Avaliação de neurônios mioentéricos NADPH-diaforase positivos do íleo de ratos diabéticos suplementados com Acetil-L-Carnitina / Evaluation of positive NADPH-diaphorase myenteric neurons in diabetic rats supplemented with Acetyl-L-Carnitine

Objetivou-se avaliar a suplementação com acetil-L-carnitina (ALC) sobre os neurônios mioentéricos do íleo de ratos após a indução de diabetes. Foram usados animais diabéticos suplementados com ALC (DC), diabéticos (D), normoglicêmicos suplementados com ALC (CC) e normoglicêmicos (C). Neurônios NADPH-d foram quantificados e mensurados. Observou-se redução na glicemia e na ingestão de água no grupo DC. A densidade neuronal em 12,72mm² de íleo foi semelhante nos quatro grupos (p>0,05): DC (558,8 ± 220,2), D (513,4 ± 72,01), CC (645,2 ± 144,9) e C (934 ± 248,5). A área média do corpo celular dos neurônios (µm²) nos animais diabéticos, DC (303,9 ± 114,2) e D (285,4 ± 111,8), foram maiores que nos grupos normoglicêmicos, CC (173,6 ± 53,78) e C (158,4 ± 53,73). A área do íleo (mm²) também mostrou-se maior nos animais dos grupos diabéticos, DC (190,96) e D (171,62) quando comparados aos normoglicêmicos: CC (138,04) e C (130,06). Entretanto no grupo DC, ambas as áreas foram maiores que no D (P<0,05). Assim, pode se inferir discreto incremento na população neuronal. Os dados indicaram que a ALC não interferiu nos mecanismos que promovem aumento na produção de óxido nítrico (NO) pelos neurônios mioentéricos do íleo e que a maior dilatação do íleo no grupo DC poderia ser resultante de efeito colateral da dose de carnitina empregada.

The objective was to evaluate supplementation with acetyl-L-carnitine (ALC) on myenteric neurons of the ileum of rats after induction of diabetes. Diabetic animals supplemented with ALC (DC), diabetic (D), normoglycemic animals supplemented with ALC (CC) and normoglycemic (C) were used. NADPH-d neurons were quantified and measured. There was a reduction in blood glucose and water intake in the DC group. The neuronal density in 12.72mm² of ileum was similar in the four groups (p>0.05): DC (558.8 ± 220.2), D (513.4 ± 72.01), CC (645.2 ± 144.9) and C (934 ± 248.5). The mean cell body area of neurons (µm²) in diabetic animals, DC (303.9 ± 114.2) and D (285.4 ± 111.8), were greater than in the normoglycemic groups, CC (173.6 ± 53.78) and C (158.4 ± 53.73). The ileum area (mm²) was larger in animals of the diabetic groups, CD (190.96) and D (171.62) compared to the normoglycemic groups: CC (138.04) and C (130.04). However, in the DC group, both areas were larger than in D (p<0.05). Thus, a slight increase in neuronal population can be inferred. The data indicated that ALC did not interfere with mechanisms that promote an increase in the production of nitric oxide (NO) by myenteric neurons of the ileum and that the greater dilation of the ileum in the DC group could be the result of a side effect of the dose of carnitine used.

Ethyl Acetate Fraction from Trichilia catigua Confers Partial Neuroprotection in Components of the Enteric Innervation of the Jejunum in Diabetic Rats.

BACKGROUND/AIMS: Diabetes causes damage to the enteric nervous system. The enteric nervous system consists of neurons and enteric glial cells (EGCs). The present study evaluated the effects of an ethyl-acetate fraction (EAF) from Trichilia catigua (T. catigua; 200 mg/kg) on the total population of enteric neurons (HuC/D-immunoreactive [IR]) and EGCs (S100-IR and glial fibrillary acidic protein [GFAP]-IR) in the total preparation and jejunal mucosa in diabetic rats. METHODS: The animals were distributed into four groups: normoglycemic rats (N), diabetic rats (D), normoglycemic rats that received the EAF (NC), and diabetic rats that received the EAF (DC). The jejunum was processed for immunohistochemistry to evaluate HuC/D, S100, and GFAP immunoreactivity. The expression of S100 and GFAP proteins was also quantified by Western blot. RESULTS: The D group exhibited a decrease in the number of neurons and EGCs, an increase in the area of cell bodies, an increase in S100 protein expression, a decrease in GFAP protein expression, and a decrease in S100-IR and GFAP-IR EGCs in the jejunal mucosa. The DC group exhibited a decrease in the number of neurons and EGCs, a decrease in the area of cell bodies, a decrease in S100 and GFAP protein expression, and a decrease in S100-IR and GFAP-IR EGCs in the jejunal mucosa. The NC group exhibited maintenance of the number of neurons and EGCs, an increase in the area of cell bodies, and a decrease in S100 and GFAP protein expression. CONCLUSION: The EAF from T. catigua partially conferred protection against diabetic neuropathy in the enteric nervous system.

