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1.
Biochim Biophys Acta Mol Basis Dis ; 1870(5): 167065, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38342419

RESUMO

Transcription factor EB (TFEB), a master lysosomal biogenesis and autophagy regulator, is crucial for cellular homeostasis, and its abnormality is related to diverse inflammatory diseases. Genetic variations in autophagic genes are associated with susceptibility to inflammatory bowel disease (IBD); however, little is known about the role and mechanism of TFEB in disease pathogenesis. In this study, we found that the genetic deletion of TFEB in mouse intestinal epithelial cells (IEC) caused intestinal barrier dysfunction, leading to increased susceptibility to experimental colitis. Mechanistically, TFEB functionally protected IEC in part through peroxisome proliferator-activated receptor gamma coactivator 1alpha (TFEB-PGC1α axis) induction, which consequently suppressed reactive oxygen species. TFEB can directly regulate PGC-1α transcription to control antioxidation level. Notably, TFEB expression is impaired and downregulated in the colon tissues of IBD patients. Collectively, our results indicate that intestinal TFEB participates in oxidative stress regulation and attenuates IBD progression.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Homeostase , Doenças Inflamatórias Intestinais , Mucosa Intestinal , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Espécies Reativas de Oxigênio , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Animais , Espécies Reativas de Oxigênio/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Doenças Inflamatórias Intestinais/genética , Camundongos , Humanos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Estresse Oxidativo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Masculino , Colite/metabolismo , Colite/patologia , Colite/induzido quimicamente , Colite/genética
2.
Front Endocrinol (Lausanne) ; 14: 1170237, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37305058

RESUMO

Diabetes mellitus (DM) is a systemic metabolic disease with high mortality and morbidity. Extracellular vesicles (EVs) have emerged as a novel class of signaling molecules, biomarkers and therapeutic agents. EVs-mediated intercellular and interorgan crosstalk of pancreatic islets plays a crucial role in the regulation of insulin secretion of ß-cells and insulin action in peripheral insulin target tissues, maintaining glucose homeostasis under physiological conditions, and it's also involved in pathological changes including autoimmune response, insulin resistance and ß-cell failure associated with DM. In addition, EVs may serve as biomarkers and therapeutic agents that respectively reflect the status and improve function and viability of pancreatic islets. In this review, we provide an overview of EVs, discuss EVs-mediated intercellular and interorgan crosstalk of pancreatic islet under physiological and diabetic conditions, and summarize the emerging applications of EVs in the diagnosis and treatment of DM. A better understanding of EVs-mediated intercellular and interorgan communication of pancreatic islets will broaden and enrich our knowledge of physiological homeostasis maintenance as well as the development, diagnosis and treatment of DM.


Assuntos
Diabetes Mellitus , Vesículas Extracelulares , Ilhotas Pancreáticas , Humanos , Fenômenos Fisiológicos Celulares , Insulina
4.
Adv Healthc Mater ; 11(21): e2200782, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36101484

RESUMO

Impaired diabetic wound healing is associated with the persistence of chronic inflammation and excessive oxidative stress, which has become one of the most serious clinical challenges. Wound dressings with anti-inflammatory and reactive oxygen species (ROS)-scavenging properties are desirable for diabetic wound treatment. In this study, a shape-adaptable, biodegradable, biocompatible, antioxidant, and immunomodulatory interleukin-33 (IL-33)-cytogel is developed by encapsulating IL-33 into physically cross-linked DNA hydrogels and used as wound dressings to promote diabetic wound healing. The porous microstructures and biodegradable properties of the IL-33-cytogel ensure the local sustained-release of IL-33 in the wound area, where the sustained-release of IL-33 is maintained for at least 7 days. IL-33-cytogel can induce local accumulation of group 2 innate lymphoid cells (ILC2s) and regulatory T cells (Tregs), as well as M1-to-M2 transition at the wound sites. Additionally, the antioxidant and biocompatible characteristics of DNA hydrogels promote the scavenging of intracellular ROS without affecting cell viability. As a result, local inflammation in the diabetic wound area is resolved upon IL-33-cytogel treatment, which is accompanied by improved granulation tissue regeneration and accelerated wound closure. This study demonstrates a promising strategy in tissue engineering and regenerative medicine by incorporating DNA hydrogels and cytokine immunotherapy for promoting diabetic wound healing.


