title: Biochemical characterization of a Caspase-3 far-red fluorescent probe for non-invasive optical imaging of neuronal apoptosis.
abstract: 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 H2O2 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.
authors.affiliation: Rouen Institute for Research and Innovation in Biomedicine (IRIB), University of Rouen, 76821, Mont-Saint-Aignan, France.
authors.forename: Valérie
authors.initials: V
authors.lastname: Jolivel
authors.forename: Sébastien
authors.initials: S
authors.lastname: Arthaud
authors.forename: Béatrice
authors.initials: B
authors.lastname: Botia
authors.forename: Christophe
authors.initials: C
authors.lastname: Portal
authors.forename: Bruno
authors.initials: B
authors.lastname: Delest
authors.forename: Guillaume
authors.initials: G
authors.lastname: Clavé
authors.forename: Jérôme
authors.initials: J
authors.lastname: Leprince
authors.forename: Anthony
authors.initials: A
authors.lastname: Romieu
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Renard
authors.forename: Omar
authors.initials: O
authors.lastname: Touzani
authors.forename: Heidi
authors.initials: H
authors.lastname: Ligeret
authors.forename: Pauline
authors.initials: P
authors.lastname: Noack
authors.forename: Marc
authors.initials: M
authors.lastname: Massonneau
authors.forename: Alain
authors.initials: A
authors.lastname: Fournier
authors.forename: Hubert
authors.initials: H
authors.lastname: Vaudry
authors.forename: David
authors.initials: D
authors.lastname: Vaudry
mesh_terms: D000818:Animals; D017209:Apoptosis; D001921:Brain / Q000166:cytology / Q000378:metabolism; D002232:Carbocyanines / Q000737:chemistry* / Q000493:pharmacokinetics; D053148:Caspase 3 / Q000378:metabolism*; D002478:Cells, Cultured; D005456:Fluorescent Dyes / Q000737:chemistry / Q000493:pharmacokinetics*; D051379:Mice; D008810:Mice, Inbred C57BL; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D009842:Oligopeptides / Q000737:chemistry* / Q000493:pharmacokinetics; D061848:Optical Imaging / Q000379:methods*; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012235:Rhodamines / Q000737:chemistry* / Q000493:pharmacokinetics
chemical_list: D002232:Carbocyanines; D005456:Fluorescent Dyes; D009842:Oligopeptides; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; C000599357:QCASP3.2; D012235:Rhodamines; D053148:Caspase 3