RESUMO
AIMS: Our main goals were to investigate the effects of L-glutathione (1%) treatment in Walker-256 tumor-bearing rats by analyzing immunoreactive neurons (IR), responsive to the nNOS enzyme and 3-Nitrotyrosine, in their jejunum myenteric plexus. Moreover, the oxidative state and inflammatory process in these animals were investigated. METHODS: Four experimental groups were utilized: control (C), control treated with L-glutathione (CGT), Walker-256 tumor-bearing rats (TW), and Walker-256 tumor-bearing rats treated with L-glutathione (TWGT). After 14 days of tumor inoculation, the jejunum was collected for immunohistochemical techniques and assessment of oxidative status. Plasma was collected to evaluate oxidative status and measure cytokines. RESULTS: The TW group exhibited a decrease of reduced glutathione in their jejunum, which was prevented in the L-glutathione treated TWGT group. TW animals presented pronounced oxidative stress by increasing levels of lipoperoxidation in their jejunum and malondialdehyde in their plasma; however, the L-glutathione treatment in TWGT group was not able to avoid it. The total antioxidant capacity was altered in groups TW and TWGT, yet the last one had a better index in their plasma. The IL-10, and TNF-α levels increased in TWGT animals. The nNOS-IR neuron density decreased in the jejunum myenteric plexus of the TW group, which was avoided in the TWGT group. The nNOS +3-Nitrotyrosine neurons quantification did not show significative alterations. CONCLUSION: The treatment with L-glutathione (1%) imposed an important defense to some parameters of oxidative stress induced by TW-256, leading to neuroprotection to the loss in the nNOS-IR neuron density.
Assuntos
Neoplasias , Neurônios Nitrérgicos , Ratos , Animais , Jejuno , Ratos Wistar , Neuroproteção , Estresse Oxidativo , Glutationa/metabolismo , Plexo Mientérico/patologia , Neoplasias/metabolismo , Neoplasias/patologiaRESUMO
Considering the antioxidant, neuroprotective, inflammatory and nitric oxide modulatory actions of quercetin, the aim of this study was to test the effect of quercetin administration in drinking water (40 mg/day/rat) on neuronal nitric oxide synthase (nNOS), vasoactive intestinal peptide (VIP), overall population of myenteric neurons (HuC/D) and nitric oxide (NO) levels in the jejunal samples from diabetic rats. Male Wistar rats were distributed into four groups (8 rats per group): euglycemic (E), euglycemic administered with quercetin (E+Q), diabetic (D) and diabetic administered with quercetin (D+Q). Rats were induced to diabetes with streptozotocin (35mg/kg/iv) and, after 120 days, the proximal jejunum were collected and processed for immunohistochemical (VIP, nNOS and HuC/D) and chemiluminescence (quantification of tissue NO levels) techniques. Diabetes mellitus reduced the number of nNOS-IR (immunoreactive) (p <0.05) and HuC/D-IR (p <0.001) neurons, however, promoted an increased morphometric area of nNOS-IR neurons (p <0.001) and VIP-IR varicosities (p <0.05). In D+Q group, neuroplasticity effects were observed on HuC/D-IR neurons, accompanied by a reduction of cell body area of neurons nNOS- and VIP-IR varicosities (p <0.05). The NO levels were increased in the E+Q (p <0.05) and D+Q group (p <0.001) compared to the control group. In conclusion, the results showed that quercetin supplementation increased the bioavailability of NO in the jejunum in euglycemic and mitigate the effects of diabetes on nNOS-IR neurons and VIP-IR varicosities in the myenteric plexus of diabetic rats.
Assuntos
Antioxidantes/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Jejuno/efeitos dos fármacos , Plexo Mientérico/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Óxido Nítrico Sintase Tipo I/efeitos dos fármacos , Óxido Nítrico/metabolismo , Quercetina/farmacologia , Peptídeo Intestinal Vasoativo/efeitos dos fármacos , Animais , Antioxidantes/administração & dosagem , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Masculino , Plexo Mientérico/patologia , Quercetina/administração & dosagem , Ratos , Ratos WistarRESUMO
BACKGROUND: Obesity has been linked to gastrointestinal disorders, and the loss of myenteric neurons in the intestine caused by high-fat diets (HFD) has been attributed to changes in microbiota and lipotoxicity. We investigated whether the prebiotic inulin modulates bacterial populations and alleviates neuronal loss in mice fed HFD. METHODS: Swiss mice were fed purified rodent diet or HFD (59% kcal fat), or both diets supplemented with inulin for 17 weeks. Intestinal motility was assessed and a metagenome analysis of the colonic microbiota was performed. The gene expression of inflammatory markers was evaluated, and immunofluorescence was performed for different types of myenteric neurons and glial cells in the distal colon. KEY RESULTS: The HFD caused obesity and delayed colonic motility. The loss of myenteric neurons and glial cells in obese mice affected all of the studied neuronal populations, including neurons positive for myosin-V, neuronal nitric oxide synthase, vasoactive intestinal peptide, and calretinin. Although obese mice supplemented with inulin exhibited improvements in colonic motility, neuronal, and glial cell loss persisted. The HFD did not altered the expression levels of inflammatory cytokines in the intestine or the prevalence of the major groups in microbiota, but inulin increased the proportion of the genus Akkermansia in the obese mice. CONCLUSIONS AND INFERENCES: In Swiss mice, the HFD-induced neuronal loss but did not change the major groups in microbiota. This suggests that, despite the increase in the beneficial bacteria, other factors that are directly linked to excess dietary lipid intake affect the enteric nervous system.
