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PloS One 2024Increases in near-surface ozone (O3) concentrations is a global environmental problem. High-concentration O3 induces stress in plants, which can lead to visible damage... (Meta-Analysis)
Meta-Analysis
Increases in near-surface ozone (O3) concentrations is a global environmental problem. High-concentration O3 induces stress in plants, which can lead to visible damage to plants, reduced photosynthesis, accelerated aging, inhibited growth, and can even plant death. However, its impact has not been comprehensively evaluated because of the response differences between individual plant species, environmental O3 concentration, and duration of O3 stress in plants. We used a meta-analysis approach based on 31 studies 343 observations) to examine the effects of elevated O3 on malondialdehyde (MDA), superoxide dismutase (SOD), and peroxidase (POD) activities in herbaceous plants. Globally, important as they constitute the majority of the world's food crops. We partitioned the variation in effect size found in the meta-analysis according to the presence of plant species (ornamental herb, rice, and wheat), O3 concentration, and duration of O3 stress in plants. Our results showed that the effects of elevated O3 on plant membrane lipid peroxidation depending on plant species, O3 concentration, and duration of O3 stress in plants. The wheat SOD and POD activity was significantly lower compared to the herbs and rice (P<0.01). The SOD activity of all herbaceous plants increased by 34.6%, 10.5%, and 26.3% for exposure times to elevated O3 environments of 1-12, 13-30, and 31-60 days, respectively. When the exposure time was more than 60 days, SOD activity did not increase but significantly decreased by 12.1%. However, the POD activity of herbaceous plants increased by 30.4%, 57.3%, 21.9% and 5.81%, respectively, when exposure time of herbaceous plants in elevated O3 environment was 1-12, 13-30, 31-60 and more than 60 days. Our meta-analysis revealed that (1) rice is more resistant to elevated O3 than wheat and ornamental herbs likely because of the higher activity of antioxidant components (e.g., POD) in the symplasts, (2) exposure to elevated O3 concentrations for >60 days, may result in antioxidant SOD lose its regulatory ability, and the antioxidant component POD in the symplast is mainly used to resist O3 damage, and (3) the important factors affected the activity of SOD and POD in plants were not consistent: the duration of O3 stress in plants was more important than plant species and O3 concentration for SOD activity. However, for POD activity, plant species was the most important factor.
Topics: Superoxide Dismutase; Antioxidants; Ozone; Malondialdehyde; Lipid Peroxidation; Plants; Oxidative Stress; Oxidoreductases; Oryza; Peroxidase
PubMed: 38917096
DOI: 10.1371/journal.pone.0305688 -
Frontiers in Plant Science 2024The tolerance to salinity stress is an intricate phenomenon at cellular and whole plant level that requires the knowledge of contributing physiological and biochemical...
The tolerance to salinity stress is an intricate phenomenon at cellular and whole plant level that requires the knowledge of contributing physiological and biochemical processes and the genetic control of participating traits. In this context, present study was conducted with objective to evaluate the physiological, biochemical, and genetic responses of different wheat genotypes including bread wheat (BW) and synthetic hexaploids (SHs) under saline and control environment. The experiment was conducted in two factorial arrangement in randomized complete block design (RCBD), with genotypes as one factor and treatments as another factor. A significant decline in physiological traits (chlorophyll, photosynthesis, stomatal conductance, transpiration, and cell membrane stability) was observed in all genotypes due to salt stress; however, this decline was higher in BW genotypes as compared to four SH genotypes. In addition, the biochemical traits including enzymes [superoxide dismutase, catalase, and peroxidase (POD)] activity, proline, and glycine betaine (GB) illustrated significant increase along with increase in the expression of corresponding genes (, , , , and ) due to salt stress in SHs as compared to BW. Correspondingly, highly overexpressed genes, , , and caused a significant decline in Na/K in SH as compared to BW genotypes under salt stress. Moreover, correlation analysis, principal component analysis (PCA), and heatmap analysis have further confirmed that the association and expression of physiological and biochemical traits varied significantly with salinity stress and type of genotype. Overall, the physiological, biochemical, and genetic evaluation proved SHs as the most useful stock for transferring salinity tolerance to other superior BW cultivars via the right breeding program.
