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1.
Pestic Biochem Physiol ; 199: 105770, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38458664

RESUMO

The extensive application of pesticides in agricultural production has raised significant concerns about its impact on human health. Different pesticides, including fungicides, insecticides, and herbicides, cause environmental pollution and health problems for non-target organisms. Infants and young children are so vulnerable to the harmful effects of pesticide exposure that early-life exposure to pesticides deserves focused attention. Recent research lays emphasis on understanding the mechanism between negative health impacts and early-life exposure to various pesticides. Studies have explored the impacts of exposure to these pesticides on model organisms (zebrafish, rats, and mice), as well as the mechanism of negative health effects, based on advanced methodologies like gut microbiota and multi-omics. These methodologies help comprehend the pathogenic mechanisms associated with early-life pesticide exposure. In addition to presenting health problems stemming from early-life exposure to pesticides and their pathogenic mechanisms, this review proposes expectations for future research. These proposals include focusing on identifying biomarkers that indicate early-life pesticide exposure, investigating transgenerational effects, and seeking effective treatments for diseases arising from such exposure. This review emphasizes how to understand the pathogenic mechanisms of early-life pesticide exposure through gut microbiota and multi-omics, as well as the adverse health effects of such exposure.


Assuntos
Microbioma Gastrointestinal , Inseticidas , Praguicidas , Criança , Humanos , Animais , Ratos , Camundongos , Praguicidas/toxicidade , Multiômica , Peixe-Zebra , Inseticidas/farmacologia
2.
Sci Total Environ ; 912: 169556, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38135070

RESUMO

The widespread use of cyproconazole (CPZ) enhances food security but may pose potential risks to non-target organisms. Therefore, we applied Multi-omics techniques to reveal the response of the intestinal barrier to CPZ exposure and explore whether the Bifidobacterium intervention experiment can repair the damage. First, we found that exposure to CPZ at environmentally relevant concentrations led to intestinal injury phenotype, significantly down-regulated intestinal protein gene expression, and up-regulated pro-inflammatory gene expression, further causing intestinal dysbacteriosis and metabolic disorders. In particular, by combining analysis of gut microbiota and metabolites, we noticed acetate, a key metabolite, which decreased sharply after exposure to high concentration of CPZ. Expectedly, after supplementing with Bifidobacterium (a core bacterium that produces acetate), we noticed that the acetate content was quickly restored. Further, we also verified that the increase in acetate content after Bifidobacterium supplementation at least partially promoted IL-22 secretion, which in turn stimulated the secretion of ß-defensins (zfbd-1, zfbd-2, zfbd-3), thereby repairing the intestinal damage. In conclusion, our work confirms the potential of Bifidobacterium to improve intestinal damage and metabolic dysbiosis caused by CPZ exposure. It provides directional recommendations for the application of probiotics to repair the toxicological risk of pesticide exposure.


Assuntos
Microbioma Gastrointestinal , Triazóis , Peixe-Zebra , Animais , Bifidobacterium/fisiologia , Microbioma Gastrointestinal/genética , Acetatos
3.
Ecotoxicol Environ Saf ; 163: 1-6, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30029080

RESUMO

Although isocarbophos is a widely used insecticide, its toxicity to aquatic organisms has not been well characterized. In this study, zebrafish were exposed to isocarbophos at concentrations of 50 µg L-1 and 200 µg L-1 to assess its bioaccumulation, metabolic disruption, and oxidative stress. Metabolomics analysis based on 1H NMR spectroscopy showed that 50 µg L-1 and 200 µg L-1 isocarbophos exposure induced increases in leucine, isoleucine, valine, and alanine compared to levels in the control. Lactate, creatine, and taurine were reduced in the 50 µg L-1 isocarbophos exposure group, and only lactate decreased in response to 200 µg L-1 isocarbophos. After zebrafish were exposed to 50 and 200 µg L-1 isocarbophos for 28 days, the activities of antioxidant enzymes (SOD, CAT, and GPx) and GSH contents decreased significantly in the liver. This result indicates that there was significant oxidative stress in the liver. Furthermore, changes in metabolite profiles significantly covaried with changes in several oxidative stress endpoints based on partial least squares regression. These results will contribute to the environmental risk assessment of isocarbophos and clarify the mechanism underlying its toxicity in zebrafish.


