Período de absorção intestinal de macromoléculas em cabritos recém-nascidos após a ingestão de colostro bovino / Macromolecules intestinal absorption period of goat kids after bovine colostrum intake

Após o nascimento, os cabritos são dependentes das imunoglobulinas colostrais devido às características placentárias que não permitem a passagem de macromoléculas da circulação materna. De acordo com a literatura, os cabritos possuem capacidade absortiva por até quatro dias. Muitos aspectos fisiológicos de outras espécies são aceitos e utilizados para caprinos, mas aqueles relacionados à transferência de imunidade passiva precisam de investigação. Os objetivos do presente estudo foram determinar o período de passagem de macromoléculas da mucosa intestinal para a circulação e a duração da proteção humoral transferida passivamente pela ingestão de colostro bovino e caprino. Sessenta cabritos recém-nascidos foram distribuídos em seis tratamentos: T 0 (n=25), ingestão natural de colostro caprino à vontade; T 1 (n=7), colostro bovino entre o nascimento e duas horas pós-parto; T 2 (n=7), ingestão de colostro bovino entre quatro e seis horas pós-nascimento; T 3 (n=7), leite nas primeiras oito horas e colostro bovino entre 10 e 12 horas pós-parto; T 4 (n=7), ingestão de leite até 18 horas e colostro bovino entre 22 e 24 horas pós-nascimento; T 5 (n=7), leite até 30 horas e ingestão de colostro bovino entre 34 e 36 horas pós-parto. Determinaram-se as concentrações séricas de proteína total (PT), gamaglobulina, imunoglobulina G (IgG) e a atividade sérica de gama glutamiltransferase (GGT). Ao nascimento, todos os neonatos tiveram valores mais baixos das variáveis, com aumento significativo da PT e gamaglobulina, após dois dias, nos grupos T 0, T 1 e T 2; a IgG e GGT aumentaram em todos os grupos. Os tratamentos T 3, T 4 e T 5 foram considerados como indutores de falha de transferência de imunidade passiva. A absorção de macromoléculas pelo trato intestinal dos cabritos ocorreu até 36 horas pós-parto, sendo mais efetiva até 12 horas. Os níveis de anticorpos persistiram até 75 dias após a ingestão de colostro bovino, porém, com concentrações inadequadas.

After birth goat kids are dependent of colostrum immunoglobulins due to placental characteristics that don't allow macromolecules passage from dam's circulation. According to literature goat kids have colostrum immunoglobulin absorption capability for up to four days. Many physiological aspects of other species have been accepted and used for goats, but those related to passive immunity transference needs more investigation. The goals of the present study was to determine the period of macromolecules passage through gut wall to circulation until 36 hours postpartum and verify the duration of protective humoral immunity transferred by the ingestion of bovine and caprine colostrum. Sixty newborn goat kids were allocated into six treatment groups: T 0 (n=25), non-restricted natural ingestion of goat colostrum; T 1 (n=7), bovine colostrum from birth to two hours postpartum; T 2 (n=7), bovine colostrum ingestion between four to six hours after birth; T 3 (n=7), milk intake until the first eight hours and bovine colostrum administration between 10 to 12 hours postpartum; T 4 (n=7), milk ingestion for the first 18 hours and bovine colostrum ingestion between 22 and 24 hours after birth; T 5 (n=7), milk administration until 30 hours and bovine colostrum intake between 34 to 36 hours postpartum. The total protein (TP), gammaglobulin, immunoglobulin G (IgG) and gamma-glutamyltransferase (GGT) serum concentrations were determined. At birth all neonates presented lower values of the variables, with significant increase of TP and gammaglobulin at two days in groups T 0, T 1 and T 2, IgG and GGT increased in all groups. The treatments T 3, T 4 and T 5 were considered to induce failure of immunity passive transfer. The absorption of macromolecules by kid's intestinal tract occurred until 36 hours postpartum, with better effectiveness until 12 hours. Antibody levels persist up to 75 days after bovine colostrum intake, but at this time their low concentrations doesn't provide adequate protection.

