Analgesic effect of chronic oral administration of aerial part of Marrubium Vulgare in diabetic rats

BACKGROUND AND OBJECTIVE: Considering the antidiabetic and anti-inflammatory effect of marrubium vulgare (MV), this study was designed to investigate the analgesic effect of MV on formalin-induced nociceptive response (standard formalin test) in diabetic rats. METHODS: Forty-eight rats were randomly divided into control, MV-treated control, diabetic, sodium salicylate (SS)-treated diabetic, sodium salicylate (SS)-treated control and MV-treated diabetic groups. For induction of diabetes, streptozotocin was used at a single dose. The treatment groups received oral administration of MV-mixed pelleted food (6.25%) for two months. FINDINGS: In this study, administration of sodium salicylate to control and diabetic groups caused a significant reduction in pain score in the second phase of formalin test (p<0.05 and p<0.01, respectively). On the other hand, administration of marrubium vulgare for two months to control and diabetic groups caused a significant reduction in pain score at both phases of the formalin test (21.3% (p<0.05) and 18.4% reductions (p<0.05)) in control and diabetic groups (17.6% (p<0.05) and 17.9% reductions (p< 0.05)) as compared to untreated control and diabetic groups.CONCLUSION: The results indicate that administration of marrubium vulgare could attenuate nociceptive score in an experimental model of diabetes mellitus and this may be considered as a potential treatment for painful diabetic neuropathy