scholarly journals Involvement of Oxidative and Endoplasmic Reticulum Stress in RDH12-Related Retinopathies

2021 ◽  
Vol 22 (16) ◽  
pp. 8863
Author(s):  
Hajrah Sarkar ◽  
Maria Toms ◽  
Mariya Moosajee
Keyword(s):  
Oxidative Stress ◽  
Endoplasmic Reticulum ◽  
Er Stress ◽  
Cell Lines ◽  
Retinol Dehydrogenase ◽  
Hek 293 ◽  
Transmission Electron ◽  
Key Pathways ◽  
And Oxidative Stress ◽  
Potential Therapeutics

Retinol dehydrogenase 12 (RDH12) is expressed in photoreceptor inner segments and catalyses the reduction of all-trans retinal (atRAL) to all-trans retinol (atROL), as part of the visual cycle. Mutations in RDH12 are primarily associated with autosomal recessive Leber congenital amaurosis. To further our understanding of the disease mechanisms, HEK-293 cell lines expressing wildtype (WT) and mutant RDH12 were created. The WT cells afforded protection from atRAL-induced toxicity and oxidative stress. Mutant RDH12 cells displayed reduced protein expression and activity, with an inability to protect cells from atRAL toxicity, inducing oxidative and endoplasmic reticulum (ER) stress, with upregulation of sXBP1, CHOP, and ATF4. Pregabalin, a retinal scavenger, attenuated atRAL-induced ER stress in the mutant RDH12 cell lines. A zebrafish rdh12 mutant model (rdh12u533 c.17_23del; p.(Val6AlafsTer5)) was generated through CRISPR-Cas9 gene editing. Mutant fish showed disrupted phagocytosis through transmission electron microscopy, with increased phagosome size at 12 months post-fertilisation. Rhodopsin mislocalisation and reduced expression of atg12 and sod2 indicated early signs of a rod-predominant degeneration. A lack of functional RDH12 results in ER and oxidative stress representing key pathways to be targeted for potential therapeutics.

scholarly journals Coptisine Attenuates Diabetes—Associated Endothelial Dysfunction through Inhibition of Endoplasmic Reticulum Stress and Oxidative Stress

Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4210
Author(s):  
Yan Zhou ◽  
Chunxiu Zhou ◽  
Xutao Zhang ◽  
Chi Teng Vong ◽  
Yitao Wang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Risk Factors ◽  
Endoplasmic Reticulum ◽  
Er Stress ◽  
Vascular Function ◽  
Inflammatory Responses ◽  
Therapeutic Potential ◽  
Ex Vivo ◽  
Diabetic Mice ◽  
And Oxidative Stress

Coptisine is the major bioactive protoberberine alkaloid found in Rhizoma Coptidis. Coptisine reduces inflammatory responses and improves glucose tolerance; nevertheless, whether coptisine has vasoprotective effect in diabetes is not fully characterized. Conduit arteries including aortas and carotid arteries were obtained from male C57BL/6J mice for ex vivo treatment with risk factors (high glucose or tunicamycin) and coptisine. Some arterial rings were obtained from diabetic mice, which were induced by high-fat diet (45% kcal% fat) feeding for 6 weeks combined with a low-dose intraperitoneal injection of streptozotocin (120 mg/kg). Functional studies showed that coptisine protected endothelium-dependent relaxation in aortas against risk factors and from diabetic mice. Coptisine increased phosphorylations of AMPK and eNOS and downregulated the endoplasmic reticulum (ER) stress markers as determined by Western blotting. Coptisine elevates NO bioavailability and decreases reactive oxygen species level. The results indicate that coptisine improves vascular function in diabetes through suppression of ER stress and oxidative stress, implying the therapeutic potential of coptisine to treat diabetic vasculopathy.

scholarly journals Crosstalk between endoplasmic reticulum stress and oxidative stress: a dynamic duo in multiple myeloma

