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Molecules (Basel, Switzerland) Aug 2022Nicotinamide nucleotide transhydrogenase (NNT) is involved in decreasing melanogenesis through tyrosinase degradation induced by cellular redox changes. Nicotinamide is...
Nicotinamide nucleotide transhydrogenase (NNT) is involved in decreasing melanogenesis through tyrosinase degradation induced by cellular redox changes. Nicotinamide is a component of coenzymes, such as NAD, NADH, NADP, and NADPH, and its levels are modulated by NNT. Vitamin C and polydeoxyribonucleotide (PDRN) are also known to decrease skin pigmentation. We evaluated whether a mixture of nicotinamide, vitamin C, and PDRN (NVP-mix) decreased melanogenesis by modulating mitochondrial oxidative stress and NNT expression in UV-B-irradiated animals and in an in vitro model of melanocytes treated with conditioned media (CM) from UV-B-irradiated keratinocytes. The expression of NNT, GSH/GSSG, and NADPH/NADP in UV-B-irradiated animal skin was significantly decreased by UV-B radiation but increased by NVP-mix treatment. The expression of NNT, GSH/GSSG, and NADPH/NADP ratios decreased in melanocytes after CM treatment, although they increased after NVP-mix administration. In NNT-silenced melanocytes, the GSH/GSSG and NADPH/NADP ratios were further decreased by CM compared with normal melanocytes. NVP-mix decreased melanogenesis signals, such as MC1R, MITF, TYRP1, and TYRP2, and decreased melanosome transfer-related signals, such as RAB32 and RAB27A, in UV-B-irradiated animal skin. NVP-mix also decreased MC1R, MITF, TYRP1, TYRP2, RAB32, and RAB27A in melanocytes treated with CM from UV-irradiated keratinocytes. The expression of MC1R and MITF in melanocytes after CM treatment was unchanged by NNT silencing. However, the expression of TYRP1, TYRP2, RAB32, and RAB27A increased in NNT-silenced melanocytes after CM treatment. NVP-mix also decreased tyrosinase activity and melanin content in UV-B-irradiated animal skin and CM-treated melanocytes. In conclusion, NVP-mix decreased mitochondrial oxidative stress by increasing NNT expression and decreased melanogenesis by decreasing MC1R/MITF, tyrosinase, TYRP1, and TYRP2.
Topics: Animals; Ascorbic Acid; Glutathione Disulfide; Melanins; Melanocytes; Monophenol Monooxygenase; NADP; NADP Transhydrogenases; Niacinamide; Polydeoxyribonucleotides; Vitamins
PubMed: 35956878
DOI: 10.3390/molecules27154923 -
Journal of Experimental & Clinical... Sep 2022Oxidative stress is a highly active metabolic process in the liver, that poses great threats to disseminated tumor cells during their colonization. Here, we aimed to...
BACKGROUND
Oxidative stress is a highly active metabolic process in the liver, that poses great threats to disseminated tumor cells during their colonization. Here, we aimed to investigate how colorectal cancer (CRC) cells overcome lipid peroxidation to sustain their metastatic colonization in the liver.
METHODS
Orthotopic colorectal liver metastasis (CRLM) and CRC liver colonization mouse models were constructed to determine the roles of lipid peroxidation and AADAC in CRC liver colonization. The levels of lipid peroxidation were detected in cells or tissues. AADAC overexpression in LMs and its clinical relevance were analyzed. The oncogenic role of AADAC in CRC liver colonization was evaluated in cell experiments.