Antioxidant Systems as a Response to Midgut Cellular of Bombyx mori Lineu, 1758 (Lepidoptera: Bombycidae) Infection for Baculoviruses.

Bombyx mori nucleopolyhedrovirus (BmNPV) is a DNA virus that infects different tissues in Bombyx mori at immature stage. Caterpillars become infected after ingesting polyhedral occlusion bodies (POB) present in contaminated mulberry leaves and spread through the body after passing the epithelium of the midgut. As this organ is responsible for digestion, most absorption of nutrients requires an intact epithelium to maintain gastrointestinal physiology. Considering the importance of this organ in the feeding of caterpillars and in the production of quality silk threads, and because it is also the first barrier faced by the BmNPV, the study analyzed details of cytopathological events in the intestinal cells as well as evaluated the action of the antioxidant systems as a response to cellular infection. For this purpose, B. mori hybrid caterpillars of fifth instar were inoculated with a suspension of 7.8 × 107 POB ml-1 and, from the first to the eighth day post-inoculation (dpi), segments of the midgut were collected and processed for light and electronic microscopy. The nuclei of columnar cells showed polyhedric occlusion bodies in the seventh dpi and fragmentation of those cells, with peritrophic matrix disorganization. Analysis of antioxidant systems shows some moments of changes of the catalase enzymes and superoxide dismutase. Analysis of the cholinergic system revealed changes only at the beginning of the infection. Thus, the article acknowledges the antioxidant system as a barrier to stop viral infection, albeit it cannot stop infection from occurring, once a coevolutionary bond is maintained between virus and host.

Effects of quercetin-supplementation in NADH-diaphorase positive neurons subpopulations in the ileum of rats with experimental diabetes mellitus / Efectos de la suplementación con quercetina en subpoblaciones de neuronas NADH-diaforasa positivas en el Ileon de ratas con diabetes mellitus experimental

The effects of quercetin supplementation in NADH-diaphorase positive (NADH-d) neurons of streptozotocin-induced diabetic rats was carried in this study. Fifteen male rats were divided into three groups: normoglycemic (N), diabetic (D) and diabetic supplemented with quercetin (DQ). Whole mount preparations of the muscular layer of the ileum underwent NADH-d histochemistry for evidencing the NADH-d neuronal subpopulation. Quantitative analyzes were performed on 30 random fields, and morphometric analyzes in 100 neuronal bodies and nuclei per animal. The supplementation promoted a 44 % reduction in the neuronal density in D group when compared to N group (p <0.001); a 24.5 % reduction was observed in the DQ group when compared to N (p <0.01). Animals in D group presented an 18.7 % increase in the cell body areas of myenteric neurons when compared to N (p <0.001); DQ group showed a 14.2 % decrease in neuronal areas when compared to D (p <0.01); the nuclear area were similar among the three groups. We conclude that quercetin supplementation was positive for animals with diabetes mellitus.

Se estudiaron los efectos de la suplementación con quercetina en neuronas NADH-diaforasa positiva (NADH-d) de ratas diabéticas inducidas por estreptozotocina. Quince ratas machos se dividieron en tres grupos: normoglicémico (N), diabéticos (D) y diabéticos suplementados con quercetina (DQ). Las cortes montados de la capa muscular del íleon fueron sometidos a histoquímica de NADH-d para evidenciar la subpoblación neuronal NADH-d. Se realizaron análisis cuantitativos en 30 campos aleatorios y análisis morfométricos en 100 cuerpos y núcleos neuronales, por animal. La suplementación promovió una reducción del 44 % en la densidad neuronal en el grupo D cuando se comparó con el grupo N (p <0,001). Se observó una reducción del 24,5 % en el grupo DQ en comparación con N (p <0,01). Los animales del grupo D presentaron un aumento del 18,7 % en las áreas del cuerpo celular de las neuronas mientéricas cuando se compararon con N (p <0,001). El grupo DQ mostró una disminución de 14,2 % en las áreas neuronales en comparación con D (p <0,01). El área nuclear fue similar entre los tres grupos. Se concluye que la suplementación con quercetina fue positiva para animales con diabetes mellitus.

