabolismo , Tamoxifeno/uso terapêutico
11.
Sci Rep ; 11(1): 16120, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34373487

RESUMO

Effects of combination therapy of dipeptidyl peptidase-4 (DPP-4) inhibitor and sodium-glucose co-transporter 2 (SGLT2) inhibitor on ß-cells are still unclear, although combination agent of these two drugs has become common in clinical practice. Therefore, we aimed to elucidate the effects of DPP-4 inhibitor and/or SGLT2 inhibitor on ß-cell mass and function and compared their effects between in an early and advanced phase of diabetes. We used 7-week-old db/db mice as an early phase and 16-week-old mice as an advanced phase and treated them for 2 weeks with oral administration of linagliptin, empagliflozin, linagliptin + empagliflozin (L + E group), and 0.5% carboxymethylcellulose (Cont group). Blood glucose levels in Empa and L + E group were significantly lower than Cont group after treatment. In addition, ß-cell mass in L + E group was significantly larger than Cont group only in an early phase, accompanied by increased Ki67-positive ß-cell ratio. In isolated islets, mRNA expression levels of insulin and its transcription factors were all significantly higher only in L + E group in an early phase. Furthermore, mRNA expression levels related to ß-cell differentiation and proliferation were significantly increased only in L + E group in an early phase. In conclusion, combination of DPP-4 inhibitor and SGLT2 inhibitor exerts more beneficial effects on ß-cell mass and function, especially in an early phase of diabetes rather than an advanced phase.


Assuntos
Compostos Benzidrílicos/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Linagliptina/farmacologia , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Inibidores da Dipeptidil Peptidase IV/farmacologia , Modelos Animais de Doenças , Combinação de Medicamentos , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos NOD/metabolismo , Camundongos Endogâmicos , Transportador 2 de Glucose-Sódio/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia
12.
Biosci Rep ; 40(1)2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31829413

RESUMO

Inflammatory response is closely related with the development of many serious health problems worldwide including diabetes mellitus (DM). Ubiquitin-fold modifer 1 (Ufm1) is a newly discovered ubiquitin-like protein, while its function remains poorly investigated, especially in inflammatory response and DM. In the present study, we analyzed the role of Ufm1 on inflammatory response in DM, and found that the proinflammatory cytokine levels (tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-1ß) and Ufm1 expression were highly increased both in the peritoneal macrophages of db/db mice and Raw264.7 cells induced by lipopolysaccharide (LPS). Western blot and luciferase reporter assay showed that NF-κB pathway was obviously activated in macrophages and the expression of LZAP, an inhibitor of NF-κB pathway, was down-regulated. With the LZAP knockdown plasmid and activation plasmid, we demonstrated that NF-κB/p65 activation was inhibited by LZAP in macrophages. The interaction of Ufm1 and LZAP was further proved with co-immunoprecipitation assay in HEK293 and Raw264.7 cells. The LZAP expression was also related with the presence of Ufm1 demonstrated by Ufm1 knockdown plasmid and activation plasmid. Besides that, we finally proved that the expression and activation of Ufm1 induced by LPS were regulated by JNK/ATF2 and JNK/c-Jun pathway with the use of SP600125. In conclusion, the present study demonstrated that Ufm 1 could activate NF-κB pathway by down-regulating LZAP in macrophage of diabetes, and its expression and activation were regulated by JNK/ATF2 and c-Jun pathway.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Diabetes Mellitus/metabolismo , Regulação para Baixo/fisiologia , Macrófagos Peritoneais/metabolismo , NF-kappa B/metabolismo , Proteínas/metabolismo , Transdução de Sinais/fisiologia , Animais , Linhagem Celular , Modelos Animais de Doenças , Células HEK293 , Humanos , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD/metabolismo , Células RAW 264.7 , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ubiquitinas/metabolismo
13.
Mol Immunol ; 114: 289-298, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31419705

