Activities Of Antioxidant Enzymes Research Articles

Gamma-Aminobutyric Acid (GABA) as a Defense Booster for Wheat against Leaf Rust Pathogen (Puccinia triticina).

Wheat leaf rust, caused by Puccinia triticina, poses a growing threat to global wheat production, necessitating alternative strategies for effective disease management. This study investigated the potential of gamma-aminobutyric acid (GABA) to enhance resistance to leaf rust in two wheat cultivars: the susceptible Morocco and moderately resistant Sakha 94 cultivar. Our findings revealed that GABA significantly improved resistance in both cultivars to P. triticina, particularly in Morocco, by mitigating disease severity and reducing pustule density and size while extending both incubation and latent periods. This study assessed the effectiveness of two GABA application methods: plants received 1 mM GABA treatment, as a foliar spray, twenty-four hours prior to infection (pre-GABA), and plants received 1 mM GABA treatment both 24 h before and after infection (pre-/post-GABA), with the latter yielding significantly better results in reducing infection severity and improving plant resilience. Additionally, GABA application influenced stomatal behavior, promoting closure that may enhance resilience against leaf rust. GABA application on plants also modulated the production of reactive oxygen species (ROS). This led to a stronger oxidative burst in both susceptible and moderately resistant cultivars. GABA increased O2●- levels in guard cells and surrounding stomata, enhancing stomatal closure and the hypersensitive response. GABA enhanced the accumulation of soluble phenols and increased the activity of key antioxidant enzymes, catalase (CAT) and peroxidase (POX), which are vital for managing oxidative stress. To the best of our knowledge, this investigation represents the first report into the impact of GABA on wheat leaf rust disease.

Microalgal astaxanthin ameliorates cypermethrin-induced necroptosis and inflammation via targeting mitochondrial Ca2+ homeostasis and the ROS-NF-κB-RIPK3/MLKL axis in carp hepatocytes (Cyprinus carpio)

Cypermethrin is a toxic pesticide that has infiltrated water bodies due to its widespread use. This contamination has led to detrimental effects on the immune organs of aquatic species, including fish. The natural fat-soluble orange-red carotenoid, astaxanthin (MAT), derived from microalgae, possesses anti-inflammatory, antioxidant, and immunomodulatory properties. To elucidate the mechanism of CY induced damage to carp liver cells and assess the potential protective effects of MAT, we established a carp hepatocyte model exposed to CY and/or MAT. Hepatocytes from carp (Cyprinus carpio) were treated with either 8 μM CY or 60 μM MAT for 24 h. Upon exposure CY, a significant increase in reactive oxygen species (ROS) was observed alongside a diminution in the activities of key antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT), suggesting an impairment of cellular antioxidant capacity. Subsequently, acridine orange/ethidium bromide (AO/EB) staining and flow cytometry analysis revealed that hepatocytes exposed to CY exhibited a higher incidence of necroptosis, associated with an elevated mitochondrial Ca2+ concentration, which contributed to cellular dysfunction. Furthermore, exposure to CY also activated the ROS-NF-κB-RIPK3/MLKL signaling pathway, increasing the levels of necroptosis-related regulatory factors (RIP1, RIP3, and MLKL) in hepatocytes and the expression of inflammatory genes (IL-6, IFN-γ, IL-4, IL-1β, and TNF-α), which led to immune dysfunction in hepatocytes. The immunotoxic effects induced by CY were mitigated by MAT treatment, suggesting its potential in alleviating the aforementioned changes caused by CY. Overall, the data suggested that MAT therapy could enhance hepatocyte defenses against CY-induced necroptosis and inflammatory responses by regulating mitochondrial Ca2+ homeostasis and inhibiting the ROS-NF-κB-RIPK3/MLKL signaling cascade. This study elucidated the potential benefits of employing MAT to protect farmed fish from agrobiological hazards during CY exposure, underscoring the practical applications of MAT in aquaculture.

