ABSTRACT Purpose: To evaluate the tissue content of neutral and acidic mucins, sulfomucins and sialomucins in colonic glands devoid of intestinal transit after enemas containing sucralfate and n-acetylcysteine alone or in combination. Methods: Sixty-four rats underwent intestinal transit bypass. A colonic segment was collected to compose the white group (without intervention). After derivation, the animals were divided into two groups according to whether enemas were performed daily for two or four weeks. Each group was subdivided into four subgroups according to the substance used: control group: saline 0.9%; sucralfate group (SCF): SCF 2 g/kg/day; n-acetylcysteine group (NAC): NAC 100 mg/kg/day; and SCF+NAC group: SCF 2 g/kg/day + NAC 100 mg/kg/day.Neutral and acidic mucins were stained by periodic acid-Schiff and alcian-blue techniques, respectively. The distinction between sulfomucins and sialomucin was made by the high alcian-blue iron diamine technique. The content of mucins in the colonic glands was measured by computerized morphometry. The inflammatory score was assessed using a validated scale. The results between the groups were compared by the Mann-Whitney’s test, while the variation according to time by the Kruskal-Wallis’ test (Dunn’s post-test). A significance level of 5% was adopted. Results: There was reduction in the inflammatory score regardless of the application of isolated or associated substances. Intervention with SCF+NAC increased the content of all mucin subtypes regardless of intervention time. Conclusions: The application of SCF+NAC reduced the inflammatory process of the colonic mucosa and increased the content of different types of mucins in the colonic glands of segments excluded from fecal transit.

ABSTRACT BACKGROUND: Plexiform neurofibromas represent a common neoplasia of type 1 neurofibromatosis in which neurofibromas arise from multiple nerves involving connective tissue and skin and rarely affect the colon and rectum. Co-occurrence of plexiform neurofibromas, neuroendocrine tumors with primary involvement of the rectum, and medullary thyroid carcinoma in patients with neurofibromatosis type 1 is a previously undescribed condition. The aim of this manuscript was to present a case of primary plexiform neurofibroma and neuroendocrine tumors of the upper rectum in a patient with neurofibromatosis type 1 whose genetic sequencing found a novel mutation in the neurofibromatosis type 1 gene and to review the literature. CASE REPORT: A 49-year-old woman with a familial history of neurofibromatosis type 1 complained of abdominal cramps for 6 months. She had previously been submitted for a total thyroidectomy due to medullary thyroid carcinoma. She was submitted to a colonoscopy, which identified a submucosa lesion located in the upper rectum. The patient was referred for a laparoscopic rectosigmoidectomy, and the histopathological study of the surgical specimen identified two different tumors. An immunohistochemical panel was done for histopathological confirmation of the etiology of both lesions. The results of the panel showed intense immunoexpression of S100 protein in the largest and superficial lesion, as well as positivity for chromogranin and synaptophysin in the minor and deep lesion confirming the diagnosis of rectal plexiform neurofibromas concomitant with neuroendocrine tumors. The proliferative activity rate using Ki-67 antibodies showed that both tumors had a low rate of mitotic activity (<1%). Genetic sequence panel identified an undescribed mutation in the neurofibromatosis type 1 gene (deletion, exons 2–30). The patient’s postoperative evolution was uneventful, and she remains well, without recurrence, 3 years after surgery. CONCLUSION: The co-occurrence of medullary thyroid carcinoma, plexiform neurofibromas, and neuroendocrine tumors of the rectum in patients with neurofibromatosis type 1 is an exceptional and undescribed possibility, whose diagnosis can be confirmed by the immunohistochemical staining and genetic panel.

