The name ashwagandha comes from the sanskrit meaning 'horse-like smell'. Apparently, this name not only refers to the smell of the herb but also its strengthening and aphrodisiac qualities. It is often referred to as 'Indian ginseng' because it is used in much the same way in Indian Ayurvedic medicine as Panax ginseng in Traditional Chinese Medicine, although it is considered less stimulating. Primarily root, although berry, leaves and bark of Ashwagandha are used. Active Chemical components of Ashwagandha include Steroidal lactones (withanolides, withaferin A), alkaloids, flavonoids and saponins, Main beneficial actions of Ashwagandha herb is as an Adaptogen (modulates stress responses) This herb has been shown to attenuate the negative effects of chronic stress in rats, including hyperglycaemia, glucose intolerance, increase in plasma corticosteroid levels, gastric ulcerations, male sexual dysfunction, cognitive deficits, immunosuppression and mental depression. Animal trials have shown that a withanolide-free hydrosoluble fraction of Ashwagandha herb reduces the stress response induced both chemically and physically.
Ashwagandha herb also suppresses stress-induced increases in dopamine receptors in the corpus striatum and acts as a GABA-mimetic agent by binding to GABA receptors. GABA is a type of amino acid called Gamma Butyric Amino Acid. Ashwagandha herb is a chief neurotransmitter in the nervous system of the mammals. It plays a role in regulating the excitability of neurons throughout the nervous system. GABA - mimetic agents increase the available of GABA by mimicking the function of GABA. They have have relaxing, anti-anxiety, and anti-convulsive effects. Animal studies also suggest an ability to reduce adrenal weight and plasma cortisol levels thus potentially protecting against the negative effects of elevated cortisol levels in chronic stress and allostasis.
Nervous System Activity of Ashwagandha: Cognitive enhancement Memory enhancement has been confirmed by animal studies and appears to be mediated by a cholinergic effect. Increased cortical muscarinic acetylcholine receptor capacity has been observed in animals and humans with extracts of Ashwagandha. Several withanolides exert calcium antagonistic ability, together with anticholinesterase activity, by inhibiting butyrylcholinesterase and acetylcholinesterase enzymes. The presence of choline in the herb may also contribute to the production of acetylcholine and further increase cholinergic effects. Several animal studies indicate the potential for protection of neurons, including protection from neuronal injury in Parkinson's disease and promotion of dendrite formation.
One possible explanation is due to the antioxidant properties of this wonderful herb. In animal models of haloperidol-induced dyskinesia (chewing movements, tongue protrusion and buccal tremors), the reported benefits of withania appear to be due to its antioxidant rather than GABA-mimetic action. In vitro results suggest that withanolide A is able to reconstruct neuronal networks, including axons, dendrites, pre- and postsynapses, in the neurons.