铁皮石斛水提物通过激活SKN-1转录因子延长秀丽隐杆线虫寿命作用及机制研究

Effect and mechanism Dendrobium officinale water extract on prolongation of lifespan of Caenorhabditis elegans by activating SKN-1 transcription factor

中文关键词:  秀丽隐杆线虫  铁皮石斛  衰老:抗氧化

英文关键词:Caenorhabditis elegans  Dendrobium officinale  water extract  aging  antioxidant

中文摘要:

      目的 观察铁皮石斛水提物(Dendrobium officinale water extract, DOWE)延长秀丽隐杆线虫(Caenorhabditis elegans, C. elegans)寿命作用及可能机制。方法 将野生型(N2)线虫随机分为对照组、DOWE组[高剂量组(1000 μg/mL)、中剂量组(500 μg/mL)、低剂量组(250 μg/mL)], 观察DOWE冻干粉(最终生药量0.0376 g/g)对N2线虫寿命、运动和咽泵能力的影响; 通过检测氧化应激、热应激能力评估DOWE对N2线虫应激能力的影响, 检测活性氧(reactive oxygen species, ROS)、过氧化氢酶(catalase, CAT)、抗氧化基因等指标评价DOWE对N2线虫抗氧化能力的影响; 通过转基因线虫(LD1、CL2166)核转位情况及SKN-1转录因子相关基因表达情况来探究其在DOWE延长N2线虫寿命中的作用; 通过转基因线虫(LG348、LG357)荧光表达情况来探究DOWE延长N2线虫寿命所依赖的SKN-1转录因子类型; 通过检测有丝分裂原激活蛋白激酶(p38 mitogen activated protein kinase, p38 MAPK)信号通路相关基因表达情况探究DOWE通过激活SKN-1转录因子延长N2线虫寿命时, SKN-1转录因子的激活所依赖的上游通路。结果 DOWE中剂量组(500 μg/mL)可显著延长N2线虫的寿命, 平均延寿率达16.20%, 可显著提高运动、咽泵能力; 显著增强应激能力; 显著降低ROS水平和丙二醛(malondialdehyde, MDA)含量, 提高CAT、超氧化物歧化酶(superoxide disumutase, SOD)活性和谷胱甘肽(glutathione, GSH)含量, 同时上调SOD-5、SOD-3、CTL-1、CTL-2基因的表达水平; 对SKN-1缺陷型线虫EU1寿命及抗氧化应激能力无显著影响; DOWE显著升高了SKN-1c的核转位; DOWE显著升高p38 MAPK相关基因表达水平。结论 DOWE可能通过p38 MAPK激活肠道特异性转录因子SKN-1c, 增强抗氧化能力, 进而延长秀丽隐杆线虫健康寿命。

英文摘要:

      Objective To observe the effect and possible mechanism of Dendrobium officinale water extract (DOWE) on prolonging of lifespan of Caenorhabditis elegans (C. elegans). Methods Wild type (N2) nematodes were randomly divided into control and DOWE groups [ high dose group (1000 μg/mL), middle dose group (500 μg/mL), low dose group (250 μg/mL)], and the effects of DOWE on the lifespan, motility, and pharyngeal pumping ability of N2 nematodes were observed. The effects of DOWE on the stress ability of N2 nematodes were evaluated by detecting oxidative stress and heat stress ability, and the effects of DOWE on the antioxidant capacity of N2 nematodes were evaluated by detecting indicators such as reactive oxygen species (ROS), catalase (CAT), and antioxidant genes were invesgitated. The role of nuclear translocation of transgenic nematodes (LD1, CL2166) and expression of genes related to SKN-1 transcription factors in prolonging the lifespan of N2 nematodes was investigated. The SKN-1 transcription factor types relied on by DOWE to prolong the lifespan of N2 nematodes through the fluorescence expression of transgenic nematodes (LG348, LG357). The upstream pathway that DOWE relied on for activation of SKN-1 transcription factor when extending N2 nematode lifespan by activating SKN-1 transcription factor was examining by the expression profile of p38 mitogen activated protein kinase (p38 MAPK)-related genes. Results The DOWE medium dose group (500 μg/mL) could significantly prolong the lifespan of N2 nematodes, with an average lifespan extension rate of 16.20%, and could significantly improve motor and pharyngeal pumping abilities, significantly enhance stress capacity, significantly reduce ROS levels and malondialdehyde (MDA) content, increase CAT, superoxide disumutase (SOD) activity, and glutathione (GSH), content, while upregulating the expression levels of SOD-5, SOD-3, CTL-1, and CTL-2 genes. There was no significant effect on the lifespan and antioxidant stress capacity of SKN-1 deficient nematode EU1. DOWE significantly increased the nuclear translocation of SKN-1c. DOWE significantly increased the expression level of p38 MAPK related genes. Conclusion DOWE may enhance antioxidant capacity by activating p38 MAPK and activating intestinal specific transcription factor SKN-1c, thereby prolonging the healthy lifespan of C. elegans.