Increased Antioxidant Enzyme Research Articles

The effects and mechanisms of dietary ferulic acid (FA) and dihydromyricetin (DMY) on growth and physiological responses of the shrimp (Litopenaeus vannamei)

The aim of this study was to comprehensively investigate the impact of ferulic acid (FA) or FA-dihydromyricetin (DMY) complex on the growth and physiological responses of Litopenaeus vannamei and their underlying mechanisms, as well as to examine whether the combined use of FA and DMY exhibits synergistic effects. A total of 1050 healthy shrimp were randomly allocated into 15 tanks, three tanks per group. The shrimp were provided with five different diets for 8 weeks. After different feeding experiments, a challenge test lasting for seven days was conducted using Vibrio parahaemolyticus (VP). The results of growth parameters showed that there were significant differences between all treatment groups and the control group in weight gain rate (WG), specific growth rate (SGR) and feed conversion ratio (FCR). Additionally, the hepatopancreas index (HSI) and condition factor (CF) were significantly increased in FD2 group. The activities of protease, lipase and amylase in hepatopancreas were significantly elevated in the FD1 group compared to the control group. Decreases in body crude fat content and plasma lipid parameters suggested that both FA and FA-DMY complex can reduce lipid deposition. Furthermore, dietary FA or FA-DMY complex could enhance lipid metabolism by regulating the expression of genes involved in fatty acid and triglyceride metabolism in hepatopancreas. Results of antioxidant capacity and immune responses indicated that the addition of FA or FA-DMY complex in the diet enhanced physiological responses in shrimp, as evidenced by increased antioxidant enzyme activities, elevated immune parameters, and upregulated the expression of immune-related genes in hemocytes and intestine. Additionally, dietary FA could improve intestinal health by modulating the composition and richness of intestinal microbiota. The results of the safety assessment showed that both FA and low-level FA-DMY complex had positive effects on the health status of hepatopancreas, but the dietary combination of FA and DMY (100 mg/kg + 200 mg/kg) could induce hepatopancreatic damage. In summary, dietary FA or FA-DMY complex has the potential to enhance the growth and physiological responses of L. vannamei. Moreover, the dietary combination of FA and DMY at appropriate levels had synergistic effects.

Combined interaction between the diazotrophic Niallia circulans strain YRNF1 and arbuscular mycorrhizal fungi in promoting growth of eggplant and mitigating root rot stress caused by Rhizoctonia solani

Rhizoctonia root rot of eggplant, caused by Rhizoctonia solani, is an economically important disease. Niallia circulans YRNF1 and arbuscular mycorrhizal fungi (AMF) were assessed for their biocontrol and biofertilizing effects against R. solani, as potential replacements for synthetic fungicides and fertilizers. The diazotrophic N. circulans YRNF1, isolated from soil, reduced in vitro growth of R. solani by 42%. GC-MS analysis of culture filtrate of N. circulans YRNF1 detected bioactive compounds, including butyric acid (85%) and ethylene glycol (8%). In greenhouse experiments, combined application of N. circulans YRNF1 and AMF reduced the severity of eggplant root rot by 26%. This combined treatment triggered the transcriptional expression of five resistance genes (JERF3, PAL1, C3H, CHI2, and HQT) in the treated eggplants. Biochemical analyses of the infected eggplant roots treated with the combined bio-inoculants showed enhancement of the phenol content (+188%), and increased antioxidant enzyme activity, mainly of POD (+104%) and PPO (+72%). Combined application of N. circulans YRNF1 and AMF also promoted eggplant growth and improved the total NPK concentrations in treated plant leaves. Inoculation of eggplant with N. circulans YRNF1 in the presence of AMR increased the mycorrhization level. This is the first report of N. circulans and AMF as potential agents for biological control of Rhizoctonia root rot and growth promotion of eggplant.

