Microrna Mediated Neuroprotective Strategies in Epilepsy Mouse Models
Abstract number :
1.045
Submission category :
1. Basic Mechanisms / 1D. Mechanisms of Therapeutic Interventions
Year :
2022
Submission ID :
2204442
Source :
www.aesnet.org
Presentation date :
12/3/2022 12:00:00 PM
Published date :
Nov 22, 2022, 05:25 AM
Authors :
Durgesh Tiwari, PhD – Cincinnati Childrens Hosp Medical Center; Steve Danzer, PhD – Professor, Anesthesia, Cincinnati Childrens Hosp Medical Center; Christina Gross, PhD – Associate Professor, Neurology, Cincinnati Childrens Hosp Medical Center; Meghna Kilaparthi, UG Research student – Cincinnati Childrens Hosp Medical Center; Rishav Mukherjee, UG Research student – Cincinnati Childrens Hosp Medical Center; Valerine Rajathi, RA -III – Cincinnati Childrens Hosp Medical Center; Andrew Snider, UG Research student – University of Cincinnati, Cincinnati, Ohio 45229, USA
Rationale: Epilepsy embodies an imbalance of network excitability, characterized by EEG abnormalities and seizures. Current treatments are mostly symptomatic targeting single molecules. Novel approaches involving multiple targets could provide better neuroprotection. MicroRNAs (miRNAs) regulate post-transcriptional expression of genes and often regulate several components of a biological pathway. Previous lab studies have shown that inhibiting miR-324-5p reduces seizure severity in acute and chronic mouse models of epilepsy. Here, we examine the antisense mediated (antagomir) inhibition of miR-324-5p and miR-218-5p for its neuroprotective potential in a genetic mouse model. In addition, a novel AAV-microRNA-sponge strategy was investigated for brain region- and cell type-specific (neuronal and glial) effects of miR-324-5p inhibition on seizure susceptibility.
Methods: Cntnap2 KO and littermate control mice were implanted with cortical EEG electrodes at adult (4-5 months) and older (12-16 months) age points. Post EEG confirmation of seizures and spikes, mice were ICV injected with miR-324-5p, miR-218-5p antagomir and scrambled (SCR) control. EEGs were investigated for seizure susceptibility using kainic acid (KA) in younger mice and seizure number in older mice. For the AAV-miR-sponge strategy, C57BL/6 mice were injected with a neuronal (AAV9-Syn-mCherry-miR-324-5p) and glia-specific (AAV5-GFAP-mCherry-miR-324-5p) sponge and SCR control via a bilateral-intrahippocampal injection into the dorsal and ventral hippocampus (4 sites) to achieve stable inhibition. Four weeks post-treatment, these mice were tested for seizure susceptibility using KA and brain tissue was analyzed for specific expression of the sponge.
Results: Cntnap2 mice showed an increased seizure onset in miR-218 antagomir injected mice compared to 324-5p or SCR (p< 0.05) at adult age point. No difference in spike count was observed. Hippocampal and cell type-specific sponge expression was confirmed via mCherry expression. Significantly reduced seizure frequency (p< 0.05) was observed in AAV5-GFAP-mCherry-miR-324-5p-sponge treated mice post KA injection.
Basic Mechanisms