OL-FS13 alleviates experimental cerebral ischemia-reperfusion injury

Cerebral ischemia-reperfusion (I/R) is the main cause of neurological injury after stroke. However, existing treatments for I/R injury are relatively poor, and relevant drugs need to be further explored. Amphibians have received increasing attention as a resource bank of bioactive peptides. However, reports on neuroprotective peptides from amphibians remain extremely rare. Here, we identified a new neuroprotective peptide (OL-FS13, amino acid sequence: FSLLLTWWRRRVC) from the odorous frog species Odorrana livida using a constructed cDNA library. OL-FS13 significantly improving infarct volume, behavioral and histological abnormalities in rats, and also showed neuroprotective activities in PC12 cell (by oxygen glucose deprivation/reoxygenation, OGD/R). Mechanistically, OL-FS13 increased the level of antioxidative enzymes to resist oxidative stress and alleviated endoplasmic reticulum (ER) stress induced by I/R and OGD/R. The use of ML385 (Nrf2 inhibitor) indicated that OL-FS13 relieved nerve damage caused by oxidative and ER stress by increasing the nuclear displacement of Nrf2. Collectively, this research provides a novel drug candidate for the clinical cerebral I/R curation.