Epsilon-poly-l-lysine and methyl jasmonate synergistically inhibit Pseudomonas tolaasii-caused brown spot disease in postharvest button mushroom (Agaricus bisporus)

The brown spot disease, caused by Pseudomonas tolaasii is a serious disease that significantly affects the quality of Agaricus bisporus. To develop a safe and effective method to protect mushrooms from disease, the effects of epsilon-poly-l-lysine (ε-PL) and methyl jasmonate (MeJA), either alone or in combination, on brown spot disease caused by P. tolaasii in A. bisporus were investigated. Our results showed that both ε-PL (100 mg L−1) and MeJA (100 μmol L−1) effectively reduced the incidence rate and disease index, inhibited the activity of polyphenol oxidase activated by P. tolaasii, and suppressed the production of malonaldehyde, and their combination achieved a more effective effect; the reason for this result was not due to their coordinated antibacterial activity in vitro, but rather the synergistic induction of disease resistance in mushrooms. The combined treatment of ε-PL and MeJA not only increased the content of pathogenesis-related proteins (PRs), the activities of defense enzymes and antioxidant enzymes, but also enhanced the activities of phenylpropanoid pathway-related enzymes and the accumulation of total phenolic and total flavonoid substances. Furthermore, the combined treatment was also more effective in increasing JA levels and the activities of lipoxygenase and allene oxide synthase compared to treatment with either ε-PL or MeJA alone. Correlation analysis further demonstrated the important role of defense-related enzymes and PRs as well as phenylpropanoid pathway-related enzymes and metabolites in the inhibition of ε-PL and MeJA alone or in combination on the incidence rate and disease index. Taken together, our results showed that ε-PL combined with MeJA treatment has good prospects for alleviating mushroom brown spot disease.

Flavonoid-rich fraction of Monodora tenuifolia Benth seeds improves antioxidant status in male Wistar rats with streptozotocin-induced Diabetes mellitus

BackgroundOxidative stress is a disruption in the balance between free radicals and the body's natural defenses. This study investigated the modulatory effect of a flavonoid-rich fraction of Monodora tenuifolia seed (FRFMTS) on oxidative stress and antioxidant enzymes in diabetic Wistar rats. The plant seeds were collected, and identified then, hydro-ethanolic extract was obtained with 80 % (v/v) ethanol and partitioned with solvents to obtain the FRFMTS. Diabetes mellitus was induced with a single dose of 40 mg/kg bwt streptozotocin and the rats were treated according to their grouping; group 1: non-diabetic control, groups 2 and 3: non-diabetic treated with 25 mg/kg FRFMTS and 50 mg/kg FRFMTS, respectively. Group 4: diabetic control group, groups 5 and 6: diabetic groups treated with 25 mg/kg and 50 mg/kg FRFMTS, respectively, while group 7: diabetic treated with 6.67 mg/kg metformin. Antioxidant status, oxidative stress biomarkers and activities of antioxidant enzymes were determined in plasma, heart, and kidney tissues using established procedures. ResultsPlasma total antioxidant status (TAS) was increased significantly (p < 0.05) in diabetic rats upon treatment with 25 mg/kg FRFMTS (70.4 %), while 50 mg/kg FRFMTS increased TAS by 70 %. The activities of glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD) in the plasma, heart, and kidney of diabetic rats significantly decreased (61.3 %, 58.8 % and 31.4 % respectively) while lipid peroxidation (LPO) was elevated when compared with normal control groups. Flavonoid-rich fraction of M. tenuifolia at 25 mg/kg bwt and 50 mg/kg bwt significantly increased the activity GPx enzyme by 32.3 % and 72 % in plasma, while there was no significant differences in both kidney and heart of diabetic rats when compared with diabetic control groups. The treatment of diabetic rats with 25 mg/kg FRFMTS and 50 mg/kg FRFMTS improved SOD activity in the plasma (51.5 % and 69.8 %), heart (32.3 % and 27.6 %) and kidney (31.4 % and 27.1 %) respectively, and CAT activity in plasma (44.2 % and 57 %), heart (28.6 % and 60 %) and kidney (69.6 % and 76.7 %) respectively. The concentration of malondialdehyde (MDA) in lipid peroxidation assay in the heart and kidney of diabetic rats treated with 25 mg/kg FRFMTS and 50 mg/kg FRFMTS reduced significantly by (62.5 % and 71.1 % in heart), while 50 mg/kg FRFMTS significantly reduced MDA in kidney by 43.8 %. ConclusionsThe results showed that FRFMTS reduces oxidative stress and enhances the activities of antioxidant enzymes in STZ-diabetic Wistar rats. As such, FRFMTS could be useful in the management of oxidative stress-mediated diabetic complications.

