Dephosphorylation and biodistribution of 1-<sup>13</sup>C-phospholactate<i>in vivo</i>
作者:Roman V. Shchepin、Wellington Pham、Eduard Y. Chekmenev
DOI:10.1002/jlcr.3207
日期:2014.6.30
Here, we present a new approach for the delivery of a metabolic contrast agent for in vivo molecular imaging. The use of a phosphate-protecting group that facilitates parahydrogen-induced polarization of 1-13C-phospholactate potentially enables the in vivo administration of a hydrogenated hyperpolarized adduct. When injected, nonhyperpolarized 1-13C-phospholactate is retained in the vasculature during its metabolic conversion to 1-13C-lactate by blood phosphatases as demonstrated here using a mucin 1 mouse model of breast cancer and ex vivo high-resolution 13C NMR. This multisecond process is a suitable mechanism for the delivery of relatively short-lived 13C and potentially 15N hyperpolarized contrast agents using –OH phosphorylated small molecules, which is demonstrated here for the first time as an example of 1-13C-phospholactate. Through this approach, dl-1-13C-lactate is taken up by tissues and organs including the liver, kidneys, brain, heart, and tumors according to a timescale amenable to hyperpolarized magnetic resonance imaging.
在这里,我们提出了一种为体内分子成像提供代谢造影剂的新方法。使用磷酸盐保护基团可促进 1-13C 磷脂酰半乳糖的对氢诱导极化,从而实现氢化超极化加合物的体内给药。注射后,非超极化的 1-13C 磷脂酰乳酸盐在血液磷酸酶将其代谢转化为 1-13C 乳酸盐的过程中会保留在血管中,本文使用乳腺癌粘蛋白 1 小鼠模型和体内外高分辨率 13C NMR 证实了这一点。这种多秒过程是利用-OH磷酸化小分子递送相对短效的 13C 和潜在的 15N 超极化造影剂的合适机制,本文首次以 1-13C 磷脂酰乳酸盐为例进行了展示。通过这种方法,dl-1-13C-乳酸可被组织和器官吸收,包括肝脏、肾脏、大脑、心脏和肿瘤,其时间尺度适合超极化磁共振成像。