scholarly journals Oxidative Stress and Proteostasis Network: Culprit and Casualty of Alzheimer’s-Like Neurodegeneration

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Fabio Di Domenico ◽  
Elizabeth Head ◽  
D. Allan Butterfield ◽  
Marzia Perluigi

Free radical-mediated damage to proteins is particularly important in aging and age-related neurodegenerative diseases, because in the majority of cases it is a non-reversible phenomenon that requires clearance systems for removal. Major consequences of protein oxidation are loss of protein function and the formation of large protein aggregates, which are often toxic to cells if allowed to accumulate. Deposition of aggregated, misfolded, and oxidized proteins may also result from the impairment of protein quality control (PQC) system, including protein unfolded response, proteasome, and autophagy. Perturbations of such components of the proteostasis network that provides a critical protective role against stress conditions are emerging as relevant factor in triggering neuronal death. In this outlook paper, we discuss the role of protein oxidation as a major contributing factor for the impairment of the PQC regulating protein folding, surveillance, and degradation. Recent studies from our group and from others aim to better understand the link between Down syndrome and Alzheimer’s disease neuropathology. We propose oxidative stress and alteration of proteostasis network as a possible unifying mechanism triggering neurodegeneration.

2021 ◽  
Vol 22 (15) ◽  
pp. 7765
Author(s):  
Youichirou Higashi ◽  
Takaaki Aratake ◽  
Takahiro Shimizu ◽  
Shogo Shimizu ◽  
Motoaki Saito

Stroke is a major cause of death worldwide, leading to serious disability. Post-ischemic injury, especially in the cerebral ischemia-prone hippocampus, is a serious problem, as it contributes to vascular dementia. Many studies have shown that in the hippocampus, ischemia/reperfusion induces neuronal death through oxidative stress and neuronal zinc (Zn2+) dyshomeostasis. Glutathione (GSH) plays an important role in protecting neurons against oxidative stress as a major intracellular antioxidant. In addition, the thiol group of GSH can function as a principal Zn2+ chelator for the maintenance of Zn2+ homeostasis in neurons. These lines of evidence suggest that neuronal GSH levels could be a key factor in post-stroke neuronal survival. In neurons, excitatory amino acid carrier 1 (EAAC1) is involved in the influx of cysteine, and intracellular cysteine is the rate-limiting substrate for the synthesis of GSH. Recently, several studies have indicated that cysteine uptake through EAAC1 suppresses ischemia-induced neuronal death via the promotion of hippocampal GSH synthesis in ischemic animal models. In this article, we aimed to review and describe the role of GSH in hippocampal neuroprotection after ischemia/reperfusion, focusing on EAAC1.


2021 ◽  
Vol 22 (3) ◽  
pp. 1200
Author(s):  
Yoshimi Kishimoto ◽  
Kazuo Kondo ◽  
Yukihiko Momiyama

Atherosclerotic disease, such as coronary artery disease (CAD), is known to be a chronic inflammatory disease, as well as an age-related disease. Excessive oxidative stress produced by reactive oxygen species (ROS) contributes to the pathogenesis of atherosclerosis. Sestrin2 is an anti-oxidant protein that is induced by various stresses such as hypoxia, DNA damage, and oxidative stress. Sestrin2 is also suggested to be associated with aging. Sestrin2 is expressed and secreted mainly by macrophages, endothelial cells, and cardiomyocytes. Sestrin2 plays an important role in suppressing the production and accumulation of ROS, thus protecting cells from oxidative damage. Since sestrin2 is reported to have anti-oxidant and anti-inflammatory properties, it may play a protective role against the progression of atherosclerosis and may be a potential therapeutic target for the amelioration of atherosclerosis. Regarding the association between blood sestrin2 levels and atherosclerotic disease, the blood sestrin2 levels in patients with CAD or carotid atherosclerosis were reported to be high. High blood sestrin2 levels in patients with such atherosclerotic disease may reflect a compensatory response to increased oxidative stress and may help protect against the progression of atherosclerosis. This review describes the protective role of sestrin2 against the progression of atherosclerotic and cardiac diseases.


2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Janusz Blasiak ◽  
Russel J. Reiter ◽  
Kai Kaarniranta

Melatonin, an indoleamine, is synthesized mainly in the pineal gland in a circadian fashion, but it is produced in many other organs, including the retina, which seems to be especially important as the eye is a primary recipient of circadian signals. Melatonin displays strong antioxidative properties, which predispose it to play a protective role in many human pathologies associated with oxidative stress, including premature aging and degenerative disease. Therefore, melatonin may play a role in age-related macular degeneration (AMD), a disease affecting photoreceptors, and retinal pigment epithelium (RPE) with an established role of oxidative stress in its pathogenesis. Several studies have shown that melatonin could exert the protective effect against damage to RPE cells evoked by reactive oxygen species (ROS), but it has also been reported to increase ROS-induced damage to photoreceptors and RPE. Melatonin behaves like synthetic mitochondria-targeted antioxidants, which concentrate in mitochondria at relatively high levels; thus, melatonin may prevent mitochondrial damage in AMD. The retina contains telomerase, an enzyme implicated in maintaining the length of telomeres, and oxidative stress inhibits telomere synthesis, while melatonin overcomes this effect. These features support considering melatonin as a preventive and therapeutic agent in the treatment of AMD.


Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 160
Author(s):  
Vladana Domazetovic ◽  
Irene Falsetti ◽  
Caterina Viglianisi ◽  
Kristian Vasa ◽  
Cinzia Aurilia ◽  
...  

