Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 446
Filter
1.
Urol J ; 15(2): 38-43, 2018 03 18.
Article in English | MEDLINE | ID: mdl-29299890

ABSTRACT

PURPOSE: Fibrates are drugs widely used for the treatment of hyperlipidemic disorders. Previous studies on a novel analogue of clofibrate, called silafibrate, have shown good lipid lowering effects. This study was designed to assess the role of silafibrate as a peroxisome proliferator-activated receptors (PPARs) agonist on sperm health and spermatogenesis in adult male rats. MATERIAL AND METHODS: Seventy male Wistar rats were randomly allocated into 7 groups: Cl-10, Cl-20, and Cl-40 mg/kg/day (clofibrate); Si-10, Si-20, and Si-40 mg/kg/day (silafibrate); and C, control. After a 28-day treatment, all rats were euthanized. Blood samples were taken for determination of testosterone, total antioxidant capacity, levels of malondialdehyde, and oxidized low-density lipoprotein. Reproductive organs were dissected and spermatozoa collected from the epididymis for analysis. RESULT: Sperm parameters (count, motility, viability, and morphology) and total serum testosterone decreased significantly in clofibrate-treated (20 and 40 mg/kg) rats (P < 0.05) as compared with normal rats. CONCLUSION: We conclude that PPARs agonists have significant adverse effect on sperm viability, motility, and total serum testosterone, and could be harmful for sperm parameters and male reproductive function in rats.


Subject(s)
Clofibrate/analogs & derivatives , Clofibrate/pharmacology , Hypolipidemic Agents/pharmacology , Sperm Count , Sperm Motility/drug effects , Spermatozoa/drug effects , Animals , Cell Survival/drug effects , Follicle Stimulating Hormone/blood , Lipoproteins, LDL/blood , Luteinizing Hormone/blood , Male , Malondialdehyde/blood , Peroxisome Proliferator-Activated Receptors/agonists , Random Allocation , Rats , Spermatozoa/pathology , Spermatozoa/physiology , Testosterone/blood
2.
Arh Hig Rada Toksikol ; 65(2): 169-78, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24706421

ABSTRACT

Acetaminophen (N-acetyl para amino phenol, APAP) is a widely used antipyretic and analgesic drug responsible for various drug-induced liver injuries. This study evaluated APAP-induced toxicity in isolated rat hepatocytes alongside the protective effects of silafibrate and N-acetyl cysteine (NAC). Hepatocytes were isolated from male Sprague-Dawley rats by collagenase enzyme perfusion via the portal vein. This technique is based on liver perfusion with collagenase after removing calcium ions (Ca2+) with a chelator. Cells were treated with different concentrations of APAP, silafibrate, and NAC. Cell death, reactive oxygen species (ROS) formation, lipid peroxidation, and mitochondrial depolarisation were measured as toxicity markers. ROS formation and lipid peroxidation occurred after APAP administration to rat hepatocytes. APAP caused mitochondrial depolarisation in isolated cells. Administration of silafibrate (200 µmol L-1) and/or NAC (200 µmol L-1) reduced the ROS formation, lipid peroxidation, and mitochondrial depolarisation caused by APAP. Cytotoxicity induced by APAP in rat hepatocytes was mediated by oxidative stress. In addition, APAP seemed to target cellular mitochondria during hepatocyte damage. The protective properties of silafibrate and/or NAC against APAP­induced hepatic injury may have involved the induction of antioxidant enzymes, protection against oxidative stress and inflammatory responses, and alteration in cellular glutathione content.


Subject(s)
Acetaminophen/adverse effects , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Chemical and Drug Induced Liver Injury/physiopathology , Clofibrate/analogs & derivatives , Clofibrate/pharmacology , Cytoprotection , Hepatocytes/drug effects , Acetaminophen/pharmacology , Animals , Male , Rats , Rats, Sprague-Dawley
3.
J Pharm Sci ; 101(4): 1555-69, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22246648

