Mechanism Of Glutathione Research Articles

Characteristics and mechanism of Glutathione in inhibiting coal spontaneous combustion

Inhibitors play an important role in preventing and controlling coal spontaneous combustion (CSC). In this study, the inhibitory effects of antioxidant-reduced glutathione (G-SH) on CSC were examined. Thermogravimetric-differential scanning calorimetry (TG-DSC), cross-point temperature (CPT), and oxidation product tests were used to examine the effect of G-SH on the tendency of CSC and compare the discrepancy in the inhibition effect of G-SH and the halogen inhibitor. The changes in the free radical type, concentration, and surface functional groups in coal before and after the addition of G-SH were analyzed using electron spin resonance spectroscopy (ESR) and Fourier transform infrared spectroscopy (FT-IR). Six common active radical models were constructed, and the thermodynamic parameters of the reaction were calculated using density functional theory (DFT). The results revealed that G-SH inhibits the spontaneous combustion of coal. The inhibitory effect of G-SH was significantly stronger than that of the halogen salt inhibitors CaCl2 and MgCl2, and the higher the concentration of G-SH, the stronger is the inhibitory effect. The characteristic temperature points in the thermogravimetric experiment of coal samples with G-SH shifted to a higher temperature zone, and the CO concentration and oxygen consumption were lower than those of raw coal. After G-SH treatment, the type and relative concentration of free radicals in coal were lower than those in raw coal, the content of aliphatic hydrocarbon functional groups and oxygen-containing functional groups decreased, and the content of sulfur-containing functional groups increased. According to the calculation of Gibbs free energy and reaction enthalpy, G-SH can effectively neutralize the active free radicals in the process of coal oxidation, and the reaction activity with the free radicals in the process of coal oxidation is ·OOH > ·OH > ·CH3 > RO· > R· > ROO·. According to the experimental results, it is inferred that G-SH continuously supplies a large number of hydrogen donors (·H) for the reaction during the oxidation process and simultaneously neutralizes carbon free radicals and carbon oxygen free radicals, thereby reducing the concentration and reactivity of free radicals in the whole chain reaction process and blocking the occurrence of coal-oxygen composite reaction.

Glutathione improves testicular spermatogenesis through inhibiting oxidative stress, mitochondrial damage, and apoptosis induced by copper deposition in mice with Wilson disease

Background and objectiveThere are considerable evidence of reproductive impairment in male organisms with Wilson disease (WD). The purpose of this study was to observe spermatogenesis, mitochondrial damage, apoptosis, and the level of oxidative stress in the testes of Wilson disease model TX mice, and to observe the effect and mechanism of glutathione on testicular spermatogenesis. MethodsMice were divided into a normal control group (control group), Wilson disease model TX mice group (WD group), penicillamine-treated TX mice group (penicillamine group) and glutathione-treated TX mice group (glutathione group). Testicular coefficient, histomorphology of testis and epididymis, number of spermatozoa, apoptosis of spermatogenic cells and expression of apoptosis-related proteins were observed. Ultrastructural analysis of mitochondria and mitochondrial membrane potential (MMP) monitored using JC-1 dye were used to detect mitochondrial damage. The levels of malondialdehyde (MDA), glutathione (GSH), catalase (CAT), and reactive oxygen species (ROS) in testicular cells were measured to assess oxidative stress. ResultsTesticular coefficient did not change in mice with Wilson disease. However, the tissue structure of the testicular seminiferous tubules was damaged, and the number of spermatozoa in the epididymal lumen was significantly reduced in WD group. The apoptosis rate in the testes was significantly increased. The protein expression of the pro-apoptotic proteins Bax and Caspase-3 significantly increased, and the expressions of the anti-apoptotic protein Bcl-2 significantly decreased. The levels of ROS and MDA significantly increased, and the levels of CAT and GSH significantly decreased. Mitochondria with abnormal ultrastructure and the rate of JC-1 positive cells were significantly increased in the WD group. After copper chelation by penicillamine, the structure of the testicular seminiferous tubules and the number of spermatozoa in the epididymal lumen were significantly improved. The number of apoptotic cells was significantly reduced. The levels of Bax and Caspase-3 decreased, and the expression of Bcl-2 increased. The contents of CAT and GSH increased, and the levels of ROS and MDA decreased significantly. The abnormal mitochondria and JC-1 positive cells was significantly decreased. The histomorphology of seminiferous tubules, spermatogenic function, apoptosis rate, apoptosis-related proteins, mitochondrial damage, and oxidative stress in Wilson disease TX mice significantly improved after glutathione treatment. ConclusionCopper deposition in Wilson disease can lead to oxidative stress injury, mitochondrial damage, and apoptosis in the testis, leading to the impairment of spermatogenesis. Glutathione may improve testicular spermatogenesis in male Wilson disease TX mice by inhibiting copper deposition-induced oxidative stress, mitochondrial damage, and apoptosis.

