Mitochondrial-targeted and Near-infrared Fluorescent Probe for Bioimaging and Evaluating Monoamine Oxidase A Activity in Hepatic Fibrosis.

Monoamine Oxidase A (MAO-A) is a promising diagnostic marker for cancer, depression, parkinson's disease and liver disease. Fluorescence detecting of MAO-A in living animals is of extremely importance for the early diagnosis of related diseases. However, the development of specific and mitochondrial-targeted MAO-A near-infrared (NIR) fluorescence probes is still lacking. Here, we designed and synthesized four NIR fluorescence probes containing dihydroxanthene (DH) skeleton to detect MAO-A in complex biological systems. The specificity of our representative probe of DHMP2 displays a 31-fold fluorescence turn-on in vitro, and can effectively accumulate in mitochondria and specific detect the endogenous MAO-A concentrations in PC-3 and SH-SY5Y cell lines. Furthermore, the probe DHMP2 can be used for the visualization of the endogenous MAO-A activity in zebrafish and tumor-bearing mice. More importantly, it's the first time to detect the MAO-A activity of hepatic fibrosis tissue through the probe DHMP2. The present studies show that the synthesized DHMP2 might be served as a potential tool for monitoring MAO-A activity in vivo and diagnosing related diseases.