1,3,5,8‐Tetrahydroxy‐9H‐xanthen‐9‐one exerts its antiageing effect through the regulation of stress‐response genes and the MAPK signaling pathway

The antioxidative effects of 30 xanthone derivatives (XDs) ( XD‐ n , n = 1–30) in HepG2 cells were evaluated by the cellular antioxidant activity assay. Results showed that all XDs were antioxidants and 1,3,5,8‐tetrahydroxy‐9H‐xanthen‐9‐one ( XD‐2 ) was the most active antioxidant. The all‐oxygenated substituted xanthones extended the lifespan of wild‐type N2 nematodes under normal culture conditions and XD‐2 was the best one. XD‐2 eliminated excessive intracellular reactive oxygen species and enhanced the expression levels and activities of the antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase. XD‐2 inhibited the H₂O₂‐increased phosphorylation levels of c‐JUN N‐terminal kinase, extracellular signal‐regulated kinase, and p38 in HepG2 cells. In vivo, XD‐2 also extended the lifespan of wild‐type N2 nematodes under oxidative stress induced by paraquat, but failed in extending the lifespan of CF1038 (daf‐16 deletion) and AY102 (pmk‐1 deletion) mutant nematodes. It was revealed by real‐time polymerase chain reaction that the genes daf‐16, sir‐2.1, akt‐1, and age‐1 were all inhibited by paraquat stimuli, while XD‐2 reversed these inhibitions; in contrast, paraquat stimuli upregulated both the skn‐1 and pmk‐1 genes. However, treatment by  XD‐2 further increased the levels of both genes. These pieces of evidence implied that XD‐2 promotes longevity through endogenous signaling pathways rather than through the antioxidative activity alone. Taken all together, it may be concluded that XD‐2 is a promising antiageing agent.     

Anti-metastatic Effects on B16F10 Melanoma Cells of Extracts and Two Prenylated Xanthones Isolated from Maclura amboinensis Bl. Roots

Inhibitory effects of Maclura amboinenesis Bl, one plant used traditionally for the treatment of cancers, onmetastatic potential of highly metastatic B16F10 melanoma cells were investigated in vitro. Cell proliferationwas assessed using the MTT colorimetric assay. Details of metastatic capabilities including invasion, migrationand adhesion of B16F10 melanoma cells were examined by Boyden Chamber invasion and migration, scratchmotility and cell attachment assays, respectively. The results demonstrated that n-hexane and chloroformextracts exhibited potent anti-proliferative effects (p<0.01), whereas the methanol and aqueous extracts hadless pronounced effects after 24 h exposure. Bioactivity-guided chromatographic fractionation of both activen-hexane and chloroform extracts led to the isolation of two main prenylated xanthones and characterizationas macluraxanthone and gerontoxanthone-I, respectively, their structures being identified by comparison withthe spectral data. Interestingly, both exhibited potent effective effects. At non-toxic effective doses, n-hexaneand chloroform extracts (10 and 30 μg/ml) as well as macluraxanthone and gerontoxanthone-I (3 and 10μM) significantly inhibited B16F10 cell invasion, to a greater extent than 10 μM doxorubicin, while reducingmigration of cancer cells without cellular cytotoxicity. Moreover, exposure of B16F10 melanoma cells to highconcentrations of chloroform (30 μg/ml) and geratoxanthone-I (20 μM) for 24 h resulted in delayed adhesionand retarded colonization. As insights into mechanisms of action, typical morphological changes of apoptoticcells e.g. membrane blebbing, chromatin condensation, nuclear fragmentation, apoptotic bodies and loss ofadhesion as well as cell cycle arrest in the G1 phase with increase of sub-G1 cell proportions, detected by Hoechst33342 staining and flow cytometry were observed, suggesting DNA damage and subsequent apoptotic cell death.Taken together, our findings indicate for the first time that active n-hexane and chloroform extracts as well asmacluraxanthone and gerontoxanthone-I isolated from Maclura amboinensis Bl. roots affect multistep of cancermetastasis processes including proliferation, adhesion, invasion and migration, possibly through induction ofapoptosis of highly metastatic B16F10 melanoma cells. Based on these data, M. amboinensis Bl. represents apotential candidate novel chemopreventive and/or chemotherapeutic agent. Additionally, they also support itsethno-medicinal usage for cancer prevention and/or chemotherapy.     

黄牛木中的异戊烯基酮类化合物

目的 研究黄牛木茎60%乙醇提取物的化学成分.方法 运用多种色谱学方法对黄牛木茎60%乙醇提取物的化学成分进行分离,并根据光谱数据鉴定化合物的结构.结果 从该植物中分离得到5个(口山)酮类化合物,分别鉴定为1,7-二羟基-2-(3-甲基丁-2-烯基)-5"-羟基-6"-甲基-6"-(4-甲基戊-3-烯基)-4",5"-二氢吡喃(2",3":3,4)双苯吡酮(Ⅰ)、5,9-二羟基-8-甲氧基-2,2-二甲基-7-(3-甲基丁-2-烯基)-2H,6H-吡喃一[3,2.b]一双苯吡-6-酮(Ⅱ)、黄牛木(口山)酮A(Ⅲ)、4-(3',7'-二甲基辛-2',6'-二烯基)-1,3,5-三羟基-9H-双苯吡-9-酮(Ⅳ)和黄牛木酮A(Ⅴ).结论 化合物Ⅰ为新化合物,命名为越南黄牛木(口山)酮E(cracochinchinone E).化合物Ⅱ和Ⅳ为首次从黄牛木属植物中分离得到.     

