F-2-Isoprostanes in HDL are bound to neutral lipids and phospholipids

Proteomic

Circulating 4‐f4t‐neuroprostane and 10‐f4t‐neuroprostane are related to mecp2 gene mutation and natural history in rett syndrome

Neuroprostanes, a family of non‐enzymatic metabolites of the docosahexaenoic acid, have been suggested as potential biomarkers for neurological diseases. Objective biological markers are strongly needed in Rett syndrome (RTT), which is a progressive X‐linked neurodevelopmental disorder that is mainly caused by mutations in the methyl‐CpG binding protein 2 (MECP2) gene with a predominant multisystemic phenotype. The aim of the study is to assess a possible association between MECP2 mutations or RTT disease progression and plasma levels of 4(RS)‐4‐F4t-neuroprostane (4‐F4t‐NeuroP) and 10(RS)‐10‐F4t‐neuroprostane (10‐F4t‐NeuroP) in typical RTT patients with proven MECP2 gene mutation. Clinical severity and disease progression were assessed using the Rett clinical severity scale (RCSS) in n = 77 RTT patients. The 4‐F4t‐NeuroP and 10‐F4t‐NeuroP molecules were totally synthesized and used to identify the contents of the plasma of the patients. Neuroprostane levels were related to MECP2 mutation category (i.e., early truncating, gene deletion, late truncating, and missense), specific hotspot mutations (i.e., R106W, R133C, R168X, R255X, R270X, R294X, R306C, and T158M), and disease stage (II through IV). Circulating 4‐F4t‐NeuroP and 10‐F4t‐NeuroP were significantly related to (i) the type of MECP2 mutations where higher levels were associated to gene deletions (p ≤ 0.001); (ii) severity of common hotspot MECP2 mutation (large deletions, R168X, R255X, and R270X); (iii) disease stage, where higher concentrations were observed at stage II (p ≤ 0.002); and (iv) deficiency in walking (p ≤ 0.0003). This study indicates the biological significance of 4‐F4t‐NeuroP and 10‐F4t‐NeuroP as promising molecules to mark the disease progression and potentially gauge genotype–phenotype associations in RTT

Phytoprostanes and phytofurans modulate COX-2-linked inflammation markers in LPS-stimulated THP-1 monocytes by lipidomics workflow

Inflammation is a fundamental pathophysiological process which occurs in the course of several diseases. The present work describes the capacity of phytoprostanes (PhytoPs) and phytofurans (PhytoFs) (plant oxylipins), present in plant-based foods, to modulate inflammatory processes mediated by prostaglandins (PGs, human oxylipins) in lipopolysaccharide (LPS)-stimulated THP-1 monocytic cells, through a panel of 21 PGs and PG's metabolites, analyzed by UHPLC-QqQ-ESI-MS/MS. Also, the assessment of the cytotoxicity of PhytoPs and PhytoFs on THP-1 cells evidenced percentages of cell viability higher than 90% when treated with up to 100 μM. Accordingly, 50 μM of the individual PhytoPs and PhytoFs 9-F1t-PhytoP, 9-epi-9-F1t-PhytoP, ent-16-F1t-PhytoP, ent-16-epi-16-F1t-PhytoP, ent-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 were evaluated on their capacity to modulate the expression of inflammatory markers. The results obtained demonstrated the presence of 7 metabolites (15-keto-PGF2α, PGF2α, 11β-PGF2α, PGE2, PGD2, PGDM, and PGF1α) in THP-1 monocytic cells, which expression was significantly modulated when exposed to LPS. The evaluation of the capacity of the individual PhytoPs and PhytoFs to revert the modification of the quantitative profile of PGs induced by LPS revealed the anti-inflammatory ability of 9-F1t-PhytoP, ent-9-D1t-PhytoP, 16-B1-PhytoP, 9-L1-PhytoP, and ent-9(RS)-12-epi-ST-Δ10-13-PhytoF, as evidenced by their capacity to prevent the up-regulation of 15-keto-PGF2α, PGF2α, PGE2, PGF1α, PGDM, and PGD2 induced by LPS. These results indicated that specific plant oxylipins can protect against inflammatory events, encouraging further investigations using plant-based foods rich in these oxylipins or enriched extracts, to identify specific bioactivities of the diverse individual molecules, which can be useful for nutrition and health in the frame of well-defined pathophysiological processes

F2-Dihomo-isoprostanes as potential early biomarkers of lipid oxidative damage in Rett syndrome.

