Membrane Lipid Peroxidation Levels Research Articles

Low-molecular-weight organic acid-mediated tolerance and Pb accumulation in centipedegrass under Pb stress

Lead (Pb) is one of the most harmful, toxic pollutants to the ecological environment and humans. Centipedegrass, a fast-growing warm-season turfgrass, is excellent for Pb pollution remediation. Exogenous low-molecular-weight organic acid (LMWOA) treatment is a promising approach for assisted phytoremediation. However, the effects of this treatment on the tolerance and Pb accumulation of centipedegrass are unclear. This study investigated these effects on the physiological growth response and Pb accumulation distribution characteristics of centipedegrass. Applications of 400 μM citric acid (CA), malic acid (MA) and tartaric acid (TA) significantly reduced membrane lipid peroxidation levels of leaves and improved biomass production of Pb-stressed plants. These treatments mainly increased peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) activities and enhanced free protein (Pro), ascorbic acid (AsA) and phytochelatins (PCs) contents, ultimately improving the Pb tolerance of centipedegrass. Their promoting effects decreased as follows: TA>CA>MA. All the treatments decreased root Pb concentrations and increased stem and leaf Pb concentrations, thus increasing total Pb accumulation and TF values. MA had the best and worst effects on Pb accumulation and Pb transportation, respectively. CA had the best and worst effects on Pb transportation and Pb accumulation, respectively. TA exhibited strong effects on both Pb accumulation and transport. Furthermore, all treatments changed the subcellular Pb distribution patterns and distribution models of the chemical forms of Pb in each tissue. The root Pb concentration was more highly correlated with the Pb subcellular fraction distribution pattern, while the stem and leaf Pb concentrations were more highly correlated with the distribution models of the chemical forms of Pb. Overall, TA improved plant Pb tolerance best and promoted both Pb absorption and transportation well and is considered the best candidate for Pb-contaminated soil remediation with centipedegrass. This study provides a new idea for Pb-contaminated soil remediation with centipedegrass combined with LMWOAs.

Arbuscular Mycorrhizal Fungi and Endophytic Fungi Activate Leaf Antioxidant Defense System of Lane Late Navel Orange.

Arbuscular mycorrhizal (AM) fungi and endophytic fungi collectively symbiose well with plants and, thus, stimulate plant growth; however, it is not clear whether field inoculation of the fungi enhances the resistance potential of plants, particularly in citrus. In the present study, we inoculated AM fungi (Acaulospora scrobiculata, Diversispora spurca, and D. versiformis) and endophytic fungi (Piriformospora indica) on an eight-year-old lane late navel orange (Citrus sinensis (L.) Osb) trees grafted on Poncirus trifoliata in a field, and we analyzed the response of the leaf antioxidant defense system. Approximately 2 years after inoculation, the root fungal colonization rate and soil hyphal length significantly increased. Fungal inoculation significantly increased the activity of leaf antioxidant enzymes, such as superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase, and the content of non-enzymatic antioxidants, such as reduced ascorbic acid and reduced glutathione. As a result, fungi-inoculated plants maintained lower concentrations of hydrogen peroxide and superoxide anion radicals and lower levels of membrane lipid peroxidation (according to malondialdehyde level) in leaves than uninoculated plants. Among them, inoculation of D. spurca and A. scrobiculata showed relatively higher effects in enhancing the antioxidant defense system than the other fungi. Furthermore, inoculation of D. spurca induced expressions of CsFe-SOD, CsMn-SOD, CsPOD, CsCAT1, and CsPRR7; inoculation of A. scrobiculata and D. versiformis induced expressions of CsCAT1; CsCAT1 and CsPOD were also induced by inoculation of P. indica. All four inoculations almost upregulated expressions of CsFAD6. AM fungi had superior effects than endophytic fungi (e.g., P. indica). According to our findings, inoculation with beneficial fungi, specifically mycorrhizal fungus D. spurca, activated the antioxidant defense system of field citrus trees, thus, having potentially superior resistance in inoculated plants.

Anti-inflammatory role demonstrated both in vitro and in vivo models using nonsteroidal tetranortriterpenoid, Nimbin (N1) and its analogs (N2 and N3) that alleviate the domestication of alternative medicine.

