title: Naringin inhibits matrix metalloproteinase-9 expression and AKT phosphorylation in tumor necrosis factor-alpha-induced vascular smooth muscle cells.
abstract: Citrus fruits are high in naringin, which has a beneficial effect on cardiovascular diseases. However, the matrix metalloproteinase-9 (MMP-9) regulation involved in cell migration and invasion remains to be identified. Naringin inhibited tumor necrosis factor-alpha (TNF-alpha)-induced expression of MMP-9, under 10-25 microM concentration conditions in vascular smooth muscle cells (VSMC). The TNF-alpha-induced invasion and migration of VSMC were inhibited by naringin. Furthermore, naringin suppressed TNF-alpha-mediated release of interleukin-6 and -8 (IL-6 and IL-8). However, naringin (10-25 microM) treatment of VSMC in the presence of TNF-alpha did not affect cell growth and apoptosis. In additional experiments, naringin reduced the transcriptional activity of activator protein-1 and nuclear factor kappaB (NF-kappaB), which are two important nuclear transcription factors that are involved in MMP-9 expression. Also, naringin treatment blocked PI3K/AKT/mTOR/p70S6K pathway in TNF-alpha-induced VSMC. Treatment of aglycone naringenin (10-25 microM) had same effect on the levels of MMP-9 expression, invasion, migration, and AKT phosphorylation in TNF-alpha-induced VSMC, compared with naringin treatment. These results suggest that naringin represses PI3K/AKT/mTOR/p70S6K pathway, invasion and migration, and subsequently suppresses MMP-9 expression through the transcription factors NF-kappaB and activator protein-1 in TNF-alpha-induced VSMC. These novel findings provide a theoretical basis for the preventive use of naringin for atherosclerosis disease.
authors.affiliation: Department of Food and Biotechnology, Chungju National University, Chungbuk, South Korea.
authors.forename: Eo-Jin
authors.initials: EJ
authors.lastname: Lee
authors.forename: Dong-Il
authors.initials: DI
authors.lastname: Kim
authors.forename: Wun-Jae
authors.initials: WJ
authors.lastname: Kim
authors.forename: Sung-Kwon
authors.initials: SK
authors.lastname: Moon
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D050197:Atherosclerosis / Q000517:prevention & control; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D044950:Flavanones / Q000494:pharmacology*; D007378:Interleukins / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D032389:Myocytes, Smooth Muscle / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D011401:Promoter Regions, Genetic; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D038762:Ribosomal Protein S6 Kinases, 70-kDa / Q000378:metabolism; D058570:TOR Serine-Threonine Kinases; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors / Q000494:pharmacology*
chemical_list: D044950:Flavanones; D007378:Interleukins; D047908:Intracellular Signaling Peptides and Proteins; D016328:NF-kappa B; D018808:Transcription Factor AP-1; D014409:Tumor Necrosis Factor-alpha; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt; D038762:Ribosomal Protein S6 Kinases, 70-kDa; D058570:TOR Serine-Threonine Kinases; D020780:Matrix Metalloproteinase 9; C005273:naringenin; C005274:naringin