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1.
Biosci Rep ; 44(5)2024 May 29.
Article in English | MEDLINE | ID: mdl-38660995

ABSTRACT

Several models of mice-fed high-fat diets have been used to trigger non-alcoholic steatohepatitis and some chemical substances, such as carbon tetrachloride. The present study aimed to evaluate the joint action of a high-fat diet and CCl4 in developing a short-term non-alcoholic steatohepatitis model. C57BL6/J mice were divided into two groups: standard diet-fed (SD), the high-fat diet-fed (HFD) and HFD + fructose-fed and carbon tetrachloride (HFD+CCl4). The animals fed with HFD+CCl4 presented increased lipid deposition compared with both SD and HFD mice. Plasma cholesterol was increased in animals from the HFD+CCl4 group compared with the SD and HFD groups, without significant differences between the SD and HFD groups. Plasma triglycerides showed no significant difference between the groups. The HFD+CCl4 animals had increased collagen deposition in the liver compared with both SD and HFD groups. Hydroxyproline was also increased in the HFD+CCl4 group. Liver enzymes, alanine aminotransferase and aspartate aminotransferase, were increased in the HFD+CCl4 group, compared with SD and HFD groups. Also, CCl4 was able to trigger an inflammatory process in the liver of HFD-fed animals by promoting an increase of ∼2 times in macrophage activity, ∼6 times in F4/80 gene expression, and pro-inflammatory cytokines (IL-1b and TNFa), in addition to an increase in inflammatory pathway protein phosphorylation (IKKbp). HFD e HFD+CCl4 animals increased glucose intolerance compared with SD mice, associated with reduced insulin-stimulated AKT activity in the liver. Therefore, our study has shown that short-term HFD feeding associated with fructose and CCl4 can trigger non-alcoholic steatohepatitis and cause damage to glucose metabolism.


Subject(s)
Carbon Tetrachloride , Diet, High-Fat , Disease Models, Animal , Liver , Mice, Inbred C57BL , Non-alcoholic Fatty Liver Disease , Animals , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/metabolism , Non-alcoholic Fatty Liver Disease/pathology , Diet, High-Fat/adverse effects , Liver/metabolism , Liver/pathology , Male , Mice , Triglycerides/blood , Triglycerides/metabolism , Fructose/adverse effects
2.
Endocr Relat Cancer ; 29(11): 599-613, 2022 11 01.
Article in English | MEDLINE | ID: mdl-36040817

ABSTRACT

Children diagnosed with pediatric adrenocortical tumors (pACT) have variable outcomes, and, to date, the disease lacks robust prognostic biomarkers. The prognostic potential of tumor methylation has been demonstrated in several cancers. We aimed to evaluate the pACT methylation profile and its association with disease presentation and survival. In this cross-sectional study, we accessed the DNA methylation (MethylationEPIC Array, Illumina) of 57 primary pACT from Southeastern Brazil and the respective patients' clinicopathological features. We also applied our analysis in an independent 48 pACT methylation dataset. Unsupervised learning whole-methylome analysis showed two groups with distinct methylation signatures: pACT-1 and pACT-2. Compared to pACT-2, pACT-1 tumors were enriched with higher methylation in CpG islands, mainly in gene promoter regions. The topmost hypermethylated gene in these samples was shown to be underexpressed. Patients in the pACT-1 group were older at diagnosis and were more likely to have carcinomas and nonlocalized/advanced and recurrent/metastatic disease. Univariate and bivariate regressions showed that pACT-1 methylation signature confers superior hazard ratio of disease progression and death than known prognostic features. The methylation groups had similar frequencies of germline mutations in the TP53 gene, including the regionally frequent p.R337H. Our analysis replication validated our findings and reproduced those recently described in pACT. We demonstrated the existence of different tumor methylation signatures associated with pACT presentation and clinical evolution, even in the context of germline TP53 mutations. Our data support tumor methylation profiling as a robust and independent prognostic biomarker for pACT and suggest a list of candidate genes for further validation.


Subject(s)
Adrenal Cortex Neoplasms , DNA Methylation , Adrenal Cortex Neoplasms/genetics , Adrenal Cortex Neoplasms/pathology , Biomarkers , Biomarkers, Tumor/genetics , Child , CpG Islands , Cross-Sectional Studies , Humans , Prognosis
3.
Food Chem Toxicol ; 153: 112263, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34015426

ABSTRACT

In this study, the changes in oncogenic and tumor suppressor signaling pathways in liver and their association with serum and urinary biomarkers of aflatoxin exposure were evaluated in Wistar rats fed diets containing aflatoxin B1 (AFB1) for 90 days. Rats were divided into four groups (n = 15 per group) and assigned to dietary treatments containing 0 (control), 50 (AFB50), 100 (AFB100) and 200 µg AFB1 kg-1 diet (AFB200). Multiple preneoplastic foci of hepatocytes marked with glutathione-S-transferase-placental form (GST-P) were identified in AFB100 and AFB200 groups. Hepatocellular damage induced by AFB1 resulted in overexpression of cyclin D1 and ß-catenin. The liver expression of retinoblastoma (Rb) and p27Kip1 decreased in AFB100 and AFB200 groups, confirming the favorable conditions for neoplastic progression to hepatocellular carcinoma. All samples from rats fed AFB1-contaminated diets had quantifiable AFB1-lysine in serum or urinary AFM1 and AFB1-N7-guanine, with mean levels of 20.42-50.34 ng mL-1, 5.31-37.68 and 39.15-126.37 ng mg-1 creatinine, respectively. Positive correlations were found between AFB1-lysine, AFM1 or AFB1-N7-guanine and GST-P+, ß-catenin+ and cyclin D1+ hepatocytes, while Rb + cells negatively correlated with those AFB1 exposure biomarkers. The pathways evaluated are critical molecular mechanisms of AFB1-induced hepatocarcinogenesis in rats.