Assuntos
Inseticidas/toxicidade , Malation/análogos & derivados , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Aminoácidos/metabolismo , Animais , Catalase/metabolismo , Feminino , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Malation/toxicidade , Masculino , Metabolômica , Estresse Oxidativo/efeitos dos fármacos , Espectroscopia de Prótons por Ressonância Magnética , Superóxido Dismutase/metabolismo
4.
Chemosphere ; 205: 223-233, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29702342

RESUMO

Endosulfan, an organochloride pesticide, has been used for many commercial purposes. Endosulfan is composed of two isomers, α-endosulfan and ß-endosulfan. In biological and soil systems, endosulfan is metabolized into endosulfan sulfate. In this study, the different toxicological effects of α-endosulfan, ß-endosulfan, and endosulfan sulfate on the livers and kidneys of mice were comprehensively investigated. The results demonstrated that both endosulfan isomers and endosulfan sulfate disturbed the hepatic and renal antioxidant systems. Furthermore, 1H NMR metabolomics analysis revealed that endogenous metabolites involved in oxidative stress and energy metabolism were altered after exposure to these compounds. In the liver, the changes in hepatic endogenous metabolites and the induction of hepatic CYP450 mRNA isoforms were similar among mice treated with the three compounds, and the sulfate metabolite was the exclusive exogenous compound detected. Therefore, the metabolism of α- and ß-endosulfan to endosulfan sulfate is likely the main cause of toxicological effects in the livers of mice. However, in kidneys, the changes in the metabolome and in CYP450 mRNA expression induced by α-endosulfan and ß-endosulfan were stereoselective. Additionally, endosulfan sulfate, which induced a significant increase of renal Cyp3a11, showed a more robust disturbance of renal metabolites than either of the two isomers. These findings revealed that more attention should be given to the toxicological evaluation of endosulfan sulfate in the future.


Assuntos
Endossulfano/análogos & derivados , Endossulfano/toxicidade , Metabolismo Energético/efeitos dos fármacos , Inseticidas/toxicidade , Rim/metabolismo , Fígado/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Metaboloma , Metabolômica , Camundongos , Camundongos Endogâmicos ICR
5.
Pestic Biochem Physiol ; 143: 161-167, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29183587

RESUMO

In this study, 1H NMR based metabolomics analysis, LC-MS/MS based serum metabolomics and histopathology techniques were used to investigate the toxic effects of subacute exposure to two types of pyrethroid insecticides bifenthrin and lambda-cyhalothrin in mice. Metabolomic analysis of tissues extracts and serum showed that these two types of pyrethroid insecticides resulted in alterations of metabolites in the liver, kidney and serum of mice. Based on the altered metabolites, several significant pathways were identified, which are associated with gut microbial metabolism, lipid metabolism, nucleotide catabolism, tyrosine metabolism and energy metabolism. The results showed that bifenthrin and lambda-cyhalothrin have similarities in disruption of metabolic pathways in kidney, indicating that the toxicological mechanisms of these two types of insecticides have some likeness to each other. This study may provide novel insight into revealing differences of toxicological mechanisms between these two types of pyrethroid insecticides.


Assuntos
Inseticidas/toxicidade , Nitrilas/toxicidade , Piretrinas/toxicidade , Aminoácidos/sangue , Animais , Cromatografia Líquida , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Fígado/anatomia & histologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Metabolômica , Camundongos , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas em Tandem , Testes de Toxicidade Subaguda
6.
Environ Pollut ; 229: 264-271, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28601015

RESUMO

Although epoxiconazole is the worldwidely used fungicide, limited information is known about its toxic effects and bioaccumulation behavior in freshwater ecosystems. In this study, zebrafish were exposed to epoxiconazole at concentrations of 100 and 1000 µg L-1 for 21 d. 1H NMR-based metabolomics analysis showed that low- and high-dose epoxiconazole exposure resulted in two similar but not identical patterns for the change of endogenous metabolites related to energy, lipid and amino acid metabolism. The expression of genes associated with mitochondrial respiratory chain, ATP synthesis and fatty acid ß-oxidation were further measured to explore the reason for the disturbed energy metabolism, finding epoxiconazole had an inhibition effect on the genes expression of the above ways. Significant enantioselectivity was observed with (+)-epoxiconazole enrichment in the bioaccumulation process. These results will be of great importance in understanding the toxic effects induced by epoxiconazole and provide important basis for its comprehensive environmental assessment.


