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1.
Nutrients ; 14(2)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35057530

RESUMO

Fibrosis is a pathological process associated with most chronic inflammatory diseases. It is defined by an excessive deposition of extracellular matrix proteins and can affect nearly every tissue and organ system in the body. Fibroproliferative diseases, such as intestinal fibrosis, liver cirrhosis, progressive kidney disease and cardiovascular disease, often lead to severe organ damage and are a leading cause of morbidity and mortality worldwide, for which there are currently no effective therapies available. In the past decade, a growing body of evidence has highlighted the gut microbiome as a major player in the regulation of the innate and adaptive immune system, with severe implications in the pathogenesis of multiple immune-mediated disorders. Gut microbiota dysbiosis has been associated with the development and progression of fibrotic processes in various organs and is predicted to be a potential therapeutic target for fibrosis management. In this review we summarize the state of the art concerning the crosstalk between intestinal microbiota and organ fibrosis, address the relevance of diet in different fibrotic diseases and discuss gut microbiome-targeted therapeutic approaches that are current being explored.


Assuntos
Disbiose/microbiologia , Disbiose/patologia , Fibrose/microbiologia , Microbioma Gastrointestinal , Humanos
2.
Int J Mol Sci ; 22(19)2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34639117

RESUMO

Leptospirosis is a neglected infectious disease caused by pathogenic species of the genus Leptospira. The acute disease is well-described, and, although it resembles other tropical diseases, it can be diagnosed through the use of serological and molecular methods. While the chronic renal disease, carrier state, and kidney fibrosis due to Leptospira infection in humans have been the subject of discussion by researchers, the mechanisms involved in these processes are still overlooked, and relatively little is known about the establishment and maintenance of the chronic status underlying this infectious disease. In this review, we highlight recent findings regarding the cellular communication pathways involved in the renal fibrotic process, as well as the relationship between renal fibrosis due to leptospirosis and CKD/CKDu.


Assuntos
Fibrose/epidemiologia , Nefropatias/epidemiologia , Leptospira/fisiologia , Leptospirose/complicações , Animais , Fibrose/microbiologia , Humanos , Nefropatias/microbiologia , Leptospirose/microbiologia
3.
Gut Microbes ; 13(1): 1949096, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34313550

RESUMO

Crohn's disease (CD) is a major form of inflammatory bowel disease characterized by transmural inflammation along the alimentary tract. Changes in the microbial composition and reduction in species diversity are recognized as pivotal hallmarks in disease dynamics, challenging the gut barrier function and shaping a pathological immune response in genetically influenced subjects. The purpose of this review is to delve into the modification of the gut microbiota cluster network during CD progression and to discuss how this shift compromises the gut barrier integrity, granting the translocation of microbes and their products. We then complete the scope of the review by retracing gut microbiota dysbiosis interactions with the main pathophysiologic factors of CD, starting from the host's genetic background to the immune inflammatory and fibrotic processes, providing a standpoint on the lifestyle/exogenous factors and the potential benefits of targeting a specific gut microbiota.


Assuntos
Translocação Bacteriana , Doença de Crohn/complicações , Doença de Crohn/microbiologia , Doença de Crohn/fisiopatologia , Disbiose/etiologia , Disbiose/microbiologia , Microbioma Gastrointestinal/fisiologia , Fibrose/etiologia , Fibrose/microbiologia , Humanos , Inflamação/etiologia , Inflamação/microbiologia
4.
PLoS One ; 16(1): e0244763, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33395434

RESUMO

BACKGROUND & AIM: Non-alcoholic steatohepatitis (NASH) is a severe form of non-alcoholic fatty liver disease (NAFLD) that is responsible for a growing fraction of cirrhosis and liver cancer cases worldwide. Changes in the gut microbiome have been implicated in NASH pathogenesis, but the lack of suitable murine models has been a barrier to progress. We have therefore characterized the microbiome in a well-validated murine NASH model to establish its value in modeling human disease. METHODS: The composition of intestinal microbiota was monitored in mice on a 12- or 24-week NASH protocol consisting of high fat, high sugar Western Diet (WD) plus once weekly i.p injection of low-dose CCl4. Additional mice were subjected to WD-only or CCl4-only conditions to assess the independent effect of these variables on the microbiome. RESULTS: There was substantial remodeling of the intestinal microbiome in NASH mice, characterized by declines in both species diversity and bacterial abundance. Based on changes to beta diversity, microbiota from NASH mice clustered separately from controls in principal coordinate analyses. A comparison between WD-only and CCl4-only controls with the NASH model identified WD as the primary driver of early changes to the microbiome, resulting in loss of diversity within the 1st week. A NASH signature emerged progressively at weeks 6 and 12, including, most notably, a reproducible bloom of the Firmicute order Erysipelotrichales. CONCLUSIONS: We have established a valuable model to study the role of gut microbes in NASH, enabling us to identify a new NASH gut microbiome signature.