Human health may benefit from the study of natural compounds and phytoconstituents that can protect from inflammation. We investigated Nimbin (N1), a member of the ring C Seco-tetranortriterpenoids family, and its semi-natural analog deacetyl Nimbin namely N2 and N3 for their anti-inflammatory properties. As key findings, N1, N2, and N3 were able to improve wound healing by cell proliferation in a period of 24 h and were able to reduce the reactive oxygen species (ROS) production in Madin-Darby Canine Kidney cells which were screened using dichloro-dihydro fluorescein diacetate (DCF-DA) staining. When the zebrafish larvae were subjected to DCF-DA assay N1, N2, and N3 were able to substantially reduce the ROS levels in a dose-dependent manner. In zebrafish larvae, the cell death indicates the fluorescent intensity due to acridine orange staining that was found to be dramatically decreasing upon the treatment of N1, N2, and N3. The cell membrane lipid peroxidation levels were also reduced in a dose-dependent manner upon the treatment of Nimbin and its analogs indicating lesser blue fluorescent levels. Among the Nimbin and its analogs, N2 was subjected to have better activity. To confirm the activity of N1, N2, and N3, in silico characterization was performed using Density functional theory and molecular docking. As a result, N2 exhibited the lowest electronegative value and highest binding energy when docked with anti-inflammatory and antioxidant proteins CAT, COX, GP, IL-1, and MPO. Furthermore, the therapeutic potential of N2 must be explored at the molecular level as well as in clinical studies for the treatment of inflammation-associated diseases.

Multiple metals and agricultural use affects oxidative stress biomarkers in freshwater Aegla crabs

Metals and agrochemicals are among the main aquatic contaminants, being able to trigger oxidative stress in exposed organisms. The objective of this work was to evaluate the correlation between the level of oxidative stress biomarkers in Aegla crabs (Crustacea, Anomura) with (i) the set of metals present in the streams sediment and (ii) with land uses of three hydrographic basins. The study was carried out in streams (≤ 2nd order) of hydrographic basins in southern Brazil (Basins of Rio Suzana, Rio Ligeirinho-Leãozinho and Rio Dourado). In these streams were quantified the land uses and Cu, Cr, Cd, Fe, Mn and Zn concentrations in the sediment. The enzymes Catalase (CAT) and Glutathione Reductase (GR), as well as the level of membrane lipid peroxidation (TBARS), were analyzed in adult females. The PCA analysis showed that the distribution of metals was different between the basins. Cd, Cr and Fe were correlated positively with CAT and negatively with TBARS and GR. The Dourado basin had the lowest concentrations of these three metals and the highest levels of TBARS. However, in Dourado basin there is predominance of agriculture land use, and TBARS was positively correlated with agricultural land use. Besides in Dourado basin, GR activity was higher than in the others basins, indicating a compensatory response in relation to CAT inhibition. The basins of Suzana and Ligeirinho-Leãozinho rivers had lower TBARS values, which may be due to the induction of CAT in response to metals accumulated in sediment. In summary, this work indicates that in the basins with a higher concentration of toxic metals there is an adaptive response of CAT induction, which reduces TBARS in Aegla. On the other hand, in the basin with lower metallic contamination, TBARS occurrence was primarily influenced by agricultural land use.

Synergistically enhanced Salmonella Typhimurium reduction by sequential treatment of organic acids and atmospheric cold plasma and the mechanism study

Salmonella, a foodborne pathogen, has been frequently associated with recalls of fresh food products, including poultry meat products. Atmospheric cold plasma (ACP) is a novel non-thermal technology, which has potential to reduce pathogens in food products. This study demonstrates the synergistic interactions of food grade organic acids (i.e., lactic acid (LA) or gallic acid (GA)) and ACP to inactivate Salmonella enterica Typhimurium ATCC 13311 inoculated on polycarbonate membrane filter paper and poultry meat surface. Organic acids were used in the form of a spray to enhance dispersion on samples surface. The sequential treatment of organic acid followed by ACP synergistically reduced S. Typhimurium on poultry meat surface. Irrespective of the type of organic acid, an average reduction of more than 3.5 log CFU/cm2 in S. Typhimurium on filter paper was obtained, when a combination of 10 mM LA or GA with an ACP exposure of 30 s was tested. However, the individual treatments of LA, GA, and ACP resulted in only 0.4, 0.3, 1.2 log CFU/cm2 reduction in S. Typhimurium, respectively. On poultry meat surface, a higher level of organic acid concentration (i.e., 50 mM) in combination with 30 s ACP was required to achieve more than 2.5 log CFU/cm2 reduction in S. Typhimurium. Our investigation on inactivation mechanisms revealed that the sequential treatment of LA or GA with ACP resulted in a significantly higher level of membrane permeability and membrane lipid peroxidation in S. Typhimurium cells. Additionally, the combined treatment significantly reduced the cell metabolic activity and affected the intracellular reactive oxygen species level of S. Typhimurium. In summary, this study demonstrated the potential synergistic benefits of combining organic acids and ACP to achieve a higher level of bacterial inactivation.

