scholarly journals Prolonged Helium Postconditioning Protocols during Early Reperfusion Do Not Induce Cardioprotection in the Rat HeartIn Vivo: Role of Inflammatory Cytokines

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Gezina Tanya Mei Ling Oei ◽  
Hamid Aslami ◽  
Raphaela Priscilla Kerindongo ◽  
Renske Johanna Steenstra ◽  
Charlotte Jacqueline Peter Beurskens ◽  
...  

Postconditioning of myocardial tissue employs short cycles of ischemia or pharmacologic agents during early reperfusion. Effects of helium postconditioning protocols on infarct size and the ischemia/reperfusion-induced immune response were investigated by measurement of protein and mRNA levels of proinflammatory cytokines. Rats were anesthetized with S-ketamine (150 mg/kg) and diazepam (1.5 mg/kg). Regional myocardial ischemia/reperfusion was induced; additional groups inhaled 15, 30, or 60 min of 70% helium during reperfusion. Fifteen minutes of helium reduced infarct size from 43% in control to 21%, whereas 30 and 60 minutes of helium inhalation led to an infarct size of 47% and 39%, respectively. Increased protein levels of cytokine-induced neutrophil chemoattractant (CINC-3) and interleukin-1 beta (IL-1β) were found after 30 or 60 min of helium inhalation, in comparison to control. 30 min of helium increased mRNA levels of CINC-3, IL-1β, interleukin 6 (IL-6), and tumor necrosis factor alpha (TNF-α) in myocardial tissue not directly subjected to ischemia/reperfusion. These results suggest that the effectiveness of the helium postconditioning protocol is very sensitive to duration of noble gas application. Additionally, helium was associated with higher levels of inflammatory cytokines; however, it is not clear whether this is causative of nature or part of an epiphenomenon.

2021 ◽  
Vol 10 (9) ◽  
pp. 2020
Author(s):  
Fariba Rad ◽  
Ali Dabbagh ◽  
Akbar Dorgalaleh ◽  
Arijit Biswas

Coronavirus disease 2019 (COVID-19), with a broad range of clinical and laboratory findings, is currently the most prevalent medical challenge worldwide. In this disease, hypercoagulability and hyperinflammation, two common features, are accompanied by a higher rate of morbidity and mortality. We assessed the association between baseline inflammatory cytokine levels and coagulopathy and disease outcome in COVID-19. One hundred and thirty-seven consecutive patients hospitalized with COVID-19 were selected for the study. Baseline interleukin-1 (IL-1), IL-6, and tumor necrosis factor alpha (TNF-α) level were measured at time of admission. At the same time, baseline coagulation parameters were also assessed during the patient’s hospitalization. Clinical findings, including development of thrombosis and clinical outcome, were recorded prospectively. Out of 136 patients, 87 (~64%) had increased cytokine levels (one or more cytokines) or abnormal coagulation parameters. Among them, 58 (~67%) had only increased inflammatory cytokines, 12 (~14%) had only coagulation abnormalities, and 17 (19.5%) had concomitant abnormalities in both systems. It seems that a high level of inflammatory cytokines at admission points to an increased risk of developing coagulopathy, thrombotic events, even death, over the course of COVID-19. Early measurement of these cytokines, and timely co-administration of anti-inflammatories with anticoagulants could decrease thrombotic events and related fatal consequences.


Biomolecules ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1667
Author(s):  
Jian-Hong Lin ◽  
Kun-Ta Yang ◽  
Pei-Ching Ting ◽  
Yu-Po Luo ◽  
Ding-Jyun Lin ◽  
...  

