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Unlike non-steroidal anti-inflammatory drugs (NSAIDs), metamizole has poor anti-inflammatory effects; and is suitable for models where analgesia, but not anti-inflammatory effects, is desirable. Like opioids, these drugs produce perioperative analgesia while reducing anaesthetic requirements, but it remains unclear whether they may develop tolerance or hyperalgesia, and thus decrease in analgesic efficacy. The aim was to determine whether tolerance or hyperalgesia to metamizole occurred in rats, and whether the sevoflurane minimum alveolar concentration (MAC) was affected. In a randomized, prospective, controlled study, male Wistar rats (n = 8 per group) were administered metamizole (300 mg/kg, day 4). Previously, the following treatments were provided: daily metamizole for four days (0–3), morphine (10 mg/kg; positive control, day 0 only) or saline (negative control). The main outcome measures were mechanical (MNT) and warm thermal (WNT) nociceptive quantitative sensory thresholds. The baseline sevoflurane MAC and the reduction produced by the treatments were also determined. The mean (SD) baseline MAC [2.4(0.2)%vol] was decreased by morphine and metamizole by 45(11)% and 33(7)% (P = 0.000, both), respectively. Baseline MNT [35.4(4.5) g] and WNT [13.2(2.4) s] were decreased by morphine and metamizole: MNT reduction of 22(6)% (P = 0.000) and 22(7)% (P = 0.001), respectively and WNT reduction of 34(14)% (P = 0.000) and 24(13)% (P = 0.001). The baseline MAC on day 4 was neither modified by treatments nor the MAC reduction produced by metamizole (days 0 and 4; P > 0.05). In conclusion, repeated metamizole administration may produce hyperalgesia, although it may not modify its anaesthetic sparing effect. The clinical relevance of this effect in painful research models requiring prolonged analgesic therapy warrants further investigation. [ABSTRACT FROM AUTHOR]

Over the past few decades, the cardiovascular benefits of a high dietary intake of long-chain polyunsaturated fatty acids (PUFAs), like docosahexaenoic acid (DHA), have been extensively studied. However, many of the molecular mechanisms and effects exerted by PUFAs have yet to be well explained. The lack of sex hormones alters vascular tone, and we have described that a DHA-supplemented diet to orchidectomized rats improve vascular function of the aorta. Based on these data and since the mesenteric artery importantly controls the systemic vascular resistance, the objective of this study was to analyze the effect of a DHA-supplemented diet on the mesenteric vascular function from orchidectomized rats. For this purpose mesenteric artery segments obtained from control, orchidectomized or orchidectomized plus DHA-supplemented diet were utilized to analyze: (1) the release of prostanoids, (2) formation of NO and ROS, (3) the vasodilator response to acetylcholine (ACh), as well as the involvement of prostanoids and NO in this response, and (4) the vasoconstrictor response to electrical field stimulation (EFS), analyzing also the effect of exogenous noradrenaline (NA), and the NO donor, sodium nitroprusside (SNP). The results demonstrate beneficial effects of DHA on the vascular function in orchidectomized rats, which include a decrease in the prostanoids release and superoxide formation that were previously augmented by orchidectomy. Additionally, there was an increase in endothelial NO formation and the response to ACh, in which NO involvement and the participation of vasodilator prostanoids were increased. DHA also reversed the decrease in EFS-induced response caused by orchidectomy. All of these findings suggest beneficial effects of DHA on vascular function by reversing the neurogenic response and the endothelial dysfunction caused by orchidectomy. [ABSTRACT FROM AUTHOR]

Benefits of n-3 polyunsaturated fatty acids (PUFAs) against cardiovascular diseases have been reported. Vascular tone regulation is largely mediated by endothelial factors whose release is modulated by sex hormones. Since the incidence of cardiovascular pathologies has been correlated with decreased levels of sex hormones, the aim of this study was to analyze whether a diet supplemented with the specific PUFA docosahexaenoic acid (DHA) could prevent vascular changes induced by an impaired gonadal function. For this purpose, control and orchidectomized rats were fed with a standard diet supplemented with 5% (w/w) sunflower oil or with 3% (w/w) sunflower oil plus 2% (w/w) DHA. The lipid profile, the blood pressure, the production of prostanoids and nitric oxide (NO), and the redox status of biological samples from control and orchidectomized rats, fed control or DHA-supplemented diet, were analyzed. The vasodilator response and the contribution of NO, prostanoids and hyperpolarizing mechanisms were also studied. The results showed that orchidectomy negatively affected the lipid profile, increased the production of prostanoids and reactive oxygen species (ROS), and decreased NO production and the antioxidant capacity, as well as the participation of hyperpolarizing mechanisms in the vasodilator responses. The DHA-supplemented diet of the orchidectomized rats decreased the release of prostanoids and ROS, while increasing NO production and the antioxidant capacity, and it also improved the lipid profile. Additionally, it restored the participation of hyperpolarizing mechanisms by activating potassium. Since the modifications induced by the DHA-supplemented diet were observed in the orchidectomized, but not in the healthy group, DHA seems to exert cardioprotective effects in physiopathological situations in which vascular dysfunction exists. [ABSTRACT FROM AUTHOR]

