Prediction value of pericoronary fat attenuation index for coronary in-stent restenosis.

OBJECTIVES: As a novel imaging marker, pericoronary fat attenuation index (FAI) reflects the local coronary inflammation which is one of the major mechanisms for in-stent restenosis (ISR). We aimed to validate the ability of pericoronary FAI to predict ISR in patients undergoing percutaneous coronary intervention (PCI). MATERIALS AND METHODS: Patients who underwent coronary CT angiography (CCTA) before PCI within 1 week between January 2017 and December 2019 at our hospital and had follow-up invasive coronary angiography (ICA) or CCTA were enrolled. Pericoronary FAI was measured at the site where stents would be placed. ISR was defined as ≥ 50% diameter stenosis at follow-up ICA or CCTA in the in-stent area. Multivariable analysis using mixed effects logistic regression models was performed to test the association between pericoronary FAI and ISR at lesion level. RESULTS: A total of 126 patients with 180 target lesions were included in the study. During 22.5 months of mean interval time from index PCI to follow-up ICA or CCTA, ISR occurred in 40 (22.2%, 40/180) stents. Pericoronary FAI was associated with a higher risk of ISR (adjusted OR = 1.12, p = 0.028). The optimum cutoff was - 69.6 HU. Integrating the dichotomous pericoronary FAI into current state of the art prediction model for ISR improved the prediction ability of the model significantly (△area under the curve = + 0.064; p = 0.001). CONCLUSION: Pericoronary FAI around lesions with subsequent stent placement is independently associated with ISR and could improve the ability of current prediction model for ISR. CLINICAL RELEVANCE STATEMENT: Pericoronary fat attenuation index can be used to identify the lesions with high risk for in-stent restenosis. These lesions may benefit from extra anti-inflammation treatment to avoid in-stent restenosis. KEY POINTS: • Pericoronary fat attenuation index reflects the local coronary inflammation. • Pericoronary fat attenuation index around lesions with subsequent stents placement can predict in-stent restenosis. • Pericoronary fat attenuation index can be used as a marker for future in-stent restenosis.

Residual Risk in Non-ST-Segment Elevation Acute Coronary Syndrome: Quantitative Plaque Analysis at Coronary CT Angiography.

Background Lipid-rich plaques detected with intravascular imaging are associated with adverse cardiovascular events in patients with non-ST-segment elevation (NSTE) acute coronary syndrome (ACS). But evidence about the prognostic implication of coronary CT angiography (CCTA) in NSTE ACS is limited. Purpose To assess whether quantitative variables at CCTA that reflect lipid content in nonrevascularized plaques in individuals with NSTE ACS might be predictors of subsequent nonrevascularized plaque-related major adverse cardiovascular events (MACEs). Materials and Methods In this multicenter prospective cohort study, from November 2017 to January 2019, individuals diagnosed with NSTE ACS (excluding those at very high risk) were enrolled and underwent CCTA before invasive coronary angiography (ICA) within 1 day. Lipid core was defined as areas with attenuation less than 30 HU in plaques. MACEs were defined as cardiac death, myocardial infarction, hospitalization for unstable angina, and revascularization. Participants were followed up at 6 months, 12 months, and annually thereafter for at least 3 years (ending by July 2022). Multivariable analysis using Cox proportional hazards regression models was performed to determine the association between lipid core burden, lipid core volume, and future nonrevascularized plaque-related MACEs at both the participant and plaque levels. Results A total of 342 participants (mean age, 57.9 years ± 11.1 [SD]; 263 male) were included for analysis with a median follow-up period of 4.0 years (IQR, 3.6-4.4 years). The 4-year nonrevascularized plaque-related MACE rate was 23.9% (95% CI: 19.1, 28.5). Lipid core burden (hazard ratio [HR], 12.6; 95% CI: 4.6, 34.3) was an independent predictor at the participant level, with an optimum threshold of 2.8%. Lipid core burden (HR, 12.1; 95% CI: 6.6, 22.3) and volume (HR, 11.0; 95% CI: 6.5, 18.4) were independent predictors at the plaque level, with an optimum threshold of 7.2% and 10.1 mm3, respectively. Conclusion In NSTE ACS, quantitative analysis of plaque lipid content at CCTA independently predicted participants and plaques at higher risk for future nonrevascularized plaque-related MACEs. Chinese Clinical Trial Registry no. ChiCTR1800018661 © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Tavakoli and Duman in this issue.

p38 MAPK Endogenous Inhibition Improves Neurological Deficits in Global Cerebral Ischemia/Reperfusion Mice.