Antioxidant defense of fish collagen peptides attenuates oxidative stress in gastric mucosa of experimentally ulcer-induced rats.

The aim of the present study was to investigate the ability of fish collagen peptides (FCP) from the skin of great hammerhead shark (Sphyrna mokarran) to avert the occurrence of gastric ulcer in experimental rats. FCP treatment prevented the formation of ulcerative lesions on gastric tissues with 86% of inhibition. The histopathology analysis of gastric tissue revealed that the FCP intake prevented the occurrence of hemorrhage and erosion in gastric tissue with formation of mild edema and necrosis, as well as normalized the pH and volume of gastric juice. It also downregulated the expression of pro-inflammatory marker interferon-ɤ (IFN-ɤ) and upregulated the anti-inflammatory marker interleukin-4 (IL-4) in gastric tissue. FCP is capable to modulate the oxidative stress by enhancing the activity of antioxidant defense enzymes superoxide dismutase (SOD) and catalase and by lowering the levels of membrane lipid peroxidation.

Comparative Physiological and Proteomic Analyses Reveal the Mechanisms of Brassinolide-Mediated Tolerance to Calcium Nitrate Stress in Tomato.

Secondary salinization caused by the overaccumulation of calcium nitrate [Ca(NO3)2] in soils due to excessive fertilization has become one of the major handicaps of protected vegetable production. Brassinolide, a bioactive plant steroid hormone, plays an important role in improving abiotic stress tolerance in plants. However, whether and how brassinolide (BR) can alleviate Ca(NO3)2 stress remains elusive. Here, we investigated the effects of exogenous BR on hydroponically grown tomato (Solanum lycopersicum L.) plants under Ca(NO3)2 stress through proteomics combined with physiological studies. Proteomics analysis revealed that Ca(NO3)2 stress affected the accumulation of proteins involved in photosynthesis, stress responses, and antioxidant defense, however, exogenous BR increased the accumulation of proteins involved in chlorophyll metabolism and altered the osmotic stress responses in tomatoes under Ca(NO3)2 stress. Further physiological studies supported the results of proteomics and showed that the exogenous BR-induced alleviation of Ca(NO3)2 stress was associated with the improvement of photosynthetic efficiency, levels of soluble sugars and proteins, chlorophyll contents, and antioxidant enzyme activities, leading to the reduction in the levels of reactive oxygen species and membrane lipid peroxidation, and promotion of the recovery of photosynthetic performance, energy metabolism, and plant growth under Ca(NO3)2 stress. These results show the importance of applying BR in protected agriculture as a means for the effective management of secondary salinization.

Pterocarpus santalinus L. extract mitigates gamma radiation-inflicted derangements in BALB/c mice by Nrf2 upregulation

