Copper-zinc Superoxide Dismutase Research Articles

Dietary zinc supplementation in breeding pigeons improves the carcass traits of squabs through regulating antioxidant capacity and myogenic regulatory factor expression

The purpose of this experiment was to explore the effects of zinc supplementation in breeding pigeons diet on carcass traits, meat quality, antioxidant capacity and mRNA expressions of myogenic regulatory factors of squabs. A total of 120 healthy White King pigeons were randomly assigned to 5 treatments, each involving 8 replicates. The experiment lasted for 46 d (18-d incubation period of eggs and 28-d growth period of squabs). The 5 groups were 0, 30, 60, 90, and 120 mg/kg zinc addition. Results showed that the 28-d body weight, breast muscle yield, zinc content in crop milk and myogenic factor 6 (MyF6) abundance of breast muscle were linearly increased (P < 0.050), but the abdominal fat yield linearly decreased (P=0.040) with increasing dietary zinc supplementation. Both the linear (P < 0.050) and quadratic responses (P < 0.001) were observed in copper zinc superoxide dismutase (Cu-Zn SOD), total antioxidant capacity (T-AOC) and malondialdehyde (MDA) contents in liver and breast muscle. The 28-d body weight was increased by 90 mg/kg zinc supplementation (P < 0.05), and there is no significant difference between 90 and 120 mg/kg zinc addition. The breast muscle yield, Cu-Zn SOD and T-AOC contents in breast muscle and liver, zinc contents in crop milk and breast muscle, MyF6 mRNA expression in breast muscle were higher (P < 0.05) in the group supplemented with 120 mg/kg zinc than the control. The abdominal fat yield was numerically lowest, and MDA contents in breast muscle and liver were significantly lowest in the group fed 120 mg/kg zinc (P < 0.05). However, the meat quality traits were not affected (P > 0.05) by zinc supplementation, except for shear force. It should be stated dietary zinc supplementation at the level of 120 mg/kg for breeding pigeons increased body weight and breast muscle yield of squabs, which may be associated with the up-regulating MyF6 mRNA expression and antioxidant capacity in liver and breast muscle.

In vitro anticancer and antimicrobial activities of copper-zinc superoxide dismutase purified from Cellana rota snail

In vitro anticancer and antimicrobial activities of copper-zinc superoxide dismutase purified from Cellana rota snail

Exercise for myocardial ischemia-reperfusion injury: A systematic review and meta-analysis based on preclinical studies.

The main pathological manifestation of coronary artery disease is myocardial injury caused by ischemia-reperfusion (IR) injury. Regular exercise reduces the risk of death during myocardial IR injury. The aim of this study was to describe the effects of various types of exercise on myocardial IR injury. Four electronic databases PubMed, Web of Science, Embase, and Cochrane Library were comprehensively searched from inception until February 2022, to identify studies relevant to the current review, using the method of combining subject and free words. Finally, 16 articles were included in the meta-analysis. Results showed that exercise training decreases the Myocardial infarct size compared to the control group (SMD=-2.6, 95% CI [-3.53 to -1.67], P<0.01); increasing the coronary blood flow (MD=2.93, 95% CI [2.41 to 3.44], P<0.01), left ventricular developed pressure (SMD=2.28, 95% CI [0.12 to 4.43], P<0.05), cardiac output (SMD=1.22, 95% CI [0.61 to 1.83], P<0.01) compared to the control group. According to the descriptive analysis results also showed that exercise training increases the left ventricular ejection fraction, superoxide dismutase, manganese superoxide dismutase, glutathione peroxidase, copper-zinc superoxide dismutase, glutathione peroxidase, and decrease the creatine kinase, creatine kinase-MB, lactate dehydrogenase, Malondialdehyde, cardiac troponins T. Exercise can improve myocardial function after myocardial IR injury; however, further research is needed in combination with specific issues such as exercise mode, intensity, duration, and model issues.

