Rhyncholphylline, an alkaloid isolated from Uncaria, shows potent inhibition of lipopolysaccharide (LPS)-induced NO production in rat primary microglial cells.IC50 value:Target:In vitro: Rhyncholphylline effectively suppresses release of proinflammatory cytokines in LPS-activated microglial cells and the underling molecular mechanism for the inhibition of microglial activation; Attenuated LPS-induced production of proinflammatory cytokines such as TNF-α and IL-1β as well as NO in mouse N9 microglial cells [1]. Rhynchophylline exerts it protective action against ischemia-induced neuronal damage by preventing NMDA, muscarinic M1, and 5-HT2 receptors-mediated neurotoxicity during ischemia [3].In vivo: The neuroprotective effect of rhynchophylline was investigated in a stroke model. Following pMCAO, rhynchophylline treatment not only ameliorated neurological deficits, infarct volume and brain edema, but also increased claudin-5 and BDNF expressions (p < 0.05). Moreover, rhynchophylline could activate PI3K/Akt/mTOR signaling while inhibiting TLRs/NF-κB pathway [2].
References:
[1]. Dan Yuan, et al. Anti-inflammatory effects of rhynchophylline and isorhynchophylline in mouse N9 microglial cells and the molecular mechanism. International ImmunopharmacologyVolume 9, Issues 13–14, December 2009, Pages 1549–1554
[2]. Houcai Huang, et al. Neuroprotective Effects of Rhynchophylline Against Ischemic Brain Injury via Regulation of the Akt/mTOR and TLRs Signaling Pathways. Molecules 2014, 19 (8): 11196-11210; doi:10.3390/molecules190811196
[3]. Tai-Hyun Kang, et al. Protective effect of rhynchophylline and isorhynchophylline on in vitro ischemia-induced neuronal damage in the hippocampus: putative neurotransmitter receptors involved in their action. Life SciencesVolume 76, Issue 3, 3 December 2004, Pages 331–343
[4]. Kinzo Matsumoto, et al. Suppressive effects of isorhynchophylline on 5-HT2A receptor function in the brain: Behavioural and electrophysiological studies. European Journal of PharmacologyVolume 517, Issue 3, 11 July 2005, Pages 191–199