A new xanthone from hulls of Garcinia mangostana and its cytotoxic activity / 中国中药杂志

Eight compounds were isolated from ethyl acetate fraction of 80% ethanol extract of the hulls of Garcinia mangostana by silica gel, Sephadex LH-20 column chromatography, as well as prep-HPLC methods. By HR-ESI-MS, MS, 1D and 2D NMR spectral analyses, the structures of the eight compounds were identified as 16-en mangostenone E(1), α-mangostin(2), 1,7-dihydroxy-2-(3-methy-lbut-2-enyl)-3-methoxyxanthone(3), cratoxyxanthone(4), 2,6-dimethoxy-para-benzoquinone(5), methyl orselinate(6), ficusol(7), and 4-(4-carboxy-2-methoxyphenoxy)-3,5-dimethoxybenzoic acid(8). Compound 1 was a new xanthone, and compound 4 was a xanthone dimer, compound 5 was a naphthoquinone. All compounds were isolated from this plant for the first time except compounds 2 and 3. Cytotoxic bioassay suggested that compounds 1, 2 and 4 possessed moderate cytotoxicity, suppressing HeLa cell line with IC_(50) va-lues of 24.3, 35.5 and 17.1 μmol·L~(-1), respectively. Compound 4 also could suppress K562 cells with an IC_(50) value of 39.8 μmol·L~(-1).

Revisión bibliográfica sobre la composición química y actividades farmacológicas del género Vismia (Guttiferae) / A review on the chemical composition and pharmacological activities of Vismia genus (Guttiferae)

Vismia genus is an important source of natural medicinal products, thus, information collected in this review is an attempt to cover the most recent developments in the ethnopharmacology, pharmacology and phytochemistry of this genus. Anthraquinones and other quinonoid derivates, terpenoids and volatile constituents have been reported as the major constituents isolated from different Vismia species. On the other hand, pharmacological studies carried out to date have revealed the variety of anti-plasmodium, antioxidant, antimicrobial and antifungical properties of extracts and pure isolated compounds of the different species tested. The information summarized in this paper intends to serve as a reference tool to practitioners in the fields of etnopharmacology and chemistry of natural products.

El género Vismia es una fuente importante de productos naturales medicinales, es por esto que la información reunida en la presente revisión cubre los estudios más recientes en la etnofarmacología, farmacología y fitoquímica de este género. Antraquinonas y otros derivados quinoides, terpenos y constituyentes volátiles han sido reportados como los compuestos mayormente aislados de las diferentes especies de Vismia. Por otro lado, los estudios farmacológicos realizados hasta los momentos muestran las diversas propiedades antiplasmodicas, antioxidantes, antimicrobianas y antifúngicas que presentan tanto los extractos como los compuestos puros aislados de las diferentes especies ensayadas. La información resumida en este documento intenta servir de material de apoyo para investigadores en los campos de la etnofarmacologia y la química de productos naturales.

Effects of gambogic acid on the regulation of nucleoporin Nup88 in U937 cells / 华中科技大学学报（医学）（英德文版）

In order to investigate the anti-leukemia effects of gambogic acid (GA) and its relation to the regulation of nucleoporin Nup88 in U937 cells in vitro, the inhibitory effect of GA on the growth of U937 cells was examined by using MTT assay. Apoptosis was detected by Annexin-V FITC/PI double-labeled cytometry. Cell cycle regulation was studied by propidium iodide method. Both flow cytometry (FCM) and RT-PCR were employed to assess the expression of Nup88, and the localization of Nup88 was determined by confocal microscopy. The results indicated that GA had strong inhibitory effect on cell proliferation and apoptosis induction activity in U937 cells in vitro in a time-and dose-dependent manner. The 24-h IC(50) value was (1.019+/-0.134) mg/L. Moreover, GA induced arrest of U937 cells in G(0)/G(1) phase. Over-expression of Nup88 was found in U937 cells, whereas GA could significantly down-regulate both the protein and mRNA levels of Nup88. Nup88 was diffusely distributed between nucleus and cytoplasm and was located at the cytoplasmic side of nuclear rim, and occasionally in cytoplasm. It is suggested that GA exerts its anti-leukemia effects by regulating the expression and distribution of nucleoporin Nup88. It promises to be new agent for the treatment of acute leukemia.

