title: Alkaloids from the hook-bearing branch of Uncariarhynchophylla and their neuroprotective effects against glutamate-induced HT22 cell death.
abstract: One new alkaloid, 4-geissoschizine N-oxide methyl ether (1), was isolated from the EtOH extract of the hook-bearing branch of Uncariarhynchophylla, together with 10 known alkaloids, 3-epi-geissoschizine methyl ether (2) isolated from U.rhynchophylla for the first time, geissoschizine methyl ether (3), 4-hirsuteine N-oxide (4), hirsuteine (5), hirsutine (6), 3α-dihydro-cadambine (7), 3β-isodihydro-cadambine (8), cadambine (9), strictosamide (10), and akuammigine (11). The structures were elucidated by spectroscopic methods including UV, ESI-QTOF MS, NMR, and circular dichroism experiments. Neuroprotective effects of 1-9 were investigated against 3 mM glutamate-induced HT22 cell death. The activity assay showed that 2, 3, 5, and 6 exhibited potent neuroprotective effects against glutamate-induced HT22 cell death. However, only weak neuroprotective activities were observed for 1, 4, 7, 8, and 9.
authors.affiliation: a Department of Traditional Chinese Medicines , Shenyang Pharmaceutical University , Shenyang 110016 , China.
authors.forename: Wen
authors.initials: W
authors.lastname: Qi
authors.forename: Si-Jia
authors.initials: SJ
authors.lastname: Yue
authors.forename: Jia-Hong
authors.initials: JH
authors.lastname: Sun
authors.forename: James W
authors.initials: JW
authors.lastname: Simpkins
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.forename: Dan
authors.initials: D
authors.lastname: Yuan
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D016923:Cell Death / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D018698:Glutamic Acid / Q000494:pharmacology*; D026121:Indole Alkaloids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D015394:Molecular Structure; D018696:Neuroprotective Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D019906:Nuclear Magnetic Resonance, Biomolecular; D032070:Uncaria / Q000737:chemistry*
chemical_list: C000592719:4-geissoschizine N-oxide methyl ether; D000470:Alkaloids; D004365:Drugs, Chinese Herbal; D026121:Indole Alkaloids; D018696:Neuroprotective Agents; C110832:geissoschizine methylether; C063774:hirsuteine; D018698:Glutamic Acid; C038369:hirsutine
keywords: HT22 cells; Uncariarhynchophylla; glutamate; indole alkaloids; neuroprotection