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ABSTRACT Purpose: To evaluate the effects of the experimental subcutaneous Walker-256 tumor and L-glutamine supplementation, an antioxidant, on the glomerular morphology of rats. Methods: Twenty Wistar rats were distributed into four groups (n = 5): control (C); control treated with 2% L-glutamine (CG); rats with Walker-256 tumor (WT); and rats with Walker-256 tumor treated with 2% L-glutamine (WTG). Renal histological samples were submitted to periodic acid-Schiff and Masson’s Trichrome staining to analyze glomerular density, morphometry of glomerular components and glomerulosclerosis; and to immunohistochemistry for fibroblast growth factor-2 (FGF-2). Results: WT showed 50% reduction in body mass gain and cachexia index > 10%, while WTG demonstrated reduction in cachexia (p < 0.05). WT revealed reduction of glomerular density, increase in the glomerular tuft area, mesangial area, matrix in the glomerular tuft, decrease in the urinary space and synechia, and consequently higher glomerulosclerosis (p < 0.05). L-glutamine supplementation in the WTG improved glomerular density, and reduced glomerular tuft area, urinary space, mesangial area, and glomerulosclerosis compared to WT(p < 0.05). WT showed higher collagen area and FGF-2 expression compared to C (p < 0.05). WTG presented lower collagen fibers and FGF-2 expression compared to WT (p < 0.05). Conclusions: L-glutamine supplementation reduced cachexia and was beneficial for glomerular morphology of the rats, as well as it reduced kidney damage and improved the remaining glomeruli morphology.

Erectile dysfunction is caused due to neuropathy, resulting from a high oxidative stress, in this way treatment with antioxidants may be promising. Aim of this work was to investigate the effects of the administration of 2% L-glutamine and 1% L-glutathione on the penile tissue of diabetic rats analyzing the nerve fibers that expressing Nitric Oxide Synthase Neuronal (nNOS). Forty-eight male Wistar rats distributed into six groups were used: normoglycemic, diabetic, normoglycemic administered with 2% L-glutamine, normoglycemic administered with 1% L-glutathione, diabetic administered with 2% L-glutamine, and diabetic administered with 1% L-glutathione. After a 120 days experimental period, the animals were euthanized, and the penile tissues were collected and processed for the subsequent immunohistochemical procedure (nNOS) and posterior varicosities morphometry analysis. Diabetic rats administered with L-glutamine and with L-glutathione displayed larger varicosity areas of 14 and 15% compared to the diabetic group (p < 0.05). On the other hand, the administration of 2% L-glutamine and 1% L-glutathione in normoglycemic animals promoted a reduction of 3.3% and 2.4% compared to the normoglycemic group (p < 0.05). We concluded that both L-glutamine and L-glutathione administrations exerted a protective effect on the penile nitrergic innervation of diabetic rats, which can have a positive impact on the erectile function and that their use in normoglycemic animals should be better investigated.

This study aimed to analyze the effects of the quercetin (100 mg/kg), 1% glutamine and 1% α-tocopherol antioxidants in the myocardium of rats with streptozotocin-induced diabetes mellitus. Twenty male rats were subdivided into four groups (n = 5): N (normoglycemic); D (diabetic); NT (normoglycemic treated with antioxidants); and DT (diabetic treated with antioxidants) treated for 60 days. Clinical parameters, oxidative stress markers, inflammatory cytokines, myocardial collagen fibers and immunoexpression of superoxide dismutase 1 (SOD-1), glutathione peroxidase-1 (GPx-1), interleukin-1β (IL-1-β), transforming growth factor-beta (TGF-β), and fibroblast growth factor-2 (FGF-2) were evaluated. Results showed reduced body weight, hyperphagia, polydipsia and hyperglycemic state in groups D and DT. The levels of glutathione (GSH) were higher in NT and DT compared to N (p

