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1.
bioRxiv ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38559037

RESUMO

The thymus, a central primary lymphoid organ of the immune system, plays a key role in T cell development. Surprisingly, the thymus is quite neglected with regards to standardized pathology approaches and practices for assessing structure and function. Most studies use multispectral flow cytometry to define the dynamic composition of the thymus at the cell population level, but they are limited by lack of contextual insight. This knowledge gap hinders our understanding of various thymic conditions and pathologies, particularly how they affect thymic architecture, and subsequently, immune competence. Here, we introduce a digital pathology pipeline to address these challenges. Our approach can be coupled to analytical algorithms and utilizes rationalized morphometric assessments of thymic tissue, ranging from tissue-wide down to microanatomical and ultrastructural levels. This pipeline enables the quantitative assessment of putative changes and adaptations of thymic structure to stimuli, offering valuable insights into the pathophysiology of thymic disorders. This versatile pipeline can be applied to a wide range of conditions that may directly or indirectly affect thymic structure, ranging from various cytotoxic stimuli inducing acute thymic involution to autoimmune diseases, such as myasthenia gravis. Here, we demonstrate applicability of the method in a mouse model of age-dependent thymic involution, both by confirming established knowledge, and by providing novel insights on intrathymic remodeling in the aged thymus. Our orthogonal pipeline, with its high versatility and depth of analysis, promises to be a valuable and practical toolset for both basic and translational immunology laboratories investigating thymic function and disease.

2.
Anticancer Res ; 44(5): 1885-1894, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38677721

RESUMO

BACKGROUND/AIM: Breast cancer is a leading cause of cancer-related deaths among women. Down-regulation of the tumor suppressor gene Cyld in breast cancer has been linked to a poor prognosis. This study investigated the role of Cyld in breast cancer using conditional mutant mouse models carrying a Cyld mutation, which inactivates the deubiquitinating activity of its protein product CYLD in mammary epithelial cells. MATERIALS AND METHODS: We examined the potential of CYLD inactivation to induce mammary tumors spontaneously or modify the susceptibility of mice to mammary tumorigenesis by DMBA treatment or ErbB2 over-expression. RESULTS: CYLD inactivation significantly increased susceptibility to breast cancer induced by either DMBA treatment or ErbB2 over-expression. Moreover, while CYLD inactivation alone did not lead to spontaneous mammary tumorigenesis, it did contribute to the formation of multifocal hyperplastic lesions in virgin mice of predominantly FVB/NJ background. CONCLUSION: Our study demonstrates the tumor enhancing potential of CYLD inactivation in mammary tumorigenesis in vivo and establishes novel relevant mouse models that can be exploited for developing prognostic and therapeutic protocols.


Assuntos
Enzima Desubiquitinante CYLD , Animais , Feminino , Camundongos , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Enzima Desubiquitinante CYLD/genética , Enzima Desubiquitinante CYLD/metabolismo , Neoplasias Mamárias Experimentais/patologia , Neoplasias Mamárias Experimentais/genética , Mutação , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
3.
Int J Cancer ; 154(6): 1097-1110, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38095490

RESUMO

Gastrointestinal bacteria are known to have an impact on local and systemic immunity, and consequently either promote or suppress cancer development. Following the notion that perinatal bacterial exposure might confer immune system competency for life, we investigated whether early-life administration of cholera-toxin (CT), a protein exotoxin of the small intestine pathogenic bacterium Vibrio cholerae, may shape local and systemic immunity to impart a protective effect against tumor development in epithelia distantly located from the gut. For that, newborn mice were orally treated with low non-pathogenic doses of CT and later challenged with the carcinogen 7,12-dimethylbenzanthracene (DMBA), known to cause mainly mammary, but also skin, lung and stomach cancer. Our results revealed that CT suppressed the overall incidence and multiplicity of tumors, with varying efficiencies among cancer types, and promoted survival. Harvesting mouse tissues at an earlier time-point (105 instead of 294 days), showed that CT does not prevent preneoplastic lesions per se but it rather hinders their evolution into tumors. CT pretreatment universally increased apoptosis in the cancer-prone mammary, lung and nonglandular stomach, and altered the expression of several cancer-related molecules. Moreover, CT had a long-term effect on immune system cells and factors, the most prominent being the systemic neutrophil decrease. Finally, CT treatment significantly affected gut bacterial flora composition, leading among others to a major shift from Clostridia to Bacilli class abundance. Overall, these results support the notion that early-life CT consumption is able to affect host's immune, microbiome and gene expression profiles toward the prevention of cancer.


