Integral Membrane Research Articles

Cryopreservation of goat spermatozoa in the Mekong Delta region of Vietnam: evaluating cryoprotectant effectiveness

Conserving and improving the quality of breeds is crucial for enhancing small ruminant production in Vietnam. To support this purpose, cryopreservation was offered as a promising method for semen preservation and maintaining genetic diversity. Moreover, many small-scale farmers in Mekong Delta rely on goats for both income and nutrition, making them an important part of farming activities. This study aimed to develop a sperm cryopreservation protocol and identify the optimal cryoprotectant for goat sperm in the Mekong Delta region of Vietnam. Semen samples were diluted with TCG-EggYolk freezing medium containing cryoprotectant agent (CPA) in a 1:1 ratio. The samples were then placed in 0.5 mL French straws, cooled to 15 °C and 5 °C, and subjected to nitrogen vapor before being immersed in liquid nitrogen at -196 °C. Experiment 1 utilized Glycerol as the CPA in concentrations of 0 %, 5 %, 8 %, and 11 %. Experiment 2 employed dimethyl sulfoxide (DMSO) as the CPA with the same concentrations. Thawed samples were evaluated for sperm quality. Results indicated that in Experiment 1, increasing the Glycerol concentration improved the overall motility, viability, and membrane integrity of sperm. The best outcomes were achieved with 8 % Glycerol, resulting in progressive motility of 57.5 % (P<0.05). In Experiment 2, the extender containing 8 % DMSO demonstrated significantly better performance in terms of overall motility, viability, and membrane integrity compared to 5 % or 11 % DMSO. Progressive motility was 53.5 % (P<0.05). In conclusion, the study determined that using 8 % Glycerol or 8 % DMSO is the optimal choice for freezing goat sperm in the Mekong Delta region of Vietnam.

FBLN2 is associated with basal cell markers Krt14 and ITGB1 in mouse mammary epithelial cells and has a preferential expression in molecular subtypes of human breast cancer.

Fibulin-2 (FBLN2) is a secreted extracellular matrix (ECM) glycoprotein and has been identified in the mouse mammary gland, in cap cells of terminal end buds (TEBs) during puberty, and around myoepithelial cells during early pregnancy. It is required for basement membrane (BM) integrity in mammary epithelium, and its loss has been associated with human breast cancer invasion. Herein, we attempted to confirm the relevance of FBLN2 to myoepithelial phenotype in mammary epithelium and to assess its expression in molecular subtypes of human breast cancer. The relationship between FBLN2 expression and epithelial markers was investigated in pubertal mouse mammary glands and the EpH4 mouse mammary epithelial cell line using immunohistochemistry, immunocytochemistry, and immunoblotting. Human breast cancer mRNA data from the METABRIC and TCGA datasets from Bioportal were analyzed to assess the association of Fbln2 expression with epithelial markers, and with molecular subtypes. Survival curves were generated using data from the METABRIC dataset and the KM databases. FBLN2 knockdown in mouse mammary epithelial cells was associated with a reduction in KRT14 and an increase in KRT18. Further, TGFβ3 treatment resulted in the upregulation of FBLN2 in vitro. Meta-analyses of human breast cancer datasets from Bioportal showed a higher expression of Fbln2 mRNA in claudin-low, LumA, and normal-like breast cancers compared to LumB, Her2 +, and Basal-like subgroups. Fbln2 mRNA levels were positively associated with mesenchymal markers, myoepithelial markers, and markers of epithelial-mesenchymal transition. Higher expression of Fbln2 mRNA was associated with better prognosis in less advanced breast cancer and this pattern was reversed in more advanced lesions. With further validation, these observations may offer a molecular prognostic tool for human breast cancer for more personalized therapeutic approaches.

Safety of low-intensity extracorporeal shock wave therapy in prostate disorders: in vitro and in vivo evidence.