Subject(s)
Aflatoxin B1/toxicity , Cyclin D1/metabolism , Cyclin-Dependent Kinase Inhibitor p27/metabolism , Retinoblastoma Protein/metabolism , beta Catenin/metabolism , Aflatoxin B1/analogs & derivatives , Aflatoxin B1/blood , Aflatoxin B1/metabolism , Aflatoxin B1/urine , Aflatoxin M1/urine , Alanine Transaminase/metabolism , Animals , Aspartate Aminotransferases/metabolism , Biomarkers/blood , Biomarkers/urine , Gene Expression/drug effects , Guanine/analogs & derivatives , Guanine/urine , Hepatocytes/drug effects , Liver/drug effects , Liver/pathology , Lysine/blood , Male , Precancerous Conditions/chemically induced , Precancerous Conditions/pathology , Rats, Wistar
4.
Cell Death Dis ; 10(1): 11, 2018 12 21.
Article in English | MEDLINE | ID: mdl-30584243

ABSTRACT

Chronic pulmonary inflammation marked predominantly by CD4+IFN-γ+ cells is the hallmark of tuberculosis pathogenesis in immunocompetent adults, who are substantially affected by this disease. Moreover, CD4+Foxp3+ cell-mediated suppression contributes to infection susceptibility. We addressed the role of CD4+Foxp3+ cells in tuberculosis pathogenesis, because this aspect has not been addressed during chronic infection. We targeted CCR4, which induces the influx of CD4+Foxp3+ cells into the lungs. CCR4-/- mice exhibited a lower frequency of CD4+Foxp3+ cells at 15, 30, and 70 days of infection than their wild-type counterparts. However, only at 70 days of infection was an exacerbated IFN-γ-mediated immune response associated with apparent tuberculosis pathogenesis and susceptibility. In addition, CCR4-/- mice exhibited a decrease in the suppressor function of CD4+Foxp3+ cells. Adoptive transfer of Foxp3+ cells into infected CCR4-/- mice restored pulmonary inflammation and bacterial load to levels observed in wild-type mice. Our findings suggest that CD4+Foxp3+ cells play a time-dependent role in tuberculosis and highlight that CCR4 plays a critical role in the balance of IFN-γ-mediated inflammation by regulating the influx and function of CD4+Foxp3+ cells. Our findings are translationally relevant, as CD4+Foxp3+ cells or CCR4 could be a target for immunotherapy, considering the heterogeneity of tuberculosis in immunocompetent adults.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Interferon-gamma/immunology , Mycobacterium tuberculosis/immunology , Receptors, CCR4/immunology , Tuberculosis, Pulmonary/immunology , Animals , CD4-Positive T-Lymphocytes/pathology , Female , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/immunology , Interferon-gamma/genetics , Mice , Mice, Knockout , Receptors, CCR4/genetics , Tuberculosis, Pulmonary/genetics , Tuberculosis, Pulmonary/pathology
5.
Toxicol Rep ; 5: 777-784, 2018.
Article in English | MEDLINE | ID: mdl-30101081

ABSTRACT

In this study, hepatic biopsies from autopsy cases in São Paulo, Brazil, showing hepatocellular carcinoma (HCC, n = 8), cirrhosis associated with viral hepatitis (VC, n = 20), cirrhosis associated with alcoholism (AC, n = 20), and normal livers (NL or controls, n = 10) were subjected to determination of aflatoxin B1 (AFB1) and its main metabolites, and of markers of hepatic carcinogenesis Only non-metabolized AFB1 was detected in 13 samples (27.1%, N = 48) of liver disorders (HCC, VC and AC), at levels between 10.0 and 418.0 pg/g (mean: 76.6 ± 107.7 pg/g). Immuno-labeling of p53, cyclin D1, p21, ß-catenin, and Prohibitin (PB) increased mainly in HCC patients, in relation to the controls. AFB1+ samples of HCC presented higher expressions of p53, cyclin D1, p21, and ß-catenin compared with AFB1-livers. In contrast, p27, p16, and Rb immuno-labeling decreased in HCC, VC, and AC samples, compared with NL, with lowest values in AFB1+ samples for all liver disorders. Compared with NL, gene expression of cyclin D1 and PB in AFB1+ samples of HCC and AC were also higher, along with higher gene expression of p21 in VC and AC AFB1+ livers. Results indicated that patients with liver disorders were exposed to dietary aflatoxins, and that residual AFB1 in liver negatively affected the p53 and protein Rb pathways in HCC. Moreover, the presence of AFB1 in cirrhotic livers warrants concern about the potential contribution of dietary aflatoxin to disease progression during VC and AC.

