scholarly journals Oxidative Stress, hogg1 Expression and NF‐κB Activity in Cells Exposed to Low Level Chromium

2003 ◽  
Vol 45 (5) ◽  
pp. 271-277 ◽  
Author(s):  
Yong‐Dae Kim ◽  
Sung‐Chul An ◽  
Tsunehiro Oyama ◽  
Toshihiro Kawamoto ◽  
Heon Kim
Keyword(s):  
2020 ◽  
Vol 17 (3) ◽  
pp. 259-266 ◽  
Author(s):  
Xuan Chen ◽  
Sumei Zhang ◽  
Peipei Shi ◽  
Yangli Su ◽  
Dong Zhang ◽  
...  

Objective: Ischemia-reperfusion (I/R) injury is a pathological feature of ischemic stroke. This study investigated the regulatory role of miR-485-5p in I/R injury. Methods: SH-SY5Y cells were induced with oxygen and glucose deprivation/reoxygenation (OGD/R) to mimic I/R injury in vitro. Cells were transfected with designated constructs (miR-485- 5p mimics, miR-485-5p inhibitor, lentiviral vectors overexpressing Rac1 or their corresponding controls). Cell viability was evaluated using the MTT assay. The concentrations of lactate dehydrogenase, malondialdehyde, and reactive oxygen species were detected to indicate the degree of oxidative stress. Flow cytometry and caspase-3 activity assay were used for apoptosis assessment. Dual-luciferase reporter assay was performed to confirm that Rac family small GTPase 1 (Rac1) was a downstream gene of miR-485-5p. Results: OGD/R resulted in decreased cell viability, elevated oxidative stress, increased apoptosis, and downregulated miR-485-5p expression in SH-SY5Y cells. MiR-485-5p upregulation alleviated I/R injury, evidenced by improved cell viability, decreased oxidative markers, and reduced apoptotic rate. OGD/R increased the levels of Rac1 and neurogenic locus notch homolog protein 2 (Notch2) signaling-related proteins in cells with normal miR-485-5p expression, whereas miR- 485-5p overexpression successfully suppressed OGD/R-induced upregulation of these proteins. Furthermore, the delivery of vectors overexpressing Rac1 in miR-485-5p mimics-transfected cells reversed the protective effect of miR-485-5p in cells with OGD/R-induced injury. Conclusion: This study showed that miR-485-5p protected cells following I/R injury via targeting Rac1/Notch2 signaling suggest that targeted upregulation of miR-485-5p might be a promising therapeutic option for the protection against I/R injury.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jee-Yun Park ◽  
Hee-Young Sohn ◽  
Young Ho Koh ◽  
Chulman Jo

AbstractCurcumin, a phytochemical extracted from Curcuma longa rhizomes, is known to be protective in neurons via activation of Nrf2, a master regulator of endogenous defense against oxidative stress in cells. However, the exact mechanism by which curcumin activates Nrf2 remains controversial. Here, we observed that curcumin induced the expression of genes downstream of Nrf2 such as HO-1, NQO1, and GST-mu1 in neuronal cells, and increased the level of Nrf2 protein. Notably, the level of p62 phosphorylation at S351 (S349 in human) was significantly increased in cells treated with curcumin. Additionally, curcumin-induced Nrf2 activation was abrogated in p62 knockout (−/−) MEFs, indicating that p62 phosphorylation at S351 played a crucial role in curcumin-induced Nrf2 activation. Among the kinases involved in p62 phosphorylation at S351, PKCδ was activated in curcumin-treated cells. The phosphorylation of p62 at S351 was enhanced by transfection of PKCδ expression plasmid; in contrast, it was inhibited in cells treated with PKCδ-specific siRNA. Together, these results suggest that PKCδ is mainly involved in curcumin-induced p62 phosphorylation and Nrf2 activation. Accordingly, we demonstrate for the first time that curcumin activates Nrf2 through PKCδ-mediated p62 phosphorylation at S351.


Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3427
Author(s):  
Ievgeniia Kocherova ◽  
Artur Bryja ◽  
Katarzyna Błochowiak ◽  
Mariusz Kaczmarek ◽  
Katarzyna Stefańska ◽  
...  