Assuntos
Compostos de Epóxi/metabolismo , Fungicidas Industriais/metabolismo , Triazóis/metabolismo , Peixe-Zebra/fisiologia , Animais , Metabolismo Energético , Compostos de Epóxi/toxicidade , Fungicidas Industriais/toxicidade , Expressão Gênica/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Metaboloma/efeitos dos fármacos , Metaboloma/fisiologia , Metabolômica/métodos , Triazóis/toxicidade
7.
J Agric Food Chem ; 65(18): 3609-3616, 2017 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-28453266

RESUMO

Previous studies have demonstrated the endocrine disruption of o,p'-DDT. In this study, we used a 1H NMR based metabolomics approach to investigate the estrogenic effects of o,p'-DDT (300 mg/kg) on the uterus and brain after 3 days of oral gavage administration, and ethynylestradiol (EE, 100 µg/kg) was used as a positive control. A supervised statistical analysis (PLS-DA) indicated that o,p'-DDT exerted both estrogenic receptor-(ER)-dependent and independent effects on the uterus but mainly ER-independent effects on the brain at metabolome levels, which was verified by coexposing with the antiestrogenic ICI 182,780. Four changed metabolites-glycine, choline, fumarate, and phenylalanine-were identified as ER-independent alterations in the uterus, while more metabolites, including γ-aminobutyrate, N-acetyl aspartate, and some amino acids, were disturbed based on the ER-independent mechanism in the brain. Together with biological end points, metabolomics is a promising approach to study potential estrogenic chemicals.


Assuntos
Encéfalo/efeitos dos fármacos , DDT/toxicidade , Disruptores Endócrinos/toxicidade , Metabolômica/métodos , Receptores de Estrogênio/metabolismo , Útero/efeitos dos fármacos , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Química Encefálica , Estrogênios , Feminino , Fumaratos/metabolismo , Glicina/metabolismo , Camundongos , Útero/química , Útero/crescimento & desenvolvimento , Útero/metabolismo
8.
Chemosphere ; 168: 1571-1577, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27938984

RESUMO

As a systemic triazole fungicide, limited information is known about diniconazole. In this study, toxicological effects and bioaccumulation behavior of diniconazole in zebrafish were both evaluated to perform an overall assessment of its environmental risk towards aquatic organisms. The 1H NMR-based metabolomics analysis revealed that 70 µg L-1 diniconazole exposure increased valine, leucine, isoleucine, alanine, lactate and choline, accompanied by decreased glucose, creatine and taurine, in comparison to the control. In the exposure group of 300 µg L-1 diniconazole, only down-regulated glucose and creatine were observed. The above results indicated that diniconazole disturbed energy metabolism, amino acid metabolism and lipid metabolism. Histological examination showed that the swell and vacuolization in the liver, as well as the reduction of spermatids in the diniconazole exposure groups. No enantioselectivity was observed in the bioaccumulation process of both 70 and 300 µg L-1 diniconazole exposure groups. The above results play a vital role for a comprehensive environmental assessment of diniconazole.


Assuntos
Fungicidas Industriais/metabolismo , Triazóis/metabolismo , Peixe-Zebra/metabolismo , Animais , Fungicidas Industriais/toxicidade , Fígado/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Metabolômica , Triazóis/toxicidade , Proteínas de Peixe-Zebra/química , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
9.
Nat Clin Pract Oncol ; 2(7): 370-5; quiz 376, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16075797