Plant-based natural extracts contain several nutrients and bioactive compounds, such as phenolics and flavonoids, that possess various health-promoting activities. This study investigated the effects of polyphenols from Pterocarpus santalinus hydroalcoholic extract (PSHE) against gamma radiation-induced derangements via the upregulation of Nrf2. Ultra High Performance Liquid Chromatography Coupled to High Resolution Mass Spectrometry (UHPLC-HRMS/MS) analysis was performed to identify the possible radioprotectors. In vivo and in vitro studies, namely Real-Time-PCR (RT-PCR) analysis, Reactive Oxygen Species (ROS) scavenging activity, lipid peroxidation and GSH levels, DNA damage and cell death studies, anti-inflammatory (Sandwich ELISA), immunomodulatory studies (antibody staining), and model free radical scavenging assays, were performed. Vanillic acid, protocatechuic acid, para-hydroxybenzoic acid, chlorogenic acid, TNF-α inhibitor (Eudesmin), isoflavone (Daidzein 7-o-glucoside), astragalin (Kaempferol 3-o-glycoside), and other polyphenols were identified in PSHE using UHPLC-HRMS/MS analysis. Prophylactic administration of PSHE (−1 h) rendered more than 33% survival in mice exposed to 8 Gy whole-body-irradiation with increased mice survival and recovery of bone marrow and spleen cellularity. Real-time RT-PCR analysis showed that PSHE treatment (50 µg/mL) upregulated Nrf2, HO-1, and GPX-1 in mice splenocytes. At 50 µg/mL, PSHE reduced ROSscavenging activity, mitochondrial and spleen membrane lipid peroxidation levels, DNA damage, and cell death, and increased GSH levels. At 10 µg/mL, PSHE treatment diminished the content of IL-6 and TNF-α. At 50 µg/mL, PSHE suppressed lymphocyte proliferation. These findings indicate that polyphenols of PSHE possess marked antioxidant, anti-inflammatory, and immunomodulatory capacities, which play important roles in the prevention of radiation damage.

Exposure-based ecotoxicity assessment of Co3O4 nanoparticles in marine microalgae.

The exposure-effect study was conducted to evaluate the effect of Co3O4 nanoparticles on Tetraselmis suecica. The growth suppressing effect has been observed during the interaction between nanoparticles and microalgae as indicated by 72 h EC50 (effective concentration of a chemical at which 50% of its effect is observed) value (45.13±3.95 mg/L) of Co3O4 nanoparticles for Tetraselmis suecica. Decline in chlorophyll a content also indicated the compromised photosynthetic ability and physiological state of microalgae. Further biochemical investigation such as increase in extracellular LDH (lactate dehydrogenase) level, ROS (reactive oxygen species), and levels of membrane lipid peroxidation in treated samples signifies the compromised cellular health and membrane disintegration caused by nanoparticles. Parallel to this, the cell entrapment, membrane damage, and attachment of nanoparticles on cell surface were also visualized by SEM-EDX (scanning electron microscope-energy dispersive X-ray) microscopy. The overall results of this study clearly indicated that Co3O4 nanoparticles might have toxic effects on growth of marine microalgae and other aquatic life forms as well. Hence, release of Co3O4 nanoparticles in aquatic ecosystem and resulting ecotoxic effect should be broadly addressed.

Melatonin alleviates imidacloprid phytotoxicity to cucumber (Cucumis sativus L.) through modulating redox homeostasis in plants and promoting its metabolism by enhancing glutathione dependent detoxification

Melatonin (Mel), a powerful antioxidant that has the ability to regulate physiological and biochemical processes in plants under abiotic stresses. However, its roles in pesticide detoxification is poorly understood. Herein, selecting leaf spraying insecticide imidacloprid (IMD) as the model, we demonstrated the detoxification mechanism underlying root pretreatment of Mel on IMD in cucumber. IMD treatment affected the primary light conversion efficiency of photosystem II (Fv/Fm), reduced the quantum yield, and increased hydrogen peroxide and superoxide anions contents as well as the levels of membrane lipid peroxidation, indicating that excessive IMD treatment induces oxidative stress. Nonetheless, by increasing the appropriate levels of exogenous Mel, the photosynthesis of cucumber under IMD treatment reached the control levels, effectively removing reactive oxygen species. Furthermore, the content and ratio of ascorbate (AsA) and glutathione (GSH) were decreased under IMD treatment; Mel treatment enhanced the AsA/DHA and GSH/GSSG ratios, as well as the activities of MDHAR, DHAR and GR, suggesting that Mel could alleviate oxidative stress of cucumber treated with IMD by regulating the ascorbic acid-glutathione cycle. Importantly, IMD degradation rate and glutathione S-transferase (GST) activity increased after Mel treatment. The levels of transcripts encoding antioxidant enzymes GPX and GST (GST1,2 and 3) were also increased, indicating that Mel accelerated IMD degradation. These results suggest that Mel plays an important role in the detoxification of IMD by promoting GST activity and transcription and the AsA-GSH cycle, thus providing an approach for plants to reduce IMD residue through the plant's own detoxification mechanism.

