To establish single- and double-transfected transgenic cells stably expressing hMATE1, hMATE1 cDNA was cloned by RT-PCR from human cryopreserved kidney tissue, and subcloned into pcDNA3.1(+) plasmid by virtue of both HindIII and Kpn I restriction enzyme sites. Subsequently, the recombined pcDNA3.1(+)- hMATE1 plasmid was transfected into MDCK, MDCK-hOCT1 or MDCK-hOCT2 cells using Lipofectamine 2000 Reagent. After a 14-day-cultivation with hygromycin B at the concentration of 400 µg · mL(-1), all clones were screened with DAPI and MPP+ as substrates to identify the best candidate. The mRNA content of hMATE1, the cellular accumulation of metformin with or without cimetidine as inhibitor, or transportation of cimetidine was further valuated. The results showed that all of the three cell models over expressed hMATE1 mRNA. The cellular accumulation of metformin in MDCK-hMATE1 was 17.6 folds of the control cell, which was significantly inhibited by 100 µmol · L(-1) cimetidine. The transcellular transport parameter net efflux ratios of cimetidine across MDCK-hOCT1/hMATE1 and MDCK-hOCT2/hMATE1 monolayer were 17.5 and 3.65, respectively. In conclusion, cell models with good hMATE1 function have been established successfully, which can be applied to study the drug transport or drug-drug interaction involving hMATE1 alone or together with hOCT1/2 in vitro.
Animals ; Biological Transport ; Cimetidine ; pharmacology ; DNA, Complementary ; Dogs ; Drug Interactions ; Humans ; Madin Darby Canine Kidney Cells ; Metformin ; pharmacology ; Organic Cation Transport Proteins ; genetics ; metabolism ; Transfection

Acute renal failure with severe loin pain which develops after anaerobic exercise is rare. One of predisposing factors of exercise-induced acute renal failure is renal hypouricemia. Idiopathic renal hypouricemia is a genetic disorder characterized by hypouricemia with abnormally high renal tubular uric acid excretion. The mutation in SCL22A12 gene which encodes renal uric acid transporter, URAT1, is the known major cause of this disorder. We here described a 25-yr-old man showing idiopathic renal hypouricemia with G774A mutation in SCL22A12 who presented exercise-induced acute renal failure. There have been a few reports of mutational analysis in Korean idiopathic renal hypouricemia without acute renal failure. This is the first report of genetically diagnosed idiopathic renal hypouricemia with exercise-induced acute renal failure in Korea.
Acute Kidney Injury/*diagnosis/genetics ; Adult ; Amino Acid Substitution ; DNA Mutational Analysis ; Exercise ; Exons ; Humans ; Male ; Mutation ; Organic Anion Transporters/*genetics ; Organic Cation Transport Proteins/*genetics ; Renal Tubular Transport, Inborn Errors/etiology/*genetics ; Urinary Calculi/etiology/*genetics

Organic ion transporters are expressed in various tissues that transport endogenous and exogenous compounds including their metabolites. There are organic anion transporter (OAT), organic cation transporter (OCT), organic anion transporter like protein (OATLP) and organic cation transporter like (OCTL). Considering the variety of charged organic ionic compounds, the existence of numerous isoforms of organic ion transporters can be assumed. In the present study, we have searched for a new isoform in the expressed sequence tag (EST) database using human organic anion transporter 4 (hOAT4) amino acid sequence as a "query". We found a candidate clone (BC021449) from the mouse kidney cDNA library. This clone was identified as an ortholog of ORCTL3 or OCTL-1. The mOCTL1 cDNA consists of 2016 base pairs encoding 551 amino acid residues with 12 putative transmembrane domains. The deduced amino acid sequence of mOCTL1 showed 35 to 40% identity to those of the other members of the OATs and OCTs. According to the tissue distribution, examined by Northern blot analysis, about a 2.4-kb transcript of mOCTL1 was observed in the kidney. About a 90-kDa band was detected when Western blot analysis in the mouse kidney was done by using antibody against synthesized oligopeptide of mOCTL1. The immunohistochemical result showed that mOCTL1 was stained at the glomerulus (the parietal epithelial cells and podocytes), pars recta of proximal tubule, distal convoluted tubules, connecting tubules and collecting tubules. From these results, we conclude that mOCTL1 may be a candidate for an organic ion transporter isoform in the mouse kidney.
Amino Acid Sequence ; Animals ; Blotting, Western ; Gene Library ; Humans ; Immunohistochemistry ; Kidney/*metabolism ; Mice ; Molecular Sequence Data ; Organ Specificity ; Organic Cation Transport Proteins/genetics/*isolation & purification ; Organic Cation Transporter 1/genetics/*isolation & purification ; Protein Isoforms/isolation & purification

