No abstract available.
Animal ; Chloride Channels/metabolism ; Chloride Channels/biosynthesis* ; Choroid Plexus/metabolism* ; Choroid Plexus/cytology ; Epithelial Cells/metabolism*

OBJECTIVETo explore the effects of acrylamide on the permeability of blood cerebrospinal fluid barrier (BCB) and tight junction protein ZO-1 of choroid plexus in rats and to provide a theoretical basis for explaining the mechanism of nerve injury induced by acrylamide.

METHODSThirty two male Sprague-Dawley rats were randomly divided into ACR and control groups. ACR group was exposed to 20 mg/kg ACR daily for 5 days a week by intraperitoneal injection (i.p.) for 4 weeks. Control group was exposed to normal saline. The neurobehavioral tests (including sensatory and motor functions) were performed every week. At the end of exposure, Evan blue (EB) and Sodium fluorescein (NaFI) content in rat CSF were detected for determining the BCB permeability, Real-time PCR was used to measure the expression levels of ZO-1 mRNA in the epithelium cells of choroid plexus, and laser scanning confocal microscope (LSCM) was utilized to observe the distribution of ZO-1 protein.

RESULTSNeurobehavioral tests showed that the tail-flick latencies of ACR group were 27.77% and 53.71% as long as control group in the 3rd week and 4th week, respectively (P < 0.05). The hind lamb splay distances of ACR group were 131.76% and 153.77% as long as control group in the 3rd week and 4th week, respectively (P < 0.05). Evan blue (EB) and Sodium fluorescein (NaFI) content of ACR group were significantly higher than those of control group (P < 0.05). In the 4th week, the expression level of ZO-1 mRNA in ACR group was 0.21 +/- 0.07, which was significantly lower than that (0.31 +/- 0.11) in control group (P < 0.05). In the 4th week, the ZO-1 protein expression level of choroid plexus in ACR group was significantly lower than that in control group (P < 0.05).

CONCLUSIONAcrylamide could increased the BCB permeability of rats, which may be involved in the central nervous injury induced by ACR.

Acrylamide ; toxicity ; Animals ; Blood-Brain Barrier ; drug effects ; Choroid Plexus ; metabolism ; Male ; Permeability ; drug effects ; Rats ; Rats, Sprague-Dawley ; Zonula Occludens-1 Protein ; metabolism

Accumulating evidence has revealed that brain iron concentrations increase with aging, and the choroid plexus (CP) may be at the basis of iron-mediated toxicity and the increase in inflammation and oxidative stress that occurs with aging. The mechanism involves not only hepcidin, the key hormone in iron metabolism, but also iron-related proteins and signaling-transduction molecules, such as IL-6 and signal transducer and activator of transcription 3 (Stat3). The aim of the present study was to investigate the correlation between the IL-6/Stat3 signaling pathway and hepcidin at the CP in normal aging. Quantitative real time PCR and Western blot were used to determine the alterations in specific mRNA and corresponding protein changes at the CP at ages of 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33 and 36 months in Brown-Norway/Fischer (B-N/F) rats. The results demonstrated that hepcidin mRNA level at the CP kept stable in young rats (from 3 to 18 months), and increased with aging (from 21 to 36 months). The alterations of IL-6/p-Stat3 mRNA and protein expressions in normal aging were in accordance with that of hepcidin mRNA. Our data suggest that IL-6 may regulate hepcidin expression at the CP, upon interaction with the cognate cellular receptor, and through the Stat3 signaling transduction pathway.
Aging ; physiology ; Animals ; Choroid Plexus ; metabolism ; Hepcidins ; physiology ; Interleukin-6 ; physiology ; Iron ; metabolism ; RNA, Messenger ; Rats ; Rats, Inbred F344 ; STAT3 Transcription Factor ; physiology ; Signal Transduction

OBJECTIVETo investigate the effects of lead exposure on the copper concentration in the brain and serum and the expression of copper transporters in the choroid plexus among rats.

