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ObjectiveThe aim of the study was to evaluate the effects of supplementation with glucosyl hesperidin (GH), with or without physical training, on body weight, fat depot, glucose and plasma lipids, oxidative status and vascular function of rats fed with high-fat diet (HFD).MethodsAfter weaning, male Wistar rats were fed with an HFD plus fructose for 12 weeks and started receiving oral antioxidant supplementation and/or physical training after the fourth week of diet for eight further weeks. Body weight, epididymal and retroperitoneal fat, plasma glucose and lipids, oxidative status and mesenteric artery reactivity were evaluated.ResultsRats fed with HFD presented higher body weight gain and fat accumulation compared to control rats, while GH supplementation did not influence these parameters. Physical training reduced the body weight gain and fat accumulation and modulated the oxidative status by increasing superoxide dismutase activity and total antioxidant capacity and reducing lipid peroxidation. GH alone decreased lipid peroxidation. However, when given to exercised rats, it impaired the response elicited by physical training. HFD caused endothelial dysfunction, and neither GH nor physical exercise prevented it. Potency of sodium nitroprusside was increased in exercised animals but not in GH-supplemented rats.ConclusionPhysical exercise partially decreased the body fat accumulation, decreased plasma levels of glucose and lipids and improved general oxidative status and endothelium-independent relaxation in mesenteric arteries of rats fed with HFD. GH exhibited benefits only in the oxidative status. However, GH given in association with physical exercise did not cause further changes in addition to those promoted by physical exercise. On the contrary, in exercised animals, GH prevented those changes elicited by physical training in plasma glucose and lipids, oxidative status and endothelium-independent relaxation.

Endothelial dysfunction is an early manifestation of atherosclerosis. The cholesteryl ester transfer protein (CETP) has been considered pro-atherogenic by reducing plasma HDL levels. However, CETP may exhibit cell- or tissue-specific effects. We have previously reported that male mice expressing the human CETP gene show impaired endothelium-mediated vascular relaxation associated with oxidative stress. Although sexual dimorphisms on the metabolic role of CETP has been proposed, possible sex differences in the vascular effects of CETP were not previously studied. Thus, here we investigated the endothelial function of female CETP transgenic mice as compared to non-transgenic controls (NTg). Aortas from CETP females presented preserved endothelium-dependent relaxation to acetylcholine and an endothelium-dependent reduction of phenylephrine-induced contraction. eNOS phosphorylation (Ser1177) and calcium-induced NO levels were enhanced, while reactive oxygen species (ROS) production and NOX2 and SOD2 expression were reduced in the CETP female aortas. Furthermore, CETP females exhibited increased aortic relaxation to 17β-estradiol (E2) and upregulation of heat shock protein 90 (HSP90) and caveolin-1, proteins that stabilize estrogen receptor (ER) in the caveolae. Indeed, CETP females showed an increased E2-induced relaxation in a manner sensitive to ERα and HSP90 inhibitors methylpiperidinopyrazole (MPP) and geldanamycin, respectively. MPP also impaired the relaxation response to acetylcholine in CETP but not in NTg females. Altogether, the study indicates that CETP expression ameliorates anti-contractile endothelial effect and relaxation to E2 in females. This was associated with less ROS production, and increased eNOS-NO and E2-ERα pathways. These results highlight the need for considering sex-specific effects of CETP on cardiovascular risk.

BackgroundUrsodeoxycholic acid (UDCA) and its metabolites tauroursodeoxycholic acid (TUDCA) and glycoursodeoxycholic acid (GUDCA) have been the subject of several pharmacological studies. The objective of this study was to develop an innovative method of quantification by HPL-tandem mass spectrometry (LC-MS/MS), with a lower cost and suitable, for application in bioequivalence studies.MethodsThe procedure involved liquid–liquid extraction for quantification of UDCA/GUDCA and precipitation extraction for TUDCA, using deuterated substances as internal standards (ISs) and Phenomenex Luna 250×4.6 mm 5μ C18 100A column. The mobile phase used was acetonitrile/ammonium acetate 30 mM (420: 580 v/v pH 7) for UDCA, acetonitrile/ammonium acetate 10 mM/ammonium hydroxide (400:600: 0.5 v/v/v pH 9) for GUDCA, and acetonitrile/ammonium acetate 10 mM (570: 430 v/v pH 7) for TUDCA. Ions were monitored by the electrospray ion source (ESI) mass spectrometer, operating in a negative ionization mode. Compound determination was performed by LC-MS/MS system using a calibration curve of 15–10,000 ng/mL for UDCA/GUDCA and 5–500 ng/mL for TUDCA. The method was developed and validated according to the Brazilian National Health Surveillance Agency (ANVISA) of Brazil norms harmonized with the main international guidelines as a prerequisite for conducting in vivo study in human volunteers.ResultsThe method did not present matrix effect and residual effect, showing to be selective for studied molecules, with adequate accuracy and precision. In addition, the method was considered sensitive presenting a coefficient of variation less than 20% for the lower limit of quantification of each compound.ConclusionThis method can be applied in bioequivalence studies to determine ursodiol and its metabolites reproducibly, simply, and effectively with the use of readily accessible analytical materials and instrumentation.

Hesperidin has been used to manage venous disease and has been shown to have vasodilator, antiinflammatory and antioxidant properties. The aim of this work was to evaluate the efects of acute treatment with hesperidin (HD) on the vascular reactivity of rats in the onset of arterial hypertension induced by L-NAME. Male Wistar rats were divided into 3 groups as follow: 1- Control (CTL); 2- L-NAME (LN); 3- L-NAME + Hesperidin (LNHD). LN was given by gavage at the dose of 75mg/Kg, concomitantly with HD at the dose of 0.5 mmol/Kg, 24 hours previously to the sacrifice. After sacrifice, the blood was collected and the aorta removed and mounted in a wire myograph to assess concentration response curves to acetylcholine (ACh) and sodium nitroprusside (SNP). ACh elicited concentration dependent relaxation in aorta of CTL rats, reaching a maximum relaxation of 89 ± 3%, which was significantly reduced in LN group (37 ± 7%). Treatment with HD partially prevented this decrease, reaching the maximum relaxation of 72 ± 2%. On the other hand, SNP induced relaxation was more potent on the aorta of LN (pEC 50 9.67 ± 0.11) when compared to CTL (pEC 50 8.51 ± 0.13) and LNHD rats (pEC 50 8.90 ± 0.09). The oxidative status was not changed by any treatment since SOD activity was 11 ± 1, 9 ± 2 and 12 ± 0.5 U/mL, for CTL, LN and LNHD, respectively and lipid peroxidation measured by TBARS assay showed a MDA concentration of 29 ± 8, 35 ± 7 and 23 ± 3 μM for CTL, LN and LNHD, respectively. Altogether, these data suggest that that Hesperidin prevents the impairment of endothelium-dependent vascular relaxation, through a mechanism not related to its antioxidant property.