Antioxidant Effects of the Quercetin in the Jejunal Myenteric Innervation of Diabetic Rats.

PURPOSE: Enteric glial cells (EGCs) exert a critical role in the structural integrity, defense, and metabolic function of enteric neurons. Diabetes mellitus is a chronic disease characterized by metabolic disorders and chronic autonomic neuropathy. Quercetin supplementation, which is a potent antioxidant, has been used in order to reduce the effects of diabetes-induced oxidative stress. The purpose of this research was to investigate the effects of quercetin supplementation in the drinking water at a daily dose of 40 mg on the glial cells and neurons in the jejunum of diabetic rats. MATERIALS AND METHODS: Twenty 90-day-old male adult Wistar rats were split into four groups: normoglycemic control (C), normoglycemic control supplemented with quercetin (Q), diabetic (D), and diabetic supplemented with quercetin (DQ). After 120 days, the jejunums were collected, and immunohistochemical technique was performed to label S-100-immunoreactive glial cells and HuC/D-immunoreactive neurons. RESULTS: An intense neuronal and glial reduction was observed in the jejunum of diabetic rats. Quercetin displayed neuroprotective effects due to reduced cell body areas of neurons and glial cells in Q and DQ groups compared to their controls (C and D groups). Interestingly, quercetin prevented the glial and neuronal loss with a higher density for the HuC/D-immunoreactive neurons (23.06%) and for the S100-immunoreactive glial cells (14.55%) in DQ group compared to D group. CONCLUSION: Quercetin supplementation promoted neuroprotective effects through the reduction of neuronal and glial body areas and a slight prevention of neuronal and glial density reduction.

Morphoquantitative study of Rattus norvegicus submucosal plexus by different neuronal evidentiation histochemical techniques / Estudio morfocuantitativo del plexo submucoso de Rattus norvegicus por medio de diferentes técnicas histoquímicas para verificar características neuronales

Enteric nervous plexuses have been the object of several studies, specially the myenteric plexus whose studies describe its organization, functions and alterations. On the other hand, the submucosal plexus has been less studied and still needs descriptive studies. To analyze morphologically and quantitatively submucosal neurons of the jejunum of 90-day-old healthy rats using different techniques for neuronal staining as a way to provide normality data to compare with future experimental studies. Whole mount preparations of the jejunum were submitted to Giemsa, NADH-diaphorase and NADPH-diaphorase techniques to stain the total neuronal population, more metabolically active subpopulation and subpopulation of nitrergic neurons, respectively. Neurons of the submucosal plexus of adult rats are mainly organized in ganglia with varied sized and shapes. Giemsa technique stained 243.93 ± 7.68 neurons per mm2. Regarding the total population stained by Giemsa, NADH- diaphorase positive (139.09 ± 11.14/mm2) neurons represented 57 % and NADPH-diaphorase positive (18.17 ± 0.28/mm2) represented 7.5 %. The area of the cell body was bigger in nitrergic neurons (412.29 ± 150.22) than in the ones stained by Giemsa (254.71 ± 63.32) and NADH-diaphorase positive (243.98 ± 123.82).

El plexo nervioso entérico ha sido objeto de varios estudios, especialmente el plexo mientérico, cuyos estudios consisten en describir su organización, funciones y alteraciones. Por otro lado, el plexo submucoso ha sido menos investigado y todavía necesita estudios descriptivos. Para analizar morfológica y cuantitativamente las neuronas de la submucosa del yeyuno de ratas de 90 días de edad, se realizaron diferentes técnicas de tinción neuronales, en animales sanos, como una forma de proporcionar datos de normalidad y compararlo con futuros estudios experimentales. Se realizaron montajes con preparados enteros del yeyuno que fueron sometidos a las técnicas de Giemsa, de NADPH-diaforasa y NADH-diaforasa para teñir la población total neuronal, subpoblación más activa metabólicamente y subpoblación de neuronas nitrérgicas, respectivamente. Las neuronas del plexo submucoso de ratas adultas se organizan principalmente en los ganglios con variaciones de tamaño y formas. Con la técnica de Giemsa se tiñeron 243.93±7.68 neuronas por mm2. Con respecto a la población total teñida con Giemsa, fueron positivas para NADH- diaforasa en 139.09 ±11.14 / mm2 neuronas, representando el 57% y fueron positivas para NADPH-diaforasa en 18,17 ± 0,28 / mm2 neuronas, lo que representó el 7,5%. El área del cuerpo celular fue mayor en neuronas nitrérgicas (412,29 ± 150.22) que en las teñidas con Giemsa (254,71 ± 63,32) y NADH-diaforasa positivas (243,98 ± 123,82).