Assessment of Hepatoprotective and Antioxidant Effect of Acioa barteri Extract (ABE) in Alloxan-Induced Diabetic Rats

This study aimed to investigate the effects of Acioa barteri extract (ABE) on hepatocellular enzyme activity, hepatic function, and antioxidant stress indices in diabetic rats induced with alloxan. The antidiabetic effect of ABE was evaluated in six experimental groups: normal controls, diabetics untreated, diabetics treated with 200mg/kg, 400mg/kg, or 800 mg/kg ABE, and diabetics treated with 3 mg/kg Glibenclamide. ABE was orally administered to induce diabetes, and alloxan-monohydrate was intraperitoneally administered. Diabetic untreated rats exhibited significantly elevated levels of alkaline phosphatase, aspartate, and alanine transaminase activities, as well as higher concentrations of total bilirubin, conjugated bilirubin, and malondialdehyde. They also showed decreased levels of total protein, albumin, globulin, and protein-bound iodine, along with reduced antioxidant enzyme activity. In contrast, diabetic rats administered ABE demonstrated reduced hepatocellular enzyme activity and improved hepatic function. These rats exhibited increased levels of total protein, globulin, and albumin, as well as higher levels of glutathione, superoxide dismutase, glutathione peroxidase, and catalase activities, compared to diabetic untreated rats. The findings suggest that ABE may help prevent oxidative stress and improve hepatic functions in diabetic rats. ABE treatment led to decreased hepatocellular enzyme activity and improved hepatic function, along with increased antioxidant enzyme activities. These results highlight the potential of ABE as a therapeutic option for diabetes-induced liver dysfunction. Further research is warranted to explore its mechanisms of action and potential clinical applications.

Isolation and characterization of novel cadmium-resistant Escherichia fergusonii ZSF-15 from industrial effluent for flocculant production and antioxidant enzyme activity.

Cadmium (Cd) is a highly toxic metal that frequently contaminates our environment. In this study, the bioflocculant-producing, cadmium-resistant Escherichia fergusonii ZSF-15 was characterized from Paharang drain, Bawa Chak, Faisalabad, Pakistan. The Cd-resistant E. fergusonii was used to determine the bioflocculant production using yeast-peptone-glycerol medium (pH 6.5) supplemented with 50mg L-1 of Cd. The culture was incubated for 3days at 37°C in a rotary shaker at 120rpm. The fermentation broth was centrifuged at 4000g for 10min after the incubation period. The maximum flocculating activity by isolate ZSF-15 was found to be 71.4% after 48h of incubation. According to the Fourier transform infrared spectroscopy analysis, the bioflocculant produced by strain ZSF-15 was comprised of typical polysaccharide and protein, i.e. hydroxyl, carboxyl, and amino groups. The strain ZSF-15 exhibited bioflocculant activity at range of pH (6-8) and temperature (35-50℃). Maximum flocculation activity (i.e. 71%) was observed at 47℃, whereas 63% flocculation production was observed at pH 8. In the present study, antioxidant enzyme profile of ZSF-15 was also evaluated under cadmium stress. A significant increase in antioxidant enzymes including superoxide dismutase (118%) and ascorbate peroxidase (28%) was observed, whereas contents of catalase (86%), glutathione transferase (13%), and peroxidase (8%) were decreased as compared to control.

The phenylpropionamide extract of hemp (Cannabis sativa L.) seed improves learning memory ability and survival rate by attenuating microglia activation and reducing amyloid deposition via the SIRT1-AMAD10 pathway in APP/PS1 mice

BackgroundFructus cannabis (Hemp seed), the dried and mature fruit of Cannabis sativa L., was reported to have effects against Alzheimer's disease (AD) in different experimental models. However, either chemical composition or mechanisms of action was not clear. Our previous work isolated and identified diverse phenylpropionamides such as cannabisin A-F, caffeoyltyramine and feryroyltyramine from hemp seed, which showed antioxidant and anti-neuroinflammatory activity in cell models. PurposeTo study the anti-AD effect and mechanism of the total phenylpropionamides (TPA) extract from hemp seed using APPswe/PS1dE9 mice model. MethodsTPA extract was prepared via extraction and column chromatography techniques, then analyzed and measured using HPLC, HPLC-MS and Folin-Ciocalteu method. The extract was administered by gavage to APPswe/PS1dE9 mice. The learning memory ability of mice were examined using new object recognition test and Morris water maze. Hematoxylin and Eosin staining was used to observe the morphology of neuronal cells in the hippocampal region of brain tissue; ELISA was used to measure the content of IL-1β, TNF-α, IL-6, superoxide dismutase (SOD), malondialdehyde (MDA) in the brain tissue; the deposition of Aβ protein was measured by immunohistochemistry and Western blotting; the activation of microglia was measured by immunofluorescence. The expression of APP, PS1, SIRT1, and ADAM10 proteins was measured by Western blotting. ResultsFolin-Ciocalteu method showed the total phenylpropionamides content was 238.03 μg caffeic acid equivalent /mg TPA. HPLC and HPLC-MS analysis showed the contents of N-trans-caffeoyltyramine, cannabisin A and B were 20.16 μg/mg, 32.16 μg/mg and 214.35 μg/mg, respectively, in TPA extract. TPA treatment significantly increased the survival rate of APP/PS1 mice, improved the learning and memory ability, reversed the neural cell damage in the hippocampal region, and reduced Aβ deposition and activated microglia in brain tissue. Meanwhile, the administration decreased the neuroinflammatory factors TNF-α, IL-6, IL-1β expression, increased antioxidant enzyme SOD activity, and attenuated MDA expression. Western blotting showed that TPA administration increased SIRT1 and ADAM10 protein expression and decreased APP and PS1 protein expression. ConclusionTPA improved learning memory capacity, increased survival rate, attenuated neuroinflammation, oxidative stress, microglia activation and hippocampal apoptosis, and reduced amyloid deposition via the SIRT1-ADAM10 pathway in APP/PS1 mice.

