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1072. Oxidative stress in the brain tissue of laboratory mice with acute post insulin hypoglycemia
- Creator:
- Jitka Patočková, Petr Marhol, Eva Tůmová, Miloslav Kršiak, Richard Rokyta, Stanislav Štípek, Jiřina Crkovská, and Michal Anděl
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, hypoglykémie, hypoglycemia, malondialdehyde, Cu, Zn-superoxide dismutase, selenium-dependent glutathione peroxidase, insulin-induced hypoglycemia, 14, and 612
- Language:
- English
- Description:
- Malondialdehyde (MDA), Cu,Zn-superoxide dismutase (Cu,Zn-SOD) and selenium-dependent glutathione peroxidase (GSPHx) are currently considered to be basic markers of oxidative stress. MDA is one of the end-products of the peroxidation of membrane lipids, whereas enzymes Cu,Zn-SOD and GSHPx belong to the natural antioxidants. The role of oxygen free radicals in the pathogenesis of many diseases is well documented. The aim of this study was to ascertain the influence of insulin-induced acute hypoglycemia on oxidative stress in the brain tissue. Hypoglycemia was induced in ICR mice by intraperitoneal administration of insulin at a dose 24 IU/kg. There was a correlation between the severity of hypoglycemia and the levels of MDA, Cu,Zn-SOD and GSHPx. The results showed that in severe hypoglycemia (serum glucose concentration below 1.0 mmol/l) the lipoperoxidation in brain tissue expressed as the level of MDA was higher in comparison with normoglycemic controls (glycemia around 3.7 mmol/l) as well as in comparison with the levels of MDA during moderate hypoglycemia (glycemia ranging between 1-2 mmol/l). This indicates the enhancement of lipoperoxidation in the brain tissue during severe hypoglycemia. However, both enzymes - Cu,Zn-SOD or GSHPx - did not show a similar tendency., J. Patočková, P. Marhol, E. Tůmová, M. Kršiak, R. Rokyta, S. Štípek, J. Crkovská, M. Anděl., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1073. Oxidative stress induced by epileptic seizure and its attenuation by melatonin
- Creator:
- Jan Mareš, Stopka, P., Kateryna Nohejlová, and Richard Rokyta
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, volné radikály, melatonin, free radicals, seizure, EPR, 14, and 612
- Language:
- English
- Description:
- An epileptic seizure and postictal period in addition to well-known features are also characterize d by massive consumption of energy. This is thought to lead to oxidative stress and increased generation of free radicals, which is reflected by increased levels of oxidative products. Our previous work described the neuroprotective effects of melatonin in preventing cognitive worsening after a single epileptic seizure. This work was aimed on direct measurement of free radicals in brain tissue using the EPR method 1, 15 and 60 minutes after seizure. The measurement was performed in adult male Wistar rats at the mentioned intervals after a single tonic-clonic seizure induced by flurothyl. In comparison to control animals there was a significant increase in hydroxyl and nitroxyl radicals 60 minutes after the seizure. The levels of hydroxyl radicals were significantly lower in animals that received melatonin 60 minutes before seizure induction compared to animals without preventive treatment. Therefore, melatonin affected th e generation of the measured free radicals differently. An important finding was the delayed increase in free radicals after a single seizure in the later phases of recovery., J. Mareš ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1074. Oxidative stress plays an important role in zoledronic acid-induced autophagy
- Creator:
- Khandelwal, V. K. M., Mitrofan, L. M., Hyttinen, J. M. T., Chaudhari, K. R., Buccione, R., Kaarniranta, K., Ravingerová, T., and Mönkkönen, J.
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, oxidační stres, oxidative stress, dendra2, GGOH, FOH, LC3B, prenylation, 14, and 612
- Language:
- English
- Description:
- Several pre-clinical and clinical studies have demonstrated zoledronic acid (Zol), which regulates the mevalonate pathway, has efficient anti-cancer effects. Zol can also induce autophagy. The aim of this study is to add new understanding to the mechanism of autophagy induction by Zol. LC3B-II, the marker for autophagy was increased by Zol treatment in breast cancer cells. Autophagosomes induced by Zol were visualized and quantified in both transient (pDendra2-hLC3) and stable MCF-7- GFP-LC3 cell lines. Acidic vesicular organelles were quantified using acridine orange. Zol induced a dose and time dependent autophagy. Treatment of Zol increased oxidative stress in MCF-7 cells, which was reversed by GGOH or anti-oxidants. On the other hand, treatment with GGOH or anti-oxidants resulted in decreased levels of LC3B-II. Further, the induced autophagy was irreversible, as the washout of Zol after 2 h or 24 h resulted in similar levels of autophagy, as induced by continuous treatment after 72 h. Thus, it can be summarized that Zol can induce a dose dependent but irreversible autophagy, by its effect on the mevalonate pathway and oxidative stress. This study adds to the understanding of the mechanism of action of Zol, and that it can induce autophagy at clinically relevant shorter exposure times in cancer cells., V. K. M. Khandelwal, L. M. Mitrofan, J. M. T. Hyttinen, K. R. Chaudhari, R. Buccione, K. Kaarniranta, T. Ravingerová, J. Mönkkönen., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1075. Oxime reactivators and their in vivo and in vitro effects on nicotinic receptors
- Creator:
- Soukup, O., Jan Krůšek, Kaniaková, M., Kumar, U. K., Oz, M., Daniel Jun, Josef Fusek, Kamil Kuča, and Tobin, G.