METHODSSixty specific pathogen-free Sprague-Dawley rats were randomly divided into a control group and three lead-exposed groups, with 8 mice in each group. The lead-exposed groups were orally administrated with 500 (low-dose group)), 1 000 (middle-dose group), and 2 000 mg/L (high-dose group) lead acetate in drinking water for eight weeks. And the rats in control group were given 2 000 mg/L sodium acetate in drinking water. The content of lead and copper in the serum, hippocampus, cortex, choroid plexus, bones, and cerebrospinal fluid (CSF) was determined by inductively coupled plasma-mass spectrometry (ICP-MS). Confocal and real-time PCR methods were applied to measure the expression of copper transporters including copper transporter 1 (Ctr1), antioxidant protein 1 (ATX1), and Cu ATPase (ATP7A).

RESULTSCompared with the control group, the lead-exposed groups showed significantly higher lead concentrations in the serum, cortex, hippocampus, choroid plexus, CSF, and bones (P < 0.05) and significantly higher copper concentrations in the CSF, choroid plexus, serum, and hippocampus (P < 0.05). Confocal images showed that Ctr1 protein was expressed in the cytoplasm and cell membrane of choroid plexus in control group. However, Ctr1 migrated to CSF surface microvilli after lead exposure. Ctr1 fluorescence intensity gradually increased with increasing dose of lead, except that the middle-dose group had a higher Ctr1 fluorescence intensity than the high-dose group. In addition, the middle- and high-dose groups showed a lower ATX1 fluorescence intensity compared with the control group. Real-time PCR data indicated that the three lead-exposed groups showed significantly higher mRNA levels of Ctr1 and ATP7A compared with the control group (P < 0.05).

CONCLUSIONCopper homeostasis in the choroid plexus is affected by lead exposure to induce copper homeostasis disorders in brain tissue, which may be one of the mechanisms of lead neurotoxicity.

Adenosine Triphosphatases ; Animals ; Brain ; Cation Transport Proteins ; drug effects ; Choroid Plexus ; drug effects ; metabolism ; Copper ; metabolism ; Homeostasis ; Organometallic Compounds ; toxicity ; RNA, Messenger ; Rats ; Rats, Sprague-Dawley

Objective: To investigate the effect of nuclear factor erythroid 2-related factor 2 (Nrf2) in the alteration of tight junction protein expression in choroid plexus epithelial cells created by lanthanum-activated matrix metalloproteinase 9 (MMP9) . Methods: In October 2020, immortalized rat choroid plexus epithelial cell line (Z310) cells were used as the blood-cerebrospinal fluid barrier in vitro, and were divided into control group and 0.125, 0.25, 0.5 mmol/L lanthanum chloride (LaCl(3)) treatment group. After treating Z310 cells with different concentrations of LaCl(3) for 24 hours, the morphological changes of Z310 cells were observed under inverted microscope, the protein expression levels of MMP9, occludin and zonula occludens-1 (ZO-1) were observed by cellular immunofluorescence method, and the protein expression levels of MMP9, tissue inhibitors of metalloproteinase1 (TIMP1) , occludin, ZO-1 and Nrf2 were detected by Western blotting. The level of reactive oxygen species (ROS) in cells was detected by flow cytometry. Results: Compared with the control group, Z310 cells in the LaCl(3) treatment group were smaller in size, with fewer intercellular junctions, and more dead cells and cell fragments. The expression level of MMP9 protein in cells treated with 0.25 and 0.5 mmol/L LaCl(3) was significantly higher than that in the control group (P<0.05) , and the expression level of TIMP1 and tight junction proteins occudin and ZO-1 was significantly lower than that in the control group (P<0.05) . Compared with the control group, the ROS production level in the 0.25, 0.5 mmol/L LaCl(3) treatment group was significantly increased (P<0.05) , and the Nrf2 protein expression level in the 0.125, 0.25, 0.5 mmol/L LaCl(3) treatment group was significantly decreased (P<0.05) . Conclusion: Lanthanum may increase the level of ROS in cells by down regulating the expression of Nrf2, thus activating MMP9 to reduce the expression level of intercellular tight junction proteins occludin and ZO-1.
Rats ; Animals ; Matrix Metalloproteinase 9/metabolism* ; NF-E2-Related Factor 2/metabolism* ; Tight Junction Proteins/metabolism* ; Occludin/pharmacology* ; Choroid Plexus/metabolism* ; Reactive Oxygen Species/metabolism* ; Lanthanum/pharmacology* ; Epithelial Cells ; Zonula Occludens-1 Protein/metabolism* ; Phosphoproteins/pharmacology*

OBJECTIVETo investigate the diagnostic significance of D2-40 and annexin-1 in the ependymal tumors.