ABSTRACT BACKGROUND: Serotonin (5-HT) is present in the epithelial enterochromaffin cells (EC), mast cells of the lamina propria and enteric neurons. The 5-HT is involved in regulating motility, secretion, gut sensation, immune system and inflammation. OBJECTIVE: Evaluate the effects of diabetes and quercetin supplementation on serotoninergic cells and its cell loss by apoptosis in jejunal mucosa of streptozotocin-induced diabetic rats (STZ-rats). METHODS: Twenty-four male Wistar rats were divided into four groups: normoglycemic (C), normoglycemic supplemented with 40 mg/day quercetin (Q), diabetic (D) and diabetic supplemented with 40 mg/day quercetin (DQ). After 120 days, the jejunum was collected and fixated in Zamboni’s solution for 18 h. After obtaining cryosections, immunohistochemistry was performed to label 5-HT and caspase-3. Quantification of 5-HT and caspase-3 immunoreactive (IR) cells in the lamina propria, villi and crypts were performed. RESULTS: The diabetic condition displayed an increase of the number of 5-HT-IR cells in villi and crypts, while decreased number of these cells was observed in lamina propria in the jejunum of STZ-rats. In the diabetic animals, an increased density of apoptotic cells in epithelial villi and crypts of the jejunum was observed, whereas a decreased number of caspase-3-IR cells was observed in lamina propria. Possibly, quercetin supplementation slightly suppressed the apoptosis phenomena in the epithelial villi and crypts of the STZ-rats, however the opposite effect was observed on the 5-HT-IR cells of the lamina propria. Quercetin supplementation on healthy animals promoted few changes of serotoninergic function and apoptotic stimuli. CONCLUSION: These results suggest that quercetin supplementation mostly improved the serotonergic function affected by diabetes maybe due to antioxidant and anti-inflammatory properties of quercetin.

Recent studies have been evaluating the presence of patterns associated with the occurrence of cancer in different types of tissue present in the individual affected by the disease. In this article, we describe preliminary results for the automatic detection of cancer (Walker 256 tumor) in laboratory animals using preclinical microphotograph images of the subject’s liver tissue. In the proposed approach, two different types of descriptors were explored to capture texture properties from the images, and we also evaluated the complementarity between them. The first texture descriptor experimented is the widely known Local Phase Quantization (LPQ), which is a descriptor based on spectral information. The second one is built by the application of a granulometry given by a family of morphological filters. For classification, we have evaluated the algorithms Support Vector Machine (SVM), k-Nearest Neighbor (k-NN) and Logistic Regression. Experiments carried out on a carefully curated dataset developed by the Enteric Neural Plasticity Laboratory of the State University of Maringá showed that both texture descriptors provide good results in this scenario. The accuracy rates obtained using the SVM classifier were 96.67% for the texture operator based on granulometry and 91.16% for the LPQ operator. The dataset was made available also as a contribution of this work. In addition, it is important to remark that the best overall result was obtained by combining classifiers created using both descriptors in a late fusion strategy, achieving an accuracy of 99.16%. The results obtained show that it is possible to automatically perform the identification of cancer in laboratory animals by exploring texture properties found on the tissue taken from the liver. Moreover, we observed a high level of complementarity between the classifiers created using LPQ and granulometry properties in the application addressed here.

Background/Aims: Trichilia catigua A. Juss., known as “catuaba” in Brazil, has been popularly used as a tonic for fatigue, impotence and memory deficits. Previously, our group demonstrated that the ethyl-acetate fraction (EAF) of T. catigua has antioxidant and anti-inflammatory effects. The present study evaluated the anti-diabetic activity of EAF in type 1 diabetic rats. Methods: Male Wistar rats were divided into four groups (N: non-diabetic group, D: type 1 diabetic group, NC: non-diabetic + EAF group and DC: type 1 diabetic + EAF group). The latter two groups were treated with 200 mg/kg EAF. Type 1 diabetes was induced by intravenous streptozotocin (STZ) injection (35 mg/kg). Starting two days after STZ injection, EAF was administered daily by gavage for 8 weeks. Results: EAF attenuated body mass loss and reduced food and water intake. EAF improved hyperglycaemia and other biochemical parameters, such as alkaline phosphatase (ALP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Furthermore, the number of pancreatic β-cells and the size of the islets had increased by β-cell proliferation in the DC group. EAF promoted reduction in kidney tissue damage in STZ-induced diabetic rats by reduction of renal fibrosis. Conclusion: The present study showed that EAF improves glucose homeostasis and endocrine pancreas morphology and inhibits the development of diabetic nephropathy in STZ-induced diabetic rats.

