Oxidative Stress Response Research Articles

Calcium bridges built by mitochondria-associated endoplasmic reticulum membranes: potential targets for neural repair in neurological diseases

The exchange of information and materials between organelles plays a crucial role in regulating cellular physiological functions and metabolic levels. Mitochondria-associated endoplasmic reticulum membranes serve as physical contact channels between the endoplasmic reticulum membrane and the mitochondrial outer membrane, formed by various proteins and protein complexes. This microstructural domain mediates several specialized functions, including calcium (Ca2+) signaling, autophagy, mitochondrial morphology, oxidative stress response, and apoptosis. Notably, the dysregulation of Ca2+ signaling mediated by mitochondria-associated endoplasmic reticulum membranes is a critical factor in the pathogenesis of neurological diseases. Certain proteins or protein complexes within these membranes directly or indirectly regulate the distance between the endoplasmic reticulum and mitochondria, as well as the transduction of Ca2+ signaling. Conversely, Ca2+ signaling mediated by mitochondria-associated endoplasmic reticulum membranes influences other mitochondria-associated endoplasmic reticulum membrane-associated functions. These functions can vary significantly across different neurological diseases–such as ischemic stroke, traumatic brain injury, Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, and Huntington's disease–and their respective stages of progression. Targeted modulation of these disease-related pathways and functional proteins can enhance neurological function and promote the regeneration and repair of damaged neurons. Therefore, mitochondria-associated endoplasmic reticulum membranes-mediated Ca2+ signaling plays a pivotal role in the pathological progression of neurological diseases and represents a significant potential therapeutic target. This review focuses on the effects of protein complexes in mitochondria-associated endoplasmic reticulum membranes and the distinct roles of mitochondria-associated endoplasmic reticulum membranes-mediated Ca2+ signaling in neurological diseases, specifically highlighting the early protective effects and neuronal damage that can result from prolonged mitochondrial Ca2+ overload or deficiency. This article provides a comprehensive analysis of the various mechanisms of Ca2+ signaling mediated by mitochondria-associated endoplasmic reticulum membranes in neurological diseases, contributing to the exploration of potential therapeutic targets for promoting neuroprotection and nerve repair.

Glucocorticoids influence on rat hematological parameters and catalase activity

In this study, the impact of glucocorticoid, betamethasone dipropionate on enzyme activity in vitro and its effects on hematological parameters in vivo was investigated. The immobilized catalase, crucial for cell oxidative stress response via hydrogen peroxide reduction, exhibited a robust electrocatalytic response, maintaining its biological activity. The in vitro inhibition kinetics of catalase, as determined by electrocatalytic methods and expressed using Lineweaver-Burke diagrams, revealed an uncompetitive type of inhibition with altered Imax and Km in the presence of a range of betamethasone dipropionate concentrations. The in vivo experiments conducted on Rattus norvegicus demonstrated significant alterations in hematological parameters following betamethasone dipropionate administration. These changes included a decrease in erythrocyte count, an increase in hemoglobin, a reduction in mean corpuscular volume (MCV), and an elevation in mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC). Notably, the leukocyte counts substantially increased. The observed hematological shifts suggest an impact of betamethasone dipropionate on the hematopoietic system, reinforcing the need for cautious corticosteroid administration. The findings underline the necessity for judicious corticosteroid treatment, acknowledging both enzymatic and systemic repercussions.

Association of phenylalanine and tyrosine metabolism with mortality and response to nutritional support among patients at nutritional risk: a secondary analysis of the randomized clinical trial EFFORT