6.
J Immunol Res ; 2018: 2563563, 2018.
Article in English | MEDLINE | ID: mdl-29951556

ABSTRACT

Hepatitis C virus (HCV) can escape from innate and adaptive immunity, making the immune response ineffective. Human leukocyte antigen E (HLA-E) might regulate the antiviral function of immune response and contribute to the persistence of HCV and the severity of liver disease. This study aimed to evaluate the expression of HLA-E in the liver and its association with the severity of liver disease in HCV patients. We performed a retrospective analysis of liver biopsies from 125 HCV patients and from 20 control subjects without liver disease. Liver biopsies were reviewed and classified according to severity of fibrosis and inflammatory activity. The pathologist assessed the magnitude of HLA-E expression in a semiquantitative way, attributing scores from 0 to 3. Immunohistochemistry showed positive for HLA-E in hepatocyte and Kupffer cells. The rate of HLA-E positivity in hepatocytes and Kupffer cells was significantly higher in HCV patients compared to controls. The liver samples classified as severe fibrosis and necroinflammatory activity presented greater expression of HLA-E on Kupffer cells and hepatocytes, with a significant linear association. It indicates that HLA-E expression may have an immunomodulatory effect and a possible role in the severity of liver disease in chronic hepatitis C.


Subject(s)
Gene Expression , Hepatitis C, Chronic/genetics , Histocompatibility Antigens Class I/genetics , Adult , Aged , Biopsy , Female , Hepacivirus/immunology , Hepatitis C, Chronic/diagnosis , Hepatitis C, Chronic/immunology , Hepatitis C, Chronic/virology , Hepatocytes/metabolism , Hepatocytes/pathology , Histocompatibility Antigens Class I/immunology , Humans , Immunohistochemistry , Kupffer Cells/metabolism , Liver/immunology , Liver/metabolism , Liver/pathology , Liver/virology , Male , Middle Aged , Retrospective Studies , Severity of Illness Index , HLA-E Antigens
7.
Clinics (Sao Paulo) ; 72(4): 231-237, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28492723

ABSTRACT

OBJECTIVES:: The present study was designed to evaluate the bone phenotypes and mechanisms involved in bone disorders associated with hepatic osteodystrophy. Hepatocellular disease was induced by carbon tetrachloride (CCl4). In addition, the effects of disodium pamidronate on bone tissue were evaluated. METHODS:: The study included 4 groups of 15 mice: a) C = mice subjected to vehicle injections; b) C+P = mice subjected to vehicle and pamidronate injections; c) CCl4+V = mice subjected to CCl4 and vehicle injections; and d) CCl4+P = mice subjected to CCl4 and pamidronate injections. CCl4 or vehicle was administered for 8 weeks, while pamidronate or vehicle was injected at the end of the fourth week. Bone histomorphometry and biomechanical analysis were performed in tibiae, while femora were used for micro-computed tomography and gene expression. RESULTS:: CCl4 mice exhibited decreased bone volume/trabecular volume and trabecular numbers, as well as increased trabecular separation, as determined by bone histomorphometry and micro-computed tomography, but these changes were not detected in the group treated with pamidronate. CCl4 mice showed increased numbers of osteoclasts and resorption surface. High serum levels of receptor activator of nuclear factor-κB ligand and the increased expression of tartrate-resistant acid phosphatase in the bones of CCl4 mice supported the enhancement of bone resorption in these mice. CONCLUSION:: Taken together, these results suggest that bone resorption is the main mechanism of bone loss in chronic hepatocellular disease in mice.


Subject(s)
Bone Density Conservation Agents/pharmacology , Bone Diseases, Metabolic/drug therapy , Bone Diseases, Metabolic/etiology , Bone Remodeling/drug effects , Diphosphonates/pharmacology , Liver Diseases/complications , Animals , Bone Diseases, Metabolic/metabolism , Bone Resorption/metabolism , Bone and Bones/diagnostic imaging , Bone and Bones/drug effects , Bone and Bones/metabolism , Carbon Tetrachloride , Core Binding Factor Alpha 1 Subunit/genetics , Disease Models, Animal , Liver Cirrhosis/chemically induced , Liver Cirrhosis/metabolism , Liver Diseases/metabolism , Male , Mice, Inbred C57BL , Osteoprotegerin/genetics , Pamidronate , Phosphorus/administration & dosage , RANK Ligand/genetics , Tartrate-Resistant Acid Phosphatase/genetics , X-Ray Microtomography
8.
Clin Infect Dis ; 65(4): 687-690, 2017 08 15.
Article in English | MEDLINE | ID: mdl-28444144

ABSTRACT

We report 2 fatal cases of congenital Zika virus (ZIKV) infection. Brain anomalies, including atrophy of the cerebral cortex and brainstem, and cerebellar aplasia were observed. The spinal cord showed architectural distortion, severe neuronal loss, and microcalcifications. The ZIKV proteins and flavivirus-like particles were detected in cytoplasm of spinal neurons, and spinal cord samples were positive for ZIKV RNA.


