Search Results (11,748)

Cadmium (Cd), a pervasive and highly phytotoxic metal pollutant, poses severe threats to agricultural productivity, ecosystem stability, and human health through its entry into the food chain. Plants have evolved intricate defense mechanisms, among which the strategic manipulation of nutrient elements emerges as a critical physiological and biochemical strategy for mitigating Cd stress. This comprehensive review delves deeply into the multifaceted roles of essential macronutrient elements (nitrogen, phosphorus, potassium, calcium, magnesium, sulfur), essential micronutrient elements (zinc, iron, manganese, copper) and non-essential beneficial elements (silicon, selenium) in modulating plant responses to Cd toxicity. We meticulously dissect the physiological, biochemical, and molecular underpinnings of how these nutrients influence Cd bioavailability in the rhizosphere, Cd uptake and translocation pathways, sequestration and compartmentalization within plant tissues, and the activation of antioxidant defense systems. Nutrient elements exert their influence through diverse mechanisms: competing with Cd for root uptake transporters, promoting the synthesis of complexes that reduce Cd mobility, stabilizing cell walls and plasma membranes to restrict apoplastic flow and symplastic influx, modulating redox homeostasis by enhancing antioxidant enzyme activities and non-enzymatic antioxidant pools, regulating signal transduction pathways, and influencing gene expression profiles related to metal transport, chelation, and detoxification. The complex interactions between nutrients themselves further shape the plant’s capacity to withstand Cd stress. Recent advances elucidating nutrient-mediated epigenetic regulation, microRNA involvement, and the role of nutrient-sensing signaling hubs in Cd responses are critically evaluated. Furthermore, we synthesize the practical implications of nutrient management strategies, including optimized fertilization regimes, selection of nutrient-efficient genotypes, and utilization of nutrient-enriched amendments, for enhancing phytoremediation efficiency and developing low-Cd-accumulating crops, thereby contributing to safer food production and environmental restoration in Cd-contaminated soils. The intricate interplay between plant nutritional status and Cd stress resilience underscores the necessity for a holistic, nutrient-centric approach in managing Cd toxicity in agroecosystems. Full article

Lysolecithin, characterized by its superior emulsifying and stabilizing properties, facilitates nutrient absorption and is extensively utilized in aquatic feed formulation. Nevertheless, its precise function in shrimp nutrition and physiology remains inadequately understood. This study aimed to evaluate the feasibility and optimal dosage of replacing 2% soybean lecithin with varying levels of soybean lysolecithin (0–2%) in the diet of Litopenaeus vannamei. Growth performance, antioxidant indices, and lipid metabolism were assessed. The results demonstrated that dietary supplementation with 0.1% lysolecithin had the best growth performance, significantly improved lipid retention and apparent crude fat digestibility, while reducing malondialdehyde (MDA) levels in the hepatopancreas and alleviating endoplasmic reticulum (ER) stress. The 0.1% group also exhibited better hepatopancreatic tissue structure and lipid metabolic homeostasis. In contrast, higher inclusion levels (≥1.5%) led to increased lipid accumulation and enhanced activities of lipid metabolic enzymes but were associated with a risk of oxidative stress and less favorable tissue morphology. No significant differences in antioxidant enzyme activities were observed among groups. It is hypothesized that lysolecithin may regulate lipid metabolism and homeostasis via the Ca²⁺/CaMKKβ/AMPK signaling pathway; further studies are required to confirm this mechanism. In conclusion, 0.1% soybean lysolecithin is recommended as the optimal dietary level for L. vannamei, supporting its feasibility as a substitute for 2% soybean lecithin in shrimp feed. Full article

Conventional plant disease management primarily depends on chemical pesticides. However, with the rising concerns related to human health, environmental sustainability, and the emergence of resistant pathogens, biocontrol agents (BCAs) have gained more attention as eco-friendly alternatives. Among the potential biocontrol agents, yeasts stand out due to their safety, adaptability, and diverse antagonistic mechanisms, ranging from competition and enzyme secretion to volatile compound production and immunity induction. Despite their potential, yeast-based BCAs face limitations in field efficacy, regulation, and an incomplete understanding of their molecular interactions. Most current studies focus on simple, pairwise interactions, overlooking the complexity of agroecosystems, where plants, pathogens, and BCAs interact within broader microbial communities. This review addresses the importance of understanding tripartite interactions among plants, pathogens, and yeasts, supported by integrated transcriptomic and comparative genomic approaches, as well as meticulous observations of phenotypic expressions to uncover strain-specific defense mechanisms and mode of action. By referring to well-studied models like Blumeria graminis f.sp. hordei–Hordeum vulgare–Pseudozyma flocculosa and Trichoderma tripartite systems, we highlight the underexplored potential of yeasts to modulate plant immunity and influence pathogen behavior through complex molecular crosstalk. Bridging these knowledge gaps through integrating proteomic, metabolomic, and transcriptomic analyses, we can better harness yeasts in sustainable and targeted biocontrol strategies. Full article