Assuntos
Diabetes Mellitus , Hidrogéis , Humanos , Hidrogéis/química , Antioxidantes , Interleucina-33 , Imunidade Inata , Preparações de Ação Retardada , Espécies Reativas de Oxigênio , Citocinas , Linfócitos , Cicatrização , Inflamação , DNA
5.
J Cell Mol Med ; 26(18): 4847-4858, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35975481

RESUMO

Significant pancreatic islet dysfunction and loss shortly after transplantation to the liver limit the widespread implementation of this procedure in the clinic. Nonimmune factors such as reactive oxygen species and inflammation have been considered as the primary driving force for graft failure. The adipokine adiponectin plays potent roles against inflammation and oxidative stress. Previous studies have demonstrated that systemic administration of adiponectin significantly prevented islet loss and enhanced islet function at post-transplantation period. In vitro studies indicate that adiponectin protects islets from hypoxia/reoxygenation injury, oxidative stress as well as TNF-α-induced injury. By applying adenovirus mediated transfection, we now engineered islet cells to express exogenous adiponectin gene prior to islet transplantation. Adenovirus-mediated adiponectin transfer to a syngeneic suboptimal islet graft transplanted under kidney capsule markedly prevented inflammation, preserved islet graft mass and improved islet transplant outcomes. These results suggest that adenovirus-mediated adiponectin gene therapy would be a beneficial clinical engineering approach for islet preservation in islet transplantation.


Assuntos
Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Adenoviridae/genética , Adiponectina/genética , Terapia Genética , Sobrevivência de Enxerto , Humanos , Inflamação , Transplante das Ilhotas Pancreáticas/métodos
6.
Nutrients ; 14(10)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35631254

RESUMO

Emerging research indicates that vitamin D metabolic disorder plays a major role in both acute pancreatitis (AP) and chronic pancreatitis (CP). This has been demonstrated by studies showing that vitamin D deficiency is associated with pancreatitis and its anti-inflammatory and anti-fibrotic effects by binding with the vitamin D receptor (VDR). However, the role of vitamin D assessment and its management in pancreatitis remains poorly understood. In this narrative review, we discuss the recent advances in our understanding of the molecular mechanisms involved in vitamin D/VDR signaling in pancreatic cells; the evidence from observational studies and clinical trials that demonstrate the connection among vitamin D, pancreatitis and pancreatitis-related complications; and the route of administration of vitamin D supplementation in clinical practice. Although further research is still required to establish the protective role of vitamin D and its application in disease, evaluation of vitamin D levels and its supplementation should be important strategies for pancreatitis management according to currently available evidence.


Assuntos
Pancreatite , Deficiência de Vitamina D , Doença Aguda , Humanos , Pancreatite/complicações , Pancreatite/etiologia , Vitamina D/uso terapêutico , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/tratamento farmacológico , Vitaminas/uso terapêutico
7.
ACS Appl Mater Interfaces ; 14(22): 25173-25182, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35638566

RESUMO

The development of a biodegradable and shape-adaptable bioscaffold that can enhance local cytokine retention and bioactivity is essential for the application of immunotherapy in periodontal diseases. Here, we report a biodegradable, anti-inflammatory, and osteogenic ILGel that uses a physically cross-linked DNA hydrogel as a soft bioscaffold for the long-term sustained release of cytokine interleukin-10 (IL-10) to accelerate diabetic alveolar bone rebuilding. Porous microstructures of ILGel favored the encapsulation of IL-10 and maintained IL-10 bioactivity for at least 7 days. ILGel can be gradually degraded or hydrolyzed under physiological conditions, avoiding the potential undesired side effects on dental tissues. Long-term sustained release of bioactive IL-10 from ILGel not only promoted M2 macrophage polarization and attenuated periodontal inflammation but also triggered osteogenesis of mesenchymal stem cells (MSCs), leading to accelerated alveolar bone formation and healing of alveolar bone defects under diabetic conditions in vivo. ILGel treatment significantly accelerated the defect healing rate of diabetic alveolar injury up to 93.42 ± 4.6% on day 21 post treatment compared to that of free IL-10 treatment (63.30 ± 7.39%), with improved trabecular architectures. Our findings imply the potential application of the DNA hydrogel as the bioscaffold for cytokine-based immunotherapy in diabetic alveolar bone injury and other periodontal diseases.


