Anti-Inflammatory and Antinociceptive Effects of Boesenbergia rotunda Polyphenol Extract in Diabetic Peripheral Neuropathic Rats

INTRODUCTION: Diabetic peripheral neuropathy (DPN) is still one of the most prevailing complication of diabetes and it affects a huge diabetic population. Boesenbergia rotunda is a ginger species that has both culinary and medicinal applications. Recent studies have revealed that B. rotunda has potential applications in diabetes, pain and inflammatory related disorders. As such this study investigated the potential of B. rotunda extract (EBR) in attenuating DPN in rats. METHODS: DPN was induced in male Sprague Dawley rats using a combination of 30% fructose solution and streptozotocin (40 mg/kg). Afterwards diabetic rats were treated with EBR (100 and 400 mg/kg) for 5 weeks. DPN was assessed using thermal hyperalgesia, cold and mechanical allodynia and rotarod test, while nociceptive responses were assessed by formalin and acetic acid test. In addition, serum proinflammatory cytokine levels were determined using ELISA kits. RESULTS: EBR displayed hypoglycemic effect by significantly reducing the blood glucose concentration of treated diabetic rats, while simultaneously alleviating the reduced body weight. Furthermore, EBR markedly alleviated thermal hyperalgesia, cold and mechanical allodynic responses as well as ameliorated motor coordination in the treated diabetic rats. In addition, EBR significantly reduced nociceptive responses in the formalin and acetic acid test, as well as decreased serum levels of proinflammatory cytokines (TNF-α and IL-1β). CONCLUSION: The results suggested that EBR exerted anti-inflammatory and anti-nociceptive effects, thus alleviating diabetic painful neuropathy.