scholarly journals Mechanistic Insight of Na/K-ATPase Signaling and HO-1 into Models of Obesity and Nonalcoholic Steatohepatitis

2019 ◽  
Vol 21 (1) ◽  
pp. 87 ◽  
Author(s):  
Rebecca Pratt ◽  
Hari Vishal Lakhani ◽  
Mishghan Zehra ◽  
Rutmann Desauguste ◽  
Sneha S. Pillai ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Nonalcoholic Steatohepatitis ◽  
Redox Regulation ◽  
Molecular Mechanisms ◽  
Antioxidant Properties ◽  
Molecular Targets ◽  
Heme Oxygenase 1 ◽  
Src Signaling ◽  
Amplification Loop ◽  
Pathophysiological Condition

Obesity is a multifaceted pathophysiological condition that has been associated with lipid accumulation, adipocyte dysfunction, impaired mitochondrial biogenesis and an altered metabolic profile. Redox imbalance and excessive release of inflammatory mediators have been intricately linked in obesity-associated phenotypes. Hence, understanding the mechanisms of redox signaling pathways and molecular targets exacerbating oxidative stress is crucial in improving health outcomes. The activation of Na/K-ATPase/Src signaling, and its downstream pathways, by reactive oxygen species (ROS) has been recently implicated in obesity and subsequent nonalcoholic steatohepatitis (NASH), which causes further production of ROS creating an oxidant amplification loop. Apart from that, numerous studies have also characterized antioxidant properties of heme oxygenase 1 (HO-1), which is suppressed in an obese state. The induction of HO-1 restores cellular redox processes, which contributes to inhibition of the toxic milieu. The novelty of these independent mechanisms presents a unique opportunity to unravel their potential as molecular targets for redox regulation in obesity and NASH. The attenuation of oxidative stress, by understanding the underlying molecular mechanisms and associated mediators, with a targeted treatment modality may provide for improved therapeutic options to combat clinical disorders.

Abstract MP58: Tissue And Sex Specific Effects Of Gstm1 Deletion In Mouse Models

Hypertension ◽  
2021 ◽  
Vol 78 (Suppl_1) ◽  
Author(s):  
Yves Wang ◽  
Nhu Nguyen ◽  
Keith Nehrke ◽  
Paul S Brookes ◽  
Thu H Le
Keyword(s):  
Oxidative Stress ◽  
Antioxidant Enzymes ◽  
Mouse Model ◽  
Molecular Mechanisms ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Antioxidant Properties ◽  
Iri Model ◽  
Increased Risk ◽  
Study Gene Expression

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.

scholarly journals Ginsenoside Rg1 Protects Cardiomyocytes Against Hypoxia/Reoxygenation Injury via Activation of Nrf2/HO-1 Signaling and Inhibition of JNK

2017 ◽  
Vol 44 (1) ◽  
pp. 21-37 ◽  
Author(s):  
Qianhui Li ◽  
Yin Xiang ◽  
Yu Chen ◽  
Yong Tang ◽  
Yachen Zhang
Keyword(s):  
Oxidative Stress ◽  
Antioxidant Properties ◽  
Heme Oxygenase 1 ◽  
Related Factor ◽  
Dependent Manner ◽  
Ginsenoside Rg1 ◽  
H9c2 Cells ◽  
Stress Injury ◽  
Mitochondrial Membrane Depolarization ◽  
Hypoxia Reoxygenation

