title: Black tea increased survival of Caenorhabditis elegans under stress.
abstract: The present study examined the effects of black tea (Camellia sinensis) extracts (BTE) in Caenorhabditis elegans under various abiotic stressors. Results showed BTE increased nematode resistance to osmosis, heat, and UV irradiation treatments. However, BTE could not increase nematodes' lifespan under normal culture conditions and MnCl2-induced toxicity at concentrations we used. Further studies showed that BTE decreased reactive oxygen species and up-regulated some antioxidant enzymes, including GSH-PX, and genes, such as gsh-px and sod-3. However, only a slight extension in mev-1 mutants mean lifespan was observed without significance. These results indicated that the antioxidant activity of BTE might be necessary but not sufficient to protect against aging to C. elegans. Moreover, BTE increased the mRNA level of stress-response genes such as sir-2.1 and sek-1. Our finding demonstrated BTE might increase heat and UV stress resistance in a sir.2.1-dependent manner. Taken together, BTE enhanced stress resistance with multiple mechanisms in C. elegans.
authors.affiliation: Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University , Changsha, Hunan 410128, China.
authors.forename: Li-Gui
authors.initials: LG
authors.lastname: Xiong
authors.forename: Jian-An
authors.initials: JA
authors.lastname: Huang
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.forename: Peng-Hui
authors.initials: PH
authors.lastname: Yu
authors.forename: Zhe
authors.initials: Z
authors.lastname: Xiong
authors.forename: Jian-Wei
authors.initials: JW
authors.lastname: Zhang
authors.forename: Yu-Shun
authors.initials: YS
authors.lastname: Gong
authors.forename: Zhong-Hua
authors.initials: ZH
authors.lastname: Liu
authors.forename: Jin-Hua
authors.initials: JH
authors.lastname: Chen
mesh_terms: D000375:Aging / Q000235:genetics / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D017173:Caenorhabditis elegans / Q000235:genetics / Q000254:growth & development / Q000502:physiology* / Q000528:radiation effects; D028241:Camellia sinensis / Q000378:metabolism*; D006358:Hot Temperature; D028321:Plant Preparations / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013312:Stress, Physiological; D013662:Tea; D014466:Ultraviolet Rays
chemical_list: D000975:Antioxidants; D028321:Plant Preparations; D017382:Reactive Oxygen Species; D013662:Tea
keywords: Caenorhabditis elegans; black tea; black tea extracts; stress resistance; survival