Hye-Sun Kim’s research while affiliated with Gangnam Severance Hospital and other places

This retrospective study aimed to evaluate the difference in the temporomandibular joint (TMJ) space volume between the deviated (Dev) and non-deviated (NDev) side following transoral vertical ramus osteotomy (TOVRO) in patients with mandibular prognathism combined with asymmetry using reconstructed 3-dimensional images. Sixty joints from 30 patients who underwent TOVRO between January 2018 and December 2021 were included. Computed tomography (CT) or cone-beam CT was performed before surgery (T0), and 6 (T1) and 12 months postoperatively (T2). The volume of the overall joint space (Vjs) and its compartments (i.e., the anterior, posterior, medial, and lateral joint spaces) were calculated at each time point. A linear mixed model and repeated-measures covariance pattern with unstructured covariance were used. Vjs increased at T1 compared to T0 and decreased at T2 compared to T1 (p < 0.0001). Furthermore, the volume changes over time were statistically significant in all compartments (p < 0.05); however, there was no significant difference in the Vjs and its compartments between the Dev and NDev side over time (p > 0.05). Adjustments for sex and mandibular movements did not affect the results. This study can provide the basis in TMJ spatial change and predicting the prognosis after TOVRO in facial asymmetry.

This study describes the effects of translationally controlled tumor protein (TCTP) on mice with memory impairment caused by scopolamine (SCO) administration. Specifically, memory functions and expression levels of hippocampal synaptic proteins in 7- to 12-month-old SCO-treated wild-type (WT-SCO) mice were compared to those of TCTP-overexpressing (TG) and TCTP knocked-down (KD) mice similarly treated with SCO. Passive-avoidance tasks were performed with WT, TG, and KD mice for four weeks after intraperitoneal injection of SCO or saline followed by an acquisition test. After completing behavioral studies, hippocampi of all mice groups were collected and their synaptic protein contents were subjected to Western blotting or immunohistochemical analyses, and compared with those of 5x familial Alzheimer's disease (5xFAD) mice and postmortem AD patients. Results of passive avoidance tests revealed that SCO-induced memory impairment was repaired in TCTP-TG mice, but not in TCTP-KD mice. Hippocampal expression levels of synaptophysin, synapsin-1, and PSD-95 were increased in TCTP-TG mice treated with SCO (TG-SCO) but decreased in TCTP-KD mice treated with SCO (KD-SCO). Decreased levels of TCTP, synaptophysin, and PSD-95 were also found in hippocampi of 5xFAD mice and AD patients. Expression levels of p-CREB/CREB and brain-derived neurotrophic factor (BDNF) in TCTP-TG and TG-SCO mice were similar to or increased compared to those in WT mice, but decreased in TCTP-KD and KD-SCO mice. BDNF immunoreactivity was restored in CA1 regions of hippocampi of TG-SCO mice, but not in KD-SCO mice. These results suggest that TCTP can restore damaged memory in mice possibly through restored synaptic protein expression.

Background Aducanumab (Adu), which is a human IgG1 monoclonal antibody that targets oligomer and fibril forms of beta-amyloid, has been reported to reduce amyloid pathology and improve impaired cognition after administration of a high dose (10 mg/kg) of the drug in Alzheimer’s disease (AD) clinical trials. The purpose of this study was to investigate the effects of a lower dose of Adu (3 mg/kg) with enhanced delivery via focused ultrasound (FUS) in an AD mouse model. Methods The FUS with microbubbles opened the blood–brain barrier (BBB) of the hippocampus for the delivery of Adu. The combined therapy of FUS and Adu was performed three times in total and each treatment was performed biweekly. Y-maze test, Brdu labeling, and immunohistochemical experimental methods were employed in this study. In addition, RNA sequencing and ingenuity pathway analysis were employed to investigate gene expression profiles in the hippocampi of experimental animals. Results The FUS-mediated BBB opening markedly increased the delivery of Adu into the brain by approximately 8.1 times in the brains. The combined treatment induced significantly less cognitive decline and decreased the level of amyloid plaques in the hippocampi of the 5×FAD mice compared with Adu or FUS alone. Combined treatment with FUS and Adu activated phagocytic microglia and increased the number of astrocytes associated with amyloid plaques in the hippocampi of 5×FAD mice. Furthermore, RNA sequencing identified that 4 enriched canonical pathways including phagosome formation, neuroinflammation signaling, CREB signaling and reelin signaling were altered in the hippocami of 5×FAD mice receiving the combined treatment. Conclusion In conclusion, the enhanced delivery of a low dose of Adu (3 mg/kg) via FUS decreases amyloid deposits and attenuates cognitive function deficits. FUS-mediated BBB opening increases adult hippocampal neurogenesis as well as drug delivery. We present an AD treatment strategy through the synergistic effect of the combined therapy of FUS and Adu.

