Peroxiredoxins (Prx's) are a superfamily of peroxidases that are ubiquitous in all super-kingdoms. Previous biochemical and structural studies have suggested that Prx's could be divided into five subfamilies (1-Cys, Typical 2-Cys, Atypical 2-Cys C-, L- and R- types). In this work, we have developed a set of regular expression patterns describing subfamily-specific spatial constraints of the key catalytic residues. Using these patterns, 1,016 Prx's available in public databases were classified into the five subfamilies. Our method performed well for most of the types except for Atypical 2 Cys R type.
Classification* ; Peroxidases ; Peroxiredoxins*

BACKGROUND: Peroxiredoxin(Prx) is a novel peroxidase family to remove hydrogen peroxide using thioredoxin system, which is consisted of thioredoxin, thioredoxin reductase and NADPH. Several enzymatic antioxidants, such as superoxide dismutase, catalase and peroxidases are known to be present in the normal skin. But very little is known on the expression of Prx in the normal skin. OBJECTIVE: The aim of this study was to evaluate the expression of Prx isotypes in the normal human and rat skin, and thus to understand the role of Prx in the skin. MATERIALS AND METHODS: In this study, expression of 5 isotypes of Prx was evaluated in the primary cultures of keratinocytes and fibroblasts from human and rat, HaCaT cells and A431 cells by Western blot analysis. Also, immunohistochemical study for Prx I-IV expression was performed in the rat fibroblasts. RESULTS: Western blot analysis provided strong signals for Prx I, II and III with the cell extracts of cultured cells from the human and rat. The signals for Prx IV were weakly positive in hK, A431, hF and rF. The signals for Prx VI were positive in human cells, but were negative in rat cells. The finding were also identified in the intact skin. From immunocytochemical study for Prx I-IV, they were stained positively as a reticulated pattern in the cytoplasm of rF without isotype-specific difference. The positive reaction was strong in perinuclear cytoplasm. CONCLUSIONS: This study shows that Prx is ubiquitously expressed in the normal human and rat skin with an isotype-specific expression by species and cell types.
Animals ; Antioxidants ; Blotting, Western ; Catalase ; Cell Extracts ; Cells, Cultured* ; Cytoplasm ; Fibroblasts ; Humans* ; Hydrogen Peroxide ; Keratinocytes ; NADP ; Peroxidase ; Peroxidases ; Peroxiredoxins* ; Rats* ; Skin* ; Superoxide Dismutase ; Thioredoxin-Disulfide Reductase ; Thioredoxins

Objective To investigate the relationship between the expression of glutathione peroxidase(GPX)genes and the clinical prognosis in glioma patients,and to construct and evaluate the model for predicting the prognosis of glioma. Methods The clinical information and GPX expression of 663 patients,including 153 patients of glioblastoma(GBM)and 510 patients of low-grade glioma(LGG),were obtained from The Cancer Genome Atlas(TCGA)database.The relationship between GPX expression and patient survival was analyzed.The key GPX affecting the prognosis of glioma was screened out by single- and multi-factor Cox's proportional-hazards regression models and validated by least absolute shrinkage and selection operator(Lasso)regression.Finally,we constructed the model for predicting the prognosis of glioma with the screening results and then used concordance index and calibration curve respectively to evaluate the discrimination and calibration of model. Results Compared with those in the control group,the expression levels of GPX1,GPX3,GPX4,GPX7,and GPX8 were up-regulated in glioma patients(all P<0.001).Moreover,the expression levels of other GPX except GPX3 were higher in GBM patients than in LGG patients(all P<0.001).The Kaplan-Meier curves showed that the progression-free survival of GBM with high expression of GPX1(P=0.013)and GPX4(P=0.040),as well as the overall survival,disease-specific survival,and progression-free survival of LGG with high expression of GPX1,GPX7,and GPX8,was shortened(all P<0.001).GPX7 and GPX8 were screened out as the key factors affecting the prognosis of LGG.The results were further used to construct a nomogram model,which suggested GPX7 was the most important variable.The concordance index of the model was 0.843(95%CI=0.809-0.853),and the calibration curve showed that the predicted and actual results had good consistency. Conclusion GPX7 is an independent risk factor affecting the prognosis of LGG,and the nomogram model constructed with it can be used to predict the survival rate of LGG.
Brain Neoplasms ; Glioblastoma ; Glioma/diagnosis* ; Glutathione Peroxidase/metabolism* ; Humans ; Peroxidases ; Prognosis ; Proportional Hazards Models