Galangin prevents gentamicin-induced nephrotoxicity by modulating oxidative damage, inflammation and apoptosis in rats.

The well-known antibiotic gentamicin (GEN) works well against a variety of pathogenic bacteria, nevertheless its therapeutic use might be limited by the possibility of nephrotoxicity. The naturally occurring flavonoid galangin (GAL) has several interesting anti-inflammatory and antioxidant properties. The present study evaluated the nephroprotective effect of GAL on GEN-induced renal injury. Rats received GAL for 14 days and GEN from day 8 to day 14. There was a significant increase in serum urea and creatinine along with several histopathological changes in the kidney following GEN administration. GEN-treated rats also showed increased levels of kidney MDA and NO, and decreased GSH content and activities of antioxidant enzymes. Rats received GEN also demonstrated increased NF-κB p65, iNOS, TNF-α, IL-1β and IL-6 levels in the kidney. GAL remarkably prevented tissue injury, attenuated MDA and NO levels, improved antioxidants, and decreased levels of inflammatory mediators in the kidney of GEN-treated rats. Furthermore, GEN-administrated rats exhibited increased Bax and caspase-3 with concomitant decline in Bcl-2 levels in the kidney, an effect that GAL attenuated. In conclusion, GAL prevents GEN-induced nephrotoxicity by attenuating oxidative stress, inflammation, and apoptosis and augmenting antioxidant defense, suggesting its therapeutic potential against drug nephrotoxicity.

Biomarker responses in fish caged in a rice field during a bifenthrin application

The use of pesticides in integrated rice-fish farming could have an impact on fish health. The present study aimed to evaluate, for the first time, the biological effects of the insecticide bifenthrin on fish (Piaractus mesopotamicus and Hoplosternum littorale) using a caging experiment. Fish were divided into two sites: control (C) and bifenthrin exposure (BF). Two cages (n = 8 fish/cage) per species were placed separately at each site. The BF application (Seizer ®) was carried out with a coastal sprayer according to the BF recommended dose for rice cultivation (0.1 L/ha). After 72 hours, fish were collected, and gills, liver, brain, and muscle were dissected for the analysis of biomarkers of accumulation, oxidative stress, and neurotoxicity. In P. mesopotamicus, the main changes were observed in the muscle, where BF accumulated and induced neurotoxicity (inhibition of cholinesterase activity) and oxidative stress (activation of antioxidant enzymes, decreased glutathione levels, increased lipid peroxidation). The gills and liver also showed changes in some markers of the antioxidant system. In H. littorale, BF exposure induced changes in oxidative stress biomarkers in liver (activation of antioxidant enzymes and lipid peroxidation) and gill tissues (alteration in antioxidant markers). These results show that the use of bifenthrin in rice fields poses a risk to fish farming under current pesticide management practices. Furthermore, its use could affect other species in these agroecosystems, highlighting the need for further studies to assess the ecological and productive consequences in a context of increasing pyrethroid use worldwide.

The effects of Selenium phytotoxicity on two wheat (Triticum aestivum) cultivars differing in Se tolerance and the role of antioxidant enzymes in the tolerance mechanism

