While phosphodiesterase-5 inhibition (PED5i) may prevent hypertrophy and failure in pressure-overloaded heart in an experimental model, the impact of PDE5i on volume-overload (VO)-induced hypertrophy is unknown. It is also unclear whether the hypertrophied right ventricle (RV) and left ventricle (LV) differ in their responsiveness to long-term PDE5i and if this therapy affects renal function. The goal of this study was to elucidate the effect of PDE5i treatment in VO due to aorto-caval fistula (ACF) and to compare PDE5i treatment with standard heart failure (HF) therapy with angiotensin-converting enzyme inhibitor (ACEi). ACF/sham procedure was performed on male HanSD rats aged 8 weeks. ACF animals were randomized for PDE5i sildenafil, ACEi trandolapril, or placebo treatments. After 20 weeks, RV and LV function (echocardiography, pressure-volume analysis), myocardial gene expression, and renal function were studied. Separate rat cohorts served for survival analysis. ACF led to biventricular eccentric hypertrophy (LV: +68%, RV: +145%), increased stroke work (LV: 3.6-fold, RV: 6.7-fold), and reduced load-independent systolic function (PRSW, LV: -54%, RV: -51%). Both ACF ventricles exhibited upregulation of the genes of myocardial stress and glucose metabolism. ACEi but not PDE5i attenuated pulmonary congestion, LV remodeling, albuminuria, and improved survival (median survival in ACF/ACEi was 41 weeks vs. 35 weeks in ACF/placebo, p = .02). PDE5i increased cyclic guanosine monophosphate levels in the lungs, but not in the RV, LV, or kidney. PDE5i did not improve survival rate and cardiac and renal function in ACF rats, in contrast to ACEi. VO-induced HF is not responsive to PDE5i therapy.

• Klíčová slova
• heart failure, phosphodiesterase-5 inhibition, rats, right ventricle, volume overload,
• MeSH
• inhibitory ACE * farmakologie   MeSH
• inhibitory fosfodiesterasy 5 * farmakologie   MeSH
• kardiomegalie farmakoterapie   MeSH
• krysa rodu Rattus MeSH
• remodelace komor * MeSH
• srdeční selhání * farmakoterapie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• inhibitory ACE * MeSH
• inhibitory fosfodiesterasy 5 * MeSH

An association between congestive heart failure (CHF) and chronic kidney disease (CKD) results in extremely poor patient survival rates. Previous studies have shown that increasing kidney epoxyeicosatrienoic acids (EETs) by blocking soluble epoxide hydrolase (sEH), an enzyme responsible for EETs degradation, improves the survival rate in CHF induced by aorto-caval fistula (ACF) and attenuates CKD progression. This prompted us to examine if sEH inhibitor treatment would improve the outcome if both experimental conditions are combined. Fawn-hooded hypertensive (FHH) rats, a genetic model showing early CKD development was employed, and CHF was induced by ACF. Treatment with an sEH inhibitor was initiated 4 weeks after ACF creation, in FHH and in fawn-hooded low-pressure (FHL) rats, a control strain without renal damage. The follow-up period was 20 weeks. We found that ACF FHH rats exhibited substantially lower survival rates (all the animals died by week 14) as compared with the 64% survival rate observed in ACF FHL rats. The former group showed pronounced albuminuria (almost 30-fold higher than in FHL) and reduced intrarenal EET concentrations. The sEH inhibitor treatment improved survival rate and distinctly reduced increases in albuminuria in ACF FHH and in ACF FHL rats, however, all the beneficial actions were more pronounced in the hypertensive strain. These data indicate that pharmacological blockade of sEH could be a novel therapeutic approach for the treatment of CHF, particularly under conditions when it is associated with CKD.

