Abyssinone V

Prenylated flavonoids of Erythrina lysistemon grown in Egypt.[Pubmed:12150799]

Phytochemistry. 2002 Aug;60(8):783-7.

Three prenylated flavonoid derivatives; 5,7,4'-trihydroxy-8-(3"'-methylbut-2"'-enyl)-6-(2"-hydroxy-3"-methylbut-3"enyl) isoflavone (isoerysenegalensein E), 5,7,2'-trihydroxy-4'-methoxy-5'-(3"-methylbut-2"-enyl) isoflavanone (lysisteisoflavanone), 5, 4'-dihydroxy-6-(3"'-methylbut-2"'-enyl)-2"-hydroxyisopropyl dihydrofurano [4",5":8,7] isoflavone (isosenegalensin), together with the four known flavonoids Abyssinone V-4'-methylether, alpinumisoflavone, wighteone and burttinone were isolated from the stem bark of Erythrina lysistemon Hutch. (Leguminosae). Structures were elucidated by spectroscopic methods.

Erythrina lysistemon-derived flavonoids account only in part for the plant's specific effects on rat uterus and vagina.[Pubmed:25153589]

J Basic Clin Physiol Pharmacol. 2015 May;26(3):287-94.

BACKGROUND: The stem bark ethyl acetate extract of Erythrina lysistemon was found to induce vaginal proliferation in ovariectomized rats orally treated. Alpinumisoflavone (AIF) and Abyssinone V-4'-methyl-ether (AME), isolated as its major constituents, were reported to separately provoke uterine growth and/or vaginal proliferation. The present study aimed at evaluating the effects of the mixture of AIF and AME (51 mg/kg [AIF]+153 mg/kg [AME]) following their relative abundance in the extract, in order to compare these effects to those of E. lysistemon. METHODS: The study was performed in ovariectomized rats treated intraperitoneally for 3 days. Estradiol valerate (E2 V) and AME were used for positive controls. Morphological and histological changes of animals' uterus and vagina were used as the hallmark of estrogenicity. RESULTS: E. lysistemon extract induced estrogen-like effects only on the uterus and significantly increased uterine wet weight (p<0.01) and uterine epithelial height (p<0.01). These results suggest a tissue-selective action of E. lysistemon extract depending on the route of administration. The mixture of AIF and AME induced E. lysistemon-like effects only at a dose of 1 mg/kg BW/d (0.25 mg/kg+0.75 mg/kg), although these effects were lower in magnitude (p<0.05) compared to those induced by E. lysistemon extract. CONCLUSIONS: Effects induced by the mixture of AIF and AME are analogous to those of E. lysistemon, but the low magnitude of these effects suggests that there are minor metabolites that interact with AIF and AME to provoke the specific effects of E. lysistemon.

Effects of alpinumisoflavone and abyssinone V-4'-methyl ether derived from Erythrina lysistemon (Fabaceae) on the genital tract of ovariectomized female Wistar rat.[Pubmed:22183714]

Phytother Res. 2012 Jul;26(7):1029-36.

Erythrina lysistemon is an African medicinal plant used as a palliative for problems in women. The crude extract of this plant was shown to exhibit estrogenic effects on the female rat reproductive tract and on cell cuture. Using classic chromatographic methods, two compounds have been isolated as major constituents of this extract: alpinumisoflavone (1) and Abyssinone V-4'-methyl ether (2). To determine whether both compounds are actives principles accounting for E. lysistemon effects, we applied the classic 3-day uterotrophic assay. We also carried out a ligand binding assay to determine whether the observed effects are estrogen receptor (ER) mediated. This study showed that whereas compound 1 displayed a fourfold preference for ERalpha, compound 2 bound ERalpha and ERbeta with a same affinity. The in vivo study showed that compound 1 increased the uterine wet weight by 182.23% (p < 0.01) and 71.79% (p < 0.05) at doses of 0.1 and 1 mg/kg BW/day respectively. The uterine epithelium thickened dose-dependently. Vaginal epithelial height also increased by 369.97 and 226.76% respectively (p < 0.01). Compound 2 acted only on the vagina and increased vaginal epithelial height by 244.56% (p < 0.01) at 1 mg/kg BW/day. These results suggest that compounds 1 and 2 are endowed with estrogenic properties accounting, at least in part, for E. lysistemon effects.

In vitro estrogenic activity of two major compounds from the stem bark of Erythrina lysistemon (Fabaceae).[Pubmed:22079771]

Eur J Pharmacol. 2012 Jan 15;674(2-3):87-94.

