A Near-Infrared Fluorescent Probe for Monitoring Carboxylesterase Dynamics: Application to NAFLD Diagnosis and Therapeutic Assessment of Qiwei Gandanqing Granules.

As a prevalent metabolic dysfunction, non-alcoholic fatty liver disease (NAFLD) represents an escalating challenge to global healthcare systems. Hepatic carboxylesterases (CES), primarily represented by the CES1 and CES2 isoforms, are important regulators of lipid homeostasis. Emerging evidence suggests that dysregulation of CES1 and CES2 contributes to hepatic lipid accumulation in NAFLD and shows promise as potential biomarkers for NAFLD diagnosis and therapeutic evaluation. Qiwei Gandanqing (QWGDQ), an ethnopharmaceutical preparation rooted in Tibetan and Chinese traditions, has demonstrated significant hepatoprotective properties. However, the precise pathways through which it orchestrates CES activity and re-equilibrates the inflammation-metabolism axis have yet to be fully elucidated. In this study, we engineered OX-CE, a liver-specific near-infrared activatable probe, to track endogenous CES fluctuations in situ. In a high-fat diet-triggered murine model, QWGDQ was found to substantially suppress hepatic steatosis and inflammatory responses. Notably, OX-CE-based imaging revealed a dose-responsive recovery of CES activity, offering a visual confirmation of the formula's therapeutic impact. Mechanistically, QWGDQ alleviates NAFLD by disrupting the antagonistic crosstalk between NF-κB-driven inflammation and PXR-mediated metabolism, thereby restoring enzymatic homeostasis. Our findings emphasize the multi-target therapeutic potential of the formula and concurrently establish the probe as a powerful molecular tool for NAFLD assessment and drug evaluation.