Assuntos
Diabetes Mellitus , Doenças Periodontais , Regeneração Óssea , Citocinas , DNA , Preparações de Ação Retardada , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Interleucina-10 , Osteogênese/genética
8.
Am J Physiol Gastrointest Liver Physiol ; 323(2): G102-G113, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35638642

RESUMO

Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), are intestinal complications characterized by chronic inflammation, autophagy abnormality, and lysosomal stress, which are derived from genetic predisposition and environmental risk factors. It is generally precepted that dietary green vegetable is beneficial for physiological homeostasis. In this study, we found that dextran sulfate sodium (DSS)-induced colitis and altered intestinal epithelia in mice were attenuated by oral administration of chlorophyllin (CHL), a water-soluble derivate of chlorophyll. In DSS-treated mice, autophagy was persistently activated in intestinal tissues and associated with bowel disorders. Conversely, supplement of CHL in diet or gavage suppressed intestinal inflammation, downregulated autophagy flux in intestinal tissue, and relieved endoplasmic reticulum stress. In vitro studies show that CHL could activate Akt and mTOR pathways, leading to downregulation of autophagic and lysosomal flux. Thus, consumption of green vegetables and chlorophyllin may be beneficial for IBD recovery in part through alleviation of inflammation and autolysosomal flux.NEW & NOTEWORTHY Inflammatory bowel disease (IBD) is a chronic and recurrent gastrointestinal disease, while the etiology remains poorly understood. Dietary composition and lifestyle are crucial for pathogenesis and progression of IBD. In this study, we observed that autophagy in the intestinal tissue was persistently activated in IBD mice. Chlorophyllin (CHL), a water-soluble derivate of chlorophyll, can attenuate colitis by regulating autophagy and inflammation. Thus, consumption of green vegetables and chlorophyllin may be beneficial for IBD recovery.


Assuntos
Clorofilídeos , Colite , Doenças Inflamatórias Intestinais , Animais , Autofagia , Clorofilídeos/efeitos adversos , Colite/induzido quimicamente , Colite/tratamento farmacológico , Sulfato de Dextrana , Inflamação , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Água
9.
Front Physiol ; 13: 854545, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35600308

RESUMO

Objective: The gut microbiota and its metabolites are important for host physiological homeostasis, while dysbiosis is related to diseases including the development of cancers such as colorectal cancer (CRC). In this study, we characterized the relationship of an altered gut microbiome with the fecal metabolome in CRC patients in comparison with volunteers having a normal colorectal mucous membrane (NC). Methods: The richness and composition of the microbiota in fecal samples of 30 CRC patients and 36 NC controls were analyzed through 16S rRNA gene sequencing, and the metabolome was determined by ultra-performance liquid chromatography coupled to tandem mass spectrometry. Spearman correlation analysis was to determine the correlation between the gut microbiome and fecal metabolome in CRC patients. Results: There were significant alterations in the gut microbiome and fecal metabolome in CRC patients compared with NC controls. Bacteroidetes, Firmicutes, Actinobacteriota, and Proteobacteria dominated the gut microbial communities at the phylum level in both groups. Compared with NC controls, CRC patients had a lower frequency of Blautia and Lachnospiracaea but a higher abundance of Bacteroides fragilis and Prevotella. Regarding the fecal metabolome, twenty-nine metabolites were identified as having significantly changed, showing increased levels of adrenic acid, decanoic acid, arachidonic acid, and tryptophan but a reduction in various monosaccharides in the fecal samples of CRC patients. Moreover, increased abundance of Bacteroides fragilis was strongly associated with decreased levels of monosaccharides, while Blautia was positively associated with the production of monosaccharides in the fecal samples. Conclusion: These results highlight alterations of gut microbiota in association with certain metabolites in CRC progression, implying potential diagnostic and intervention potential for CRC.