Lead (Pb) in soil poses serious environmental and health risks, and its removal requires complex and costly treatment methods to meet strict regulatory standards. To effectively address this challenge, innovative and efficient techniques are essential. Sepiolite-supported MnFe₂O₄ (MnFe₂O₄/SEP) composites were synthesized via a chemical co-precipitation method. The effects of MnFe₂O₄/SEP on soil pH, cation exchange capacity (CEC), available Pb content, Pb²⁺ uptake, and the activities of antioxidant enzymes in Brassica chinensis (Pak Choi) were examined. MnFe₂O₄/SEP showed superior Pb²⁺ adsorption compared to SEP alone, fitting Langmuir models, Dubinin-Radushkevich (D-R) models, Temkin models and pseudo-second-order kinetics. The maximum adsorption capacities at 298, 308, and 318 K were 459, 500 and 549 mg·g⁻¹, respectively. XPS analysis indicated that chemisorption achieved through ion exchange between Pb²⁺ and H⁺ was the main mechanism. MnFe₂O₄/SEP increased the soil pH by 0.2–1.5 units and CEC by 18–47%, while reducing available Pb by 12–83%. After treatment with MnFe₂O₄/SEP, acid-extractable and reducible Pb in the soil decreased by 14% and 39%, while oxidizable and residual Pb increased by 26% and 21%, respectively. In Brassica chinensis, MnFe₂O₄/SEP reduced Pb²⁺ uptake by 76%, increased chlorophyll content by 36%, and decreased malondialdehyde (MDA) levels by 36%. The activities of antioxidant enzymes—superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT)—were decreased by 29%, 38% and 17%, respectively. These findings demonstrate that MnFe₂O₄/SEP is an efficient Pb²⁺ adsorbent that immobilizes Pb in soil mainly through ion exchange, thereby providing a highly effective strategy for remediating Pb-contaminated soils and improving plant health. Full article

The immune system is crucial in protecting against disease, but it can also contribute to chronic illnesses when it malfunctions, with different conditions involving either inflammation or immune suppression. Current treatments often fall short due to limited effectiveness and side effects. Nanomedicine, particularly cerium oxide nanoparticles (nanoceria), offers promising potential due to its unique therapeutic properties and role in modulating macrophages. Nanoceria (<5 nm) possess the catalytic ability to mimic natural enzymes such as superoxide dismutase, peroxidase, and catalase, enabling effective scavenging of reactive oxygen species (ROS), which play a central role in the pathogenesis of chronic inflammation and cancer. This review comprehensively summarizes the current advances in the application of nanoceria for inflammatory and anti-inflammatory therapy, including their modulatory effects on immune cell activation, cytokine production, and resolution of inflammatory responses. We discuss the mechanisms underlying their immunomodulatory actions in various disease contexts, such as rheumatoid arthritis, women’s health conditions (e.g., endometriosis), wound healing, and cancer. Additionally, the review highlights biocompatibility, therapeutic efficacy, adaptability in imaging (theranostics), and challenges in translating nanoceria-based therapies into clinical practice. The multifunctionality of nanoceria positions them as innovative candidates for next-generation immunotherapy aimed at efficiently controlling inflammation and promoting tissue repair. Full article

The present study aimed to identify genes encoding enzymes involved in the biotransformation of monoterpenoid (–)-isopulegol by Rhodococcus rhodochrous IEGM 1362. This strain is able to transform (–)-isopulegol with formation of two novel metabolites with promising antitumor and analeptic activities. Cell fractions of rhodococci and specific inhibitor of cytochrome P450-dependent oxygenase activity were used to establish the localization and type of biotransformation enzymes. The expression of nine CYP450 genes selected by bioinformatics analysis was analyzed by quantitative real-time PCR (qRT-PCR). Selection of optimal reference genes for normalization of qRT-PCR results was performed using BestKeeper, Normfinder, geNorm, Delta CT, and RefFinder algorithms. As a result of these studies, the role of CYP450 enzyme complexes in the biotransformation of (–)-isopulegol was confirmed, and their cytoplasmic localization was established. The genes encoding DNA gyrase subunit B (gyrB) and protein translocase subunit A (secA) were selected as the most stable reference genes. The induced expression of the gene encoding CYP450 hydroxylase in the presence of (–)-isopulegol was determined. The obtained data allow us to identify the specific CYP450 enzyme involved in (–)-isopulegol biotransformation by R. rhodochrous IEGM 1362 and lay the foundation for further studies of molecular and genetic mechanisms of monoterpenoid biotransformation. Full article

