Microbiota-sensitive drug delivery systems based on natural polysaccharides for colon targeting.

Colon targeting is an ongoing challenge, particularly for the oral administration of biological drugs or local treatment of inflammatory bowel disease (IBD). In both cases, drugs are known to be sensitive to the harsh conditions of the upper gastrointestinal tract (GIT) and, thus, must be protected. Here, we provide an overview of recently developed colonic site-specific drug delivery systems based on microbiota sensitivity of natural polysaccharides. Polysaccharides act as a substrate for enzymes secreted by the microbiota located in the distal part of GIT. The dosage form is adapted to the pathophysiology of the patient and, thus, a combination of bacteria-sensitive and time-controlled release or pH-dependent systems can be used for delivery.

Removal Efficiency of Insoluble ß-Cyclodextrin Polymer from Water-Soluble Carcinogenic Direct Azo Dyes.

A batch system was applied to study the adsorption of three dyes (methyl violet, eriochrom black T and helianthin) from aqueous solution onto ß-cyclodextrin polymer, synthesized by using citric acid as a cross linking agent. This polymer lets to adsorb only methyl violet for this effect, several operator variables was checked only with this kind of dye, the removal efficiently increases with increase in adsorbent amount; elevation of temperature lets also to improve the dye adsorption; ionic strength has not effect on dye adsorption process, for the pH we have remarked a slight decrease in removal efficiently with increasing of pH values. Equilibrium study was investigated by applying three models (Langumir, Frendlich and Temkin), results show that Langumir isotherm is the appropriate model. FTIR spectra show the complex inclusion formation which dominates the adsorption mechanism, confirmed by the absence of characteristic peaks of methyl violet in ß-cyclodextrin after adsorption.

Effect of Autoclaving on the Physicochemical Properties and Biological Activity of Aluminum Oxyhydroxide Used as an Adjuvant in Vaccines.

The long-term biodistribution of non-biodegradable microstructures or nanostructures used in vaccinations is widely unknown. This is the case for aluminum oxyhydroxide, the most widely used vaccine adjuvant, which is a nanocrystalline compound that spontaneously forms nanoprecipitates. Although generally well-tolerated, aluminum oxyhydroxide is detected in macrophages a long time after vaccination in individuals predisposed to the development of systemic and neurological aspects of the autoimmune (inflammatory) syndrome induced by modified adjuvant. In the present study, we established that the terminal sterilization of aluminum oxyhydroxide by autoclaving in final container vials produced measurable changes in its physicochemical properties. Moreover, we found that these changes included (1) a decreasing in the pH of aluminum oxyhydroxide solutions, (2) a reduction in the adsorption capacity of bovine serum albumin, (3) a shift in the angle of X-ray diffraction, (4) a reduction in the lattice spacing, causing the crystallization and biopersistence of modified aluminum oxyhydroxide in the macrophage, as well as in muscle and the brain.

The effect of camelina oil on vascular function in essential hypertensive patients with metabolic syndrome: a randomized, placebo-controlled, double-blind study.