Assuntos
Neoplasias , Vibrio cholerae , Animais , Camundongos , Toxina da Cólera , Desmame , Carcinogênese/induzido quimicamente
4.
J Clin Med ; 12(5)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36902538

RESUMO

Neutrophil and T-cell recruitment contribute to hepatic ischemia/reperfusion injury. The initial inflammatory response is orchestrated by Kupffer cells and liver sinusoid endothelial cells. However, other cell types, including γδ-Τ cells, seem to be key mediators in further inflammatory cell recruitment and proinflammatory cytokine release, including IL17a. In this study, we used an in vivo model of partial hepatic ischemia/reperfusion injury (IRI) to investigate the role of the γδ-Τ-cell receptor (γδTcR) and the role of IL17a in the pathogenesis of liver injury. Forty C57BL6 mice were subjected to 60 min of ischemia followed by 6 h of reperfusion (RN 6339/2/2016). Pretreatment with either anti-γδΤcR antibodies or anti-IL17a antibodies resulted in a reduction in histological and biochemical markers of liver injury as well as neutrophil and T-cell infiltration, inflammatory cytokine production and the downregulation of c-Jun and NF-κΒ. Overall, neutralizing either γδTcR or IL17a seems to have a protective role in liver IRI.

5.
Animals (Basel) ; 13(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36670730

RESUMO

The impact of dietary inclusion of Spirulina platensis on the immune system, intestinal microbiome and skin of mink was investigated. Forty-eight animals were equally separated into four groups. Groups B and D were control animals, while groups A and C had their feed supplemented daily with 100 mg/kg of body weight Spirulina. Mink in groups A and B were descended from dams supplemented with spirulina during their reproductive period, while those in groups C and D were descended from dams fed the control diets. Fur growth rate and quality were graded semi-quantitatively. Fecal microbiome analysis, skin thickness histomorphometry, immunohistochemical labeling and counts of immune cells in the colon, mesenteric lymph nodes and spleen and quantitative gene expression analysis of cytokines in the colon were performed. Skin thickness, fur growth rate and skin quality were similar among groups (p > 0.05). However, differences were observed among groups concerning the relative and differential abundance of bacterial species. Tgf-ß expression was lower in group A, whereas IL-ß1 was lower in group C compared to group B (p < 0.05). Group D had significantly lower numbers of inflammatory cells in the colon and mesenteric lymph nodes. The results revealed that Spirulina decreased indices of subclinical inflammation in mink gut, while differences in the bacterial communities among groups were observed.

6.
Genes (Basel) ; 13(8)2022 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-36011319

RESUMO

Maternal microbial dysbiosis has been implicated in adverse postnatal health conditions in offspring, such as obesity, cancer, and neurological disorders. We observed that the progeny of mice fed a Westernized diet (WD) with low fiber and extra fat exhibited higher frequencies of stereotypy, hyperactivity, cranial features and lower FMRP protein expression, similar to what is typically observed in Fragile X Syndrome (FXS) in humans. We hypothesized that gut dysbiosis and inflammation during pregnancy influenced the prenatal uterine environment, leading to abnormal phenotypes in offspring. We found that oral in utero supplementation with a beneficial anti-inflammatory probiotic microbe, Lactobacillus reuteri, was sufficient to inhibit FXS-like phenotypes in offspring mice. Cytokine profiles in the pregnant WD females showed that their circulating levels of pro-inflammatory cytokine interleukin (Il)-17 were increased relative to matched gravid mice and to those given supplementary L. reuteri probiotic. To test our hypothesis of prenatal contributions to this neurodevelopmental phenotype, we performed Caesarian (C-section) births using dissimilar foster mothers to eliminate effects of maternal microbiota transferred during vaginal delivery or nursing after birth. We found that foster-reared offspring still displayed a high frequency of these FXS-like features, indicating significant in utero contributions. In contrast, matched foster-reared progeny of L. reuteri-treated mothers did not exhibit the FXS-like typical features, supporting a key role for microbiota during pregnancy. Our findings suggest that diet-induced dysbiosis in the prenatal uterine environment is strongly associated with the incidence of this neurological phenotype in progeny but can be alleviated by addressing gut dysbiosis through probiotic supplementation.