Cerebral ischemia/reperfusion (I/R) injury is a complex pathophysiological process that can lead to neurological function damage and the formation of cerebral infarction. The p38 MAPK pathway has attracted considerable attention in cerebral I/R injury (IRI), but little research has been carried out on its direct role in vivo. In this study, to observe the effects of p38 MAPK endogenous inhibition on cerebral IRI, p38 heterozygous knockdown (p38KI/+) mice were used. We hypothesized that p38 signaling might be involved in I/R injury and neurological damage reduction and that neurological behavioral deficits improve when p38 MAPK is inhibited. First, we examined the neurological damage and neurological behavioral deficit effects of I/R injury in WT mice. Cerebral I/R injury was induced by the bilateral common carotid artery occlusion (BCCAO) method. The cerebral infarction area and volume were assessed and analyzed by 2,3,5-triphenyltetrazolium chloride (TTC) staining. p38 MAPK and caspase-3 were detected by western blotting. Neuronal apoptosis was measured using TUNEL staining. Neurological deficits were detected by behavioral testing. Furthermore, to assess whether these neuroprotective effects occurred when p38 MAPK was inhibited, p38 heterozygous knockdown (p38KI/+) mice were used. We found that p38 MAPK endogenous inhibition rescued hippocampal cell apoptosis, reduced ischemic penumbra, and improved neurological behavioral deficits. These findings showed that p38 MAPK endogenous inhibition had a neuroprotective effect on IRI and that p38 MAPK may be a potential therapeutic target for cerebral IRI.

Absence of TRIM32 Leads to Reduced GABAergic Interneuron Generation and Autism-like Behaviors in Mice via Suppressing mTOR Signaling.

Mammalian target of rapamycin (mTOR) signaling plays essential roles in brain development. Hyperactive mTOR is an essential pathological mechanism in autism spectrum disorder (ASD). Here, we show that tripartite motif protein 32 (TRIM32), as a maintainer of mTOR activity through promoting the proteasomal degradation of G protein signaling protein 10 (RGS10), regulates the proliferation of medial/lateral ganglionic eminence (M/LGE) progenitors. Deficiency of TRIM32 results in an impaired generation of GABAergic interneurons and autism-like behaviors in mice, concomitant with an elevated autophagy, which can be rescued by treatment embryonically with 3BDO, an mTOR activator. Transplantation of M/LGE progenitors or treatment postnatally with clonazepam, an agonist of the GABAA receptor, rescues the hyperexcitability and the autistic behaviors of TRIM32-/- mice, indicating a causal contribution of GABAergic disinhibition. Thus, the present study suggests a novel mechanism for ASD etiology in that TRIM32 deficiency-caused hypoactive mTOR, which is linked to an elevated autophagy, leads to autism-like behaviors via impairing generation of GABAergic interneurons. TRIM32-/- mouse is a novel autism model mouse.

Amyloid precursor protein enhances Nav1.6 sodium channel cell surface expression.

Amyloid precursor protein (APP) is commonly associated with Alzheimer disease, but its physiological function remains unknown. Nav1.6 is a key determinant of neuronal excitability in vivo. Because mouse models of gain of function and loss of function of APP and Nav1.6 share some similar phenotypes, we hypothesized that APP might be a candidate molecule for sodium channel modulation. Here we report that APP colocalized and interacted with Nav1.6 in mouse cortical neurons. Knocking down APP decreased Nav1.6 sodium channel currents and cell surface expression. APP-induced increases in Nav1.6 cell surface expression were Go protein-dependent, enhanced by a constitutively active Go protein mutant, and blocked by a dominant negative Go protein mutant. APP also regulated JNK activity in a Go protein-dependent manner. JNK inhibition attenuated increases in cell surface expression of Nav1.6 sodium channels induced by overexpression of APP. JNK, in turn, phosphorylated APP. Nav1.6 sodium channel surface expression was increased by T668E and decreased by T668A, mutations of APP695 mimicking and preventing Thr-668 phosphorylation, respectively. Phosphorylation of APP695 at Thr-668 enhanced its interaction with Nav1.6. Therefore, we show that APP enhances Nav1.6 sodium channel cell surface expression through a Go-coupled JNK pathway.

AMP-activated protein kinase α2 protects against liver injury from metastasized tumors via reduced glucose deprivation-induced oxidative stress.

