Vasorelaxant and antihypertensive effects of methanolic extracts from Hymenocardia acida Tul.

Ethnopharmacological Relevance: In Congolese traditional medicine, decoctions of Hymenocardia acida root bark (HaRB) and trunk bark (HaTrB) are used for the treatment of conditions assumed to be hypertension. In this work, we propose to study the vasorelaxant effect of HaRB and HaTrB methanolic extracts on isolated rat thoracic aorta, to characterize the group of molecules responsible for the observed vasorelaxant activity, to evaluate the in vitro antioxidant activity of these extracts and to determine the antihypertensive activity of the HaRB extract on spontaneously hypertensive rats (SHR).

Materials And Methods: The vasorelaxant effect of the HaRB and HaTrB methanolic extracts was studied on endothelium-intact aortic rings pre-contracted with phenylephrine (PE, 1μM).

Vascular oxidative stress induced by diesel exhaust microparticles: synergism with hypertension.

Background: Epidemiological and clinical studies have shown that traffic-related air pollution and, particularly, diesel exhaust particles (DEP) are strongly linked to cardiovascular mortality.

Methods: Vascular toxicity was studied by assessing vasomotor responses of aortas isolated from normotensive Wistar rats exposed in vitro to DEP (DEP suspension and aqueous DEP extract). In vivo experiments were performed on Wistar rats and spontaneously hypertensive rats (SHRs) exposed for 4 weeks via intratracheal instillation to either DEP or saline vehicle.

Vascular effects and antioxidant activity of two Combretum species from Democratic Republic of Congo.

Ethnopharmacological Relevance: Combretum racemosum P. Beauv (Combretaceae) leaves (CrLv) and root bark (CrRB) and Combretum celastroides subsp. laxiflorum Welw (Combretaceae) leaves (ClLv) are used in Congolese traditional medicine for several therapeutic purposes, notably for the treatment of conditions consistent with hypertension.

Oxidative stress produced by circulating microparticles in on-pump but not in off-pump coronary surgery.

Objective: This study was undertaken to assess whether plasmas isolated during off-pump coronary surgery trigger less oxidative stress than those isolated during on-pump surgery.

Methods And Results: Plasmas were sampled from patients before (TO), just after (TI) and 24 hours after (T2) cardiac surgery (n=24 on-pump and n=10 off-pump). Rings of rat thoracic aortas were incubated for 20 hours with these different plasmas (100 microl + 4 ml medium) or saline (control).

Protection of aortic endothelial function in both normal and diabetic rats by intravenous bolus injection of a medium-chain triglyceride: fish oil emulsion.

The bolus intravenous injection of a novel medium-chain triglyceride:fish oil emulsion (MCT:FO) was recently proposed as a tool to provoke a rapid and sustained increase of cell phospholipid content in long-chain polyunsaturated omega3 fatty acids, for instance in selected subjects prior to anesthesia and surgery. In this study, therefore, the possible protective effect of MCT:FO upon aortic endothelial function was investigated in both normal and diabetic rats. The animals were injected intravenously 20 h before sacrifice with 1.

Homoisoflavanones from Disporopsis aspera.

From cytotoxic extracts of the roots of Disporopsis aspera Engl. (Liliaceae) a homoisoflavanone, disporopsin (3-(2',4'-dihydroxy-benzyl)-5,7-dihydroxy-chroman-4-one) (1) and three rare methyl-homoisoflavanones, 3-(4'-hydroxy-benzyl)-5,7-dihydroxy-6-methyl-chroman-4-one (2), 3-(4'-hydroxy-benzyl)-5,7-dihydroxy-6,8-dimethyl-chroman-4-one (3) and 3-(4'-hydroxy-benzyl)-5,7-dihydroxy-6-methyl-8-methoxy-chroman-4- one (4) along with five other known compounds, N-trans-feruloyl tyramine (5), adenine (6), 5-(hydroxymethyl)-2-furfural (7), beta-sitosterol (8) and beta-sitosteryl glucopyranoside (9) were isolated. The structures of compounds 1-2 were elucidated by spectral data (1, 2-D NMR and EIMS).

Ramipril treatment protects against nitrate-induced oxidative stress in eNOS-/- mice: An implication of the NADPH oxidase pathway.

The development of nitrate tolerance has been found to be associated with vascular production of superoxide anion (O2-*), generated mainly by the eNOS and NADPH oxidase pathways. The aim of our study was to investigate whether long-term angiotensin-converting enzyme inhibition by ramipril is able to protect against nitrate tolerance in the aortas of eNOS-deficient (eNOS-/-) mice and to assess the implication of the NADPH oxidase pathway. Therefore, 3 types of treatment were given to wild-type (WT) and eNOS-/- mice: group 1 received ramipril for 5 weeks and a co-treatment with ramirpil plus nitroglycerine (NTG) during the last 4 days, group 2 received only NTG, and group 3 served as control.