Cardioprotective effect of mangiferin on isoproterenol induced myocardial infarction in rats.

Isoproterenol (ISPH) induced myocardial infarction was confirmed by disturbances in serum and heart tissue marker enzymes such as lactate dehydrogenase (LDH), creatine phospho kinase (CPK), aspartate transaminase (AST) and alanine transaminase (ALT), increased level of lipid peroxidation and histopathological changes in the heart of ISPH administered rats. Pretreatment with mangiferin (10 mg/100 g body weight) for 28 days was found to ameliorate the effect of ISPH-induced pathological changes, reduced the lipid peroxide formation and retained the myocardial marker enzyme activities at near normal level. The above results indicate the cardioprotective effect of mangiferin against ISPH-induced myocardial infarction in rats.

Inhibitory effects of crude alpha-mangostin, a xanthone derivative, on two different categories of colon preneoplastic lesions induced by 1, 2-dimethylhydrazine in the rat.

The purpose of this study was to examine whether crude alpha-mangostin (a major xanthone derivative in mangosteen pericarp (Garcinia mangostana)) has short-term chemopreventive effects on putative preneoplastic lesions involved in rat colon carcinogenesis. The crude preparation was obtained by simple recrystallization of an ethylacetate extract of mangosteen pericarps. A total of 33 five-week-old male F344 rats were randomly divided into 5 experimental groups. Rats in groups 1-3 were given a subcutaneous injection of 1,2-dimethylhydrazine (DMH)(40 mg/kg body weight) once a week for 2 weeks. Starting one week before the first injection of DMH, rats in groups 2 and 3 were fed a diet containing 0.02% and 0.05% crude alpha-mangostin, respectively, for 5 weeks. Rats in group 4 also received the diet containing 0.05% crude alpha-mangostin, while rats in group 5 served as untreated controls. The experiment was terminated 5 weeks after the start. Dietary administration of crude alpha-mangostin at both doses significantly inhibited the induction and/or development of aberrant crypt foci (ACF) (P<0.05 for 0.02% crude alpha-mangostin, P<0.01 for 0.05% crude alpha-mangostin), when compared to the DMH-treated group (group 1). Moreover, treatment of rats with 0.05% crude alpha-mangostin significantly decreased dysplastic foci (DF) (P<0.05) and beta-catenin accumulated crypts (BCAC) (P<0.05), to below the group 1 values. The proliferating cell nuclear antigen (PCNA) labeling indices of colon epithelium and focal lesions in groups 2 and 3 were also significantly lower than in group 1 and this effect occurred in a dose dependent manner of the crude alpha-mangostin. This finding that crude alpha-mangostin has potent chemopreventive effects in our short-term colon carcinogenesis bioassay system suggests that longer exposure might result in suppression of tumor development.

Role of mucosal mast cells in visceral hypersensitivity in a rat model of irritable bowel syndrome

The involvement of mucosal mast cells (MMC) in the pathophysiology of irritable bowel syndrome (IBS) is still controversial. We aimed to re-evaluate the role of MMC in visceral hypersensitivity associated with IBS using a rat IBS model that develops the IBS symptom after a subsidence of acetic acid-induced colitis. No significant difference in the number of MMC was observed between normal rat colon and IBS rat colon. (61.7 +/-2.9/mm 2 in normal vs. 88.7 +/-13.3/mm 2 in IBS, p >0.29). However, the degranulation rate of MMC was significantly higher in IBS rat colon (49.5 +/-2.4% in normal vs. 68.8 +/-3.4% in IBS, p >0.05). Pretreatment of a mast cell stabilizer, doxantrazole (5 mg/kg, i.p.), reduced the degranulation rate of MMC and significantly attenuated visceral hypersensitivity to rectal distension in IBS rat, whereas it had no effect on the visceral sensory responses in normal rat. These results suggest that, although the number of MMC is not significantly changed in IBS rat colon, the higher degranulation rate of MMC is responsible for visceral hypersensitivity in this model IBS.