Two new lignans fromLindera obtusiloba blume

Two new furanolignans (3, 5), together with three known lignans (1, 2, 4), were isolated from the stem of Lindera obtusiloba (Lauraceae). The structures of the compounds were determined as actifolin (1), pluviatilol (2), 5,6-dihydroxymatairesinol (3), (+)-syringaresinol (4), and (+)-9'-O-trans-feruloyl-5,5'-dimethoxylariciresinol (5) on the basis of physicochemical and spectroscopic evidences. Compounds 1, 2, 3, and 5 showed cytotoxicity against a small panel of human tumor cell lines with ED50 values of 3.40 to approximately 19.27 microg/ml.     

小花五味子中抗HIV活性的木脂素类化合物

目的：从小花五味子中发现具有抗HW活性的化学成分。方法：采用多种柱层析分离进行化合物的分离和纯化．通过波谱分析鉴定化合物的结构，化合物的抗HIV-1活性通过对HIV-1感染C8166细胞致细胞病变的抑制试验得到。结果：从小花五味子的茎藤部分分离得到了4个木脂素，分别鉴定为micrantherin A(1)，gomisin K3(2)，gomisin G(3)和vladinol F(4)。化舍物4具有显著的抗HIV-1活性，IC50=3.51μg／mL，选择指数为27、45。结论：化合物1为新的木脂素，化合物4的抗HIV-1活性值得进一步研究。     

Role of phytoestrogens in prevention and management of type 2 diabetes

Type 2 diabetes(T2D)has become a major public health threat across the globe.It has been widely acknowledged that diet plays an important role in the development and management of T2D.Phytoestrogens are polyphenols that are structurally similar to endogenous estrogen and have weak estrogenic properties.Emerging evidence from pre-clinical models has suggested that phytoestrogens may have anti-diabetic function via both estrogendependent and estrogen-independent pathways.In the current review,we have summarized the evidence linking two major types of phytoestrogens,isoflavones and lignans,and T2D from epidemiological studies and clinical trials.The cross-sectional and prospective cohort studies have reported inconsistent results,which may due to the large variations in different populations and measurement errors in dietary intakes.Long-term intervention studies using isoflavone supplements have reported potential beneficial effects on glycemic parameters in postmenopausal women,while results from short-term smallsize clinical trials are conflicting.Taken together,the current evidence from different study designs is complex and inconsistent.Although the widespread use of phytoestrogens could not be recommended yet,habitual consumption of phytoestrogens,particularly their intact food sources like soy and whole flaxseed,could be considered as a component of overall healthy dietary pattern for prevention and management of T2D.     

Selective Estrogen Receptor Modulation by Larrea nitida on MCF-7 Cell Proliferation and Immature Rat Uterus

Larrea nitida is a plant that belongs to the Zygophyllaceae family and is widely used in South America to treat inflammatory diseases, tumors and menstrual pain. However, its pharmacological activity remains unclear. In this study we evaluated the property of selective estrogen receptor modulator (SERM) of Larrea nitida extracts (LNE) as a phytoestrogen that can mimic, modulate or disrupt the actions of endogenous estrogens, depending on the tissue and relative amount of other SERMs. To investigate the property of SERM of LNE, we performed MCF-7 cell proliferation assays, estrogen response element (ERE)-luciferase reporter gene assay, human estrogen receptor (hER) binding assays and in vivo uterotrophic assay. To gain insight into the active principles, we performed a bioassay-guided analysis of LNE employing solvents of various polarities and using classical column chromatography, which yielded 16 fractions (LNs). LNE showed high binding affinities for hERα and hERβ with IC₅₀ values of 1.20 ×10⁻⁷ g/ml and 1.00×10⁻⁷ g/ml, respectively. LNE induced 17β-estradiol (E2)-induced MCF-7 cell proliferation, however, it reduced the proliferation in the presence of E2. Furthermore, LNE had an atrophic effect in the uterus of immature rats through reducing the expression level of progesterone receptor (PR) proteins. LN08 and LN10 had more potent affinities for binding on hER α and β than other fractions. Our results indicate that LNE had higher binding affinities for hERβ than hERα, and showed SERM properties in MCF-7 breast cancer cells and the rat uterus. LNE may be useful for the treatment of estrogen-related conditions, such as female cancers and menopause.     

A new flavonol galloylrhamnoside and a new lignan glucoside from the leaves of <Emphasis Type="Italic">Koelreuteria henryi</Emphasis> Dummer

A new flavonol galloylrhamnoside, kaempferol 3-O-(2″,3″-di-O-galloyl)-α-l-rhamnopyranoside, and a new lignan glycoside, hinokinin 7-O-β-d-glucopyranoside were isolated from the leaves of Koelreuteria henryi, along with 18 known compounds, including six flavonol glycosides (3–8), three lignans (9–11), four chlorophyll derivatives (12–15), two steroids (16, 17), and three aromatic compounds (18–20). The structures were determined on the basis of spectral analysis and chemical evidence. The scavenging effect of 1–8 and 20 on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was examined. Compounds 1, 5, 6, and 20 showed more potent activity than that of trolox.     

