1.A Comprehensive Overview of the Role of Visual Cortex Malfunction in Depressive Disorders: Opportunities and Challenges.
Fangfang WU ; Qingbo LU ; Yan KONG ; Zhijun ZHANG
Neuroscience Bulletin 2023;39(9):1426-1438
Major depressive disorder (MDD) is a highly heterogeneous mental disorder, and its complex etiology and unclear mechanism are great obstacles to the diagnosis and treatment of the disease. Studies have shown that abnormal functions of the visual cortex have been reported in MDD patients, and the actions of several antidepressants coincide with improvements in the structure and synaptic functions of the visual cortex. In this review, we critically evaluate current evidence showing the involvement of the malfunctioning visual cortex in the pathophysiology and therapeutic process of depression. In addition, we discuss the molecular mechanisms of visual cortex dysfunction that may underlie the pathogenesis of MDD. Although the precise roles of visual cortex abnormalities in MDD remain uncertain, this undervalued brain region may become a novel area for the treatment of depressed patients.
Humans
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Depressive Disorder, Major/pathology*
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Brain/pathology*
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Antidepressive Agents/therapeutic use*
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Visual Cortex/pathology*
2.Chronic administration of Liu Wei Dihuang protects rat's brain against D-galactose-induced impairment of cholinergic system.
Wei-Wei ZHANG ; Qi-Xin SUN ; Yin-Hui LIU ; Wei GAO ; Yan-Hai LI ; Kun LU ; Zhuo WANG
Acta Physiologica Sinica 2011;63(3):245-255
This study was aimed to investigate the protective effect of Liu Wei Dihuang (LWDH) against D-galactose (D-gal)-induced brain injury in rats and the existence of sex-dependent differences in LWDH protection. Sixty-four rats evenly composed of males and females were randomly assigned into 4 groups (n = 8): normal saline (NS) + NS (N + N), NS + LWDH (N + L), D-gal + NS (D + N) and D-gal + LWDH (D + L) groups. Rats in D + N and D + L groups received daily injection of D-gal (100 mg/kg, s.c.) for six weeks to establish the aging model, while rats in N + N and N + L groups were injected with the same volume of NS. From the third week, rats in N + L and D + L groups were orally administered with a decoction of LWDH for subsequent six weeks. Rats in N + N and D + N groups were orally administered just with the same volume of NS simultaneously. Morris water maze test was employed to evaluate the ability of learning and memory of the rats in all the groups. Acetylcholine (ACh) content, activities of choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) in visual cortex were assayed. Hematoxylin and eosin (HE) staining were used to observe the morphologic injury in hippocampus and visual cortex, and immunohistochemistry was performed to evaluate ChAT and AChE expression levels in the visual cortex. The results showed that the rats in D + N groups exhibited a longer escape latency to platform, lower swimming speed, less percent of target quadrant search time and platform crossings, compared with N + N groups, suggesting the establishment of aging model, while LWDH improved these indexes in D-gal-treated rats. Compared with D + N groups, LWDH increased ACh content and ChAT activity, and decreased AChE activity in visual cortex. Remarkable loss of neurons was found in hippocampus and visual cortex of aging rats, and the injury was significantly attenuated by LWDH. Immunohistochemistry showed D-gal-induced decreases of ChAT and AChE expressions were restored by LWDH. Furthermore, under the neural protection of LWDH, the improvement on platform crossings in male aging rats was better than that in female ones, while in ChAT expression and neuron density in visual cortex, female aging rats obtained more amelioration. These results suggest LWDH can markedly reverse the D-gal-induced cognitive impairments and neuronal damage in both hippocampus and visual cortex, which are achieved at least partly through restoring cholinergic system in central nervous system. Moreover, there is some sex difference in protective effects of LWDH against D-gal-induced impairment.
Animals
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Brain
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metabolism
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pathology
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Cholinergic Fibers
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drug effects
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pathology
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Cognition Disorders
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prevention & control
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Drugs, Chinese Herbal
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pharmacology
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Female
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Galactose
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toxicity
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Hippocampus
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metabolism
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pathology
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Male
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Neurons
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pathology
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Neuroprotective Agents
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pharmacology
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Random Allocation
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Rats
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Rats, Sprague-Dawley
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Visual Cortex
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metabolism
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pathology
3.Residual neurovascular function and retinotopy in a case of hemianopia.
Yi-Ching HO ; Amandine CHEZE ; Yih-Yian SITOH ; Esben Thade PETERSEN ; Kong-Yong GOH ; Albert GJEDDE ; Xavier GOLAY
Annals of the Academy of Medicine, Singapore 2009;38(9):827-831
INTRODUCTIONFor occipital cortex strokes resulting in vision disorders, questions about the viability of residual visual cortex remain.
CLINICAL PICTUREIn a patient with a one-year-old, left, complete, homonymous hemianopia due to a right, posterior cerebral artery, ischaemic infarct, we assessed the visual cortex with fMRI retinotopic mapping prior to starting vision restoration therapy.
OUTCOMEThe patient was found to have residual neurovascular function and retinotopic representation in the surviving visual cortex around the infarcted area.
CONCLUSIONThe ability to respond to stimuli in part of the blind field, though not consciously perceived, suggests the potential for recovery.
Hemianopsia ; diagnosis ; etiology ; physiopathology ; Humans ; Image Processing, Computer-Assisted ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Neural Conduction ; physiology ; Stroke ; complications ; physiopathology ; Visual Cortex ; pathology
4.Effects of alcohol exposure during pregnancy on dendritic spine and synapse of visual cortex in filial mice.
Zhan-jun CUI ; Kai-bing ZHAO ; Shu-guang WEN ; Jun-shi ZHANG ; Dong-ming YU ; Jin-bo DENG
Acta Pharmaceutica Sinica 2010;45(7):833-839
The prenatal ethanol exposure induced the alterations of dendritic spine and synapse in visual cortex and their long-term effect would be investigated in mice from P0 to P30. Pregnant mice were intubated ethanol daily from E5 through the pup's birth to establish mode of prenatal alcohol abuse. The dendritic spines of pyramidal cells in visual cortex of pups were labeled with DiI diolistic assay, and the synaptic ultrastructure was observed under transmission electron microscope. Prenatal alcohol exposure was associated with a significant decrease in the number of dendritic spines of pyramidal neurons in the visual cortex and an increase in their mean length; ultrastructural changes were also observed, with decreased numbers of synaptic vesicles, narrowing of the synaptic cleft and thickening of the postsynaptic density compared to controls. Prenatal alcohol exposure is associated with long-term changes in dendritic spines and synaptic ultrastructure. The changes were dose-dependent with long term effect even at postnatal 30.
Animals
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Dendritic Spines
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ultrastructure
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Ethanol
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toxicity
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Female
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Fetal Alcohol Spectrum Disorders
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etiology
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pathology
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Male
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Mice
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Mice, Inbred C57BL
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Microscopy, Confocal
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Microscopy, Electron, Transmission
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Pregnancy
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Prenatal Exposure Delayed Effects
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pathology
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Pyramidal Cells
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ultrastructure
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Synapses
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ultrastructure
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Visual Cortex
;
ultrastructure
5.Advances in the management of diabetic macular oedema based on evidence from the Diabetic Retinopathy Clinical Research Network.
Lik Thai LIM ; Seen Nee CHIA ; Elliott Yann AH-KEE ; Nejia CHEW ; Manish GUPTA
Singapore medical journal 2015;56(5):237-247
The Diabetic Retinopathy Clinical Research Network (DRCR.net) performs studies on new treatments for diabetic retinopathy. This review aims to summarise recent findings from DRCR.net studies on the treatment of diabetic macular oedema. We performed a PubMed search of articles from the DRCR.net, which included all studies pertaining to the treatment of diabetic maculopathy. The main outcome measures were retinal thickening as assessed by central subfield thickness on optical coherence tomography and improvement of visual acuity on the Early Treatment Diabetic Retinopathy Study (ETDRS) chart. Findings from each study were divided into modalities of treatment, namely photocoagulation, bevacizumab, triamcinolone, ranibizumab and vitrectomy. While modified ETDRS focal/grid laser remains the standard of care, intravitreal corticosteroids or anti-vascular endothelial growth factor agents have also proven to be effective, although they come with associated side effects. The choice of treatment modality for diabetic macular oedema is a clinical judgement call, and depends on the patient's clinical history and assessment.
Adrenal Cortex Hormones
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therapeutic use
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Bevacizumab
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therapeutic use
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Biomedical Research
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organization & administration
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Diabetic Retinopathy
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therapy
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Disease Management
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Disease Progression
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Humans
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Light Coagulation
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Macular Edema
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therapy
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Ranibizumab
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therapeutic use
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Retina
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pathology
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Tomography, Optical Coherence
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Triamcinolone
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therapeutic use
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Vascular Endothelial Growth Factor A
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antagonists & inhibitors
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Visual Acuity
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Vitrectomy
6.Dendritic Cell Factor 1-Knockout Results in Visual Deficit Through the GABA System in Mouse Primary Visual Cortex.
Jieyun SHI ; Qian LI ; Tieqiao WEN
Neuroscience Bulletin 2018;34(3):465-475
The visual system plays an important role in our daily life. In this study, we found that loss of dendritic cell factor 1 (DCF1) in the primary visual cortex (V1) caused a sight deficit in mice and induced an abnormal increase in glutamic acid decarboxylase 67, an enzyme that catalyzes the decarboxylation of glutamate to gamma aminobutyric acid and CO, particularly in layer 5. In vivo electrophysiological recordings confirmed a decrease in delta, theta, and beta oscillation power in DCF1-knockout mice. This study presents a previously unknown function of DCF1 in V1, suggests an unknown contact between DCF1 and GABA systems, and provides insight into the mechanism and treatment of visual deficits.
Animals
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Brain Waves
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genetics
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Disease Models, Animal
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Electroencephalography
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Gene Expression Regulation
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drug effects
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genetics
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Geniculate Bodies
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drug effects
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metabolism
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Ginkgolides
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therapeutic use
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Glutamate Decarboxylase
;
metabolism
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Lactones
;
therapeutic use
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Membrane Proteins
;
deficiency
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genetics
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Mice
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Mice, Inbred C57BL
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Mice, Knockout
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Nerve Tissue Proteins
;
deficiency
;
genetics
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Photic Stimulation
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Proto-Oncogene Proteins c-fos
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metabolism
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Vision Disorders
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drug therapy
;
genetics
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pathology
;
physiopathology
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Visual Cortex
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metabolism
;
pathology
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gamma-Aminobutyric Acid
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metabolism