RESUMO RACIONAL: Os neurofibromas plexiformes representam uma neoplasia frequente na neurofibromatose tipo 1 onde os neurofibromas surgem de múltiplos nervos envolvendo, também, o tecido conjuntivo e a pele raramente acometendo o cólon e o reto. A co-ocorrência de neurofibromas plexiformes, tumores neuroendócrinos, com envolvimento primário do reto, e carcinoma medular de tireoide em pacientes com neurofibromatose tipo 1 é uma condição ainda não descrita. O objetivo deste manuscrito é descrever um caso de neurofibromas plexiformes e tumores neuroendócrinos primários do reto superior, em paciente com neurofibromatose tipo 1, cujo sequenciamento genético identificou uma nova mutação no gene neurofibromatose tipo 1 e revisar a literatura sobre o tema. DESCRIÇÃO DO CASO: Mulher de 49 anos, com história familiar de neurofibromatose tipo 1 queixava-se de cólicas abdominais há seis meses. Tinha sido previamente submetida a tireoidectomia total por carcinoma medular de tireoide. Foi submetida a colonoscopia, que identificou lesão submucosa localizada no reto superior. A doente foi encaminhada para retossigmoidectomia laparoscópica, cujo estudo histopatológico do espécime cirúrgico identificou dois tumores distintos. Realizou-se painel imuno-histoquímico para confirmação histopatológica da etiologia de ambas as lesões. O resultado do painel mostrou intensa imunoexpressão da proteína S-100 da lesão superficial e de maior tamanho,e positividade para cromogranina e somatofisina da lesão mais profunda e de menores dimensões confirmando o diagnóstico de neurofibromas plexiformes retal e tumores neuroendócrinos. O índice de atividade proliferativa utilizando o anticorpo ant-Ki-67 mostrou que ambos os tumores apresentavam baixa índice mitótico (<1%). O painel genético identificou mutação no gene neurofibromatose tipo 1 (deleção, exons 2–30) ainda não descrita. A doente apresentou evolução pós-operatória sem intercorrências, permanecendo bem, sem recorrência, três anos após a cirurgia. CONCLUSÕES: A co-ocorrência de carcinoma medular de tireoide, neurofibromas plexiformes e tumores neuroendócrinos do reto em pacientes com neurofibromatose tipo 1 é uma possibilidade excepcional e ainda não descrita, cujo diagnóstico pode ser confirmado pela coloração imuno-histoquímica e painel genético.

RESUMO - RACIONAL: O estresse oxidativo é um dos principais mecanismos associados à ruptura dos mecanismos de defesa que formam a barreira epitelial cólica e reduz o conteúdo tecidual das proteínas claudina-3 e ocludina principais constituintes das junções de oclusão intercelulares. O sucralfato, possui atividade antioxidante e tem sido usado para tratar diferentes formas de colite. OBJETIVO: Mensurar o conteúdo tecidual de claudina-3 e ocludina da mucosa do cólon sem trânsito fecal, submetido à intervenção com sucralfato. MÉTODO: Trinta e seis ratos foram submetidos à colostomia do cólon esquerdo e fístula mucosa distal. Os animais foram divididos em dois grupos de acordo com a eutanásia ser realizada duas ou quatro semanas após a intervenção. Cada grupo foi dividido em três subgrupos de acordo com o tipo de intervenção realizada diariamente: solução salina isolada; sucralfato a 1 g/kg/dia ou sucralfato a 2g/kg/dia. A colite foi diagnosticada por análise histológica adotando escala de validação prévia. A expressão tecidual de ambas as proteínas foi identificada por imunoistoquímica. O conteúdo das proteínas foi quantificado por análise de imagem assistida por computador. RESULTADOS: O escore inflamatório foi maior nos segmentos cólicos sem trânsito fecal e os enemas com sucralfato reduziram o escore inflamatório nesses segmentos, principalmente nos animais submetidos à intervenção com sucralfato em maior concentração e por período mais longo de intervenção. Houve aumento no conteúdo tecidual das proteínas claudina-3 e ocludina, relacionado com a concentração de sucralfato. O conteúdo tecidual de ambas as proteínas não se modificou com a duração da intervenção. CONCLUSÃO: Enemas com sucralfato reduzem a inflamação e aumentam o conteúdo tecidual de claudina-3 e ocludina na mucosa cólica sem trânsito intestinal.

ABSTRACT - BACKGROUND: Oxidative stress is one of the main mechanisms associated with the rupture of the defense mechanisms of the colonic epithelial barrier; it reduces the tissue content of the claudin-3 and occludin proteins, which are the main constituents of intercellular tight junctions. Sucralfate (SCF) has antioxidant activity and has been used to treat different forms of colitis. AIM: This study aimed to measure the tissue claudin-3 and occludin content of the colon mucosa without fecal transit, subjected to intervention with SCF. METHODS: Thirty-six rats were subjected to left colon colostomy and distal mucous fistula. They were divided into two groups according to euthanasia that was performed 2 or 4 weeks after the intervention. Each group was divided into three subgroups according to the enema applied daily: saline alone, SCF at 1 g/kg/day, or SCF at 2 g/kg/day. Colitis was diagnosed by the histological analysis adopting the previous validate scale. The tissue expression of both proteins was identified by immunohistochemical technique. The content of proteins was quantified by computer-assisted image analysis. RESULTS: The inflammatory score was high in colonic segments without fecal transit, and enemas with SCF reduced the inflammatory score in these segments, mainly in those animals submitted to intervention with SCF in greater concentration and for a longer period of intervention. There was an increase in tissue content of claudin-3 and occludin, related to SCF concentration. The tissue content of both proteins was not related to the intervention time. CONCLUSION: Enemas with SCF reduced the inflammation and increased the tissue content of claudin-3 and occludin in colonic mucosa without fecal stream.