牛蒡子化学成分的研究

从牛蒡(Arctium lappa L.)子乙醚和丙酮提取物中,经硅胶柱层析,低压柱层析和制备性薄层层析分离到一个甾体化合物,胡萝卜甙(daucosterol,Ⅰ)和四个已知木脂素:牛蒡子甙元(arctigenin,Ⅱ)、牛蒡子甙(arctiin,Ⅲ)、罗汉松脂素(matairesinol,Ⅳ)和牛蒡酚F(lappaol F,Ⅴ)。一个新木脂素,命名为新牛蒡素乙(neoarctin B,Ⅵ)。根据光谱(UV,IR,¹H-NMR,¹³C-NMR,DEPT,2D-NMR和MS)分析,推定了其化学结构为式Ⅵ。     

Flaxseed and its components reduce metastasis after surgical excision of solid human breast tumor in nude mice

This study determined the effect of 10% flaxseed (FS) and its components, secoisolariciresinol diglycoside (SDG) and flaxseed oil (FO) alone or in combination (SDG+FO), on the metastasis and recurrence of human breast tumor after excision in nude mice. Mice were injected orthotopically with human breast cancer cells (MDA-MB-435) and fed basal diet (BD). When the tumors reached an average size of 110 mm(2) (0.9 g), surgical excisions were performed, and the mice were assigned to one of five diet groups for 7 weeks. The total incidence of metastasis was significantly lower in the FS, SDG, and SDG+FO groups. Reduced lung and lymph node metastases were observed in the FS and SDG+FO groups. In the FS and FO groups, a greater reduction in lung and total metastases was found when excised tumors were 0.9 g. There was no significant difference in tumor recurrence among groups. In conclusion, FS and its components inhibited tumor metastasis but not tumor recurrence after surgical excision of the primary tumor.     

Studies on chemical constituents from Ilex pubescens

Two new phenolic glycosides, ilexpubsides A and B, along with four known lignan glycosides were isolated from the roots of Ilex pubescens. By spectral evidence, the structures of the new compounds were elucidated as 4-O-β-D-[6'-O-(4'-O-β-D-glucopyranosylvanilloyl)glucopyranosyl] vanillic acid (1) and syringinic 6'-O-β-D-xylopyranoside (2). The known compounds were identified to be liriodendrin (3), (-)-olivil (4), tortoside A (5) and (+)-cyclo-olivil (6). All compounds were first isolated from Ilex pubescens.     

Lignans from the fruits of cornus kousa burg. and their cytotoxic effects on human cancer cell lines

The fruits of Cornus kousa Burg. were extracted with 80% aqueous MeOH, and the concentrated extract partitioned with EtOAc, n-BuOH and H2O. Six lignans were isolated from the EtOAc fraction through repeated silica gel, ODS and Sephadex LH-20 column chromatographies. From the physico-chemical data, including NMR, MS and IR, the chemical structures of the compounds were determined to be (+)-pinoresinol (1), (-)-balanophonin (2), (+)-laricresinol (3), erythro-guaiacylglycerol-beta-coniferyl aldehyde ether (4), threo-guaiacylglycerol-beta-coniferyl aldehyde ether (5) and dihydrodehydrodiconiferyl alcohol (6), which were isolated for the first time from this plant. Most of these compounds showed cytotoxicity against human colon carcinoma (HCT-116) and human hepatocellular carcinoma (HepG2) cell lines in vitro, with IC50 values ranging from 19.1 to 71.3 microg/mL.     

New lignan glycosides from Cupressus duclouxian (Cupessaceae)

From the branches and leaves of Cupressus duclouxiana two new lignan glycosides named cupressoside A (1) and cupressoside B (2), together with matairesinoside (3), dihydrodehydrodiconiferyl alcohol (4), dihydrodehydrodiconiferyl alcohol-9-O-α-l-rhamnopyranoside (5), dihydrodehydrodiconiferyl alcohol-4-O-α-l-rhamnopyranoside (6), ( ? )-isolariciresinol (7) and ( ? )-isolariciresinol-9-O-β-d-xylopyranoside (8), were isolated. The structures of these compounds were determined on the basis of their HR-FAB-MS, IR, UV, ¹H and ¹³C NMR (DEPT), and 2D NMR (HMQC, HMBC, COSY, NOESY) spectral data.