Defense Reactions Research Articles

Modification of peroxidase activity and proteome in maize exposed to cadmium in the presence of galactoglucomannan oligosaccharides.

We tested the effects of galactoglucomannan oligosaccharides (GGMOs) and/or cadmium (Cd) on peroxidase activity and the proteome in maize (Zea mays L.) roots and leaves. Our previous work confirmed that GGMOs ameliorate the symptoms of Cd stress in seedlings. Here, the plants were hydroponically cultivated for 7 days, and the protein content and peroxidase activity were estimated in intracellular, neutral cell wall, and acidic cell wall protein fractions. The peroxidase activity varied between the plant organs as well as among the fractions and treatments. The GGMOs in the presence of Cd did not significantly influence content of peroxidases but modulated their activity, which implies posttranslational regulation. The changes in the content of various proteins (e.g., related to the defence reactions, cell wall structure/metabolism, and activation of plant hormones) caused by GGMOs and Cd indicate possible protective mechanisms that improve the vitality of maize seedlings exposed to metal stress. GGMOs partially reverted Cd-induced protein disbalance, which was a reoccurring phenomenon of mitigation in leaves.

Anti Inflammation Effectivity Gel Formulated From Ethanol Extract of Ketepeng Cina Leaves (Cassia alata L.) Leaves

ABSTRACT Metabolites including flavonoids, tannins, saponins, alkaloids, terpenoids, anthraquinones, phenolics, glucose, and phytosterols are present in the Ketepeng Cina (Cassia alata L.) plant. When physical stress causes tissue injury, inflammation is the body's natural defensive reaction. This research aim to formulate gel preparation from ethanol extract of ketepeng cina leaves and determine its antiinflammatory activity on carrageenan induced mice (Mus musculus). This is experimental research, including collection of materials and prociessing of materials, making simplisia, making ethanol extract with a concentration of 5%, 10% and 15%, making ethanol extract gel of Ketepeng Cina leaves and testing the anti-inflammatory effect on mice. The results showed that the ethanol extract can be formulated in the form of gel dosage form with concentrations of 5%, 10% and 15% and has a qualified quality preparation evaluation. The observation results showed that the percentage of Inflammation Inhibition at the 5th hour on the gel with a concentration of 15% was 100%. Statistical Analysis of One Way Anova the percentage of inflammation at the 5th hour to the 6th hour showed a significant difference. So it can be stated that the preparation of ethanol extract gel of Ketepeng Cina leaves has the best anti-inflammatory effect at a concentration of 15%.

The defensive reactions: How dissociative out-groups’ imitation of goal setting affects imitated consumers?

The defensive reactions: How dissociative out-groups’ imitation of goal setting affects imitated consumers?

The startle response and prepulse inhibition in psychosis and violence: A combined electromyography and electroencephalography study

Abstract There is a pressing need for biomarkers of violent behavior risk in psychosis. Previous research indicates that electrophysiological measures of automatic defensive reactions may have potential. The purpose of this study was to investigate associations between violent behavior in individuals with and without psychosis and electromyography (EMG) and electroencephalography (EEG) responses to startling auditory stimuli. EMG and EEG was recorded during an auditory startle paradigm from healthy controls (HC, n=211), individuals with psychosis and a history of violent behavior (violent-PSY, n=18), individuals with psychosis without a history of violence (nonviolent-PSY, n=32), and individuals with a history of violence without psychosis (violent non-PSY, n=22). We estimated the auditory startle response (ASR) and prepulse inhibition (PPI) using EMG (i.e., EMGASR and EMGPPI) and the auditory evoked potential (i.e., AEPASR and AEPPPI) of the EEG. There were no significant effects of group on the EMGASR (p = 0.10) or the 30-ms, 60-ms, and 120-ms prepulse + pulse EMGPPI amplitudes (p = 0.11, p = 0.19, and p = 0.50, respectively). The N1 amplitude of the AEPASR was reduced in the violent-PSY group (p = <.001) and the nonviolent-PSY group (p = .015) compared to HC. The P2 amplitude of the AEPASR was reduced in violent-PSY relative to nonviolent-PSY (p = .003), violent non-PSY (p = .016), and HC (p < .001). Together, these results show that EEG-based neural responses to startling auditory stimuli are promising biomarkers of violence risk in psychosis.

Ultrastructure of adrenal glands endocrinocytes after thermal skin injury under conditions of correction with cryo-lyophilized xenograft skin substrate

According to WHO studies, burn injuries are one of the most common injuries in the world, and their number has increased significantly due to the military actions in Ukraine. The adrenal glands, which regulates metabolism and participates in the body's defense reactions, is sensitive to burn injuries, which leads to morphological changes in the organ. The aim of the study was to investigate the ultrastructural changes in endocrinocytes of the adrenal glands after experimental thermal skin injury under conditions of correction with cryo-lyophilized xenograft skin substrate. A second-degree burn was modeled by applying heated copper plates to the skin of the back of laboratory male rats, which accounted for 18-20 % of the body surface. For electron microscopic analysis on days 7th, 14th, and 21st of the experiment, pieces of the adrenal glands were taken. They were fixed in a glutaraldehyde solution, post-fixed in osmium tetraoxide, and processed according to standard procedures. Ultrathin sections were contrasted with uranyl acetate and lead citrate, and submicroscopic changes were studied using a PEM-125K electron microscope. On the 7th day after the burn with correction (using a cryo-lyophilized xenograft skin substrate), moderate changes in the ultrastructure of the nuclei and organelles of the endocrinocytes were found. Mitochondrial hyperplasia, changes in the shape of the nuclei and the presence of small clumps of heterochromatin in the karyoplasm were observed. On the 14th day, under the conditions of correction, there were signs of restoration of the cell ultrastructure, in particular, the structure of the nucleus and the membrane of the zona glomerulosa cells was restored, ribosomes and hypertrophied mitochondria with an electronically bright matrix appeared, as well as numerous lipid droplets. After 21 days, the ultrastructure of the cells of the zona glomerulosa was restored, and lipid droplets were evenly distributed in the cytoplasm. In the zona reticularis and adrenal medulla, changes in the submicroscopic organization of endocrinocytes were insignificant. We observed a uniform distribution of secretory granules in the cytoplasm of chromaffinocytes, mitochondrial recovery and unchanged ultrastructural organization of the organelles of the synthetic apparatus. Thus, the results of the study confirmed that the cryo-lyophilized xenograft skin substrate effectively promotes the restoration of the ultrastructure of adrenal endocrinocytes, reducing the degree of damage to cytoplasmic membranes, organelles of the synthetic apparatus of cells, endocrinocyte nuclei, especially activating the regeneration processes in the late stages after thermal skin injury.

Linking soil characteristics, rhizosphere microbiome composition, and plant defence reaction to apple replant disease severity

Linking soil characteristics, rhizosphere microbiome composition, and plant defence reaction to apple replant disease severity

Melatonin improves cadmium tolerance in Salix viminalis by enhancing amino acid and saccharide metabolism, and increasing polyphenols

As a short-rotation woody plant, Salix viminalis has the potential for phytoremediation of cadmium (Cd), but it has poor tolerance to high Cd concentrations. Melatonin (MEL), a candidate bio-promoter, was considered to play an active role in plant responses to Cd. However, the molecular mechanism by which MEL regulates metabolic processes in plants to defend against Cd stress remain unclear. Transcriptomics and global untargeted metabolomic sequencing were used to investigate the rapid response of S. viminalis to high Cd concentrations during initial growth stage after foliar application of MEL. Four treatments were set up in a pot experiment involving foliar application of MEL on the first day, followed by irrigation with a Cd solution the next day. Significant variations in the relevant defence genes and metabolites in leaves exposed to Cd were observed between willows treated with and without MEL. Foliar application of MEL upregulated sulphur metabolism-related genes such as methionine and S-adenosylmethionine synthases in leaves exposed to Cd; glutamine content, which is the key point of nitrogen assimilation, also increased. Additionally, glycolysis and sucrose metabolic genes, including hexokinase, sucrose synthase, invertase, and the inositol phosphate metabolic gene myo-inositol-1-phosphate synthase were also upregulated in leaves. Moreover, MEL also upregulated genes related to the synthesis of flavonoids, anthocyanins, and proanthocyanins in the leaves. These results demonstrated that MEL improved amino acid and saccharide metabolism in the leaves of S. viminalis in response to Cd. It also improved the antioxidant capacity and Cd tolerance in S. viminalis leaves by enhancing synthetic capacity of polyphenol compounds. MEL may be involved in processes of photorespiration, ethylene metabolism, GABA shunt, nitric oxide metabolism, osmotic adjustment, and the synthesis of glutathione and ascorbate in S. viminalis under Cd stress. This series of metabolic changes in S. viminalis occurred within 24 h of the foliar application of MEL, which provided a sufficient substrate for subsequent defence reactions to cope with Cd stress. Our findings will help elucidate the molecular mechanism by which MEL regulates metabolic processes in plants in response to Cd challenges and guide the application of MEL to improve Cd phytoremediation efficiency.

Lotus resistance against Ralstonia is enhanced by Mesorhizobium and does not impair mutualism.

Legumes establish nitrogen-fixing symbioses with rhizobia. On the contrary, they can be attacked concomitantly by pathogens, raising the question of potential trade-offs between mutualism and immunity. In order to study such trade-offs, we used a tripartite system involving the model legume Lotus japonicus, its rhizobial symbiont Mesorhizobium loti and the soilborne pathogen Ralstonia solanacearum. We investigated the impact of mutualism on plant defense and the reciprocal influence of plant defense on mutualism. We found that Lotus age-related resistance against Ralstonia was improved by the interaction with rhizobia especially when nodulation is triggered. Conversely, age-related resistance did not compromise nodule organogenesis or functioning under pathogen attack. Proteomic characterization indicates that this resistance is associated with distinct proteome modifications in roots and nodules. This resistance questions the concept of interference between efficient defense reactions and mutualistic interactions and is of great interest for agricultural purposes as it not only restricts pathogen colonization, but would also preserve nitrogen fixation and yield.

Deciphering the role of growth regulators in enhancing plant immunity against herbivory.

Plants are central to global food production, and the pursuit of sustainability aims to enhance or preserve food quality while safeguarding the environment. Due to their immobility, plants are unable to evade unfavourable climatic setups or interactions with other living creatures. Upon their interaction with insect herbivores, plants face biotic stress, which is a constant challenge for plants, causing molecular, physiological, and biochemical changes and reducing their productivity. To combat biotic stress caused by herbivores, plants have evolved intricate defence mechanisms through growth regulators such as auxins, cytokinins, gibberellins, salicylic acid (SA), jasmonic acid (JA), ethylene (ET), abscisic acid (ABA), strigolactones and brassinosteroids. The intricate network of specific proteins, metabolites and certain phytohormones orchestrates plant defensive reactions, leading to their skilful coordination in responding to insect attacks. Comprehending the defence mechanisms holds the key to mitigating significant crop and economic losses. This review entails a comprehensive analysis of the role of growth regulators in enhancing plant immunity against herbivory, highlighting the substantial efforts by the scientific community to manage and mitigate damages from biotic stress in plants, ultimately contributing to the advancement of sustainable agriculture.

When Influencers Compare Brands: Defensive Processing of Sponsored Comparative Messages and Effects on Consumer Evaluations

Social media influencers comparing competing products helps draw the desirable consumer attention to their product recommendation. However, it may also risk backfiring, especially when the influencer post is sponsored by a given brand. In the present study, we explored consumer evaluations of sponsored influencer comparative marketing through two important defensive mechanisms—counterarguing and inferences of manipulative intent with a 2 (message appeal: noncomparative vs. comparative) × 2 (content sponsorship: organic vs. sponsored) between-subjects online experiment (N = 325). We found that when the post was sponsored, the comparative message generated significantly greater defensive reactions than the noncomparative message, leading to lower perceived trustworthiness and authenticity of the influencer, unfavorable brand attitude, and lower purchase intention. In contrast, when the post was organic, the observed difference diminished. Furthermore, we found more prominent effects via inferences of manipulative intent than counterarguing, suggesting that consumers considerably value the genuineness behind product promotion from influencers. These findings extend research on comparative advertising to the trending influencer marketing context, shedding novel light on mechanisms underlying consumer responses to sponsored comparative messaging.

Overgeneralization of autonomic defensive reactions in obesity

Generalizing defensive responses to new stimuli resembling learned threats is an adaptive process within an ever-changing environment. However, evaluation mechanisms excessively biased toward generalization (i.e., overgeneralization) may underlie anxiety-related symptoms. In the context of obesity, fear memory and fear generalization processes have never been investigated. In this study, participants with obesity and healthy participants as controls underwent a single-cue auditory fear conditioning paradigm and recognition memory tasks. We analyzed the autonomic reactions evoked by threat-predictive and new stimuli, as well as the recognition performance towards the same cues. We found that participants with obesity displayed similar autonomic defensive responses to a learned fearful stimulus, but enhanced reactions to new stimuli, when compared with the controls. We detected no significant differences between groups in recognition abilities. Our results provided the first evidence that obesity may widen fear generalization patterns. This alteration may encourage future research in investigating the link between emotional dysregulation and clinical anxiety-related symptoms in obesity.

Disorders of cervical maturation under wartime stressful conditions

Pregnancy itself is a prerequisite for stress reactions. Even in the physiological course, pregnancy has a certain impact on a woman’s psyche, and some authors even consider it as a crisis situation or a “period of psychological uncertainty”. Women have different types of reactions to pregnancy: from the absence of any psychological problems to neurotic personality development.All the hardships of wartime affect not only the mother’s organism and her psychological state, but also the state of the unborn fetus, which is programmed with certain physical and mental health characteristics for the rest of its life.To prevent these negative effects, pregnant women during the pregravid period and gestation should take preventive measures aimed at strengthening the organism’s defense reactions in adverse conditions. These include a rational nutritious diet, determination of a woman’s personality type by a perinatal psychologist and appropriate psychological practices, and sufficient supplementation of important vitamins and minerals with antioxidant and other protective properties.Pregnancy under the influence of prolonged chronic stress can be complicated not only by purely obstetric and perinatal problems, but also by disorders of the formation of the labour dominant and preparatory processes in the cervix. As a result, this can lead to miscarriage due to the development of tokophobia as a psychological component of these disorders.Cervical maturation before childbirth is a multifactorial process that includes numerous elements, complex processes at the psychological, systemic, tissue, cellular, gene and molecular levels. Comprehensive preparation of a woman’s organism for childbirth in conditions of chronic stress and certain tokophobia (a woman’s fear of childbirth and uncertainty of the future for her and her child during the war) is not only about preventing stressful effects during pregnancy (magnesium complexes with B vitamins – up to the 36th week), conducting a complex of psychoprophylactic therapy and psychophysiological preparation for childbirth from the 37th week, but also in local impact on the cervical state, taking into account changes in connective tissue and correction of the infectious factor at the same time of pregnancy. For this purpose it is advisable and reasonable to prescribe vaginal suppositories based on hyaluronic acid (HA) to accelerate preparatory changes in the cervical tissues by stimulating the synthesis of its own HA and with antibacterial effects due to a complex of plant extracts.

Beyond victimhood and perpetration: Reconstruction of the ingroup's historical role in eight Eastern and Western European countries under Nazi occupation

AbstractThe Nazi regime's aggressive expansion across Europe during WWII created a landscape of suffering, resistance, and collaboration. How do lay Europeans today reconstruct their ingroup's roles during Nazi occupation, and how do different role representations relate to defensive responses aimed at protecting the ingroup from threat? We tested two theoretical predictions: Following the identity threat prediction, we expected that denying culpability but endorsing morally favorable group representations (e.g., victim‐heroism) would represent an ingroup‐defensive strategy, correlating with other defensive responses, such as victim‐directed negativity or victim‐blaming. Following the identity management prediction, we expected that precisely accepting culpability and acknowledging threatening representations (e.g., willing collaboration with Germans) would form the basis for a defensive stance and thus correlate with defensive intergroup reactions. Analyzing data from nine European samples spanning eight countries (N = 5474), we found support for the identity management prediction in six contexts: Lay representations as willing collaborators were associated with negative collective emotions and correlated with victim‐directed negativity, whereas victim‐hero representations showed no such connections. The remaining three countries revealed a mixture of the two identity accounts. We discuss implications for understanding historical representations and identity protection in groups that were both victims and perpetrators of massive intergroup atrocities.

In vitro, modulation of the dominant intestinal microbiota in type 2 diabetics by controlling antimicrobial activity with the methanolic extract of Pistacia lentiscus L.

The intestinal microbiota has become known as the ‘second brain’ a complementary organ for most metabolic and defensive reactions. The study aims to investigate the potential of the methanolic extract of Pistacia lentiscus leaves to modulate the dominant flora in type 2 diabetic patients compared to healthy subjects, by controlling growth kinetics. Comparative study between the dominant flora of type two diabitics (DT2) and helthy subjects (HS) stools. Using fully sterilized experimental space and materials, the germs were isolated through an antimicrobial study, and their microbial growth kinetics, were analyzed both with and without phytotherapeutic treatment in vitro. This was carried out as part of a study into the effect of methanolic extract from the leaves of the Pistacia lentiscus L. plant harvested in north-west Algeria. The study found a decrease in the quantity of lactobacilli and streptococci in DT2 and an inverse relationship between enterobacteria and streptococci in all microbiotas. On the molecular side. The methanolic extract of P lentiscus leaves gave a super antimicrobial effect for E coli and Clostridium sp at concentrations below their Minimum Inhibitory Concentration (2 mg mL-1), compared with the other gram positives studied, lactobacillus and Streptococcus (4 mg mL-1). This beneficial action confirms the high antimicrobial effect of the methanolic extract of P lentiscus leaves with lower concentration for the quantitative restauration of intestinal microbiota, the intermediary between insoluno-resistance and metabolism. Pistacia lentiscus has the potential to modulate the dominant flora in type 2 diabetics, through its regulatory antimicrobial power.

Defensive behaviors and c-fos expression in the midbrain.

Pavlovian fear conditioning serves as a valuable method for investigating species-specific defensive reactions (SSDRs) such as freezing and flight responses. The present study examines the role of white noise under different experimental conditions. Given that white noise has been shown to elicit both conditional (associative) and unconditional (nonassociative) defensive responses, we compared the response to noise following three separate training conditions: shock-only, white noise paired with shock, and context-only. Results showed that baseline freezing level significantly changed across groups: Both the shock-only group and the white noise paired with shock group froze more than the context-only group on the test day. White noise evoked differential freezing between groups on day 2: The shock-only group froze more than the context-only group although both groups were never exposed to white noise during training. Further, an activity burst triggered by white noise was similar for the shock-only and white noise paired with shock groups during testing, although shock-only group was never exposed to white noise stimuli during training. This aligned with c-fos data, indicating similar c-fos activity levels across different periaqueductal gray (PAG) regions for both shock-only and white noise paired with shock groups. However, the driving force behind c-fos activation-whether freezing, activity burst, or a combination of both-remains uncertain, warranting further analysis to explore specific correlations between SSDRs and c-fos activity within the PAG and related brain areas.

Exploring physiotherapy strategies in arthrogenic muscle inhibition: A scoping review

Arthrogenic muscular inhibition (AMI) is the presynaptic continual reflex inhibition of the surrounding muscles. It is a defensive reaction that lowers motor neuron activity to prevent further damage; however, if it persists, it can cause muscle atrophy and weakness, which can cause functional limitations. It usually involves quadriceps muscle post knee injuries and surgeries. Though it can be appreciated at any joint post injury or surgery like shoulder , elbow and ankle. Recent studies shows that post injury or surgery, tissues respond by reflex inhibition mechanism and is unnoticed by many therapists. The aim of this review is to analyse the various approaches available in the physiotherapy rehabilitation for treating AMI of any joint and to know the best treatment approach to be used for optimising the effects of AMI. Total of 37 articles were considered to identify the different outcomes and interventions used in treating AMI. In conclusion, Effective physiotherapy interventions are necessary to address AMI and enhance joint function and muscle activation. NMES, cryotherapy, and certain strengthening exercises are a few examples of interventions that can help get past the neural inhibition limiting muscle activation surrounding an injured joint. The implementation of early physiotherapy interventions is essential for preventing muscle atrophy and regaining normal movement patterns. In order to advance patient rehabilitation and maximize healing and functional outcomes, a customized protocol with particular demands is required.

Plant resistance to pathogens as a result of gene interaction

Modern information on the genomics of plants and plants’ pathogens as well the achievements of molecular biology have made it possible to state the participation of gene products, proteins, in the organization of molecular complexes that are assembled to implement a certain character of the phenotype. The character of plant “resistance/sensitivity” to a certain biotic factor is also interesting because there is an interaction not only between the genes of one organism, but between the genes of organisms that lie in different kingdoms of life.Plant resistance to pathogens can be passive (provided mainly by characters of plant morphology) and active. Active resistance is formed as a result of the penetration of the pathogen or its elicitors and effectors into the plant. Active protection of the plant at the molecular level is expressed in the launch of the MAPK cascade, the accumulation of reactive oxygen species, and an increase in the flow of calcium ions to the cell. Active protection can be implemented on two levels. The first level, RTI (PAMP Triggered Immunity), develops in response to plant contact with a wide range of non-adapted pathogens. The resistance (immunity) that is formed in this case is called non-specific, or horizontal, or quantitative. The molecular instrument for initiating the defensive reaction is the PRR (Pattern Recognition Receptors). Adapted pathogens are able to overcome RTI by sending effectors to plant cells. These are protein molecules whose function is to create conditions within the cell that are more permissive to the pathogen. The effector can be recognized by the plant’s specific NLR (Nod-Like Receptors), and complementation occurs between the two. There are other specific plant molecules, nonNLR, with a different type of protein product interaction for recognition. In both cases, the second level of protection, ETI (Effector Triggered Immunity), develops. The set of molecular processes that occur at the second level of protection does not differ from the set of the first level, but the processes occur more intensively and are accompanied by the death of the affected cells. This prevents the further spread of the pathogen throughout the plant. The molecular events of the first and second levels of protection are not isolated. The interaction between them involving the products of plant genes and pathogen genes is described by the “zig-zag-zig”-model, invasion model, and the integrated iceberg model. The interaction of plant genes for effector recognition is described by the “guard” and “decoy” models. To initiate a defensive reaction, plant receptors, which can sometimes differentiate into sensors and helpers, form protein complexes, resistosomes.

Nitric oxide-signalling affects panic-like defensive behaviour and defensive antinociception neuromodulation in the prelimbic cerebral cortex

Rationale: The prelimbic division (PrL) of the medial prefrontal cortex (mPFC) is a key structure in panic. Objectives: To evaluate the role of nitric oxide (NO) in defensive behaviour and antinociception. Methods: Either Nω-propyl-L-arginine (NPLA) or Carboxy-PTIO was microinjected in the PrL cortex, followed by hypothalamic treatment with bicuculline. The exploratory behaviours, defensive reactions and defensive antinociception were recorded. Encephalic c-Fos protein was immunolabelled after escape behaviour. Results: NPLA (an inhibition of nNOs) decreased panic-like responses and innate fear-induced antinociception. The c-PTIO (a membrane-impermeable NO scavenger) decreased the escape behaviour. PrL cortex pre-treatment with c-PTIO at all doses decreased defensive antinociception. c-Fos protein was labelled in neocortical areas, limbic system, and mesencephalic structures. Conclusion: The NPLA and c-PTIO in the PrL/mPFC decreased the escape behaviour and defensive antinociception organised by medial hypothalamic nuclei. The oriented escape behaviour recruits neocortical areas, limbic system, and mesencephalic structures. These findings suggest that the organisation of defensive antinociception recruits NO-signalling mechanisms within the PrL cortex. Furthermore, the present findings also support the role of NO as a retrograde messenger in the PrL cortex during panic-like emotional reactions.

Effect of Magnetic Field and UV-C Radiation on Postharvest Fruit Properties

This review focuses on the recent information on the effect of different types of magnetic fields (MFs) and ultraviolet radiation (UV-C) on the processes that may finally affect fruit quality and its storage potential. Firstly, the biological effect of MFs on every plant’s growth and development level is described. The magnetic field interacts with a plant’s metabolism and changes the permeability of membranes affecting cells’ homeostasis. It also could affect early seedling development, stimulating enzyme activity and protein synthesis, and later on nutrient and water uptake of adult plants. In some cases, it makes plants more resilient, increasing their tolerance to environmental stresses. Also, MF treatment could lower the disease index of plants, thus improving the internal and external fruit quality indices. The second part of this review focuses on interesting perspectives of using UV-C radiation to reduce postharvest fruit diseases, but also to delay fruit ripening and senescence. The application of UV-C light to combat postharvest infections is associated with two mechanisms of action, such as direct elimination of microorganisms located on the fruit surface and indirect triggering of the plant’s defense reaction. Moreover, the use of hormetic doses of UV-C can additionally increase the nutritional properties of fresh fruit, lead to the accumulation of desired phytochemicals such as polyphenols, for example, to increase anthocyanin or resveratrol content, or elevate antioxidant activity.

Mass Spectrometry Imaging to map metabolites in plant-microbe interactions: grapevine as a case study

Every year, viticulture faces several disease outbreaks caused by pathogens with different life cycles and modes of action, and due to climate changes, the appearance of new pathogens is a concern for viticulture. To cope with the different pathogenic microorganisms, the plant must recognise the invading agent and arm itself with an arsenal of defence reactions, including the accumulation of antimicrobial metabolites.The modulation of plant metabolites is one of the first responses to biotic factors. Their rapid synthesis can greatly contribute to strengthening plant defence allowing it to adapt, minimise pathogen colonisation and survive. Despite the scientific community's efforts to characterise the grapevine defence responses to pathogens, the molecules involved in pathogen control and their specific localisation remain to be deciphered.Mass Spectrometry Imaging (MSI) analytical techniques enable one to visualise and map the spatial distribution of numerous biological molecules within plant tissues allowing a better understanding of their biosynthesis, localisation and function.In this review, we explore the applications of MSI techniques to the study of plant/microbe interactions focusing on grapevine studies. This review opens new doors to gain a comprehensive understanding of the dynamics and variations of metabolite profiles in grapevine organs, at different developmental stages and under various stress conditions. This knowledge is crucial for elucidating the role of specific metabolites in grapevine defence mechanisms, and for identifying specific regions of high or low metabolite production, which can contribute to targeted breeding to improve disease resistance traits and have an impact on grapevine productivity and quality.