提子皮抗衰老

人類自古以來對「長生不老」趨之若鶩，時至今日「抗衰老」仍是不少人窮一生希望掌握的秘密，香港大學醫學院生物化學系教授周中軍的團隊正向着謎底邁進，他們發現提子皮所含的物質「白藜蘆醇」可刺激動物體內的「長壽基因」，並研發出治療早老症的藥物，已在動物實驗證實可延長近三成壽命，去年起更開始於內地安排病人參與試驗。憑藉對衰老研究領域的貢獻，周中軍獲得本年度裘槎優秀科研者獎。

早老症屬非常罕見的疾病，病發率約四百萬分之一，患者一般在六個月大已開始衰老，普遍不能活過十三歲。周中軍指，此病並非遺傳病，而是由基因突變而起。他在過去十多年的研究中發現，提子等水果表皮所含的物質「白藜蘆醇」可刺激動物體內的「長壽基因」SIRT1，保護幹細胞以達致延長早老症動物的壽命。

去年底開展臨床試驗

有關研究過去一直利用老鼠進行實驗，發現把「白藜蘆醇」用於患有早老症的老鼠，可延長其壽命兩至三成；若用於正常的老鼠，牠們的毛髮也會明顯變得有光澤，而且白毛比較少，不過就未見有延長壽命的效果，亦未能肯定可以延緩衰老。

研究團隊去年底首次於內地開展臨床試驗，現時有八名由兩歲至十六歲的早老症患者正試用新藥，他們會先接受三個月的觀察期，然後按體重服食不同劑量的新藥物，持續六個月，再監察藥效。八名病人已開始服藥一個月，尚待結果。

周中軍強調，「長壽基因」SIRT1絕非愈活躍愈好，過去有研究發現，如果能夠令動物體內的「長壽基因」增加至原本的兩倍，抗衰老效果最理想；但如果十倍的「長壽基因」被激活，反而有機會破壞其他非幹細胞的正常細胞。因此，究竟要服食或攝取多少分量的「白藜蘆醇」，才可令SIRT1增兩倍，以及應用在人體的效果，仍待更多研究確定。

現時坊間有部分加入「白藜蘆醇」的營養補充劑已獲美國食品及藥物管理局（FDA）批准出售。周中軍笑言自己偶爾也有服用這些補充劑，但目前仍未能以科學方法證實這些產品的抗衰老成效，他期望日後可獲更多資源作相關的深入研究。

Professor Zhongjun ZHOU (HKU), Professor, Department of Biochemistry, Li Ka Shing Faculty of Medicine. Professor Zhou is an internationally recognised expert on laminopathy-based premature aging and extracellular matrix. His major research field is bone development, blood vessel development and aging. His research focuses on premature aging and aging-associated diseases, as well as extracellular matrix. Professor Zhou and his team identified prelamin A as an in vivo substrate for metalloproteinase Zmpste24 through a genetic approach and explained how Lamin A’s abnoramality influences development and aging. His team demonstrated lamin A activates longevity protein SIRT1 to maintain the stem cell potency. He revealed for the first time that mutation in nuclear structural protein lamin A compromises DNA repair, which contributes to accelerated aging in Hutchinson-Gilford Progeria Syndrome. His work provides important insights into the molecular mechanisms underlying Hutchinson-Gilford Progeria Syndrome (HGPS). This has an important implication in normal aging and aging–related human degenerative disorders.

2015 croucher award

Activation of SIRT1 by Resveratrol requires lamin A

resveratrol rescues SIRT dependent Adult Stem cell decline

another link

Dr John Pezzuto: cancer chemopreventive action of resveratrol

Genes and Development: Structural basis for allosteric, substratedependent stimulation of SIRT1 activity by resveratrol and here in English and in pdf

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Scythians 斯泰基塞種西古提人

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