RESULTS
Compared with primary tumors (PTs), liver metastases (LMs) showed significantly lower glutathione to oxidized glutathione (GSH/GSSG) ratio and higher malondialdehyde (MDA) levels in CRLM patients and orthotopic mouse models. Inhibition of lipid peroxidation by liproxstatin-1 promoted CRC liver colonization in mouse models. RNA-seq results revealed AADAC as the most significantly upregulated lipid metabolism related gene in LMs compared with PTs. Analyses of datasets and patient and mouse model samples confirmed that AADAC was upregulated in LMs compared with PTs, and was correlated with poor prognosis. AADAC promoted cell proliferation, and facilitated liver colonization in a mouse model by reducing ROS accumulation, which led to lipid peroxidation and ferroptosis. Mechanistically, AADAC upregulated SLC7A11 by activating NRF2 to inhibit lipid peroxidation, thereby protecting metastatic cells from ferroptosis.
CONCLUSIONS
AADAC protects metastatic CRC cells from ferroptosis by inhibiting lipid peroxidation in an SLC7A11-dependent manner, thus effectively promoting their metastatic colonization and growth in the liver. Together, our findings suggest that AADAC can act as a prognostic indicator and potential therapeutic target for CRLM.
Topics: Amino Acid Transport System y+; Animals; Carboxylic Ester Hydrolases; Colorectal Neoplasms; Ferroptosis; Glutathione; Glutathione Disulfide; Lipid Peroxidation; Liver Neoplasms; Malondialdehyde; Mice; NF-E2-Related Factor 2; Reactive Oxygen Species
PubMed: 36163032
DOI: 10.1186/s13046-022-02493-0 -
Medical Archives (Sarajevo, Bosnia and... Jun 2022Presbycusis is a gradual hearing loss caused by the ageing process. This is a chronic condition that affects the elderly population, and sensorineural progressive...
BACKGROUND
Presbycusis is a gradual hearing loss caused by the ageing process. This is a chronic condition that affects the elderly population, and sensorineural progressive bilateral symmetry occurs with predominantly high-frequency hearing loss. The ability to discriminate speech decreases; hence, most of the affected patients have conversation problems, especially in noisy environments.This situation is a serious problem among elderly individuals. Social isolation, depression, and paranoia can be related to presbycusis.
OBJECTIVE
The aim of this study was to investigate GPx and the GSH:GSSG ratio as risk factors for presbycusis.
METHODS
A case-control study was conducted to determine the role of GPx activity with the GSH:GSSG ratio as a presbycusis risk factor in 60 subjects aged 55 to 75 years old during the period of August 2012 - April 2014. All of the subjects passed an ENT examination, pure tone audiometry, and tympanometry. The activity of GPx was measured with the Paglia and Valentine method, and the GSH:GSSG ratio was measured by the calorimetric method.
RESULTS
The activity of GPx and the GSH:GSSG ratio were significantly different between the groups (p<0.05), and the odds ratio for high GPx with a low GSH:GSSG ratio was 135 (CI 95%: 5.17-20,028.88).
CONCLUSION
High GPx activity with a low GSH:GSSG ratio is a risk factor for presbycusis.
Topics: Aged; Case-Control Studies; Disulfides; Glutathione; Glutathione Disulfide; Glutathione Peroxidase; Glutathione Reductase; Humans; Middle Aged; Peroxides; Presbycusis
PubMed: 36200118
DOI: 10.5455/medarh.2022.76.209-214 -
Food Chemistry Aug 2022A fast, sensitive and reproducible method using LC-MS/MS for simultaneous quantification of glutathione (GSH), glutathione disulfide (GSSG) and glutathione-S-sulfonate...
A fast, sensitive and reproducible method using LC-MS/MS for simultaneous quantification of glutathione (GSH), glutathione disulfide (GSSG) and glutathione-S-sulfonate (GSSOH) was developed, optimised and applied in analysis of grape juice and wine samples. The results show that only GSH (10-60 mg·L) and GSSG (2-11 mg·L) are found in grape juice when SO is not added. GSSOH was detected in must samples treated with SO but only at a low concentration (<1 mg L). In the wine samples, the dominant form of glutathione was GSSOH (5-11 mg L), followed by GSH (0-5 mg L) and GSSG (0-6 mg L), underscoring the importance of GSSOH quantification. GSSOH formation in wine was correlated with the total SO level in the wine. We believe this is the first report on GSSOH quantification in wine.