Cell proliferation of the ileum intestinal mucosa of diabetic rats treated with ascorbic acid

The objective of this work was to evaluate the effect of the ascorbic acid supplementation on the cellular proliferation on the ileum mucosa of diabetic rats. Fifteen 90-days rats were divided in the groups: control, diabetic and diabetic supplemented with ascorbic acid (DA). Two hours prior the sacrifice, they were injected with Vincristin. Semi-seriate histological cuts stained with HE were accomplished. About 2500 crypt cells from the intestinal mucosa were counted in order to obtain the metaphasic indexes. The height and depth of 30 villi and 30 crypts were measured for each animal, respectively. The metaphasic indexes showed no significant changes when we compared the three groups: 20.2 +/- 0.7 (control), 18 +/- 1.9 (diabetic) and 17 +/- 1.4 (DA) (p > 0.05). The values obtained from the crypts measurement were 221.2 +/- 8.5 (control), 225.3 +/- 9.5 (diabetic) and 222 +/- 34 (DA). The villi of the control, diabetic and DA animals presented the following results: 301.7 +/- 25.33, 304.8 +/- 25.63 and 322.1 +/- 45.77 respectively. The morphometric data were not different statistically (p > 0.05). Summing up, the present work showed that there was no alteration in the cellular proliferation of the ileum of diabetic-induced rats supplemented with ascorbic acid.

Avaliação morfométrica da mucosa do intestino grosso após derivação jejunoileal em ratos / Large bowell morphometric analysis after jejunoileal bypass in rats

A epidemia mundial de sobrepeso e obesidade é estimada atingir 1,7 bilhões de pessoas e atualmente, a cirurgia oferece boa opção de tratamento com perda de peso sustentada para o obeso mórbido. Aproximadamente 70 por cento dos procedimentos bariátricos realizados hoje apresenta algum componente disabsortivo...

The world epidemic of overweight and obesity is estimated to encompass about 1,7 billion individuals and currently, surgery offers the only viable treatment option with longterm weight loss and maintenance for the morbidly obese. Almost 70 per cent of the bariatric procedures performed today offers the patient some defree of disabsorption...

Barrera intestinal del paciente crítico: realidades y tendencias / Gut barrier in the critically ill patient: facts and trends

The disturbances of gut barrier in critically ill patients may influence their outcome and prognosis. Experiments in animals show that fasting and stress collaborate to produce intestinal atrophy and translocation of microorganisms and toxins. This fact is one of the main arguments to promote the use of early enteral feeding in critically ill patients. However, the intestinal barrier behaves differently in humans than in animals. The human enteral cells have a good tolerance to fasting and stress, mucosal atrophy is mild and it is not always associated with changes in intestinal permeability. Moreover, the relationship between intestinal permeability with sepsis and bacterial translocation is controversial. This last phenomenon also happens in normal subjects and may be a mechanism to build immunological memory. One of the most important factors that influence bacterial translocation is the microorganism, that under stress conditions can adhere to the intestinal cell and penetrate the intestinal barrier. Splanchnic ischemia and reperfusion is one of the main pathogenic factors in the failure of intestinal barrier. Finally, the fact that the small bowel is an inflammatory target of extra intestinal injuries, explains several clinical situations. The pathophysiology of the intestinal barrier definitely requires more research.

Prevention of bacterial translocation using beta-(1-3)-D-glucan in small bowel ischemia and reperfusion in rats