Vitamin E, a fat-soluble compound, possesses both antioxidant and non-antioxidant properties. In this study we evaluated, in intestinal HT29 cells, the role of natural tocopherols, α-Toc and δ-Toc, and two semi-synthetic derivatives, namely bis-δ-Toc sulfide (δ-Toc)2S and bis-δ-Toc disulfide (δ-Toc)2S2, on TNFα-induced oxidative stress, and intercellular adhesion molecule-1 (ICAM-1) and claudin-2 (Cl-2) expression. The role of tocopherols was compared to that of N-acetylcysteine (NAC), an antioxidant precursor of glutathione synthesis. The results show that all tocopherol containing derivatives used, prevented TNFα-induced oxidative stress and the increase of ICAM-1 and Cl-2 expression, and that (δ-Toc)2S and (δ-Toc)2S2 are more effective than δ-Toc and α-Toc. The beneficial effects demonstrated were due to tocopherol antioxidant properties, but suppression of TNFα-induced Cl-2 expression seems not only to be related with antioxidant ability. Indeed, while ICAM-1 expression is strongly related to the intracellular redox state, Cl-2 expression is TNFα-up-regulated by both redox and non-redox dependent mechanisms. Since ICAM-1 and Cl-2 increase intestinal bowel diseases, and cause excessive recruitment of immune cells and alteration of the intestinal barrier, natural and, above all, semi-synthetic tocopherols may have a potential role as a therapeutic support against intestinal chronic inflammation, in which TNFα represents an important proinflammatory mediator.


Author(s):  
Basiru Olaitan Ajiboye ◽  
Babatunji Emmanuel Oyinloye ◽  
Jennifer Chidera Awurum ◽  
Sunday Amos Onikanni ◽  
Adedotun Adefolalu ◽  
...  

Abstract Objectives The current study evaluates the protective role of aqueous extract of Sterculia tragacantha leaf (AESTL) on pancreatic gene expressions (insulin, PCNA, PDX-1, KI-67 and GLP-1R) and oxidative stress parameters in streptozotocin-induced diabetic rats. Methods Diabetes mellitus was induced into the experimental Wistar animals via intraperitoneal (IP) injection of streptozotocin (35 mg/kg body weight) and 5% glucose water was given to the rats for 24 h after induction. The animals were categorized into five groups of 10 rats each as follows normal control, diabetic control, diabetic rats administered AESTL (150 and 300 mg/kg body weight) and diabetic rats administered metformin (200 mg/kg) orally for two weeks. Thereafter, the animals were euthanized, blood sample collected, pancreas harvested and some pancreatic gene expressions (such as insulin, PCNA, PDX-1, KI-67, and GLP-1R)s as well as oxidative stress parameters were analyzed. Results The results revealed that AESTL significantly (p<0.05) reduced fasting blood glucose level, food and water intake, and lipid peroxidation in diabetic rats. Diabetic rats administered different doses of AESTL showed a substantial upsurge in body weight, antioxidant enzyme activities, and pancreatic gene expressions (insulin, PCNA, PDX-1, KI-67, and GLP-1R). Conclusions It can therefore be concluded that AESTL has the ability to protect the pancreas during diabetes mellitus conditions.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rawshan Choudhury ◽  
Nadhim Bayatti ◽  
Richard Scharff ◽  
Ewa Szula ◽  
Viranga Tilakaratna ◽  
...  

AbstractRetinal pigment epithelial (RPE) cells that underlie the neurosensory retina are essential for the maintenance of photoreceptor cells and hence vision. Interactions between the RPE and their basement membrane, i.e. the inner layer of Bruch’s membrane, are essential for RPE cell health and function, but the signals induced by Bruch’s membrane engagement, and their contributions to RPE cell fate determination remain poorly defined. Here, we studied the functional role of the soluble complement regulator and component of Bruch’s membrane, Factor H-like protein 1 (FHL-1). Human primary RPE cells adhered to FHL-1 in a manner that was eliminated by either mutagenesis of the integrin-binding RGD motif in FHL-1 or by using competing antibodies directed against the α5 and β1 integrin subunits. These short-term experiments reveal an immediate protein-integrin interaction that were obtained from primary RPE cells and replicated using the hTERT-RPE1 cell line. Separate, longer term experiments utilising RNAseq analysis of hTERT-RPE1 cells bound to FHL-1, showed an increased expression of the heat-shock protein genes HSPA6, CRYAB, HSPA1A and HSPA1B when compared to cells bound to fibronectin (FN) or laminin (LA). Pathway analysis implicated changes in EIF2 signalling, the unfolded protein response, and mineralocorticoid receptor signalling as putative pathways. Subsequent cell survival assays using H2O2 to induce oxidative stress-induced cell death suggest hTERT-RPE1 cells had significantly greater protection when bound to FHL-1 or LA compared to plastic or FN. These data show a non-canonical role of FHL-1 in protecting RPE cells against oxidative stress and identifies a novel interaction that has implications for ocular diseases such as age-related macular degeneration.


2021 ◽  
Vol 22 (3) ◽  
pp. 1296
Author(s):  
Yue Ruan ◽  
Subao Jiang ◽  
Adrian Gericke

Age-related macular degeneration (AMD) is a common irreversible ocular disease characterized by vision impairment among older people. Many risk factors are related to AMD and interact with each other in its pathogenesis. Notably, oxidative stress and choroidal vascular dysfunction were suggested to be critically involved in AMD pathogenesis. In this review, we give an overview on the factors contributing to the pathophysiology of this multifactorial disease and discuss the role of reactive oxygen species and vascular function in more detail. Moreover, we give an overview on therapeutic strategies for patients suffering from AMD.


2021 ◽  
pp. 117996
Author(s):  
Barbara Flasz ◽  
Marta Dziewięcka ◽  
Andrzej Kędziorski ◽  
Monika Tarnawska ◽  
Jan Augustyniak ◽  
...  

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