Photobiomodulation (PBM), also called low-level laser treatment (LLLT), has been considered a promising tool in periodontal treatment due to its anti-inflammatory and wound healing properties. However, photobiomodulation’s effectiveness depends on a combination of parameters, such as energy density, the duration and frequency of the irradiation sessions, and wavelength, which has been shown to play a key role in laser-tissue interaction. The objective of the study was to compare the in vitro effects of two different wavelengths—635 nm and 808 nm—on the human primary gingival fibroblasts in terms of viability, oxidative stress, inflammation markers, and specific gene expression during the four treatment sessions at power and energy density widely used in dental practice (100 mW, 4 J/cm2). PBM with both 635 and 808 nm at 4 J/cm2 increased the cell number, modulated extracellular oxidative stress and inflammation markers and decreased the susceptibility of human primary gingival fibroblasts to apoptosis through the downregulation of apoptotic-related genes (P53, CASP9, BAX). Moreover, modulation of mesenchymal markers expression (CD90, CD105) can reflect the possible changes in the differentiation status of irradiated fibroblasts. The most pronounced results were observed following the third irradiation session. They should be considered for the possible optimization of existing low-level laser irradiation protocols used in periodontal therapies.


2012 ◽  
Author(s):  
Ying-Ying Huang ◽  
Clark E. Tedford ◽  
Thomas McCarthy ◽  
Michael R. Hamblin

Author(s):  
Dumitriţa RUGINǍ ◽  
Adela PINTEA ◽  
Raluca PÂRLOG ◽  
Andreea VARGA

Oxidative stress causes biological changes responsible for carcinogenesis and aging in human cells. The retinal pigmented epithelium is continuously exposed to oxidative stress. Therefore reactive oxygen species (ROS) and products of lipid peroxidation accumulate in RPE. Neutralization of ROS occurs in retina by the action of antioxidant defence systems. In the present study, the protective effect of caffeic acid (3,4-dihydroxy cinnamic acid), a dietary phenolic compound, has been examined in normal and in oxidative stress conditions (500 µM peroxide oxygen) in cultures human epithelial pigment retinal cells (Nowak, M. et al.). The cell viability, the antioxidant enzymes activity (CAT, GPx, SOD) and the level of intracellular reactive oxygen species (ROS) were determined. Exposure to l00 µM caffeic acid for 24 h induced cellular changes indicating the protective effect of caffeic acid in RPE cells. Caffeic acid did not show any cytotoxic effect at concentrations lower than 200 μM in culture medium. Treatment of RPE cells with caffeic acid causes an increase of catalase, glutathione peroxidase and superoxide dismutase activity, especially in cells treated with hydrogen peroxide. Caffeic acid causes a decrease of ROS level in cells treated with hydrogen peroxide. This study proved that caffeic acid or food that contain high levels of this phenolic acid may have beneficial effects in prevention of retinal diseases associated with oxidative stress by improving antioxidant defence systems.


1995 ◽  
Vol 206 (1) ◽  
pp. 421-428 ◽  
Author(s):  
D. Gelvan ◽  
V. Moreno ◽  
D.A. Clopton ◽  
Q. Chen ◽  
P. Saltman

2010 ◽  
Vol 88 (3) ◽  
pp. 241-248 ◽  
Author(s):  
Garry X. Shen

Cardiovascular diseases are the predominant cause of death in patients with diabetes mellitus. Underlying mechanism for the susceptibility of diabetic patients to cardiovascular diseases remains unclear. Elevated oxidative stress was detected in diabetic patients and in animal models of diabetes. Hyperglycemia, oxidatively modified atherogenic lipoproteins, and advanced glycation end products are linked to oxidative stress in diabetes. Mitochondria are one of major sources of reactive oxygen species (ROS) in cells. Mitochondrial dysfunction increases electron leak and the generation of ROS from the mitochondrial respiratory chain (MRC). High levels of glucose and lipids impair the activities of MRC complex enzymes. NADPH oxidase (NOX) generates superoxide from NADPH in cells. Increased NOX activity was detected in diabetic patients. Hyperglycemia and hyperlipidemia increased the expression of NOX in vascular endothelial cells. Accumulated lines of evidence indicate that oxidative stress induced by excessive ROS production is linked to many processes associated with diabetic cardiovascular complications. Overproduction of ROS resulting from mitochondrial dysfunction or NOX activation is associated with uncoupling of endothelial nitric oxide synthase, which leads to reduced production of nitric oxide and endothelial-dependent vasodilation. Gene silence or inhibitor of NOX reduced oxidized or glycated LDL-induced expression of plasminogen activator inhibitor-1 in endothelial cells. Statins, hypoglycemic agents, and exercise may reduce oxidative stress in diabetic patients through the reduction of NOX activity or the improvement of mitochondrial function, which may prevent or postpone the development of cardiovascular complications.


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