Schizophrenia (SZ) stands as a severe psychiatric disorder. This study applied diffusion tensor imaging (DTI) data in conjunction with graph neural networks to distinguish SZ patients from normal controls (NCs) and showcases the superior performance of a graph neural network integrating combined fractional anisotropy and fiber number brain network features, achieving an accuracy of 73.79% in distinguishing SZ patients from NCs. Beyond mere discrimination, our study delved deeper into the advantages of utilizing white matter brain network features for identifying SZ patients through interpretable model analysis and gene expression analysis. These analyses uncovered intricate interrelationships between brain imaging markers and genetic biomarkers, providing novel insights into the neuropathological basis of SZ. In summary, our findings underscore the potential of graph neural networks applied to multimodal DTI data for enhancing SZ detection through an integrated analysis of neuroimaging and genetic features.
Humans ; Schizophrenia/pathology* ; Diffusion Tensor Imaging/methods* ; Male ; Female ; Adult ; Brain/metabolism* ; Young Adult ; Middle Aged ; White Matter/pathology* ; Gene Expression ; Nerve Net/diagnostic imaging* ; Graph Neural Networks

OBJECTIVES: To observe the reparative effects of human umbilical cord mesenchymal stem cell (hUC-MSC) transplantation on white matter injury (WMI) in neonatal rats and explore its mechanism through the nuclear factor-kappa B (NF-κB) signaling pathway mediated by microglial cells. METHODS: Sprague-Dawley rats, aged 2 days, were randomly divided into three groups: sham-operation,WMI, and hUC-MSC (n=18 each). Fourteen days after modeling, hematoxylin-eosin staining was used to observe pathological changes in the white matter, and immunofluorescence staining was used to measure the expression level of ionized calcium-binding adapter molecule 1 (Iba1). Western blotting was used to measure the protein expression levels of inhibitory subunit of nuclear factor-kappa B alpha (IκBα), phosphorylated IκBα (p-IκBα), phosphorylated NF-κB p65 (p-NF-κB p65), myelin basic protein (MBP), and neuron-specific nuclear protein (NeuN). Quantitative real-time PCR was used to assess the mRNA expression levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), MBP, and NeuN. Immunohistochemistry was used to measure the protein expression levels of MBP and NeuN. On day 28, the Morris water maze test was used to evaluate spatial cognitive ability. RESULTS: Fourteen days after modeling, the sham-operation group exhibited intact white matter structure with normal cell morphology and orderly nerve fiber arrangement. In the WMI group, large-scale cell degeneration and necrosis were observed, and nerve fiber arrangement was disordered. The hUC-MSC group showed relatively normal cell morphology and more orderly nerve fibers. Compared with the sham-operation group, the WMI group had significantly higher proportions of Iba1-positive cells, increased protein levels of p-IκBα and p-NF-κB p65, and higher mRNA levels of TNF-α and IL-1β. The protein expression of IκBα and the positive expression of MBP and NeuN, as well as their protein and mRNA levels, were significantly reduced in the WMI group (P<0.05). Compared with the WMI group, the hUC-MSC group showed reduced proportions of Iba1-positive cells, decreased protein levels of p-IκBα and p-NF-κB p65, and lower mRNA levels of TNF-α and IL-1β. Furthermore, IκBα protein expression and MBP and NeuN expression (both at the protein and mRNA levels) were significantly increased in the hUC-MSC group (P<0.05). On day 28, the Morris water maze results showed that compared with the sham-operation group, the WMI group had significantly longer escape latency and fewer platform crossings (P<0.05). In contrast, the hUC-MSC group had significantly shorter escape latency and more platform crossings than the WMI group (P<0.05). CONCLUSIONS hUC-MSC transplantation can repair WMI in neonatal rats, promote the maturation of oligodendrocytes, and support neuronal survival, likely by inhibiting activation of the NF-κB signaling pathway mediated by microglial cells.
Animals ; Rats, Sprague-Dawley ; White Matter/metabolism* ; Rats ; Signal Transduction ; Mesenchymal Stem Cell Transplantation ; Humans ; NF-kappa B/metabolism* ; Animals, Newborn ; Umbilical Cord/cytology* ; Male ; NF-KappaB Inhibitor alpha/metabolism* ; I-kappa B Proteins/genetics* ; Microfilament Proteins/analysis* ; Calcium-Binding Proteins/metabolism* ; Female

