scholarly journals Effects of Yiqi Tongyang on HCN4 Protein Phosphorylation in Damaged Rabbit Sinoatrial Node Cells

2016 ◽  
Vol 2016 ◽  
pp. 1-6
Author(s):  
Jinfeng Liu ◽  
Ruxiu Liu ◽  
Jie Peng ◽  
Yanli Wang

The hyperpolarization-activated cyclic nucleotide-gated cation channel (If) is closely associated with sinoatrial node pacing function. The present study aimed to investigate the molecular mechanisms involved in pacing function improvements of damaged sinoatrial node cells and the consequent treatment effects on sick sinus syndrome (SSS) after the use of Yiqi Tongyang. HCN4 channel protein expression and phosphorylation were measured by immunoblotting and fluorescent quantitation. After ischemia-reperfusion injury (model group), the HCN4 protein and the optical density (OD) of the phosphorylated HCN4 protein as well as intracellular PKA activity in the sinoatrial node cells decreased significantly. However, the OD values and PKA activity increased to different degrees after treatment with serum containing different doses of Yiqi Tongyang; in contrast, no significant improvement was seen in the control group compared to the model group. These findings demonstrated that the use of the traditional Chinese medicine Yiqi Tongyang could increase HCN4 protein expression and phosphorylation as well as PKA activity within sinoatrial node cells damaged by ischemia-reperfusion. The HCN4 protein is involved in theIf-related ion channel. Here, we speculated that these effects could be associated with upregulation of HCN4 protein phosphorylation, which consequently improved cell automaticity, increased heart rate, and had treatment effects on SSS.

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Yuuki Shimizu ◽  
Larry Barr ◽  
Travis Fields ◽  
John W Calvert

Background: DJ-1/Park7 is a ubiquitously expressed protein typically associated with the development of early onset Parkinson’s disease. Recent data suggests that it also plays a role in the cellular response to stress. Although much is known about DJ-1 in the brain, very little has been investigated in the heart. Here, we aimed to examine the underlying molecular mechanisms mediating the actions of DJ-1 in the heart following the onset of myocardial ischemia-reperfusion (I/R) injury. Methods and Results: Wild-type (WT) control and DJ-1 deficient (DJ-1 KO) mice were subjected to in vivo myocardial I/R injury. DJ-1 KO mice (n=9) displayed increased areas of infarction (%INF/LV or AAR: 30.2 vs 22.0%, 53.6 vs 39.0%, Troponin-I: 47.4 vs 19.9ng/ml, p<0.05 respectively) and worsened left ventricular function (LVEF: 43.7 vs 58.1%, p<0.001) when compared to WT mice (n=9), confirming a protective role for DJ-1 in the heart. In an effort to evaluate the potential mechanism(s) responsible for the increased injury in DJ-1 KO mice, we focused on SUMOylation, a post-translational modification process which regulates various aspects of protein function, including transcription, subcellular localization, DNA repair, and cell cycle. DJ-1 KO hearts after I/R injury were found to display enhanced accumulation of SUMO-1 modified proteins, (this modification is generally associated with cell injury), and reduced SUMO-2/3 modified proteins (this modification is generally associated with cytoprotection). Further analysis, revealed that the protein expression of the de-SUMOylation enzyme SENP-1 (removes SUMO-1 modifications) was reduced, whereas the expression of SENP-5 (removes SUMO-2/3 modifications) was enhanced in DJ-1 KO hearts after I/R injury. Changes in mRNA levels did not account for the altered protein expression of SENP-1 and SENP-5. So, we evaluated the direct interaction of DJ-1 with both proteins in hearts of WT mice following I/R using co-immunoprecipitation. We found that SENP1 binding with DJ-1 was down-regulated, whereas SENP5 binding with DJ-1 was up-regulated. Conclusion: Our data demonstrated that the activation of DJ-1 in response to myocardial I/R injury protects the heart by the modulation of SUMOylation via direct binding of SENP1 and SENP5.