10.
Front Microbiol ; 13: 834335, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35479628

RESUMO

Tibetans are one of the oldest ethnic groups in China and South Asia. Based on the analysis of 1,059 Tibetans in the Minjiang River basin at an altitude of 500-4,001 m, we found that the dominant phyla of the Tibetan population were Bacteroidota and Firmicutes, and the main genera were Prevotella and Bacteroides, which were mostly in consistent with other nationalities. We further evaluated in total 115 parameters of seven categories, and results showed that altitude was the most important factor affecting the variation in the microbial community. In the process of emigration from high altitudes to the plain, the gut microbial composition of late emigrants was similar to that of plateau aborigines. In addition, regarding immigration from low altitude to high altitude, the microbial community became more similar to that of high altitude population with the increase of immigration time. Changes in these microbes are related to the metabolism, disease incidence and cell functions of the Tibetan population. The results of other two cohorts (AGP and Z208) also showed the impact of altitude on the microbial community. Our study demonstrated that altitude of habitation is an important factor affecting the enterotype of the microflora in the Tibetan population and the study also provided a basis to explore the interaction of impact parameters with gut microbiome for host health and diseases.

11.
Cancers (Basel) ; 14(6)2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35326559

RESUMO

Pancreatic cancer is driven by risk factors such as diabetes and chronic pancreatic injury, which are further associated with gut dysbiosis. Intestinal toxins such as bile acids and bacterial endotoxin (LPS), in excess and persistence, can provoke chronic inflammation and tumorigenesis. Of interest is that many intestinal toxins are negatively charged acidic components in essence, which prompted us to test whether oral administration of cationic resin can deplete intestinal toxins and ameliorate pancreatic cancer. Here, we found that increased plasma levels of endotoxin and bile acids in Pdx1-Cre: LSL-KrasG12D/+ mice were associated with the transformation of the pancreatic ductal carcinoma (PDAC) state. Common bile-duct-ligation or LPS injection impeded autolysosomal flux, leading to Yap accumulation and malignant transformation. Conversely, oral administration of cholestyramine to sequestrate intestinal endotoxin and bile acids resumed autolysosomal flux for Yap degradation and attenuated metastatic incidence. Conversely, chloroquine treatment impaired autolysosomal flux and exacerbated malignance, showing jeopardization of p62/ Sqxtm1 turnover, leading to Yap accumulation, which is also consistent with overexpression of cystatin A (CSTA) in situ with pancreatic cancer cells and metastatic tumor. At cellular levels, chenodeoxycholic acid or LPS treatment activated the ligand-receptor-mediated AKT-mTOR pathway, resulting in autophagy-lysosomal stress for YAP accumulation and cellular dissemination. Thus, this work indicates a potential new strategy for intervention of pancreatic metastasis through sequestration of intestinal acidic toxins by oral administration of cationic resins.

13.
Comput Struct Biotechnol J ; 19: 6375-6385, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34938413

RESUMO

Chronic pancreatitis (CP) is characterized by irreversible fibro-inflammatory changes induced by pancreatic stellate cell (PSC). Unresolved or recurrent injury causes dysregulation of biological process following AP, which would cause CP. Here, we systematically identify genes whose expressions are unique to PSC by comparing transcriptome profiles among total pancreas, pancreatic stellate, acinar, islet and immune cells. We then identified candidate genes and correlated them with the pancreatic disease continuum by performing intersection analysis among total PSC and activated PSC genes, and genes persistently differentially expressed during acute pancreatitis (AP) recovery. Last, we examined the association between candidate genes and AP, and substantiated their potential as biomarkers in experimental AP and recurrent AP (RAP) models. A total of 68 genes were identified as highly and uniquely expressed in PSC. The PSC signatures were highly enriched with extracellular matrix remodeling genes and were significantly enriched in AP pancreas compared to healthy control tissues. Among PSC signature genes that comprised a fibrotic phenotype, 10 were persistently differentially expressed during AP recovery. SPARC was determined as a candidate marker for the pancreatic disease continuum, which was not only persistently differentially expressed even five days after AP injury, but also highly expressed in two clinical datasets of CP. Sparc was also validated as highly elevated in RAP compared to AP mice. This work highlights the unique transcriptional profiles of PSC. These PSC signatures' expression may help to identify patients with high risk of AP progression to CP.