ABSTRACT Purpose: To evaluate the effects of sucralfate enemas in tissue contents of E-cadherin and ?-catenin in an experimental diversion colitis. Methods: Thirty-six male Wistar rats were submitted to a proximal colostomy and a distal mucous fistula. They were allocated into three groups: first group received daily saline enemas (2 mL/day) and the two other groups daily enemas with sucralfate at dosage of 1 or 2 g/kg/day, respectively. Six animals of each group were euthanized after two weeks and six animals after four weeks. The inflammation of the excluded mucosa was evaluated by histological analysis. The oxidative damage was quantified by measurement of malondialdehyde tissue levels. The expression of E-cadherin and ?-catenin was identified by immunohistochemistry, and its contents were quantified by computer-assisted image analysis. Results: Sucralfate enemas reduced inflammation in animals subjected to treatment with 2 g/kg/day by four weeks, and the levels of oxidative damage in mucosa without fecal stream irrespective of concentration and time of intervention. E-cadherin and ?-catenin content increased in segments without fecal stream in those animals subjected to treatment with sucralfate. Conclusions: Sucralfate reduces the inflammation and oxidative stress and increases the tissue content of E-cadherin and ?-catenin in colonic mucosa devoid to the fecal stream.

Abstract Purpose: To evaluate the effects of infliximab on the inflammation of the colonic mucosa devoid from fecal stream. Methods: Twenty-four rats were submitted to a Hartmann's procedure. They remained for 12 weeks with the fecal derivation to development of diversion colitis on excluded colorectal stump. After this period, they were divided into 3 groups: one group received intervention with saline (2.0 mL / week), other group infliximab at doses of 5 mg/kg/week and the other 10 mg/kg/week for five consecutively weeks. Concluded the intervention period, the animals were euthanized to remove colon segments with and without fecal stream. Colitis was diagnosed by histological analysis and the degree of inflammation by validated score. The neutrophilic infiltrate was evaluated by tissue expression of myeloperoxidase identified by immunohistochemical. The tissue content of myeloperoxidase was measured by computer-assisted image analysis. Results: The inflammatory score was high in colonic segments without fecal stream. The intervention with infliximab reduced the inflammatory score in excluded colonic segments. The content of myeloperoxidase was reduced in colonic segments of animals treated with infliximab mainly in high concentrations. Conclusion: Intervention with infliximab reduced the inflammation and the neutrophil infiltrate in colonic segments devoid of the fecal stream.

Abstract Purpose: To evaluate the inflammatory reaction and measure the content of mucins, in the colonic mucosa without fecal stream submit to intervention with mesalazine. Methods: Twenty-four rats were submitted to a left colostomy and a distal mucous fistula and divided into two groups according to euthanasia to be performed two or four weeks. Each group was divided into two subgroups according daily application of enemas containing saline or mesalazine at 1.0 g/kg/day. Colitis was diagnosed by histological analysis and the inflammatory reaction by validated score. Acidic mucins and neutral mucins were determined with the alcian-blue and periodic acid of Schiff techniques, respectively. Sulfomucin and sialomucin were identified by high iron diamine-alcian blue technique. The tissue contents of mucins were quantified by computer-assisted image analysis. Mann-Whitney test was used to analyze the results establishing the level of significance of 5%. Results: Enemas with mesalazine in colonic segments without fecal stream decreased the inflammation score and increased the tissue content of all subtypes of mucins. The increase of tissue content of neutral, acid and sulfomucin was related to the time of intervention. Conclusion: Mesalazine enemas reduce the inflammatory process and preserve the content of mucins in colonic mucosa devoid of fecal stream.