RESUMO

BACKGROUND: A 34-year-old male presented with a 5-month history of fatigue, anorexia, low fever, night sweats, and oliguria with edema of the eyelid, exacerbated by abdominal distension and mild diarrhea of 3 weeks duration. Physical examination showed positive signs of ascites, palpable spleen, slight abdominal tenderness and mild rebound tenderness in the lower abdomen, and edema of the lower limbs. Initial laboratory tests revealed abnormal liver biochemistry and increased protein concentration in the urine. Chest X-ray showed minimal pleural effusion in both sides of the thoracic cavity, and ultrasound detected moderate ascites, several small lymph nodes in the retroperitoneum, and mild splenomegaly with widening of the splenic vein. A lymph node biopsy established the diagnosis, and cytokine analysis in the serum revealed COX2 as the possible mediator. INVESTIGATIONS: Abdominal paracentesis, chest X-ray, abdominal ultrasound, thoracic and abdominal CT scans, gastroscopy, colonoscopy, biopsies of the liver, bone marrow and lymph nodes, immunophenotype staining for lymphocytes, cytokine analysis. DIAGNOSIS: COX2-related multicentric mixed-type Castleman's disease. MANAGEMENT: Chemotherapy and COX2 inhibitors.


Assuntos
Hiperplasia do Linfonodo Gigante/tratamento farmacológico , Hiperplasia do Linfonodo Gigante/enzimologia , Inibidores de Ciclo-Oxigenase/uso terapêutico , Prostaglandina-Endoperóxido Sintases/análise , Adulto , Hiperplasia do Linfonodo Gigante/patologia , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Humanos , Masculino , Proteínas de Membrana , Prostaglandina-Endoperóxido Sintases/fisiologia
10.
Artif Organs ; 28(5): 483-6, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15113343

RESUMO

The molecular adsorbent recirculating system (MARS) is a novel extracorporeal technique for liver support. We report the clinical results in a group of fourteen patients with drug-induced liver failure. Fourteen patients, aged 22-83 years, with acute or subacute liver failure [mean Child-Turcotte-Pugh (CTP) score 11 (range 8-15)] due to the intake of various drugs (diet pill overdose-2; Chinese traditional medicine (CTM)-4; antibiotic, paracetamol, tuberculostatic, or vasodilator abuse-8) were treated with one to seven sessions of MARS. Beneficial effects such as the improvement of encephalopathy and prothrombin activity, as well as a reduction of bilirubin and ammonia were recorded during MARS treatments. Thirteen out of fourteen patients survived the hospitalization (93%), and two of the discharged patients died during the follow-up of 6-12 months. The overall survival rate was about 79%. MARS therapy can contribute to the improved treatment of drug-induced liver failure patients.


Assuntos
Falência Hepática/terapia , Fígado Artificial , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Falência Hepática/induzido quimicamente , Falência Hepática/mortalidade , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida , Resultado do Tratamento
12.
Zhonghua Gan Zang Bing Za Zhi ; 11(11): 663-6, 2003 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-14636441

RESUMO

OBJECTIVES: To investigate the effect of selective cyclooxygenase-2 (COX-2) inhibitor on alcohol-induced liver injury in rats. METHODS: 58 male Wistar rats were randomly divided into three groups: control group treated with dextrose and corn oil, model group with ethanol and corn oil, treatment group with corn oil and ethanol plus a selective COX-2 inhibitor celecoxib. All treatments were injected into stomach through intragastric tubes. Liver samples were analyzed for histopathology with light microscope (LM) and transmission electron microscope (TEM), and the expression of COX-2 with western blotting. Levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum, levels of 6-Keto-prostaglandin F1 alpha (6-k-PGF1a) and thromboxane B2 (TXB2) in liver, and activity of glutathione s-transferase (GST) both in liver tissue and in plasma were measured. RESULTS: LM and TEM indicated hepatocytes were injured obviously in the model group and slightly in the treatment group. The levels of AST and ALT in serum, TXB2 in liver and the activity of GST in plasma increased significantly in the model group (t> or =2.294, P<0.05), but the activity of GST in liver decreased significantly (t=8.856, P<0.01) compared with those in the control group. To compare with the model group, the levels of AST and TXB2 decreased significantly (t=4.305, P<0.01; t=2.799, P<0.01), meanwhile the activity of GST increased significantly (t=10.134, P<0.01) in the treatment group. COX-2 expression in liver by western blotting increased significantly in the model group, compared with the control group (t=4.067, P<0.01) and the treatment group (t=2.251, P<0.05). Exceptionally, the level of 6-k-PGF1a decreased significantly (t=2.284, P<0.05) in the model group. CONCLUSION: COX-2 has involved in the alcohol-induced liver injury, and its inhibitor can diminish alcohol-induced liver injury in rats through decreasing TXB2 level


