The ethanol extract of cocoa pod husk minimizes hyperalgesia and blood glucose levels in diabetic neuropathy model through transient receptor protein vanilloid (TRPV)-1

Abstract

Oxidative stress accumulation becomes a pathophysiological factor in diabetic neuropathy (DN), activating TRPV-1. Resveratrol in cocoa pod husk exhibits antioxidant activity that could be beneficial in DN. This study examined how the ethanol extract of cocoa pod husk (EECPH) affects DN in mice by targeting TRPV-1. Cocoa pod husk was extracted using 96 % ethanol with remaceration. The antioxidant activity was measured using DPPH. Mice were induced using alloxan 210 mg/kg BW i.p. At day 14, mice were randomized into seven groups: normal, diabetic, gabapentin 100 mg/kg BW, metformin 250 mg/kg BW, and EECPH (doses 250, 500, and 750 mg/kg BW). Treatments were administered orally, once daily for 14 days. The latency time and blood glucose levels were measured on days 7, 14, 21, and 28. On day 29, mice were sacrificed, and the blood, pancreas, and spinal cord were removed. Malondialdehyde, cholesterol, and serum glutamic oxaloacetic/pyruvic transaminase (SGOT/PT) were examined. Morphology of the spinal cord and pancreas was determined using hematoxylin and eosin staining. The expression of TRPV-1 was assessed using immunohistochemistry. The EECPH dose of 750 mg/kg BW showed the greatest effect in lowering hyperalgesia and blood glucose as well as cholesterol and SGOT/PT in mice. That dose also improved the histology of the pancreas and spinal cord by altering the expression of TRPV-1. It can be concluded that EECPH may lower the expression of TRPV-1 in the pancreas and spinal cord of mice. This activity was responsible of reducing hyperalgesia in DN mice.