Nicotinamide Nucleotide Transhydrogenase as a Novel Treatment Target in Adrenocortical Carcinoma

Abstract Adrenocortical carcinoma (ACC) is an aggressive malignancy with poor response to chemotherapy. In this study, we evaluated a potential new treatment target for ACC, focusing on the mitochondrial reduced form of NAD phosphate (NADPH) generator nicotinamide nucleotide transhydrogenase (NNT). NNT has a central role within mitochondrial antioxidant pathways, protecting cells from oxidative stress. Inactivating human NNT mutations result in congenital adrenal insufficiency. We hypothesized that NNT silencing in ACC cells will induce toxic levels of oxidative stress. To explore this, we transiently knocked down NNT in NCI-H295R ACC cells. As predicted, this manipulation increased intracellular levels of oxidative stress; this resulted in a pronounced suppression of cell proliferation and higher apoptotic rates, as well as sensitization of cells to chemically induced oxidative stress. Steroidogenesis was paradoxically stimulated by NNT loss, as demonstrated by mass spectrometry–based steroid profiling. Next, we generated a stable NNT knockdown model in the same cell line to investigate the longer lasting effects of NNT silencing. After long-term culture, cells adapted metabolically to chronic NNT knockdown, restoring their redox balance and resilience to oxidative stress, although their proliferation remained suppressed. This was associated with higher rates of oxygen consumption. The molecular pathways underpinning these responses were explored in detail by RNA sequencing and nontargeted metabolome analysis, revealing major alterations in nucleotide synthesis, protein folding, and polyamine metabolism. This study provides preclinical evidence of the therapeutic merit of antioxidant targeting in ACC as well as illuminating the long-term adaptive response of cells to oxidative stress.

Download Full-text

Hypermetabolism of glutathione, glutamate and ornithine via redox imbalance in methylglyoxal-induced peritoneal injury rats

The Journal of Biochemistry ◽

10.1093/jb/mvz077 ◽

2019 ◽

Author(s):

Ichiro Hirahara ◽

Eiji Kusano ◽

Denan Jin ◽

Shinji Takai

Keyword(s):

Oxidative Stress ◽

Intraperitoneal Administration ◽

Methionine Sulfoxide ◽

Mesenchymal Cell ◽

Oxidative Stress Marker ◽

Peritoneal Fibrosis ◽

Metabolome Analysis ◽

Glycation End Products ◽

Excessive Proliferation

Abstract Peritoneal dialysis (PD) is a blood purification treatment for patients with reduced renal function. However, the peritoneum is exposed to oxidative stress during PD and long-term PD results in peritoneal damage, leading to the termination of PD. Methylglyoxal (MGO) contained in commercial PD fluids is a source of strong oxidative stress. The aim of this study was to clarify the mechanism of MGO-induced peritoneal injury using metabolome analysis in rats. We prepared peritoneal fibrosis rats by intraperitoneal administration of PD fluids containing MGO for 21 days. As a result, MGO-induced excessive proliferation of mesenchymal cells with an accumulation of advanced glycation end-products (AGEs) at the surface of the thickened peritoneum in rats. The effluent levels of methionine sulfoxide, an oxidative stress marker and glutathione peroxidase activity were increased in the MGO-treated rats. The levels of glutathione, glutamate, aspartate, ornithine and AGEs were also increased in these rats. MGO upregulated the gene expression of transporters and enzymes related to the metabolism of glutathione, glutamate and ornithine in the peritoneum. These results suggest that MGO may induce peritoneal injury with mesenchymal cell proliferation via increased redox metabolism, directly or through the formation of AGEs during PD.

Download Full-text

Nicotinamide Nucleotide Transhydrogenase as a novel treatment target in adrenocortical carcinoma

Endocrine Abstracts ◽

10.1530/endoabs.56.gp23 ◽

2018 ◽

Author(s):

Vasileios Chortis ◽

Angela Taylor ◽

Craig Doig ◽

Mark Walsh ◽

Eirini Meimaridou ◽

...