Lack of Sod1 induces disruption of innervation accompanied by Schwann cell proliferation in skeletal muscle

The neuromuscular junction (NMJ) is an excitatory synapse that constitutes the primary site of communication between the nervous system and skeletal muscle and therefore any degenerative changes at the NMJ have the potential to impair muscle function. The primary cellular components of the NMJ are the motor neuron, the muscle fiber and terminal Schwann cells (tSC) that surround the NMJ. The importance of redox homeostasis for the maintenance of NMJ integrity is supported by work from our group showing degenerative changes at NMJs in mice lacking copper zinc superoxide dismutase (CuZnSOD; Sod1 -/- ) as early as 4 months of age. Prior work from others suggests that tSCs contribute trophic support for the NMJ and facilitate motor unit remodeling, but changes in tSC structure and function under conditions of elevated oxidative stress have not been thoroughly explored. Using in vitro assays, we previously showed that primary Schwann cells treated with a sublethal dose of the reactive oxygen species inducing agent Paraquat (PQ) resulted in increased Schwann cell number, ki67+ staining, and gene expression of trophic factors and the critical NMJ organizing protein Agrin. Furthermore, differentiated C2C12 myotubes treated with conditioned media from PQ treated Schwann cell cultures showed increased number of acetylcholine receptor (AChR) plaques. The goal of the current study was to characterize NMJs in young Sod1 -/- mice (2-months) to determine the early effects of elevated oxidative stress on NMJ structure in vivo with a specific focus on tSCs. We hypothesized that loss of Sod1 would lead to aberrant tSC and NMJ structure associated with decreased muscle function. We assessed maximum isometric force, NMJ morphology, and number of Schwann cells in gastrocnemius muscles of WT (n = 3) and Sod1 -/- (n = 3) mice. In Sod1 -/- mice, muscle force was reduced by 26% ( p = 2e-4) with nerve stimulation compared to direct muscle stimulation, and overlap between motor nerve terminals and AChRs was reduced by nearly 60% compared to WT controls. Post-synaptic AChR area was increased by 37% in Sod1 -/- mice, and tSC area and numbers per NMJ were increased by 60% and 155%, respectively in Sod1 -/- mice. Finally, Schwann cells proximal to NMJs showed increased Ki67+ labeling in Sod1 -/- mice compared to WT mice. This analysis demonstrates that early changes in both pre- and post-synaptic NMJ components and reduced neurotransmission due to loss of Sod1 are associated with marked increases in tSC proliferation. Our data implicate a protective role of muscle-resident Schwann cells in preserving NMJ integrity in response to alterations in redox homeostasis that may be mediated in part through activation and proliferation of these cells. These findings indicate that further investigation of the dynamics between Schwann cells and NMJ function is important to increase understanding of neuromuscular degenerativeconditions that involve altered redox homeostasis such as sarcopenia. Supported by the University of Michigan Medical School Office of Research, the American Physiological Society, and NIH AR069620. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Mannan oligosaccharides alleviate oxidative injury in the head kidney and spleen in grass carp (Ctenopharyngodon idella) via the Nrf2 signaling pathway after Aeromonas hydrophila infection

BackgroundMannan oligosaccharides (MOS) are recommended as aquaculture additives owing to their excellent antioxidant properties. In the present study, we examined the effects of dietary MOS on the head kidney and spleen of grass carp (Ctenopharyngodon idella) with Aeromonas hydrophila infection.MethodsA total of 540 grass carp were used for the study. They were administered six gradient dosages of the MOS diet (0, 200, 400, 600, 800, and 1,000 mg/kg) for 60 d. Subsequently, we performed a 14-day Aeromonas hydrophila challenge experiment. The antioxidant capacity of the head kidney and spleen were examined using spectrophotometry, DNA fragmentation, qRT-PCR, and Western blotting.ResultsAfter infection with Aeromonas hydrophila, 400–600 mg/kg MOS supplementation decreased the levels of reactive oxygen species, protein carbonyl, and malonaldehyde and increased the levels of anti-superoxide anion, anti-hydroxyl radical, and glutathione in the head kidney and spleen of grass carp. The activities of copper-zinc superoxide dismutase, manganese superoxide dismutase, catalase, glutathione S-transferase, glutathione reductase, and glutathione peroxidase were also enhanced by supplementation with 400–600 mg/kg MOS. Furthermore, the expression of most antioxidant enzymes and their corresponding genes increased significantly with supplementation of 200–800 mg/kg MOS. mRNA and protein levels of nuclear factor erythroid 2-related factor 2 also increased following supplementation with 400–600 mg/kg MOS. In addition, supplementation with 400–600 mg/kg MOS reduced excessive apoptosis by inhibiting the death receptor pathway and mitochondrial pathway processes.ConclusionsBased on the quadratic regression analysis of the above biomarkers (reactive oxygen species, malondialdehyde, and protein carbonyl) of oxidative damage in the head kidney and spleen of on-growing grass carp, the recommended MOS supplementation is 575.21, 557.58, 531.86, 597.35, 570.16, and 553.80 mg/kg, respectively. Collectively, MOS supplementation could alleviate oxidative injury in the head kidney and spleen of grass carp infected with Aeromonas hydrophila.