Cadmium stress alleviation potential of Bruguiera cylindrica (L.) Blume enhances in combination with NaCl

A hydroponic experiment in NaCl tolerant mangrove, Bruguiera cylindrica plantlets was done to investigate the interactive effects of CdCl2+NaCl as well as the individual effects of CdCl2. CdCl2 alone results in enhanced level of cell membrane lipid peroxidation, damaging normal structure, and function of the membrane and there by leading to reduction of membrane stability index and thus severely promoting the electrolyte leakage than the combined treatment of CdCl2+NaCl. Antioxidants greatly contribute to cope with the stress by scavenging ROS and were more prominent in individual stress than combined stress. B. cylindrica can be categorized as a highly tolerant mangrove species with a Tolerance Index (TI) of above 60% toward CdCl2+NaCl (TI is 70 and 75% in leaf and root). But TI was only 63 and 67% in leaf and root, respectively, on exposure to CdCl2 alone indicating that this plant is less tolerant to Cd alone. The existence of B. cylindrica depends on the heavy metals being introduced into the mangrove ecosystem and imparts a combination stress along with NaCl. In this regard, B. cylindrica survives up to 0.20 mM CdCl2 along with NaCl. Thus, the high NaCl tolerance mechanisms in this mangrove species could be equally efficient in imparting tolerance toward high concentration of Cd along with NaCl and exhibits phytostabilization in polluted coastal wetlands.

Co-overexpression of AtDREB1A and BcZAT12 increases drought tolerance and fruit production in double transgenic tomato (Solanum lycopersicum) plants

Drought is the major problem in agricultural production due to loss of moisture content in soil as well as climate variations. Our main aim is to enhance drought tolerance and yield potential in the present study pyramided Arabidopsis thaliana Dehydration Responsive Element Binding1A (AtDREB1A) and Brasica caranata Zinc finger proteins (BcZAT12) transcription factor genes driven by ectopic promoter rd29 A of Arabidopsis thaliana and Brassica carinata lea1, respectively. Co-overexpression of both the genes provides tolerance to multiple abiotic stresses but the AtDREB1A overexpression has been reported to cause retarded growth and dwarf phenotype; however BcZAT12 overexpressing transgenic plants does not show retarded growth and dwarf phenotype. Co-overexpressing of AtDREB1A and BcZAT12 in five (DZ1-DZ5) double transgenic (DT) tomato lines has been observed under 0, 07, 14 and 21 Days of Water Deficit (DWD). The DT plants showed enhanced drought tolerance and yield potential than single transgenic (ST) and non transgenic (NT) plants. Furthermore, AtDREB1A and BcZAT12 co-overexpressed plants showed reduced level of electrolyte leakage (EL), hydrogen peroxide and membrane lipid peroxidation and elevated level of relative water content (RWC), proline, chlorophyll color index (CCI) and photosynthetic efficiency as compared to ST and NT. The plant growth and yield attributes were improved by the co-overexpression of AtDREB1A and BcZAT12 in DT plants. The transcript analysis showed the increased level of DREB1A, ZAT12 and P5CS genes expression which were higher in DT tomato plants, and indicate that both the genes induce together in the DT plants. The present study which is first report of co-overexpressing AtDREB1A and BcZAT12 in tomato will provide a base for genetic engineering in plants through the multigenic transgenic approach to cope against various biotic and abiotic stresses.

Exogenous melatonin improves salt stress adaptation of cotton seedlings by regulating active oxygen metabolism.