It is well known that tumors damage affected tissues; however, the specific mechanism underlying such damage remains elusive. AMP-activated protein kinase (AMPK) senses energetic changes and regulates glucose metabolism. In this study, we examined the mechanisms by which AMPK promotes metabolic adaptation in the tumor-bearing liver using a murine model of colon cancer liver metastasis. Knock-out of AMPK α2 significantly enhanced tumor-induced glucose deprivation in the liver and increased the extent of liver injury and hepatocyte death. Mechanistically, we observed that AMPK α2 deficiency resulted in elevated reactive oxygen species, reduced mitophagy, and increased cell death in response to tumors or glucose deprivation in vitro. These results imply that AMPK α2 is essential for attenuation of liver injury during tumor metastasis via hepatic glucose deprivation and mitophagy-mediated inhibition of reactive oxygen species production. Therefore, AMPK α2 might represent an important therapeutic target for colon cancer metastasis-induced liver injury.

G protein coupled receptor 50 promotes self-renewal and neuronal differentiation of embryonic neural progenitor cells through regulation of notch and wnt/ß-catenin signalings.

G protein-coupled receptor 50 (GPR50), a risk factor for major depressive disorder and bipolar affective disorder, is expressed in both the developmental and adult brain. However, the function of GPR50 in the brain remains unknown. We here show GPR50 is expressed by neural progenitor cells (NPCs) in the ventricular zone of embryonic brain. Knockdown of GPR50 with a small interference RNA (siRNA) decreased self-renewal and neuronal differentiation, but not glial differentiation of NPCs. Moreover, overexpression of either full-length GPR50 or the intracellular domain of GPR50, rather than the truncated GPR50 in which the intracellular domain is deleted in, increased neuronal differentiation, indicating that GPR50 promotes neuronal differentiation of NPCs in an intracellular domain-dependent manner. We further described that the transcriptional activity of the intracellular domain of notch on Hes1 gene was repressed by overexpression of GPR50. In addition, decreased levels of transcription factor 7-like 2 (TCF7L2) mRNA was observed in GPR50 siRNA-transfected NPCs, suggesting that knockdown of GPR50 impairs wnt/ß-catenin signaling. Moreover, the mRNA levels of neurogenin (Ngn) 1, Ngn2 and cyclin D1, the target genes of notch and wnt/ß-catenin signalings, in NPCs were reduced by knockdown of GPR50. Therefore, GPR50 promotes self-renewal and neuronal differentiation of NPCs possibly through regulation of notch and wnt/ß-catenin signalings.

Making synapses strong: metaplasticity prolongs associativity of long-term memory by switching synaptic tag mechanisms.

One conceptual mechanism for the induction of associative long-term memory is that a synaptic tag, set by a weak event, can capture plasticity-related proteins from a nearby strong input, thus enabling associativity between the 2 (synaptic tagging and capture, STC). So far, STC has been observed for only a limited time of 60 min. Nevertheless, association of weak memory forms can occur beyond this period and its mechanism is not well understood. Here we report that metaplasticity induced by ryanodine receptor activation or synaptic activation of metabotropic glutamate receptors prolongs the durability of the synaptic tag, thus extending the time window for associative interactions mediating storage of long-term memory. We provide evidence that such metaplasticity alters the mechanisms of STC from a CaMKII-mediated (in non-primed STC) to a protein kinase Mzeta (PKMζ)-mediated process (in primed STC). Thus the association of weak synapses with strong synapses in the "late" stage of associative memory formation occurs only through metaplasticity. The results also reveal that the short-lived, CaMKII-mediated tag may contribute to a mechanism for a fragile form of memory while metaplasticity enables a PKMζ-mediated synaptic tag capable of prolonged interactions that induce a more stable form of memory that is resistant to reversal.

Crystal structure of the N-terminal methyltransferase-like domain of anamorsin.

Anamorsin is a recently identified molecule that inhibits apoptosis during hematopoiesis. It contains an N-terminal methyltransferase-like domain and a C-terminal Fe-S cluster motif. Not much is known about the function of the protein. To better understand the function of anamorsin, we have solved the crystal structure of the N-terminal domain at 1.8 Å resolution. Although the overall structure resembles a typical S-adenosylmethionine (SAM) dependent methyltransferase fold, it lacks one α-helix and one ß-strand. As a result, the N-terminal domain as well as the full-length anamorsin did not show S-adenosyl-L-methionine (AdoMet) dependent methyltransferase activity. Structural comparisons with known AdoMet dependent methyltransferases reveals subtle differences in the SAM binding pocket that preclude the N-terminal domain from binding to AdoMet. The N-terminal methyltransferase-like domain of anamorsin probably functions as a structural scaffold to inhibit methyl transfers by out-competing other AdoMet dependant methyltransferases or acts as bait for protein-protein interactions.

