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Effect of Phenylhydrazine-induced hemolytic anemia on morphological changes of renal cortex in adult mice: Protective effect of crocin.
2018
Adibmoradi, Masood | Kalantari hesari, ali | Shahrooz, Rasoul | Asadi, Mohammad Reza
BACKGROUND: Hemolytic anemia and resultant hypoxia can cause a dysfunction in the body functions. Iron delivered from hemolysis of erythrocytes can also stimulate oxidative stress. OBJECTIVES: In this study, we aimed to investigate the protective effect of crocin on renal quality in animals that were exposed against hemolytic anemia induced by phenilhydrazine. METHODS: Forty-nine male and adult mice (20 – 25 g) were grouped within 7 groups. First group was control and treated with normal saline, and test groups were nominated as 2, 3, and 4 and were treated with phenyl hydrazine 2, 4, and 6 mg/100g/48 h (i.p.). Animals in groups 5, 6, and 7 were treated with crocin (200 mg/k/day, i.p.) in addition of 2, 4, and 6 mg/100g/48 h phenyl hydrazine. After 35 days, the blood samples were collected directly from the heart and after centrifugation (5 min and 3000 rpm), the serum samples were subjected to evaluate the Malondialehyde (MAD) level and total antioxidant capacity (TAC), and renal were fixed in 10% formal saline for Paraffin sections. After tissue processing sample staining with H&E method. RESULTS: This study showed that hemolytic anemia effects in proximal tubule of renal cortex, elso showed that the phenylhydrazine administration resulted in a dose-dependent declining of TAC and the crocin administration slightly was able to protect from TAC reduction. Moreover, PHN increased MDA level in serum in a dose-dependent manner, while co-administration of crocin with PHN significantly (P<0.05) reduced the rate of lipid peroxidation.while those groups which were treated with crocin showed a remarkable improvement in testis parameters. CONCLUSIONS: These results indicate a protective effect of Crocin against the anemia-related hypoxia on renal parameters. The protective capacity of Crocin might relate to its known antioxidant power.
Показать больше [+] Меньше [-]Modulators of KATP channels in the prevention of oxidative stress and antioxidant capacity improvement in the rat heart with different resistance to hypoxia upon cobalt treatment
2016
Kurhaluk Natalia | Tkachenko Halyna
Introduction: The main goal of the study was to investigate the effect of KATP channel modulators on development of oxidative stress in the heart of rats showing different resistance to hypoxia.
Показать больше [+] Меньше [-]Estrogen-related receptor α (ERRα) functions in the hypoxic injury of microglial cells
2022
Deng, Chao-Yang | Zhu, Ting-Ting | Lian, Shuai | Wang, Jian-Fa | Wu, Rui | Zheng, Jia-San
Hypoxia is a common pathological condition after spinal cord injury. Oestrogen-related receptor alpha (ERRα), as a key regulator of energy metabolism and mitochondrial functions, plays an important role in maintaining cell homeostasis. However, its role in hypoxic spinal microglia has not been fully elaborated. This study investigated the receptor’s activity when these cells are hypoxic and used as an in vitro model. In this study, microglia (BV2) were exposed to cobalt chloride as a hypoxic model, and the inverse agonist of ERRα, XCT790, and pyrido[1,2-α]-pyrimidin-4-one were used to regulate the expression of the receptor to explore the ERRα-related mechanisms involved in hypoxic spinal cord injury (SCI). ERRα promoted autophagy in BV2 cells and inhibited the activation of the p38 mitogen-activated protein kinase (MAPK) pathway and the expression of anti-inflammatory factors under hypoxic conditions. It also promoted the expression of fibronectin type III domain containing protein 5 (FNDC5). When a hypoxic SCI occurs, ERRα may maintain the homeostasis of spinal cord nerve cells by regulating autophagy and the p38MAPK/nuclear factor-kappa B cell and FNDC5/brain-derived neurotrophic factor signalling pathways, which are beneficial to the recovery of these cells.
Показать больше [+] Меньше [-]Disorders in blood circulation as a probable cause of death in dogs infected with Babesia canis
2021
The purpose of the study was to investigate post-mortem changes in dogs infected with Babesia canis and to establish the probable cause of death of the affected animals. Cadavers of six dogs that did not survive babesiosis were collected. Necropsies were performed and samples of various organs were collected for histological examination. Necropsies and histological examinations revealed congestion and oedemata in various organs. Most of the dogs had ascites, hydrothorax or hydropericardium, pulmonary oedema, pulmonary, renal, hepatic, and cerebral congestion, and necrosis of cardiomyocytes. These results suggested disorders in blood circulation as the most probable cause of death. However, the pulmonary inflammatory response and cerebral babesiosis observed in some of these dogs could also be considered possible causes of death. This study also showed a possible role for renal congestion in the development of renal hypoxia and azotaemia in canine babesiosis.