Chronic cerebral hypoperfusion leads to white matter injury (WMI), which subsequently causes neurodegeneration and even cognitive impairment. However, due to the lack of treatment specifically for WMI, novel recognized and effective therapeutic strategies are urgently needed. In this study, we found that honokiol and magnolol, two compounds derived from Magnolia officinalis, significantly facilitated the differentiation of primary oligodendrocyte precursor cells (OPCs) into mature oligodendrocytes, with a more prominent effect of the former compound. Moreover, our results demonstrated that honokiol treatment improved myelin injury, induced mature oligodendrocyte protein expression, attenuated cognitive decline, promoted oligodendrocyte regeneration, and inhibited astrocytic activation in the bilateral carotid artery stenosis model. Mechanistically, honokiol increased the phosphorylation of serine/threonine kinase (Akt) and mammalian target of rapamycin (mTOR) by activating cannabinoid receptor 1 during OPC differentiation. Collectively, our study indicates that honokiol might serve as a potential treatment for WMI in chronic cerebral ischemia.
Magnolia ; White Matter ; Brain Ischemia/metabolism* ; Oligodendroglia/metabolism*

Insufficient remyelination due to impaired oligodendrocyte precursor cell (OPC) differentiation and maturation is strongly associated with irreversible white matter injury (WMI) and neurological deficits. We analyzed whole transcriptome expression to elucidate the potential role and underlying mechanism of action of lipocalin-2 (LCN2) in OPC differentiation and WMI and identified the receptor SCL22A17 and downstream transcription factor early growth response protein 1 (EGR1) as the key signals contributing to LCN2-mediated insufficient OPC remyelination. In LCN-knockdown and OPC EGR1 conditional-knockout mice, we discovered enhanced OPC differentiation in developing and injured white matter (WM); consistent with this, the specific inactivation of LCN2/SCl22A17/EGR1 signaling promoted remyelination and neurological recovery in both atypical, acute WMI due to subarachnoid hemorrhage and typical, chronic WMI due to multiple sclerosis. This potentially represents a novel strategy to enhance differentiation and remyelination in patients with white matter injury.
Mice ; Animals ; Remyelination/physiology* ; Oligodendrocyte Precursor Cells/metabolism* ; White Matter ; Subarachnoid Hemorrhage/metabolism* ; Lipocalin-2/metabolism* ; Early Growth Response Protein 1/metabolism* ; Oligodendroglia/metabolism* ; Mice, Knockout ; Cell Differentiation/physiology* ; Brain Injuries/metabolism*

OBJECTIVE: To correlate the resting metabolism of hand knob and hand function after stroke, diffuse tensor tractography (DTT) and ¹⁸F-fluorodeoxyglucose position emission tomography (¹⁸F-FDG PET) were used to evaluate constructible state of white matter tract and metabolic state of gray matter, respectively. METHODS: A total of 17 patients were included in the study, who had suffered a stroke with hand weakness, after a stroke. They underwent diffusion tensor analysis and FDG PET in the subacute period. The ratio of both hemisphere parameters in voxel number of fibers, fractional anisotropy (FA) and apparent diffusion coefficient obtained by corticospinal tract as constructed by DTT, and the metabolism of hand knob area on cerebral cortex obtained from ¹⁸F-FDG PET were calculated. Hand movement scale was evaluated on the day of FDG PET or tractography, and at 6 months after onset. RESULTS: Difference of FA in DTT between both hemispheres and hand knob metabolism in FDG PET significantly correlated with the hand movement scale at the subacute stage and 6 months after onset. However, the difference of both hemispheres in DTT and metabolism of hand knob area was not significant. CONCLUSION: Resting metabolism on hand knob in FDG PET correlated with hand function after stroke.
Anisotropy ; Cerebral Cortex ; Diffusion ; Diffusion Tensor Imaging ; Gray Matter ; Hand* ; Humans ; Metabolism* ; Positron-Emission Tomography ; Pyramidal Tracts* ; Stroke* ; White Matter

OBJECTIVETo explore the impacts of erythropoietin on vascular endothelial growth factor receptor 2 (VEGFR2) by the extracellular signal-regulated kinase (ERK) signaling pathway in a neonatal rat model of periventricular white matter damage.

