(HealthDay News) — Potential mechanisms for the antiatherosclerotic activity of methotrexate (MTX) and adalimumab in rheumatoid arthritis (RA) have been identified, according to a study published in the May issue of Arthritis & Rheumatology.
Nicoletta Ronda, MD, PhD, from the University of Parma in Italy, and colleagues examined the influence of MTX and adalimumab treatment on serum cholesterol efflux capacity (CEC) and cholesterol-loading capacity (CLC) in patients with RA. The authors obtained sera from 34 MTX-treated RA patients and 22 adalimumab and MTX-treated patients before treatment, and after six weeks and six months of treatment. CEC and CLC were analyzed by radioisotopic and fluorometric techniques, respectively. In addition, the authors examined the influence of MTX and adalimumab on macrophage cholesterol efflux and uptake using human THP-1-derived macrophages.
The researchers observed a correlation between MTX treatment and increases in serum high-density lipoprotein (HDL), low-density lipoprotein, and total cholesterol levels, and with ATP-binding cassette G1-mediated and scavenger receptor class B type I (SR-BI)-mediated increases in CEC. There were no modifications in CLC with MTX treatment. There were correlations seen for adalimumab treatment and increases in serum HDL levels, a transient increase in SR-BI-mediated CEC, a transient reduction in ATP-binding cassette A1-mediated CEC, and a significant decrease in CLC. Adalimumab treatment was also associated with decreased macrophage cholesterol uptake in vitro.
“Antiatherosclerotic activity associated with MTX and adalimumab may be mediated by beneficial and complementary effects on lipoprotein functions and on macrophage cholesterol handling,” the authors write.
Two authors disclosed financial ties to pharmaceutical companies, including AbbVie, which partially funded the study. Abbott Laboratories also provided study funding.