Science Focus ( issue 005 ) - page 7

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不 論古今中外，人們都在尋找青春之泉。隨著現代
科技進步，市場上自稱能夠逆轉衰老的產品種類更是不斷
倍增。預期未來數年，全球抗衰老產業將會成為一個規模
達US$ 3,460億的市場[1]。大部分消費者產品都是針對衰
老的徵狀或外觀變化，但科學家可能已有重大發現，了解衰
老過程的原理。
在對抗衰老之前，必須先了解何謂老化。生物功能其
實是繫於細胞分裂週期。然而，這個週期是有盡頭的，細
胞不能永遠分裂。位於染色體末端的端粒(telomeres)，
是一個細胞計時器，在每次細胞分裂後便會縮短。最終，
當端粒到達其長度下限時，細胞不能再分裂，就會失去原
有的功能，隨之而來的是衰退和老化。在2014年，科學家
Timothy M. Tucey和Victoria Lundblad發表了一項研
究，是關於控制端粒縮短機制的細胞「開關」[2]。該機制所
涉及的端粒酶(telomerase)，擁有重建端粒的能力。他們
發現端粒酶可以開啟和關閉，能夠延緩端粒的縮短過程，實
現持續的組織再生[2]。利用這種技術，便有可能讓老年人
的重要器官再生，與及發展針對老化相關疾病的新療法。
目前抗衰老「療法」可分為兩大類-分別為體內補充
和外觀修復。前者是指聲稱可以加速代謝率的激素替代療
法。然而，迄今沒有任何正式研究，證明激素替代療法可
以延長壽命或預防老化所致的虛弱[3]。相反，某些研究指
出，這類治療可能會引起有害的副作用，例如：增加罹患乳
腺癌、心血管疾病和中風的風險[4]。另一方
面，外觀修復法主要是指整形外科手
術或護膚產品，處理外貌的老化，須
要重複療程方能維持暫時性的效
果。根據消費者報告(Consumer
Repor ts)，最有效的面霜僅僅令
皺紋深度減少10％，顯示這類產品
的功效極為有限[5]。
要成功逆轉衰老，路途仍很遙遠。托馬斯．蘭度教授就
指出，通過小鼠等模型所得出的老化研究結果，未必可以
反映較為複雜的動物的反應（請參閱第22頁的專訪）。實
際上，越是複雜的生物體，就越難逆轉老齡過程。不過，這
類研究無疑是朝著正確方向邁出了一步。
References
[1] Antiaging Products and Services: The Global Market (2013). BBC Research. Retrieved from http://www.bccresearch.com/market-
research/healthcare/antiaging-products-services-hlc060b.html.
[2] Tucey, T. M., Lundblad, V., Regulated assembly and disassembly of the yeast telomerase quaternary complex (2014). Genes &
Development. DOI: 10.1101/gad.246256.114
[3] Can We Prevent Aging? (2010). National Institute on Aging. Retrieved from http://www.nia.nih.gov/sites/default/files/can_we_prevent_
aging_0.pdf
[4] U.S. Women’s Health Initiative (2010). Women’s Health Initiative Clinical Trial and Observational Study. Retrieved from http://www.ncbi.
nlm.nih.gov/projects/gap/cgi-bin/study.cgi?study_id=phs000200.v1.p1
[5]Consumer Reports Tests Wrinkle Creams for the First Time (2007). Consumer Reports. Retrieved from http://www.suncitydermatology.com/
wp-content/themes/thesis_185/custom/consume-reports-creams.pdf
At the Biotechnology Research Institute
of HKUST, which was established through a
generous donation from The Hong Kong Jockey
Club, researchers had successfully identified
a telomerase activator TAT-2 from traditional
Chinese medicines. The activator has been
re-named as TA-65 and is now being used in
a health maintenance programme by a US
company.
由香港賽馬會捐助而成立的科技大學生物技術研
究所，其研究人員從傳統中藥提取物中首次發現了端
粒酶激活劑TAT-2。這活化劑目前被改名為TA-65，正
由一間美國公司用於健康維保計劃。
other hand, appearance restorers mainly consist
of cosmetic treatments or skin care products,
dealing with the cosmetic aging and requiring
repeated treatments to maintain temporar y
effects. According to Consumer Reports, the best
per forming cream only brought about a 10%
reduction in the depths of wrinkles, suggesting that
these types of products are extremely limited in
their effectiveness [5].
Much work still needs to be done to make
significant contributions to reverse aging. Prof.
Thomas A. Rando pointed out that models used to
investigate aging, such as laboratory mice, may
not reflect the same results in complex animals
(read his interview on Page 22). In fact, the more
complex the biological organism, the less likely
age reversal would work. Studies like this, however
undoubtedly take a step in the right direction.