• Klíčová slova
• chronic kidney disease, congestive heart failure, hypertension, renin-angiotensin-aldosterone system, soluble epoxide hydrolase inhibitor,
• Publikační typ
• časopisecké články MeSH

We showed recently that increasing kidney epoxyeicosatrienoic acids (EETs) by blocking soluble epoxide hydrolase (sEH), an enzyme responsible for EETs degradation, retarded the development of renal dysfunction and progression of aorto-caval fistula(ACF)-induced congestive heart failure (CHF) in Ren-2 transgenic hypertensive rats (TGR). In that study the final survival rate of untreated ACF TGR was only 14 % but increased to 41 % after sEH blockade. Here we examined if sEH inhibition added to renin-angiotensin system (RAS) blockade would further enhance protection against ACF-induced CHF in TGR. The treatment regimens were started one week after ACF creation and the follow-up period was 50 weeks. RAS was blocked using angiotensin-converting enzyme inhibitor (ACEi, trandolapril, 6 mg/l) and sEH with an sEH inhibitor (sEHi, c-AUCB, 3 mg/l). Renal hemodynamics and excretory function were determined two weeks post-ACF, just before the onset of decompensated phase of CHF. 29 weeks post-ACF no untreated animal survived. ACEi treatment greatly improved the survival rate, to 84 % at the end of study. Surprisingly, combined treatment with ACEi and sEHi worsened the rate (53 %). Untreated ACF TGR exhibited marked impairment of renal function and the treatment with ACEi alone or combined with sEH inhibition did not prevent it. In conclusion, addition of sEHi to ACEi treatment does not provide better protection against CHF progression and does not increase the survival rate in ACF TGR: indeed, the rate decreases significantly. Thus, combined treatment with sEHi and ACEi is not a promising approach to further attenuate renal dysfunction and retard progression of CHF.

• MeSH
• arteriovenózní píštěl MeSH
• benzoáty farmakologie   terapeutické užití   MeSH
• epoxid hydrolasy antagonisté a inhibitory   MeSH
• indoly terapeutické užití   MeSH
• inhibitory ACE terapeutické užití   MeSH
• kombinovaná farmakoterapie MeSH
• krysa rodu Rattus MeSH
• močovina analogy a deriváty   farmakologie   terapeutické užití   MeSH
• potkani Sprague-Dawley MeSH
• potkani transgenní MeSH
• preklinické hodnocení léčiv MeSH
• renální insuficience etiologie   prevence a kontrola   MeSH
• srdeční selhání komplikace   farmakoterapie   mortalita   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• 4-(4-(3-adamantan-1-ylureido)cyclohexyloxy)benzoic acid MeSH Prohlížeč
• benzoáty MeSH
• epoxid hydrolasy MeSH
• indoly MeSH
• inhibitory ACE MeSH
• močovina MeSH
• trandolapril MeSH Prohlížeč

Metformin is widely prescribed as a first-choice antihyperglycemic drug for treatment of type 2 diabetes mellitus, and recent epidemiological studies showed its utility also in cancer therapy. Although it is in use since the 1970s, its molecular target, either for antihyperglycemic or antineoplastic action, remains elusive. However, the body of the research on metformin effect oscillates around mitochondrial metabolism, including the function of oxidative phosphorylation (OXPHOS) apparatus. In this study, we focused on direct inhibitory mechanism of biguanides (metformin and phenformin) on OXPHOS complexes and its functional impact, using the model of isolated brown adipose tissue mitochondria. We demonstrate that biguanides nonspecifically target the activities of all respiratory chain dehydrogenases (mitochondrial NADH, succinate, and glycerophosphate dehydrogenases), but only at very high concentrations (10-2-10-1 M) that highly exceed cellular concentrations observed during the treatment. In addition, these concentrations of biguanides also trigger burst of reactive oxygen species production which, in combination with pleiotropic OXPHOS inhibition, can be toxic for the organism. We conclude that the beneficial effect of biguanides should probably be associated with subtler mechanism, different from the generalized inhibition of the respiratory chain.

• MeSH
• biguanidy farmakologie   MeSH
• fenformin farmakologie   MeSH
• glycerolfosfátdehydrogenasa metabolismus   MeSH
• hnědá tuková tkáň cytologie   MeSH
• hypoglykemika farmakologie   MeSH
• krysa rodu Rattus MeSH
• kyselina jantarová metabolismus   MeSH
• membránový potenciál mitochondrií účinky léků   MeSH
• metformin farmakologie   MeSH
• mitochondrie účinky léků   metabolismus   MeSH
• oxidace-redukce účinky léků   MeSH
• peroxid vodíku farmakologie   MeSH
• potkani Wistar MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• biguanidy MeSH
• fenformin MeSH
• glycerolfosfátdehydrogenasa MeSH
• hypoglykemika MeSH
• kyselina jantarová MeSH
• metformin MeSH
• peroxid vodíku MeSH
• reaktivní formy kyslíku MeSH

