RESUMO
BACKGROUND: Growing evidence points to the pivotal role of vitamin D in the pathophysiology and treatment of major depressive disorder (MDD). However, there is a paucity of longitudinal research investigating the effects of vitamin D supplementation on the brain of MDD patients. METHODS: We conducted a double-blind randomized controlled trial in 46 MDD patients, who were randomly allocated into either VD (antidepressant medication + vitamin D supplementation) or NVD (antidepressant medication + placebos) groups. Data from diffusion tensor imaging, resting-state functional MRI, serum vitamin D concentration, and clinical symptoms were obtained at baseline and after an average of 7 months of intervention. RESULTS: Both VD and NVD groups showed significant improvement in depression and anxiety symptoms but with no significant differences between the two groups. However, a greater increase in serum vitamin D concentration was found to be associated with greater improvement in depression and anxiety symptoms in VD group. More importantly, neuroimaging data demonstrated disrupted white matter integrity of right inferior fronto-occipital fasciculus along with decreased functional connectivity between right frontoparietal and medial visual networks after intervention in NVD group, but no changes in VD group. CONCLUSIONS: These findings suggest that vitamin D supplementation as adjunctive therapy to antidepressants may not only contribute to improvement in clinical symptoms but also help preserve brain structural and functional connectivity in MDD patients.
RESUMO
Background: Deep medullary vein (DMV) hypo-visibility is correlated with white matter hyperintensity (WMH), but the underlying causes remain unclear. This study aimed to explore the relationship between deep vein diameters and perivascular space (PVS) scores, and DMV hypo-visibility in the presence of WMH. Methods: This cross-sectional study prospectively analyzed the clinical and imaging data of 190 cerebral small vessel disease patients with WMH and 40 healthy controls from the Lishui Hospital of Traditional Chinese Medicine affiliated with Zhejiang Chinese Medical University. PVS scores ranging from 0 to 4 were determined according to the PVS counts in the basal ganglia area on T2-weighted magnetic resonance images; high-grade PVS was defined as a PVS score >1. The diameters of the deep cerebral veins, including the bilateral septal veins (SVs), thalamostriate veins (TSVs), lateral ventricular veins (LVVs), and internal cerebral veins, were measured using susceptibility weighted imaging (SWI). Left and right DMV scores, ranging from 0 to 9, were calculated based on the visibility of the DMV on SWI in the ipsilateral frontal, parietal, and occipital lobes. Results: The deep cerebral vein diameters, left and right DMV scores, and high-grade PVS differed between the healthy controls and WMH patients (P<0.05). Left DMV scores were independently associated with age {ß [95% confidence interval (CI)]: 0.050 (0.018, 0.082)}, high-grade PVS [ß (95% CI): 0.998 (0.262, 1.737)], and the diameters of the ipsilateral SVs [ß (95% CI): -1.114 (-1.754, -0.475)], SVs [ß (95% CI): -0.734 (-1.191, -0.277)], and LVVs [ß (95% CI): -0.921 (-1.567, -0.275)] [all false discovery rate (FDR)-corrected P<0.05]. Right DMV scores were independently associated with age [ß (95% CI): 0.071 (0.037, 0.105)], high-grade PVS [ß (95% CI): 0.873 (0.111, 1.635)], and the diameters of the ipsilateral SVs [ß (95% CI): -0.837 (-1.386, -0.289)], TSVs [ß (95% CI): -0.875 (-1.331, -0.419)], and LVVs [ß (95% CI): -1.813 (-2.484, -1.142)] (all FDR-corrected P<0.05). Conclusions: Decreased hypo-visibility of DMVs on SWI was associated with a higher age, the presence of high-grade PVS, and smaller diameters of the ipsilateral deep cerebral veins in individuals with WMH. Our findings provide novel insights into the probable mechanisms leading to high DMV scores.