BackgroundElevated phenylalanine serum level is a surrogate marker of whole-body proteolysis and has been associated with increased mortality in critically ill patients. Tyrosine is a metabolite of phenylalanine and serves as a precursor of thyroid hormones and catecholamines with important functions in the oxidative stress response among others. Herein, we examined the prognostic significance of phenylalanine, tyrosine, as well as its metabolites nitrotyrosine, L-3,4-dihydroxyphenylalanine (DOPA), and dopamine regarding clinical outcomes and response to nutritional therapy in patients at nutritional risk.MethodsThis is a secondary analysis of the Effect of Early Nutritional Support on Frailty, Functional Outcomes, and Recovery of Malnourished Medical Inpatients Trial (EFFORT), a randomized controlled trial investigating individualized nutritional support compared to standard care in patients at risk of malnutrition. The primary outcome was 30-day all-cause mortality.ResultsWe analyzed data of 238 patients and found a significant association between low plasma levels of phenylalanine [adjusted HR 2.27 (95% CI 1.29 to 3.00)] and tyrosine [adjusted HR 1.91 (95% CI 1.11 to 3.28)] with increased 30-day mortality. This association persisted over a longer period, extending to 5 years. Additionally, trends indicated elevated mortality rates among patients with low nitrotyrosine and high DOPA and dopamine levels. Patients with high tyrosine levels showed a more pronounced response to nutritional support compared to patients with low tyrosine levels (HR 0.45 versus 1.46, p for interaction = 0.02).ConclusionIn medical inpatients at nutritional risk, low phenylalanine and tyrosine levels were associated with increased short-and long-term mortality and patients with high tyrosine levels showed a more pronounced response to nutritional support. Further research is warranted to gain a deeper understanding of phenylalanine and tyrosine pathways, their association with clinical outcomes in patients at nutritional risk, as well as their response to nutritional therapy.Clinical trial registrationwww.clinicaltrials.gov, identifier NCT02517476.

Vancomycin-induced acute kidney injury in rats: beneficial effects deriving from the co-administration of tadalafil or vitamin C

Background: Vancomycin (VAN) is widely employed in clinical settings for the treatment of severe infections attributable to multi-resistant bacteria, with a notable emphasis on Gram-positive strains. However, its therapeutic usage is significantly hampered by the potential for acute kidney injury (AKI); specifically, the nephrotoxic effects it can exert. In controlled experimental studies, the intraperitoneal (i.p.) administration of VAN at a dose of 400 mg/kg/day over a consecutive seven-day period has been shown to induce considerable AKI in rats. In addressing this concern, vitamin C (VC), recognized traditionally for its antioxidant properties, has been utilized to mitigate various forms of organ damage and inflammatory responses, primarily by diminishing oxidative stress and attenuating inflammation. Concurrently, tadalafil (TAD), a phosphodiesterase type-5 inhibitor commonly associated with the treatment of erectile dysfunction, is also noted for its beneficial anti-inflammatory and antioxidant effects, alongside vasodilatory properties. Aim: This study was designed in order to investigate the protective capabilities of TAD or VC against the VAN-induced nephrotoxic effects in a rat model of AKI. Methodology: A total of 24 male albino Wistar rats were allocated into four distinct groups for the purpose of comparative analysis. Following treatment, both kidney and blood samples were obtained for further evaluation. The study randomized the rats into four categories: group 1 served as the control group, group 2 received VAN at a dosage of 400 mg/kg (via an i.p. injection on a daily basis), group 3 was administered VAN (400 mg/kg; i.p., daily) in conjunction with TAD at a dose of 5 mg/kg daily, and group 4 was given VAN (400 mg/kg; i.p., daily) alongside VC at a dosage of 200 mg/kg daily. Results: Evaluations included the measurement of renal function indicators such as the serum levels of urea, of creatinine, and the creatinine clearance. Additionally, the analysis involved the assessment of antioxidant markers in renal tissue homogenates, including malondialdehyde (MDA), glutathione, and superoxide dismutase. To further elucidate the inflammatory response, indices such as the levels of the tumor necrosis factor-alpha, the interleukins (IL)-1β and IL-6, and the nuclear factor-κB were evaluated within the renal tissue homogenate samples of the studied rats. The administration of VAN resulted in a marked elevation of renal biomarkers and inflammatory indices, alongside a significant reduction in antioxidant levels, with an exception for MDA (which exhibited increased levels); these changes reached statistical significance (p<0.05) when measured against the control group. In contrast, the supplementation with TAD or VC was effective in significantly lowering the serum levels of both renal and inflammatory indicators when compared to the group treated solely with VAN. Furthermore, antioxidant measurements improved, alongside a reduction in MDA levels, thereby demonstrating significant differences (p<0.05). Conclusion: The findings of this study reveal that both TAD and VC provide a degree of renal protection against the VAN-induced damage by enhancing kidney function markers and, concurrently, lessening oxidative stress and inflammatory responses associated with nephrotoxicity.