BACKGROUND: The effects of a dietary supplementation with the vegetable ω-3 α-linolenic acid (ALA) on cardiovascular homeostasis are unclear. In this context, it would be interesting to assess the effects of camelina oil. OBJECTIVE: This study aimed to assess the cardiovascular and metabolic effects of camelina oil in hypertensive patients with metabolic syndrome. METHODS: In a double-blind, placebo-controlled randomized study, treated essential hypertensive patients with metabolic syndrome received, during 6 mo, either cyclodextrin-complexed camelina oil containing ≈ 1.5 g ALA/d (n = 40) or an isocaloric placebo (n = 41), consisting of the same quantity of cyclodextrins and wheat starch. Anthropometric data, plasma lipids, glycemia, insulinemia, creatininemia, TBARs, high-sensitivity C-reactive protein, and n-3, n-6, and n-9 fatty acids in erythrocyte membranes were measured. Peripheral and central blood pressures, arterial stiffness, carotid intima-media thickness, and brachial artery endothelium-dependent flow-mediated dilatation (FMD) and endothelium-independent dilatation were assessed. RESULTS: Compared with placebo, camelina oil increased ALA (mean ± SD: 0 ± 0.04 compared with 0.08 ± 0.06%, P <0.001), its elongation product EPA (0 ± 0.5 compared with 0.16 ± 0.65%, P <0.05), and the n-9 gondoic acid (GA; 0 ± 0.04 compared with 0.08 ± 0.04%, P <0.001). No between-group difference was observed for cardiovascular parameters. However, changes in FMD were associated with the magnitude of changes in EPA (r = 0.26, P = 0.03). Compared with placebo, camelina oil increased fasting glycemia (-0.2 ± 0.6 compared with 0.3 ± 0.5 mmol/L, P <0.001) and HOMA-IR index (-0.8 ± 2.5 compared with 0.5 ± 0.9, P <0.01), without affecting plasma lipids, or inflammatory and oxidative stress markers. Changes in HOMA-IR index were correlated with the magnitude of changes in GA (r = 0.32, P <0.01). Nutritional intake remained similar between groups. CONCLUSION: ALA supplementation with camelina oil did not improve vascular function but adversely affected glucose metabolism in hypertensive patients with metabolic syndrome. Whether this adverse effect on insulin sensitivity is related to GA enrichment, remains to be elucidated.

The Use of Cyclodextrin or its Complexes as a Potential Treatment Against the 2019 Novel Coronavirus: A Mini-Review.

Severe Acute Respiratory Syndrome Coronavirus 2 has spread rapidly since its discovery in December 2019 in the Chinese province of Hubei, reaching this day all the continents. This scourge is, unfortunately, in lineage with various dangerous outbreaks such as Ebola, Cholera, Spanish flu, American seasonal flu. Until today, the best solution for the moment remains prevention (Social distancing, hand disinfection, use of masks, partial or total sanitary containment, etc.); there is also the emergence of drug treatment (research and development, clinical trials, use on patients). Recent reviews emphasized the role of membrane lipids in the infectivity mechanism of SARS-COV-2. Cholesterol-rich parts of cell membranes serve as docking places of host cells for the viruses. Coronavirus 2 is a member of a virus family with lipid envelope that fuses with host cell through endocytosis, internalizing its components in the cell. In vitro cell models have shown that depletion of cholesterol by cyclodextrin, and particularly methyl beta cyclodextrin disturb the host cell membrane lipid composition this way, reducing the attachment of the virus to the protein receptors. This review aims to summarize the state of the art of research concerning the use of cyclodextrin or its complexes as a potential treatment against this new virus and update work already published.

New Formulation and Evaluation of Camptothecin Encapsulated and/or Dispersed Suppository.

BACKGROUND: Camptothecin is known for its potent anticancer activity. However, its optimal activity is reduced due to its low solubility and stability in biological media. OBJECTIVE: The aim of the present study is to design and characterize a Camptothecin (CPT) suppository formulation. METHODS: Rectal suppositories of camptothecin alone, encapsulated with Cyclodextrin (CD) and in the ternary system (CPT encapsulated with cyclodextrin and dispersed in Polyethylene Glycol (PEG) 6000) were prepared using various hydrophobic and hydrophilic polymeric bases as semi-synthetic glyceride (Suppocire® AM Pellets) and Polyethylene Glycols (PEGs) mixtures. Formulations were evaluated by various parameters like weight variation, drug content, hardness and liquefaction time. In vitro release study was performed in USP type I apparatus using phosphate buffer pH 7.2 as dissolution media. RESULTS: Suppositories were within the permissible range of all physical parameters. In vitro drug released from water soluble base (PEG) was greater than that from oil soluble base with ninety percent (90%) of drug dissolution. It was also established that drug release from various formulations was by diffusion mechanism, according to the Higuchi's equation. CONCLUSION: This new formulation offers a new approach to colorectal cancer treatment by offering an alternative and simple drug administration route.