Rosuvastatin treatment protects against nitrate-induced oxidative stress in eNOS knockout mice: implication of the NAD(P)H oxidase pathway.

Nitrate tolerance is associated with an enhanced superoxide anion (O(2)(-)) production and may be attenuated by statins as they interact with the two main endothelial NO synthase (eNOS) and NAD(P)H oxidase pathways involved in this oxidative stress. Groups of wild-type (wt, C57Bl/6J) and eNOS knock-out mice (eNOS(-/-)) received rosuvastatin (20 mg kg(-1) day(-1) p.o.

Sustained enrichment of liver phospholipids and triglycerides in eicosapentaenoate after a bolus intravenous injection of a medium-chain triglycerides:fish oil emulsion to streptozotocin (Type 1) and Goto-Kakizaki (Type 2) diabetic rats.

This study deals with the sustained enrichment of liver phospholipids and triglycerides in long-chain polyunsaturated omega3 fatty acids (omega3) found after the bolus intravenous injection of a novel medium-chain triglyceride:fish oil emulsion (MCT:FO) to streptozotocin (Type 1) and Goto-Kakizaki (Type 2) diabetic rats. Twenty hours after injection of the MCT:FO emulsion, the relative concentration of omega3 was indeed higher in liver phospholipids and triglycerides than that found in rats injected with either saline or a control medium-chain triglyceride:long-chain triglyceride emulsion. This coincided with a decrease in the ponderal percentage of C18:3omega3, C20:4omega6 and/or C22:4omega6 in liver triglycerides.

Rosuvastatin treatment protects against nitrate-induced oxidative stress.

Nitrate tolerance is associated with an enhanced superoxide anion production and can be attenuated by statins, which interact with the 2 main [eNOS and NAD(P)H oxidase] pathways involved in producing this oxidative stress. Three groups of normocholesterolemic rats were treated: group 1 received rosuvastatin (10 mg/kg/d PO) for 5 weeks and in the last 3 days cotreatment with nitroglycerin (NTG 50 mg/kg/d, subcutaneous injections BID); group 2 received only NTG (50 mg/kg/d BID for the last 3 days); and group 3 served as control. Rings of thoracic aortas from these groups were studied in organ baths.

Preparation of poly(N-isopropylacrylamide) copolymers and preliminary assessment of their acute and subacute toxicity in mice.

A subacute toxicity study was conducted to evaluate the oral toxicity profile of poly(N-isopropylacrylamide) (PNIPAAm) derivatives. These thermoresponsive polymers may have several potential pharmaceutical applications such as ingredient for oral solid dosage form. A preliminary acute oral toxicity study was performed with one of the polymer (PNIPAAm-co-NVA) at a unique dose of 4000 mg/kg body weight administered to six male and six female mice, to determine the dosage for further evaluation.

A sugar ester and an iridoid glycoside from Scrophularia ningpoensis.

From cytotoxic extracts of the roots of Scrophularia ningpoensis Hemsl. (Scrophulariaceae) a new sugar ester, ningposide D (3-O-acetyl-2-O-p-methoxycinnamoyl-alpha(beta)-L-rhamnopyranose) (1) and a new iridoid glycoside, scrophuloside B4 (6-O-(2''-O-acetyl-3''-O-cinnamoyl-4''-O-p-methoxycinnamoyl-alpha-L-rhamnopyranosyl) catalpol) (2) along with known compounds: oleanonic acid (3), ursolonic acid (4), cinnamic acid (5), 3-hydroxy-4-methoxy benzoic acid (6), 5-(hydroxymethyl)-2-furfural (7) and beta-sitosterol (8) were isolated. The structures of the new compounds were elucidated by spectral data (1, 2D NMR, EI, HRESI-MS and MS/MS).

Prevention of nitrate tolerance by long-term treatment with statins.

Unlabelled: Recent studies have shown that statins seem to upregulate the endothelial NO synthase pathway (eNOS) and may, therefore, enhance NO availability, a direct scavenger of O2- and an inhibitor of oxidative enzymes.

Methods: To assess whether the oxidative stress produced by an in vivo exposure to nitroglycerin (NTG) is attenuated by statins, 4 groups of normocholesterolemic rats were treated; group 1 received pravastatin (20 mg/kg/d p.o) and group 2 atorvastatin (10 mg/kg/d) both for 5 weeks and the last 3 days, a cotreatment with the statin plus NTG (50 mg/kg/d, s.

Chronic hydroxymethylglutaryl coenzyme a reductase inhibition and endothelial function of the normocholesterolemic rat: comparison with angiotensin-converting enzyme inhibition.

Hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitors seem to have clinical benefits beyond those predicted by their lipid-lowering action. The objective was to evaluate the vascular effect of long-term treatment with statins on isolated rat aorta and their ability to prevent the acute toxicity of oxidized low-density lipoproteins (oxLDLs) compared with angiotensin-converting enzyme (ACE) inhibitors. Four groups of Wistar rats were treated for 5 weeks.