Recent evidence suggests that low-intensity extracorporeal shock wave therapy (Li-ESWT) is a promising treatment for chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS); however, its safety in pelvic organs, particularly prostate tissues and cells, remains unclear. The current study evaluates the risks of prostate cell damage or oncogenesis following the administration of Li-ESWT for prostatitis. To this end, a robust in vitro model (Cell Counting Kit-8 [CCK-8] assay, clone formation assay, cell scratch assay, lactate dehydrogenase [LDH] release assay, flow cytometry, and immunoblotting assay) was designed to examine the effects of Li-ESWT on cell proliferation, clonogenicity, migration, membrane integrity, and DNA damage. Exome sequencing of Li-ESWT-treated cells was performed to determine the risk of carcinogenesis. Furthermore, an in vivo rat model (n = 20) was employed to assess the effects of Li-ESWT on cancer biomarkers (carcinoembryonic antigen [CEA], Ki67, proliferating cell nuclear antigen [PCNA], and gamma-H2A histone family member X, phosphorylation of the H2AX Ser-139 [γ-H2AX]) in prostate tissue. Based on our findings, Li-ESWT promotes cellular growth and motility without inducing significant cell membrane or DNA damage or alterations. Genetic analyses did not demonstrate an increase in mutations, and no damage to prostate tissue or upregulation of cancer biomarkers was detected in vivo. This comprehensive in vitro and in vivo assessment confirms the safety of Li-ESWT in managing prostate disorders.

Preparation of thermally conductive polyimide/aluminum oxide/boehmite composite separators for enhancing lithium‐ion battery safety and performance

AbstractThis study endeavors to enhance the safety of lithium‐ion batteries (LIBs) by synthesizing a polyamide acid (PAA)/Al2O3 composite spinning solution using 4,4′‐diaminodiphenyl ether (ODA) and pyromellitic anhydride (PMDA) as monomers, and nano‐Al2O3 as a thermal conductivity filler. Subsequently, the PAA/Al2O3 fiber membrane is fabricated via electrostatic spinning, followed by gradient heating imidization to produce a polyimide (PI)/Al2O3 composite membrane. This membrane is then dipped into a boron nitride (BM) slurry to ultimately yield an organic–inorganic PI/Al2O3/BM composite separator with superior flame‐retardant and thermal conductivity properties. The thermal stability, flame retardancy, electrolyte wettability, mechanical integrity, and cycle rate performance of the composite membranes are rigorously evaluated. The results demonstrate that the PI/5% Al2O3/BM composite membrane exhibits the most favorable overall performance, with no shrinkage observed at 200°C and no significant changes after sustained ignition for 10 s. The incorporation of the thermal conductivity Al2O3 filler significantly enhances the heat transfer properties of the composite separator. The room temperature ionic conductivity reaches 2.786 mS cm−1 after electrolyte absorption, and the initial discharge capacity of the assembled battery is 156.28 mAhg−1. Following 100 charge/discharge cycles at 0.2C, the capacity retention rate is 97.7%, and at a discharge rate of 5C, the capacity retention rate is 74.9%.

Leaf Membrane Stability under High Temperatures as an Indicator of Heat Tolerance in Potatoes and Genome-Wide Association Studies to Understand the Underlying Genetics

High temperatures during the crop growing season are becoming more frequent and unpredictable, resulting in reduced crop productivity and quality. Heat stress disrupts plant metabolic processes that affect cell membrane composition and integrity. Cell membrane permeability, ion leakage, and heat shock proteins have been evaluated to screen for heat tolerance in plants. In potatoes, it is unclear whether leaf membrane stability under heat stress is correlated with underground tuber productivity and quality. The main goal of this study was to evaluate if leaf membrane relative electrolyte conductivity (REC) under high temperatures could be used to identify heat-tolerant potato genotypes. Electrolyte leakage assays, correlation estimations, and genome-wide association studies were carried out in 215 genotypes. Expression levels of small heat shock protein 18 (sHSP18) were evaluated in the heat-sensitive potato variety Russet Burbank and compared with those of the heat-tolerant variety Vanguard Russet using Western blotting. Significant differences were observed among genotypes for leaf membrane REC under extreme heat (50°C); REC values ranged from 47.0–99.5%. Leaf membrane REC was positively correlated with tuber external and internal defects and negatively correlated with yield. REC was negatively correlated with the content of several tuber minerals, such as nitrogen, magnesium, and manganese. Eleven quantitative trait loci (QTLs) were identified for leaf membrane REC, explaining up to 13.8% of the phenotypic variance. Gene annotation in QTL areas indicated associations with genes controlling membrane solute transport and plant responses to abiotic stresses. Vanguard Russet had lower leaf REC and higher expression of sHSP18 under high-temperature stress. Our findings indicate that leaf membrane REC under high temperatures can be used as an indicator of potato heat tolerance.