Deletion of TRIM32 protects mice from anxiety- and depression-like behaviors under mild stress.

Chronic stress causes a variety of psychiatric disorders such as anxiety and depression, but its mechanism is not well understood. Tripartite motif-containing protein 32 (TRIM32) was strongly associated with autism spectrum disorder, attention deficit hyperactivity disorder, anxiety and obsessive compulsive disorder based on a study of copy number variation, and deletion of TRIM32 increased neural proliferation and reduced apoptosis. Here, we propose that TRIM32 is involved in chronic stress-induced affective behaviors. Using a chronic unpredictable mild stress mouse depression model, we studied expression of TRIM32 in brain tissue samples and observed behavioral changes in Trim32 knockout mice. The results showed that TRIM32 protein but not its mRNA was significantly reduced in hippocampus in a time-dependent manner within 8 weeks of chronic stress. These stress-induced affective behaviors and reduction of TRIM32 protein expression were significantly reversed by antidepressant fluoxetine treatment. In addition, Trim32 knockout mice showed reduced anxiety and depressive behaviors and hyperactivities compared with Trim32 wild-type mice under normal and mild stress conditions. We conclude that TRIM32 plays important roles in regulation of hyperactivities and positively regulates the development of anxiety and depression disorders induced by chronic stress.

Pulmonary arterial hypertension in HIV infection: a concise review.

Pulmonary arterial hypertension (PAH) is an infrequent but nevertheless serious life threatening severe complication of human immunodeficiency virus (HIV) infection. In today's era of antiretroviral therapy (ART), the mortality of HIV patients has greatly reduced due to improved immune function and fewer opportunistic infections. However, these patients have an increased incidence of PAH. In this review, we will mainly discuss HIV-related pulmonary arterial hypertension (HRPH) in terms of the epidemiology, pathogenesis, clinical characteristics and treatment.

Protocol to detect telomerase activity in adult mouse hippocampal neural progenitor cells using the telomeric repeat amplification protocol assay.

Changes in telomerase activity and telomere length contribute to aging-related decline. Investigating telomerase in aging models provides insights into related pathologies. Here, we present a protocol to detect telomerase activity in adult mouse hippocampal neural progenitor cells using the telomeric repeat amplification protocol assay. We describe steps for isolating and expanding aged mouse hippocampal neural progenitor cells (NPCs) and assessing telomerase using a non-radioactive technique. The protocol emphasizes the significance of understanding telomerase activity in NPCs for neurogenesis and age-related diseases.

Cell-specific Nav1.6 knockdown reduced astrocyte-derived Aß by reverse Na+-Ca2+ transporter-mediated autophagy in alzheimer-like mice.

INTRODUCTION: Nav1.6 is closely related to the pathology of Alzheimer's Disease (AD), and astrocytes have recently been identified as a significant source of ß-amyloid (Aß). However, little is known about the connection between Nav1.6 and astrocyte-derived Aß. OBJECTIVE: This study explored the crucial role of Nav1.6 in mediated astrocyte-derived Aß in AD and knockdown astrocytic Nav1.6 alleviates AD progression by promoting autophagy and lysosome-APP fusion. METHODS: A mouse model for astrocytic Nav1.6 knockdown was constructed to study the effects of astrocytic Nav1.6 on amyloidosis. The role of astrocytic Nav1.6 on autophagy and lysosome-APP(amyloid precursor protein) fusion was used by transmission electron microscope, immunostaining, western blot and patch clamp. Glial cell activation was detected using immunostaining. Neuroplasticity and neural network were assessed using patch-clamp, Golgi stain and EEG recording. Behavioral experiments were performed to evaluate cognitive defects. RESULTS: Astrocytic Nav1.6 knockdown reduces amyloidosis, alleviates glial cell activation and morphological complexity, improves neuroplasticity and abnormal neural networks, as well as promotes learning and memory abilities in APP/PS1 mice. Astrocytic Nav1.6 knockdown reduces itself-derived Aß by promoting lysosome- APP fusion, which is related to attenuating reverse Na+-Ca2+ exchange current thus reducing intracellular Ca2+ to facilitate autophagic through AKT/mTOR/ULK pathway. CONCLUSION: Our findings unveil the crucial role of astrocyte-specific Nav1.6 in reducing astrocyte-derived Aß, highlighting its potential as a cell-specific target for modulating AD progression.