Subject(s)
Pregnancy Complications, Infectious , Spinal Cord Diseases , Spinal Cord/abnormalities , Zika Virus Infection , Zika Virus , Fatal Outcome , Female , Humans , Infant, Newborn , Male , Pregnancy , Pregnancy Complications, Infectious/pathology , Pregnancy Complications, Infectious/virology , Spinal Cord Diseases/congenital , Spinal Cord Diseases/pathology , Spinal Cord Diseases/virology , Zika Virus Infection/congenital , Zika Virus Infection/pathology , Zika Virus Infection/virology
9.
In Vivo ; 30(6): 845-852, 2016.
Article in English | MEDLINE | ID: mdl-27815471

ABSTRACT

ArtinM is a d-mannose-binding lectin found in the seeds of Artocarpus heterophyllus (jackfruit) that interacts with N-glycans, that is associated with receptors on the surface of phagocytic cells and induces the production of inflammatory mediators. Some of them are especially important because they may be required for antitumor immune response. This study aimed to evaluate the effect of ArtinM on hepatocellular preneoplastic foci. Wistar rats received 50 mg/kg of diethyl-nitrosamine (DEN) intraperitoneal weekly for 12 weeks. From the 14th week, the treated animals received 50 µg/kg of ArtinM subcutaneous every 2 weeks until the 18th week, whereas control animals were injected with vehicle alone. Preneoplastic-related factors were estimated using histological, western blotting and RT-PCR analysis. In comparison to the groups exposed to DEN, the ArtinM-treated rats showed diminution of preneoplastic foci, decreased expression of proliferating cell nuclear antigen (PCNA), increased number of nuclear p21 and p27 stained cells, augmented number of apoptotic cells, increased expression of p53, p42/44 MAPK and p21 proteins, reduced cyclin D1 (CCND1) protein levels and increased expression of TNFα and IFNγ genes. No difference was observed in interleukin 12 (IL12) protein levels. These findings indicate that ArtinM may provide protection against hepatocarcinogenesis as a result of the induction of cell-cycle blockage and pro-apoptotic mechanisms.


Subject(s)
Apoptosis/drug effects , Cell Proliferation/drug effects , Liver Neoplasms/prevention & control , Mannose-Binding Lectin/pharmacology , Precancerous Conditions/prevention & control , Animals , Apoptosis/genetics , Apoptosis Regulatory Proteins/metabolism , Artocarpus/chemistry , Blotting, Western , Cell Proliferation/genetics , Cyclin D1/metabolism , Gene Expression Regulation, Neoplastic/drug effects , Interferon-gamma/genetics , Interleukin-12/genetics , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Male , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Phytotherapy , Precancerous Conditions/genetics , Precancerous Conditions/metabolism , Proliferating Cell Nuclear Antigen/metabolism , Rats, Wistar , Reverse Transcriptase Polymerase Chain Reaction , Tumor Necrosis Factor-alpha/genetics
10.
Oncotarget ; 7(51): 84634-84644, 2016 Dec 20.
Article in English | MEDLINE | ID: mdl-27705928

ABSTRACT

BACKGROUND: Overexpression of the oncogene yes-associated-protein-1 (YAP1) is associated with increased cell proliferation in human cancers. YAP1 is a potential target of the Wnt/beta-catenin pathway, which plays an important role in adrenocortical tumors (ACT). The role of YAP1 in adrenocortical tumorigenesis has not been assessed. AIMS: To evaluate YAP1 expression in normal adrenals and pediatric ACT and its association with disease outcome. To investigate the interaction between YAP1 and the Wnt/beta-catenin pathway in adrenocortical cells. RESULTS: Strong YAP1 staining was present in fetal adrenals and pediatric ACT but weak in postnatal adrenals. In pediatric ACT, YAP1 mRNA overexpression was associated with death, recurrent/metastatic disease and lower overall survival. The inhibition of the Wnt/beta-catenin pathway increased YAP1 mRNA expression. siYAP1 increased CTNNB1/beta-catenin expression and nuclear staining regardless of DLV2, moreover, it decreased cell growth and impaired cell migration. MATERIALS AND METHODS: We assessed in 42 pediatric ACT samples the YAP1 protein expression by immunohistochemistry and mRNA expression by RT-qPCR and analyzed their association with outcome. As controls, we resort 32 fetal and postnatal normal adrenals for IHC and 10 normal adrenal cortices for RT-qPCR. The interaction between YAP1 and the Wnt/beta-catenin pathway was assessed in NCI-H295 adrenocortical cells by inhibiting the TCF/beta-catenin complex and by knocking down YAP1. CONCLUSION: YAP1 overexpression is a marker of poor prognosis for pediatric patients with ACT. In adrenocortical cells, there is a close crosstalk between YAP1 and Wnt/beta-catenin. These data open the possibility of future molecular therapies targeting Hippo/YAP1 signaling to treat advanced ACT.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Adrenal Cortex Neoplasms/metabolism , Adrenal Cortex/metabolism , Phosphoproteins/metabolism , Adaptor Proteins, Signal Transducing/genetics , Adolescent , Adrenal Cortex Neoplasms/genetics , Adrenal Cortex Neoplasms/mortality , Carcinogenesis , Cell Line, Tumor , Cell Proliferation , Child , Child, Preschool , Female , Gene Expression Regulation, Neoplastic , Humans , Infant , Male , Neoplasm Metastasis , Neoplasm Recurrence, Local , Phosphoproteins/genetics , Signal Transduction , Survival Analysis , Transcription Factors , Wnt Proteins/metabolism , YAP-Signaling Proteins , beta Catenin/metabolism
11.
J Pharm Pharmacol ; 68(1): 63-75, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26725912

