Bioavailable phytoprostanes and phytofurans from Gracilaria longissima have anti-inflammatory effects in endothelial cells.

BACKGROUND: An array of bioactive compounds with health-promoting effects has been described in several species of macroalgae. Among them, phytoprostanes (PhytoPs) and phytofurans (PhytoFs), both autoxidation products of α-linolenic acid, have been seen to exert immunomodulatory and antiinflammatory activities in vitro. The purpose of this study was to explore the bioaccesibility, bioavailability, and bioactivity of PhytoPs and PhytoFs obtained from the edible red algae Gracilaria longissima, and to gain insight into the anti-inflammatory activity of their bioavailable fraction in human endothelial cells. METHODS: The PhytoPs and PhytoFs profile and concentration of G. longissima were determined by UHPLC-QqQ-MS/MS. Algal samples were processed following a standardised digestion method including gastric, intestinal, and gastrointestinal digestion. The bioavailability of the PhytoPs and PhytoFs in the characterized fractions was assessed in a Caco-2 cell monolayer model of the intestinal barrier. The inflammation response of these prostaglandin-like compounds in human endothelial cells, after intestinal absorption, was investigated in vitro. RESULTS: Simulated digestions significantly reduced the concentration of PhytoPs and PhytoFs up to 1.17 and 0.42 µg per 100 g, respectively, on average, although permeability through the Caco-2 cell monolayer was high (up to 88.2 and 97.7%, on average, respectively). PhytoP and PhytoF-enriched extracts of raw algae impaired the expression of ICAM-1 and IL-6 inflammation markers. The inflammation markers progressed in contrast to the relative concentrations of bioactive oxylipins, suggesting pro- or anti-inflammatory activity on their part. In this aspect, the cross-reactivity of these compounds with diverse receptors, and their relative concentration could explain the diversity of the effects found in the current study. CONCLUSIONS: The results indicate that PhytoPs and PhytoFs display complex pharmacological profiles probably mediated through their different actions and affinities in the endothelium.

Optimization of Free Phytoprostane and Phytofuran Production by Enzymatic Hydrolysis of Pea Extracts Using Esterases.

Given the growing interest in phytoprostanes (PhytoPs) and phytofurans (PhytoFs) in the fields of plant physiology, biotechnology, and biological function, the present study aims to optimize a method of enzymatic hydrolysis that utilizes bacterial and yeast esterases that allow the appropriate quantification of PhytoPs and PhytoFs. To obtain the highest concentration of PhytoPs and PhytoFs, a response surface methodology/Box-Behnken design was used to optimize the hydrolysis conditions. Based on the information available in the literature on the most critical parameters that influence the activity of esterases, the three variables selected for the study were temperature (°C), time (min), and enzyme concentration (%). The optimal hydrolysis conditions retrieved differed between PhytoPs (21.5 °C, 5.7 min, and 0.61 µg of enzyme per reaction) and PhytoFs (20.0 °C, 5.0 min, and 2.17 µg of enzyme per reaction) and provided up to 25.1- and 1.7-fold higher contents relative to nonhydrolyzed extracts. The models were validated by comparing theoretical and experimental values for PhytoP and PhytoF yields (1.01 and 1.06 theoretical/experimental rates, respectively). The optimal conditions were evaluated for their relative influence on the yield of individual nonesterified PhytoPs and PhytoFs to define the limitations of the models for obtaining the highest concentration of most considered compounds. In conclusion, the models developed provided valuable alternatives to the currently applied methods using unspecific alkaline hydrolysis to obtain free nonesterified PhytoPs and PhytoFs, which give rise to more specific hydrolysis of PhytoP and PhytoF esters, reducing the degradation of free compounds by classical chemical procedures.

Impact of Salicylic Acid Content and Growing Environment on Phytoprostane and Phytofuran (Stress Biomarkers) in Oryza sativa L.

Phytoprostanes (PhytoPs) and phytofurans (PhytoFs) are oxylipins synthesized by nonenzymatic peroxidation of α-linolenic acid. These compounds are biomarkers of oxidative degradation in plant foods. In this research, the effect of environment and supplementation with salicylic acid (SA) on PhytoPs and PhytoFs was monitored by ultra-high-performance liquid chromatography coupled to electrospray ionization and triple quadrupole mass spectrometry (UHPLC-ESI-QqQ-MS/MS) on seven rice genotypes from Oryza sativa L. subsp. japonica. The plastic cover environment and spray application with 1 and 15 mM SA produced a reduction in the concentration of most of these newly established stress biomarkers [9-F1t-PhytoP, ent-16-F1t-PhytoP, ent-16- epi-16-F1t-PhytoP, 9-D1t-PhytoP, 9- epi-9-D1t-PhytoP, 16-B1-PhytoP, 9-L1-PhytoP, ent-16( RS)-9- epi-ST-Δ14-10-PhytoF, ent-9( RS)-12- epi-ST-Δ10-13-PhytoF, and ent-16( RS)-13- epi-ST-Δ14-9-PhytoF] by 60.7% on average. The modification observed in the level of PhytoPs and PhytoFs differed according to the specific oxylipins and genotype, demonstrating a close linkage between genetic features and resistance to abiotic stress, to some extent mediated by the sensitivity of plants to the plant hormone SA that participates in the physiological response of higher plants to stress. Thus, in plants exposed to stressing factors, SA contribute to modulating the redox balance, minimizing the oxidation of fatty acids and thus the syntheis of oxylipins. These results indicated that SA could be a promising tool for managing the thermotolerance of rice crop. However, it remains necessary to study the mechanism of action of PhytoPs and PhytoFs in biochemical processes related to the defense of plants and define their role as stress biomarkers through a nonenzymatic pathway.