Inhibition Kinetics and Mechanism of Glutathione and Quercetin on Acrylamide in the Low-Moisture Maillard Systems

The inhibition kinetics of glutathione (GSH) and quercetin on acrylamide (AA) formation in the low-moisture Maillard systems were investigated at 180°C. The inhibition rates in an equal-molar asparagine-glucose (Asn-Glc) system were higher than those in an asparagine-fructose (Asn-Fru) system, and the maximum inhibition rates for AA were 57.75% with 10-2 mol L-1 GSH and 51.38% with 10-1 mol L-1 quercetin. The Logistic-Index dynamic model and two consecutive simplified first-order kinetic models were well fitted to the changes of AA in the Asn-Glc system. The kinetics results suggested that the predominant inhibition effect of GSH on AA could be attributed to the competitive reaction between GSH and Asn for the consumption of Glc. The kinetic results and high-pressure liquid chromatography-tandem mass spectrometry analysis of the inhibitory effect of quercetin on AA indicated that quercetin might mitigate AA through the binding reaction of quercetin decomposition products and Maillard intermediate products. These experimental results provide theoretical data that may be useful to control the formation of AA during food thermal processing.

Ectomycorrhizal Fungi and Its Role in Metal Homeostasis through Metallothionein and Glutathione Mechanisms

Ectomycorrhizal Fungi and Its Role in Metal Homeostasis through Metallothionein and Glutathione Mechanisms

Effects of olive mill wastewaters on total DNA and gene expressions of heat shock proteins, antioxidant enzymes and glutathione mechanisms in Sunflower plants

Effects of olive mill wastewaters on total DNA and gene expressions of heat shock proteins, antioxidant enzymes and glutathione mechanisms in Sunflower plants

Endogenic oxidative stress response contributes to glutathione over-accumulation in mutant Saccharomyces cerevisiae Y518.

Mechanisms of glutathione (GSH) over-accumulation in mutant Saccharomyces cerevisiae Y518 screened by ultraviolet and nitrosoguanidine-induced random mutagenesis were studied. Y518 accumulated higher levels of GSH and L-cysteine than its wild-type strain. RNA-Seq and pathway enrichment analysis indicated a difference in the expression of key genes involved in cysteine production, the GSH biosynthesis pathway, and antioxidation processes. GSH1, MET17, CYS4, GPX2, CTT1, TRX2, and SOD1 and the transcriptional activators SKN7 and YAP1 were up-regulated in the mutant. Moreover, Y518 showed a dysfunctional respiratory chain resulting from dramatically weakened activity of complex III and significant elevation of intracellular reactive oxygen species (ROS) levels. The supplementation of antimycin A in the culture of the parent strain showed equivalent changes of ROS and GSH level. This study indicates that defective complex III prompts abundant endogenic ROS generation, which triggers an oxidative stress response and upregulation of gene expression associated with GSH biosynthesis. This finding may be helpful for developing new strategies for GSH fermentation process optimization or metabolic engineering.

The mechanism of Glutathione in the prevention of ventilator-associated lung injury

Objective To investigate the mechanism of Glutathione in the prevention of ventilator-associated lung injury. Methods 30 mechanical ventilation patients who were healthy before were selected and randomly divided into the two groups. Group A was the high tidal volume group:10mL/kg;group B was used the tidal volume plus the injection of Glutathione(2.4g/d). After 48 hours,we collected lavage fluid and use Coomassie brilliant blue to detect the protein content of alveolar lavage fluid of the two groups. Results There was a significant difference(P<0.01) between the two groups. The protein content in group A[(9.90±2.25)g/L]was higher than that of group B[(4.17± 0.39)g/L],and there was statistically significant(P<0.01). Conclusion Glutathione can reduce the incidence of ventilator-associated lung injury and prevent the occurrence of ventilator-associated lung injury. Key words: Glutathione; Ventilator-associated lung injury; Mechanical ventilation

Glutathione Supplementation Attenuates Oxidative Stress and Improves Vascular Hyporesponsiveness in Experimental Obstructive Jaundice.