PubMed: 38916034
DOI: 10.3389/fpls.2024.1336571 -
Frontiers in Plant Science 2024Rapid industrialization and urbanization have caused severe soil contamination with cadmium (Cd) necessitating effective remediation strategies. Phytoremediation is a...
Rapid industrialization and urbanization have caused severe soil contamination with cadmium (Cd) necessitating effective remediation strategies. Phytoremediation is a widely adopted technology for remediating Cd-contaminated soil. Previous studies have shown that has a high Cd accumulation capacity and tolerance indicating its potential for Cd soil remediation. However, the mechanisms underlying its response to Cd stress remain unclear. In this study, physiological, transcriptomic, and metabolomic analyses were conducted to explore the response of roots to Cd stress at different time points. The results revealed that Cd stress significantly increased malondialdehyde (MDA) levels in , which simultaneously activated its antioxidant defense system, enhancing the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) by 19.73%-50%, 22.87%-38.89%, and 32.31%-45.40% at 12 h, 36 h, 72 h, and 7 days, respectively, compared with those in the control (CK). Moreover, transcriptomic and metabolomic analyses revealed 245, 5,708, 9,834, and 2,323 differentially expressed genes (DEGs), along with 66, 62, 156, and 90 differentially expressed metabolites (DEMs) at 12 h, 36 h, 72 h, and 7 days, respectively. Through weighted gene coexpression network analysis (WGCNA) of physiological indicators and transcript expression, eight hub genes involved in phenylpropanoid biosynthesis, signal transduction, and metal transport were identified. In addition, integrative analyses of metabolomic and transcriptomic data highlighted the activation of lipid metabolism and phenylpropanoid biosynthesis pathways under Cd stress suggesting that these pathways play crucial roles in the detoxification process and in enhancing Cd tolerance in . This comprehensive study provides detailed insights into the response mechanisms of to Cd toxicity.
PubMed: 38916029
DOI: 10.3389/fpls.2024.1389207 -
BioRxiv : the Preprint Server For... Jun 2024Diffuse midline gliomas (DMGs) are lethal primary brain tumors in children. The imipridones ONC201 and ONC206 induce mitochondrial dysfunction and have emerged as...
UNLABELLED
Diffuse midline gliomas (DMGs) are lethal primary brain tumors in children. The imipridones ONC201 and ONC206 induce mitochondrial dysfunction and have emerged as promising therapies for DMG patients. However, efficacy as monotherapy is limited, identifying a need for strategies that enhance response. Another hurdle is the lack of biomarkers that report on drug-target engagement at an early timepoint after treatment onset. Here, using H-magnetic resonance spectroscopy, which is a non-invasive method of quantifying metabolite pool sizes, we show that accumulation of ψ-aminobutyric acid (GABA) is an early metabolic biomarker that can be detected within a week of ONC206 treatment, when anatomical alterations are absent, in mice bearing orthotopic xenografts. Mechanistically, imipridones activate the mitochondrial protease ClpP and upregulate the stress-responsive transcription factor ATF4. ATF4, in turn, upregulates glutamate decarboxylase, which synthesizes GABA, and downregulates , which degrades GABA, leading to GABA accumulation in DMG cells and tumors. Functionally, GABA secreted by imipridone-treated cells acts in an autocrine manner via the GABAB receptor to induce expression of superoxide dismutase (SOD1), which mitigates imipridone-induced oxidative stress and, thereby, curbs apoptosis. Importantly, blocking autocrine GABA signaling using the clinical stage GABAB receptor antagonist SGS-742 exacerbates oxidative stress and synergistically induces apoptosis in combination with imipridones in DMG cells and orthotopic tumor xenografts. Collectively, we identify GABA as a unique metabolic adaptation to imipridones that can be leveraged for non-invasive assessment of drug-target engagement and therapy. Clinical translation of our studies has the potential to enable precision metabolic therapy and imaging for DMG patients.
