http://www.sciencenet.cn/htmlnews/2009/10/223847.shtm 研究发现敲除试验鼠某基因可助其抗衰老 英国研究人员在10月2日出版的新一期美国《科学》杂志上发表论文说,敲除实验鼠体内负责编码产生S6激酶1(一种核糖体蛋白)的基因,可以起到热量限制的效果,实验鼠患与衰老有关疾病的情况可大大减少,其中雌性实验鼠的寿命可延长约五分之一。 英国伦敦大学学院研究人员比较了基因敲除小鼠与普通实验鼠在出生后600天时的健康状况。这一年龄段相当于人类的中年阶段。 结果发现,雌性基因敲除实验鼠更精瘦,骨骼更强壮;尽管其食物摄取量增加,但身体脂肪含量却减少;它们并未出现中年阶段常见的胰岛素敏感度下降现象,因此不会患Ⅱ型糖尿病。在机动性实验中,它们的表现也好于普通实验鼠,这表明它们在平衡、力量及协调性方面优于后者。它们体内的T细胞也显得更年轻,说明其免疫水平高于同龄普通实验鼠。 此外,雌性基因敲除实验鼠平均存活了约950天,比普通实验鼠长约160天,寿命延长20%。雄性基因敲除实验鼠健康状况也好于普通实验鼠,不过其寿命与普通实验鼠并无太大差别。 研究人员表示,S6激酶1负责调节蛋白质翻译及细胞能量的代谢,抑制其表达可以起到热量限制的作用,这一实验再次证明,减少热量摄取对健康有益。 此前动物实验已多次证明,减少热量摄取有益于动物的健康。还有证据表明,尽管不清楚热量限制是否能延长人类寿命,但确实对人体健康有益。研究人员表示,这一研究为开发抑制人类衰老的药物提供了思路。 更多阅读 《科学》发表论文摘要(英文) Science 2 October 2009: Vol. 326. no. 5949, pp. 140 - 144 DOI: 10.1126/science.1177221 Ribosomal Protein S6 Kinase 1 Signaling Regulates Mammalian Life Span Colin Selman, 1 ,* Jennifer M. A. Tullet, 2 Daniela Wieser, 3 Elaine Irvine, 1 Steven J. Lingard, 1 Agharul I. Choudhury, 1 Marc Claret, 1 Hind Al-Qassab, 1 Danielle Carmignac, 4 Faruk Ramadani, 5 Angela Woods, 6 Iain C. A. Robinson, 4 Eugene Schuster, 3 Rachel L. Batterham, 1 Sara C. Kozma, 7 George Thomas, 7 David Carling, 6 Klaus Okkenhaug, 5 Janet M. Thornton, 3 Linda Partridge, 2 David Gems, 2 Dominic J. Withers 1 ,8 , Caloric restriction (CR) protects against aging and disease, but the mechanisms by which this affects mammalian life span are unclear. We show in mice that deletion of ribosomal S6 protein kinase 1 (S6K1), a component of the nutrient-responsive mTOR (mammalian target of rapamycin) signaling pathway, led to increased life span and resistance to age-related pathologies, such as bone, immune, and motor dysfunction and loss of insulin sensitivity. Deletion of S6K1 induced gene expression patterns similar to those seen in CR or with pharmacological activation of adenosine monophosphate (AMP)activated protein kinase (AMPK), a conserved regulator of the metabolic response to CR. Our results demonstrate that S6K1 influences healthy mammalian life-span and suggest that therapeutic manipulation of S6K1 and AMPK might mimic CR and could provide broad protection against diseases of aging. 1 Institute of Healthy Ageing, Centre for Diabetes and Endocrinology, Department of Medicine, University College London, London WC1E 6JJ, UK. 2 Institute of Healthy Ageing, Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, UK. 3 European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, UK. 4 Division of Molecular Neuroendocrinology, Medical Research Council National Institute for Medical Research, London NW7 1AA, UK. 5 Laboratory of Lymphocyte Signalling and Development, The Babraham Institute, Cambridge CB22 3AT, UK. 6 Cellular Stress Group, Medical Research Council Clinical Sciences Centre, Imperial College, London W12 0NN, UK. 7 Department of Cancer and Cell Biology, Genome Research Institute, University of Cincinnati, Cincinnati, OH 45237, USA. 8 Metabolic Signaling Group, Medical Research Council Clinical Sciences Centre, Imperial College, London W12 0NN, UK. * Present address: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, UK. To whom correspondence should be addressed. E-mail: d.withers@ucl.ac.uk