Objective: To investigate the expression of cation chloride cotransporter (NKCC1/KCC2) in the neurons from cerebral lesions of children with focal cortical dysplasia (FCD) type Ⅱ, to provide a morphological basis for revealing the possible mechanism of epilepsy. Methods: Eight cases of FCD type Ⅱ diagnosed at Beijing Haidian Hospital, Beijing, China and 12 cases diagnosed at Xuanwu Hospital, Capital Medical University, Beijing, China from February 2017 to December 2019 were included. The expression of NKCC1 and KCC2 in FCD type Ⅱa and FCD type Ⅱb was detected using immunohistochemistry and double immunohistochemical stains. The average optical density of NKCC1 in dysmorphic neurons and normal neurons was also determined using immunohistochemical staining in FCD type Ⅱa (10 cases). Results: The patients were all younger than 14 years of age. Ten cases were classified as FCD type IIa, and 10 cases as FCD type Ⅱb. NKCC1 was expressed in the cytoplasm of normal cerebral cortex neurons and KCC2 expressed on cell membranes. In dysmorphic neurons of FCD type Ⅱa, expression of NKCC1 increased, which was statistically higher than that of normal neurons (P<0.01). Aberrant expression of KCC2 in dysmorphic neurons was also noted in the cytoplasm. In the FCD Ⅱb type, the expression pattern of NKCC1/KCC2 in dysmorphic neurons was the same as that of FCD type Ⅱa. The aberrant expression of NKCC1 in balloon cells was negative or weakly positive on the cell membrane, while the aberrant expression of KCC2 was absent. Conclusions: The expression pattern of NKCC1/KCC2 in dysmorphic neurons and balloon cells is completely different from that of normal neurons. The NKCC1/KCC2 protein-expression changes may affect the transmembrane chloride flow of neurons, modify the effect of inhibitory neurotransmitters γ-aminobutyric acid and increase neuronal excitability. These effects may be related to the occurrence of clinical epileptic symptoms.
Child ; Humans ; Brain/pathology* ; Cations/metabolism* ; Chlorides/metabolism* ; Epilepsy/metabolism* ; Malformations of Cortical Development, Group I/metabolism* ; Solute Carrier Family 12, Member 2/metabolism* ; Symporters/metabolism*

Radioiodine ablation (RIA) therapy is one of the most important treatments for papillary thyroid carcinoma (PTC), but some patients who received (131)I have radioiodine-refractory disease caused by the decreased expression of the Na(+)/I(-) symporter (NIS). BRAF(V600E) mutation is one possible risk factor that can disturb the NIS expression, but the roles are unclear in clinical practice. This research discussed the association of BRAF(V600E) mutation and NIS expression in PTC tissue and the clinical implications in RIA therapy. 134 PTC samples were collected between June 2013 and June 2014 from Tongji Hospital affiliated to Tongji Medical College, and their clinical characteristics were analyzed. RT-PCR was used to detect the BRAF(V600E) mutation from formalin-fixed paraffin-embedded samples, and immunohistochemistry was applied to detect the NIS expression. IPP software was used to calculate the relative expression quantity of NIS. We found that there was no significant correlation between the absorbance (A) values of NIS and clinicopathologic features in these cases, even thyroid stimulating hormone. BRAF(V600E) mutation showed inhibitory effect on the NIS expression without statistically significant difference in all PTC cases (β=-0.0195, P=0.085), but in the subgroup without hashimoto's thyroiditis (HT), BRAF(V600E) mutation could significantly inhibit the NIS expression (β=-0.0257, P=0.046). The results indicate that BRAF(V600E) mutation is correlated with a lower expression of NIS in PTCs without HT, suggesting the radioiodine-refractory effects during RIA therapy in these patients.
Adult ; Carcinoma ; genetics ; metabolism ; Carcinoma, Papillary ; Case-Control Studies ; Female ; Humans ; Male ; Middle Aged ; Mutation, Missense ; Proto-Oncogene Proteins B-raf ; genetics ; Symporters ; genetics ; metabolism ; Thyroid Neoplasms ; genetics ; metabolism