ONE SENTENCE SUMMARY
Imipridones induce GABA accumulation in diffuse midline gliomas, an effect that can be leveraged for therapy and non-invasive imaging.
PubMed: 38915617
DOI: 10.1101/2024.06.07.597982 -
Scientific Reports Jun 2024Flavonoids are crucial secondary metabolites that possess the ability to mitigate UV damage and withstand both biotic and abiotic stresses. Therefore, it is of immense...
Flavonoids are crucial secondary metabolites that possess the ability to mitigate UV damage and withstand both biotic and abiotic stresses. Therefore, it is of immense significance to investigate the flavonoid content as a pivotal indicator for a comprehensive assessment of chestnut's drought tolerance. This study aimed to determine the flavonoid content and drought tolerance-related physiological and biochemical indices of six chestnut varieties (clones) grafted trees-Qianxi 42 (QX42), Qinglong 45 (QL45), Yanshanzaofeng (YSZF), Yanzi (YZ), Yanqiu (YQ), and Yanlong (YL)-under natural drought stress. The results were used to comprehensively analyze the drought tolerance ability of these varieties. The study revealed that the ranking of drought tolerance indices in terms of their ability to reflect drought tolerance was as follows: superoxide (oxide) dismutase (SOD) activity, ascorbate peroxidase (APX) activity, flavone content, catalase (CAT) activity, proline (PRO) content, soluble sugar content, peroxidase (POD) activity, betaine content, flavonol content, hydrogen peroxide (HO) content, soluble protein content, superoxide ion (OFR) content, superoxide (ion OFR) production rate, malondialdehyde (MDA) content, chlorophyll content. Through principal component analysis, the contents of flavonoids and flavonols can be used as indicators for comprehensive evaluation of drought tolerance of chestnut. The comprehensive evaluation order of drought tolerance of grafted trees of 6 chestnut varieties (Clones) was: QL45 > QX42 > YQ > YZ > YSZF > YL.
Topics: Flavonoids; Droughts; Stress, Physiological; Malondialdehyde; Superoxide Dismutase; Proline; Chlorophyll; Hydrogen Peroxide; Fagaceae; Adaptation, Physiological; Catalase; Ascorbate Peroxidases; Drought Resistance; East Asian People
PubMed: 38914646
DOI: 10.1038/s41598-024-65479-2 -
Scientific Reports Jun 2024Rose flowers (Rosa hybrida L.) are highly perishable and have a limited vase life. This study evaluated the effects of preharvest foliar applications of γ-aminobutyric...
Rose flowers (Rosa hybrida L.) are highly perishable and have a limited vase life. This study evaluated the effects of preharvest foliar applications of γ-aminobutyric acid (GABA) and calcium chloride (CaCl), individually and combined, on antioxidant responses and vase life of cut Jumilia rose flowers. Treatments included foliar sprays of GABA at 0, 20, 40, and 60 mM and CaCl at 0, 0.75%, and 1.5%, applied in a factorial design within a completely randomized setup before harvest. Results showed GABA and CaCl interaction (especially, 60 mM GABA and 1.5% CaCl) significantly increased enzymatic antioxidants including superoxide dismutase, catalase, and peroxidase, as well as non-enzymatic antioxidants such as flavonoids, carotenoids, phenolics, and antioxidant activity in petals compared to control. SOD activity in roses, treated with CaCl (1.5%) and GABA (60 mM), peaked at 7.86 units. mg protein min, showing a nearly 2.93-fold increase over the control (2.68 units. mg protein min). A parallel trend was observed for CAT activity. These treatments also reduced petal malondialdehyde content and polyphenol oxidase activity. Protein content and vase life duration increased in all treatments. Plants treated with a combination of GABA (20 mM) and CaCl (0.75%), GABA (60 mM) and CaCl (1.5%), or GABA (40 mM) individually exhibited the longest vase life duration. The co-application of GABA and CaCl improved the antioxidant activity and postharvest quality of cut roses by reducing PPO activity and MDA contents, increasing protein content and prolonging vase life. This treatment is a potential postharvest strategy to improve antioxidant capacity and delay senescence in cut roses.
