Oxidative Stress in the Healthy and Wounded Hepatocyte: A Cellular Organelles Perspective

Accurate control of the cell redox state is mandatory for maintaining the structural integrity and physiological functions. This control is achieved both by a fine-tuned balance between prooxidant and anti-oxidant molecules and by spatial and temporal confinement of the oxidative species. The diverse cellular compartments each, although structurally and functionally related, actively maintain their own redox balance, which is necessary to fulfill specialized tasks. Many fundamental cellular processes such as insulin signaling, cell proliferation and differentiation and cell migration and adhesion, rely on localized changes in the redox state of signal transducers, which is mainly mediated by hydrogen peroxide (H2O2). Therefore, oxidative stress can also occur long before direct structural damage to cellular components, by disruption of the redox circuits that regulate the cellular organelles homeostasis. The hepatocyte is a systemic hub integrating the whole body metabolic demand, iron homeostasis and detoxification processes, all of which are redox-regulated processes. Imbalance of the hepatocyte’s organelles redox homeostasis underlies virtually any liver disease and is a field of intense research activity. This review recapitulates the evolving concept of oxidative stress in the diverse cellular compartments, highlighting the principle mechanisms of oxidative stress occurring in the healthy and wounded hepatocyte.

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Oxidoreduction of protein thiols in redox regulation

Biochemical Society Transactions ◽

10.1042/bst0331378 ◽

2005 ◽

Vol 33 (6) ◽

pp. 1378-1381 ◽

Cited By ~ 45

Author(s):

P. Ghezzi

Keyword(s):

Oxidative Stress ◽

Redox State ◽

Redox Regulation ◽

Regulatory Mechanism ◽

Protein Damage ◽

The Past ◽

Protein Thiols ◽

Cellular Compartments

Protein cysteines can undergo various forms of oxidation, some of them reversible (disulphide formation, glutathionylation and S-nitrosylation). While in the past these were viewed as protein damage in the context of oxidative stress, there is growing interest in oxidoreduction of protein thiols/disulphides as a regulatory mechanism. This review discusses the evolution of the concept of redox regulation from that of oxidative stress and the redox state of protein cysteines in different cellular compartments.

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Imaging NAD(H) Redox Alterations in Cryopreserved Alveolar Macrophages from Ozone-Exposed Mice and the Impact of Nutrient Starvation during Long Lag Times

Antioxidants ◽

10.3390/antiox10050767 ◽

2021 ◽

Vol 10 (5) ◽

pp. 767

Author(s):

He N. Xu ◽

Joanna Floros ◽

Lin Z. Li ◽

Shaili Amatya

Keyword(s):

Oxidative Stress ◽

Alveolar Macrophages ◽

Redox State ◽

Redox Status ◽

Nutrient Starvation ◽

Ozone Exposure ◽

Reduced Form ◽

Time Period ◽

Lag Times ◽

The Impact

Employing the optical redox imaging technique, we previously identified a significant redox shift of nicotinamide adenine dinucleotide (NAD and the reduced form NADH) in freshly isolated alveolar macrophages (AM) from ozone-exposed mice. The goal here was twofold: (a) to determine the NAD(H) redox shift in cryopreserved AM isolated from ozone-exposed mice and (b) to investigate whether there is a difference in the redox status between cryopreserved and freshly isolated AM. We found: (i) AM from ozone-exposed mice were in a more oxidized redox state compared to that from filtered air (FA)-exposed mice, consistent with the results obtained from freshly isolated mouse AM; (ii) under FA exposure, there was no significant NAD(H) redox difference between fresh AM that had been placed on ice for 2.5 h and cryopreserved AM; however, under ozone exposure, fresh AM were more oxidized than cryopreserved AM; (iii) via the use of nutrient starvation and replenishment and H2O2-induced oxidative stress of an AM cell line, we showed that this redox difference between cryopreserved and freshly isolated AM is likely the result of the double “hit”, i.e., the ozone-induced oxidative stress plus nutrient starvation that prevented freshly isolated AM from a full recovery after being on ice for a prolonged time period. The cryopreservation technique we developed eliminates/minimizes the effects of oxidative stress and nutrient starvation on cells. This method can be adopted to preserve lung macrophages from animal models or clinical patients for further investigations.

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Systemic oxidative stress is associated with lower aerobic capacity and impaired skeletal muscle energy metabolism in heart failure patients

Scientific Reports ◽

10.1038/s41598-021-81736-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Takashi Yokota ◽

Shintaro Kinugawa ◽

Kagami Hirabayashi ◽

Mayumi Yamato ◽

Shingo Takada ◽

...