Isofraxidin alleviated radiation-induced testicular damage via the Nrf2/HO-1-NLRP3/ASC Axis

OBJECTIVE: Radiotherapy is used to treat patients with tumors; however, radiation (IR)-induced testicular injury, which has no effective treatment approved in clinical practice, significantly influences their prognosis and quality of life. The protective effects and underlying mechanisms of action of isofraxidin (IF) against IR-induced testicular injury were investigated. Methods: A mouse testis injury model was established using 5 Gy irradiation. H&E staining, immunofluorescence staining, and enzyme-linked immunosorbent assay were used to measure DNA damage, apoptosis, inflammatory reactions, and oxidative stress in the testes of mice after irradiation. The effectiveness of IF irradiation on testicular injury was evaluated, and the mechanisms of the related oxidative stress and inflammatory response pathways are discussed. Results: IF can improve IR-induced testicular injury by inhibiting the increased levels of DNA damage, apoptosis rate, oxidative stress, and inflammatory factors. The radioprotective effects of IF on testicular injury are mediated by the stimulation of Nrf2/HO-1 or suppression of NLRP3 inflammasome signaling pathways. In addition, crosstalk between the Nrf2/HO-1 and NLRP3 inflammasome signaling pathways was elucidated, in which the inhibition of the NLRP3 inflammasome was mediated by the activation of Nrf2 signaling with IF upon IR exposure. Conclusion: IF can be a potent radioprotective agent to mitigate testicular damage, and may provide a new therapeutic option to alleviate the side effects of radiotherapy in male patients with tumors.

Synergistic Disinfection by 222 nm Far-UVC and Negative Air Ions of Airborne Bacteria and the Induced Oxidative Stress Responses: A Bioaerosol Chamber Study

Synergistic Disinfection by 222 nm Far-UVC and Negative Air Ions of Airborne Bacteria and the Induced Oxidative Stress Responses: A Bioaerosol Chamber Study

Synergistic effects of thermal stress and 4-nonylphenol on oxidative stress and immune responses in juvenile tilapia (Oreochromis niloticus)

Synergistic effects of thermal stress and 4-nonylphenol on oxidative stress and immune responses in juvenile tilapia (Oreochromis niloticus)

Inert Gas Mild Pressure Action on Healthy Humans: The “IPA” Study

The goal of this study was to evaluate inflammatory and oxidative stress responses in human subjects (9 females and 15 males) (age [29.6 ± 11.5 years old (mean ± SD)], height [172.0 ± 10.05 cm], and weight [67.8 ± 12.4 kg]) exposed to 1.45 ATA of helium (He) or nitrogen (N2) without concurrent hyperoxia. We hypothesized that elevated gas pressures would elicit an inflammatory response concurrent with oxidative stress. Consistent with ex vivo studies, both gasses elicited neutrophil activation, small elevations in microparticles (MPs) and increases in intra-MP interleukin (IL)-1β and inflammatory nitric oxide synthase, and an increase in urinary IL-6 concurrent with a marked reduction in plasma gelsolin. Mixed responses indictive of oxidative stress, with some biomarker elevations but little change in others and a decrease in some, were observed. Overall, these results demonstrate that exposure to typical diving gasses at a mildly elevated partial pressure will initiate inflammatory responses, which may play a significant role in decompression sickness (DCS). The complex pattern of oxidative stress responses may be indicative of competing systemic reactions and sampling different body fluids.

Effect of dietary Anabaena supplementation on nutrient utilization, metabolism and oxidative stress response in Catla catla fingerlings

A 60-day feeding trial was conducted to evaluate the effects of dietary Anabaena blue-green algae (ABGA) meal on the growth performance, digestibility, and physio-metabolic responses of Catla catla fingerlings (initial average weight 9.45 ± 0.15 g). Six iso-nitrogenous (30% crude protein) and iso-caloric (378.09 Kcal. digestible energy/100 g) diets were formulated: a control diet (A0, 0% ABGA) and five experimental diets with varying ABGA inclusion levels (A3: 3%, A6: 6%, A9: 9%, A12: 12%, A15: 15%). The results demonstrated that there were no significant differences (P > 0.05) in percentage weight gain (PWG), specific growth rate (SGR), protein efficiency ratio (PER), and feed conversion ratio (FCR) among the experimental groups. Additionally, dietary ABGA did not significantly affect (P > 0.05) body carcass composition among different groups. However, amylase activity significantly decreased (P < 0.05) in the A12 and A15 fed groups, whereas lipase and protease activities remained insignificant (P > 0.05) across all groups. Notably, oxidative stress responses (SOD; superoxide dismutase and CAT; catalase), carbohydrate metabolic enzymes (LDH; lactate dehydrogenase and MDH; malate dehydrogenase), and serum glucose levels increased significantly (P < 0.05) with higher ABGA inclusion. Conversely, serum albumin content significantly decreased (P < 0.05) in the ABGA-fed groups. There were no significant differences (P > 0.05) observed in serum total protein, albumin/globulin (A/G) ratio, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) activities among the experimental groups. Hematological parameters revealed that RBC (red blood cell) count, hemoglobin (Hb) concentration, and packed cell volume (PCV) significantly decreased (P < 0.05), while WBC (white blood cell) count significantly (P < 0.05) increased with higher dietary ABGA inclusion. In conclusion, the inclusion of dietary ABGA up to 15% did not impair nutrient utilization and supported normal growth performance in C. catla fingerlings. However, higher inclusion levels may have a detrimental effect on their growth, nutrient utilization, and physio-metabolic responses.