Assuntos
Dieta Hiperlipídica/efeitos adversos , Microbioma Gastrointestinal , Plexo Mientérico/patologia , Neurônios/patologia , Obesidade/patologia , Animais , Motilidade Gastrointestinal/fisiologia , Inulina/farmacologia , Masculino , Camundongos , Obesidade/etiologia , Probióticos/farmacologiaRESUMO
INTRODUCTION: Our work analyzed the effects of a P2X7 receptor antagonist, Brilliant Blue G (BBG), on rat ileum myenteric plexus following ischemia and reperfusion (ISR) induced by 45 min of ileal artery occlusion with an atraumatic vascular clamp with 24 h (ISR 24-h group) or 14 d of reperfusion (ISR 14-d group). MATERIAL AND METHODS: Either BBG (50 mg/kg or 100 mg/kg, BBG50 or BBG100 groups) or saline (vehicle) was administered subcutaneously 1 h after ischemia in the ISR 24-h group or once daily for the 5 d after ischemia in the ISR 14-d group (n = 5 per group). We evaluated the neuronal density and profile area by examining the number of neutrophils in the intestinal layers, protein expression levels of the P2X7 receptor, intestinal motility and immunoreactivity for the P2X7 receptor, nitric oxide synthase, neurofilament-200, and choline acetyl transferase in myenteric neurons. RESULTS: The neuronal density and profile area were restored by BBG following ISR. The ischemic groups showed alterations in P2X7 receptor protein expression and the number of neutrophils in the intestine and decreased intestinal motility, all of which were recovered by BBG treatment. CONCLUSION: We concluded that ISR morphologically and functionally affected the intestine and that its effects were reversed by BBG treatment, suggesting the P2X7 receptor as a therapeutic target.
Assuntos
Íleo/inervação , Isquemia Mesentérica/tratamento farmacológico , Plexo Mientérico/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Antagonistas do Receptor Purinérgico P2X/farmacologia , Receptores Purinérgicos P2X7/efeitos dos fármacos , Traumatismo por Reperfusão/prevenção & controle , Corantes de Rosanilina/farmacologia , Animais , Citoproteção , Modelos Animais de Doenças , Motilidade Gastrointestinal/efeitos dos fármacos , Masculino , Isquemia Mesentérica/metabolismo , Isquemia Mesentérica/patologia , Isquemia Mesentérica/fisiopatologia , Plexo Mientérico/metabolismo , Plexo Mientérico/patologia , Neurônios/metabolismo , Neurônios/patologia , Infiltração de Neutrófilos/efeitos dos fármacos , Ratos Wistar , Receptores Purinérgicos P2X7/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Transdução de Sinais/efeitos dos fármacosRESUMO
BACKGROUND: Toxoplasma gondii infection can occur through the ingestion of raw meat that contains tissue cysts or food that contains oocysts. Through the ingestion of oocysts, the parasite crosses the intestinal barrier, where the enteric nervous system is located. The objective was to investigate the kinetics of neuronal and glial responses during acute T. gondii infection. METHODS: We used 45 Wistar rats that were divided into a control group and infected groups that were evaluated at 6, 12, 24, 48, 72 hours, 7 days, 10 days, and 15 days after infection. The rats received 5000 sporulated oocysts of the parasite orally. To detect neurons and enteric glia cells, the myenteric and submucosal plexuses of the duodenum underwent double-labeling immunohistochemical techniques to evaluate HuC/HuD and S100, HuC/HuD and ChAT, and HuC/HuD and nNOS. KEY RESULTS: We observed a reduction of the total neuron population in the submucosal plexus 72 hours after infection. Cholinergic neurons decreased in the submucosal plexus 15 days after infection, and nitrergic neurons decreased in the myenteric plexus 72 hours after infection. A decrease in the number of glial cells was observed 7 days after infection in the submucosal plexus, and an increase in the enteric glial cell (EGC)/neuron ratio was found in both plexuses 48 hours after infection. CONCLUSIONS AND INFERENCES: We found decrease of neurons and increase in the EGC/neuron ratio in both plexuses caused by acute T. gondii infection, with major alterations 72 hours after oral infection. The number of cholinergic neurons decreased in the submucosal plexus, and the number of nitrergic neurons decreased in the myenteric plexus. A decrease in the number of enteric glial cells was observed in the submucosal plexus, and an increase in the enteric glial cell/neuron ratio was observed in both ganglionate plexuses of the duodenum.