Garcinia mangostana L.: a phytochemical and pharmacological review

Garcinia mangostana L. (mangosteen, Clusiaceae) has a long history of use as a medical plant, mostly in Southeast Asia. This is a review of the phytochemistry and pharmacology of mangosteen. Traditionally mangosteen is famous for its antiinflammatory properties and is used in the treatment of skin infections and wounds. Other applications include the therapy of various conditions such as dysentery, different urinary disorders, cystitis and gonorrhoea. This review highlights the development of this botanical drug into a widely used nutraceutical. Products derived from G. mangostana are now distributed increasingly all over the world. This has given rise to a concomitant increase in research on the phytochemical constituents and biological activity of mangosteen. Central to the biological activity of the species are xanthones which are reviewed in detail. A comprehensive assessment of the biological activities of individual xanthones as well as extracts of G. mangostana is included. In addition, its potential in terms of developing novel drug leads is assessed. Products containing its fruits are now sold widely as ‘liquid botanical supplements’, but evidence for the health benefits of these products is still lacking. As shown here, a serious weakness in our knowledge is the lack of clinical data and it is not yet clear to what extent the findings about pharmacological activities are of potential clinical relevance. Copyright © 2009 John Wiley & Sons, Ltd.     

Xanthone constituents of the fruits of Garcinia mangostana with anticomplement activity

Phytochemical investigation of a chloroform-soluble fraction of the freeze-dried fruits of Garcinia mangostana (Clusiaceace) with anticomplement activity in the classical pathway led to the identification of five known xanthones. The structures of these compounds were confirmed by interpretation of NMR and MS spectroscopic data. Of the isolates obtained, 1-isomangostin and garcinone E were found to be active constituents in the anticomplement assay used.     

In vitro antiprotozoal activity of some xanthones isolated from the roots of Andrographis paniculata

Four xanthones isolated from the roots of Andrographis paniculata were tested in vitro for antiprotozoal activity against Trypanosoma brucei brucei, Trypanosoma cruzi and Leishmania infantum. Compound TDR13011 (1,2-dihydroxy-6,8-dimethoxy-xanthone) showed good activity against T. b. brucei and L. infantum with a 50% inhibitory concentration (IC50) of 4.6 microg/ml and 8 microg/ml respectively. Xanthones from the roots of Andrographis paniculata exhibited promising anti-protozoal activity and these compounds could be chemically modified to obtain a more potent product.     

呫吨酮类化合物的药理作用研究进展

呫吨酮类化合物在自然界中广泛存在,它及其衍生物具有广泛的生理学和药理学活性,具有抗肿瘤、保护心血管、降低血糖、抗氧化、抗菌等药理作用,但很多药理作用机制尚处于研究探索阶段,从而使其药理活性及其与构型关系的研究倍受关注.收集国内外近几年来的有关文献,综述呫吨酮类化合物的药理研究进展.     

Advances in Isolation and Synthesis of Xanthone Derivatives

Xanthone and its derivatives occupy a large part of the family of natural polyphenolic compounds with various biological and pharmacological activities.In recent years(from 2006 to 2011),it was reported that 127 xanthones were discovered from plants and fungi using various modern separation methods including silica gel/polyamide column chromatography,HPLC,high-speed counter-current chromatography,high-performance centrifugal partition chromatography,etc.Since total synthesis and structure modification for xanthone and its derivatives have been given attention worldwide,we introduced the synthetic methods of xanthone skeletons as well.Unfortunately,to date,there are still weaknesses in current methods of separation and synthesis,which need to be improved.This review,to a certain extent,provides necessary foundation for the further research and development of medicines containing xanthone and its derivatives.     

元宝草｛口（左）山（右）｝酮成分的研究

 目的对元宝草的化学成分进行研究。方法利用硅胶、聚酰胺、Sephadex LH-20和大孔树脂柱色谱对化合物进行分离,并用光谱方法进行结构鉴定。结果分离鉴定了4个酮类成分:1-羟基-7-甲氧基酮(Ⅰ)、1,3,5-三羟基酮(Ⅱ)、1,3,6,7-四羟基酮(Ⅲ)和芒果苷(Ⅳ)。结论除化合物Ⅳ外,均为首次从该植物中分离得到。     

长梗喉毛花口山酮类化学成分的研究

目的:研究长梗喉毛花醋酸乙酯部位中(口山)酮类化学成分.方法:应用多种色谱技术进行分离纯化,根据化合物的理化性质和波谱数据鉴定化合物的结构.结果:从长梗喉毛花全草70%乙醇提取物的醋酸乙酯萃取部位对DL-半乳糖胺所致的肝损伤具有保肝作用的活性部位中分离得到9个(口山)酮类化合物,分别鉴定为1,8-二羟基-2,6-二甲氧基(口山)酮(1),8-羟基-1,2,6-三甲氧基(口山)酮(2),1,6,8-三羟基-2-甲氧基(口山)酮(3),1,8-二羟基-3,5-二甲氧基(口山)酮(4),1-羟基-3,5,8-三甲氧基(口山)酮(5),1-羟基-3,7-二甲氧基(口山)酮(6),1,2,6,8-四羟基(口山)酮(7),1,3,7-三羟基-4-甲氧基(口山)酮(8),6,8-二羟基-1,2-二甲氧基(口山)酮(9).结论:化合物6～9为首次从该属植物中分离得到.