Показать больше [+] Меньше [-]Modulators of KATP channels in the prevention of oxidative stress and antioxidant capacity improvement in the rat heart with different resistance to hypoxia upon cobalt treatment
2016
Kurhaluk, Natalia | Tkachenko, Halyna
Introduction: The main goal of the study was to investigate the effect of KATP channel modulators on development of oxidative stress in the heart of rats showing different resistance to hypoxia.Material and Methods: The study has been performed on rats showing high- (HR) or low-resistance (LR) to hypoxia under modulators of ATP-sensitive potassium (KATP) channel opener pinacidil (0.06 mg/kg) and blocker glibenclamide (1 mg/kg) upon cobalt (Co) treatment (30 mg of cobalt chloride/kg b.w., 3 h). Changes in the oxidative stress parameters of the heart tissue, such as lipid peroxidation (LPO), level of oxidatively modified protein (OMP), and antioxidant defence system (superoxide dismutase - SOD, catalase -CAT, glutathione peroxidase - GPx, glutathione reductase - GR) as well as total antioxidant activity (TAA) were analysed.Results: Co treatment caused a significant decrease in SOD and CAT activity in the heart of LR rats and GPx activity in HR rats. It also led to a decrease in OMP level in the heart of rats with HR in comparison with controls.Conclusion: The obtained results suggest that individual resistance to hypoxia plays a crucial role in Co actions and provides evidence that the effects of KATP channel opener pinacidil in the heart are mediated through different pathways of the antioxidative system, depending on the individual resistance to hypoxia. Pinacidil exerts a protective effect on the heart tissue by preventing the LPO decrease and significantly reducing OMP levels, as well as increasing TTA in rats with LR.
Показать больше [+] Меньше [-]Effects of pulse-delivered inhaled nitric oxide administration on pulmonary perfusion and arterial oxygenation in dorsally recumbent isoflurane-anesthetized horses
2014
Grubb, Tamara L. | Lord, Peter F. | Berger, Mieth | Larsson, Christina | Ryden, Anneli | Frendin, Jan | Funkquist, Pia | Edner, Anna | Nyman, Gorel
Objective—To image the spatial distribution of pulmonary blood flow by means of scintigraphy, evaluate ventilation-perfusion (VA/Q) matching and pulmonary blood shunting (Qs/Qt) by means of the multiple inert gas elimination technique (MIGET), and measure arterial oxygenation and plasma endothelin-1 concentrations before, during, and after pulse-delivered inhaled nitric oxide (PiNO) administration to isoflurane-anesthetized horses in dorsal recumbency. Animals—3 healthy adult Standardbreds. Procedures—Nitric oxide was pulsed into the inspired gases in dorsally recumbent isoflurane-anesthetized horses. Assessment of VA/Q matching, Qs/Qt, and Pao2 content was performed by use of the MIGET, and spatial distribution of pulmonary blood flow was measured by perfusion scintigraphy following IV injection of technetium Tc 99m–labeled macroaggregated human albumin before, during, and 30 minutes after cessation of PiNO administration. Results—During PiNO administration, significant redistribution of blood flow from the dependent regions to the nondependent regions of the lungs was found and was reflected by improvements in VA/Q matching, decreases in Qs/Qt, and increases in Pao2 content, all of which reverted to baseline values at 30 minutes after PiNO administration. Conclusions and Clinical Relevance—Administration of PiNO in anesthetized dorsally recumbent horses resulted in redistribution of pulmonary blood flow from dependent atelectatic lung regions to nondependent aerated lung regions. Because hypoxemia is commonly the result of atelectasis in anesthetized dorsally recumbent horses, the addition of nitric oxide to inhaled gases could be used clinically to alleviate hypoxemia in horses during anesthesia.
Показать больше [+] Меньше [-]Regulation of respiratory muscle activities during chemoreceptor stimulation in adult horses
1995
Ainsworth, D.M. | Ducharme, N.G. | Hackett, R.P. | Eicker, S.W. | Snedden, K.
We examined the electromyographic activity of the costal portion of the diaphragm and the transverse abdominal and external oblique muscles in 6 chronically instrumented awake adult horses during eupneic breathing during 2 levels of hypercapnia (fractional concentration of inspired CO2; FICO2 = 0.4 and 0.6), and during 2 levels of hypocapnic hypoxia (FIO2 = 0.15 and 0.12). Using the inert gas technique, we also measured the end-expiratory lung volumes of the 6 horses during eupnea, 6% CO2 challenge, and 12% O2 breathing. During eupneic breathing, phasic electrical activity of these 3 muscles was always present and was preceded by the onset of mechanical flow. At progressive levels of hypercapnia, the magnitude of inspiratory and expiratory electrical activity increased, and for the expiratory muscles, this recruitment coincided with significant (P < 0.05) increases in peak expiratory gastric pressure. However, during hypocapnic hypoxia, differential recruitment patterns of the respiratory muscles were found. The electrical activity of the diaphragm increased in magnitude and occurred sooner relative to the onset of mechanical flow. The magnitude and onset of abdominal expiratory activity failed to increase significantly during these episodes of hyperpnea and this pattern of activity coincided with decrements in peak expiratory gastric pressure. Despite alterations in muscle recruitment patterns during these hyperpneic episodes, end-expiratory lung volume remained unchanged. Thus, we conclude that adult horses respond similarly to awake dogs during peripheral and central chemoreceptor stimulation.
