Neuroprotective Constituents from Hedyotis diffusa

Abstract

In a bioassay-guided search for neuroprotective compounds from medicinal plants, a MeOH extract of whole plants of Hedoytis diffusa yielded five flavonol glycosides, kaempferol 3-O-[2-O-(6-O-E-feruloyl)-beta-D-glucopyranosyl]-beta-D-galactopyranoside (1), quercetin 3-O-[2-O-(6-O-E-feruloyl)-beta-D-glucopyranosyl]-beta-D-galactopyranoside (2), quercetin 3-O-[2-O-(6-O-E-feruloyl)-beta-D-glucopyranosyl]-beta-D-glucopyranoside (3), kaempferol 3-O-(2-O-beta-D-glucopyranosyl)-beta-D-galactopyranoside (4), and quercetin 3-O-(2-O-beta-D-glucopyranosyl)-beta-D-galactopyranoside (5), and four O-acylated iridoid glycosides (6-9). Compounds 1 and 2 are previously unreported natural products, and all nine compounds exhibited significant neuroprotective activity in primary cultures of rat cortical cells damaged by L-glutamate.

Neuroprotective Effect of Kaempferol against a 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine-Induced Mouse Model of Parkinson's Disease

“…12) Kaempferol had earlier been shown to afford efficient neuroprotection against several apoptosis and necrosis-inducing insults, such as oxidized low-density lipoproteins 13,14) and L-glutamate. 15,16) Ishige et al 15) demonstrated that kaempferol efficiently blocked the increase in ROS associated with the oxidative stress caused by glutamate in the mouse hippocampal cell line HT-22. Filomeni et al 6) demonstrated that kaempferol exerted a strong and prolonged protective effect against rotenone toxicity, which was a classical toxin inducing PD.…”

Determination of Iridoid Glucosides for Quality Assessment of Herba Oldenlandiae by High-Performance Liquid Chromatography

“…4,5,7) Compound 3 was obtained as slightly yellow powder; mp 59-60°C; l max 312 (e 3365) (MeOH). The molecular formula was determined to be C 27 …”

“…Compare with those spectral data of the known compound 2 (Tables 3, 4), compound 3 was determined to have an additional methoxy group signal. 4,5,7) Therefore, the structure of 3 is de- No. termined to be E-6-O-p-coumaroyl scandoside methyl ester-10-methyl ether which was not reported previously.…”

Flavanone and Flavonol Glycosides from the Leaves of Thevetia peruviana and Their HIV-1 Reverse Transcriptase and HIV-1 Integrase Inhibitory Activities.

“…A reaction mixture (20 ml) containing 50 mM Tris-HCl (pH 8.3), 30 mM NaCl, 10 mM MgCl 2 , 5 mM DTT, 1.25 mg/ml (ca. 16 nM) poly(rA).oligo(dT) [12][13][14][15][16][17][18] as a template primer, 250 nM dTTP, 100 nM [methyl-3 H]dTTP (18.5 MBq/ml), 0.01 U/ml of RT, and 1.0 ml of a test compound dissolved in dimethyl sulfoxide (DMSO) (final concentration of 5%) was incubated at 37°C for 1 h. A control reaction was done under the same conditions without adding the test compound. The reaction was terminated by the addition of 20 ml of 0.02 M EDTA.…”

“…As regards the bioactivities of flavonol glycosides, quercetin and kaempferol 3-O-[(6-feruloyl)-glucopyranosyl-galactopyranoside] were reported to show neuroprotective activity in primary cultures of rat cortical cells damaged by L-glutamate, 18) whereas quercetin 3-O-[(6-feruloyl)-galactopyranoside] exhibited anti-superoxide production, 19) and anticomplement effects. 20) Feruloyl and sinapoyl glycosides showed radical scavenging activities against a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and inhibitory activity against the oxidation of linoleic acid.…”