| 查看: 269 | 回复: 2 | ||
| 当前主题已经存档。 | ||
xiaoyue1199兑换贵宾
第三军团情报局长
|
[交流]
【资源】心理压力会让你的头发变白吗（已搜索无重复）
|
|
|
FASEB J：心理压力会让你的头发变白吗 最终决定头发变化的因素还是基因 当头上开始出现白发时，我们总认为这是压力所导致的——这些压力来自高强度的工作、疾病、甚至是不听话的孩子。 但心理压力致使头发变白的说法只不过是民间的传言，很多科学研究都不支持这个理论。然而，人们还是不免胡乱猜测。就在上周，不论是纽约时报还是其他媒体，人们把目光聚集在了美国总统奥巴马那已经花白的两鬓上，认为这从生理角度证明了总统是这个世界上压力最大的职业之一。 那么头发变白到底是什么原因呢？ 上个月，欧洲的一组研究人员在这方面取得了一些突破性进展。他们长期研究一种因基因缺失而导致的疾病——白斑病，俗称白癜风。这是一种原发性的皮肤色素脱失症，患处皮肤呈白色。而且由于白斑病患者体内过氧化氢酶的水平较低，而过氧化氢酶的主要作用是分解过氧化氢，所以患者表皮内的过氧化氢含量过多，对黑素细胞会产生损伤作用。这项研究的相关情况已经刊登在上个月的《美国实验生物学联合会会刊》（FASEB J）中。 http://www.fasebj.org/cgi/conten ... ;resourcetype=HWCIT |
回复此楼
xiaoyue1199
兑换贵宾
第三军团情报局长
- 应助: 1 (幼儿园)
- 金币: 3674.4
- 散金: 2164
- 红花: 2
- 帖子: 1348
- 在线: 630小时
- 虫号: 443065
- 注册: 2007-10-27
- 专业: 应用高分子化学与物理
|
Senile hair graying: H2O2-mediated oxidative stress affects human hair color by blunting methionine sulfoxide repair J. M. Wood, H. Decker, H. Hartmann, B. Chavan, H. Rokos, J. D. Spencer, S. Hasse, M. J. Thornton, M. Shalbaf, R. Paus, and K. U. Schallreuter E-mail contact: k.schallreuter@bradford.ac.uk ABSTRACT: Senile graying of human hair has been the subject of intense research since ancient times. Reactive oxygen species have been implicated in hair follicle melanocyte apoptosis and DNA damage. Here we show for the first time by FT-Raman spectroscopy in vivo that human gray/white scalp hair shafts accumulate hydrogen peroxide (H2O2) in millimolar concentrations. Moreover, we demonstrate almost absent catalase and methionine sulfoxide reductase A and B protein expression via immunofluorescence and Western blot in association with a functional loss of methionine sulfoxide (Met-S=O) repair in the entire gray hair follicle. Accordingly, Met-S=O formation of Met residues, including Met 374 in the active site of tyrosinase, the key enzyme in melanogenesis, limits enzyme functionality, as evidenced by FT-Raman spectroscopy, computer simulation, and enzyme kinetics, which leads to gradual loss of hair color. Notably, under in vitro conditions, Met oxidation can be prevented by L-methionine. In summary, our data feed the long-voiced, but insufficiently proven, concept of H2O2-induced oxidative damage in the entire human hair follicle, inclusive of the hair shaft, as a key element in senile hair graying, which does not exclusively affect follicle melanocytes. This new insight could open new strategies for intervention and reversal of the hair graying process.—Wood, J. M., Decker, H., Hartmann, H., Chavan, B., Rokos, H., Spencer, J. D., Hasse, S., Thornton, M. J., Shalbaf, M., Paus, R., Schallreuter, K. U. Senile hair graying: H2O2-mediated oxidative stress affects human hair color by blunting methionine sulfoxide repair. |
2楼2009-05-11 09:12:50
3楼2009-05-11 15:01:55
10