The blood-brain barrier (BBB) plays important roles in both the physiological and pharmacological state of the brain. Transiently enhancing the permeability of the BBB may allow use of more types of medications for neuropsychiatric diseases. Several studies have demonstrated that seizures cause a transient decrease in BBB integrity.
View Article and Find Full Text PDFClinical phenotypes of hereditary diffuse leukoencephalopathy with spheroids (HDLS), a familial progressive neurodegenerative disorder affecting the white matter of the brain, are heterogenous and may include behavioral and personality changes, memory impairment, parkinsonism, seizure, and spasticity. Thus, HDLS is frequently unrecognized and misdiagnosed. Heterozygous mutations located within the kinase domain of the gene encoding the colony-stimulating factor 1 receptor (CSF1R), a cell surface receptor with key roles in development and innate immunity, have been shown in HDLS.
View Article and Find Full Text PDFIn our previous studies, we reported that the activity of an anti-oxidant enzyme, Cu,Zn-superoxide dismutase (Cu,Zn-SOD) became decreased as the result of glycation in vitro and in vivo. Glycated Cu,Zn-SOD produces hydroxyl radicals in the presence of transition metals due to the formation of a Schiff base adduct and a subsequent Amadori product. This results in the site-specific cleavage of the molecule, followed by random fragmentation.
View Article and Find Full Text PDFLysosome-associated membrane protein-2 (LAMP-2) is the gene responsible for Danon disease, which is characterized by cardiomyopathy, autophagic vacuolar myopathy, and variable mental retardation. To elucidate the function of LAMP-2 in the central nervous system, we investigated the neuropathological changes in Lamp-2-deficient mice. Immunohistochemical observations revealed that Lamp-1 and cathepsin D-positive lysosomal structures increased in the large neurons of the mouse brain.
View Article and Find Full Text PDFImpaired clearance of soluble Aβ (amyloid-β) promotes Aβ aggregation in brains with Alzheimer's disease (AD), while apolipoprotein-E (ApoE) in microglia mediates Aβ clearance. We studied the protease responsible for ApoE(4) degradation in human peripheral monocyte extracts, which are from the same lineage as microglia. We detected the hydrolytic activity for ApoE(4) in high-salt extracts with 2 M NaCl and found that the activity was inhibited by a serine protease inhibitor and an elastase-specific inhibitor, but not by other protease inhibitors.
View Article and Find Full Text PDFLysosomes are the primary catabolic compartment for the degradation of intracellular proteins through autophagy. The presence of abnormal intracellular α-synuclein-positive aggregates in Parkinson's disease (PD) indicates that the degradative capacity of lysosomes is impaired in PD. Specific dysfunction of chaperone-mediated autophagy (CMA) in PD is suggested by reductions in the CMA membrane receptor, lysosomal-associated membrane protein (LAMP) 2A, although whether LAMP2A is the only LAMP2 isoform affected by PD is unknown.
View Article and Find Full Text PDFDanon disease is an X-linked disorder clinically characterized by the triad of hypertrophic cardiomyopathy, myopathy, and intellectual disability. Cardiomyopathy is a severe and life-threatening problem, for which cardiac transplantation is the only therapeutic option. The most striking finding in muscle biopsy samples is small basophilic granules scattered in myofibers, which are in fact small autophagic vacuoles surrounded by membranes with sarcolemmal features characterized by the recruitment of sarcolemmal proteins and acetylcholine esterase and by the presence of basal lamina on its luminal side.
View Article and Find Full Text PDFThe seeding of amyloid-β 40 (Aβ40) oligomers from monomers is the initial step of Aβ aggregation, and many reports have suggested that cholesterol enhances this step. We studied the potential of secosteroid vitamin D derivatives for Aβ40 aggregation in vitro. The quartz-crystal microbalance technique demonstrated that vitamin D3 does not show any effect on Aβ40 aggregation while vitamin D2 promoted it and docking simulation but that vitamin D2 has high potential in this regard.
View Article and Find Full Text PDFRegulated degradation of cellular components by lysosomes is essential to maintain biological homeostasis. In mammals, three forms of autophagy, macroautophagy, microautophagy and chaperone-mediated autophagy (CMA), have been identified. Here, we showed a novel type of autophagy, in which RNA is taken up directly into lysosomes for degradation.
View Article and Find Full Text PDFVasoactive intestinal peptide (VIP) is a pleiotropic neuropeptide that acts as a neuromodulator in the CNS. Recently, secretion of several functional molecules has been identified in VIP-stimulated astrocytes in vitro. However, the relationship between VIP and its specific receptors in neurological disorders remains unknown.
View Article and Find Full Text PDFLipid peroxidation has many deleterious effects on cells, and in the nervous system is considered to be involved in the pathogenesis of neurodegenerative diseases. To suppress lipid peroxidation, cells have various defense systems such as glutathione and thioredoxin, and defects in these defense systems will result in disturbance of normal cellular functions. Here we report that deficiency of ubiquitin carboxy-terminal hydrolase-L1 (UCH-L1) leads to vulnerability to lipid peroxidation both in vivo and in vitro, through analyses of the UCH-L1-deficient mutant mouse gracile axonal dystrophy (gad).
View Article and Find Full Text PDF2-[Bis(pentafluorophenyl)boryl]azobenzenes bearing hydrogen, methoxy, dimethylamino, trifluoromethyl, fluoro, n-butyl, and tert-butyldimethylsiloxy groups at the 4'-position or methoxy and bromo groups at the 4-position have been synthesized. The 4-bromo group of the 2-boryl-4-bromoazobenzene derivative was converted to phenyl and diphenylamino groups by palladium-catalyzed reactions. The absorption and fluorescence properties have been investigated using UV/Vis and fluorescence spectroscopy.
View Article and Find Full Text PDFParkinson disease (PD) is the most common neurodegenerative movement disorder. An increase in the amount of alpha-synuclein protein could constitute a cause of PD. Alpha-synuclein is degraded at least partly by chaperone-mediated autophagy (CMA).
View Article and Find Full Text PDFG-protein coupled receptors (GPCRs) form the largest superfamily of membrane proteins. About 50% of medicines are thought to target GPCRs. We recently developed a novel strategy to screen GPCRs that are highly or selectively expressed in particular cells of the brain.
View Article and Find Full Text PDFThe Pituitary adenylate cyclase-activating peptide (PACAP) ligand/type 1 receptor (PAC1) system regulates neurogenesis and gliogenesis. It has been well established that the PACAP/PAC1 system induces differentiation of neural progenitor cells (NPCs) through the Gs-mediated cAMP-dependent signaling pathway. However, it is unknown whether this ligand/receptor system has a function in proliferation of NPCs.
View Article and Find Full Text PDFThe I93M mutation in ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) was reported in one German family with autosomal dominant Parkinson's disease (PD). The causative role of the mutation has, however, been questioned. We generated transgenic (Tg) mice carrying human UCHL1 under control of the PDGF-B promoter; two independent lines were generated with the I93M mutation (a high- and low-expressing line) and one line with wild-type human UCH-L1.
View Article and Find Full Text PDFUCH-L3 belongs to the ubiquitin C-terminal hydrolase family that deubiquitinates ubiquitin-protein conjugates in the ubiquitin-proteasome system. A murine Uchl3 deletion mutant displays retinal degeneration, muscular degeneration, and mild growth retardation. To elucidate the function of UCH-L3, we investigated histopathological changes and expression of apoptosis- and oxidative stress-related proteins during retinal degeneration.
View Article and Find Full Text PDFRoot-rupture injury is a type of preganglionic brachial plexus injury resulting from traction force, where a small section of the spinal root is usually left behind. We have established experimental models of both root-rupture injury with traction force and rhizotomy without traction force in rats and we examined the activation of microglia/ macrophages in both conditions. LGP107 and LGP96, which are rat homologs of lysosome-associated membrane proteins, were most useful as immunohistochemical markers of mononuclear phagocytes.
View Article and Find Full Text PDFGlutamate transporters are thought to have an important role in central nervous system (CNS) development. We investigated the expression of the sodium-dependent high-affinity glutamate transporters EAAT1, EAAT2, and EAAT3 in 11 human autopsied cases without neurological disorders and in four cases with type II lissencephaly including Walker Warburg's syndrome (WWS) and Fukuyama-type congenital muscular dystrophy (FCMD), both of which are classified as migration disorders of the human brain. Expression of glutamate transporter subtypes was differentially regulated during normal human corticogenesis.
View Article and Find Full Text PDFThe synuclein family includes three isoforms, termed alpha, beta and gamma. alpha-Synuclein accumulates in various pathological lesions resulting from neurodegenerative disorders including Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy. However, neither beta- nor gamma-synuclein has been detected in Lewy bodies, and thus it is unclear whether these isoforms contribute to neurological pathology.
View Article and Find Full Text PDFAstrocytosis is a sequential morphological change of astrocytic reaction to tissue damage, and is associated with regulation of antioxidant defense mechanisms to reduce oxidative damage. The repair enzymes to oxidative DNA damage, oxidized purine-nucleoside triphosphatase (hMTH1) and a mitochondrial type of 8-oxoguanine DNA glycosylase (hOGG1-2a) in brain tumors and neurons of Alzheimer's disease, were previously reported. In the present study, glial expression of these repair enzymes under such pathological conditions as cerebrovascular diseases and metastatic brain tumors, were investigated.
View Article and Find Full Text PDFN-myc downregulated gene 1 (NDRG1) is a 43-kD protein whose mRNA is induced by DNA damage, hypoxia, or prolonged elevation of intracellular calcium. Although NDRG1 is also upregulated during cell differentiation, there are few studies on NDRG1 expression during postnatal development. Here we investigated the expression and cellular distribution of NDRG1 protein in rat kidney and brain during postnatal development.
View Article and Find Full Text PDFIn dementia with Lewy bodies (DLB), the Lewy bodies (LBs) are an essential substrate. Although LB pathology has gained increasing attention as one of the major causes of dementia, little is known about the exact prevalence of LB pathology in the general population. In addition, the pathology of Alzheimer-type dementia (ATD) is frequently associated with DLB.
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