Near-Infrared Fluorescent Probe Reveals Elevated Mitochondrial Viscosity during Acute Alcoholic Liver Injury

Abstract

Acute alcoholic liver injury (AALI) has become an important cause of liver disease worldwide, and there is an urgent need to develop noninvasive and sensitive methods to detect and evaluate AALI. We report herein three novel but readily available mitochondrial targeting fluorescence probes (<b>ICR</b>, <b>ICJ</b>, and <b>ICQ</b>) for AALI detection. These probes contain different electron-donating groups, among which <b>ICQ</b> exhibits NIR fluorescence (740 nm), a large Stokes shift (110 nm), and a sensitive response to viscosity (73-fold enhancement in fluorescence from water to glycerol), making it suitable for <i>in vivo</i> imaging. <b>ICQ</b> also exhibits an excellent ability to image mitochondrial viscosity changes in cells. More importantly, <b>ICQ</b> can target the liver selectively and image the viscosity changes in the liver noninvasively. Through establishing an AALI mouse model, <b>ICQ</b> was successfully applied to the <i>in situ</i> imaging changes in liver viscosity during the AALI process. The results showed a significant increase in liver viscosity in AALI mice, indicating that viscosity can serve as a marker for AALI, and <b>ICQ</b> is a promising noninvasive and sensitive tool for detecting and evaluating AALI.