美国科学家近日研究发现，“婴儿”脂肪细胞（即未成熟脂肪细胞）潜伏在血管壁中，等待着过剩的卡路里帮助它们长成成年“魔鬼”，增加人们的体重。这是首次发现这类细胞的“巢穴”，该结果有助于指导将来发现阻止这些细胞制造多余脂肪的方法，并有望在其它医疗实践上得到应用。相关论文9月18日在线发表于《科学》（Science）杂志上。
通常情况下，祖细胞会在多种情况下制造新的脂肪细胞，比如当年幼身体生长并需要形成脂肪细胞的时候。它们对于维持体重的稳定也很必要，老的脂肪细胞死去，必须由新的进行补充，然而，当热量摄取过剩时，不仅现有脂肪细胞会变大以储存更多脂肪，祖细胞也会制造新的脂肪细胞。
美国德州大学西南医学中心的Jonathan Graff和同事利用遗传手段令小鼠干细胞发荧光，据此发现这些未成熟脂肪细胞位于穿过脂肪组织的血管壁中。Graff说：“它们并不是附着在血管壁上，而是成为了血管壁的一部分。”他认为，这种“安排”自有用意，它能够使未成熟脂肪细胞对餐后出现在血液中的葡萄糖等营养元素作出响应。当感受到过剩热量摄取时，它们就会从血管壁中凸现出来，成长为成熟脂肪细胞。这种安排确保了它们位于其它脂肪细胞间的适当位置。
Graff表示：“此次发现具有理论和实践的双重意义。鉴别出脂肪细胞祖细胞并发现它们的位置，为我们提供了令人兴奋的治疗机会。我们也许能够开发出新的治疗手段，来帮助肥胖、糖尿病以及其它代谢问题的患者。”（生物谷Bioon.com）
生物谷推荐原始出处：
Science，DOI: 10.1126/science.1156232，Wei Tang，Jonathan M. Graff
White Fat Progenitor Cells Reside in the Adipose Vasculature
Wei Tang 1, Daniel Zeve 1, Jaemyoung Suh 1, Darko Bosnakovski 1, Michael Kyba 1, Bob Hammer 2, Michelle D. Tallquist 2, Jonathan M. Graff 3*
1 Department of Developmental Biology, University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, NB5.118, Dallas, TX 75390–9133, USA.
2 Department of Molecular Biology, University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, NB5.118, Dallas, TX 75390–9133, USA.
3 Department of Developmental Biology, University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, NB5.118, Dallas, TX 75390–9133, USA.; Department of Molecular Biology, University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, NB5.118, Dallas, TX 75390–9133, USA.; Department of Internal Medicine, University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, NB5.118, Dallas, TX 75390–9133, USA.
White adipose (fat) tissues regulate metabolism, reproduction and lifespan. Adipocytes form throughout life, with the most marked expansion of the lineage occurring during the postnatal period. Adipocytes develop in coordination with the vasculature, but the identity and location of white adipocyte progenitor cells in vivo are unknown. We used genetically marked mice to isolate proliferating and renewing adipogenic progenitors. We find that most adipocytes descend from a pool of these proliferating progenitors that are already committed either prenatally or early in postnatal life. These progenitors reside in the mural cell compartment of the adipose vasculature but not in the vasculature of other tissues. Thus, the adipose vasculature appears to function as a progenitor niche and may provide signals for adipocyte development.