Oxidative damage has been reported in Rett syndrome (RTT), a pervasive development disorder mainly caused in up to 95% of cases by mutations in the X-linked methyl-CpG binding protein 2 (MeCP2) gene. Herein, we have synthesized F2-dihomo-isoprostanes (F2-dihomo-IsoPs), peroxidation products from adrenic acid (AdA, 22:4 n-6), a known component of myelin, and tested the potential value of F2-dihomo-IsoPs as a novel disease marker and its relationship with clinical presentation, and disease progression. F2-dihomo-IsoPs were determined by a gas chromatography/negative ion chemical ionization tandem mass spectrometry. Newly synthetized F2-dihomo-IsoP isomers (ent-7(RS)-F2t-dihomo-IsoP and 17-F2t-dihomo-IsoP) were used as reference standards. The measured ions were the product ions at m/z 327 derived from the [M-181]- precursor ions (m/z 597) produced from both the derivatized ent-7(RS)-F2t-dihomo-IsoP and 17-F2t-dihomo-IsoP. Average plasma F2-dihomo-IsoP levels in RTT were about 1 order of magnitude higher than in healthy controls, being higher in typical RTT as compared to RTT variants, with a remarkable increase of about 2 orders of magnitude in patients at the earliest stage of the disease followed by a steady decrease during the natural clinical progression. These data indicate for the first time that quantification of F2-dihomo-IsoPs in plasma represents an early marker of the disease and may provide a better understanding of the pathogenic mechanisms behind the neurological regression in patients with RTT

Metabolic fingerprinting as an indicator of biodiversity: towards understanding inter-specific relationships among Homoscleromorpha sponges

International audienceSponges are an important source of secondary metabolites showing a great diversity of structures and biological activities. Secondary metabolites can display specificity on different taxonomic levels, from species to phylum, which can make them good taxonomic biomarkers. However, the knowledge available on the metabolome of non-model organisms is often poor. In this study, we demonstrate that sponge chemical diversity may be useful for fundamental issues in systematics or evolutionary biology, by using metabolic fingerprints as indicators of metabolomic diversity in order to assess interspecific relationships. The sponge clade Homoscleromorpha is particularly challenging because its chemistry has been little studied and its phylogeny is still debated. Identification at species level is often troublesome, especially for the highly diversified Oscarella genus which lacks the fundamental characters of sponge taxonomy. An HPLC–DAD–ELSD–MS metabolic fingerprinting approach was developed and applied to 10 Mediterranean Homoscleromorpha species as a rapid assessment of their chemical diversity. A first validation of our approach was to measure intraspecific variability, which was found significantly lower than interspecific variability obtained between two Oscarella sister-species. Interspecific relationships among Homoscleromorpha species were then inferred from the alignment of their metabolic fingerprints. The resulting classification is congruent with phylogenetic trees obtained for a DNA marker (mitochondrial COI) and demonstrates the existence of two distinct groups within Homoscleromorpha. Metabolic fingerprinting proves a useful complementary tool in sponge systematics. Our case study calls for a revision of Homoscleromorpha with further phylogenetic studies and identification of additional chemical synapomorphic characters

Abundance and bioactivity of cultured sponge-associated bacteria from the Mediterranean Sea

In this study, the search for new antibiotics was combined with quantitative ecological studies. The cultured fraction of the associated bacterial communities from ten different Mediterranean sponge species was investigated. To obtain quantitative and qualitative data of sponge-associated bacterial communities and to expand the cultured diversity, different media were used. The largest morphological diversity and highest yield of isolates was obtained by using oligotrophic media, which consisted of natural habitat seawater amended with (1% additional carbon sources. The dominant bacterial morphotypes were determined and bacterial isolates were tested for antimicrobial activity and identified using 16S rDNA sequencing. The sponge-associated most abundant morphotypes were all affiliated to the Alphaproteobacteria and showed antimicrobial activity against at least one of the tested strains. In contrast, the ambient seawater was dominated by Gammaproteobacteria. One single alphaproteobacterium, which was related to Pseudovibrio denitrificans, was shown to dominate the cultured community of at least six of the sponges. This designated MBIC3368-like alphaproteobacterium has been isolated from sponges before and seems to be restricted to associations with members of the phylum Porifera. It displays a weak and unstable antimicrobial activity, which gets easily lost during cultivation. However, this bioactive bacterium was present in the sponges by up to 106 cells per gram wet-weight sponge tissue and dominated the cultured fraction with up to 74%. The association of this alphaproteobacterium with sponges is probably evolutionary young and facultative and possibly involves biologically active secondary metabolites. Besides a demonstrated vertical transfer, additional horizontal transfer between the sponges is assumed. Members of the genus Bacillus displaying antimicrobial activity were found regularly, too. However, actinomycetes, which are known for their production of bioactive substances, were present in very low abundance