Assuntos
Duodeno/patologia , Neuroglia/patologia , Neurônios/patologia , Toxoplasmose/patologia , Doença Aguda , Animais , Contagem de Células , Imuno-Histoquímica , Plexo Mientérico/patologia , Sistema Nervoso Parassimpático/patologia , Ratos , Ratos Wistar , Plexo Submucoso/patologiaRESUMO
Duchenne-like muscular dystrophy (canine dystrophinopathy) is a hereditary degenerative disease characterized by muscle changes similar to those described for Duchenne muscular dystrophy (DMD) and by alterations in the smooth muscles of the gastrointestinal tract. Some authors have suggested that these abnormalities may be associated with intestinal motility. This study analyzed the nitrergic and cholinergic neurons and P2X7 receptor expression in the myenteric plexus of the ileum and distal colon of dogs with muscular dystrophy. Immunohistochemical techniques were used to detect nitric oxide synthase (NOS) and acetylcholine transferase (ChAT) expression and to label all HuC/D- and P2X7 receptor-immunoreactive (IR) neurons. Transmission electron microscopy and basic histology were performed for further analysis. The results showed that nitrergic neurons exhibited a Dogiel type I morphology in the ileum and distal colon. The neuronal profile results showed that there were fewer NOS-, ChAT-, and HuC/D-IR neurons in the ileum than in the distal colon in the dystrophic (DT) dogs. Additionally, there were more NOS-, ChAT- and HuC/D-IR neurons per ganglion in the distal colon than in the ileum. The P2X7 receptor-expressing neurons colocalized with nitrergic and cholinergic neurons. Transmission and light microscopy revealed collagen between the muscle fibers, between the circular and longitudinal muscle layers and within the myenteric ganglia of dogs with muscular dystrophy. These findings provide a morphological description of the myenteric neurons in the ileum and distal colon of these DT dogs and may contribute to a better understanding of the gastrointestinal disorders found in patients with DMD. Anat Rec, 301:673-685, 2018. © 2017 Wiley Periodicals, Inc.
Assuntos
Colo/patologia , Doenças do Cão/patologia , Íleo/patologia , Distrofia Muscular Animal/patologia , Plexo Mientérico/patologia , Animais , Colina O-Acetiltransferase/metabolismo , Colo/metabolismo , Doenças do Cão/metabolismo , Cães , Íleo/metabolismo , Distrofia Muscular Animal/metabolismo , Plexo Mientérico/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Óxido Nítrico Sintase/metabolismo , Receptores Purinérgicos P2X7/metabolismoRESUMO
BACKGROUND: The intestinal mucosa plays an important role in the mechanical barrier against pathogens. During Toxoplasma gondii infection, however, the parasites invade the epithelial cells of the small intestine and initiate a local immune response. In the submucosal plexus, this response promotes an imbalance of neurotransmitters and induces neuroplasticity, which can change the integrity of the epithelium and its secretory function. This study evaluated the submucosal neurons throughout acute T. gondii infection and the relationship between possible alterations and the epithelial and immune defense cells of the mucosa. METHODS: Forty Wistar rats were randomly assigned to 8 groups (n = 5): 1 control group, uninfected, and 7 groups infected with an inoculation of 5000 sporulated T. gondii oocysts (ME-49 strain, genotype II). Segments of the ileum were collected for standard histological processing, histochemical techniques, and immunofluorescence. KEY RESULTS: The infection caused progressive neuronal loss in the submucosal general population and changed the proportion of VIPergic neurons throughout the infection periods. These changes may be related to the observed reduction in goblet cells that secret sialomucins and increase in intraepithelial lymphocytes after 24 hours, and the increase in immune cells in the lamina propria after 10 days of infection. The submucosa also presented fibrogenesis, characterizing injury and tissue repair. CONCLUSIONS AND INFERENCES: The acute T. gondii infection in the ileum of rats changes the proportion of VIPergic neurons and the epithelial cells, which can compromise the mucosal defense during infection.
Assuntos
Células Caliciformes/metabolismo , Íleo/metabolismo , Linfócitos Intraepiteliais/metabolismo , Neurônios/metabolismo , Toxoplasmose/metabolismo , Peptídeo Intestinal Vasoativo/metabolismo , Animais , Contagem de Células , Morte Celular/fisiologia , Células Caliciformes/microbiologia , Células Caliciformes/patologia , Íleo/microbiologia , Íleo/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Linfócitos Intraepiteliais/microbiologia , Linfócitos Intraepiteliais/patologia , Masculino , Plexo Mientérico/metabolismo , Plexo Mientérico/microbiologia , Plexo Mientérico/patologia , Neurônios/microbiologia , Neurônios/patologia , Ratos , Ratos Wistar , Toxoplasma , Toxoplasmose/microbiologia , Toxoplasmose/patologiaRESUMO
AIM: To evaluate the mucosal tunic and submucosal plexus of the jejunum of rats infected with different inoculum doses of Toxoplasma gondii. MAIN METHODS: Rats were infected with different inoculum doses (50, 500, 1000 and 5000 oocysts) of the T. gondii for 30days, while a control group (CG) received saline solution. Blood and feces were collected before euthanasia for analysis of blood and fecal leukocytes (LEs). Histological analysis of the mucosa, submucosa, villi, crypts and enterocytes were performed. Goblet cells, intraepithelial lymphocytes (IELs) and Paneth cells were quantified. Immunohistochemistry was used to assess enteroendocrine serotonergic (5HT-IR) cells, proliferative cells (PCNA+) and mast cells. Whole mounts were obtained to determine the total submucosal neurons by Giemsa staining and metabolically active neurons (NADH-d+), nitrergic neurons (NADPH-d+) and glial cells (S100). KEY FINDINGS: An increase in blood LEs was observed 30days post-infection (dpi). Fecal LEs were more abundant in the feces in all infected groups at 21 dpi when compared to the CG. The number of IELs, sulfomucin-producing goblet cells, Paneth cells, PCNA+ cells and mast cells increased, whereas the number of 5HT-IR cells decreased. The jejunal architecture was altered, with atrophy of the mucosa, submucosa, villi and crypts. The number of total submucosal neurons decreased, but the NADPH-d+ subpopulation increased. SIGNIFICANCE: The results show how chronic toxoplasmic infection affects the tissue and cellular composition of the rat jejunum. These structural changes tend to intensify with the inoculum dose, demonstrating the importance of the parasitic load on intestinal alterations.
Assuntos
Jejuno/patologia , Toxoplasma/fisiologia , Toxoplasmose/patologia , Animais , Enterócitos/parasitologia , Enterócitos/patologia , Fezes/parasitologia , Mucosa Intestinal/parasitologia , Mucosa Intestinal/patologia , Jejuno/parasitologia , Contagem de Leucócitos , Masculino , Plexo Mientérico/parasitologia , Plexo Mientérico/patologia , Neurônios/parasitologia , Neurônios/patologia , Ratos , Ratos Wistar , Toxoplasmose/sangue , Toxoplasmose/parasitologiaRESUMO
In the enteric nervous system (ENS), nitrergic neurons produce and use nitric oxide (NO) as an inhibitory motor neurotransmitter in response to parasitic infections, including those caused by Toxoplasma gondii. However, damage to the host caused by NO has been reported by various authors, and the role of NO in protection or cytotoxicity continues to be extensively studied. In this study, nitrergic neurons were investigated in the myenteric plexus of the jejunum and the distal colon of rats infected with 500 oocysts of the M7741 strain of T. gondii. Ten rats were randomly assigned into a control group (CG) and infected group (IG; received 500 sporulated oocysts of T. gondii orally). After 24h, the rats were euthanized, and samples of the jejunum and distal colon were obtained and processed for NADPH-diaphorase histochemical analysis. Quantitative and morphometric analysis of the nitrergic neurons in whole mounts containing the myenteric plexus was performed. There was a numeric reduction of nitrergic neurons per mm2 in both jejunum and distal colon. The remaining nitrergic neurons suffered atrophy in the areas of the cell body and nucleus, which resulted in a decrease in cytoplasm. Thus, we conclude that an avirulent strain of T. gondii in a short time causes neuroplastic changes in the small and large intestine of rats.
Assuntos
Neurônios Nitrérgicos/parasitologia , Toxoplasma/patogenicidade , Toxoplasmose/patologia , Animais , Intestinos/inervação , Intestinos/parasitologia , Plexo Mientérico/parasitologia , Plexo Mientérico/patologia , Neurônios Nitrérgicos/patologia , Distribuição Aleatória , Ratos , Ratos Wistar , Toxoplasma/fisiologia , VirulênciaRESUMO
BACKGROUND: Experimental and clinical studies have shown that myenteric neuron cell death during infection with Trypanosoma cruzi mainly occurs in the esophagus and colon, resulting in megaesophagus and megacolon, respectively. Evidence suggests that the cyclooxygenase enzyme (COX) is involved in the T. cruzi invasion process. The use of low-dose aspirin (ASA), a COX-1/COX-2 inhibitor, has been shown to reduce infection with T. cruzi. Therefore, in this study, we evaluated the effects of treatment with low-dose ASA on myenteric colonic neurons during murine infection with T. cruzi. METHODS: Swiss mice were assigned into groups treated with either phosphate-buffered saline or low doses of ASA during the acute phase (20 mg/kg ASA) and chronic phase (50 mg/kg ASA) of infection with the Y strain of T. cruzi. Seventy-five days after infection, colon samples were collected to quantify inflammatory foci in histological sections and also general (myosin-V+ ), nitrergic, and VIPergic myenteric neurons in whole mounts. Gastrointestinal transit time was also measured. KEY RESULTS: Aspirin treatment during the acute phase of infection reduced parasitemia (P<.05). Aspirin treatment during the acute or chronic phase of the infection reduced the intensity of inflammatory foci in the colon, protected myenteric neurons from cell death and plastic changes, and recovered the gastrointestinal transit of mice infected with T. cruzi (P<.05). CONCLUSION & INFERENCES: Early and delayed treatment with low-dose ASA can reduce the morphofunctional damage of colonic myenteric neurons caused by murine T. cruzi infection.
