12 research outputs found

    Hyperbaric Oxygen Preconditioning Upregulates Heme OxyGenase-1 and Anti-Apoptotic Bcl-2 Protein Expression in Spontaneously Hypertensive Rats with Induced Postischemic Acute Kidney Injury

    Get PDF
    Renal ischemia and reperfusion (I/R) injury is the most common cause of acute kidney injury (AKI). Pathogenesis of postischemic AKI involves hemodynamic changes, oxidative stress, inflammation process, calcium ion overloading, apoptosis and necrosis. Up to date, therapeutic approaches to treat AKI are extremely limited. Thus, the aim of this study was to evaluate the effects of hyperbaric oxygen (HBO) preconditioning on citoprotective enzyme, heme oxygenase-1 (HO-1), pro-apoptotic Bax and anti-apoptotic Bcl-2 proteins expression, in postischemic AKI induced in normotensive Wistar and spontaneously hypertensive rats (SHR). The animals were randomly divided into six experimental groups: SHAM-operated Wistar rats (W-SHAM), Wistar rats with induced postischemic AKI (W-AKI) and Wistar group with HBO preconditioning before AKI induction (W-AKI + HBO). On the other hand, SHR rats were also divided into same three groups: SHR-SHAM, SHR-AKI and SHR-AKI + HBO. We demonstrated that HBO preconditioning upregulated HO-1 and anti-apoptotic Bcl-2 protein expression, in both Wistar and SH rats. In addition, HBO preconditioning improved glomerular filtration rate, supporting by significant increase in creatinine, urea and phosphate clearances in both rat strains. Considering our results, we can also say that even in hypertensive conditions, we can expect protective effects of HBO preconditioning in experimental model of AKI

    Loss of autophagy protein ATG5 impairs cardiac capacity in mice and humans through diminishing mitochondrial abundance and disrupting Ca2+Ca^{\text{2+}} cycling

    Full text link
    Aims Autophagy protects against the development of cardiac hypertrophy and failure. While aberrant Ca2+ handling promotes myocardial remodelling and contributes to contractile dysfunction, the role of autophagy in maintaining Ca2+ homeostasis remains elusive. Here, we examined whether Atg5 deficiency-mediated autophagy promotes early changes in subcellular Ca2+ handling in ventricular cardiomyocytes, and whether those alterations associate with compromised cardiac reserve capacity, which commonly precedes the onset of heart failure. Methods and results RT–qPCR and immunoblotting demonstrated reduced Atg5 gene and protein expression and decreased abundancy of autophagy markers in hypertrophied and failing human hearts. The function of ATG5 was examined using cardiomyocyte-specific Atg5-knockout mice (Atg5−/−). Before manifesting cardiac dysfunction, Atg5−/− mice showed compromised cardiac reserve in response to β-adrenergic stimulation. Consequently, effort intolerance and maximal oxygen consumption were reduced during treadmill-based exercise tolerance testing. Mechanistically, cellular imaging revealed that Atg5 deprivation did not alter spatial and functional organization of intracellular Ca2+ stores or affect Ca2+ cycling in response to slow pacing or upon acute isoprenaline administration. However, high-frequency stimulation exposed stunted amplitude of Ca2+ transients, augmented nucleoplasmic Ca2+ load, and increased CaMKII activity, especially in the nuclear region of hypertrophied Atg5−/− cardiomyocytes. These changes in Ca2+ cycling were recapitulated in hypertrophied human cardiomyocytes. Finally, ultrastructural analysis revealed accumulation of mitochondria with reduced volume and size distribution, meanwhile functional measurements showed impaired redox balance in Atg5−/− cardiomyocytes, implying energetic unsustainability due to overcompensation of single mitochondria, particularly under increased workload. Conclusion Loss of cardiac Atg5-dependent autophagy reduces mitochondrial abundance and causes subtle alterations in subcellular Ca2+ cycling upon increased workload in mice. Autophagy-related impairment of Ca2+ handling is progressively worsened by β-adrenergic signalling in ventricular cardiomyocytes, thereby leading to energetic exhaustion and compromised cardiac reserve

    CaMKII delta C Drives Early Adaptive Ca(2+)Change and Late Eccentric Cardiac Hypertrophy