Enhancing low-dose radiotherapy efficacy with PARP inhibitors via FBL-mediated oxidative stress response in colorectal cancer

Enhancing low-dose radiotherapy efficacy with PARP inhibitors via FBL-mediated oxidative stress response in colorectal cancer

Dynamic mRNA Stability Buffer Transcriptional Activation During Neuronal Differentiation and Is Regulated by SAMD4A.

Neurons are exceptionally sensitive to oxidative stress, which is the basis for many neurodegenerative disease pathophysiologies. The posttranscriptional basis for neuronal differentiation and behavior is not well characterized. The steady-state levels of mRNA are outcomes of an interplay between RNA transcription and decay. However, the correlation between mRNA transcription, translation, and stability remains elusive. We utilized a SH-SY5Y-based neural differentiation model that is widely used to study neurodegenerative diseases. After neuronal differentiation, we observed enhanced sensitivity of mature neurons to mitochondrial stresses and ferroptosis induction. We employed a newly developed simplified mRNA stability profiling technique to explore the role of mRNA stability in SH-SY5Y neuronal differentiation model. Transcriptome-wide mRNA stability analysis revealed neural-specific RNA stability kinetics. Our analysis revealed that mRNA stability could either exert the buffering effect on gene products or change in the same direction as transcription. Importantly, we observed that changes in mRNA stability corrected over or under transcription of mRNAs to maintain mRNA translation dynamics. Furthermore, we conducted integrative analysis of our mRNA stability data set, and a published CRISPR-i screen focused on neuronal oxidative stress responses. Our analysis unveiled novel neuronal stress response genes that were not evident at the transcriptional or translational levels. SEPHS2 emerged as an important neuronal stress regulator based on this integrative analysis. Motif analysis unveiled SAMD4A as a major regulator of the dynamic changes in mRNA stability observed during differentiation. Knockdown of SAMD4A impaired neuronal differentiation and influenced the response to oxidative stress. Mechanistically, SAMD4A was found to alter the stability of several mRNAs. The novel insights into the interplay between mRNA stability and cellular behaviors provide a foundation for understanding neurodevelopmental processes and neurodegenerative disorders and highlight dynamic mRNA stability as an important layer of gene expression.

METTL3 accelerates staphylococcal protein A (SpA)-induced osteomyelitis progression by regulating m6A methylation-modified miR-320a

Osteomyelitis (OM) is an inflammatory disease of bone infection and destruction characterized by dysregulation of bone homeostasis. Staphylococcus aureus (SA) has been reported to be the most common pathogen causing infectious OM. Recent studies have demonstrated that N6-methyladenosine (m6A) regulators are associated with the development of OM. However, the molecular mechanism of m6A modifications in OM remains unclear. Here, we investigated the function of methyltransferase-like 3 (METTL3)-mediated m6A modification in OM development. In this study, human bone mesenchymal stem cells (hBMSCs) were treated with staphylococcal protein A (SpA), a vital virulence factor of SA, to construct cell models of OM. Firstly, we found that METTL3 was upregulated in OM patients and SpA-induced hBMSCs, and SpA treatment suppressed osteogenic differentiation and induced oxidative stress and inflammatory injury in hBMSCs. Functional experiments showed that METTL3 knockdown alleviated the inhibition of osteogenic differentiation and the promotion of oxidative stress and inflammation in SpA-treated hBMSCs. Furthermore, METTL3-mediated m6A modification upregulated miR-320a expression by promoting pri-miR-320a maturation, and the mitigating effects of METTL3 knockdown on SpA-mediated osteogenic differentiation, oxidative stress and inflammatory responses can be reversed by miR-320 mimic. In addition, we demonstrated that phosphatidylinositol-4, 5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) was a downstream target of miR-320a, upregulation of PIK3CA alleviated miR-320a-induced inhibition of osteogenic differentiation, and upregulation of oxidative stress and inflammatory responses during SpA infection. Finally, we found that silencing METTL3 alleviated OM development by regulating the miR-320a/PIK3CA axis. Taken together, our data demonstrated that the METTL3/m6A/miR-320a/PIK3CA axis regulated SpA-mediated osteogenic differentiation, oxidative stress, and inflammatory responses in OM, which may provide a new therapeutic strategy for OM patients.

Utilizing the apical-out enteroids in vitro model to investigate intestinal glucose transport, barrier function, oxidative stress, and inflammatory responses in broiler chickens

IntroductionConventional 2D intestinal epithelial cell lines have been widely used in investigating intestinal functions, yet with limitations in recapitulating the in vivo gut physiology of chickens. A recently established chicken enteroid model with apical-out nature and the presence of leukocyte components represents intestinal mucosal functions. The objectives of this study were to 1) evaluate basic gut nutrient transport and barrier functions in this model and 2) identify the model’s effectiveness in studying inflammation and oxidative stress responses.MethodsEnteroids were generated from individual villus units isolated from the small intestine of Cobb500 broiler embryos. Enteroid viability, morphology, and epithelial cell markers were monitored; barrier function was evaluated based on the permeability to fluorescein isothiocyanate–dextran (FD4) with or without EDTA and lipopolysaccharide (LPS) challenges; nutrient transport was evaluated by fluorescence-labeled glucose (2NBD-G) with or without transporter blockade; the oxidative status was indicated by reactive oxygen species (ROS). Inflammatory and oxidative challenges were induced by LPS and menadione treatment, respectively. Selected marker gene expressions, including tight junction proteins (CLDN-1, CLDN-2, ZO-1, and OCCL), epithelial cell markers (Lgr-5, LYZ, and MUC-2), cytokines (IL-1β, IL-6, IL-8, IL-10, TNF-α, and INF-γ), and antioxidant enzymes (Nrf-2, catalase, and SOD), were determined by using RT-qPCR. Data were analyzed by one-way ANOVA among treatment groups.ResultsEnteroid cell activity was stable from day (d) 2 to d 6 and declined at d 7. Epithelial cell marker and cytokine expressions were stable from d 4 to d 6. FD4 permeability was increased after the EDTA treatment (P ≤ 0.05). Transporter-mediated 2NBD-G absorption was observed, which was reduced with glucose transporter blockade (P ≤ 0.05). Enteroids showed classic responses to LPS challenges, including upregulated gene expressions of IL-1β and IL-6, downregulated gene expressions of ZO-1 and OCCL, and increased FD4 permeability (P ≤ 0.05). Enteroids showed increased ROS generation (P ≤ 0.05) in response to oxidative stress.DiscussionIn conclusion, this apical-out enteroid model is a stable alternative in vitro model that exhibits intestinal barrier, nutrient transport, oxidation, and inflammation functions. With this enteroid model, we developed two challenge protocols for evaluating intestinal functions under oxidative stress and inflammation conditions.

Evolution of light-dependent functions of GIGANTEA.

GIGANTEA is a multifaceted plant-specific protein that originated in a streptophyte ancestor. The current known functions of GI include circadian clock control, light signalling, flowering time regulation, stomata response, chloroplast biogenesis, accumulation of anthocyanin, chlorophyll, and starch, phytohormone signalling, senescence and response to drought, salt, and oxidative stress. Six decades since its discovery, no functional domains have been defined, and its mechanism of action is still not well-characterised. In this review, we explore the functional evolution of GI to distinguish between ancestral and more recently acquired roles. GI integrated itself into various existing signalling pathways of the circadian clock, blue light, photoperiod, and osmotic and oxidative stress response. It also evolved parallelly to acquire new functions for chloroplast accumulation, red light signalling and anthocyanin production. In this review, we have encapsulated the known mechanisms of various biological functions of GI. Additionally, this manuscript will throw light on the evolution of GI in plant lineage.

E-cigarettes and vaping, new spotlight on smoking as an old cardiovascular risk factor?

Smoking is one of the leading causes of chronic non-communicable diseases and asignificant risk factor for cardiovascular and respiratory diseases. While global tobacco consumption has decreased over the past two decades, the use of e‑cigarettes and water pipes (shisha) has surged at an alarming rate, particularly among younger individuals. E‑cigarettes do not offer acompletely risk-free alternative to traditional cigarettes, as the vast array of flavors and ease of use contribute to agrowing number of dependent users. Furthermore, they are not necessarily effective in overcoming nicotine addiction. This contribution provides an overview of the cardiovascular health impacts associated with shisha smoking and e‑cigarette vaping, with aparticular emphasis on the detrimental effects on endothelial function. The harmful biological effects of the toxic substances in these products, especially oxidative stress and inflammatory responses, are also discussed. Finally, the current state of recommendations, legal regulations, and commercial advertising are summarized.

SntB triggers the antioxidant pathways to regulate development and aflatoxin biosynthesis in Aspergillus flavus.

The epigenetic reader SntB was identified as an important transcriptional regulator of growth, development, and secondary metabolite synthesis in Aspergillus flavus. However, the underlying molecular mechanism is still unclear. In this study, by gene deletion and complementation, we found SntB is essential for mycelia growth, conidial production, sclerotia formation, aflatoxin synthesis, and host colonization. Chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing (RNA-seq) analysis revealed that SntB played key roles in oxidative stress response of A. flavus, influencing related gene activity, especially catC encoding catalase. SntB regulated the expression activity of catC with or without oxidative stress, and was related to the expression level of the secretory lipase (G4B84_008359). The deletion of catC showed that CatC participated in the regulation of fungal morphogenesis, reactive oxygen species (ROS) level, and aflatoxin production, and that CatC significantly regulated fungal sensitive reaction and AFB1 yield under oxidative stress. Our study revealed the potential machinery that SntB regulated fungal morphogenesis, mycotoxin anabolism, and fungal virulence through the axle of from H3K36me3 modification to fungal virulence and mycotoxin biosynthesis. The results of this study shed light into the SntB-mediated transcript regulation pathways of fungal mycotoxin anabolism and virulence, which provided potential strategy to control the contamination of A. flavus and its aflatoxins.

Integrative Analyses of Genes of Pediatric Non-alcoholic Fatty Liver Disease Associated with Energy Metabolism.

Pediatric non-alcoholic fatty liver disease (NAFLD) is a chronic steatosis of the liver associated with energy metabolism in children and adolescents, failure to intervene promptly can elevate the risk of developing hepatocellular carcinoma. Therefore, this study aimed to understand the underlying mechanism of pediatric NAFLD and investigate potential biomarkers and therapeutic targets. We investigated genes using the GSE185051 data set related to energy metabolism from the GeneCards database, constructed protein-protein interaction network, identified hub genes and established networks representing interactions between these hub genes and miRNA, RNA-binding proteins, transcription factors, and drugs. Subsequently, we performed Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analysis, Gene Set Enrichment Analysis (GSEA), and immune infiltration analysis. Our analysis identified 9 hub genes through the PPI network. The target molecules were identified through the interaction network between hub genes and miRNAs, RNA-binding proteins, transcription factors, and drugs. GO analysis revealed that hub genes were associated with oxidative stress responses and other pathways. KEGG analysis highlighted their involvement in pathways such as insulin resistance, among others. GSEA revealed that hub genes were highly enriched in pathways related to Omega-9 fatty acid synthesis, among others. Immune infiltration analysis suggested that mast cells and T follicular helper cells play significant roles in the pathogenesis of NAFLD. We identified the hub genes in pediatric NAFLD closely related to energy metabolism. These findings offer the potential for identifying potential novel diagnostic biomarkers, and establishing therapeutic targets for pediatric NAFLD.

16S rRNA methyltransferase KsgA contributes to oxidative stress and antibiotic resistance in Pseudomonas aeruginosa

Ribosomal RNA (rRNA) modifications are involved in multiple biological processes. KsgA is a 16S rRNA adenine dimethyltransferase that methylates at the adenines 1518 and 1519 (A1518/1519) positions, which are located near the ribosome decoding center. These methylations are conserved and important for ribosome biogenesis and protein translation. In this study, we demonstrated the absence of A1518/1519 methylation in the 16S rRNA of a Pseudomonas aeruginosa ksgA mutant. Biolog phenotypic microarrays were used to screen the phenotypes of the ksgA mutant against various antimicrobial agents. The loss of ksgA led to increased sensitivity to menadione, a superoxide generator, which was, at least in part, attributed to decreased in a superoxide dismutase (SOD) activity. Interestingly, the decrease in SOD activity in the ksgA mutant was linked to a decrease in the SodM protein levels, but not the sodM mRNA levels. Furthermore, the ksgA mutant strain exhibited sensitivity to hygromycin B and tylosin antibiotics. The tylosin-sensitive phenotype was correlated with decreased transcriptional levels of tufA, tufB, and tsf, which encode elongation factors. Additionally, the ksgA mutant showed resistance to kasugamycin. Collectively, these findings highlight the role of KsgA in oxidative stress responses and antibiotic sensitivity in P. aeruginosa.

Bioenergetic shift and proteomic signature induced by lentiviral-transduction of GFP-based biosensors

Fluorescent proteins (FPs) stand as pivotal tools extensively employed across diverse biological research endeavors in various model systems. However, long-standing concerns surround their use due to the numerous side effects associated with their expression. Recent investigations have brought to light the significance of hydrogen peroxide (H2O2) that is associated with the maturation process of green fluorescent protein (GFP) fluorophores. The structural and functional impairments associated with GFP expression are possibly linked to this amount of H2O2. In this study, we assess the impact of the GFP-based HyPer7 biosensor on cellular homeostasis and proteome changes, aiming to identify potential risks related to oxidative stress responses that potentially risks the application of such tools. Cells expressing genome-integrated HyPer7 demonstrated altered mitochondrial membrane potential (MMP), which was alleviated by the addition of antioxidants or culturing cells at physiological normoxia (5 kPa O2). Additionally, HyPer7-expressing cells also exhibited significant impairment in mitochondrial oxidative respiration, suggesting broader mitochondrial dysfunction. Through untargeted proteomics analysis, we identified 26 proteins exhibiting differential expression in HyPer7-expressing cells compared to respective control cells. Functional annotation analysis showed that the list of the delineated proteins is associated with cellular responses to stress and the regulation of antioxidant mechanisms. Our findings underscore the significance of caution and validation in ensuring a thorough comprehension of cellular responses when using fluorescent protein-based tools, thereby enhancing the reliability of the results.

Magnesium-Doped Carbon Quantum Dot Nanomaterials Alleviate Salt Stress in Rice by Scavenging Reactive Oxygen Species to Increase Photosynthesis.

Salt stress has strongly impacted the long-term growth of eco-friendly farming worldwide. By targeting the oxidative stress induced by salt, the utilization of biomass-derived carbon dots (CDs) that possess high-efficiency antioxidant properties, are nontoxic, and have excellent biocompatibility represents a viable and effective approach for enhancing the salt tolerance of plants. In this study, we blended magnesium oxide nanoparticles with carbon sources derived from durian shells to construct Mg-doped carbon dots (Mg-CDs) through a hydrothermal reaction. We demonstrated that the foliar application of 150 μg/mL Mg-CDs to rice plants after treatment with 100 mM salt effectively increased the plant height (9.52%), fresh weight (22.41%), dry weight (33.33%), K+ content (21.46%), chlorophyll content (36.21%), and carotenoid content (16.21%); decreased the malondialdehyde (MDA) (9.43%), Na+ (25.75%), H2O2 (17.50%), and O2•- contents (37.99%); and promoted the photosynthetic system and antioxidant activity. Transcriptome analysis revealed that Mg-CD pretreatment triggered transcriptional reprogramming in rice seedlings. The enrichment analysis of the Kyoto Encyclopedia of Genes and Genomes pathways based on trend groups of gene expression patterns of Profile 8 and Profile 15 indicated that priming with Mg-CDs activated stress signaling- and defense-related pathways, such as metabolic pathways, biosynthesis of secondary metabolites, and photosynthesis pathways. These activations subsequently prompted the expression of genes related to the mitogen-activated protein kinase signaling pathway, hormone signal transduction, the oxidative stress response, and the photosynthetic system. This study demonstrated that the use of Mg-CDs represents a potential strategy to increase plant salt tolerance, creating the possibility for the regulation of crop salinity stress and offering valuable advancements in sustainable agriculture.