Docosahexaenoic acid (DHA) alleviates inflammation and damage induced by experimental colitis.

Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), are chronic gastrointestinal disorders associated with significant morbidity and complications. This study investigates the therapeutic potential of docosahexaenoic acid (DHA) in a trinitrobenzene sulfonic acid (TNBS) induced colitis model, focusing on inflammation, oxidative stress, and intestinal membrane permeability. Wistar albino rats were divided into Control, Colitis, and Colitis + DHA groups (n = 8-10/group). The Colitis and Colitis + DHA groups received TNBS intrarectally, while the Control group received saline. DHA (600 mg/kg/day) or saline was administered via gavage for six weeks. Macroscopic and microscopic evaluations of colon tissues were conducted. Parameters including occludin and ZO-1 expressions, myeloperoxidase (MPO) activity, malondialdehyde (MDA), glutathione (GSH), total antioxidant status (TAS), total oxidant status (TOS), Interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) levels were measured in colon tissues. Colitis induction led to significantly higher macroscopic and microscopic damage scores, elevated TOS levels, reduced occludin and ZO-1 intensity, decreased mucosal thickness, and TAS levels compared to the Control group (p < 0.001). DHA administration significantly ameliorated these parameters (p < 0.001). MPO, MDA, TNF-α, and IL-6 levels were elevated in the Colitis group but significantly reduced in the DHA-treated group (p < 0.001 for MPO, MDA; p < 0.05 for TNF-α and IL-6). DHA demonstrated antioxidant and anti-inflammatory effects by reducing reactive oxygen species production, enhancing TAS capacity, preserving GSH content, decreasing proinflammatory cytokine levels, preventing neutrophil infiltration, reducing shedding in colon epithelium, and improving gland structure and mucosal membrane integrity. DHA also upregulated the expressions of occludin and ZO-1, critical for barrier function. Thus, DHA administration may offer a therapeutic strategy or supplement to mitigate colitis-induced adverse effects.

Methoxy Chalcone Derivatives: Promising Antimicrobial Agents Against Phytopathogens.

Chalcone (E)-1,3-diphenyl-prop-2-en-1-one and a series of 14 methoxylated derivatives have been synthesized via Claisen-Schmidt aldol condensation and characterized by FTIR, CG/MS/DIC, 1D (1H and 13C), 2D (COSY, HSQC, and HMBC) NMR, and EMAR techniques. All molecules were tested at 1mM concentration for antifungal (Sclerotium sp., Macrophomina phaesolina and Colletotrichum gloeosporioides), antibacterial (Acidovorax citrulli two strains), and antiprotozoal (Phytomonas serpens) activities. Unmodified chalcone (CH0) and derivatives CH1, CH2, CH8 stood out in terms of antifungal activity. CH0 presented IC50 values of 47.3 µM (9.8 µg/mL) for the fungus C. gloeosporioides. In addition, fluorescence microscopy indicated that CH0 promoted loss of hyphal cell membrane integrity. The CH1 and CH2 derivatives promoted the inhibition of Sclerotium sp. with IC50 of 127.5 µM (32.9 µg/mL) and 110.4 µM (29.6 µg/mL), respectively. All molecules showed high activity against the phytoparasite P. serpens with IC50 values of 0.98, 2.40, 10.25, and 3.11 µM for the derivatives CH2, CH3, CH5 and CH14 respectively. The results demonstrated that derivatives methoxylated in both rings (CH2) as well as derivatives with a furan ring associated with the methoxy group in ring A, as well as unmodified chalcone can be promising agricultural fungicides for controlling the fungi studied.

