alpha-linolenic-acid and Inflammation

Alpha-linolenic acid (ALA), an essential omega-3 polyunsaturated fatty acid found in plants, exerts neuroprotection and anti-inflammatory effects in chronic and acute CNS disease models. However, the underlying mechanisms are not yet understood. Since ALA is not incorporated into the brain, the observed health benefits may result from some of its metabolites. The putative formation of dihydroxylated ALA derivatives (called linotrins) was recently shown in vitro in the presence of lipoxygenases. However, the in vitro biosynthesis of linotrins was neither stereoselective nor quantitatively efficient for studying their physiological roles as enantiomeric pure forms. Herein, we report the first stereo-controlled synthesis that features regio- and stereoselective hydrometalations of alkynes for assembling the sensitive E,Z,E-conjugated trienes, as well as LC-MS investigations that provide evidence of linotrins occurrence in plants. Moreover, strong anti-inflammatory effects on microglia highlight the potential physiological importance of linotrins and open new perspectives in search of CNS therapeutics.

Topics: alpha-Linolenic Acid; Humans; Inflammation; Lipopolysaccharides; Microglia; Oxylipins

We previously found that vitamin K(3) (menadione, 2-methyl-1,4-naphthoquinone) inhibits the activity of human mitochondrial DNA polymerase γ (pol γ). In this study, we focused on juglone (5-hydroxy-1,4-naphthoquinone), which is a 1,4-naphthoquinone derivative, and chemically synthesized novel juglones conjugated with C2:0 to C22:6 fatty acid (5-O-acyl juglones). The chemically modified juglones enhanced mammalian pol inhibition and their cytotoxic and anti-inflammatory activities. The juglone conjugated with oleic acid (C18:1-acyl juglone) showed the strongest inhibition of DNA replicative pol α activity and human colon carcinoma (HCT116) cell growth in 10 synthesized 5-O-acyl juglones. C12:0-Acyl juglone was the strongest inhibitor of DNA repair-related pol λ, as well as the strongest suppression of the production of tumor necrosis factor (TNF)-α production induced by lipopolysaccharide (LPS) in the compounds tested. Moreover, this compound caused the greatest reduction in 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced acute inflammation in mouse ears. C12:0- and C18:1-Acyl juglones selectively inhibited the activities of mammalian pol species, but did not influence the activities of other pols and DNA metabolic enzymes tested. These data indicate that the novel 5-O-acyl juglones target anti-cancer and/or anti-inflammatory agents based on mammalian pol inhibition. Moreover, the results suggest that acylation of juglone is an effective chemical modification to improve the anti-cancer and anti-inflammation of vitamin K(3) derivatives, such as juglone.

Topics: Animals; Anti-Inflammatory Agents; Antineoplastic Agents; Cell Line, Tumor; DNA Polymerase beta; Enzyme Inhibitors; Humans; Inflammation; Lipopolysaccharides; Mice; Naphthoquinones; Tetradecanoylphorbol Acetate; Tumor Necrosis Factor-alpha

This protocol describes microsphere-based protease assays for use in flow cytometry and high-throughput screening. This platform measures a loss of fluorescence from the surface of a microsphere due to the cleavage of an attached fluorescent protease substrate by a suitable protease enzyme. The assay format can be adapted to any site or protein-specific protease of interest and results can be measured in both real time and as endpoint fluorescence assays on a flow cytometer. Endpoint assays are easily adapted to microplate format for flow cytometry high-throughput analysis and inhibitor screening.

Topics: Animals; Biotinylation; Flow Cytometry; Fluorescence Resonance Energy Transfer; Green Fluorescent Proteins; High-Throughput Screening Assays; Humans; Inflammation; Kinetics; Microspheres; Peptide Hydrolases; Peptides; Reproducibility of Results; Temperature