Abstract: Docosahexaenoic acid (DHA) supplemented in pharmaceuticals and functional foods is commonly re-esterified as ethyl esters (DHA-EE) or alternatively as triacylglycerol (DHA-rTAG). The aim of this study was to investigate the modulation of plasmatic lipid profiles of two doses of DHA-EE and DHA-rTAG. During 8weeks, Wistar rats were supplemented with high and low doses of DHA-EE and DHA-rTAG integrated in a hypercholesterolemic diet. DHA supplementation reduced total weight gain, adiposity index, HDL-cholesterol and glucose plasmatic concentration associated to the dose administered. T-CHO and TAG seem to be reduced more efficiently by high doses of DHA-rTAG, while adipose tissue distribution and reduction of FFA are improved with DHA supplementation, regardless of the dose and form of supplementation. Therefore, metabolic effects of DHA supplementation may be determined not only by the dosage administered, but also by the ester form in which this molecule is presented. [Copyright &y& Elsevier]

Background: Mannoproteins are yeast cell wall componend, and rich in mannose. The use of foods rich in mannose as carbohydrate, could have a bioprotective effect against entrobacteria intestinal infection. Nothing is known about mannoproteins' activity in inflammatory bowel processes induced by entrobacteria. This study investigates the effects of mannoprotein administration via a liquid diet on inflammatory response and TLR5 expression during intestinal tissue injury in a rat model of infection with Salmonella typhimurium. Methods: Adult Wistar male rats were divided into three groups: control, and mannoprotein E1 at 10 or 15%. Animals were fed with a liquid diet supplemented or not with mannoprotein E1. Groups were infected by intragastrical administration of S. typhimurium. 24 h post-inoculation samples of spleen, ileum and liver were collected for microbiological studies. Gut samples were processed to determine levels of proinflammatory cytokines (mRNA) and TLR5 (mRNA and protein) by quantitative PCR and Western-blot, and the number of proliferative and apoptotic cells determined by immunohistochemistry. Results: Ininfected levels of proinflammatory cytokines and TLR5 were higher in untreated controls than in the animals receiving mannoprotein. Proliferation was similar in both groups, whereas apoptosis was higher in controls. Curiosly, the mannoprotein effect was dose dependent. Conclusions: Mannoprotein administration in a liquid diet seems to protect intestinal tissue against S. typhimurium infection. This protection seems to expressed as a lower pro-inflammatory response and TLR5 downregulation in gut epithelium, as well as by an inhibition of apoptosis. Nevertheless, the molecular mechanism by which mannoprotein is able to regulate these responses remain unclear. These results could open up new avenues in the use of mannoproteins as prebiotics in the therapeutic strategy for treatment of inflammatory gut processes induced by microbia. [ABSTRACT FROM AUTHOR]

Experimental small bowel transplantation (SBT) in rats has been proven to be a useful tool for the study of ischemia-reperfusion and immunological aspects related to solid organ transplantation. However, the model is not completely refined, specialized literature is scarce and complex technical details are typically omitted or confusing. Most studies related to acute rejection (AR) use the orthotopic standard, with small sample sizes due to its high mortality, whereas those studying chronic rejection (CR) use the heterotopic standard, which allows longer term survival but does not exactly reflect the human clinical scenario. Various animal strains have been used, and the type of rejection and the timing of its analysis differ among authors. The double purpose of this study was to develop an improved unusual AR model of SBT using the heterotopic technique, and to elaborate a guide useful to implement experimental models for studying AR. We analyzed the model's technical details and expected difficulties in overcoming the learning curve for such a complex microsurgical model, identifying the potential problem areas and providing a step-by-step protocol and reference guide for future surgeons interested in the topic. We also discuss the historic and more recent options in the literature. [ABSTRACT FROM AUTHOR]

Highlights: [•] An ingredient rich in fructans and insoluble dietary fibre (ADF) is developed. [•] Effects of consuming ADF or/with Jamaica calyces (ADF–JC) is evaluated in rats. [•] ADF and ADF–JC reduces body weight gain in hypercholesterolemic (HC) rats. [•] ADF and ADF–JC reduces expression of ABCGs and NCP-1 intestinal transporters in HC rats. [•] ADF and ADF–JC improves redox status in HC rats. [Copyright &y& Elsevier]