Abstract Ingested fluoride (F) is absorbed mainly in the small intestine, which is controlled by the Enteric Nervous System (ENS). Although important intestinal symptomatology has been described after excessive F exposure, there have been no studies reporting the effects of F on the ENS. In this study, the effects of chronic F exposure were evaluated on the duodenums of rats through proteomic and morphological analyses. Concentrations of 0, 10, or 50 ppm of F were applied to the drinking water for 30 days. Immunofluorescence techniques were performed in the myenteric plexus of the duodenum to detect HuC/D, neuronal nitric oxide (nNOS), vasoactive intestinal peptide (VIP), calcitonin gene related peptide (CGRP), and substance P (SP). The 50 ppm F group presented a significant decrease in the density of nNOS-IR neurons. Significant morphological alterations were also observed in HUC/D-IR and nNOS-IR neurons; VIP-IR, CGRP-IR, and SP-IR varicosities for both groups (10 and 50 ppm F). Proteomic analysis of the duodenum demonstrated alterations in the expression of several proteins, especially those related to important biological processes, such as protein polymerization, which helps to explain the downregulation of many proteins upon exposure to 50 ppm of F.

The aim the study was to evaluate the effects of autohemotransfusion in adjuvant-induced arthritis model by injections of high and low doses of Complete Freund´s Adjuvant (CFA). Male Holtzman rats (200-230g) were distributed in six groups: control (C); control treated by autohemotransfusion (CT); CFA induced arthritis 0.5% w/v (AIA); CFA induced arthritis 0.5% w/v treated with autohemotransfusion (AIAT); CFA induced arthritis 0.1% w/v (AS) and CFA induced arthritis 0.1% w/v treated with autohemotransfusion (AST). The number of leukocytes, the weight of different organs and the paw volume were analyzed. The autohemotransfusion without erythrocytes promoted a reduction in the number of leukocytes in AIAT and AST when compared to AIA (p < 0.001). In the AST group an increase of the thymus weight (p < 0.05) was observed when compared to C, AIA and AIAT. The autohemotransfusion did not prevent the occurrence of paw edema in arthritic animals of AIAT and AST groups (p>0.05). The autohemotransfusion used in this work presented positive effects on AIA as they promoted a reduction in the number of leukocytes and an increase in thymus weight and body growth. However, other types of autohemotransfusion must be tested to determine the true efficacy of this alternative method of treatment.

The present study evaluated the effects of supplementation with a combination of vitamin C and vitamin E on NADH-diaphorase-positive (NADH-d+) and neuronal nitric oxide synthase (nNOS)-immunoreactive myenteric neurons in the duodenum and ileum in diabetic rats. Forty rats were distributed into the following groups: normoglycemic (N), normoglycemic supplemented with vitamin C and vitamin E (NS), diabetic (D), and diabetic supplemented with vitamin C and vitamin E (DS). Vitamin C was added to the drinking water, and vitamin E was incorporated in the diet (1%). After 120 days, the animals were euthanized, and the duodenum and ileum were subjected to NADH-d and nNOS staining. Quantitative and morphometric analyses of myenteric neurons were performed. Diabetes reduced NADH-d+ neurons in the D group. The density of nitrergic neurons was not changed by diabetes or vitamin treatment. Hypertrophy of the cell body area of NADH-d+ and nNOS-immunoreactive neurons was observed in both intestinal segments. Combined supplementation with vitamin C and vitamin E prevented the reduction of the density of NADH-d+ neurons and hypertrophy, demonstratred by both techniques. Supplementation with a combination of vitamin C and vitamin E promoted myenteric neuroprotection in the small intestine in diabetic rats.

We evaluated the effects of supplementation with oral l -glutamine in Walker-256 tumor–bearing rats. A total of 32 male Wistar rats aged 54 days were randomly divided into four groups: rats without Walker-256 tumor, that is, control rats (C group); control rats supplemented with l -glutamine (CG group); Walker-256 tumor rats without l -glutamine supplementation (WT group); and WT rats supplemented with l -glutamine (WTG group). l -Glutamine was incorporated into standard food at a proportion of 2 g/100 g (2%). After 10 days of the experimental period, the jejunum and duodenum were removed and processed. Protein expression levels of key enzymes of gluconeogenesis, that is, phosphoenolpyruvate carboxykinase and glucose-6-phosphatase, were analyzed by western blot and immunohistochemical techniques. In addition, plasma corticosterone, glucose, insulin, and urea levels were evaluated. The WTG group showed significantly increased plasma glucose and insulin levels ( p < 0.05); however, plasma corticosterone and urea remained unchanged. Moreover, the WTG group showed increased immunoreactive staining for jejunal phosphoenolpyruvate carboxykinase and increased expression of duodenal glucose-6-phosphatase. Furthermore, the WTG group presented with less intense cancer cachexia and slower tumor growth. These results could be attributed, at least partly, to increased intestinal gluconeogenesis and insulinemia, and better glycemia maintenance during fasting in Walker-256 tumor rats on a diet supplemented with l -glutamine.

INTRODUCTION: The mandibular condylar surface is made up of four layers, i.e., an external layer composed of dense connective tissue, followed by a layer of undifferentiated cells, hyaline cartilage and bone. Few studies have demonstrated the behavior of the condylar cartilage when the mandible is positioned posteriorly, as in treatments for correcting functional Class III malocclusion. OBJECTIVE: The aim of this study was to assess the morphologic and histological aspects of rat condyles in response to posterior positioning of the mandible. METHODS: Thirty five-week-old male Wistar rats were selected and randomly divided into two groups: A control group (C) and an experimental group (E) which received devices for inducing mandibular retrusion. The animals were euthanized at time intervals of 7, 21 and 30 days after the experiment had began. For histological analysis, total condylar thickness was measured, including the proliferative, hyaline and hypertrophic layers, as well as each layer separately, totaling 30 measurements for each parameter of each animal. RESULTS: The greatest difference in cartilage thickness was observed in 21 days, although different levels were observed in the other periods. Group E showed an increase of 39.46% in the total layer, reflected by increases in the thickness of the hypertrophic (42.24%), hyaline (46.92%) and proliferative (17.70%) layers. CONCLUSIONS: Posteriorly repositioning the mandible produced a series of histological and morphological responses in the condyle, suggesting condylar and mandibular adaptation in rats.

CONTEXT: Diabetes mellitus is a disease characterized by hyperglycemia that, when allowed to progress long-term untreated, develops vascular and neurological complications, which are responsible for the development of alterations in the enteric nervous system in diabetic patients. In the gastrointestinal tract, diabetes mellitus promotes motor and sensory changes, and in the reflex function of this system, causing gastroparesis, diarrhea, constipation, megacolon, slow gastrointestinal transit, gastric stasis and dilation with decreased or increased peristaltic contractions. Several studies have shown that oxidative stress is the main responsible for the vascular and neurological complications affecting the enteric nervous system of diabetics. OBJECTIVE: The effects of 0.1% and 2% vitamin E on myosin-V- and nNOS-immunoreactive neurons in the jejunum of diabetic rats were investigated. METHODS: Thirty rats were divided into the groups: normoglycemic, normoglycemic treated with 0.1% vitamin E, normoglycemic treated with 2% vitamin E, diabetic, diabetic treated with 0.1% vitamin E, and diabetic treated with 2% vitamin E. The neuronal density and areas of neuron cell bodies were determined. RESULTS: Diabetes (diabetic group) significantly reduced the number of myosin-V-immunoreactive neurons compared with the normoglycemic group. The diabetic treated with 0.1% vitamin E and diabetic treated with 2% vitamin E groups did not exhibit a greater density than the D group (P>0.05). Nitrergic density did not change with diabetes (P>0.05). The areas of myosin-V- and nNOS-immunoreactive neurons significantly increased in the normoglycemic treated with 2% vitamin E and diabetic groups compared with the normoglycemic group. CONCLUSION: Supplementation with 2% vitamin E had a neurotrophic effect only in the area of myosin-V-immunoreactive neurons compared with the diabetic group.CONTEXTO: O diabetes mellitus (DM) é uma doença caracterizada pela hiperglicemia que a longo prazo, quando não tratada, desenvolve complicações vasculares e neurológicas, responsáveis pelo desenvolvimento das alterações no sistema nervoso entérico de pacientes diabéticos. Em nível gastrointestinal o DM provoca modificações motoras, sensoriais e na função reflexa desse sistema, podendo ocasionar gastroparesia, diarreia, constipação, megacólon, lentidão do trânsito gastrointestinal, estase e dilatação gástrica com diminuição ou aumento de contrações peristálticas. Diversos estudos têm evidenciado que o estresse oxidativo é o principal responsável pelas complicações vasculares e neurológicas que atingem o sistema nervoso entérico de diabéticos. OBJETIVO: O efeito da vitamina E 0,1% e 2 sobre a miosina-V e nNOS imunorreativas em neurônios do jejuno de ratos diabéticos foram investigados. MÉTODOS: Trinta ratos foram divididos em grupos: normoglicêmicos (NU), normoglicêmicos tratados com vitamina E 0,1% (NE1), normoglicêmicos tratados com vitamina E 2% (NE2), diabético (UD), diabéticos tratados com vitamina E 0,1% (DE1), e diabéticos tratados com vitamina E 2% (DE2). A densidade neuronal e áreas de corpos celulares de neurônios foram determinadas. RESULTADOS: Diabetes (UD grupo) reduziu significativamente o número de neurônios miosina-V imunorreativos quando comparado com o grupo UN. Os grupos DE1 e DE2 não exibem uma maior densidade do que o grupo D (P>0,05). Densidade nitrérgicos não se alterou com diabetes (P>0,05). As áreas dos neurônios miosina-V e nNOS imunorreativos aumentaram significativamente nos grupos NE2 e UD comparados com o grupo UN. CONCLUSÃO: A suplementação com vitamina E 2% teve um efeito neurotrófico apenas na área da miosina-V imunorreativos neurônios em comparação com o grupo UD.

Aim: To compare the alveolar bone repair process using biomaterial in dogs with and without the incorporation of platelet-rich plasma. Methods: Six beagles were used. Bilateral extractions of the three mandibular premolars were performed. Bio-Gen® was applied in the first alveolus, the clot was maintained in the second alveolus and Genox® was applied to the third alveolus. PRP was added to all alveoli on the left side only. The dogs were submitted to euthanasia after 30, 60 and 90 days and submitted to histological analysis for the determination of mean area of new bone formation. Tukey’s post test was used in the statistical analysis. Results: Significant increase in bone formation occurred in Bio-Gen® + PRP when compared with the other groups at 30 and 90 days. In the evaluation at 60 days, no statistically significant differences among the groups were found. Conclusions: The Bio-Gen® biomaterial led to the best bone repair and the combination of platelet-rich plasma accelerated the repair process.

CONTEXT: The inflammatory response itself and the consequent oxidative stress are able to promote neurodegeneration. So, it is possible that enteric nervous system is affected by inflammatory diseases threatening quality of life of patients. However, gastrointestinal symptoms of arthritis are usually attributed to anti-inflammatory drugs rather than neural damage. OBJECTIVE: To confirm if the general population of myenteric neurons from the ileum and jejunum of rats is affected by arthritis. METHODS: Twenty Holtzmann rats, 58-day-old male, were used and divided in four groups: control group (C30), arthritic group (Art30), older control group (C60) and older arthritic group (Art60). At 58 days old, the animals in groups Art30 and Art60 received an injection of the complete Freund's adjuvant in order to induce arthritis. The whole-mount preparations of ileum and jejunum were processed for myosin-V immunohistochemistry. Quantitative and morphometric analyses were performed. RESULTS: Groups Art30 and Art60 presented, respectively, a reduction of 2% and 6% in intestinal area when compared to their control groups. No significant differences were observed in general neuronal density among the four groups (P>0.05). Group C60 presented a reduction of 14.4% and 10.9% in mean neuronal cell body area when compared to group C30 (P0.05). CONCLUSION: Arthritis does not promote quantitative or morphological damages in general myenteric population. However, studies in progress have revealed some significant alterations in myenteric neurons subpopulations (nitrergic and VIP-ergic neurons).

CONTEXT: Peripheral neuropathy is one of the chronic complications of diabetes mellitus and is directly related to gastrointestinal consequences of the disease. Myenteric neurons are affected in some pathological conditions such as diabetic neuropathy. The imbalance between cellular antioxidants and free radicals, leading to an increase in oxidative stress, is considered one of the main factors responsible for neuronal damages in diabetes. Drugs that reduce the oxidative stress may play a significant role in the treatment of neurological complications of diabetes mellitus. OBJECTIVE: To evaluate the effect of L-glutamine supplementation on the myenteric neurons from the cecum and duodenum of Wistar rats with streptozotocin-induced diabetes mellitus. METHODS: The animals were divided in four groups (n = 5): non-treated normoglycemics, normoglycemics treated with L-glutamine, non-treated diabetics and diabetics treated with L-glutamine from the 4th day of diabetes induction on. The amino acid L-glutamine was added to their diet at 1%. Giemsa's technique was employed to stain the myenteric neurons. We determined the cell body area of 500 neurons in each group studied. The quantitative analysis was performed by sampling in an area of 16.6 mm² in the cecum and 3.6 mm² in the duodenum of each animal. RESULTS: After the supplementation with L-glutamine in the duodenum, we observed a preservation of neuronal density in groups normoglycemic and diabetic (P

The aim of this work was to study the effect of the ascorbic acid on the myenteric neurons of diabetic rats proximal colon. Fifteen rats (90 days old) were divided into three groups: control, untreated diabetic and treated diabetic with ascorbic acid (DA). After 120 days of daily treatment with ascorbic acid, the intestinal segments were submitted to the NADH-diaphorase (NADHd) histochemistry technique to expose the myenteric neurons. The group DA showed a higher neuronal density (33.4 %) when compared to the untreated diabetic animals (p < 0.05). Cellular body area of neurons was significantly larger in group DA (17.3 %) when compared to the untreated diabetics (p < 0.05). It could be concluded that the ascorbic acid promoted a neuroprotective effect on the NADHd myenteric neurons of the proximal colon of diabetic rats.O efeito do ácido ascórbico sobre neurônios mioentéricos do colo proximal de ratos diabéticos foi avaliado. Quinze ratos com 90 dias foram divididos nos grupos: controle, diabéticos e diabéticos tratados com ácido ascórbico (DA). Após 120 dias de tratamento diário com ácido ascórbico os segmentos intestinais foram submetidos à técnica histoquímica NADH-diaforase (NADHd). A densidade neuronal, em uma área de 14,11 mm² para cada segmento, e o perfil do corpo celular de neurônios (500 neurônios/grupo) foram avaliados. O grupo DA apresentou maior densidade neuronal (33.4 %) em relação aos animais diabéticos (p < 0.05). Da mesma forma, a área do corpo celular dos neurônios foi significativamente maior no grupo DA (17.3 %) quando comparado com o grupo diabético (p < 0.05). Concluímos que o acido ascórbico apresentou um efeito neuroprotetor sobre os neurônios mioentéricos NADHd do colo proximal de ratos diabéticos.

BACKGROUND: The aging process is a deteriorating process that attacks the gastrointestinal tract, causing changes in the number and size of neurons from the enteric nervous system. The activity of free radicals on enteric neurons is helped by the significant reduction of antioxidants. AIM: Evaluate the effect of the ascorbic acid supplementation on the neurons that produce the vasoactive intestinal peptide (VIP) in the submucous plexus of the ileum of normal rats for a period of 120 days. METHODS: Fifteen rats were divided in three groups: untreated control with 90 days, untreated control with 210 days and ascorbic acid-treated rats with 210 days. Ascorbic acid was given for 16 weeks from the 90th day of age by adding it to drinking water (1 g/L prepared fresh each day). The ileums were processed according to the immunohistochemistry technique for whole-mount preparation in order to detect the presence of VIP immunoreactive in the cellular bodies and nervous fibers in the neurons of the submucous plexus. We have verified their immunoreactivity and measured the cellular profile of 80 cellular bodies of VIP-ergic neurons from each studied group. RESULTS: The ascorbic acid supplementation did not alter physiological parameters such as water intake and food consumption of the three studied groups. We observed a significant increase of the cellular profile of VIP-ergic neurons in untreated control with 210 days when compared to untreated control with 90 days. The cellular profile of VIP-ergic neurons in ascorbic acid-treated rats with 210 days was bigger than those observed in others groups. CONCLUSION: The ascorbic acid had a neurotrophic effect on VIP-ergic neurons on the ileum after period 120 days of supplementation.RACIONAL: O envelhecimento é um processo deteriorativo que acomete o trato gastrointestinal, provocando alterações no número e tamanho dos neurônios do sistema nervoso entérico. A ação dos radicais livres nos neurônios entéricos é favorecida pela diminuição significativa de antioxidantes. OBJETIVO: Avaliar o efeito da suplementação com ácido ascórbico sobre os neurônios submucosos do íleo de ratos normais que produzem o peptídio intestinal vasoativo (VIP) por um período de 120 dias. MÉTODOS: Quinze ratos foram divididos em três grupos: controles com 90 dias, controles com 210 dias e tratados com ácido ascórbico com 210 dias. O ácido ascórbico foi administrado durante 16 semanas a partir de 90 dias de idade pela adição em água (1 g/L/dia). O íleo foi processado para obtenção de preparados totais empregados na realização de técnica imunoistoquímica para detectar a presença de corpos celulares e fibras VIP imunoreativas nos neurônios do plexo submucoso. O perfil celular e a imunoreatividade de 80 corpos celulares de neurônios VIP-érgicos de cada grupo estudado foi verificada. RESULTADOS: A suplementação com ácido ascórbico não alterou parâmetros fisiológicos tais como a água ingerida e alimento consumido nos três grupos estudados. Observou-se aumento significativo do perfil celular dos neurônios VIP-érgicos dos animais controles com 210 dias, quando comparados com os controles com 90 dias. O perfil celular dos neurônios VIP-érgicos no grupo de animais tratados com ácido ascórbico foi maior do que aqueles observados nos grupos controles. CONCLUSÃO: O ácido ascórbico teve efeito neurotrófico sobre os neurônios VIP-érgicos do íleo após 120 dias de suplementação.