RESUMO

Programmed cell death 1 ligand 1 (PD-L1) plays a critical role in mediating autoimmune diseases, including type I diabetes (T1D). B cells are important antigen-presenting cells (APCs) that make a major contribution to T1D development. However, B cells expressing low levels of PD-L1 that infiltrate insulitic islets in NOD mice may not inhibit effector T cells and prevent T1D. Here, we generated PD-L1 transgenic NOD (NOD.PD-L1Tg) mice, in which most immune cells overexpress PD-L1, to investigate the ability of B cells overexpressing PD-L1 to inhibit diabetic CD4+ T cells and prevent T1D. The severity of insulitis in NOD.PD-L1Tg mice was significantly lower than in NOD mice and none developed diabetes. In addition, there were no differences in expression of activity markers by APCs following LPS stimulation between two groups. In vitro studies revealed that B cells expressing high levels of PD-L1 inhibited proliferation of and cytokine secretion by pre-diabetic CD4+ T cells, whereas in vivo studies showed that NOD/SCID mice receiving diabetic CD4+ T cells mixed with B cells overexpressing PD-L1 became diabetic at a slower rate. Thus, we propose that B cells showing high expression of PD-L1 protect NOD mice against T1D and downregulate diabetogenic CD4+ T cells.


Assuntos
Linfócitos B/metabolismo , Antígeno B7-H1/metabolismo , Diabetes Mellitus Experimental/metabolismo , Camundongos Endogâmicos NOD/metabolismo , Animais , Doenças Autoimunes/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Regulação para Baixo/fisiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Estado Pré-Diabético/metabolismo
14.
Antioxid Redox Signal ; 28(5): 358-370, 2018 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-28683566

RESUMO

AIMS: Inhibition of microRNA-92a (miR-92a) is reported to suppress endothelial inflammation and delay atherogenesis. We hypothesize that miR-92a inhibition protects endothelial function through suppressing oxidative stress in diabetic db/db mice. RESULTS: In this study, we found elevated expression of miR-92a in aortic endothelium from db/db mice and in renal arteries from diabetic subjects. Endothelial cells (ECs) exposed to advanced glycation end products (AGEs) and oxidized low-density lipoprotein express higher level of miR-92a. Overexpression of miR-92a impairs endothelium-dependent relaxations (EDRs) in C57BL/6 mouse aortas. Overexpression of miR-92a suppresses expression of heme oxygenase-1 (HO-1), a critical cytoprotective enzyme, whereas inhibition of miR-92a increases HO-1 expression in human umbilical vein ECs (HUVECs) and db/db mouse aortas. Importantly, miR-92a inhibition by Ad-anti-miR-92a improved EDRs and reduced reactive oxygen species (ROS) production in db/db mouse aortas. HO-1 inhibition by SnMP or HO-1 knockdown by shHO-1 reversed the suppressive effect of miR-92a inhibition on ROS production induced by AGE treatment in C57BL/6 mouse aortas. In addition, SnMP reversed miR-92a inhibition-induced improvement of EDRs in AGE-treated C57BL/6 mouse aortas and in db/db mouse aortas. INNOVATION: Expression of miR-92a is increased in diabetic aortic endothelium and inhibition of miR-92a exerts vasoprotective effect in diabetic mice through HO-1 upregulation in ECs. CONCLUSION: MiR-92a expression is elevated in diabetic ECs. MiR-92a overexpression impairs endothelial function and suppresses HO-1 expression in ECs. Inhibition of miR-92a attenuates oxidative stress and improves endothelial function through enhancing HO-1 expression and activity in db/db mouse aortas. Antioxid. Redox Signal. 28, 358-370.


Assuntos
Aterosclerose/genética , Heme Oxigenase-1/genética , MicroRNAs/genética , Estresse Oxidativo/genética , Animais , Aorta/metabolismo , Aorta/patologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Regulação da Expressão Gênica/genética , Produtos Finais de Glicação Avançada/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Lipoproteínas LDL/genética , Lipoproteínas LDL/metabolismo , Camundongos , Camundongos Endogâmicos NOD/genética , Camundongos Endogâmicos NOD/metabolismo , MicroRNAs/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo
15.
Biomed Res Int ; 2017: 7651815, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28503574

