Description
Rhynchophylline is an oxyindole alkaloid found in Uncaria sinensis. Rhynchophylline displays anti-arrhythmic, antithrombotic, antioxidative, and neuroprotective characteristics. This compound inhibits platelet aggregation, decreases channel activation and peak tail currents of voltage-gated hERG K+ channels on myocytes, and decreases Ca2+ currents of L-type Ca2+ channels. Additionally, rhynchophylline noncompetitively inhibits NMDA receptors and downregulates expression of the NR2B NMDA receptor subunit. As a result of these mechanisms, rhynchophylline protects against glutamate-induced neuronal death and acts as a vasodilator. This compound also decreases presence of superoxide anions and inhibits NF-κB activation through actions on IκB kinase, preventing epileptic seizures in vivo.
References
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Hsieh CL, Ho TY, Su SY, et al. Uncaria rhynchophylla and Rhynchophylline inhibit c-Jun N-terminal kinase phosphorylation and nuclear factor-kappaB activity in kainic acid-treated rats. Am J Chin Med. 2009;37(2):351-60. PMID: 19507277.
Gui L, Li ZW, Du R, et al. Inhibitory effect of rhynchophylline on human ether-a-go-go related gene channel. Sheng Li Xue Bao. 2005 Oct 25;57(5):648-52. PMID: 16220205.
Zhang WB, Chen CX, Sim SM, et al. In vitro vasodilator mechanisms of the indole alkaloids rhynchophylline and isorhynchophylline, isolated from the hook of Uncaria rhynchophylla (Miquel). Naunyn Schmiedebergs Arch Pharmacol. 2004 Feb;369(2):232-8. PMID: 14668978.
Shi JS, Kenneth HG. Effect of rhynchophylline on apoptosis induced by dopamine in NT2 cells. Acta Pharmacol Sin. 2002 May;23(5):445-9. PMID: 11978195.
Shimada Y, Goto H, Itoh T, et al. Evaluation of the protective effects of alkaloids isolated from the hooks and stems of Uncaria sinensis on glutamate-induced neuronal death in cultured cerebellar granule cells from rats. J Pharm Pharmacol. 1999 Jun;51(6):715-22. PMID: 10454049.
