Oligosaccharides Regulating Cell Function

描述（申请人提供）：细胞凋亡是一个高度调控的细胞死亡过程。在分子水平上，细胞凋亡的去调控与包括癌症在内的多种人类疾病有关。低分子量果胶（LMP）是一种从植物细胞壁中提取的复杂碳水化合物，已被证明可诱导癌细胞凋亡，导致小鼠肿瘤体积减少。然而，由于LMP的复杂结构和样本异质性，解释这种观察到的凋亡机制的结构-功能关系仍然难以捉摸。因此，通过扩展酶和敏感分析技术与生物测定相结合的策略，开发了肝素/硫酸肝素样糖胺-的表征

DESCRIPTION (provided by applicant): Apoptosis is a highly regulated process of cell death. De-regulation of apoptosis at the molecular level has been implicated in a variety of human diseases, including cancer. Low molecular weight pectin (LMP), a complex carbohydrate derived from the wall of plant cells, has been shown to induce apoptosis in cancer cells leading to a reduction in tumor volume in mice. However, due to the complex structure and sample heterogeneity of LMP, a structure-function relationship to explain the mechanism underlying this observed apoptosis has remained elusive. Therefore, by extending the strategy of combining enzymes and sensitive analytical techniques with biological assays developed for the characterization of heparin/heparan sulfate-like glycosamino- glycans, the experiments proposed in this grant application are designed to produce more defined, biologically active LMP-derivatives. These LMP oligosaccharides will help provide clarity on the specific structure of LMP responsible for the polysaccharide's apoptosis-inducing effect. Building on the results of our initial experiments, the specific aims of this grant application are twofold: Specific Aim I will focus on expanding the methodology developed by our laboratory for the characterization glycosaminoglycans by developing the necessary enzymatic and analytical tools required for the degradation of LMP and the screening of the reaction products. Specific Aim II integrates the enzymatic and analytical tools developed in the first specific aim into a systematic protocol for the generation and purification of defined LMP derivatives that retain the ability to induce apoptosis in cells. As a whole, the research outlined in this grant application will yield LMP-derived oligosaccharides with lower molecular weight and less structural heterogeneity that are required for the further characterization of the cellular mechanism of action responsible for the induction of apoptosis. This grant application represents a high risk/high reward undertaking aimed at developing LMP as an effective treatment for of debilitating diseases caused by the deregulation of apoptosis, such as cancer.