Background/Aims: Excessive reactive oxygen species (ROS) disturb the physiology of H9c2 cells, which is regarded as a major cause of H9c2 cardiomyocyte apoptosis. Ginsenoside Rg1 is the main active extract of ginseng, which has important antioxidant properties in various cell models. This project investigated the role of ginsenoside Rg1 in hypoxia/reoxygenation (H/R)-induced oxidative stress injury in cultured H9c2 cells to reveal the underlying signaling pathways. Methods: H9c2 cells were pretreated with ginsenoside Rg1 for 12 h before exposure to H/R. In the absence or presence of Nrf2siRNA, HO-1 inhibitor (ZnPP-IX), and inhibitors of the MAPK pathway (SB203580, PD98059, SP600125), H9c2 cells were subjected to H/R with Rg1 treatment. The effects and mechanisms of H/R-induced cardiomyocyte injury were measured. Results: Ginsenoside Rg1 treatment suppressed H/R-induced apoptosis and caspase-3 activation. Ginsenoside Rg1 treatment decreased ROS production and mitochondrial membrane depolarization by elevating the intracellular antioxidant capacity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and reduced glutathione (GSH). Furthermore, ginsenoside Rg1 stimulation appeared to result in nuclear translocation of NF-E2-related factor 2 (Nrf2), along with enhanced expression of the downstream target gene heme oxygenase-1 (HO-1) in a dose-dependent manner. However, ginsenoside Rg1-mediated cardioprotection was abolished by Nrf2-siRNA and HO-1 inhibitor. H/R treatment increased the levels of phosphorylated c-Jun N-terminal kinases (p-JNK), which was dramatically attenuated by ginsenoside Rg1 and SP600125 (a specific JNK inhibitor). Conclusion: These observations indicate that ginsenoside Rg1 activates the Nrf2/HO-1 axis and inhibits the JNK pathway in H9c2 cells to protect against oxidative stress.

scholarly journals Biochemical Evaluation of the Antioxidant Effects of Hydroxytyrosol on Pancreatitis-Associated Gut Injury

Antioxidants ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 781 ◽  
Author(s):  
Roberta Fusco ◽  
Marika Cordaro ◽  
Rosalba Siracusa ◽  
Ramona D’Amico ◽  
Tiziana Genovese ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Interleukin 1 ◽  
Antioxidant Properties ◽  
Pancreatic Tissue ◽  
Intercellular Adhesion Molecule ◽  
Heme Oxygenase 1 ◽  
Related Factor ◽  
Intercellular Adhesion Molecule 1 ◽  
Colon Tissue ◽  
Necrosis Factor Alpha

Acute pancreatitis is a severe abdominal pathology often associated with several complications including gut dysfunction. Oxidative stress is one of the most important pathways involved in this pathology. Hydroxytyrosol (HT), a phenolic compound obtained from olive oil, has shown anti-inflammatory and antioxidant properties. We evaluated the effects of HT administration on pancreatic and intestinal injury induced by caerulein administration. CD1 female mice were administered caerulein (50 μg/kg) for 10 h. HT treatment (5 mg/kg) was performed 30 min after the first caerulein injection and for two consecutive hours afterwards. One hour after the last caerulein injection, mice were sacrificed and serum, colon and pancreatic tissue samples were collected. HT was able to reduce the serum hallmarks of pancreatitis (amylase and lipase), histological damage score in both pancreas and colon tissue, inflammatory cells recruitment (mast cells) in both injured tissues, intrapancreatic trypsin activity and overexpression of the adhesion molecules (Intercellular Adhesion Molecule-1 (ICAM-1) and P-selectin) in colon. Additionally, HT reduced cytokine (interleukin 1 beta (IL- 1β), interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α)) levels in serum, pancreas and colon tissue and chemokine release (monocyte chemotactic protein-1 (MCP1/CCL2)) in pancreas and colon tissue. HT decreased lipid peroxidation and oxidative stress (superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione S-transferase (GST) activity) by enhancing the nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) in both injured tissues. Moreover, HT preserved intestinal barrier integrity, as shown by the diamine oxidase (DAO) serum levels and tight junction (zonula occludens (ZO) and occludin) expression in pancreas and colon. Our findings demonstrated that HT would be an important therapeutic tool against pancreatitis-induced injuries in the pancreas and gut.

scholarly journals Effect of Blueberry Anthocyanins Malvidin and Glycosides on the Antioxidant Properties in Endothelial Cells

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Wuyang Huang ◽  
Yunming Zhu ◽  
Chunyang Li ◽  
Zhongquan Sui ◽  
Weihong Min
Keyword(s):  
Oxidative Stress ◽  
Reactive Oxygen Species ◽  
Endothelial Cells ◽  
Functional Food ◽  
Functional Role ◽  
Antioxidant Properties ◽  
Heme Oxygenase 1 ◽  
Oxygen Species ◽  
Good Resource

