Antifungal potential of extracts, fractions and compounds from Uvaria comperei (Annonaceae) and Oxyanthus unilocularis (Rubiaceae).

Phytochemical study of Uvaria comperei afforded an alkaloid, 8,9-dimethoxy-5H-phenanthridin-6-one (1), isolated and characterised (assignment of 1H and 13C NMR) for the first time from a natural source along with two flavonoids, (2S)-5-hydroxy-7,8-dimethoxyflavanone (2) and (2S)-7-hydroxy-5-methoxy-6,8-dimethylflavone (3). Clethric acid (4), oleanoic acid (5), ß-sitosterol 3-O-ß-D-glucopyranoside (9), ß-sitosterol palmitate (6) and a mixture of stigmasterol (7) and ß-sitosterol (8) were isolated from Oxyanthus unilocularis. The structures of these compounds were elucidated using modern spectroscopic techniques including1D and 2D Nuclear Magnetic Resonance (NMR) Spectroscopy (1H, 13C, 1H-1H COSY, HSQC, HMBC) and Mass Spectrometry. Some fractions and compounds from Uvaria comperei exhibited good antifungal activity against clinical isolates and standard strains of yeast species of Candida and Cryptococcus genera while extracts from Oxyanthus unilocularis displayed weak antifungal activity. The results obtained show that Uvaria comperei could be a potential source of antifungal drugs.

Epigarcinol and isogarcinol isolated from the root of Garcinia ovalifolia induce apoptosis of human promyelocytic leukemia (HL-60 cells).

BACKGROUND: Plants from garcinia genus have been used for centuries against several diseases. OBJECTIVE: This study aimed to investigate the mechanism of apoptosis induced by epigarcinol and isogarcinol isolated from the root of Garcinia ovalifolia (Clusiaceae) on human promyelocytic leukemia (HL-60 cells). METHODS: Epigarcinol and isogarcinol were isolated from the root of G. ovalifolia by using column chromatography method. The antiproliferative property of these molecules and fractions were assessed with 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The light fluorescence microscope was utilized to observe the morphological changes of HL-60 cells after 24 h treatment. Early apoptosis and cell cycle distribution were analyzed by using flow cytometry (FCM). RESULTS: The results showed that epigarcinol and isogarcinol inhibited the proliferation of HL-60 and PC-3 cells in a concentration-dependent manner with IC50 varying between 4 and 76 µg/mL depending on the cell line and the molecule. The apoptosis rate and the number of apoptotic cells significantly increased with the augmentation of the concentration of the molecules. The results of flow cytometry (FCM) indicated that epigarcinol and isogarcinol induced significant G2/S arrest of HL-60 cells, the disruption of mitochondrial membrane potential and reactive oxygen species (ROS) generation. CONCLUSION: These results indicated that epigarcinol and isogarcinol demonstrated in vitro antiproliferative properties and induce apoptosis of HL-60 cells which is related to the G2/S arrest, and it exerts its apoptotic effect through the loosing of mitochondrial membrane potential.

Regulation of CD1, Ki-67, PCNA mRNA expression, and Akt activation in estrogen-responsive human breast adenocarcinoma cell line, MCF-7 cells, by griffonianone C, an isoflavone derived from Millettia griffoniana.

CONTEXT: Millettia griffoniana Baill. (Fabaceae), which contains isoflavonoids like griffonianone C (Griff C), is commonly used in the folk medicine in Cameroon to treat various ailments. Possible health benefits of Griff C which include alleviation of menopausal symptoms, limitation of bone resorption, and lowering of the risks of cancer and cardiovascular diseases attracted our interest. OBJECTIVE: The effects of Griff C on the regulation of the expression of proliferation markers such as proliferating cell nuclear antigen (PCNA), cyclin D1 (CD1) and Ki-67 are investigated here. Its role in apoptosis or cell survival, through the phosphatidylinositol 3 kinase-Akt (PI3K-Akt) signaling pathway is further studied. MATERIALS AND METHODS: Semiquantitative real-time PCR was performed to analyze the effects of Griff C on gene expression in MCF-7 cells. Western blot analysis was used to assess the role of Griff C on the expression of phosphorylated Akt in MCF-7 cells. RESULTS: Griff C induced a 4.84-fold increase in the expression of Ki-67 mRNA at the concentration of 10(-8) M and a 3.90-fold increase of CD1 mRNA at 10(-7) M. Griff C slightly increased the phosphorylation of Akt at its serine 473 residue. Akt phosphorylation was inhibited by the PI3K inhibitor, LY294002, but not by the specific estrogen receptor antagonist, fulvestrant. DISCUSSION AND CONCLUSION: These findings suggest that Griff C can modulate proliferation of MCF-7 cells. Our results also suggest that Griff C can affect the PI3K-related signaling pathway. Thus, Griff C may exert part of its low proliferative and antiapoptotic effects by a nongenomic mode of action.

Modulation of some estrogen-responsive genes in the vena cava of ovariectomised Wistar rats by griffonianone C, an isoflavone derived from Millettia griffoniana Baill. (Fabaceae).

In the present study, we investigated whether griffonianone C (Griff C), extracted from root bark of Millettia griffoniana, changes the expression of several estrogen-responsive genes in the vena cava of ovariectomised rats. For this purpose, we subcutaneously administered Griff C (2, 10, or 20mg/kg/d BW), 17ß-estradiol (E2: 10µg/kg/d BW) as positive control, and a vehicle control respectively for three days. Relative expression levels of estrogen receptor α (ERα), progesterone receptor (PR), cyclooxygenase2 (Cox-2), vascular endothelial growth factor (VEGF), VEGF-receptor 2, angiotensin converting enzyme (ACE), endothelial NO synthase (eNOS), proliferating cell nuclear antigen (PCNA) and Ki67 mRNA extracted from the vena cava of these rats were quantified by real-time PCR. Results showed that Griff C up-regulated the expression of PR, ACE, ERα, VEGF, VEGFR2 and Ki67. However, the results of Cox-2, PCNA, and eNOS expression did not reach significance in the E2 and Griff C treated samples. These results show that griffonianone C regulated a few of the analysed genes in a similar fashion than estradiol; however, others showed a different pattern. This suggests that some of the biological effects attributed to M. griffoniana are mediated via ER pathway others may be mediated via other pathways.

Identification of an anti-inflammatory principle from the stem bark of Millettia versicolor.

The dichloromethane-soluble fraction of the methanol extract of the stem bark of Millettia versicolor Welw. (Leguminosae) has been shown to possess anti-inflammatory activity. The chromatographic fractionation and subsequent analysis of the spectroscopic data of this extract led to the isolation and identification of 2-acetyl-7-methoxynaphtho[2,3- b]furan-4,9-quinone (1) along with two known quinones. Pharmacological data demonstrate that compound 1 has relevant anti-inflammatory properties whereas the other two isolated compounds do not.

Griffonianone D, an isoflavone with anti-inflammatory activity from the root bark of Millettia griffoniana.

A new isoflavone, griffonianone D (1), and the previously known compounds durmillone and odorantin were isolated from a chloroform extract of the root bark of Millettia griffoniana. The structure of 1 was established as (7E)-(6",7"-dihydroxy-3",7"-dimethyloct-2"-enyl)oxy-4'-methoxyisoflavone on the basis of its spectral data. The chloroform extract of the root bark of M. griffoniana and compound 1 showed anti-inflammatory effects in different experimental models of inflammation.