Study On The Neuroprotective Components From Alpinia Oxyphylla

The central nervous system is vulnerable to the attack of reactive oxygen species and is resulted in oxidative stress,which eventually leads to the occurrence of neurodegenerative diseases.Therefore,natural products with antioxidant stress or antioxidant function are seemed as neuroprotective agents which might be displayed potential therapeutic effects on neurodegenerative diseases.Alpinia oxyphylla Miq.is a Zingiberaceae plant whose dried and mature fruits are known as alpinae oxyphyllae fructus.Traditional Chinese medicine recognises that it has the effect of intelligence,sedation and hypnosis.Mordern pharmacological studies suggest it exhibts neuroprotective,antioxidant and anti-inflammatory activities.Meanwhile,it mainly contains sesquiterpenoids,diarylheptanoids and volatile oils.However,there are few reports on the characteristic sesquiterpenoids and their neuroprotective effects.Hence,we selected A.oxyphylla as the research object and studied the chemical composition of the ethyl acetate extract of its 90%ethanol extract under the guidance of LC-MS.Fifty-one compounds were isolated from this part,including forty-two sesquiterpenoids,six diarylheptanoids and and three other compounds.There were eleven new sesquiterpenoids in which two guaiane sesquiterpenoids,six eudesmane sesquiterpenoids,one eremophilane sesquiterpenoid and two cadinane sesquiterpenoids were included.The neuroprotective activities of these compounds were evaluated on H₂O₂-induced SH-SY5Y cells.The results showed that the cell viabilities of compounds 2,4,14,15,23,26,30,31,41 and 42 at the concentration of5,10 and 20μM were more than 80%and were exceeded that of EGCG（positive control）which displayed obvious neuroprotective activity.Further activity studies showed that compounds 4,15,26 and 42 could significantly inhibit the productions of ROS.Compounds 15,26 and 42 could significantly reduce the levels of intracellular MDA and NO.This study enriched the chemical components from A.oxyphylla and evaluated the neuroprotective activities of sesquiterpenoids.It is expected to find potential lead compounds with therapeutic effects on neurodegenerative diseases to promote the development and utilization of A.oxyphylla.In the review part,we summarized the chemical constituents and biological activities of A.oxyphylla.A.oxyphylla mainly contain volatile oil,sesquiterpenoids,diarylheptanoids and other components in which sesquiterpenoids are the characteristic components and about eighty ones have been reported.A.oxyphylla display rich biological activities such as neuroprotective,antioxidant,antibacterial,and anti-inflammatory effects.