The objective of our in vitro study was to quantify the biochemical profile where the total polyphenol, flavonoid and phenolic acid content was determined. The antioxidant potential of microgreen extract from Trigonella foenum-graecum L., was measured molybdenum reducing power assay. Specifically, the study assessed parameters such as metabolic activity (AlamarBlueTM assay), membrane integrity (CFDA-AM assay), mitochondrial potential (JC-1 assay), as well as reactive oxygen species generation (NBT assay). In addition, the steroid hormone release in TM3 murine Leydig cells after 12 h and 24 h exposures were quantified by enzyme-linked immunosorbent assay. The gained results indicate the highest value in total flavonoid content (182.59+/-2.13 mg QE) determination, supported by a significant (108.25+/-1.27 mg TE) antioxidant activity. The effects on metabolic activity, cell membrane integrity, and mitochondrial membrane potential were found to be both time- and dose-dependent. Notably, a significant suppression in reactive oxygen species generation was confirmed at 150, 200 and 250 microg/ml after 24 h exposure. In addition, progesterone and testosterone release was stimulated up to 250 microg/ml dose of Trigonella, followed by a decline in both steroid production at 300 and 1000 microg/ml. Our results indicate, that Trigonella at lower experimental doses (up to 250 microg/ml) may positively affect majority of monitored cell parameters in TM3 Leydig cells. Overleaf, increasing experimental doses may negatively affect the intracellular parameters already after 12 h of in vitro exposure. Key words Microgreens, Trigonella foenum-graecum L., Fenugreek, Leydig cells, Male reproduction.
- MeSH
- antioxidancia farmakologie MeSH
- buněčné linie MeSH
- fytonutrienty farmakologie MeSH
- Leydigovy buňky * účinky léků metabolismus MeSH
- membránový potenciál mitochondrií účinky léků MeSH
- myši MeSH
- reaktivní formy kyslíku metabolismus MeSH
- rostlinné extrakty * farmakologie MeSH
- testosteron metabolismus MeSH
- Trigonella * chemie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Extracellular potassium concentration might modify electrophysiological properties in the border zone of ischemic myocardium. We evaluated the depolarization and repolarization characteristics across the ischemic-normal border under [K+] variation. Sixty-four-lead epicardial mapping was performed in 26 rats ([K+] 2.3-6.4 mM) in a model of acute ischemia/reperfusion. The animals with [K+] < 4.7 mM (low-normal potassium) had an ischemic zone with ST-segment elevation and activation delay, a border zone with ST-segment elevation and no activation delay, and a normal zone without electrophysiological abnormalities. The animals with [K+] >4.7 mM (normal-high potassium) had only the ischemic and normal zones and no transitional area. Activation-repolarization intervals and local conduction velocities were inversely associated with [K+] in linear regression analysis with adjustment for the zone of myocardium. The reperfusion extrasystolic burden (ESB) was greater in the low-normal as compared to normal-high potassium animals. Ventricular tachycardia/fibrillation incidence did not differ between the groups. In patch-clamp experiments, hypoxia shortened action potential duration at 5.4 mM but not at 1.3 mM of [K+]. IK(ATP) current was lower at 1.3 mM than at 5.4 mM of [K+]. We conclude that the border zone formation in low-normal [K+] was associated with attenuation of IK(ATP) response to hypoxia and increased reperfusion ESB.