Myocardial ischemia/reperfusion (I/R) injury has been associated with ferroptosis, which is characterized by an iron-dependent accumulation of lipid peroxide to lethal levels. Gossypol acetic acid (GAA), a natural product taken from the seeds of cotton plants, prevents oxidative stress. However, the effects of GAA on myocardial I/R-induced ferroptosis remain unclear. This study investigated the ability of GAA to attenuate I/R-induced ferroptosis in cardiomyocytes along with the underlying mechanisms in a well-established rat model of myocardial I/R and isolated neonatal rat cardiomyocytes. H9c2 cells and cardiomyocytes were treated with the ferroptosis inducers erastin, RSL3, and Fe-SP. GAA could protect H9c2 cells against ferroptotic cell death caused by these ferroptosis inducers by decreasing the production of malondialdehyde and reactive oxygen species, chelating iron content, and downregulating mRNA levels of Ptgs2. GAA could prevent oxygen-glucose deprivation/reperfusion-induced cell death and lipid peroxidation in the cardiomyocytes. Moreover, GAA significantly attenuated myocardial infarct size, reduced lipid peroxidation, decreased the mRNA levels of the ferroptosis markers Ptgs2 and Acsl4, decreased the protein levels of ACSL4 and NRF2, and increased the protein levels of GPX4 in I/R-induced ex vivo rat hearts. Thus, GAA may play a cytoprotectant role in ferroptosis-induced cardiomyocyte death and myocardial I/R-induced ferroptotic cell death.


2021 ◽  
Vol 19 (3) ◽  
pp. 467-476
Author(s):  
Jung-Soon Han

Purpose: This study investigated the nutritional value of Misutkaru with added Gryllus bimaculatus powder (GBM) and its applicability as a healthy functional food.Methods: Chemical analysis of the moisture, crude fat, protein, and mineral contents was performed in accordance with the Association of Official Analytical Chemists (AOAC) guidelines. The amino acid and fatty acid compositions were analyzed using an automatic amino acid analyzer and gas chromatography, respectively. The levels of inflammatory cytokines tumor necrosis factor‑alpha (TNF-α), interleukin 1 beta (IL-1β), and interleukin 6 (IL‑6) induced by lipopolysaccharides in RAW 264.7 cells were measured.Results: The general composition per 100 g of GBM was 41.87 g protein, 19.75 g fat, and 28.52 g carbohydrates. The mineral content per 100 g of GBM was 889.66 mg calcium, 1189.73 mg potassium, 220.36 mg magnesium, 207.51 mg sodium, 694.81 mg phosphorus, and 15.50 mg zinc. In particular, valine (21.361 mg/kg), leucine (29.180 mg/kg), and isoleucine (15.562 mg/kg) were abundant in GBM. GBM also effectively downregulated the production of the inflammatory cytokines TNF-α, IL-1β, and IL-6 in RAW 264.7 macrophages.Conclusion: Misutkaru with added Gryllus bimaculatus powder may have potential for application in the development of food materials or foods to prevent muscle loss in elderly individuals and sarcopenia patients, build muscle, and prevent increase in blood lipid concentrations in middle aged people. In particular, as Gryllus bimaculatus is low in fat and carbohydrates, it can be used as a diet material.


2015 ◽  
Vol 93 (4) ◽  
pp. 253-260 ◽  
Author(s):  
Yu Zhang ◽  
Ruhong Yan ◽  
Yae Hu

Oxymatrine (OMT) is the quinolizidine alkaloid extracted from the Chinese herb Sophora flavescens Ait. that has many pharmacological effects and is used for the treatment of some inflammatory diseases. In this study, RAW264.7 cells and THP-1 differentiated macrophages were pretreated with various concentrations of OMT at 2 h prior to treatment with lipopolysaccharide (LPS) (1.0 μg/mL) for different durations. We detected the anti-inflammatory effect of OMT in LPS-stimulated macrophages and investigated the molecular mechanism. We showed that OMT pretreatment significantly inhibited the LPS-induced secretion of nitric oxide (NO), interleukin-1 beta (IL-1β), and tumor necrosis factor-alpha (TNF-α) in supernatant, attenuated the mRNA levels of inducible nitric oxide synthase (iNOS), IL-1β, TNF-α, and Toll-like receptor 4 (TLR4), increased TLR4 and phosphorylation of inhibitor of kappa B-alpha (p-IBα) in cytosol, and decreased the nuclear level of nuclear factor-κB (NF-κB) p65 in macrophages. In conclusion, OMT exerts anti-inflammatory properties in LPS-stimulated macrophages by down-regulating the TLR4/NF-κB pathway.