The objective of this research was to survey the antioxidant functional role of the main anthocyanins of blueberries in endothelial cells. Changes on the reactive oxygen species (ROS), xanthine oxidase-1 (XO-1), superoxide dismutase (SOD), and heme oxygenase-1 (HO-1) in cells of malvidin and the two glycosides were investigated. The results showed that these anthocyanins decreased the levels of ROS and XO-1 but increased the levels of SOD and HO-1. Glycosides improved the antioxidant capacity of malvidin to a great extent. The changes in the antioxidant properties of malvidin-3-glucoside were more pronounced than malvidin-3-galactoside. Variation in levels of malvidin-3-glucoside and malvidin-3-galactoside had a significant impact on antioxidant properties to different extents. It indicates that blueberries are a good resource of anthocyanins, which can protect cells from oxidative deterioration and use blueberry as a potential functional food to prevent diseases related to oxidative stress.

scholarly journals Antioxidant and Signal-Modulating Effects of Brown Seaweed-Derived Compounds against Oxidative Stress-Associated Pathology

2021 ◽  
Vol 2021 ◽  
pp. 1-22
Author(s):  
Rahima Begum ◽  
Saurav Howlader ◽  
A. N. M. Mamun-Or-Rashid ◽  
S. M. Rafiquzzaman ◽  
Ghulam Md Ashraf ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Bioactive Compounds ◽  
Molecular Mechanisms ◽  
Metabolic Diseases ◽  
Antioxidant Properties ◽  
Brown Seaweed ◽  
Sulfated Polysaccharide ◽  
Bioactive Substances ◽  
Brown Seaweeds ◽  
Therapeutic Properties

The biological and therapeutic properties of seaweeds have already been well known. Several studies showed that among the various natural marine sources of antioxidants, seaweeds have become a potential source of antioxidants because of their bioactive compounds. Most of the metabolic diseases are caused by oxidative stress. It is very well known that antioxidants have a pivotal role in the treatment of those diseases. Recent researches have revealed the potential activity of seaweeds as complementary medicine, which have therapeutic properties for health and disease management. Among the seaweeds, brown seaweeds (Phaeophyta) and their derived bioactive substances showed excellent antioxidant properties than other seaweeds. This review focuses on brown seaweeds and their derived major bioactive compounds such as sulfated polysaccharide, polyphenol, carotenoid, and sterol antioxidant effects and molecular mechanisms in the case of the oxidative stress-originated disease. Antioxidants have a potential role in the modification of stress-induced signaling pathways along with the activation of the oxidative defensive pathways. This review would help to provide the basis for further studies to researchers on the potential antioxidant role in the field of medical health care and future drug development.

Pleiotropic roles of melatonin against oxidative stress mediated tissue injury in the gastrointestinal tract: An overview

2019 ◽  
Vol 2 (2) ◽  
pp. 158-184 ◽  
Author(s):  
Palash K Pal ◽  
Bharati Bhattacharjee ◽  
Aindrila Chattopadhyay ◽  
Debasish Bandyopadhyay
Keyword(s):  
Oxidative Stress ◽  
Molecular Mechanisms ◽  
Clinical Symptoms ◽  
Tissue Injury ◽  
Ischemia Reperfusion ◽  
Antioxidant Properties ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Gi Tract ◽  
Pathological Conditions

The excessive production of free radicals and/or reactive oxygen species (ROS) in gastrointestinal (GI) tract leads to oxidative damages in GI tissues with development of varied pathological conditions and clinical symptoms. Many endogenous as well as exogenous factors are involved in such pathogenesis, herein, focus was given to the factors of metal toxicity, non-steroidal anti-inflammatory drugs (NSAIDs), ischemia-reperfusion, consumption of high fat diet and alcohol, and different pathological conditions and diseases. Since ROS is more or less involved in the GI damages caused by these factors, therefore attempts have been made to develop appropriate therapeutic agents that possess antioxidant properties. Being a potent antioxidant and free radical scavenger, melatonin was suggested as a potent therapeutic answer to these GI damages. The discovery of different binding sites and receptors of melatonin in the GI tissues further proves its local actions to protect these tissues from oxidative stress.  In the review, we attempt to try our best to summarize the current developments regarding the GI injuries caused by oxidative stress and the potential beneficial effects of melatonin on these injuries. The important molecular mechanisms associated with these changes were also highlighted in the discussion. We hope that this review will provide valuable information to consider melatonin as a suitable molecule used for GI tract protection.