- MeSH
- akční potenciály * fyziologie MeSH
- draslík * krev metabolismus MeSH
- ischemická choroba srdeční * patofyziologie krev metabolismus MeSH
- krysa rodu rattus MeSH
- potkani Wistar MeSH
- reperfuzní poškození myokardu krev patofyziologie metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Aminophylline, a bronchodilator mainly used to treat severe asthma attacks, may induce arrhythmias. Unfortunately, the underlying mechanism is not well understood. We have recently described a significant, on average inhibitory effect of aminophylline on inward rectifier potassium current IK1, known to substantially contribute to arrhythmogenesis, in rat ventricular myocytes at room temperature. This study was aimed to examine whether a similar effect may be observed under clinically relevant conditions. Experiments were performed using the whole cell patch clamp technique at 37°C on enzymatically isolated healthy porcine and failing human ventricular myocytes. The effect of clinically relevant concentrations of aminophylline (10-100 μM) on IK1 did not significantly differ in healthy porcine and failing human ventricular myocytes. IK1 was reversibly inhibited by ∼20 and 30 % in the presence of 30 and 100 μM aminophylline, respectively, at -110 mV; an analogical effect was observed at -50 mV. To separate the impact of IK1 changes on AP configuration, potentially interfering ionic currents were blocked (L-type calcium and delayed rectifier potassium currents). A significant prolongation of AP duration was observed in the presence of 100 μM aminophylline in porcine cardiomyocytes which well agreed with the effect of a specific IK1 inhibitor Ba2+ (10 μM) and with the result of simulations using a porcine ventricular cell model. We conclude that the observed effect of aminophylline on healthy porcine and failing human IK1 might be involved in its proarrhythmic action. To fully understand the underlying mechanism, potential aminophylline impact on other ionic currents should be explored.
- MeSH
- akční potenciály účinky léků MeSH
- aminofylin * farmakologie MeSH
- draslíkové kanály dovnitř usměrňující * metabolismus MeSH
- kardiomyocyty * účinky léků metabolismus MeSH
- lidé MeSH
- metoda terčíkového zámku MeSH
- prasata MeSH
- srdeční komory účinky léků metabolismus MeSH
- srdeční selhání metabolismus farmakoterapie MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Among inherited cardiomyopathies involving the left ventricle, whether dilated or not, certain genotypes carry a well-established arrhythmic risk, notably manifested as sustained monomorphic ventricular tachycardia (SMVT). Nonetheless, the precise localization and electrophysiological profile of this substrate remain undisclosed across different genotypes. METHODS: Patients diagnosed with cardiomyopathy and left ventricle involvement due to high-risk genetic variants and SMVT treated by electrophysiological study were recruited from 18 European/US centers. Electrophysiological study, imaging, and outcomes data after ablation were assessed in relation to genotype. RESULTS: Seventy-one patients were included (49.6 Q1-Q3 [40-60] years, 76% men). They were divided into 4 groups according to the affected protein: desmosomal (DSP, PKP2, DSG2, and DSC2), nuclear membrane (LMNA and TMEM43), cytoskeleton (FLNC and DES), and sarcoplasmic reticulum (PLN). Desmosomal genes, TMEM43, and PLN were associated with biventricular disease, while variants in LMNA and cytoskeleton genes had predominant left ventricle involvement (P=0.001). The location of the clinical-SMVT substrate was significantly different based on genotype (P=0.005). DSP and cytoskeleton genes presented SMVTs with right bundle branch block morphology, which origin was identified in the inferolateral segments of the left ventricle. The other desmosomal genes (PKP2 and DSG2), along with TMEM43, showed SMVTs with left bundle branch block morphology and predominantly right ventricular substrate. In contrast, LMNA substrate was mainly observed in the interventricular septum. During a median of 26 Q1-Q3 (10.6-65) months, 27% of patients experienced recurrences of clinical SMVT with differences between genotypes (log-rank 0.016). Nuclear membrane genes demonstrated the highest recurrence rate compared with desmosomal genes (hazard ratio, 4.56 [95% CI, 1.5-13.8]). CONCLUSIONS: The anatomic substrate of SMVTs shows a strong correlation with the underlying genotype, electrocardiographic morphology, and recurrence rate. Particularly, patients with nuclear membrane gene variants have a significantly higher recurrence rate compared with those with desmosomal gene variants.
