把皮膚細胞變成胰島細胞!

皮膚也能分泌胰島素, COOL! 加油, 張博士!!
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美國北卡羅來納大學的研究人員將來自人類皮膚的細胞轉化爲了能夠生成胰島素（用於治療糖尿病的激素）的細胞。研究者說，這個突破有朝一日能夠成爲治療甚至治癒上百萬糖尿病患者的良方。

這一方法包括將皮膚細胞改變爲多能幹細胞，即能夠增加其他重要或成熟細胞的種類，誘變其轉化爲具有特殊功能的細胞——本研究中是能夠分泌胰島素的細胞。最近的許多研究表明使用“遺傳因數”（能夠控制細胞中哪一個基因處於活躍狀態的特殊蛋白質）能夠使細胞還原爲多能狀態。在這一領域日本京都大學的Shinya Yamanaka博士的研究處於領先地位。

然而，美國紐卡斯爾大學（UNC）的研究是第一個宣佈用這種方法轉變的細胞能夠改變爲分泌胰島素的細胞。研究結果公佈在《生物化學雜誌》（Journal of Biological Chemistry）上。

研究者UNC的生物學教授張宜（音譯）博士說：“這不僅表明我們能夠改變皮膚細胞，而且我們也證明了這些細胞能夠被改變爲産生胰島素的細胞，這將可能有助於糖尿病的治療。”

美國糖尿病協會會長John Buse教授說：“當然這還需要進行大量的研究工作，但是這卻能夠爲所有糖尿病患者帶來希望。”

全世界大約有2400萬人患有糖尿病，當人體無法正確産生或使用胰島素的時候就會産生這種疾病。事實上，所有患有I型糖尿病的患者需要每天注射胰島素來控制他們的血糖水平。

新近研究提供了一種可能的長期治療方法——將能夠産生胰島素的細胞植入病人體內，十分令人期待。但是這個方法也面臨著挑戰，即匹配器官捐贈者的匱乏以及需要抑制病人的免疫系統。

張博士和其他研究者也提到了這些問題，這些細胞可以從病人的身上來獲得。

張博士與Buse合作從糖尿病患者身上收集皮膚樣本。他希望這些最新的實驗能夠有助於找到一種新的治療甚至治癒糖尿病的方法。（來源：中國公衆科技網隨風）

（《生物化學雜誌》（Journalof Biological Chemistry），doi：10.1074/jbc.M806597200，Keisuke Tateishi，Yi Zhang）

Public release date: 17-Sep-2008

Contact: Les Lang
llang@med.unc.edu

919-966-9366

University of North Carolina School of Medicine

UNC scientists turn human skin cells into insulin-producing cells

Yi Zhang, Ph.D., Howard Hughes Medical Institute investigator, professor of biochemistry and biophysics, University of North Carolina at Chapel Hill. Click here for more information.

CHAPEL HILL – Researchers at the

University of North Carolina at Chapel Hill School of Medicine have transformed cells from human skin into cells that produce insulin, the hormone used to treat diabetes.

The breakthrough may one day lead to new treatments or even a cure for the millions of people affected by the disease, researchers say.

The approach involves reprogramming skin cells into pluripotent stem cells, or cells that can give rise to any other fetal or adult cell type, and then inducing them to differentiate, or transform, into cells that perform a particular function – in this case, secreting insulin.

Several recent studies have shown that cells can be returned to pluripotent state using "defined factors" (specific proteins that control which genes are active in a cell), a technique pioneered by Dr. Shinya Yamanaka, a professor at Kyoto University in Japan.

However, the UNC study is the first to demonstrate that cells reprogrammed in this way can be coaxed to differentiate into insulin-secreting cells.

Results of the study are published online in the Journal of Biological Chemistry.

"Not only have we shown that we can reprogram skin cells, but we have also demonstrated that these reprogrammed cells can be differentiated into insulin-producing cells which hold great therapeutic potential for diabetes," said study lead author Yi Zhang, Ph.D., Howard Hughes Medical Institute investigator, professor of biochemistry and biophysics at UNC and member of the Lineberger Comprehensive Cancer Center.

"Of course, there are many years of additional studies that are required first, but this study provides hope for a cure for all patients with diabetes," said John Buse, M.D., Ph.D., president of the American Diabetes Association and professor and chief of the endocrinology division in the UNC School of Medicine's department of medicine.

About 24 million Americans suffer from diabetes, a disease that occurs when the body is unable to produce or use insulin properly. Virtually all patients with type I diabetes, the more severe
of the two types, must rely on daily injections of insulin to maintain their blood sugar levels.

Recent research exploring a possible long-term treatment – the transplantation of insulin-producing beta cells into patients – has yielded promising results. But this approach faces its own challenges, given the extreme shortage of matched organ donors and the need to suppress patients' immune systems.

The work by Zhang and other researchers could potentially address those problems, since insulin-producing cells could be made from diabetic patients' own reprogrammed cells.

Zhang is collaborating with Buse to obtain skin samples from diabetes patients. He said he hoped his current experiments will take this approach one step closer to a new treatment or even a cure for diabetes.

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The research was funded by the Howard Hughes Medical Institute and the National Institutes of Health. Study co-authors include postdoctoral fellows Keisuke Tateishi, M.D.; Jin He, Ph.D.; Olena Taranova, Ph.D.; Ana C. D'Alessio, Ph.D.; and graduate student Gaoyang Liang, all from
the UNC School of Medicine's department of biochemistry and biophysics.

Note: Zhang can be reached at yi_zhang@med.unc.edu.

School of Medicine contact: Les Lang, (919) 966-9366, llang@med.unc.edu

News Services contact: Patric Lane (919) 962-8596, patric_lane@unc.edu