The effect of the treatment with acetyl-L-carnitine (ALC) on neurons releasing the vasoactive intestinal polypeptide (VIP) of the submucous plexus in the jejunum of diabetic rats was the purpose of our investigation. Diabetes (DM) was induced by injecting streptozotocin endovenously (35mg/kg). After sacrificing the animals, the jejunum was collected and processed for VIP detection. Four groups were used: C (non-diabetic), CC (non-diabetic treated with ALC), D (diabetic), DC (diabetes treated with ALC). We analyzed the immunoreactivity and the cellular profile of 126 cell bodies. The treatment with ALC improved some aspects of DM. However, it promoted a small increase in the area of neurons from group CC, suggesting a possible neurotrophic effect. Neurons from groups D and DC showed a large increase in their cellular profile and immunoreactivity when compared to C and CC, suggesting a larger concentration of this neurotransmitter within the neurons that produce it. This observation constitutes a recurrent finding in diabetic animals, suggesting that ALC doesnot interfere in the pathophysiological mechanisms that unchain a higher production and/or neurotransmitter accumulation and increase the profile of the VIP-ergic neurons.

The aim of this study was to evaluate the effect of the ascorbic acid (AA) supplementation on the neurons that produce the vasoactive intestinal peptide (VIP) in the submucous plexus of the ileum of rat, four months after the induction of experimental diabetes mellitus with streptozotocin. Three groups of rats were used: C - control, D - diabetic, DA - diabetic receiving AA. We have measured the immunoreactivity and area of 80 cellular bodies of VIP-ergic neurons from each studied group. In the diabetic animals, we have observed hyperphagia, polydipsia, and an increase of glycemia and glycated hemoglobin. The VIP-ergic neurons have presented an increase of their immunoreactivity and the highest profiles when compared to the other groups. In the diabetic animals supplemented with AA it has been observed a small reduction in the glycemia and the water and food intake. We have also noticed smaller immunoreactivity in their VIP-ergic neurons, similar to what we have observed in the control group animals (group C).

Nitric oxide (NO) mediated slow inhibitory junction potential (sIJP) and mechanical relaxation after electrical field stimulation is impaired in diabetes mellitus. Externally added NO donor restore nitrergic function, indicating that this reduction result from diminution of NO synthesis within the prejunctional nerve terminals. The present study aimed to investigate two specific aims that may potentially provide pathophysiological insights into diabetic nitrergic neuropathy. Specifically, alteration in nNOSα contents within jejunal nerve terminals and a local subcortical transporter myosin Va was tested sixteen weeks after induction of diabetes by low-dose streptozotocin in male Wistar rats. The results show that diabetic rats, in contrast to vehicle treated animals, have (a) nearly absent myosin Va expression in nerve terminals of axons innervating smooth muscles and (b) significant decrease of myosin Va in neuronal soma of myenteric plexus. In contrast, nNOSα staining in diabetic jejunum neuromuscular strips showed near intact expression in neuronal cell bodies. The space occupancy of nitrergic nerve fibers was comparable between groups. Normal concentration of nNOSα was visualized within a majority of nitrergic terminals in diabetes, suggesting intact axonal transport of nNOSα to distant nerve terminals. These results reveal the dissociation between presences of nNOSα in the nerve terminals but deficiency of its transporter myosin Va in the jejunum of diabetic rats. This significant observation of reduced motor protein myosin Va within jejunal nerve terminals may potentially explain impairment of prejunctional nitric oxide synthesis during electrical field stimulation of diabetic gut neuromuscular strips despite presence of the nitrergic synthetic enzyme nNOSα.