Morphological, Anatomical, and Physiological Characteristics of Heteroblastic Acacia melanoxylon Grown under Weak Light.

Acacia melanoxylon is a fast-growing macrophanerophyte with strong adaptability whose leaf enables heteromorphic development. Light is one of the essential environmental factors that induces the development of the heteroblastic leaf of A. melanoxylon, but its mechanism is unclear. In this study, the seedlings of A. melanoxylon clones were treated with weak light (shading net with 40% of regular light transmittance) and normal light (control) conditions for 90 d and a follow-up observation. The results show that the seedlings' growth and biomass accumulation were inhibited under weak light. After 60 days of treatment, phyllodes were raised under the control condition while the remaining compound was raised under weak light. The balance of root, stem, and leaf biomass changed to 15:11:74 under weak light, while it was 40:15:45 under control conditions. After comparing the anatomical structures of the compound leaves and phyllode, they were shown to have their own strategies for staying hydrated, while phyllodes were more able to control water loss and adapt to intense light. The compound leaves exhibited elevated levels of K, Cu, Ca, and Mg, increased antioxidant enzyme activity and proline content, and higher concentrations of chlorophyll a, carotenoids, ABA, CTK, and GA. However, they displayed a relatively limited photosynthetic capacity. Phyllodes exhibited higher levels of Fe, cellulose, lignin, IAA content, and high photosynthetic capacity with a higher maximum net photosynthetic rate, light compensation point, dark respiration rate, and water use efficiency. The comparative analysis of compound leaves and phyllodes provides a basis for understanding the diverse survival strategies that heteroblastic plants employ to adapt to environmental changes.

Nanoemulsions of Phoenix dactylifera L. (Decaffeinated) and Coffea arabica L. Extracts as a Novel Approach for the Treatment of Carbon Tetrachloride-Mediated Liver Fibrosis.

Liver fibrosis is a condition characterized by the excessive buildup of scar tissue in the liver. This scarring occurs as a result of chronic liver damage, often caused by conditions such as hepatitis, alcohol abuse, certain metabolic disorders, genetic abnormalities, autoimmunity, and noninfectious diseases such as fatty liver which leads to liver fibrosis. Nanoparticles have gained attention in recent years as potential therapeutic agents for liver fibrosis. They offer unique advantages due to their small size, large surface area, and ability to carry drugs or target specific cells or tissues. Studies have suggested that nanoemulsions may enhance drug delivery systems, enabling targeted drug delivery to specific sites in the liver and improving therapeutic outcomes. In this study, we explore the protective and therapeutic values with phytochemical profiling of the used agro-wastes decaffeinated palm date seeds (Phoenix dactylifera L., PSC) coffee and caffeinated Arabic coffee seeds (Coffea arabica L.; ACS). Both ACS and PSC extracts were converted into nanoemulsion (NE) forms using the oleic acid/Tween 80 system, which was recruited for the purpose of treating a rat model with liver fibrosis. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) were used to record the sizes, morphologies, hydrodynamic diameters, and ζ-potentials of the prepared NE-ACSE and NE-PSCE. Accordingly, the NE-ACSE and NE-PSCE imaged via TEM and their ζ-potentials were recorded at 20.7, 23.3 nm and -41.4, -28.0 mV, respectively. The antioxidant properties were determined with a DPPH scavenging assay. The synthesized NE-PSCE and NE-ACSE were employed to treat a rat model with CCl4-induced liver fibrosis, to estimate the role of each emulsion-based extract in the treatment of liver fibrosis through recording inflammatory parameters, liver functions, antioxidant enzymes, and histopathological analysis results. The nanoemulsion forms of both ACSE and PSCE provided significant increases in antioxidant enzymes, reducing inflammatory parameters, compared to other groups, where liver functions were decreased with values close to those of the control group. In conclusion, both nanoemulsions, ACSE and PSCE, provided a new avenue as therapeutic approaches for liver diseases, and further studies are encouraged to obtain maximum efficiency of treatment via the combination of both extracts.

Kaempferol promotes wound-healing in diabetic rats through antibacterial and antioxidant effects, devoid of proliferative action

The investigation of novel phytochemicals for the prevention and treatment of infections caused by multidrug-resistant pathogens is gaining attention. The current study evaluated the in-vitro antimicrobial activity of kaempferol against methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. Its in-vivo efficacy in inhibiting these pathogens was determined using an excision wound model in nicotinamide-streptozocin- -induced diabetic rats. Kaempferol displayed an inhibitory effect against the tested bacteria both in vitro and in vivo. It also healed excision wounds at a 1% (w/w) concentration. An increase in antioxidant enzymes in wounded tissue was observed on kaempferol treatment. A reduction in the MRSA and P. aeruginosa counts in wounded tissue together with a reduced epithelization period was observed when compared to the infected control. A thicker epithelium, new capillaries, and a decrease in inflammatory cells were detected by hematoxylin and eosin staining. Furthermore, an increase in collagen fibers and their deposition was observed by Masson’s trichrome staining. Kaempferol at 40 µM did not display any toxicity for human keratinocytes grown in media containing high glucose and it did not affect the expression of the pro-healing cytokines genes vascular endothelial growth factor (VEGF) and transforming growth factor-b-1 (TGFβ1). Kaempferol displayed antibacterial and antioxidant actions but did not increase the expression of proliferative genes.

Plant growth regulators mitigate oxidative damage to rice seedling roots by NaCl stress.

The aim of this experiment was to investigate the effects of exogenous sprays of 5-aminolevulinic acid (5-ALA) and 2-Diethylaminoethyl hexanoate (DTA-6) on the growth and salt tolerance of rice (Oryza sativa L.) seedlings. This study was conducted in a solar greenhouse at Guangdong Ocean University, where 'Huanghuazhan' was selected as the test material, and 40 mg/L 5-ALA and 30 mg/L DTA-6 were applied as foliar sprays at the three-leaf-one-heart stage of rice, followed by treatment with 0.3% NaCl (W/W) 24 h later. A total of six treatments were set up as follows: (1) CK: control, (2) A: 40 mg⋅ L-1 5-ALA, (3) D: 30 mg⋅ L-1 DTA-6, (4) S: 0.3% NaCl, (5) AS: 40 mg⋅ L-1 5-ALA + 0.3% NaCl, and (6) DS: 30 mg⋅ L-1 DTA-6+0.3% NaCl. Samples were taken at 1, 4, 7, 10, and 13 d after NaCl treatment to determine the morphology and physiological and biochemical indices of rice roots. The results showed that NaCl stress significantly inhibited rice growth; disrupted the antioxidant system; increased the rates of malondialdehyde, hydrogen peroxide, and superoxide anion production; and affected the content of related hormones. Malondialdehyde content, hydrogen peroxide content, and superoxide anion production rate significantly increased from 12.57% to 21.82%, 18.12% to 63.10%, and 7.17% to 56.20%, respectively, in the S treatment group compared to the CK group. Under salt stress, foliar sprays of both 5-ALA and DTA-6 increased antioxidant enzyme activities and osmoregulatory substance content; expanded non-enzymatic antioxidant AsA and GSH content; reduced reactive oxygen species (ROS) accumulation; lowered malondialdehyde content; increased endogenous hormones GA3, JA, IAA, SA, and ZR content; and lowered ABA content in the rice root system. The MDA, H2O2, and O2- contents were reduced from 35.64% to 56.92%, 22.30% to 53.47%, and 7.06% to 20.01%, respectively, in the AS treatment group compared with the S treatment group. In the DS treatment group, the MDA, H2O2, and O2- contents were reduced from 24.60% to 51.09%, 12.14% to 59.05%, and 12.70% to 45.20%. In summary, NaCl stress exerted an inhibitory effect on the rice root system, both foliar sprays of 5-ALA and DTA-6 alleviated damage from NaCl stress on the rice root system, and the effect of 5-ALA was better than that of DTA-6.

