Regulation of osteoarthritis by omega-3 (n-3) polyunsaturated fatty acids in a naturally occurring model of disease

Osteoarthritis Cartilage. 2011 Sep;19(9):1150-7. doi: 10.1016/j.joca.2011.06.005. Epub 2011 Jul 1.


Objective: To examine effects of high omega-3 (n-3) polyunsaturated fatty acid (PUFA) diets on development of osteoarthritis (OA) in a spontaneous guinea pig model, and to further characterise pathogenesis in this model. Modern diets low in n-3 PUFAs have been linked with increases in inflammatory disorders, possibly including OA. However, n-3 is also thought to increases bone density, which is a possible contributing factor in OA. Therefore we aim to determine the net influence of n-3 in disease development.

Method: OA-prone Dunkin-Hartley (DH) Guinea pigs were compared with OA-resistant Bristol Strain-2s (BS2) each fed a standard or an n-3 diet from 10 to 30 weeks (10/group). We examined cartilage and subchondral bone pathology by histology, and biochemistry, including collagen cross-links, matrix metalloproteinases (MMPs), alkaline phosphatase, glycosaminoglycan (GAG), and denatured type II collagen.

Results: Dietary n-3 reduced disease in OA-prone animals. Most cartilage parameters were modified by n-3 diet towards those seen in the non-pathological BS2 strain - significantly active MMP-2, lysyl-pyridinoline and total collagen cross-links - the only exception being pro MMP-9 which was lower in the BS2, yet increased with n-3. GAG content was higher and denatured type II lower in the n-3 group. Subchondral bone parameters in the DH n-3 group also changed towards those seen in the non-pathological strain, significantly calcium:phosphate ratios and epiphyseal bone density.

Conclusion: Dietary n-3 PUFA reduced OA in the prone strain, and most disease markers were modified towards those of the non-OA strain, though not all significantly so. Omega-3 did not increase markers of pathology in either strain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkaline Phosphatase / metabolism
  • Animals
  • Disease Models, Animal
  • Fatty Acids, Omega-3 / pharmacology*
  • Fibrillar Collagens / metabolism
  • Glycosaminoglycans / metabolism
  • Guinea Pigs
  • Hindlimb / pathology
  • Knee Joint / metabolism
  • Knee Joint / pathology*
  • Matrix Metalloproteinases / metabolism
  • Menisci, Tibial* / drug effects
  • Menisci, Tibial* / pathology
  • Osteoarthritis / drug therapy*
  • Osteoarthritis / metabolism
  • Osteoarthritis / pathology


  • Fatty Acids, Omega-3
  • Fibrillar Collagens
  • Glycosaminoglycans
  • Alkaline Phosphatase
  • Matrix Metalloproteinases