Objective: To investigate the expressions of solute carrier family 22 member 14 (SLC22A14) and sperm-associated antigen 6 (SPAG6) in the sperm of idiopathic asthenospermia men. METHODS: We collected semen samples from 50 idiopathic asthenozoospermia patients and another 50 normal sperm donors, purified the sperm by discontinuous density centrifugation on Percoll gradients, and then determined the mRNA and protein expressions of SLC22A14 and SPAG6 by RT-PCR and Western blot, respectively. RESULTS: Compared with the normal controls, the idiopathic asthenozoospermia patients showed significantly decreased mRNA expressions of SLC22A14 (0.77 ± 0.08 vs 0.53 ± 0.10, P<0.01) and SPAG6 (0.78 ± 0.09 vs0.52 ± 0.10 , P<0.01) and protein expressions of SLC22A14 (0.80 ± 0.09 vs 0.55 ± 0.10 , P<0.01) and SPAG6 (0.78 ± 0.09 vs 0.56 ± 0.09, P<0.01). CONCLUSIONS T The expressions of SLC22A14 and SPAG6 are reduced in the sperm of the patients with idiopathic asthenospermia, which may be one of the important causes of asthenospermia.
Asthenozoospermia ; metabolism ; Blotting, Western ; Ejaculation ; Humans ; Male ; Microtubule Proteins ; genetics ; metabolism ; Organic Cation Transport Proteins ; genetics ; metabolism ; Proteomics ; RNA, Messenger ; metabolism ; Sperm Motility ; Spermatozoa ; metabolism

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

Novel organic cation transporter-2 (OCTN2), a member of the organic cation transporter family, may transport carnitine and multiple organic cationic drugs. Thus OCTN2 possesses substantial roles in physiology and pharmacology. A number of researches have proven that many factors can regulate the expression and/or function of OCTN2 via different pathways, and then may affect the homeostasis and disposition of drugs. This paper reviews recent progresses in this field.
Animals ; Biological Transport ; Carnitine ; metabolism ; Carrier Proteins ; physiology ; Clofibrate ; pharmacology ; Colitis ; metabolism ; Homeostasis ; drug effects ; Humans ; Mutation ; Organic Cation Transport Proteins ; genetics ; metabolism ; physiology ; PPAR alpha ; agonists ; RNA, Messenger ; metabolism ; Solute Carrier Family 22 Member 5

The effects of mangiferin on uric acid excretion, kidney function and related renal transporters were investigated in hyperuricemic mice induced by potassium oxonate. Mice were divided into normal control group, and 5 hyperuricemic groups with model control, 50, 100, and 200 mg x kg(-1) mangiferin, and 5 mg x kg(-1) allopurinol. Mice were administered by gavage once daily with 250 mg x kg(-1) potassium oxonate for seven consecutive days to create the model. And 3 doses of mangiferin were orally initiated on the day 1 h after potassium oxonate was given, separately. Serum uric acid, creatinine and urea nitrogon levels, as well as urinary uric acid creatinine levels were measured. Mouse uromodulin (mUMOD) levels in serum, urine and kidney were determined by ELISA method. The mRNA and protein levels of related renal transporters were assayed by RT-PCR and Western blotting methods, respectively. Compared to model group, mangiferin significantly reduced serum uric acid, creatinine and urea nitrogon levels, increased 24 h uric acid and creatinine excretion, and fractional excretion of uric acid in hyperuricemic mice, exhibiting uric acid excretion enhancement and kidney function improvement. Mangiferin was found to down-regulate mRNA and protein levels of urate transporter 1 (mURAT1) and glucose transporter 9 (mGLUT9), as well as up-regulate organic anion transporter 1 (mOAT1) in the kidney of hyperuricemic mice. These findings suggested that mangiferin might enhance uric acid excretion and in turn reduce serum uric acid level through the decrease of uric acid reabsorption and the increase of uric acid secretion in hyperuricemic mice. Moreover, mangiferin remarkably up-regulated expression levels of renal organic cation and carnitine transporters (mOCT1, mOCT2, mOCTN1 and mOCTN2), increased urine mUMOD levels, as well as decreased serum and kidney mUMOD levels in hyperuricemic mice, which might be involved in mangiferin-mediated renal protective action.
Animals ; Blood Urea Nitrogen ; Carrier Proteins ; genetics ; metabolism ; Creatinine ; blood ; Glucose Transport Proteins, Facilitative ; genetics ; metabolism ; Hyperuricemia ; blood ; chemically induced ; physiopathology ; urine ; Kidney ; metabolism ; physiopathology ; Male ; Membrane Proteins ; genetics ; metabolism ; Mice ; Octamer Transcription Factor-1 ; genetics ; metabolism ; Organic Anion Transport Protein 1 ; genetics ; metabolism ; Organic Anion Transporters ; genetics ; metabolism ; Organic Cation Transport Proteins ; genetics ; metabolism ; Organic Cation Transporter 2 ; Oxonic Acid ; Protective Agents ; pharmacology ; RNA, Messenger ; metabolism ; Random Allocation ; Solute Carrier Family 22 Member 5 ; Uric Acid ; blood ; urine ; Uromodulin ; blood ; urine ; Xanthones ; pharmacology

