Chronic ingestion of deoxynivalenol-contaminated diet dose-dependently decreases the area of myenteric neurons and gliocytes of rats.

BACKGROUND: Deoxynivalenol (DON), a mycotoxin produced by Fusarium spp., is commonly found in cereals ingested by humans and animals. Its ingestion is correlated with hepatic, hematologic, renal, splenic, cardiac, gastrointestinal, and neural damages, according to dose, duration of exposure and species. In this work, the effects of the ingestion of DON-contaminated diet at concentrations considered tolerable for human and animal intake were assessed. METHODS: Male Wistar rats aging 21 days were allotted to five groups that were given, for 42 days, diets contaminated with different concentrations of DON (0, 0.2, 0.75, 1.75, and 2 mg kg-1 of chow). Food ingestion, bodyweight, oxidative status and morphometric analyses of gliocytes, and neurons of jejunal myenteric ganglia were recorded. KEY RESULTS: At these concentrations, there was no food rejection, decrease in bodyweight gain, changes in oxidative status, or loss of either neurons or gliocytes. However, DON decreased gliocyte area, general neuronal population, nitrergic, cholinergic and NADH-diaphorase positive subpopulations and, as a result, ganglion area. CONCLUSIONS & INFERENCES: It was concluded that, even in the absence of visible effect, DON exposure reduces cell body area of gliocytes and neurons of the myenteric plexus of the rat jejunum.

Antioxidant Action of an Aqueous Extract of Royal Sun Medicinal Mushroom, Agaricus brasiliensis (Agaricomycetes), in Rats with Adjuvant-Induced Arthritis.

The purpose of this study was to evaluate possible effects of the administration of an aqueous Agaricus brasiliensis extract on the oxidative state of the liver, brain, and plasma in adjuvant-induced arthritic rats, a model for human rheumatoid arthritis. Daily doses of 400 mg · kg-1 were administered by gavage for 23 days. This treatment produced significant diminutions in protein carbonylation and lipid damage in the liver, brain, and plasma. It also diminished the tissue reactive oxygen species and increased the antioxidant capacity of the plasma. Antioxidant defenses, which are diminished by arthritis, were improved by treatment with the A. brasiliensis extract, as revealed by preservation of the reduced glutathione and protein thiol levels and by the tendency of the activities of some antioxidant enzymes to normalize. The increased glucose-6-phosphate dehydrogenase activity was also almost normalized by the treatment. In addition, there were indications that A. brasiliensis can inhibit the initiation of structural events that can lead to hepatocyte necrosis. In conclusion, A. brasiliensis aqueous preparations can, in principle, be visualized as potential auxiliaries in the treatment of patients with rheumatoid arthritis as a result of their capacity to reduce oxidative stress. This effect was exerted in multiple organs, as can be judged from the results obtained in the liver, brain, and plasma. The continuous ingestion of A. brasiliensis as specific preparations or as a food supplement can possibly help to attenuate the systemic effects of rheumatoid arthritis and improve the quality of life of patients affected by this disease.

Aqueous Extract of Agaricus blazei Murrill Prevents Age-Related Changes in the Myenteric Plexus of the Jejunum in Rats.

This study evaluated the effects of the supplementation with aqueous extract of Agaricus blazei Murrill (ABM) on biometric and blood parameters and quantitative morphology of the myenteric plexus and jejunal wall in aging Wistar rats. The animals were euthanized at 7 (C7), 12 (C12 and CA12), and 23 months of age (C23 and CA23). The CA12 and CA23 groups received a daily dose of ABM extract (26 mg/animal) via gavage, beginning at 7 months of age. A reduction in food intake was observed with aging, with increases in the Lee index, retroperitoneal fat, intestinal length, and levels of total cholesterol and total proteins. Aging led to a reduction of the total wall thickness, mucosa tunic, villus height, crypt depth, and number of goblet cells. In the myenteric plexus, aging quantitatively decreased the population of HuC/D(+) neuronal and S100(+) glial cells, with maintenance of the nNOS(+) nitrergic subpopulation and increase in the cell body area of these populations. Supplementation with the ABM extract preserved the myenteric plexus in old animals, in which no differences were detected in the density and cell body profile of neurons and glial cells in the CA12 and CA23 groups, compared with C7 group. The supplementation with the aqueous extract of ABM efficiently maintained myenteric plexus homeostasis, which positively influenced the physiology and prevented the death of the neurons and glial cells.