ABSTRACT

Isopropyl 2-[4-(4-chlorobenzoyl)-phenoxy]-2-methylpropanoic acid and isopropyl 2-(4-chlorophenoxy)-2-methylpropanoate, also known as fenofibrate and isopropyl (iPr) clofibrate, are hypolipidemic agents of the fibrate family. In a previously reported triclinic structure of fenofibrate (polymorph I), the methyl groups of the iPr moiety are located symmetrically about the carboxylate group. We report a new monoclinic form (polymorph II) of fenofibrate and a first structural description of iPr clofibrate, and in these the methyl groups are placed asymmetrically about the carboxylate group. In particular, the dihedral (torsion) angle between the hydrogen atom on the secondary C and the C atom of the carboxyl group makes a 2.74° angle about the ester O···C bond in the symmetric fenofibrate structure of polymorph I, whereas the same dihedral angle is 45.94° in polymorph II and -30.9° in the crystal structure of iPr clofibrate. Gas-phase density functional theory (DFT) geometry minimizations of fenofibrate and iPr clofibrate result in lowest energy conformations for both molecules with a value of about ±30° for this same angle between the OC-O-C plane and the C-H bond of the iPr group. A survey of crystal structures containing an iPr ester group reveals that the asymmetric conformation is predominant. Although the hydrogen atom on the secondary C atom of the iPr group is located at a comparable distance from the carbonyl oxygen in the symmetric and asymmetric fenofibrate (2.52 and 2.28 Å) and the iPr clofibrate (2.36 Å) structures, this hydrogen atom participates in a puckered five-membered ring arrangement in the latter two that is unlike the planar arrangement found in symmetric fenofibrate (polymorph I). Polar molecular surface area values indicate fenofibrate and iPr clofibrate are less able to act as acceptors of hydrogen bonds than their corresponding acid derivatives. Surface area calculations show that dynamic polar molecular surface area values of the iPr esters of the fibrates are lower than those of their acids, implying that the fibrates have better membrane permeability and a higher absorbability and hence are better prodrugs when these agents need to be orally administered.


Subject(s)
Clofibrate/analogs & derivatives , Fenofibrate/chemistry , Fibric Acids/chemistry , Hypolipidemic Agents/chemistry , Drug Design , Molecular Conformation , Structure-Activity Relationship , Surface Properties
5.
Eur J Pharmacol ; 576(1-3): 114-21, 2007 Dec 08.
Article in English | MEDLINE | ID: mdl-17764671

ABSTRACT

The study was designed to characterise the influence of a novel acyl-CoA:cholesterol acyltransferase inhibitor, VULM 1457, on the severity of myocardial ischaemia-reperfusion injury in a model of diabetes mellitus and hypercholesterolaemia induced by co-administration of streptozotocin and a high fat-cholesterol diet. We used Langendorff-perfused rat hearts to measure the size of myocardial infarction after 30 min of regional ischaemia, followed by a 2-h reperfusion period, and open-chest rats were exposed to 6 min of ischaemia and 10 min of reperfusion to analyse ventricular arrhythmias. In addition to the high fat-cholesterol diet, VULM 1457 was administered to the diabetic-hypercholesterolaemic rats for 5 days. Decreased plasma and liver cholesterol levels and a significantly reduced occurrence of ventricular fibrillation (29% vs. 100%, P<0.01), determined via the mean number and duration of episodes (0.6+/-0.4 and 2.1+/-1.4 s vs. 2.8+/-0.8 and 53.5+/-14.4 s in diabetic-hypercholesterolaemic rats, both P<0.01), were observed in these animals. Lethal ventricular fibrillation was suppressed, and arrhythmia severity was also significantly decreased in these animals as compared to the non-treated animals (2.9+/-0.6 vs. 4.9+/-0.2; P<0.05). A smaller infarct size, normalised to the size of area at risk, was observed in the treated diabetic-hypercholesterolaemic group as compared to the non-treated group (16.3+/-1.9% vs. 37.3+/-3.1%; P<0.01). Aside from remarkable hypolipidaemic activity, VULM 1457 improved the overall myocardial ischaemia-reperfusion injury outcomes in the diabetic-hypercholesterolaemic rats by suppressing arrhythmogenesis as well as by reducing myocardial necrosis.


Subject(s)
Anti-Arrhythmia Agents/pharmacology , Clofibrate/analogs & derivatives , Hypolipidemic Agents/pharmacology , Reperfusion Injury/prevention & control , Sterol O-Acyltransferase/antagonists & inhibitors , Animals , Cholesterol, Dietary/administration & dosage , Clofibrate/pharmacology , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/physiopathology , Hypercholesterolemia/complications , Hypercholesterolemia/drug therapy , Hypercholesterolemia/etiology , Hypercholesterolemia/physiopathology , Male , Myocardial Infarction/drug therapy , Myocardial Infarction/etiology , Myocardial Infarction/physiopathology , Rats , Rats, Wistar
6.
Gen Physiol Biophys ; 26(4): 254-9, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18281742