Abscisic acid treatment positively regulates suberin polyaliphatics biosynthesis at wound sites in postharvest yam tubers

Suberin polyaliphatics (SPA) accumulation on the closing layer plays a significant role in wound healing of fruit and vegetables. However, no literature is available on abscisic acid (ABA) effect on yam tuber healing in relation to SPA biosynthesis. In this study, ABA treatment decreased weight loss and disease incidence of yam tubers, maintained the integrity of cell membrane, and promoted the accumulation and polymerization of SPA monomers such as fatty acids (FAs), ω-hydroxyacid (ω-OHA) and α, ω-dicarboxylic acid (α, ω-diA). Gene expression of β-ketoacyl CoA synthases (DoKCS2, DoKCS6), cytochrome P450 fatty acid ω-hydroxylases (DoCYP86A1, DoCYP94B3), Glycerol-3-phosphate acyltransferases (DoDPAT5, DoGPAT7) and feruloyl-CoA transferase (DoFHT), which were associated with the biosynthesis of SPA monomers, were enhanced by ABA treatment. ABA improved gene expression of ATP-binding cassette transporters (DoABCG2, DoABCG6) and GDSL-type esterase/lipases (DoGELP38, DoGELP51, DoGELP96), which might facilitate the transport and polymerization of SPA monomers. Contrarily, applied fluridone (FLD, an inhibitor of ABA biosynthesis) exhibited an opposite effect to ABA treatment. The results indicate that ABA accelerates yam tuber healing via positively regulating SPA biosynthesis.

Inhibitory activity and antioomycete mechanism of citral against Phytophthora capsici

The natural terpenoid citral has antifungal activity against multiple fungi, but its bioactivity against oomycetes is unclear. Therefore, this study investigated the antioomycete activity and mechanism of citral against Phytophthora capsici, a highly destructive invasive oomycete. Results showed that citral not only had a great inhibition on the mycelial growth of P. capsici (EC50 = 94.15 mg/L), but also had a significant inhibition on multiple spores, such as sporangia formation, zoospore discharge and zoospore germination. Citral at 4000 mg/L exhibited favorable protective (73.33%) and curative efficacy (55.11%) against pepper Phytophthora blight. Citral significantly damaged the hyphal morphology, disrupted the cell membrane integrity, increased the permeability of cell membrane, and increased the glycerol content in P. capsici. A total of 250 upregulated and 288 downregulated proteins were identified in iTRAQ-based quantitative proteomic analysis. Downregulated proteins were mostly enriched in pathways of ABC transporters, cyanoamino acid metabolism and starch and sucrose metabolism, suggesting an inhibition of citral on transmembrane transporter (e.g., ABC transporters) and pathogenicity (e.g., β-glucosidases) proteins. Upregulated proteins were enriched in biosynthesis of unsaturated fatty acids, pyruvate metabolism and glycolysis/gluconeogenesis, suggesting an activation of citral on energy generation proteins, including acyl-CoA oxidase, D-lactate dehydrogenase, pyruvate kinase, acetyl-CoA synthetase and phosphoenolpyruvate carboxykinase. Biochemical and iTRAQ analysis suggested that cell membrane may be the target of citral in P. capsici.

Effect of tyrode albumin lactate pyruvate and modified Krebs Ringers broth media on in vitro capacitation of HD-K75 boar spermatozoa at different period of incubation.

In vitro capacitation allows for a greater understanding of the mechanisms underlying fertilization and the development of improved reproductive techniques for improving fertility rates in porcine. Tyrodes albumin lactate pyruvate (TALP) and modified Krebs Ringers Broth (m-KRB) are two medias that are commonly used in research experiments to induce capacitation in boar spermatozoa (Cañón-Beltrán etal., Theriogenology, 198, 2023 and 231; Oberlender etal., Archivos de Medicina Veterinaria, 44, 2012 and 201; Sahoo etal., International Journal of Biological Macromolecules, 241, 2023 and 124502). Moreover, understanding the morphological and functional changes in boar spermatozoa at different hours of capacitation periods might aid in the development of novel techniques for improving sperm quality and increasing the litter size. This study was carried out to investigate the effect of Tyrode albumin lactate pyruvate and modified Krebs Ringers Broth media on invitro capacitation of HD-K75 boar spermatozoa at three different periods of incubation. A total of 24 ejaculate from four clinically healthy, 10-12 months aged HD-K75 boars, maintained at ICAR-All India Coordinated Research Project (AICRP) on pig were selected. Semen was collected by 'Simple fist' method using a portable dummy. The semen samples having 200 mL volume, 103 × 106 spermatozoa/ml concentration and 70% initial motility were selected and split into two parts and suspended in TALP and m-KRB media, respectively, and incubated for 5 h at 37°C. Seminal parameters viz. sperm viability, plasma membrane integrity and acrosomal integrity were estimated in the samples at 0, 3 and 5 h of incubation. This study revealed that there was significant variation between media in live acrosome-reacted (p < .05) and HOST-reacted (p < .01) spermatozoa, while between capacitation periods significant (p < .01) variation was observed in hyperactivated spermatozoa, live acrosome-reacted spermatozoa, HOST-reacted spermatozoa, FITC-labelled PSA, extracellular protein and sperm cholesterol. Non-significant variation was observed in total phospholipid. TALP showed overall better consequence on sperm viability, plasma membrane and acrosomal integrity of boar spermatozoa. From this study, it could be concluded that both TALP and m-KRB media were virtuous to induce capacitation in HD-K75 boar spermatozoa. TALP media, however, had a better effect on sperm viability, plasma membrane and acrosomal integrity of boar spermatozoa. Out of the three different periods, 3 h capacitation period resulted in significantly (p < .01) higher incidence of sperm viability, plasma membrane and acrosomal integrity in HD-K75 boar spermatozoa.