ABSTRACT

OBJECTIVES: Our main objective was to investigate the mechanisms underlying the effects of hyperhomocysteinaemia (HHcy) on contractile response mediated by α1-adrenoceptors in the rat corpus cavernosum. METHODS: Concentration-response curves for phenylephrine (PE) were obtained in strips of corpus cavernosum, in absence or after incubation with tiron, tempol or polyethylene glycol (PEG)-catalase combined or not with tempol. We also measured the superoxide anion (O2(-)) and hydrogen peroxide (H2O2) generation, superoxide dismutase (SOD) and catalase activity and α-actin expression in rat corpus cavernosum from both groups. KEY FINDINGS: HHcy increased PE-induced contraction in cavernosal strips. Tiron, PEG-catalase or tempol increased PE-induced contraction in strips from control rats, but it was not altered by tiron or PEG-catalase in HHcy rats, whereas tempol reduced this response. The combination of PEG-catalase and tempol did not alter the contractile response to PE in both groups. HHcy increased O2(-) generation and SOD activity, whereas H2O2 concentration was reduced. Finally, HHcy did not alter catalase activity or expression of α-actin. CONCLUSIONS: The major new finding from this study is that HHcy induced a marked increase in PE-induced contraction in rat corpus cavernosum by a mechanism that involves increased O2(-) generation and it could play a role in the pathogenesis of erectile dysfunction associated with HHcy.


Subject(s)
Hyperhomocysteinemia/metabolism , Penis/metabolism , Reactive Oxygen Species/metabolism , Receptors, Adrenergic, alpha-1/metabolism , Actins/metabolism , Animals , Catalase/metabolism , Erectile Dysfunction/metabolism , Hydrogen Peroxide/metabolism , Male , Muscle Contraction/drug effects , Muscle Contraction/physiology , Muscle, Smooth/drug effects , Muscle, Smooth/metabolism , Penis/drug effects , Phenylephrine/pharmacology , Polyethylene Glycols/metabolism , Rats , Rats, Wistar , Superoxides/metabolism
12.
Pesqui. vet. bras ; Pesqui. vet. bras;35(5): 451-455, May 2015. tab, ilus
Article in Portuguese | LILACS | ID: lil-759375

ABSTRACT

A fumonisina B1 (FB1) é um metabólito secundário produzido principalmente por Fusarium verticilioides em diversos tipos de alimentos, principalmente o milho, o qual constitui a base para composição de rações para várias espécies de animais domésticos. A FB1é particularmente tóxica para suínos, cujas manifestações clínicas são evidentes em animais expostos a altas concentrações de FB1 na ração (em geral, acima de 30mg/kg). No entanto, são escassos os estudos sobre os efeitos da FB1em suínos alimentados com rações contendo baixas concentrações de fumonisinas, as quais são mais prováveis de serem encontradas em condições de campo. O objetivo do estudo foi avaliar os efeitos da exposição de leitões a baixos níveis de FB1 na ração, durante 28 dias, sobre o ganho de peso, consumo de ração, peso relativo de órgãos e aspectos histológicos do baço, fígado, pulmões, rins e coração. Vinte e quatro leitões foram distribuídos em 4 grupos experimentais e alimentados com rações contendo 0mg (controle), 3,0mg, 6,0mg ou 9,0mg FB1/kg de ração. As diferentes dietas não afetaram (P>0,05) o ganho de peso e nem o peso relativo dos órgãos analisados. Não foram constatadas lesões macroscópicas ou histopatológicas no baço, fígado, rins e coração. No entanto, foram observadas lesões histopatológicas nos pulmões de todos os suínos alimentados com rações contaminadas com fumonisinas, indicando que nenhum dos níveis de FB1 usados no experimento poderia ser considerado como seguro para suínos. São necessários novos estudos sobre os mecanismos de ação tóxica da FB1 em suínos, sobretudo em condições de exposição prolongada a baixos níveis de contaminação na ração.


Fumonisin B1 (FB1) is a secondary metabolite produced mainly by Fusarium verticilioides in several types of foods, particularly corn, which is the basis for composition of feed for several domestic animals. FB1 is particularly toxic to pigs, being the clinical manifestations evident in animals exposed to high concentrations of FB1 in the diet (generally above 30mg/kg). However, there are few studies on the effects of FB1 on pigs fed rations containing low concentrations of fumonisin, which are most probably found under field conditions. The aim of the study was to evaluate the effects of a 28-day exposure of piglets to low levels of FB1 in the feed on the weight gain, feed consumption, organ weights and histological aspects of the spleen, liver, lungs, kidneys and heart. Twenty-four pigs were assigned into 4 experimental groups and fed diets containing 0mg (control), 3.0mg, 6.0mg or 9.0mg FB1/kg diet. The different diets did not affect (P>0.05) the weight gain or the weight of organs examined. There were no macroscopic or histological lesions in the spleen, liver, kidneys and heart. However, histological lesions were found in the lungs from all animals fed rations containing fumonisin, hence indicating that none of the FB1 levels used in the experiment could be considered as safe for piglets. Further studies on the mechanisms of toxic action of FB1 in pigs are needed, particularly under conditions of prolonged exposure to low contamination levels in the diet.