Chronic infection with Toxoplasma gondii induces death of submucosal enteric neurons and damage in the colonic mucosa of rats.

Intestinal epithelial secretion is coordinated by the submucosal plexus (SMP). Chemical mediators from SMP regulate the immunobiological response and direct actions against infectious agents. Toxoplasma gondii is a worldwide parasite that causes toxoplasmosis. This study aimed to determine the effects of chronic infection with T. gondii on the morphometry of the mucosa and the submucosal enteric neurons in the proximal colon of rats. Male adult rats were distributed into a control group (n = 10) and an infected group (n = 10). Infected rats received orally 500 oocysts of T. gondii (ME-49). After 36 days, the rats were euthanized and samples of the proximal colon were processed for histology to evaluate mucosal thickness in sections. Whole mounts were stained with methylene blue and subjected to immunohistochemistry to detect vasoactive intestinal polypeptide. The total number of submucosal neurons decreased by 16.20%. Vasoactive intestinal polypeptide-immunoreactive neurons increased by 26.95%. Intraepithelial lymphocytes increased by 62.86% and sulfomucin-producing goblet cells decreased by 22.87%. Crypt depth was greater by 43.02%. It was concluded that chronic infection with T. gondii induced death and hypertrophy in the remaining submucosal enteric neurons and damage to the colonic mucosa of rats.

Vitamins C and E (ascorbate/α-tocopherol) provide synergistic neuroprotection in the jejunum in experimental diabetes.

The present study evaluated the synergistic effects of the association of ascorbic acid and α-tocopherol on myenteric in the jejunum of diabetic rats. The rats were randomly divided into four equal groups: untreated normoglycemic (UC), untreated diabetic (UD), ascorbic acid and α-tocopherol-treated normoglycemic (CAE) and ascorbic acid and α-tocopherol-treated diabetic (DAE). The rats from the CAE and DAE group received supplementation with ascorbic acid (1g/L in water) and α-tocopherol (1% in chow). At 210-days-old, the animals were sacrified and their jejunum was collected and submitted to immunohistochemistry. Quantitative and/or morphometric analysis were performed. Supplementation with ascorbic acid and α-tocopherol prevented the cell loss of myenteric neurons expressing HuC/D and TrkA in an equivalent proportion. We also observed a reduction of the CGRP nerve fiber varicosities and the prevention of the increased cell body size of submucosal VIP neurons (p<0.05). The association of ascorbic acid and α-tocopherol reduced the deleterious effects of diabetes promoting protection on the enteric neurons.

Myosin Va but Not nNOSα is Significantly Reduced in Jejunal Musculomotor Nerve Terminals in Diabetes Mellitus.

Nitric oxide (NO) mediated slow inhibitory junction potential and mechanical relaxation after electrical field stimulation (EFS) is impaired in diabetes mellitus. Externally added NO donor restore nitrergic function, indicating that this reduction result from diminution of NO synthesis within the pre-junctional 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 16 weeks after induction of diabetes by low dose streptozotocin (STZ) 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 pre-junctional NO synthesis during EFS of diabetic gut neuromuscular strips despite presence of the nitrergic synthetic enzyme nNOSα.