scholarly journals Micro-RNA 21 inhibition of SMAD7 enhances fibrogenesis via leptin-mediated NADPH oxidase in experimental and human nonalcoholic steatohepatitis

2015 ◽  
Vol 308 (4) ◽  
pp. G298-G312 ◽  
Author(s):  
Diptadip Dattaroy ◽  
Sahar Pourhoseini ◽  
Suvarthi Das ◽  
Firas Alhasson ◽  
Ratanesh Kumar Seth ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Nadph Oxidase ◽  
Nonalcoholic Steatohepatitis ◽  
Molecular Mechanisms ◽  
Transforming Growth Factor ◽  
Micro Rna ◽  
Protein Levels ◽  
Significant Research ◽  
Human Livers

Hepatic fibrosis in nonalcoholic steatohepatitis (NASH) is the common pathophysiological process resulting from chronic liver inflammation and oxidative stress. Although significant research has been carried out on the role of leptin-induced NADPH oxidase in fibrogenesis, the molecular mechanisms that connect the leptin-NADPH oxidase axis in upregulation of transforming growth factor (TGF)-β signaling have been unclear. We aimed to investigate the role of leptin-mediated upregulation of NADPH oxidase and its subsequent induction of micro-RNA 21 (miR21) in fibrogenesis. Human NASH livers and a high-fat (60% kcal) diet-fed chronic mouse model, where hepatotoxin bromodichloromethane was used to induce NASH, were used for this study. To prove the role of the leptin-NADPH oxidase-miR21 axis, mice deficient in genes for leptin, p47phox, and miR21 were used. Results showed that wild-type mice and human livers with NASH had increased oxidative stress, increased p47phox expression, augmented NF-κB activation, and increased miR21 levels. These mice and human livers showed increased TGF-β, SMAD2/3-SMAD4 colocalizations in the nucleus, increased immunoreactivity against Col1α, and α-SMA with a concomitant decrease in protein levels of SMAD7. Mice that were deficient in leptin or p47phox had decreased activated NF-κB and miR21 levels, suggesting the role of leptin and NADPH oxidase in inducing NF-κB-mediated miR21 expression. Further miR21 knockout mice had decreased colocalization events of SMAD2/3-SMAD4 in the nucleus, increased SMAD7 levels, and decreased fibrogenesis. Taken together, the studies show the novel role of leptin-NADPH oxidase induction of miR21 as a key regulator of TGF-β signaling and fibrogenesis in experimental and human NASH.

scholarly journals Purinergic receptor X7 is a key modulator of metabolic oxidative stress-mediated autophagy and inflammation in experimental nonalcoholic steatohepatitis

2013 ◽  
Vol 305 (12) ◽  
pp. G950-G963 ◽  
Author(s):  
Suvarthi Das ◽  
Ratanesh Kumar Seth ◽  
Ashutosh Kumar ◽  
Maria B. Kadiiska ◽  
Gregory Michelotti ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Nonalcoholic Steatohepatitis ◽  
P2x7 Receptor ◽  
Molecular Mechanisms ◽  
Purinergic Receptor ◽  
Receptor Gene ◽  
Receptor Expression ◽  
Histopathological Analysis ◽  
Protein Levels ◽  
Metabolic Oxidative Stress

Recent studies indicate that metabolic oxidative stress, autophagy, and inflammation are hallmarks of nonalcoholic steatohepatitis (NASH) progression. However, the molecular mechanisms that link these important events in NASH remain unclear. In this study, we investigated the mechanistic role of purinergic receptor X7 (P2X7) in modulating autophagy and resultant inflammation in NASH in response to metabolic oxidative stress. The study uses two rodent models of NASH. In one of them, a CYP2E1 substrate bromodichloromethane is used to induce metabolic oxidative stress and NASH. Methyl choline-deficient diet feeding is used for the other NASH model. CYP2E1 and P2X7 receptor gene-deleted mice are used to establish their roles in regulating metabolic oxidative stress and autophagy. Autophagy gene expression, protein levels, confocal microscopy based-immunolocalization of lysosome-associated membrane protein (LAMP)2A and histopathological analysis were performed. CYP2E1-dependent metabolic oxidative stress induced increases in P2X7 receptor expression and chaperone-mediated autophagy markers LAMP2A and heat shock cognate 70 but caused depletion of light chain 3 isoform B (LC3B) protein levels. P2X7 receptor gene deletion significantly decreased LAMP2A and inflammatory indicators while significantly increasing LC3B protein levels compared with wild-type mice treated with bromodichloromethane. P2X7 receptor-deleted mice were also protected from NASH pathology as evidenced by decreased inflammation and fibrosis. Our studies establish that P2X7 receptor is a key regulator of autophagy induced by metabolic oxidative stress in NASH, thereby modulating hepatic inflammation. Furthermore, our findings presented here form a basis for P2X7 receptor as a potential therapeutic target in the treatment for NASH.

