Abstract: Objective  To evaluate the potential of the BIBP-H fluorescent probe in the detection of  the oxidative stress levels after cerebral ischemia-reperfusion (CIRI). Methods  In vitro, the potential of  BIBP-H probe was in detection of oxidative stress was first assessed with fluorescence imaging in rat neuroblastoma (B104) cells after L-glutamic acid stimulation. And then, the effects of edaravone and dexborneol (EDA) and glutathione (GSH) pretreatment on the fluorescence intensity were evaluated. Later, a totally of 28 male C57BL/ 6 mice were randomly assigned into four groups: transient middle cerebral artery occlusion (tMCAO) group, EDA+tMCAO group, GSH+tMCAO group, and sham group. After 1.5 h ischemia and 12 h  reperfusion, the mice were treated with BIBP-H via tail vein injection. In vivo, ex vivo, and tissue fluorescence imaging were utilized to evaluate the probe's cerebral ischemia - reperfusion injury (CIRI).Results  ① BIBP-H probe did not exhibit fluorescence signals in cultured B104 cells, but showed red fluorescence in B104 cells treated with L-glutamic acid. The signals significantly decreased when pretreated with EDA or GSH. ② Both the sham-operated mice intravenously injected with the BIBP-H probe and the tMCAO mice without injection of the probe showed negative results in in vivo fluorescence imaging.  ③ tMCAO mice treated with BIBP-H exhibited red fluorescence signals in the ischemic hemisphere in vivo, with significantly reduced fluorescence intensity after EDA or GSH infusion during reperfusion  ④ The fluorescence area examined with BIBP-H was consistent the cerebral infarction area detected with triphenyltertrazolium. Conclusion  The BIBP-H probe effectively monitored oxidative stress levels both in vivo and in vitro, demonstrating its potential in CIRI detection.

Key words: fluorescent probe, cerebral ischemia/reperfusion, oxidative stress, biological imaging