Assuntos
Síndrome do Cromossomo X Frágil , Microbioma Gastrointestinal , Limosilactobacillus reuteri , Microbiota , Animais , Citocinas , Disbiose , Feminino , Humanos , Camundongos , Gravidez
7.
Res Vet Sci ; 144: 54-65, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35074655

RESUMO

The objective of the present study was to evaluate the effects of a tributyrin and monolaurin blend compared to high ZnO levels in weaned piglets under field conditions. In Trial 1, piglets (n = 168) were assigned to 1 of 2 treatments: 1) control (CON; diet supplemented with 3000 g ZnO/t of feed; n = 8 replicates); 2) tributyrin and monolaurin blend - Porcestin™ (PR; diet supplemented with basal level of ZnO at 150 g/t and with the tested blend at 5 kg/t of feed; n = 8 replicates). In Trial 2, piglets (n = 244) were assigned to the same two treatments (n = 10 replicates). The study duration was 4 (Trial 1) and 6 (Trial 2) weeks post-weaning. In both trials, growth performance was similar between treatments (P > 0.05). In Trial 1, faecal counts of Lactobacillus spp. increased in pigs of PR group (P < 0.05). In both trials, histomorphometrical analysis of jejunum and ileum samples showed a thicker intestinal mucosa in favor of the PR treatment (P < 0.01), and Foxp3-positive regulatory T cells increased together with a concomitant decrease of MPO-positive granulocytes in jejunal mucosa of piglets from the PR treatment (P < 0.01). Overall, supplementation of monolaurin and tributyrin blend compared to high ZnO levels resulted in similar growth performance. Moreover, beneficial effects on small intestinal morphometry and immune cells responses indicate its ability to attenuate inflammatory processes. Further research is necessary to optimize the use of tested product.


Assuntos
Óxido de Zinco , Animais , Suplementos Nutricionais , Imuno-Histoquímica , Lauratos , Monoglicerídeos , Suínos , Triglicerídeos , Desmame
8.
Vet Sci ; 8(11)2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34822631

RESUMO

Canine lymphoma is a commonly reported neoplasia and, in most dogs, arises from lymph nodes before spreading to other organs. Renal lymphoma rarely occurs, and kidneys usually are a secondary site of origin. Primary renal lymphoma is infrequently described in the veterinary literature. In this study, we present a rare case of primary renal lymphoma in a dog and a review of similar cases. A 3-year-old male dog was admitted due to anorexia, weakness and vomiting. Clinical examination revealed bilaterally enlarged kidneys. Imaging demonstrated the presence of multiple renal masses. Cytology of abdominal fluid and kidneys led to the diagnosis of large cell lymphoma. Histopathology and immunohistochemistry on tissue samples taken from the kidneys confirmed the cytological diagnosis of lymphoma and categorized it as primary bilateral renal large B-cell lymphoma (LBCL).

9.
PLoS Pathog ; 17(9): e1009883, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34492088

RESUMO

SARS-CoV-2 infection outbreaks in minks have serious implications associated with animal health and welfare, and public health. In two naturally infected mink farms (A and B) located in Greece, we investigated the outbreaks and assessed parameters associated with virus transmission, immunity, pathology, and environmental contamination. Symptoms ranged from anorexia and mild depression to respiratory signs of varying intensity. Although the farms were at different breeding stages, mortality was similarly high (8.4% and 10.0%). The viral strains belonged to lineages B.1.1.218 and B.1.1.305, possessing the mink-specific S-Y453F substitution. Lung histopathology identified necrosis of smooth muscle and connective tissue elements of vascular walls, and vasculitis as the main early key events of the acute SARS-CoV-2-induced broncho-interstitial pneumonia. Molecular investigation in two dead minks indicated a consistently higher (0.3-1.3 log10 RNA copies/g) viral load in organs of the male mink compared to the female. In farm A, the infected farmers were responsible for the significant initial infection of 229 out of 1,000 handled minks, suggesting a very efficient human-to-mink transmission. Subsequent infections across the sheds wherein animals were being housed occurred due to airborne transmission. Based on a R0 of 2.90 and a growth rate equal to 0.293, the generation time was estimated to be 3.6 days, indicative of the massive SARS-CoV-2 dispersal among minks. After the end of the outbreaks, a similar percentage of animals were immune in the two farms (93.0% and 93.3%), preventing further virus transmission whereas, viral RNA was detected in samples collected from shed surfaces and air. Consequently, strict biosecurity is imperative during the occurrence of clinical signs. Environmental viral load monitoring, in conjunction with NGS should be adopted in mink farm surveillance. The minimum proportion of minks that need to be immunized to avoid outbreaks in farms was calculated at 65.5%, which is important for future vaccination campaigns.


