Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, CP 19046, Curitiba CEP 81.531-980, PR, Brazil.
Instituto de Pesquisa Pelé Pequeno Príncipe, Faculdades Pequeno Príncipe, Curitiba CEP 80250-060, PR, Brazil.
Int J Biol Macromol. 2020 Dec 15;165(Pt A):849-856. doi: 10.1016/j.ijbiomac.2020.09.218. Epub 2020 Sep 30.
Barks of trees of the genus Handroanthus are known for their antitumor activity, which is attributed to naphthoquinones. Another class of molecules that has shown antitumor activity are the polysaccharides, however those from Handroanthus barks have never been studied. Accordingly, the aim of this study was to extract polysaccharides from H. heptaphyllus and H. albus barks, to characterize them structurally and to evaluate their cytotoxic effects on the human colon and human breast cancer cell lines, Caco-2 and MCF-7, respectively. The polysaccharides were extracted with boiling water and fractionated by freeze-thawing process. The soluble polysaccharide fractions HHBSF and HABSF were characterized by monosaccharide composition, methylation and NMR analyses, and their effects on proliferation of Caco-2 and MCF-7 cells were evaluated using MTT cell viability assay. HHBSF and HABSF were mainly constituted of galactoglucomannan, type II arabinogalactan (AGII) and type I rhamnogalacturonan (RGI), however, only HABSF significantly inhibited the growth of MCF-7 (CC50 = 327 μg/mL) and Caco-2 (CC50 = 2258 μg/mL) cells. Differences in the fine structure and proportion of their polysaccharides, and maybe in the composition of associated phenolic compounds could explain the different effects of HHBSF and HABSF.
树木属的树皮已知具有抗肿瘤活性，这归因于萘醌。另一类具有抗肿瘤活性的分子是多糖，然而来自 Handroanthus 树皮的多糖从未被研究过。因此，本研究的目的是从 H. heptaphyllus 和 H. albus 树皮中提取多糖，对其进行结构表征，并评估它们对人结肠和人乳腺癌细胞系 Caco-2 和 MCF-7 的细胞毒性作用。多糖用沸水提取，并通过冻融过程进行分级。可溶多糖部分 HHBSF 和 HABSF 通过单糖组成、甲基化和 NMR 分析进行表征，并通过 MTT 细胞活力测定评估它们对 Caco-2 和 MCF-7 细胞增殖的影响。HHBSF 和 HABSF 主要由半乳糖甘露聚糖、II 型阿拉伯半乳糖聚糖（AGII）和 I 型鼠李半乳糖醛酸聚糖（RGI）组成，然而，只有 HABSF 显著抑制 MCF-7（CC50=327μg/mL）和 Caco-2（CC50=2258μg/mL）细胞的生长。它们的多糖的精细结构和比例的差异，以及可能与酚类化合物的组成的差异，可能解释了 HHBSF 和 HABSF 的不同作用。