Effect of diets supplemented with coated plant essential oil on the growth performance, immunity, antioxidant activity, and fecal microbiota of weaned piglets.

This trial was conducted to compare the effect of diets supplemented with plant essential oil (PEO) and coated plant essential oil (CEO) on growth performance, immunity, antioxidant activity, and fecal microbiota of weaned piglets. A total of 360 21-day-old weaned piglets were randomly allocated into three groups, namely, CON, PEO, and CEO (basal diets supplemented with 0, 500 mg/kg PEO, and 500 mg/kg CEO, respectively) for a 4-week feeding trial. The results showed that dietary supplementation with CEO improved the average final weight and average daily gain, decreased the diarrhea rate, increased antioxidant enzyme activities, enhanced immunoglobulin concentrations, and decreased concentrations of pro-inflammatory cytokines in the serum of weaned piglets (p < 0.05). In addition, CEO addition increased the fecal concentrations of propionic acid and isovaleric acid of piglets (p < 0.05). Spearman correlation analysis showed that fecal microorganisms at the genus level were closely correlated with the volatile fatty acid concentrations. The present study indicated that PEO and CEO could improve growth performance, enhance immunity, and increase antioxidant capacity by modulating the microbial flora in weaned piglets. Moreover, CEO addition seemed to offer more positive results than of PEO addition.

Elucidating the modulatory effect of melatonin on enzyme activity and oxidative stress in wheat: a global meta-analysis.

In our comprehensive meta-analysis, we initially collected 177 publications focusing on the impact of melatonin on wheat. After meticulous screening, 40 published studies were selected, encompassing 558 observations for antioxidant enzymes, 312 for reactive oxygen species (ROS), and 92 for soluble biomolecules (soluble sugar and protein). This analysis revealed significant heterogeneity across studies (I2 > 99% for enzymes, ROS, and soluble biomolecules) and notable publication bias, indicating the complexity and variability in the research field. Melatonin application generally increased antioxidant enzyme activities [superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX)] in wheat, particularly under stress conditions, such as high temperature and heavy-metal exposure. Compared to control, melatonin application increased SOD, POD, CAT, and APX activities by 29.5, 16.96, 35.98, and 171.64%, respectively. Moreover, oxidative stress markers like hydrogen peroxide (H2O2), superoxide anion (O2), and malondialdehyde (MDA) decreased with melatonin by 23.73, 13.64, and 21.91%, respectively, suggesting a reduction in oxidative stress. The analysis also highlighted melatonin's role in improving carbohydrate metabolism and antioxidant defenses. Melatonin showed an overall increase of 12.77% in soluble sugar content, and 22.76% in glutathione peroxidase (GPX) activity compared to the control. However, the effects varied across different wheat varieties, environmental conditions, and application methods. Our study also uncovered complex relationships between antioxidant enzyme activities and H2O2 levels, indicating a nuanced regulatory role of melatonin in oxidative stress responses. Our meta-analysis demonstrates the significant role of melatonin in increasing wheat resilience to abiotic stressors, potentially through its regulatory impact on antioxidant defense systems and stress response.

Dietary intakes of vitamin D promote growth performance and disease resistance in juvenile grass carp (Ctenopharyngodon idella).

Vitamin D3 (VD3) is an essential nutrient for fish and participates in a variety of physiological activities. Notably, both insufficient and excessive supplementation of VD3 severely impede fish growth, and the requirements of VD3 for fish vary considerably in different species and growth periods. The present study aimed to evaluate the appropriate requirements of VD3 for juvenile grass carp (Ctenopharyngodon idella) according to growth performance and disease prevention capacity. In this study, diets containing six supplemental levels of VD3 (0, 300, 600, 1200, 2400, and 4800IU/kg diet) were formulated to investigate the effect(s) of VD3 on the growth performance, antioxidant enzyme activities, and antimicrobial ability in juvenile grass carp. Compared with the VD3 deficiency group (0IU/kg), the supplementation of 300-2400IU/kg VD3 significantly enhanced growth performance and increased antioxidant enzyme activities in the fish liver. Moreover, dietary supplementation of VD3 significantly improved the intestinal health by manipulating the composition of intestinal microbiota in juvenile grass carp. In agreement with this notion, the mortality of juvenile grass carp fed with dietary VD3 was much lower than that in VD3 deficient group upon infection with Aeromonas hydrophila. Meanwhile, dietary supplementation of 300-2400IU/kg VD3 reduced bacterial load in the spleen and head kidney of the infected fish, and 1200IU/kg VD3 supplementation could decrease enteritis morbidity and increase lysozyme activities in the intestine. These findings strengthened the essential role of dietary VD3 in managing fish growth and antimicrobial capacity. Additionally, based on weight gain ratio and lysozyme activities, the appropriate VD3 requirements for juvenile grass carp were estimated to be 1994.80 and 2321.80IU/kg diet, respectively.