Assuntos
COVID-19/veterinária , Vison/virologia , Animais , COVID-19/epidemiologia , COVID-19/genética , COVID-19/transmissão , Surtos de Doenças/veterinária , Microbiologia Ambiental , Fazendas , Feminino , Grécia/epidemiologia , Humanos , Masculino , Vison/genética , Exposição Ocupacional , Zoonoses Virais/transmissão , Zoonoses Virais/virologia
10.
Vet Sci ; 8(9)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34564569

RESUMO

The objective of the present study was to investigate the mechanical indices of hoof horn and their association with length measurements and lesion score. The feet of 185 culled sows from three Greek farms (A: 57 sows; B: 64 sows; C: 64 sows) were used. A slice from the dorsal wall of each claw was used to assess by a three-point bending test the Young's modulus, yield stress and aximum stress values. The available data from a companion study (part 1) on the length measurements and lesion scores of the claws were used to reveal possible relationships. The Young's modulus values were significantly higher (p < 0.001 or p < 0.01 depending on location of claw) in the sows of farm C compared to those in sows of farms A and B and in sows of farm B compared to those in the sows of farm A. Yield and maximum stress values were significantly higher (p < 0.05 or p < 0.001 depending on the location of the claw) in the sows of farm C compared to those in the sows of farm A and in the sows of farm B compared to those in the sows of farm A. An increase in heel-sole length decreased all mechanical indices. Young's modulus and yield stress were associated with wall lesion severity while maximum stress with wall and heel lesion severity. Overall, we conclude that mechanical efficiency deteriorates as length and lesion score increases.

11.
Vet Sci ; 8(7)2021 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-34357918

RESUMO

The aim of the study was to investigate variations in lengths and lesions in claws of culled sows and to evaluate their association. All four feet of 185 sows from three Greek farrow-to-finish farms (Farm A: 57 sows; Farm B: 64 sows; Farm C: 64 sows) were examined for lesions and their lengths were measured. All claw lengths were lower in sows of farm C compared to those from sows of B and A. Claw lengths in sows of farm B were lower compared to those from A for all lateral toes of front feet and for all medial and four out of three lateral toes of rear feet. Sum of length measurements of the main toes of the front feet (SLF) associated with lesions on sole, white line and heel of front feet, while sum of length measurements of the main toes of the rear feet (SLR) associated with all lesions of the rear feet. The lengths of the main toes were correlated with the length of dew claws on front and rear feet. Overall, sows' claw lesion severity and claw lengths may differ between farms and frequency of lesions is higher in longer claws.

12.
Mol Biol Rep ; 48(1): 551-562, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33393006

RESUMO

Recently, our group showed that Romidepsin, a histone deacetylase inhibitor (HDACi), suppressed diethylnitrosamine (DEN)-induced hepatocellular carcinoma (HCC) in mice. In the present study, we investigated the effect of Romidepsin-treatment on gene expression levels of components of Bmp and Notch signaling pathways, which are both known to be aberrantly regulated in hepatocarcinogenesis. Total RNA from liver tissue samples and paraffin-embedded livers were retrieved from a recent experiment where C57BL/6 mice were treated with Romidepsin 10 months after DEN challenge and sacrificed 2 months later. RT qPCR was used for quantification of gene expression and immunohistochemistry for in situ protein detection. Regarding Bmp pathway, Romidepsin HCC-suppression was found to correlate significantly with Bmp2 and Bmp7 ligand up- and down-regulation, respectively. Intracellularly, Romidepsin-treated HCC mice exhibited a significant elevation of Bmp-inhibitor Smurf2 and Bmp-target gene Id3, as compared to the HCC untreated controls. Concerning Notch signaling, higher expression levels of ligands Jag1/Dll4, accompanied by a decreased expression of receptor Notch2, were identified in the Romidepsin-treated group. Τhe anti-oncogenic effect of Romidepsin, also correlated significantly with an increased expression of Hes1 target, as well as an up- and down-regulation of Klf4 and Sox9 transcription factors, respectively. Moreover, the cancer-related genes Snai2 and p21, known to be involved in many signaling pathways, including Bmp and Notch, were also found to be downregulated in Romidepsin-treated mice. Romidepsin HCC suppression is associated with gene expression deregulation of selective components of both Bmp and Notch signaling cascades.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Depsipeptídeos/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Animais , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 7/genética , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dietilnitrosamina/toxicidade , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Fator 4 Semelhante a Kruppel , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos C57BL , Receptor Notch2/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
13.
Environ Mol Mutagen ; 62(2): 108-123, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33314311