Comparative Study of the Phytoprostane and Phytofuran Content of indica and japonica Rice (Oryza sativa L.) Flours.

Phytoprostanes and phytofurans (PhytoPs and PhytoFs, respectively) are nonenzymatic lipid peroxidation products derived from α-linolenic acid (C18:3 n-3), considered biomarkers of oxidative degradation in plant foods. The present work profiled these compounds in white and brown grain flours and rice bran from 14 rice cultivars of the subspecies indica and japonica by ultrahigh performance liquid chromatography coupled to electrospray ionization and triple quadrupole mass spectrometry. For PhytoPs, the average concentrations were higher in rice bran (0.01-9.35 ng g-1) than in white and brown grain flours (0.01-1.17 ng g-1). In addition, the evaluation of rice flours for the occurrence PhytoFs evidenced average values 1.77, 4.22, and 10.30 ng g-1 dw in rice bran, brown grain flour, and white grain flour, respectively. A significant correlation was observed between total and individual compounds. The concentrations retrieved suggest rice bran as a valuable source of PhytoPs and PhytoFs that should be considered in further studies on bioavailability and bioactivity of such compounds.

Synthesis and discovery of phytofurans: metabolites of α-linolenic acid peroxidation.

Phytofurans are novel metabolites produced by non-enzymatic peroxidation of α-linolenic acid. An unprecedented Payne rearrangement-cyclization of a C2-symmetric bis-epoxide permitted construction of the core 3-hydroxy-2,5-disubstituted tetrahydrofuran. LC-MS/MS investigation provided evidence for the presence of phytofurans in nuts and seeds for the first time.

Prenatal exposure to the contaminant perfluorooctane sulfonate elevates lipid peroxidation during mouse fetal development but not in the pregnant dam.

Perfluorooctane sulfonate (PFOS), a member of the perfluorinated chemical family, has been convincingly demonstrated to affect lipid metabolism in animals and humans and readily crosses the placenta to exert its effects on the developing fetuses. While its exact mechanism is still not clear, PFOS exposure has long been suggested to exert its toxicity via oxidative stress and/or altered gene expression. Levels of PFOS and malondialdehyde in various organs and cell cultures have been widely determined as general indicators of non-specific lipid peroxidation after PFOS exposure. In this study, the oxidation of precise polyunsaturated fatty acids and their metabolites, derived from enzymatic and non-enzymatic pathways was determined following PFOS exposure in both adult and maternal/fetal mice. CD-1 mice were exposed to 3 mg/kg body weight/day of PFOS in corn oil by oral gavage until late gestation (GD17). We demonstrated that lipid peroxidation was particularly and exclusively affected in fetuses exposed to PFOS, but this was not the case in the maternal mice, where limited effects were observed in the enzymatic oxidation pathway. In this study, we demonstrated that PFOS-induced lipid peroxidation might have a greater impact in free radical generation in fetuses than in dams and could be responsible for affecting fetal development. In addition, antioxidant enzymes, such as superoxide dismutase and catalase, appeared to maintain oxidative stress homeostasis partially in adult mice exposed to PFOS. Taken together, our results might elucidate the mechanism of how PFOS induces oxidative stress in vivo.

[Changes in biological test practices after publication of national guidelines for lipid management among patients under statin treatment]. / Evolution de la prescription des examens de biologie après la diffusion de recommandations médicales sur les dyslipidémies.

BACKGROUND: Guidelines for screening and treatment of dyslipidemia were disseminated in September and October 2000 by the National Agency of Accreditation and of Evaluation in Health (ANAES) and the French Agency of Medical Safety of the Products of Health (AFSSAPS). It was confirmed that the specific biological test was the measurement of LDL Cholestérol. OBJECTIVE: To study changes in biological test practices after diffusion of guidelines among patients on statin therapy, using Health Insurance database on reimbursement of patients living in Ile-de-France region (8,534,623 social insurance contributors). METHODS: Two groups of patients were defined in the database from the codes for medication refunds during one month (March 2000 and March 2002). The first group named "new users" included patients starting statin therapy in March, in order to follow the biological test for screening. The second group named "long term users" included patients who had been treated by statin therapy for one year or more, in order to examine the biological follow-up of treatment. All lipid biological tests were recorded during one year, before March 2000 and March 2002. Changes in medical practices were noted as the percentage of the biological tests for "exploration of a lipidic anomaly" (EAL) with determination of LDL cholesterol. RESULTS: For new users the percentage of patients having had at least one EAL for screening purposes increased by 13.5 (39.9% in 2000 and 53.4% en 2002). For long term users the change was + 21.1 (38.3% in 2000 and 59.4% in 2002) during follow-up. CONCLUSION: An improvement in biological testing practices was noted after diffusion of guidelines.

