METHODS: This study subjected the ethanolic extract to enzymatic assays to quantify the phytochemical content (phenolics, flavonoids, and anthraquinones) and its radical scavenging and iron-reducing capacities. Also, the phytoconstituents and major phenolic compounds present in the extract\'s subfractions were identified by GC-MS, HPLC, and NMR. Human cancer (MCF-7, PC-3, HT-29) and normal colon (CoN) cell lines were treated with different concentrations of K. pinnata leaf ethanolic extract, and the changes in cell proliferation (sulforhodamine B assay), caspases activity (FITC-VAD-FMK reporter), mitochondrial membrane potential (MMP, rhodamine 123 assay), chromatin condensation/fragmentation (Hoechst 33342 stain), and ROS generation (DCFH2 probe assay) were assessed.
RESULTS: The results showed that the K. pinnata leaf ethanolic extract is rich in phytoconstituents with therapeutic potential, including phenols (quercetin and kaempferol), flavonoids, fatty acid esters (34.6% of the total composition), 1- triacontanol and sterols (ergosterol and stigmasterol, 15.4% of the total composition); however, it presents a poor content of antioxidant molecules (IC50 = 27.6 mg/mL for H2O2 scavenging activity vs. 2.86 mg/mL in the case of Trolox). Notably, the extract inhibited cell proliferation and reduced MMP in all human cell lines tested but showed selectivity for HT-29 colon cancer cells compared to CoN normal cells (SI = 8.4). Furthermore, ROS generation, caspase activity, and chromatin condensation/fragmentation were augmented significantly in cancer-derived cell lines, indicating a selective cytotoxic effect.
CONCLUSIONS: These findings reveal that the K. pinnata leaf ethanolic extract contains several bioactive molecules with therapeutic potential, capable of displaying selective cytotoxicity in different human cancer cell lines.
方法:本研究对乙醇提取物进行酶测定,以定量植物化学物质含量(酚类,黄酮类化合物,和蒽醌)及其自由基清除和铁还原能力。此外,通过GC-MS鉴定了提取物亚组分中存在的植物成分和主要酚类化合物,HPLC,和NMR。用不同浓度的K.pinnata叶乙醇提取物处理人类癌症(MCF-7,PC-3,HT-29)和正常结肠(CoN)细胞系,和细胞增殖的变化(磺罗丹明B测定),胱天蛋白酶活性(FITC-VAD-FMK报告基因),线粒体膜电位(MMP,罗丹明123测定),染色质凝聚/碎片化(Hoechst33342染色),和ROS产生(DCFH2探针测定)被评估。
结果:结果表明,山葵叶乙醇提取物富含具有治疗潜力的植物成分,包括酚类(槲皮素和山奈酚),黄酮类化合物,脂肪酸酯(占总组成的34.6%),1-三十烷醇和甾醇(麦角甾醇和豆甾醇,占总成分的15.4%);然而,它呈现的抗氧化剂分子含量低(IC50=27.6mg/mL的H2O2清除活性与在Trolox的情况下为2.86mg/mL)。值得注意的是,提取物在所有测试的人细胞系中抑制细胞增殖并降低MMP,但与CoN正常细胞相比显示对HT-29结肠癌细胞的选择性(SI=8.4)。此外,ROS生成,caspase活性,在癌症来源的细胞系中,染色质凝聚/片段显着增强,表明选择性细胞毒性作用。
结论:这些发现表明,山葵叶乙醇提取物含有几种具有治疗潜力的生物活性分子,能够在不同的人类癌细胞系中显示选择性细胞毒性。