title: Effects of low-intensity pulsed ultrasound on the expression and activity of hyaluronan synthase and hyaluronidase in IL-1β-stimulated synovial cells.
abstract: The purpose of this study is to examine effects of low-intensity pulsed ultrasound (LIPUS) on metabolism of hyaluronan (HA) in synovial membrane cells stimulated by IL-1β. Rabbit knee synovial membrane cell line, HIG-82, was cultured in medium with the presence or absence of 1 ng/mL IL-1β, and after 4 h the cell was exposed to LIPUS for 15 min. The mRNA levels of HA synthase (HAS) 2,3, hyaluronidase (HYAL) 2, and cyclooxygenase (COX)-2 were examined by real-time PCR analysis. Concentrations of HA and PGE₂ were quantified by use of enzyme linked immunosorbent assay (ELISA). The COX-2 level was analyzed by western blotting. Gene levels of HAS2 and HAS3 in IL-1β-stimulated cells were up-regulated significantly (p < 0.01) by LIPUS. HYAL2 mRNA was up-regulated by the treatment with IL-1β, whereas down-regulated significantly (p < 0.01) by the following LIPUS exposure. Furthermore, IL-1β stimulation enhanced COX-2 and PGE₂ expression as compared to the untreated control, and IL-1β-induced COX-2 and PGE₂ expression was inhibited by LIPUS. These results suggest that LIPUS enhanced HA synthesis and inhibited HYAL2 expression, leading to the accumulation of high-molecular weight HA. Therefore, LIPUS stimulation may be a better candidate as medical remedy to treat inflammatory joint diseases accompanied with HA degradation in synovial fluid.
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15 Kuramoto-cho, Tokushima 770-8504, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Nakamura
authors.forename: Shinji
authors.initials: S
authors.lastname: Fujihara
authors.forename: Tomoko
authors.initials: T
authors.lastname: Katsura
authors.forename: Kumiko
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Inubushi
authors.forename: Kotaro
authors.initials: K
authors.lastname: Tanimoto
authors.forename: Eiji
authors.initials: E
authors.lastname: Tanaka
mesh_terms: D000818:Animals; D001168:Arthritis / Q000378:metabolism / Q000628:therapy; D002460:Cell Line; D051546:Cyclooxygenase 2 / Q000096:biosynthesis; D015232:Dinoprostone / Q000096:biosynthesis; D005786:Gene Expression Regulation / Q000187:drug effects*; D014453:Glucuronosyltransferase / Q000096:biosynthesis*; D000076002:Hyaluronan Synthases; D006821:Hyaluronoglucosaminidase / Q000096:biosynthesis*; D053583:Interleukin-1beta / Q000494:pharmacology*; D007719:Knee Joint / Q000378:metabolism*; D011817:Rabbits; D013016:Sound; D013583:Synovial Membrane / Q000378:metabolism*; D013997:Time Factors; D014464:Ultrasonic Therapy / Q000379:methods; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D053583:Interleukin-1beta; D051546:Cyclooxygenase 2; D014453:Glucuronosyltransferase; D000076002:Hyaluronan Synthases; D006821:Hyaluronoglucosaminidase; D015232:Dinoprostone