withanolides and Memory-Disorders

Ashwagandha (root of Withania somnifera) has been used for many purposes, it is mainly considered a tonic in traditional Ayurvedic medicine. This review focuses on the effects of compounds isolated from Ashwagandha on dementia models and on the spinal cord injury model. Our study demonstrated that the active constituents, withanolide A, withanoside IV, and withanoside VI, restored presynapses and postsynapses, in addition to both axons and dendrites in cortical neurons after Abeta(25-35)-induced injury. In vivo, oral withanolide A, withanoside IV, and withanoside VI (10 micromol/kg/day for 12 days) improved Abeta(25-35)-induced memory impairment, neurite atrophy, and synaptic loss in the cerebral cortex and hippocampus in mice. Since spinal cord injury (SCI) is also difficult to treat, and therefore practical and curable strategies for SCI are desired. Oral treatment with withanoside IV improved locomotor functions in mice with SCI. In mice treated with withanoside IV (10 micromol/kg/day for 21 days), the axonal density and peripheral nervous system myelin level increased. The loss of CNS myelin and increase in reactive gliosis were not affected by withanoside IV. Additionally, sominone, an aglycone of withanoside IV, was identified as the main metabolite after oral administration of withanoside IV in mice. Withanolide A, withanoside IV, and withanoside VI are therefore important candidates for the therapeutic treatment of neurodegenerative diseases. In particular, withanoside IV was shown to control neurons as well as glial cells for reconstruction neuronal networks. To clarify key events in overcoming neurodegeneration, we are now studying the molecular targets and signal cascades of sominone.

Topics: Alzheimer Disease; Animals; Axons; Dendrites; Disease Models, Animal; Ergosterol; Humans; Medicine, Ayurvedic; Memory Disorders; Mice; Motor Activity; Neurodegenerative Diseases; Phytotherapy; Plant Extracts; Spinal Cord Injuries; Stimulation, Chemical; Synapses; Withania; Withanolides

In the present study we investigate the effect of Withania somnifera (WS) root extract and Withanolide A (WA) in restoring spatial memory deficit by inhibiting oxidative stress induced alteration in glutamergic neurotransmission. We demonstrate significant cellular loss in hippocampus of epileptic rats, visualized through decreased TOPRO stained neurons. Impaired spatial memory was observed in epileptic rats after Radial arm maze test. Treatment with WS and WA has resulted in increased number of TOPRO stained neurons. Enhanced performance of epileptic rats treated with WS and WA was observed in Radial arm maze test. The antioxidant activity of WS and WA was studied using superoxide dismutase (SOD) and Catalase (CAT) assays in the hippocampus of experimental rats. The SOD activity and CAT activity decreased significantly in epileptic group, treatment with WS and WA significantly reversed the enzymatic activities to near control. Real time gene expression studies of SOD and GPx showed significant up-regulation in epileptic group compared to control. Treatment with WS and WA showed significant reversal to near control. Lipid peroxidation quantified using TBARS assay, significantly increased in epileptic rats. Treatment with WS and WA showed significant reversal to near control. NMDA receptor expression decreased in epileptic rats. The treatment with WS and WA resulted in physiological expression of NMDA receptors. This data suggests that oxidative stress effects membrane constitution resulting in decreased NMDA receptor density leading to impaired spatial memory. Treatment with WS and WA has ameliorated spatial memory deficits by enhancing antioxidant system and restoring altered NMDA receptor density.

Topics: Animals; Catalase; Cognition Disorders; Dizocilpine Maleate; Epilepsy, Temporal Lobe; Excitatory Amino Acid Antagonists; Excitatory Amino Acid Transporter 1; Hemostasis; Immunohistochemistry; Male; Maze Learning; Memory Disorders; Oxidative Stress; Plant Roots; Rats; Rats, Wistar; Real-Time Polymerase Chain Reaction; Receptors, N-Methyl-D-Aspartate; Space Perception; Superoxide Dismutase; Thiobarbituric Acid Reactive Substances; Withania; Withanolides