Efeitos da suplementação com ácido ascórbico sore os neurônios mioentéricos doo estômago de ratos diabeticos / Effcts of ascorbbic acid supplementation on myenterc neurons in thhe stomach of diabetic rats

Diabetes mellitus (DM) é uma desordem metabólica caracterizada pelo aumento nos níveis de glicose no sangue. O DM pode promover alterações degenerativas do sistema nervoso entérico, porque a hiperglicemia aumenta a formação de espécies reativas de oxigênio e, consequentemente, aumenta o estresse oxidativo. O objetivo deste estudo foi avaliar o efeito da suplementação com ácido ascórbico (AA) nos neurônios NADH-diaforase reativos (NADH-dr) do plexo mioentérico do estômago de ratos com diabetes induzida por estreptozootocina. Para tanto, 15 animais foram divididos em três grupos (n = 5): Grupo C (ratos normoglicêmicos), Grupo D (ratos diabéticos) e DS Grupo (ratos diabéticos tratados com ácido ascórbico). A técnica histoquímica da NADH-diaforase foi empregada e, a densidade neuronal (neurónios/mm2) e a área do perfil dos corpos celulares de 500 neurônios NADH-d de todos os grupos foi investigada. A densidade neuronal no grupo DS foi maior do que nos grupos C (P> 0,05) e D (P <0,05). A área dos neurônios mioentéricos (NADH-dr) foi menor nos grupos C (P <0,05) e DS (P> 0,05) que o grupo D. Estes resultados sugerem que a suplementação com ascórbico promoveu um efeito neuroprotetor nos NADH-dr neurônios mioentéricos do estômago dos ratos diabéticos.

Diabetes mellitus (DM) is a metabolic disorder characterized by an increase in blood glucose levels. DM can promote degenerative changes in the enteric nervous system due to the hyperglycemia increasing the formation of reactive oxygen species and, consequently increasing the oxidative stress. The aim of this study was to evaluate the effect of ascorbic acid (AA) supplementation on the NADH-diaphorase reactive neurons (NADH-dr) in the myenteric plexus of the stomach of streptozotocin-induced diabetic rats. In order to do this, 15 animals were divided into three groups (n=5): C Group (normoglicemic rats), D Group (diabetic rats) and DS Group (diabetic rats treated with ascorbic acid). The NADH-d histochemistry technique was employed and the neuronal density (neurons/mm2) and the cell body profile area of 500 NADH-d-stained neurons from all groups were investigated. The neuronal density in the DS group was higher than in the C (P>0.05) and D (P<0.05) groups. The area of the (NADH-dr) myenteric neurons was smaller in the C (P<0.05) and DS (P>0.05) groups than in the D group. These results suggest that ascorbic supplementation promotes a neuroprotective effect on the NADH-drmyenteric neurons from the stomach of diabetic rats.

Neuroprotection and neurodegeneration in submucosal VIP-IR neurons in the jejunum of ascorbic acid supplemented aging Wistar rats.

The present work studied the effects of ascorbic acid supplementation (1 mg/ml in water daily) on submucosal vasoactive intestinal polypeptide-immunoreactive (VIP-IR) neurons in the jejunum of aging rats. Twenty-five male rats were divided into the following groups: Y90 (young, 90-day-old rats), A345 (aged, 345-day-old rats), A428 (aged, 428-day-old rats), AA345 (ascorbic acid-supplemented rats, 90-345-day old), and AA428 (ascorbic acid-supplemented rats, 90-428-day old). Whole mounts of the submucosal layer were subjected to immunohistochemistry for determination of VIP-IR. Morphometric analyses were carried out in 100 submucosal VIP-IR neuron cell bodies from each group. At 345 days, neurons from supplemented animals were larger than those of non-supplemented animals of the same age. These results indicate that ascorbic acid neutralized free radicals and played a neuroprotective role. At 428 days, no significant differences between cell body areas were seen with or without ascorbic acid supplementation, indicating that, from a certain age onward, the role of ascorbic acid as a VIP-IR antioxidant was reduced. This supposition is supported by the fact that both supplemented and non-supplemented animals had higher blood concentrations of ascorbic acid on Day 428 compared with Day 345. The possible neuroprotective and neurodegenerative effects of ascorbic acid appear to depend on the age of the animals, dose, and its interaction with other antioxidants.

Immunohistochemical study of vasoactive intestinal peptide (VIP) enteric neurons in diabetic rats supplemented with L-glutamine.

