Ethanol extract of Kalopanax septemlobus leaf inhibits HepG2 human hepatocellular carcinoma cell proliferation via inducing cell cycle arrest at G_1 phase

Objective:To investigate the effects of an ethanol extract of Kalopanax septemlobus(Thunb.)Koidz.leaf(EEKS) on cell proliferation in human hepatocellular carcinoma cells and its mechanisms of action.Methods:Cells were treated with EEKS and subsequently analyzed for cell proliferation and flow cytometry analysis.Expressions of cell cycle regulators were determined by reverse transcriptase polymerase chain reaction analysis and Western blotting,and activation of eyclin-associaled kinases studied using kinase assays.Results:The EEKS suppressed cell proliferation in both HepG2 and Hep3 B cells,but showed a more sensitive anli-proliferative activity in HepG2 cells.Flow cytometry analysis revealed an association between the growth inhibitory effect of EEKS and with G_1 phase cell cycle arrest in HepG2 cells,along with the dephosphorylation of retinoblastoma protein(pRB) and enhanced binding of pRB with the E2 F transcription factor family proteins.Treatment with EEKS also increased the expression of cyclin-dependent kinase(CDK) inhibitors,such as p21WAF1/CIP1 and p27KIP1.without any noticeable changes in G_1 cyclins and CDKs(except for a slight decrease in CDK4).Treatment of HepG2 cells with EEKS also increased the binding of p21 and p27 with CDK4 and CDK6.which was paralleled by a marked decrease in the cyclin D- and cyclin E-associated kinase activities.Conclusions:Overall,our findings suggest that EEKS may be an effective treatment for liver cancer through suppression of cancer cell proliferation via G_1,cell cycle arrest Further studies arc required to identify the active compounds in EEKS.

Septemloside III: A Nonasaccharide Saponin from the Bark of Kalopanax septemlobus (Thunb.) Koidz.

A nonasaccharide saponin, new hederagenin saponin, had been isolated from the bark of Kalopanax septemlobus (Thunb.) Koidz., and its structure was elucidated by HRESI-MS, NMR experi- ments and chemical analyses as 3-O-β-D-xylopyranosyl-(1→4)-β-D-xylopyranosyl-(1→3)-α-L-rhamno- pyranosyl-(1→2)-α-L-arabinopyranosyl hederagenin 28-O-β-D-xylopyranosyl-(1→3)-β-D–xylopyra- nosyl-(1→2)-[α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)]-β-D-glucopyranoside.

Seedling Culture of Kalopanax septemlobus

Experiments on temperature-accelerated germination. seeding quantity, and optimum density of seedlings were made for Kalopanax septemlobus. The experimental results indicated that the seeds of kalopananx septemlobus had physiological dormancy because of unmature embryo and existence of inhibitory matter in the seed. Temperature-accelerated germination was a preferable and essential way to assure the germination. Seed dormancy could be overcome through accelerating germination. Firstly, warm treatment should be done, morphological maturity occurred, then, followed by lower temperature treatment, reaching physiological maturity, Seeding quantity, optimum density and the relations between density of seedlings and yield were studied.

濒危植物刺楸不定芽增殖与生根培养

本研究以刺楸愈伤组织诱导分化产生的不定芽为试验材料,探究不同条件下对刺楸组培苗不定芽增殖和生根的影响,获得最佳的刺楸离体培养条件。为建立完整的刺楸组培快繁体系提供理论基础和技术支持。结果表明:促进刺楸不定芽增殖的最佳激素浓度配比是6-BA 1.5 mg/L,NAA 0.10 mg/L。刺楸在增殖培养过程中会出现褐化情况,通过添加1.0 g/L聚乙烯吡咯烷酮PVP可有效减轻,相比硫代硫酸钠(Na2S2O3)和抗坏血酸(Vc)其抗褐化效果最优。生根培养试验中表明添加IBA 2.0 mg/L时生根率相对较高,为33.3%,此时根系分化较少且细弱。6-BA和吲哚丁酸IBA组合时不定根增殖效果最好,分化较多;当IBA浓度为2.0 mg/L时,不定根长而粗壮,增殖倍数最大为11.6;当6-BA浓度为0.3 mg/L时,生长良好,平均根长为12.3 mm。

不同因素对刺楸人工林生长的影响

对影响剌楸(Kalopanax septemlobus)人工林生长因素进行了分析,结果表明:剌楸人工林生长在山中腹、N坡、在坡度大于5°立地条件下,生长优势明显;土层厚度和土壤的养分含量对剌楸人工林的生长影响很大,试验表明,土层越厚,菅养物质丰富,有机质、全N全P、全K含量越高。剌楸人工林的生长与其它阔叶树种比较,生长处于优势;剌楸人工林随着林龄增长,受林分密度影响很大,适宜的密度不但能提高林分的优质、高产,而且能提高林分的生物量。