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, organofosfáty, organophosphates, patch-clamp, nicotinic receptors, reactivator, isometric muscle contraction, TE671 cells, 14, and 612
- Language:
- English
- Description:
- Current treatment of organophosphorus poisoning, resulting in overstimulation and desensitization of muscarinic and nicotinic receptors by acetylcholine (ACh), consists of the administration of atropine and oxime reactiva tors. However, no versatile oxime reactivator has been developed yet and some mortality still remains after application of standard atropine treatment, probably due to its lack of antinicotinic action. In our study, we focused on the interesting non-acetylcholinesterase property of oximes, i.e. antinicotinic effect of reactivators. Two standard reactivators (HI-6, obidoxime) and two new compounds (K027 and K203) were chosen for in vitro (patch clamp) and in vivo (nerve-evoked muscle contraction) testings. Both examinations showed antinicotinic effects of the reactivators. In vitro inhibition of acetylcholine-evoked currents by obidoxime, HI-6 and K203 was equivalent while K027 was less potent. Similar order of potency was observed by the in vivo examinations. We thus confirm previous in vitro results, which describe antinicotinic effects of oxime reactivators, and furthermore, we show in vivo antagonism of oxime reactivators exerted by the inhibition of ACh effect on the nicotinic receptor in the neuromuscular junction. Taking to gether, the effects of tested oxime reactivators indicate an antagonism on both embryonic and adult form of the muscle nicotinic receptors., O. Soukup ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1076. Ozone-induced micronuclei frequency in rat alveolar type II cells
- Creator:
- Chorvatovičová, D., Hoet, P. H. M., Tátrai, E., and Zuzana Kováčiková
- Format:
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, ozon, ozone, micronuclei, alveolar epithelial type II cells, in vitro, 14, and 612
- Language:
- English
- Description:
- The effect of ozone, a ubiquitous air pollutant, was tested on cultured pulmonary epithelial type II cells isolated from rats. After 40-hour culture, the cells were exposed for 6 h to 400 ppb of ozone or air. The number of micronucleated cells was counted after the exposure. In each group, 17 000 cells were evaluated. The number of micronucleated cells was significantly increased in the ozone-exposed group (12.24 per 1000 cells) compared to the control group (5.00 per 1000 cells). The results showed the mutagenic effect of ozone exposure on alveolar type II cells, manifested in the increased frequency of their micronuclei., D. Chorvatovičová, P.H.M. Hoet, E. Tátrai, Y. Kováčiková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1077. P wave body surface isointegral maps in children and in young adults
- Creator:
- Katarína Kozlíková
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, elektrokardiografie, electrocardiography, body surface mapping, heart atria, 14, and 612
- Language:
- English
- Description:
- Only limited data are available on body surface potential distribution during atrial activation. The aim of this study was to establish the distributions and to analyze chosen quantitative parameters of atrial isointegral maps recorded using a limited 24-lead system in a young healthy population. A total of 166 subjects underwent a procedure of body surface potential mapping. Isointegral maps during the P wave were constructed and qualitatively and quantitatively evaluated. Three types of atrial activation in individual maps were found according to the different shape of the zero isointegral line and to mutual positions of extrema. The most frequently occurring type resembled the group mean maps and was in good agreement with published data obtained from full lead systems. The highest extrema were found in the young men group, while, surprisingly, the lowest values in the young women group. All minima and the majority of maxima were recorded outside the ranges of standard chest leads. The usefulness of the limited lead system to record isointegral P wave maps was shown and new data were presented that can be useful in noninvasive evaluation of atrial pathologies., K. Kozlíková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1078. Pain perception in neurodevelopmental animal models of schizophrenia
- Creator:
- Miloslav Franěk, Šimon Vaculín, Anna Yamamotová, František Šťastný, Věra Valešová, and Richard Rokyta
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, neuropatická bolest, neuropathic pain, quinolinic acid, N-acetyl-aspartyl-glutamate, rat, 14, and 612
- Language:
- English
- Description:
- Animal models are important for the investigation of mechanisms and therapeutic approaches in various human diseases, including schizophrenia. Recently, two neurodevelopmental rat models of this psychosis were developed based upon the use of subunit selective N-methyl-D-aspartate receptor agonists - quinolinic acid (QUIN) and N-acetyl-aspartyl-glutamate (NAAG). The aim of this study was to evaluate pain perception in these models. QUIN or NAAG was infused into lateral cerebral ventricles neonatally. In the adulthood, the pain perception was examined. The rats with neonatal brain lesions did not show any significant differences in acute mechanical nociception and in formalin test compared to controls. However, the neonatally lesioned rats exhibited significantly higher pain thresholds in thermal nociception. Increased levels of mechanical hyperalgesia, accompanying the sciatic nerve constriction (neuropathic pain), were also observed in lesioned rats. Although hyperalgesia was more pronounced in QUIN-treated animals, the number of c-Fos-immunoreactive neurons of the lumbar spinal cord was similar in experimental and control rats. We conclude that neonatal brain lesions attenuated the thermal perception in both nociceptive and neuropathic pain whereas mechanical pain was increased in the model of neuropathic pain only. Thus, nociceptive and neuropathic pain belongs - in addition to behavioral changes - among the parameters which are affected in described animal models of schizophrenia., M. Franěk ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1079. Pancreatic injury secondary to renal ischemia/reperfusion (I/R) injury: possible role of oxidative stress
- Creator:
- Hussein, A. M., Abd-Elkhabir, A., Abozahra, A., Baiomy, A., Ashamallah, S. A., Sheashaa, H. A., and Sobh, M. A.