PURPOSE: To investigate the role of beta-(1-3)-D-glucan on 99mTc labelled Escherichia coli translocation and cytokines secretion in rats submitted to small bowel ischemia/reperfusion injury. METHODS: Five groups (n=10 each) of Wistar rats were subjected to control(C), sham(S), group IR subjected to 45 min of bowel ischemia/60 min of reperfusion(I/R), and group I/R+glucan subjected to 45 min of bowel ischemia/60 min of reperfusion(I/R) and injected with 2mg/Kg intramuscular. Translocation of labelled bacteria to mesenteric lymph nodes, liver, spleen, lung and serum was determined using radioactivity/count and colony forming units/g(CFU/g). Serum TNFalpha, IL-1beta, IL-6, IL-10 were measured by ELISA. RESULTS: CFU/g and radioactivity/count were higher in I/R than in I/R+glucan rats. In C, S and S+glucan groups, bacteria and radioactivity/count were rarely detected. The I/R+glucan rats had enhancement of IL-10 and suppressed production of serum TNFalpha, IL-1beta and, IL-6, compared to I/R untreated animals. CONCLUSION: The beta-(1-3)-D-glucan modulated the production of pro-inflammatory and anti-inflammatory cytokines during bowel ischemia/reperfusion, and attenuated translocation of labelled bacteria.

OBJETIVO: Investigar o papel da beta-(1-3)-D-glucana na translocação de Escherichia coli marcada com 99mTc e na secreção de citocinas em ratos submetidos a isquemia e reperfusão intestinal. MÉTODOS: Cinco grupos (n=10 cada) de ratos Wistar foram denominados controle (C), sham (S), grupo IR submetido a 45 minutos de isquemia do intestino delgado e 60 minutos de reperfusão(I/R), grupo I/R+glucana com 45 minutos de isquemia e 60 minutos de reperfusão(I/R) e tratados com glucana 2mg/Kg intramuscular. Translocação de Escherichia coli marcada com 99mTc, para Linfonodos mesentéricos, fígado, baço, pulmão e soro foi avaliada usando contagem de radioatividade e de unidades formadoras de colônias/g (UFC/g) Dosagem sérica de TNFalfa, IL-1beta, IL-6, IL-10 foi realizada pelo método ELISA. RESULTADOS: CFU/g e contagem de radioatividade foi significantemente maior nos ratos do grupo I/R do que no grupo I/R+glucana. Nos grupos C, S e S+glucana bactérias e contagem radioativa foram raramente detectadas. Os ratos do grupo I/R+glucana tiveram aumento de IL-10 sérica e significante redução da expressão de TNFalfa, IL-1beta e IL-6, quando comparados com os animais não tratados do grupo I/R. CONCLUSÃO: A beta-(1-3)-D-glucana modulou a produção de citocinas pró-inflamatórias e anti-inflamatórias durante a isquemia/reperfusão intestinal e contribuiu para reduzir a translocação de bactérias marcadas.

Mucosal Restitution / 대한소화기학회지

The repair of superficially damaged intestinal epithelium is initiated by restitution. Restitution is the covering of damaged area by the movement of neighboring epithelial cells without cell proliferation. Phenotypic switching of cells (epithelial-mesenchymal transition) is necessary for the cell movement and this process is controlled by complex intracellular signaling pathways conducting dynamic remodeling of actin cytoskeleton. Restitution is regulated by a variety of cytokines and growth factors, and is modulated by integrin-dependent interactions with the extracellular matrix. Understanding the restitution process suggests several possible therapeutic strategies to enhance gastrointestinal wound healing.

Mucosal Restitution / 대한소화기학회지

The repair of superficially damaged intestinal epithelium is initiated by restitution. Restitution is the covering of damaged area by the movement of neighboring epithelial cells without cell proliferation. Phenotypic switching of cells (epithelial-mesenchymal transition) is necessary for the cell movement and this process is controlled by complex intracellular signaling pathways conducting dynamic remodeling of actin cytoskeleton. Restitution is regulated by a variety of cytokines and growth factors, and is modulated by integrin-dependent interactions with the extracellular matrix. Understanding the restitution process suggests several possible therapeutic strategies to enhance gastrointestinal wound healing.

