Pugh N, Ross S A, ElSohly M A, Pasco D S
Department of Pharmacognosy, National Center for Natural Products Research, University of Mississippi, University, Mississippi 38677, USA.
J Agric Food Chem. 2001 Feb;49(2):1030-4. doi: 10.1021/jf001036d.
We have characterized a new immunostimulatory polysaccharide called Aloeride from commercial aloe vera (Aloe barbadensis) juice. Aloeride is between 4 and 7 million Da, and its glycosyl components include glucose (37.2%), galactose (23.9%), mannose (19.5%), and arabinose (10.3%). At 0.5 microg/mL Aloeride increased NF-kappa B directed luciferase expression in THP-1 human monocytic cells to levels 50% of those achieved by maximal concentrations (10 microg/mL) of LPS. Aloeride induced the expression of the mRNAs encoding IL-1beta and TNF-alpha to levels equal to those observed in cells maximally activated by LPS. Acemannan, the major carbohydrate component from aloe, used at 200 microg/mL in the macrophage assay resulted in negligible NF-kappa B activation. Analysis of acemannan and Aloeride using size-exclusion chromatography suggests that the low activity of acemannan is due to trace amounts of Aloeride. Although Aloeride comprises only 0.015% of the aloe juice dry weight, its potency for macrophage activation accounts fully for the activity of the crude juice.
我们已对一种名为Aloeride的新型免疫刺激多糖进行了特性分析，该多糖提取自市售库拉索芦荟（Aloe barbadensis）汁。Aloeride的分子量在400万至700万道尔顿之间，其糖基成分包括葡萄糖（37.2%）、半乳糖（23.9%）、甘露糖（19.5%）和阿拉伯糖（10.3%）。在浓度为0.5微克/毫升时，Aloeride可使THP-1人单核细胞中NF-κB指导的荧光素酶表达增加至最大浓度（10微克/毫升）LPS所达到水平的50%。Aloeride诱导编码IL-1β和TNF-α的mRNA表达至与LPS最大激活细胞中观察到的水平相当。在巨噬细胞试验中，芦荟的主要碳水化合物成分乙酰化甘露聚糖以200微克/毫升的浓度使用，导致NF-κB激活可忽略不计。使用尺寸排阻色谱法对乙酰化甘露聚糖和Aloeride进行分析表明，乙酰化甘露聚糖的低活性是由于痕量的Aloeride所致。尽管Aloeride仅占芦荟汁干重的0.015%，但其激活巨噬细胞的效力完全说明了粗汁的活性。