14.
Front Physiol ; 12: 739174, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34764881

RESUMO

Non-alcoholic fatty liver diseases (NAFLDs) along with metabolic syndrome and Type-2 diabetes (T2D) are increasingly prevalent worldwide. Without an effective resolution, simple hepatic steatosis may lead to non-alcoholic steatohepatitis (NASH), characterized by hepatocyte damage, chronic inflammation, necrosis, fatty degeneration, and cirrhosis. The gut microbiome is vital for metabolic homeostasis. Conversely, dysbiosis contributes to metabolic diseases including NAFLD. Specifically, diet composition is critical for the enterotype of gut microbiota. We reasoned that green pigment rich in vegetables may modulate the gut microbiome for metabolic homeostasis. In this study, C57BL/6 mice under a high fat diet (HFD) were treated with sodium copper chlorophyllin (CHL), a water-soluble derivative of chlorophyll, in drinking water. After 28 weeks of HFD feeding, liver steatosis was established accompanied by gut microbiota dysbiosis, intestinal impairment, endotoxemia, systemic inflammation, and insulin resistance. Administration of CHL effectively alleviated systemic and intestinal inflammation and maintained tight junction in the intestinal barrier. CHL rebalanced gut microbiota in the mice under high fat feeding and attenuated hepatic steatosis, insulin resistance, dyslipidemia, and reduced body weight. Fecal flora transplants from the CHL-treated mice ameliorated steatosis as well. Thus, dietary green pigment or the administration of CHL may maintain gut eubiosis and intestinal integrity to attenuate systemic inflammation and relieve NASH.

15.
ACS Nano ; 15(11): 18237-18249, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34723467

RESUMO

Cytokine immunotherapy represents an attractive strategy to stimulate robust immune responses for renal injury repair in ischemic acute kidney injury (AKI). However, its clinical application is hindered by its nonspecificity to kidney, short circulation half-life, and severe side effects. An ideal cytokine immunotherapy for AKI requires preferential delivery of cytokines with accurate dosage to the kidney and sustained-release of cytokines to stimulate the immune responses. Herein, we developed a DNA nanoraft cytokine by precisely arranging interleukin-33 (IL-33) nanoarray on rectangle DNA origami, through which IL-33 can be preferentially delivered to the kidney for alleviation of AKI. A nanoraft carrying precisely quantified IL-33 predominantly accumulated in the kidney for up to 48 h. Long-term sustained-release of IL-33 from nanoraft induced rapid expansion of type 2 innate lymphoid cells (ILC 2s) and regulatory T cells (Tregs) and achieved better treatment efficiency compared to free IL-33 treatment. Thus, our study demonstrates that a nanoraft can serve as a structurally well-defined delivery platform for cytokine immunotherapy in ischemic AKI and other renal diseases.


Assuntos
Injúria Renal Aguda , Citocinas , Sistemas de Liberação de Fármacos por Nanopartículas , Humanos , Injúria Renal Aguda/terapia , Preparações de Ação Retardada , Imunidade Inata , Interleucina-33 , Rim , Linfócitos , DNA/química
16.
Cancers (Basel) ; 13(5)2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33803301

RESUMO

Hepatitis B virus (HBV) infection is a major etiological risk for the incidence of hepatocellular carcinoma (HCC), and HBV X protein (HBx) is essential for oncogenic transformation. It is not known that if HBx can sabotage the lysosomal system for transformation and tumorigenesis, or its mechanism if it does have an effect. Examining clinical data, we observed that the downregulation of lysosomal components and transcription factor EB (TFEB) was associated with a poor prognosis of HCC patients. In HCC cells, we found that expression of HBx suppressed TFEB, impaired biogenesis of autophagic-lysosome, and promoted cellular dissemination. HBx mediated downregulation of TFEB led to impairment of autophagic/lysosomal biogenesis and flux, and consequently, accumulation of integrin beta 1 (ITGB1) for motility of HCC cells. Conversely, TFEB, in a steady-state condition, through induction of lysosomal biogenesis restrained ITGB1 levels and limited mobility of HCC cells. Specifically, overexpression of TFEB upregulated and activated the cysteine proteases including cathepsin L (CTSL) to degrade ITGB1. Conversely, expression of cystatin A (CSTA) or cystatin B (CSTB), the cellular inhibitors of lysosomal cysteine proteinases, spared ITGB1 from degradation and promoted dissemination of HCC cells. Taken together, this study suggests a potential mechanism for HBV-mediated malignancy, showing that HBx mediated downregulation of TFEB leads to accumulation of ITGB1 for HCC cell migration.