2020 ◽  
Vol 98 (12) ◽  
pp. 855-860
Author(s):  
Yaping Zhang ◽  
Nan Ding ◽  
Hanlu Yi ◽  
Yudong Zhao ◽  
Zankai Ye ◽  
...  

The objective was to identify the differential expressed miRNA during cerebral ischemia–reperfusion injury (CIRI) process, thereby assisting in elucidating the mechanism of CIRI development and providing a potential target for CIRI prevention and treatment. Six mice were randomly assigned to two groups: control group and CIRI model group. A global cerebral IR model by four-vessel occlusion was prepared among the CIRI model group. Brain tissues were collected 48 h after reperfusion. Total RNA was extracted for each sample. miRNA microarrays were employed to detect the differentially expressed miRNA between the CIRI group and the control group. One differentially expressed miRNA was selected for verification by PCR. Compared with the control group, 69 miRNAs were significantly differential expressed in samples of the CIRI group, among which 50 miRNAs were upregulated and 19 miRNAs were downregulated. The real-time qPCR results indicated that the results of the miRNA microarray were reliable. A number of miRNAs were significantly regulated in the CIRI model, which suggested that miRNA was closely associated with the pathological alterations after ischemia. These identified miRNAs may provide directions and targets for the future pathological research of CIRI.


2020 ◽  
Vol 23 (3) ◽  
pp. 214-224 ◽  
Author(s):  
Esra Cakir ◽  
Ufuk Cakir ◽  
Cuneyt Tayman ◽  
Tugba Taskin Turkmenoglu ◽  
Ataman Gonel ◽  
...  

Background: Activated inflammation and oxidant stress during cerebral ischemia reperfusion injury (IRI) lead to brain damage. Astaxanthin (ASX) is a type of carotenoid with a strong antioxidant effect. Objective: The aim of this study was to investigate the role of ASX on brain IRI. Methods: A total of 42 adult male Sprague-Dawley rats were divided into 3 groups as control (n=14) group, IRI (n=14) group and IRI + ASX (n=14) group. Cerebral ischemia was instituted by occluding middle cerebral artery for 120 minutes and subsequently, reperfusion was performed for 48 hours. Oxidant parameter levels and protein degradation products were evaluated. Hippocampal and cortex cell apoptosis, neuronal cell count, neurological deficit score were evaluated. Results: In the IRI group, oxidant parameter levels and protein degradation products in the tissue were increased compared to control group. However, these values were significantly decreased in the IRI + ASX group (p<0.05). There was a significant decrease in hippocampal and cortex cell apoptosis and a significant increase in the number of neuronal cells in the IRI + ASX group compared to the IRI group alone (p<0.05). The neurological deficit score which was significantly lower in the IRI group compared to the control group was found to be significantly improved in the IRI + ASX group (p<0.05). Conclusion: Astaxanthin protects the brain from oxidative damage and reduces neuronal deficits due to IRI injury.


2020 ◽  
Vol 31 (4) ◽  
pp. 716-730 ◽  
Author(s):  
Marc Johnsen ◽  
Torsten Kubacki ◽  
Assa Yeroslaviz ◽  
Martin Richard Späth ◽  
Jannis Mörsdorf ◽  
...  

BackgroundAlthough AKI lacks effective therapeutic approaches, preventive strategies using preconditioning protocols, including caloric restriction and hypoxic preconditioning, have been shown to prevent injury in animal models. A better understanding of the molecular mechanisms that underlie the enhanced resistance to AKI conferred by such approaches is needed to facilitate clinical use. We hypothesized that these preconditioning strategies use similar pathways to augment cellular stress resistance.MethodsTo identify genes and pathways shared by caloric restriction and hypoxic preconditioning, we used RNA-sequencing transcriptome profiling to compare the transcriptional response with both modes of preconditioning in mice before and after renal ischemia-reperfusion injury.ResultsThe gene expression signatures induced by both preconditioning strategies involve distinct common genes and pathways that overlap significantly with the transcriptional changes observed after ischemia-reperfusion injury. These changes primarily affect oxidation-reduction processes and have a major effect on mitochondrial processes. We found that 16 of the genes differentially regulated by both modes of preconditioning were strongly correlated with clinical outcome; most of these genes had not previously been directly linked to AKI.ConclusionsThis comparative analysis of the gene expression signatures in preconditioning strategies shows overlapping patterns in caloric restriction and hypoxic preconditioning, pointing toward common molecular mechanisms. Our analysis identified a limited set of target genes not previously known to be associated with AKI; further study of their potential to provide the basis for novel preventive strategies is warranted. To allow for optimal interactive usability of the data by the kidney research community, we provide an online interface for user-defined interrogation of the gene expression datasets (http://shiny.cecad.uni-koeln.de:3838/IRaP/).


