title: Potential mechanisms leading to the abnormal lipid profile in patients with rheumatoid arthritis versus healthy volunteers and reversal by tofacitinib.
abstract: Tofacitinib is an oral JAK inhibitor for the treatment of rheumatoid arthritis (RA). Systemic inflammation is proposed to play a fundamental role in the altered lipid metabolism associated with RA; however, the underlying mechanisms are unknown. We undertook this study to compare cholesterol and lipoprotein kinetics in patients with active RA with those in matched healthy volunteers.
  
  
  
  This was a phase I open-label mechanism-of-action study. Cholesterol and lipoprotein kinetics were assessed with (13) C-cholesterol and (13) C-leucine infusions. RA patients were reevaluated after receiving oral tofacitinib 10 mg twice daily for 6 weeks.
  
  
  
  Levels of high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, total cholesterol, and apolipoprotein A-I (Apo A-I) as well as HDL cholesterol particle number were lower in RA patients (n = 36) than in healthy volunteers (n = 33). In contrast, the cholesterol ester fractional catabolic rate was higher in RA patients, but no differences were observed in cholesterol ester transfer protein, cholesterol ester production rate, HDL-associated Apo A-I fractional catabolic rate, or LDL-associated Apo B fractional catabolic rate. Following tofacitinib treatment in RA patients, the cholesterol ester fractional catabolic rate decreased and cholesterol levels increased. The decrease in cholesterol ester fractional catabolic rate correlated significantly with the increase in HDL cholesterol. Additionally, HDL cholesterol particle number increased and markers of HDL cholesterol function improved.
  
  
  
  This is the first study to assess cholesterol and lipoprotein kinetics in patients with active RA and matched healthy volunteers. The data suggest that low cholesterol levels in patients with active RA may be driven by increases in cholesterol ester catabolism. Tofacitinib treatment reduced cholesterol ester catabolism, thereby increasing cholesterol levels toward those in healthy volunteers, and markers of antiatherogenic HDL function improved.
authors.affiliation: University of California, Los Angeles.
authors.forename: Christina
authors.initials: C
authors.lastname: Charles-Schoeman
authors.forename: Roy
authors.initials: R
authors.lastname: Fleischmann
authors.forename: Jean
authors.initials: J
authors.lastname: Davignon
authors.forename: Howard
authors.initials: H
authors.lastname: Schwartz
authors.forename: Scott M
authors.initials: SM
authors.lastname: Turner
authors.forename: Carine
authors.initials: C
authors.lastname: Beysen
authors.forename: Mark
authors.initials: M
authors.lastname: Milad
authors.forename: Marc K
authors.initials: MK
authors.lastname: Hellerstein
authors.forename: Zhen
authors.initials: Z
authors.lastname: Luo
authors.forename: Irina V
authors.initials: IV
authors.lastname: Kaplan
authors.forename: Richard
authors.initials: R
authors.lastname: Riese
authors.forename: Andrea
authors.initials: A
authors.lastname: Zuckerman
authors.forename: Iain B
authors.initials: IB
authors.lastname: McInnes
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000188:drug therapy*; D015415:Biomarkers / Q000097:blood*; D002784:Cholesterol / Q000097:blood*; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D006814:Hungary; D008074:Lipoproteins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010880:Piperidines / Q000009:adverse effects / Q000627:therapeutic use*; D047428:Protein Kinase Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D011743:Pyrimidines / Q000009:adverse effects / Q000627:therapeutic use*; D011758:Pyrroles / Q000009:adverse effects / Q000627:therapeutic use*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D008074:Lipoproteins; D010880:Piperidines; D047428:Protein Kinase Inhibitors; D011743:Pyrimidines; D011758:Pyrroles; C479163:tofacitinib; D002784:Cholesterol