1-1-diphenyl-2-picrylhydrazyl and genipin

Genipin, the multipotent ingredient in Gardenia jasmenoides fruit extract (GFE), may be an effective candidate for treatment following stroke or traumatic brain injury (TBI). Secondary injury includes damage mediated by reactive oxygen species (ROS) and reactive nitrogen species (RNS), which can alter the biological function of key cellular structures and eventually lead to cell death. In this work, we studied the neuroprotective potential of genipin against damage stemming from ROS and RNS production in organotypic hippocampal slice cultures (OHSC), as well as its potential as a direct free radical scavenger. A 50 µM dose of genipin provided significant protection against tert-butyl hydroperoxide (tBHP), a damaging organic peroxide. This dosage of genipin significantly reduced cell death at 48 h compared to vehicle control (0.1% DMSO) when administered 0, 1, 6, and 24 h after addition of tBHP. Similarly, genipin significantly reduced cell death at 48 h when administered 0, 1, 2, and 6h after addition of rotenone, which generates reactive oxygen species via a more physiologically relevant mechanism. Furthermore, genipin significantly reduced both cell death and nitrite levels at 24 h caused by S-nitroso-N-acetylpenicillamine (SNAP), a direct nitric oxide (NO) donor, and successfully quenched 1,1-Diphenyl-2-picryl-hydrazyl (DPPH), a stable free radical, suggesting that genipin may act as a direct free radical scavenger. Our encouraging findings suggest that genipin should be tested in animal models of CNS injury with a significant component of ROS- and RNS-mediated damage, such as TBI and stroke, to assess its in vivo efficacy.

Topics: Analysis of Variance; Animals; Animals, Newborn; Ascorbic Acid; Biphenyl Compounds; Cell Death; Dose-Response Relationship, Drug; Hippocampus; Insecticides; Iridoids; Neuroprotective Agents; Nitric Oxide Donors; Organ Culture Techniques; Picrates; Reactive Nitrogen Species; Reactive Oxygen Species; Rotenone; S-Nitroso-N-Acetylpenicillamine; Time Factors

The seeds and the pulp of Gardenia volkensii yielded one new iridiod, namely 4-(2N-gardenamide)n-butanoic acid, together with the known iridoids genipin and genipin gentiobioside, the pterocarpin medicarpin, coumarins, phenylpropanoids, benzenoids and triterpenes. The structures of these were determined on the basis of spectroscopic data and by comparison of obtained data with those from literature. The fruit extracts of this plant exhibited moderate radical scavenging activity against DPPH radical and moderate lethality against brine shrimps (Artemia salina).

Topics: Animals; Artemia; Biphenyl Compounds; Butyrates; Butyric Acid; Chromatography, Thin Layer; Dose-Response Relationship, Drug; Free Radical Scavengers; Gardenia; Hydrazines; Iridoid Glycosides; Iridoids; Magnetic Resonance Spectroscopy; Molecular Structure; Picrates; Plant Extracts; Pyridones; Seeds