Development and validation of HPLC method for simultaneous quantification of alpha-tocopherol (free or encapsulated) and cholesterol in semen cryopreservation media.

The HPLC method was developed and validated for assaying alpha-tocopherol and cholesterol in cryopreservation media. Chromatographic separation was performed on an isocratic system, using a C-18 column. The mobile phase was composed of a mixture of methanol:acetonitrile:water 68:28:4 (v/v/v), using a flow rate of 1.5 mL/min and 20 µL injection volume, at a wavelength of 208 nm. The method was validated according to International Conference on Harmonization guidelines. The method proved to be specific, accurate, precise, and linear with correlation coefficients greater than 0.996 over a wide concentration range of both analytes. Vitamin E and cholesterol presented limits of detection of 0.002 mg/mL, 0.026 mg/mL and limits of quantitation of 0.006 mg/mL, 0.086 mg/mL, respectively. This method is simple and rapid, shows high precision and accuracy, and offers the advantage of simultaneous assaying of vitamin E and cholesterol (alone, in cyclodextrins complexes or in liposome loaded) on semen cryopreservation media.

Syndromic Surveillance of Acute Gastroenteritis Using the French Health Insurance Database: Discriminatory Algorithm and Drug Prescription Practices Evaluations.

The French national public health agency (Santé publique France) has used data from the national health insurance reimbursement system (SNDS) to identify medicalised acute gastroenteritis (mAGE) for more than 10 years. This paper presents the method developed to evaluate this system: performance and characteristics of the discriminatory algorithm, portability in mainland and overseas French departments, and verification of the mAGE database updating process. Pharmacy surveys with certified mAGE from 2012 to 2015 were used to characterise mAGE and to estimate the sensitivity and predictive positive value (PPV) of the algorithm. Prescription characteristics from these pharmacy surveys and from 2014 SNDS prescriptions in six mainland and overseas departments were compared. The sensitivity (0.90) and PPV (0.82) did not vary according to the age of the population or year. Prescription characteristics were similar within all studied departments. This confirms that the algorithm can be used in all French departments, for both paediatric and adult populations, with stability and durability over time. The algorithm can identify mAGE cases at a municipal level. The validated system has been implemented in a national waterborne disease outbreaks surveillance system since 2019 with the aim of improving the prevention of infectious disease risk attributable to localised tap water systems.

Impact of the acute local inhibition of soluble epoxide hydrolase on diabetic skin microcirculatory dysfunction.

The impact of the local inhibition of soluble epoxide hydrolase, which metabolizes vasodilator and anti-inflammatory epoxyeicosanoids, on diabetic skin microvascular dysfunction was assessed. In diabetic db/db mice, basal skin blood flow assessed using laser Doppler imaging was similar to that of control mice, but thermal hyperemia was markedly reduced. At 2 h after the topical administration of an aqueous gel containing the soluble epoxide hydrolase inhibitor trans-4-[4-(3-adamantan-1-yl-ureido)-cyclohexyloxy]-benzoic acid (t-AUCB: 400 mg/L), the peak concentration of t-AUCB was detected in the skin of diabetic mice, which quickly decreased thereafter. In parallel, 2 h after application of t-AUCB treatment, thermal hyperemia was increased compared to the control gel. Quantification of t-AUCB in plasma of treated animals showed no or low systemic diffusion. Furthermore, haematoxylin and eosin histological staining of skin biopsies showed that skin integrity was preserved in t-AUCB-treated mice. Finally, for pig ear skin, a surrogate for human skin, using Franz diffusion cells, we observed a continuous diffusion of t-AUCB from 2 h after application to beyond 24 h. A single topical administration of a soluble epoxide hydrolase inhibitor improves microcirculatory function in the skin of db/db mice and might represent a new therapeutic approach for preventing the development of skin complications in diabetic patients.

