1. To compare the effectiveness of different drug forms of silymarin: standardized extract of silymarin (SS), micronized silymarin (MS) and silymarin in the form of phytosome (PS) on dyslipidemia and liver fat accumulation in a model of metabolic syndrome, in non-obese hereditary hypertriglyceridemic rats. The second aim of this study was to slightly uncover the silymarin action on enzymes and proteins involved in cholesterol metabolism and excretion. 2. Silymarin administered to hereditary hypertriglyceridemic rats as dietary supplements (1%) for 4 weeks significantly lowered the plasma levels of triglycerides, total cholesterol and markedly increased HDL cholesterol level. Western blot analyses showed significant increase in the protein expression of CYP7A1 and CYP4A and increase in protein expression of selected ABC transporters. Silymarin in the form of phytosome and micronized silymarin were more effective forms of silymarin. 3. These findings suggest that silymarin may favorably affect the metabolism of cholesterol and triglycerides in rats with metabolic syndrome. Raising HDL levels suggests potentially important anti-atherogenic effect of silymarin. The changes in expression of cytochromes P450 and ABC transporters involved in cholesterol metabolism and excretion could be partially responsible for the hypolipidemic effect of silymarin.

• MeSH
• ABC transportéry metabolismus   MeSH
• biologická dostupnost MeSH
• cholesterol-7-alfa-hydroxylasa metabolismus   MeSH
• cytochrom P450 CYP4A metabolismus   MeSH
• dyslipidemie krev   komplikace   farmakoterapie   MeSH
• játra účinky léků   enzymologie   MeSH
• lipidy krev   MeSH
• metabolický syndrom krev   komplikace   farmakoterapie   MeSH
• potkani Wistar MeSH
• silymarin farmakologie   terapeutické užití   MeSH
• western blotting MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• cytochrom P450 CYP4A analýza   genetika   účinky léků   MeSH
• dieta metody   statistika a číselné údaje   využití   MeSH
• experimenty na zvířatech MeSH
• exprese genu genetika   účinky léků   MeSH
• financování organizované MeSH
• fluorbenzeny aplikace a dávkování   farmakologie   terapeutické užití   MeSH
• hypolipidemika aplikace a dávkování   farmakologie   terapeutické užití   MeSH
• krysa rodu rattus MeSH
• metabolismus lipidů účinky léků   MeSH
• pyrimidiny aplikace a dávkování   farmakokinetika   terapeutické užití   MeSH
• sulfonamidy aplikace a dávkování   farmakologie   terapeutické užití   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• zvířata MeSH

BACKGROUND: Malignant hypertension is a life-threatening condition, and its pathophysiology is still poorly understood. The present study was designed to evaluate the role of interaction of the renin-angiotensin system with 20-hydroxyeicosatetraenoic acid (20-HETE), a product of cytochrome P450 (CYP)-dependent ω-hydroxylase pathway, in the pathophysiology of angiotensin II (ANG II)-dependent malignant hypertension in Cyp1a1-Ren-2 transgenic rats. METHODS: Malignant hypertension was induced by 12 days׳ dietary administration of 0.3 % indole-3-carbinol (I3C), a natural xenobiotic that activates a mouse renin gene. We hypothesized that chronic administration of fenofibrate, 190mg/kg body weight, a lipid-lowering drug, should increase renal production of 20-HETE, a tubular transport inhibitor; an expected increase in sodium excretion would oppose the development of ANG II-dependent malignant hypertension. Blood pressure was monitored by radiotelemetry, and at the end of the experiment rats were prepared for renal functional studies to evaluate in vivo the pressure-natriuresis relationship in response to stepwise reductions in renal arterial pressure (RAP). RESULTS: In I3C-induced rats, the treatment with fenofibrate significantly attenuated hypertension and improved the slope of the pressure-natriuresis relationship. Although fenofibrate treatment increased kidney gene and protein expression of CYP4A1, a major isoform responsible for 20-HETE formation, it did not increase renal 20-HETE concentration. On the contrary, fenofibrate treatment significantly suppressed renin gene expression, plasma renin activity and plasma and kidney ANG II levels. CONCLUSIONS: Fenofibrate treatment significantly attenuated the course of malignant hypertension in I3C-induced CYP1a1-Ren-2 transgenic rats, and the mechanism responsible for antihypertensive action was fenofibrate-induced suppression of renin-angiotensin system activity.