We investigated the protective effects and mechanism of glutathione (GSH) on vascular hyporesponsiveness induced by bile duct ligation (BDL) in a rat model. Seventy-two male Sprague-Dawley rats were randomly divided into four groups: a NS group, a GSH group, a BDL + NS group, and a BDL + GSH group. GSH was administrated into rats in the GSH and BDL + GSH groups by gastric gavage. An equal volume of normal saline was, respectively, given in the NS group and BDL + NS group. Blood was gathered for serological determination and thoracic aorta rings were isolated for measurement of isometric tension. Obstructive jaundice led to a significant increase in the serum total bilirubin, AST, and ALT levels. The proinflammatory cytokines levels (TNF-α and IL-1β), concentration of NO, and oxidative stress markers (MDA and 3-NT) were increased as well. All of those were reduced by the treatment of GSH. Meanwhile, contraction of aorta rings to NA and vasorelaxation to ACh or SNP in the BDL group rats were markedly decreased, while GSH administration reversed this change. Our findings suggested that GSH supplementation attenuated overexpressed ONOO(−) from the reaction of excessive NO with O2 ∙- and protected against obstructive jaundice-induced vascular hyporesponsiveness in rats.

Role of glutathione and other antioxidants in the inhibition of apoptosis and mesenchymal transition in rabbit lens epithelial cells.

This study aimed to discuss the effect and mechanism of glutathione (GSH) and catalase (CAT) on transforming growth factor beta (TGF-β)-induced lens epithelial cell (LEC) apoptosis and epithelial mesenchymal transition (EMT) to prevent and control cataracts. Healthy rabbits (4 weeks old) were randomly selected, and LECs from their lenses were cultured in vitro. The 2nd- and 3rd-generation cells were divided into 6 groups (group A: 75 pg/mL TGF-β2; B: 75 pg/mL TGF-β2+10 mM GSH; C: 75 pg/mL TGF-β2+300 U/mL CAT; D: 10 mM GSH; E: 300 U/mL CAT; and F: control group). Cell morphology was observed under an inverted microscope. The gap between cells increased, and the cells became reticulate after adding 75 pg/mL TGF-β2; also, the cells swelled and appeared spindle-shaped. However, antioxidants reduced these changes. Growth inhibition was analyzed at 12, 24, and 48 h, and the differences between groups were not statistically significant. Cell apoptosis was analyzed, and the differences between group A and groups B and C were statistically significant (P<0.05). Reverse transcriptase-polymerase chain reaction was used to detect mRNA expression of α-SMA. The α-SMA mRNA level was greater in group A than in groups B and C (P<0.05). TGF-β2 inhibited LEC proliferation and induced apoptosis and EMT. GSH and CAT inhibited apoptosis and EMT in LECs, and they had little effect on cell proliferation. Reactive oxygen species may be involved in cell apoptosis and EMT induced by TGF-β2 as a cell-signaling molecule.

Oxidation of Glutathione by [FeIV(O)(N4Py)]2+: Characterization of an [FeIII(SG)(N4Py)]2+ Intermediate

The mechanism of glutathione (GSH) oxidation by a nonheme ferryl species has been investigated. The reaction of [Fe(IV)(O)(N4Py)](2+) (1) with GSH in an aqueous solution leads to the rapid formation of a green intermediate, characterized as the low-spin ferric complex [Fe(III)(SG)(N4Py)](2+) (2) by UV-vis and electron paramagnetic resonance spectroscopies and by high-resolution time-of-flight mass spectrometry. Intermediate 2 decays to form the final products [Fe(II)(OH(2))(N4Py)](2+) and the disulfide GSSG over time. The overall reaction was fit to a three-step process involving rapid quenching of the ferryl by GSH, followed by the formation and decay of 2, which are both second-order processes.

Effect of isoniazid on glutathione biosynthesis and degradation in Mycobacterium smegmatis.

The mechanism of glutathione (GSH) depletion by isoniazid (INH) was studied in M. smegmatis. INH increased the activity of gamma-glutamyl transferase (GGT) whether added before medium inoculation or to actively growing cells. The activity of GGT in cells grown from the beginning in INH-containing medium increased significantly on growth days 2-6. Three-day old M. smegmatis cells treated with INH exhibited a 30-65% increase in the activity of GGT. The activities of gamma-glutamyl-cysteine synthase (GGCS) and GSH synthase (GS) were lowered by 50 and 56% respectively on the second day of growth when M. smegmatis was grown in a medium supplemented with 1.5 mg INH per L. In 3-day old M. smegmatis, INH significantly inhibited the activities of GSH biosynthetic enzymes. The results demonstrate that the increased activity of GGT and decreased activities of GSH biosynthetic enzymes are responsible for GSH depletion by INH in M. smegmatis.