New Polymer Inclusion Membrane Containing ß-Cyclodextrin Polymer: Application for Pharmaceutical Pollutant Removal from Waste Water.

We present herein the preparation of novel polymer inclusion membranes (PIMs) containing insoluble ß-CD polymer as a carrier, polyvinyl chloride as a base polymer, and dibuthylphtalate (DBP) as a plasticizer in varying proportions. The prepared PIMs can be obtained by a simple, fast, and high-yield preparation process. Physicochemical characterizations of such membranes occurred in a homogeneous structure. In addition, Fourier-transform infrared Spectroscopy (FT-IR) analysis found that DBP was inserted between these polymeric chains by non-covalent interactions. This led to a spacing of PVC/poly(ß-cyclodextrin) chains inducing a better access of guest molecules to PIM cyclodextrins. To achieve the elimination of ibuprofen and progesterone, two examples of emerging environmental contaminants that can lead to possible alterations to aquatic environments and affect human health, the effect of three operating parameters was studied (pH, the proportion of ß-cyclodextrin polymer, and wastewater agitation). The proportion of ß-cyclodextrin polymer and wastewater agitation had a favorable influence on drug extraction at 10 ppm. The PIMs containing ß-cyclodextrin polymer was unstable in basic conditions and was more effective at acidic pH. These initial results demonstrate the high potential for drug extraction of this polymer.

Enhanced Dissolution and Oral Bioavailability of Cyclosporine A: Microspheres Based on αß-Cyclodextrins Polymers.

Cyclosporine (CsA) has a selective property of suppressing various T-lymphocyte functions. This is of utmost importance in preventing allograft rejection by several organ transplantations, as well as in the treatment of systemic and local autoimmune disorders. However, the poor water solubility of CsA can be a major hurdle for its absorption into the blood stream, which leads to low bioavailability and thus less efficacy. The aim of this study was to prepare, characterize, and evaluate in vitro as well as in vivo, the potential of the innovative CsA drug delivery system. The latter contains CsA in spherical amorphous solid dispersion (SASD) which is embedded in an original α-cyclodextrin and ß-cyclodextrin polymer mixture (Poly-αß-CD) as a multifunctional amorphous carrier. The new developed SASD formulation showed that CsA was molecularly dispersed in αß-cyclodextrins in an amorphous form, as was confirmed by physicochemical characterization studies. Interestingly, the peptide secondary structure, and thus, the drug activity was not impacted by the preparation of SASD as was shown by circular dichroism. Furthermore, the in vitro CsA release profile kinetics was almost identical to the commercially available product Neoral®. This study presents the first in vivo proof-of-concept for a novel drug delivery system based on Poly-αß-CD containing CsA, with SASD allowing for increased bioavailibility. The pharmacokinetic parameters of cyclosporine A from the spherical spray-dried dispersion formulation was demonstrated in a "rat" animal model. For comparison, the commercially available Neoral® was studied. Importantly, the pharmacokinetic parameters were improved by extending Tmax from 2 to 3 h after the oral administration in rats, and eventually preventing the enterohepatic circulation. All these results clearly demonstrate the improved pharmacokinetic parameters and enhanced bioavailability of CsA in the new developed drug delivery system. These data demonstrated the superiority of the newly developed Poly-αß-CD formulation for oral administration of the poorly soluble CsA in vivo without altering its secondary structure. Poly-αß-CD can be a very useful tool for the oral administration of poorly water-soluble drugs.

Preparation and Characterization of Spherical Amorphous Solid Dispersion with Amphotericin B.

In the present study, new polymer microspheres of amphotericin B (AmB) were prepared by a spray drying technique using cyclodextrin polymers (Poly-CD) to improve the solubility and dissolution of AmB, to prevent in vivo toxic AmB aggregations. Formulations were characterized through scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermal analysis, Raman spectroscopy, particle size, drug purity test and in vitro release studies. The analysis indicated that the chemical structure of AmB remained unchanged in the amorphous solid dispersion, but the structure was changed from crystalline to amorphous. AmB was completely release from such optimized formulations in dissolution media in 40 min. This work may contribute to a new generation of spherical amorphous solid dispersion using a cyclodextrin polymer, which has implications for the possibility of drug development for oral utilization or as powder aerosols for pulmonary administration.

Solid Dispersions for Oral Administration: An Overview of the Methods for their Preparation.

Oral drug delivery remains the most physiological and therefore the most preferred, simplest and easiest administration route. Nevertheless, a multitude of potentially clinically important drugs will not reach the market or achieve their full potential unless their oral bioavailability is improved by formulation. The aim of this review is to present an overview of properties, formulation, excipients and characterization of solid dispersions corresponding to one of the different formulation strategies for design and development of poorly soluble drugs. This work will review and compare in detail the evolution of solid dispersions focused on the different methods of formulation and production of solid dispersions, their stability, their release properties, their pharmacokinetics and methods for their physicochemical characterization.

Pharmacokinetic study of metopimazine by oral route in children.

Metopimazine (MPZ) is an antiemetic considered as a currently used drug. In France, it has become the leading antiemetic mediator due to its good tolerance, however, its pharmacokinetics has never previously been studied in children. MPZ was administered by oral route to 8 children with a single dose of 0.33 mg/kg during an endocrine exploration using stimuli well known for its adverse emetic effects. We used biological remnants from sera following an hGH test in order to obtain the MPZ pharmacokinetics. Plasmatic concentrations of MPZ and the active acid metabolite AMPZ, were quantified by HPLC-MS/MS during a 270 min test period. MPZ is quickly absorbed with a median C max of 17.2 ng/mL at one hour and its half-life is 2.18 h. The plasmatic concentrations of AMPZ were higher than MPZ with a median C max of 76.3 ng/mL, a T max to 150 min and its concentration was approximately maintained at 50 ng/mL from 1 to 4 h. The plasmatic concentrations in children are similar to those observed in adults. No adverse effects, nausea or vomiting occurred during the trial. Therefore, these results confirm the MPZ dosage that should be used in children under 15 kg administered as 0.33 mg/kg up to 3 times a day.

Amorphous solid dispersion studies of camptothecin-cyclodextrin inclusion complexes in PEG 6000.

Abstract: The present work focused on the solubility enhancement of the poorly water-soluble anti-cancer agent camptothecin which, in its natural state, presents poor solubility inducing lack of activity with a marked toxicity. A new approach is adopted by using a ternary system including camptothecin (CPT) and cyclodextrins (CDs) dispersed in polyethylene glycol (PEG) 6000. Camptothecin solubility variations in the presence of α-CD, ß-CD, γ-CD, hydroxypropyl-α-CD (HPα-CD), hydroxypropyl-ß-CD (HPß-CD), permethyl-ß-CD (PMß-CD) and sulfobutyl ether-ß-CD (SBEß-CD), were evaluated by Higuchi solubility experiments. In the second part, the most efficient camptothecin/P-CDs binary systems, mainly HPß-CD and PMß-CD, were dispersed in PEG 6000. In addition to a drug release and modeling evaluation, the CPT interactions with CDs and PEG 6000 to prepared the amorphous solid dispersion in the binary and ternary systems were investigated by Fourier transformed infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analyses (TGA) and X-ray powder diffraction (XRPD). The results showed that HPß-CD and PMß-CD were the most efficient for camptothecin solubilization with highest apparent equilibrium constants. Dissolution studies showed that percentage of CPT alone after two hour in 0.1 M HCI medium, did not exceed 16%, whereas under the same conditions, CPT/PMß-CD complex reached 76%. When dispersing the binary systems CPT/ß-CDs in PEG 6000, the velocity and the percentage of CPT release were considerably improved whatever the CD used, reaching the same value of 85%. The binary and ternary systems characterization demonstrated that CPT inclused into the CDs cavity, replacing the water molecules. Furthermore, a drug transition from crystalline to amorphous form was obtained when solid dispersion is realized. The present work demonstrated that ternary complexes are promising systems for CPT encapsulation, and offer opportunities to use non toxic and commonly solubilizing carriers: ßCD and PEG 6000 to improve bioavailability.