Assuntos
Inibidores de Ciclo-Oxigenase/uso terapêutico , Isoenzimas/antagonistas & inibidores , Hepatopatias Alcoólicas/prevenção & controle , Substâncias Protetoras/uso terapêutico , Animais , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Modelos Animais de Doenças , Etanol , Masculino , Prostaglandina-Endoperóxido Sintases , Ratos , Ratos Wistar , Tromboxano B2/metabolismo
13.
World J Gastroenterol ; 9(3): 595-8, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12632525

RESUMO

AIM: To determine the significance of endoscopic surveillance in the diagnosis of acute rejection after human living-donor small bowel transplantations. METHODS: Endoscopic surveillance was performed through the ileostomy after human living-donor small bowel transplantations. The intestinal mucosa was observed and biopsies were performed for pathological observations. RESULTS: Acute rejection was diagnosed in time by endoscopic surveillance. The endoscopic and pathological manifestations of acute rejection were described. CONCLUSION: Endoscopic surveillance and biopsy are reliable methods to diagnose the acute rejection after human living-donor small bowel transplantations.


Assuntos
Endoscopia Gastrointestinal , Rejeição de Enxerto/patologia , Intestino Delgado/patologia , Intestino Delgado/transplante , Doadores Vivos , Adolescente , Rejeição de Enxerto/tratamento farmacológico , Humanos , Imunossupressores/uso terapêutico , Masculino , Período Pós-Operatório
14.
Zhonghua Gan Zang Bing Za Zhi ; 10(3): 213-5, 2002 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-12113683

RESUMO

OBJECTIVE: To summarize the experience of a single treatment using molecular adsorbent recirculating system (MARS) in patients with acute-on-chronic liver failure. METHODS: Twenty-five eases treated by MARS-artificial liver were followed up and reviewed. RESULTS: The levels of serum total bilirubin, non-conjugated bilirubin and blood ammonia were significantly decreased from (618.51 200.68) mmol/L to (390.81 146.02) mmol/L (t=2.729, P<0.01), (490.03 163.39) mmol/L to (303.28 113.06) mmol/L (t =2.516, P<0.01), and (152.44 82.62)mmol/L to (84.80 13.30)mmol/L (t=2.174, P<0.05), respectively. Prothrombin activity was significantly increased from 70.55% 32.39% to 93.63% 14.20% (t=1.728, P<0.05) in patients during a single 6 h treatment with MARS. No difference was presented in the markers of liver zymogram, serum protein, kidney function, electrolyte, blood routine and blood gas analysis before and after the MARS. Thirteen of 17 patients have been cured or improved, 4 died, and the survival rate was 76.5%. CONCLUSIONS: MARS is a safe and an effective treatment for patients with liver failure.


Assuntos
Falência Hepática Aguda/terapia , Fígado Artificial , Adulto , Idoso , Amônia/sangue , Bilirrubina/sangue , Doença Crônica , Feminino , Seguimentos , Humanos , Testes de Função Renal , Falência Hepática Aguda/sangue , Testes de Função Hepática , Fígado Artificial/efeitos adversos , Masculino , Pessoa de Meia-Idade
16.
World J Gastroenterol ; 8(3): 441-5, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12046066