The purpose of this work was to study the area of the varicosities of nerve fibers of myenteric neurons immunoreactive to vasoactive intestinal peptide (VIP-IR) and of the cell bodies of VIP-IR submucosal neurons of the jejunum of diabetic rats supplemented with 2% L-glutamine. Twenty male rats were divided into the following groups: normoglycemic (N), normoglycemic supplemented with L-glutamine (NG), diabetic (D) and diabetic supplemented with L-glutamine (DG). Whole-mounts of the muscle tunica and the submucosal layer were subjected to the immunohistochemical technique for neurotransmitter VIP identification. Morphometric analyses were carried out in 500 VIP-IR cell bodies of submucosal neurons and 2000 VIP-IR varicosities from each group. L-Glutamine supplementation to the normoglycemic animals caused an increase in the areas of the cell bodies (8.49%) and varicosities (21.3%) relative to the controls (P < 0.05). On the other hand, there was a decrease in the areas of the cell bodies (4.55%) and varicosities (28.9%) of group DG compared to those of group D (P < 0.05). It is concluded that L-glutamine supplementation was positive both to normoglycemic and diabetic animals.

Effects of insulin treatment on HuC/HuD, NADH diaphorase, and nNOS-positive myoenteric neurons of the duodenum of adult rats with acute diabetes.

We carried out this investigation with the purpose of verifying whether insulin treatment prevents changes in the density of myoenteric neurons of the duodenum of Wistar rats with streptozotocin short-term diabetes. The animals from the diabetic group (D) lost more weight than the controls (group C), while the insulin treatment (group T) prevented weight loss in three animals and increased visceral fat in all of the animals of this group. Insulin treatment did not prevent the early loss of HuC/HuD myoenteric neurons. The density of nNOS-positive neurons did not change significantly in groups D and T. The density of NADHd-positive neurons in these groups was greater than in group C, indicating that short-term diabetes increases the activity of respiratory chain enzymes.

Myenteric neurons and intestinal mucosa of diabetic rats after ascorbic acid supplementation.

AIM: To investigate the effect of ascorbic acid (AA) dietary supplementation on myenteric neurons and epithelial cell proliferation of the jejunum of adult rats with chronic diabetes mellitus. METHODS: Thirty rats at 90 d of age were divided into three groups: Non-diabetic, diabetic and diabetic treated with AA (DA) (1 g/L). After 120 d of treatment with AA the animals were killed. The myenteric neurons were stained for myosin-V and analyzed quantitatively in an area of 11.2 mm(2)/animal. We further measured the cellular area of 500 neurons per group. We also determined the metaphasic index (MI) of the jejunum mucosa layer of about 2500 cells in the intestinal crypts, as well as the dimensions of 30 villi and 30 crypts/animal. The data area was analyzed using the Olympus BX40 microscope. RESULTS: There was an increase of 14% in the neuronal density (792.6 +/- 46.52 vs 680.6 +/- 30.27) and 4.4% in the cellular area (303.4 +/- 5.19 vs 291.1 +/- 6.0) respectively of the diabetic group treated with AA when compared to control diabetic animals. There were no significant differences in MI parameters, villi height or crypt depths among the groups. CONCLUSION: Supplementation with AA in the diabetic animal promoted moderate neuroprotection. There was no observation of alteration of the cellular proliferation of the jejunum mucosa layer of rats with chronic diabetes mellitus with or without supplementation with AA.

Vitamin E supplementation in rats with experimental diabetes mellitus: analysis of myosin-V and nNOS immunoreactive myenteric neurons from terminal ileum.

The effect of vitamin E (1 g/kg body weight) supplementation on myosin-V and neuronal nitric oxide synthase (nNOS) immunoreactive myenteric neurons from the ileum of diabetic rats was investigated in the present study. Forty animals were divided into the following groups: normoglycemics (N), normoglycemics treated with vitamin E (NE), diabetics (D), and diabetics treated with vitamin E (DE). Quantitative and morphometric analyses were performed. The area of the tertiary plexus was also determined. Diabetes produced a 24% reduction in the number of myosin-V neurons in group D compared with group N, an effect that was accompanied by an increase in the tertiary plexus area (P < 0.05). Neuronal density was 27% higher in group NE than group N (P < 0.05). Nitrergic neuronal density was not altered as a consequence of either diabetes or vitamin E treatment. Myosin-V and nNOS immunoreactive neuronal cell body area increased significantly in group NE. The area of myosin-V and nNOS myenteric neurons also increased in group D. Vitamin E treatment (group DE) increased only the size of nitrergic neurons. The present results suggest that vitamin E elicited a neuroprotective and neurotrophic effect on the natural aging process, but with regard to diabetes, vitamin E supplementation exerted a neurotrophic effect only on nitrergic neurons.