Keyword(s):

Adrenocortical Carcinoma ◽

Treatment Target ◽

Nicotinamide Nucleotide Transhydrogenase ◽

Novel Treatment

Download Full-text

Effect of Methionine Restriction on Aging: Its Relationship to Oxidative Stress

Biomedicines ◽

10.3390/biomedicines9020130 ◽

2021 ◽

Vol 9 (2) ◽

pp. 130

Author(s):

Munehiro Kitada ◽

Yoshio Ogura ◽

Itaru Monno ◽

Jing Xu ◽

Daisuke Koya

Keyword(s):

Oxidative Stress ◽

Metabolic Health ◽

Polyamine Metabolism ◽

Lifespan Extension ◽

Methionine Metabolism ◽

Glutathione Synthesis ◽

Methyl Donors ◽

Methionine Restriction ◽

Adenosyl Methionine ◽

Species Production

Enhanced oxidative stress is closely related to aging and impaired metabolic health and is influenced by diet-derived nutrients and energy. Recent studies have shown that methionine restriction (MetR) is related to longevity and metabolic health in organisms from yeast to rodents. The effect of MetR on lifespan extension and metabolic health is mediated partially through a reduction in oxidative stress. Methionine metabolism is involved in the supply of methyl donors such as S-adenosyl-methionine (SAM), glutathione synthesis and polyamine metabolism. SAM, a methionine metabolite, activates mechanistic target of rapamycin complex 1 and suppresses autophagy; therefore, MetR can induce autophagy. In the process of glutathione synthesis in methionine metabolism, hydrogen sulfide (H2S) is produced through cystathionine-β-synthase and cystathionine-γ-lyase; however, MetR can induce increased H2S production through this pathway. Similarly, MetR can increase the production of polyamines such as spermidine, which are involved in autophagy. In addition, MetR decreases oxidative stress by inhibiting reactive oxygen species production in mitochondria. Thus, MetR can attenuate oxidative stress through multiple mechanisms, consequently associating with lifespan extension and metabolic health. In this review, we summarize the current understanding of the effects of MetR on lifespan extension and metabolic health, focusing on the reduction in oxidative stress.

Download Full-text

Blood–brain barrier disruption and ventricular enlargement are the earliest neuropathological changes in rats with repeated sub-concussive impacts over 2 weeks

Scientific Reports ◽

10.1038/s41598-021-88854-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Bailey Hiles-Murison ◽

Andrew P. Lavender ◽

Mark J. Hackett ◽

Joshua J. Armstrong ◽

Michael Nesbit ◽

...

Keyword(s):

Oxidative Stress ◽

Blood Brain Barrier ◽

Hippocampal Formation ◽

Brain Barrier ◽

Lateral Ventricles ◽

Blood Brain Barrier Disruption ◽

Blood Brain ◽

Brain Barrier Disruption ◽

Underlying Mechanisms

AbstractRepeated sub-concussive impact (e.g. soccer ball heading), a significantly lighter form of mild traumatic brain injury, is increasingly suggested to cumulatively alter brain structure and compromise neurobehavioural function in the long-term. However, the underlying mechanisms whereby repeated long-term sub-concussion induces cerebral structural and neurobehavioural changes are currently unknown. Here, we utilised an established rat model to investigate the effects of repeated sub-concussion on size of lateral ventricles, cerebrovascular blood–brain barrier (BBB) integrity, neuroinflammation, oxidative stress, and biochemical distribution. Following repeated sub-concussion 3 days per week for 2 weeks, the rats showed significantly enlarged lateral ventricles compared with the rats receiving sham-only procedure. The sub-concussive rats also presented significant BBB dysfunction in the cerebral cortex and hippocampal formation, whilst neuromotor function assessed by beamwalk and rotarod tests were comparable to the sham rats. Immunofluorescent and spectroscopic microscopy analyses revealed no significant changes in neuroinflammation, oxidative stress, lipid distribution or protein aggregation, within the hippocampus and cortex. These data collectively indicate that repeated sub-concussion for 2 weeks induce significant ventriculomegaly and BBB disruption, preceding neuromotor deficits.

Download Full-text

Crosstalk between Long-Term Sublethal Oxidative Stress and Detrimental Inflammation as Potential Drivers for Age-Related Retinal Degeneration

Antioxidants ◽

10.3390/antiox10010025 ◽

2020 ◽

Vol 10 (1) ◽

pp. 25

Author(s):

Lara Macchioni ◽

Davide Chiasserini ◽

Letizia Mezzasoma ◽

Magdalena Davidescu ◽

Pier Luigi Orvietani ◽

...