ALS drug receives advisory panel’s thumbs-up

A panel of external advisers to the US Food and Drug Administration has given Biogen’s amyotrophic lateral sclerosis (ALS) treatment, tofersen, its unanimous support for accelerated approval. The recommendation, made March 22, came despite the drug’s failed Phase 3 trial; instead, it is based on biomarker data. The copper zinc superoxide dismutase 1 ( SOD1 ) mutation  is the second-most-common genetic mutation that causes familial ALS. Though the mutation affects only about 330 people in the US, they have heartbreaking stories to tell: during the hearing, one patient shared that her family has recorded 33 deaths from ALS across seven generations and counting. The first drug candidate for SOD1 -ALS, Biogen’s tofersen is an antisense oligonucleotide that binds to messenger RNA to silence the expression of the faulty SOD1 protein. But a reduced protein level doesn’t necessarily translate to improvement among patients. In a 6-month double-anonymous Phase 3 trial

Roles of the Zinc Ion and Water Molecule in the Active Site of the Copper-Zinc SOD Catalyst

In this work, we study the effect of a water molecule and a zinc ion on the catalytic activity of copper-zinc superoxide dismutase by computer simulation at the level of density functional theory using the PBE functional and the def2-SVPD and def2-TZVPD basis sets. Assessment is carried out in two directions. The first is a comparison of the main characteristics of electron transfer according to Marcus in the presence and absence of a water molecule in the active site. The second is the topological analysis of the electron density of the ligand environment of the copper ion according to Bader. It has been found that the presence of a water molecule and a zinc ion next to a copper ion has little effect on the primary stage of catalysis, the reduction of the copper ion. However, their presence significantly affects the course of the second stage of the catalytic cycle in the oxidation of copper. The water molecule is involved as a proton carrier. It may be present next to the copper ion during primary electron transfer. The water molecule leaves the first coordination sphere of copper after the initial electron transfer; otherwise, it forms a strong bond with the nitrogen atom, interrupting the electron transfer, according to the topological analysis. The presence of a water molecule near copper significantly impairs the secondary electron transfer, and the catalytic cycle is generally blocked.

Changes in a Protein Profile Can Account for the Altered Phenotype of the Yeast Saccharomyces cerevisiae Mutant Lacking the Copper-Zinc Superoxide Dismutase.

Copper-zinc superoxide dismutase (SOD1) is an antioxidant enzyme that catalyzes the disproportionation of superoxide anion to hydrogen peroxide and molecular oxygen (dioxygen). The yeast Saccharomyces cerevisiae lacking SOD1 (Δsod1) is hypersensitive to the superoxide anion and displays a number of oxidative stress-related alterations in its phenotype. We compared proteomes of the wild-type strain and the Δsod1 mutant employing two-dimensional gel electrophoresis and detected eighteen spots representing differentially expressed proteins, of which fourteen were downregulated and four upregulated. Mass spectrometry-based identification enabled the division of these proteins into functional classes related to carbon metabolism, amino acid and protein biosynthesis, nucleotide biosynthesis, and metabolism, as well as antioxidant processes. Detailed analysis of the proteomic data made it possible to account for several important morphological, biochemical, and physiological changes earlier observed for the SOD1 mutation. An example may be the proposed additional explanation for methionine auxotrophy. It is concluded that protein comparative profiling of the Δsod1 yeast may serve as an efficient tool in the elucidation of the mutation-based systemic alterations in the resultant S. cerevisiae phenotype.

Bone Marrow Mesenchymal Stem-Cell-Derived Exosomes Ameliorate Deoxynivalenol-Induced Mice Liver Damage.

