Dose Dependent Effects of Whole Blueberry on Cartilage Health and Pain in a Monosodium Iodoacetate (MIA) Induced Rat Model of Osteoarthritis

Abstract

Abstract Objectives The purpose of this study was to examine the dose-dependent effects of whole blueberry in a monosodium iodoacetate (MIA) induced rat model of Osteoarthritis (OA). There is no known cure for OA and the present pharmacological treatment options are limited and associated with adverse side effects. We hypothesize that the addition of whole blueberry into the diets of rats with MIA induced OA will reduce pain behavior and improve cartilage health. Methods A total of forty, 45-day-old female CD rats were used for this study. Thirty rats were injected with MIA to induce joint destruction associated with OA. Ten rats served as control without induction of joint destruction. The MIA induced rats were randomized into three groups consisting of 10 animals. All groups were fed a casein-based diet with two of the MIA induced groups receiving an addition of whole blueberry powder at 5% and 10%, respectively. All groups were fed the respective diets for 46 days. The animals were weighted weekly throughout the study period and food intake monitored and recorded. Fasted blood specimens and other tissues of interest were collected after euthanasia for analysis. Mechanical allodynia was assessed at four time points throughout the study to evaluate changes in pain behaviors. Results There were no difference in body weight between the four groups at baseline. After 46 days of feeding there was no significant change in body weight in either of the blueberry fed groups in comparison to the MIA rats. Plasma hyaluronic acid levels were higher in the MIA group in comparison to the blueberry treated groups. We observed a dose dependent decrease in hyaluronic acid levels with blueberry treatment, respectively. At baseline, the MIA group exhibited significant (P ≤ 0.05) mechanical allodynia compared to the control group. Mechanical allodynia was significantly (P ≤ 0.05) reduced after 40 days in the 10% whole blueberry treated group. Conclusions Incorporation of whole blueberry into the diets of rats with MIA-induced OA reduced hyaluronic acid concentration and pain sensitivity. These results suggest that whole blueberry may be an effective therapeutic alternative for improving joint health and alleviating pain associated with OA. Funding Sources Research Enhancement Program, Texas Woman's University.