Subject(s)
Animals , Fumonisins/analysis , Fumonisins/toxicity , Animal Feed/toxicity , Animal Feed , Weight Gain , Zea mays/toxicity , Pulmonary Edema/veterinary , Sphingolipids/biosynthesis , Sphingolipids/adverse effects , Mycotoxicosis/veterinary , Lung/physiopathology
13.
Pesqui. vet. bras ; 35(5): 451-455, maio 2015. tab, ilus
Article in Portuguese | VETINDEX | ID: vti-96370

ABSTRACT

A fumonisina B1 (FB1) é um metabólito secundário produzido principalmente por Fusarium verticilioides em diversos tipos de alimentos, principalmente o milho, o qual constitui a base para composição de rações para várias espécies de animais domésticos. A FB1é particularmente tóxica para suínos, cujas manifestações clínicas são evidentes em animais expostos a altas concentrações de FB1 na ração (em geral, acima de 30mg/kg). No entanto, são escassos os estudos sobre os efeitos da FB1em suínos alimentados com rações contendo baixas concentrações de fumonisinas, as quais são mais prováveis de serem encontradas em condições de campo. O objetivo do estudo foi avaliar os efeitos da exposição de leitões a baixos níveis de FB1 na ração, durante 28 dias, sobre o ganho de peso, consumo de ração, peso relativo de órgãos e aspectos histológicos do baço, fígado, pulmões, rins e coração. Vinte e quatro leitões foram distribuídos em 4 grupos experimentais e alimentados com rações contendo 0mg (controle), 3,0mg, 6,0mg ou 9,0mg FB1/kg de ração. As diferentes dietas não afetaram (P>0,05) o ganho de peso e nem o peso relativo dos órgãos analisados. Não foram constatadas lesões macroscópicas ou histopatológicas no baço, fígado, rins e coração. No entanto, foram observadas lesões histopatológicas nos pulmões de todos os suínos alimentados com rações contaminadas com fumonisinas, indicando que nenhum dos níveis de FB1 usados no experimento poderia ser considerado como seguro para suínos. São necessários novos estudos sobre os mecanismos de ação tóxica da FB1 em suínos, sobretudo em condições de exposição prolongada a baixos níveis de contaminação na ração.(AU)


Fumonisin B1 (FB1) is a secondary metabolite produced mainly by Fusarium verticilioides in several types of foods, particularly corn, which is the basis for composition of feed for several domestic animals. FB1 is particularly toxic to pigs, being the clinical manifestations evident in animals exposed to high concentrations of FB1 in the diet (generally above 30mg/kg). However, there are few studies on the effects of FB1 on pigs fed rations containing low concentrations of fumonisin, which are most probably found under field conditions. The aim of the study was to evaluate the effects of a 28-day exposure of piglets to low levels of FB1 in the feed on the weight gain, feed consumption, organ weights and histological aspects of the spleen, liver, lungs, kidneys and heart. Twenty-four pigs were assigned into 4 experimental groups and fed diets containing 0mg (control), 3.0mg, 6.0mg or 9.0mg FB1/kg diet. The different diets did not affect (P>0.05) the weight gain or the weight of organs examined. There were no macroscopic or histological lesions in the spleen, liver, kidneys and heart. However, histological lesions were found in the lungs from all animals fed rations containing fumonisin, hence indicating that none of the FB1 levels used in the experiment could be considered as safe for piglets. Further studies on the mechanisms of toxic action of FB1 in pigs are needed, particularly under conditions of prolonged exposure to low contamination levels in the diet.(AU)


Subject(s)
Animals , Fumonisins/analysis , Fumonisins/toxicity , Animal Feed/toxicity , Animal Feed , Zea mays/toxicity , Weight Gain , Mycotoxicosis/veterinary , Pulmonary Edema/veterinary , Sphingolipids/adverse effects , Sphingolipids/biosynthesis , Lung/physiopathology
14.
Pediatr Blood Cancer ; 61(11): 1940-8, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25156210

ABSTRACT

BACKGROUND: Low expression of HLA class II antigens has been associated with more aggressive disease in several human malignancies including adult adrenocortical tumors (ACT), but their clinical relevance in pediatric ACT needs to be investigated. PROCEDURE: This study analyzed the expression profile of three class II histocompatibility genes (HLA-DRA, HLA-DPA1, and HLA-DPB1) in 58 consecutive pediatric ACT (13 adenomas and 45 carcinomas) by quantitative real time PCR and their association with clinical and biological features. HLA-DPA1 protein level was determined by immunohistochemistry. RESULTS: A significant association (P < 0.01) was observed between lower expression levels of the three genes analyzed and poor prognostic factors such as age ≥ 4 years, tumor size ≥ 200 cm(3), tumor weight ≥ 100 g, and metastatic disease; the presence of an unfavorable event and death. Underexpression of the HLA-DRA, HLA-DPA1, and HLA-DPB1 genes were associated with lower 5-year event-free survival (EFS) (P = 0.017, P < 0.001, and P = 0.017, respectively). Cox multivariate analysis showed that HLA-DPA1 was an independent prognostic factor (P = 0.029) when analyzed in association with stage IV, age and tumor size. Significantly lower EFS was also observed in patients with negative/weak immunostaining for HLA-DPA1 (P = 0.002). Similar results were observed when only patients classified as having carcinomas were analyzed. CONCLUSION: Our results suggest that lower expression of HLA-DRA, HLA-DPA1, and HLA-DPB1 genes may contribute to more aggressive disease in pediatric ACT. HLA-DPA1 immunostaining may represent potential aggressiveness marker in this tumor.


Subject(s)
Adrenal Cortex Neoplasms/immunology , HLA-DP alpha-Chains/genetics , HLA-DP beta-Chains/genetics , HLA-DR alpha-Chains/genetics , Adolescent , Adrenal Cortex Neoplasms/mortality , Adrenal Cortex Neoplasms/pathology , Child , Child, Preschool , Female , HLA-DP alpha-Chains/analysis , HLA-DP beta-Chains/analysis , HLA-DR alpha-Chains/analysis , Humans , Infant , Male , Prognosis
15.
PLoS One ; 9(5): e95446, 2014.
Article in English | MEDLINE | ID: mdl-24787693

ABSTRACT

AIMS: C-type natriuretic peptide (CNP) and nitric oxide (NO) are endothelium-derived factors that play important roles in the regulation of vascular tone and arterial blood pressure. We hypothesized that NO produced by the endothelial NO-synthase (NOS-3) contributes to the relaxation induced by CNP in isolated rat aorta via activation of endothelial NPR-C receptor. Therefore, the aim of this study was to investigate the putative contribution of NO through NPR-C activation in the CNP induced relaxation in isolated conductance artery. MAIN METHODS: Concentration-effect curves for CNP were constructed in aortic rings isolated from rats. Confocal microscopy was used to analyze the cytosolic calcium mobilization induced by CNP. The phosphorylation of the residue Ser1177 of NOS was analyzed by Western blot and the expression and localization of NPR-C receptors was analyzed by immunohistochemistry. KEY FINDINGS: CNP was less potent in inducing relaxation in denuded endothelium aortic rings than in intact ones. L-NAME attenuated the potency of CNP and similar results were obtained in the presence of hydroxocobalamin, an intracellular NO0 scavenger. CNP did not change the phosphorylation of Ser1177, the activation site of NOS-3, when compared with control. The addition of CNP produced an increase in [Ca2+]c in endothelial cells and a decrease in [Ca2+]c in vascular smooth muscle cells. The NPR-C-receptors are expressed in endothelial and adventitial rat aortas. SIGNIFICANCE: These results suggest that CNP-induced relaxation in intact aorta isolated from rats involves NO production due to [Ca2+]c increase in endothelial cells possibly through NPR-C activation expressed in these cells. The present study provides a breakthrough in the understanding of the close relationship between the vascular actions of nitric oxide and CNP.


Subject(s)
Calcium/metabolism , Natriuretic Peptide, C-Type/pharmacology , Nitric Oxide Synthase/metabolism , Nitric Oxide/metabolism , Signal Transduction/drug effects , Vasodilation/drug effects , Vasodilation/physiology , Animals , Aorta/drug effects , Aorta/physiology , Cytosol/metabolism , Dose-Response Relationship, Drug , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Endothelium, Vascular/drug effects , Endothelium, Vascular/metabolism , Hydroxocobalamin/pharmacology , Male , Myocytes, Smooth Muscle/drug effects , Myocytes, Smooth Muscle/metabolism , NG-Nitroarginine Methyl Ester/pharmacology , Nitric Oxide Synthase Type III/metabolism , Phenylephrine/pharmacology , Phosphorylation , Rats , Receptors, Atrial Natriuretic Factor/metabolism
16.
Eur J Pharmacol ; 708(1-3): 124-38, 2013 May 15.
Article in English | MEDLINE | ID: mdl-23523715

ABSTRACT

The purpose from this study was to investigate the consequences of sensory neurocompensation to carotid balloon injury in diabetic rats on angiotensin II-induced contraction and basal blood flow in contralateral carotid. Concentration-response curves for angiotensin II and blood flow were obtained in contralateral carotid from non-treated or capsaicin-treated streptozotocin-induced diabetic rats that underwent carotid balloon injury. Diabetes increased angiotensin II-induced contraction and impaired the blood flow in non-operated rat carotid. In diabetic rats, balloon injury led to neointima formation, which reduced the blood flow in ipsilateral carotid. Carotid balloon injury in diabetic rats reduced angiotensin II-induced contraction and restored the blood flow in contralateral carotid when compared to diabetic non-operated rat carotid. Capsaicin inhibited the effects evoked by carotid balloon injury on diabetic rat contralateral carotid. Endothelium removal, PEG-catalase (hydrogen peroxide scavenger) or l-NPA (neuronal nitric oxide synthase, nNOS, inhibitor) increased angiotensin II-induced contraction in contralateral carotid from diabetic operated rats to the levels observed in diabetic non-operated rat carotid. Our findings suggest that carotid balloon injury in diabetic rats elicits a neurocompensation that attenuates the diabetic hyperreactivity to angiotensin II in contralateral carotid by a sensory nerves-dependent mechanism mediated by hydrogen peroxide derived from endothelial nNOS. This sensory mechanism also restored the blood flow in this vessel, compensating the impaired blood flow in diabetic rat ipsilateral carotid. Thus, our major conclusions are that Diabetes confers a vasoprotective significance to the neurocompensation to carotid balloon injury in preventing further damage at carotid cerebral irrigation after angioplasty in diabetic subjects.