Assuntos
Aspirina/farmacologia , Doença de Chagas/patologia , Inibidores de Ciclo-Oxigenase/farmacologia , Plexo Mientérico/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Plexo Mientérico/patologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Trypanosoma cruziRESUMO
The Duchenne Muscular Dystrophy (DMD) is a genetic disorder characterized by the absence of dystrophin protein, causing severe myopathy from increases of oxidative stress. Injuries of intestinal muscle can compromise the myenteric plexus. This study aimed to evaluate the disorders occurred in the muscular layer and in the acetylcholinesterase myenteric neurons (ACHE-r) of ileum of mdx mice, and the effects of supplementation with ascorbic acid (AA) in both components. 30 male mice C57BL/10, and 30 male mice C57BL/10Mdx were separated according to the age and treatment (n=10/group): 30-days-old control group (C30); 30-days-old dystrophic group (D30); 60-days-old control group (C60); 60-days-old dystrophic group (D60); 60-days-old control group supplemented with AA (CS60); and 60-days-old dystrophic group supplemented with AA (DS60). The animals were euthanized and the ileum was collected and processed. Semi-serial sections were stained by Masson's trichrome, and acetylcholinesterase histochemical technique in whole-mounts preparations to identify the myenteric neurons. The muscular layer thickness and the area of smooth muscle of ileum were lower in dystrophic groups, especially in D30 group. The DS60 group showed the muscular layer thickness similar to C60. The density of ACHE-r neurons of myenteric plexus of ileum was lower in D30 animals; however, it was similar in animals of 60-days-old without treatment (C60 and D60) and, higher in DS60. The cell body profile area of ACHE-r neurons was similar in C30-D30 and C60-D60; however, it was higher in DS60. DMD caused damage to the ileum's musculature and myenteric plexus, and the AA prevented the ACHE-r neuronal loss.
Assuntos
Acetilcolinesterase/metabolismo , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Íleo/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Animais , Contagem de Células , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Núcleo Celular/patologia , Tamanho Celular/efeitos dos fármacos , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Citoplasma/patologia , Modelos Animais de Doenças , Íleo/enzimologia , Íleo/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Músculo Liso/metabolismo , Músculo Liso/patologia , Distrofia Muscular de Duchenne/tratamento farmacológico , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/patologia , Plexo Mientérico/efeitos dos fármacos , Plexo Mientérico/enzimologia , Plexo Mientérico/patologia , Neurônios/enzimologia , Neurônios/patologia , Tamanho do ÓrgãoRESUMO
The consequences of using aspirin (ASA) for the pathogenesis of Chagas disease are unclear. This study evaluated the effects of treatment of Chagas disease with ASA on the esophageal nitrergic myenteric neuron population and esophageal wall in mice. We observed that treatment of chagasic infection with ASA protects the esophageal myenteric neurons from the atrophy caused by the Trypanosoma cruzi infection. The mice were infected with 1300 trypomastigotes of Y strain T. cruzi intraperitoneally. Part of infected mice was treated with ASA from fifth to twelfth day after inoculation. Our data support the hypothesis that eicosanoids given during the acute phase of the chagasic infection may act as immunomodulators aiding the transition to and maintenance of the chronic phase of the disease. Besides, ASA treatment did not provoke alterations in the esophageal wall and the myenteric neurons in infected mice.
Assuntos
Aspirina/farmacologia , Doença de Chagas/tratamento farmacológico , Inibidores de Ciclo-Oxigenase/farmacologia , Esôfago/inervação , Plexo Mientérico/efeitos dos fármacos , Neurônios Nitrérgicos/efeitos dos fármacos , Animais , Atrofia/prevenção & controle , Doença de Chagas/parasitologia , Doença Crônica , Modelos Animais de Doenças , Masculino , Camundongos , Plexo Mientérico/patologia , Neurônios Nitrérgicos/patologia , Resultado do Tratamento , Trypanosoma cruzi/efeitos dos fármacosRESUMO
Patients with Chagas' disease may develop dysfunctions of oesophageal and colonic motility resulting from the degeneration or loss of the myenteric neurons of the enteric nervous system. Studies have shown that the use of aspirin, also known as acetylsalicylic acid (ASA), influences the pathogenesis of the disease. However, this remains controversial. The aim of this study was to evaluate the consequences of treatment with low doses of aspirin during the chronic phase of Chagas' disease on oesophageal function. Twenty male Swiss mice, 60 days of age, were used. The animals were infected with Y strain of Trypanosoma cruzi, injected intraperitoneally. Aspirin was given at a dose of 50 mg/kg to some of the infected animals, from the 55th to 63rd day after inoculation on consecutive days, and from the 65th to 75th day on alternate days. We investigated food passage of time, wall structure and nitrergic neuronal population of the distal oesophagus. Our data revealed that the use of low doses of aspirin in chronic Chagas' disease caused an increase in the number of nitrergic neurons and partially prevented hypertrophy of the oesophagus. In addition, the aspirin administration impeded Chagas' diseases associated changes in intestinal transit time. Thus treatment with aspirin in the chronic phase of Chagas' disease changes the natural history of the disease and raises the possibility of using it as a new therapeutic approach to the treatment of this aspect of Chagas' disease pathology.
