Tai-Ping Fan : Traditional medicine, memory and neurodegeneration. Cognitive and memory enhancing effects of Polygala and other extracts.
Duration: 28 mins 55 secs
Share this media item:
Embed this media item:
Embed this media item:
About this item
| Description: | Tai-Ping Fan (Pharmacology, University of Cambridge): Traditional medicine, memory and neurodegeneration. Cognitive and memory enhancing effects of Polygala and other extracts. |
|---|
| Created: | 2014-07-21 08:44 |
|---|---|
| Collection: | People and Plants |
| Publisher: | University of Cambridge |
| Copyright: | Glenn Jobson |
| Language: | eng (English) |
| Keywords: | People and Plants; Tai-Ping Fan; |
| Abstract: | Dr Tai-Ping Fan (Angiogenesis Laboratory, University of Cambridge): Traditional medicine, memory and neurodegeneration. Cognitive and memory enhancing effects of Polygala and other extracts
A projected 66 million people worldwide will be living with dementia by 2030, a figure set to rise to 115 million by 2050. With an escalating global cost of > US$600 billion per year for dealing with dementia, there is a great urgency to discover safe and efficacious treatments for Alzheimer’s Disease (AD). In 1992, Hardy and Higgins proposed the Amyloid Cascade Hypothesis of Alzheimer’s Disease. It postulates that build-up of toxic amyloid-β (Aβ) species initiates a series of events that culminates in neurodegeneration and symptoms. The exact sequence of events linking Aβ accumulation to aggregation of hyper-phosphorylated tau in different neuronal compartments, neuronal loss, synaptic dysfunction and symptoms remain incompletely understood. Current treatments include cholinesterase inhibitors (ChEIs) and N-methyl-D-aspartate (NMDA) receptor antagonists. Clinical research focuses on targeting amyloid: beta-secretase inhibitors; blocking aggregation; amyloid clearance and immunotherapy. Despite enormous R&D efforts, effective therapies for AD are still lacking. Two of the five licensed drugs for AD (galantamine and rivastigmine) are naturally-derived ChEIs, while Huperzine A is a dual ChEI and NMDA receptor antagonist. Recent studies have provided evidence suggesting that AD is related to chronic inflammation of brain microvasculature and neuronal network. Thus, therapeutic intervention to maintain the functional integrity of brain microvasculature is likely to augment the actions of ChEIs and drugs targeting Aβ-induced pathology. Polygala tenuifolia and Acorus calamus are medicinal herbs commonly used in Asia for memory enhancement and neuroprotection. In a randomized, double-blind, placebo-controlled trial, an extract of P. tenuifolia produced significant cognitive improvement in elderly humans. Recently, Fan and his Chinese collaborators demonstrated cognitive- and memory-enhancing effects of Polygala extracts in a mouse model of Aβ-induced amnesia, and aged mice, respectively. The roots of Polygala species contain terpenoids and xanthones as bioactive constituents. Others have shown tenuigenin to promote the proliferation and differentiation of hippocampal neural stem cells, while β-asarone from A. calamus attenuates Aβ-induced neuronal apoptosis. Using human cell lines, ‘omics and chemogenomics approaches, we are testing the hypothesis that phytochemicals derived from these and other plant extracts alleviate dementia through their vaso- and neuro-protective mechanisms by modulating multiple molecular targets on endothelial and neuronal cells. The optimization of, and drug development from, natural molecules from traditional medicine will improve the quality, safety and efficacy of potential prophylactic and therapeutic agents for AD and other diseases. |
|---|---|