Assuntos
Disbiose/microbiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Animais , Bactérias , Dieta Ocidental/efeitos adversos , Modelos Animais de Doenças , Disbiose/complicações , Fezes/microbiologia , Fibrose/complicações , Fibrose/microbiologia , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiologia , Variação Genética/genética , Humanos , Inflamação/complicações , Cirrose Hepática/patologia , Neoplasias Hepáticas/complicações , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/microbiologia
5.
J Am Soc Nephrol ; 32(1): 69-85, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33148615

RESUMO

BACKGROUND: In children, the acute pyelonephritis that can result from urinary tract infections (UTIs), which commonly ascend from the bladder to the kidney, is a growing concern because it poses a risk of renal scarring and irreversible loss of kidney function. To date, the cellular mechanisms underlying acute pyelonephritis-driven renal scarring remain unknown. METHODS: We used a preclinical model of uropathogenic Escherichia coli-induced acute pyelonephritis to determine the contribution of neutrophils and monocytes to resolution of the condition and the subsequent development of kidney fibrosis. We used cell-specific monoclonal antibodies to eliminate neutrophils, monocytes, or both. Bacterial ascent and the cell dynamics of phagocytic cells were assessed by biophotonic imaging and flow cytometry, respectively. We used quantitative RT-PCR and histopathologic analyses to evaluate inflammation and renal scarring. RESULTS: We found that neutrophils are critical to control bacterial ascent, which is in line with previous studies suggesting a protective role for neutrophils during a UTI, whereas monocyte-derived macrophages orchestrate a strong, but ineffective, inflammatory response against uropathogenic, E. coli-induced, acute pyelonephritis. Experimental neutropenia during acute pyelonephritis resulted in a compensatory increase in the number of monocytes and heightened macrophage-dependent inflammation in the kidney. Exacerbated macrophage-mediated inflammatory responses promoted renal scarring and compromised renal function, as indicated by elevated serum creatinine, BUN, and potassium. CONCLUSIONS: These findings reveal a previously unappreciated outcome for neutrophil-macrophage imbalance in promoting host susceptibility to acute pyelonephritis and the development of permanent renal damage. This suggests targeting dysregulated macrophage responses might be a therapeutic tool to prevent renal scarring during acute pyelonephritis.


Assuntos
Cicatriz/fisiopatologia , Rim/fisiopatologia , Macrófagos/citologia , Neutrófilos/citologia , Pielonefrite/metabolismo , Animais , Escherichia coli , Feminino , Fibrose/microbiologia , Fibrose/fisiopatologia , Inflamação , Rim/microbiologia , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Neutrófilos/metabolismo , Fagocitose , Pielonefrite/microbiologia , Pielonefrite/fisiopatologia , Infecções Urinárias/microbiologia , Infecções Urinárias/fisiopatologia
6.
Aging (Albany NY) ; 12(21): 21660-21673, 2020 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-33168782

RESUMO

Effective therapies for non-alcoholic steatohepatitis (NASH) are urgently needed. We investigated the effect of human mesenchymal stem cells (hMSCs) on the intestinal flora in NASH treatment. We isolated the hMSCs from the umbilical cords and divided male C57BL/6 mice into three groups, namely, chow, methionine-choline-deficient (MCD), and MCD+hMSCs. After collecting the feces and liver of the mice, we evaluated the histological changes in the liver and measured the inflammatory and fibrogenesis cytokines. Fecal microbiome and metabolome were analyzed using 16S rRNA gene sequencing analyses. The hMSCs treatment could alleviate hepatic steatosis, inflammation and fibrosis induced by MCD diet. It could also reverse the microbiome and metabolome disorders in the NASH model. Correlation analysis of the interaction among bacteria amplified the effects of the bacteria in host. In conclusion, hMSCs treatment could improve NASH-related lesions and reverse gut microbiome and metabolome disorder in NASH.


Assuntos
Bactérias/metabolismo , Fibrose/cirurgia , Microbioma Gastrointestinal , Intestinos/microbiologia , Fígado/metabolismo , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Hepatopatia Gordurosa não Alcoólica/cirurgia , Animais , Células Cultivadas , Microambiente Celular , Modelos Animais de Doenças , Disbiose , Fezes/microbiologia , Fibrose/metabolismo , Fibrose/microbiologia , Fibrose/patologia , Interações Hospedeiro-Patógeno , Fígado/patologia , Masculino , Metaboloma , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/microbiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Fenótipo , Cordão Umbilical/citologia
7.
Khirurgiia (Mosk) ; (6): 24-30, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32573528

RESUMO

OBJECTIVE: To study and systematize clinical symptoms of tuberculous perivisceritis, to clarify diagnostic value of laboratory and instrumental survey in these patients and to identify the features of surgical treatment. MATERIAL AND METHODS: There were 8 patients with tuberculous perivisceritis. Examination included computed tomography of the abdominal cavity and chest, ultrasound, laparoscopy. All patients underwent surgical treatment with histological, cytological, microbiological and molecular genetic analysis of peritoneal exudate and biopsy of peritoneal specimens. RESULTS: Clinical picture of tuberculous perivisceritis is variable and non-specific. Periods of exacerbation are replaced by periods of prolonged remission. The complex of radiological survey used in verification of perivisceritis does not allow accurate determining the nature of disease. However, peritoneal tuberculosis may be suspected as a rule considering signs of thickening of the peritoneum. Objective confirmation of perivisceritis is possible only during surgical intervention. In this case, etiological factor can be established only after a thorough histological examination of resected fibrous capsule. CONCLUSION: Clinical picture of tuberculous perivisceritis does not have specific symptoms. The disease is characterized by prolonged and undulating course. Acute peritonitis and acute intestinal obstruction may be suspected during exacerbation of the pathological process. Laparotomy followed by complete excision of fibrous capsule and adhesiolysis is preferred.