scholarly journals P2X7 Receptor as a Key Player in Oxidative Stress-Driven Cell Fate in Nonalcoholic Steatohepatitis

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Saurabh Chatterjee ◽  
Suvarthi Das
Keyword(s):  
Oxidative Stress ◽  
Nonalcoholic Steatohepatitis ◽  
Purinergic Receptors ◽  
Molecular Mechanisms ◽  
Inflammatory Responses ◽  
Purinergic Receptor ◽  
Leptin Resistance ◽  
Hepatocellular Injury ◽  
Cardiometabolic Disorders

Incidences of nonalcoholic fatty liver disease parallels increase in the global obesity epidemic. NAFLD has been shown to be associated with risks of cardiometabolic disorders and kidney disturbances. It is accompanied by insulin and leptin resistance that complicate the diagnosis and treatment of this public health menace. Though significant research is underway for understanding the molecular mechanisms of NAFLD and its subsequent inflammatory and fibrotic manifestations like nonalcoholic steatohepatitis, the role of purinergic receptors has been unclear. It is increasingly being recognized that damage associated molecular patterns like NAD and ATP that are released from injured cells via hepatocellular injury either by oxidative stress or lipotoxicity from steatosis activate the purinergic receptor. Based on evidence from inflammatory responses in the airways and vasculature and autoimmune complications in humans and rodents, it is beyond doubt that hepatocellular inflammation such as that seen in NASH can result from the activation of purinergic receptors. This event can result in the formation of inflammasomes and can be an important pathway for the progression of NASH. The present review evaluates the current knowledge of the role of oxidative stress and its signaling via P2X7 receptors in hepatocellular injury that might contribute to the NASH pathophysiology.

Knockdown of metallothionein 1 and 2 does not affect atrophy or oxidant activity in a novel in vitro model

2010 ◽  
Vol 109 (5) ◽  
pp. 1515-1523 ◽  
Author(s):  
Robert D. Hyldahl ◽  
Kevin S. O'Fallon ◽  
Lawrence M. Schwartz ◽  
Priscilla M. Clarkson
Keyword(s):  
Oxidative Stress ◽  
Muscle Atrophy ◽  
Molecular Mechanisms ◽  
Antioxidant Properties ◽  
Muscle Size ◽  
Skeletal Muscle Atrophy ◽  
Vitro Model ◽  
Serum Reduction ◽  
And Function

Skeletal muscle atrophy is a significant health problem that results in decreased muscle size and function and has been associated with increases in oxidative stress. The molecular mechanisms that regulate muscle atrophy, however, are largely unknown. The metallothioneins (MT), a family of genes with antioxidant properties, have been found to be consistently upregulated during muscle atrophy, although their function during muscle atrophy is unknown. Therefore, we hypothesized that MT knockdown would result in greater oxidative stress and an enhanced atrophy response in C2C12 myotubes subjected to serum reduction (SR), a novel atrophy-inducing stimulus. Forty-eight hours before SR, myotubes were transfected with small interfering RNA (siRNA) sequences designed to decrease MT expression. Muscle atrophy and oxidative stress were then measured at baseline and for 72 h following SR. Muscle atrophy was quantified by immunocytochemistry and myotube diameter measurements. Oxidative stress was measured using the fluorescent probe 5-(and-6)-carboxy-2′,7′-dichlorodihydrofluorescein. SR resulted in a significant increase in oxidative stress and a decrease in myotube size and protein content. However, there were no differences observed in the extent of muscle atrophy or oxidant activity following MT knockdown. We therefore conclude that the novel SR model results in a strong atrophy response and an increase in oxidant activity in cultured myotubes and that knockdown of MT does not affect that response.

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