Cellular and molecular targets underpinning memory enhancement by ashwagandha

Abstract

The search for therapeutic candidates of memory disorders including gene targets and compounds both synthetic and natural has been a prime arena of neurobiology research. Amongst suggested therapeutic compounds, several herbal products with a long history of use in Ayurveda have gained attention in modern medicine. Ashwagandha (Withania somnifera) also referred to as "Queen of Ayurveda" is at the zenith of Ayurvedic herbs owing to its tremendous potential to recover memory decline in aging and neurodegenerative pathologies as well as enhance basal memory function of healthy individuals. Despite such promising effects, limited mechanistic evidences have hindered its acceptance in modern medicine. However, technical advances in neuroscience research over the past decade have filled-in some gaps in understanding of molecular and mechanistic biology of Ashwagandha effects. In this chapter, we highlight the studies that have deciphered the cellular and molecular mechanisms of memory enhancing potential of Ashwagandha in various disease models. Cellular targets of Ashwagandha include (i) activation of antioxidant defence system rescuing nerve cells from apoptosis, oxidative stress and DNA damage, (ii) induction of cholinergic system and (iii) up- regulation of memory linked neuroplasticity genes and neuronal arborisation. All of these molecular effects translate into increase in memory. Such multiple-module action has intrigued research to unravel upstream master regulators of Ashwagandha effects on gene expression, cell physiology and behaviour.