Plant-derived estrogen-like compounds, so called phytoestrogens, are given much attention due to their potential therapeutic use. In our previous work the ethylacetate extract of Erythrina lysistemon stem bark showed estrogenic effects on cell culture systems and ovariectomized Wistar rats. Using classical chromatographic methods, two constituents of Erythrina lysistemon have been isolated, referred to here as compounds 1 (alpinumisoflavone) and 2 (Abyssinone V-4'-methyl-ether), and their structures successfully determined using spectroscopic techniques. To test their binding affinity, the ligand binding assay has been used on estrogen alpha receptor, and estrogen beta receptor. Furthermore, transactivation assay in stably or transiently transfected human osteosarcoma (U2OS-estrogen alpha receptor and estrogen beta receptor) cells were used to examine their estrogenic activity. The regulations of some estrogen receptor target genes were also investigated. Both compounds bind to estrogen alpha and beta receptors. They significantly increased luciferase activity in a dose-dependent manner and induced the endogenous estrogen receptor-estrogen response element (ERE) interaction in U2OS-estrogen alpha receptor and estrogen beta receptor cells. In contrast, when co-treated with E2, compound 2 did not antagonize E2 activity in both systems whereas, 1 significantly suppressed E2 activity despite its low binding affinity to estrogen beta receptor. This result suggests a non-competitive mechanism. Both compounds also altered the expression of estrogen receptor target genes such as growth regulation by estrogen in breast cancer 1 (GREB1) and Cyclin D1 in breast cells. These results suggest that compounds 1 and 2 endow estrogenic activity and may be the active principles of Erythrina lysistemon.

Erythrina alkaloids and a pterocarpan from the bark of Erythrina subumbrans.[Pubmed:18171023]

J Nat Prod. 2008 Jan;71(1):156-8.

Three new erythrina alkaloids, (+)-10,11-dioxoerythratine (1), (+)-10,11-dioxoepierythratidine (2), and (+)-10,11-dioxoerythratidinone (3), and a new pterocarpan, 1-methoxyerythrabyssin II (4), were isolated from the bark of Erythrina subumbrans, together with seven known pterocarpans, erythrabyssin II, erybraedin A, erystagallin A, erycristagallin, erythrabissin-1, eryvarin A, and hydroxycristacarpone, three flavanones, 5-hydroxysophoranone, Abyssinone V, and lespedezaflavanone B, three triterpenes, sophoradiol, soyasapogenol B, and lupeol, and one isoflavanone, vogelin C. Their structures were elucidated on the basis of spectroscopic data. Some isolates were tested for antiplasmodial, antimycobacterial, and cytotoxic activities.

Alpinumisoflavone and abyssinone V 4'-methylether derived from Erythrina lysistemon (Fabaceae) promote HDL-cholesterol synthesis and prevent cholesterol gallstone formation in ovariectomized rats.[Pubmed:25683903]

J Pharm Pharmacol. 2015 Jul;67(7):990-6.

OBJECTIVES: Erythrina lysistemon was found to improve lipid profile in ovariectomized rats. Alpinumisoflavone (AIF) and Abyssinone V 4'-methylether (AME) derived from this plant induced analogous effects on lipid profile and decreased atherogenic risks. To highlight the molecular mechanism of action of these natural products, we evaluated their effects on the expression of some estrogen-sensitive genes associated with cholesterol synthesis (Esr1 and Apoa1) and cholesterol clearance (Ldlr, Scarb1 and Cyp7a1). METHODS: Ovariectomized rats were subcutaneously treated for three consecutive days with either compound at the daily dose of 0.1, 1 and 10 mg/kg body weight (BW). Animals were sacrificed thereafter and their liver was collected. The mRNA of genes of interest was analysed by quantitative real-time polymerase chain reaction. KEY FINDINGS: Both compounds downregulated the mRNA expression of Esr1, a gene associated with cholesterogenesis and cholesterol gallstone formation. AME leaned the Apoa1/Scarb1 balance in favour of Apoa1, an effect promoting high-density lipoprotein (HDL)-cholesterol formation. It also upregulated the mRNA expression of Ldlr at 1 mg/kg/BW per day (25%) and 10 mg/kg/BW per day (133.17%), an effect favouring the clearance of low-density lipoprotein (LDL)-cholesterol. Both compounds may also promote the conversion of cholesterol into bile acids as they upregulated Cyp7a1 mRNA expression. CONCLUSION: AIF and AME atheroprotective effects may result from their ability to upregulate mechanisms promoting HDL-cholesterol and bile acid formation.