OBJECTIVETo study the effect of drought stress on the changes of physiological adaptation of Atractylodes lancea seedlings.

METHODInvestigation was carried out on content changes of MDA, soluble protein, and activities of SOD, POD, CAT, APX in A. lancea seedlings under polyethylene glycol (PEG-6000)-simulated drought stress.

RESULTIn A. lancea seedlings treated with 15% and 25% PEG, the content of MDA increased significantly with the stress time, and increased more significantly at a higher concentration of PEG. The content of soluble protein increased significantly after treatment on the day one and day three; activities of SOD, POD, CAT and APX increased at first and decreased later, increasing rates rose at high concentration of PEG moreover, activities of POD, APX reached the maximum after three days, and the time of maximum activities changed with concentration of PEG.

CONCLUSIONA. lancea seedlings adapted to drought stress by increasing the content of soluble protein to decrease water potential, and by improving activities of protective enzymes to enhance anti-oxidative ability under drought stress.

Adaptation, Physiological ; physiology ; Ascorbate Peroxidases ; Atractylodes ; enzymology ; metabolism ; physiology ; Catalase ; metabolism ; Droughts ; Gene Expression Regulation, Plant ; physiology ; Peroxidase ; metabolism ; Peroxidases ; metabolism ; Seedlings ; enzymology ; metabolism ; physiology ; Superoxide Dismutase ; metabolism

Previous studies have shown that inhibitory synaptic inputs are different between in spinal and trigeminal motor systems and activities of jaw closing and opening alpha motoneurons are different during a chewing cycle. This study examined the distribution of inhibitory synapses made on masseter and digastric motoneurons by using retrograde tracing of wheat germ agglutinin conjugated to horseradish peroxides (WGA-HRP) combined with postembedding immunogold labeling on serial ultrathin sections.Many boutons IR (immunoreactive) to GABA and/or glycine were found to appose on two kinds of motoneurons, which were containing pleomorphic vesicles (a mixture of round, oval and flattened vesicles) and exhibited symmetrical synaptic contacts on the somata. Packing density and synaptic covering % were higher in digastric than in masseter motoneurons. Of 703 boutons apposing on 12 masseter motoneurons, 6.08+/-3.51, 29.67+/-8.89 and 17.78+/-5.22% were IR to GABA only, glycine only, and both GABA and glycine, respectively. Of 637 boutons apposing on 11 digastric motoneurons, 6.37+/-4.64, 19.74+/-8.25 and 12.01+/-5.38% were IR to GABA only, glycine only, and both GABA and glycine, respectively. Proportions of glycine IR boutons were higher than that of GABA IR boutons in both masseter and digastric motoneurons. Packing density and proportion of boutons IR to GABA and/or glycine were higher in jaw closing than in jaw opening motoneurons (packing density, 12.03+/-1.58 vs 10.28+/-2.99; proportion of IR boutons, 53.54+/-8.94% vs 38.12+/-9.38% in jaw closing and opening motoneurons, respectively). These results provide ultrastructural evidence that GABA and glycine act as important neurotransmitters for modulation of jaw movement and that proportion of inhibitory synapses is higher in jaw closing than in jaw opening motoneurons.
Animals ; Armoracia ; gamma-Aminobutyric Acid ; Glycine ; Jaw ; Mastication ; Neurotransmitter Agents ; Peroxides ; Rats* ; Synapses ; Triticum ; Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate

The distribution of GABA and/or glycine like immunoreactive nerve terminals on the soma of the masseteric gamma motoneurons were investigated using retrograde tracing of WGA-HRP (wheat germ agglutinin conjugated horseradish peroxidase) and postembedding immunogold labeling methods in serial ultrathin sections. Quantitative analysis of 140 nerve terminals apposing on somata of gamma motoneuron size less than 21 mm in average diameter was performed. The results obtained were as follows. 1. Synaptic covering % of apposing nerve terminals was 21.45+/-11.48% and packing density was 12.85+/-6.17. 2. Nerve terminals immunoreactive (IR) to GABA or glycine were F type containing pleomorphic vesicles with round shape predominant. Majority of nerve terminals immunonegative to GABA or glycine were S type containing spherical vesicles and few of them were F type. 3. 11.42+/-10.00% of examined nerve terminals were IR to GABA only, and 12.71+/-9.85% were IR to GABA and glycine, and 15.21+/-9.58% were IR to glycine only. 4. Synaptic covering % of nerve terminals IR to glycine only was highest (4.58+/-4.50%), followed in order by GABA and glycine (3.18+/-2.77%), and GABA only (2.38+/-2.06%). 5. Among all terminals, immunonegative nerve terminals (60.66+/-14.65%) were much more than nerve terminals immunoreactive to GABA and/or glycine (39.34+/-14.65%) These results show that inhibitory synaptic input and synaptic organization of the masseteric gamma motoneurons reveal characteristic features in contrast to that of alpha motoneurons and which may correlated to the electrophysi-ological characteristics of masseteric gamma motoneurons.
Animals ; Armoracia ; Carisoprodol ; gamma-Aminobutyric Acid* ; Glycine* ; Jaw* ; Presynaptic Terminals* ; Rats* ; Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate

Atherosclerotic vascular dysfunction is a chronic inflammatory process that spreads from the fatty streak and foam cells through lesion progression. Therefore, its early diagnosis and prevention is unfeasible. Reactive oxygen species (ROS) play important roles in the pathogenesis of atherosclerotic vascular disease. Intracellular redox status is tightly regulated by oxidant and antioxidant systems. Imbalance in these systems causes oxidative or reductive stress which triggers cellular damage or aberrant signaling, and leads to dysregulation. Paradoxically, large clinical trials have shown that non-specific ROS scavenging by antioxidant vitamins is ineffective or sometimes harmful. ROS production can be locally regulated by cellular antioxidant enzymes, such as superoxide dismutases, catalase, glutathione peroxidases and peroxiredoxins. Therapeutic approach targeting these antioxidant enzymes might prove beneficial for prevention of ROS-related atherosclerotic vascular disease. Conversely, the development of specific antioxidant enzyme-mimetics could contribute to the clinical effectiveness.
Atherosclerosis ; Catalase ; Early Diagnosis ; Foam Cells ; Glutathione ; Oxidation-Reduction ; Peroxidases ; Peroxiredoxins ; Reactive Oxygen Species ; Superoxides ; Vascular Diseases* ; Vitamins

BACKGROUND: Peroxidases (Prx) of the peroxiredoxin family reduce hydrogen peroxide and alkyl hydroperoxides to water and alcohol respectively. Hydrogen peroxide is implicated as an intracellular messenger in various cellular responses such as proliferation and differentiation. And Prx I activity is regulated by Cdc-2 mediated phosphorylation. This work was undertaken to investigate the proliferation role of peroxiredoxin III as a member of Prx family in Prx III overexpressed HeLa cell line. METHODS: To provide further evidence of proliferation, we selected Prx III stably expressed HeLa Tet-off cell lines. Cell proliferation was examined by using proliferation reagent WST-1 in the presence or absence of doxycycline. Prx III, 2-cys Prx enzymes exist as homodimer. The activation of Prx III heterodimer with induced and endogenous Prx III was examined by immunoprecipitation. RESULTS: Immunoprecipitation analysis of the induced and endogenous Prx III with anti-myc showed that the induced wild type (WT) and dominant negative (DN) Prx III from HeLa Prx III Tet-off stable cell heterodimerized with endogenous Prx III each other. And the expression level of induced Prx III was examined after addition of doxycycline. By 72 hr, the expression level of induced Prx III was diminished gradually and the half-life of the induced wild type Prx III was approximately 17 hr. The proliferation experiment demonstrated that the relative proliferation value of induced and endogenous WT Prx III stable cell has no changes but the DN Prx III induced HeLa Tet-off stable cells were lower than endogenous Prx III. CONCLUSION: In conclusion, the HeLa dominant negative Prx III Tet-off stable cells were decreased the proliferation.
Cell Line ; Cell Proliferation ; Doxycycline ; Half-Life ; HeLa Cells* ; Humans* ; Hydrogen Peroxide ; Immunoprecipitation ; Peroxidases ; Peroxiredoxin III* ; Peroxiredoxins* ; Phosphorylation

The origin of sympathetic and sensory nerves innervating heart in the cat was investigated using HRP (Horseradish peroxidase) and WGA-HRP (Wheat germ agglutinin-horseradish peroxidase) as neuronal tracers. The neural tracers were injected into subepicardial layer and myocardium of the right atrium, left atrium, right ventricle and left ventricle, respectively. Labeled sympathetic neuronal cell bodies were found in superior cervical ganglia, middle cervical ganglia, stellate ganglia and 4th and 5th thoracic ganglia, mainly in middle cervical ganglia and stellate ganglia. Heavier labeled neuronal cell bodies were found in the middle cervical ganglia and stellate ganglia when the neural tracers were injected into left atrium, right ventricle and left ventricle. Labeled sensory neuronal cell bodies were found in nodose ganglia and T1-T6 spinal ganglia, mainly in T1-T5 spinal ganglia. Heavier labeled neuronal cell bodies were found in the nodose ganglia when the neural tracers were injected into left atrium and right ventricle. These results may provide a neuroanatomical data on origin of sensory nerves innervating the heart of the cat.
Animals ; Cats* ; Ganglia ; Ganglia, Sensory ; Ganglia, Spinal ; Ganglia, Sympathetic ; Heart Atria ; Heart Ventricles ; Heart* ; Horseradish Peroxidase ; Myocardium ; Neurons* ; Nodose Ganglion ; Sensory Receptor Cells ; Stellate Ganglion ; Superior Cervical Ganglion ; Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate*

PURPOSE: Ferroptosis is a new mode of regulated cell death, which is completely distinct from other cell death modes based on morphological, biochemical, and genetic criteria. This study evaluated the therapeutic role of ferroptosis in classic chemotherapy drugs, including the underlying mechanism. MATERIALS AND METHODS: Cell viabilitywas detected by using the methylthiazoltetrazlium dye uptake method. RNAiwas used to knockout iron-responsive element binding protein 2, and polymerase chain reaction, western blot was used to evaluate the efficiency. Intracellular reduced glutathione level and glutathione peroxidases activitywere determined by related assay kit. Intracellularreactive oxygen species levelswere determined by flowcytometry. Electron microscopywas used to observe ultrastructure changes in cell. RESULTS: Among five chemotherapeutic drugs screened in this study, cisplatin was found to be an inducer for both ferroptosis and apoptosis in A549 and HCT116 cells. The depletion of reduced glutathione caused by cisplatin and the inactivation of glutathione peroxidase played the vital role in the underlying mechanism. Besides, combination therapy of cisplatin and erastin showed significant synergistic effect on their anti-tumor activity. CONCLUSION: Ferroptosis had great potential to become a new approach in anti-tumor therapies and make up for some classic drugs, which open up a new way for their utility in clinic.
Apoptosis ; Blotting, Western ; Carrier Proteins ; Cell Death ; Cisplatin* ; Drug Therapy ; Glutathione ; Glutathione Peroxidase ; HCT116 Cells ; Methods ; Oxygen ; Peroxidases ; Polymerase Chain Reaction