RESUMO

AIM: To investigate the expression and function of classical protein kinase C (PKC) isoenzymes in inducing MDR phenotype in gastric cancer cells. METHODS: Two cell lines were used in the study: gastric cancer cell SGC7901 and its drug-resistant cell SGC7901/VCR stepwise-selected by vincristine 0.3, 0.7 and 1.0 mg.L(-1), respectively. The expression of classical PKC (cPKC) isoenzymes in SGC7901 cells and SGC7901/VCR cells were detected using immunofluorescent cytochemistry, laser confocal scanning microscope and Western blot. The effects of anti-PKC isoenzymes antibody on adriamycin accumulation in SGC7901/VCR cells were determined using flow cytometric analysis. RESULTS: (1)SGC7901 cells exhibited positive staining of PKC-alpha. SGC7901/VCR cells exhibited stronger staining of PKC-alpha than SGC7901 cells. The higher dosage vincristine selected, the much stronger staining of PKC-alpha was observed on SGC7901/VCR cells. (2)Both SGC7901 and SGC7901/VCR cells exhibited positive staining of PKC-beta I and PKC-beta II with no significant difference. (3) Compared with SGC7901, SGC7901/VCR cells had decreased adriamycin accumulation and retention. Accumulation of adriamycin in SGC7901 was 5.21+/-2.56 mg.L(-1),in SGC7901/VCR 0.3 was 0.85+/-0.29 mg.L(-1), in SGC7901/VCR 0.7 was 0.81+/-0.32 mg.L(-1), and in SGC7901/VCR 1.0 was 0.80+/-0.33 mg.L(-1); Retention of adriamycin in SGC 7901 was 2.51+/-1.23 mg.L(-1), in SGC7901/VCR 0.3 was 0.47+/-0.14 mg.L(-1), in SGC7901/VCR 0.7 was 0.44+/-0.15 mg.L(-1), and in SGC 7901/VCR 1.0 was 0.41+/-0.11 mg.L(-1). (4) Fluorescence intensity presented adriamycin accumulation in SGC7901/VCR cells was increased from 1.14+/-0.36 to 2.71+/-0.94 when cells were co-incubated with anti-PKC-alpha but not with anti-PKC-beta I PKC-beta II and PKCgamma antibodies. CONCLUSION: PKC-alpha, but not PKC-beta I, PKC-beta II or PKCgamma, may play a role in multidrug resistance of gastric cancer cells SGC7901/VCR.


Assuntos
Proteína Quinase C/metabolismo , Neoplasias Gástricas/enzimologia , Antineoplásicos Fitogênicos/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Humanos , Isoenzimas/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Células Tumorais Cultivadas , Vincristina/farmacologia
17.
World J Gastroenterol ; 8(2): 328-32, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11925618

RESUMO

AIM: To investigate the effect of L-NAME on nitric oxide and gastrointestinal motility alterations in cirrhotic rats. METHODS: Rats with cirrhosis induced by carbon tetrachloride were randomly divided into two groups, one n =13 receiving 0.5mg.kg(-1) per day of N(G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, for 10 days, whereas the other group (n =13) and control (n =10) rats were administrated the same volume of 9g.L(-1) saline. Half gastric emptying time and 2h residual rate were measured by SPECT, using (99m)Tc-DTPA-labeled barium sulfate as test meal. Gastrointestinal transition time was recorded simultaneously. Serum concentration of nitric oxide (NO) was determined by the kinetic cadmium reduction and colorimetric methods. Immunohistochemical SABC method was used to observe the expression and distribution of three types of nitric oxide synthase (NOS) isoforms in the rat gastrointestinal tract. Western blot was used to detect expression of gastrointestinal NOS isoforms. RESULTS: Half gastric emptying time and trans-gastrointestinal time were significantly prolonged(124.0 +/- 26.4 min; 33.7 +/- 8.9 min; 72.1 +/- 15.3 min; P<0.01), (12.4 +/- 0.5h; 9.5 +/- 0.3h; 8.2 +/- 0.8h; P<0.01), 2h residual rate was raised in cirrhotic rats than in controls and cirrhotic rats treated with L-NAME (54.9 +/- 7.6%,13.7 +/- 3.2%, 34.9 +/- 10.3%, P<0.01). Serum concentration of NO was significantly increased in cirrhotic rats than in the other groups (8.20 +/- 2.48) micromol.L(-1), (5.94 +/-1.07) micromol.L(-1) and control (5.66 +/- 1.60 micromol.L(-1), P<0.01. NOS staining intensities which were mainly located in the gastrointestinal tissues were markedly lower in cirrhotic rats than in the controls and cirrhotic rats after treated with L-NAME. CONCLUSION: Gastrointestinal motility was remarkably inhibited in cirrhotic rats, which could be alleviated by L-NAME. Nitric oxide may play an important role in the inhibition of gastrointestinal motility in cirrhotic rats.