2021 ◽  
Vol 22 (4) ◽  
pp. 1864
Author(s):  
Norbert Nemeth ◽  
Katalin Peto ◽  
Zsuzsanna Magyar ◽  
Zoltan Klarik ◽  
Gabor Varga ◽  
...  

Hepatic ischemia-reperfusion injury (IRI) is a multifactorial phenomenon which has been associated with adverse clinical outcomes. IRI related tissue damage is characterized by various chronological events depending on the experimental model or clinical setting. Despite the fact that IRI research has been in the spotlight of scientific interest for over three decades with a significant and continuous increase in publication activity over the years and the large number of pharmacological and surgical therapeutic attempts introduced, not many of these strategies have made their way into everyday clinical practice. Furthermore, the pathomechanism of hepatic IRI has not been fully elucidated yet. In the complex process of the IRI, flow properties of blood are not neglectable. Hemorheological factors play an important role in determining tissue perfusion and orchestrating mechanical shear stress-dependent endothelial functions. Antioxidant and anti-inflammatory agents, ischemic conditioning protocols, dynamic organ preservation techniques may improve rheological properties of the post-reperfusion hepatic blood flow and target endothelial cells, exerting a potent protection against hepatic IRI. In this review paper we give a comprehensive overview of microcirculatory, rheological and molecular–pathophysiological aspects of hepatic circulation in the context of IRI and hepatoprotective approaches.


2020 ◽  
pp. 1-6
Author(s):  
JinRan Yang ◽  
Xinchang Li ◽  
Hua Yang ◽  
Chenmei Long

<b><i>Purpose:</i></b> The aim of this study was to investigate the therapeutic effect of oleanolic acid (OA) on the renal ischemia reperfusion injury (RIRI) and the possible mechanism. <b><i>Methods:</i></b> The RIRI model was successfully established in rats. OA, LY294002 (a PI3K inhibitor), and OA combined with LY294002 were dosed to rats in 3 therapeutic groups, respectively. The blood was collected to detect the concentration of Cr and BUN by ELISA. The kidney of each rat was collected to detect the concentration of renal injury factor (Kim-1) and the HE staining was performed. Western blot was used to detect the expression level of PI3K, p-AKT, AKT, PDK1, Skp2, and p27 in the renal tissue homogenate. <b><i>Results:</i></b> The symptom of vacuolar degeneration and interstitial edema was greatly improved in the rat kidney from the 3 therapeutic groups, compared with that from the RIRI model group. No significant difference was observed among the 3 therapeutic groups. The concentration of Cr in the 3 therapeutic groups was greatly lower than that in the RIRI model group. The expression level of p-AKT/AKT, PI3K, PDK1, Skp2, and p27 in OA group, LY294002 group, and OA combined with LY294002 group was significantly lower than that in the RIRI model group, respectively. <b><i>Conclusion:</i></b> OA could improve the symptom of RIRI, possibly by inhibiting PI3K/AKT signal pathway.


Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Jiefeng Xu ◽  
Sen Ye ◽  
Zilong Li ◽  
Moli Wang ◽  
Zhengquan Wang ◽  
...  