METHODSTo analyses the expression of D2-40, annexin-1, EMA and Ki-67 by immunohistochemistry in 52 cases of ependymal tumors (48 cases of ependymomas, 4 cases of choroid plexus papilloma) from Xuanwu Hospital from 2005 to 2009. Ten cases of corresponding normal brain tissue were also obtained as control.

RESULTSThirty-two of forty-eight (66.7%) cases of ependymomas were positive for D2-40. "Dot-like" and "ring-like" structures were commonly observed in ependymomas (55.3%, 21 of 38 cases) and anaplastic ependymomas (5 of 6 cases) with D2-40 staining. There was no difference in the expression between D2-40 and Ki-67 (r(s) = -0.013, P = 0.931). For annexin-1, 87.5% (42 of 48 cases) of the ependymomas were positive. The specific "granular structures" and cilium were observed in ependymomas (1 of 4 cases of myxopapillary ependymomas and 11 of 38 cases of ependymomas respectively) for annexin-1. The difference in expression between annexin-1 and Ki-67 was statistically significant (r(s) = -0.405, P = 0.005). D2-40 in combination of EMA and annexin-1 increased the positive rate to 100% in ependymomas. Choroid plexus papillomas were all positive for D2-40 and annexin-1. The control tissue was negative for D2-40 but positive for annexin-1 in the capillaries.

CONCLUSIONSThe specific structures are valuable in diagnosing of ependymal-genetic tumors, and are highlighted by D2-40 and annexin-1. D2-40 in combination of EMA and annexin-1 is a useful diagnostic marker for ependymal tumors.

Adolescent ; Adult ; Annexin A1 ; metabolism ; Biomarkers, Tumor ; metabolism ; Brain Neoplasms ; diagnosis ; metabolism ; pathology ; Child ; Child, Preschool ; Ependymoma ; diagnosis ; metabolism ; pathology ; Female ; Humans ; Immunohistochemistry ; Ki-67 Antigen ; metabolism ; Male ; Membrane Glycoproteins ; metabolism ; Middle Aged ; Mucin-1 ; metabolism ; Papilloma, Choroid Plexus ; diagnosis ; metabolism ; pathology ; Young Adult

OBJECTIVETo study the clinicopathologic features and immunophenotype of endolymphatic sac tumor (ELST) and normal endolymphatic sac.

METHODSThe clinical and histologic features were evaluated in 5 cases of ELST. Eight cases of choroid plexus papilloma at cerebellopontine angle and 2 cases of normal endolymphatic sac were used as controls. Immunohistochemical study for vimentin, AE1/AE3, CK8/18, CK5/6, EMA, GFAP, synaptophysin, S-100 protein, CEA, TTF-1, VEGF, D2-40, calponin, calretinin and Ki-67 was carried out.