Assuntos
Aspirina/farmacologia , Doença de Chagas/tratamento farmacológico , Esôfago/patologia , Neurônios/efeitos dos fármacos , Animais , Aspirina/administração & dosagem , Doença de Chagas/patologia , Doença Crônica , Colo/patologia , Modelos Animais de Doenças , Esôfago/efeitos dos fármacos , Masculino , Camundongos , Plexo Mientérico/efeitos dos fármacos , Plexo Mientérico/patologia , Neurônios/patologiaRESUMO
AIMS: The present study evaluated the effects of resveratrol in the myenteric plexus after intestinal ischemia-reperfusion (I/R) injury caused by occluding the superior mesenteric artery for 45min, followed by 7days of reperfusion. MAIN METHODS: Forty-two male Wistar rats were divided into seven groups: control (C group), untreated sham surgery control (SC group), sham surgery control treated with resveratrol before surgery (STA group), sham surgery control treated with resveratrol before and after surgery (STAD group), ischemic control (IRC group), ischemic treated before I/R (IRTA group), and ischemic treated before and after I/R (IRTAD group). Resveratrol (10mg/kg) was administered for 4days and 2h prior to surgery and/or 7days later. Morphometric analyses were performed, and the density of the general neuronal population (HuC/D-immunoreactive [IR]), nitrergic subpopulation (neuronal nitric oxide synthase [nNOS]-IR), vasoactive intestinal peptide (VIP)ergic varicosities (VIP-IR), and glial cells (S100-IR) was determined. KEY FINDINGS: Injury that was caused by I/R significantly reduced (p<0.01) the HuC/D-IR general neuronal population. Treatment with resveratrol before and after ischemia had a neuroprotective effect. Morphometric changes caused by I/R in nitrergic neurons and varicosities were also attenuated by resveratrol. Ischemia/reperfusion promoted the proliferation of enteric glial cells, and resveratrol treatment before and after I/R reversed this effect. SIGNIFICANCE: Resveratrol had neuroprotective effects, showing promise for application in intestinal surgery and transplants.
Assuntos
Antioxidantes/uso terapêutico , Íleo/inervação , Plexo Mientérico/efeitos dos fármacos , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Estilbenos/uso terapêutico , Animais , Proliferação de Células/efeitos dos fármacos , Íleo/efeitos dos fármacos , Íleo/patologia , Masculino , Plexo Mientérico/citologia , Plexo Mientérico/patologia , Neuroglia/citologia , Neuroglia/efeitos dos fármacos , Neuroglia/patologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Óxido Nítrico Sintase Tipo I/análise , Ratos , Ratos Wistar , Traumatismo por Reperfusão/patologia , ResveratrolRESUMO
BACKGROUND: Intestinal ischemia/reperfusion injury can be caused by surgical procedures and inflammatory bowel disease. It is normally associated with the increased production of free radicals and changes in the enteric nervous system. AIMS: Given the antioxidant and neuroprotective properties of resveratrol, the present study assessed its influence on oxidative stress in the intestinal wall and the morphology of myenteric neurons in the ileum of rats subjected to ischemia/reperfusion. METHODS: Resveratrol was orally administered daily at a dose of 10 mg/kg for 5 days. Changes in the ileum response to ischemia after 45 min were investigated followed by 3 h reperfusion. Lipoperoxide and carbonylated protein levels, and the activity of the antioxidant enzymes glutathione reductase, glutathione peroxidase, and glucose-6-phosphate dehydrogenase were measured following ischemia/reperfusion injury. RESULTS: The density and morphometry of the general neuronal population, nitrergic neurons and glial cells, and morphometry of VIP varicosities in the ileum were also studied. Lipoperoxide and carbonylated protein levels were 171 and 40% higher during the ischemia/reperfusion, respectively, compared to control cohorts, and resveratrol attenuated these values. The glutathione ratio was 64% lower during ischemia/reperfusion, compared to control cohorts. Resveratrol increased the reduced/oxidized glutathione ratio, attenuated the changes in the activity of the antioxidant enzymes and the detrimental morphologic changes caused by ischemia/reperfusion in the general neuronal population and nitrergic neurons. CONCLUSIONS: Oral treatment with resveratrol reduced the oxidative stress in the ileum and attenuated the morphologic changes that occurred in the myenteric plexus of the ileum in rats subjected to ischemia/reperfusion.