ABSTRACT

Acyl-coenzyme A: cholesterol O-acyltransferase (ACAT) catalyzes the formation of cholesterol/fatty acyl-coenzyme A esters. Accumulation of cholesterol esters leads to pathological changes connected with atherosclerosis. We have evaluated effects of a newly synthesized ACAT inhibitor, 1-(2,6-diisopropyl-phenyl)-3-[4-(4'-nitrophenylthio)phenyl] urea (VULM 1457), on serum lipid (cholesterol and triglycerides) levels and velocity of red blood cells (RBC) in non-diabetic and diabetic hamsters fed on high cholesterol-lipid (HCHL) diet during 3 months. The VULM 1457 effects on the paw microcirculation were assessed using capillary microscopy by measuring (RBC) velocity in vivo. Hamsters fed on HCHL diet became hypercholesterolemic with a dramatic increase in serum lipids accompanied with significantly decreased RBC velocity. Diabetic hamsters fed on HCHL diet had further increased serum lipids with reduction of RBC velocity. The VULM 1457 inhibitor lowered cholesterol levels in both non-diabetic and diabetic hamsters fed on HCHL diet. The greater VULM 1457 effect was shown in diabetic hamsters fed on HCHL diet where VULM 1457 expressed hypotriglycerides effects, too. An improved RBC velocity-pronounced effect was observed in diabetic hamsters fed on HCHL diet treated with VULM 1457. These results suggest that the ACAT inhibitor, VULM 1457, is a prospective hypolipidemic and anti-atherogenic drug which treats diabetes.


Subject(s)
Cholesterol/blood , Clofibrate/analogs & derivatives , Diabetes Mellitus/metabolism , Dietary Fats/pharmacology , Erythrocytes/drug effects , Lipids/blood , Sterol O-Acyltransferase/antagonists & inhibitors , Animals , Blood Flow Velocity/drug effects , Blood Glucose/analysis , Cholesterol/analysis , Cholesterol/metabolism , Cholesterol, Dietary/pharmacology , Clofibrate/pharmacology , Cricetinae , Diabetes Mellitus/physiopathology , Diet , Erythrocytes/physiology , Male , Sterol O-Acyltransferase/metabolism , Triglycerides/analysis , Triglycerides/blood
7.
Pharmazie ; 61(9): 807-8, 2006 Sep.
Article in English | MEDLINE | ID: mdl-17020164

ABSTRACT

This study examined the effects of simvastatin (10 mg/ kg) and VULM 1457 (50 mg/kg), an ACAT inhibitor, in the heart model of 6 min ischemia followed by 10 min reperfusion injury in the diabetic-hypercholesterolaemic (DM-HCH) rats. In the DM-HCH rats, the incidence of ventricular tachycardia (VT) had a tendency to be increased, while ventricular fibrillation (VF) occurred in all diseased rats (p < 0.01). Simvastatin and VULM 1457 with the shown hypolipidemic effect, significantly (p < 0.01) suppressed a formation of VF (38% and 29%; respectively).


Subject(s)
Clofibrate/analogs & derivatives , Diabetes Mellitus, Experimental/complications , Enzyme Inhibitors/therapeutic use , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Hypercholesterolemia/complications , Myocardial Reperfusion Injury/prevention & control , Reperfusion Injury/prevention & control , Simvastatin/therapeutic use , Sterol O-Acyltransferase/antagonists & inhibitors , Animals , Arrhythmias, Cardiac/etiology , Arrhythmias, Cardiac/prevention & control , Blood Glucose/metabolism , Cholesterol/blood , Cholesterol/metabolism , Cholesterol, Dietary , Clofibrate/therapeutic use , Diabetes Mellitus, Experimental/physiopathology , Hypercholesterolemia/chemically induced , Hypercholesterolemia/physiopathology , Male , Myocardial Reperfusion Injury/pathology , Rats , Rats, Wistar , Reperfusion Injury/pathology
8.
Pharmazie ; 60(9): 714-5, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16222877

ABSTRACT

The use of inhibitors of enzyme acyl-CoA: cholesterol acyltransferase (ACAT) seems to be a novel potential approach for a therapeutic treatment of dyslipidaemias and atherosclerosis. VULM 1457 is an ACAT inhibitor, which has expressed potent hypolipidemic and antiatherosclerotic effects in previous studies. In this study, we used streptozocin-induced diabetic rats, which were fed a fat-cholesterol diet to evaluate the affect of VULM 1457 on the atherogenic lipids levels in both plasma and liver. VULM 1457, with a slight influence on triglyceride levels, significantly reduced plasma and hepatic cholesterol concentrations (p < 0.05, p < 0.001; respectively) in the diabetic-hypercholesterolaemic rats.


Subject(s)
Clofibrate/analogs & derivatives , Diabetes Mellitus, Experimental/drug therapy , Enzyme Inhibitors/pharmacology , Hypercholesterolemia/drug therapy , Hypolipidemic Agents , Sterol O-Acyltransferase/antagonists & inhibitors , Animals , Blood Glucose/metabolism , Cholesterol/blood , Cholesterol/metabolism , Cholesterol, Dietary/pharmacology , Clofibrate/pharmacology , Diabetes Mellitus, Experimental/blood , Dietary Fats/pharmacology , Hypercholesterolemia/blood , Liver/drug effects , Liver/metabolism , Rats , Rats, Wistar , Triglycerides/blood
9.
Eur J Med Chem ; 40(2): 143-54, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15694649

ABSTRACT

Clofibrate is a lipid-profile modifying agent belonging to the fibrate class of drugs. Fibrates are known to exhibit their beneficial effects by activating peroxisome proliferator-activated receptor-alpha (PPARalpha) and used in the treatment of dyslipidemia and atherosclerosis and for the prevention of heart failure. Hereby, the preparation of two new sets of clofibrate analogues, ethyl 2-(4-chlorophenoxy)-3-oxoalkanoates and ethyl 2-(4-chlorophenoxy)-3-hydroxyalkanoates is described starting from commercially available 3-oxoalkanoates in fair to good yields. Treatment of 3-oxoalkanoates with SO2Cl2 yielded the corresponding 2-chloro-3-oxoalkanoates, that were then converted into 2-(4-chlorophenoxy)-3-oxoalkanoates by reacting with sodium or caesium 4-chlorophenate. Reduction of the keto group with NaBH4 afforded the corresponding 2-(4-chlorophenoxy)-3-hydroxyalkanoates in very high yields and with variable diastereoselectivity. Biological evaluation of the compounds was performed by a transactivation assay in a transiently transfected monkey kidney fibroblast cell line. The newly synthesised clofibrate analogues failed to show noticeable levels of PPAR activation at concentrations where clofibrate showed an evident activity, suggesting that the structural modifications caused the loss of PPAR activity.


Subject(s)
Clofibrate/chemical synthesis , Esters/chemical synthesis , Hypolipidemic Agents/chemical synthesis , PPAR alpha/agonists , Transcription Factors/drug effects , Animals , Cell Line , Clofibrate/analogs & derivatives , Clofibrate/pharmacology , Esters/pharmacology , Fibroblasts/cytology , Haplorhini , Hypolipidemic Agents/pharmacology , Kidney/cytology , Models, Chemical , Stereoisomerism , Transcription Factors/metabolism
10.
Gen Physiol Biophys ; 24(4): 397-409, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16474185

ABSTRACT

Acyl-CoA:cholesterol acyltransferase (ACAT) is an important enzyme in the pathways of cholesterol esterification. It has been shown that new ACAT inhibitor 1-(2,6-diisopropyl-phenyl)-3-[4-(4'-nitrophenylthio)phenyl] urea (VULM1457) significantly reduced atherogenic activity in animal experimental atherosclerosis. Proliferative hormone adrenomedullin (AM) has been shown to be released in response to hypoxia, however, its role in cellular protection has remained elusive. The effect of increased local production of AM in cells and resultant down-regulation of AM receptors has not been investigated yet. We hypothesized that increased expression of AM in hypoxic cells was the result of excessive AM production with resultant AM receptor down-regulation, surface-membrane protein degradation and that the new specific ACAT inhibitor would reduce AM induction in hypoxia and thus proliferation of cells. In order to investigate specific cellular AM signaling and protection induced by VULM1457, we characterized specific surface-membrane [125I]AM receptors expressed on cells, evaluated AM secretion (RIA assays), AM mRNA expression in cultured cells (RT-PCR analysis) and proliferation (incorporation of [3H]thymidine) in control, hypoxic and metabolically stressed human hepatoblastoma cell lines exposed to gradually increasing concentrations of VULM1457. The new ACAT inhibitor VULM1457 in concentration 0.03 and 0.1 micromol/l significantly down-regulated specific AM receptors on HepG2 cells, reduced AM secretion of HepG2 cells exposed to hypoxia. These results suggest that VULM1457, as new member of ACAT family of inhibitors could negatively regulate cell proliferation induced by AM, which may correlate with down-regulation of membrane-bound AM receptors on HepG2 cells, and moreover, with the induction and expression of AM in hypoxia.


Subject(s)
Carcinoma, Hepatocellular/metabolism , Clofibrate/analogs & derivatives , Peptides/metabolism , Receptors, Peptide/metabolism , Sterol O-Acyltransferase/antagonists & inhibitors , Adrenomedullin , Cell Hypoxia/drug effects , Cell Line, Tumor , Clofibrate/administration & dosage , Dose-Response Relationship, Drug , Down-Regulation/drug effects , Humans , Receptors, Adrenomedullin
11.
Yakugaku Zasshi ; 122(11): 909-18, 2002 Nov.
Article in Japanese | MEDLINE | ID: mdl-12440149

