Potential significance of polysaccharides from nerium indicum in neuroprotection

Abstract

Polysaccharides isolated from Traditional Chinese Medicine have long been known to have therapeutic effects on various diseases. At present, the majority of the research has been focus on their immune responses and anti-cancer properties. Little is known about the effects on neurons. Polysaccharides isolated from the flowers of Nerium indicum has been reported to have neurotrophic effect on PC12 cells, an effect similar to that of nerve growth factor. We aim to extend this line of study by examining whether these polysaccharides can provide significant effects in NEUROPROTECTION for neurons against serum-deprivation or BETA AMYLOID peptide (Aβ) toxicity. While neurons exposed to serum free medium resulted in DNA fragmentation and condensation by DAPI staining, pre-treatment of the polysaccharides significantly reduced the number of apoptotic neurons. Besides serum-deprivation, the polysaccharides could also significantly attenuated activation of CASPASE-3. Apart from their biological effects on neurons, we have also elucidated the chemical structures of these polysaccharides by various chemical techniques. The results strongly suggest that polysaccharides from N. indicum have potential clinical application as neuroprotective agent against toxic factors involved in aging and ALZHEIMER'S DISEASE.