Development and characterization of oral liposomes of vegetal ceramide based amphotericin B having enhanced dry solubility and solubility.

Despite the development of new antifungal, amphotericin B remains one of the most effective agents in the treatment of systemic fungal infections. Many patients exhibit nevertheless intolerance to amphotericin B at higher dosages and parenteral formulations present unlike per os ones, associated risks and high care cost. Free amphotericin B per os showed however an apparently poor absorption. In this study, we evaluate the potential of amphotericin B liposomes formulated with vegetal ceramides for oral administration. Ceramides, one of the constituents of cellular cytoplasmic membranes, constitute an important element in the construction and stability of their lipid bilayer. To fulfill this objective, vegetal ceramides, composed essentially of glucosylceramides, were firstly incorporated in various liposome preparations, entrapping or not amphotericin B, in comparison with phosphatidylcholine liposomes. Then, these preparations were introduced in an "Artificial-Stomach-Duodenum" model to improve their stability for oral administration. The formulation of amphotericin B liposomes containing ceramides presented a mean hydrodynamic size of about 200nm. We showed also that cholesterol and phospholipids are required to prevent drug leakage and to obtain lamellar structure respectively. In "Artificial-Stomach-Duodenum" model, ceramides conferred to liposomes better membrane stability. In addition, ceramides did not alter their drug encapsulation yield being by 75%. This could be explained by the fact that ceramides as we proved, limited the detergent effect of bile salts on liposome membranes.

Interaction Study of an Amorphous Solid Dispersion of Cyclosporin A in Poly-Alpha-Cyclodextrin with Model Membranes by (1)H-, (2)H-, (31)P-NMR and Electron Spin Resonance.

The properties of an amorphous solid dispersion of cyclosporine A (ASD) prepared with the copolymer alpha cyclodextrin (POLYA) and cyclosporine A (CYSP) were investigated by (1)H-NMR in solution and its membrane interactions were studied by (1)H-NMR in small unilamellar vesicles and by (31)P (2)H NMR in phospholipidic dispersions of DMPC (dimyristoylphosphatidylcholine) in comparison with those of POLYA and CYSP alone. (1)H-NMR chemical shift variations showed that CYSP really interacts with POLYA, with possible adduct formation, dispersion in the solid matrix of the POLYA, and also complex formation. A coarse approach to the latter mechanism was tested using the continuous variations method, indicating an apparent 1 : 1 stoichiometry. Calculations gave an apparent association constant of log Ka = 4.5. A study of the interactions with phospholipidic dispersions of DMPC showed that only limited interactions occurred at the polar head group level ((31)P). Conversely, by comparison with the expected chain rigidification induced by CYSP, POLYA induced an increase in the fluidity of the layer while ASD formation led to these effects almost being overcome at 298 K. At higher temperature, while the effect of CYSP seems to vanish, a resulting global increase in chain fluidity was found in the presence of ASD.

Identification of tiagabine degradation products using liquid chromatography with electrospray ionization multistage mass spectrometry and ultra-performance liquid chromatography/high-resolution mass spectrometry.

RATIONALE: Tiagabine hydrochloride monohydrate drug substance (TGB) is an antiepileptic agent effective in the treatment of seizure disorders. The stability of TGB was studied and its degradation products were identified for the first time. METHODS: TGB was heated in the presence of H(2)O(2). Degradation products were analyzed by liquid chromatography coupled to electrospray ionization multistage mass spectrometry (LC/ESI-MS(n)) and high-resolution mass spectrometry (HR-MS). RESULTS: This study showed that TGB was degraded by oxidative pathways involving attack of oxygen at different centers but mainly at the double bond of the molecule. The oxidative cascade reactions initiated by the epoxidation of the double bond of tiagabine led to dihydroxy, ketohydroxy and ketone derivatives as well as bisthiophene ketone. CONCLUSIONS: Nine degradation products of TGB were identified. Some diagnostic MS/MS product ions, characteristic of the piperidine or thiophene moiety, were highlighted.