Volume overload leads to development of eccentric cardiac hypertrophy and heart failure. In our previous report, we have shown myocyte hypertrophy with no fibrosis and decrease in gap junctional coupling via connexin43 in a rat model of aorto-caval fistula at 21 weeks. Here we set to analyze the electrophysiological and protein expression changes in the left ventricle and correlate them with phenotypic severity based upon ventricles to body weight ratio. ECG analysis showed increased amplitude and duration of the P wave, prolongation of PR and QRS interval, ST segment elevation and decreased T wave amplitude in the fistula group. Optical mapping showed a prolongation of action potential duration in the hypertrophied hearts. Minimal conduction velocity (CV) showed a bell-shaped curve, with a significant increase in the mild cases and there was a negative correlation of both minimal and maximal CV with heart to body weight ratio. Since the CV is influenced by gap junctional coupling as well as the autonomic nervous system, we measured the amounts of tyrosine hydroxylase (TH) and choline acetyl transferase (ChAT) as a proxy for sympathetic and parasympathetic innervation, respectively. At the protein level, we confirmed a significant decrease in total and phosphorylated connexin43 that was proportional to the level of hypertrophy, and similarly decreased levels of TH and ChAT. Even at a single time-point, severity of morphological phenotype correlates with progression of molecular and electrophysiological changes, with the most hypertrophied hearts showing the most severe changes that might be related to arrhythmogenesis.

• Klíčová slova
• aorto-caval fistula, autonomic heart innervation, conduction velocity, connexin43, hypertrophy,
• Publikační typ
• časopisecké články MeSH

Inflammation and oxidative and dicarbonyl stress play important roles in the pathogenesis of type 2 diabetes. Metformin is the first-line drug of choice for the treatment of type 2 diabetes because it effectively suppresses gluconeogenesis in the liver. However, its "pleiotropic" effects remain controversial. In the current study, we tested the effects of metformin on inflammation, oxidative and dicarbonyl stress in an animal model of inflammation and metabolic syndrome, using spontaneously hypertensive rats that transgenically express human C-reactive protein (SHR-CRP). We treated 8-month-old male transgenic SHR-CRP rats with metformin (5 mg/kg/day) mixed as part of a standard diet for 4 weeks. A corresponding untreated control group of male transgenic SHR-CRP rats were fed a standard diet without metformin. In a similar fashion, we studied a group of nontransgenic SHR treated with metformin and an untreated group of nontransgenic SHR controls. In each group, we studied 6 animals. Parameters of glucose and lipid metabolism and oxidative and dicarbonyl stress were measured using standard methods. Gene expression profiles were determined using Affymetrix GeneChip Arrays. Statistical significance was evaluated by two-way ANOVA. In the SHR-CRP transgenic strain, we found that metformin treatment decreased circulating levels of inflammatory response marker IL-6, TNFα and MCP-1 while levels of human CRP remained unchanged. Metformin significantly reduced oxidative stress (levels of conjugated dienes and TBARS) and dicarbonyl stress (levels of methylglyoxal) in left ventricles, but not in kidneys. No significant effects of metformin on oxidative and dicarbonyl stress were observed in SHR controls. In addition, metformin treatment reduced adipose tissue lipolysis associated with human CRP. Possible molecular mechanisms of metformin action-studied by gene expression profiling in the liver-revealed deregulated genes from inflammatory and insulin signaling, AMP-activated protein kinase (AMPK) signaling and gluconeogenesis pathways. It can be concluded that in the presence of high levels of human CRP, metformin protects against inflammation and oxidative and dicarbonyl stress in the heart, but not in the kidney. Accordingly, these cardioprotective effects of metformin might be especially effective in diabetic patients with high levels of CRP.