Показать больше [+] Меньше [-]Effects of superoxide dismutase on injury induced by anoxia and reoxygenation in equine small intestine in vitro
1991
Johnston, J.K. | Odoh, Bethrand Toochukwu | Gillette, D. | Soma, L.R.
Sheets of mucosa from the jejunum of healthy horses were mounted in incubation chambers and bathed with Krebs-ringer bicarbonate solution. Changes in tissue function and histologic appearance were compared after the following conditions: (1) control conditions for 30 minutes with 95% O2/5% CO2 in the gas phase; (2) same conditions as control, except incubation with superoxide dismutase (300 U/ml) during the last 18 minutes; (3) anoxia for 15 minutes with 95% N2/5% CO2, followed by reoxygenation for 15 minutes; (4) same conditions as 3, except incubation with superoxide dismutase during reoxygenation; and (5) anoxia for 30 minutes. Anoxia reduced the accumulation of radiolabeled L-alanine and caused cell swelling, as indicated by an increase in tissue water and tissue Na contents. Reoxygenation improved the tissue's ability to accumulate L-alanine, but tissue swelling continued after this treatment. Tissue Na content and L-alanine accumulation were restored to control values by reoxygenation with superoxide dismutase in the bathing medium. The grade of structural damage, as indicated by separation of eptihelial cells from villi, was equally severe after all, but control, conditions. Superoxide dismutase had no effect on the tissue control conditions. Results of this study suggest that superoxide radicals are involved in the pathogenesis of reperfusion injury in equine jejunal mucosa and that this may be of clinical importance in cases of small intestinal strangulation obstruction.
Показать больше [+] Меньше [-]Cardiopulmonary effects of positive end-expiratory pressure in anesthetized, mechanically ventilated ponies
1990
Wilson, D.V. | Soma, L.R.
To investigate the cardiopulmonary effects of positive end-expiratory pressure (PEEP), values of 10, 20, and 30 cm of H2O, were applied to anesthetized, dorsally recumbent, ventilated ponies. After IV induction of general anesthesia, PEEP was superimposed on controlled ventilation with 100% oxygen, and changes in gas exchange and cardiac function were measured. Increasing values of PEEP in these ponies caused a linear increase in the mean (+/- SEM) functional residual capacity, from a control value (zero end-expiratory pressure) of 1.7 +/- 0.24 L to 2.2 +/- 0.31, 2.9 +/- 0.32 and 3.4 +/- 0.3 L at PEEP of 10, 20, and 30 cm of H2O, respectively (P < 0.05). Paralleling these changes, intrapulmonary shunt fraction decreased significantly (P < 0.05) from a control value of 12.9 +/- 0.5%, to 7.5 +/- 1.1 and 2.1 +/- 0.6%, at PEEP of 20 and 30 cm of H2O, respectively. Cardiac output was decreased by increasing values of PEEP, from control value of 11.7 +/- 1.56 L/min to 9.9 +/- 1.51, 8.8 +/- 1.33 and 5.62 +/- 0.56 L/min at PEEP of 10, 20, and 30 cm of H2O, respectively. Related to decreasing cardiac output, tissue oxygen delivery also decreased as PEEP was increased, from control value of 2.0 +/- 0.09 L/min to 1.8 +/- 0.07, 1.6 +/- 0.06, and 1.03 +/- 0.04 L/min at PEEP of 10, 20, and 30 cm of H2O, respectively. Thus, the effects of increasing values of PEEP in these ponies included increased functional residual capacity and arterial oxygenation, but marked reduction in cardiac output, resulting in no improvement or decrease in total oxygen delivery. Although PEEP is useful for improving arterial oxygenation, the deleterious cardiovascular effects should be anticipated or ameliorated by use of volume loading and/or inotrope administration.
Показать больше [+] Меньше [-]Increase in gene-transcript levels as indicators of up-regulation of the unfolded protein response in spontaneous canine tumors
2014
Elliot, Kirsten | MacDonald-Dickinson, Valerie | Linn, Kathleen | Simko, Elemir | Misra, Vikram
The unfolded protein response (UPR), a conserved cellular response to stressors such as hypoxia and nutrient deprivation, is associated with angiogenesis and metastasis in tumor cells. This article discusses a pilot study conducted to determine whether components of the UPR could be identified in spontaneous canine tumors and whether they were up-regulated within tumor tissue compared with adjacent normal tissue. Tissue samples of various spontaneous canine neoplasms were taken from 13 dogs shortly after surgical excision or euthanasia; control samples were taken from adjacent normal tissue. RNA purification and real-time quantitative reverse-transcription polymerase chain reaction were done to measure the expression of 4 genes associated with the UPR (HERP, CHOP, GRP78, and XBP1s). The results indicated that UPR gene expression can be identified in spontaneous canine tumors and that the UPR is up-regulated, as indicated by significantly increased expression of CHOP and GRP78 within the tumor.
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