Soluble epoxide hydrolase inhibition prevents coronary endothelial dysfunction in mice with renovascular hypertension.

OBJECTIVES: The study addresses the hypothesis that endothelial dysfunction in experimental arterial hypertension can be related to an alteration in epoxyeicosatrienoic acids (EETs) pathway and can be prevented by the inhibition of EETs degradation by soluble epoxide hydrolase (sEH). METHODS AND RESULTS: Arterial hypertension was induced in FVB/N mice by renal artery stenosis ('two-kidney-one-clip', 2K1C). Seven weeks after surgery, increased aortic pressures (Millar tonometer; Millar Instruments, Houston, Texas, USA) and cardiac hypertrophy (echocardiography) were present in 2K1C mice as compared with control mice. Left coronary artery endothelium-dependent relaxations to acetylcholine were decreased in 2K1C mice without modification in the relaxing responses to NS309 and NS1619, the openers of calcium-activated potassium channels mediating the hyperpolarizing effect of EETs. The inhibitors of the EET-synthesizing enzymes cytochrome P450 epoxygenases, fluconazole and N-methylsulfonyl-6-(2-propargyloxyphenyl)-hexanamide (MSPPOH), reduced the coronary relaxations to acetylcholine in control but not in 2K1C mice. The sEH expression was increased in 2K1C mice. The sEH inhibitor 12-(3-adamantan-1-yl-ureido)dodecanoic acid administered for 2 weeks starting 5 weeks after surgery in 2K1C mice (25 mg/l in drinking water) reduced aortic pressures and cardiac hypertrophy, improved the coronary relaxations to acetylcholine and restored the inhibitory effect of fluconazole and MSPPOH on acetylcholine-induced relaxations, without modifying the relaxations to NS309 and NS1619. CONCLUSION: These results demonstrate that a reduced EET-mediated relaxations related to an increased degradation by sEH contributes to coronary endothelial dysfunction in 2K1C hypertensive mice. Inhibiting sEH prevents endothelial dysfunction by restoring EET-mediated relaxations and thus, could represent a promising pharmacological intervention to limit cardiovascular morbidity and mortality in arterial hypertension.

Reduced cardiac remodelling and prevention of glutathione deficiency after omega-3 supplementation in chronic heart failure.

n-3 polyunsaturated fatty acids (omega-3) supplementation is associated with reduced cardiovascular mortality and post-infarction death. However, the impact of omega-3 supplementation in congestive heart failure (CHF) is still unknown. This study assesses the effects of omega-3 supplementation on left ventricular (LV) function and remodelling. We assessed, in rats with CHF induced by left coronary ligation, the effects of a 1-week and a 12-week supplementation with omega-3 (450 mg/kg per day) on LV hemodynamics, function and structure. Chronic omega-3 reduces total peripheral resistance due to an increase in cardiac output without modification of arterial pressure. Only chronic omega-3 reduces LV end-diastolic pressure and LV relaxation constant. Moreover, chronic omega-3 decreases LV systolic and diastolic diameters, LV weight and collagen density. Acute and chronic omega-3 increase LV γ-glutamyl-cysteine synthetase and oppose glutathione deficiency resulting in a reduction of myocardial oxidized glutathione. In experimental CHF, long-term omega-3 supplementation improves LV hemodynamics and function and prevents LV remodelling and glutathione deficiency. The latter might be one of the mechanisms involved, but whether other mechanism, independent of myocardial redox 'status', such as reduced inflammation, are implicated remains to be confirmed.