2021 ◽  
Author(s):  
Sinan Xiong ◽  
Wee-Joo Chng ◽  
Jianbiao Zhou
Keyword(s):  
Oxidative Stress ◽  
Multiple Myeloma ◽  
Endoplasmic Reticulum ◽  
Er Stress ◽  
Cell Fate ◽  
Stress Responses ◽  
Plasma Cells ◽  
Reactive Oxygen Species Generation ◽  
Future Research ◽  
And Oxidative Stress

AbstractUnder physiological and pathological conditions, cells activate the unfolded protein response (UPR) to deal with the accumulation of unfolded or misfolded proteins in the endoplasmic reticulum. Multiple myeloma (MM) is a hematological malignancy arising from immunoglobulin-secreting plasma cells. MM cells are subject to continual ER stress and highly dependent on the UPR signaling activation due to overproduction of paraproteins. Mounting evidence suggests the close linkage between ER stress and oxidative stress, demonstrated by overlapping signaling pathways and inter-organelle communication pivotal to cell fate decision. Imbalance of intracellular homeostasis can lead to deranged control of cellular functions and engage apoptosis due to mutual activation between ER stress and reactive oxygen species generation through a self-perpetuating cycle. Here, we present accumulating evidence showing the interactive roles of redox homeostasis and proteostasis in MM pathogenesis and drug resistance, which would be helpful in elucidating the still underdefined molecular pathways linking ER stress and oxidative stress in MM. Lastly, we highlight future research directions in the development of anti-myeloma therapy, focusing particularly on targeting redox signaling and ER stress responses.

Abstract 357: Hepatic ERK2 Suppresses Endoplasmic Reticulum Stress, Leading to Protection from Oxidative Stress and Endothelial Dysfunction

2013 ◽  
Vol 33 (suppl_1) ◽  
Author(s):  
Takehiko Kujiraoka ◽  
Yasushi Satoh ◽  
Makoto Ayaori ◽  
Yasunaga Shiraishi ◽  
Yuko Arai-Nakaya ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Insulin Resistance ◽  
Endoplasmic Reticulum ◽  
Fatty Acid ◽  
Endothelial Dysfunction ◽  
Er Stress ◽  
Vascular Complications ◽  
Metabolic Remodeling ◽  
And Oxidative Stress

Background Insulin signaling comprises 2 major cascades, the IRS/PI3K/Akt and Ras/Raf/MEK/ERK pathways. Many studies on the tissue-specific effects of the former pathway had been conducted, however, the role of the latter cascade in tissue-specific insulin resistance had not been investigated. High glucose/fatty acid toxicity, inflammation and oxidative stress, all of which are associated with insulin resistance, can activate ERK. Liver plays a central role of metabolism and hepatosteatosis (HST) is associated with vascular diseases. The aim of this study is to elucidate the role of hepatic ERK2 in HST, metabolic remodeling and endothelial dysfunction. Methods Serum biomarkers of vascular complications in human were compared between subjects with and without HST diagnosed by echography for regular medical checkup. Next, we created liver-specific ERK2 knockout mice (LE2KO) and fed them with a high-fat/high-sucrose diet (HFHSD) for 20 weeks. The histological analysis, the expression of hepatic sarco/endoplasmic reticulum (ER) Ca 2+ -ATPase 2 (SERCA2) and glucose-tolerance/insulin-sensitivity (GT/IS) were tested. Vascular superoxide production and endothelial function were evaluated with dihydroethidium staining and isometric tension measurement of aorta. Results The presence of HST significantly increased HOMA-IR, an indicator of insulin resistance or atherosclerotic index in human. HFHSD-fed LE2KO revealed a marked exacerbation in HST and metabolic remodeling represented by the impairment of GT/IS, elevated serum free fatty acid and hyperhomocysteinemia without changes in body weight, blood pressure and serum cholesterol/triglyceride levels. In the HFHSD-fed LE2KO, mRNA and protein expressions of hepatic SERCA2 were significantly decreased, which resulted in hepatic ER stress. Induction of vascular superoxide production and remarkable endothelial dysfunction were also observed in them. Conclusions Hepatic ERK2 revealed the suppression of hepatic ER stress and HST in vivo , which resulted in protection from vascular oxidative stress and endothelial dysfunction. HST with hepatic ER stress can be a prominent risk of vascular complications by metabolic remodeling and oxidative stress in obese-related diseases.

