Transcriptomics of C. chinensis and E. ulmoides treated aged C. elegans

The nematode Caenorhabditis elegans was treated with extracts of the Traditional Chinese Medicine plants Cuscuta chinensis and Eucommia ulmoides from the L4 stage. In aged worms (on the 7th and 12th day of adulthood) different health parameters were determined. Besides the prolongation of lifespan, we found that C. chinensis improved the swimming behavior, pharyngeal pumping rate, stress resistance, mechanosensation and memory of aged C. elegans. Furthermore, the extract treatment reduced the autofluorescence, which is a known biomarker of ageing. Thus, we concluded that C. chinensis is an overall healthspan enhancer. In contrast, the E. ulmoides extract specifically enhanced the lifespan and stress resistance of aged C. elegans, but did not improve any other health aspect. To reveal the mechanism behind the healthspan enhancing effects of C. chinensis, the transcriptome of treated and untreated C. elegans on the 12th day of adulthood was analysed. For comparison purposes, E. ulmoides treated nematodes were included in the analysis. Overall design: Comparative gene expression profiling analysis of RNA-seq data for C. elegans treated with C. chinensis or E. ulmoides. DMSO treated nematodes were used as control. The treatment of nematodes took place from L4 until the 12th day of adulthood. Five biological repeats were prepared per treatment group.

本研究以秀丽隐杆线虫（Caenorhabditis elegans）为实验模型，于其L4发育期起，分别施以中草药植物菟丝子（Cuscuta chinensis）与杜仲（Eucommia ulmoides）的提取物。在成年第7天及第12天的衰老线虫中，研究人员测定了多项健康相关指标。除延长线虫寿命外，实验发现菟丝子提取物可改善衰老秀丽隐杆线虫的游泳行为、咽泵速率、应激抵抗能力、机械感觉及记忆功能。此外，该提取物处理可降低自体荧光（autofluorescence）——这是一种公认的衰老生物标志物。据此，本研究得出结论：菟丝子是一种全面的健康寿命（healthspan）增强剂。与之相反，杜仲提取物仅能特异性提升衰老秀丽隐杆线虫的寿命与应激抵抗能力，未对其他健康相关指标产生改善作用。为揭示菟丝子增强健康寿命的潜在分子机制，本研究对成年第12天时经提取物处理与未处理的秀丽隐杆线虫开展了转录组（transcriptome）分析；作为对照，本分析同时纳入了经杜仲提取物处理的线虫样本。总体实验设计：对经菟丝子或杜仲提取物处理的秀丽隐杆线虫的RNA测序数据进行比较基因表达谱分析。以二甲基亚砜（DMSO）处理的线虫作为空白对照。线虫的处理周期为从L4发育期直至成年第12天。每个处理组均设置5次生物学重复。