The glyoxalase pathway intermediate S-d-lactoylglutathione was recently implicated in protein post-translational modifications in animal systems. Here, we examined the spontaneous modification of the Arabidopsis thaliana cytosolic glyceraldehyde-3-phosphate dehydrogenase C1 (GAPC1) by this compound. Incubation of GAPC1 with S-d-lactoylglutathione resulted in the inhibition of enzyme activity. The inhibitory effect was concentration dependent and increased at alkaline pHs. Furthermore, the inhibition of GAPC1 by S-d-lactoylglutathione was favored by oxidative conditions and reversed by reduction with dithiothreitol. Analyses of the S-d-lactoylglutathione-treated protein by nanoLC-MS/MS revealed S-glutathionylation of its two Cys residues and N-lactoylation of six Lys residues. Protein structure predictions showed that the double S-glutathionylation is accommodated by the GAPC1 catalytic pocket, which likely explains enzyme inhibition. N-lactoylated sites overlap partially with previously reported N-acetylated sites at the surface of the GAPC1 tetramer. The efficiency of cytosolic glutaredoxin and thioredoxin isoforms was tested for reversing the S-d-lactoylglutathione-induced modification. In these assays, recovery of GAPC1 activity after inhibition by S-d-lactoylglutathione treatment was used as indicator of efficiency. The results show that both types of redoxins were able to reverse inhibition. We propose a model describing the mechanisms involved in the two types of post-translational modifications found on GAPC1 following exposure to S-d-lactoylglutathione. The possible involvement of these findings for the control over glycolytic metabolism is discussed. Full article

Increased hepatic triacylglycerol (TG) storage in lipid droplets (LDs) is a hallmark of metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH). Human carboxylesterase 1 (CES1) regulates TG storage and secretion in hepatocytes, but the mechanism remains to be elucidated. We performed studies in rat hepatoma McArdle RH7777 cells stably transfected with CES1 cDNA and in Ces1d-deficient mice using a variety of biochemical, pharmacological and cell biology approaches including the assessment of gene expression, confocal immunofluorescence microscopy, lipid synthesis measurements and quantitative mass spectrometry. CES1-expressing cells accrued more TG compared to cells lacking CES1 when incubated with oleic acid. CES1 increased the expression of Srebf1c, Nr1h3 and Nr1h2 encoding transcription factors (SREBP1c and LXRα and LXRβ, respectively) that regulate the expression of lipogenic genes. Additionally, CES1 increased the expression of Acsl1 encoding an enzyme catalyzing fatty acid activation and the expression of Dgat1 and Dgat2 encoding enzymes catalyzing TG synthesis. Treatment of CES1-expressing cells with PPARγ antagonist (GW9662), LXR antagonist (GSK2033) or CYP27A1 inhibitor Felodipine prevented CES1-mediated fatty acid esterification into TG. Ces1d-deficient mice fed high-fat diet (HFD) presented with decreased expression of Nr1h3, Nr1h2, Srebf1c and reduced hepatic TG content. Felodipine and GSK2033 treatment eliminated the differential effects on TG concentration between wild-type and Ces1d-deficient hepatocytes. The results suggest that CES1/Ces1d activates PPARγ, LXR and SREBP1c pathways, thereby increasing TG synthesis and LD storage by augmenting fatty acid esterification. Full article

Dendrobium officinale (Orchidaceae) is a commonly used medicinal and edible herb. Although its anti-ageing properties have been demonstrated, the underlying mechanisms remain unclear. We employed network pharmacology and molecular biology techniques to systematically explore its anti-ageing mechanisms. An ageing model was established using D-galactose-induced Kunming mice. D. officinale significantly ameliorated ageing-related symptoms, including behavioural impairment and organ index reduction. It enhanced antioxidant capacity by increasing serum T-AOC levels and restoring renal activities of key antioxidant enzymes (SOD, GSH-Px, CAT) while reducing MDA; it suppressed serum TNF-α levels, indicating anti-inflammatory effects. Histopathological examination revealed that D. officinale alleviated D-galactose-induced renal damage, including tubular cell swelling and glomerular capsule widening. Network pharmacology identified 8 core active compounds (e.g., 5,7-dihydroxyflavone, naringenin) and 10 key targets (e.g., HSP90AA1, EGFR, MAPK3). KEGG analysis highlighted pathways including neuroactive ligand–receptor interaction, cAMP signalling, and calcium signalling. Molecular docking confirmed strong binding affinities between core compounds and key targets. Western blotting and immunohistochemistry validated that D. officinale upregulated EGFR, HSP90AA1, ERK, and GAPDH expression in renal tissues. In summary, D. officinale exerts anti-ageing effects by modulating oxidative stress, suppressing inflammation, and regulating multiple signalling pathways. Our findings provide a scientific rationale for its application in anti-ageing interventions. Full article