scholarly journals Protective Effect of Enalapril against Methionine-Enriched Diet-Induced Hypertension: Role of Endoplasmic Reticulum and Oxidative Stress

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Yanfen Zhou ◽  
Lianyou Zhao ◽  
Zhimin Zhang ◽  
Xuanhao Lu
Keyword(s):  
Oxidative Stress ◽  
Endoplasmic Reticulum ◽  
Protective Effect ◽  
Er Stress ◽  
Pathological Condition ◽  
Initiation Factor ◽  
Activating Transcription Factor 3 ◽  
Tbars Level ◽  
Induced Hypertension ◽  
And Oxidative Stress

In the present study, we investigated the effect of methionine-enriched diet (MED) on blood pressure in rats and examined the protective effect of enalapril, a widely used angiotensin converting enzyme inhibitors (ACEi) class antihypertensive drug. The results showed that MED induced significant increase of SBP and Ang II-induced contractile response in aortae of rats. MED significantly increased plasma levels of homocysteine (Hcy) and ACE. In addition, MED increased the phosphorylation of protein kinase R-like endoplasmic reticulum kinase (PERK) and eukaryotic initiation factor 2 (eIF2α) and expression of activating transcription factor 3 (ATF3) and ATF6 in aortae of rats, indicating the occurrence of endoplasmic reticulum (ER) stress. Moreover, MED resulted in oxidative stress as evidenced by significant increase of TBARS level and decrease of superoxide dismutase and catalase activities. Administration of enalapril could effectively inhibit these pathological changes induced by MED in rats. These results demonstrated that ACE-mediated ER stress and oxidative stress played an important role in high Hcy-induced hypertension and MED may exert a positive loop between the activation of ACE and accumulation of Hcy, aggravating the pathological condition of hypertension. The data provide novel insights into the mechanism of high Hcy-associated hypertension and the therapeutic efficiency of enalapril.

scholarly journals Apelin-13/APJ system attenuates early brain injury via suppression of endoplasmic reticulum stress-associated TXNIP/NLRP3 inflammasome activation and oxidative stress in a AMPK-dependent manner after subarachnoid hemorrhage in rats

2019 ◽  
Vol 16 (1) ◽  
Author(s):  
Weilin Xu ◽  
Tao Li ◽  
Liansheng Gao ◽  
Jingwei Zheng ◽  
Jun Yan ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Endoplasmic Reticulum ◽  
Subarachnoid Hemorrhage ◽  
Brain Injury ◽  
Er Stress ◽  
Early Brain Injury ◽  
Inflammasome Activation ◽  
Dependent Manner ◽  
Neuroprotective Effects ◽  
And Oxidative Stress

Abstract Background Neuroinflammation and oxidative stress play important roles in early brain injury following subarachnoid hemorrhage (SAH). This study is the first to show that activation of apelin receptor (APJ) by apelin-13 could reduce endoplasmic reticulum (ER)-stress-associated inflammation and oxidative stress after SAH. Methods Apelin-13, apelin siRNA, APJ siRNA, and adenosine monophosphate-activated protein kinase (AMPK) inhibitor-dorsomorphin were used to investigate if the activation of APJ could provide neuroprotective effects after SAH. Brain water content, neurological functions, blood-brain barrier (BBB) integrity, and inflammatory molecules were evaluated at 24 h after SAH. Western blotting and immunofluorescence staining were applied to assess the expression of target proteins. Results The results showed that endogenous apelin, APJ, and p-AMPK levels were significantly increased and peaked in the brain 24 h after SAH. In addition, administration of exogenous apelin-13 significantly alleviated neurological functions, attenuated brain edema, preserved BBB integrity, and also improved long-term spatial learning and memory abilities after SAH. The underlying mechanism of the neuroprotective effects of apelin-13 is that it suppresses microglia activation, prevents ER stress from overactivation, and reduces the levels of thioredoxin-interacting protein (TXNIP), NOD-like receptor pyrin domain-containing 3 protein (NLRP3), Bip, cleaved caspase-1, IL-1β, TNFα, myeloperoxidase (MPO), and reactive oxygen species (ROS). Furthermore, the use of APJ siRNA and dorsomorphin abolished the neuroprotective effects of apelin-13 on neuroinflammation and oxidative stress. Conclusions Exogenous apelin-13 binding to APJ attenuates early brain injury by reducing ER stress-mediated oxidative stress and neuroinflammation, which is at least partly mediated by the AMPK/TXNIP/NLRP3 signaling pathway.