RESUMO

Inflammation is a major risk factor for many types of cancer, including colorectal. There are two fundamentally different mechanisms by which inflammation can contribute to carcinogenesis. First, reactive oxygen and nitrogen species (RONS) can damage DNA to cause mutations that initiate cancer. Second, inflammatory cytokines and chemokines promote proliferation, migration, and invasion. Although it is known that inflammation-associated RONS can be mutagenic, the extent to which they induce mutations in intestinal stem cells has been little explored. Furthermore, it is now widely accepted that cancer is caused by successive rounds of clonal expansion with associated de novo mutations that further promote tumor development. As such, we aimed to understand the extent to which inflammation promotes clonal expansion in normal and tumor tissue. Using an engineered mouse model that is prone to cancer and within which mutant cells fluoresce, here we have explored the impact of inflammation on de novo mutagenesis and clonal expansion in normal and tumor tissue. While inflammation is strongly associated with susceptibility to cancer and a concomitant increase in the overall proportion of mutant cells in the tissue, we did not observe an increase in mutations in normal adjacent tissue. These results are consistent with opportunities for de novo mutations and clonal expansion during tumor growth, and they suggest protective mechanisms that suppress the risk of inflammation-induced accumulation of mutant cells in normal tissue.


Assuntos
Mutação/genética , Neoplasias/genética , Animais , Carcinogênese/genética , Carcinogênese/patologia , Movimento Celular/genética , Proliferação de Células/genética , Fluorescência , Inflamação/genética , Inflamação/patologia , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/patologia , Espécies Reativas de Nitrogênio/genética , Espécies Reativas de Oxigênio/metabolismo
14.
Cancers (Basel) ; 12(8)2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32722292

RESUMO

Downregulation of the cylindromatosis (CYLD) tumor suppressor has been associated with breast cancer development and progression. Here, we report a critical role for CYLD in maintaining the phenotype of mammary epithelial cells in vitro and in vivo. CYLD downregulation or inactivation induced an epithelial to mesenchymal transition of mammary epithelial cells that was dependent on the concomitant activation of the transcription factors Yes-associated protein (YAP)/transcriptional coactivator with PDZ-binding motif (TAZ) and transforming growth factor beta (TGF)signaling. CYLD inactivation enhanced the nuclear localization of YAP/TAZ and the phosphorylation of Small Mothers Against Decapentaplegic (SMAD)2/3 proteins in confluent cell culture conditions. Consistent with these findings were the hyperplastic alterations of CYLD-deficient mouse mammary epithelia, which were associated with enhanced nuclear expression of the YAP/TAZ transcription factors. Furthermore, in human breast cancer samples, downregulation of CYLD expression correlates with enhanced YAP/TAZ-regulated target gene expression. Our results identify CYLD as a critical regulator of a signaling node that prevents the coordinated activation of YAP/TAZ and the TGF pathway in mammary epithelial cells, in order to maintain their phenotypic identity and homeostasis. Consequently, they provide a novel conceptual framework that supports and explains a causal implication of deficient CYLD expression in aggressive human breast cancers.