High temperature stress is a critical factor affecting the growth and yield of melons (Cucumis melo L.), and improving heat tolerance is therefore crucial for stable production. While the overexpression of the CmDUF239-1 gene is known to improve salt tolerance in melons, its impact on heat tolerance remains unexplored. The role of the CmDUF239-1 gene in enhancing heat tolerance and its underlying mechanisms was investigated in this study. Melon seedlings overexpressing CmDUF239-1 (OEDUF239-1), generated via root transformation, exhibited significantly lower reductions in fresh and dry mass under heat stress compared to controls, indicating enhanced heat tolerance. One day post-stress, antioxidant enzyme activities (SOD, POD, CAT, APX, and GR) increased significantly in OEDUF239-1, while malondialdehyde (MDA) levels decreased. Additionally, proline content and the activity of its synthesizing enzyme (P5CS) rose, whereas the activity of proline dehydrogenase (ProDH) dropped. Transcriptomic and qPCR analyses revealed that CmDUF239-1 overexpression upregulated antioxidant enzyme-related genes (e.g., CmCSD1, CmPOD1) and proline-related genes (e.g., CmP5CS), as well as Heat Shock Protein (HSP) genes (e.g., CmHSP17.6II, CmHSP18.2). In summary, the enhancement of heat tolerance in melon by the CmDUF239-1 gene was mediated through the upregulation of genes involved in antioxidant defense and proline metabolism, together with increased accumulation of HSPs, providing a mechanistic basis for heat-resilient breeding programs. Full article

In the context of contemporary climate change, drought is widely recognized as a major stressor affecting plant growth. While numerous studies have demonstrated that Serendipita indica enhances stress resistance in host plants and is widely used in agriculture, research on its symbiotic interactions with woody plants for improving drought tolerance remains limited. This study investigated the effects of S. indica inoculation on the growth of Phoebe sheareri seedlings under varying drought conditions—well-watered (WW), moderate drought (MD), and severe drought (SD)—and explored the physiological mechanisms underlying improved drought resistance. The results showed that under WW conditions, S. indica inoculation promoted seedling growth and development. Under MD and SD conditions, although drought stress inhibited growth, inoculation significantly increased plant biomass, root parameters, chlorophyll content, and photosynthetic efficiency. Additionally, it alleviated drought-induced damage by reducing REC, MDA, H₂O₂, and O₂⁻ levels, while enhancing SOD, POD, and CAT activities, and increasing root ABA, GA, IAA, and CTK content. Under MD stress, adaptive changes in root architecture and hormone levels were observed, including increases in total root length, surface area, volume, average diameter, and elevated IAA and CTK levels—all of which were further enhanced by S. indica inoculation. In conclusion, symbiosis with S. indica improved drought tolerance in P. sheareri seedlings likely through enhanced photosynthesis, antioxidant enzyme activity, and hormone regulation. Full article

Citrus creasing is a physiological rind disorder. Satsuma mandarin (Citrus unshiu Marc.) is the most widely cultivated mandarin variety worldwide and exhibits a high susceptibility to creasing. To investigate the physiological mechanisms underlying creasing, satsuma mandarin trees were treated with different drought stress during fruit expansion, then the relationship between the soil water content and creasing incidence was analyzed, while also examining the rind morphology, oil gland distribution in the flavedo, antioxidant enzyme activities, hormone concentrations, cell wall components, mineral content of creasing fruit, and the impact of creasing on fruit quality. Results showed that severe water stress (35% SRWC) increased the creasing incidence rate by 28% compared to well-irrigated treatments (80% SRWC). The creasing fruit oil gland diameter reduced by 35.7% and the density increased by 149.7% compared to healthy fruits. Simultaneously, the content of H₂O₂ and proline elevated by 47.1% and 8.3% respectively, and the activities of SOD, POD, and CAT of the creasing rind were enhanced significantly. Additionally, the content of IAA, ZR, and MeJA decreased by 17.2%, 7.8%, and 50.2%, respectively. Cell wall components such as cellulose, hemicellulose, and protopectin content reduced by 44.6%, 31.7%, and 33.1%, while soluble pectin increased by 36.3%. Significant alterations were observed in several minerals (Al, Fe, Na, Ni, V, Ga, Zn, Ba, Sn, Hg, Sc, Y, and La). However, fruit quality remained unaffected by creasing. These results demonstrate that drought is a key factor inducing creasing. Increased oil gland density, the degradation of cell wall components, elevated oxidative stress, reductions in phytohormones, and altered mineral element content work together to contribute to rind cells’ structural instability and lead to creasing in the satsuma mandarin. Full article

