Effect of GreenshellTM Mussel on the Osteoarthritis Biomarkers and Inflammation in Healthy Postmenopausal Women: A Study Protocol for Randomized Double ‑ Blind Placebo ‑ Controlled Trial
Abstract Background: New Zealand Greenshell™ mussels (GSM; Perna canaliculus) has recently been shown to decrease cartilage degradation in a rat model of induced metabolic osteoarthritis (MetOA). However, this effect has not been investigated in human subjects. This study aims to determine the effect of GSM powder on biomarkers of cartilage metabolism, bone resorption, and inflammation in New Zealand healthy overweight/obese postmenopausal women. Method: Fifty overweight or obese (BMI 25-35 kg/m2) postmenopausal women (aged 55-75 years) will be recruited. They will be randomly assigned to receive 3 g/d whole meat GSM powder or placebo (sunflower seed protein) for 12 weeks. Data on socio-demographics, physical activity and dietary intake will be collected for each subject. Cartilage turnover biomarkers [(C-telopeptide of type II collagen (CTX-II), C-propeptide of type II procollagen (CPII), Cartilage oligomeric matrix protein (COMP)], and bone resorption marker (CTX-I) will be measured in blood and urine samples. Inflammatory status (hs-CRP and cytokine panel) will be assessed and iron status will be measured. Body composition including fat mass (FM), lean mass (LM) and fat percentage will be measured using dual-energy X-ray absorptiometry (DXA). Joint pain and knee function will be assessed using a 100 mm Visual Analogue Scale (VAS) and the Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire, respectively.Discussion: This trial will be the first to explore the effects of whole meat GSM powder on cartilage turnover, bone resorption and inflammation biomarkers in overweight/obese postmenopausal women. The results from this trial will provide evidence on the efficacy of GSM in prevention of OA. Trial registration: The study was registered with the Australian New Zealand Clinical Trials Registry (ANZCTR) with the number ACTRN12620000413921p. Registration date: 27/03/2020. https://www.anzctr.org.au/Trial/Update/Step1_Update.aspx?id=379291