Abstract Wheat seedlings were hydroponically grown in Hoagland solution containing various levels of Se. Tolerance response to Se toxicity was investigated by determining the level of thiobarbituric acid reactive substance (TBARS), proline and chlorophyll content, the growth parameters, and the activity of antioxidant enzymes. The toxic level of Se treatment significantly retarded the seedling growth. A substantial amount of proline accumulation was also observed in response to toxic Se concentration, but it was more pronounced in putative-sensitive cultivars. Chlorophyll content significantly decreased in Se-intoxicated seedlings and increased at the lowest Se dose in both cultivars. Severe and mild chlorosis was observed in putative-sensitive and tolerant cultivars at the highest Se level. Alterations in the activities of glutathione reductase (GR, 1.6.4.2), glutathione S transferase (GST, 2.5.1.18), guaiacol peroxidase (GPX, 1.11.1.7), catalase (CAT, 1.11.1.6), and ascorbate peroxidase (APX, 1.11.1.11) and superoxide dismutase (SOD, EC 1.15.1.1) were determined. TBAR level did not significantly increase in putative tolerant cultivars as an indicator of membrane lipid peroxidation. However, a significant increase was observed in putative-sensitive cultivars in response to higher selenium concentrations. In higher Se treatment groups, CAT and GST activities significantly increased in putative Se tolerant cultivars. However, excluding SOD, the activity of all the studied enzymes was increased considerably in putative-sensitive cultivars in a dose-dependent manner. Higher antioxidant enzyme activities and a substantial amount of proline accumulation did not significantly contribute to overcoming Se phytotoxicity in wheat seedlings grown in media supplemented with toxic selenium levels.

Decreased ability to manage increases in reactive oxygen species may underlie susceptibility to arrhythmias in mice lacking Scn1b.

Scn1b plays essential roles in the heart, where it encodes β1-subunits that serve as modifiers of gene expression, cell surface channel activity, and cardiac conductivity. Reduced β1 function is linked to electrical instability in various diseases with cardiac manifestations and increased susceptibility to arrhythmias. Recently, we demonstrated that loss of Scn1b in mice leads to compromised mitochondria energetics and reactive oxygen species (ROS) production. In this study, we examined the link between increased ROS and arrhythmia susceptibility in Scn1b-/- mice. In addition, ROS-scavenging capacity can be overwhelmed during prolonged oxidative stress, increasing arrhythmia susceptibility. Therefore, we isolated whole hearts and cardiomyocytes from Scn1b-/- and Scn1b+/+ mice and subjected them to an oxidative challenge with diamide, a glutathione oxidant. Next, we analyzed gene expression and activity of antioxidant enzymes in Scn1b-/- hearts. Cells isolated from Scn1b-/- hearts died faster and displayed higher rates of ROS accumulation preceding cell death compared with those from Scn1b+/+. Furthermore, Scn1b-/- hearts showed higher arrhythmia scores and spent less time free of arrhythmia. Lastly, we found that protein expression and enzymatic activity of glutathione peroxidase is increased in Scn1b-/- hearts compared with wild type. Our results indicate that Scn1b-/- mice have decreased capability to manage ROS during prolonged oxidative stress. ROS accumulation is elevated and appears to overwhelm ROS scavenging through the glutathione system. This imbalance creates the potential for altered cell energetics that may underlie increased susceptibility to arrhythmias or other adverse cardiac outcomes.NEW & NOTEWORTHY Using an oxidative challenge, we demonstrated that isolated cells from Scn1b-/- mice are more susceptible to cell death and surges in reactive oxygen species accumulation. At the whole organ level, they were also more susceptible to the formation of cardiac arrhythmias. This may in part be due to changes to the glutathione antioxidant system.