RESUMO Objetivo: Verificar se a aplicação de clisteres com extrato oleoso de curcumina preserva o conteúdo de mucinas nas glândulas da mucosa cólica sem trânsito intestinal. Método: Trinta e seis ratos Wistar foram submetidos à derivação intestinal por colostomia proximal e fístula mucosa distal. Os animais foram subdivididos em três grupos, segundo receberem clisteres com soro fisiológico 0,9%, extrato oleoso de curcumina nas concentrações de 50 mg/kg/dia ou 200 mg/kg/dia. Após duas ou quatro semanas de intervenção foram removidos os segmentos cólicos irrigados. As mucinas neutras e ácidas foram identificadas pelas técnicas do PAS e Alcian-Blue, respectivamente. O conteúdo tecidual de ambos os subtipos de mucinas foi mensurado por morfometria computadorizada. Utilizou-se teste de Mann-Whitney para análise dos resultados adotando-se nível de significância de 5% (p ≤ 0,05). Resultados: Houve aumento no conteúdo de mucinas neutras nos animais tratados com curcumina na concentração de 50 mg/kg/dia por quatro semanas, enquanto nos tratados com 200 mg/kg/dia houve aumento independente do tempo de intervenção. O conteúdo de mucinas ácidas aumentou nos animais tratados com 200 mg/kg/dia independente do tempo de intervenção, enquanto nos tratados com 50 mg/kg/dia encontrou-se aumento apenas após quatro semanas. Conclusão: Clisteres com curcumina preservam o conteúdo de mucinas neutras e ácidas no epitélio cólico sem trânsito intestinal.

ABSTRACT Purpose: To verify if the application of enemas containing oily extracts of curcumin preserves the tissue content of mucins in the glands of the colonic mucosa without fecal stream. Method: Thirty-six Wistar rats were submitted to diversion of the fecal stream by proximal colostomy and distal mucous fistula. The animals were subdivided into three groups, and accordingly received enemas with saline and oily extract of curcumin at concentrations of 50 mg/kg/day or 200 mg/kg/day. After two or four weeks of intervention, the irrigated colic segments were removed. Neutral and acidic mucins were identified by Periodic-acid Schiff and Alcian-Blue techniques, respectively. The content of both mucin subtypes was measured by computerized morphometry. Mann-Whitney test was used to analyze the results, adopting a significance level of 5% (p ≤ 0.05). Results: There was an increase in the tissue content of neutral mucins in animals treated with curcumin at a concentration of 50 mg/kg/day for four weeks, whereas in the group treated with 200 mg/kg/day there was an increase independent of the time of intervention. The content of acidic mucins increased in animals treated with 200 mg/kg/day regardless of the intervention time, whereas in those treated with 50 mg/kg/day an increase was observed only after four weeks. Conclusion: Enemas with curcumin preserve the content of neutral and acidic mucins in the colonic epithelium without fecal stream.

RESUMO Racional: Os genes MUTYH e OGG1 possuem importância nos sistemas de reparo por excisão de bases oxidadas do DNA. Modificação na expressão tecidual desses genes encontra-se relacionada ao maior risco do desenvolvimento do câncer colorretal. Objetivo: Avaliar a expressão tecidual dos genes MUTYH e OGG1 comparando tecidos normais e neoplásicos de portadores de câncer colorretal esporádico e correlacioná-la com variáveis clínicas e histopatológicas. Método: Avaliou-se por PCR, em tempo real, a expressão tecidual dos genes MUTYH e OGG1 em 49 portadores de câncer colorretal comparando tecidos normais e neoplásicos. A expressão dos genes MUTYH e OGG1 foi quantificada e normalizada com o gene constitutivo 18S. A intensidade de expressão de ambos os genes foi correlacionada as variáveis: idade, gênero, localização do tumor, tamanho do tumor, tipo histológico, grau de diferenciação celular, profundidade de invasão na parede intestinal, invasão angiolinfática, linfonodos comprometidos e estadiamento TNM. Resultados: Encontrou-se menor expressão de ambos os genes no tecido neoplásico quando comparado ao tecido normal. Houve menor expressão do gene MUTYH nos tumores com maiores dimensões e nos doentes que apresentavam invasão angiolinfática. Tumores com estadios mais avançados (III e IV) apresentavam expressão menor de ambos os genes quando comparados àqueles com estadios mais precoces (I e II). Conclusão: Os genes MUTYH e OGG1 apresentam menor expressão tecidual nos estadios mais avançados do câncer colorretal.

ABSTRACT Background: MTUYH and OGG1 genes have importance in the base excision repair systems of oxidized DNA bases. Modification of the tissue expression of these genes is related to the increased risk of developing colorectal cancer. Aim: To evaluate the tissue expression of MUTYH and OGG1 comparing normal and neoplastic tissues of patients with sporadic colorectal cancer and to correlate it with clinical and histopathological variables. Method: MUTYH and OGG1 tissue expression was quantified by RT-PCR in patients with colorectal cancer and the values were compared in normal and neoplastic tissues. MUTYH and OGG1 expression was measured and normalized to the constitutive 18S gene. The level of expression of both genes was correlated with the variables: age, gender, tumor location, size of the tumor, histological type, degree of cell differentiation, invasion depth in the intestinal wall, angiolymphatic infiltration, lymph node involvement and TNM staging. Results: Was found downregulation of both genes in neoplastic when compared to normal tissue. There was downregulation of the MUTYH in larger tumors and in patients with angiolymphatic invasion. Tumors with more advanced TNM stages (III and IV) presented downregulation of both genes when compared to those with earlier stages (I and II). Conclusion: The MUTYH and OGG1 genes present downregulation in the more advanced stages of colorectal cancer.

