Open Access Research article

Histological and molecular characterisation of feline humeral condylar osteoarthritis

John M Ryan1, B Duncan X Lascelles2, Javier Benito2, Jon Hash2, Sionagh H Smith1, David Bennett3, David J Argyle1 and Dylan N Clements1*

Author Affiliations

1 Royal (Dick) School of Veterinary Studies and Roslin Institute, Division of Veterinary Clinical Sciences, Hospital for Small Animals, Easter Bush Veterinary Centre, The University of Edinburgh, Roslin, Midlothian EH25 9RG, Scotland

2 Department of Clinical Sciences, Comparative Pain Research Laboratory & Center for Comparative Medicine and Translational Research. College of Veterinary Medicine, North Carolina State University, 1060 William Moore Drive, Raleigh, NC 27606, USA

3 The School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bearsden Road, Bearsden, Glasgow G61 1QH, Scotland

For all author emails, please log on.

BMC Veterinary Research 2013, 9:110  doi:10.1186/1746-6148-9-110

Published: 4 June 2013

Abstract

Background

Osteoarthritis (OA) is a clinically important and common disease of older cats. The pathological changes and molecular mechanisms which underpin the disease have yet to be described. In this study we evaluated selected histological and transcriptomic measures in the articular cartilage and subchondral bone (SCB) of the humeral condyle of cats with or without OA.

Results

The histomorphometric changes in humeral condyle were concentrated in the medial aspect of the condyle. Cats with OA had a reduction in articular chondrocyte density, an increase in the histopathological score of the articular cartilage and a decrease in the SCB porosity of the medial part of the humeral condyle. An increase in LUM gene expression was observed in OA cartilage from the medial part of the humeral condyle.

Conclusions

Histopathological changes identified in OA of the feline humeral condyle appear to primarily affect the medial aspect of the joint. Histological changes suggest that SCB is involved in the OA process in cats. Differentiating which changes represent OA rather than the aging process, or the effects of obesity and or bodyweight requires further investigation.

Keywords:
Osteoarthritis; Feline; Humeral condyle; Gene expression; Histomorphometry