RESUMO

Background/Aims. The effects of cholecalciferol supplementation on the course of diabetes in humans and animals need to be better understood. Therefore, this study investigated the effect of short-term cholecalciferol supplementation on biochemical and hematological parameters in mice. Methods. Male diabetic (alloxan, 60 mg/kg i.v., 10 days) and nondiabetic mice were supplemented with cholecalciferol for seven days. The following parameters were determined: serum levels of 25-hydroxyvitamin D, phosphorus, calcium, urea, creatinine, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, red blood cell count, white blood cell count (WBC), hematocrit, hemoglobin, differential cell counts of peritoneal lavage (PeL), and bronchoalveolar lavage (BAL) fluids and morphological analysis of lung, kidney, and liver tissues. Results. Relative to controls, cholecalciferol supplementation increased serum levels of 25-hydroxyvitamin D, calcium, hemoglobin, hematocrit, and red blood cell counts and decreased leukocyte cell counts of PeL and BAL fluids in diabetic mice. Diabetic mice that were not treated with cholecalciferol had lower serum calcium and albumin levels and hemoglobin, WBC, and mononuclear blood cell counts and higher serum creatinine and urea levels than controls. Conclusion. Our results suggest that cholecalciferol supplementation improves the hematological parameters and reduces leukocyte migration into the PeL and BAL lavage of diabetic mice.


Assuntos
Colecalciferol/administração & dosagem , Diabetes Mellitus Experimental/dietoterapia , Suplementos Nutricionais , Vitamina D/metabolismo , Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Movimento Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/patologia , Contagem de Eritrócitos , Humanos , Contagem de Leucócitos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos NOD/metabolismo , Cavidade Peritoneal/patologia , Vitamina D/análogos & derivados , Vitamina D/sangue
16.
Biosci Rep ; 37(5)2017 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-28931726

RESUMO

Diabetic gastroparesis is a common complication of diabetes mellitus (DM) that is characterized by decreased serum insulin and insulin-like growth factor-1 (IGF-1). Despite the fact that insulin treatment not glycemic control potently accelerated gastric emptying in type 1 DM patients, the role of insulin/InsR and IGF-1/IGF-1R signaling in diabetic gastroparesis remains incompletely elucidated. In the present study, type 1 DM mice were established and treated with insulin or Voglibose for 8 weeks. The gastric emptying was delayed from DM week 4 when the gastric InsR and IGF-1R were declined. Meanwhile, the gastric choline acetyltransferase (ChAT) was significantly reduced and the myenteric cholinergic neurones and their fibers were significantly diminished. The production of stem cell factor (SCF) was dramatically repressed in the gastric smooth muscles in DM week 6. TWereafter, interstitial cells of Cajal (ICC) were clearly lost and their networks were impaired in DM week 8. Significantly, compared with Voglibose, an 8-week treatment with insulin more efficiently delayed diabetic gastroparesis development by protecting the myenteric cholinergic neurones and ICC. In conclusion, diabetic gastroparesis was an aggressive process due to the successive damages of myenteric cholinergic neurones and ICC by impairing the insulin/InsR and IGF-1/IGF-1R signaling. Insulin therapy in the early stage may delay diabetic gastroparesis.


Assuntos
Antígenos CD/genética , Complicações do Diabetes/genética , Gastroparesia/genética , Fator de Crescimento Insulin-Like I/genética , Insulina/administração & dosagem , Receptor IGF Tipo 1/genética , Receptor de Insulina/genética , Animais , Antígenos CD/metabolismo , Colina O-Acetiltransferase/genética , Neurônios Colinérgicos/metabolismo , Neurônios Colinérgicos/patologia , Complicações do Diabetes/tratamento farmacológico , Complicações do Diabetes/metabolismo , Complicações do Diabetes/patologia , Modelos Animais de Doenças , Gastroparesia/tratamento farmacológico , Gastroparesia/metabolismo , Gastroparesia/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inositol/administração & dosagem , Inositol/análogos & derivados , Insulina/genética , Fator de Crescimento Insulin-Like I/metabolismo , Células Intersticiais de Cajal/metabolismo , Células Intersticiais de Cajal/patologia , Camundongos , Camundongos Endogâmicos NOD/genética , Camundongos Endogâmicos NOD/metabolismo , Músculo Liso/metabolismo , Músculo Liso/patologia , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/metabolismo , Fator de Células-Tronco/genética
17.
Autoimmunity ; 39(8): 645-50, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17178561

RESUMO

The non-obese diabetic (NOD) mouse is a widely used animal model for study of autoimmune diseases, in particular human type 1 diabetes mellitus (T1DM). Identification of the subset of peptides that bind MHC molecules comprising the H-2g7 haplotype of NOD mouse and thereby representing potential NOD T-cell epitopes is important for research into the pathogenesis and immunotherapy of T1DM. The H-2g7 haplotype comprises the MHC class-I molecules Kd and Db and a single class-II molecule I-Ag7. We have developed a prediction system, PREDNOD, for accurate identification of peptides that bind the MHC molecules constituting the H-2g7 haplotype. PREDNOD is accessible at http://antigen.i2r.a-star.edu.sg/Ag7.


Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Antígenos H-2/metabolismo , Camundongos Endogâmicos NOD/metabolismo , Modelos Imunológicos , Software , Algoritmos , Sequência de Aminoácidos , Animais , Diabetes Mellitus Tipo 1/imunologia , Epitopos de Linfócito T/imunologia , Antígenos H-2/imunologia , Haplótipos , Camundongos , Camundongos Endogâmicos NOD/imunologia , Dados de Sequência Molecular , Peptídeos , Valor Preditivo dos Testes , Ligação Proteica
18.
PLoS One ; 11(11): e0166215, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27846299

RESUMO

Diabetes causes skin complications, including xerosis and foot ulcers. Ulcers complicated by infections exacerbate skin conditions, and in severe cases, limb/toe amputations are required to prevent the development of sepsis. Here, we hypothesize that hyperglycemia induces skin barrier dysfunction with alterations of epidermal integrity. The effects of hyperglycemia on the epidermis were examined in streptozotocin-induced diabetic mice with/without insulin therapy. The results showed that dye leakages were prominent, and transepidermal water loss after tape stripping was exacerbated in diabetic mice. These data indicate that hyperglycemia impaired skin barrier functions. Additionally, the distribution of the protein associated with the tight junction structure, tight junction protein-1 (ZO-1), was characterized by diffuse and significantly wider expression in the diabetic mice compared to that in the control mice. In turn, epidermal cell number was significantly reduced and basal cells were irregularly aligned with ultrastructural alterations in diabetic mice. In contrast, the number of corneocytes, namely, denucleated and terminally differentiated keratinocytes significantly increased, while their sensitivity to mechanical stress was enhanced in the diabetic mice. We found that cell proliferation was significantly decreased, while apoptotic cells were comparable in the skin of diabetic mice, compared to those in the control mice. In the epidermis, Keratin 5 and keratin 14 expressions were reduced, while keratin 10 and loricrin were ectopically induced in diabetic mice. These data suggest that hyperglycemia altered keratinocyte proliferation/differentiation. Finally, these phenotypes observed in diabetic mice were mitigated by insulin treatment. Reduction in basal cell number and perturbation of the proliferation/differentiation process could be the underlying mechanisms for impaired skin barrier functions in diabetic mice.


Assuntos
Proliferação de Células/genética , Diabetes Mellitus Tipo 1/metabolismo , Hiperglicemia/metabolismo , Pele/metabolismo , Animais , Apoptose/genética , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Proliferação de Células/efeitos dos fármacos , Diabetes Mellitus Tipo 1/patologia , Epiderme/metabolismo , Epiderme/patologia , Epiderme/ultraestrutura , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hiperglicemia/patologia , Insulina/administração & dosagem , Insulina/metabolismo , Queratina-10/biossíntese , Queratina-10/genética , Queratina-14/biossíntese , Queratina-14/genética , Queratina-5/biossíntese , Queratina-5/genética , Queratinócitos/metabolismo , Queratinócitos/patologia , Queratinócitos/ultraestrutura , Proteínas de Membrana/biossíntese , Camundongos , Camundongos Endogâmicos NOD/metabolismo , Pele/patologia , Pele/ultraestrutura , Proteína da Zônula de Oclusão-1/biossíntese , Proteína da Zônula de Oclusão-1/genética
19.
Diabetes ; 48(8): 1638-44, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10426384