- MeSH
- akční potenciály MeSH
- dospělí MeSH
- elektrofyziologické techniky kardiologické MeSH
- fenotyp * MeSH
- genetická predispozice k nemoci * MeSH
- genetické asociační studie MeSH
- genotyp MeSH
- hodnocení rizik MeSH
- kardiomyopatie genetika patofyziologie diagnóza MeSH
- katetrizační ablace MeSH
- komorová tachykardie * genetika patofyziologie diagnóza MeSH
- lidé středního věku MeSH
- lidé MeSH
- rizikové faktory MeSH
- výsledek terapie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- pozorovací studie MeSH
- Geografické názvy
- Evropa MeSH
Mutations in DNA polymerase gamma (POLG) are known as the predominant cause of inherited mitochondrial disorders. But how these POLG mutations disturb mitochondrial function remains to be determined. Furthermore, no effective therapy, to date, has been reported for POLG diseases. Using differentiated SH-SY5Y cells, a human neuronal model cell line, the current study investigated whether the novel POLG variant p.A962T impairs mitochondrial function. This involved quantifying mitochondrial DNA (mtDNA) content using PCR and assessing the expression levels of the subunits of complex IV (COXI-IV), a complex I subunit NDUFV1 and Cytochrome C (Cyto C) release using Western blotting. Activities of mitochondrial complex I, II, and IV were measured using colorimetric assays. Mitochondrial membrane potential (delta Psim) and ATP were evaluated using fluorescence assays and luminescent assays, respectively. In addition, we investigated whether mitochondrial transplantation (MT) using Pep-1-conjugated mitochondria could compensate for mitochondrial defects caused by the variant in cells carrying mutant POLG. The results of this study showed that POLG p.A962T mutation resulted in mitochondrial defects, including mitochondrial DNA (mtDNA) depletion, membrane potential (delta Psim) depolarization and adenosine triphosphate (ATP) reduction. Mechanistically, POLG mutation-caused mtDNA depletion led to the loss of mtDNA-encoded subunits of complex I and IV and thus compromised their activities. POLG p.A962T mutation is a pathogenic mutation leading to mitochondrial malfunction and mtDNA depletion in neurons. Cell-penetrating peptide Pep-1-mediated MT treatment compensated for mitochondrial defects induced by these POLG variants, suggesting the therapeutic application of this method in POLG diseases.
- MeSH
- DNA polymeráza gama * genetika metabolismus MeSH
- DNA-dependentní DNA-polymerasy genetika metabolismus MeSH
- lidé MeSH
- membránový potenciál mitochondrií MeSH
- mitochondriální DNA genetika MeSH
- mitochondriální nemoci genetika metabolismus MeSH
- mitochondrie * metabolismus MeSH
- mutace * MeSH
- nádorové buněčné linie MeSH
- neurony * metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The somatostatin (SST) receptor family controls pituitary hormone secretion, but the distribution and specific roles of these receptors on the excitability and voltage-gated calcium signaling of hormone producing pituitary cells have not been fully characterized. Here we show that the rat pituitary gland expressed Sstr1, Sstr2, Sstr3, and Sstr5 receptor genes in a cell type-specific manner: Sstr1 and Sstr2 in thyrotrophs, Sstr3 in gonadotrophs and lactotrophs, Sstr2, Sstr3, and Sstr5 in somatotrophs, and none in corticotrophs and melanotrophs. Most gonadotrophs and thyrotrophs spontaneously fired high-amplitude single action potentials, which were silenced by SST without affecting intracellular calcium concentrations. In contrast, lactotrophs and somatotrophs spontaneously fired low-amplitude plateau-bursting action potentials in conjunction with calcium transients, both of which were silenced by SST. Moreover, SST inhibited GPCR-induced voltage-gated calcium signaling and hormone secretion in all cell types expressing SST receptors, but the inhibition was more pronounced in somatotrophs. The pattern of inhibition of electrical activity and calcium signaling was consistent with both direct and indirect inhibition of voltage-gated calcium channels, the latter being driven by cell type-specific hyperpolarization. These results indicate that the action of SST in somatotrophs is enhanced by the expression of several types of SST receptors and their slow desensitization, that SST may play a role in the electrical resynchronization of gonadotrophs, thyrotrophs, and lactotrophs, and that the lack of SST receptors in corticotrophs and melanotrophs keeps them excitable and ready to responses to stress.