• MeSH
• aktivace transkripce MeSH
• cytochrom P-450 CYP1A1 genetika   MeSH
• cytochrom P450 CYP4A metabolismus   MeSH
• fenofibrát farmakologie   terapeutické užití   MeSH
• hodnoty glomerulární filtrace účinky léků   MeSH
• homeostáza účinky léků   MeSH
• hypertenze maligní chemicky indukované   farmakoterapie   MeSH
• indoly MeSH
• krevní tlak MeSH
• kyseliny hydroxyeikosatetraenové metabolismus   MeSH
• ledviny metabolismus   MeSH
• natriuréza účinky léků   MeSH
• potkani transgenní MeSH
• renální oběh účinky léků   MeSH
• renin-angiotensin systém účinky léků   MeSH
• renin genetika   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

The aim of the present study was to evaluate the effects of inhibition of cytochrome P-450 (CYP) activity by 1-aminobenzotriazole (ABT) and by CoCl(2), first, on the development of hypertension when treatment was started in young male heterozygous Ren-2 transgenic rats (TGR) and, second, on blood pressure (BP) when treatment was started in adult TGR with established hypertension. Normotensive Hannover Sprague-Dawley (HanSD) rats served as controls. In addition, the renal cortical activities of omega-hydroxylase, the enzyme catalyzing the formation of 20-hydroxyeicosatetraenoic acid (20-HETE), and of epoxygenase, the enzyme responsible for epoxyeicosatrienoic acids (EETs) production, and urinary excretion of 20-HETE and EETs in TGR and HanSD rats were assessed. TGR have higher renal tissue omega-hydroxylase activity and urinary excretion of 20-HETE but have significantly lower renal epoxygenase activity and urinary excretion of EETs than HanSD rats. Treatment of young TGR with ABT and CoCl(2) attenuated the development of hypertension and cardiac hypertrophy and prevented glomerulosclerosis. Administration of ABT and CoCl(2) in adult TGR decreased BP, cardiac hypertrophy, but did not reduce glomerulosclerosis. Our data suggest that altered production and/or action of CYP-derived metabolites play a permissive role in the development and maintenance of hypertension in TGR by enhancing ANG II-induced vasoconstriction.

• MeSH
• cytochrom P450 CYP4A metabolismus   MeSH
• financování organizované MeSH
• fokálně segmentální glomeruloskleróza patofyziologie   MeSH
• heterozygot MeSH
• hypertenze patofyziologie   MeSH
• inhibitory cytochromu P450 MeSH
• inhibitory enzymů farmakologie   MeSH
• kardiomegalie patofyziologie   MeSH
• kobalt MeSH
• krevní tlak účinky léků   MeSH
• krysa rodu rattus MeSH
• kůra ledviny MeSH
• kyseliny hydroxyeikosatetraenové biosyntéza   MeSH
• modely nemocí na zvířatech MeSH
• náhodné rozdělení MeSH
• oxygenasy metabolismus   MeSH
• potkani Sprague-Dawley MeSH
• renin-angiotensin systém fyziologie   MeSH
• renin genetika   metabolismus   MeSH
• systém (enzymů) cytochromů P-450 metabolismus   MeSH
• triazoly farmakologie   MeSH
• vazokonstrikce MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH

BACKGROUND: The present study was performed in hypertensive Ren-2 transgenic rats (TGR) and in normotensive Hannover Sprague-Dawley (HanSD) rats. First, the intrarenal protein expression of CYP4A, the enzyme catalyzing the formation of 20-hydroxyeicosatetraenoic acid (20-HETE), and of CYP2C23, the enzyme responsible for epoxyeicosatrienoic acid (EET) production, was evaluated. Second, the renal functional responses to inhibition of the intrarenal formation of 20-HETE and EETs were investigated. METHODS: Renal hemodynamics and electrolyte excretion were evaluated in response to the administration of inhibitors of 20-HETE and EET formation into the renal artery. In renal cortical tissue, CYP4A and CYP2C23 protein expression was assessed by Western blot analysis. Urinary concentrations of 20-HETE and EETs were measured using a fluorescent HPLC assay. RESULTS: TGR have higher kidney CYP4A protein expression and urinary 20-HETE excretion but significantly lower CYP2C23 protein expression and urinary EET excretion than HanSD. Intrarenal inhibition of 20-HETE and EET formation decreased sodium excretion in HanSD, whereas inhibition of 20-HETE increased urinary excretion of sodium in TGR without altering renal hemodynamics. CONCLUSIONS: Our data suggest that in TGR, deficient intrarenal synthesis of EETs combined with increased synthesis of 20-HETE with its stimulation of tubular sodium absorption may contribute to the development of hypertension in TGR. 2007 S. Karger AG, Basel

• MeSH
• financování organizované MeSH
• geneticky modifikovaná zvířata MeSH
• hypertenze genetika   patofyziologie   MeSH
• krevní tlak genetika   MeSH
• krysa rodu rattus MeSH
• kyseliny arachidonové fyziologie   MeSH
• kyseliny hydroxyeikosatetraenové fyziologie   MeSH
• ledviny fyziologie   MeSH
• potkani Sprague-Dawley MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• srovnávací studie MeSH

Silymarin is widely used in supportive therapy of liver diseases. It has been shown lately that silymarin has beneficial effects on some risk factors of atherosclerosis owing to its hypolipidemic properties. PPARalpha plays a key role in lipid metabolism and homeostasis as its target genes are involved in catabolism of fatty acids by beta-oxidation (e.g. acyl-CoA oxidase) and by omega-oxidation (e.g. cytochrome P4504A). Here we studied the possibility that hypolipidemic effects of silymarin may be mediated by PPARalpha. Rats fed with a high-cholesterol diet with either silymarin or fenofibrate (as a positive control both for PPARalpha expression as well as for lipid determination) were used. The effects of silymarin on expression of PPARalpha both at the mRNA (including selected target genes) as well as the protein level were determined. In parallel, the levels of cholesterol and triacylglycerols were determined. Our results confirmed the hypolipidemic effects of silymarin and demonstrated that these effects are probably not mediated by PPARalpha because of unchanged mRNA levels of PPARalpha target genes. Furthermore, this work shows for the first time that cholesterol itself inhibits expression of CYP4A mRNA.

• MeSH
• exprese genu účinky léků   MeSH
• financování organizované MeSH
• hypolipidemika farmakologie   metabolismus   MeSH
• krysa rodu rattus MeSH
• potkani Wistar MeSH
• PPAR alfa biosyntéza   fyziologie   genetika   MeSH
• silymarin fyziologie   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH

Recent studies suggest that treatment with SGLT-2 inhibitors can reduce hepatic lipid storage and ameliorate non-alcoholic fatty liver disease (NAFLD) development beyond their glycemic benefits. However, the exact mechanism involved is still unclear. We investigated the hepatic metabolic effect of empagliflozin (10 mg/kg/day for eight weeks) on the development of NAFLD and its complications using HHTg rats as a non-obese prediabetic rat model. Empagliflozin treatment reduced neutral triacylglycerols and lipotoxic diacylglycerols in the liver and was accompanied by significant changes in relative mRNA expression of lipogenic enzymes (Scd-1, Fas) and transcription factors (Srebp1, Pparγ). In addition, alterations in the gene expression of cytochrome P450 proteins, particularly Cyp2e1 and Cyp4a, together with increased Nrf2, contributed to the improvement of hepatic lipid metabolism after empagliflozin administration. Decreased circulating levels of fetuin-A improved lipid metabolism and attenuated insulin resistance in the liver and in peripheral tissues. Our results highlight the beneficial effect of empagliflozin on hepatic lipid metabolism and lipid accumulation independent of obesity, with the mechanisms understood to involve decreased lipogenesis, alterations in cytochrome P450 proteins, and decreased fetuin-A. These changes help to alleviate NAFLD symptoms in the early phase of the disease and before the onset of diabetes.