The changes of serum angiotensin-converting enzyme 2 in patients with pulmonary arterial hypertension due to congenital heart disease.

BACKGROUND: Angiotensin-converting enzyme 2 (ACE2), a primary component of the vasoprotective axis in the renin-angiotensin system (RAS), has recently been found to have regulatory actions in hypoxic pulmonary hypertension and monocrotaline-induced pulmonary hypertension. We explored the hypothesis that the level of ACE2 protein contents may be decreased in patients with pulmonary arterial hypertension (PAH) due to congenital heart disease (CHD). OBJECTIVE: We observed the serum ACE2 protein contents in patients with PAH due to CHD (CHD-PAH), and investigated their correlation with mean pulmonary arterial pressure (mPAP). METHODS: One hundred and four patients with CHD and 33 normal control patients (group A) were involved in the research. The patients with CHD were divided into 55 cases of nonpulmonary hypertension (group B), 25 cases of mild to moderate pulmonary hypertension (group C) and 24 cases of severe pulmonary hypertension (group D). The serum level of ACE2 protein contents were detected by enzyme-linked immunosorbent assay (ELISA), and the relationship between these contents and mPAP were analyzed. RESULTS: ACE2 protein contents significantly declined as mPAP increased. The mPAP was negatively correlated with the level of ACE2 protein contents. CONCLUSIONS: These results demonstrated that ACE2 may play an important regulatory role in CHD-PAH.

Recent advances in biomimetic nanodelivery systems: New brain-targeting strategies.

In recent years, brain diseases have seriously threatened human health due to their high morbidity and mortality. Achieving efficient drug delivery to provide satisfactory therapeutic outcomes is currently the greatest challenge in treating brain diseases. The main challenges are the structural peculiarities of the brain and the inability to transport drugs across the blood-brain barrier. Biomimetic nanodelivery systems (BNDSs) applied to the brain have been extensively developed in the preclinical phase to surmount these challenges. Considering the inherent properties of BNDSs, the substantially enhanced ability of BNDS to carry therapeutic agents and their higher selectivity toward lesions offer new opportunities for developing safe and effective therapies. This review summarizes brain-targeting nanotherapies, particularly advanced therapies with biomimetic nano-assistance. Prospects for developing BNDSs and the challenges of their clinical translation are discussed. Understanding and implementing biomimetic nanotherapies may facilitate the development of new targeted strategies for brain disorders.

Receptor-like protein-tyrosine phosphatase α enhances cell surface expression of neural adhesion molecule NB-3.

Neural adhesion molecule NB-3 plays an important role in the apical dendrite development of layer V pyramidal neurons in the visual cortex, and receptor-like protein-tyrosine phosphatase α (PTPα) mediates NB-3 signaling in this process. Here we investigated the role of PTPα in regulating cell surface expression of NB-3. We found that cortical neurons from PTPα knock-out mice exhibited a lower level of NB-3 at the cell surface. When expressed in COS1 cells, NB-3 was enriched in the Golgi apparatus with a low level of cell surface expression. However, co-expression of PTPα increased the cell surface distribution of NB-3. Further analysis showed that PTPα facilitated Golgi exit of NB-3 and stabilized NB-3 protein at the cell surface by preventing its release from the plasma membrane. The extracellular region of PTPα but not its catalytic activity is necessary for its effect on NB-3 expression. Thus, the PTPα-mediated increase of NB-3 level at the cell surface represents a novel function of PTPα in NB-3 signaling in neural development.

Neural recognition molecules CHL1 and NB-3 regulate apical dendrite orientation in the neocortex via PTP alpha.

Apical dendrites of pyramidal neurons in the neocortex have a stereotypic orientation that is important for neuronal function. Neural recognition molecule Close Homolog of L1 (CHL1) has been shown to regulate oriented growth of apical dendrites in the mouse caudal cortex. Here we show that CHL1 directly associates with NB-3, a member of the F3/contactin family of neural recognition molecules, and enhances its cell surface expression. Similar to CHL1, NB-3 exhibits high-caudal to low-rostral expression in the deep layer neurons of the neocortex. NB-3-deficient mice show abnormal apical dendrite projections of deep layer pyramidal neurons in the visual cortex. Both CHL1 and NB-3 interact with protein tyrosine phosphatase alpha (PTPalpha) and regulate its activity. Moreover, deep layer pyramidal neurons of PTPalpha-deficient mice develop misoriented, even inverted, apical dendrites. We propose a signaling complex in which PTPalpha mediates CHL1 and NB-3-regulated apical dendrite projection in the developing caudal cortex.