Epithelial effects of proteinase-activated receptors in the gastrointestinal tract

The intestinal epithelium plays a crucial role in providing a barrier between the external environment and the internal milieu of the body. A compromised mucosal barrier is characteristic of mucosal inflammation and is a key determinant of the development of intestinal diseases such as Crohn's disease and ulcerative colitis. The intestinal epithelium is regularly exposed to serine proteinases and this exposure is enhanced in numerous disease states. Thus, it is important to understand how proteinase-activated receptors (PARs), which are activated by serine proteinases, can affect intestinal epithelial function. This review surveys the data which demonstrate the wide distribution of PARs, particularly PAR-1 and PAR-2, in the gastrointestinal tract and accessory organs, focusing on the epithelium and those cells which communicate with the epithelium to affect its function. PARs have a role in regulating secretion by epithelia of the salivary glands, stomach, pancreas and intestine. In addition, PARs located on subepithelial nerves, fibroblasts and mast cells have important implications for epithelial function. Recent data outline the importance of the cellular site of PAR expression, as PARs expressed on epithelia may have effects that are countered by PARs expressed on other cell types. Finally, PARs and their ability to promote epithelial cell proliferation are discussed in terms of colon cancer.

Vestibulo-cerebellar participation in protection of duodenal mucosa: possible role of neurotransmitters.

Vestibulo cerebellar lesion in rats produced a decrease in the intracellular presecreted mucus together with a decrease in the norepinephrine (NE) and serotonin (5HT) content of the duodenal tissue. Whereas vestibulo cerebellar stimulation by rotation produced an increase in the intracellular presecreted mucus and an increase in the NE content of the duodenal tissue but very little increase in 5HT content of the duodenum. The results suggest that the vestibulo cerebellum by modulating the tissue content of the neurotransmitter NE and 5HT has a direct influence in the protective mechanism through the intracellular mucus content.

Gluten-free diet improves iron-deficiency anaemia in patients with coeliac disease.

Two cases of newly-diagnosed asymptomatic coeliac disease with 3 years of unexplained severe iron-deficiency anaemia are presented. Oral iron supplementation had no effect on their serum iron levels and, therefore, had no influence on their anaemia. Upper gastrointestinal endoscopy confirmed normal macroscopic findings. Duodenal biopsies revealed subtotal villous atrophy of the mucosa of the small intestine. A strict gluten-free diet led to an increase in serum iron, resolution of anaemia, and restitution of normal mucosal morphology. Thus, severe iron-deficiency anaemia associated with asymptomatic coeliac disease is responsible to gluten-free diet.

Estudo da transmigração bacteriana na apendicite experimental em coelhos / Study about bacterial transmigration in experimental appendicitis in rabbits

Introdução: A queda extrínseca dos mecanismos de defesa de um hospedeiro é vista classicamente como uma infecção, que resulta na aquisição de um tecido normal, de um novo microorganismo, cuja virulência é fundamental para a sua patogenia.Na década de 50, estudos comprovaram que bactérias e endotoxinas podem ultrapassar a barreira intestinal e atingir a circulação, demonstrando ainda, que a flora intestinal representa uma importante fonte para o desenvolvimento da infecção sistêmica. Objetivo: o presente estudo visa avaliar a ocorrência de transmigração bacteriana em apendicite experimental induzida em coelhos, mediante a oclusão completa do apêndice vermiforme. Métodos: foram utilizados 24 coelhos brancos, da linhagem Nova Zelândia, com peso corporal variando de 2500 a 3000 gramas, sendo então divididos em 2 grupos. Os animais do Grupo I foram submetidos a laparotomia mediana e retirada de fragmentos do baço, rim esquerdo, pulmão direito, linfonodo abdominal, conteúdo da luz do apêndice vermiforme e sangue da veia porta para cultura. Os animais do Grupo II foram submetidos a laparotomia mediana e oclusão completa do apêndice vermiforme para a indução de apendicite e, após 24 horas, realizada a coleta do material nos moldes do Grupo I. Resultados: No Grupo controle (Grupo I), não se observou o crescimento de bactérias nas amostras analisadas. No Grupo experimento (Grupo II), observou-se o crescimento de Escherichia coli em todos os animais. Conclusão: Ocorreu transmigração bacteriana após 24 horas de observação em coelhos com apendicite experimental.

