Fatty acids uptake and oxidation are increased in the liver of rats with adjuvant-induced arthritis.

Severe rheumatoid cachexia is associated with pronounced loss of muscle and fat mass in patients with advanced rheumatoid arthritis. This condition is associated with dyslipidemia and predisposition to cardiovascular diseases. Circulating levels of triglycerides (TG) and free fatty acids (FFA) have not yet been consistently defined in severe arthritis. Similarly, the metabolism of these lipids in the arthritic liver has not yet been clarified. Aiming at filling these gaps this study presents a characterization of the circulating lipid profile and of the fatty acids uptake and metabolism in perfused livers of rats with adjuvant-induced arthritis. The levels of TG and total cholesterol were reduced in both serum (10-20%) and liver (20-35%) of arthritic rats. The levels of circulating FFA were 40% higher in arthritic rats, possibly in consequence of cytokine-induced adipose tissue lipolysis. Hepatic uptake and oxidation of palmitic and oleic acids was higher in arthritic livers. The phenomenon results possibly from a more oxidized state of the arthritic liver. Indeed, NADPH/NADP+ and NADH/NAD+ ratios were 30% lower in arthritic livers, which additionally presented higher activities of the citric acid cycle driven by both endogenous and exogenous FFA. The lower levels of circulating and hepatic TG possibly are caused by an increased oxidation associated to a reduced synthesis of fatty acids in arthritic livers. These results reveal that the lipid hepatic metabolism in arthritic rats presents a strong catabolic tendency, a condition that should contribute to the marked cachexia described for arthritic rats and possibly for the severe rheumatoid arthritis.

Copaiba Oil Decreases Oxidative Stress and Inflammation But not Colon Damage in Rats with TNBS-Induced Colitis.

BACKGROUND: TNBS-induced colitis is an experimental immunopathology in rats that shares many features with human inflammatory bowel diseases. Copaiba oleoresin is extracted from plants of the genus Copaifera and is shown to reduce inflammation. OBJECTIVE: The aim of this study was to investigate the action of copaiba oil (C. reticulata Ducke) on inflammation and oxidative status in the distal colon of colitic rats. METHODS: Acute and subchronic colitis were induced in Wistar rats by an intracolonic enema with 2,4,6-trinitrobenzenesulfonic acid (TNBS). The colonic morphology was assessed by histological analysis and the oxidative stress parameters were measured in the intestinal homogenate. The liver damage markers were measured in the plasma. Control and colitic rats were orally treated either with one single dose (acute colitis) of copaiba oil (1.15 g Kg-1) or once a day during seven days (subchronic colitis). RESULTS: The intestinal morphology was severely modified by acute and subchronic colitis, as indicated by the intramural infiltration of polymorphonuclear cells and the increased thickness of all colon layers. The levels of TBARS, protein carbonyl groups and reactive oxygen species (ROS) were increased in the intestine of colitic rats. Copaiba oil did not attenuate the inflammatory damage in acute and subchronic colitis, but it decreased the activity of myeloperoxidase, leukocyte infiltration and oxidative stress in the colon. The level of plasma bilirubin and the activity of alkaline phosphatase were both increased in treated healthy and colitic rats. CONCLUSION: Copaiba oil decreased oxidative stress and inflammation but did not prevent intestinal damage in the colon of colitic rats. The alterations of plasma markers of hepatic damage caused by the oil seem to be associated to its harmful action on the liver.

Effects of the continuous administration of an Agaricus blazei extract to rats on oxidative parameters of the brain and liver during aging.

An investigation of the effects of an aqueous extract of Agaricus blazei, a medicinal mushroom, on the oxidative state of the brain and liver of rats during aging (7 to 23 months) was conducted. The treatment consisted in the daily intragastric administration of 50 mg/kg of the extract. The A. blazei treatment tended to maintain the ROS contents of the brain and liver at lower levels, but a significant difference was found only at the age of 23 months and in the brain. The TBARS levels in the brain were maintained at lower levels by the A. blazei treatment during the whole aging process with a specially pronounced difference at the age of 12 months. The total antioxidant capacity in the brain was higher in treated rats only at the age of 12 months. Compared with previous studies in which old rats (21 months) were treated during a short period of 21 days with 200 mg/kg, the effects of the A. blazei extract in the present study tended to be less pronounced. The results also indicate that the long and constant treatment presented a tendency of becoming less effective at ages above 12 months.

Food restriction beginning at lactation interferes with the cellular dynamics of the mucosa and colonic myenteric innervation in adult rats.

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.

Ultraviolet (UVB and UVA) photoprotector activity and percutaneous penetration of extracts obtained from Arrabidaea chica.

The aim of this work is to investigate the photoprotection activity and toxicity level of formulations containing the extract and its fractions obtained from leaves of Arrabidaea chica. The ex vivo percutaneous penetration of the extract was evaluated using the photoacoustic spectroscopy technique. The formulation presented optical absorption in the ultraviolet region, including UVA and UVB. This formulation was obtained without adding inorganic UV filters, as is frequently used in commercial sunscreens. The results showed a penetration rate similar to those of commercial sunscreens with its presence on the skin surface at least 180 min after the application. This formulation presented no toxic effects evaluated using hematological, biochemical, and histological assays. The results suggest that the formulation from the leaves of A. chica provides substantial protection against UVA + UVB radiation with a possible advantage of being natural and free of inorganic compounds compared with the majority of available commercial sunscreens.

Effects of an Agaricus blazei aqueous extract pretreatment on paracetamol-induced brain and liver injury in rats.

