Xiangpo Li

Publications (2)17.34 Total impact

• Article: Iron traffics in circulation bound to a siderocalin (Ngal)-catechol complex.

  Guanhu Bao, Matthew Clifton, Trisha M Hoette, Kiyoshi Mori, Shi-Xian Deng, Andong Qiu, Melanie Viltard, David Williams, Neal Paragas, Thomas Leete, [......], Xiangpo Li, Belinda Lee, Avtandil Kalandadze, Adam J Ratner, Juan Carlos Pizarro, Kai M Schmidt-Ott, Donald W Landry, Kenneth N Raymond, Roland K Strong, Jonathan Barasch
  [show abstract] [hide abstract]
  ABSTRACT: The lipocalins are secreted proteins that bind small organic molecules. Scn-Ngal (also known as neutrophil gelatinase associated lipocalin, siderocalin, lipocalin 2) sequesters bacterial iron chelators, called siderophores, and consequently blocks bacterial growth. However, Scn-Ngal is also prominently expressed in aseptic diseases, implying that it binds additional ligands and serves additional functions. Using chemical screens, crystallography and fluorescence methods, we report that Scn-Ngal binds iron together with a small metabolic product called catechol. The formation of the complex blocked the reactivity of iron and permitted its transport once introduced into circulation in vivo. Scn-Ngal then recycled its iron in endosomes by a pH-sensitive mechanism. As catechols derive from bacterial and mammalian metabolism of dietary compounds, the Scn-Ngal-catechol-Fe(III) complex represents an unforeseen microbial-host interaction, which mimics Scn-Ngal-siderophore interactions but instead traffics iron in aseptic tissues. These results identify an endogenous siderophore, which may link the disparate roles of Scn-Ngal in different diseases.
  Nature Chemical Biology 08/2010; 6(8):602-9. · 14.69 Impact Factor
• Article: Discovery of potent non-urea inhibitors of soluble epoxide hydrolase.

  Yuli Xie, Yidong Liu, Gangli Gong, Deborah H Smith, Fang Yan, Alison Rinderspacher, Yan Feng, Zhengxiang Zhu, Xiangpo Li, Shi-Xian Deng, Lars Branden, Dusica Vidović, Caty Chung, Stephan Schürer, Christophe Morisseau, Bruce D Hammock, Donald W Landry
  [show abstract] [hide abstract]
  ABSTRACT: Soluble epoxide hydrolase (sEH) is a novel target for the treatment of hypertension and vascular inflammation. A new class of potent non-urea sEH inhibitors was identified via high throughput screening (HTS) and chemical modification. IC(50)s of the most potent compounds range from micromolar to low nanomolar.
  Bioorganic & medicinal chemistry letters 05/2009; 19(8):2354-9. · 2.65 Impact Factor