• MeSH
• C-reaktivní protein biosyntéza   genetika   MeSH
• cytokiny metabolismus   MeSH
• exprese genu MeSH
• glukosa metabolismus   MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• lipolýza účinky léků   genetika   MeSH
• metformin farmakologie   MeSH
• myokard metabolismus   MeSH
• oxidační stres účinky léků   genetika   MeSH
• potkani inbrední SHR MeSH
• potkani transgenní MeSH
• proteinkinasy aktivované AMP genetika   metabolismus   MeSH
• pyruvaldehyd metabolismus   MeSH
• srdeční komory metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• C-reaktivní protein MeSH
• cytokiny MeSH
• glukosa MeSH
• metformin MeSH
• proteinkinasy aktivované AMP MeSH
• pyruvaldehyd MeSH

The detailed mechanisms determining the course of congestive heart failure (CHF) and associated renal dysfunction remain unclear. In a volume overload model of CHF induced by creation of aorto-caval fistula (ACF) in Hannover Sprague-Dawley (HanSD) rats we explored the putative pathogenetic contribution of epoxyeicosatrienoic acids (EETs), active products of CYP-450 dependent epoxygenase pathway of arachidonic acid metabolism, and compared it with the role of the renin-angiotensin system (RAS). Chronic treatment with cis-4-[4-(3-adamantan-1-yl-ureido) cyclohexyloxy]benzoic acid (c-AUCB, 3 mg/l in drinking water), an inhibitor of soluble epoxide hydrolase (sEH) which normally degrades EETs, increased intrarenal and myocardial EETs to levels observed in sham-operated HanSD rats, but did not improve the survival or renal function impairment. In contrast, chronic angiotensin-converting enzyme inhibition (ACEi, trandolapril, 6 mg/l in drinking water) increased renal blood flow, fractional sodium excretion and markedly improved survival, without affecting left ventricular structure and performance. Hence, renal dysfunction rather than cardiac remodeling determines long-term mortality in advanced stage of CHF due to volume overload. Strong protective actions of ACEi were associated with suppression of the vasoconstrictor/sodium retaining axis and activation of vasodilatory/natriuretic axis of the renin-angiotensin system in the circulating blood and kidney tissue.

• MeSH
• angiotensin I krev   MeSH
• angiotensin II krev   MeSH
• benzoáty farmakologie   terapeutické užití   MeSH
• epoxid hydrolasy antagonisté a inhibitory   MeSH
• epoxidové sloučeniny metabolismus   MeSH
• inhibitory ACE MeSH
• krysa rodu Rattus MeSH
• kyselina 8,11,14-eikosatrienová analogy a deriváty   krev   metabolismus   MeSH
• ledviny metabolismus   MeSH
• močovina analogy a deriváty   farmakologie   terapeutické užití   MeSH
• modely nemocí na zvířatech MeSH
• myokard metabolismus   MeSH
• náhodné rozdělení MeSH
• peptidové fragmenty krev   MeSH
• preklinické hodnocení léčiv MeSH
• renální insuficience krev   etiologie   prevence a kontrola   MeSH
• renin-angiotensin systém účinky léků   MeSH
• srdeční selhání krev   komplikace   diagnostické zobrazování   farmakoterapie   MeSH
• ultrasonografie MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• 4-(4-(3-adamantan-1-ylureido)cyclohexyloxy)benzoic acid MeSH Prohlížeč
• angiotensin I (1-7) MeSH Prohlížeč
• angiotensin I MeSH
• angiotensin II MeSH
• benzoáty MeSH
• epoxid hydrolasy MeSH
• epoxidové sloučeniny MeSH
• inhibitory ACE MeSH
• kyselina 8,11,14-eikosatrienová MeSH
• močovina MeSH
• peptidové fragmenty MeSH

Inflammation and oxidative stress have been implicated in the pathogenesis of metabolic disturbances. Esters of fumaric acid, mainly dimethyl fumarate, exhibit immunomodulatory, anti-inflammatory, and anti-oxidative effects. In the current study, we tested the hypothesis that fumaric acid ester (FAE) treatment of an animal model of inflammation and metabolic syndrome, the spontaneously hypertensive rat transgenically expressing human C-reactive protein (SHR-CRP), will ameliorate inflammation, oxidative stress, and metabolic disturbances. We studied the effects of FAE treatment by administering Fumaderm, 10 mg/kg body weight for 4 weeks, to male SHR-CRP. Untreated male SHR-CRP rats were used as controls. All rats were fed a high sucrose diet. Compared to untreated controls, rats treated with FAE showed significantly lower levels of endogenous CRP but not transgenic human CRP, and amelioration of inflammation (reduced levels of serum IL6 and TNFα) and oxidative stress (reduced levels of lipoperoxidation products in liver, heart, kidney, and plasma). FAE treatment was also associated with lower visceral fat weight and less ectopic fat accumulation in liver and muscle, greater levels of lipolysis, and greater incorporation of glucose into adipose tissue lipids. Analysis of gene expression profiles in the liver with Affymetrix arrays revealed that FAE treatment was associated with differential expression of genes in pathways that involve the regulation of inflammation and oxidative stress. These findings suggest potentially important anti-inflammatory, anti-oxidative, and metabolic effects of FAE in a model of inflammation and metabolic disturbances induced by human CRP.

• MeSH
• antiflogistika farmakologie   terapeutické užití   MeSH
• antioxidancia farmakologie   terapeutické užití   MeSH
• C-reaktivní protein genetika   MeSH
• fumaráty farmakologie   terapeutické užití   MeSH
• hemodynamika účinky léků   MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• metabolický syndrom farmakoterapie   genetika   metabolismus   patofyziologie   MeSH
• oxidační stres účinky léků   MeSH
• potkani inbrední SHR MeSH
• transkriptom účinky léků   MeSH
• zánět farmakoterapie   genetika   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antiflogistika MeSH
• antioxidancia MeSH
• C-reaktivní protein MeSH
• fumaráty MeSH

Metabolic interactions between adipose tissue and the heart may play an active role in progression of heart failure (HF). The aim of the study was to examine changes in myocardial and adipose tissue metabolism and gene expression in a rat HF model induced by chronic volume overload. HF was induced by volume overload from aorto-caval fistula (ACF) in 3-month-old male Wistar rats and animals were studied in the phase of decompensated HF (22nd week). HF rats showed marked eccentric cardiac hypertrophy, pulmonary congestion, increased LV end-diastolic pressure, and intraabdominal fat depletion. HF rats had preserved glucose tolerance, but increased circulating free fatty acids (FFA) and attenuated insulin response during oral glucose challenge. Isolated organ studies showed preserved responsiveness of adipose tissue lipolysis and lipogenesis to epinephrine and insulin in ACF. The heart of HF animals had markedly reduced triglyceride content (almost to half of controls), attenuated anti-oxidative reserve (GSH/GSSG), upregulated HF markers (ANP, periostin, thrombospondin-4), specific signaling pathways (Wnt, TGF-β), and downregulated enzymes of mitochondrial fatty acid oxidation, citric acid cycle, and respiratory chain. Adipose tissue transcription profiling showed upregulated receptor for gastric inhibitory polypeptide. In conclusion, ACF-induced HF model displays several deregulations of systemic metabolism. Despite elevation of systemic FFAs, myocardial triglycerides are low and insulin levels are attenuated, arguing against a role of lipotoxicity or insulin resistance in this model. Attenuated postprandial insulin response and relative lack of its antilipolytic effects may facilitate intraabdominal fat depletion observed in ACF-HF animals.

• MeSH
• aorta chirurgie   MeSH
• arteriovenózní píštěl MeSH
• arteriovenózní zkrat MeSH
• biologické markery metabolismus   MeSH
• epididymis metabolismus   patologie   MeSH
• glukózový toleranční test MeSH
• glutathion metabolismus   MeSH
• hemodynamika MeSH
• inzulin krev   MeSH
• játra patologie   MeSH
• kardiomyocyty metabolismus   patologie   MeSH
• krysa rodu Rattus MeSH
• kyseliny mastné neesterifikované krev   MeSH
• látky reagující s kyselinou thiobarbiturovou metabolismus   MeSH
• ledviny patologie   MeSH
• metabolismus lipidů MeSH
• myokard metabolismus   patologie   MeSH
• oxidační stres MeSH
• plíce patologie   MeSH
• potkani Wistar MeSH
• remodelace komor MeSH
• srdce patofyziologie   MeSH
• srdeční selhání metabolismus   patologie   patofyziologie   MeSH
• stanovení celkové genové exprese MeSH
• superoxiddismutasa metabolismus   MeSH
• tuková tkáň metabolismus   patologie   MeSH
• velikost orgánu MeSH
• venae cavae chirurgie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• biologické markery MeSH
• glutathion MeSH
• inzulin MeSH
• kyseliny mastné neesterifikované MeSH
• látky reagující s kyselinou thiobarbiturovou MeSH
• superoxiddismutasa MeSH