Assuntos
Motilidade Gastrointestinal/efeitos dos fármacos , Cirrose Hepática Experimental/fisiopatologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/sangue , Animais , Tetracloreto de Carbono/toxicidade , Sistema Digestório/diagnóstico por imagem , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/metabolismo , Inibidores Enzimáticos/farmacologia , Motilidade Gastrointestinal/fisiologia , Humanos , Masculino , Óxido Nítrico Sintase/metabolismo , Radiografia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Tomografia Computadorizada de Emissão de Fóton Único
18.
Zhonghua Zhong Liu Za Zhi ; 24(6): 557-60, 2002 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-12667324

RESUMO

OBJECTIVE: To analyze the distribution and significance of occludin mRNA expression in human gastric cancer, as well as its relationship with gastric cancer pathology and multidrug resistance (MDR) in vivo. METHODS: In situ hybridization (ISH) technique was used to evaluate the expression of occludin mRNA in 42 gastric carcinoma specimens obtained by surgery and 23 relatively normal gastric mucosa obtained by gastric endoscopy. All specimens had been stored in cryostatic section. RESULTS: Occludin mRNA was found positive in the cytoplasm of gastric glandulous epithelia as blue particles with intensive stain in 14 of 42 gastric carcinomas (33.3%), 23 of 42 paracancerous gastric tissues (54.8%), 14 of 23 relatively normal gastric tissues (60.9%), 9 of 16 well differentiated carcinomas (56.3%), 4 of 14 moderately differentiated carcinomas (28.6%), 1 of 10 poorly differentiated carcinomas (10.0%) and none of 2 mucosal carcinomas. There were significant differences in occludin mRNA positive rate between relatively normal gastric tissue and gastric cancer as well as between paracancerous gastric tissue and gastric cancer. The expression of occludin mRNA in moderately and poorly differentiated groups was gradually reduced when compared with well differentiated group, which suggests that there be a significant correlation between tumor differentiation and the expression of occludin mRNA. Furthermore, the positive signals of occludin mRNA distributed extensively in the cytoplasm of SGC7901/VCR cell, being vincristine resistant, derived from parental gastric cell line SGC7901. The positive signals of SGC7901/VCR were stronger than those of SGC7901 cells. CONCLUSION: Occludin mRNA, being mainly located in epithelial cells and its expression correlated with tumor differentiation, may be involved in the development of multi-drug resistance in gastric cancer.


Assuntos
Resistência a Múltiplos Medicamentos/fisiologia , Proteínas de Membrana/metabolismo , Neoplasias Gástricas/metabolismo , Junções Íntimas/metabolismo , Resistencia a Medicamentos Antineoplásicos/fisiologia , Humanos , Hibridização In Situ , Proteínas de Membrana/genética , Ocludina , RNA Mensageiro/metabolismo
19.
World J Gastroenterol ; 6(5): 664-670, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11819671

RESUMO

AIM:To observe the drug sensitizing effect and related mechanisms of fas gene transduction on human drug-resistant gastric cancer cell SGC7901/VCR (resistant to Vincristine).METHODS:The cell cycle alteration was observed by FACS. The sensitivity of gastric cancer cells to apoptosis was determined by in vitro apoptosis assay. The drug sensitization of cells to several anti-tumor drugs was observed by MTT assay. Immunochemical method was used to show expression of P-gp and Topo II in gastric cancer cells.RESULTS:Comparing to SGC7901 and pBK-SGC7901/VCR, fas-SGC7901/VCR showed decreasing G2 cells and increasing S cells, the G2 phase fraction of pBK-SGC7901/VCR was about 3.0 times that of fas -SGC7901/VCR but S phase fraction of fas -SGC7901/VCR was about 1.9 times that of pBK-SGC7901/VCR, indicating S phase arrest of fas-SGC7901/VCR. FACS also suggested apoptosis of fas-SGC7901/VCR.fas-SGC7901/VCR was more sensitive to apoptosis inducing agent VM-26 than pBK-SGC7901/VCR. MTT assay showed increased sensitization of fas-SGC7901/VCR to DDP, MMC and 5-FU, but same sensitization to VCR according to pBK-SGC7901/VCR. SGC7901, PBK-SGC7901/VCR and fas -SGC7901/VCR had positively stained Topo II equally. P-gp staining in pBK-SGC7901/VCR was stronger than in SGC7901, but there was little staining of P-gp in fas-SGC7901/VCR.CONCLUSION:fas gene transduction could reverse the MDR of human drug-resistant gastric cancer cell SGC7901/VCR to a degree, possibly because of higher sensitization to apoptosis and decreased expression of P-gp.

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