Melatonin is a small-molecule indole hormone that plays an important role in participating in biotic and abiotic stress resistance. Melatonin has been confirmed to promote the normal development of plants under adversity stress by mediating physiological regulation mechanisms. However, the mechanisms by which exogenous melatonin mediates salt tolerance via regulation of antioxidant activity and osmosis in cotton seedlings remain largely unknown. In this study, the regulatory effects of melatonin on reactive oxygen species (ROS), the antioxidant system, and osmotic modulators of cotton seedlings were determined under 0–500 µM melatonin treatments with salt stress induced by 150 mM NaCl treatment. Cotton seedlings under salt stress exhibited an inhibition of growth, excessive hydrogen peroxide (H2O2), superoxide anion (O2−), and malondialdehyde (MDA) accumulations in leaves, increased activity levels of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX), and elevated ascorbic acid (AsA) and glutathione (GSH) content in leaves. However, the content of osmotic regulators (i.e., soluble sugars and proteins) in leaves was reduced under salt stress. This indicates high levels of ROS were produced, and the cell membrane was damaged. Additionally, osmotic regulatory substance content was reduced, resulting in osmotic stress, which seriously affected cotton seedling growth under salt stress. However, exogenous melatonin at different concentrations reduced the contents of H2O2, O2−, and MDA in cotton leaves, increased the activity of antioxidant enzymes and the content of reductive substances (i.e., AsA and GSH), and promoted the accumulation of osmotic regulatory substances in leaves under salt stress. These results suggest that melatonin can inhibit ROS production in cotton seedlings, improve the activity of the antioxidant enzyme system, raise the content of osmotic regulation substances, reduce the level of membrane lipid peroxidation, and protect the integrity of the lipid membrane under salt stress, which reduces damage caused by salt stress to seedlings and effectively enhances inhibition of salt stress on cotton seedling growth. These results indicate that 200 µM melatonin treatment has the best effect on the growth and salt tolerance of cotton seedlings.

Phenotypical and functional abnormalities of circulating neutrophils in patients with β-thalassemia.

β-Thalassemia is an inherited single gene disorder related to reduced synthesis of the β-globin chain of hemoglobin. Patients with β-thalassemia present variable clinical severity ranging from asymptomatic trait to severe transfusion-dependent anemia and multiple organs complications. Moreover, multiple immune abnormalities are a major concern in β-thalassemia patients. Aberrant neutrophil effector function plays a pivotal role in infection susceptibility in these patients. In severe and persistent inflammation, immature neutrophils are released from the bone marrow and are functionally different compared with mature ones. Despite some abnormalities reported for thalassemia patient's immune system, few data exist on the characterization of human neutrophils in β-thalassemia. The aim of this study was to investigate the phenotype and function of circulating neutrophil subsets in patients with β-thalassemia major and with β-thalassemia intermedia divided in transfusion-dependent and non-transfusion-dependent. By the use of immunochemical and cytofluorimetric analyses, we observed that patients' CD16+ neutrophils exhibit abnormalities in their phenotype and functions and the abnormalities vary according to the clinical form of the disease and to the neutrophil subset (CD16bright and CD16dim). Abnormalities include altered surface expression of the innate immune receptor CD45, Toll-like receptor 4, and CD32, reduced ability to produce an oxidative burst, and elevated levels of membrane lipid peroxidation, especially in patients with a more severe form of the disease. Overall, our results indicating the occurrence of an immuno-senescent phenotype on circulating neutrophils from thalassemia patients suggest the usefulness of neutrophil feature assessment as a tool for better clinical management of β-thalassemia.

Transcriptomic analysis reveals hub genes and subnetworks related to ROS metabolism in Hylocereus undatus through novel superoxide scavenger trypsin treatment during storage

BackgroundIt was demonstrated in our previous research that trypsin scavenges superoxide anions. In this study, the mechanisms of storage quality improvement by trypsin were evaluated in H. undatus.ResultsTrypsin significantly delayed the weight loss and decreased the levels of ROS and membrane lipid peroxidation. Transcriptome profiles of H. undatus treated with trypsin revealed the pathways and regulatory mechanisms of ROS genes that were up- or downregulated following trypsin treatment by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) enrichment analyses. The current results showed that through the regulation of the expression of hub redox enzymes, especially thioredoxin-related proteins, trypsin can maintain low levels of endogenous active oxygen species, reduce malondialdehyde content and delay fruit aging. In addition, the results of protein-protein interaction networks suggested that the downregulated NAD(P) H and lignin pathways might be the key regulatory mechanisms governed by trypsin.ConclusionsTrypsin significantly prolonged the storage life of H. undatus through regulatory on the endogenous ROS metabolism. As a new biopreservative, trypsin is highly efficient, safe and economical. Therefore, trypsin possesses technical feasibility for the quality control of fruit storage.Graphical abstract

Quercetin supplementation to the thawing and incubation media of boar sperm improves post-thaw sperm characteristics and the in vitro production of pig embryos

