title: Active-dimeric form of lipoprotein lipase increases in the adipose tissue of patients with rheumatoid arthritis treated with prednisolone.
abstract: The synthesis, activity and mass of LPL in adipose tissue were studied in patients with rheumatoid arthritis (RA) treated with prednisolone (PSL) (PSL-treated group) and untreated patients with osteoarthritis (untreated group). LPL activity and mass in the extracts of acetone/ether powder of adipose tissue were 2.4 and 1.6 times, respectively, higher in the PSL-treated group than in the untreated group. There were no differences in the amount of 35S incorporated into LPL during the 2-h incubation of adipose tissue with [35S]methionine between PSL-treated and untreated groups. These results indicate that degradation of LPL was inhibited in the adipose tissue of the PSL-treated group. In the adipose tissue of the untreated group, 72% of the LPL was the inactive-monomeric form, which was eluted with 0.4-0.75 M NaCl from the heparin-Sepharose column, and 28% was the active-dimeric form, which was eluted with 0.8-1.2 M NaCl. In the adipose tissue of the PSL-treated group, 40% was inactive-monomeric, and 60% was active-dimeric. Thus, the relative amount of the active-dimeric form of LPL was increased in the adipose tissue of the PSL-treated group. Taken together, our present results indicate that the higher level of LPL activity in the PSL-treated group was a result of the inhibition of the degradation of the active-dimeric form.
authors.affiliation: Department of Orthopedic Surgery, School of Medicine, Ehime University, Shigenobu, Onsen-gun, Ehime 791-0295, Japan.
authors.forename: Teruki
authors.initials: T
authors.lastname: Kidani
authors.forename: Kenshi
authors.initials: K
authors.lastname: Sakayama
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Masuno
authors.forename: Nobuo
authors.initials: N
authors.lastname: Takubo
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Matsuda
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Okuda
authors.forename: Haruyasu
authors.initials: H
authors.lastname: Yamamoto
mesh_terms: D000273:Adipose Tissue / Q000201:enzymology*; D000368:Aged; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy / Q000378:metabolism*; D002845:Chromatography; D019281:Dimerization; D005260:Female; D006801:Humans; D008071:Lipoprotein Lipase / Q000032:analysis / Q000096:biosynthesis*; D008875:Middle Aged; D010003:Osteoarthritis / Q000378:metabolism; D011239:Prednisolone / Q000627:therapeutic use*
chemical_list: D000893:Anti-Inflammatory Agents; D011239:Prednisolone; D008071:Lipoprotein Lipase