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, ischemie, pankreas, oxidační stres, ischemia, pancreas, oxidative stress, renal, reperfusion, 14, and 612
- Language:
- English
- Description:
- Recent studies demonstrated remote effects of renal ischemia/reperfusion (I/R) injury on some organs such as brain, liver, and lungs. We investigated the effects of renal I-R injury on function, histology and oxidative stress state of pancreas. Twenty -four male adult Sprague-Dawley rats were divided equally into 2 groups; sham group: rats underwent midline laparotomy and dissection of renal pedicles without renal ischemia, and ischemic group: rats underwent bilateral renal ischemia for 45 min. Renal functions (serum creatinine and BUN), pancreatic functions (serum amylase, lipase and insulin) and fasting blood glucose were measured at 2 h, 1 day, 3 days and 7 days after ischemia. Also, pancreatic histology and malondialdehyde (MDA), catalase and reduced glutathione (GSH) were examined at 2 h and 7 days after ischemia. The ischemic rats showed significant increase in serum creatinine and BUN with significant increase in serum amylase and lipase at 2 h, 1 day and 3 days after ischemia. Blood glucose and fasting insulin showed no significant change apart from significant increase in insulin in sham group at 1 day after ischemia. Pancreas isolated from ischemic rats showed significant increase in histopathological damage score and significant increase in MDA and catalase enzyme with decrease in GSH. In conclusion, bilateral renal ischemia for 45 min caused significant impairment of pancreatic functions and histology. This might be due to deficiency of antioxidant and increased lipid peroxidations in pancreatic tissues., A. M. Hussein ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1080. Paraoxonase 1 gene polymorphisms and enzyme activities in diabetes mellitus
- Creator:
- Flekač, Milan, Jan Škrha, Kateřina Zídková, Zdeňka Lacinová, and Jiřina Hilgertová
- Format:
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, diabetologie, diabetické angiopatie, human physiology, diabetology, diabetic angiopathies, paraoxonase, genetic polymorphisms, serum activity, 14, and 612
- Language:
- English
- Description:
- Paraoxonase 1 (PON1), an antioxidant enzyme closely associated with HDL (high-density lipoproteins), preserves LDL (low-density lipoproteins) against oxidation. Less protection may be therefore supposed by decreased PON1 activity. This study was undertaken to investigate the association of PON1 gene polymorphisms with diabetic angiopathy and to evaluate the relationship of these polymorphisms with PON1 activity. Total of 86 Type 1 (T1DM) and 246 Type 2 (T2DM) diabetic patients together with 110 healthy subjects were examined. DNA isolated from leukocytes was amplified with polymerase chain reaction (PCR) followed by restriction enzyme digestion. The products were analyzed for L55M and Q192R polymorphisms in coding region and for –107 C/T and –907 G/C in promotor sequence of PON1. Serum enzyme activity was measured spectrophotometrically. Significant differences were found between T1DM or T2DM and control persons in L55M polymorphism (allele M more frequent in T1DM and T2DM vs. controls, p<0.05) and Q192R polymorphism (R allele less frequent in T1DM and T2DM vs. controls, p<0.01) of the PON1 gene. Serum PON1 activity was significantly decreased in T1DM (110±68 nmol/ml/min) and T2DM patients (118±69 nmol/ml/min) compared to the control persons (203±58 nmol/ml/min), both p<0.01. The presence of MM and QQ genotypes was accompanied by lower PON1 activity than of LL and RR genotypes (p<0.05), respectively. Better diabetes control was found in patients with LL than with MM genotypes and similarly in RR genotype than QQ genotype with p<0.05. Significantly different allele frequencies were found in diabetic patients with macroangiopathy than in those without it (M: 0.59 vs. 0.44. R: 0.12 vs. 0.19, p<0.01). The association of PON1 polymorphisms, lower PON1 activity and poorer diabetes control found in patients with macroangiopathy further support the idea of genetic factors contributing to the development of vascular disorders in diabetes., M. Flekač, J. Škrha, K. Zídková, Z, Lacinová, J. Hilgertová., and Obsahuje bibliografii a biblografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public