Subject(s)
Angioplasty, Balloon/adverse effects , Carotid Artery Injuries/physiopathology , Diabetes Mellitus, Experimental/physiopathology , Diabetes Mellitus, Type 1/physiopathology , Angiotensin II , Animals , Aorta/physiopathology , Carotid Artery Injuries/metabolism , Carotid Artery Injuries/pathology , Cerebrovascular Circulation , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/pathology , Diabetes Mellitus, Type 1/metabolism , Diabetes Mellitus, Type 1/pathology , Hydrogen Peroxide/metabolism , Male , Nitric Oxide Synthase Type I/metabolism , Nitric Oxide Synthase Type III/metabolism , Rats , Rats, Wistar , Superoxides/metabolism , Vasoconstriction/physiology
18.
Am J Clin Pathol ; 136(3): 416-23, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21846917

ABSTRACT

The 2009 pandemic influenza A (H1N1) caused significant morbidity and mortality. Acute lung injury is the hallmark of the disease, but multiple organ system dysfunction can develop and lead to death. Therefore, we sought to investigate whether there was postmortem evidence of H1N1 presence and virus-induced organ injury in autopsy specimens. Five cases in which patients died of influenza A (H1N1) virus infection were studied. The lungs of all patients showed macroscopic and microscopic findings already described for H1N1 (consolidation, edema, hemorrhage, alveolar damage, hyaline membrane, and inflammation), and H1N1 viruses were present in alveolar cells in immunochemical studies. Acute tubular necrosis was present in all cases, but there was no evidence of direct virus-induced kidney injury. Nevertheless, H1N1 viruses were found in the cytoplasm of glomerular macrophages in the kidneys of 4 patients. Therefore, our data provide strong evidence that H1N1 presence is not restricted to the lungs.


Subject(s)
Influenza, Human/virology , Kidney Diseases/virology , Adult , Child , Female , Humans , Influenza A Virus, H1N1 Subtype , Influenza, Human/complications , Influenza, Human/mortality , Kidney Diseases/complications , Kidney Diseases/mortality , Male , Middle Aged , Pandemics , Retrospective Studies
19.
J Trop Pediatr ; 57(3): 222-4, 2011 Jun.
Article in English | MEDLINE | ID: mdl-20675717

ABSTRACT

We report a 2-year-old child with extrahepatic portal venous obstruction, hepatoportal sclerosis and pulmonary thromboembolism whose sole hypercoagulability factor was the presence of anti-phospholipid antibodies.


Subject(s)
Antiphospholipid Syndrome/complications , Liver/pathology , Portal Vein/pathology , Venous Thrombosis/etiology , Antiphospholipid Syndrome/diagnosis , Child, Preschool , Humans , Male , Sclerosis/etiology
20.
Pathol Res Pract ; 206(12): 800-4, 2010 Dec 15.
Article in English | MEDLINE | ID: mdl-20926203

ABSTRACT

Autoimmune hepatitis is an inflammatory chronic disease of the liver, which frequently results in cirrhosis. The present study aimed to verify the relationship between plasma cells and stellate cells in autoimmune hepatitis. Thirty-three pre-treatment, 11 post-treatment, and 10 normal liver biopsies were reviewed. Sirius Red staining (for semi-quantitative analysis of hepatic fibrosis) and immunohistochemistry were carried out: double staining for smooth muscle α-actin and plasma cell marker (for detection and localization of activated hepatic stellate cells and plasma cells, respectively); and single staining for glial fibrillary acid protein (for detection of hepatic stellate cells). We found an increase in the stellate cell population, mainly with an activated phenotype in autoimmune hepatitis, compared to the control group (liver specimens with no histological evidence of liver disease, obtained from patients undergoing hepatic resection for benign liver mass). A positive significant correlation was observed between stellate cells and scores of fibrosis (measured by Sirius Red) and the number of plasma cells. Additionally, there was a co-localization of plasma cells and activated stellate cells. We also observed a reduction in the number of plasma cells, hepatic stellate cells, and fibrosis in patients who had successfully been treated and had a second liver biopsy post-treatment. Our findings support that the number of plasma cells can be a surrogate marker for the severity of liver disease, reflecting the number of hepatic stellate cells and the amount of fibrosis. It remains to be seen if this is a result of a direct interaction between the plasma cells and hepatic stellate cells or the response to the same stimulus that affects both cellular types.


Subject(s)
Hepatic Stellate Cells/pathology , Hepatitis, Autoimmune/pathology , Liver Cirrhosis/pathology , Liver/pathology , Plasma Cells/pathology , Actins/immunology , Actins/metabolism , Adolescent , Adult , Autoantibodies/analysis , Biomarkers/metabolism , Biopsy , Child , Child, Preschool , Female , Glial Fibrillary Acidic Protein/immunology , Glial Fibrillary Acidic Protein/metabolism , Hepatic Stellate Cells/immunology , Hepatitis, Autoimmune/metabolism , Humans , Immunohistochemistry , Liver/metabolism , Liver Cirrhosis/metabolism , Male , Middle Aged , Muscle, Smooth/metabolism , Plasma Cells/immunology , Plasma Cells/metabolism , Young Adult
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