AnDREB5.1, a A5 group DREB gene from desert shrub Ammopiptanthus nanus, confers osmotic and cold stress tolerances in transgenic tobacco.

The Dehydration-Responsive Element Binding (DREB) subfamily of transcription factors plays crucial roles in plant abiotic stress response. Ammopiptanthus nanus (A. nanus) is an eremophyte exhibiting remarkable tolerance to environmental stress and DREB proteins may contribute to its tolerance to water deficit and low-temperature stress. In the present study, an A. nanus DREB A5 group transcription factor gene, AnDREB5.1, was isolated and characterized in terms of structure and function in abiotic stress tolerance. AnDREB5.1 protein is distributed in the nucleus, possesses transactivation capacity, and is capable of binding to DRE core cis-acting element. The transcription of AnDREB5.1 was induced under osmotic and cold stress. Tobacco seedlings overexpressing AnDREB5.1 displayed higher tolerance to cold stress, osmotic stress, and oxidative stress compared to wild-type tobacco (WT). Under osmotic and cold stress, overexpression of AnDREB5.1 increased antioxidant enzyme activity in tobacco leaves, inhibiting excessive elevation of ROS levels. Transcriptome sequencing analysis showed that overexpression of AnDREB5.1 raised the tolerance of transgenic tobacco seedlings to abiotic stress by regulating multiple genes, including antioxidant enzymes, transcription factors, and stress-tolerant related functional genes like NtCOR413 and NtLEA14. This study provides new evidence for understanding the potential roles of the DREB A5 subgroup members in plants.

Redox-associated changes in healthy individuals at risk of Alzheimer's disease. A ten-year follow-up study

Carrying an allele 4 of the apolipoprotein E (ApoE) is the best-established genetic risk factor to develop Alzheimer's disease (AD). Fifty percent of ApoE4/4 individuals develop the disease at 70 years of age. ApoE3/4 carriers have a lower risk of developing the disease, still 50% of them suffer AD at around 80 years. In a previous study we showed that healthy young individuals, who had a parent with AD and were carriers of at least one ApoE4 allele displayed reductive stress. This was evidenced as a decrease in oxidative markers, such as oxidized glutathione, p-p38, and NADP+/NADPH ratio, and an increase of antioxidant enzymes, such as glutathione peroxidase (Gpx1) and both the catalytic and regulatory subunits of glutamyl-cysteinyl (GCLM and GCLC). Moreover, we found an increase in stress-related proteins involved in tau physiopathology.Now, 10 years later, we have conducted a follow-up study measuring the same parameters in the same cohort. Our results show that reductive stress has reversed, as we could now observe an increase in lipid peroxidation and in the oxidation of glutathione along with a decrease in the expression of Gpx1 and SOD1 antioxidant enzymes in ApoE4 carriers. Furthermore, we found an increase in plasma levels of IL1β levels and in PKR (eukaryotic translation initiation factor 2 alpha kinase 2) gene expression in isolated lymphocytes.Altogether, our results suggest that, in the continuum of Alzheimer's disease, people at risk of developing the disease go through different redox phases, from stablished reductive stress to oxidative stress.

Olive-tree physiological response to biotic and abiotic stress fruit yield, oil quality and tolerance to Anthracnose: Doctoral thesis abstract