Topics: Flowers; Calcium Chloride; Antioxidants; gamma-Aminobutyric Acid; Rosa; Superoxide Dismutase; Catalase; Malondialdehyde; Plant Leaves
PubMed: 38914640
DOI: 10.1038/s41598-024-64021-8 -
Frontiers in Chemistry 2024The oxalic acid complexation method and sulfuric acid heat treatment method were used to synthesize the YMnO (YMO) and YMO-SO (YMO-SO) photocatalysts. The YMO-SO...
Synthesis and full-spectrum-responsive photocatalytic activity from UV/Vis to near-infrared region of S-O decorated YMnO nanoparticles for photocatalytic degradation of ibuprofen.
The oxalic acid complexation method and sulfuric acid heat treatment method were used to synthesize the YMnO (YMO) and YMO-SO (YMO-SO) photocatalysts. The YMO-SO photocatalyst maintained the crystal structure of YMO, but the particle size increased slightly and the optical band gap decreased significantly. The YMO-SO photocatalyst demonstrates a wide range of light absorption capabilities, covering ultraviolet, visible and near-infrared light. The photocatalytic activity of YMO-SO was investigated with ibuprofen as the target pollutant. The YMO-SO photocatalyst exhibits high ultraviolet (UV), visible and near-infrared photocatalytic activity. Experiments with different environmental parameters confirmed that the best catalyst content was 1 g/L, the best drug concentration was 75 mg/L and the best pH value was 7. The capture experiment, free radical detection experiment and photocatalytic mechanism analysis confirmed that the main active species of YMO-SO photocatalyst were hole and superoxide free radical.
PubMed: 38911994
DOI: 10.3389/fchem.2024.1424548 -
Frontiers in Plant Science 2024Manganese (Mn) plays a pivotal role in plant growth and development. Aside aiding in plant growth and development, Mn as heavy metal (HM) can be toxic in soil when...
Metabolomics and physio-chemical analyses of mulberry plants leaves response to manganese deficiency and toxicity reveal key metabolites and their pathways in manganese tolerance.
INTRODUCTION
Manganese (Mn) plays a pivotal role in plant growth and development. Aside aiding in plant growth and development, Mn as heavy metal (HM) can be toxic in soil when applied in excess. is an economically significant plant, capable of adapting to a range of environmental conditions and possessing the potential for phytoremediation of contaminated soil by HMs. The mechanism by which tolerates Mn stresses remains obscure.
METHODS
In this study, Mn concentrations comprising sufficiency (0.15 mM), higher regimes (1.5 mM and 3 mM), and deficiency (0 mM and 0.03 mM), were applied to in pot treatment for 21 days to understand Mn tolerance. Mn stress effects on the net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), intercellular CO concentration (Ci), chlorophyll content, plant morphological traits, enzymatic and non-enzymatic parameters were analyzed as well as metabolome signatures via non-targeted LC-MS technique.
RESULTS
Mn deficiency and toxicity decrease plant biomass, Pn, Ci, Gs, Tr, and chlorophyll content. Mn stresses induced a decline in the activities of catalase (CAT) and superoxide dismutase (SOD), while peroxidase (POD) activity, and leaf Mn content, increased. Soluble sugars, soluble proteins, malondialdehyde (MDA) and proline exhibited an elevation in Mn deficiency and toxicity concentrations. Metabolomic analysis indicates that Mn concentrations induced 1031 differentially expressed metabolites (DEMs), particularly amino acids, lipids, carbohydrates, benzene and derivatives and secondary metabolites. The DEMs are significantly enriched in alpha-linolenic acid metabolism, biosynthesis of unsaturated fatty acids, galactose metabolism, pantothenate and CoA biosynthesis, pentose phosphate pathway, carbon metabolism, etc.
