New Delhi, Jan. 31: Ashwagandha, a plant used for centuries in Ayurvedic medicine, cleaned out abnormal protein deposits in the brain and reversed damage and behavioural changes observed in Alzheimers disease when tested on mice, a team of Indian scientists announced today.
The scientists have shown through experiments on mice that extracts of Ashwagandha (Withania somnifera) can reverse within 30 days the abnormal accumulation of a protein, called beta-amyloid plaque, in the brain that is linked to Alzheimers disease.
The researchers at the National Brain Research Centre (NBRC) at Manesar in Haryana fed genetically-engineered mice, which had symptoms similar to those of Alzheimers disease, a daily oral dose of a cocktail of chemicals called withanosides and withanolides, extracted from Ashwagandha.
The extracts appeared to boost the synthesis of a special protein in the liver that acts as a chaperone and helps remove amyloid plaque from the brain. The scientists said a component of this protein slips into the bloodstream and draws the accumulated amyloid plaque out of the brain into the bloodstream for eventual disposal and excretion from the body. The findings appear today in the US journal Proceedings of the National Academy of Sciences.
Its like vacuum cleaning the brain to get rid of unwanted amyloid plaque, said Vijayalakshmi Ravindranath, a senior neuroscientist at the Indian Institute of Science, Bangalore, who initiated the study eight years ago while she was director of the NBRC.
In their experiments, the scientists observed the elimination or reduction of amyloid plaque within the brain and an improvement or a complete reversal of behavioural deficiencies in the model mice, depending on the age of the animals.
Suvarna Alladi, a neurologist at the Nizam Institute of Medical Sciences in Hyderabad, who is not associated with the study, said all current therapy against Alzheimers disease directly target the brain. This is a novel strategy. Theyre targeting the liver to remove amyloid plaque from the brain. But this is also essentially an anti-amyloid therapy which currently appears to be a promising way ahead against Alzheimers disease.
Neurologists estimate that India has about four million people with dementia, the majority with Alzheimers disease. Current treatment involves pharmaceutical compounds designed to prevent the accumulation or the synthesis of amyloid plaque. But the best available therapy today does not cure Alzheimers disease, Alladi said.
While the use of Ashwagandha has been advocated for centuries in traditional medicine, the NBRC study is the first to show that its extracts reverse Alzheimers disease.
The results appeared so stunning that we requested an independent laboratory in Canada to validate them, Ravindranath told The Telegraph. Neurologist Edith Hamel at McGill University in Montreal and fellow researcher Jessica Mills repeated the experiments with a different model mouse and obtained similar results.
The NBRC team, including Neha Sehgal, Alok Gupta, Rupanagudi Khader Valli, and Shanker Datt Joshi collaborated with Delhi University plant chemistry experts Subhash Jain and Pankaj Khanna who extracted the withanosides and withanolides from the plant.
The researchers caution that the Ashwagandha extract is not ready for human trials yet. Ravindranath points out that the dose given to mice was very high ó about one gram per kilogram bodyweight of the animal.
The evidence with mice looks good. If this holds up in future studies, we should go into human trials, said Manjari Tripathi, a neurologist at AIIMS, New Delhi.
This is a desperate hunt for a devastating disease that robs its victims of memory and thinking capacity. There may also be other herbs waiting to be assessed through rigorous scientific research.