Deoxynivalenol (DON) is a kind of Fusarium toxin that can cause a variety of toxic effects. DON is mainly metabolized and detoxified by the liver. When the concentration of DON exceeds the metabolic capacity of the liver, it will trigger acute or chronic damage to the liver tissue. Previous studies demonstrated that bone marrow mesenchymal stem-cell-secreted exosomes (BMSC-exos) reduce liver injury. Therefore, we issue a hypothesis that in vitro-cultured rat BMSC-secreted exos could ameliorate liver damage after 2 mg/kg bw/day of DON exposure. In total, 144 lipids were identified in BMEC-exos, including high polyunsaturated fatty acid (PUFA) levels. BMSC-exos treatment alleviated liver pathological changes and decreased levels of alanine aminotransferase, aspartate aminotransferase, inflammatory factors interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and lipid peroxidation. Otherwise, low or high BMSC-exos treatment obviously changes DON-induced hepatic oxylipin patterns. According to the results from our correlation network analysis, Pearson correlation coefficient analysis, and hierarchical clustering analysis, the top 10% oxidized lipids can be classified into two categories: one that was positively correlated with copper-zinc superoxide dismutase (Cu/Zn SOD) and another that was positively correlated with liver injury indicators. Altogether, BMSC-exos administration maintained normal liver function and reduced oxidative damage in liver tissue. Moreover, it could also significantly change the oxylipin profiles under DON conditions.

Evidence and Metabolic Implications for a New Non-Canonical Role of Cu-Zn Superoxide Dismutase

Copper-zinc superoxide dismutase 1 (SOD1) has long been recognized as a major redox enzyme in scavenging superoxide radicals. However, there is little information on its non-canonical role and metabolic implications. Using a protein complementation assay (PCA) and pull-down assay, we revealed novel protein-protein interactions (PPIs) between SOD1 and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein zeta (YWHAZ) or epsilon (YWHAE) in this research. Through site-directed mutagenesis of SOD1, we studied the binding conditions of the two PPIs. Forming the SOD1 and YWHAE or YWHAZ protein complex enhanced enzyme activity of purified SOD1 in vitro by 40% (p < 0.05) and protein stability of over-expressed intracellular YWHAE (18%, p < 0.01) and YWHAZ (14%, p < 0.05). Functionally, these PPIs were associated with lipolysis, cell growth, and cell survival in HEK293T or HepG2 cells. In conclusion, our findings reveal two new PPIs between SOD1 and YWHAE or YWHAZ and their structural dependences, responses to redox status, mutual impacts on the enzyme function and protein degradation, and metabolic implications. Overall, our finding revealed a new unorthodox role of SOD1 and will provide novel perspectives and insights for diagnosing and treating diseases related to the protein.

SOD2 in platelets: with age comes responsibility

SOD2 in platelets: with age comes responsibility

Low oxygen tension affects proliferation and senescence of caprine bone marrow mesenchymal stem cells in in vitro culture condition

The culture system of bone marrow mesenchymal stem cells (bmMSCs) in the normoxic environment does not imitate the hypoxic milieu of typical biological conditions, thus hypoxic culture conditions may improve survival, and growth attributes of bmMSCs during in vitro culture. Therefore, the present study was conducted at ICAR-CIRG, Makhdoom during year 2020 with the objective to investigate the changes in biological characteristics of cultured caprine bmMSCs (cbmMSCs) including the cellular senescence, survival, rate of proliferation, immuno-phenotypic characteristics, and gene expression pattern in a normal and hypoxic microenvironment condition. For this, cbmMSCs isolated from bone marrow collected from iliac crest were enriched and grown under either hypoxic (5% O2) or normoxic (20% O2) conditions. Thereafter, the outcome of hypoxic (5% O2) culturing of cbmMSCs on growth characteristics, proliferation, senescence, and expression profile of important stemness-associated (OCT-4) and oxidative stress [glutathione peroxidase (GPx1) and copper-zinc superoxide dismutase (CuZnSOD)] marker genes was evaluated. cbmMSCs cultivated in hypoxic conditions showed higher proliferation and decreased population doubling time and senescence-associated β-GAL expression; however, the immune-phenotypic characteristics of the cells remain unchanged. Furthermore, the culture of cbmMSCs in hypoxia increased the expression of OCT-4, GPx1, and CuZnSOD, compared with the cells grown under normoxia. In conclusion, the culture condition with low O2 level improved the growth characteristics and proliferation of cbmMSCs. These outcomes would provide information to formulate strategies for the collection and efficient in vitro expansion of bmMSCs from goats and other farm animals before their downstream applications.