Elevated levels of reactive oxygen species can cause oxidative stress, which could lead to membrane damage, decreased fertility, and spermatozoan morphological deformities. Antioxidants can be supplemented to reduce the impacts of oxidative stress. The objective of this study was to determine the effects of supplementing quercetin (0.25, 0.50, 0.75 mM) during the thawing and incubation of frozen-thawed boar semen on spermatozoan characteristics, IVF kinetics (n = 400) and subsequent embryonic development (n = 1340). Spermatozoa were evaluated for motility, viability, and membrane lipid peroxidation levels at 0, 2, 4, 6, 8, and 10 h after thawing. Embryos were evaluated for IVF kinetics 12 h after IVF (penetration, polyspermy, male pronucleus formation, IVF efficiency) and cleavage and blastocyst formation at 48 h and 144 h after IVF, respectively. Spermatozoa supplemented with 0.25 mM quercetin had significantly higher (P < 0.05) motility (51.67±8.50 %) and percent of viable cells (61.21 ± 2.44 %) compared to all other treatments at 10 h after thawing, in addition to having significantly (P < 0.05) lower levels of hydroperoxide (3.38 ± 0.88 μM/107cells). There were no differences in penetration rates and male pronucleus formation between treatment groups. Supplementation of quercetin significantly decreased (P < 0.05) polyspermy and significantly increased (P < 0.05) the percentage of embryos reaching blastocyst stage of development by 144 h after IVF compared to no supplementation. Results indicated that supplementing frozen-thawed boar semen with 0.25 mM quercetin improves sperm characteristics up to 10 h after thawing and decreases polyspermy while improving early embryonic development in pigs.

Trifluoperazine an Antipsychotic Drug and Inhibitor of Mitochondrial Permeability Transition Protects Cytarabine and Ifosfamide-Induced Neurotoxicity.

The link between Ca2+ dysregulation, mitochondria damages, oxidative stress and cellular derangement is particularly evident in neurotoxicity induced by chemotherapeutic agents. In the current study, we investigated effects of trifluoperazine (TFP) as an inhibitor of calmodulin against the cytotoxicity induced by cytarabine (Ara-C) and Ifosfamide (IFOS) on isolated rat neurons and also the mechanisms involved in this toxicity. Isolated rat neurons were pretreated with TFP (100 µM) for 5 min at 37°C, then Ara-C (226 µM) and IFOS (290 µM) were added in separate experiments. After 3 h, the cytotoxicity, reactive oxygen species (ROS), lysosomal membrane destabilization, mitochondrial membrane potential (MMP), lipid peroxidation (LP), glutathione (GSH) and glutathione disulfide (GSSG) levels were measured. Ara-C and IFOS treatments caused a significant decrease in cellular viability, which was accompanied by ROS generation, GSSG/GSH ratio, lipid peroxidation and lysosomal and mitochondrial damages. On the other hand, TFP (100 µM) pre-treatment attenuated Ara-C and IFOS -induced decrease in cell viability. In addition, TFP (100 µM) pre-treatment significantly protected against Ara-C and IFOS -induced increase in ROS generation, lysosomal and mitochondrial damages, lipid peroxidation levels and decrease in GSH/GSSG ratio. Our data provided insights into the mechanism of protection by TFP against Ara-C and IFOS neurotoxicity, which is related, to neuronal ROS formation and mitochondrial damages.

Reactive oxygen species induce cyanide-resistant respiration in potato infected by Erwinia carotovora subsp. Carotovora

Studies have shown that pathogenic bacteria infections induce the overproduction of reactive oxygen species (ROS) in plants. Cyanide-resistant respiration, an energy-dissipating pathway in plants, has also been induced by a pathogenic bacteria infection. However, it is unknown whether the induction of cyanide-resistant respiration under the pathogenic bacteria infection was caused by ROS. In this study, two pathogenic Erwinia strains were used to infect potato tuber, and membrane lipid peroxidation levels and the cyanide-resistant respiration capacity were determined. In addition, StAOX expression and regulation by ROS in potato tuber were analyzed. Moreover, the role of the Ca2+ pathway in regulating cyanide-resistant respiration was determined. The results showed that ROS induced cyanide-resistant respiration in potato tuber infected by Erwinia. Cyanide-resistant respiration inhibited the production of H2O2. Intracellular Ca2+ regulated the expression of calcium-dependent protein kinase (StCDPK1, StCDPK4, and StCDPK5) in potato, which indirectly controlled intracellular ROS levels. These results indicate that Ca2+ metabolism is involved in ROS-induced cyanide-resistant respiration.

