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      Permanent link:
      https://www.ias.ac.in/article/fulltext/jbsc/037/02/0277-0287

    • Keywords

       

      Cholesterol; interfacial activity; phospholipase A2; quercetin; sphingomyelin

    • Abstract

       

      The goal of the present study is to elucidate the mechanism of quercetin on modulating Naja naja atra phospholipase A2 (PLA2) activities. Sphingomyelin inhibited PLA2 enzymatic activity and membrane-damaging activity against egg yolk phosphatidylcholine (EYPC), while cholesterol and quercetin abrogated the sphingomeyelin inhibitory effect. Quercetin incorporation led to a reduction in PLA2 enzymatic activity and membrane-damaging activity toward EYPC/sphingomyelin/cholesterol vesicles. Both cholesterol and quercetin increased detergent resistance and reduced membrane fluidity of EYPC/sphingomyelin vesicles. Quercetin reduced detergent insolubility but increased ordered lipid packing of EYPC/sphingomyelin/cholesterol vesicles. Acrylamide quenching studies and trinitrophenylation of Lys residues revealed that quercetin altered the membrane-bound mode of PLA2 differently upon absorption onto the membrane bilayers of different lipid compositions. However, 8-anilinonaphthalene sulphonate-binding assay revealed that quercetin marginally affected the interaction between active site of PLA2 with phospholipid vesicles. Collectively, our data indicate that membrane-inserted quercetin modulates PLA2 interfacial activity and membrane-damaging activity via its effects on membrane structure and membrane-bound mode of PLA2.

    • Author Affiliations

       

      Yi-Ling Chiou1 Shinne-Ren Lin2 Wan-Ping Hu3 Long-Sen Chang1

      1. Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan
      2. Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 807, Taiwan
      3. Department of Biotechnology, Kaohsiung Medical University, Kaohsiung 807, Taiwan
    • Dates

       
  • Journal of Biosciences | News

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