Adenocarcinoma ; metabolism ; pathology ; Adenocarcinoma, Mucinous ; metabolism ; pathology ; Adenocarcinoma, Papillary ; metabolism ; pathology ; Carcinoma, Signet Ring Cell ; metabolism ; pathology ; Follow-Up Studies ; Gene Expression Regulation, Neoplastic ; Humans ; Lymphatic Metastasis ; Neoplasm Invasiveness ; Organic Cation Transport Proteins ; biosynthesis ; genetics ; Organic Cation Transporter 2 ; Osteopontin ; Prognosis ; RNA, Messenger ; biosynthesis ; genetics ; Sialoglycoproteins ; biosynthesis ; genetics ; Stomach Neoplasms ; metabolism ; pathology ; Survival Rate

OBJECTIVETo explore the mechanism of L-Carnitine transport and the expression of OCTN2 mRNA in the human epididymis so as to provide a theoretical basis for male contraception.

METHODSWe collected specimens from human epididymides and determined the expressions of OCTN2 mRNA in the caput, corpus and cauda of the epididymis by RT-PCR.

RESULTSOCTN2 mRNA was expressed in the caput, corpus and cauda of the epididymis.

CONCLUSIONThe human epididymis may rely on OCTN2 for transporting L-Carnitine into the epididymal duct to promote sperm maturation. With the accumulation of information on OCTN2 in the human epididymis, OCTN2 will become a new molecular target for researches on male contraception.

Contraception ; methods ; Epididymis ; metabolism ; Gene Expression Profiling ; Gene Expression Regulation ; Humans ; Male ; Organic Cation Transport Proteins ; genetics ; RNA, Messenger ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Solute Carrier Family 22 Member 5

OBJECTIVETo investigate the association of the exon 8 and intron 8 polymorphisms of the human urate transporter 1 gene SLC22A12 with primary hyperuricemia (HUA) in Chinese Han population.

METHODSGenomic DNA from 215 individuals with HUA and 323 controls was extracted. The exon 8 and intron 8 of the SLC22A12 gene was amplified by polymerase chain reaction (PCR). PCR product was sequenced directly. Single nucleotide polymorphisms (SNPs) were detected and the association of the SNPs with primary HUA was assessed.

RESULTS(1) Two SNPs were identified, they were T1309C located in exon 8 (rs7932775) and -103A to G located in intron 8. Pairwise linkage disequilibrium analysis displayed an absolute linkage disequilibrium between the two SNPs (D'= 1). (2) The minor allele frequencies for both SNPs were 51.9% in HUA patients, which were significantly different from that of controls (42.4%)(P< 0.01). (3) The genotype frequencies of GG+ GA and CC+ CT in HUA patients were significantly higher than that in controls (80.0% vs. 69.0%, P< 0.01). (4) Individuals of both GG+ GA and CC+ CT genotypes had 1.79 fold increase of HUA risk (OR= 1.794, 95%CI: 1.19-2.70).

CONCLUSIONThese findings indicated that T1309C and -103A to G polymorphisms of the SLC22A12 gene were associated with primary HUA in Chinese Han population.

Adult ; Aged ; Aged, 80 and over ; Asian Continental Ancestry Group ; genetics ; Base Sequence ; Case-Control Studies ; China ; ethnology ; Ethnic Groups ; genetics ; Exons ; genetics ; Female ; Gene Frequency ; Genotype ; Humans ; Hyperuricemia ; genetics ; Introns ; genetics ; Linkage Disequilibrium ; Male ; Middle Aged ; Molecular Sequence Data ; Organic Anion Transporters ; genetics ; Organic Cation Transport Proteins ; genetics ; Polymorphism, Single Nucleotide ; genetics