Assuntos
Peritônio/cirurgia , Peritonite Tuberculosa/diagnóstico , Peritonite Tuberculosa/cirurgia , Aderências Teciduais/cirurgia , Doença Aguda , Fibrose/microbiologia , Fibrose/cirurgia , Humanos , Obstrução Intestinal/etiologia , Peritônio/microbiologia , Peritônio/patologia , Aderências Teciduais/microbiologia
8.
Biomarkers ; 25(4): 360-366, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32364003

RESUMO

Objective: To assess the role of ascitic endocan levels in the diagnosis of spontaneous bacterial peritonitis (SBP) in decompensated cirrhosis.Methods: Ascites samples, as well as demographic and laboratory data, were collected at admission from patients with decompensated cirrhosis. Ascitic endocan, tumour necrosis factor-α (TNF-α), and interleukin-6 (IL-6) levels were measured by ELISA. The influencing factors of SBP, the correlation of ascitic endocan with other inflammatory indicators, and the diagnostic value of ascitic endocan for SBP were analyzed.Results: A total of 167 patients were enrolled, 39 with the SBP group and 128 in the non-SBP group. Ascitic endocan, TNF-α, and IL-6 levels were significantly higher in the SBP group than in the non-SBP group (p < 0.001). Multivariate analysis demonstrated that ascitic endocan was an independent risk factor for SBP [OR = 1.006 (95% CI: 1.002-1.011); p < 0.001]. Endocan was positively correlated with ascites polymorphonuclear leukocytes, TNF-α, and IL-6. ROC curve analysis showed that ascitic endocan had an AUC of 0.805 for the diagnosis of SBP (p < 0.001) and had a sensitivity of 82.1% and specificity of 73.4% when the cut-off value was 295.011 pg/ml.Conclusions: Ascitic endocan level is an independent risk factor and a valuable diagnostic indicator for SBP in decompensated cirrhosis.


Assuntos
Biomarcadores/metabolismo , Fibrose/genética , Proteínas de Neoplasias/genética , Peritonite/genética , Proteoglicanas/genética , Adulto , Ascite/metabolismo , Ascite/patologia , Líquido Ascítico/metabolismo , Infecções Bacterianas/genética , Infecções Bacterianas/microbiologia , Infecções Bacterianas/patologia , Calcitonina/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Fibrose/complicações , Fibrose/microbiologia , Fibrose/patologia , Humanos , Interleucina-6/genética , Cirrose Hepática/complicações , Cirrose Hepática/genética , Cirrose Hepática/microbiologia , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Peritonite/complicações , Peritonite/microbiologia , Peritonite/patologia , Curva ROC , Fator de Necrose Tumoral alfa/genética
9.
Physiol Rep ; 8(6): e14401, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32227630

RESUMO

Renal scarring after pyelonephritis is linked to long-term health risks for hypertension and chronic kidney disease. Androgen exposure increases susceptibility to, and severity of, uropathogenic Escherichia coli (UPEC) pyelonephritis and resultant scarring in both male and female mice, while anti-androgen therapy is protective against severe urinary tract infection (UTI) in these models. This work employed androgenized female C57BL/6 mice to elucidate the molecular mechanisms of post-infectious renal fibrosis and to determine how these pathways are altered by the presence of androgens. We found that elevated circulating testosterone levels primed the kidney for fibrosis by increasing local production of TGFß1 before the initiation of UTI, altering the ratio of transcription factors Smad2 and Smad3 and increasing the presence of mesenchymal stem cell (MSC)-like cells and Gli1 + activated myofibroblasts, the cells primarily responsible for deposition of scar components. Increased production of TGFß1 and aberrations in Smad2:Smad3 were maintained throughout the course of infection in the presence of androgen, correlating with renal scarring that was not observed in non-androgenized female mice. Pharmacologic inhibition of TGFß1 signaling blunted myofibroblast activation. We conclude that renal fibrosis after pyelonephritis is exacerbated by the presence of androgens and involves activation of the TGFß1 signaling cascade, leading to increases in cortical populations of MSC-like cells and the Gli1 + activated myofibroblasts that are responsible for scarring.


