二氧化鈦奈米顆粒對發育中斑馬魚之行為研究

Behavioral effects of titanium dioxide nanoparticles on larval zebrafish (Danio rerio)

林純瑤(Chun-Yao Lin)

指導教授 ： 陳德豪 ； 曾美珍

國立屏東科技大學/農學院/水產養殖系所/碩士(2010年)

https://doi.org/10.6346/NPUST.2010.00157

摘要

奈米顆粒二氧化鈦是一種新興材料，可應用在藥妝及環保產品中，這些被製造的產品及副產品最終還是流入水中環境；傳統材料經奈米化後，使其顆粒變小，表面積增加，可能會造成水中生物之風險。而行為的改變，可用來評估魚類受到環境緊迫之影響，也可連結生化和生理過程，且提供環境汙染物對魚類之影響，影響層面可從個體層次到族群層次。本實驗以斑馬魚為模式物種，進行奈米顆粒二氧化鈦暴露，共六個處理組，分別為控制組, 0.1, 0.5, 1, 5 及10 mg/l，暴露後每12小時觀察其孵化率、畸形率，並在胚胎暴露第120小時後，進行游泳行為觀察，結果顯示其孵化率、存活率、畸形率皆無顯著差異，但在濃度為0.1、0.5、1 mg/l 時會造成斑馬魚仔魚平均泳速及活動力下降。第二部份奈米顆粒二氧化鈦抗氧化實驗則添加抗氧化劑之前驅物乙醯半胱氨酸50 μM (N-acetylcysteine, NAC)和抗氧化劑抑制物之穀胱甘肽合成酶抑制劑5 μM (buthionine sulfoximine, BSO)處理組，以探討奈米顆粒二氧化鈦是否會對生物體造成氧化緊迫反應，而行為結果顯示添加NAC與BSO，並不會影響其行為。再以啶橘染色分析斑馬魚仔魚之細胞凋亡，結果顯示細胞凋亡在各組間無顯著差異。此研究顯示奈米顆粒二氧化鈦除了氧化緊迫外可能還有其他因素參與了行為毒性，例如生理上反應、腦部神經受損等，其相關毒性還需往後更多研究加以證實。最後研究顯示，行為比其他傳統毒理學研究標的(例如：孵化率、活存率)更能敏感地偵測奈米顆粒二氧化鈦對斑馬魚之發育毒性。

關鍵字

奈米顆粒二氧化鈦 ； 斑馬魚 ； 行為 ； 啶橘染色 ； 氧化緊迫

並列摘要

Titanium dioxide nanoparticles (TiO2 NP) is a novel material that can be used in healthcare, cosmetics and environmental products. However, TiO2 NP would eventually flow into aquatic environment. Increased surface area of nanoparticles can potentially cause damage to aquatic lives. Behavior of fish provides connections to fish biochemistry and physiology processes, and can be a valuable tool to detect the influence of the environmental pressure on fishes. In addition, observing fish behaviors allow us to have a perspective on the influence of pollutants at the population level. In this study, fertilized zebrafish eggs were exposed to TiO2 NP (control, 0.1, 1.5, 1, 5 and 10 mg/l), and the hatching rate, mortality, malformation rate were observed every 12 hours. In addition, larval swimming ability was evaluated at 120 hours post fertilization. The result showed no significant difference in hatchability, survival, and malformation rate between groups, but TiO2 NP at 0.1, 0.5, 1 mg/l caused decreased average velocity and activity level of larval zebrafish. Co-exposure to either the glutathione precursor, N-acetylcysteine (NAC), or the glutathione synthesis inhibitor, buthionine sulfoximine (BSO), did not significantly alter the behavioral effects resulting from TiO2 NPs. Acridine orange staining of larvae showed no significant difference in apoptosis level between groups. Our data suggests that other factor(s) besides oxidative stress may contribute to the behavioral toxicity of TiO2 NPs. Our study also showed that the behavioral endpoints were more sensitive than the others (e.g., hatchability and survival) to detect toxicity of TiO2 NPs on developing fish.

並列關鍵字

titanium dioxide nanoparticles (TiO2 NP) ； zebrafish ； behavior ； acridine orange (AO) ； oxidative stress

參考文獻

Atchison, G.J., Henry, M.G., Sandheinrich, M.B., 1987. Effects of metals on fish behavior: a review. Environmental Biology of Fishes 18, 11-25.

Barakat, M.A., 2005. Adsorption behavior of copper and cyanide ions at TiO2-solution interface. Journal of Colloid and Interface Science 291, 345-352.

Beauvais, S.L., Jones, S.B., Brewer, S.K., Little, E.E., 2000. Physiological measures of neurotoxicity of diazinon and malathion to larval rainbow trout (Oncorhynchus mykiss) and their correlation with behavioral measures. Environmental Toxicology and Chemistry 19, 1875-1880.

Bjerselius, R., Lundstedt-Enkel, K., Olse´n, H., Mayer, I., Dimberg, K., 2001. Male goldfish reproductive behavior and physiology are severely affected by exogenous exposure to 17-estradiol. Aquatic Toxicology 53, 139-152.

Brewer, S.K., Little, E.E., DeLonay, A.J., Beauvais, S.L., Jones, S.B., Ellersieck, M.R., 2001. Behavioral Dysfunctions Correlate to Altered Physiology in Rainbow Trout (Oncorynchus mykiss) Exposed to Cholinesterase-Inhibiting Chemicals. Archives of Environmental Contamination and Toxicology 40, 70-76.