Purpose: In Alzheimer disease (AD), brain regions such as the cortex and the hippocampus show abundant amyloid load which correlates with cognitive function decline. Prior to the significant development of AD pathophysiology, patients report the manifestation of neuropsychiatric symptoms, indicating a functional interplay between basal ganglia structures and hippocampal regions. Zinc finger and BTB domain-containing protein 16 (ZBTB16) is a transcription factor that controls the expression of downstream genes and the involvement of ZBTB16 in the striatum undergoing pathological aging in AD and the resulting behavioral phenotypes has not yet been explored. Methods: To study molecular alterations in AD pathogenesis, we analyzed the brain from amyloid precursor protein (APP)/ presenilin 1 (PS1) transgenic mice. The molecular changes in the striatal region of the brain were analyzed via the immunoblotting, and the quantitative RNA sequencing. The cognitive impairments of APP/PS1 mice were assessed via 3 behavioral tests: 3-chamber test, Y-maze test, and noble object recognition test. And multielectrode array experiments for the analysis of the neuronal activity of the striatum in APP/PS1 mice was performed. Results: We found that the alteration in ZBTB16 levels that occurred in the early ages of the pathologically aging striatum coalesces with the disruption of transcriptional dysregulation while causing social memory deficits, anxiety-like behavior. The early ZBTB16 knockdown treatment in the striatum of APP/PS1 mice rescued cognition that continued into later age. Conclusion: This study demonstrates that perturbation of transcriptional regulation of ZBTB16 during pathological aging may influence cognitive impairments and reveals a potent approach to targeting the transcriptional regulation of the striatum for the treatment of AD.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that exhibits neurobehavioral deficits characterized by abnormalities in social interactions, deficits in communication as well as restricted interests, and repetitive behaviors. The basal ganglia is one of the brain regions implicated as dysfunctional in ASD. In particular, the defects in corticostriatal function have been reported to be involved in the pathogenesis of ASD. Surface deformation of the striatum in the brains of patients with ASD and their correlation with behavioral symptoms was reported in magnetic resonance imaging (MRI) studies. We demonstrated that prenatal valproic acid (VPA) exposure induced synaptic and molecular changes and decreased neuronal activity in the striatum. Using RNA sequencing (RNA-Seq), we analyzed transcriptome alterations in striatal tissues from 10-week-old prenatally VPA-exposed BALB/c male mice. Among the upregulated genes, Nurr1 was significantly upregulated in striatal tissues from prenatally VPA-exposed mice. Viral knockdown of Nurr1 by shRNA significantly rescued the reduction in dendritic spine density and the number of mature dendritic spines in the striatum and markedly improved social deficits in prenatally VPA-exposed mice. In addition, treatment with amodiaquine, which is a known ligand for Nurr1, mimicked the social deficits and synaptic abnormalities in saline-exposed mice as observed in prenatally VPA-exposed mice. Furthermore, PatDp+/− mice, a commonly used ASD genetic mouse model, also showed increased levels of Nurr1 in the striatum. Taken together, these results suggest that the increase in Nurr1 expression in the striatum is a mechanism related to the changes in synaptic deficits and behavioral phenotypes of the VPA-induced ASD mouse model.