ABSTRACT

Insulin resistance is a characteristic feature of type II diabetes as well as obesity. This insulin resistant state at the peripheral tissue level causes impaired glucose utilization, leading to hyperglycemia. Studies of antidiabetic agents by Takeda originated more than three decades ago when KK mice were introduced, followed by the development of a highly insulin-resistant animal model, KKAy mice. The first 2,4-thiazolidinedione derivative AL-321, which exhibited hypoglycemic effects in KKAy mice, was discovered by modification of the hypolipidemic agent AL-294 as a lead compound. Extensive structure-activity relationship studies on the analogues of AL-321 led to the selection of ciglitazone (ADD-3878) as a candidate for clinical evaluation. Ciglitazone, a prototypical compound in the series, was shown to normalize hyperglycemia, hyperinsulinemia, and hypertriglyceridemia in various insulin-resistant animal models without altering normoglycemia in nondiabetic animal models. However, it appeared that a more potent compound was needed for further clinical evaluation of this class of compound. Further study of this series of compounds led to the finding of pioglitazone (AD-4833) as a promising clinical candidate. Pioglitazone clearly ameliorates the abnormal glucose and lipid metabolism in diabetic patients and was marketed in the USA in August 1999 for the treatment of type II diabetes. Pioglitazone is now marketed in more than 40 countries world wide. Historical aspects of our studies on pioglitazone and its biological activities are described.


Subject(s)
Clofibrate/analogs & derivatives , Drug Design , Hypoglycemic Agents , Insulin Resistance , Thiazoles , Thiazolidinediones , Animals , Clinical Trials as Topic , Diabetes Mellitus/drug therapy , Diabetes Mellitus/physiopathology , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/physiopathology , Humans , Hypoglycemic Agents/therapeutic use , Mice , Pioglitazone , Thiazoles/therapeutic use
13.
Nihon Arukoru Yakubutsu Igakkai Zasshi ; 35(5): 306-20, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11144151

ABSTRACT

The fibrates are widely used for the reduction of high triglyceride levels. The fibrates act as the peroxisome proliferator-activated receptor alpha ligands to regulate the transcription of large number of genes that affect lipoprotein and fatty acid metabolism. The male rats of Wistar strain, simfibrate-treated (100 mg/kg, 200 mg/kg) or clinofibrate-treated (50 mg/kg, 100 mg/kg), were given ethanol (2 g/kg) orally. Blood ethanol levels on the simfibrate groups (100 mg/kg, 200 mg/kg) were significantly lower than the control groups (p < 0.01). The clinofibrate groups (100 mg/kg) were also lower than the controls (p < 0.05). The fatty acid beta-oxidation activity of liver peroxisome in simfibrate-treated (200 mg/kg) or clinofibrate-treated (100 mg/kg) rats for single administration (2.5 hours before the measurement) and twice administrations (20 and 1 hours before the measurement) were assayed. The activity ratio was 168% in simfibrate (p < 0.05), 146% in clinofibrate in single administration, and 388% in simfibrate (p < 0.01), 200% in clinofibrate (p < 0.01) in twice administrations. Alcohol dehydrogenase of cytosol and aldehyde dehydrogenase of cytosol, microsome and mitochondria in the liver were not induced by these fibrates. These results were suggested that simfibrate and clinofibrate induced beta-oxidation by peroxisome and increased H2O2 production, which led to augmented ethanol metabolism by catalase.


Subject(s)
Clofibrate/analogs & derivatives , Clofibrate/pharmacology , Ethanol/metabolism , Hypolipidemic Agents/pharmacology , Phenoxyacetates/pharmacology , Animals , Dose-Response Relationship, Drug , Hydrogen Peroxide/metabolism , Liver/cytology , Male , Oxidation-Reduction/drug effects , Peroxisomes/metabolism , Rats , Rats, Wistar , Stimulation, Chemical
14.
J Pharmacol Exp Ther ; 285(3): 1096-103, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9618412

ABSTRACT

The NADP+-dependent dehydrogenase activity of a predominant isoenzyme of human liver 3alpha-hydroxysteroid dehydrogenase was activated by antihyperlipidemic drugs, such as bezafibrate and clinofibrate, and by clofibric acid and fenofibric acid (active metabolites of clofibrate and fenofibrate, respectively). The optimal pH of the activation by the drugs was about 7.5, and the concentrations giving maximum stimulation (1.8- to 2.4-fold) were 100, 50, 400 and 50 microM for bezafibrate, clinofibrate, clofibric acid and fenofibric acid, respectively. Clofibrate and fenofibrate acted as weak inhibitors, and the clofibric acid derivatives that lack the chloro group, methyl group on the alpha-carbon or carboxyl group greatly decreased the stimulatory effects. The activation by the drugs increased both Km and kcat (turnover number) values for the coenzyme and substrates. Kinetic analysis with respect to NADP+ showed that bezafibrate, clinofibrate, clofibric acid and fenofibric acid were nonessential activators showing dissociation constants of 32, 6, 103 and 11 microM, respectively. The combined activators experiments with one of the above drugs and sulfobromophthalein, a known activator specific for this enzyme, and comparison of their effects on the activities of mutant enzymes (with Met replacing Lys-270 or Arg-276) indicated that sulfobromophthalein and the drugs bind to an identical site on the enzyme. These results suggest that the long-term therapy with the antihyperlipidemic drugs influences the metabolism of steroid hormones, bile acids and several ketone-containing drugs mediated by the enzyme.