NTCP is specifically expressed on the basolateral membrane of hepatocytes, participating in the enterohepatic circulation of bile salts, especially conjugated bile salts, to maintain bile salts homeostasis. In addition, recent studies have found that NTCP is a functional receptor of HBV and HDV. Therefore, it is important to study the interaction between drugs and NTCP and identify the inhibitors/substrates of NTCP. In the present study, a LLC-PK1 cell model stably expressing human NTCP was established, which was simple and suitable for high throughput screening, and utilized to screen and verify the potential inhibitors of NTCP from 102 herbal medicinal ingredients. The results showed that ginkgolic acid (GA) (13 : 0), GA (15 : 1), GA (17 : 1), erythrosine B, silibinin, and emodin have inhibitory effects on NTCP uptake of TCNa in a concentration-dependent manner. Among them, GA (13 : 0) and GA (15 : 1) exhibited the stronger inhibitory effects, with IC50 values being less than 8.3 and 13.5 μmol·L(-1), respectively, than the classical inhibitor, cyclosporin A (CsA) (IC50 = 20.33 μmol·L(-1)). Further research demonstrated that GA (13 : 0), GA (15 : 1), GA (17 : 1), silibinin, and emodin were not substrates of NTCP. These findings might contribute to a better understanding of the disposition of the herbal ingredients in vivo, especially in biliary excretion.
Animals ; Drug Evaluation, Preclinical ; Humans ; Kinetics ; LLC-PK1 Cells ; Models, Biological ; Organic Anion Transporters, Sodium-Dependent ; antagonists & inhibitors ; chemistry ; metabolism ; Plant Extracts ; chemistry ; pharmacology ; Plants, Medicinal ; chemistry ; Structure-Activity Relationship ; Swine ; Symporters ; antagonists & inhibitors ; chemistry ; metabolism

Hepatitis B virus (HBV) is the prototype of hepatotropic DNA viruses (hepadnaviruses) infecting a wide range of human and non-human hosts. Previous studies with duck hepatitis B virus (DHBV) identified duck carboxypeptidase D (dCPD) as a host specific binding partner for full-length large envelope protein, and p120 as a binding partner for several truncated versions of the large envelope protein. p120 is the P protein of duck glycine decarboxylase (dGLDC) with restricted expression in DHBV infectible tissues. Several lines of evidence suggest the importance of dCPD, and especially p120, in productive DHBV infection, although neither dCPD nor p120 cDNA could confer susceptibility to DHBV infection in any cell line. Recently, sodium taurocholate cotransporting polypeptide (NTCP) has been identified as a binding partner for the N-terminus of HBV large envelope protein. Importantly, knock down and reconstitution experiments unequivocally demonstrated that NTCP is both necessary and sufficient for in vitro infection by HBV and hepatitis delta virus (HDV), an RNA virus using HBV envelope proteins for its transmission. What remains unclear is whether NTCP is the major HBV receptor in vivo. The fact that some HBV patients are homozygous with an NTCP mutation known to abolish its receptor function suggests the existence of NTCP-independent pathways of HBV entry. Also, NTCP very likely mediates just one step of the HBV entry process, with additional co-factors for productive HBV infection still to be discovered. NTCP offers a novel therapeutic target for the control of chronic HBV infection.
Animals ; Carboxypeptidases/genetics/*metabolism ; Gene Products, pol/genetics/metabolism ; Heparan Sulfate Proteoglycans/metabolism ; Hepatitis B virus/*physiology ; Hepatocytes/metabolism/virology ; Organic Anion Transporters, Sodium-Dependent/antagonists & inhibitors/genetics/metabolism ; RNA Interference ; Symporters/antagonists & inhibitors/genetics/metabolism ; Viral Envelope Proteins/metabolism ; Virus Internalization

No abstract available.
Fluorodeoxyglucose F18/diagnostic use ; Genetic Variation ; Humans ; Individualized Medicine/*methods ; Iodine Radioisotopes/*therapeutic use ; Molecular Imaging/methods ; Positron-Emission Tomography ; Symporters/biosynthesis/*metabolism ; Thyroid Neoplasms/*drug therapy/*genetics ; Tumor Microenvironment