Organic copper promoted copper accumulation and transport, enhanced low temperature tolerance and physiological health of white shrimp (Litopenaeus vannamei Boone, 1931)

This study was conducted to assess the effects of dietary copper source and level on hematological parameters, copper accumulation and transport, resistance to low temperature, antioxidant capacity and immune response of white shrimp (Litopenaeus vannamei Boone, 1931). Seven experimental diets with different copper sources and levels were formulated: C, no copper supplementation; S, 30 mg/kg copper in the form of CuSO4·5H2O; SO, 15 mg/kg copper in CuSO4·5H2O + 7.5 mg/kg copper in Cu-proteinate; O1, O2, O3 and O4, 10, 20, 30 and 40 mg/kg copper in the form of Cu-proteinate, respectively. A total of 840 shrimp (5.30 ± 0.04 g) were randomly distributed to 21 tanks (3 tanks/diet, 40 shrimp/tank). An 8-week feeding trial was conducted. The results showed that there was no significant difference in growth performance and whole shrimp chemical compositions among all groups. Compared with inorganic copper, dietary organic copper (O2 and O3) increased total protein, albumin, and glucose content of plasma, while decreased triglyceride and total cholesterol of plasma. Copper concentration in plasma and muscle and gene expression of metallothionein and copper-transporting ATPase 2 like in hepatopancreas were higher in shrimp fed organic copper (SO, O2, O3 and O4). The lowest mortality after low temperature (10 °C) challenge test was observed in the O2 and O3 groups. Organic copper (SO, O2, O3 and O4) significantly enhanced the antioxidant capacity (in terms of higher activities of total superoxide dismutase, copper zinc superoxide dismutase, catalase, glutathione peroxidase and total antioxidant capacity, lower malondialdehyde concentration of plasma, and up-regulated gene expression of superoxide dismutase, copper zinc superoxide dismutase, catalase and glutathione peroxidase of hepatopancreas). Organic copper (SO, O2, O3 and O4) enhanced the immune response (in terms of higher number of total hemocytes, higher activities of acid phosphatase, alkaline phosphatase, phenoloxidase, hemocyanin and lysozyme in plasma, and higher gene expressions of alkaline phosphatase, lysozyme and hemocyanin in hepatopancreas). Inorganic copper (Diet S) also had positive effects on white shrimp compared with the C diet, but the SO, O2, O3 and O4 diets resulted in better results, among which the O2 diet appeared to be the best one. In conclusion, organic copper was more beneficial to shrimp health than copper sulfate.

Effects of different low-dose of insulin glargine on antioxidation of organs in burned rats with delayed resuscitation