Subject(s)
Hydroxysteroid Dehydrogenases/drug effects , Hypolipidemic Agents/pharmacology , Liver/enzymology , Alcohol Oxidoreductases/drug effects , Alcohol Oxidoreductases/metabolism , Aldehyde Reductase , Aldo-Keto Reductases , Binding Sites , Clofibrate/analogs & derivatives , Clofibrate/pharmacology , Clofibric Acid/pharmacology , Dose-Response Relationship, Drug , Enzyme Activation/drug effects , Fenofibrate/pharmacology , Humans , Hydrogen-Ion Concentration , Hydroxysteroid Dehydrogenases/isolation & purification , Hydroxysteroid Dehydrogenases/metabolism , Liver/drug effects
15.
Prep Biochem Biotechnol ; 28(1): 37-47, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9516641

ABSTRACT

Furosemide 1-O-acyl glucuronide (Fgnd) was extracted from the urine following oral administration of furosemide. The crude Fgnd was applied to micronized Amberlite XAD-2 column (2.5 cm i.d. x 90 cm length, 75-500 microns particle size). The purified Fgnd was identified by mass spectrometry and beta-glucuronidase treatment. This method was also applicable to the purification of glucuronide of tolmetin (nonsteroidal anti-inflammatory drug, NSAID), suggesting that it was applicable to the other NSAIDs, most of which were known to be metabolized to acyl-glucuronides.


Subject(s)
Furosemide/analogs & derivatives , Glucuronates/urine , Anti-Inflammatory Agents, Non-Steroidal/analysis , Benzimidazoles/analysis , Chromatography, High Pressure Liquid/methods , Chromatography, Ion Exchange/methods , Clofibrate/analogs & derivatives , Clofibrate/analysis , Flufenamic Acid/analogs & derivatives , Flufenamic Acid/analysis , Furosemide/urine , Glucuronidase/metabolism , Indomethacin/analogs & derivatives , Indomethacin/analysis , Mass Spectrometry , Molecular Structure , Probenecid/analogs & derivatives , Probenecid/analysis , Tolmetin/analogs & derivatives , Tolmetin/analysis
16.
Jpn J Pharmacol ; 70(1): 25-33, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8822086

ABSTRACT

The possibility that hyperlipidemia and an increase of mononuclear cells in the glomeruli could participate in the pathogenesis of minimal change glomerulopathy was evaluated in puromycin aminonucleoside (PAN) nephrosis in rats. Significant increases in intraglomerular CD4-, IL-2-receptor (R)- and ED-1-positive cells were found in PAN rats. Urinary protein excretion and mononuclear cells in the glomeruli of 1% cholesterol diet-fed rats significantly increased, compared with standard diet feeding. Moreover, administration of a subnephrogenic dose of PAN in cholesterol diet-fed rats substantially increased urinary protein excretion and mononuclear cells in the glomeruli. Additionally, antihyperlipidemia agents and immunosuppressive agents prevented urinary protein excretion and increases of CD4-, IL-2R- and ED-1-positive cells in the glomeruli of PAN nephrotic rats. Monoclonal antibodies directed against these cells also prevented urinary protein excretion. These results suggest that CD4-, IL-2R- and ED-1-positive cells and hyperlipidemia are involved in the progression, but not the pathogenesis, of PAN.


Subject(s)
Hyperlipidemias/complications , Kidney Glomerulus/pathology , Leukocytes, Mononuclear/pathology , Nephrosis/pathology , Puromycin Aminonucleoside , Animals , Anticholesteremic Agents/pharmacology , Azathioprine/pharmacology , CD4-Positive T-Lymphocytes/metabolism , CD4-Positive T-Lymphocytes/pathology , Cholestyramine Resin/pharmacology , Clofibrate/analogs & derivatives , Clofibrate/pharmacology , Cyclosporine/pharmacology , Hypolipidemic Agents/pharmacology , Immunosuppressive Agents/pharmacology , Male , Nephrosis/chemically induced , Nephrosis/etiology , Proteinuria/etiology , Proteinuria/prevention & control , Proteinuria/urine , Rats , Rats, Sprague-Dawley , Receptors, Interleukin-2/metabolism
17.
J Atheroscler Thromb ; 3(2): 81-9, 1996.
Article in English | MEDLINE | ID: mdl-9226459