Intestinal morphology adjustments caused by dietary restriction improves the nutritional status during the aging process of rats.

During the aging process, the body's systems change structurally and loss of function can occur. Ingesting a smaller amount of food has been considered a plausible proposal for increased longevity with the quality of life. However, the effects of dietary restriction (DR) during aging are still poorly understood, especially for organs of the digestive system. This study aimed to describe the body weight, oxidative status and possible morphological changes of the intestinal wall of rats submitted to DR during the aging process (7 to 18months old). Twelve 7-month-old male Wistar rats fed ad libitum since birth were assigned to two groups: control group (CG, n=6) fed ad libitum from 7 to 18months old; and dietary restriction group (DRG, n=6) fed 50% of the amount of chow consumed by the CG from 7 to 18months old. The body weight, feed and water intake were monitored throughout the experiment. Blood, periepididymal adipose tissue (PAT) and retroperitoneal adipose tissue (RAT), and the small intestine were collected at 18months old. The blood was collected to evaluate its components and oxidative status. Sections from the duodenum and ileum were stained with HE, PAS and AB pH2.5 for morphometric analyses of the intestinal wall components, and to count intraepithelial lymphocytes (IELs), goblet cells and cells in mitosis in the epithelium. DR rats showed a reduction in weight, naso-anal length, PAT, RAT and intestinal length; however, they consumed more water. Blood parameters indicate that the DR rats remained well nourished. In addition, they showed lower lipid peroxidation. Hypertrophy of the duodenal mucosa and atrophy of the ileal mucosa were observed. The number of goblet cells and IELs was reduced, but the mitotic index remained unaltered in both duodenum and ileum. In conclusion, 50% dietary restriction for rats from 7 to 18months old contributed to improving their nutritional parameters but, to achieve this, adjustments were required in the structure of the body weight and morphology of the small intestine.

Dietary restriction interferes with oxidative status and intrinsic intestinal innervation in aging rats.

OBJECTIVES: To evaluate the effects of dietary restriction on oxidative status, the HuC/D-neuronal nitric oxide synthase (nNOS) myenteric neuron population, HuC/D-S100 glial cells, and the morphometry of the small intestine in rats at various ages. METHODS: Fifteen Wistar rats were divided into 7-and 12-mo-old control groups and a 12-mo-old experimental group subjected to dietary restrictions (50% of normal ration) for 5 mo. At 7 and 12 mo of age, the animals were anesthetized, and blood was collected to assess the biochemical components and oxidative status. Ileum samples were subjected to double-marker (HuC/D-nNOS and HuC/D-S100) immunostaining and histologic processing to morphometrically analyze intestinal wall elements and determine the metaphase index and rate of caliciform cells. The data were subjected to analysis of variance and the Tukey post hoc test with a 5% significance level. RESULTS: Age affected the oxidative status by increasing lipid peroxidation, with no effect on blood components, intrinsic innervation, and intestinal wall elements. The animals subjected to dietary restriction showed improved levels of total cholesterol, triacylglycerols, and oxidative status, with no changes in the nNOS neuron population. However, the dietary restriction dramatically decreased the glial and HuC/D myenteric populations, led to atrophy of the neuronal cell body, induced glial hypertrophy, and decreased the thickness of the intestinal wall. CONCLUSION: The high oxidative status of the aging animals was reversed by dietary restriction, which also lowered cholesterol and triacylglycerol levels. The present dietary restriction elicited morpho-quantitative changes in the myenteric plexus and histology of the ileum, with likely effects on intestinal functions.