17.
Sci Rep ; 11(1): 6036, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33727603

RESUMO

Vertical sleeve gastrectomy (VSG) is one of the most commonly performed clinical bariatric surgeries for the remission of obesity and diabetes. Its effects include weight loss, improved insulin resistance, and the improvement of hepatic steatosis. Epidemiologic studies demonstrated that vitamin D deficiency (VDD) is associated with many diseases, including obesity. To explore the role of vitamin D in metabolic disorders for patients with obesity after VSG. We established a murine model of diet-induced obesity + VDD, and we performed VSGs to investigate VDD's effects on the improvement of metabolic disorders present in post-VSG obese mice. We observed that in HFD mice, the concentration of VitD3 is four fold of HFD + VDD one. In the post-VSG obese mice, VDD attenuated the improvements of hepatic steatosis, insulin resistance, intestinal inflammation and permeability, the maintenance of weight loss, the reduction of fat loss, and the restoration of intestinal flora that were weakened. Our results suggest that in post-VSG obese mice, maintaining a normal level of vitamin D plays an important role in maintaining the improvement of metabolic disorders.


Assuntos
Gastrectomia , Doenças Metabólicas , Obesidade , Deficiência de Vitamina D , Animais , Masculino , Doenças Metabólicas/metabolismo , Doenças Metabólicas/patologia , Doenças Metabólicas/cirurgia , Camundongos , Camundongos Obesos , Obesidade/metabolismo , Obesidade/patologia , Obesidade/cirurgia , Deficiência de Vitamina D/metabolismo , Deficiência de Vitamina D/patologia , Deficiência de Vitamina D/cirurgia
18.
Int J Mol Med ; 47(1): 267-275, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33236149

RESUMO

Sepsis­induced blood vessel dysfunction is mainly caused by microvascular endothelial cell injury. However, the mechanism underlying sepsis­induced endothelial cell injury remains unclear. The present study hypothesized that sepsis­induced inflammatory injury of endothelial cells may be the first step of endothelial barrier dysfunction. Therefore, the present study aimed to uncover the mechanism underlying the inflammatory effects of sepsis. A rat model of cecal ligation and puncture­induced sepsis was established, and septic serum was collected. Subsequently, human umbilical vein endothelial cells (HUVECs) were treated with the isolated septic or normal serum. HUVEC viability was assessed using a Cell Count Kit­8 assay. Furthermore, transmission electron microscopy and reverse transcription­quantitative PCR (RT­qPCR) analysis were carried out to observe the cell morphology and determine the mRNA expression levels in septic serum­induced HUVECs. The protein expression levels were evaluated by western blot analysis, and the secretion of the inflammatory factors interleukin (IL)­1ß, IL­6 and tumor necrosis factor (TNF)­α was determined by ELISA. Additionally, reactive oxygen species (ROS) generation and nuclear factor (NF)­κB nuclear translocation were observed under a fluorescence microscope. The results of the present study demonstrated that HUVEC viability was significantly decreased following 12­ or 24­h treatment with septic serum. In addition, chromatin condensation, mitochondrial vacuolization and endoplasmic reticulum degranulation were observed following treatment with septic serum. Furthermore, the secretion levels of IL­1ß, IL­6 and TNF­α were increased in septic serum­stimulated HUVECs. Septic serum treatment also enhanced superoxide anion generation, promoted extracellular signal regulated kinase 1/2 (ERK1/2), N­terminal kinase (JNK) and p38 mitogen­activated protein kinase (p38) phosphorylation, and increased NF­κB levels in the nuclei of HUVECs. Finally, pre­treatment of HUVECs with the antioxidant N­acetylcysteine, the ERK1/2 inhibitor PD98059, the p38 inhibitor SB203580, the JNK inhibitor SP610025 or the NF­κB inhibitor pyrrolidine dithiocarbamate restored the septic serum­induced IL­1ß, IL­6 and TNF­α expression. In conclusion, the results of the current study suggested that the septic serum­induced endothelial cell injury may be mediated by increasing ROS generation, activation of mitogen­activated protein kinases and NF­κB translocation.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Sistema de Sinalização das MAP Quinases , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sepse/metabolismo , Animais , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Inflamação/metabolismo , Inflamação/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Sepse/patologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-33084400