Keyword(s):

Oxidative Stress ◽

Heart Failure ◽

Skeletal Muscle ◽

Energy Metabolism ◽

Aerobic Capacity ◽

Plantar Flexion ◽

Exercise Intolerance ◽

Whole Body ◽

Resonance Spectroscopy ◽

Systemic Oxidative Stress

AbstractOxidative stress plays a role in the progression of chronic heart failure (CHF). We investigated whether systemic oxidative stress is linked to exercise intolerance and skeletal muscle abnormalities in patients with CHF. We recruited 30 males: 17 CHF patients, 13 healthy controls. All participants underwent blood testing, cardiopulmonary exercise testing, and magnetic resonance spectroscopy (MRS). The serum thiobarbituric acid reactive substances (TBARS; lipid peroxides) were significantly higher (5.1 ± 1.1 vs. 3.4 ± 0.7 μmol/L, p < 0.01) and the serum activities of superoxide dismutase (SOD), an antioxidant, were significantly lower (9.2 ± 7.1 vs. 29.4 ± 9.7 units/L, p < 0.01) in the CHF cohort versus the controls. The oxygen uptake (VO2) at both peak exercise and anaerobic threshold was significantly depressed in the CHF patients; the parameters of aerobic capacity were inversely correlated with serum TBARS and positively correlated with serum SOD activity. The phosphocreatine loss during plantar-flexion exercise and intramyocellular lipid content in the participants' leg muscle measured by 31phosphorus- and 1proton-MRS, respectively, were significantly elevated in the CHF patients, indicating abnormal intramuscular energy metabolism. Notably, the skeletal muscle abnormalities were related to the enhanced systemic oxidative stress. Our analyses revealed that systemic oxidative stress is related to lowered whole-body aerobic capacity and skeletal muscle dysfunction in CHF patients.

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Serum Albumin Redox States: More than Oxidative Stress Biomarker

Antioxidants ◽

10.3390/antiox10040503 ◽

2021 ◽

Vol 10 (4) ◽

pp. 503

Author(s):

Fuka Tabata ◽

Yasuaki Wada ◽

Satomi Kawakami ◽

Kazuhiro Miyaji

Keyword(s):

Oxidative Stress ◽

Serum Albumin ◽

Animal Studies ◽

Redox State ◽

Ex Vivo ◽

Pathological Condition ◽

Analytical Techniques ◽

Cysteine Residue ◽

Research Field ◽

Systemic Oxidative Stress

Serum albumin is the most abundant circulating protein in mammals including humans. It has three isoforms according to the redox state of the free cysteine residue at position 34, named as mercaptalbumin (reduced albumin), non-mercaptalbumin-1 and -2 (oxidized albumin), respectively. The serum albumin redox state has long been viewed as a biomarker of systemic oxidative stress, as the redox state shifts to a more oxidized state in response to the severity of the pathological condition in various diseases such as liver diseases and renal failures. However, recent ex vivo studies revealed oxidized albumin per se could aggravate the pathological conditions. Furthermore, the possibility of the serum albumin redox state as a sensitive protein nutrition biomarker has also been demonstrated in a series of animal studies. A paradigm shift is thus ongoing in the research field of the serum albumin. This article provides an updated overview of analytical techniques for serum albumin redox state and its association with human health, focusing on recent findings.

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Role of hepcidin in oxidative stress and cell death of cultured mouse renal collecting duct cells: protection against iron and sensitization to cadmium

Archives of Toxicology ◽

10.1007/s00204-021-03106-z ◽

2021 ◽

Author(s):

Stephanie Probst ◽

Johannes Fels ◽

Bettina Scharner ◽

Natascha A. Wolff ◽

Eleni Roussa ◽

...

Keyword(s):

Oxidative Stress ◽

Cell Death ◽

Cell Fate ◽

Catalase Activity ◽

Metal Ion ◽

Iron Homeostasis ◽

Collecting Duct ◽

Duct Cell ◽

Plasmid Transfection

AbstractThe liver hormone hepcidin regulates systemic iron homeostasis. Hepcidin is also expressed by the kidney, but exclusively in distal nephron segments. Several studies suggest hepcidin protects against kidney damage involving Fe2+ overload. The nephrotoxic non-essential metal ion Cd2+ can displace Fe2+ from cellular biomolecules, causing oxidative stress and cell death. The role of hepcidin in Fe2+ and Cd2+ toxicity was assessed in mouse renal cortical [mCCD(cl.1)] and inner medullary [mIMCD3] collecting duct cell lines. Cells were exposed to equipotent Cd2+ (0.5–5 μmol/l) and/or Fe2+ (50–100 μmol/l) for 4–24 h. Hepcidin (Hamp1) was transiently silenced by RNAi or overexpressed by plasmid transfection. Hepcidin or catalase expression were evaluated by RT-PCR, qPCR, immunoblotting or immunofluorescence microscopy, and cell fate by MTT, apoptosis and necrosis assays. Reactive oxygen species (ROS) were detected using CellROX™ Green and catalase activity by fluorometry. Hepcidin upregulation protected against Fe2+-induced mIMCD3 cell death by increasing catalase activity and reducing ROS, but exacerbated Cd2+-induced catalase dysfunction, increasing ROS and cell death. Opposite effects were observed with Hamp1 siRNA. Similar to Hamp1 silencing, increased intracellular Fe2+ prevented Cd2+ damage, ROS formation and catalase disruption whereas chelation of intracellular Fe2+ with desferrioxamine augmented Cd2+ damage, corresponding to hepcidin upregulation. Comparable effects were observed in mCCD(cl.1) cells, indicating equivalent functions of renal hepcidin in different collecting duct segments. In conclusion, hepcidin likely binds Fe2+, but not Cd2+. Because Fe2+ and Cd2+ compete for functional binding sites in proteins, hepcidin affects their free metal ion pools and differentially impacts downstream processes and cell fate.

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Contribution of Adipose Tissue Oxidative Stress to Obesity-Associated Diabetes Risk and Ethnic Differences: Focus on Women of African Ancestry

Antioxidants ◽

10.3390/antiox10040622 ◽

2021 ◽

Vol 10 (4) ◽

pp. 622

Author(s):

Pamela A. Nono Nankam ◽

Télesphore B. Nguelefack ◽

Julia H. Goedecke ◽

Matthias Blüher

Keyword(s):

Oxidative Stress ◽

Adipose Tissue ◽

Metabolic Diseases ◽

African Ancestry ◽

Fat Distribution ◽

African Women ◽

European Ancestry ◽

Whole Body ◽

Redox Equilibrium ◽

Systemic Oxidative Stress

Adipose tissue (AT) storage capacity is central in the maintenance of whole-body homeostasis, especially in obesity states. However, sustained nutrients overflow may dysregulate this function resulting in adipocytes hypertrophy, AT hypoxia, inflammation and oxidative stress. Systemic inflammation may also contribute to the disruption of AT redox equilibrium. AT and systemic oxidative stress have been involved in the development of obesity-associated insulin resistance (IR) and type 2 diabetes (T2D) through several mechanisms. Interestingly, fat accumulation, body fat distribution and the degree of how adiposity translates into cardio-metabolic diseases differ between ethnicities. Populations of African ancestry have a higher prevalence of obesity and higher T2D risk than populations of European ancestry, mainly driven by higher rates among African women. Considering the reported ethnic-specific differences in AT distribution and function and higher levels of systemic oxidative stress markers, oxidative stress is a potential contributor to the higher susceptibility for metabolic diseases in African women. This review summarizes existing evidence supporting this hypothesis while acknowledging a lack of data on AT oxidative stress in relation to IR in Africans, and the potential influence of other ethnicity-related modulators (e.g., genetic-environment interplay, socioeconomic factors) for consideration in future studies with different ethnicities.

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A manganese oxide nanozyme prevents the oxidative damage of biomolecules without affecting the endogenous antioxidant system

Nanoscale ◽

10.1039/c8nr09397k ◽

2019 ◽

Vol 11 (9) ◽

pp. 3855-3863 ◽

Cited By ~ 22

Author(s):

Namrata Singh ◽

Mohammed Azharuddin Savanur ◽

Shubhi Srivastava ◽

Patrick D'Silva ◽

Govindasamy Mugesh

Keyword(s):

Oxidative Stress ◽

Oxidative Damage ◽

Manganese Oxide ◽

Antioxidant System ◽

Mammalian Cells ◽

Redox State ◽

Stress Conditions ◽

System P ◽

Endogenous Antioxidant ◽

Antioxidant Machinery

Multi-enzyme mimetic Mn3O4 nanoflowers (Mp) modulate the redox state of mammalian cells without altering the cellular antioxidant machinery under oxidative stress conditions.

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Reactive Oxygen Species-Mediated Control of Mitochondrial Biogenesis

International Journal of Cell Biology ◽

10.1155/2012/403870 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 36

Author(s):

Edgar D. Yoboue ◽

Anne Devin

Keyword(s):

Oxidative Stress ◽

Mitochondrial Biogenesis ◽

Redox State ◽

Mitochondrial Genomes ◽

Oxygen Species ◽

Mitochondrial Content ◽

Cellular Redox ◽

High Importance ◽

Complex Process ◽

Long Time

Mitochondrial biogenesis is a complex process. It necessitates the contribution of both the nuclear and the mitochondrial genomes and therefore crosstalk between the nucleus and mitochondria. It is now well established that cellular mitochondrial content can vary according to a number of stimuli and physiological states in eukaryotes. The knowledge of the actors and signals regulating the mitochondrial biogenesis is thus of high importance. The cellular redox state has been considered for a long time as a key element in the regulation of various processes. In this paper, we report the involvement of the oxidative stress in the regulation of some actors of mitochondrial biogenesis.

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