- MeSH
- akční potenciály účinky léků MeSH
- gonadotropní buňky metabolismus účinky léků MeSH
- hypofýza * metabolismus MeSH
- krysa rodu rattus MeSH
- potkani Wistar MeSH
- receptory somatostatinu * metabolismus genetika MeSH
- somatostatin metabolismus MeSH
- vápník metabolismus MeSH
- vápníková signalizace * účinky léků MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
AIMS: Catheter ablation is an effective treatment method for recurrent ventricular tachycardias (VTs). However, at least in part, procedural and clinical outcomes are limited by challenges in generating an adequate lesion size in the ventricular myocardium. We investigated procedural and clinical outcomes of VT ablation using a novel 'large-footprint' catheter that allows the creation of larger lesions either by radiofrequency (RF) or by pulsed field (PF) energy. METHODS AND RESULTS: In prospectively collected case series, we describe our initial experience with VT ablation using a lattice-tip, dual-energy catheter (Sphere-9, Medtronic), and a compatible proprietary electroanatomical mapping system (Affera, Medtronic). The study population consisted of 18 patients (aged 55 ± 15 years, one woman, structural heart disease: 94%, ischaemic heart disease: 56%, left ventricular ejection fraction: 34 ± 10%, electrical storm: 22%) with recurrent sustained VTs and ≥1 previously failed endocardial RF ablation with conventional irrigated-tip catheter in 66% of patients. On average, 12 ± 7 RF and 8 ± 9 PF applications were delivered per patient. In three-fourths of patients undergoing percutaneous epicardial ablation, spasms in coronary angiography were observed after PF applications. All resolved after intracoronary administration of nitrates. No acute phrenic nerve palsy was noted. One patient suffered from a stroke that resolved without sequelae. Post-ablation non-inducibility of VT was achieved in 89% of patients. Ventricular-arrhythmia-free survival at three months was 78%. CONCLUSION: VT ablation using a dual-energy lattice-tip catheter and a novel electroanatomical mapping system is feasible. It allows rapid mapping and effective substrate modification with good outcomes during short-term follow-up.
- MeSH
- akční potenciály MeSH
- časové faktory MeSH
- design vybavení MeSH
- doba přežití bez progrese choroby MeSH
- dospělí MeSH
- elektrofyziologické techniky kardiologické * MeSH
- katetrizační ablace * metody přístrojové vybavení škodlivé účinky MeSH
- komorová tachykardie * chirurgie patofyziologie diagnóza MeSH
- lidé středního věku MeSH
- lidé MeSH
- prospektivní studie MeSH
- recidiva MeSH
- senioři MeSH
- srdeční katétry * MeSH
- studie proveditelnosti * MeSH
- výsledek terapie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
This work presents results on the efficiency of newly designed zinc phthalocyanine-mediated photodynamic therapy of both tumoral and nontumoral cell models using the MTT assay. Further detailed examinations of mechanistic and cell biological effects were focused on the HELA cervical cancer cell model. Here, ROS production, changes in the mitochondrial membrane potential, the determination of genotoxicity, and protein changes determined by capillary chromatography and tandem mass spectrometry with ESI were analyzed. The results showed that, in vitro, 5 Jcm-2 ZnPc PDT caused a significant increase in reactive oxygen species. Still, except for superoxide dismutase, the levels of proteins involved in cell response to oxidative stress did not increase significantly. Furthermore, this therapy damaged mitochondrial membranes, which was proven by a more than 70% voltage-dependent channel protein 1 level decrease and by a 65% mitochondrial membrane potential change 24 h post-therapy. DNA impairment was assessed by an increased level of DNA fragmentation, which might be related to the decreased level of DDB1 (decrease in levels of more than 20% 24 h post-therapy), a protein responsible for maintaining genomic integrity and triggering the DNA repair pathways. Considering these results and the low effective concentration (LC50 = 30 nM), the therapy used is a potentially very promising antitumoral treatment.
