title: Rhinacanthus nasutus extracts prevent glutamate and amyloid-β neurotoxicity in HT-22 mouse hippocampal cells: possible active compounds include lupeol, stigmasterol and β-sitosterol.
abstract: The Herb Rhinacanthus nasutus (L.) Kurz, which is native to Thailand and Southeast Asia, has become known for its antioxidant properties. Neuronal loss in a number of diseases including Alzheimer's disease is thought to result, in part, from oxidative stress. Glutamate causes cell death in the mouse hippocampal cell line, HT-22, by unbalancing redox homeostasis, brought about by a reduction in glutathione levels, and amyloid-β has been shown to induce reactive oxygen species (ROS) production. Here in, we show that ethanol extracts of R. nasutus leaf and root are capable of dose dependently attenuating the neuron cell death caused by both glutamate and amyloid-β treatment. We used free radical scavenging assays to measure the extracts antioxidant activities and as well as quantifying phenolic, flavonoid and sterol content. Molecules found in R. nasutus, lupeol, stigmasterol and β-sitosterol are protective against glutamate toxicity.
authors.affiliation: Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, 154 Rama I Rd, Pathumwan, Bangkok 10330, Thailand.
authors.forename: James M
authors.identifier: 0000-0003-2074-8262
authors.initials: JM
authors.lastname: Brimson
authors.affiliation: Department of Clinical Microscopy, Faculty of Allied Health Sciences, Chulalongkorn University, 154 Rama I Rd, Pathumwan, Bangkok 10330, Thailand.
authors.forename: Sirikalaya J
authors.initials: SJ
authors.lastname: Brimson
authors.affiliation: Department of Biology and Biochemistry, Faculty of Science, University of Bath, Bath BA2 7AY, UK.
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Brimson
authors.affiliation: Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, 154 Rama I Rd, Pathumwan, Bangkok 10330, Thailand.
authors.forename: Varaporn
authors.initials: V
authors.lastname: Rakkhitawatthana
authors.affiliation: Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, 154 Rama I Rd, Pathumwan, Bangkok 10330, Thailand.
authors.forename: Tewin
authors.identifier: 0000-0003-4177-2165
authors.initials: T
authors.lastname: Tencomnao
mesh_terms: D027901:Acanthaceae / Q000378:metabolism*; D000544:Alzheimer Disease / Q000188:drug therapy / Q000473:pathology; D016229:Amyloid beta-Peptides; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D002460:Cell Line; D018698:Glutamic Acid / Q000633:toxicity; D005978:Glutathione / Q000378:metabolism; D006624:Hippocampus / Q000166:cytology; D051379:Mice; D018696:Neuroprotective Agents / Q000494:pharmacology; D020258:Neurotoxicity Syndromes / Q000188:drug therapy* / Q000517:prevention & control; D018384:Oxidative Stress / Q000187:drug effects; D053978:Pentacyclic Triterpenes / Q000494:pharmacology*; D010936:Plant Extracts / Q000494:pharmacology; D018515:Plant Leaves / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D012855:Sitosterols / Q000494:pharmacology*; D013265:Stigmasterol / Q000494:pharmacology*; D000094042:Lupanes
chemical_list: D016229:Amyloid beta-Peptides; D000975:Antioxidants; D018698:Glutamic Acid; D005978:Glutathione; D018696:Neuroprotective Agents; D053978:Pentacyclic Triterpenes; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D012855:Sitosterols; D013265:Stigmasterol; C025473:gamma-sitosterol; C010480:lupeol; D000094042:Lupanes