METHODSAll of postnatal day 4 rats were randomized into three groups: the sham group [without hypoxia-ischemia (HI)], the HI group (HI with saline administration), and the erythropoietin (EPO) group [HI with recombinant human erythropoietin (rh-EPO) administration]. Rat pups underwent permanent ligation of the right common carotid artery, followed by 6% O2 for 2 hours or sham operation and normoxic exposure. Immediately after the HI, rats received a single intraventricular injection of rh-EPO (0.6 IU/g body mass) or saline. ERK and phosphorylation-ERK were examined at 60 minutes and 90 minutes after operation, and VEGFR2 were detected at 2 and 4 days after operation by using Western blot.

RESULTSAt 60 minutes and 90 minutes after operation, the proteins of phosphorylation-ERK were significantly higher in HI rats than in the sham rats and significantly higher in HI+EPO rats than in the HI rats (P<0.05). Two days after operation, VEGFR2 was not significantly different between sham and HI rats. However, the proteins of VEGFR2 were increased after administration of rh-EPO (P<0.05). Four days after operation, the proteins of VEGFR2 were significantly higher in HI rats than in the sham rats and significantly higher in HI+EPO rats than in the HI rats (P<0.05).

CONCLUSIONEPO may regulate VEGFR2 expression by affecting the intracranial ERK signaling pathways.

Animals ; Animals, Newborn ; Disease Models, Animal ; Erythropoietin ; pharmacology ; Humans ; Hypoxia-Ischemia, Brain ; physiopathology ; MAP Kinase Signaling System ; Phosphorylation ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins ; pharmacology ; Vascular Endothelial Growth Factor Receptor-2 ; metabolism ; White Matter ; physiopathology

OBJECTIVETo investigate the effect of γ-secretase inhibitor (N-[N-(3,5-difluorophenacetyl)-l -alanyl]-S-phenylglycine t-butyl ester, DAPT) on hyperoxia-induced brain white matter injury in mice.

MWTHODSThree-day-old C57BL/10J mouse pups were divided into air control (C) group, control+DAPT (10 mg/kg, injected intraperitoneally) group, hyperoxia group (exposed to 80% oxygen for 48 h), and hyperoxia+DAPT group. The brain and body weights of the mice were measured at postnatal days 3, 5, 12, and 28. Real-time PCR was used to detect Notch intracellular domain (NICD) mRNA expression in the brain after modeling, and the expressions of NG2 and myelin basic protein (MBP) were detected by double-labeled immunofluorescence assay to verify the oligdendrocycle type at postnatal day 12. The mice in each group were bred until postnatal day 28 for Morris water maze test.

RESULTSThe brain and body weights were significantly decreased in mice in hyperoxia group compared to the control mice, but increased significantly after DAPT treatment (P<0.05). Real-time PCR showed that a 48-hour hyperoxia exposure significantly increased NICD mRNA expression in the brain (P<0.05), which was decreased by co-treatment by DAPT (P<0.05). Hyperoxia also resulted in enhanced NG2 expression and lowered MBP expression in the brain (P<0.05). Compared with the control mice, the mice exposed to hyperoxia showed prolonged escape latency (P<0.05) and spent less time in the target quadrant with a lowered number of passing through the virtual platform (P<0.05). All these parameters were significantly improved by co-treatment with DAPT.

CONCLUSIONSpecific inhibition of Notch signaling pathway activation in the brain by the γ-secretase inhibitor DAPT can ameliorate white matter injury and learning and memory impairment in newborn mice with hyperoxia exposure.

Amyloid Precursor Protein Secretases ; antagonists & inhibitors ; Animals ; Body Weight ; Brain ; metabolism ; pathology ; Dipeptides ; pharmacology ; Hyperoxia ; physiopathology ; Mice ; Mice, Inbred C57BL ; Mice, Inbred Strains ; Organ Size ; Receptors, Notch ; metabolism ; Signal Transduction ; White Matter ; pathology

We compared the predictive ability of the various neuroimaging tools and determined the most cost-effective, non-invasive Alzheimer's disease (AD) prediction model in mild cognitive impairment (MCI) individuals. Thirty-two MCI subjects were evaluated at baseline with [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET), MRI, diffusion tensor imaging (DTI), and neuropsychological tests, and then followed up for 2 yr. After a follow up period, 12 MCI subjects converted to AD (MCIc) and 20 did not (MCInc). Of the voxel-based statistical comparisons of baseline neuroimaging data, the MCIc showed reduced cerebral glucose metabolism (CMgl) in the temporo-parietal, posterior cingulate, precuneus, and frontal regions, and gray matter (GM) density in multiple cortical areas including the frontal, temporal and parietal regions compared to the MCInc, whereas regional fractional anisotropy derived from DTI were not significantly different between the two groups. The MCIc also had lower Mini-Mental State Examination (MMSE) score than the MCInc. Through a series of model selection steps, the MMSE combined with CMgl model was selected as a final model (classification accuracy 93.8%). In conclusion, the combination of MMSE with regional CMgl measurement based on FDG-PET is probably the most efficient, non-invasive method to predict AD in MCI individuals after a two-year follow-up period.
Aged ; Alzheimer Disease/complications/*diagnosis ; Atrophy/pathology ; Biomarkers/blood ; Brain/*pathology ; Diffusion Tensor Imaging/methods ; Female ; Glucose/*metabolism ; Gray Matter/*pathology ; Humans ; Male ; Mild Cognitive Impairment/*diagnosis/etiology ; Neuroimaging/methods ; Positron-Emission Tomography/methods ; Reproducibility of Results ; Sensitivity and Specificity ; Severity of Illness Index ; White Matter/*pathology

OBJECTIVETo study the effects of caffeine citrate on myelin basic protein (MBP) expression in the cerebral white matter of neonatal rats with hypoxic-ischemic brain damage (HIBD) and the related mechanism.

METHODSForty-eight seven-day-old Sprague-Dawley neonatal rats were randomly assigned to 3 groups: sham operation (n=16), HIBD (n=16) and HIBD+caffeine citrate (n=16). The rats in the HIBD and HIBD+caffeine citrate groups were subjected to left common carotid artery ligation, and then were exposed to 80 mL/L oxygen and 920 mL/L nitrogen for 2 hours to induce HIBD. The rats in the sham operation group were only subjected to a sham operation, without the left common carotid artery ligation or hypoxia exposure. Caffeine citrate (20 mg/kg) was injected intraperitoneally before hypoxia ischemia (HI) and immediately, 24 hours, 48 hours and 72 hours after HI. The other two groups were injected intraperitoneally with an equal volume of normal saline at the corresponding time points. On postnatal day 12, the expression of MBP in the left subcortical white matter was detected by immunohistochemistry, and the levels of adenosine A1 receptor mRNA and A2a receptor mRNA in the left brain were detected by real-time PCR.

RESULTSThe expression of MBP in the left subcortical white matter in the HIBD group was lower than in the sham operation group (P<0.05). The MBP expression in the HIBD+caffeine citrate group was significantly higher than in the HIBD group, but was still lower than the sham operation group (P<0.05). Real-time PCR showed that the adenosine A1 receptor mRNA expression was significantly higher in the HIBD group than in the sham operation group, and it was significantly lower in the HIBD+caffeine citrate group than in the HIBD group (P<0.05).

CONCLUSIONSCaffeine citrate can improve brain white matter damage following HIBD in neonatal rats and the protection mechanism might be related with the down-regulation of adenosine A1 receptor expression.

Animals ; Animals, Newborn ; Caffeine ; pharmacology ; Citrates ; pharmacology ; Female ; Hypoxia-Ischemia, Brain ; drug therapy ; metabolism ; pathology ; Male ; Myelin Basic Protein ; analysis ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Receptor, Adenosine A1 ; genetics ; Receptor, Adenosine A2A ; genetics ; White Matter ; chemistry