Stress can turn hair gray -- and it's reversible, researchers find
研究人員發現-壓力可以導致頭發變白-頭發變白后還可以發生逆轉
Legend has it that Marie Antoinette's hair turned gray overnight just before her beheading in 1791.
根據傳說,瑪麗皇后(Marie Antoinette)在1971年被砍頭前,她的頭發在一夜之間由黑變白。
Though the legend is inaccurate -- hair that has already grown out of the follicle does not change color -- a new study from researchers at Columbia University Vagelos College of Physicians and Surgeons is the first to offer quantitative evidence linking psychological stress to graying hair in people.
盡管傳說-已經從毛囊中長出的頭發不會再變色-并不準確,由哥倫比亞大學Vagelos內科醫師和外科醫師學院的研究人員所開展的一項新研究首次提出了將心理壓力和頭發變白聯系在一起的量化證據。
And while it may seem intuitive that stress can accelerate graying, the researchers were surprised to discover that hair color can be restored when stress is eliminated, a finding that contrasts with a recent study in mice that suggested that stressed-induced gray hairs are permanent.
盡管從直覺上判斷壓力似乎會導致頭發加速變白,但是研究人員們驚奇地發現,當壓力消除后,頭發顏色還可以恢復到從前。這項研究結果與最近針對老鼠的一項研究結果相反。之前的研究表明,由于壓力所引起的頭發變白是永久性的。
The study, published June 22 in eLife, has broader significance than confirming age-old speculation about the effects of stress on hair color, says the study's senior author Martin Picard, PhD, associate professor of behavioral medicine (in psychiatry and neurology) at Columbia University Vagelos College of Physicians and Surgeons.
研究成果于6月22日在eLife上發表。研究資深作者哥倫比亞大學Vagelos內科醫師和外科醫師學院的Martin Picard,博士、行為醫學(精神病學和神經病學)助教表示,有關壓力對頭發顏色的影響這一推測由來已久,這項研究比證實這一推測具有更加廣闊的意義。
"Understanding the mechanisms that allow 'old' gray hairs to return to their 'young' pigmented states could yield new clues about the malleability of human aging in general and how it is influenced by stress," Picard says.
Picard表示:“了解‘年老’的白發重新變黑的原理可以產生新的線索,這些線索與人類變老總體的延展性以及壓力如何對變老產生影響有關。”
"Our data add to a growing body of evidence demonstrating that human aging is not a linear, fixed biological process but may, at least in part, be halted or even temporarily reversed."
“我們的數據和不斷增加的證據表明,人類變老并非是一個直線式的、固定的生物過程,相反,這一過程至少在某種程度上,可能中止或甚至臨時出現逆轉。”
Studying hair as an avenue to investigate aging
研究頭發是了解衰老的途徑
"Just as the rings in a tree trunk hold information about past decades in the life of a tree, our hair contains information about our biological history," Picard says. "When hairs are still under the skin as follicles, they are subject to the influence of stress hormones and other things happening in our mind and body. Once hairs grow out of the scalp, they harden and permanently crystallize these exposures into a stable form."
Picard表示:“正如樹干上的年輪代表著一棵大樹過去幾十年的生命軌跡,我們的頭發也包含了有關我們生物發展史方面的信息。當頭發還在皮膚內部以毛囊的形式存在時,他們會受到壓力荷爾蒙以及我們頭腦和身體中其他因素的影響。一旦頭發從頭皮中長出,頭發就會變硬并且會永久性地呈現出穩定的形態。”
Though people have long believed that psychological stress can accelerate gray hair, scientists have debated the connection due to the lack of sensitive methods that can precisely correlate times of stress with hair pigmentation at a single-follicle level.
盡管人們很早以來就認為心理壓力會加快頭發變白,但是由于缺乏可以精確地將壓力次數和某個單個毛囊中的頭發變白關聯在一起的敏感方法,所以科學家們一直對這一聯系有所爭論。
Splitting hairs to document hair pigmentation Ayelet Rosenberg, first author on the study and a student in Picard's laboratory, developed a new method for capturing highly detailed images of tiny slices of human hairs to quantify the extent of pigment loss (graying) in each of those slices. Each slice, about 1/20th of a millimeter wide, represents about an hour of hair growth.
為了將頭發分開并記錄頭發顏色的變化,Ayelet Rosenberg,研究的第一作者和Picard實驗室的學生,提出一種新的方法。這一方法可以捕獲到一小片頭發非常細微的圖像,以量化每片頭發失去顏色(變白)的程度。每片頭發大約20分之一毫米寬,代表了大約1個小時的頭發生長情況。
"If you use your eyes to look at a hair, it will seem like it's the same color throughout unless there is a major transition," Picard says. "Under a high-resolution scanner, you see small, subtle variations in color, and that's what we're measuring."