Quantitative Study of the Myenteric Plexus of the Descending Colon of Young Rats Subjected to Intense Protein Deficiency / Estudio Cuantitativo del Plexo Mientérico del Colon Descendente de Ratas Jóvenes Sometidas a Intensa Deficiencia Proteica

We studied the effects of a severely hypoproteic diet on the quantitative aspects of the myenteric plexus of the descending colon of young rats. Eighteen rats were divided into two groups, one of them being fed with a chow having 26% protein (control) and the other with a chow having 4% protein, balanced for minerals and vitamins, during 12 weeks. The whole-mounts of the descending colon had their myenteric neurons stained either with Giemsa or NADPH diaphorase. The rats from the experimental group had deficits of body weight (54.23%) and area of the descending colon (48.14%); additionally, we observed that there was no alteration in the total number of neurons of the colon, but a decrease in the number of NADPH-diaphorase positive neurons (37.80%). The implications of these results concerning the priority that some cellular types may have when nutrients are less available are discussed.

Estudiamos los efectos crónicos de una dieta severamente hipoproteica sobre los aspectos cuantitativos del plexo mientérico del colon descendente de ratones jóvenes. 18 ratones fueron divididos en dos grupos, a uno de estos grupos se le dió ración con contenido proteico del 26% (control) y al otro, ración con contenido proteico del 4%. Se mantuvo el balance vitamínico y mineral, durante 12 semanas. Elaboramos los preparados de membrana del colon descendente y marcamos las neuronas del plexo mientérico con Giemsa y NADPH-diaforasa. Los ratones del grupo experimental presentaron déficit de peso corporal (54,23%) y del área del colon descendente (48,14%); además, observamos que no hubo alteración en el número total de neuronas en todo el colon; sin embargo, hubo una disminución en la marcación de neuronas NADPH-diaforasa positivas (37,80%). Los resultados son discutidos, respecto a la prioridad que ciertos tipos celulares pudiesen tener, con la menor disponibilidad de nutrientes.

Morphological and quantitative analyses of the NADH-d myenteric neurons of the jejunum of rats submitted to experimental chronic alcoholism / Análisis Morfológico y Cuantitativo de de Neuronas Mientéricas NADH-d del Yeyuno de Ratas Sometidas a Alcoholismo Crónico Experimental

El objetivo del trabajo fue verificar, durante un período experimental de 210 días, los posibles efectos del etanol sobre la morfología y densidad de las neuronas mientéricas NADH-diaforasa, en el yeyuno de ratas alcohólicas. Utilizamos 10 animales (Rattus norvegicus) separadas en dos grupos: el control (n=5) que recibió una dieta proteica normal (22 por ciento) y agua ad libitum; el otro, alcohólico, que recibió dieta proteica normal NUVILAB (22 por ciento) y brandy de azúcar de caña diluido a 30 Gay Lussac (30 v/v). El segmento de yeyuno fue obtenido y sometido a técnicas histoquímicas para teñir las células nerviosas. La observación a través de microscopía de luz mostró que no hubo diferencias morfológicas de importancia entre las neuronas del grupo control y el sometido a alcoholismo. El recuento neuronal en el grupo control, llevado a cabo en 40 campos microscópicos (8,96 µm2), de las regiones mesentérica y antimesentérica, determinó 1.131 y 693 neuronas, respectivamente, mientras que en el grupo alcohólico se encontraron 1.229 y 860 neuronas, respectivamente. El incremento significativo en el número de neuronas en la región mesentérica, en el grupo de las ratas alcohólicas, es debido a un crecimiento físico menor de esos animales comparados con el grupo control. El etanol causó malnutrición y consecuentemente, las ratas alcohólicas mostraron una densidad neuronal más amplia debido a una dispersión menor.

The objective of our work was to verify, during an experimental period of 210 days, the possible effects of the ethanol on the morphology and density of the NADH-diaforase myenteric neurons in the jejunum of alcoholic rats. We used 10 animals (Rattus norvegicus) separated in 2 groups: the controls (n=5), that received a normal proteic diet (22%) and water ad libitum; the alcoholic, that received NUVILAB normal proteic chow (22%) and sugar cane brandy diluted at 30 Gay Lussac (30 v/v). The jejunum segment was collected and submitted to the histochemical technique to stain the nervous cells and, then, to the elaboration of membrane whole mounts. The observation through light microscopy showed that there are no expressive morphologic differences between the ganglia of neurons of the control and alcoholic rats. The counting of neurons, carried out in 40 microscopic fields (8.96µm2) in the control group, at the mesenteric and antimesenteric regions, found 1,131 and 693 neurons respectively, while, the alcoholic group found 1,229 and 860 neurons. The significant increase in the number of neurons in the mesenteric region, in the alcoholic rats, is due to the smaller physical growth of those animals when compared to the controls. The ethanol caused malnutrition and consequently the alcoholic rats showed a larger neuronal density due to its smaller dispersion.

Aspectos morfoquantitativos de neurônios mioentéricos NADPH-diaforase positivos do estômago de ratos diabéticos / Morphoquantitative aspects of the NADPH-diaphorase positive myenteric neurons from the stomach of diabetic rats

O presente estudo teve por objetivo analisar as características morfoquantitativas de neurônios mioentéricos NADPH-diaforase positivos do estômago de ratos diabéticos. O estômago de cinco ratos normoglicêmicos e de cinco ratos diabéticos foi submetido a preparados de membrana corados pela técnica histoquímica da NADPH-diaforase. Verificou-se, nos animais diabéticos, diminuição do peso corporal, aumento do consumo diário de água, da glicemia em jejum e da hemoglobina glicada. Com os dados obtidos, foi observado aumento significante na densidade e nas áreas dos perfis celulares neuronais da região pilórica do estômago dos ratos diabéticos...

Profile of the cell body of nadh-diaphorase positive myenteric neurons from the stomach of rats (Rattus norvegicus) subjected to chronic alcoholism

O objetivo do trabalho foi comparar o perfil dos corpos celulares dos neurônios mioentéricos NADH-diaforase positivos do estômago de ratos. Utilizou-se 10 animais (Rattus norvegicus), provenientes dos grupos: a) controle (n=5), que durante 210 dias receberam, ad libitum, dieta com teor protéico normal (22 por cento) e água; e b) experimental (n=5), que durante 210 dias receberam, ad libitum, ração com teor protéico normal (22 por cento) e aguardente-de-cana diluída a 30 Gay Lussac (30º v/v). Os estômagos coletados foram submetidos à técnica de evidenciação neuronal. A mensuração do perfil dos corpos celulares dos neurônios (n=1.000) foi através de um Sistema Computadorizado de Análise de Imagem. O perfil dos corpos celulares dos neurônios do grupo controle ficou entre 60,16 a 638,64 m2. No grupo experimental variou de 40,84 a 599,15 µm2. Constatamos redução significante no tamanho do corpo celular, aumento de neurônios pequenos e diminuição de neurônios grandes

Avaliação quantitativa e mofométrica dos neurônios mioentéricos da região agrandular do estômago de ratos com Diabetes Mellitus induzido por estreptozootocina e suplementados com ácido ascórbico / Quantitative and morphometric evaluation of myenteric neurons of the forestomach of streptozotocin-induced diabetic rats supplemented with ascorbic acid

O presente trabalho teve como objetivos investigar possíveis alterações no número e a área do corpo celular dos neurônios mioentéricos NADH-diaforase reativos (NADH-dr) da região aglandular do estômago de ratos diabéticos e o efeito da suplementação com AA (1g/L de água) nos referidos parâmetros. Para tanto, 15 ratos (Rattus norvegicus) foram separados em três grupos (n = 5): controle (C); diabético (D); e diabético suplementado com AA (DS). O DM foi induzido por estreptozootocina (35 mg/kg de peso corporal). Após 120 dias de experimento, os animais foram anestesiados para obtenção do estômago. Os neurônios mioentéricos foram evidenciados pelo método da NADH-diaforase. Por meio de microscópio de luz foram contados os neurônios NADH-dr e, pelo programa computadorizado para análise de imagens, foi mensurado o perfil do corpo celular (PCC) desses neurônios. O número de neurônios NADH-dr não variou significativamente entre os três grupos estutados (P>0,05). A média dos PCCs foi maior (P<0,05) para os neurônios dos grupos D e DS do que para o grupo C. Ocorreu aumento na incidência de neurônios com PCC superior a 200 µm2 no grupo D quando comparada aos grupos DS e C. Os resultados sugerem que a suplementação com AA teve efeito neuroprotetor sobre os neurônios mioentéricos NADH-dr representado pela diminuição da freqüência de neurônios grandes na região aglandular A e B do grupo DS