🧬 BDNF Extraction Viewer

Post-stroke seizures are a common and debilitating complication with limited therapeutic options, underscoring the need to identify novel molecular targets. Disruption of chloride homeostasis via impaired potassium chloride cotransporter 2 (KCC2) activity is a key driver of neuronal hyperexcitability. While microglia are a predominant source of brain-derived neurotrophic factor (BDNF) in the acute phase after brain injury, the role of microglial BDNF and its signaling in KCC2 dysregulation and early post-stroke seizure susceptibility remain poorly defined. Using a middle cerebral artery occlusion-reperfusion (MCAO-R) mouse model and oxygen-glucose deprivation/reoxygenation (OGD/R) in hippocampal neurons, we assessed KCC2 function, neuronal excitability, and seizure susceptibility. Pharmacological tools, including the microglial inhibitor minocycline, the TrkB antagonist K252a, the loop diuretic furosemide (FUR), repurposed here as a KCC2-stabilizing agent, and the KCC2 activator CLP290, were employed. Techniques included immunofluorescence, Western blotting, patch-clamp electrophysiology, electroencephalography (EEG), and behavioral seizure assessment. MCAO-R and OGD/R significantly reduced membrane KCC2 expression, leading to a depolarizing shift in the GABA equilibrium potentials (E Our findings identify microglia-derived BDNF/TrkB signaling as a critical upstream pathway mediating KCC2 dysfunction in early post-stroke seizure. Targeting this axis by inhibiting microglial activation, blocking TrkB, or directly enhancing KCC2 function with activators like CLP290 represents a promising therapeutic strategy for stroke-related epilepsy.