    Get PDF
    Rationale: CaMKII (Ca2+-Calmodulin dependent protein kinase) delta C activation is implicated in pathological progression of heart failure (HF) and CaMKII delta C transgenic mice rapidly develop HF and arrhythmias. However, little is known about early spatio-temporal Ca(2+)handling and CaMKII activation in hypertrophy and HF. Objective: To measure time- and location-dependent activation of CaMKII delta C signaling in adult ventricular cardiomyocytes, during transaortic constriction (TAC) and in CaMKII delta C transgenic mice. Methods and Results: We used human tissue from nonfailing and HF hearts, 4 mouse lines: wild-type, KO (CaMKII delta-knockout), CaMKII delta C transgenic in wild-type (TG), or KO background, and wild-type mice exposed to TAC. Confocal imaging and biochemistry revealed disproportional CaMKII delta C activation and accumulation in nuclear and perinuclear versus cytosolic regions at 5 days post-TAC. This CaMKII delta activation caused a compensatory increase in sarcoplasmic reticulum Ca(2+)content, Ca(2+)transient amplitude, and [Ca2+] decline rates, with reduced phospholamban expression, all of which were most prominent near and in the nucleus. These early adaptive effects in TAC were entirely mimicked in young CaMKII delta TG mice (6-8 weeks) where no overt cardiac dysfunction was present. The (peri)nuclear CaMKII accumulation also correlated with enhanced HDAC4 (histone deacetylase) nuclear export, creating a microdomain for transcriptional regulation. At longer times both TAC and TG mice progressed to overt HF (at 45 days and 11-13 weeks, respectively), during which time the compensatory Ca(2+)transient effects reversed, but further increases in nuclear and time-averaged [Ca2+] and CaMKII activation occurred. CaMKII delta TG mice lacking delta B exhibited more severe HF, eccentric myocyte growth, and nuclear changes. Patient HF samples also showed greatly increased CaMKII delta expression, especially for CaMKII delta C in nuclear fractions. Conclusions: We conclude that in early TAC perinuclear CaMKII delta C activation promotes adaptive increases in myocyte Ca(2+)transients and nuclear transcriptional responses but that chronic progression of this nuclear Ca2+-CaMKII delta C axis contributes to eccentric hypertrophy and HF

    COMBINED ULTRASOUND AND BIOCHEMICAL SCREENING FOR FETAL ANEUPLOIDY AT 10 – 14 WEEKS OF PREGNANCY: FIRST RESULTS OF TEST PERFORMANCE IN CROATIA

    Get PDF
    Sažetak. Cilj rada. Retrospektivna studija nakon primjene kombiniranog ultrazvučno-biokemijskog testa probira trisomija u prvom tromjesečju trudnoće. Metode. Od veljače 2006. do srpnja 2008. godine probir je učinjen u 1112 trudnica između 10. i 14. tjedna trudnoće. Individualni rizik trisomije 21, 18 i 13 izračunavali smo kombinacijom dobnog rizika trudnice, ultrazvučnih biljega u ploda (debljina nuhalnog nabora – NT, udaljenosti tjeme-trtica – CRL) te biokemijskih biljega u serumu trudnice (slobodni -hCG i PAPP-A), pomoću licenciranog računalnog programa (Typolog). Koncentracije biokemijskih biljega smo određivali imunometrijskom kemiluminiscentnom metodom (IMMULITE). Biokemijske biljege, kao i NT u odnosu na CRL, izrazili smo u obliku višekratnika MoM, u odnosu na dnevne regresijske medijane za odgovarajuću gestaciju u neugroženim trudnoćama. Rezultate smo obradili nakon dovršenih svih ispitanih trudnoća. Ukupno su 62 testirane trudnice imale povećani kombinirani rizik trisomije 21, od kojih je 10 trudnica imalo i povećani rizik trisomije 18/13. Četiri trisomije 21 i jedna trisomija 18 otkrivene su prenatalnom dijagnozom; stopa detekcije bila je 100% (5/5). U trudnica s povećanim rizikom u probiru učinjeno je 7 biopsija koriona i 38 ranih amniocenteza. Udio lažno-pozitivnih rezultata bio je 5.1%. Zaključak. Prvi rezultati provođenja kombiniranog probirnog testa u Hrvatskoj potvrdili su visoku osjetljivost i veću specifičnost, u poredbi s biokemijskim probirnim testom u drugom tromjesečju trudnoće.Objective. Retrospective study of the results of the first-trimester combined screening for fetal trisomies with ultrasound and biochemical markers. Methods. In the period from February 2006 to July 2008, a total of 1112 pregnant-women underwent screening between the 10th and 14th gestational week. Individual risk for trisomies 21, 18 and 13, combining maternal age, ultrasonography (nuchal translucency, crown-rump length) and serum biochemical analytes (free -hCG, PAPP-A) was computed by means of licensed Typolog software. Concentrations of biochemical markers were determined by chemiluminiscent immunometric assay (IMMULITE). Both biochemical markers, as well as NT, were expressed as Multiples of the Median (MoM), based on the regressed medians of the corresponding gestational age in unaffected pregnancies. Results. All studied pregnancies were followed up to term. A total of 62 pregnant women were categorized as high-risk for trisomy 21, and 10 of them had also an elevated risk for trisomies 18/13, respectively. Four trisomies 21 and one trisomy 18 were detected through combined test and confirmed with prenatal diagnostic procedure. Detection rate was 100%. In those with high risk, 7 chorionic villi sampling and 38 amniocenteses were performed. False-positive rate was 5.1%. Conclusion. The results of the first-trimester screening in Croatia confirmed high sensitivity and better specificity of the combined ultrasonic and biochemical markers, in relation with the second-trimester biochemical screening test