Molybdenum nanodots act as antioxidants for photothermal therapy osteoarthritis

Osteoarthritis (OA) manifests as the degradation of cartilage and remodeling of subchondral bone. Restoring homeostasis within the joint is imperative for alleviating OA symptoms. Current interventions primarily target singular aspects, such as anti-aging, inflammation inhibition, free radical scavenging, and regeneration of cartilage and subchondral bone. Herein, we developed molybdenum nanodots (MNDs) as bionic photothermal nanomaterials to mimic the antioxidant synthase to concurrently protected cartilage and facilitate subchondral bone regeneration. With near-infrared (NIR) irradiation, MNDs effectively eliminate reactive oxygen and nitrogen species (ROS/RNS) from OA chondrocytes, thereby reversed mitochondrial dysfunction, mitigating chondrocyte senescence, and simultaneously suppresses inflammation, hence preserving the inherent homeostasis between cartilage matrix synthesis and degradation while circumventing safety concerns. RNA sequencing of OA chondrocytes treated with MNDs-NIR revealed the reinstatement of chondrocyte functionality, activation of antioxidant enzymes, anti-aging properties, and regulation of inflammation. NIR irradiation induces thermogenesis and synergistically promotes subchondral bone regeneration via MNDs, as validated through histological assessments and microcomputed tomography (Micro-CT) scans. MNDs-NIR effectively attenuate cellular senescence and inhibit inflammation in vivo, while also remodeling mitochondrial dynamics by upregulating fusion proteins and inhibiting fission proteins, thereby regulating the oxidative stress microenvironment. Additionally, MNDs-NIR exhibited remarkable therapeutic effects in alleviating articular cartilage degeneration in an OA mouse model, evidenced by a 1.67-fold reduction in subchondral bone plate thickness, an 88.57% decrease in OARSI score, a 5.52-fold reduction in MMP13 expression, and a 6.80-fold increase in Col II expression. This novel disease-modifying approach for OA utilizing MNDs-NIR offers insight and a paradigm for improving mitochondrial dysfunction by regulating the accumulation of mitochondrial ROS and ultimately alleviating cellular senescence. Moreover, the dual-pronged therapeutic approach of MNDs-NIR, which addresses both cartilage erosion and subchondral bone lesions in OA, represents a highly promising strategy for managing OA.

Effects of cadmium on the intestinal health of the snail Bradybaena ravida Benson.

The heavy metal cadmium (Cd) is a toxic and bioaccumulative metal that can be enriched in the tissues and organs of living organisms through the digestive tract. However, more research is needed to determine whether food-sourced Cd affects the homeostasis of host gut microflora. In this study, the snail Bradybaena ravida (Benson) was used as a model organism fed with mulberry leaves spiked with different concentrations of Cd (0, 0.052, 0.71, and 1.94 mg kg-1). By combining 16S rRNA high-throughput sequencing with biochemical characterization, it was found that there were increases in the overall microbial diversity and abundances of pathogenic bacteria such as Corynebacterium, Enterococcus, Aeromonas, and Rickettsia in the gut of B. ravida after exposure to Cd. However, the abundances of potential Cd-resistant microbes in the host's gut, including Sphingobacterium, Lactococcus, and Chryseobacterium, decreased with increasing Cd concentrations in the mulberry leaves. In addition, there was a significant reduction in activities of energy, nutrient metabolism, and antioxidant enzymes for gut microbiota of snails treated with high concentrations of Cd compared to those with low ones. These findings highlight the interaction of snail gut microbiota with Cd exposure, indicating the potential role of terrestrial animal gut microbiota in environmental monitoring through rapid recognition and response to environmental pollution.

Induction of phytoextraction, phytoprotection and growth promotion activities in Lupinus albus under mercury abiotic stress conditions by Peribacillus frigoritolerans subsp., mercuritolerans subsp. nov.

Strain SAICEUPBMT was isolated from soils of Almadén (Ciudad Real, Spain), subjected to a high mercury concentration. SAICEUPBMT significantly increased aerial plant weight, aerial plant length and the development of secondary roots under mercury stress; increased twice the absorption of mercury by the plant, while favoring its development in terms of biomass. Similarly, plants inoculated with SAICEUPBMT and grown in soils contaminated with mercury, express a lower activity of antioxidant enzymes; catalase enzymes (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR) for defense against ROS (reactive oxygen species). Whole genome analysis showed that ANI (95. 96 %), dDDH (72.9 %), AAI (93.3 %) and TETRA (0.99) values were on the thresholds established for differentiation a subspecies. The fatty acids analysis related the strain with the Peribacillus frigoritolerans species. And the synapomorphic analysis reveals a common ancestor with analysis related the strain with the Peribacillus frigoritolerans species. Results from genomic analysis together with differences in phenotypic features and chemotaxonomic analysis support the proposal of strain SAICEUPBMT as the type strain of a novel subspecies for which the name Peribacillus frigoritolerans subps. mercuritolerans sp. nov is proposed. The absence of virulence genes and transmissible resistance mechanisms reveals its safety for agronomic uses, under mercury stress conditions. The ability of Peribacillus frigoritolerans subsp. mercuritolerans subsp. nov to improve plant development was tested in a Lupinus albus model, demonstrating a great potential for plant phytoprotection against mercury stress.