如果您用自己的眼睛去觀察一根頭發,除非這根頭發的顏色變化非常明顯,一般您會發現這根頭發似乎全都是一個顏色。但是,在高分辨率的掃描儀下,您會看到頭發的顏色有微小細微的變化,這就是我們正在測量的。
The researchers analyzed individual hairs from 14 volunteers. The results were compared with each volunteer's stress diary, in which individuals were asked to review their calendars and rate each week's level of stress.
研究人員對14名志愿者的單根頭發進行了分析。然后將分析結果與每位志愿者的壓力日志進行了對比。在對比過程中,志愿者被邀請回顧他們的日程并對每周的壓力程度進行打分。
The investigators immediately noticed that some gray hairs naturally regain their original color, which had never been quantitatively documented, Picard says.
Picard表示,調查人員立刻注意到,有些白發會自然變黑,而這一過程卻從未得到量化記錄。
When hairs were aligned with stress diaries by Shannon Rausser, second author on the paper and a student in Picard's laboratory, striking associations between stress and hair graying were revealed and, in some cases, a reversal of graying with the lifting of stress.
當Shannon Rausser將頭發與壓力日志保持一致后,Shannon發現了壓力和頭發變白之間存在明顯的聯系并且在某些情況下,白發會隨著壓力消失而重新變黑。
"There was one individual who went on vacation, and five hairs on that person's head reverted back to dark during the vacation, synchronized in time," Picard says.
Picard表示:“其中一位志愿者在度假,該名志愿者的5根頭發在度假期間又變回黑色,在時間上實現了同步。”
Blame the mind-mitochondria connection
思維-線粒體之間的聯系是導致頭發變白的罪魁禍首
To better understand how stress causes gray hair, the researchers also measured levels of thousands of proteins in the hairs and how protein levels changed over the length of each hair.
為了更好地了解壓力是如何導致頭發變白的,研究人員也測量了頭發中成千上萬個蛋白的水平以及蛋白水平是如何隨著每根頭發的長度而變化的。
Changes in 300 proteins occurred when hair color changed, and the researchers developed a mathematical model that suggests stress-induced changes in mitochondria may explain how stress turns hair gray.
頭發顏色發生變化后,300個蛋白也出現了變化。研究人員發明了一種數學模型。通過數學模型可以發現,線粒體中壓力所引起的變化可能解釋了壓力是如何讓頭發變白的。
"We often hear that the mitochondria are the powerhouses of the cell, but that's not the only role they play," Picard says. "Mitochondria are actually like little antennas inside the cell that respond to a number of different signals, including psychological stress."
Picard表示:“我們經常聽說線粒體是細胞的能量站,但是這并非是線粒體唯一的作用。線粒體實際上類似于細胞內的小天線,它們會對各種不同的信號,包括心理壓力做出反應。”
The mitochondria connection between stress and hair color differs from that discovered in a recent study of mice, which found that stress-induced graying was caused by an irreversible loss of stem cells in the hair follicle.
壓力和頭發顏色之間的線粒體連接與最近有關老鼠的研究結果有所不同。在之前的研究中, 研究發現壓力所導致的頭發變白是由于頭發毛囊中干細胞發生不可逆轉的損失所引起的。
"Our data show that graying is reversible in people, which implicates a different mechanism," says co-author Ralf Paus, PhD, professor of dermatology at the University of Miami Miller School of Medicine. "Mice have very different hair follicle biology, and this may be an instance where findings in mice don't translate well to people."
“我們的數據表明,頭發變白在人類中是可以逆轉的,這表明還存在一個不同的機制”,研究的共同作者Ralf Paul,博士、邁阿密米勒醫學院皮膚科教授表示。“老鼠的虹毛囊生理與人類完全不同,這也許就是為什么老鼠的研究結果并不會在人身上出現。”
Hair re-pigmentation only possible for some
可能僅有部分人的頭發會重新變黑
Reducing stress in your life is a good goal, but it won't necessarily turn your hair to a normal color.
減少生活中的壓力是一個不錯的目標,但是減少壓力并非一定會讓頭發變回到原來的顏色。
"Based on our mathematical modeling, we think hair needs to reach a threshold before it turns gray," Picard says. "In middle age, when the hair is near that threshold because of biological age and other factors, stress will push it over the threshold and it transitions to gray.
Picard表示:“根據我們的數學模型,我們認為頭發在變白之前需要達到某個閾值。在中年時,當頭發由于生理年齡和其他因素接近這一閾值時,壓力會迫使其突破閾值并開始變白。”
"But we don't think that reducing stress in a 70-year-old who's been gray for years will darken their hair or increasing stress in a 10-year-old will be enough to tip their hair over the gray threshold."
“盡管如此,我們并不認為,一位頭發已經白了數年的70歲老者在減少壓力后,其頭發會變黑,或者一位10歲的兒童在壓力增加到足夠程度后,其頭發會突破變白的閾值。”
來源:CNN , 編輯與整理:上海譯銳翻譯Susan