DISCUSSION AND CONCLUSION
The upregulation of Galactinol, Myo-inositol, Jasmonic acid, L-aspartic acid, Coproporphyrin I, Trigonelline, Pantothenol, and Pantothenate and their significance in the metabolic pathways makes them Mn stress tolerance metabolites in . Our findings reveal the fundamental understanding of DEMs in 's response to Mn nutrition and the metabolic mechanisms involved, which may hold potential significance for the advancement of genetic improvement initiatives and phytoremediation programs.
PubMed: 38911982
DOI: 10.3389/fpls.2024.1349456 -
Frontiers in Plant Science 2024Human activities have increased nitrogen (N) and phosphorus (P) inputs to the Yellow River Delta and the supply level of N and P affects plant growth as well as...
Human activities have increased nitrogen (N) and phosphorus (P) inputs to the Yellow River Delta and the supply level of N and P affects plant growth as well as ecosystem structure and function directly. However, the root growth, stoichiometry, and antioxidant system of plants in response to N and P additions, especially for herbaceous halophyte in the Yellow River Delta (YRD), remain unknown. A field experiment with N addition (0, 5, 15, and 45 g N m yr, respectively) as the main plot, and P addition (0 and 1 g N m yr, respectively) as the subplot, was carried out with a split-plot design to investigate the effects on the root morphology, stoichiometry, and antioxidant system of . The results showed that N addition significantly increased the above-ground and root biomass as well as shoot-root ratio of , which had a significant interaction with P addition. The highest biomass was found in the treatment with 45 g N m yr combined with P addition. N addition significantly increased TN content and decreased C:N ratio of root, while P addition significantly increased TP content and decreased C:P ratio. The main root length (MRL), total root length (TRL), specific root length (SRL), and root tissue density (RTD) of root were significantly affected by N addition and P addition, as well as their interaction. The treatments with or without P addition at the 45 g N m yr of N addition significantly increased the superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) activities and soluble protein content of roots, decreased malondialdehyde (MDA) content. And there was a significant interaction between the N and P addition on SOD activity. Therefore, N and P additions could improve the growth of by altering the root morphology, increasing the root nutrient content, and stimulating antioxidant system.
PubMed: 38911979
DOI: 10.3389/fpls.2024.1410036 -
Open Life Sciences 2024A pot experiment was conducted to investigate the combined effects of different nitrogen fertilizer levels (5, 25, and 45 kg of pure nitrogen per 667 m²) and...
A pot experiment was conducted to investigate the combined effects of different nitrogen fertilizer levels (5, 25, and 45 kg of pure nitrogen per 667 m²) and biochar concentrations (0, 0.7, 1.4, and 2.1%) on the growth, yield, and fruit quality of pepper. The findings indicated that a combination of 25 kg/667 m of nitrogen and either 0.7% or 1.4% biochar significantly enhanced plant growth, yield, and fruit quality. Specifically, the N2 treatment (25 kg of pure nitrogen per 667 m²) increased substrate porosity, alkali-hydrolyzed nitrogen content, and available phosphorus content. It also boosted root activity and superoxide dismutase activity in pepper leaves, resulting in increased yield and better fruit quality. Furthermore, the proper addition of biochar (0.7-1.4% by weight) enhanced the physical and chemical properties of the substrate, including increased chlorophyll content and enzyme activity in plants, thereby leading to improved overall plant growth, yield, and fruit quality.
PubMed: 38911928
DOI: 10.1515/biol-2022-0882