38 Ram sperm longevity after cryopreservation in extender containing L-carnitine

The cryopreservation process causes oxidative stress to the sperm cell, and the addition of antioxidants to the extender for semen freezing helps sperm protection. This study assessed the effect of L-carnitine (LC) concentrations (0, 5, or 10mM LC) on two ram semen extenders (Tris-egg yolk or the commercial optiXcell IMV medium (IMV Technologies)) for semen cryopreservation. Four Santa Inês rams were used during the breeding season. After semen collection, macroscopic and microscopic evaluations were performed, and a pool of semen was formed. The semen was diluted, and the final concentration was 100×106 per 0.25-mL straw. Cryopreservation was performed with a cooling rate of 0.25°C min−1 until 5°C, and the freezing rate used was 20°C min−1 from 5 to −120°C. After the freezing-thawing process and throughout incubation (38°C in 5% CO2) in Fert-Tyrode's albumin lactate pyruvate medium, every 1h for up to 3h, several parameters were evaluated: sperm kinetics, hypo-osmotic test, plasma membrane integrity, capacitation status, and lipid peroxidation level. We did not find any protective effect of LC on plasma membrane integrity, hypo-osmotic test, and capacitation status. The sperm kinetics values throughout incubation showed that Tris extender promoted better indices of staight-line velocity, linearity, wobble, and straightness than IMV extender along incubation, regardless of the presence of LC. There were no benefits of the LC addition throughout the incubation, and 10mM was deleterious to few parameters (amplitude of lateral head displacement, linearity, and wobble) compared with the control (0mM) in the Tris extender group. The plasma membrane integrity analysis revealed no differences (P&amp;gt;0.05) among the groups. The average number of intact cells (hypo-osmotic) was higher in Tris extender groups supplemented with 10mM LC at 1h and 5mM LC at 2h compared to the respective extender IMV groups. Regarding capacitation status, the Tris 5mM LC group had more acrosome-reacted cells when compared with the IMV 5mM LC group at 2h. At 3h, the percentage of acrosome-reacted cells was higher in the Tris 0-mM group when compared with the IMV 0-mM group. Regardless the presence of LC, IMV had higher (P&amp;lt;0.05) lipoperoxidation than the Tris treatments. In conclusion, LC supplementation in semen extender had no beneficial effect on freezing-thawing ram sperm and throughout incubation for up to 3h, with no difference in each time point evaluated. Under the conditions of this study, the use of Tris extender was superior to IMV extender for ram sperm. Financial support for this work came from the Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (Young Scientist Program of Our State; E-26/203.168/2017).

Hepcidin Peptide Inhibitor as Cardioprotection by Targeting Oxidative Stress and Inflammation in Type 1 Diabetic

Hepcidin peptide is the dominant regulator of systemic iron metabolism. Studies suggest a dual role of hepcidin in neuronal iron load and inflammation. This is vital since iron load and inflammation are pathophysiological processes, which are frequently associated with diabetic cardiomyopathy. Furthermore, manipulation of hepcidin activity has recently been used to recover heart damage due to inflammation in type 1 diabetic animal models. In order to induce type 1 diabetic model, streptozotocin (STZ) was used. Animals were divided into groups of control (C), diabetic (D), diabetic + iron (ID), and diabetic + dalteparin (DD). Then, 100 mg/kg of dalteparin (anti-hepcidin) was administered intraperitoneally, and 12 mg/kg of iron administration P.O in rats once a day after diabetes for 8 weeks. At the end of the experiment, animals were perfused and their heart tissue was prepared to measure serum iron level, ferritin, inflammatory cytokines such as IL-6, serum C-reactive protein (CRP), oxidative stress markers such as membrane lipid peroxidation (MDA), and hepcidin peptide gene expression. After inhibiting hepcidin by dalteparin treatment, serum levels of IL-6, CRP, glucose levels, iron and tissue levels of MDA and ferritin were remarkably reduced (p < 0.05). Likewise, inhibiting hepcidin peptide improved cardiac complications 8 weeks after induced type 1 diabetic (p < 0.05). Manipulation of hepcidin peptide by dalteparin could ameliorate diabetic cardiomyopathy (DM) in streptozotocin-diabetic rats through appropriate modulation and mitigation of oxidative stress and inflammation and this may expand the existing library of therapeutics to lower the complications of diabetes.