Cytokinin oxidase2-deficient mutants improve panicle and grain architecture through cytokinin accumulation and enhance drought tolerance in indica rice.

The Osckx2 mutant accumulates cytokinin thereby enhancing panicle branching, grain yield, and drought tolerance, marked by improved survival rate, membrane integrity, and photosynthetic function. Cytokinins (CKs) are multifaceted hormones that regulate growth, development, and stress responses in plants. Cytokinins have been implicated in improved panicle architecture and grain yield; however, they are inactivated by the enzyme cytokinin oxidase (CKX). In this study, we developed a cytokinin oxidase 2 (Osckx2)-deficient mutant using CRISPR/Cas9 gene editing in indica rice and assessed its function under water-deficit and salinity conditions. Loss of OsCKX2 function increased grain number, secondary panicle branching, and overall grain yield through improved cytokinin content in the panicle tissue. Under drought conditions, the Osckx2 mutant conserved more water and demonstrated improved water-saving traits. Through reduced transpiration, Osckx2 mutants showed an improved survival response than the wild type to unset dehydration stress. Further, Osckx2 maintained chloroplast and membrane integrity and showed significantly improved photosynthetic function under drought conditions through enhanced antioxidant protection systems. The OsCKX2 function negatively affects panicle grain number and drought tolerance, with no discernible impact in response to salinity. The finding suggests the utility of the beneficial Osckx2 allele in breeding to develop climate-resilient, high-yielding cultivars for future food security.

Intracellularly Synthesized Artificial Exosome Treats Acute Lung Injury.

Acute lung injury (ALI) and its severe form, acute respiratory distress syndrome (ARDS), induce high morbidity and mortality rates, which challenge the present approaches for the treatment of ALI/ARDS. The clinically used photosensitizer verteporfin (VER) exhibits great potential in the treatment of acute lung injury and acute respiratory distress syndrome (ALI/ARDS) by regulating macrophage polarization and reducing inflammation. Nevertheless, its hydrophobic characteristics, nonspecificity, and constrained bioavailability hinder its therapeutic efficacy. In this work, we developed a type of VER-cored artificial exosome (EVM), which was produced by using mesoporous silica nanoparticles (MSNs) to load VER, followed by the exocytosis of internalized VER-MSNs from mouse bone marrow-derived mesenchymal stem cells (mBMSCs) without further modification. Both in vitro and in vivo assessments confirmed the powerful anti-inflammation induced by EVM. EVM also showed significant higher accumulation to inflammatory lungs compared with healthy ones, which was beneficial to the treatment of ALI/ARDS. EVM improved pulmonary function, attenuated lung injury, and reduced mortality in ALI mice with high levels of biocompatibility, exhibiting a 5-fold higher survival rate than the control. This type of artificial exosome emitted near-infrared light in the presence of laser activation, which endowed EVM with trackable ability both in vitro and in vivo. Our work developed a type of clinically used photosensitizer-loaded artificial exosome with membrane integrity and traceability. To the best of our knowledge, this kind of intracellularly synthesized artificial exosome was developed and showed great potential in ALI/ARDS therapy.