ABSTRACT

The molecular mechanism by which hypolipidemic fibrates and antidiabetic thiazolidinediones exert their hypotriglyceridemic action are discussed. Increased activity of lipoprotein lipase (LPL), a key lipolytic enzyme, and decreased levels of apolipoprotein C-III (apo C-III) seem to explain the hypotriglyceridemic effects of compounds. Both fibrates and thiazolidinediones exert their action by activating transcription factors of the peroxisome proliferator activated receptor (PPAR) family, thereby modulating the expression of the LPL and apo C-II genes. First, treatment of rats with PPAR alpha activators, such as fibrates induced LPL mRNA and activity selectively in the liver. In contrast, the thiazolidinediones, which are high affinity ligands for PPAR gamma, have no effect on liver, but induce LPL mRNA and activity levels in adipose tissue. In hepatocytes, fibrates, unlike the thiazolidinediones, induce LPL mRNA levels, whereas in preadipocyte cell lines the PPAR gamma ligand induces LPL mRNA levels much quicker and to a higher extent than fibrates. Second, apo C-III mRNA and protein production strongly decrease in livers of fibrate but not thiazolidinedione-treated animals. Fibrates also reduced apo C-III production in primary cultures of rat and human hepatocytes. The modulation of the expression of the LPL and apo C-III genes by either PPAR alpha or gamma activators, correlates with the tissue-specific distribution of the respective PPARs: PPAR gamma expression is restricted to adipose tissues, whereas PPAR alpha is expressed predominantly in liver. In both the LPL and apo C-III genes, sequence elements responsible for the modulation of their expression by activated PPARs have been identified which supports that the transcriptional regulation of these genes by fibrates and thiazolidinediones contributes significantly to their hypotriglyceridemic effects in vivo. Whereas thiazolidinediones predominantly affect adipocyte LPL production through activation of PPAR gamma, fibrates exert their effects mainly in the liver via a PPAR alpha-mediated reduction in apo C-III production. This tissue specific transcriptional regulation of genes involved in lipid metabolism by PPAR activators and/or ligands might have important therapeutic implications.


Subject(s)
Clofibrate/analogs & derivatives , Clofibrate/pharmacology , Receptors, Cytoplasmic and Nuclear/drug effects , Thiazoles/pharmacology , Transcription Factors/drug effects , Triglycerides/metabolism , Animals , Humans , Hypertriglyceridemia/drug therapy , Hypertriglyceridemia/prevention & control , Microbodies , Nuclear Proteins , Receptors, Cytoplasmic and Nuclear/metabolism , Transcription Factors/metabolism , Triglycerides/blood
18.
Atherosclerosis ; 117(2): 253-61, 1995 Oct.
Article in English | MEDLINE | ID: mdl-8801871

ABSTRACT

In 17 patients with primary mixed hyperlipidemia we studied levels and composition of lipoproteins in fasting plasma, lipoprotein-modifying enzymes, and postprandial lipoprotein metabolism after an oral fat-tolerance test supplemented with vitamin A before, and 12 weeks after treatment with etophylline clofibrate. With treatment, fasting plasma cholesterol, triglycerides, and the levels of very low density lipoproteins (VLDL), intermediate density lipoproteins (IDL), and low density lipoproteins (LDL) decreased significantly; high density lipoprotein (HDL) cholesterol increased significantly. Treatment caused also an increase in the protein content of IDL, a decrease in the triglyceride content of LDL, and an increase in the size of LDL as assessed by gradient gel electrophoresis. Concentrations of triglycerides, chylomicrons, and chylomicron remnants after an oral fat load supplemented with vitamin A decreased by 33%, 30% and 6%, respectively (P < 0.005; P < 0.01; and P < 0.05). The activity of lipoprotein lipase and hepatic lipase in postheparin plasma increased by 51% and 45%, respectively (P < 0.01; P < 0.05). We found a decrease in the mass concentration of cholesteryl ester transfer protein (P < 0.05). Stepwise multiple regression analysis showed that the triglyceride content of LDL is determined primarily by fasting triglycerides (r = + 0.53, P < 0.05;baseline) and cholesteryl ester transfer protein (r = + 0.49, P < 0.05; 12 weeks); in contrast, the triglyceride content of HDL3 is determined exclusively by accumulation of postprandial triglycerides (r = + 0.67; P < 0.05; baseline) and postprandial chylomicrons (r = +0.87; P < 0.005; 12 weeks). We conclude that hypolipidemic treatment with etophylline clofibrate favorably affects the cardiovascular risk factor profile in primary mixed hyperlipidemia.