The purpose of this work was to study the neurons of the myenteric plexus of the cecum of rats with chronic streptozotocin-induced diabetes. We used four experimental groups of animals. In groups D2 and D8 animals were killed two and eight months, respectively, after diabetes induction and groups C2 and C8 were used as controls. We carried out whole-mount preparations stanied with Giemsa and NADH-diaphorase. We verified that the diabetes did not alter the shape and disposition of the myenteric ganglia; it provoked decrease on the neuronal density and increase on the incidence of weakly basophilic neurons. The effects of streptozotocin caused dilatation of the cecum still evidenced two months after induction, but no more observed on the eight months after induction. The smaller incidence of neurons in group D8 relative to group C8 was due to the early loss related to the drug toxicity and later to the aging in diabetic condition.O objetivo deste trabalho foi estudar os neurônios do plexo mientérico do ceco de ratos, com diabetes mellitus crônico, induzido por estreptozootocina. Utilizamos quatro grupos de animais. Nos grupos D2 e D8, os animais foram mortos, dois e oito meses, respectivamente, após à indução do diabetes e os grupos C2 e C8 foram controles dos grupos experimentais. Realizamos preparados de membrana corados pelo método de Giemsa e NADH-diaforase. Verificamos que o diabetes não alterava a forma e a disposição dos gânglios do plexo mientérico; provocou redução da densidade neuronal e aumento da freqüência de neurônios fracamente basofílicos. Os efeitos da estreptozootocina provocavam dilatação do ceco ainda evidenciada dois meses após a indução, porém não mais verificada no oitavo mês após indução. A menor freqüência de neurônios no grupo D8 em relação ao grupo C8 deve-se a perda inicial relacionada à toxicidade da droga e posteriormente ao envelhecimento em condição de diabetes.

Background: Interstitial cells of Cajal (ICC) are required for normal motility in the gastrointestinal tract. Depletion of ICC has been associated with diabetic gastroenteropathy. Aim: To determine the effect of quercertin supplementation on anoctamin-1 (Ano1) immunoreactive ICC in the myenteric region (ICC-MY) and deep muscular plexus (ICC-DMP) in the jejunum of diabetic rats. Methods: Thirty-two 90-day-old male Wistar rats were distributed into the following groups: normoglycemic (C), normoglycemic supplemented with quercetin (CQ; 40 mg daily), diabetic (D), and diabetic supplemented with quercetin (DQ; 40 mg daily). Diabetes was induced by streptozotocin injection. After 120 days, preparations of the jejunal muscular and submucosal layers were immunostained for Ano1 to visualize ICC. Evaluation of the immunofluorescence intensity as well as density of ICC was performed. Results: The density of ICC-MY was 46% lower in group D compared to group C (p < 0.01); ICC-DMP were reduced by 37% (p > 0.05). After quercertin treatment, the densities of ICC-MY were significantly higher in the DQ group compared to group D (ICC-MY: 58%, p < 0.05). Supplementation with quercetin in normoglycemic animals (CQ) compared with group C did not significantly change the ICC density (p > 0.05). Conclusions: In STZ-treated diabetic rats, diabetes promoted a reduction in the density of jejunal ICC-MY with no significant effect on ICC-DMP. Supplementation with quercetin (DQ) appeared to protect ICC-MY from depletion in diabetes possibly due to its antioxidant action.

ABSTRACT BACKGROUND: Few studies regarding arthritic diseases have been performed to verify the presence of the neurodegeneration. Given the increased oxidative stress and extra-articular effects of the rheumatoid arthritis, the gastrointestinal studies should be further investigated aiming a better understanding of the systemic effects the disease on enteric nervous system. OBJECTIVE: To determine whether the rheumatoid arthritis affects the nitrergic density and somatic area of the nNOS- immunoreactive (IR) myenteric neurons, as well as the morphometric areas of CGRP and VIP-IR varicosities of the ileum of arthritic rats. METHODS: Twenty 58-day-old male Holtzmann rats were distributed in two groups: control and arthritic. The arthritic group received a single injection of the Freund’s Complete Adjuvant in order to induce arthritis model. The whole-mount preparations of ileum were processed for immunohistochemistry to VIP, CGRP and nNOS. Quantification was used for the nitrergic neurons and morphometric analyses were performed for the three markers. RESULTS: The arthritic disease induced a reduction 6% in ileal area compared to control group. No significant differences were observed in nitrergic density comparing both groups. However, arthritic group yielded a reduction of the nitrergic neuronal somatic area and VIP-IR varicosity areas. However, an increase of varicosity CGRP-IR areas was also observed. CONCLUSION: Despite arthritis resulted in no alterations in the number of nitrergic neurons, the retraction of ileal area and reduction of nitrergic somatic and VIP-IR varicosity areas may suggest a negative impact the disease on the ENS.