Rhabdomyolysis induced AKI via the regulation of endoplasmic reticulum stress and oxidative stress in PTECs

RSC Advances ◽  
2016 ◽  
Vol 6 (111) ◽  
pp. 109639-109648 ◽  
Author(s):  
Yuying Feng ◽  
Liang Ma ◽  
Linfeng Liu ◽  
Hyokyoung Grace Hong ◽  
Xuemei Zhang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Endoplasmic Reticulum ◽  
Endoplasmic Reticulum Stress ◽  
Er Stress ◽  
And Oxidative Stress ◽  
Stress Activation

Mechanism for the role of ER stress and oxidative stress activation in rhabdomyolysis-associated AKI.

scholarly journals NADPH oxidase links endoplasmic reticulum stress, oxidative stress, and PKR activation to induce apoptosis

2010 ◽  
Vol 191 (6) ◽  
pp. 1113-1125 ◽  
Author(s):  
Gang Li ◽  
Christopher Scull ◽  
Lale Ozcan ◽  
Ira Tabas
Keyword(s):  
Oxidative Stress ◽  
Endoplasmic Reticulum ◽  
Er Stress ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Cellular Mechanisms ◽  
Apoptosis Pathway ◽  
Stress Oxidative ◽  
Induced Apoptosis ◽  
And Oxidative Stress

Endoplasmic reticulum (ER)–induced apoptosis and oxidative stress contribute to several chronic disease processes, yet molecular and cellular mechanisms linking ER stress and oxidative stress in the setting of apoptosis are poorly understood and infrequently explored in vivo. In this paper, we focus on a previously elucidated ER stress–apoptosis pathway whose molecular components have been identified and documented to cause apoptosis in vivo. We now show that nicotinamide adenine dinucleotide phosphate reduced oxidase (NOX) and NOX-mediated oxidative stress are induced by this pathway and that apoptosis is blocked by both genetic deletion of the NOX subunit NOX2 and by the antioxidant N-acetylcysteine. Unexpectedly, NOX and oxidative stress further amplify CCAAT/enhancer binding protein homologous protein (CHOP) induction through activation of the double-stranded RNA–dependent protein kinase (PKR). In vivo, NOX2 deficiency protects ER-stressed mice from renal cell CHOP induction and apoptosis and prevents renal dysfunction. These data provide new insight into how ER stress, oxidative stress, and PKR activation can be integrated to induce apoptosis in a pathophysiologically relevant manner.

scholarly journals The effect of selenium and polysaccharide of Atractylodes macrocephala Koidz. (PAMK) on endoplasmic reticulum stress and apoptosis in chicken spleen induced by heat stress

RSC Advances ◽  
2017 ◽  
Vol 7 (13) ◽  
pp. 7519-7525 ◽  
Author(s):  
Danning Xu ◽  
Wanyan Li ◽  
Bingxin Li ◽  
Yunbo Tian ◽  
Yunmao Huang
Keyword(s):  
Oxidative Stress ◽  
Endoplasmic Reticulum ◽  
Heat Stress ◽  
Endoplasmic Reticulum Stress ◽  
Er Stress ◽  
Chicken Spleen ◽  
Different Types ◽  
Atractylodes Macrocephala Koidz ◽  
Atractylodes Macrocephala ◽  
And Oxidative Stress

Endoplasmic reticulum (ER) stress and oxidative stress are involved in different types of stress induced injuries.