Keyword(s):

Oxidative Stress ◽

Molecular Mechanisms ◽

Age Related Macular Degeneration ◽

Inflammasome Activation ◽

Related Factor ◽

Nuclear Factor ◽

Rpe Cells ◽

Age Related ◽

Oxidative Insult

Age-related retinal degenerations, including age-related macular degeneration (AMD), are caused by the loss of retinal pigmented epithelial (RPE) cells and photoreceptors. The pathogenesis of AMD, deeply linked to the aging process, also involves oxidative stress and inflammatory responses. However, the molecular mechanisms contributing to the shift from healthy aging to AMD are still poorly understood. Since RPE cells in the retina are chronically exposed to a pro-oxidant microenvironment throughout life, we simulated in vivo conditions by growing ARPE-19 cells in the presence of 10 μM H2O2 for several passages. This long-term oxidative insult induced senescence in ARPE-19 cells without affecting cell proliferation. Global proteomic analysis revealed a dysregulated expression in proteins involved in antioxidant response, mitochondrial homeostasis, and extracellular matrix organization. The analyses of mitochondrial functionality showed increased mitochondrial biogenesis and ATP generation and improved response to oxidative stress. The latter, however, was linked to nuclear factor-κB (NF-κB) rather than nuclear factor erythroid 2–related factor 2 (Nrf2) activation. NF-κB hyperactivation also resulted in increased pro-inflammatory cytokines expression and inflammasome activation. Moreover, in response to additional pro-inflammatory insults, senescent ARPE-19 cells underwent an exaggerated inflammatory reaction. Our results indicate senescence as an important link between chronic oxidative insult and detrimental chronic inflammation, with possible future repercussions for therapeutic interventions.

Download Full-text

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.

Download Full-text

The Parkinson’s Disease-Associated Protein DJ-1 Protects Dictyostelium Cells from AMPK-Dependent Outcomes of Oxidative Stress

Cells ◽

10.3390/cells10081874 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1874

Author(s):

Suwei Chen ◽

Sarah J. Annesley ◽

Rasha A. F. Jasim ◽

Paul R. Fisher

Keyword(s):

Oxidative Stress ◽

Parkinson’S Disease ◽

Parkinson's Disease ◽

Mitochondrial Dysfunction ◽

Mitochondrial Respiration ◽

Cysteine Residue ◽

Reduced Form ◽

Dependent Manner ◽

Loss Of Function ◽

Cellular Pathology

Mitochondrial dysfunction has been implicated in the pathology of Parkinson’s disease (PD). In Dictyostelium discoideum, strains with mitochondrial dysfunction present consistent, AMPK-dependent phenotypes. This provides an opportunity to investigate if the loss of function of specific PD-associated genes produces cellular pathology by causing mitochondrial dysfunction with AMPK-mediated consequences. DJ-1 is a PD-associated, cytosolic protein with a conserved oxidizable cysteine residue that is important for the protein’s ability to protect cells from the pathological consequences of oxidative stress. Dictyostelium DJ-1 (encoded by the gene deeJ) is located in the cytosol from where it indirectly inhibits mitochondrial respiration and also exerts a positive, nonmitochondrial role in endocytosis (particularly phagocytosis). Its loss in unstressed cells impairs endocytosis and causes correspondingly slower growth, while also stimulating mitochondrial respiration. We report here that oxidative stress in Dictyostelium cells inhibits mitochondrial respiration and impairs phagocytosis in an AMPK-dependent manner. This adds to the separate impairment of phagocytosis caused by DJ-1 knockdown. Oxidative stress also combines with DJ-1 loss in an AMPK-dependent manner to impair or exacerbate defects in phototaxis, morphogenesis and growth. It thereby phenocopies mitochondrial dysfunction. These results support a model in which the oxidized but not the reduced form of DJ-1 inhibits AMPK in the cytosol, thereby protecting cells from the adverse consequences of oxidative stress, mitochondrial dysfunction and the resulting AMPK hyperactivity.

Download Full-text

Immunolocalization of antioxidant enzymes in testis of rams submitted to long-term heat stress

Zygote ◽

10.1017/s0967199419000467 ◽

2019 ◽

Vol 27 (6) ◽

pp. 432-435

Author(s):

Thais Rose dos Santos Hamilton ◽

Gabriela Esteves Duarte ◽

José Antonio Visintin ◽

Mayra Elena Ortiz D’Ávila Assumpção

Keyword(s):

