Biochemical Characterization of a Caspase-3 Far-red Fluorescent Probe for Non-invasive Optical Imaging of Neuronal Apoptosis

• Published in: Journal of molecular neuroscience 2014-11, Vol.54 (3), p.451-462
• Main Authors: Jolivel, Valérie, Arthaud, Sébastien, Botia, Béatrice, Portal, Christophe, Delest, Bruno, Clavé, Guillaume, Leprince, Jérôme, Romieu, Anthony, Renard, Pierre-Yves, Touzani, Omar, Ligeret, Heidi, Noack, Pauline, Massonneau, Marc, Fournier, Alain, Vaudry, Hubert, Vaudry, David
• Format: Article
• Language: English
• Subjects: Animals; Apoptosis; Biomedical and Life Sciences; Biomedicine; Brain; Brain - cytology; Brain - metabolism; Carbocyanines; Carbocyanines - chemistry; Carbocyanines - pharmacokinetics; Caspase 3; Caspase 3 - metabolism; Cell Biology; Cell death; Cells, Cultured; Chemical Sciences; Enzymes; Fluorescent Dyes; Fluorescent Dyes - chemistry; Fluorescent Dyes - pharmacokinetics; Human health and pathology; Infectious diseases; Ischemia; Life Sciences; Mice; Mice, Inbred C57BL; Morphology; Neurochemistry; Neurology; Neurons; Neurons - drug effects; Neurons - metabolism; Neurons and Cognition; Neurosciences; Oligopeptides; Oligopeptides - chemistry; Oligopeptides - pharmacokinetics; Optical Imaging; Optical Imaging - methods; Pharmaceutical sciences; Pharmacology; Pituitary Adenylate Cyclase-Activating Polypeptide; Pituitary Adenylate Cyclase-Activating Polypeptide - pharmacology; Proteomics; Rats; Rats, Wistar; Rhodamines; Rhodamines - chemistry; Rhodamines - pharmacokinetics; Toxicology
• ISSN: 0895-8696; 1559-1166
• DOI: 10.1007/s12031-014-0325-4

Apoptosis is a regulated process, leading to cell death, which is involved in several pathologies including neurodegenerative diseases and stroke. Caspase-3 is a key enzyme of the apoptotic pathway and is considered as a major target for the treatment of abnormal cell death. Sensitive and non-invasive methods to monitor caspase-3 activity in cells and in the brain of living animals are needed to test the efficiency of novel therapeutic strategies. In the present study, we have biochemically characterized a caspase-3 far-red fluorescent probe, QCASP3.2, that can be used to detect apoptosis in vivo. The specificity of cleavage of QCASP3.2 was demonstrated using recombinant caspases and protease inhibitors. The functionality of the probe was also established in cerebellar neurons cultured in apoptotic conditions. QCASP3.2 did not exhibit any toxicity and appeared to accurately reflect the induction and inhibition of caspase activity by H 2 O 2 and PACAP, respectively, both in cell lysates and in cultured neurons. Finally, intravenous injection of the probe after cerebral ischemia revealed activation of caspase-3 in the infarcted hemisphere. Thus, the present study demonstrates that QCASP3.2 is a suitable probe to monitor apoptosis both in vitro and in vivo and illustrates some of the possible applications of this caspase-3 fluorescent probe.