Neuroprotective effect of Thuja orientalis in haloperidol induced animal model of Parkinsons Disease

Abstract

Introduction: Neuro-inflammation, increased microglial activation and interaction and oxidative stress are the new targets for Parkinson management. Protective effect of NSAIDs and anti-oxidants has been demonstrated in many animal studies with inconclusive epidemiological reports. Thuja orientalis (TOFE) a common shrub found widely in India has shown neuro-protective effect against 6-OHDA induced toxicity on SH-SY cells. Aim and Objective: To assess and compare neuro-protective effect of TOFE with Ibuprofen and vitamin E in haloperidol induced rat models of Parkinson. Methodology: 6 adult male Sprague Dawley rats each in 4 groups were given Thuja orientalis (500mg/kg) / Ibuprofen (100mg/kg) and Vitamin E (35mg/kg) orally followed 1 hour latter by haloperidol. (2mg/kg.IP) for 7 days. Motor activity and rigidity were assessed with actophotometer and common bar test. Catatonia scoring was also done. One way ANOVA and Kruscal-Wallis tests followed by Dunns multiple comparison test were used for statistical significance of 0.05. Results: Significant reduction in motor activity was observed in all on 7^th day. Mild protection by thuja orientalis against motor rigidity was noted with p-value of 0.032 and against catatonia with 2.5 scoring. Conclusion: Neuroprotective effect shown in-vitro experiments by anti-oxidants and anti-inflammatory drugs did not show any significant effects in our in vivo animals study against clinical features as seen in Parkinsons disease. This inconclusive neuroprotective effect of standards and thuja observed signifies that all preclinical data from in vitro studies cannot be effectively extrapolated to in vivo animal and human studies due to many variations. Further probe in this aspect is suggested.