Introduction: Systemic ischemia-reperfusion injury produced by CA and resuscitation can result in severe post-cardiac arrest syndrome; which includes systemic inflammatory response and multiple organ dysfunction syndrome such as acute pulmonary edema. We previously demonstrated that remote ischemic post-conditioning (RIpostC) improved post-resuscitation myocardial and cerebral function in a rat model of CA. In this study, we investigated the effects of RIpostC on inflammatory response and pulmonary edema after CPR in a porcine model. Hypothesis: RIpostC would alleviate post-resuscitation inflammatory response and pulmonary edema in a porcine model of CA. Methods: Fourteen male domestic pigs weighing 37 ± 2 kg were utilized. Ventricular fibrillation was electrically induced and untreated for 10 mins. The animals were then randomized to receive RIpostC or control. Coincident with the start of CPR, RIpostC was induced by four cycles of 5 mins of limb ischemia and then 5 mins of reperfusion. Defibrillation was attempted after 5 mins of CPR. The resuscitated animals were monitored for 4 hrs and observed for an additional 68 hrs. Results: Six of the seven animals in each group were successfully resuscitated. After resuscitation, significantly lower levels of tumor necrosis factor-α and interleukin-6 were measured in the animals that received RIpostC when compared with the control group. Post-resuscitation extra-vascular lung water index was lower in the RIpostC group than in the control group; in which the differences were significant at 2,3 and 4 hrs (Table). Conclusion: In a porcine model of CA, RIpostC significantly alleviates post-resuscitation inflammatory response and pulmonary edema.


Hypertension ◽  
2021 ◽  
Vol 78 (Suppl_1) ◽  
Author(s):  
Yves Wang ◽  
Nhu Nguyen ◽  
Keith Nehrke ◽  
Paul S Brookes ◽  
Thu H Le

The glutathione S-transferase ( Gst ) gene family encodes antioxidant enzymes. In humans, a common null allele deletion variant of GST μ-1 ( GSTM1 ) is highly prevalent across populations and is associated with increased risk and progression of various diseases. Using a Gstm1 knockout (KO) mouse model, we previously showed that KO mice with angiotensin II-induced hypertension (HTN) have increased kidney injury compared to wild-type (WT) controls, mediated by elevated oxidative stress. In the same mouse model, we have recently reported that in a Langendorff-perfused cardiac ischemia-reperfusion injury (IRI) model, where damage is also mediated by oxidative stress, male KO hearts are protected while females are not. Here, we investigated the molecular mechanisms for this difference in male hearts. WT and KO mice of both sexes were studied at 12-20 weeks of age. Hearts were snap frozen at baseline and after 25 min of global ischemia, and kidneys were collected at baseline and 4 weeks following HTN induction. A panel of 18 Gst genes were probed by qPCR from baseline hearts and kidneys of both sexes. Global metabolites were assayed using Metabolon, Inc. from hearts of both sexes and kidneys of males, at both baseline and diseased states. Analysis by qPCR (n = 3/group) showed that male, but not female, KO hearts had upregulation of other Gst s. In contrast, no significant differences between were found in male kidneys. Metabolomics (n = 6/group) detected 695 metabolites in hearts and 926 in kidneys. There were increases in several metabolites in KO vs. WT hearts including those with antioxidant properties. Notably, increases in carnosine and anserine were observed in KO male hearts but not in female hearts, while that of other antioxidant-related metabolites were observed in hearts of both sexes, but not in kidneys. HTN induced significant increases in metabolites in KO vs. WT kidneys in the pathways related to and linking methionine, cysteine, and glutathione, which were not observed in hearts. In this study, gene expression and metabolites suggest that the mechanisms compensating for the loss of GSTM1 are both tissue and sex specific. The resulting differences in antioxidant enzymes and metabolites may explain the unexpected protection for male Gstm1 KO hearts in IRI.


2011 ◽  
Vol 26 (suppl 1) ◽  
pp. 14-20 ◽  
Author(s):  
Vilma Leite de Sousa Pires ◽  
José Reniclebson Feitosa de Souza ◽  
Sergio Botelho Guimarães ◽  
Antonio Ribeiro da Silva Filho ◽  
José Huygens Parente Garcia ◽  
...  