RESUMO
Background and purpose: This study aimed to explore the correlation and causal relationship between fibrinogen, D-dimer, and the severity of cerebral white matter hyperintensity (MMH). Methods: A retrospective analysis of 120 patients with cerebral small vessel disease (CSVD) confirmed by head MRI attending the Third Affiliated Hospital of Beijing University of Traditional Chinese Medicine from August 2021 to February 2023 was performed. According to the Fazekas scale score, the patients were divided into 42 cases in the mild group, 44 cases in the moderate group, and 34 cases in the severe group. The levels of fibrinogen and D-dimer were compared among the three groups; the correlations between fibrinogen, D-dimer, and WMH severity were further analyzed; and independent risk factors for WMH severity were explored using the multivariate ordered logistic regression analysis. Furthermore, a two-sample Mendelian randomization (MR) analysis was performed to investigate the genetically predicted effect of fibrinogen and D-dimer on WMH. Results: As the severity of WMH increased, the levels of D-dimer and fibrinogen also gradually increased, and the results showed a positive correlational association, with significant differences within the groups (all p < 0.05); the multivariate ordered logistic regression model showed that after adjusting for the relevant covariates, D-dimer (OR = 5.998, 95% CI 2.213-16.252, p < 0.001) and fibrinogen (OR = 9.074, 95% CI 4.054-20.311, p < 0.001) remained independent risk factors for the severity of WMH. In the MR study, the random-effect inverse variance weighted (IVW) model showed that increased levels of genetically predicted D-dimer (OR, 1.01; 95% confidence interval 0.95-1.06; p = 0.81) and fibrinogen (OR, 1.91; 95% confidence interval 0.97-3.78; p = 0.06) were not associated with increased risk of WMH. The authors did not obtain strong evidence of a direct causal relationship between D-dimer, fibrinogen, and WMH. Conclusion: In this retrospective-based study, the authors found possible associations between D-dimer, fibrinogen, and WMH, but there was no obvious causal evidence. Further efforts are still needed to investigate the pathophysiology between D-dimer, fibrinogen, and WMH.
RESUMO
Vascular dementia (VaD) is the second most common type of dementia after Alzheimer's disease. In our previous studies, we showed that wheat bran extract (WBE) reduced white matter damage in a rat VaD model and improved memory in a human clinical trial. However, starch gelatinization made the large-scale preparation of WBE difficult. To simplify the manufacturing process and increase efficacy, we attempted to find a decoction containing an optimum ratio of wheat bran, sliced citrus peel, and sliced jujube (WCJ). To find an optimal ratio, the cell survival of C6 (rat glioma) cultured under hypoxic conditions (1% O2) was measured, and apoptosis was assessed. To confirm the efficacies of the optimized WCJ for VaD, pupillary light reflex, white matter damage, and the activation of astrocytes and microglia were assessed in a rat model of bilateral common carotid artery occlusion (BCCAO) causing chronic hypoperfusion. Using a combination of both searching the literature and cell survival experiments, we chose 6:2:1 as the optimal ratio of wheat bran to sliced citrus peel to sliced jujube to prepare WCJ. We showed that phytic acid contained only in wheat bran can be used as an indicator component for the quality control of WCJ. We observed in vitro that the WCJ treatment improved cell survival by reducing apoptosis through an increase in the Bcl-2/Bax ratio. In the BCCAO experiments, the WCJ-supplemented diet prevented astrocytic and microglial activation, mitigated myelin damage in the corpus callosum and optic tract, and, consequently, improved pupillary light reflex at dosages over 100 mg/kg/day. The results suggest that the consumption of WCJ can prevent VaD by reducing white matter damage, and WCJ can be developed as a safe, herbal medicine to prevent VaD.
RESUMO
To study the protective mechanism of acupuncture at "Jiangya Recipe" on chronic ischemic white matter injury in spontaneously hypertensive rats (SHR) and the regulation of Jun N-terminal kinase-N-methyl-D-aspartate receptor (JNK-NMDAR) loop. A hypertensive white matter injury model was established in 46 male SHR rats aged 11 weeks by bilateral common carotid artery tapering (SHR-2VGO). In the SHR sham operation group, only bilateral common carotid arteries were isolated and in the SHR-2VGO modeling group, 36 rats were used for microcoil spring clip implantation to narrow the common carotid arteries and then, after 2 weeks of modeling, rats with impaired motor function were removed, and SHR-2VGO rats with successful final models were randomly divided into the model group, JNK blocking group, and acupuncture group. The sham operation group, model group, and JNK blocking group underwent the same grasping fixation, and the acupuncture group received acupuncture at acupoints "Jiangya Fang" once daily. In the JNK blocker group, an injection cannula was implanted into the lateral ventricle and sp600125 was injected into the lateral ventricle at 4.5 ul/day for 4 weeks. One week after the end of the intervention, white matter lesions were detected by MRI DWI and T2 imaging, and the learning and memory ability of rats was tested by Y-Maze and Passive Avoidance. Myelin density was detected by luxol fast blue (LFB) staining, also axon arrangement, myelin integrity, and thickness of neurons were detected by electron microscopy; neuronal morphology and the number of Nissl bodies in the hippocampus were detected by