Exogenous allyl isothiocyanate mitigates the drought stress by regulating the stomatal characteristic, antioxidant capacity, and glucosinolate metabolism in pakchoi

Drought is a global issue that has increasingly garnered worldwide attention. Glucosinolates (GSLs) are significant sulfur-containing compounds in cruciferous plants such as pakchoi (Brassica rapa L. ssp. chinensis), and their primary biological functions are exerted through their hydrolysis products. Allyl isothiocyanate (AITC), which is one of the degradation products of GSL, plays a crucial role in plants’ response to environmental stresses. To date, the drought-resistant mechanism of AITC has not been fully explored. This study investigated the effects of spraying different concentrations of AITC solutions (1 mM and 10 mM) on the growth parameters, stomatal characteristics, antioxidant indices, and glucosinolate metabolism of pakchoi under drought stress, compared to a control group treated with distilled water. The results shown that under drought stress, AITC spraying enhanced the plant's water retention capacity and restored their growth by promoting stomatal closure and improving photosynthetic capacity in pakchoi; mitigated oxidative stress damage and augmenting the plant's water absorption by increasing the activities of antioxidant enzymes and the concentrations of osmoregulatory substances in pakchoi; the application of AITC restored the glucosinolate metabolism in pakchoi, inhibiting the downregulation of genes associated with GSL synthesis and the upregulation of genes related to degradation that is induced by drought stress, thereby maintaining the balance between GSLs and ITCs.. In conclusion, AITC application alleviated the inhibition of pakchoi growth under drought stress by fostering stomatal closure, bolstering antioxidant defenses, and modulating glucosinolate metabolism.

Transcription factor AtNAC002 positively regulates Cu toxicity tolerance in Arabidopsis thaliana

Copper (Cu) is an essential micronutrient for plant growth and development, but environmental Cu pollution has become increasingly severe, adversely affecting both ecosystems and crop productivity. In this study, we identified the AtNAC002 gene as a positive regulator of Cu toxicity in Arabidopsis thaliana. We found that AtNAC002 expression was induced by Cu excess, and the atnac002 mutant was Cu-sensitive, accumulating more Cu than the wild-type. Additionally, atnac002 mutants exhibit reduced activities of antioxidant enzymes (SOD, POD, and CAT), leading to increased levels of reactive oxygen species and malondialdehyde, which decrease Cu resistance. AtNAC002 might play a role in vacuolar and mitochondrial Cu compartmentalization by regulating genes involved in Cu detoxification, specifically COX11 and HCC1. Furthermore, AtNAC002 was implicated in flavone and flavanol biosynthesis, with the atnac002 mutant showing reduced flavonoid content. Our findings suggest that AtNAC002 is integral to the regulation of Cu toxicity tolerance in A. thaliana. This knowledge is critical for advancing our understanding and offers potential molecular breeding targets to enhance plant performance under Cu excess, which is significant for improving global food security and forest restoration.

Exogenous Methyl Jasmonate Alleviates Mechanical Damage in Banana Fruit by Regulating Membrane Lipid Metabolism

Bananas are economically important fruits, but they are vulnerable to mechanical damage during harvesting and transport. This study examined the effects of methyl jasmonate (MeJA) on the cell membrane integrity and membrane lipid metabolism of wounded banana fruits after harvest. The results showed that 10 and 50 μM MeJA treatments on mechanically wounded bananas significantly delayed ripening and senescence in comparison with the control. At the end of storage, MeJA-treated groups showed a significant reduction in electrolyte leakage and malondialdehyde content, indicating that MeJA protected cell membrane integrity. MeJA also led to a significant decrease in the activity of antioxidant enzymes, including lipoxygenase, diacylglycerol kinase, and lipid phosphate phosphatase. Furthermore, MeJA reduced phospholipase (C and D), phosphatidic acid, and diacylglycerol levels, as well as slowed down the decrease in phosphatidylcholine and phosphatidylinositol contents. Compared to the control, MeJA significantly downregulated the expression of MaPLDγ, MaPLDα, and MaPLDζ. Therefore, MeJA treatment could be a reliable method to delay the senescence of harvested banana fruits subjected to mechanical wounding.

Apigenin With Protective Effect Against Oxidative Injury to Skeletal Muscle Cells via Activation of the Nrf-2HO-1 Pathway

Human skeletal muscle would suffer from an oxidative injury caused by long-term training or exhaustive exercise. It is important to scavenge oxygen free radicals in due course to reduce oxidative damage to human skeletal muscle cells (HSKMC) by some means. Apigenin, as an effective antioxidant, is likely to protect HSKMC against oxidative injury. In this study, tert-butyl hydroperoxide (t-BHP) was used to induce oxidative injured HSKMC. Then, we studied the protective effect of apigenin on cell viability, oxidative stress status, and the expression of antioxidation-related proteins and tried to understand the mechanisms driving these effects. Results show that the cellular viability of HSKMC could be obviously improved by apigenin treatment at the concentration of 80 μM. Pretreatment with celery resulted in the activity of related enzymes approaching normal levels, and decrease the release of malondialdehyde and the level of intracellular reactive oxygen species in HSKMC. The Nuclear factor E2-related factor (Nrf2) signaling pathway could also be activated by apigenin. Therefore, apigenin could attenuate t-BHP induced oxidative injury in HSKMC through enhancement of the activities of related antioxidant enzymes by activating the Nrf2 pathway.

Heating alters the nutritional and antioxidant characteristics of lotus root

To investigate the impact of heating on the nutritional and antioxidant properties of lotus root, a comparative analysis was conducted between its heated and unheated whole powders. The whole powder of heated lotus root (HLRWP) exhibited a higher level of total soluble sugars but a lower level of free phenolic compounds compared to the whole powder of fresh lotus root (FLRWP). Meanwhile, they showed significant differences in metabolite composition encompassing phenolic compounds, flavonoids, amino acids, vitamins and lipids. The replacement of sugar and corn in the medium with 25% HLRWP effectively enhanced the activities of antioxidant enzymes (total superoxide dismutase and catalase), while reducing malonaldehyde content in Drosophila melanogaster males. The average, median and maximum lifespans of the fruit flies were extended by 35.90%, 23.49% and 24.00% respectively, accompanied by an improvement in climbing ability. Additionally, their resistance to oxidative stress induced by hydrogen peroxide or paraquat was enhanced. The antioxidant capacity of HLRWP in vivo was found to be obviously stronger compared to FLRWP, which may have a crucial association with the regulation of L-arginine and adenosine monophosphate levels. The results indicate that heating can enhance the nutritional quality of lotus root products by strengthening their antioxidant capacity.

Muti-omics revealed the mechanisms of MT-conferred tolerance of Elymus nutans Griseb. to low temperature at XiZang

BackgroundLow temperature seriously limited the development of grass and crops in plateau. Thus, it is urgent to develop an effective strategy for improving the plant cold tolerance and elucidate the underlying mechanisms.ResultsWe found that MT alleviated the effects of cold stress on suppressing ENG growth, then improved cold tolerance of ENG. Integration of transcriptome and metabolome profiles showed that both cold exposure (TW) and MT reprogrammed the transcription pattern of galactose and flavonoids biosynthesis, leading to changes in compositions of soluble sugar and flavonoids in ENG. Additionally, TW inhibited the photosynthesis, and destroyed the antioxidant system of ENG, leading to accumulation of oxidant radicals represented by MDA. By contrast, MT promoted activities of antioxidant enzymes and flavonoid accumulation in ENG under cold condition, then reduced the MDA content and maintained normal expression of photosynthesis-related genes in ENG even under TW. Importantly, MT mainly enhanced cold tolerance of ENG via activating zeatin synthesis to regulate flavonoid biosynthesis in vivo. Typically, WRKY11 was identified to regulate MT-associated zeatin synthesis in ENG via directly binding on zeatin3 promoter.ConclusionsMT could enhance ENG tolerance to cold stress via strengthening antioxidant system and especially zeatin synthesis to promote accumulation of flavonoids in ENG. Thus, our research gain insight into the global mechanisms of MT in promoting cold tolerance of ENG, then provided guidance for protecting plant from cold stress in plateau.