Potential role of 20S proteasome in maintaining stem cell integrity of human bone marrow stromal cells in prolonged culture expansion.

Human bone marrow stromal cells (hBMSCs) could be used in clinics as precursors of multiple cell lineages following proper induction. Such application is impeded by their characteristically short lifespan, together with the increasing loss of proliferation capability and progressive reduction of differentiation potential after the prolonged culture expansion. In the current study, we addressed the possible role of 20S proteasomes in this process. Consistent with prior reports, long-term in vitro expansion of hBMSCs decreased cell proliferation and increased replicative senescence, accompanied by reduced activity and expression of the catalytic subunits PSMB5 and PSMB1, and the 20S proteasome overall. Application of the proteasome inhibitor MG132 produced a senescence-like phenotype in early passages, whereas treating late-passage cells with 18α-glycyrrhetinic acid (18α-GA), an agonist of 20S proteasomes, delayed the senescence progress, enhancing the proliferation and recovering the capability of differentiation. The data demonstrate that activation of 20S proteasomes assists in counteracting replicative senescence of hBMSCs expanded in vitro.

CHL1 negatively regulates the proliferation and neuronal differentiation of neural progenitor cells through activation of the ERK1/2 MAPK pathway.

Neural recognition molecules of the immunoglobulin superfamily play important roles in the development and regeneration of nervous system. Close Homologue of L1 (CHL1) is a member of the L1 family of recognition molecules which are expressed during neuronal development, suggesting a potential role in neural progenitor cells (NPCs). Here, we investigated the role of CHL1 in the proliferation and differentiation of NPCs both in vivo and in vitro, and the possible mechanism involved. The number of BrdU-positive cells in the subventricular zone (SVZ) significantly increased in CHL1-/- mice compared with CHL1+/+ mice. Moreover, there were more Tuj1-positive cells in the cortical plate region in CHL1-/- mice than in CHL1+/+ controls. To further examine the function of CHL1 in the proliferation and differentiation of NPCs, NPCs from CHL1-/- mice versus littermate wild-type mice were isolated and cultured in vitro. NPCs derived from CHL1-/- mice showed increased proliferation and self-renewal ability compared with CHL1+/+ mice. In the course of differentiation, CHL1 deficiency enhanced neuronal differentiation in the absence of growth factors. Furthermore, CHL1 deficiency on the proliferation of NPCs is accompanied by means of enhanced activation of ERK1/2 mitogen-activated protein kinase (MAPK) and the inhibitor of ERK1/2 MAPK eliminates the effect of CHL1 deficiency on the proliferation of NPCs. Our results first describe the negative modulation of the proliferation and neuronal differentiation of NPCs by CHL1/ERK1/2 MAPK signaling.

TRIM32 Deficiency Impairs the Generation of Pyramidal Neurons in Developing Cerebral Cortex.

Excitatory-inhibitory imbalance (E/I) is a fundamental mechanism underlying autism spectrum disorders (ASD). TRIM32 is a risk gene genetically associated with ASD. The absence of TRIM32 causes impaired generation of inhibitory GABAergic interneurons, neural network hyperexcitability, and autism-like behavior in mice, emphasizing the role of TRIM32 in maintaining E/I balance, but despite the description of TRIM32 in regulating proliferation and differentiation of cultured mouse neural progenitor cells (NPCs), the role of TRIM32 in cerebral cortical development, particularly in the production of excitatory pyramidal neurons, remains unknown. The present study observed that TRIM32 deficiency resulted in decreased numbers of distinct layer-specific cortical neurons and decreased radial glial cell (RGC) and intermediate progenitor cell (IPC) pool size. We further demonstrated that TRIM32 deficiency impairs self-renewal of RGCs and IPCs as indicated by decreased proliferation and mitosis. A TRIM32 deficiency also affects or influences the formation of cortical neurons. As a result, TRIM32-deficient mice showed smaller brain size. At the molecular level, RNAseq analysis indicated reduced Notch signalling in TRIM32-deficient mice. Therefore, the present study indicates a role for TRIM32 in pyramidal neuron generation. Impaired generation of excitatory pyramidal neurons may explain the hyperexcitability observed in TRIM32-deficient mice.