2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Jimmy Zhang ◽  
Marcin K Karcz ◽  
Sergiy M Nadtochiy ◽  
Paul S Brookes

Background: To date, there are no FDA-approved therapies for the reduction of infarct size in acute myocardial infarction. Previously, we developed a cell-based phenotypic assay of ischemia-reperfusion (IR) injury, which was used to identify novel cytoprotective agents delivered prior to ischemia. Herein, we sought to identify cytoprotective agents in a more clinically relevant model: drug delivery at reperfusion, and to investigate possible underlying mechanisms of protection. Methods: Primary adult mouse cardiomyocytes were subjected to simulated IR injury using a modified Seahorse XF24 apparatus with drug addition at the onset of reperfusion. Cell death was estimated using LDH release. Drugs which protected cardiomyocytes in vitro were tested in a Langendorff model of IR injury, measuring functional recovery and infarct size. In separate experiments, metabolites extracted from perfused hearts were resolved by HPLC. Results: Nornicotine was identified as a cardioprotective agent in the screen. In perfused hearts, 10 nM nornicotine injected at the onset of reperfusion improved functional recovery and decreased in infarct size (13.1% ± 2.4 vs 49.2% ± 2.5 in non-treated hearts, p<0.05, n=16-20). Nornicotine also exhibited profound inhibitory effects on mitochondrial complex I activity. Succinate is known to accumulate in ischemia, and its rapid consumption during early reperfusion exacerbates reperfusion injury via ROS generation from electron backflow through complex I [PMID: 25383517]. In non-treated hearts, we confirmed that high post ischemic levels of succinate rapidly declined during the first 2 min of reperfusion. In contrast, nornicotine slowed post-ischemic succinate consumption, suggesting that electron backflow through complex I is the major pathway driving succinate consumption. Conclusions: Herein, we demonstrated that nornicotine was cardioprotective when delivered at early reperfusion in vitro and ex vivo. The mechanism of cardioprotection may be due to inhibition of rapid succinate consumption during early reperfusion via reverse electron flow back through complex I.


2018 ◽  
Vol 23 (5) ◽  
pp. 446-455 ◽  
Author(s):  
Oussama Bakhta ◽  
Simon Blanchard ◽  
Anne-Laure Guihot ◽  
Sophie Tamareille ◽  
Delphine Mirebeau-Prunier ◽  
...  

Background: Inflammation plays a crucial role in the pathophysiology of myocardial ischemia/reperfusion (I/R) injury. A clinical trial has recently reported a smaller infarct size in a cohort of patients with ST-segment elevation myocardial infarction (MI) treated with a short colchicine course. The mechanism underlying colchicine-induced cardioprotection in the early MI phase remains unclear. We hypothesized that a short pretreatment with colchicine could induce acute beneficial effects by protecting the heart against inflammation in myocardial I/R injury. Methods and Results: Rats were subjected to 40-minute left anterior descending coronary occlusion, followed by 120-minute reperfusion. Colchicine (0.3 mg/kg) or a vehicle was administered per os 24 hours and immediately before surgery. Infarct size was significantly reduced in the colchicine group (35.6% ± 3.0% vs 46.6% ± 3.3%, P < .05). The beneficial effects of colchicine were associated with an increased systemic interleukin-10 (IL-10) level and decreased cardiac transforming growth factor-β level. Interleukin-1β was found to increase in a “time of reperfusion”-dependent manner. Colchicine inhibited messenger RNA expression of caspase-1 and pro-IL-18. Interleukin-1β injected 10 minutes prior to myocardial ischemia induced greater infarct size (58.0% ± 2.0%, P < .05) as compared to the vehicle. Colchicine combined to IL-1β injection significantly decreased infarct size (47.1% ± 2.2%, P < .05) as compared to IL-1β alone, while colchicine alone exhibited a significantly more marked cardioprotective effect than the colchicine-IL-1β association. Conclusion: The cardioprotection induced by a short colchicine pretreatment was associated with an anti-inflammatory effect in the early reperfusion phase in our rat MI model.