Subject(s)
Clofibrate/analogs & derivatives , Glycoproteins , Hyperlipidemias/drug therapy , Hypolipidemic Agents/therapeutic use , Lipoproteins/blood , Carrier Proteins/blood , Cholesterol Ester Transfer Proteins , Chylomicrons/blood , Clofibrate/therapeutic use , Eating , Female , Humans , Hyperlipidemias/blood , Lipase/blood , Lipoprotein(a)/blood , Male , Middle Aged , Transaminases/blood , Triglycerides/blood , Vitamin A/administration & dosage
19.
Vnitr Lek ; 41(10): 677-81, 1995 Oct.
Article in Slovak | MEDLINE | ID: mdl-8578698

ABSTRACT

The objective was to investigate the tolerance of ethophylline clofibrate (EPC) and its effectiveness on changes of dyslipidaemia and compensation of diabetes in type II diabetics during six-month administration of the preparation Duolip forte (Merckle). Twenty diabetics with dyslipoproteinaemia IIb and IV according to Frederickson's classification, compensated by diet alone or combined with oral antidiabetics (Glucobene, Merckle) were included in the study consecutively according to uniform basal criteria. The selected hypolipidaemic agent was administered to patients according to the following pattern: the first four weeks 1,000 mg (2 tablets in the evening) the next two weeks 1.5 tablets and then till the end of the investigation 1 tablet in the evening. In all patients treatment with EPC led to a significant reduction of the total cholesterol level (CH) at all time intervals. Changes of ApoB, ApoA1 and Lp(a) serum levels did not attain statistical significance but trends were revealed (e.g. a drop of the ApoB/ApoA1 index) which are consistent with the expected favourable action of EPC on the CH distribution in lipoproteins. The triacylglycerol (TG) serum concentration declined significantly already after one month of treatment and after identification of five patients whose TG were distributed in separate clusters the hypotriacylglycerolaemic effect of EPC persisted still three months after treatment. It may be summarized that treatment of dyslipoproteinaemia of the type II diabetics with ethophylline clofibrate (Duolip forte, Merckle) led a) to a marked reduction (13-15%) of serum cholesterol, which b) diminished (to 8-9%) but persisted still after 6 months of treatment, c) the greatest effect of EPC on the TG serum level was observed one month after treatment, d) all improvements of lipid parameters occurred without affecting the compensation of diabetes, or BMI and were not associated with any side-effects of EPC.


Subject(s)
Clofibrate/analogs & derivatives , Diabetes Mellitus, Type 2/complications , Hyperlipoproteinemia Type II/drug therapy , Hyperlipoproteinemia Type IV/drug therapy , Hypolipidemic Agents/therapeutic use , Clofibrate/therapeutic use , Female , Humans , Hyperlipoproteinemia Type II/complications , Hyperlipoproteinemia Type IV/complications , Male , Middle Aged
20.
Vnitr Lek ; 41(4): 240-2, 1995 Apr.
Article in Slovak | MEDLINE | ID: mdl-7762188

ABSTRACT

The authors investigated the effect of the hypolipaemic agent ethophylline clofibrate (Duolip forte) on some parameters of the lipid and carbohydrate metabolism in patients with combined familial hyperlipoproteinaemia. They administered the pharmaceutic to 12 patients-500 mg for a period of 3 months. As to biochemical parameters they assessed the total cholesterol, triglyceride, HDL-cholesterol, apo-B, apo-A-I; blood glucose and IRI levels using the glucose tolerance test following the dose of 75 g glucose. The patients were checked on and three months after the onset of treatment. During treatment a significant drop of the apo-B level occurred (1.34 +/- 0.12, 1.20 +/- 0.15 g/l, p < 0.05) and of the fasting blood glucose level (5.7 +/- 0.62, 5.0 +/- 0.34 mmol/l, p < 0.005), whereby the blood sugar and IRI levels after the glucose load did not change significantly. The authors did not record a significant effect on the total cholesterol, triglyceride and HDL-cholesterol levels. The results of the investigation indicate that Duolip forte is a pharmaceutic which can exert a favourable effect on the apo-B level and the blood glucose level during combined hypolipaemic and/or antidiabetic treatment.


Subject(s)
Clofibrate/analogs & derivatives , Hyperlipidemia, Familial Combined/drug therapy , Hypolipidemic Agents/therapeutic use , Apolipoproteins B/blood , Blood Glucose/analysis , Clofibrate/therapeutic use , Female , Humans , Hyperlipidemia, Familial Combined/blood , Male
SELECTION OF CITATIONS
SEARCH DETAIL