Nissl staining, dendritic spine density changes were detected by Golgi staining, and JNK, NMDAR1, and N-methyl-D-receptor 2B (NMDAR2B) in DG, CA3 region of hippocampus were detected by immunohistochemistry, protein expression of p-JNK/JNK, p-NMDAR1/NMDAR1, NMDAR2B, GSK3ß protein expression in the fimbria of hippocampus was detected by Western blot. The Y maze test of SHR-2VGO+Acu and SHR-2VGO+ sp600125 group showed that the spontaneous alternating reaction rate increased significantly. At the same time, the incubation period increased significantly and the number of errors decreased significantly in Passive Avoidance. MRI T2WI showed that the white matter high signal of the corpus callosum, internal capsule and hippocampal fimbria in the SHR-2VGO+ sp600125 and SHR-2VGO+Acu groups was significantly lower than that in the SHR-2VGO model group, and the striatum and anterior commissure were not obvious. DWI showed that the SHR-2VGO model group had scattered high signal and limited diffusion movement in both the internal capsule and striatum, but the difference between groups was not obvious. Compared with SHR-2VGO rats, LFB staining of SHR-2VGO + sp600125 and SHR-2VGO +Acu groups showed significant relaxation of myelin porosity in corpus callosum, striatum, inner capsule, anterior commissure and hippocampal fimbria, and electron microscopy showed improved axonal myelin integrity and thickness in corpus callosum region. Also, the number of blue patchy Nissl bodies increased, and the number and complexity of dendritic spines increased significantly in Golgi staining. Immunohistochemical detection showed that JNK levels in DG and CA3 region were increased and NMDAR1 and NMDAR2B levels were decreased in SHR-2VGO+Acu and SHR-2VGO+ sp600125 groups. Meanwhile, protein expressions of GSK3ß, NMDAR1/p-NMDAR1 and NMDAR2B in fimbria of hippocampus were increased, and JNK/P-JNK protein expression decreased. Acupuncture can increase the density and thickness of myelin sheath in white matter areas of corpus callosum, anterior commissure and hippocampal fimbria, increase the number and length of hippocampal neuronal dendrites, and improve hypertensive white matter injury and cognitive decline through JNK-NMDAR pathway.
RESUMO
BACKGROUND AND AIM: Our previous study has revealed that OEA promotes motor function recovery in the chronic stage of ischemic stroke. However, the neuroprotective mechanism of OEA on motor function recovery after stroke still is unexplored. Therefore, the aim of this study was to explore the effects of OEA treatment on angiogenesis, neurogenesis, and white matter repair in the peri-infarct region after cerebral ischemia. EXPERIMENTAL PROCEDURE: The adult male rats were subjected to 2 h of middle cerebral artery occlusion. The rats were treated with 10 and 30 mg/kg OEA or vehicle daily starting from day 2 after ischemia induction until they were sacrificed. KEY RESULTS AND CONCLUSIONS: The results revealed that OEA increased cortical angiogenesis, neural progenitor cells (NPCs) proliferation, migration, and differentiation. OEA treatment enhanced the survival of newborn neurons and oligodendrogenesis, which eventually repaired the cortical neuronal injury and improved motor function after ischemic stroke. Meanwhile, OEA treatment promoted the differentiation of oligodendrocyte progenitor cells (OPCs) and oligodendrogenesis by activating the PPARα signaling pathway. Our results showed that OEA restores motor function by facilitating cortical angiogenesis, neurogenesis, and white matter repair in rats after ischemic stroke. Therefore, we demonstrate that OEA facilitates functional recovery after ischemic stroke and propose the hypothesis that the long-term application of OEA mitigates the disability after stroke.
Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Substância Branca , Ratos , Masculino , Animais , Substância Branca/metabolismo , PPAR alfa/metabolismo , Isquemia Encefálica/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Neurogênese , Diferenciação Celular , Oligodendroglia/metabolismoRESUMO
Background and aims: Recent preclinical studies and meta-analysis of clinical trials suggested that acupuncture may improve cognition in cerebral small vessel disease (CSVD). We investigated the cerebral hemodynamics of acupuncture in subjects with CSVD and compared its impact upon the cerebral hemodynamics in normal elderly subjects. Methods: 10 subjects with CSVD (CSVD group) and 10 aged-matched control subjects who had no or insignificant CSVD (control group) were recruited. A single session of acupuncture was applied for 30 min in both groups. We assessed the effect of our acupuncture intervention on cerebral hemodynamics by transcranial Doppler ultrasound (TCD). Peak systolic velocity (PSV) and pulsatility index (PI) of the middle cerebral artery (MCA) were assessed. Results: We observed that PSV increased by a maximum of 39% at 20 min (p<0.05), while there was no significant change in PI in the CSVD group during the acupuncture session. In the control group, although we observed no significant change in PSV during the acupuncture session, there was a significant decrease in PI by a maximum of 22% at 20 min (p<0.05). No adverse events were reported during or after the procedure. Conclusion: This study suggested that our acupuncture prescription was associated with an increase in cerebral blood flow in subjects with established moderate to severe CSVD yet without apparent impact on distal vascular resistance. While, in subjects with no or insignificant CSVD, it may reduce cerebral small vessel distal vascular resistance. A larger study is needed to confirm our findings.