To study the antioxidant protective effects of different low-dose of insulin glargine on organs of burned rats with delayed resuscitation. Forty male Sprague-Dawley (SD) rats were randomly divided into sham group, delayed resuscitation control group, and insulin glargine 0.5, 1.0, and 2.0 U groups, with 8 rats in each group. The rats were immersed in hot water (95.0±0.5) centigrade for 15 s to establish the third-degree scald model with 30% total body surface area. The rats in the sham group were immersed in a 37 centigrade water bath for 15 s. Insulin glargine (0.5, 1.0, 2.0 U×kg-1×d-1) was injected subcutaneously in corresponding insulin glargine group 2 hours after injury, and the same amount of normal saline was injected intraperitoneally in the delayed resuscitation control group. Intraperitoneal injection of normal saline 40 mL/kg simulated delayed resuscitation 6 hours after injury in all groups. Abdominal aortic blood samples, heart and kidney tissue were collected immediately after simulating burn in the sham group, and 24 hours after burn in other four groups. The blood glucose, myocardial enzymes [lactate dehydrogenase (LDH), creatine kinase (CK), α-hydroxybutyrate dehydrogenase (α-HBDH), and aspartate aminotransferase (AST)] and renal function indexes [blood urea nitrogen (BUN) and serum creatinine (SCr)] were measured by spectrophotometry, and the isoenzyme MB of creatine kinase (CK-MB) level was determined by immunosuppression method to evaluate the effects of different low-dose insulin glargine intervention on blood glucose, cardiac and renal functions in scalded rats with delayed resuscitation. The oxidative and antioxidant indices [xanthine oxidase (XOD), myeloperoxidase (MPO), copper-zinc superoxide dismutase (CuZn-SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and total antioxidant capacity (T-AOC)] from the heart and kidney tissues of rats were detected by spectrophotometry to analyze the antioxidant effects of different low-dose insulin glargine interventions. Compared with the sham group, the blood glucose of the rats in the delayed resuscitation control group was significantly increased, the heart and kidney functions were significantly reduced, the oxidation capacity was enhanced, and the antioxidant indicators were significantly reduced. After the intervention of insulin glargine, with the increase of insulin glargine dose, the blood glucose, myocardial enzyme and renal function indicators of rats showed a gradual downward trend, the oxidation indicators continued to decrease, and the antioxidant indicators showed a gradual upward trend. When the dose was 2.0 U×kg-1×d-1, the blood glucose, LDH, CK, CK-MB, α-HBDH, AST, BUN, SCr, XOD and MPO were significantly lower than those in the delayed resuscitation control group [blood glucose (mmol/L): 5.91±0.25 vs. 11.76±0.36, LDH (U/L): 3 332.12±51.61 vs. 5 008.94±490.12, CK (kU/L): 0.49±0.03 vs. 0.85±0.04, CK-MB (U/L): 125.40±12.19 vs. 267.52±11.63, α-HBDH (U/L): 122.99±5.37 vs. 240.85±13.99, AST (U/L): 11.95±1.81 vs. 17.87±1.57, BUN (mmol/L): 4.72±0.15 vs. 7.16±0.34, SCr (μmol/L): 87.11±6.51 vs. 137.50±11.36, XOD (U/g): 166.29±3.27 vs. 204.90±4.82 in heart tissue, 63.51±1.46 vs. 79.69±1.75 in kidney tissue, MPO (U/g): 1.05±0.02 vs. 1.55±0.06 in heart tissue, 1.04±0.04 vs. 1.87±0.01 in kidney tissue, all P < 0.05], and CuZn-SOD, CAT, GSH-Px and T-AOC were significantly higher than those in the delayed resuscitation control group [CuZn-SOD (kU/g): 82.95±2.69 vs. 56.52±2.26 in heart tissue, 94.50±2.73 vs. 62.02±1.66 in kidney tissue, CAT (U/g): 36.07±2.01 vs. 15.15±2.22 in heart tissue, 184.49±4.53 vs. 156.02±3.96 in kidney tissue, GSH-Px (kU/g): 231.93±8.03 vs. 179.48±3.15 in heart tissue, 239.63±7.30 vs. 172.20±2.09 in kidney tissue, T-AOC (kU/g): 4.85±0.23 vs. 2.71±0.11 in heart tissue, 5.51±0.08 vs. 3.50±0.07 in kidney tissue, all P < 0.05]. Different low-dose of insulin glargine (≤ 2.0 U×kg-1×d-1) could exert antioxidant protection on the heart and kidney of rats with delayed resuscitation after burns, with a dose-dependent manner.

Resveratrol in the Hypothalamic Paraventricular Nucleus Attenuates Hypertension by Regulation of ROS and Neurotransmitters.