scholarly journals Roles and Therapeutic Implications of Endoplasmic Reticulum Stress and Oxidative Stress in Cardiovascular Diseases

Antioxidants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1167
Author(s):  
Yan Zhou ◽  
Dharmani Devi Murugan ◽  
Haroon Khan ◽  
Yu Huang ◽  
Wai San Cheang
Keyword(s):  
Oxidative Stress ◽  
Endoplasmic Reticulum ◽  
Cardiovascular Diseases ◽  
Er Stress ◽  
Metabolic Diseases ◽  
Critical Role ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Therapeutic Implications ◽  
And Oxidative Stress

In different pathological states that cause endoplasmic reticulum (ER) calcium depletion, altered glycosylation, nutrient deprivation, oxidative stress, DNA damage or energy perturbation/fluctuations, the protein folding process is disrupted and the ER becomes stressed. Studies in the past decade have demonstrated that ER stress is closely associated with pathogenesis of obesity, insulin resistance and type 2 diabetes. Excess nutrients and inflammatory cytokines associated with metabolic diseases can trigger or worsen ER stress. ER stress plays a critical role in the induction of endothelial dysfunction and atherosclerosis. Signaling pathways including AMP-activated protein kinase and peroxisome proliferator-activated receptor have been identified to regulate ER stress, whilst ER stress contributes to the imbalanced production between nitric oxide (NO) and reactive oxygen species (ROS) causing oxidative stress. Several drugs or herbs have been proved to protect against cardiovascular diseases (CVD) through inhibition of ER stress and oxidative stress. The present article reviews the involvement of ER stress and oxidative stress in cardiovascular dysfunction and the potential therapeutic implications.

Research on the effects of L-carnitine and trans-chalcone on endoplasmic reticulum stress and oxidative stress in high-fructose corn syrup-fed rats

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Velid Unsal ◽  
Köksal Deveci ◽  
Zeliha Cansel Ozmen ◽  
Mehmet Kemal Tumer
Keyword(s):  
Oxidative Stress ◽  
Endoplasmic Reticulum ◽  
Er Stress ◽  
Binding Protein ◽  
High Fructose Corn Syrup ◽  
Content Type ◽  
Group Iii ◽  
Group I ◽  
High Fructose ◽  
And Oxidative Stress

Purpose The debate on the metabolic effects of high fructose corn syrup (HFCS) continues. The deterioration of endoplasmic reticulum (ER) homeostasis is called ER stress. Glucose-regulated protein-78 (GRP-78) and X-box binding protein-1 (XBP-1) are key markers of ER stress and the therapeutic targets of diseases. Sterol regulatory element binding protein-1c (SREBP-1c) is the most important transcription factor that regulates the expression of enzymes for fatty acid synthesis. The purpose of this paper is to research the effects of L-carnitine and trans-chalcone on ER stress and oxidative stress parameters, and to explore the therapeutic potential of L-carnitine and trans-chalcone molecules. Design/methodology/approach Forty male wistar albino rats randomly selected were divided into five groups. All groups are fed with standard chow (ad libitum). While Group I was fed with drinking water, Group II, III, IV and V were fed with water containing 15% HFCS. L-carnitine was given to Group IV and trans-chalcone to Group V, and both were dissolved with DMSO and given intraperitoneally. Group III was not given anything additional. Findings While the amount of water consumption of HFCS-fed rats has increased, the amount of feed consumption has decreased. The weights of rats in Group II and Group III have increased significantly compared to Group I (p = 0.001, p = 0.001 respectively). In Group III, GRP78, XBP-1; malondialdehyde level (p < 0.001, p = 0.001, p = 0.041); total cholesterol, triglyceride, LDL levels (p = 0.001, p < 0.001, p = 0.009, p = 0.001, respectively) have increased significantly. Originality/value To the best of the authors’ knowledge, this study is the first report to show that excessive HFCS consumption causes oxidative stress and ER stress. The antioxidant and antiobesity properties of trans chalcone have been demonstrated. Extensive experimental and clinical studies should be conducted.

Sign in / Sign up

Export Citation Format

Share Document