Assuntos
Antioxidantes/farmacologia , Doenças do Íleo/tratamento farmacológico , Íleo/efeitos dos fármacos , Plexo Mientérico/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico , Estilbenos/farmacologia , Administração Oral , Animais , Antioxidantes/administração & dosagem , Modelos Animais de Doenças , Glucosefosfato Desidrogenase/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Doenças do Íleo/metabolismo , Doenças do Íleo/patologia , Íleo/inervação , Íleo/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Plexo Mientérico/metabolismo , Plexo Mientérico/patologia , Fármacos Neuroprotetores/administração & dosagem , Neurônios Nitrérgicos/efeitos dos fármacos , Neurônios Nitrérgicos/metabolismo , Neurônios Nitrérgicos/patologia , Carbonilação Proteica/efeitos dos fármacos , Ratos Wistar , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Resveratrol , Estilbenos/administração & dosagemRESUMO
Idiopathic achalasia is a disease of unknown etiology. The loss of myenteric plexus associated with inflammatory infiltrates and autoantibodies support the hypothesis of an autoimmune mechanism. Thirty-two patients diagnosed by high-resolution manometry with achalasia were included. Twenty-six specimens from lower esophageal sphincter muscle were compared with 5 esophagectomy biopsies (control). Immunohistochemical (biopsies) and flow cytometry (peripheral blood) analyses were performed. Circulating anti-myenteric autoantibodies were evaluated by indirect immunofluorescence. Herpes simplex virus-1 (HSV-1) infection was determined by in situ hybridization, RT-PCR, and immunohistochemistry. Histopathological analysis showed capillaritis (51%), plexitis (23%), nerve hypertrophy (16%), venulitis (7%), and fibrosis (3%). Achalasia tissue exhibited an increase in the expression of proteins involved in extracellular matrix turnover, apoptosis, proinflammatory and profibrogenic cytokines, and Tregs and Bregs versus controls (P < 0.001). Circulating Th22/Th17/Th2/Th1 percentage showed a significant increase versus healthy donors (P < 0.01). Type III achalasia patients exhibited the highest inflammatory response versus types I and II. Prevalence of both anti-myenteric antibodies and HSV-1 infection in achalasia patients was 100% versus 0% in controls. Our results suggest that achalasia is a disease with an important local and systemic inflammatory autoimmune component, associated with the presence of specific anti-myenteric autoantibodies, as well as HSV-1 infection.
Assuntos
Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Acalasia Esofágica/imunologia , Acalasia Esofágica/patologia , Inflamação/imunologia , Inflamação/patologia , Adulto , Idoso , Autoanticorpos/imunologia , Doenças Autoimunes/virologia , Estudos de Casos e Controles , Estudos Transversais , Acalasia Esofágica/virologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo/métodos , Herpes Simples/imunologia , Herpesvirus Humano 1/imunologia , Humanos , Imuno-Histoquímica/métodos , Inflamação/virologia , Masculino , Pessoa de Meia-Idade , Plexo Mientérico/imunologia , Plexo Mientérico/patologia , Plexo Mientérico/virologiaRESUMO
Toxoplasmosis is a widely distributed disease caused by the protozoan Toxoplasma gondii that is mainly transmitted orally. Once ingested, the parasite crosses the intestinal barrier to reach the blood and lymph systems to migrate to other regions of the host. The objective of this study was to evaluate the changes in the myenteric plexus and the jejunal wall of Wistar rats caused by oral infection with T. gondii oocysts (ME-49 strain). Inocula of 10, 100, 500 and 5000 oocysts were used. The total population of myenteric neurons and the most metabolically active subpopulation (NADH-diaphorase positive - NADH-dp) exhibited a decrease proportional to the dose of T. gondii. There was also a quantitative increase in the subpopulation of NADPH-diaphorase-positive (NADPH-dp) myenteric neurons, indicating greater expression of the NOS enzyme. Neuronal atrophy was observed, and morphological and morphometric alterations such as jejunal atrophy were found in the infected groups. Hypertrophy of the external muscle with the presence of inflammatory foci was observed in the group infected with 5000 oocysts. The changes observed in the infected groups were proportional to the number of oocysts inoculated.
Assuntos
Jejuno/patologia , Plexo Mientérico/patologia , Toxoplasmose Animal/patologia , Animais , Anticorpos Antiprotozoários/sangue , Modelos Animais de Doenças , Histocitoquímica , Imunoglobulina G/sangue , Masculino , NAD , NADP , Neurônios/patologia , Distribuição Aleatória , Ratos , Ratos Wistar , Toxoplasma/imunologiaRESUMO
BACKGROUND: We investigated the effects of ischemia followed by different periods of reperfusion (I/R) on immunoreactive S100ß-positive glial and Hu-immunoreactive neurons co-expressing the P2X2 receptor in the myenteric plexus of the rat ileum. METHODS: The ileal artery was occluded for 35 min with an atraumatic vascular clamp. The animals were killed 24 h, 72 h, and 1 week after ischemia. Sham animals were not submitted to ileal artery occlusion. The relative density, size, and co-localization of P2X2 receptor-expressing cells in relation to S100ß-immunoreactive glial and Hu-immunoreactive neuronal cells were evaluated. Additionally, we analyzed the effects of I/R on gastrointestinal transit and ileum contractile activity. RESULTS: The cellular density of P2X2 receptor and neuronal Hu immunoreactivity/cm(2) decreased after I/R, whereas glial S100ß immunoreactivity/cm(2) increased. No significant differences between sham and I/R groups were observed regarding the perikarya area of Hu-positive neurons. The area of S100ß-immunoreactive glial cells increased by 24.1 % 1 week after I/R compared with the 24 h group. Methylene blue progression along the small intestine decreased (P < 0.05) from 24.5 ± 2.3 % in the sham group to 17.2 ± 2.0 % 1 week post-ischemia. We noted a significant (P < 0.05) decrease in the maximal contraction amplitude triggered by electrical field stimulation in the presence of ATP in preparations submitted to 24 h of I/R. CONCLUSIONS: Changes in the P2X2 receptor density parallel myenteric neuronal loss following I/R of the rat ileum. This, together with the increase in the activated (oversized) glial cells, may contribute to decreased GI motility after I/R.
Assuntos
Íleo/irrigação sanguínea , Músculo Liso/fisiopatologia , Plexo Mientérico/metabolismo , Neuroglia/metabolismo , Receptores Purinérgicos P2X2/metabolismo , Traumatismo por Reperfusão/fisiopatologia , Animais , Trânsito Gastrointestinal/fisiologia , Masculino , Contração Muscular , Plexo Mientérico/imunologia , Plexo Mientérico/patologia , Neuroglia/imunologia , Neuroglia/patologia , Neurônios/imunologia , Neurônios/metabolismo , Neurônios/patologia , Ratos , Ratos Wistar , Subunidade beta da Proteína Ligante de Cálcio S100/metabolismoRESUMO
BACKGROUND: The prevalence of obesity has increased at alarming rates, particularly because of the increased consumption of high-fat diets (HFDs). The influence of HFDs on intrinsic innervation and the intestinal wall has not been fully characterized. The aim of this study was to investigate the morpho-quantitative aspects of myenteric neurons and the wall of the small intestine in mice fed a HFD. METHODS: Swiss mice were fed a HFD (59% kcal from fat) or standard chow (9% Kcal from fat) for 8 weeks. Segments of the duodenum, jejunum, and ileum were subjected to histological processing for morpho-quantitative examination of the intestinal wall and mucosal cells, and immunohistochemistry was performed to evaluate myenteric neurons. The data for each segment were compared between the groups using an unpaired Student's t-test or an equivalent nonparametric test. RESULTS: The HFD increased body weight and visceral fat and decreased the length of the small intestine and the circumference of the ileum. In the duodenum, the HFD increased the density of the nitrergic subpopulation and decreased the area of nitrergic neurons and vasoactive intestinal peptide (VIP) varicosities. In the jejunum, the density of the nitrergic subpopulation was increased and the neuronal areas of the general population, nitrergic subpopulation and (VIP) varicosities were reduced. In the ileum, the density of the general population and nitrergic subpopulation were increased and the neuronal areas of the general population, nitrergic subpopulation and (VIP) varicosities were reduced. The morphometric parameters of the villi, crypts, muscular layer and total wall generally increased in the duodenum and jejunum and decreased in the ileum. In the duodenum and jejunum, the HFD promoted a decreased in the proportion of intraepithelial lymphocytes. In the ileum, the proportion of intraepithelial lymphocytes and goblet cells reduced, and the enteroendocrine cells increased. CONCLUSIONS: The high-fat diet induces changes in the myenteric innervation of the small intestine, intestinal wall and mucosal cells responsible for the secretion of hormones and maintenance of the protective intestinal barrier. The morpho-quantitative data provide a basis for further studies to clarify the influence of HFD in the motility, digestive and absorptive capacity, and intestinal barrier.
Assuntos
Dieta Hiperlipídica/efeitos adversos , Mucosa Intestinal/patologia , Intestino Delgado/inervação , Intestino Delgado/patologia , Neurônios/química , Neurônios/patologia , Animais , Proliferação de Células , Duodeno/inervação , Duodeno/patologia , Duodeno/fisiopatologia , Células Enteroendócrinas , Células Caliciformes , Íleo/inervação , Íleo/patologia , Íleo/fisiopatologia , Mucosa Intestinal/fisiopatologia , Intestino Delgado/fisiopatologia , Jejuno/inervação , Jejuno/patologia , Jejuno/fisiopatologia , Contagem de Linfócitos , Masculino , Camundongos , Plexo Mientérico/patologia , Miosina Tipo V/análise , Neurônios Nitrérgicos/patologia , Obesidade/etiologia , Obesidade/patologia , Peptídeo Intestinal Vasoativo/análiseRESUMO
The effects of food restriction (FR) on the morphoquantitative aspects of the wall and myenteric neurons of the proximal colon in adult rats were analysed. FR was imposed by duplication of the experimental brood size in relation to the control brood during lactation. The FR group received a 50% reduction of food from weaning until 90 days of age. Samples of the colon underwent histological processing to morphometrically analyze the crypts, muscularis mucosae, tunica mucosa, and muscularis externa. We determined the number of goblet cells and serotoninergic enteroendocrine cells, and morphoquantitatively studied the myenteric neuronal population. FR caused hypertrophy in the tunica mucosa, increase in crypt depth and in the muscular layer of the mucosa, a decrease in the thickness of the tunica muscularis and in the number of goblet cells and an increase in serotoninergic cells. A higher neuronal density in the ganglia and a reduction of the cell profile area were observed in the FR group. FR imposed since lactation led to hypertrophy of the tunica mucosa, a reduction of neutral mucin production, atrophy of the tunica muscularis, and an increase in the survival neuronal in adult rats, attributable to an increase in the number of serotoninergic enteroendocrine cells in mucosa.