RESUMO

Nonobese diabetic (NOD) mice develop glomerulosclerosis shortly after the onset of diabetes. We showed that mesangial cells (MCs) from diabetic mice exhibited a stable phenotypic switch, consisting of both increased IGF-1 synthesis and proliferation (Elliot SJ, Striker LJ, Hattori M, Yang CW, He CJ, Peten EP, Striker GE: Mesangial cells from diabetic NOD mice constitutively secrete increased amounts of insulin-like growth factor-I. Endocrinology 133:1783-1788, 1993). Because the extracellular matrix (ECM) accumulation in diabetic glomerulosclerosis may be partly due to decreased degradation, we examined the effect of excess IGF-1 on collagen turnover and the activity of metalloproteinases (MMPs) and tissue inhibitors of metalloproteinase (TIMPs) in diabetic and nondiabetic NOD-MC. Total collagen degradation was reduced by 58 +/- 18% in diabetic NOD-MCs, which correlated with a constitutive decrease in MMP-2 activity and mRNA levels, and nearly undetectable MMP-9 activity and mRNA. TIMP levels were slightly decreased in diabetic NOD-MC. The addition of recombinant IGF-1 to nondiabetic NOD-MC resulted in a decrease in MMP-2 and TIMP activity. Furthermore, treatment of diabetic NOD-MC with a neutralizing antibody against IGF-1 increased the latent form, and restored the active form, of MMP-2. In conclusion, the excessive production of IGF-1 contributes to the altered ECM turnover in diabetic NOD-MC, largely through a reduction of MMP-2 activity. These data suggest that IGF-1 could be a major contributor to the development of diabetic glomerulosclerosis.


Assuntos
Colágeno/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Mesângio Glomerular/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Camundongos Endogâmicos NOD/metabolismo , Animais , Células Cultivadas , Colágeno/biossíntese , Colágeno/genética , Colagenases/genética , Colagenases/metabolismo , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/etiologia , Feminino , Gelatinases/genética , Gelatinases/metabolismo , Mesângio Glomerular/patologia , Glomerulosclerose Segmentar e Focal/etiologia , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Laminina/genética , Metaloproteinase 2 da Matriz , Metaloproteinase 9 da Matriz , Metaloendopeptidases/genética , Metaloendopeptidases/metabolismo , Camundongos , Camundongos Endogâmicos NOD/genética , RNA Mensageiro/metabolismo , Inibidores Teciduais de Metaloproteinases/metabolismo
20.
Endocrinology ; 130(1): 37-42, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1727711

RESUMO

Recent observations have shown that the presumed target antigen of cytoplasmic islet cell antibodies (ICA) has properties of a monosialo-ganglioside migrating between GM2 and GM1 standards (GM2-1) and that ICA binding is higher in nonobese diabetic (NOD) than in C57BL/10SnJ mouse pancreatic frozen sections. This study aimed to characterize the ganglioside expression in NOD mouse islets in comparison with the control C57BL/10SnJ strain, taking into account possible sex differences, variations with age, and changes after autoimmune beta-cell destruction. Thus, acidic glycolipid composition was analyzed 1) in isolated islets from 11-week-old female and male NOD mice and age-matched female and male C57BL/10SnJ mice, and 2) in whole pancreas of both NOD and control mouse strains at different ages (4, 8, and 18 weeks) and of female NOD mice before and after diabetes onset. The acidic glycolipid GM2-1 is expressed in isolated female NOD islets, male NOD islets, and C57BL/10SnJ mouse islets, but quantitative analysis showed an increased amount of GM2-1 in NOD vs. C57BL/10 islets. GM3 is a ganglioside fraction expressed in female and male NOD mice and not in the C57BL/10 strain, whereas GD3 characterizes the C57BL/10 strain islets. GM2-1 is the sole ganglioside fraction in the whole pancreas to clearly decrease with age in the NOD mouse, and diabetes onset in this strain is associated with a significant decrease in the expression of this component as well as of GM3, whereas other pancreatic ganglioside (GD3, GD1a, and GT1b) levels did not significantly decrease; no age-related ganglioside change was observed in the C57BL/10SnJ mouse. Interestingly, the observed increased ICA binding in NOD islets is paralleled by the increased expression of GM2-1 islet ganglioside, and beta-cell destruction in NOD mice is associated with a significant decrease in the amount of this ganglioside in the pancreas.


Assuntos
Autoimunidade , Diabetes Mellitus Tipo 1/metabolismo , Gangliosídeos/análise , Ilhotas Pancreáticas/química , Camundongos Endogâmicos NOD/metabolismo , Fatores Etários , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Feminino , Ilhotas Pancreáticas/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pâncreas/química , Fatores Sexuais
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