微量元素無機四價硒對秀麗隱桿線蟲 之有益及毒性效應探討

The Ameliorative and Toxic Responses of Selenite in the Nematode Caenorhabditis elegans

李汶軒(Wen-Hsuan Li)

指導教授 ： 廖秀娟

國立臺灣大學/生物資源暨農學院/生物環境系統工程學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.10573

摘要

硒對於哺乳類動物是一個已知的微量必需元素，並且對於細胞的反應相當重要。作為selenoprotein的成分之一，硒有其結構上和酵素作用的角色，具有抗氧化和癌症的化學保護能力。本研究利用秀麗隱桿線蟲作為模式生物用以了解硒是如何影響線蟲。首先透過建立dose-response去了解硒的毒性，發現硒對秀麗隱桿線蟲的致死濃度為2.785 mM。在0.01和0.05 μM低劑量硒的暴露下，硒具有加速秀麗隱桿線蟲發育和增強抵抗可抑制神經傳遞訊息化學物質所造成的癱瘓的能力。然而，在20 μM的較高劑量暴露下，硒反而會對於發育產生明顯延遲的效應，並對生育力、體長和壽命造成顯著的減少。此外本研究也發現，20 μM的硒會對於由aldicarb和levamisole此兩種藥物所產生的癱瘓有更為敏感的影響，但0.01 μM 的硒提供線蟲抵抗、保護此癱瘓的能力。本研究說明硒對於發育、生育力、壽命和神經系統具有有利(或保護)和不利的特質。

關鍵字

硒 ； 秀麗隱桿線蟲 ； 有利 ； 不利

並列摘要

Selenium (Se) is an universal essential trace element for mammals which is important for many cell processes. As a constituent of selenoproteins, Se has structural and enzymic roles and it has been recognized as an antioxidant and chemopreventive agent in cancer. In this study, we use a model organism Caenorhabditis elegans to understand how Se affects the nematodes. To understand the effects of Se(IV) on C. elegans, we established the dose response relationship and found that the LC50 of Se was 2.785mM. Low level of Se (0.01 and 0.05 μM) accelerated the development rate and enhanced the resistances to the paralysis caused by the chemicals related to cholinergic signaling. However, at the addition of 20 μM, Se caused significant delays of development and serious decreases in fertility, body sizes and life span. It caused the worms more hypersensitive to the paralysis caused by aldicarb and levamisole. But at the supplementation of 0.01 μM, Se could provide resistance to the paralysis. Our results showed that Se has both beneficial (or protective) and adverse properties on development, fertility, growth, lifespan, and nervous system.

並列關鍵字

Se ； Caenorhabditis elegans ； beneficial ； adverse

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