PURPOSE: To investigate the effect of L-alanyl-L-glutamine (L-Ala-Gln) preconditioning in an acute cerebral ischemia/reperfusion (I/R) model in gerbils. METHODS: Thirty-six Mongolian gerbils (Meriones unguiculatus), (60-100g), were randomized in 2 groups (n=18) and preconditioned with saline 2.0 ml (Group-S) or 0.75g/Kg of L-Ala-Gln, (Group-G) administered into the femoral vein 30 minutes prior to I/R. Each group was divided into three subgroups (n=6). Anesthetized animals (urethane, 1.5g/Kg, i.p.) were submitted to bilateral occlusion of common carotid arteries during 15 minutes. Samples (brain tissue and arterial blood) were collected at the end of ischemia (T0) and after 30 (T30) and 60 minutes (T60) for glucose, lactate, myeloperoxidase (MPO), thiobarbituric acid reactive substances (TBARS), glutathione (GSH) assays and histopathological evaluation. RESULTS: Glucose and lactate levels were not different in studied groups. However glycemia increased significantly in saline groups at the end of the reperfusion period. TBARS levels were significantly different, comparing treated (Group-G) and control group after 30 minutes of reperfusion (p<0.05) in cerebral tissue. Pretreatment with L-Ala-Gln promoted a significant increase in cerebral GSH contents in Group-G at T30 (p<0.001) time-point compared with Group-S. At T30 and T60, increased levels of GSH occurred in both time-points. There were no group differences regarding MPO levels. Pyknosis, presence of red neurons and intracellular edema were significantly smaller in Group-G. CONCLUSION: Preconditioning with L-Ala-Gln in gerbils submitted to cerebral ischemia/reperfusion reduces oxidative stress and degeneration of the nucleus (pyknosis) and cell death (red neurons) in the cerebral tissue.


2017 ◽  
Vol 11 (1-2) ◽  
pp. 19 ◽  
Author(s):  
Gokhun Ozmerdiven ◽  
Burhan Coskun ◽  
Onur Kaygisiz ◽  
Berna Aytac Vuruskan ◽  
Burak Asiltas ◽  
...  

Introduction: Nitric oxide (NO) plays an important role in the ischemia and reperfusion process. In this study, we aimed to examine the effect of L-arginine, tadalafil, and their combination for preventionof the ischemia reperfusion injury after testis torsion in rats.Methods: A total of 40 adult, male Sprague-Dawley rats were allocated into five groups. Three hours of left testicular torsion was performed in each group, excluding the control group. While the ischemia reperfusion (I/R) group had no treatment, I/R + Arg group received L-arginine, I/R + Td group received tadalafil and I/R + Arg + Td group received tadalafil and L-arginine 30 minutes before the detorsion. Then the left testis was untwisted for four hours of reperfusion. After bilateral orchiectomy, lipid peroxidation (LPx) and glutathione (GSH) activities were examined in testicular tissue.Spermatogenesis was evaluated with Johnsen’s score.Results: LPx levels of the I/R group were found to be significantly higher than for groups that received drugs for both testes (p<0.001). GSH levels of the combination group were higher than I/R group inipsilateral testis (p<0.01) and it was significantly higher than other groups for contralateral testis (p<0.001 for I/R group, p<0.01 for I/R + Arg, p<0.05 for I/R + Td). Mean Johnsen’s score of the I/Rgroup was found to be significantly lower than treatment groups in ipsilateral testis (p<0.001 for I/R + Arg + Td group, p<0.01 for other treatment goups) and contralateral testis (p<0.001). The meanJohnsen score of the combination group was significantly higher than that of other treatment groups in ipsilateral testis (p<0.05) and it was significantly higher than in the I/R + Td group in the contralateral testis (p<0.05).Conclusions: L-arginine, tadalafil, and combination of these two molecules showed protective effect against ischemia/reperfusion injury for both testes after unilateral testis torsion.


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