The action of an Agaricus blazei aqueous extract pretreatment on paracetamol injury in rats was examined not only in terms of the classical indicators (e.g., levels of hepatic enzymes in the plasma) but also in terms of functional and metabolic parameters (e.g., gluconeogenesis). Considering solely the classical indicators for tissue damage, the results can be regarded as an indication that the A. blazei extract is able to provide a reasonable degree of protection against the paracetamol injury in both the hepatic and brain tissues. The A. blazei pretreatment largely prevented the increased levels of hepatic enzymes in the plasma (ASP, ALT, LDH, and ALP) and practically normalized the TBARS levels in both liver and brain tissues. With respect to the functional and metabolic parameters of the liver, however, the extract provided little or no protection. This includes morphological signs of inflammation and the especially important functional parameter gluconeogenesis, which was impaired by paracetamol. Considering these results and the long list of extracts and substances that are said to have hepatoprotective effects, it would be useful to incorporate evaluations of functional parameters into the experimental protocols of studies aiming to attribute or refute effective hepatoprotective actions to natural products.

Vitamin E (alpha-tocopherol) supplementation in diabetic rats: effects on the proximal colon.

BACKGROUND: Neuropathy is one of the complications caused by diabetes mellitus which is directly related to the gastrointestinal manifestations of the disease. Antioxidant substances, such as vitamin E, may play an important role in the reduction of the neurological damage caused by diabetes mellitus. The aim of the present study was to determine whether vitamin E (alpha-tocopherol) at different concentrations induces any effects on the morphology of the intestinal wall and intrinsic innervation in the proximal colon of diabetic rats. METHODS: Thirty rats (90-day-old) were assigned to the following groups: N (normoglycemic), NE1 (normoglycemic supplemented with vitamin E 0.1%), NE2 (normoglycemic supplemented with vitamin E 2%), D (diabetic), DE1 (diabetic supplemented with vitamin E 0.1%), and DE2 (diabetic supplemented with vitamin E 2%). Animals received vitamin E supplementation for 120 days and were sacrificed when they were 210 days old. The proximal colon of each animal was subjected to histology to study the intestinal wall and goblet cells and processed for whole-mount preparations to morphoquantitatively determine the total myenteric population. RESULTS: Supplementation with vitamin E significantly reduced glycemia and glycated hemoglobin values and preserved the number of myenteric neurons in group DE2, without affecting intestinal area or thickness of the intestinal wall or muscular tunic. CONCLUSION: Vitamin E (2%) influenced the glycemic parameters and had a neuroprotective effect on the total myenteric population, but the morphometric characteristics of the intestinal wall were unaffected.

The number and profile of reactive NADH-d and NADPH-d neurons of myenteric plexus of six-month-old rats are different in the cecum portions / O número de neurônios e a área do perfil neuronal NADH-d e NADPH-d reativos do plexo mioentérico de ratos com seis meses de idade são diferentes nas diferentes porções e regiões do ceco

Whole-mount preparations were prepared and submitted to NADH-diaphorase and NADPH-diaphorase histochemistry techniques. The myenteric plexus arrangement and the number of neurons were comparatively evaluated among the different portions of the cecum. The neurons from the apical and basal regions were distributed in classes at intervals of 100µm², the means of the corresponding intervals being compared. The ganglia, in both techniques, were often connected by fine bundles, which became thicker in the mesenteric region and in the region next to the cecal ampulla. The number of positive NADH-d neurons was higher than that of NADPH-d neurons in all portions, from both regions. The numbers of reactive NADH-d e NADPH-d neurons were significantly different among the different portions of the cecum, except for the antimesenteric basal and intermediate basal regions, considering the NADH-d neurons. The profile area for the reactive NADH-d e NADPH-d neurons was higher in the apical region than in the basal area. Differences in arrangement, distribution and size of positive NADH-d e NADPH-d neurons in the different cecum portions evidenced the importance of the subdivision of the analyzed organ.

Estudaram-se o arranjo do plexo mioentérico, o número de neurônios e a área do perfil do corpo celular (µm²) dos neurônios mioentéricos, nas regiões apical e basal do ceco de ratos Wistar com 6 meses de idade. Estas regiões foram subdivididas nas seguintes porções: apical mesentérica (AM); apical intermediária (AI); apical antimesentérica (AA); próximo à ampola cecal (PA); basal intermediária (BI), e basal antimesentérica (BA). Foram montados preparados de membrana que receberam as técnicas histoquímica de NADH-diaforase (NADH-d) e NADPH-diaforase (NADPH-d). O arranjo do plexo mioentérico e o número de neurônios foram avaliados comparativamente entre as diferentes porções das regiões do ceco. Os neurônios das regiões apical e basal foram distribuídos em classes com intervalos de 100µm², sendo comparadas às médias da mensuração dos pares. Os gânglios, em ambas as técnicas, apresentavam-se, em geral, conectados por feixes delicados, tornando-se mais espessos na porção mesentérica e naquela próxima à ampola cecal. O número de neurônios NADH-d positivos foi maior do que o de NADPH-d em todas as porções, de ambas as regiões. O número de neurônios reativos a NADH-d e NADPH-d foi significativamente diferente entre as diferentes porções do ceco, com exceção das comparações entre as porções basal antimesentérica e basal intermediária, para os primeiros; e entre a basal intermediária e porção próxima à ampola cecal, e comparando-se a apical mesentérica e porção próxima à ampola cecal, para os neurônios NADPH-d positivos. A área do perfil dos neurônios NADH-d e NADPH-d reativos foi maior na região apical do que na basal. Pela primeira vez, o número de neurônios do plexo mioentérico é reportado em porções pré-estabelecidas do ceco de ratos. Nossos resultados reiteram a importância da indicação precisa da porção estudada em pesquisas envolvendo este segmento intestinal.