Antihyperalgesic effect of exercise is augmented by the oral pretreatment with extract of Casearia sylvestris in an animal model of osteoarthritis

Background/Purpose: Osteoarthritis (OA) is the main orthopedic disease to cause pain and edema in humans. This study evaluated the influence of complementary medicine on the hyperalgesia and edema induced by exercise in an animal model of OA as well as possible role for interleukin (IL)-1 beta to these outcomes. Methods: Mice (25-35 g) were subjected to intraplantar injection of Freund's complete adjuvant and were subjected to exercise and oral treatment with ethanolic crude extract of Casearia sylvestris (ECE-CS) or vehicle (alone or in combination) and evaluated through behavioral and biochemical tests. Results: At day 5, exercise and ECE-CS alone did not reduce hyperalgesia, while the combination of both enhanced this effect. In muscle and skin tissues from the treated paw of mice, both treatments alone or in combination reduced in similar extent the levels of IL-1 beta in relation to the control group. Conclusion: Association of both complementary therapies may bring benefits on pain associated with OA in humans.