The olive tree is highly tolerant to water deficit and in humid climate regions, such as Uruguay, the need to irrigation is questioned. However, Uruguay's climate is characterized by high interannual variability, resulting in periods of water deficit. In the event of a water deficit, plants trigger a series of defense mechanisms to maintain cellular homeostasis, including increased antioxidant enzyme activity and cuticle thickening to prevent transpiration. These responses are common during abiotic stress and biotic stress caused by pathogen infections. Anthracnose, caused by the Colletotrichum complex, is a major disease in olive trees, leading to reduced fruit yield and oil quality. Mild drought stress has been found to activate the basal defense response, enhancing plant tolerance to pathogen infections. Therefore, the hypothesis was that exposing olive plants to moderate water deficit during the lipogenesis stage would trigger the basal defense response, increasing fruit tolerance to biotic stress caused by Colletotrichum acutatum. The study also examined whether this response was sustained under moderate water deficit. Results showed that water deficit induced anatomical and biochemical changes in olive fruits, promoting anthracnose tolerance with reduced incidence and severity of C. acutatum infection both in vitro and in vivo. Fruit weight and pulp/pit ratio decreased in response to water deficit, while cuticle thickness and fruit polyphenol content increased. An induction of enzymes related to hydrogen peroxide scavenging were observed, in particular PER and CAT. This enzymatic activity was induced by the pathogen inoculation treatment and was higher in the non-irrigated treatment. Severe water deficit resulted in significant reductions in fruit weight and oil content, but the fruits exhibited enhanced tolerance to anthracnose infection.

Development of a composite microbial agent beneficial to improve drought and salt tolerance of Glycyrrhiza uralensis Fisch.

Plant growth is enhanced by microbiological agents. In order to develop environment friendly composite microbial agent that can also improve the salt and drought tolerance of plants, the orthogonal experiment and response surface methodology were used to screen nutrients and fermentation conditions of composite microbial agent, and pot experiment was conducted to validate the application effect of optimized and complex microbial agent. Compatibility test showed that G2 (Bacillus cereus) and G5 (Bacillus pumilus) did not show any inhibitory effect on each other’s growth in nutrient agar, moreover, in both the growth promotion characteristics and the seed germination tests, G2+G5 showed a synergistic effect. The process optimization results showed that the optimal carbon and nitrogen sources for the medium nutrients was maltose and yeast extract, and the optimal carbon-nitrogen ratio was 5:1; the optimal fermentation conditions included initial pH at 5.17, inoculation amount of 2.28%, liquid volume of 105.96 mL(250 mL)−1, and incubation temperature at 30.06℃. Pot experiment showed that application with composite microbial agent was able to increase antioxidant enzyme activities, ascorbat, proline content, and reduce reactive oxygen species accumulation and membrane peroxidation of G. uralensis seedlings under salt-drought stress. In conclusion, the composite G2+G5 agent possessed remarkable synergistic effect for improve plant tolerance to drought combined with salt stress, suggesting a noticeble practical potential in agricultural practice, and it can be used to develop newtype environment friendly microbial fertilizer.

Beneficial effects of a novel polyherbal formulation on the skeletal muscle antioxidant status, inflammation, and muscle-signaling proteins in exercised rats.

Exhausting exercise can damage muscle tissue due to free radical interactions. It is hypothesized that the increase in free radicals following muscle injury, either due to oxidative damage to biomolecules or the activation of inflammatory cytokines, may lead to secondary muscle damage. This study investigated the effects of a novel joint health formula (JHF) containing bisdemethoxycurcumin-enriched curcumin, 3-O-Acetyl-11-keto-beta-boswellic acid-enriched Boswellia (AKBA), and Ashwagandha on exhaustion time, grip strength, antioxidant status, and muscle-signaling proteins in exhaustively exercised rats. Twenty-eight rats were divided into four groups: Control (C), exercise (E), E + JHF 100 (100 mg/kg), and E + JHF 200 (200 mg/kg). An increase in time to exhaustion and grip strength was recorded with JHF supplementation in a dose-dependent manner (p < 0.0001). In addition, serum and muscle lactate dehydrogenase, malondialdehyde, myoglobin, creatine kinase, and lactic acid concentrations were decreased in the groups supplemented with JHF, particularly at the high dose of JHF (200 mg/kg) (p < 0.0001 for all). JHF supplementation also increased antioxidant enzyme activities and suppressed the production of inflammatory cytokines compared to the exercise group (p < 0.0001). Moreover, JHF reduced the levels of PGC-1α, p-70S6K1, MAFbx, MuRF1, and p-mTOR proteins in muscle tissue compared to the exercise group (p < 0.05), being more effective at high doses. These findings show that JHF might reduce muscle damage by modulating antiinflammatory, antioxidant, and muscle mass regulatory pathways in exhausted training rats. At the same time, JHF improved exercise performance and grip strength.

Melatonin injection and red light irradiation affect the antioxidant response and cell damage in disk abalone (Haliotis discus hannai) exposed to high water temperatures.