Plant Adaptation and Tolerance to Heat Stress: Advance Approaches and Future Aspects.

Heat stress impacts plant growth at all phases of development, although the particular threshold for heat tolerance varies significantly across different developmental stages. During seed germination, elevated temperatures can either impede or completely halt the process, contingent upon the plant type and the severity of the stress. During advanced stages, high temperatures can have a negative impact on photosynthesis, respiration, water balance, and membrane integrity. Additionally, they can also influence the levels of hormones and primary and secondary metabolites. In addition, during the growth and development of plants, there is an increased expression of various heat shock proteins, as well as other proteins related to stress, and the generation of reactive oxygen species (ROS). These are significant plant responses to heat stress. Plants employ several strategies to deal with heat stress, such as maintaining the stability of their cell membranes, removing harmful reactive oxygen species (ROS), producing antioxidants, accumulating and adjusting compatible solutes, activating mitogen-activated protein kinase (MAPK) and calcium-dependent protein kinase (CDPK) cascades, and, crucially, signaling through chaperones and activating transcription. These molecular-level systems boost the ability of plants to flourish in heat stress. Potential genetic methods to enhance plant heat stress resistance encompass old and modern molecular breeding techniques and transgenic approaches, all of which rely on a comprehensive comprehension of these systems. Although several plants exhibit enhanced heat tolerance through traditional breeding methods, the effectiveness of genetic transformation techniques has been somewhat restricted. The latter results from the current constraints in our understanding and access to genes that have known impacts on plant heat stress tolerance. However, these challenges may be overcome in the future. Besides genetic methods, crops' heat tolerance can be improved through the pre-treatment of plants with various environmental challenges or the external application of osmoprotectants such as glycine betaine and proline. Thermotolerance is achieved through an active process in which plants allocate significant energy to maintain their structure and function to avoid damage induced by heat stress. The practice of nanoparticles has been shown to upgrade both the standard and the quantity of produce when crops are under heat stress. This review provides information on the effects of heat stress on plants and explores the importance of nanoparticles, transgenics, and genomic techniques in reducing the negative consequences of heat stress. Furthermore, it explores how plants might adapt to heat stress by modifying their biochemical, physiological, and molecular reactions.

SLC25A48 controls mitochondrial choline import and metabolism.

Choline is an essential nutrient for the biosynthesis of phospholipids, neurotransmitters, and one-carbon metabolism with a critical step being its import into mitochondria. However, the underlying mechanisms and biological significance remain poorly understood. Here, we report that SLC25A48, a previously uncharacterized mitochondrial inner-membrane carrier protein, controls mitochondrial choline transport and the synthesis of choline-derived methyl donors. We found that SLC25A48 was required for brownfat thermogenesis, mitochondrial respiration, and mitochondrial membrane integrity. Choline uptake into the mitochondrial matrix via SLC25A48 facilitated the synthesis of betaine and purine nucleotides, whereas loss of SLC25A48 resulted in increased production of mitochondrial reactive oxygenspecies and imbalanced mitochondrial lipids. Notably, human cells carrying a single nucleotide polymorphism on the SLC25A48 gene and cancer cells lacking SLC25A48 exhibited decreased mitochondrialcholine import, increased oxidative stress, and impaired cell proliferation. Together, this study demonstrates that SLC25A48 regulates mitochondrial choline catabolism, bioenergetics, and cell survival.

The cytoprotective effect of Gymnema inodorum leaf extract against hypoxia-induced cardiomyocytes injury

Ischemic heart disease stands out as a major global contributor to mortality, with the initiation of hypoxia, marked by reduced oxygen availability, disrupting the balance of reactive oxygen species (ROS), leading to cellular injury. Exploring antioxidants derived from medicinal plants is becoming more interesting as a potential alternative treatment, especially for mitigating myocardial injury. Thus, this study aimed to assess the cytoprotective efficacy of Gymnema inodorum leaf extract (GIE) in a rat cardiac myoblast, H9c2, subjected to an in vitro hypoxia. The cell viability, intracellular ROS production and the expression of inflammatory cytokines were quantified, and hypoxia-induced cell morphology changes were observed using confocal fluorescence microscopy. The results showed that GIE notably enhanced cell viability, preserving membrane integrity, when compared with the hypoxic group. Remarkably, GIE significantly reduced hypoxia-induced intracellular ROS production, attributable to its inherent antioxidant properties. Furthermore, GIE significantly reduced interleukin (IL)-1β, interleukin (IL)-6 mRNA expression level and tended to reduce tumor necrosis factor-α (TNF-α) mRNA expression. In conclusion, these findings underscore the potential of GIE in mitigating hypoxia-induced myocardial injury, highlighting its robust antioxidant and anti-inflammatory attributes.