15.
Onco Targets Ther ; 13: 5575-5588, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606772

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is a frequently diagnosed cancer and a leading cause of cancer-related death worldwide. Its rapid progression, combined with the limited treatment options at late stages, imposes the need for early detection and aggressive intervention. Based on the knowledge that hepatocarcinogenesis is significantly influenced by histone acetylation, we directed our search for novel HCC therapeutics among histone deacetylation inhibitors (HDACi). The aim of the present study was to investigate the effect of HDAC1/2 inhibitor Romidepsin in the well-established mouse model of diethylnitrosamine (DEN)-induced HCC. MATERIALS AND METHODS: C56BL/6 mice were treated with Romidepsin at the critical point of 10 months after DEN challenge and their livers were examined 2 months later using histopathology and morphometry. Protein levels were assessed in serum using ELISA and in liver tissues using Western blot and immunohistochemistry (in-situ detection). Gene expression was quantified using real-time PCR. RESULTS: Romidepsin suppressed cancer progression. This effect was associated with decreased proliferation and increased apoptosis of cancer cells. The cell cycle regulator CK2a, the anti-inflammatory molecule PPAR-γ, and the tumor suppressors PTEN and CYLD were upregulated in treated HCC. By contrast, the expression of PI3K, NF-κB p65 and c-Jun was reduced. In line with this result, the levels of two major apoptosis regulators, ie, BAD and the multifunctional protein c-Met, were lower in the blood serum of treated mice compared to the untreated mice with HCC. CONCLUSION: These findings suggest that Romidepsin, a drug currently used in the treatment of lymphoma, could also be considered in the management of early-stage HCC.

16.
Nat Microbiol ; 5(4): 642-650, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32042128

RESUMO

Although Clostridium difficile is widely considered an antibiotic- and hospital-associated pathogen, recent evidence indicates that this is an insufficient depiction of the risks and reservoirs. A common thread that links all major risk factors of infection is their association with gastrointestinal disturbances, but this relationship to C. difficile colonization has never been tested directly. Here, we show that disturbances caused by diarrhoeal events trigger susceptibility to C. difficile colonization. Using survey data of the human gut microbiome, we detected C. difficile colonization and blooms in people recovering from food poisoning and Vibrio cholerae infections. Carriers remained colonized for year-long time scales and experienced highly variable patterns of C. difficile abundance, where increased shedding over short periods of 1-2 d interrupted week-long periods in which C. difficile was undetectable. Given that short shedding events were often linked to gastrointestinal disturbances, our results help explain why C. difficile is frequently detected as a co-infecting pathogen in patients with diarrhoea. To directly test the impact of diarrhoea on susceptibility to colonization, we developed a mouse model of variable disturbance intensity, which allowed us to monitor colonization in the absence of disease. As mice exposed to avirulent C. difficile spores ingested increasing quantities of laxatives, more individuals experienced C. difficile blooms. Our results indicate that the likelihood of colonization is highest in the days immediately following acute disturbances, suggesting that this could be an important window during which transmission could be interrupted and the incidence of infection lowered.


Assuntos
Clostridioides difficile/efeitos dos fármacos , Clostridioides difficile/patogenicidade , Infecções por Clostridium/microbiologia , Diarreia/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Laxantes/efeitos adversos , Polietilenoglicóis/efeitos adversos , Actinobacteria/genética , Actinobacteria/crescimento & desenvolvimento , Actinobacteria/isolamento & purificação , Animais , Bacteroidetes/genética , Bacteroidetes/crescimento & desenvolvimento , Bacteroidetes/isolamento & purificação , Clostridioides difficile/crescimento & desenvolvimento , Infecções por Clostridium/complicações , Contagem de Colônia Microbiana , Diarreia/induzido quimicamente , Diarreia/complicações , Modelos Animais de Doenças , Fezes/microbiologia , Firmicutes/genética , Firmicutes/crescimento & desenvolvimento , Firmicutes/isolamento & purificação , Fusobactérias/genética , Fusobactérias/crescimento & desenvolvimento , Fusobactérias/isolamento & purificação , Humanos , Masculino , Camundongos , Proteobactérias/genética , Proteobactérias/crescimento & desenvolvimento , Proteobactérias/isolamento & purificação , RNA Ribossômico 16S/genética
17.
Mol Cell Biochem ; 464(1-2): 181-191, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31758376