Topics: Chromatography, Liquid; Glutathione; Glutathione Disulfide; Tandem Mass Spectrometry; Vitis; Wine
PubMed: 35509159
DOI: 10.1016/j.foodchem.2022.132756 -
BMC Pediatrics Jul 2017Glucose-6-phosphate dehydrogenase (G6PD) deficiency is commonly detected during mass screening for neonatal disease. We developed a method to measure reduced glutathione...
BACKGROUND
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is commonly detected during mass screening for neonatal disease. We developed a method to measure reduced glutathione (GSH) and glutathione disulfide (GSSG) using tandem mass spectrometry (MS/MS) for detecting G6PD deficiency.
METHODS
The concentration of GSH and the GSH/GSSG ratio in newborn dry-blood-spot (DBS) screening and in blood plus sodium citrate for test confirmation were examined by MS/MS using labeled glycine as an internal standard.
RESULTS
G6PD-deficient newborns had a lower GSH content (242.9 ± 15.9 μmol/L)and GSH/GSSG ratio (14.9 ± 7.2) than neonatal controls (370.0 ± 53.2 μmol/L and 46.7 ± 19.6, respectively). Although the results showed a significance of P < 0.001 for DBS samples plus sodium citrate that were examined the first day after preparation, there were no significant differences in the mean GSH concentration and GSH/GSSG ratio between the G6PD deficiency-positive and negative groups when examined three days after sample preparation.
CONCLUSION
The concentration of GSH and the ratio of GSH/GSSG in blood measured using MS/MS on the first day of sample preparation are consistent with G6PD activity and are helpful for diagnosing G6PD deficiency.
Topics: Biomarkers; Case-Control Studies; Dried Blood Spot Testing; Glucosephosphate Dehydrogenase Deficiency; Glutathione; Glutathione Disulfide; Humans; Infant, Newborn; Neonatal Screening; Tandem Mass Spectrometry
PubMed: 28728551
DOI: 10.1186/s12887-017-0920-y -
Free Radical Research Aug 2008Apoptosis or programmed cell death represents a physiologically conserved mechanism of cell death that is pivotal in normal development and tissue homeostasis in all... (Review)
Review
Apoptosis or programmed cell death represents a physiologically conserved mechanism of cell death that is pivotal in normal development and tissue homeostasis in all organisms. As a key modulator of cell functions, the most abundant non-protein thiol, glutathione (GSH), has important roles in cellular defense against oxidant aggression, redox regulation of proteins thiols and maintaining redox homeostasis that is critical for proper function of cellular processes, including apoptosis. Thus, a shift in the cellular GSH-to-GSSG redox balance in favour of the oxidized species, GSSG, constitutes an important signal that could decide the fate of a cell. The current review will focus on three main areas: (1) general description of cellular apoptotic pathways, (2) cellular compartmentation of GSH and the contribution of mitochondrial GSH and redox proteins to apoptotic signalling and (3) role of redox mechanisms in the initiation and execution phases of apoptosis.
Topics: Animals; Apoptosis; Caspases; Glutathione; Glutathione Disulfide; Humans; Mitochondria; Oxidative Stress; Signal Transduction
PubMed: 18671159
DOI: 10.1080/10715760802317663 -
Free Radical Research Nov 2011The intestinal tract, known for its capability for self-renew, represents the first barrier of defence between the organism and its luminal environment. The... (Review)
Review
The intestinal tract, known for its capability for self-renew, represents the first barrier of defence between the organism and its luminal environment. The thiol/disulfide redox systems comprising the glutathione/glutathione disulfide (GSH/GSSG), cysteine/cystine (Cys/CySS) and reduced and oxidized thioredoxin (Trx/TrxSS) redox couples play important roles in preserving tissue redox homeostasis, metabolic functions, and cellular integrity. Control of the thiol-disulfide status at the luminal surface is essential for maintaining mucus fluidity and absorption of nutrients, and protection against chemical-induced oxidant injury. Within intestinal cells, these redox couples preserve an environment that supports physiological processes and orchestrates networks of enzymatic reactions against oxidative stress. In this review, we focus on the intestinal redox and antioxidant systems, their subcellular compartmentation, redox signalling and epithelial turnover, and contribution of luminal microbiota, key aspects that are relevant to understanding redox-dependent processes in gut biology with implications for degenerative digestive disorders, such as inflammation and cancer.
Topics: Cysteine; Cystine; Glutathione; Glutathione Disulfide; Humans; Intestinal Mucosa; Intestines; Oxidation-Reduction; Oxidative Stress; Signal Transduction; Thioredoxins
PubMed: 21831010
DOI: 10.3109/10715762.2011.611509 -
Molecular Genetics and Metabolism Jun 2022Phenylalanine hydroxylase (PAH) deficient phenylketonuria (PKU) is rightfully considered the paradigm treatable metabolic disease. Dietary substrate restriction (i.e.... (Review)
Review
Phenylalanine hydroxylase (PAH) deficient phenylketonuria (PKU) is rightfully considered the paradigm treatable metabolic disease. Dietary substrate restriction (i.e. phenylalanine (Phe) restriction) was applied >60 years ago and remains the primary PKU management means. The traditional model of PKU neuropathophysiology dictates blood Phe over-representation directs asymmetric blood:brain barrier amino acid transport through the LAT1 transporter with subsequent increased cerebral Phe concentration and low concentrations of tyrosine (Tyr), tryptophan (Trp), leucine (Leu), valine (Val), and isoleucine (Ile). Low Tyr and Trp concentrations generate secondary serotonergic and dopaminergic neurotransmitter paucities, widely attributed as drivers of PKU neurologic phenotypes. White matter disease, a central PKU characteristic, is ascribed to Phe-mediated tissue toxicity. Impaired cerebral protein synthesis, by reduced concentrations of non-Phe large neutral amino acids, is another cited pathological mechanism. The PKU amino acid transport model suggests Phe management should be more efficacious than is realized, as even early identified, continuously treated patients that retain therapy compliance into adulthood, demonstrate neurologic disease elements. Reduced cerebral metabolism was an early-recognized element of PKU pathology. Legacy data (late 1960's to mid-1970's) determined the Phe catabolite phenylpyruvate inhibits mitochondrial pyruvate transport. Respirometry of Pah cerebral mitochondria have attenuated respiratory chain complex 1 induction in response to pyruvate substrate, indicating reduced energy metabolism. Oxidative stress is intrinsic to PKU and Pah brain tissue presents increased reactive oxygen species. Phenylpyruvate inhibits glucose-6-phosphate dehydrogenase that generates reduced niacinamide adenine dinucleotide phosphate the obligatory cofactor of glutathione reductase. Pah brain tissue metabolomics identified increased oxidized glutathione and glutathione disulfide. Over-represented glutathione disulfide argues for reduced glutathione reductase activity secondary to reduced NADPH. Herein, we review evidence of energy and oxidative stress involvement in PKU pathology. Data suggests energy deficit and oxidative stress are features of PKU pathophysiology, providing intervention-amenable therapeutic targets to ameliorate disease elements refractory to standard of care.
Topics: Adult; Glutathione Disulfide; Glutathione Reductase; Humans; Oxidative Stress; Phenylalanine; Phenylalanine Hydroxylase; Phenylketonurias; Pyruvates; Tyrosine
PubMed: 35379539
DOI: 10.1016/j.ymgme.2022.03.012 -
Redox Biology Aug 2016At its core mitochondrial function relies on redox reactions. Electrons stripped from nutrients are used to form NADH and NADPH, electron carriers that are similar in... (Review)
Review
At its core mitochondrial function relies on redox reactions. Electrons stripped from nutrients are used to form NADH and NADPH, electron carriers that are similar in structure but support different functions. NADH supports ATP production but also generates reactive oxygen species (ROS), superoxide (O2(·-)) and hydrogen peroxide (H2O2). NADH-driven ROS production is counterbalanced by NADPH which maintains antioxidants in an active state. Mitochondria rely on a redox buffering network composed of reduced glutathione (GSH) and peroxiredoxins (Prx) to quench ROS generated by nutrient metabolism. As H2O2 is quenched, NADPH is expended to reactivate antioxidant networks and reset the redox environment. Thus, the mitochondrial redox environment is in a constant state of flux reflecting changes in nutrient and ROS metabolism. Changes in redox environment can modulate protein function through oxidation of protein cysteine thiols. Typically cysteine oxidation is considered to be mediated by H2O2 which oxidizes protein thiols (SH) forming sulfenic acid (SOH). However, problems begin to emerge when one critically evaluates the regulatory function of SOH. Indeed SOH formation is slow, non-specific, and once formed SOH reacts rapidly with a variety of molecules. By contrast, protein S-glutathionylation (PGlu) reactions involve the conjugation and removal of glutathione moieties from modifiable cysteine residues. PGlu reactions are driven by fluctuations in the availability of GSH and oxidized glutathione (GSSG) and thus should be exquisitely sensitive to changes ROS flux due to shifts in the glutathione pool in response to varying H2O2 availability. Here, we propose that energy metabolism-linked redox signals originating from mitochondria are mediated indirectly by H2O2 through the GSH redox buffering network in and outside mitochondria. This proposal is based on several observations that have shown that unlike other redox modifications PGlu reactions fulfill the requisite criteria to serve as an effective posttranslational modification that controls protein function.
Topics: Animals; Energy Metabolism; Glutathione; Glutathione Disulfide; Humans; Hydrogen Peroxide; Mitochondria; NADP; Oxidation-Reduction; Oxidative Stress; Protein Processing, Post-Translational; Reactive Oxygen Species; Signal Transduction
PubMed: 26773874
DOI: 10.1016/j.redox.2015.12.010 -
Molecules (Basel, Switzerland) May 2021Phosphorus species are potent modulators of physicochemical and bioactive properties of peptide compounds. O,O-diorganyl dithiophoshoric acids (DTP) form bioactive salts...
Phosphorus species are potent modulators of physicochemical and bioactive properties of peptide compounds. O,O-diorganyl dithiophoshoric acids (DTP) form bioactive salts with nitrogen-containing biomolecules; however, their potential as a peptide modifier is poorly known. We synthesized amphiphilic ammonium salts of O,O-dimenthyl DTP with glutathione, a vital tripeptide with antioxidant, protective and regulatory functions. DTP moiety imparted radical scavenging activity to oxidized glutathione (GSSG), modulated the activity of reduced glutathione (GSH) and profoundly improved adsorption and electrooxidation of both glutathione salts on graphene oxide modified electrode. According to NMR spectroscopy and GC-MS, the dithiophosphates persisted against immediate dissociation in an aqueous solution accompanied by hydrolysis of DTP moiety into phosphoric acid, menthol and hydrogen sulfide as well as in situ thiol-disulfide conversions in peptide moieties due to the oxidation of GSH and reduction of GSSG. The thiol content available in dissolved GSH dithiophosphate was more stable during air oxidation compared with free GSH. GSH and the dithiophosphates, unlike DTP, caused a thiol-dependent reduction of MTS tetrazolium salt. The results for the first time suggest O,O-dimenthyl DTP as a redox modifier for glutathione, which releases hydrogen sulfide and induces biorelevant redox conversions of thiol/disulfide groups.
Topics: Antioxidants; Disulfides; Gas Chromatography-Mass Spectrometry; Glutathione; Glutathione Disulfide; Magnetic Resonance Spectroscopy; Oxidation-Reduction; Oxidative Stress; Phosphates; Sulfhydryl Compounds
PubMed: 34067789
DOI: 10.3390/molecules26102973