Key Questions Answered
Q: Why do people with PTSD have trouble forgetting traumatic memories?
A: Recent research shows that excessive GABA produced by astrocytes via the MAOB enzyme interferes with the brain’s normal fear-extinction processes, preventing the unwanted persistence of traumatic memories.
Q: What is KDS2010 and how might it help treat PTSD?
A: KDS2010 is a brain-penetrant, reversible MAOB inhibitor that lowers astrocyte-derived GABA, restores medial prefrontal cortex function, and reversed PTSD-like behaviors in animal models; it has completed Phase 1 trials and is in further clinical testing.
Q: How did researchers connect clinical symptoms to cellular chemistry?
A: The team used a reverse-translational strategy: they began with neuroimaging in human PTSD patients, identified mPFC abnormalities, and traced those findings to astrocytic MAOB-driven GABA production using postmortem tissue and mouse models.
Summary: A multi-center study led by the Institute for Basic Science and Ewha Womans University identifies astrocyte-derived gamma-aminobutyric acid (GABA) as a central contributor to PTSD. Excessive GABA, produced by monoamine oxidase B (MAOB) in astrocytes, disrupts neural activity in the medial prefrontal cortex (mPFC) and impairs fear extinction. Pharmacological inhibition of MAOB with KDS2010 restored normal brain function and extinguished PTSD-like behaviors in mice, suggesting a new glia-targeted therapeutic avenue for PTSD.
This discovery reframes how we think about PTSD neurobiology: rather than focusing solely on neurons and classic neurotransmitter pathways, it implicates glial cells—specifically astrocytes—in sustaining traumatic memories. Targeting astrocytic GABA production offers a mechanism-driven strategy to improve outcomes for people whose symptoms do not respond to conventional treatments.
Researchers led by Dr. C. Justin Lee and Professor In Kyoon Lyoo combined large-scale human imaging, postmortem tissue analysis, and PTSD-like animal models to pinpoint the cellular source of impaired fear extinction. Brain scans of more than 380 participants revealed that elevated prefrontal GABA levels correlated with reduced cerebral blood flow (CBF) in the mPFC and with the severity of PTSD symptoms. Notably, GABA levels decreased alongside clinical recovery, supporting a causal link between GABA dysregulation and symptom improvement.
To determine where the excess GABA originated, the team examined postmortem human brains and used genetic and pharmacological tools in mouse models. Their results implicate astrocytes—star-shaped glial cells—as the principal source of the abnormal tonic GABA, produced by monoamine oxidase B (MAOB). This astrocyte-derived GABA suppressed neuronal activity and impaired the mPFC’s ability to extinguish fear memories, a hallmark deficit in PTSD.
Crucially, inhibiting MAOB with KDS2010, a highly selective and reversible compound developed at the Institute for Basic Science, normalized astrocytic GABA, restored mPFC blood flow, reduced astrogliosis, and rescued fear extinction in PTSD-like mice. Because KDS2010 has already passed Phase 1 safety testing in humans and advanced to Phase 2 evaluation, it represents a promising candidate for mechanism-based PTSD treatment.
The study is a clear example of reverse translational research: clinical observations guided cellular and molecular experiments, which in turn validated a druggable target. This translational loop strengthens confidence that targeting MAOB and astrocytic GABA could translate into clinically meaningful benefits for patients.
Key Facts
- Astrocyte Role: Astrocyte-produced GABA, not neuronal GABA, is linked to impaired fear extinction in PTSD.
- Drug Discovery: KDS2010, a reversible MAOB inhibitor, reduced tonic GABA, restored mPFC function, and normalized fear responses in mice.
- Reverse Translation: Human neuroimaging findings guided laboratory studies, connecting clinical symptoms to astrocytic dysfunction and a tractable therapeutic target.
Source: Institute for Basic Science
Background
Post-traumatic stress disorder (PTSD) is a chronic psychiatric condition in which fear memories persist long after the original threat has ended. Current pharmacotherapies, primarily targeting serotonin systems, help only a subset of patients and do not directly address the mechanisms that prevent fear extinction. By contrast, the new findings identify MAOB-dependent astrocytic GABA as a mechanistic driver of extinction deficits and demonstrate that MAOB inhibition can reverse those deficits in preclinical models.
The investigators emphasize that astrocytes are active regulators of neural circuits and can shape behavioral outcomes in psychiatric disorders. Their work opens the door to glia-targeted therapies for PTSD and potentially for other disorders characterized by disrupted cortical inhibition, including panic disorder, depression, and schizophrenia.
With KDS2010 advancing through clinical development, the research provides translational momentum toward first-in-class treatments that specifically normalize astrocytic GABA signaling. Future studies will further evaluate efficacy, dosing, and long-term outcomes in people with PTSD.
About this PTSD and neuropharmacology research news
Author: William Suh
Source: Institute for Basic Science
Contact: William Suh – Institute for Basic Science
Image: The image is credited to Neuroscience News
Original Research: Open access. “Astrocytic gamma-aminobutyric acid dysregulation as a therapeutic target for posttraumatic stress disorder” by C. Justin Lee et al., published in Signal Transduction and Targeted Therapy.
Abstract
Astrocytic gamma-aminobutyric acid dysregulation as a therapeutic target for posttraumatic stress disorder
PTSD is a disabling psychiatric disorder with substantial unmet treatment needs. Comprehensive clinical studies identified elevated prefrontal GABA levels that correlate with impaired cerebral blood flow and clinical severity in PTSD, normalizing with recovery. Postmortem analyses and animal models traced this imbalance to MAOB-dependent GABA production in astrocytes, which disrupts fear extinction. Genetic and pharmacological MAOB inhibition restored astrocytic GABA balance and improved extinction retrieval in PTSD-like mice. KDS2010, a selective reversible MAOB inhibitor, rescued prefrontal CBF deficits, reduced tonic GABA and astrogliosis, and completed Phase 1 safety testing, supporting progression to Phase 2 trials. These findings establish astrocytic GABA dysregulation as a core pathophysiological mechanism in PTSD and position MAOB inhibition as a targeted therapeutic strategy, bridging human imaging, cellular studies, animal models, and translational clinical trials.