RESULTSThe age of onset of ELST ranged from 23 to 35 years (median = 24 years). The male-to-female ratio was 2:3. The clinical presentation was tinnitus, otalgia, hearing loss, otorrhagia with effusion and headache. The duration of symptoms ranged from 6 months to 10 years. Local recurrences were noted in 3 cases. Radiologically, the tumors were located at cerebellopontine angle and demonstrated petrous bone destruction. Histologic examination showed that the tumors had a papillary-glandular pattern. The papillae were covered by a single layer of low cuboidal cells. The tumor cells had distinct cell borders and contained eosinophilic to clear cytoplasm. The nuclei were slightly atypical and sometimes apically located. Focal dilated glandular structures with colloid-like material were also identified. The surrounding stroma was vascularized. All of the 5 cases had dural or petrous bone infiltration. Immunohistochemical study showed that all of the 5 cases were positive for AE1/AE3, CK8/18, CK5/6 and VEGF, 4 cases for EMA, 3 cases for calponin (focal), 2 cases for vimentin, 2 cases for S-100 protein, 1 case for GFAP and 1 case for synaptophysin (focal and weak). The Ki-67 index measured less than 1%. The staining for D2-40, calretinin, CEA and TTF-1 was negative. The 2 cases of the normal endolymphatic sac were positive for AE1/AE3 and CK8/18, and negative for CK5/6, EMA, S-100 protein, GFAP and synaptophysin. The 8 cases of choroid plexus papilloma were positive for synaptophysin. Seven cases were also positive for S-100 protein, 2 cases for GFAP and 1 case for D2-40. All of the 8 cases were negative for EMA, CK5/6 and calponin.

CONCLUSIONSELST is a rare slow-growing and potentially malignant tumor with a tendency of bone invasion and local recurrence. Distant metastasis is not observed. It must be distinguished from choroid plexus papilloma occurring at cerebellopontine angle. Correlation with clinical, radiologic and immunohistochemical findings would also be helpful.

Adenocarcinoma ; diagnostic imaging ; metabolism ; pathology ; surgery ; Adult ; Calcium-Binding Proteins ; metabolism ; Cerebellar Neoplasms ; diagnostic imaging ; metabolism ; pathology ; surgery ; Cerebellopontine Angle ; pathology ; Diagnosis, Differential ; Endolymphatic Sac ; pathology ; Female ; Follow-Up Studies ; Humans ; Immunohistochemistry ; Keratin-5 ; metabolism ; Keratin-6 ; metabolism ; Male ; Microfilament Proteins ; metabolism ; Mucin-1 ; metabolism ; Neoplasm Recurrence, Local ; Papilloma, Choroid Plexus ; metabolism ; pathology ; Tomography, X-Ray Computed ; Young Adult

Accumulation of amyloid-beta peptides (Aβ) results in amyloid burden in normal aging brain. Clearance of this peptide from the brain occurs via active transport at the interfaces separating the central nervous system (CNS) from the peripheral circulation. The present study was to investigate the change of Aβ transporters expression at the choroid plexus (CP) in normal aging. Morphological modifications of CP were observed by transmission electron microscope. Real-time RT-PCR was used to measure mRNA expressions of Aβ(42) and its transporters, which include low density lipoprotein receptor-related protein-1 and 2 (LRP-1 and -2), P-glycoprotein (P-gp) and the receptor for advanced glycation end-products (RAGE), at the CP epithelium in rats at ages of 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33 and 36 months. At the same time, the mRNA expressions of oxidative stress-related proteins were also measured. The results showed that a striking deterioration of the CP epithelial cells and increased Aβ(42) mRNA expression were observed in aged rats, and there was a decrease in the transcription of the Aβ efflux transporters, LRP-1 and P-gp, no change in RAGE mRNA expression and an increase in LRP-2, the CP epithelium Aβ influx transporter. Heme oxygenase-1 (HO-1) and caspase-3 expressions at the CP epithelium increased with age at the mRNA level. These results suggest the efficacy of the CP in clearing of Aβ deceases in normal aging, which results in the increase of brain Aβ accumulation. And excess Aβ interferes with oxidative phosphorylation, leads to oxidative stress and morphological structural changes. This in turn induces further pathological cascades of toxicity, inflammation and neurodegeneration process.
ATP Binding Cassette Transporter, Sub-Family B ; metabolism ; Aging ; Amyloid beta-Peptides ; metabolism ; Animals ; Caspase 3 ; metabolism ; Choroid Plexus ; physiology ; Heme Oxygenase (Decyclizing) ; metabolism ; LDL-Receptor Related Proteins ; metabolism ; Oxidative Stress ; Peptide Fragments ; metabolism ; Rats ; Receptor for Advanced Glycation End Products ; Receptors, Immunologic ; metabolism