• MeSH
• benzhydrylové sloučeniny farmakologie   MeSH
• glifloziny farmakologie   MeSH
• glukosidy farmakologie   MeSH
• hyperglykemie farmakoterapie   etiologie   metabolismus   MeSH
• hyperlipoproteinemie typ IV komplikace   farmakoterapie   metabolismus   MeSH
• inzulinová rezistence MeSH
• játra účinky léků   metabolismus   MeSH
• krysa rodu rattus MeSH
• mediátory zánětu metabolismus   MeSH
• metabolismus lipidů účinky léků   MeSH
• modely nemocí na zvířatech MeSH
• mutantní kmeny potkanů MeSH
• nealkoholová steatóza jater etiologie   metabolismus   prevence a kontrola   MeSH
• obezita komplikace   metabolismus   MeSH
• oxidační stres účinky léků   MeSH
• potkani Wistar MeSH
• prediabetes komplikace   farmakoterapie   metabolismus   MeSH
• progrese nemoci MeSH
• systém (enzymů) cytochromů P-450 metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Parenteral nutrition (PN) is often associated with the deterioration of liver functions (PNALD). Omega-3 polyunsaturated fatty acids (PUFA) were reported to alleviate PNALD but the underlying mechanisms have not been fully unraveled yet. Using omics´ approach, we determined serum and liver lipidome, liver proteome, and liver bile acid profile as well as markers of inflammation and oxidative stress in rats administered either ω-6 PUFA based lipid emulsion (Intralipid) or ω-6/ω-3 PUFA blend (Intralipid/Omegaven) via the enteral or parenteral route. In general, we found that enteral administration of both lipid emulsions has less impact on the liver than the parenteral route. Compared with parenterally administered Intralipid, PN administration of ω-3 PUFA was associated with 1. increased content of eicosapentaenoic (EPA)- and docosahexaenoic (DHA) acids-containing lipid species; 2. higher abundance of CYP4A isoenzymes capable of bioactive lipid synthesis and the increased content of their potential products (oxidized EPA and DHA); 3. downregulation of enzymes involved CYP450 drug metabolism what may represent an adaptive mechanism counteracting the potential negative effects (enhanced ROS production) of PUFA metabolism; 4. normalized anti-oxidative capacity and 5. physiological BAs spectrum. All these findings may contribute to the explanation of ω-3 PUFA protective effects in the context of PN.

• MeSH
• emulze MeSH
• enterální výživa metody   MeSH
• fosfolipidy MeSH
• játra metabolismus   MeSH
• krysa rodu rattus MeSH
• kyselina eikosapentaenová chemie   MeSH
• kyseliny dokosahexaenové chemie   MeSH
• kyslík metabolismus   MeSH
• lipidomika MeSH
• lipidy chemie   MeSH
• malondialdehyd metabolismus   MeSH
• metabolomika MeSH
• nenasycené mastné kyseliny metabolismus   MeSH
• omega-3 mastné kyseliny chemie   MeSH
• oxidační stres MeSH
• parenterální výživa metody   MeSH
• potkani Wistar MeSH
• proteom metabolismus   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• rybí oleje MeSH
• sójový olej MeSH
• zánět MeSH
• žlučové kyseliny a soli analýza   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH

The combination of plant-derived compounds with anti-diabetic agents to manage hepatic steatosis closely associated with diabetes mellitus may be a new therapeutic approach. Silymarin, a complex of bioactive substances extracted from Silybum marianum, evinces an antioxidative, anti-inflammatory, and hepatoprotective activity. In this study, we investigated whether metformin (300 mg/kg/day for four weeks) supplemented with micronized silymarin (600 mg/kg/day) would be effective in mitigating fatty liver disturbances in a pre-diabetic model with dyslipidemia. Compared with metformin monotherapy, the metformin-silymarin combination reduced the content of neutral lipids (TAGs) and lipotoxic intermediates (DAGs). Hepatic gene expression of enzymes and transcription factors involved in lipogenesis (Scd-1, Srebp1, Pparγ, and Nr1h) and fatty acid oxidation (Pparα) were positively affected, with hepatic lipid accumulation reducing as a result. Combination therapy also positively influenced arachidonic acid metabolism, including its metabolites (14,15-EET and 20-HETE), mitigating inflammation and oxidative stress. Changes in the gene expression of cytochrome P450 enzymes, particularly Cyp4A, can improve hepatic lipid metabolism and moderate inflammation. All these effects play a significant role in ameliorating insulin resistance, a principal background of liver steatosis closely linked to T2DM. The additive effect of silymarin in metformin therapy can mitigate fatty liver development in the pre-diabetic state and before the onset of diabetes.

• Publikační typ
• časopisecké články MeSH

Ovarian hormone deficiency leads to increased body weight, visceral adiposity, fatty liver and disorders associated with menopausal metabolic syndrome. To better understand the underlying mechanisms of these disorders in their early phases of development, we investigated the effect of ovariectomy on lipid and glucose metabolism. Compared to sham-operated controls, ovariectomized Wistar female rats markedly increased whole body and visceral adipose tissue weight (p ˂ 0.05) and exhibited insulin resistance in peripheral tissues. Severe hepatic triglyceride accumulation (p ˂ 0.001) after ovariectomy preceded changes in both serum lipids and glucose intolerance, reflecting alterations in some CYP proteins. Increased CYP2E1 (p ˂ 0.05) and decreased CYP4A (p ˂ 0.001) after ovariectomy reduced fatty acid oxidation and induced hepatic steatosis. Decreased triglyceride metabolism and secretion from the liver contributed to hepatic triglyceride accumulation in response to ovariectomy. In addition, interscapular brown adipose tissue of ovariectomized rats exhibited decreased fatty acid oxidation (p ˂ 0.01), lipogenesis (p ˂ 0.05) and lipolysis (p ˂ 0.05) despite an increase in tissue weight. The results provide evidence that impaired hepatic triglycerides and dysregulation of some CYP450 proteins may have been involved in the development of hepatic steatosis. The low metabolic activity of brown adipose tissue may have contributed to visceral adiposity as well as triglyceride accumulation during the postmenopausal period.

• MeSH
• bílá tuková tkáň metabolismus   MeSH
• dieta s vysokým obsahem tuků MeSH
• dyslipidemie metabolismus   MeSH
• glukosa metabolismus   MeSH
• hmotnostní přírůstek MeSH
• hnědá tuková tkáň metabolismus   MeSH
• inzulin metabolismus   MeSH
• inzulinová rezistence MeSH
• játra metabolismus   MeSH
• krysa rodu rattus MeSH
• lipidy krev   MeSH
• lipogeneze účinky léků   MeSH
• lipolýza MeSH
• menopauza metabolismus   fyziologie   MeSH
• metabolismus lipidů účinky léků   fyziologie   MeSH
• nitrobřišní tuk metabolismus   MeSH
• obezita metabolismus   MeSH
• ovarektomie škodlivé účinky   MeSH
• poruchy metabolismu lipidů etiologie   patofyziologie   MeSH
• postmenopauza metabolismus   fyziologie   MeSH
• potkani Wistar MeSH
• systém (enzymů) cytochromů P-450 metabolismus   fyziologie   MeSH
• triglyceridy metabolismus   MeSH
• ztučnělá játra metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH