Increased Stress Resistance Research Articles

Rhizosphere Bacteria

Abstract The review is devoted to the analysis of modern literature data on rhizosphere bacteria and their role in the vital activity of plants. The structure of the rhizosphere is characterized, the role of plants as centers of formation of microbial communities is shown, data on the taxonomic affiliation of the main groups of microorganisms inhabiting the rhizosphere are presented. The associative relationships of rhizobacteria with a partner plant and the modern concept of a holobiont as a combination of a plant organism and associated microorganisms are considered. The role of rhizobacteria in the processes of azo fixation is discussed in detail. The mechanisms of direct stimulation of plant growth through the synthesis of phytohormones, improvement of phosphorus and nitrogen nutrition and increase in stress resistance, as well as indirect stimulation through antagonism with respect to phytopathogenic microorganisms are presented. The criteria for the selection of rhizobacteria for practical purposes are discussed.

Plant membrane transporters function under abiotic stresses: a review.

In the present review, we discussed the detailed signaling cascades via membrane transporters that confer plant tolerance to abiotic stresses and possible significant use in plant development for climate-resilient crops. Plant transporters play significant roles in nutrient uptake, cellular balance, and stress responses. They facilitate the exchange of chemicals and signals across the plant's membrane by signal transduction, osmotic adjustment, and ion homeostasis. Therefore, research into plant transporters is crucial for understanding the mechanics of plant stress tolerance. Transporters have potential applications in crop breeding for increased stress resistance. We discuss new results about various transporter families (ABC, MATE, NRAMP, NRT, PHT, ZIP), including their functions in abiotic stress tolerance and plant development. Furthermore, we emphasize the importance of transporters in plant responses to abiotic stresses such as drought, cold, salt, and heavy metal toxicity, low light, flooding, and nutrient deficiencies. We discuss the transporter pathways and processes involved in diverse plant stress responses. This review discusses recent advances in the role of membrane transporters in abiotic stress tolerance in Arabidopsis and other crops. The review contains the genes discovered in recent years and associated molecular mechanisms that improve plants' ability to survive abiotic stress and their possible future applications by integrating membrane transporters with other technologies.

Разработка природоподобной технологии размножения низкорослых подвоев косточковых культур в закрытом грунте

Abstract. The creation of technologies in accordance with the directions for the introduction of environmentally friendly, resource-saving developments into agriculture is relevant. Accelerated reproduction of planting material of the "basic" and "proven" categories is considered equally important, which requires optimization of reproduction by green cuttings. Green cutting allows to significantly quickly increase the yield of cuttings from one mother plant, reducing the area of the mother plantations by 4-5 times. Its advantage is the genetic uniformity of own-root plants, contributing to the elimination of plant infection with diseases and pests, ensuring a shorter growing period, successful combination with other stages of recovery: microclonal reproduction, reproduction by green grafting. In the protected ground conditions, studies were carried out (2019-2023) to isolate the most effective drug for the reproduction of healthy mother rootstock bushes for small-stone crops: AI 5 B, 3-20, AI-1.10-18, 3-107 (FSBSI NCFSCHVW breeding); VSL-2 (Crimean EBS breeding). The effect of the drugs was compared: plant growth regulators: Indolyl-3-butyric acid (IMC, SP), Phytactive Extraplus, CE; microbiological fertilizers: Sporex, Zh, Ultrex, Zh; Sporion, Zh, control (water). It was found that the treatment of BCI and the phytactive Extraplus reduced the period of appearance of primary roots by 4.5 and 5 days, depending on the rootstock. The largest percentage of rooted ones was obtained using the microbiological preparation Ultrex (3-47 % more than the control variant, depending on the rootstock genotype), also in this variant, due to its positive effect on root formation of more than 2 mm, increased stress resistance, more standard planting material was obtained by 90 % relative to the control ones. Key words: basic mother plantings, green cuttings, plant growth regulators, preparations based on microorganisms and their waste products, the percentage of yield of standard rootstocks for sweet cherries and cherries.

The role of exopolysaccharides Psl and Pel in resistance of Pseudomonas aeruginosa to the oxidative stressors sodium hypochlorite and hydrogen peroxide.

Biofilms are microbial communities of cells embedded in a self-produced polymeric matrix composed of polysaccharides, proteins, lipids, and extracellular DNA. Biofilm bacteria have been shown to possess unique characteristics, including increased stress resistance and higher antimicrobial tolerance, leading to failures in bacterial eradication during chronic infections or in technical settings, including drinking and wastewater industries. Previous studies have shown that in addition to conferring structure and stability to biofilms, the polysaccharides Psl and Pel are also involved in antibiotic resistance. This work provides evidence that these biofilm matrix components also contribute to the resistance of Pseudomonas aeruginosa to oxidative stressors including the widely used disinfectant NaOCl. Understanding the mechanisms by which bacteria escape antimicrobial agents, including strong oxidants, is urgently needed in the fight against antimicrobial resistance and will help in developing new strategies to eliminate resistant strains in any environmental, industrial, and clinical setting.

Overexpression of mitochondrial fission or mitochondrial fusion genes enhances resilience and extends longevity.

The dynamicity of the mitochondrial network is crucial for meeting the ever-changing metabolic and energy needs of the cell. Mitochondrial fission promotes the degradation and distribution of mitochondria, while mitochondrial fusion maintains mitochondrial function through the complementation of mitochondrial components. Previously, we have reported that mitochondrial networks are tubular, interconnected, and well-organized in young, healthy C. elegans, but become fragmented and disorganized with advancing age and in models of age-associated neurodegenerative disease. In this work, we examine the effects of increasing mitochondrial fission or mitochondrial fusion capacity by ubiquitously overexpressing the mitochondrial fission gene drp-1 or the mitochondrial fusion genes fzo-1 and eat-3, individually or in combination. We then measured mitochondrial function, mitochondrial network morphology, physiologic rates, stress resistance, and lifespan. Surprisingly, we found that overexpression of either mitochondrial fission or fusion machinery both resulted in an increase in mitochondrial fragmentation. Similarly, both mitochondrial fission and mitochondrial fusion overexpression strains have extended lifespans and increased stress resistance, which in the case of the mitochondrial fusion overexpression strains appears to be at least partially due to the upregulation of multiple pathways of cellular resilience in these strains. Overall, our work demonstrates that increasing the expression of mitochondrial fission or fusion genes extends lifespan and improves biological resilience without promoting the maintenance of a youthful mitochondrial network morphology. This work highlights the importance of the mitochondria for both resilience and longevity.

High Concentrations of Se Inhibited the Growth of Rice Seedlings.

Selenium (Se) is crucial for both plants and humans, with plants acting as the main source for human Se intake. In plants, moderate Se enhances growth and increases stress resistance, whereas excessive Se leads to toxicity. The physiological mechanisms by which Se influences rice seedlings' growth are poorly understood and require additional research. In order to study the effects of selenium stress on rice seedlings, plant phenotype analysis, root scanning, metal ion content determination, physiological response index determination, hormone level determination, quantitative PCR (qPCR), and other methods were used. Our findings indicated that sodium selenite had dual effects on rice seedling growth under hydroponic conditions. At low concentrations, Se treatment promotes rice seedling growth by enhancing biomass, root length, and antioxidant capacity. Conversely, high concentrations of sodium selenite impair and damage rice, as evidenced by leaf yellowing, reduced chlorophyll content, decreased biomass, and stunted growth. Elevated Se levels also significantly affect antioxidase activities and the levels of proline, malondialdehyde, metal ions, and various phytohormones and selenium metabolism, ion transport, and antioxidant genes in rice. The adverse effects of high Se concentrations may directly disrupt protein synthesis or indirectly induce oxidative stress by altering the absorption and synthesis of other compounds. This study aims to elucidate the physiological responses of rice to Se toxicity stress and lay the groundwork for the development of Se-enriched rice varieties.

EU Energy Securitisation: Ukraine's Place in the European Energy System

This article focuses on the investigation of the European Union's securitisation policy in the energy sector, in particular, the provision of energy carriers to the Union, which was developed in response to Russia's energy wars of 2006–2007 and 2008–2009 against Ukraine and indirectly against the European Union. The theory of securitisation, formulated by S. Ozkan, B. Buzan and other researchers, focuses not so much on eliminating the consequences of crises as on creating a system of securitisation for the relevant industries with increased stress resistance, diversification of economic and technological ties with partners and strengthening the social orientation of their functioning. The algorithmization of this policy and the changes that led to the institutional response to Russian aggression in the energy sector are investigated. The research is based on the approach of sociological (neo)institutionalism, which allows explaining political processes in terms of not only economic benefits, but also their importance for the development of other spheres of public life and international cooperation. This approach is based on the notion that, first, the institutional environment in which a particular institution operates provides it with the necessary resources, as well as legitimates and regulates its activities. As a result, sociological institutionalism emphasises the role of norms, rules, and culture, influencing the self-identification of actors associated with this institution, as well as defining „friends” and „foes” in the overall institutional structure. It is shown that changes in the EU energy policy are dictated not only by economic or technological considerations, but also by the requirement to meet the needs of the population and economy of the EU member states. At the same time, Ukraine's inclusion in the EU's common securitisation system is in the economic, political, and social interests of Ukraine, which, both under the Association Agreement and in the event of its accession to the EU, will have the status of an acceptor country. The article considers possible options for the EU and Ukraine to establish Ukraine as the EU's eastern securitizer and their respective consequences for both parties.

Correlated changes in stress resistance and biochemical parameters in response to long-term protein restriction in Drosophila melanogaster.

Studies in fruit flies, Drosophila melanogaster, have observed considerable variation in the effect of dietary protein restriction (PR) on various fitness traits. In addition, not only are there inconsistent results relating lifespan to stress resistance, but also the long-term effects of PR are unexplored. We study PR implementation across generations (long term) hypothesizing that it will be beneficial for fitness traits, stress resistance and storage reserves due to nutritional plasticity transferred by parents to offspring in earlier Drosophila studies. By imposing two concentrations of PR diets (50% and 70% of control protein) from the pre-adult and adult (age 1 day) stages of the flies, we assessed the stage-specific and long-term effect of the imposed PR. All long-term PR flies showed increased resistance against the tested stressors (starvation, desiccation, H2O2-induced oxidative stress). In addition, we also found long-term PR-induced increased stress resistance across generations. The PR flies also possessed higher protein and triglyceride (TG) content, reduced glucose and unaffected glycogen levels. We also assayed the effect of returning the PR flies to control (AL) food for a single generation and assessed their biochemical parameters to witness the transient PR effect. It was seen that TG content upon reversal was similar to AL flies except for PRI70 males; however, the glucose levels of PR males increased, while they were consistently lower in females. Taken altogether, our study suggests that long-term PR implementation contributes to increased stress resistance and was found to influence storage reserves in D. melanogaster.

Fmo induction as a tool to screen for pro-longevity drugs.

Dietary restriction (DR) and hypoxia (low oxygen) extend lifespan in Caenorhabditis elegans through the induction of a convergent downstream longevity gene, fmo-2. Flavin-containing monooxygenases (FMOs) are highly conserved xenobiotic-metabolizing enzymes with a clear role in promoting longevity in nematodes and a plausible similar role in mammals. This makes them an attractive potential target of small molecule drugs to stimulate the health-promoting effects of longevity pathways. Here, we utilize an fmo-2 fluorescent transcriptional reporter in C. elegans to screen a set of 80 compounds previously shown to improve stress resistance in mouse fibroblasts. Our data show that 19 compounds significantly induce fmo-2, and 10 of the compounds induce fmo-2 more than twofold. Interestingly, 9 of the 10 high fmo-2 inducers also extend lifespan in C. elegans. Two of these drugs, mitochondrial respiration chain complex inhibitors, interact with the hypoxia pathway to induce fmo-2, whereas two dopamine receptor type 2 (DRD2) antagonists interact with the DR pathway to induce fmo-2, indicating that dopamine signaling is involved in DR-mediated fmo-2 induction. Together, our data identify nine drugs that each (1) increase stress resistance in mouse fibroblasts, (2) induce fmo-2 in C. elegans, and (3) extend nematode lifespan, some through known longevity pathways. These results define fmo-2 induction as a viable approach to identifying and understanding mechanisms of putative longevity compounds.

Regulatory mechanisms of plant rhizobacteria on plants to the adaptation of adverse agroclimatic variables

The mutualistic plant rhizobacteria which improve plant development and productivity are known as plant growth-promoting rhizobacteria (PGPR). It is more significant due to their ability to help the plants in different ways. The main physiological responses, such as malondialdehyde, membrane stability index, relative leaf water content, photosynthetic leaf gas exchange, chlorophyll fluorescence efficiency of photosystem-II, and photosynthetic pigments are observed in plants during unfavorable environmental conditions. Plant rhizobacteria are one of the more crucial chemical messengers that mediate plant development in response to stressed conditions. The interaction of plant rhizobacteria with essential plant nutrition can enhance the agricultural sustainability of various plant genotypes or cultivars. Rhizobacterial inoculated plants induce biochemical variations resulting in increased stress resistance efficiency, defined as induced systemic resistance. Omic strategies revealed plant rhizobacteria inoculation caused the upregulation of stress-responsive genes—numerous recent approaches have been developed to protect plants from unfavorable environmental threats. The plant microbes and compounds they secrete constitute valuable biostimulants and play significant roles in regulating plant stress mechanisms. The present review summarized the recent developments in the functional characteristics and action mechanisms of plant rhizobacteria in sustaining the development and production of plants under unfavorable environmental conditions, with special attention on plant rhizobacteria-mediated physiological and molecular responses associated with stress-induced responses.

Use of non-invasive mesodiencephalic brain modulation for enhancing stress resistance in athletes

BACKGROUND: During many years of intensive training, professional athletes may experience manifestations of stress due to significant physical and emotional stress, which require corrective measures. AIM: The aim of the study is to evaluate the effectiveness of mesodiencephalic modulation of the brain to increase stress resistance in athletes. MATERIALS AND METHODS: A prospective study was conducted, in which 57 athletes of complex coordination sports took part, of which 42 were girls and 15 were young men, the average age of the subjects was 18 ± 5,4 years. Two groups were formed: main (n = 35) and control (n = 22). To assess the functional capabilities of the body, all subjects included in the study were assessed for nonspecific adaptation responses by the percentage of lymphocytes and the ratio of leukogram elements in peripheral blood, and the level of adaptation and anxiety was assessed using structured questionnaires. Athletes of the main group (n = 35) underwent a course of mesodiencephalic modulation of the brain. RESULTS: The increase in adaptation capabilities in the control group was due to an increase in the frequency of the increased activation reaction, and in the main group — a calm activation reaction, which, in the presence of stress, is a more favorable adaptation state. CONCLUSIONS: The use of non-invasive mesodiencephalic modulation of the brain to increase stress resistance in athletes is advisable. Course of mesodiencephalic modulation of brain by cycle consisting of 10 procedures, duration 30 min, average intensity — 1.19 mA, allows to reduce level of psychoemotional tension, to improve general well-being, to increase speed of recovery processes after training. The course of mesodiencephalic modulation contributed to an increase in the adaptation capabilities of the body of athletes.

Artificial diets can manipulate the reproductive development status of predatory ladybird beetles and hold promise for their shelf-life management

With the development of biological control methods, the predatory ladybird beetle Harmonia axyridis Pallas (Coleoptera: Coccinellidae) has been widely used for pest control in agricultural production. Appropriate shelf-life management strategies could synchronize H. axyridis production with pest outbreaks, finally improving the effectiveness of biological control. Herein, we preliminarily explored whether an artificial diet could optimize the shelf-life management of H. axyridis. We compared the survival rate, nutrition accumulation, reproductive development, juvenile hormone (JH) related-gene expression levels, and stress resistance gene expression levels between aphid-fed and artificial diet-fed H. axyridis females. The results revealed that H. axyridis females maintained a high survival rate after being fed an artificial diet for 60 days, whereas the survival rate of aphid-fed females decreased. Continuous feeding of the artificial diet caused H. axyridis females to enter a diapause-like state, which was characterized by low JH levels, high triglycerides and trehalose accumulation, ovarian development inhibition, decreased Vgs expression levels, and increased stress resistance gene expression levels. This diapause-like state could be promptly recovered upon transferring to an aphid diet. These results indicate that the artificial diet could manipulate the reproductive development status of H. axyridis and lay the foundation for its shelf-life management.

Mutation breeding of high-stress resistant strains for succinic acid production from corn straw

The production of succinic acid from corn stover is a promising and sustainable route; however, during the pretreatment stage, byproducts such as organic acids, furan-based compounds, and phenolic compounds generated from corn stover inhibit the microbial fermentation process. Selecting strains that are resistant to stress and utilizing nondetoxified corn stover hydrolysate as a feedstock for succinic acid production could be effective. In this study, A. succinogenes CICC11014 was selected as the original strain, and the stress-resistant strain A. succinogenes M4 was obtained by atmospheric and room temperature plasma (ARTP) mutagenesis and further screening. Compared to the original strain, A. succinogenes M4 exhibited a twofold increase in stress resistance and a 113% increase in succinic acid production when hydrolysate was used as the substrate. By conducting whole-genome resequencing of A. succinogenes M4 and comparing it with the original strain, four nonsynonymous gene mutations and two upstream regions with base losses were identified.Key points• A high-stress-resistant strain A. succinogenes M4 was obtained by ARTP mutation• The production of succinic acid increased by 113%• The mutated genes of A. succinogenes M4 were detected and analyzedGraphical

Abstract 2091: Pharmacological inhibition of chaperone-mediated autophagy via NCoR1/RARα targeting is effective against non-small cell lung cancer

Abstract Dysregulation of autophagy, the lysosomal degradation of intracellular components, has been universally described in cancer. While activity of macroautophagy changes in a context-dependent manner in cancers, the upregulation of chaperone-mediated autophagy (CMA) is well-described in all solid tumors studied to date. Upregulated CMA directly contributes to both tumor growth and protection against anti-oncogenic interventions in cancers. Selective degradation of anti-oncogenic and pro-apoptotic proteins, such as mutant p53 and PUMA, misfolded proteins, and glycolytic enzymes by CMA allows for increased survival, reduced cell death, increased stress resistance, and enhancement of the Warburg effect in cancer cells, respectively. As such, inhibition of CMA is an attractive target for anti-cancer therapeutics, but the field currently lacks protein targets specific to CMA and selective CMA inhibitors. We have previously demonstrated the regulatory effect of retinoic acid receptor alpha (RARα) and its coregulator, nuclear receptor corepressor 1 (NCoR1), on CMA through transcriptional upregulation of the CMA effector proteins (Bourdenx et al. Cell 2021, Gomez-Sintes et al, Nat. Commun. 2022). Here, we identified a high NCoR1/RARα expression ratio in human non-small cell lung cancer (NSCLC) tumors compared to healthy lung tissue. We further illustrated a dependency on NCoR1 expression and its interaction with RARα to maintain high CMA activity in NSCLC cell lines. Provided the reliance on NCoR1 repression of RARα for high CMA activity in NSCLC, we hypothesized that small molecule targeting of the druggable NCoR1/RARα interaction to disrupt the interaction may result in suppression of CMA effector proteins and CMA inhibition. Through a series of in-silico screens for predicted NCoR1/RARα targeting, and functional screens for CMA inhibition, we identified CIM7, a first-in-class potent and selective CMA inhibitor. We validated CIM7 function through binding to RARα and subsequent disruption of NCoR1 binding, resulting in alterations to CMA-related gene expression. CIM7 inhibits CMA in vivo with no observed toxicity in normal tissues. We additionally demonstrated the therapeutic potential of CIM7 through its ability to reduce tumor growth in vivo in mouse NSCLC xenografts. Our findings support the NCoR1/RARα interaction as a major regulator of CMA in NSCLC and demonstrate the potential of pharmacologic CMA inhibition as an anti-cancer therapeutic strategy. Citation Format: Mericka McCabe, Rabia R. Khawaja, Rajanya Bhattacharyya, Antonio Diaz, Thomas P. Garner, Kristen Lindenau, Rebecca Sereda, Olaya Santiago-Fernández, Ana Maria Cuervo, Evripidis Gavathiotis. Pharmacological inhibition of chaperone-mediated autophagy via NCoR1/RARα targeting is effective against non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2091.

Oxidative stress is intrinsic to staphylococcal adaptation to fatty acid synthesis antibiotics

Antibiotics inhibiting the fatty acid synthesis pathway (FASII) of the major pathogen Staphylococcus aureus reach their enzyme targets, but bacteria continue growth by using environmental fatty acids (eFAs) to produce phospholipids. We assessed the consequences and effectors of FASII-antibiotic (anti-FASII) adaptation. Anti-FASII induced lasting expression changes without genomic rearrangements. Several identified regulators affected the timing of adaptation outgrowth. Adaptation resulted in decreased expression of major virulence factors. Conversely, stress responses were globally increased and adapted bacteria were more resistant to peroxide killing. Importantly, pre-exposure to peroxide led to faster anti-FASII-adaptation by stimulating eFA incorporation. This adaptation differs from reports of peroxide-stimulated antibiotic efflux, which leads to tolerance. Invivo, anti-FASII-adapted S.aureus killed the insect host more slowly but continued multiplying. We conclude that staphylococcal adaptation to FASII antibiotics involves reprogramming, which decreases virulence and increases stress resistance. Peroxide, produced by the host to combat infection, favors anti-FASII adaptation.

A single point mutation in the Listeria monocytogenes ribosomal gene rpsU enables SigB activation independently of the stressosome and the anti-sigma factor antagonist RsbV.

Microbial population heterogeneity leads to different stress responses and growth behavior of individual cells in a population. Previously, a point mutation in the rpsU gene (rpsUG50C) encoding ribosomal protein S21 was identified in a Listeria monocytogenes LO28 variant, which leads to increased multi-stress resistance and a reduced maximum specific growth rate. However, the underlying mechanisms of these phenotypic changes remain unknown. In L. monocytogenes, the alternative sigma factor SigB regulates the general stress response, with its activation controlled by a series of Rsb proteins, including RsbR1 and anti-sigma factor RsbW and its antagonist RsbV. We combined a phenotype and proteomics approach to investigate the acid and heat stress resistance, growth rate, and SigB activation of L. monocytogenes EGDe wild type and the ΔsigB, ΔrsbV, and ΔrsbR1 mutant strains. While the introduction of rpsUG50C in the ΔsigB mutant did not induce a SigB-mediated increase in robustness, the presence of rpsUG50C in the ΔrsbV and the ΔrsbR1 mutants led to SigB activation and concomitant increased robustness, indicating an alternative signaling pathway for the SigB activation in rpsUG50C mutants. Interestingly, all these rpsUG50C mutants exhibited reduced maximum specific growth rates, independent of SigB activation, possibly attributed to compromised ribosomal functioning. In summary, the increased stress resistance in the L. monocytogenes EGDe rpsUG50C mutant results from SigB activation through an unknown mechanism distinct from the classical stressosome and RsbV/RsbW partner switching model. Moreover, the reduced maximum specific growth rate of the EGDe rpsUG50C mutant is likely unrelated to SigB activation and potentially linked to impaired ribosomal function.

Ancient bayberry increased stress resistance by enriching tissue-specific microbiome and metabolites.

The ancient bayberry demonstrates superior resistance to both biotic and abiotic stresses compared to cultivated bayberry, yet the underlying mechanisms remain largely unexplored. This study investigates whether long-term bayberry cultivation enhances stress resistance through modulation of tissue-specific microbes and metabolites. Employing microbiome amplicon sequencing alongside untargeted mass spectrometry analysis, we scrutinize the role of endosphere and rhizosphere microbial communities and metabolites in shaping the differential resistance observed between ancient and cultivated bayberry trees. Our findings highlight the presence of core microbiome and metabolites across various bayberry tissues, suggesting that the heightened resistance of ancient bayberry may stem from alterations in rhizosphere and endosphere microbial communities and secondary metabolites. Specifically, enrichment of Bacillus in roots and stems, Pseudomonas in leaves, and Mortierella in rhizosphere soil of ancient bayberry was noted. Furthermore, correlation analysis underscores the significance of enriched microbial species in enhancing ancient bayberry's resistance to stresses, with elevated levels of resistance-associated metabolites such as beta-myrcene, benzothiazole, L-glutamic acid, and gamma-aminobutyric acid identified through GC-MS metabolomics analysis. The beneficial role of these resistance-associated metabolites was further elucidated through assessment of their promotive and allelopathic effects, as well as their phytostatic and antioxidant functions in lettuce plants. Ultimately, our study delves into the intrinsic reasons behind the greater resistance of ancient bayberry to biotic and abiotic stresses by evaluating the impact of long-term planting on the microbial community and metabolites in the bayberry endosphere and rhizosphere, shedding light on the complex dynamics of host-microbial interactions.

The effect of nettle extract on antioxidant defense system in piglets after weaning

Background. The effect of common nettle (Urtica dioica L.) extracts on the free radical processes and antioxidant system in piglets during the critical period of weaning from sows has been studied. Materials and Methods. Large white piglets were divided into 2 groups (control and experimental), 9 animals in each. Piglets of the experimental group from 14 days of age and before weaning received the standard diet and the nettle extract in the dose of 6 mg/kg of body weight for 22 days. The blood, as well as erythrocyte hemolysates and plasma of piglets obtained at 14, 36, and 42 days of age, were studied. Results. Our results have shown that weaning causes an oxidative stress in piglets. This state leads to an increase in the concentration of metabolites of free radical damage to protein molecules – carbonyl groups of proteins on the first day and primary products of lipid peroxidation on the seventh day after weaning. This activation of oxidative damage occurs in piglets against the background of a physiologically immature antioxidant system and is characterized by a decrease in the activity of the enzymatic chain – superoxide dismutase, glutathione peroxidase and catalase, as well as the concentration of its non-enzymatic antioxidant – reduced glutathione. Feeding piglets with nettle extract leads to activation of the antioxidant defense system in erythrocytes (higher activity of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and an increased reduced glutathione level compared to the control values) and a decrease in the concentration of oxidative damage products in the plasma (the content of lipid hydroperoxides, TBA-active products and carbonyl groups of proteins). Conclusion. The positive effect of nettle extract on the inhibition of free radical processes and activation of antioxidant systems indicates that this extract can be added to the standard diet of young animals to increase stress resistance and adaptability of their organism in critical periods of ontogenesis.

Genome stability of <i>Bacillus velezensis</i> after two-year exposure in open space

Spore-forming bacteria have a unique resistance to negative environmental conditions, including aggressive space factors, and are an excellent model for studying adaptation mechanisms and survival strategies at the molecular level. The study analyzed the genome of Bacillus velezensis, which remained viable after a two-year exposure in outer space on the outer surface of the ISS as part of the Test space experiment. A comparative analysis of the draft genomes of the exhibit strain and the ground control did not reveal significant changes, the average nucleotide identity was 99.98%, which indicates the ability of microorganisms to maintain genome stability in space conditions, due to both increased stress resistance of bacterial spores and efficient operation of the system. repair of accumulated changes. The study of single nucleotide polymorphism in the genome of Bacillus velezensis revealed nine point substitutions, three of which are in intergenic regions, 6 in protein-coding genes, three of them are missense mutations, two nucleotide deletions leading to a shift in the reading frame, and one synonymous substitution. The profiles of the housekeeping genes were determined during MLST typing, and it was found that the allelic profiles obtained for B. velezensis T15.2 and 924 strains do not correspond to any of the previously described sequence types. The presented results indicate the ability of Bacillus velezensis bacteria to maintain the viability of spores and the integrity of the genome for a long time under extreme conditions of outer space, which is important for the problem of planetary protection, as well as the potential possibility of implementing biotechnological processes based on Bacillus velezensis during space exploration.

Abnormal stress promotes intervertebral disc degeneration through WTAP/YTHDF2-dependent TIMP3 m6A modification.

Mechanical environment worsening is an important predisposing factor that accelerates intervertebral disc degeneration (IDD), but its specific regulatory mechanisms remain unclear. In this study, we reveal the molecular mechanisms of WTAP/YTHDF2-mediated m6A modification in abnormal stress-induced intervertebral disc (IVD) matrix degradation. WTAP expression in human nucleus pulposus cells was elevated under tension. Similarly, high WTAP expression was detected in severe degenerated human and rat nucleus pulposus tissues. Functionally, WTAP was found to increase the TIMP3 transcript methylation level under tension, resulting in YTHDF2 recognition, binding, and induction of its degradation. Reduction in TIMP3 caused increases in active matrix metalloproteinases, ultimately inducing extracellular matrix degradation in nucleus pulposus cells. Macroscopically, this promotes IDD. Additionally, in vitro and in vivo inhibition of WTAP expression or TIMP3 overexpression significantly increased stress resistance in the nucleus pulposus, thereby alleviating IDD. Our results show that abnormal stress disrupts IVDmatrix stability through WTAP/YTHDF2-dependent TIMP3 m6A modification.