Development of peroxynitrite-responsive fluorescence probe for recognition of drug-induced liver injury

A turn-on fluorescence probe for imaging tyrosinase at the wound site in broken tail of zebrafish

Tyrosinase (TYR) is a copper-containing oxidase that affects the synthesis of melanin in the human body, which is regulate to the pigmentation of the skin. Nevertheless, abnormal expression of TYR can lead to albinism, vitiligo and other skin diseases. Excessive accumulation of TYR is a marker of melanoma cancer and an important factor leading to pigmentation during wound healing, freckles and browning of fruits and vegetables. Efficient tracking of TYR is of significance for studying its pathophysiological mechanism. Herein, we synthesized a benzindole-based fluorescent probe Pro-OH to detect TYR in living cells and zebrafish. The probe displayed a high selectivity and sensitivity in distinguishing TYR from other analytes with the low detection limit of 1.024 U/mL. Importantly, Pro-OH was successfully used to imagine TYR at the wound site of broken tail of zebrafish.

Activatable fluorescent probes for early diagnosis and evaluation of liver injury

With the increase in people's living standards, the number of patients suffering from liver injury keeps on increasing. Traditional diagnostic methods can no longer meet the needs of early and accurate diagnosis due to their limitations in application. However, fluorescent probes based on different fluorophores and nanomaterials have been gradually lighting up medical research due to their unique properties, such as high specificity and non-invasiveness. In addition, accurate identification of the different types of liver injury biomarkers can significantly improve the level of early diagnosis. Therefore, this review reviews the fluorescent probes used in the detection of biomarkers of liver injury over recent years and briefly summarizes the corresponding biomarkers of different types of liver injury. Impressively, this review also lists the structures and the response mechanisms of the different probes, and concludes with an outlook, suggesting directions in which improvements can be made. Finally, we hope that this review will contribute to the further development of fluorescent probes for the early diagnosis and assessment of liver injury.

Near-infrared molecular sensor for visualizing and tracking ONOO- during the process of anti-tuberculosis drug-induced liver damage

Isoniazid (INH) and pyrazinamide (PZA) are both the first-line anti-tuberculosis drugs in clinical treatment. It is notable that there are serious side effects of the drugs along with upregulation of reactive nitrogen species, mainly including peripheral neuritis, gastrointestinal reactions, and acute drug-induced liver injury (DILI). Among them, DILI is the most common clinical symptom as well as the basic reason of treatment interruption, protocol change, and drug resistance. As vital reactive nitrogen species (RNS), peroxynitrite (ONOO-) has been demonstrated as a biomarker for evaluation and pre-diagnosis of drug-induced liver injury (DILI). In this work, we developed a red-emitting D-π-A type fluorescence probe DIC-NP which was based on 4'-hydroxy-4-biphenylcarbonitrile modified with dicyanoisophorone as a fluorescent reporter and diphenyl phosphinic chloride group as the reaction site for highly selective and sensitive sensing ONOO-. Probe DIC-NP displayed a low detection limit (14.9 nM) and 60-fold fluorescent enhancement at 669 nm in the sensing of ONOO-. Probe DIC-NP was successfully applied to monitor exogenous and endogenous ONOO- in living HeLa cells and zebrafish. Furthermore, we verified the toxicity of isoniazid (INH) and pyrazinamide (PZA) by taking the oxidative stress induced by APAP as a reference, and successfully imaged anti-tuberculosis drug-induced endogenous ONOO- in HepG2 cells. More importantly, we developed a series of mice models of liver injury and investigated the hepatotoxicity caused by the treatment of anti-tuberculosis drugs. At the same time, H&E of mice organs (heart, liver, spleen, lung, kidney) further confirmed the competence of probe DIC-NP for estimating the degree of drug-induced liver injury, which laid a solid foundation for medical research.

Recent Progress of Spectroscopic Probes for Peroxynitrite and Their Potential Medical Diagnostic Applications

Peroxynitrite (ONOO-) is a crucial reactive oxygen species that plays a vital role in cellular signal transduction and homeostatic regulation. Determining and visualizing peroxynitrite accurately in biological systems is important for understanding its roles in physiological and pathological activity. Among the various detection methods, fluorescent probe-based spectroscopic detection offers real-time and minimally invasive detection, high sensitivity and selectivity, and easy structural and property modification. This review categorizes fluorescent probes by their fluorophore structures, highlighting their chemical structures, recognition mechanisms, and response behaviors in detail. We hope that this review could help trigger novel ideas for potential medical diagnostic applications of peroxynitrite-related molecular diseases.