2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
Ralf Erkens ◽  
Tatsiana Suvorava ◽  
Thomas R. Sutton ◽  
Bernadette O. Fernandez ◽  
Monika Mikus-Lelinska ◽  
...  

The transcription factor nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is a key master switch that controls the expression of antioxidant and cytoprotective enzymes, including enzymes catalyzing glutathione de novo synthesis. In this study, we aimed to analyze whether Nrf2 deficiency influences antioxidative capacity, redox state, NO metabolites, and outcome of myocardial ischemia reperfusion (I/R) injury. In Nrf2 knockout (Nrf2 KO) mice, we found elevated eNOS expression and preserved NO metabolite concentrations in the aorta and heart as compared to wild types (WT). Unexpectedly, Nrf2 KO mice have a smaller infarct size following myocardial ischemia/reperfusion injury than WT mice and show fully preserved left ventricular systolic function. Inhibition of NO synthesis at onset of ischemia and during early reperfusion increased myocardial damage and systolic dysfunction in Nrf2 KO mice, but not in WT mice. Consistent with this, infarct size and diastolic function were unaffected in eNOS knockout (eNOS KO) mice after ischemia/reperfusion. Taken together, these data suggest that eNOS upregulation under conditions of decreased antioxidant capacity might play an important role in cardioprotection against I/R. Due to the redundancy in cytoprotective mechanisms, this fundamental antioxidant property of eNOS is not evident upon acute NOS inhibition in WT mice or in eNOS KO mice until Nrf2-related signaling is abrogated.


1991 ◽  
Vol 261 (4) ◽  
pp. L315-L321 ◽  
Author(s):  
J. N. Allen ◽  
D. J. Herzyk ◽  
M. D. Wewers

To study the role of microtubules in cytokine production, the effect of the microtubule depolymerizing agent colchicine on lipopolysaccharide endotoxin (LPS)-induced interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) release by blood monocytes and alveolar macrophages were examined. Immunofluorescence microscopy demonstrated that LPS resulted in the appearance of microtubule-containing cytoplasmic appendages and that colchicine, which resulted in microtubule disruption in monocytes, blocked appendage formation. Colchicine resulted in approximately 50% increase in LPS-induced IL-1 beta release and a 50% decrease in LPS-induced TNF-alpha release by human monocytes at all doses of LPS tested. Although colchicine resulted in a statistically significant increase in LPS-stimulated human alveolar macrophage IL-1 beta release, the increase was not as great as that observed with monocytes. Northern blot analysis suggested that the colchicine effect occurs pretranslationally because colchicine caused an increase in LPS-stimulated IL-1 beta mRNA levels and a decrease in TNF-alpha mRNA levels. These results suggest that microtubules contribute to the regulation of endotoxin-stimulated mononuclear phagocyte cytokine production and that this regulation differs significantly between IL-1 beta and TNF-alpha.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1633-1633
Author(s):  
Tahereh Ghaziani ◽  
Ying Shan ◽  
Richard W. Lambrecht ◽  
Herbert L. Bonkovsky