Polyethylene microplastics (PE-MPs) and glyphosate (GLY) are widespread aquatic contaminants, but their combined effects on microalgae remain poorly understood. This study assessed the individual and joint toxicity of GLY and PE-MPs to the model microalga Chlorella vulgaris. Acute (3-day) and chronic (7-day) exposures were performed using GLY at 1–40 mg/L, alone or combined with PE-MPs (10 mg/L). A four-parameter log-logistic (4PL) model was applied to estimate median effect concentrations (EC₅₀). After 72 h, the EC₅₀ values were 9.77 mg/L for the GLY single system and 2.31 mg/L for the GLY-PE combined system, confirming enhanced toxicity in combined exposures. Co-exposure reduced pigment levels (chlorophyll a, chlorophyll b, and carotenoids) by up to 65% and significantly increased oxidative stress markers, including reactive oxygen species production and malondialdehyde accumulation, compared with single treatments. Antioxidant enzymes (superoxide dismutase and catalase) showed concentration- and time-dependent responses, indicating activation of cellular defense mechanisms. Scanning Electron Microscopy revealed PE-induced aggregation and structural damage to algal cells, particularly at higher GLY concentrations. These findings demonstrate that PE-MPs can amplify the toxic effects of GLY on microalgae and highlight the need for further studies at environmentally relevant concentrations and with different polymer types. Full article

Light-dependent protochlorophyllide oxidoreductase (LPOR, E.C.1.3.1.33) plays a crucial role in the biosynthesis of chlorophyll in plants. Therefore, inactivating LPOR can hinder the production of chlorophyll to achieve the effect of weed control. In this research, utilizing an active substructure splicing method, 20 new 1,2,4-oxadiazole compounds targeting LPOR were synthesized. Among them, compounds 5j, 5k and 5q exhibited superior inhibitory efficacy in greenhouse herbicidal trials. In vitro enzyme activity assays indicated that 5q significantly inhibited Arabidopsis thaliana LPOR (AtLPOR), with an IC₅₀ value of 17.63 μM. Furthermore, compound 5q exhibited superior crop safety and holds potential application prospects for weed management in cotton. Molecular docking and dynamic simulations were employed to elucidate the binding mode and molecular mechanism of 5q with AtLPOR. These experimental and theoretical results indicate that 5q is a promising candidate for the development of novel herbicides targeting LPOR. Full article

Ilex verticillata (winterberry) is a valuable ornamental shrub increasingly threatened by leaf blight, a disease that compromises its aesthetic and economic value. While fungal pathogens like Alternaria alternata are known to cause leaf blight in horticultural crops, their role in I. verticillata and the host’s defense mechanisms have not been fully characterized. Our study investigated the pathogen-host interaction by identifying the causal agent and examining the physiological and molecular defense mechanisms of I. verticillata. Through morphological and multi-locus molecular analyses (ITS, TEF1-α, G3PDH, RPB2), A. alternata was confirmed as the primary pathogen, fulfilling Koch’s postulates. Pathogenicity assays revealed distinct disease progression stages, from necrotic lesions to tissue degradation. Transcriptomic profiling uncovered dynamic host responses, with early upregulation of pattern recognition receptors (PRRs) and transcripts encoding antioxidant enzymes (SOD, CAT), followed by downregulation of metabolic pathway genes. Phytohormone analysis highlighted intricate crosstalk, with salicylic acid (SA) peaking during mid-infection and jasmonic acid (JA) rebounding later, reflecting a coordinated defense strategy. Additionally, the oxidative stress marker malondialdehyde (MDA), an indicator of membrane lipid peroxidation, surged early, indicating membrane damage, while sustained induction of antioxidant enzymes suggested adaptive responses. The key finding was distinct phytohormone crosstalk, characterized by a mid-infection SA peak followed by a late JA rebound, alongside an early oxidative burst marked by MDA accumulation and sustained antioxidant enzyme activity. These findings provide a framework for understanding I. verticillata’s defense mechanisms and offer insights for developing targeted disease management strategies, such as resistant cultivar breeding or hormone-mediated interventions. Full article