The effects of red light-emitting diode (LED) light irradiation (630 nm, 0.5 W/m2) and melatonin (10-8 and 10-7 M) on oxidative stress and physiological responses in abalones exposed to high temperatures (28°C) were investigated. Changes in messenger RNA (mRNA) expressions of melatonin receptor (MT-R), heat shock protein 70 (HSP70), and antioxidant enzymes, as well as alterations in H2O2 levels in the hemolymph, were examined. The results revealed that high-temperature-stressed abalones treated with melatonin injections or exposed to red LED light showed a significant increase in MT-R mRNA expression, while HSP70 mRNA expression decreased. Notably, HSP70 mRNA expression levels in the red LED light-irradiated group were similar to those in the group injected with 10-8 M melatonin after 24 h exposure. Abalones treated with melatonin at 20°C or irradiated with red LED light exhibited decreased H2O2 levels and reduced antioxidant enzyme mRNA expression compared with those of the control group. However, the high-temperature environment induced oxidative stress in abalones, leading to increased antioxidant enzyme mRNA expression compared with that under 20°C conditions. Moreover, abalones exposed to high-temperature stress exhibited hepatopancreatic DNA damage, which was attenuated by melatonin treatment or red LED light irradiation. Hence, red LED light reduces oxidative stress, boosts antioxidant enzymes, and alleviates DNA damage in high-temperature-stressed abalones, akin to 10-8 M melatonin treatment. Therefore, considering the practical challenges of continuous melatonin administration to abalones, utilizing red LED light emerges as a practical, effective alternative to protect abalones from oxidative stress compared to 10-8 M melatonin treatment.

Protective Effect of Vitamin K2 (MK-7) on Acute Lung Injury Induced by Lipopolysaccharide in Mice.

Vitamin K2 (MK-7) has been shown to cause significant changes in different physiological processes and diseases, but its role in acute lung injury (ALI) is unclear. Therefore, in this study, we aimed to evaluate the protective effects of VK2 against LPS-induced ALI in mice. The male C57BL/6J mice were randomly divided into six groups (n = 7): the control group, LPS group, negative control group (LPS + Oil), positive control group (LPS + DEX), LPS + VK2 (L) group (VK2, 1.5 mg/kg), and LPS + VK2 (H) group (VK2, 15 mg/kg). Hematoxylin-eosin (HE) staining of lung tissue was performed. Antioxidant superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) activities, and the Ca2+ level in the lung tissue were measured. The effects of VK2 on inflammation, apoptosis, tight junction (TJ) injury, mitochondrial dysfunction, and autophagy were quantitatively assessed using Western blot analysis. Compared with the LPS group, VK2 improved histopathological changes; alleviated inflammation, apoptosis, and TJ injury; increased antioxidant enzyme activity; reduced Ca2+ overload; regulated mitochondrial function; and inhibited lung autophagy. These results indicate that VK2 could improve tight junction protein loss, inflammation, and cell apoptosis in LPS-induced ALI by inhibiting the mitochondrial dysfunction and excessive autophagy, indicating that VK2 plays a beneficial role in ALI and might be a potential therapeutic strategy.

Genome-Wide Identification and Characterization of the Superoxide Dismutase (SOD) Gene Family in Pakchoi and the Role of the BchFSD2 Gene in the Salt Stress Toleran

Superoxide dismutase (SOD) is an important antioxidant metalloenzyme present in plants that plays a vital role in plant growth and development, but studies on the SOD gene family in Pakchoi are lacking. In this study, we identified 13 SOD genes from pakchoi, including three MnSODs, five Cu/ZnSODs, and five FeSODs. Through structural analysis, the gene structures and motif patterns in the three subfamilies showed a high degree of conservation. From an evolutionary point of view, gene duplication is an important pathway driving the evolutionary development of the SOD gene family. In addition, by analyzing the structure and function of BchSOD proteins, most of the genes were shown to be involved in different developmental stages of pakchoi, and their expression was shown to be regulated by external conditions such as light, phytohormones, and abiotic stress. qPCR results revealed that BchSODs were expressed in different parts of pakchoi, and most of the genes were expressed in response to abiotic stresses (salt and drought) and hormones (GA and MeJA). In addition, the BchFSD2 gene was studied in depth, and subcellular localization confirmed that the BchFSD2 gene was expressed in plant chloroplasts. Overexpression of BchFSD2 promoted salt tolerance, limited superoxide anion and MDA production, and increased antioxidant enzyme activities in Arabidopsis. In summary, the BchSOD gene family was comprehensively analyzed in this study to provide new insights for a better understanding of BchSOD function and to improve salt tolerance in pakchoi.