Abstract T P87: Hydrogen Sulfide Enhances Neurogenesis through the IRAK-1/GSK3β/AKT Signaling Pathways after Ischemic Stroke
Background and purpose: Increasing evidence signifying that inflammation has an ample role in the ischemia and; neurogenesis is somehow affected by inflammation. Current approved therapy for stroke is limited and new strategies need to be investigated. Hydrogen sulfide (H2S) showed neuro-protective however, role of H2S in stroke-induced neurogenesis is not known. Therefore, the present study was to determine the role of H2S in ischemia induced neurogenesis. Methods: To perform this study; we employed 8-10 weak old C57BL/6 mice with following groups: WT-Sham; WT+ ischemia reperfusion (IR) for 7 days; IR+GYY4137 (H2S donor, 30μM for 7 days; Intra peritoneal injection); and Sham+ GYY4137 (30μM for 7 day). Ischemia was created by the middle cerebral artery occlusion, (MCAO) for 50 min followed by reperfusion for 7 days. The brain tissue from different groups was used for biochemical, infarct area molecular and immunohistochemistry analysis. Data were analyzed by one way ANOVA followed by Tukey test. Results: We found increased protein expression of IRAK-1 (F=3, 27.01; P<.005), GSK3β 9 (F=3, 89.47; P<.005), p-AKT (F=3, 89.47; P<.005) and reduced expression of AKT p-AKT(F=3, 112.2; P<.005) in I/R group as compared to sham that indicates alteration of inflammatory signaling pathways. Further, we also found decreased level of Nestin (F=3, 35.32; P<.005), GFAP (F=3, 95.14; P<.001), NeuN (F=3, 123.4; P<.001), TUJ-1 (F=3, 112; P<.005), MAP-2 (F=3, 31.54; P<.0001), IL-6 (F=3, 55.7; p<.05) and BDNF (F=3, 166.5; P<.005) in cortical region of I/R group which indicates loss of neuronal function. Additionally, immunohistochemistry assay also revealed the loss of Nestin (P<.05), BDNF (P<.05), MAP-2 (P<.05) along with increased GSK-3β (P<.005) expression in sub ventricular zone (SVZ) and hippocampal region. Further, GYY4137 treatment for 7 days in ischemic group significantly restored the Nestin, GFAP, IL-6, NeuN, TUJ-1, MAP-2 and BDNF levels via regulating IRAK-1/GSK3β/AKT signaling pathways. Conclusion: Present study clearly demonstrate that H2S plays an important role in ischemia induced neurogenesis as well as protecting neuronal function through inhibition of IRAK1/GSK3β/AKT signaling pathways.
Acknowledgement: This work was supported by NTHL107640-NT.
Author Disclosures: P.K. Kamat: None. A. Kalani: None. N. Tyagi: None.
- © 2015 by American Heart Association, Inc.