RESUMO

Vitamin D deficiency is co-prevalent with various liver diseases including cirrhosis, while the underlying mechanism remains elusive. Vitamin D receptor (VDR) is abundantly expressed in the distal region of small intestine, where the Paneth cells are enriched, suggesting that vitamin D signaling may modulates the intestinal Paneth cells and their production of defensins to restrain microbiome growth in the small intestine. In this study we found that in carbon tetrachloride-induced liver injury, hepatic 25-hydroxylation of vitamin D was impaired, leading to down regulated expression of Paneth cell fensins in the small intestine, gut dysbiosis, and endotoxinemia. While intraperitoneal injection of endotoxin (lipopolysaccharides) alone did not elicit liver fibrosis, it exacerbated the carbon tetrachloride initiated liver fibrogenesis. Oral gavage of synthetic Paneth cell alpha-defensin 5 (DEFA5) restored the homeostasis of gut microbiota, reduced endotoxemia, relieved liver inflammation, and ameliorated liver fibrosis. Likewise, Cholestyramine, cationic resin that can sequestrate endotoxin in the intestine, attenuated the liver fibrosis as well. Fecal transplant of the microbes derived from the DEFA5-treated donors improved liver fibrosis in the recipient mice. The intestinal Vdrconditional knockout mice exhibited reduction of Paneth cell defensins and lysozyme production, and worsened liver injury and fibrogenesis. Thus, liver injury impairs synthesis of 25(OH)VD3, which consequently impedes the Paneth cells functions in the small intestine, leading to gut dysbiosis for liver fibrogenesis.

20.
J Physiol Biochem ; 76(4): 587-598, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32875543

RESUMO

Chronic fructose consumption and vitamin D deficiency (VDD) diet have been linked to the pandemic of metabolic syndrome (MetS) and nonalcoholic fatty liver disease (NAFLD). The metabolic mechanisms remain unclear. This study is to explore metabolic changes of mice fed with high fructose syrup and VDD diet in the biogenesis of MetS and NAFLD. C57BL/6J mice were treated with four conditions for 28 weeks: control (standard chow and sterile water), fructose drinking (FD, standard chow and 20 g/100 mL fructose in drinking water), VDD (standard chow with VD depleted and sterile water), and FD+VDD. Metabolites in the serum and liver of mice were analyzed by gas chromatography-mass spectrometry combined with trimethylsilyl derivatization. The histological results indicated that one-hit from long-term fructose drinking led to mild MetS, and a combination with VDD diet induced hepatic steatosis, inflammatory lesion, and interstitial fibrosis in mice, showing significant nonalcoholic steatohepatitis features. Metabolomics analysis showed significant changes in amino acids and short-chain organic acids in response to fructose drinking. VDD diet led to significant increase of hepatic fatty acids, which was consistent with the hepatic morphology of fat deposition. This work demonstrated a concert effect of FD and VDD in promoting MetS and NAFLD through changing in vivo metabolism and signaling pathways. And metabolomics analysis could provide early warnings for the biogenesis of MetS and NAFLD. Importantly, vitamin D supplementation in the diet can balance the metabolic disorders caused by excessive fructose intake.


Assuntos
Frutose/administração & dosagem , Síndrome Metabólica/metabolismo , Metaboloma , Hepatopatia Gordurosa não Alcoólica/metabolismo , Deficiência de Vitamina D/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL
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