Estimation of the abundance of the cadmium resistance gene cadA in microbial communities in polluted estuary water.

We describe herein a molecular method for estimating the abundance of the cadA gene, which encodes a Cd2+/ATPase protein transporter, in bacterial DNA extracted from samples of environmental water. Competitive polymerase chain reaction (cPCR) may be the most appropriate technique for assessing the prevalence of the cadA gene in microbial communities in highly heterogeneous and polluted environments, such as the Seine estuary (France). We describe the development of this method: (i) the choice of two specific primers, based on the sequences encoding the cadmium binding site and the ion channel domains; (ii) the construction of a competitor sequence and assessment of its amplification efficiency; and (iii) the estimation of the copy number of the cadA gene. The cadA content in the bacterial community is expressed as the number of gene copies per ng of total DNA extracted, which is independent of the DNA extraction yield. This molecular procedure was improved to analyze cadA levels in bacterial DNA extracted from estuary water accidentally contaminated with cadmium. Results revealed a subsequent increase in the copy number of the cadA gene in the microbial community.

Phenotypic differentiation of bifidobacteria of human and animal origins.

The phenotypes of 153 strains belonging or related to the genus Bifidobacterium were studied. These organisms included 38 collection strains and 115 wild strains (41 strains of human origin, 56 strains of animal origin, and 18 strains obtained from rivers or sewage). Our phenotypic analysis revealed seven main groups that were subdivided into 20 subgroups. Seven subgroups contained no type or collection strain. Among the human strains, the type strains of Bifidobacterium pseudocatenulatum and B. catenulatum fell into group I, which contained the type strains of B. adolescentis (subgroup Ib), B. dentium (subgroup Ic), and B. angulatum (ungrouped). The type strain of B. breve belonged to subgroup IIIa1, and the type strains of B. infantis and B. longum fell into subgroup IIIb1. Group VII comprised only wild strains that were isolated from human infant feces. Among the animal strains, group II consisted mainly of bifidobacteria that were isolated from pig feces and contained the type strains of B. suis (subgroup IIb), B. thermophilum (subgroup IIf), B. choerinum, and B. boum (ungrouped). Wild strains belonging to group V were isolated from pig, calf, cow, and chicken feces; this included the type strains of B. animalis (subgroup Va), B. magnum (subgroup Vb), B. pseudolongum, and B. globosum (subgroup Vc). The strains of human origin (groups I, III, and VII) were well separated from the animal strains (groups II, IV, and V). It was not surprising that the wild strains isolated from surface water or sewage were distributed in the animal groups as well as the human groups. Thus, bifidobacteria can be considered to be successful indicators of human or animal fecal pollution when they are correctly classified. The acidification patterns were not adequate to differentiate Bifidobacterium species, as determined previously by Mitsuoka (Bifidobacteria Microflora 3:11-28, 1984) and Scardovi (p. 1418-1434, in P. H. A. Sneath, N. S. Mair, M. E. Sharpe, and J. G. Holt, ed., Bergey's Manual of Systematic Bacteriology, vol. 2, 1986). However, enzymatic tests furnished new taxonomic criteria for the genus.

[Thermoresistance of Legionella]. / Thermorésistance des Legionella.

Cells of Legionella suspended in water were heated for 15 to 60 min, at temperatures between 40 and 70 degrees C, and their survival determined over 9 log-cycles. The survival curves were identical for the 6 strains, and were non-logarithmic. Implications of the resistance plateau observed are discussed.

[On the coliform organisms and their count in water supply analysis (author's transl)]. / A propos des coliformes et de la colimétrie des eaux d'alimentation.

Many psychrotrophic coliform organisms are isolated from samples of water supply. They are coming from water or soil and not from animal faeces. It is therefore necessary to identify coliform organisms to interpret accurately the results of potability analysis.

[Slaughterhouse waste waters and their influence on epidemiology (author's transl)]. / Les eaux usées des abattoirs et leur importance épidémiologique

A survey was carried out in 1972 and 1973 on the microbial composition of town, hospital and slaughterhouse waste waters. The investigation concerned concentration of heterotrophic bacteria, germ tests, of faecal contamination, and of the following pathogenic bacteria: Salmonella, Pseudomonas aeruginosa, Staphylococcus aureus.