Background: The hypothalamic paraventricular nucleus (PVN) is an important nucleus in the brain that plays a key role in regulating sympathetic nerve activity (SNA) and blood pressure. Silent mating-type information regulation 2 homolog-1 (sirtuin1, SIRT1) not only protects cardiovascular function but also reduces inflammation and oxidative stress in the periphery. However, its role in the central regulation of hypertension remains unknown. It is hypothesized that SIRT1 activation by resveratrol may reduce SNA and lower blood pressure through the regulation of intracellular reactive oxygen species (ROS) and neurotransmitters in the PVN. Methods: The two-kidney one-clip (2K1C) method was used to induce renovascular hypertension in male Sprague-Dawley rats. Then, bilaterally injections of vehicle (artificial cerebrospinal fluid, aCSF, 0.4 μL) or resveratrol (a SIRT1 agonist, 160 μmol/L, 0.4 μL) into rat PVN were performed for four weeks. Results: PVN SIRT1 expression was lower in the hypertension group than the sham surgery (SHAM) group. Activated SIRT1 within the PVN lowered systolic blood pressure and plasma norepinephrine (NE) levels. It was found that PVN of 2K1C animals injected with resveratrol exhibited increased expression of SIRT1, copper-zinc superoxide dismutase (SOD1), and glutamic acid decarboxylase (GAD67), as well as decreased activity of nuclear factor-kappa B (NF-κB) p65 and NAD(P)H oxidase (NOX), particularly NOX4. Treatment with resveratrol also decreased expression of ROS and tyrosine hydroxylase (TH). Conclusion: Resveratrol within the PVN attenuates hypertension via the SIRT1/NF-κB pathway to decrease ROS and restore the balance of excitatory and inhibitory neurotransmitters.

Heat Shock Proteins and Antioxidant Genes Involved in Heat Combined with Drought Stress Responses in Perennial Rye Grass.

The frequent occurrence of heat and drought stress can severely reduce agricultural production of field crops. In comparison to a single stress, the combination of both heat (H) and drought (D) further reduce plant growth, survival and yield. This study aimed to explore the transcriptional responses of heat shock protein (HSP) and antioxidant genes under H combined D stress in perennial rye grass (PRG). The results demonstrated that oxidative stress indicators (hydrogen peroxide, lipid peroxidation) significantly increased, particularly in the case of combined H and D treatment, suggesting that oxidative stress-induced damage occurred in plants under the combined stresses. Transcriptional responses of heat shock protein 70 (HSP70), heat shock protein 90-6 (HSP90-6), and the mitochondrial small heat shock protein HSP26.2 (HSP26.2) occurred rapidly, and showed high level of expression particularly under H and D stress. Antioxidant genes including ascorbate peroxidase (APX), glutathione reductase (GR), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), catalase (CAT), copper–zinc superoxide dismutase (Cu/ZnSOD), peroxidase (POD), ferredoxin–thioredoxin (FTR), thioredoxin (Trx), 2-cysteine peroxiredoxin (2-Cys Prx) showed response to combined H and D, followed by either D or H stress alone in rye grass. An interactome map revealed the close partnership of these heat shock protein genes and antioxidant genes, respectively. These candidate genes were predominantly linked to stress responses and antioxidant defense in plants. These findings may advance our understanding about the HSP and the antioxidant genes underlying combined abiotic stress response and tolerance in perennial rye grass.

Effects of Exogenous Linoleic Acid on Barley (Hordeum vulgare L.) Seedlings Under Salinity

Salt stress adversely affects plants and causes different levels of morphological, physiological, biochemical, and molecular changes at different growth stages. Polyunsaturated fatty acids (PUFAs), such as linoleic acid, are main components of membrane lipids and determine the fluidity and stability of the cell membrane. In addition, PUFAs have a crucial role in maintaining the structure and function of the cell membrane which is damaged by salinity. There may be a relationship between level of PUFAs in membrane lipids and salinity tolerance. The present study was carried out to examine the effects of exogenous application of 0.5 mM linoleic acid (LA) on barley seedlings (Hordeum vulgare L. cv. Martı) grown in hydroponic conditions under 160 mM NaCl. The treatment with LA ameliorated the stress generated by NaCl by increasing osmolyte level and decreasing ion leakage percentage and H2O2 content within hours. Besides, LA significantly enhanced expression of salt-responsive transcription factor HvDRF2 and ROS scavenger gene HvMT2 as 105- and 40-fold, respectively, in the leaves of barley seedlings under salinity conditions. While LA slightly increased the gene expression of ascorbate peroxidase (HvAPX), glutathione S-transferase (HvGST6) and copper zinc superoxide dismutase (HvCu/ZnSOD) in the roots of barley seedlings, the expression of these genes was not changed in the leaves under salinity compared to salt-stressed samples. This study provides novel insights for effects of LA on improvement of salinity tolerance in barley.