Assuntos
Androgênios/metabolismo , Pielonefrite/metabolismo , Pielonefrite/patologia , Fator de Crescimento Transformador beta/metabolismo , Infecções Urinárias/metabolismo , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/metabolismo , Animais , Feminino , Fibrose/metabolismo , Fibrose/microbiologia , Rim/metabolismo , Rim/microbiologia , Rim/patologia , Camundongos Endogâmicos C57BL , Pielonefrite/microbiologia , Transdução de Sinais , Testosterona/administração & dosagem , Testosterona/análogos & derivados
10.
Helicobacter ; 25(2): e12677, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31881556

RESUMO

BACKGROUND: It has been documented that Helicobacter hepaticus (H hepaticus) infection is linked to chronic hepatitis and liver cancer. However, our understanding of the molecular mechanisms underlying progression of the H hepaticus-induced hepatic inflammation to cellular hepatocarcinoma is still limited. MATERIALS AND METHODS: In our study, male BALB/c mice were infected by H hepaticus for 8, 12, 16, 20, and 24 weeks. Histopathology, H hepaticus colonization dynamics, select signaling pathways, and expression of key inflammatory cytokines in the liver were examined. RESULTS: We found that H hepaticus was detectible in feces of mice at 7 days postinfection (DPI) by PCR, but it was not detected in the livers by PCR until 8 weeks postinfection (WPI). In addition, abundance of colonic and hepatic H hepaticus was progressively increased over the infection duration. H hepaticus-induced hepatic inflammation and fibrosis were aggravated over the infection duration, and necrosis or cirrhosis developed in the infected liver at 24 WPI H hepaticus infection increased levels of alanine aminotransferase and aspartate aminotransferase. Moreover, mRNA levels of Il-6 and Tnf-α were significantly elevated in the livers of H hepaticus-infected mice compared to uninfected control from 8 WPI to 24 WPI. Furthermore, Stat3, nuclear factor-κB (p65), and MAPK (Erk1/2 and p38) were activated by H hepaticus infection. CONCLUSIONS: These data demonstrated that male BALB/c mice can be used as a new mouse model of H hepaticus-induced liver diseases and that the H hepaticus-induced liver injury is triggered by NF-κB, Jak-Stat, and MAPK signaling pathways.


Assuntos
Fibrose/microbiologia , Helicobacter hepaticus , Hepatite Crônica/microbiologia , Sistema de Sinalização das MAP Quinases , NF-kappa B/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Citocinas/biossíntese , Fezes/microbiologia , Infecções por Helicobacter/patologia , Helicobacter hepaticus/genética , Helicobacter hepaticus/isolamento & purificação , Fígado/microbiologia , Fígado/patologia , Neoplasias Hepáticas/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Animais , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
11.
Am J Drug Alcohol Abuse ; 46(1): 4-12, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31689142

RESUMO

Background: A growing body of evidence highlights the role of the intestine in the development of various alcohol use disorder (AUD) complications. The intestinal microbiome has been proposed as an essential factor in mediating the development of AUD complications such as alcoholic liver disease.Objectives: To provide a comprehensive description of alcohol-induced intestinal microbiome alterations.Methods: We conducted a systematic review of studies investigating the effect of alcohol on the intestinal microbiome using the PRISMA checklist. We searched the Medline database on the PubMed platform for studies determining the effect of alcohol on microbiota in individuals with AUD. The manual search included references of retrieved articles. Only human studies examining the intestinal bacterial microbiome using 16S ribosomal RNA sequencing were included. Data comparing relative abundances of bacteria comprising intestinal microbiota was extracted.Results: We retrieved 17 studies investigating intestinal microbiome alterations in individuals with AUD. Intestinal microbiome alterations in individuals with AUD included depletion of Akkermansia muciniphila and Faecalibacterium prausnitzii and an increase of Enterobacteriaceae. At the phylum level, a higher abundance of Proteobacteria and lower of Bacteroidetes were found. Mixed results regarding Bifidobacterium were obtained. Several species of short-chain fatty acids producing bacteria had a lower abundance in individuals with alcohol use disorder.Conclusion: Intestinal microbiome alterations associated with dysbiosis in individuals with AUD are generally consistent across studies, making it a promising target in potential AUD complications treatment.


Assuntos
Alcoolismo/microbiologia , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Disbiose/microbiologia , Microbioma Gastrointestinal , Akkermansia/efeitos dos fármacos , Bactérias/classificação , Bacteroidetes/efeitos dos fármacos , Enterobacteriaceae/efeitos dos fármacos , Faecalibacterium/efeitos dos fármacos , Fibrose/microbiologia , Hepatite Alcoólica/microbiologia , Humanos , Proteobactérias/efeitos dos fármacos
12.
Am J Physiol Gastrointest Liver Physiol ; 317(5): G661-G669, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31460790

