The Ameliorative Effect of Ashwagandha- Withania somnifera (L.) Dunal on park25 Induced Neurodegeneration in Drosophila melanogaster Parkinson’s Disease Model

Abstract

Ashwagandha - Withania somnifera (L.) Dunal is a perennial shrub belonging to the family Solanaceae. Ashwagandha has been used for over 3000 years in traditional Indian Ayurveda for treatment of various neurological, and stress disorders. The root of Ashwagandha (ASH) is regarded as a tonic, aphrodisiac, narcotic, diuretic, anthelmintic, astringent, thermogenic and stimulant. Ashwagandha with other herbal decoctions was recognized to treat Kampavatha (Parkinson’s Disease) since 18th century. With this wide array of ethnopharmacological relevance, Ashwagandha has been recognized as one of the prominent complementary and alternative medicine to treat many neurodegenerative diseases like Alzheimer’s (AD) and Parkinson’s disease (PD). There is a prominent increase in the cases of AD and PD all over the world and it demands the requirement of complementary and alternative herbal remedies with no/minimal side effects. Many genetic factors are responsible for the onset and progression of PD. Loss-of-function mutations in the parkin gene are a major cause of early onset of autosomal recessive juvenile parkinsonism (AR-JP). Drosophila park25 loss of function mutants exhibit significantly increased number of mitochondria-endoplasmic reticulum contacts and a significantly decreased number of dopaminergic neurons in the adult brain which is the main cause of PD condition. Several studies have demonstrated the ability of Ashwagandha in imparting neuroprotection, improved locomotory ability, memory and learning abilities. The challenge lies in scrutinizing the mechanism and the pathways involved in the neuroprotective properties of this well-known herb. Here in our study, we test the possible neuroprotective effect of Ashwagandha on park25 mutants of Drosophila using lifespan analysis and climbing disability as a disease marker. Parkinson’s mimicking flies were administered with aqueous extraction of Ashwagandha-root mixed with the fly food and subjected to negative geotaxis assay. We observed that there is a prominent increase in the climbing ability in park25 treated flies compared to its age-matched untreated flies. This is the first report showing that, aqueous extraction of Ashwagandha-root extract was able to ameliorate the disease phenotype in the park25 Drosophila Parkinson’s disease model.