Cell proliferation and migration in the jejunum of suckling rats submitted to progressive fasting

Cell proliferation and migration in the intestinal crypts, and cell migration in the villus are controlled by different mechanisms in adult rats. In the present study, weanling rats and fasting rats were used to quantitatively study the correlation of cell cycle parameters and epithelial cell migration in crypts and intestinal villi. Eighteen-day-old rats received a single injection of tritiated thymidine[3H]T dR (23:00 h); half of the pups were submitted to fasting 5 h earlier. Cell proliferation was determined in radioautographs of jejunal crypts, on the basis of the labeling indices (LI) taken 1,8,13 and 19 h after [3H]TdR. The results showed that the labeling index did not differ 1 h or 19 h after [3H]TdR between the fed (38.7 percent or 48 percent) and fasting groups (34.6 percent or 50.4 percent). The modified method of grain count halving indicated that cell cycle time did not differ between fed (16.5 h) and fasting rats (17.8 h); the growth fraction, however, had lower values in fasting (59 percent) than in fed rats (77 percent). Cell migration in the crypt, estimated by the LI obtained for each cell position, did not change with treatment. As for the villi, the cell migration rate was significantly retarded by 3 cell positions (8 percent). These results suggest that the cell migration in the villi of weanling pups does not depend directly on the cell proliferation and migration in the intestinal crypt, but is directly affected by the absence of food in the lumen.

Omental plug closure of large duodenal defects--an experimental study.

This study was conducted to evaluate the efficacy of omental plugging in the management of large duodenal defects and analyse the serial histopathological changes occurring in the omental plug and the edges of the defect until healing occurred as evidenced by complete mucosal cover. The study was conducted in 12 dogs. Through a laparotomy wound a 20 mm diameter defect was created in the first part of the duodenum. The abdomen was closed, leaving the defect open, for a period of three hours to allow peritonitis to set in. Subsequently the abdomen was reopened and the perforation was plugged with omentum pulled into the duodenal lumen and fixed to the edges. They were randomly sacrificed two at a time on the first week, second week, fourth week, sixth week and eight week post operatively. The morphology of the perforation site, adequacy of the duodenal lumen, and the histological picture at each stage were studied. There was no morbidity except in one dog which showed signs of high intestinal obstruction that resolved after conservative management. There was one mortality due to sepsis unrelated to the procedure. The omentum was firmly adherent and there was no evidence of leak from the site of closure. The omental plug underwent inflammation, necrotic changes, granulation, reduction in size and fibrosis. The defects decreased rapidly in size and healing was complete at eight weeks with the mucosa taking a normal histological appearance. None of the dogs exhibited luminal obstruction on autopsy. This study reaffirms the reliability of the omental plug in safely occluding large duodenal defects and producing healing through a process of inflammation, granulation, vascularisation and fibrosis eventually providing a normal duodenal mucosal cover to the perforation site.

Esvaziamento gástrico de sacarose e maltose e os níveis das respectivas dissacaridases na mucosa do intestino delgado de ratos adultos / Gastric emptying of sucrose and maltose and the activities of respective disaccharidases in the intestinal mucosa of adult rats

O esvaziamento gástrico (EG) de soluçöes de sacarose e de maltose em diferentes concentraçöes, marcadas com fenol vermelho (6mg por cento), foi determinado em 144 ratos Wistar machos. Foi avaliada a retençäo gástrica (RG), após 15 minutos da infusäo orogástrica, de soluçöes de sacarose e de maltose nas concentraçöes de 2,5 por cento, 5 por cento e 10 por cento, empregado inicialmente 1 ml e noutra observaçäo 2 ml/100 g de peso do animal. Para cada volume e concentraçäo foram utilizados 12 animais. Foram determinadas as atividades das dissacridases, lactase, sacarase e maltase no intestino delgado de outros oito ratos Wistar machos, submetidos às mesmas condiçöes do estudo. Os resultados mostrarom uma relaçäo da atividade da maltose com a da atividade da maltose com a da sacarose de 4:1. Por outro lado, a RG das soluçöes de maltose a 5 por cento e 10 por cento foi significativamente maior que a de sacarose nas mesmas concentraçöes, independente do volume utilizado. Em concentraçäo a 2,5 por cento näo houve diferença significativa entre as RG das duas soluçöes. Para explicar os resultados, é proposto que o EG mais rápido da soluçäo de sacarose nas concentraçöes a 5 por cento e 10 por cento comparado à soluçäo de maltose nas mesmas concentraçöes, resulta de uma possível saturaçäo da sacarose, com interrupçäo na regulaçäo do EG, gerada a partir de receptores intestinais

