Search results for "Organic Anion Transporters"
showing 10 items of 16 documents
Cloning and characterization of the genes encoding the malolactic enzyme and the malate permease of Leuconostoc oenos
1996
Using degenerated primers from conserved regions of the protein sequences of malic enzymes, we amplified a 324-bp DNA fragment by PCR from Leuconostoc oenos and used this fragment as a probe for screening a Leuconostoc oenos genomic bank. Of the 2,990 clones in the genomic bank examined, 7 with overlapping fragments were isolated by performing colony hybridization experiments. Sequencing 3,453 bp from overlapping fragments revealed two open reading frames that were 1,623 and 942 nucleotides long and were followed by a putative terminator structure. The first deduced protein (molecular weight, 59,118) is very similar (level of similarity, 66%) to the malolactic enzyme of Lactococcus lactis; …
Anti-hyperuricemic and nephroprotective effects of extracts from Chaenomeles sinensis (Thouin) Koehne in hyperuricemic mice
2018
Clinically, Chaenomeles sinensis (Thouin) Koehne (C. sinensis) has been used to treat hyperuricemia and gout. However, the exact mechanism of action is still unknown. In the present study, the ethyl acetate fraction of C. sinensis fruit extract (CSF-E) was separated. Potassium oxonate (PO)-induced hyperuricemic mice and normal mice were administered with CSF-E at 60, 120 and 180 mg kg-1, respectively for 7 days. Serum uric acid, creatinine and BUN levels, liver oxidative damage, and serum and hepatic XOD activities were primarily measured using assay kits. The evaluation of its nephroprotective effects was carried out by renal histopathological analysis. Simultaneously, renal protein levels…
Tiagabine, a gamma-amino-butyric acid transporter inhibitor impairs spatial learning of rats in the Morris water-maze.
2002
Abstract γ-Amino-butyric acid (GABA) is cleaved from the synaptic cleft by uptake via specific transporters. Inhibition of such transporters increases the effectiveness of physiologically released GABA. Increased GABAergic neurotransmission has an impact on learning and memory. Therefore, effects of tiagabine, a GABA-transporter inhibitor, were investigated on spatial orientation in the Morris water-maze. Rats were given four training trials per day for 4 days and a probe trial without platform on the 5th day. Compared to saline treated rats, rats treated daily with 20 mg/kg tiagabine showed impaired learning during the acquisition trials. Retrieval was impaired in rats treated only at the …
Expression of Putative Fatty Acid Transporter Genes Are Regulated by Peroxisome Proliferator-activated Receptor α and γ Activators in a Tissue- and I…
1998
Regulation of gene expression of three putative long-chain fatty acid transport proteins, fatty acid translocase (FAT), mitochondrial aspartate aminotransferase (mAspAT), and fatty acid transport protein (FATP), by drugs that activate peroxisome proliferator-activated receptor (PPAR) alpha and gamma were studied using normal and obese mice and rat hepatoma cells. FAT mRNA was induced in liver and intestine of normal mice and in hepatoma cells to various extents only by PPARalpha-activating drugs. FATP mRNA was similarly induced in liver, but to a lesser extent in intestine. The induction time course in the liver was slower for FAT and FATP mRNA than that of an mRNA encoding a peroxisomal en…
Both cholestatic and steatotic drugs trigger extensive alterations in the mRNA level of biliary transporters in rat hepatocytes: Application to devel…
2016
Disruption of the vectorial bile acid transport in the liver is a key feature of cholestatic drugs, although many causal and mechanistic aspects are still unknown. The aim of the present study was to explore if cholestatic drugs can repress or induce the expression of hepatic transporters. To this end, sandwich-cultured rat hepatocytes were treated with cholestatic and non-cholestatic (steatotic, non-hepatotoxic, etc.) drugs and the mRNA expression of 10 uptake and efflux biliary transporters was measured. Results evidenced that all cholestatic drugs cause extensive alterations in the mRNA expression of most biliary transporters. Surprisingly, nearly all steatotic drugs also affected the ex…
Genotype and Allele Frequencies of Drug-Metabolizing Enzymes and Drug Transporter Genes Affecting Immunosuppressants in the Spanish White Population
2013
Interpatient variability in drug response can be widely explained by genetically determined differences in metabolizing enzymes, drug transporters, and drug targets, leading to different pharmacokinetic and/or pharmacodynamic behaviors of drugs. Genetic variations affect or do not affect drug responses depending on their influence on protein activity and the relevance of such proteins in the pathway of the drug. Also, the frequency of such genetic variations differs among populations, so the clinical relevance of a specific variation is not the same in all of them. In this study, a panel of 33 single nucleotide polymorphisms in 14 different genes (ABCB1, ABCC2, ABCG2, CYP2B6, CYP2C19, CYP2C…
The inhibitory neural circuitry as target of antiepileptic drugs.
2001
Impairments and defects in the inhibitory neurotransmission in the CNS can contribute to various seizure disorders, i.e., gamma-aminobutyric acid (GABA) and glycine as the main inhibitory neurotransmitters in the brain play a crucial role in some forms of epilepsy. Recent advances in deciphering the molecular basis of the GABAergic and glycinergic systems has been achieved by means of cloning techniques and gene targeting strategies in animals, contributing to the understanding of drug action. As well, several anticonvulsive substances emerged which target key molecules of the inhibitory systems. Employment of recombinant expression systems, including, but not restricted to the inhibitory c…
Liver and Statins: A Critical Appraisal of the Evidence.
2019
Adverse drug reactions (ADRs) represent an important cause of morbidity and mortality worldwide. Statins are a class of drugs whose main adverse effects are drug-induced liver injury (DILI) and myopathy. Some of these may be predictable, due to their pharmacokinetic and pharmacodynamic properties, while others, unfortunately, are idiosyncratic. Genetic factors may also influence patient susceptibility to DILI and myopathy in the case of statins. This review will first discuss the role of statins in cardiovascular disease treatment and prevention and the underlying mechanisms of action. Furthermore, to explore the susceptibility of statin-induced adverse events such as myopathy and hepatoto…
Anxiolytic-like effects of acute and chronic GABA transporter inhibition in rats.
2002
Acute GABA transporter inhibition can induce anxiolytic-like behaviors. The present analysis addressed whether chronic treatment (23 days via drinking water) with a GABA transporter inhibitor affects rat behavior similar to acute treatment and interferes with additional benzodiazepine-receptor agonistic treatment. Seventy-one rats divided into seven groups were acutely treated with either vehicle, diazepam (2 mg/kg), zolpidem (0.05 mg/kg), tiagabine (19 mg/kg) or chronically with tiagabine with or without acute diazepam or zolpidem. Animals were behaviorally characterized in an elevated plus-maze. None of the treatments induced changes in the activity of the animals. Acute and chronic treat…
Uric Acid Metabolism in Pre-hypertension and the Metabolic Syndrome
2014
In humans uric acid (UA) is the end product of degradation of purines. The handling of UA by the renal system is a complex process which is not fully understood. To date, several urate transporters in the renal proximal tubule have been identified. Among them, urate transporter 1 (URAT1) and a glucose transporter 9 (GLUT9) are considered of greater importance, as potential targets for treatment of hyperuricemia and the potential associated cardio-metabolic risk. Therefore, the recognition of the metabolic pathway of UA and elucidation of occurrence of hyperuricemia may provide important insights about the relationship between UA, pre-hypertension (preHT) and the metabolic syndrome (MetS). W…