Oxidative Stress ◽

Superoxide Dismutase ◽

Antioxidant Enzymes ◽

Heat Stress ◽

Glutathione Peroxidase ◽

Cell Types ◽

Treated Group ◽

Oxidative Balance ◽

Testicular Cells

SummaryLong-term heat stress (HS) induced by testicular insulation generates oxidative stress (OS) on the testicular environment; consequently activating antioxidant enzymes such as superoxide dismutase (SOD), glutathione reductase (GR) and glutathione peroxidase (GPx). The aim of this work was to immunolocalize antioxidant enzymes present in different cells within the seminiferous tubule when rams were submitted to HS. Rams were divided into control (n = 6) and treated group (n = 6), comprising rams subjected to testicular insulation for 240 h. After the testicular insulation period, rams were subjected to orchiectomy. Testicular fragments were submitted to immunohistochemistry for staining against SOD, GR and GPx enzymes. We observed immunolocalization of GPx in more cell types of the testis after HS and when compared with other enzymes. In conclusion, GPx is the main antioxidant enzyme identified in testicular cells in an attempt to maintain oxidative balance when HS occurs.

Download Full-text

Cellular stress signaling activates type-I IFN response through FOXO3-regulated lamin posttranslational modification

Nature Communications ◽

10.1038/s41467-020-20839-0 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Inah Hwang ◽

Hiroki Uchida ◽

Ziwei Dai ◽

Fei Li ◽

Teresa Sanchez ◽

...

Keyword(s):

Oxidative Stress ◽

Environmental Changes ◽

Type I ◽

Neurogenic Differentiation ◽

Forkhead Box ◽

Nuclear Lamin ◽

Neural Stem Progenitor Cells ◽

Subsequent Activation ◽

Methyl Group Transfer

AbstractNeural stem/progenitor cells (NSPCs) persist over the lifespan while encountering constant challenges from age or injury related brain environmental changes like elevated oxidative stress. But how oxidative stress regulates NSPC and its neurogenic differentiation is less clear. Here we report that acutely elevated cellular oxidative stress in NSPCs modulates neurogenic differentiation through induction of Forkhead box protein O3 (FOXO3)-mediated cGAS/STING and type I interferon (IFN-I) responses. We show that oxidative stress activates FOXO3 and its transcriptional target glycine-N-methyltransferase (GNMT) whose upregulation triggers depletion of s-adenosylmethionine (SAM), a key co-substrate involved in methyl group transfer reactions. Mechanistically, we demonstrate that reduced intracellular SAM availability disrupts carboxymethylation and maturation of nuclear lamin, which induce cytosolic release of chromatin fragments and subsequent activation of the cGAS/STING-IFN-I cascade to suppress neurogenic differentiation. Together, our findings suggest the FOXO3-GNMT/SAM-lamin-cGAS/STING-IFN-I signaling cascade as a critical stress response program that regulates long-term regenerative potential.

Download Full-text

Treatment of the Fluoroquinolone-Associated Disability: The Pathobiochemical Implications

Oxidative Medicine and Cellular Longevity ◽

10.1155/2017/8023935 ◽

2017 ◽

Vol 2017 ◽

pp. 1-15 ◽

Cited By ~ 2

Author(s):

Krzysztof Michalak ◽

Aleksandra Sobolewska-Włodarczyk ◽

Marcin Włodarczyk ◽

Justyna Sobolewska ◽

Piotr Woźniak ◽

...

Keyword(s):

Oxidative Stress ◽

Gene Expression ◽

Enzyme Activity ◽

Antibiotic Therapy ◽

Effective Treatment ◽

Social Problem ◽

Fenton Reaction ◽

Current Paper ◽

Bivalent Cations

Long-term fluoroquinolone-associated disability (FQAD) after fluoroquinolone (FQ) antibiotic therapy appears in recent years as a significant medical and social problem, because patients suffer for many years after prescribed antimicrobial FQ treatment from tiredness, concentration problems, neuropathies, tendinopathies, and other symptoms. The knowledge about the molecular activity of FQs in the cells remains unclear in many details. The effective treatment of this chronic state remains difficult and not effective. The current paper reviews the pathobiochemical properties of FQs, hints the directions for further research, and reviews the research concerning the proposed treatment of patients. Based on the analysis of literature, the main directions of possible effective treatment of FQAD are proposed: (a) reduction of the oxidative stress, (b) restoring reduced mitochondrion potential ΔΨm, (c) supplementation of uni- and bivalent cations that are chelated by FQs and probably ineffectively transported to the cell (caution must be paid to Fe and Cu because they may generate Fenton reaction), (d) stimulating the mitochondrial proliferation, (e) removing FQs permanently accumulated in the cells (if this phenomenon takes place), and (f) regulating the disturbed gene expression and enzyme activity.

Download Full-text