AMPA GluA1-flip targeted oligonucleotide therapy reduces neonatal seizures and hyperexcitability.
Glutamate-activated α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPA-Rs) mediate the majority of excitatory neurotransmission in brain and thus are major drug targets for diseases associated with hyperexcitability or neurotoxicity. Due to the critical nature of AMPA-Rs in normal brain function, typical AMPA-R antagonists have deleterious effects on cognition and motor function, highlighting the need for more precise modulators. A dramatic increase in the flip isoform of alternatively spliced AMPA-R GluA1 subunits occurs post-seizure in humans and animal models. GluA1-flip produces higher gain AMPA channels than GluA1-flop, increasing network excitability and seizure susceptibility. Splice modulating oligonucleotides (SMOs) bind to pre-mRNA to influence alternative splicing, a strategy that can be exploited to develop more selective drugs across therapeutic areas. We developed a novel SMO, GR1, which potently and specifically decreased GluA1-flip expression throughout the brain of neonatal mice lasting at least 60 days after single intracerebroventricular injection. GR1 treatment reduced AMPA-R mediated excitatory postsynaptic currents at hippocampal CA1 synapses, without affecting long-term potentiation or long-term depression, cellular models of memory, or impairing GluA1-dependent cognition or motor function in mice. Importantly, GR1 demonstrated anti-seizure properties and reduced post-seizure hyperexcitability in neonatal mice, highlighting its drug candidate potential for treating epilepsies and other neurological diseases involving network hyperexcitability.
Graduate Program in Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America.|LifeSplice Pharma, Malvern, Pennsylvania, United States of America.
Nicole M
NM
Lykens
Department of Biology, Widener University, Chester, Pennsylvania, United States of America.
David J
http://orcid.org/0000-0002-2597-4261
DJ
Coughlin
Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America.
Jyoti M
JM
Reddi
LifeSplice Pharma, Malvern, Pennsylvania, United States of America.|Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America.
Gordon J
GJ
Lutz
LifeSplice Pharma, Malvern, Pennsylvania, United States of America.|Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America.
Melanie K
MK
Tallent
D017398:Alternative Splicing; D000818:Animals; D000831:Animals, Newborn; D001483:Base Sequence; D003071:Cognition; D004195:Disease Models, Animal; D004198:Disease Susceptibility; D005260:Female; D006624:Hippocampus / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D051379:Mice; D009043:Motor Activity; D009841:Oligonucleotides / Q000008:administration & dosage* / Q000737:chemistry; D017966:Pyramidal Cells / Q000378:metabolism; D018091:Receptors, AMPA / Q000235:genetics*; D012640:Seizures / Q000235:genetics* / Q000503:physiopathology* / Q000628:therapy; D009435:Synaptic Transmission / Q000235:genetics
D009841:Oligonucleotides; D018091:Receptors, AMPA