Expression and drought functional analysis of one circRNA PecircCDPK from moso bamboo (Phyllostachys edulis).

Drought stress can affect the growth of bamboo. Circle RNAs (CircRNAs) have been found to play a role in drought stress in plants, but their function in moso bamboo is not well understood. In previous studies, we observed that under drought stress, the expression of some circRNAs were altered and predicted to be involved in calcium-dependent protein kinase phosphorylation, as indicated by KEGG enrichment analysis. In this study, we cloned a circRNA called PecircCDPK in moso bamboo that is responsive to drought stress. To further investigate its function, we constructed an overexpression vector using flanking intron sequences supplemented by reverse complementary sequences. When this vector was transferred to Arabidopsis plants, we observed that the roots of the transgenic lines were more developed, the water loss rate decreased, the stomata became smaller, and the activity of antioxidant enzymes increased under drought stress. These findings suggest that overexpression of PecircCDPK can enhance the drought resistance of Arabidopsis thaliana, providing valuable insights for the breeding of moso bamboo with improved resistance to drought.

Identification of the BZR Family in Garlic (Allium sativum L.) and Verification of the AsBZR11 under Salt Stress

Brassinazole-Resistant (BZR) is an important transcription factor (TF) in the brassinosteroid (BR) signaling pathway, which plays a crucial role in plant growth, development and stress resistance. In this study, we performed a genome-wide analysis of BZRs in garlic (Allium sativum L.) and identified a total of 11 members of the AsBZR gene family. By comparing the expression patterns of AsBZR genes under salt stress, the candidate gene AsBZR11 with salt tolerance function was identified. Subcellular localization results showed that AsBZR11 was localized in the nucleus. The salt tolerance of overexpression lines improved, and the germination rate and root length of overexpression lines increased as compared with wild type. The content of reactive oxygen species (ROS) decreased, and the activity of antioxidant enzymes increased in AsBZR11-OE, suggesting that AsBZR11 has the function of improving plant salt tolerance. Our results enriched the knowledge of plant BZR family and laid a foundation for the molecular mechanism of salt tolerance of garlic, which will provide a theoretical basis for the subsequent creation of salt-tolerant germplasm resources.

Exploring the hepatoprotective potential of the probiotic Lactiplantibacillus plantarum E1K2R2 and its exopolysaccharide-postbiotic on ibuprofen-induced acute liver injury in rats.

The present study investigates the hepatoprotective effect of a probiotic Lactiplantibacillus plantarum E1K2R2 and its exopolysaccharide (EPS) against ibuprofen-induced acute liver injury, and to explore the involved underlying mechanisms. Hepatotoxicity was induced by administration of a single dose of ibuprofen (200 mg/kg body weight). The Lpb. plantarum E1K2R2 (109 CFU) and its EPS (200 mg/kg bw) were separately used to feed rats for seven consecutive days before ibuprofen administration. Liver toxicity was assessed by monitoring levels of serum liver enzymes, liver relative weight, oxidative stress and inflammatory markers, and through histopathological analysis. The results showed that ibuprofen administration significantly increased (P < 0.05) liver relative weight, elevated levels of alanine-amino transferase (ALT), aspartate-amino transferase (AST), decreased hepatic gluthatione (GSH) and endogenous antioxidant enzymes including, superoxide dismutase (SOD), catalase (CAT) and increased malondialdehyde (MDA) levels, nitric oxide (NO) and myeloperoxidase (MPO) in hepatic tissues. However, pre-treatment with Lpb. plantarum E1K2R2 and its EPS significantly attenuated these toxicity manifestations. Both pre-treatments restored liver weight, normalized transaminase enzyme levels, enhanced the activity of liver antioxidant enzymes (SOD and CAT), increased GSH content, and significantly reduced NO, MPO and MDA levels (P < 0.05), indicating their protective role against oxidative stress and inflammatory response induced by ibuprofen. Furthermore, histopathological analysis confirmed regular liver morphology in rats pre-treated with the probiotic and its EPS. These findings highlight the potential effectiveness of the probiotic Lpb. plantarum E1K2R2 and its EPS in mitigating ibuprofen-induced liver toxicity.