Abstract Purpose: To evaluate the inflammatory intensity and measure the tissue content of the proteins claudin-3 and occludin in the colonic mucosa without fecal stream submit to intervention with curcumin. Methods: Thirty-six rats were submitted to a proximal colostomy and a distal mucous fistula and divided into two groups according to sacrifice to be performed two or four weeks. Each group was divided into three subgroups according daily application of enemas containing saline, curcumin at 50 mg/kg/day or 200 mg/kg/day. Colitis was diagnosed by histological analysis. Claudin-3 and occludin were determined by immunohistochemistry. The tissue content of claudin-3 and occludin were quantified by computer-assisted image analysis. Mann-Whitney, Student t and ANOVA tests were used to analyze the results establishing the level of significance of 5% for both (p<0.05). Results: Curcumin at both concentrations reduces the inflammation and preserves the tissue content of the proteins claudin-3 and occludin, which was related to the concentration used and to the time of the intervention. Conclusion: The application of enemas with curcumin reduces inflammation and preserves the tissue content of the proteins claudin-3 and occludin in the colonic mucosa devoid from the fecal stream.

Objetivo: Avaliar os efeitos anti-inflamatórios e antioxidantes do SCF em modelo de colite de exclusão. Método: Trinta e seis ratos, foram submetidos a derivação intestinal por colostomia terminal no cólon descendente e fistula mucosa distal. Os animais foram divididos em 3 grupos experimentais segundo receberem clisteres diários com SF 0,9%, SCF 1 g/kg/dia ou SCF 2 g/kg/dia. Cada grupo foi dividido em dois subgrupos segundo a eutanásia ser realizada após 2 ou 4 semanas da derivação. O grau de inflamação tecidual foi avaliado por estudo histológico e a infiltração neutrofílica pela expressão tecidual de mieloperoxidase (MPO) identificada por imunoistoquímica e quantificada por morfometria computadorizada. O estresse oxidativo foi mensurado pelo conteúdo de malondialdeído (MDA). Para análise dos resultados utilizou-se os teste t de Student, e ANOVA, estabelecendo-se para todos os testes nível de significância de 5% (p < 0,05). Resultados: A intervenção com SCF melhorou o grau de inflamação tecidual relacionando-se a concentração utilizada e ao tempo de intervenção. A intervenção com SCF reduziu os níveis teciduais de MPO, independente da concentração ou do tempo de intervenção (p < 0,01). Houve redução dos níveis de MDA nos animais irrigados com SCF, independente da concentração ou tempo de intervenção (p < 0,01). Conclusão: Enemas com SCF reduzem o processo inflamatório, infiltrado neutrofílico e estresse oxidativo no cólon excluso sugerindo que a substância possa se tornar uma opção terapêutica válida para o tratamento da colite de exclusão.

Objective: To evaluate the anti-inflammatory and antioxidant effects of sucralfate enemas in diversion colitis model. Method: Thirty-six Wistar rats underwent intestinal bypass by end colostomy in the descending colon and distal mucous fistula. The animals were divided into 3 experimental groups according to the daily dose of enemas received containing 0.9% SF, sucralfate enemas or sucralfate enemas 1 g/kg/day or 2 g/kg/day. Each group was divided into two subgroups according to euthanasia to be performed 2-4 weeks after derivation. The tissue grade of inflammation was assessed histologically, and neutrophil infiltration by the tissue expression of myeloperoxidase (MPO) identified by immunohistochemistry and quantified by computerized morphometry. Oxidative stress was measured by tissue levels of malondialdehyde (MDA). To compare the results the Student's t test variance was used, and also the variance by ANOVA test, establishing a level of significance of 5% (p < 0.05) for both. Results: The intervention with sucralfate enemas showed improvement in the intensity of tissue inflammation related to the concentration used and the duration of the intervention. Intervention with sucralfate enemas reduced the tissue levels of MPO, independent of concentration or time of intervention (p < 0.01). There was a reduction of MDA levels in animals irrigated with sucralfate enemas, independent of concentration or duration of the intervention (p < 0.01). Conclusion: Enemas with sucralfate enemas reduce inflammation, neutrophil infiltration and oxidative stress in the excluded colon suggesting topical application of the substance to be a valid therapeutic option for the treatment of diversion colitis.