Estudo comparativo do esvaziamento gástrico de dissacarídios e de seus respectivos monossacarídios em ratos com deficiência ontogênica de lactase / Comparative study of the gastric emptying of disaccharides and their respective monosaccharides in rats with ontogenic lactase deficiency

Com a finalidade de avaliar o esvaziamento gástrico de dissacarídios e monossacarídios, foram empregados no estudo 64 ratos Wistar, machos, pesando, em média, 180g. com idade de 8-10 semanas de vida, divididos em grupos de oito animais cada. Os grupos foram assim constituídos: grupo maltose, grupo sacarose, grupo lactose e grupo lactulose e os correspondentes grupos de monossacarídios: grupos glicose, grupo frutose + glicose, grupo galactose + glicose e grupo galactose + frutose. Cada animal de cada grupo recebeu, por via orogástrica, após jejum alimentar de 20h, refeiçäo de prova constituída de uma soluçäo a 10% (p/v) de açucar, acrescida de fenol vermelho na concentraçäo de 6mg/dl, como marcador. O volume empregado foi de 2ml/100g de peso do animal. A retençäo gástrica foi determinada aos 10 min após infusäo da refeiçäo de prova, e expressa em porcentagem. Os resultados (X ñ SE) das retençöes gástricas (%) da sacarose (35,0ñ 1,8), lactose (30,4 ñ 1,5) e lactulose (29,5 ñ 1,6 foram significativamente menores (teste t, alfa = 0,05) que os observados com os respectivos monossacarídios, ou seja, glicose + frutose (46,9 ñ 2,6), glicose + galactose (48,3 ñ 2,4), galactose + frutose (43,5 ñ 1,5). Näo foi observada diferença da retençäo gástrica de maltose (49,0 ñ 4,7), quando comparada com a glicose (53,0 ñ 3,0). Entre os dissacarídios, a análise estatístoca (análise de variância seguida do teste de Tukey, alfa = 0,05) dos resultados näo mostrou diferenças na retençäo gástrica de sacarose, lactose e lactulose. A retençäo gástrica da maltose foi significativamente maior em relaçäo aos outros dissacarídios. Näo foram observadas diferenças significativas na retençäo gástrica dos monossacarídios. Estas observaçöes indicam que a menor concentraçäo de dissacaridases (sacarase, lactase) ou aausência de uma enzima específica (lactulase), na mucosa do intestino delgado, induz um esvaziamento gástrico mais rápido dos respectivos dissacarídios. O fenômeno pode ser explicado pela falta de estímulo dos receptores que modulam o esvaziamento gástrico, lcoalizados mais profundamente em relaçäo às enzimas

A propósito da renovaçäo do epitélio intestinal: II. Fatores intraluminais, sistêmico, influências neurovasculares e adaptaçäo pós-operatório, no cólon / Renewal of colonic intestinal epithelium: II. Action of intraluminal, systemic, neurovascular factors and postoperative adaptation

Vários estudos têm sido realizados com o objetivo de melhor determinar os múltiplos mecanismos envolvidos no precesso de renovaçäo do epitélio intestinal. Alguns fatores säo conhecidamente participantes deste fenômeno. Entretanto, existem inúmeras pesquisas com resultados contraditórios sobre o assunto, especialmente no que se refere ao cólon. Os autores fazem uma análise comparativa da participaçäo dos principais fatores atuantes no processo da renovaçäo epitelial colônica, associando condiçöes fisiológicas e/ou patológicas. O objetivo é para tentar elucidar algumas dúvidas, entre as inúmeras existentes, para melhor compreensäo de certas entidades mórbidas que, de maneira contumaz, assentam-se no intestino grosso