Hepatocyte growth factor is a potential biomarker for osteoproliferation and osteoporosis in ankylosing spondylitis

SUMMARY: We explored relations between serum hepatocyte growth factor (HGF), disease activity, osteoproliferation, and bone mineral density (BMD) in ankylosing spondylitis (AS), in comparison with healthy controls. HGF was increased especially in male AS patients and smokers and associated with both lower BMD and more chronic radiographic changes in the spine. INTRODUCTION: Ankylosing spondylitis (AS) is characterized by both osteoproliferation and increased bone loss. Biomarkers are requested to predict the processes. The aims of this study were to compare serum levels of hepatocyte growth factor (HGF), matrix metalloproteinase-3 (MMP-3), and vascular endothelial growth factor (VEGF) in AS patients with healthy controls (HC) and to explore the associations with disease activity, osteoproliferation, and bone mineral density (BMD). METHODS: Serum from AS patients (modified NY-criteria) and HC was analyzed for HGF, MMP-3, and VEGF with ELISA. Disease activity parameters were collected. Osteoproliferation was assessed with modified Stoke Ankylosing Spondylitis Spine Score (mSASSS) and BMD was measured in femoral neck. RESULTS: Totally, 204 AS patients and 80 sex and age matched HC were included. Serum HGF was higher in the AS patients compared with the HC, whereas serum MMP-3 and VEGF were not. Serum HGF was also higher in smokers and in the male AS patients positively correlated with age, BASMI, and mSASSS, and negatively correlated with BMD. The biomarkers were all positively associated with ESR, CRP, and WBC. In multiple linear regression analysis serum HGF remained associated with higher mSASSS and lower BMD, after adjusting for age, sex, CRP, smoking, and body mass index. CONCLUSIONS: Serum HGF was increased in male AS patients and associated with higher mSASSS and lower BMD. In addition, serum HGF was positively associated with risk factors for osteoproliferation such as age, CRP and smoking. HGF could be a potential biomarker of importance for the bone metabolism in AS. TRIAL REGISTRATION: NCT00858819.