    COMBINED ULTRASOUND AND BIOCHEMICAL SCREENING FOR FETAL ANEUPLOIDY AT 10 – 14 WEEKS OF PREGNANCY: FIRST RESULTS OF TEST PERFORMANCE IN CROATIA

    Get PDF
    Sažetak. Cilj rada. Retrospektivna studija nakon primjene kombiniranog ultrazvučno-biokemijskog testa probira trisomija u prvom tromjesečju trudnoće. Metode. Od veljače 2006. do srpnja 2008. godine probir je učinjen u 1112 trudnica između 10. i 14. tjedna trudnoće. Individualni rizik trisomije 21, 18 i 13 izračunavali smo kombinacijom dobnog rizika trudnice, ultrazvučnih biljega u ploda (debljina nuhalnog nabora – NT, udaljenosti tjeme-trtica – CRL) te biokemijskih biljega u serumu trudnice (slobodni -hCG i PAPP-A), pomoću licenciranog računalnog programa (Typolog). Koncentracije biokemijskih biljega smo određivali imunometrijskom kemiluminiscentnom metodom (IMMULITE). Biokemijske biljege, kao i NT u odnosu na CRL, izrazili smo u obliku višekratnika MoM, u odnosu na dnevne regresijske medijane za odgovarajuću gestaciju u neugroženim trudnoćama. Rezultate smo obradili nakon dovršenih svih ispitanih trudnoća. Ukupno su 62 testirane trudnice imale povećani kombinirani rizik trisomije 21, od kojih je 10 trudnica imalo i povećani rizik trisomije 18/13. Četiri trisomije 21 i jedna trisomija 18 otkrivene su prenatalnom dijagnozom; stopa detekcije bila je 100% (5/5). U trudnica s povećanim rizikom u probiru učinjeno je 7 biopsija koriona i 38 ranih amniocenteza. Udio lažno-pozitivnih rezultata bio je 5.1%. Zaključak. Prvi rezultati provođenja kombiniranog probirnog testa u Hrvatskoj potvrdili su visoku osjetljivost i veću specifičnost, u poredbi s biokemijskim probirnim testom u drugom tromjesečju trudnoće.Objective. Retrospective study of the results of the first-trimester combined screening for fetal trisomies with ultrasound and biochemical markers. Methods. In the period from February 2006 to July 2008, a total of 1112 pregnant-women underwent screening between the 10th and 14th gestational week. Individual risk for trisomies 21, 18 and 13, combining maternal age, ultrasonography (nuchal translucency, crown-rump length) and serum biochemical analytes (free -hCG, PAPP-A) was computed by means of licensed Typolog software. Concentrations of biochemical markers were determined by chemiluminiscent immunometric assay (IMMULITE). Both biochemical markers, as well as NT, were expressed as Multiples of the Median (MoM), based on the regressed medians of the corresponding gestational age in unaffected pregnancies. Results. All studied pregnancies were followed up to term. A total of 62 pregnant women were categorized as high-risk for trisomy 21, and 10 of them had also an elevated risk for trisomies 18/13, respectively. Four trisomies 21 and one trisomy 18 were detected through combined test and confirmed with prenatal diagnostic procedure. Detection rate was 100%. In those with high risk, 7 chorionic villi sampling and 38 amniocenteses were performed. False-positive rate was 5.1%. Conclusion. The results of the first-trimester screening in Croatia confirmed high sensitivity and better specificity of the combined ultrasonic and biochemical markers, in relation with the second-trimester biochemical screening test