B-RafV600E mutant is found in 40-70% of papillary thyroid carcinoma (PTC) and has an important role in the pathogenesis of PTC. The sodium iodide symporter (NIS) is an integral plasma membrane glycoprotein that mediates active iodide transport into the thyroid follicular cells, and B-RafV600E has been known to be associated with the loss of NIS expression. In this study, we found that B-RafV600E inhibited NIS expression by the upregulation of its promoter methylation, and that specific regions of CpG islands of NIS promoter in B-RafV600E harboring PTC were highly methylated compared with surrounding normal tissue. Although DNA methyltransferase 3a and 3b (DNMT3a,3b) were not increased by B-RafV600E, DNMT1 expression was markedly upregulated in PTC and B-RafV600E expressing thyrocytes. Furthermore, DNMT1 expression was upregulated by B-RafV600E induced NF-kappaB activation. These results led us to conclude that NIS promoter methylation, which was induced by B-RafV600E, is one of the possible mechanisms involved in NIS downregulation in PTC.
Base Sequence ; Carcinoma/*genetics/metabolism/pathology ; Cells, Cultured ; DNA (Cytosine-5-)-Methyltransferase/analysis/*genetics/metabolism ; DNA Methylation ; Down-Regulation ; *Gene Expression Regulation, Neoplastic ; Humans ; Molecular Sequence Data ; *Point Mutation ; Promoter Regions, Genetic ; Proto-Oncogene Proteins B-raf/*genetics/metabolism ; Symporters/analysis/*genetics/metabolism ; Thyroid Gland/cytology/metabolism/pathology ; Thyroid Neoplasms/*genetics/metabolism/pathology ; Up-Regulation

OBJECTIVETo study changes in the expression levels of parvalbumin (PV), glutamate decarboxylase 67 (GAD67) and K+-Cl- cotransporter 2 (KCC2) in the brain tissue of rats with schizophrenia (SZ) induced by dizocilpine (MK-801), and to investigate the mechanism involving gamma-aminobutyric acid (GABA) by which NMDA receptor blocker induces SZ in the perinatal period.

METHODSThirty-six neonatal male Sprague-Dawley rats were randomly assigned to two batches on postnatal day 6. Each batch was divided into normal control (treated by 0.9% normal saline), SZ-development model (treated by subcutaneous injection of 0.1 mg/kg MK-801 on postnatal days 7-10; bid), and SZ-chronic medication model groups (treated by intraperitoneal injection of 0.2 mg/kg MK-801 on postnatal days 47-60; qd). On postnatal day 63, the brain tissue of the first batch of rats was obtained and then fixed with paraform for histological sections; expression levels of PV and GAD67 in the medial prefrontal cortex (mPFC) and hippocampus CA1 were measured by immunohistochemistry. Simultaneously, the second batch of rats was sacrificed and the mPFC and hippocampus were obtained and homogenized; expression levels of KCC2 in the mPFC and hippocampus were measured by Western blot.

RESULTSExpression levels of PV and GAD67 in the mPFC and hippocampus CA1 were significantly lower in the SZ-development and chronic medication model groups than in the normal control group (P<0.05). Expression levels of KCC2 in the mPFC and hippocampus were significantly lower in the SZ-development model group than in the SZ-chronic medication model and normal control groups (P<0.05).

CONCLUSIONSThe expression changes of PV and GAD67 in SZ can be simulated using the SZ development model induced by MK-801, which might affect the development of the GABA system in the PFC and hippocampus by downregulating KCC2 expression.

Animals ; CA1 Region, Hippocampal ; chemistry ; Dizocilpine Maleate ; pharmacology ; Glutamate Decarboxylase ; analysis ; Immunohistochemistry ; Male ; Parvalbumins ; analysis ; Prefrontal Cortex ; chemistry ; Rats ; Rats, Sprague-Dawley ; Schizophrenia ; etiology ; metabolism ; Symporters ; analysis

PURPOSE: To evaluate the expression of the Na(+)-K(+)-2Cl(-)-cotransporter 2 (NKCC2) in the ischemic rat retina. METHODS: Retinal ischemia was induced by pressures 90 to 120 mmHg, above systemic systolic pressure. Immunohistochemistry and western blot analysis were performed. RESULTS: NKCC2 is expressed in the normal retina and its expression is increased by ischemia caused by intraocular pressure elevation. NKCC2 immunoreactivity was observed mainly in axon bundles of ganglion cells and horizontal cell processes in the retina. NKCC2 expression continuously increased with a peak value 3 days (to 415% of normal levels) after ischemic injury, and then gradually decreased to 314% of controls until 2 weeks post injury. The mean density of NKCC2-labeled ganglion cells per mm2 changed from 1,255 +/- 109 in normal retinas to 391 +/- 49 and 185 +/- 37 at 3 days and 2 weeks after ischemia, respectively (p < 0.05), implying cell death of ganglion cells labeled with NKCC2. CONCLUSIONS: Taken together, these results suggest that NKCC2, which is expressed in retinal ganglion and horizontal cells, may contribute to cell death by ischemic injury in the retina, although the molecular mechanisms involved remain to be clarified.
Animals ; Blotting, Western ; Disease Models, Animal ; Immunohistochemistry ; Intraocular Pressure ; Ischemia/etiology/*metabolism ; Male ; Microscopy, Confocal ; Ocular Hypertension/*complications/metabolism/physiopathology ; Rats ; Rats, Sprague-Dawley ; Retinal Diseases/etiology/*metabolism ; Retinal Ganglion Cells/*metabolism/pathology ; Sodium-Potassium-Chloride Symporters/*biosynthesis

Liver is regarded as one of the most important organs for drug clearance in the body, which mediates both the metabolism and biliary excretion of drugs. Transporters are a class of functional membrane proteins and control the movement of substances into or out of cells. Transporters, which are extensively expressed in the liver, play important roles in the drug hepatic disposition by regulating the uptake of drugs from blood into hepatocytes or the efflux of drugs and their metabolites into bile. In this review, the localization, functions and substrate selectivity of the major transporters in the liver will be summarized, and the impacts of these transporters on drug hepatic disposition, the potential drug-drug interactions as well as their genetic polymorphisms will also be reviewed.
ATP Binding Cassette Transporter, Sub-Family G, Member 2 ; ATP-Binding Cassette Transporters ; genetics ; metabolism ; ATP-Binding Cassette, Sub-Family B, Member 1 ; genetics ; metabolism ; Bile ; metabolism ; Biological Transport ; Drug Interactions ; Humans ; Liver ; metabolism ; Membrane Transport Proteins ; genetics ; metabolism ; Metabolic Clearance Rate ; Multidrug Resistance-Associated Proteins ; genetics ; metabolism ; Neoplasm Proteins ; genetics ; metabolism ; Organic Anion Transporters ; genetics ; metabolism ; Organic Anion Transporters, Sodium-Dependent ; metabolism ; Organic Anion Transporters, Sodium-Independent ; genetics ; metabolism ; Organic Cation Transport Proteins ; genetics ; metabolism ; Pharmacokinetics ; Polymorphism, Genetic ; Symporters ; metabolism

The absorption of oral drug in the intestine is an important factor to determine the drug bioavailability. There are many intestinal transporters mediating drug absorption, distribution, excretion and drug-drug interaction. Understanding the transport mechanism can improve the effectiveness and safety of drug and guide clinical rational use of drugs. The in vivo and in vitro methods are used to predict the transport mechanism of drugs by intestinal transporters in the intestine. The purposes of this article are to introduce the main transporters in the intestinal tract, to explain the transport mechanism and to summarize the advantages and disadvantages of the research methods of them.
ATP-Binding Cassette Transporters ; administration & dosage ; metabolism ; Animals ; Anion Transport Proteins ; administration & dosage ; metabolism ; Biological Availability ; Humans ; Intestinal Absorption ; Membrane Transport Proteins ; administration & dosage ; metabolism ; Peptide Transporter 1 ; Symporters ; administration & dosage ; metabolism