Cu-Zn SOD suppresses epilepsy in pilocarpine-treated rats and alters SCN2A/Nrf2/HO-1 expression

Copper-zinc superoxide dismutase (Cu-Zn SOD) is downregulated in epilepsy, however, the role of Cu-Zn SOD in epilepsy remains unclear. Based on the pilocarpine hydrochloride-induced rat model of epilepsy, cortical-striatum brain slices of rats were examined based on field excitatory post-synaptic potentials. Pathological changes were observed by transmission electron microscope. Also using SH-SY5Y cells, flow cytometry and TUNEL staining were applied to investigate cell apoptosis, and ELISA was applied to detect SOD activity. In addition, qRT-PCR and western blot were performed to detect SCN2A/Nrf2/HO-1 gene and protein expression levels, respectively. Cu-Zn SOD over-expression suppressed epilepsy in vivo. In addition, Cu-Zn SOD knockdown notably decreased SOD activity and induced apoptosis in SH-SY5Y cells. Moreover, Cu-Zn SOD silencing decreased the levels of SCN2A, Nrf2 and HO-1. Lastly, Cu-Zn SOD was shown to modulate the NaV1.2/Nrf2/HO-1 axis in rats. In this model, Cu-Zn SOD attenuated epilepsy and was shown to alter the expression level of proteins of the NaV1.2 /Nrf2/HO-1 signalling pathway, indicating that Cu-Zn SOD might be a target for the treatment of epilepsy.

Glycine-serine-rich effector PstGSRE4 in Puccinia striiformis f. sp. tritici inhibits the activity of copper zinc superoxide dismutase to modulate immunity in wheat.

Puccinia striiformis f. sp. tritici (Pst) secretes an array of specific effector proteins to manipulate host immunity and promote pathogen colonization. In a previous study, we functionally characterized a glycine-serine-rich effector PstGSRE1 with a glycine-serine-rich motif (m9). However, the mechanisms of glycine-serine-rich effectors (GSREs) remain obscure. Here we report a new glycine-serine-rich effector, PstGSRE4, which has no m9-like motif but inhibits the enzyme activity of wheat copper zinc superoxide dismutase TaCZSOD2, which acts as a positive regulator of wheat resistance to Pst. By inhibiting the enzyme activity of TaCZSOD2, PstGSRE4 reduces H2O2 accumulation and HR areas to facilitate Pst infection. These findings provide new insights into the molecular mechanisms of GSREs of rust fungi in regulating plant immunity.

Hydrogen Sulfide Modulates Salinity Stress in Common Bean Plants by Maintaining Osmolytes and Regulating Nitric Oxide Levels and Antioxidant Enzyme Expression

The purpose of the present study is to investigate the role of hydrogen sulfide (H2S), in improving resistance to common bean salt stress. Method shows that common bean seeds were soaked in water and in two concentrations of sodium hydrosulfide (50 and 100 µM) for 8 h. After 25 days from sowing, the pots were irrigated with water and with two concentrations of NaCl (75 and 150 mM) until the end of the experiment. Results revealed that H2S relieved salt stress by decreasing growth inhibition and photosynthetic characteristics, and increasing osmolyte contents (proline and glycine betaine). Furthermore, H2S reduced oxidative damage by lowering lipid peroxidation, electrolyte leakage, and reactive oxygen species production such as hydrogen peroxide, hydroxyl radicals, and superoxide anion by increasing non-enzymatic antioxidants such as ascorbic acid and glutathione, as well as enzymatic antioxidants such as superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), ascorbate peroxidase (APX), glutathione reductase (GR), and nitrate reductase (NR). Meanwhile, salt stress and H2S application increased the endogenous level of H2S, which was accompanied by an increase in nitric oxide concentration. H2S, in particular, maintained sodium (Na+) and potassium (K+) homeostasis in the presence of excess NaCl. In general, H2S effectively reduced oxidative stress in common bean plants by increasing relative expression levels of copper-zinc superoxide dismutase (Cu-ZnSOD), CAT, and glutathione S-transferase (GST). Applying H2S to common bean plants could protect them from salinity stress by maintaining the Na+/K+ balance, boosting endogenous H2S and nitric oxide levels, and preventing oxidative damage by increasing antioxidant activity.