    Proizvodnja i percepcija govora

    Get PDF
    Zbornik radova okupio je 57 domaćih i inozemnih autora/ica, koji/e kroz 33 rada, iz različitih istraživačkih kutova, obrađuju recentne teme o proizvodnji i percepciji govora, te o njihovoj međuovisnosti u govornom procesu. Knjiga je posvećena profesoru Damiru Horgi povodom njegova sedamdesetog rođendana. Uz svaki rad naveden je sažetak na hrvatskom i engleskom jeziku. Zbornik je objavljen u suizdavaštvu Odsjeka za fonetiku Filozofskog fakulteta Sveučilišta u Zagrebu, Odjela za fonetiku Hrvatskoga filološkog društva i FF-pressa.Zbornik radova okupio je 57 domaćih i inozemnih autora/ica, koji/e kroz 33 rada, iz različitih istraživačkih kutova, obrađuju recentne teme o proizvodnji i percepciji govora, te o njihovoj međuovisnosti u govornom procesu. Knjiga je posvećena profesoru Damiru Horgi povodom njegova sedamdesetog rođendana. Uz svaki rad naveden je sažetak na hrvatskom i engleskom jeziku. Zbornik je objavljen u suizdavaštvu Odsjeka za fonetiku Filozofskog fakulteta Sveučilišta u Zagrebu, Odjela za fonetiku Hrvatskoga filološkog društva i FF-pressa

    Proizvodnja i percepcija govora

    Get PDF
    Zbornik radova okupio je 57 domaćih i inozemnih autora/ica, koji/e kroz 33 rada, iz različitih istraživačkih kutova, obrađuju recentne teme o proizvodnji i percepciji govora, te o njihovoj međuovisnosti u govornom procesu. Knjiga je posvećena profesoru Damiru Horgi povodom njegova sedamdesetog rođendana. Uz svaki rad naveden je sažetak na hrvatskom i engleskom jeziku. Zbornik je objavljen u suizdavaštvu Odsjeka za fonetiku Filozofskog fakulteta Sveučilišta u Zagrebu, Odjela za fonetiku Hrvatskoga filološkog društva i FF-pressa.Zbornik radova okupio je 57 domaćih i inozemnih autora/ica, koji/e kroz 33 rada, iz različitih istraživačkih kutova, obrađuju recentne teme o proizvodnji i percepciji govora, te o njihovoj međuovisnosti u govornom procesu. Knjiga je posvećena profesoru Damiru Horgi povodom njegova sedamdesetog rođendana. Uz svaki rad naveden je sažetak na hrvatskom i engleskom jeziku. Zbornik je objavljen u suizdavaštvu Odsjeka za fonetiku Filozofskog fakulteta Sveučilišta u Zagrebu, Odjela za fonetiku Hrvatskoga filološkog društva i FF-pressa

    Measuring intranuclear and nuclear envelope [Ca(2+)] vs. cytosolic [Ca (2+)].

    No full text
    Nuclear Ca(2+) regulates key cellular processes, including gene expression, apoptosis, assembly of the nuclear envelope, and nucleocytoplasmic transport. Quantification of subcellularly resolved Ca(2+) signals is, therefore, essential for understanding physiological and pathological processes in various cell types. However, the properties of commonly used Ca(2+)-fluorescent indicators in intracellular compartments may differ, thus affecting the translation of Ca(2+)-dependent fluorescence changes into quantitative changes of Ca(2+) concentration. Here, we describe technical approaches for reliable subcellular quantification of [Ca(2+)] in the cytoplasm vs. the nucleus and the nuclear envelope by in situ calibration of fluorescein-derived fluorescent indicators Fluo-4 and Fluo-5N
    corecore