RESUMO
OBJECTIVE: To determine whether transcutaneous auricular vagus nerve stimulation (taVNS) paired with twice daily bottle feeding increases the volume of oral feeds and white matter neuroplasticity in term-age-equivalent infants failing oral feeds and determined to need a gastrostomy tube. STUDY DESIGN: In this prospective, open-label study, 21 infants received taVNS paired with 2 bottle feeds for 2 - 3 weeks (2x). We compared 1) increase oral feeding volumes with 2x taVNS and previously reported once daily taVNS (1x) to determine a dose response, 2) number of infants who attained full oral feeding volumes, and 3) diffusional kurtosis imaging and magnetic resonance spectroscopy before and after treatment by paired t tests. RESULTS: All 2x taVNS treated infants significantly increased their feeding volumes compared with 10 days before treatment. Over 50% of 2x taVNS infants achieved full oral feeds but in a shorter time than 1x cohort (median 7 days [2x], 12.5 days [1x], P < .05). Infants attaining full oral feeds showed greater increase in radial kurtosis in the right corticospinal tract at the cerebellar peduncle and external capsule. Notably, 75% of infants of diabetic mothers failed full oral feeds, and their glutathione concentrations in the basal ganglia, a measure of central nervous system oxidative stress, were significantly associated with feeding outcome. CONCLUSIONS: In infants with feeding difficulty, increasing the number of daily taVNS-paired feeding sessions to twice-daily significantly accelerates response time but not the overall response rate of treatment. taVNS was associated with white matter motor tract plasticity in infants able to attain full oral feeds. TRIAL REGISTRATION: Clinicaltrials.gov (NCT04643808).
Assuntos
Estimulação Elétrica Nervosa Transcutânea , Estimulação do Nervo Vago , Substância Branca , Feminino , Humanos , Lactente , Substância Branca/diagnóstico por imagem , Estimulação do Nervo Vago/métodos , Gastrostomia , Estudos Prospectivos , Estimulação Elétrica Nervosa Transcutânea/métodos , Nervo Vago/fisiologiaRESUMO
In the present study, we explore the role of attachment for microstructural white matter (WM) changes in adolescents with anorexia nervosa (AN) before and after exposure to short-term and nutritional treatment. The case sample consisted of 22 female adolescent inpatients with AN (mean age: 15.2 ± 1.2 years) and the control sample were 18 gender-matched healthy adolescents (mean age: 16.8 ± 0.9 years). We performed a 3T MRI in the patient group during the acute state of AN and after weight restoration (duration: 2.6 ± 1 months) and compared the data to a healthy control group. To classify attachment patterns, we used the Adult Attachment Projective Picture System. In the patient sample, over 50% were classified with an attachment trauma/unresolved attachment status. Prior to treatment exposure, fractional anisotropy (FA) reductions and concordant mean diffusivity (MD) increases were evident in the fornix, the corpus callosum and WM regions of the thalamus, which normalized in the corpus callosum and the fornix post-therapy in the total patient sample (p < 0.002). In the acute state, patients with an attachment trauma demonstrated significant FA decreases compared to healthy controls, but no MD increases, in the corpus callosum and cingulum bilaterally, which remained decreased after therapy. Attachment patterns seem to be associated with region-specific changes of WM alterations in AN.
RESUMO
The Papez circuit, first proposed by James Papez in 1937, is a circuit believed to control memory and emotions, composed of the cingulate cortex, entorhinal cortex, parahippocampal gyrus, hippocampus, hypothalamus, and thalamus. Pursuant to James Papez, Paul Yakovlev and Paul MacLean incorporated the prefrontal/orbitofrontal cortex, septum, amygdalae, and anterior temporal lobes into the limbic system. Over the past few years, diffusion-weighted tractography techniques revealed additional limbic fiber connectivity, which incorporates multiple circuits to the already known complex limbic network. In the current review, we aimed to comprehensively summarize the anatomy of the limbic system and elaborate on the anatomical connectivity of the limbic circuits based on the published literature as an update to the original Papez circuit.
Assuntos
Giro do Cíngulo , Sistema Límbico , Humanos , Sistema Límbico/diagnóstico por imagem , Tonsila do Cerebelo , Tálamo , Hipocampo , Vias NeuraisRESUMO
BACKGROUND: Understanding the structural connectivity of white matter tracts (WMT) and their related functions is a prerequisite to implementing an "a la carte" "connectomic approach" to glioma surgery. However, accessible resources facilitating such an approach are lacking. Here we present an educational method that is readily accessible, simple, and reproducible that enables the visualization of WMTs on individual patient images via an atlas-based approach. METHODS: Our method uses the patient's own magnetic resonance imaging (MRI) images and consists of three main steps: data conversion, normalization, and visualization; these are accomplished using accessible software packages and WMT atlases. We implement our method on three common cases encountered in glioma surgery: a right supplementary motor area tumor, a left insular tumor, and a left temporal tumor. RESULTS: Using patient-specific perioperative MRIs with open-sourced and co-registered atlas-derived WMTs, we highlight the critical subnetworks requiring specific surgical monitoring identified intraoperatively using direct electrostimulation mapping with cognitive monitoring. The aim of this didactic method is to provide the neurosurgical oncology community with an accessible and ready-to-use educational tool, enabling neurosurgeons to improve their knowledge of WMTs and to better learn their oncologic cases, especially in glioma surgery using awake mapping. CONCLUSIONS: Taking no more than 3-5 min per patient and irrespective of their resource settings, we believe that this method will enable junior surgeons to develop an intuition, and a robust 3-dimensional imagery of WMT by regularly applying it to their cases both before and after surgery to develop an "a la carte" connectome-based perspective to glioma surgery.
Assuntos
Neoplasias Encefálicas , Conectoma , Glioma , Substância Branca , Humanos , Conectoma/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/patologia , Procedimentos Neurocirúrgicos/métodos , Glioma/diagnóstico por imagem , Glioma/cirurgia , Glioma/patologia , Substância Branca/patologia , Mapeamento Encefálico/métodos , Encéfalo/cirurgiaRESUMO
Ginkgo biloba L. leaf extract (GBE) has been added in many commercial herbal formulations such as EGb 761 and Shuxuening Injection to treat cardiovascular diseases and stroke worldwide. However, the comprehensive effects of GBE on cerebral ischemia remained unclear. Using a novel GBE (nGBE), which consists of all the compounds of traditional (t)GBE and one new compound, pinitol, we investigated its effect on inflammation, white matter integrity, and long-term neurological function in an experimental stroke model. Both transient middle cerebral artery occlusion (MCAO) and distal MCAO were conducted in male C57/BL6 mice. We found that nGBE significantly reduced infarct volume at 1, 3, and 14 days after ischemia. Sensorimotor and cognitive functions were superior in nGBE treated mice after MCAO. nGBE inhibited the release of IL-1ß in the brain, promoted microglial ramification, and regulated the microglial M1 to M2 phenotype shift at 7 days post injury. In vitro analyses showed that nGBE treatment reduced the production of IL-1ß and TNFα in primary microglia. Administration of nGBE also decreased the SMI-32/MBP ratio and enhanced myelin integrity, thus exhibiting improved white matter integrity at 28 days post stroke. These findings demonstrate that nGBE protects against cerebral ischemia by inhibiting microglia-related inflammation and promoting white matter repair, suggesting that nGBE is a promising therapeutic strategy for long-term recovery after stroke.
Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Substância Branca , Camundongos , Masculino , Animais , Ginkgo biloba , Doenças Neuroinflamatórias , Acidente Vascular Cerebral/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Microglia , Inflamação/tratamento farmacológicoRESUMO
Tai Chi Chuan (TCC) is an increasingly popular multimodal mind-body practice with potential cognitive benefits, yet the neurobiological mechanisms underlying these effects, particularly in relation to brain white matter (WM) microstructure, remain largely unknown. In this study, we used diffusion tensor imaging (DTI) and the attention network test (ANT) to compare 22 TCC practitioners and 18 healthy controls. We found extensive differences in fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) between the two groups. Specifically, TCC practitioners had significantly different diffusion metrics in the corticospinal tract (CST), fornix (FX)/stria terminalis (ST), and cerebral peduncle (CP). We also observed a significant correlation between increased FA values in the right CP and ANT performance in TCC practitioners. Our findings suggest that optimized regional WM microstructure may contribute to the complex information processing associated with TCC practice, providing insights for preventing cognitive decline and treating neurological disorders with cognitive impairment in clinical rehabilitation.
RESUMO
OBJECTIVE: The authors of this study aimed to define the microanatomy of the interthalamic adhesion (ITA) using microfiber dissection, magnetic resonance (MR) tractography, and histological analysis. METHODS: Sagittal, coronal, and axial MR images from 160 healthy individuals 2-82 years of age were examined. The relationships between age range and ITA morphology as well as between gender and ITA morphology were evaluated statistically. Among these 160 individuals, 100 who had undergone MR tractography were examined. In this group, the presence of fiber tracts in the ITA and the relationship with ITA morphological types were examined. Thirty formalin-fixed human cadaveric brains were also examined endoscopically, and 6 hemispheres were dissected from the medial to lateral and superior to inferior directions under the microscope. Sections taken from one of the brains with an ITA type 2 with both thalami were examined histologically. Anti-neurofilament antibody was used in the histological examination. RESULTS: Four morphological types of ITA were observed. Type 1 had an adhesion/adherent appearance, type 2 had a bridge/commissure appearance, type 3 showed no adhesion, and type 4 had a double bridge. Tractographic examination revealed that 28% had no fiber tract transition in the ITA, 21% had a significant transition, and 51% had an indistinct transition. Statistically, the presence of the ITA was significantly higher in the pediatric (age) and female (gender) groups. In specimens with ITAs of a bridge/commissure appearance (type 2), fiber tracts showed clear transitions between thalami. In type 1 (adherent/adhesive appearance), fiber tracts were observed within the ITA, but a reciprocal transition was unclear. Dissection showed that these fiber tracts in the ITA reach the nucleus accumbens, caudate nucleus, and frontoorbital region anteriorly and the lateral habenula and posterior commissure posteriorly. Some fibers also joined the ansa peduncularis. In histological studies, axonal fibers moving in the ITA were observed with anti-neurofilament antibody staining. CONCLUSIONS: This is the first study to demonstrate fiber tracts of the ITA through fiber dissection and transillumination techniques as well as radiological and histological study. Statistical data were obtained by comparing the morphological group with age and gender groups. The anatomy of this structure, which has been neglected for many years, was reexamined. This study showed that the ITA has fibers connecting different parts of the brain, in contrast to previous studies suggesting that it was a simple massa.
Assuntos
Tálamo , Substância Branca , Humanos , Feminino , Criança , Tálamo/cirurgia , Imageamento por Ressonância Magnética/métodos , Substância Branca/anatomia & histologia , Encéfalo , Dissecação/métodosRESUMO
BACKGROUND: The zona incerta (ZI) is involved in mediating survival behaviors and is connected to a wide range of cortical and subcortical structures, including key basal ganglia nuclei. Based on these connections and their links to behavioral modulation, we propose that the ZI is a connectional hub for mediating between top-down and bottom-up control and a possible target for deep brain stimulation for obsessive-compulsive disorder. METHODS: We analyzed the trajectory of cortical fibers to the ZI in nonhuman and human primates based on tracer injections in monkeys and high-resolution diffusion magnetic resonance imaging in humans. The organization of cortical and subcortical connections within the ZI were identified in the nonhuman primate studies. RESULTS: Monkey anatomical data and human diffusion magnetic resonance imaging data showed a similar trajectory of fibers/streamlines to the ZI. Prefrontal cortex/anterior cingulate cortex terminals all converged within the rostral ZI, with dorsal and lateral areas being most prominent. Motor areas terminated caudally. Dense subcortical reciprocal connections included the thalamus, medial hypothalamus, substantia nigra/ventral tegmental area, reticular formation, and pedunculopontine nucleus and a dense nonreciprocal projection to the lateral habenula. Additional connections included the amygdala, dorsal raphe nucleus, and periaqueductal gray. CONCLUSIONS: Dense connections with dorsal and lateral prefrontal cortex/anterior cingulate cortex cognitive control areas and the lateral habenula and the substantia nigra/ventral tegmental area, coupled with inputs from the amygdala, hypothalamus, and brainstem, suggest that the rostral ZI is a subcortical hub positioned to modulate between top-down and bottom-up control. A deep brain stimulation electrode placed in the rostral ZI would not only involve connections common to other deep brain stimulation sites but also capture several critically distinctive connections.
Assuntos
Estimulação Encefálica Profunda , Transtorno Obsessivo-Compulsivo , Zona Incerta , Animais , Humanos , Córtex Cerebral , Tálamo , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/terapiaRESUMO
AIMS: We aimed to examine the long-term benefits of mindfulness-based cognitive therapy (MBCT) on white matter plasticity in the cortical midline structures (CMS) for a period of 2 years in patients with panic disorder and the relationships between white matter changes in the CMS and severity of state and trait symptoms. METHODS: Seventy-one participants were enrolled and underwent diffusion tensor imaging at baseline and after 2 years (26 who received MBCT as an adjunct to pharmacotherapy [MBCT+PT], 20 treated with pharmacotherapy alone [PT-alone], and 25 healthy controls [HCs]). The severity of symptoms and fractional anisotropy (FA) in white matter regions underlying the CMS were assessed at baseline and 2-year follow-up. RESULTS: The MBCT+PT group showed better outcomes after 2 years than the PT-alone group. The groups showed different FA changes: the MBCT+PT group showed decreased FA in the left anterior cingulate cortex (ACC); the PT-alone group showed increased FA in the bilateral dorsomedial prefrontal cortex, posterior cingulate cortex (PCC), and precuneus. Decreased white matter FA in the ACC, PCC, and precuneus was associated with improvements in the severity of state and trait symptoms in patients with panic disorder. CONCLUSION: Alleviation of excessive white matter connectivity in the CMS after MBCT leads to improvements in clinical symptoms and trait vulnerability in patients with panic disorder. Our study provides new evidence for the long-term benefits of MBCT on white matter plasticity and its clinical applicability as a robust treatment for panic disorder.
Assuntos
Atenção Plena , Transtorno de Pânico , Substância Branca , Humanos , Transtorno de Pânico/diagnóstico por imagem , Transtorno de Pânico/terapia , Substância Branca/diagnóstico por imagem , Imagem de Tensor de Difusão , Estudos Longitudinais , AnisotropiaRESUMO
BACKGROUND: Structural network damage is a potentially important mechanism by which cerebral small vessel disease (SVD) can cause cognitive impairment. As a central hub of the structural network, the role of thalamus in SVD-related cognitive impairments remains unclear. We aimed to determine the associations between the structural alterations of thalamic subregions and cognitive impairments in SVD. METHODS: In this cross-sectional study, 205 SVD participants without thalamic lacunes from the third follow-up (2020) of the prospective RUN DMC study (Radboud University Nijmegen Diffusion Tensor and Magnetic Resonance Cohort), which was initiated in 2006, Nijmegen, were included. Cognitive functions included processing speed, executive function, and memory. Probabilistic tractography was performed from thalamus to 6 cortical regions, followed by connectivity-based thalamic segmentation to assess each thalamic subregion volume and connectivity (measured by mean diffusivity [MD] of the connecting white matter tracts) with the cortex. Least absolute shrinkage and selection operator regression analysis was conducted to identify the volumes or connectivity of the total thalamus and 6 thalamic subregions that have the strongest association with cognitive performance. Linear regression and mediation analyses were performed to test the association of least absolute shrinkage and selection operator-selected thalamic subregion volume or MD with cognitive performance, while adjusting for age and education. RESULTS: We found that higher MD of the thalamic-motor tract was associated with worse processing speed (ß=-0.27; P<0.001), higher MD of the thalamic-frontal tract was associated with worse executive function (ß=-0.24; P=0.001), and memory (ß=-0.28; P<0.001), respectively. The mediation analysis showed that MD of thalamocortical tracts mediated the association between corresponding thalamic subregion volumes and the cognitive performances in 3 domains. CONCLUSIONS: Our results suggest that the structural alterations of thalamus are linked to cognitive impairment in SVD, largely depending on the damage pattern of the white matter tracts connecting specific thalamic subregions and cortical regions.
Assuntos
Doenças de Pequenos Vasos Cerebrais , Disfunção Cognitiva , Substância Branca , Humanos , Imagem de Tensor de Difusão/métodos , Estudos Prospectivos , Estudos Transversais , Imageamento por Ressonância Magnética , Tálamo/patologia , Doenças de Pequenos Vasos Cerebrais/complicaçõesRESUMO
Despite associations of regular coffee consumption with fewer neurodegenerative disorders, its association with microstructural brain alterations is unclear. To address this, we examined the association of coffee consumption with brain MRI parameters representing vascular brain damage, neurodegeneration, and microstructural integrity in 2316 participants in the population-based Hamburg City Health Study. Cortical thickness and white matter hyperintensity (WMH) load were measured on FLAIR and T1-weighted images. Microstructural white matter integrity was quantified as peak width of skeletonized mean diffusivity (PSMD) on diffusion-weighted MRI. Daily coffee consumption was assessed in five groups (<1 cup, 1-2 cups, 3-4 cups, 5-6 cups, >6 cups). In multiple linear regressions, we examined the association between brain MRI parameters and coffee consumption (reference group <1 cup). After adjustment for covariates, 3-4 cups of daily coffee were associated with lower PSMD (p = 0.028) and higher cortical thickness (p = 0.015) compared to <1 cup. Moreover, 1-2 cups per day was also associated with lower PSMD (p = 0.022). Associations with WMH load or other groups of coffee consumption were not significant (p > 0.05). The findings indicate that regular coffee consumption is positively associated with microstructural white matter integrity and cortical thickness. Further research is necessary to determine longitudinal effects of coffee on brain microstructure.
Assuntos
Café , Substância Branca , Humanos , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , NeuroimagemRESUMO
OBJECTIVE: To observe the clinical efficacy of scalp acupuncture for spastic cerebral palsy (CP), and to explore its possible mechanism based on brain white matter fiber bundles, nerve growth related proteins and inflammatory cytokines. METHODS: A total of 90 children with spastic CP were randomly divided into a scalp acupuncture group and a sham scalp acupuncture group, 45 cases in each group. The children in the two groups were treated with conventional comprehensive rehabilitation treatment. The children in the scalp acupuncture group were treated with scalp acupuncture at the parietal temporal anterior oblique line, parietal temporal posterior oblique line on the affected side, and parietal midline. The children in the sham scalp acupuncture group were treated with scalp acupuncture at 1 cun next to the above point lines. The needles were kept for 30 min, once a day, 5 days a week, for 12 weeks. Before and after treatment, the diffusion tensor imaging (DTI) indexes of magnetic resonance (FA values of corticospinal tract [CST], anterior limb of internal capsule [ICAL], posterior limb of internal capsule [ICPL], genu of internal capsule [ICGL], genu of corpus callosum [GCC], body of corpus callosum [BCC] and splenium of corpus callosum [SCC]), serum levels of nerve growth related proteins (neuron-specific enolase [NSE], glial fibrillary acidic protein [GFAP], myelin basic protein [MBP], ubiquitin carboxy terminal hydrolase-L1 [UCH-L1]) and inflammatory cytokines (interleukin 33 [IL-33], tumor necrosis factor α [TNF-α]), cerebral hemodynamic indexes (mean blood flow velocity [Vm], systolic peak flow velocity [Vs] and resistance index [RI], pulsatility index [PI] of cerebral artery), surface electromyography (SEMG) signal indexes (root mean square [RMS] values of rectus femoris, hamstring muscles, gastrocnemius muscles, tibialis anterior muscles), gross motor function measure-88 (GMFM-88) score, modified Ashworth scale (MAS) score, ability of daily living (ADL) score were observed in the two groups. The clinical effect of the two groups was compared. RESULTS: After treatment, the FA value of each fiber bundle, Vm, Vs, GMFM-88 scores and ADL scores in the two groups were higher than those before treatment (P<0.05), and the above indexes in the scalp acupuncture group were higher than those in the sham scalp acupuncture group (P<0.05). After treatment, the serum levels of NSE, GFAP, MBP, UCH-L1, IL-33, TNF-α as well as RI, PI, MAS scores and RMS values of each muscle were lower than those before treatment (P<0.05), and the above indexes in the scalp acupuncture group were lower than those in the sham scalp acupuncture group (P<0.05). The total effective rate was 95.6% (43/45) in the scalp acupuncture group, which was higher than 82.2% (37/45) in the sham scalp acupuncture group (P<0.05). CONCLUSION: Scalp acupuncture could effectively treat spastic CP, improve the cerebral hemodynamics and gross motor function, reduce muscle tension and spasticity, and improve the ability of daily life. The mechanism may be related to repairing the white matter fiber bundles and regulating the levels of nerve growth related proteins and inflammatory cytokines.
Assuntos
Terapia por Acupuntura , Paralisia Cerebral , Criança , Humanos , Paralisia Cerebral/terapia , Interleucina-33 , Imagem de Tensor de Difusão/métodos , Couro Cabeludo , Espasticidade Muscular , Fator de Necrose Tumoral alfa , CitocinasRESUMO
At present, major depressive disorder (MDD) is highly prevalent with advanced neurological disorders as the main pathological manifestations. As the physiological function bearer of higher neural activity, gray matter has become the focus of MDD treatment. However, recent research has shown that white matter and gray matter are independent of each other in the central nervous system (CNS), and their functions are integrated and linked. In addition to gray matter damage, white matter damage is also the core driving event of disease progression and determines the outcome of MDD. At the treatment level, the current drug treatment of MDD mainly focuses on gray matter repair, while ignoring the importance of white matter integrity for the treatment of the disease, which has become the weakness of the current treatment of MDD. Traditional Chinese medicine (TCM) has good application potential in white matter repair. This paper elaborated on the following three aspects. ① The roles of white matter damage in the occurrence and development of MDD were summarized. ② The key link of white matter repair in MDD was elaborated with microglia microenvironment regulation as the entry point. ③ The application value of TCM in white matter repair in MDD was analyzed. This review aims to highlight the importance of white matter integrity in the treatment of MDD and is expected to expand the understanding dimension of the activity of related Chinese medicines in MDD from the perspective of white matter repair and analyze its potential application value.