RESUMO

Posttraumatic stress disorder (PTSD) is associated with cirrhosis in veterans, and therapeutic results are suboptimal. An altered gut-liver-brain axis exists in cirrhosis due to hepatic encephalopathy (HE), but the added impact of PTSD is unclear. The aim of this study was to define linkages between gut microbiota and cognition in cirrhosis with/without PTSD. Cirrhotic veterans (with/without prior HE) underwent cognitive testing [PHES, inhibitory control test (ICT), and block design test (BDT)], serum lipopolysaccharide-binding protein (LBP) and stool collection for 16S rRNA microbiota composition, and predicted function analysis (PiCRUST). PTSD was diagnosed using DSM-V criteria. Correlation networks between microbiota and cognition were created. Patients with/without PTSD and with/without HE were compared. Ninety-three combat-exposed male veterans [ (58 yr, MELD 11, 34% HE, 31% combat-PTSD (42 no-HE/PTSD, 19 PTSD-only, 22 HE-only, 10 PTSD+HE)] were included. PTSD patients had similar demographics, alcohol history, MELD, but worse ICT/BDT, and higher antidepressant use and LBP levels. Microbial diversity was lower in PTSD (2.1 ± 0.5 vs. 2.5 ± 0.5, P = 0.03) but unaffected by alcohol/antidepressant use. PTSD (P = 0.02) and MELD (P < 0.001) predicted diversity on regression. PTSD patients showed higher pathobionts (Enterococcus and Escherichia/Shigella) and lower autochthonous genera belonging to Lachnospiraceaeae and Ruminococcaceae regardless of HE. Enterococcus was correlated with poor cognition, while the opposite was true for autochthonous taxa regardless of PTSD/HE. Escherichia/Shigella was only linked with poor cognition in PTSD patients. Gut-brain axis-associated microbiota functionality was altered in PTSD. In male cirrhotic veterans, combat-related PTSD is associated with cognitive impairment, lower microbial diversity, higher pathobionts, and lower autochthonous taxa composition and altered gut-brain axis functionality compared with non-PTSD combat-exposed patients. Cognition was differentially linked to gut microbiota, which could represent a new therapeutic target.NEW & NOTEWORTHY Posttraumatic stress disorder (PTSD) in veterans with cirrhosis was associated with poor cognitive performance. This was associated with lower gut microbial diversity in PTSD with higher pathobionts belonging to Enterococcus and Escherichia/Shigella and lower beneficial taxa belonging to Lachnospiraceaeae and Ruminococcaceae, with functional alterations despite accounting for prior hepatic encephalopathy, psychoactive drug use, or model for end-stage liver disease score. Given the suboptimal response to current therapies for PTSD, targeting the gut microbiota could benefit the altered gut-brain axis in these patients.


Assuntos
Cognição , Fibrose/microbiologia , Microbioma Gastrointestinal , Transtornos de Estresse Pós-Traumáticos/microbiologia , Idoso , Enterococcus/patogenicidade , Escherichia/patogenicidade , Fibrose/complicações , Fibrose/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Shigella/patogenicidade , Transtornos de Estresse Pós-Traumáticos/complicações , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Veteranos
13.
Inflamm Bowel Dis ; 25(10): 1629-1643, 2019 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-31066456

RESUMO

BACKGROUND: Intestinal fibrosis is a common and serious complication of Crohn's disease characterized by the accumulation of fibroblasts, deposition of extracellular matrix, and formation of scar tissue. Although many factors including cytokines and proteases contribute to the development of intestinal fibrosis, the initiating mechanisms and the complex interplay between these factors remain unclear. METHODS: Chronic infection of mice with Salmonella enterica serovar Typhimurium was used to induce intestinal fibrosis. A murine protease-specific CLIP-CHIP microarray analysis was employed to assess regulation of proteases and protease inhibitors. To confirm up- or downregulation during fibrosis, we performed quantitative real-time polymerase chain reaction (PCR) and immunohistochemical stainings in mouse tissue and tissue from patients with inflammatory bowel disease. In vitro infections were used to demonstrate a direct effect of bacterial infection in the regulation of proteases. RESULTS: Mice develop severe and persistent intestinal fibrosis upon chronic infection with Salmonella enterica serovar Typhimurium, mimicking the pathology of human disease. Microarray analyses revealed 56 up- and 40 downregulated proteases and protease inhibitors in fibrotic cecal tissue. Various matrix metalloproteases, serine proteases, cysteine proteases, and protease inhibitors were regulated in the fibrotic tissue, 22 of which were confirmed by quantitative real-time PCR. Proteases demonstrated site-specific staining patterns in intestinal fibrotic tissue from mice and in tissue from human inflammatory bowel disease patients. Finally, we show in vitro that Salmonella infection directly induces protease expression in macrophages and epithelial cells but not in fibroblasts. CONCLUSIONS: In summary, we show that chronic Salmonella infection regulates proteases and protease inhibitors during tissue fibrosis in vivo and in vitro, and therefore this model is well suited to investigating the role of proteases in intestinal fibrosis.


Assuntos
Fibrose/metabolismo , Enteropatias/metabolismo , Macrófagos/metabolismo , Peptídeo Hidrolases/metabolismo , Inibidores de Proteases/metabolismo , Salmonelose Animal/complicações , Salmonella enterica/patogenicidade , Animais , Citocinas/metabolismo , Fibrose/microbiologia , Fibrose/patologia , Perfilação da Expressão Gênica , Enteropatias/microbiologia , Enteropatias/patologia , Macrófagos/microbiologia , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Peptídeo Hidrolases/genética , Salmonelose Animal/metabolismo , Salmonelose Animal/microbiologia
14.
Front Immunol ; 10: 3036, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32038610

RESUMO

In human brucellosis, the liver is frequently affected. Brucella abortus triggers a profibrotic response on hepatic stellate cells (HSCs) characterized by inhibition of MMP-9 with concomitant collagen deposition and TGF-ß1 secretion through type 4 secretion system (T4SS). Taking into account that it has been reported that the inflammasome is necessary to induce a fibrotic phenotype in HSC, we hypothesized that Brucella infection might create a microenvironment that would promote inflammasome activation with concomitant profibrogenic phenotype in HSCs. B. abortus infection induces IL-1ß secretion in HSCs in a T4SS-dependent manner. The expression of caspase-1 (Casp-1), absent in melanoma 2 (AIM2), Nod-like receptor (NLR) containing a pyrin domain 3 (NLRP3), and apoptosis-associated speck-like protein containing a CARD (ASC) was increased in B. abortus-infected HSC. When infection experiments were performed in the presence of glyburide, a compound that inhibits NLRP3 inflammasome, or A151, a specific AIM2 inhibitor, the secretion of IL-1ß was significantly inhibited with respect to uninfected controls. The role of inflammasome activation in the induction of a fibrogenic phenotype in HSCs was determined by performing B. abortus infection experiments in the presence of the inhibitors Ac-YVAD-cmk and glyburide. Both inhibitors were able to reverse the effect of B. abortus infection on the fibrotic phenotype in HSCs. Finally, the role of inflammasome in fibrosis was corroborated in vivo by the reduction of fibrotic patches in liver from B. abortus-infected ASC, NLRP, AIM2, and cCasp-1/11 knock-out (KO) mice with respect to infected wild-type mice.


Assuntos
Brucella abortus/fisiologia , Brucelose/imunologia , Células Estreladas do Fígado/imunologia , Inflamassomos/imunologia , Interleucina-1beta/imunologia , Animais , Brucella abortus/genética , Brucelose/genética , Brucelose/microbiologia , Caspase 1/genética , Caspase 1/imunologia , Fibrose/genética , Fibrose/imunologia , Fibrose/microbiologia , Células Estreladas do Fígado/microbiologia , Humanos , Inflamassomos/genética , Interleucina-1beta/genética , Fígado/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia
15.
Artigo em Inglês | MEDLINE | ID: mdl-30425972

RESUMO

Previous studies have suggested that macrophages may contribute to acute Leptospira dissemination, as well as having a major role in kidney fibrosis. Our aim was to characterize the role of macrophages and galectin 3 (Gal-3) on the survival, clinical course, bacterial burden, interstitial nephritis, and chronic kidney fibrosis in Leptospira interrogans serovar Copenhageni (LIC)-induced experimental murine leptospirosis. C57BL/6J mice depleted of macrophages by liposome-encapsulated clodronate treatment and infected with LIC presented a higher bacterial burden, had reduced subacute nephritis and enhanced chronic kidney fibrosis relative to untreated, infected mice. Moreover, LIC infection in mice whose Gal-3 was disrupted (Lgals3-/-) had a higher bacterial burden and enhanced subacute nephritis and chronic kidney fibrosis when compared to C57BL/6J wild-type mice. Chronic fibrosis did not correlate with higher transcription levels of TGF-ß1 or IL-13 in the kidneys. Kidney fibrosis was found in chronically infected rats as well as in wild infected rats. On the other hand, human fibroblast cultures exhibited enhanced differentiation to myofibroblasts after treatment with LIC. Our results demonstrate that macrophages and Gal-3 play a critical role in controlling the LIC burden but has a minor role in subsequent fibrosis. Instead, kidney fibrosis was better correlated with bacterial burden. Taken together, our results do not support a role for macrophages to disseminate leptospires during acute infection, nor in chronic kidney fibrosis.


Assuntos
Carga Bacteriana , Fibrose/patologia , Galectina 3/metabolismo , Nefropatias/patologia , Leptospira interrogans/patogenicidade , Leptospirose/patologia , Macrófagos/imunologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Fibrose/microbiologia , Humanos , Nefropatias/microbiologia , Leptospira interrogans/isolamento & purificação , Leptospirose/microbiologia , Camundongos Endogâmicos C57BL , Ratos
16.
Infection ; 46(6): 793-799, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30066228

RESUMO

PURPOSE: Endotoxin is a component of the outer membrane of gram-negative bacteria that live in the intestine. Endotoxinemia is reported in non-alcoholic fatty liver disease and in cirrhotic patients, causing various biological and clinical effects in the host. It is not known whether endotoxinemia occurs in chronic hepatitis C patients (CHC), therefore we evaluated the occurrence of endotoxinemia and its effect on inflammation, liver damage, insulin resistance (IR) and atherosclerosis. METHODS: Consecutive CHC patients assessed by liver biopsy were enrolled. Endotoxinemia was evaluated by LAL test. IR was estimated by HOMA-IR. Serum TNF-α, IL-8, adiponectin and MCP-1 were measured with ELISA tests. Oxidative stress was estimated by circulating IgG against malondialdehyde adducts with human serum albumin (MDA-HAS). Carotid atherosclerosis was assessed by ultrasonography. RESULTS: Endotoxinemia was found in 60% of the 126 patients enrolled. A serum level-dependent association between endotoxinemia, steatosis (p < 0.001) and HOMA-IR (p < 0.006) was observed. Patients with endotoxinemia showed significant increase in TNF-α and IL8 levels. TNF-α correlated with steatosis (p <  0.001) and HOMA-IR (p < 0.03), whereas IL8 correlated with steatosis (p =  <0.001), TNF-α (p < 0.04) and atherosclerosis (p < 0.01). The highest levels of endotoxinemia were associated with oxidative stress and a higher prevalence of carotid atherosclerosis. Multivariate logistic regression analysis showed that the independent factors associated with endotoxinemia were hepatic steatosis, HOMA-IR, IL8 and MDA-HAS. CONCLUSIONS: Endotoxinemia occurs with high frequency in CHC patients and contributes to the development of hepatic steatosis, IR and atherosclerosis through increased pro-inflammatory cytokines and oxidative stress. Anti-endotoxin treatment could be of clinical relevance.


Assuntos
Aterosclerose/microbiologia , Endotoxemia/epidemiologia , Fibrose/microbiologia , Hepatite C Crônica/complicações , Inflamação/microbiologia , Resistência à Insulina , Estresse Oxidativo , Adolescente , Adulto , Idoso , Quimiocinas/metabolismo , Citocinas/metabolismo , Endotoxemia/complicações , Endotoxemia/microbiologia , Fígado Gorduroso/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
17.
BMC Infect Dis ; 18(1): 389, 2018 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-30097024

RESUMO

BACKGROUND: It is difficult to diagnose ascites infection early in cirrhotic patients. The present study was to create and evaluate a new bioscore combined with PCT, sNFI and dCHC in the diagnosis of ascites infection in cirrhotic patients. METHODS: Two hundred and fifty-nine consecutive patients were enrolled; of which 51 patients were culture-positive spontaneous bacterial peritonitis (culture-positive SBP) and 58 patients were culture-negative SBP. The efficacy of procalcitonin(PCT), c-reactive protein (CRP), white blood cell (WBC), mean fluorescence intensity of mature neutrophils(sNFI) and difference in hemoglobin concentration between newly formed and mature red blood cells(dCHC) for diagnosing ascites infection was examined. These parameters were used to create a scoring system. The scoring system was analyzed by logistic regression analysis to determine which parameters were statistically different between ascites infection and non-ascites infection patients. Receiver operating characteristic curve (ROC) was used to analyze the diagnostic ability of bioscore for ascites infection. RESULTS: In ROC analysis, the area under the curves (AUC) for PCT was 0.852 (95% CI 0.803-0.921, P < 0.001), dCHC 0.837 (95% CI 0.773-0.923, P < 0.001), CRP 0.669 (95% CI 0.610-0.732, P = 0.0624), sNFI 0.838 (95% CI 0.777-0.903, P < 0.001), and WBC 0.624 (95% CI 0.500-0.722, P = 0.0881). Multivariate analysis revealed PCT, dCHC and sNFI to be statistically significant. The combination of these three parameters in the bioscore had an AUC of 0.937 (95% CI 0.901-0.994, P < 0.001). A bioscore of ≥3.40 was considered to be statistically significant in making a positive diagnosis of ascites infection. In different groups of ascites infection, bioscore also shown a high diagnostic value of AUC was 0.947(95% CI 0.882-0.988, P < 0.001) and 0.929 (95% CI 0.869-0.974, P < 0.001) for culture-positive SBP and culture-negative SBP group respectively. CONCLUSION: The composite markers of combining PCT, dCHC and sNFI could be a valuable diagnostic score to early diagnose ascites infection in patients with cirrhosis.


Assuntos
Ascite/diagnóstico , Infecções Bacterianas/diagnóstico , Biomarcadores , Peritonite/diagnóstico , Adulto , Idoso , Ascite/microbiologia , Infecções Bacterianas/complicações , Infecções Bacterianas/microbiologia , Biomarcadores/análise , Biomarcadores/sangue , Biomarcadores/metabolismo , Proteína C-Reativa/análise , Proteína C-Reativa/metabolismo , Peptídeo Relacionado com Gene de Calcitonina , Contagem de Eritrócitos , Eritrócitos/patologia , Feminino , Fibrose/complicações , Fibrose/diagnóstico , Fibrose/microbiologia , Humanos , Leucócitos/metabolismo , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Cirrose Hepática/microbiologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/patologia , Peritonite/complicações , Peritonite/microbiologia , Pró-Calcitonina/análise , Pró-Calcitonina/sangue , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Mucosal Immunol ; 11(5): 1466-1476, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29988118

RESUMO

Tumor necrosis factor-like cytokine 1A (TL1A, TNFSF15) is implicated in inflammatory bowel disease (IBD), modulating the location and severity of intestinal inflammation and fibrosis. TL1A expression is increased in inflamed gut mucosa and associated with fibrostenosing Crohn's disease. Tl1a-overexpression in mice lead to spontaneous ileitis, and exacerbated induced proximal colitis and fibrosis. IBD is associated with shifts in the gut microbiome, but the effect of differing microbial populations and their interaction with TL1A on fibrosis has not been investigated. We demonstrate that the pro-fibrotic and inflammatory phenotype resulting from Tl1a-overexpression is abrogated in the absence of resident microbiota. To evaluate if this is due to the absence of a unique bacterial population, as opposed to any bacteria per se, we gavaged germ-free (GF) wild-type and Tl1a-transgenic (Tl1a-Tg) mice with stool from specific pathogen free (SPF) mice and a healthy human donor (Hu). Reconstitution with SPF, but not Hu microbiota, resulted in increased intestinal collagen deposition and fibroblast activation in Tl1a-Tg mice. Notably, there was reduced fibroblast migration and activation under GF conditions compared to native conditions. We then identified several candidate organisms that correlated directly with increased fibrosis in reconstituted mice and showed that these organisms directly impact fibroblast function in vitro. Thus, Tl1a-mediated intestinal fibrosis and fibroblast activation are dependent on specific microbial populations.


Assuntos
Fibrose/metabolismo , Fibrose/microbiologia , Microbioma Gastrointestinal/fisiologia , Inflamação/metabolismo , Intestinos/microbiologia , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Animais , Colite/metabolismo , Colite/microbiologia , Colágeno/metabolismo , Doença de Crohn/metabolismo , Doença de Crohn/microbiologia , Fibroblastos/metabolismo , Fibroblastos/microbiologia , Humanos , Ileíte/metabolismo , Ileíte/microbiologia , Inflamação/microbiologia , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/microbiologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
19.
Trends Microbiol ; 26(7): 611-623, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29289422

RESUMO

Chlamydia trachomatis, a leading bacterial cause of sexually transmitted infection-induced infertility, is frequently detected in the gastrointestinal tract. Chlamydia muridarum, a model pathogen for investigating C. trachomatis pathogenesis, readily spreads from the mouse genital tract to the gastrointestinal tract, establishing long-lasting colonization. C. muridarum mutants, despite their ability to activate acute oviduct inflammation, are attenuated in inducing tubal fibrosis and are no longer able to colonize the gastrointestinal tract, suggesting that the spread of C. muridarum to the gastrointestinal tract may contribute to its pathogenicity in the upper genital tract. However, gastrointestinal C. muridarum cannot directly autoinoculate the genital tract. Both antigen-specific CD8+ T cells and profibrotic cytokines, such as TNFα and IL-13, are essential for C. muridarum to induce tubal fibrosis; this may be induced by the gastrointestinal C. muridarum, as a second hit, to transmucosally convert tubal repairing - initiated by C. muridarum infection of tubal epithelial cells (serving as the first hit) - into pathogenic fibrosis. Testing the two-hit mouse model should both add new knowledge to the growing list of mechanisms by which gastrointestinal microbes contribute to pathologies in extragastrointestinal tissues and provide information for investigating the potential role of gastrointestinal C. trachomatis in human chlamydial pathogenesis.


Assuntos
Infecções por Chlamydia/microbiologia , Chlamydia/patogenicidade , Trato Gastrointestinal/microbiologia , Genitália/microbiologia , Animais , Antígenos de Bactérias , Linfócitos T CD8-Positivos/imunologia , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/imunologia , Chlamydia muridarum/patogenicidade , Chlamydia trachomatis/patogenicidade , Citocinas , Modelos Animais de Doenças , Fibrose/microbiologia , Humanos , Camundongos , Infecções do Sistema Genital/microbiologia , Infecções Sexualmente Transmissíveis/microbiologia , Virulência , Fatores de Virulência
20.
Infect Immun ; 86(1)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29084894

RESUMO

The reproductive system complications of genital chlamydial infection include fallopian tube fibrosis and tubal factor infertility. However, the molecular pathogenesis of these complications remains poorly understood. The induction of pathogenic epithelial-mesenchymal transition (EMT) through microRNA (miRNA) dysregulation was recently proposed as the pathogenic basis of chlamydial complications. Focusing on fibrogenesis, we investigated the hypothesis that chlamydia-induced fibrosis is caused by EMT-driven generation of myofibroblasts, the effector cells of fibrosis that produce excessive extracellular matrix (ECM) proteins. The results revealed that the targets of a major category of altered miRNAs during chlamydial infection are key components of the pathophysiological process of fibrogenesis; these target molecules include collagen types I, III, and IV, transforming growth factor ß (TGF-ß), TGF-ß receptor 1 (TGF-ßR1), connective tissue growth factor (CTGF), E-cadherin, SRY-box 7 (SOX7), and NFAT (nuclear factor of activated T cells) kinase dual-specificity tyrosine (Y) phosphorylation-regulated kinase 1a (Dyrk1a). Chlamydial induction of EMT resulted in the generation of α-smooth muscle actin (α-SMA)-positive myofibroblasts that produced ECM proteins, including collagen types I and III and fibronectin. Furthermore, the inhibition of EMT prevented the generation of myofibroblasts and production of ECM proteins during chlamydial infection. These findings may provide useful avenues for targeting EMT or specific components of the EMT pathways as a therapeutic intervention strategy to prevent chlamydia-related complications.


Assuntos
Infecções por Chlamydia/complicações , Infecções por Chlamydia/patologia , Chlamydia/patogenicidade , Transição Epitelial-Mesenquimal/fisiologia , Fibrose/etiologia , Fibrose/patologia , Actinas/metabolismo , Animais , Caderinas/metabolismo , Linhagem Celular , Infecções por Chlamydia/microbiologia , Colágeno/metabolismo , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Fibrose/microbiologia , Camundongos , MicroRNAs/metabolismo , Miofibroblastos/microbiologia , Miofibroblastos/patologia , Fatores de Transcrição NFATC/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fatores de Transcrição SOXF/metabolismo , Fator de Crescimento Transformador beta/metabolismo
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