Background Aducanumab (Adu), which is a human IgG1 monoclonal antibody that targets oligomer and fibril forms of beta-amyloid (Aβ), has been reported to reduce amyloid pathology and improve impaired cognition after the administration of a high dose (10 mg/kg) of the drug in Alzheimer’s disease (AD) clinical trials. The purpose of this study is to investigate the effects of a lower dose of Adu (3mg/kg) with enhanced delivery via focused ultrasound (FUS) in an AD mouse model. Methods The FUS with microbubbles opened the blood-brain barrier of the hippocampus for the delivery of Aducanumab. Combined therapy of FUS and Aducanumab was performed three times in total and each treatment was performed biweekly. Y-maze test, Brdu labeling, immunohistochemical experimental methods were employed in this study. In addition, RNA sequencing and ingenuity pathway analysis were employed to investigate gene expression profiles in the hippocampi of experimental animals. Results The combined treatment with FUS markedly increased the delivery of Adu into the brain by approximately 8.1 times in the brains. The combined treatment significantly restored cognitive impairment and decreased the level of amyloid plaques in the hippocampi of 5xFAD mice compared with Adu or FUS alone. The combined treatment with FUS and Adu increased reactive microglia and astrocytes associated with amyloid plaques in the hippocampi of 5xFAD mice. Furthermore, RNA sequencing identified 4 enriched canonical pathways such as phagosome formation, neuroinflammation signaling, CREB signaling and reelin signaling was altered in the hippocami of 5xFAD given the combined treatment. Conclusion In conclusion, the enhanced delivery of a low dose of Aducanumab via FUS decreased amyloid deposits and restored cognitive function. This study provides better insight into establishing a solid therapeutic strategy for the treatment of AD as well as other neurodegenerative diseases.

Background: The diverse roles of ubiquitously present translationally controlled tumor protein (TCTP) have been well delineated in several organs, but its possible function in the brain, especially with regard to memory function, has not received much attention. This study describes the effects of TCTP on mice with memory impaired by scopolamine (SCO) administration. Specifically, the memory and synaptic functions of 7- and 12-month-old SCO-treated wild mice (WT) were compared with those of TCTP-overexpressing (TG) and TCTP knocked down (KD) mice. Methods: Passive-avoidance tasks were performed on WT, TG and KD mice for 4 weeks after intraperitoneal injection with SCO (1 mg/kg) or saline (CON). After completion of the behavioral studies, the hippocampi were collected and their PSD-95, synapsin-1 and synaptophysin contents analyzed by western blocking and immunohistochemical analyses, and compared with those of 5xfamilial Alzheimer's disease (5xFAD) mice and postmortem AD patients. Results: The SCO-induced memory impairment was restored in TCTP-TG to that of WT level, but not in KD. Hippocampal expression of PSD-95, synapsin-1, and synaptophysin was increased in TG-SCO but decreased in KD-SCO mice. The decreased levels of TCTP, PSD-95, and synaptophysin were also found in the hippocampi of 5xFAD mice and AD patients. PSD-95 immunoreactivity increased particularly in dentate gyrus and CA1 in TCTP-TG, but reduced in KD. The p-CREB/CREB and brain-derived neurotrophic factor (BDNF) expressions also increased in TCTP-TG but dramatically decreased in KD. Conclusion: TCTP restores damaged memory in mice possibly by increasing synaptic function. Keywords TCTP, transgenic, knockdown, scopolamine-induced dementia, memory, synaptic function, PSD-95, synaptophysin, synapsin-1, CREB, BDNF

Rationale: Cerebral Methyl-CpG binding Protein 2 (MeCP2) is involved in several psychiatric disorders that are concomitant with cognitive dysfunction. However, the regulatory function of striatal MeCP2 and its association with Alzheimer's disease (AD) has been largely neglected due to the absence of amyloid plaque accumulation in the striatal region until the later stages of AD progression. Considerable evidence indicates that neuropsychiatric symptoms related to cognitive decline are involved with striatal dysfunction. To this respect, we investigated the epigenetic function of striatal MeCP2 paralleling the pathogenesis of AD. Methods: We investigated the brain from amyloid precursor protein (APP)/presenilin1 (PS1) transgenic mice and postmortem brain samples from normal subjects and AD patients. The molecular changes in the brain, particularly in the striatal regions, were analyzed with thioflavin S staining, immunohistochemistry, immunoblotting, and MeCP2 chromatin immunoprecipitation sequencing (ChIP-seq). The cognitive function of APP/PS1 mice was assessed via three behavioral tests: 3-chamber test (3CT), Y-maze test (YMT), and passive avoidance test (PA). A multi-electrode array (MEA) was performed to analyze the neuronal activity of the striatum in APP/PS1 mice. Results: Striatal MeCP2 expression was increased in the younger (6 months) and older (10 months) ages of APP/PS1 mice, and the genome-wide occupancy of MeCP2 in the younger APP/PS1 showed dysregulated binding patterns in the striatum. Additionally, we confirmed that APP/PS1 mice showed behavioral deficits in multiple cognitive behaviors. Notably, defective cognitive phenotypes and abnormal neuronal activity in old APP/PS1 mice were rescued through the knock-down of striatal MeCP2. Conclusion: We found that the MeCP2-mediated dysregulation of the epigenome in the striatum is linked to the defects in cognitive behavior and neuronal activity in the AD animal model, and that this alteration is initiated even in the very early stages of AD pathogenesis. Together, our data indicates that MeCP2 may be a potential target for the diagnosis and treatment of AD at asymptomatic and symptomatic stages.

The morphological dynamics of astrocytes are altered in the hippocampus during memory induction. Astrocyte–neuron interactions on synapses are called tripartite synapses. These control the synaptic function in the central nervous system. Astrocytes are activated in a reactive state by STAT3 phosphorylation in 5XFAD mice, an Alzheimer’s disease (AD) animal model. However, changes in astrocyte–neuron interactions in reactive or resting-state astrocytes during memory induction remain to be defined. Here, we investigated the time-dependent changes in astrocyte morphology and the number of astrocyte–neuron interactions in the hippocampus over the course of long-term memory formation in 5XFAD mice. Hippocampal-dependent long-term memory was induced using a contextual fear conditioning test in 5XFAD mice. The number of astrocytic processes increased in both wild-type and 5XFAD mice during memory formation. To assess astrocyte–neuron interactions in the hippocampal dentate gyrus, we counted the colocalization of glial fibrillary acidic protein and postsynaptic density protein 95 via immunofluorescence. Both groups revealed an increase in astrocyte–neuron interactions after memory induction. At 24 h after memory formation, the number of tripartite synapses returned to baseline levels in both groups. However, the total number of astrocyte–neuron interactions was significantly decreased in 5XFAD mice. Administration of Stattic, a STAT3 phosphorylation inhibitor, rescued the number of astrocyte–neuron interactions in 5XFAD mice. In conclusion, we suggest that a decreased number of astrocyte–neuron interactions may underlie memory impairment in the early stages of AD.

Ketamine is a dissociative anesthetic and a non-competitive NMDAR antagonist. At subanesthetic dose, ketamine can relieve pain and work as a fast-acting antidepressant, but the underlying molecular mechanism remains elusive. This study aimed to investigate the mode of action underlying the effects of acute subanesthetic ketamine treatment by bioinformatics analyses of miRNAs in the medial prefrontal cortex of male C57BL/6J mice. Gene Ontology and KEGG pathway analyses of the genes putatively targeted by ketamine-responsive prefrontal miRNAs revealed that acute subanesthetic ketamine modifies ubiquitin-mediated proteolysis. Validation analysis suggested that miR-148a-3p and miR-128-3p are the main players responsible for the subanesthetic ketamine-mediated alteration of ubiquitin-mediated proteolysis through varied regulation of ubiquitin ligases E2 and E3. Collectively, our data imply that the prefrontal miRNA-dependent modulation of ubiquitin-mediated proteolysis is at least partially involved in the mode of action by acute subanesthetic ketamine treatment.