- MeSH
- fotochemoterapie * metody MeSH
- fotosenzibilizující látky * farmakologie chemie MeSH
- HeLa buňky MeSH
- indoly * farmakologie chemie MeSH
- isoindoly * MeSH
- lidé MeSH
- membránový potenciál mitochondrií * účinky léků MeSH
- organokovové sloučeniny * farmakologie chemie MeSH
- oxidační stres účinky léků MeSH
- poškození DNA účinky léků MeSH
- reaktivní formy kyslíku * metabolismus MeSH
- sloučeniny zinku * farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
INTRODUCTION: Left bundle branch area pacing (LBBAP) comprises pacing at the left ventricular septum (LVSP) or left bundle branch (LBBP). The aim of the present study was to investigate the differences in ventricular electrical heterogeneity between LVSP, LBBP, right ventricular pacing (RVP) and intrinsic conduction with different dyssynchrony measures using the ECG, vectorcardiograpy, ECG belt, and Ultrahigh frequency (UHF-)ECG. METHODS: Thirty-seven patients with a pacemaker indication for bradycardia or cardiac resynchronization therapy underwent LBBAP implantation. ECG, vectorcardiogram, ECG belt and UHF-ECG signals were recorded during RVP, LVSP and LBBP, and intrinsic activation. QRS duration (QRSd) was measured from the ECG, QRS area was calculated from the vectorcardiogram, LV activation time (LVAT) and standard deviation of activation time (SDAT) from ECG belt and electrical dyssynchrony (e-DYS16) from UHF-ECG. RESULTS: Both LVSP and LBBP significantly reduced ventricular electrical heterogeneity as compared to underlying LBBB and RV pacing in terms of QRS area (p < .001), SDAT (p < .001), LVAT (p < .001) and e-DYS16 (p < .001). QRSd was only reduced as compared to RV pacing(p < .001). QRS area was similar during LBBP and normal intrinsic conduction, e-DYS16 was similar during LVSP and normal intrinsic conduction, whereas SDAT was similar for LVSP, LBBP and normal intrinsic conduction. For all these variables there was no significant difference between LVSP and LBBP. CONCLUSION: Both LVSP and LBBP resulted in a more synchronous LV activation than LBBB and RVP. Especially LBBP resulted in levels of LV synchrony comparable to normal intrinsic conduction.
- MeSH
- akční potenciály * MeSH
- blokáda Tawarova raménka patofyziologie terapie diagnóza MeSH
- bradykardie patofyziologie terapie diagnóza MeSH
- časové faktory MeSH
- elektrofyziologické techniky kardiologické MeSH
- elektrokardiografie MeSH
- funkce levé komory srdeční * MeSH
- Hisův svazek * patofyziologie MeSH
- kardiostimulace umělá * MeSH
- lidé středního věku MeSH
- lidé MeSH
- mezikomorová přepážka * patofyziologie MeSH
- prediktivní hodnota testů * MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- srdeční frekvence * MeSH
- srdeční resynchronizační terapie MeSH
- vektorkardiografie * metody MeSH
- výsledek terapie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
Lysophosphatidylcholine (LPC) is a bioactive lipid present at high concentrations in inflamed and injured tissues where it contributes to the initiation and maintenance of pain. One of its important molecular effectors is the transient receptor potential canonical 5 (TRPC5), but the explicit mechanism of the activation is unknown. Using electrophysiology, mutagenesis and molecular dynamics simulations, we show that LPC-induced activation of TRPC5 is modulated by xanthine ligands and depolarizing voltage, and involves conserved residues within the lateral fenestration of the pore domain. Replacement of W577 with alanine (W577A) rendered the channel insensitive to strong depolarizing voltage, but LPC still activated this mutant at highly depolarizing potentials. Substitution of G606 located directly opposite position 577 with tryptophan rescued the sensitivity of W577A to depolarization. Molecular simulations showed that depolarization widens the lower gate of the channel and this conformational change is prevented by the W577A mutation or removal of resident lipids. We propose a gating scheme in which depolarizing voltage and lipid-pore helix interactions act together to promote TRPC5 channel opening.
- MeSH
- gating iontového kanálu účinky léků MeSH
- HEK293 buňky MeSH
- kationtové kanály TRPC * metabolismus genetika chemie MeSH
- lidé MeSH
- lysofosfatidylcholiny * metabolismus farmakologie MeSH
- lysofosfolipidy metabolismus farmakologie MeSH
- membránové potenciály účinky léků MeSH
- mutace MeSH
- simulace molekulární dynamiky * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH