Major Antioxidant Enzymes Research Articles

Gochujang suppresses cell survival and changes reactive oxygen species metabolism in colorectal cancer cells.

There is a significant global increase in colorectal cancer (CRC) among young adults. Gochujang, one of the signature Korean traditional fermented foods, contains various bioactive compounds and has multiple health-beneficial effects, including anticancer effects; however, the detailed cellular and molecular mechanisms of its anticancer outcomes are not fully understood. The objective of the present study was to investigate the detailed underlying anticancer mechanisms of Gochujang in CRC cells. Gochujang was extracted with 80% ethanol, and total polyphenol contents (9.9 ± 1.63 mgGAE/g) and total flavonoid contents (0.14 ± 0.07 mgQE/g) of Gochujang extract (GE) were evaluated. GE significantly suppressed cell viability, migration, and colony formation in CRC cells. Also, GE increased the cell cycle arrest-related protein p21 level, whereas it decreased cell cycle progression-associated proteins, such as p-Rb. Moreover, GE markedly elevated the levels of proapoptotic proteins (e.g. Bim and c-PARP), while it downregulated antiapoptotic protein expressions (e.g. Bcl-2 and Bcl-xL). GE also altered the expression of the autophagy-involved proteins. Furthermore, GE strongly reduced the expression of major antioxidant enzymes and increased the reactive oxygen species (ROS) generation in CRC cells, causing an imbalance of ROS metabolism. In conclusion, this study demonstrated that Gochujang exerts anticancer effects in CRC cells by inhibiting cell proliferation, increasing cell death, and interrupting ROS metabolism.

Human anti-apoptotic Bcl-2 and Bcl-xL proteins protect yeast cells from aging induced oxidative stress

Aging is a degenerative, biological, and time-dependent process that affects all organisms. Yeast aging is a physiological phenomenon characterized by the progressive transformation of yeast cells, resulting in modifications to their viability and vitality. Aging in yeast cells is comparable to that in higher organisms in some respects; however, due to their straightforward and well-characterized genetic makeup, these cells present unique advantages when it comes to researching the aging process. Here, we assessed the impact of human anti-apoptotic Bcl-2 and Bcl-xL proteins on aging using a yeast model. The findings clearly showed that these proteins exhibited remarkable anti-aging properties in yeast cells. Our data indicate that the presence of both proteins enhanced the reproductive survival of aging cells, likely by effecting the components functioning as both pro- and anti-oxidants, depending on the stage of yeast cell lifespan. Both proteins partially protected yeast cells from aging-related morphological deformations and cellular damage during the aging period. In particular, Bcl-xL expressing yeast cells reached the maximum activity levels for almost all of the major antioxidant enzymes and the total antioxidant status on the 8th day of lifespan and could provide effective protection at the latest stage of the investigated aging period. The chemometric data analysis of IR spectra confirmed the findings of the morphological and biochemical analyses. In this regard, specifically, understanding the mechanism of action on the cellular redox state of Bcl-xL in yeast may facilitate comprehension of its indirect antioxidant function in higher eukaryotes.

Overexpression of Auxin/Indole-3-Acetic Acid Gene TrIAA27 Enhances Biomass, Drought, and Salt Tolerance in Arabidopsis thaliana

White clover (Trifolium repens L.) is an important forage and aesthetic plant species, but it is susceptible to drought and heat stress. The phytohormone auxin regulates several aspects of plant development and alleviates the effects of drought stress in plants, including white clover, by involving auxin/indole acetic acid (Aux/IAA) family genes. However, Aux/IAA genes and the underlying mechanism of auxin-mediated drought response remain elusive in white clover. To extend our understanding of the multiple functions of Aux/IAAs, the current study described the characterization of a member of the Aux/IAA family TrIAA27 of white clover. TrIAA27 protein had conserved the Aux/IAA family domain and shared high sequence similarity with the IAA27 gene of a closely related species and Arabidopsis. Expression of TrIAA27 was upregulated in response to heavy metal, drought, salt, NO, Ca2+, H2O2, Spm, ABA, and IAA treatments, while downregulated under cold stress in the roots and leaves of white clover. TrIAA27 protein was localized in the nucleus. Constitutive overexpression of TrIAA27 in Arabidopsis thaliana led to enhanced hypocotyl length, root length, plant height, leaf length and width, and fresh and dry weights under optimal and stress conditions. There was Improved photosynthesis activity, chlorophyll content, survival rate, relative water content, endogenous catalase (CAT), and peroxidase (POD) concentration with a significantly lower electrolyte leakage percentage, malondialdehyde (MDA) content, and hydrogen peroxide (H2O2) concentration in overexpression lines compared to wild-type Arabidopsis under drought and salt stress conditions. Exposure to stress conditions resulted in relatively weaker roots and above-ground plant growth inhibition, enhanced endogenous levels of major antioxidant enzymes, which correlated well with lower lipid peroxidation, lower levels of reactive oxygen species, and reduced cell death in overexpression lines. The data of the current study demonstrated that TrIAA27 is involved in positively regulating plant growth and development and could be considered a potential target gene for further use, including the breeding of white clover for higher biomass with improved root architecture and tolerance to abiotic stress.

Gpx4 Regulates Invariant NKT Cell Homeostasis and Function by Preventing Lipid Peroxidation and Ferroptosis.

Invariant NKT (iNKT) cells are a group of innate-like T cells that plays important roles in immune homeostasis and activation. We found that iNKT cells, compared with CD4+ T cells, have significantly higher levels of lipid peroxidation in both mice and humans. Proteomic analysis also demonstrated that iNKT cells express higher levels of phospholipid hydroperoxidase glutathione peroxidase 4 (Gpx4), a major antioxidant enzyme that reduces lipid peroxidation and prevents ferroptosis. T cell-specific deletion of Gpx4 reduces iNKT cell population, most prominently the IFN-γ-producing NKT1 subset. RNA-sequencing analysis revealed that IFN-γ signaling, cell cycle regulation, and mitochondrial function are perturbed by Gpx4 deletion in iNKT cells. Consistently, we detected impaired cytokine production, elevated cell proliferation and cell death, and accumulation of lipid peroxides and mitochondrial reactive oxygen species in Gpx4 knockout iNKT cells. Ferroptosis inhibitors, iron chelators, vitamin E, and vitamin K2 can prevent ferroptosis induced by Gpx4 deficiency in iNKT cells and ameliorate the impaired function of iNKT cells due to Gpx4 inhibition. Last, vitamin E rescues iNKT cell population in Gpx4 knockout mice. Altogether, our findings reveal the critical role of Gpx4 in regulating iNKT cell homeostasis and function, through controlling lipid peroxidation and ferroptosis.

Mechanisms and Applications of Pseudomonas monteilii SX001: A Promising Agent for Improving Cucumber Tolerance to Salt Stress

To investigate the effects of Pseudomonas monteilii SX001 on various parameters of cucumber plants under salt stress, the salt-sensitive cucumber variety “Jinyou No. 4” was used as the test material, and coconut bran was used to simulate salt stress by applying NaCl solution. The results indicated that salt stress significantly reduced the morphological structure, relative growth rate, root morphology, and photosynthetic parameters of the cucumber plants. Leaf starch, soluble sugar, and sucrose contents significantly increased, whereas their levels in roots decreased. Cell membrane damage leads to the accumulation of reactive oxygen species and malondialdehyde, with notable increases in the activities of major antioxidant enzymes such as SOD, CAT, and POD. Nitrogen metabolism was disrupted, as evidenced by a significant decrease in nitrate nitrogen content and an increase in ammonium nitrogen content, as well as a significant reduction in the activity of NR enzymes involved in nitrogen metabolism. The enzyme activity in the cucumber rhizosphere soil decreased. However, Pseudomonas monteilii SX001 significantly enhanced the growth of cucumber seedlings under salt stress, improved photosynthetic efficiency, and facilitated sugar transformation and transport via glucose metabolism. Additionally, Pseudomonas monteilii SX001 reduced the reactive oxygen content and increased antioxidant enzyme activity. It also increased the activity of substrate enzymes and decreased the diversity of rhizosphere soil microorganisms but also increased the abundance of Asticcacaulis, Acinetobacter, Brevundimonas, Pseudomonas, and Enterobacter. These findings demonstrate that Pseudomonas monteilii SX001 is a promising bioinoculant for alleviating salt stress in cucumber production and improving soil health.

Dietary curcumin supplementation attenuates hepatic damage and function abnormality in a chronic corticosterone-induced stress model in broilers

Chronic stress refers to the activation of the hypothalamic-pituitary-adrenal (HPA) axis and elevated blood contents of ACTH and corticosterone (CORT), exhibiting significant adverse effects on health outcomes. Currently, natural polyphenol compounds are increasingly being explored as potential therapeutic agents and have been considered as a treatment option for a variety of stress-induced diseases. Curcumin (CUR) is the main substance in Curcuma longa (Zingiberacea) rhizome that has strong health-beneficial properties. The study aimed to assess the potential protective effects of CUR on hepatic oxidative stress damage and abnormal lipid deposition in a chronic CORT-induced stress (CCIS) model in broilers. One hundred and twenty experimental broilers were randomly divided into 1) control group (CON), 2) CUR group (200 mg/kg feed), 3) CORT group (4 mg/kg BW CORT) and 4) CORT+CUR group (200 mg/kg feed plus 4 mg/kg BW CORT). The liver histology, glycolipid metabolism and oxidative stress were determined. In addition, qPCR was performed to identify shifts in genes expression. Compared with CON group, broilers under CCIS showed a decreased body weight, body weight gain and average daily gain, while dietary CUR significantly reversed these adverse effects. Furthermore, the plasma contents of TCH, TG, HDL-C, LDL-C, TP, GLB and AST were all significantly increased in CCIS broilers, while dietary CUR obviously alleviated the increase of TCH, HDL-C, LDL-C and AST, and relieved the hepatic lipid deposition disorder and liver injury. Moreover, CCIS significantly increased the contents of MDA in both liver and plasma, and decreased the content of plasma SOD, while CUR obviously reversed these changes, showing reduced oxidative stress damage. Finally, the mRNA expressions of FAS, ACC, SCD and the protein level of PPAR-γ were significantly increased, meanwhile the mRNA expression of lipolytic genes ACOX1, ATGL and CPT as well as two major intracellular antioxidant enzymes SOD1 and GPX1 were obviously decreased, while CUR effectively reversed these effects. These results showed that dietary CUR effectively alleviated CCIS-induced body weight loss, hepatic oxidative damage and lipid deposition disorder, suggesting the possible therapeutic effectiveness of CUR against hepatic damage and function abnormality caused by CCIS.

Pepper catalase: a broad analysis of its modulation during fruit ripening and by nitric oxide.

Catalase is a major antioxidant enzyme located in plant peroxisomes that catalyzes the decomposition of H2O2. Based on our previous transcriptomic (RNA-Seq) and proteomic (iTRAQ) data at different stages of pepper (Capsicum annuum L.) fruit ripening and after exposure to nitric oxide (NO) enriched atmosphere, a broad analysis has allowed us to characterize the functioning of this enzyme. Three genes were identified, and their expression was differentially modulated during ripening and by NO gas treatment. A dissimilar behavior was observed in the protein expression of the encoded protein catalases (CaCat1-CaCat3). Total catalase activity was down-regulated by 50% in ripe (red) fruits concerning immature green fruits. This was corroborated by non-denaturing polyacrylamide gel electrophoresis, where only a single catalase isozyme was identified. In vitro analyses of the recombinant CaCat3 protein exposed to peroxynitrite (ONOO-) confirmed, by immunoblot assay, that catalase underwent a nitration process. Mass spectrometric analysis identified that Tyr348 and Tyr360 were nitrated by ONOO-, occurring near the active center of catalase. The data indicate the complex regulation at gene and protein levels of catalase during the ripening of pepper fruits, with activity significantly down-regulated in ripe fruits. Nitration seems to play a key role in this down-regulation, favoring an increase in H2O2 content during ripening. This pattern can be reversed by the exogenous NO application. While plant catalases are generally reported to be tetrameric, the analysis of the protein structure supports that pepper catalase has a favored quaternary homodimer nature. Taken together, data show that pepper catalase is down-regulated during fruit ripening, becoming a target of tyrosine nitration, which provokes its inhibition.

Glycated LDL generates reactive species that damage cell components, oxidize hemoglobin and alter surface morphology in human erythrocytes

Low-density lipoprotein (LDL) transports cholesterol to various tissues via the blood. Glycation of LDL occurs during hyperglycemic condition which is characterised by persistently high blood glucose level. Circulating erythrocytes can come in direct contact with glycated LDL (G-LDL). The objective of this study was to investigate the effect of G-LDL on human erythrocytes, specifically on hemoglobin, intracellular generation of reactive species and the antioxidant defence system. Isolated erythrocytes were incubated with G-LDL (3 and 6 mg/ml) and native LDL (6 mg/ml) at 37 °C for 24 h. Native LDL and G-LDL untreated erythrocytes were similarly incubated at 37 °C and served as control. G-LDL treatment increased hemolysis compared to control and native LDL-treated erythrocytes. Incubation of erythrocytes with G-LDL led to an increase in protein oxidation and lipid peroxidation while greatly decreasing the total sulfhydryl content. It also significantly enhanced hemoglobin oxidation, heme degradation, and the release of free iron moiety. Treatment with G-LDL led to an appreciable increase in the production of reactive oxygen and nitrogen species. The antioxidant power and activities of major antioxidant enzymes were drastically reduced, while critical membrane-bound enzymes were inhibited. The surface morphology of G-LDL-treated erythrocytes was altered leading to the formation of echinocytes. Importantly, treatment of erythrocytes with native LDL did not significantly affect the above-mentioned parameters and values were similar to the corresponding controls. Thus, G-LDL is cytotoxic to human erythrocytes and causes oxidative damage to cell components. This can reduce the oxygen-transporting ability of blood and also result in red cell senescence and anemia.

Zinc Oxide Nanoparticles Alleviate Salt Stress in Cotton (Gossypium hirsutum L.) by Adjusting Na+/K+ Ratio and Antioxidative Ability.

Soil salinization poses a threat to the sustainability of agricultural production and has become a global issue. Cotton is an important cash crop and plays an important role in economic development. Salt stress has been harming the yield and quality of many crops, including cotton, for many years. In recent years, soil salinization has been increasing. It is crucial to study the mechanism of cotton salt tolerance and explore diversified materials and methods to alleviate the salt stress of cotton for the development of the cotton industry. Nanoparticles (NPs) are an effective means to alleviate salt stress. In this study, zinc oxide NPs (ZnO NPs) were sprayed on cotton leaves with the aim of investigating the intrinsic mechanism of NPs to alleviate salt stress in cotton. The results show that the foliar spraying of ZnO NPs significantly alleviated the negative effects of salt stress on hydroponic cotton seedlings, including the improvement of above-ground and root dry and fresh weight, leaf area, seedling height, and stem diameter. In addition, ZnO NPs can significantly improve the salt-induced oxidative stress by reducing the levels of MDA, H2O2, and O2- and increasing the activities of major antioxidant enzymes, such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). Furthermore, RNA-seq showed that the foliar spraying of ZnO NPs could induce the expressions of CNGC, NHX2, AHA3, HAK17, and other genes, and reduce the expression of SKOR, combined with the CBL-CIPK pathway, which alleviated the toxic effect of excessive Na+ and reduced the loss of excessive K+ so that the Na+/K+ ratio was stabilized. In summary, our results indicate that the foliar application of ZnO NPs can alleviate high salt stress in cotton by adjusting the Na+/K+ ratio and regulating antioxidative ability. This provides a new strategy for alleviating the salt stress of cotton and other crops, which is conducive to the development of agriculture.

Gpx4 regulates iNKT cell homeostasis and function by preventing ferroptosis and lipid peroxidation

Abstract Invariant natural killer T (iNKT) cells are a group of innate-like T cells recognizing lipid Ags and plays important roles in immune responses. We found iNKT cells, compared to CD4T cells, have significantly higher level of lipid peroxidation, lower labile iron pool, and higher level of Gluthathione peroxidase 4 (GPX4), a major antioxidant enzyme protecting cells from ferroptosis. T cell-specific KO of Gpx4 reduced iNKT cells, especially NKT1 cells, the IFNg producing subset. RNAseq revealed Th1 pathway, cell cycle, and mitochondrial function are perturbed by Gpx4 deletion in iNKT cells. Indeed, we detected impaired cytokine production, elevated cell proliferation and cell death, accumulation of lipid peroxides and mitochondrial ROS in Gpx4 KO iNKT cells. Ferroptosis inhibitor, iron chelator, vitamins E, and mitochondrial antioxidant (MitoQ) prevented the ferroptotic cell death induced by Gpx4 inhibition in iNKT. Moreover, the function of the Gpx4 KO iNKT cells can be restored by antioxidants or iron chelator. Notably, vitamin E rescued iNKT cells at homeostasis in Gpx4KO mice. Furthermore, vitamin K2 prevented the cell death and restored the cytokine production in Gpx4-cKO iNKT cells in vitro, and it also recovered the percentage of iNKT1 in Gpx4 cKO mice when administrated in vivo, consistent with a protective role of vitamin K cycle during ferroptosis.

Antioxidants for Early Treatment of Type 2 Diabetes in Rodents and Humans: Lost in Translation?

Reactive oxygen species (ROS) are formed by virtually all tissues. In normal concentrations they facilitate many physiologic activities, but in excess they cause oxidative stress and tissue damage. Local antioxidant enzyme synthesis in cells is regulated by the cytoplasmic KEAP-1/ Nrf2 complex, which is stimulated by ROS, to release Nrf2 for entry into the nucleus where it upregulates antioxidant gene expression. Major antioxidant enzymes include glutathione peroxidase (GPx), catalase (CAT), superoxide dismutases (SOD), hemoxygenases (HO), and peroxiredoxins (Prdx). Notably, the pancreatic islet beta cell does not express GPx or CAT, which puts it at greater risk for ROS damage caused by postprandial hyperglycemia. Experimentally, overexpression of GPx in beta cell lines and isolated islets as well as in vivo studies using genetic models of type 2 diabetes, have demonstrated enhanced protection against hyperglycemia and oxidative stress. Oral treatment of diabetic rodents with Ebselen, a GPx mimetic that is approved for human clinical usereproduced these findings. Prdxs detoxify hydrogen peroxide and reduce lipid peroxides. This suggests that pharmacologic development of more potent, beta cell specific antioxidants could be valuable as a treatment for oxidative stress due to post-prandial hyperglycemia in early type 2 diabetes in humans.

Allantoin and Tissue Specific Redox Regulation in Mud Crab Scylla serrata under Varied Natural Water Physico-Chemical Parameters

Effects of varied sediment and physico-chemical properties of water on allantoin content in tissues of Scylla serrata and its role in antioxidant homeostasis were investigated. Tissues of crabs were sampled from different coastal natural habitats of S. serrata of India during summer, winter, and rainy seasons and were analyzed to detect the variation in allantoin content and lipid peroxidation (LPx) and oxidative stress (OS) neutralizing antioxidant factors. High allantoin content in hepatopancreas over muscle tissue was observed in all seasons and sampling sites. The correlation coefficient values between allantoin and environmental factors, i.e., temperature, pH, salinity, organic carbon, Mg, and Ca, strongly support the stress-induced allantoin variation level in tissues. The level of allantoin had a negative correlation with levels of ROS, which was probably due to the upregulation of the activity of major antioxidant enzymes and assisting enzymes such as glutathione peroxidase (GPx), glutathione reductase (GR), and biotransforming enzyme glutathione -s- transferases (GST). A significant seasonal variation in the level of allantoin was correlated with the activity of including superoxide dismutase, catalase, GPx, GR, and GST, which was clearly noticed as a function of abiotic factors. Additionally, the level of allantoin did not correlate with small antioxidant molecules, such as ascorbic acid and reduced glutathione. Discriminant function analysis revealed that the level of allantoin and CAT and GR activities were the major contributing factors for the clear discrimination of groups. Therefore, allantoin can be considered as a significant factor for the seasonal modulation of OS physiology in mud crab Scylla serrata.

Exploring the efficacy of the wild mushroom Astraeus hygrometricus extract on lipid profiles, insulin resistance, and oxidative stress in rats fed a high-fat diet

Edible wild mushrooms are considered to contain healthy bioactive ingredients that exert various pharmacological effects. We aimed to determine the antihyperlipidemic, antihyperglycemic, and antioxidant effects of the wild mushroom Astraeus hygrometricus (A. hygrometricus) extract in a rat model of dyslipidemia induced by a high-fat diet (HFD). Experimental rats received an HFD with or without A. hygrometricus extract (500 mg/kg body weight) or simvastatin (10 mg/kg body weight, a positive control) for 63 days. Oral administration of the extract decreased the blood glucose, glycated hemoglobin, triglyceride, and low-density lipoprotein cholesterol levels; counteracted insulin resistance; and increased the high-density lipoprotein cholesterol levels in HFD-fed rats. These changes were accompanied by a decrease in serum malondialdehyde and an increase in the activities of superoxide dismutase and glutathione peroxidase, two major antioxidant enzymes. Overall, A. hygrometricus extract supplementation alleviates hyperglycemia and hyperlipidemia in HFD-fed rats by decreasing insulin resistance and reducing oxidative stress.

Alleviating effect of whey protein supplementation on oxidative stress in hypothyroidism.

Hypothyroidism is one of the most prevalent thyroid pathologies, which causes oxidative stress by disrupting antioxidant mechanisms. In mammals, the thyroid glands regulate metabolism, development, and growth. Dysfunction of the thyroid gland can result in hypothyroidism, hyperthyroidism, thyroiditis, and thyroid cancer. Whey protein is a widely consumed protein supplement containing abundant sulphur-containing amino acids and bioactive peptides. Here, we analysed the effect of whey protein on oxidative stress in hypothyroidism. In vivo studies were conducted in two phases for 30 and 90 days, respectively. Hypothyroidism was induced in Wistar albino rats by administering 0.05% propylthiouracil (PTU) through drinking water. Five hypothyroid groups and the normal control group were maintained in the first 30 day phase of the study. Among these, one group served as the induced control group, three groups received whey protein at different concentrations (100, 300, and 500 mg per kg body weight), and the last group received L-thyroxine (2 μg per 100 g body weight) as a positive medication. The activities of antioxidant enzymes, such as superoxide dismutase, catalase, glutathione peroxidase, and glutathione-S-transferase, were analysed, and the levels of total antioxidants, glutathione, and malondialdehyde were determined. Ca2+ ATPase and Na+/K+ ATPase activities were detected by estimating the inorganic phosphate content. Histopathological analysis was carried out on the thyroid and liver tissues of all groups. Antioxidant activity was notably increased for higher doses of whey protein compared to that in the diseased control group (p < 0.05). From this initial study, the dose that achieved the desired therapeutic effect was 500 mg kg-1, which was considered for the next 90 day phase of the study. The 90 day phase of the study was conducted with five groups: normal, whey protein-supplemented, hypothyroid, whey protein-supplemented hypothyroid, and levothyroxine-supplemented hypothyroid. All the PTU-treated groups showed degenerative alterations in thyroid histology. Whey protein supplementation causes a considerable decrease in MDA levels with an increase in the major antioxidant enzyme and ATPase activities, with p < 0.05. As a nutritional supplement, whey protein, at a 500 mg kg-1 dose, effectively boosts antioxidant activity without causing any toxicological concerns in long-term use.

Toxicity of environmentally relevant concentration of PFAS chemicals in Lumbriculus variegatus (Oligochaeta, Lumbriculidae) – A multi-bioindicator study

PFAS, or per- and polyfluoroalkyl substances, are a family of man-made chemicals found in a variety of products from non-stick cookware and food wrappers to firefighting foams. PFAS are persistent and widely distributed in the environment, including aquatic environments. In this study we examined the impact of PFAS chemicals on the physiological and behavioral endpoints of Lumbriculus variegatus (i.e., blackworms). Lumbriculus variegatus is a species of freshwater annelid worm that plays key roles in shallow freshwater ecosystems. At an environmentally relevant concentration of 1 μg/L, 12-day aqueous exposure to long chain PFAS, including PFOA, PFOS and PFDA, each markedly slowed the pulse rate of the dorsal blood vessel in L. variegatus, indicating a suppressive effect on blood circulation. The mean pulse rate was reduced from 9.6 beats/minute to 6.2 and 7.0 beats/min in PFOA and PFOS, respectively (P < 0.0001). Further, PFOA, PFOS and PFDA reduced the escape responsiveness of L. variegatus to physical stimulation. The percentage of worms showing normal escape behavior was reduced from 99.0% in control to 90.6% in the PFOS exposed group (P < 0.01). In a chronic (4 week) growth study, exposure to overlying water and sediment spiked with PFOA, PFOS or PFDA reduced the total biomass and the number of worms, indicating a suppressive effect on worm population growth. For instance, PFOA and PFDA reduced the total dry biomass by 26.3% and 28.5%, respectively, compared to the control (P < 0.05). The impact of PFAS on blackworm physiology is accompanied by an increase in lipid peroxidation. The level of malondialdehyde (MDA), an indicator of lipid peroxidation, and catalase, a major antioxidant enzyme, were markedly increased in PFOA, PFOS and PFDA exposed groups. Interestingly, exposure to PFHxA, a short chain PFAS, had no detectable effect on any of the measured endpoints. Our results demonstrate that L. variegatus is highly sensitive to the toxic impact of long chain PFAS chemicals as measured by multiple endpoints including blood circulation, behavior, and population growth. Such toxicity may have a detrimental impact on L. variegatus and the freshwater ecosystems where it resides.

Every-other day (EOD) feeding regime decreases oxidative stress and inflammatory cascade in mouse liver: The immunohistochemical study

IntroductionPositive effects of calorie restrictions (CR) and EOD include decreased body weight, prolonged life span, but also changes in metabolism of the liver. In present paper our aim was to examine antioxidative enzymes: Catalase (CAT) and Manganese superoxidative dismutase (MnSOD, SOD2) and Glutathione peroxidase 4 (Gpx-4) in connection to caspase-3 and inflammatory mediators (IL-1β and TNF- α) in EOD liver tissue in comparison to control mice. MethodsAfter 9 months of EOD treatment male mouse liver tissue was harvested and prepared for analysis. Protein semi-quantitative estimation and cellular immunolocalization was performed for CAT, SOD2, Gpx-4, caspase-3, IL-1β and TNF- α in liver tissue of mice fed every-other day in comparison to control (AL fed) animals. ResultsAfter prolonged EOD feeding in mice we observed decreased level of SOD2 and Gpx-4, decreased caspase-3, IL-1β and TNF-α expression in liver tissue on protein level measured by semi-quantitative DAB staining intensity. ConclusionFor the first time we showed immunolocalization of major antioxidative enzymes (CAT, SOD2, Gpx-4) in liver tissue after DR. Decrease of two major antioxidant enzymes combined with decrease of apoptotic marker and inflammatory factors indicate decrease in oxidative stress as the result of fast in EOD feeding regime.

Curcumin Protects Pheochromocytoma Cells Against Hydrogen Peroxide-Induced Oxidative Stress

Objective: Oxidative stress represents a characteristic of neurodegenerative diseases, which may be alleviated by the functional food component—curcumin. However, the underlying mechanism remains unclear. The current study aimed to address how curcumin protects variant differentiated pheochromocytoma (PC12) cells against hydrogen peroxide (H2O2)-induced cell stress, using low- and high-differentiated PC12 cells, and validated in old-aged mice. Methods: The MTT assay was first carried out to test the cell viability upon H2O2 and/or curcumin treatment and cellular lipid peroxidation was assessed as cellular damages by quantifying the amount of cellular malondialdehyde. Cellular oxidative stress was determined by measuring the cellular and mitochondrial ROS levels, and total cellular antioxidant capacities were determined as the ABTS free radical scavenging ability (ABTS) and Fe3+ reduction ability of cells. The activities and expression of major antioxidant enzymes, including glutathione peroxidase (GPx), superoxidase dismutase (SOD) and catalase (CAT), were also tested. Furthermore, oxidative phosphorylation of mitochondria was assessed by measuring the ATP level and the ADP/ATP ratio. Finally, the antioxidant activity of curcumin was determined in 6-month-old mice by measuring cellular antioxidant capacity and antioxidant enzyme activities. Results: H2O2 caused oxidative damage and decreased cell viability, which was reversed by curcumin with different dosed effects in variant differentiated PC12 cells. Moreover, curcumin's protective effect was attributed to an enhanced antioxidant enzyme system. In consistent, curcumin recovered H2O2-deteriorated oxidative phosphorylation. Further studies verified that curcumin significantly improved the antioxidant capacity of old-aged mice, which may have elevated oxidative stress. Conclusion: Taken together, curcumin improved the antioxidant capacity of variant differentiated PC12 cells and old-aged mice, which was closely associated with the modulation of mitochondrial function and antioxidant enzyme system. This study may shed light on the molecular mechanism underlying the alleviation of neurodegenerative diseases by natural polyphenols.

Bacillus-Derived Manganese Superoxide Dismutase Relieves Ocular-Surface Inflammation and Damage by Reducing Oxidative Stress and Apoptosis in Dry Eye.

We hypothesized that antioxidative enzymes supplementation could be a treatment option for dry eye. We investigated the efficacy of oral administration of Bacillus-derived superoxide dismutase (Bd-SOD) in a murine experimental dry eye (EDE). In part I, mice were randomly assigned to normal control, EDE, and mice groups that were treated with oral Bd-SOD after induction of EDE (EDE + Bd-SOD group; four mice in each group). Expression of SOD2, a major antioxidant enzyme with manganese as a cofactor, was assessed by immunofluorescence staining. In part II, mice were divided into seven groups (six mice in each group): normal control, EDE, vehicle-treated, topical 0.05% cyclosporin A (CsA)-treated, and oral Bd-SOD-treated (2.5, 5.0, and 10.0mg/kg Bd-SOD) groups. Tear volume, tear-film break-up time (TBUT), and corneal fluorescein-staining scores (CFS) were measured at zero, five, and 10days after treatment. Tendays after treatment, 2',7'-dichlorodihydrofluorescein diacetate for reactive oxygen species (ROS), enzyme-linked immunosorbent for malondialdehyde, and TUNEL assays for corneal apoptosis, flow cytometry inflammatory T cells, and histological assessment were performed. Compared to the normal control group in part I, the EDE group showed significantly decreased SOD2 expression by immunofluorescence staining. However, the EDE + Bd-SOD group recovered similar to the normal control group. In part II, ROS, malondialdehyde, and corneal apoptosis were decreased in CsA and all Bd-SOD-treated groups. Corneal and conjunctival inflammatory T cells decreased, and conjunctival goblet cell density increased in CsA-treated and Bd-SOD-treated groups. Compared to the CsA-treated group, the 2.5mg/kg Bd-SOD-treated group showed increased TBUT and decreased inflammatory T cells, and the 5.0mg/kg Bd-SOD-treated group showed decreased CFS and increased conjunctival goblet cells. Oral Bd-SOD administration might increase autogenous SOD2 expression in ocular surface tissue in EDE and could be developed as a complementary treatment for DE in the future.

Hepatoprotective effects of ethnic cabbage dishes: a comparison study on kimchi and pao cai

Consuming ethnic vegetable dishes, that has been an integral part in the food culture of many countries, is suggested to bring health benefits to humans. Kimchi from Korea and pao cai from China are two distinct vegetable dishes made from Chinese cabbage (Brassica rapa) through different processes. While kimchi is a fermented food, pao cai is produced by pickling in brine or vinegar. The present study aimed to investigate and compare the hepatoprotective effects of kimchi and pao cai in vivo using animal model and in vitro using a cell line. Despite having similar nutritional profiles, kimchi and pao cai exhibited different chemical and microbiological properties. Compared to pao cai, the pH during fermentation of kimchi dropped more rapidly and the antioxidant activity of kimchi was also stronger. In addition, total microorganisms and lactic acid bacteria were consistently higher in kimchi than in pao cai. In vivo, the hepatoprotective properties of kimchi and pao cai were associated with the increase in expression and activity of major liver antioxidant enzymes, particularly glutathione reductase, glutathione peroxidase, glutathione S-transferase, catalase, and superoxide dismutase. In vitro, both kimchi and pao cai promoted the formation of glutathione. Upon exposure to chemically induced oxidative stress, kimchi protected liver cells by inhibiting glutathione depletion and limiting lipid peroxidation. In general, kimchi demonstrated stronger hepatoprotective properties compared to pao cai. Thus, the present study provides promising insights into the development of ethnic foods, particularly kimchi and pao cai, as functional foods beneficial for human health.

Trace Elements and Their Management in Dialysis Patients—Pathophysiology and Clinical Manifestations

Recently, as the number of elderly dialysis patients has been increasing, complications associated with low nutritional status such as infectious disease have had a strong influence on the prognosis of dialysis patients. Nutritional disorders are caused by the inadequate intake of the three major nutrients—proteins, fats, and carbohydrates—as well as vitamin and mineral deficiencies. Minerals are composed of various elements, including small-amount elements and trace elements, which are present in the human body in very small quantities lower than that of iron. In dialysis and predialysis patients, zinc, manganese, and selenium are the three major elements that are significantly depleted as compared to normal subjects; these deficiencies are sometimes symptomatic. Zinc deficiency is manifest as anemia, taste abnormality, and delayed wound healing, while selenium deficiency is associated with impaired cardiac function and immunocompromised condition. Zinc has multiple functions, since various enzymes, including DNA polymerase and RNA polymerase, need zinc as a cofactor, while selenium is a component of selenoproteins, including glutathione peroxidase and thioredoxin reductases, which are major antioxidative stress enzymes. These elements can only be supplemented exogenously and contribute to the sustainable QOL of dialysis patients. On the other hand, as regards other trace elements, including copper, chromium, manganese, lead, arsenic, etc., the association of their deficiency or intoxication with various involvements of dialysis patients were investigated, although all investigations were performed in cross-sectional studies or observational studies. Therefore, the supplementation of these elements is inconclusive, given the scarcity of other intervention studies. More conclusive studies are endorsed for the establishment of proper supplementation strategies.