Abstract Background: Heme oxygenase-1 (HO-1) is an antioxidant defense enzyme that converts toxic heme into antioxidants. HO-1 is strongly up-regulated by its physiologic substrate, heme, which is currently the treatment of choice for acute attacks of porphyria and which may have other therapeutic uses, as well (e.g., for cytoprotection or amelioration of ischemia/reperfusion injury by increasing supply of carbon monoxide, biliverdin, or bilirubin). Up-regulation of HO-1 expression has been associated with increased resistance to tissue injury. Bach1 is a bZip protein which forms heterodimers with small Maf proteins. HO-1 is expressed at higher levels in tissues of Bach1-deficient mice, indicating that Bach1 acts as a negative regulator of the mouse HO-1 gene. The molecular mechanism that confers repression of HO-1 by Bach1, and whether there are similar effects in human cells, has remained elusive. The aim of this study was to assess whether modulation of human hepatic Bach1 expression by siRNA technology influences HO-1 gene expression and whether such gene silencing would enhance the inducing effects of heme on HO-1. Methods: siRNAs targeted 4 different positions of human Bach1 mRNA were designed and synthesized. We transfected Bach1-siRNA (25–200 nM) into Huh-7 cells using Lipofectamine for 24–72 h, after which, cells were treated with or without heme. We quantified HO-1 and Bach1 mRNA and protein levels by quantitative RT-PCR and western blotting, respectively. Effects and specificity of Bach1-siRNA were analyzed and compared with those of non-Bach1 related siRNAs (non-specific control-duplex (NSCD) and LaminB2-siRNA). Results: Bach1-siRNAs (25–200 nM) transfected into Huh-7 cells for 24–72 h significantly reduced Bach1 mRNA and protein levels approximately 80%, compared with non siRNA treated cells. In contrast, transfection with same amounts of NSCD or LaminB2 siRNA did not reduce Bach1 mRNA or protein levels, confirming the specificity of Bach1-siRNA in Huh-7 cells. A significant finding of these studies was the 7-fold up-regulation of the HO-1 gene in Bach1-siRNA transfected cells, compared to cells without Bach1-siRNA or those transfected with NSCD or LaminB2. Bach1, NSCD, and LaminB2 siRNAs had no effect on HO-2 or 5-aminolevulinate synthase-1 mRNA levels (two genes that are not induced by heme). The effects of increasing concentrations of heme (up to 10 μM) in the presence or absence of Bach1-siRNA on the levels of HO-1 mRNA expression are shown in the Figure. For all of the heme concentrations tested, the levels of HO-1 mRNA were greater when Bach1 siRNA was present. Conclusions: Bach1 has a specific and selective effect to repress expression of human hepatic HO-1. Silencing of the Bach1 gene by siRNAs may be a useful method for up-regulating HO-1 gene expression. The combination of intravenous heme and Bach1 silencing may be useful for therapy of acute porphyrias in relapse or other conditions in which up-regulation of HO-1 may be beneficial. (Supported by grants from NIH [DK38825] and Ovation Pharmaceuticals, Inc.) Figure Figure


2019 ◽  
Vol 7 (4) ◽  
pp. 310-321
Author(s):  
Huang Xiang ◽  
Stampf Wael

Interleukin-1 (IL-1) is a central mediator of innate immunity and inflammation. IL-37 (IL-37), a newly described member of the IL-1 family, functions as a fundamental inhibitor of innate inflammation and immunity. The purpose of the present study was to determine the effects of interleukin-37 on neuron cells and on brain inflammation induced by brain ischemia/reperfusion (I/R). A transgenic mouse strain was generated to express human IL-37 (hIL-37Tg) and WT mice were subjected to (60 min) brain ischemia and followed by reperfusion (24 h), by using a mice model of transient focal cerebral ischemia induced by advancing a nylon mono-filament to occlude the middle cerebral artery (MCA). Infarct size was determined by triphenyltetrazolium chloride staining. The morphology of neurons in brain sections were examined by Nissl staining and cytokines/chemokines measured by ELIZA. IL-37Tg significantly reduced infarct size by 65.4% (P<0.05) compared with WT after I/R. Reduced inflammation was associated with decreased leukocyte recruitment, and reduced release of IL-1β and TNFα, macrophage inflammatory protein-2 (MIP-2), MCP-1 and keratinocyte chemokine (KC) compared with WT (P<0.05), whereas IL-10 was increased eight fold (P<0.05). IL-37 significantly reduced cell death and increased Bcl-2 expression in neurons. Thus, IL-37 emerges as a key modulator of brain inflammation and has important translational implications for both the prevention and treatment of patients suffering from brain ischemia.


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