RESUMO

Notch is an evolutionarily conserved signaling pathway with an important role in development and cell fate determination. Deregulation of Notch signaling has been associated with several pathological conditions, including cancer. Acting as an oncogene in some types of cancers and as a tumor suppressor in other, Notch effects seem to be highly context-dependent in solid tumors. In the present study, we aimed to investigate gene expression levels of Notch pathway constituents, including ligands, receptors, and target genes, during the early stages of inflammation-associated intestinal carcinogenesis. To achieve so, we used our recently developed mouse model, in which colon cancer arises in the absence of urokinase-type plasminogen activator (uPA) due to colitis induced by dextran sodium sulfate (DSS) treatment. Among the cell surface components, ligands Jag1/Jag2 and receptors Notch1/Notch2 were found to be significantly upregulated in the uPA-deficient protumorigenic inflammatory microenvironment. Moreover, several intracellular Notch modulators, i.e. Hes1, Hey1, and Klf4, were also shown to be deregulated with inflammation, yet irrespective of uPA status. Sox9 transcription factor, however, was significantly downregulated in the uPA-deficient/DSS-treated mice that developed colon adenomas as compared to the wild-type/DSS-treated group with no neoplasia identified. The latter finding supports a tumor suppressive role of Sox9 in intestinal carcinogenesis. Our results point towards an early activation of Notch signaling pathway at the receptor-ligand level in inflammation-associated colon neoplasmatogenesis developed in the absence of uPA. Interestingly, such activation may not be accompanied by deregulation of downstream Notch-target genes, possibly due to the effects of other inter-related signaling pathways.


Assuntos
Neoplasias do Colo/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/metabolismo , Receptor Notch1/biossíntese , Receptor Notch2/biossíntese , Transdução de Sinais , Ativador de Plasminogênio Tipo Uroquinase/deficiência , Animais , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Fator 4 Semelhante a Kruppel , Camundongos , Camundongos Endogâmicos BALB C , Receptor Notch1/genética , Receptor Notch2/genética
18.
Oncotarget ; 10(53): 5497-5509, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31565184

RESUMO

During the past forty years there has been an inexplicable increase in chronic inflammatory disorders, including obesity. One theory, the 'hygiene hypothesis', involves dysregulated immunity arising after too few beneficial early life microbe exposures. Indeed, earlier studies have shown that gut microbe-immune interactions contribute to smoldering inflammation, adiposity, and weight gain. Here we tested a safe and well-established microbe-based immune adjuvant to restore immune homeostasis and counteract inflammation-associated obesity in animal models. We found that consuming Vibrio cholerae exotoxin subunit B (ctB) was sufficient to inhibit age-associated obesogenic outcomes in wild type mice, including reduced crown-like structures (CLS) and granulomatous necrosis histopathology in fat depots. Administration of cholera toxin reduced weight gain irrespective of age during administration; however, exposure during youth imparted greater slenderizing effects when compared with animals receiving ctB for the first time during adulthood. Beneficial effects were transplantable to other obesity-prone animals using immune cells alone, demonstrating an immune-mediated mechanism. Taken together, we concluded that oral vaccination with cholera toxin B helps stimulate health-protective immune responses that counteract age-associated obesity.

19.
Oncotarget ; 9(50): 29536, 2018 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-30034637

RESUMO

[This corrects the article DOI: 10.18632/oncotarget.7730.].

20.
J Cancer ; 9(5): 914-922, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29581770

RESUMO

Background: To elucidate the expression of Aurora kinases (AURK) and the anticancer effects of pan-aurora kinase inhibitor Danusertib in hepatocarcinogenesis model in C56Bl6 mice. Methods: Thirty mice C56Bl6 were randomly divided into Group A or control, Group B animals who underwent experimental hepatocarcinogenesis with diethylnitrosamine (DEN), and Group C animals with DEN-induced hepatocarcinogenenesis that treated with pan-aurora kinase inhibitor Danusertib. Primary antibodies for immunochistochemistry (IHC) included rabbit antibodies against Ki-67, DKK1, INCENP, cleaved caspase-3, NF-κB p65, c-Jun, ß-catenin. Hepatocyte growth factor receptor (C-MET/HGFR) and Bcl-2 antagonist of cell death (BAD) serum levels were determined using a quantitative sandwich enzyme immunoassay technique. Results: Inhibition of AURK reduced the number of DEN-induced liver tumours. Apoptosis and proliferation was very low in both DEN-induced and anti- AURK groups respectively. The hepatocellular adenoma cells of DEN-treated mice uniformly had ample nuclear INCENP whereas in anti- AURK markedly decreased. Expression of ß-catenin, NF-kB and c-Jun did not differ in liver tumors of both AURK -depleted and non-depleted mice. Conclusions: Depletion of AURK reduced the number of DEN-induced hepatic tumours. However, their size did not differ significantly between the groups.

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