In vivo: |
Nat Prod Res. 2013 Mar;27(4-5):402-11. | The major indole alkaloid N,β-D-glucopyranosyl vincosamide from leaves of Psychotria leiocarpa Cham. & Schltdl. is not an antifeedant but shows broad antioxidant activity.[Pubmed: 22891663] | METHODS AND RESULTS:
N,β-D-glucopyranosyl Vincosamide (GPV), a major alkaloid of Psychotria leiocarpa, constitutes up to 2.5% of the dry weight in leaves. Alkaloid content was not elicited by mechanical wounding or jasmonate. At concentrations found in natural conditions or 2.5 fold higher, GPV did not inhibit herbivory in two unrelated generalist models (Helix aspersa and Spodoptera frugiperda) or in a specific interaction model (Heliconius erato fed with Passiflora suberosa). In situ staining assay showed quenching activity of hydrogen peroxide by GPV. Exposure of P. leiocarpa to acute UV-B stress did not change GPV or chlorophyll content, indicating high tolerance to this stress by the species.
CONCLUSIONS:
In vitro antioxidant tests against singlet oxygen, superoxide anions and hydroxyl radicals showed efficient quenching activity of the alkaloid. GPV was not effective as antifeedant, but it may act indirectly in P. leiocarpa protection against oxidative stress generated upon wounding, UV exposure and perhaps other environmental stresses. | Bioorg Med Chem Lett. 2013 Feb 15;23(4):959-62. | Cardioprotective potential of N,α-L-rhamnopyranosyl vincosamide, an indole alkaloid, isolated from the leaves of Moringa oleifera in isoproterenol induced cardiotoxic rats: in vivo and in vitro studies.[Pubmed: 23321560] | Hitherto unknown protective effect of N,α-L-rhamnopyranosyl Vincosamide (VR), isolated from Moringa oleifera leaves in isoproterenol (ISO)-induced cardiac toxicity was evaluated in rats.
METHODS AND RESULTS:
Oral administration of Hitherto unknown protective effect of N,α-L-rhamnopyranosyl Vincosamide (VR), isolated from Moringa oleifera leaves in isoproterenol (ISO)-induced cardiac toxicity was evaluated in rats. Oral administration of N,α-L-rhamnopyranosyl Vincosamide at 40 mg/kg for 7 days markedly reduced the ISO-induced increase in the levels of serum cardiac markers such as troponin-T, creatine kinase-MB, lactate dehydrogenase and glutamate pyruvate transaminase as well as cardiac lipid peroxidation with a parallel increase in the cellular antioxidants suggesting its cardio-protective and free radical scavenging potential, which was latter confirmed by in vitro study.
CONCLUSIONS:
Rats treated with test compound also improved the ISO-induced abnormal changes in ECG as well as in cardiac histology. |
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