Antibacterial mechanism of the methanol extract of Thamnolia subuliformis (Ehrh.) W. Culb against Staphylococcus aureus.

Thamnolia subuliformis (Ehrh.) W. Culb. is a species of lichen with edible and medicinal applications in China. Our previous studies demonstrated that the methanol extract of Thamnolia subuliformis (METS) exhibits broad antibacterial activity and stability against foodborne pathogens. This study aimed to investigate the antibacterial mechanism of METS against Staphylococcus aureus using nontargeted metabolomics, focusing on cell wall and membrane damage. The results revealed that the minimum inhibitory concentration (MIC) was 0.625mg·mL-1 and that METS had good biosafety at this concentration. METS caused significant damage to the cell wall and membrane integrity, based on both morphological observation by electron microscopy and the leakage of alkaline phosphatase, protein, and nucleic acid in the cell cultures. Treatment with METS at the MIC disrupted the lipid metabolism of S. aureus, causing a decrease in the metabolism of various phospholipids and sphingolipids in the cell membrane and an increase in the ratio of saturated fatty acids to unsaturated fatty acids. Moreover, it influenced intracellular amino acid and energy metabolism. These results shed light on the antibacterial mechanism of METS against S. aureus while also serving as a reference for the further development of natural antibacterial compounds derived from Thamnolia subuliformis.

Hesperidin alleviates terbuthylazine-induced ferroptosis via maintenance of mitochondria-associated endoplasmic reticulum membrane integrity in chicken hepatocytes

Terbuthylazine (TBA) is a common triazine herbicide used in agricultural production, which causes toxic damage in multiple tissues. Hesperidin (HSP) is a flavonoid derivative that has anti-inflammatory, antioxidant and cytoprotective effects, but its role in reducing toxic damage caused by pesticides is still unclear. In this study, we aimed to investigate the toxic effect of TBA exposure on chicken hepatocytes and the therapeutic effect of HSP on the TBA-induced hepatotoxicity. Our results demonstrated that HSP could alleviate TBA exposure-induced endoplasmic reticulum (ER) stress. Interestingly, TBA significantly disrupted the integrity of mitochondria-associated endoplasmic reticulum membrane (MAM), while HSP treatment showed the opposite tendency. In addition, TBA could significantly trigger ferroptosis in liver, and HSP treatment reversed ferroptosis under TBA exposure. These results suggested that HSP could inhibit ER stress and alleviate ferroptosis under TBA exposure via maintaining MAM integrity, which provided a novel strategy to take precautions against TBA toxicity.

The multifaceted role of TolA protein in promoting survival, biofilm formation and virulence of avian pathogenic Escherichia coli

Avian pathogenic Escherichia coli (APEC) can spread beyond the intestines and cause systemic infections, leading to various clinical manifestations, including airsacculitis, pericarditis, perihepatitis and colisepticemia. The mechanisms facilitating this extraintestinal infections are not fully understood. In this study, we investigate how the tolA gene affects APEC virulence by encoding a protein involved in maintaining outer membrane integrity. We constructed a tolA deletion mutant of APEC strain E058 and evaluated its growth and survival in various environments, including in vitro cultures and in vivo infection models in chickens. We found that the motility-defective ΔtolA mutant exhibits reduced biofilm formation ability and weakened resistance to the environmental stresses, suggesting an important role for TolA in APEC's survival. The lack of tolA gene affects the bacterial ability to resist the host's immune system, such as complement-mediated serum killing or phagocytosis, as shown by the serum killing and macrophage phagocytosis assays. Additionally, in vivo infection studies using chickens demonstrated that the ΔtolA mutant displayed attenuated virulence, evidenced by reduced mortality and lower tissue bacterial burden. Reverse transcription quantitative real-time PCR (RT-qPCR) analysis revealed that inactivation of tolA led to downregulation of virulence genes associated with serum resistance (traT) and flagellar biosynthesis (fliR). Taken together, our findings demonstrate the multifaceted role of TolA protein in promoting the survival, immune evasion, biofilm formation, and virulence of APEC E058. This suggests that targeting TolA could potentially offer new strategies for combating APEC infections.

Erg251 has complex and pleiotropic effects on sterol composition, azole susceptibility, filamentation, and stress response phenotypes.

Ergosterol is essential for fungal cell membrane integrity and growth, and numerous antifungal drugs target ergosterol. Inactivation or modification of ergosterol biosynthetic genes can lead to changes in antifungal drug susceptibility, filamentation and stress response. Here, we found that the ergosterol biosynthesis gene ERG251 is a hotspot for point mutations during adaptation to antifungal drug stress within two distinct genetic backgrounds of Candida albicans. Heterozygous point mutations led to single allele dysfunction of ERG251 and resulted in azole tolerance in both genetic backgrounds. This is the first known example of point mutations causing azole tolerance in C. albicans. Importantly, single allele dysfunction of ERG251 in combination with recurrent chromosome aneuploidies resulted in bona fide azole resistance. Homozygous deletions of ERG251 caused increased fitness in low concentrations of fluconazole and decreased fitness in rich medium, especially at low initial cell density. Homozygous deletions of ERG251 resulted in accumulation of ergosterol intermediates consistent with the fitness defect in rich medium. Dysfunction of ERG251, together with FLC exposure, resulted in decreased accumulation of the toxic sterol (14-ɑ-methylergosta-8,24(28)-dien-3β,6α-diol) and increased accumulation of non-toxic alternative sterols. The altered sterol composition of the ERG251 mutants had pleiotropic effects on transcription, filamentation, and stress responses including cell membrane, osmotic and oxidative stress. Interestingly, while dysfunction of ERG251 resulted in azole tolerance, it also led to transcriptional upregulation of ZRT2, a membrane-bound Zinc transporter, in the presence of FLC, and overexpression of ZRT2 is sufficient to increase azole tolerance in wild-type C. albicans. Finally, in a murine model of systemic infection, homozygous deletion of ERG251 resulted in decreased virulence while the heterozygous deletion mutants maintain their pathogenicity. Overall, this study demonstrates that single allele dysfunction of ERG251 is a recurrent and effective mechanism of acquired azole tolerance. We propose that altered sterol composition resulting from ERG251 dysfunction mediates azole tolerance as well as pleiotropic effects on stress response, filamentation and virulence.

Alzheimer's disease genetic pathways impact cerebrospinal fluid biomarkers and imaging endophenotypes in non-demented individuals.

Unraveling how Alzheimer's disease (AD) genetic risk is related to neuropathological heterogeneity, and whether this occurs through specific biological pathways, is a key step toward precision medicine. We computed pathway-specific genetic risk scores (GRSs) in non-demented individuals and investigated how AD risk variants predict cerebrospinal fluid (CSF) and imaging biomarkers reflecting AD pathology, cardiovascular, white matter integrity, and brain connectivity. CSF amyloidbeta and phosphorylated tau were related to most GRSs. Inflammatory pathways were associated with cerebrovascular disease, whereas quantitative measures of white matter lesion and microstructure integrity were predicted by clearance and migration pathways. Functional connectivity alterations were related to genetic variants involved in signal transduction and synaptic communication. This study reveals distinct genetic risk profiles in association with specific pathophysiological aspects in predementia stages of AD, unraveling the biological substrates of the heterogeneity of AD-associated endophenotypes and promoting a step forward in disease understanding and development of personalized therapies. Polygenic risk for Alzheimer's disease encompasses six biological pathways that can be quantified with pathway-specific genetic risk scores, and differentially relate to cerebrospinal fluid and imaging biomarkers. Inflammatory pathways are mostly related to cerebrovascular burden. White matter health is associated with pathways of clearance and membrane integrity, whereas functional connectivity measures are related to signal transduction and synaptic communication pathways.