Regulation of Arthritis Severity by the Acid Sphingomyelinase

Cell Physiol Biochem. 2017;43(4):1460-1471. doi: 10.1159/000481968. Epub 2017 Oct 16.

Abstract

Background/aims: Rheumatoid arthritis is a chronic autoimmune disease hallmarked by inflammation in synovial joints. Treatment is hampered by the lack of a cure and current disease-modifying drugs are associated with potentially severe toxicities.

Methods: We investigated arthritis severity by measuring joint swelling and pro-inflammatory cytokine production in a murine experimental model of inflammatory arthritis (antigen-induced arthritis). We analyzed acid sphingomyelinase knock-out mice and wild-type littermates, as well as mice treated with the pharmacological acid sphingomyelinase inhibitor amitriptyline.

Results: Genetic ablation or pharmacological inhibition of acid sphingomyelinase reduced joint swelling and levels of pro-inflammatory cytokines in the arthritic joint.

Conclusion: We identified acid sphingomyelinase as a novel druggable target in rheumatoid arthritis. Functional inhibitors of acid sphingomyelinase have been clinically used for decades, are well tolerated and suitable for long-term treatment. They would be immediately available for clinical development as a novel rheumatoid arthritis therapy.

Keywords: Acid sphingomyelinase; Ceramide; Inflammation; Rheumatoid arthritis.

MeSH terms

  • Amitriptyline / therapeutic use
  • Animals
  • Arthritis, Experimental / drug therapy
  • Arthritis, Experimental / genetics*
  • Arthritis, Experimental / pathology*
  • Arthritis, Rheumatoid / drug therapy
  • Arthritis, Rheumatoid / genetics
  • Arthritis, Rheumatoid / pathology
  • Disease Models, Animal
  • Gene Deletion
  • Joints / metabolism
  • Joints / pathology*
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Sphingomyelin Phosphodiesterase / antagonists & inhibitors
  • Sphingomyelin Phosphodiesterase / genetics*

Substances

  • Amitriptyline
  • ASMase, mouse
  • Sphingomyelin Phosphodiesterase