Maintaining Cell Membrane Integrity Research Articles

Family Identification and Functional Study of Copper Transporter Genes in Pleurotus ostreatus

The copper transport (COPT/Ctr) family plays an important role in maintaining metal homeostasis in organisms, and many species rely on Ctrs to achieve transmembrane transport via copper (Cu) uptake. At present, the Ctr family is widely studied in plants. However, there are few reports on the use of Ctrs in edible mushrooms. In this study, the Pleurotus ostreatus CCMSSC00389 strain was used as the research object, and the addition of exogenous copper ions (Cu2+) increased the temperature tolerance of mycelia, maintained the integrity of cell membranes, and increased mycelial density. In addition, four PoCtr genes were further identified and subjected to bioinformatics analysis. Further research revealed that there were differences in the expression patterns of the PoCtr genes under different temperature stresses. In addition, the biological function of PoCtr4 was further explored by constructing transformed strains. The results showed that OE-PoCtr4 enhanced the tolerance of mycelia to heat stress and H2O2. After applying heat stress (40 °C), OE-PoCtr4 promoted the recovery of mycelia. Under mild stress (32 °C), OE-PoCtr4 promoted mycelial growth, maintained cell membrane integrity, and reduced the degree of cell membrane damage caused by heat stress. It is speculated that OE-PoCtr4 may maintain the integrity of the cell membrane and enhance the heat resistance of mycelia by regulating the homeostasis of Cu2+.

PlFabG improves high-temperature resistance in herbaceous peony by increasing saturated fatty acids

The herbaceous peony (Paeonia lactiflora Pall.) is renowned for its striking flowers, which are highly valued in the cut flower industry. However, in the middle and lower reaches of the Yangtze River, the elevated summer temperatures negatively affect the plant's flowering capacity in the subsequent year. 3-oxoacyl-ACP reductase (FabG) is a component of the type II fatty acid synthesis (FAS II) system, where it plays a role in facilitating the production of saturated fatty acids. However, its role in conferring resistance to high-temperature stress remains unclear. In order to investigate the function of PlFabG in dealing with high-temperature stress, we isolated PlFabG from P. lactiflora. The gene contains an open reading frame (ORF) of 780 bp, which encodes 259 amino acids. Quantitative real-time PCR (qRT-PCR) analysis showed that the expression levels of PlFabG increased with prolonged exposure to high temperature. Additionally, plants overexpressing PlFabG maintained a relatively healthy phenotype under high-temperature stress, whereas plants with silencing PlFabG exhibited more severe leaf scorching and wilting under the same conditions. Various physiological indices indicated that PlFabG reduced reactive oxygen species (ROS) accumulation and enhanced the saturation of photosystem II. Most importantly, PlFabG helped P. lactiflora withstand high-temperature stress by increasing the proportion of saturated fatty acids, thereby maintaining cell membrane integrity. These findings elucidate the beneficial role of PlFabG in enhancing plant tolerance to high temperature and provide a strong theoretical support for the development of high-temperature tolerance in transgenic P. lactiflora.

Huang-Pu-Tong-Qiao Formula Alleviates Hippocampal Neuron Damage by Inhibiting NLRP3 Inflammasome-mediated Pyroptosis in Alzheimer's Disease.

Huang-Pu-Tong-Qiao (HPTQ), a Traditional Chinese Medicine formula, has achieved remarkable efficacy in clinically treating Alzheimer's disease (AD). Pyroptosis refers to the inflammatory necrosis of cells, which contributes to AD pathological progression. However, it is unclear whether the therapeutic effect of HPTQ on AD is related to reducing pyroptosis. In this study, the network pharmacology analysis was used to predict the molecular mechanism of HPTQ in treating AD and validated our hypothesis through mice and cell experiments. APP/PS1 transgenic mice and Aβ25-35-injured HT22 cells were used as AD models in vivo and in vitro. The pharmacological effects and mechanisms of HPTQ on AD were evaluated by Morris water maze, Y-maze, transmission electron microscope, immunofluorescence, Hoechst/PI staining, western blot, and ELISA. Network pharmacology reveals the correlation between the therapeutic effect of HPTQ on AD and the NOD-like receptor signaling pathway. In APP/PS1 mice, HPTQ reduced the escape latency and maintained cell membrane integrity. In HT22 cells, 15% HPTQ-medicated serum and 10 µM MCC950 increased cell viability and decreased PI positive rate compared with the Model group. In addition, HPTQ treatment in AD animal and cell models reduced the protein expressions of NLRP3, ASC, cleaved caspase-1, GSDMD, GSDMD-N, IL-1β, and IL-18. The experimental results of MCC950 specifically inhibiting the NLRP3 expression suggested that HPTQ might reduce neuronal pyroptosis by reducing NLRP3 inflammasome. Network pharmacology and experimental validation suggested that HPTQ alleviated NLRP3 inflammasome-mediated neuronal pyroptosis in AD, which could provide valuable candidate drugs for AD clinical treatment.

Identification of genes related to fatty acid metabolism in type 2 diabetes mellitus

AimFatty acid metabolism is pivotal for lipid synthesis, cellular signaling, and maintaining cell membrane integrity. However, its diagnostic significance in type 2 diabetes mellitus (T2DM) remains unclear. Materials and methodsThree datasets and fatty acid metabolism-related genes were retrieved. Differential expression analysis, WGCNA, machine learning algorithms, diagnostic analysis, and validation were employed to identify key feature genes. Functional analysis, ceRNA network construction, immune microenvironment assessment, and drug prediction were conducted to explore the underlying molecular mechanisms. ResultsSix feature genes were identified with strong diagnostic performance and were involved in processes such as ribosome function and fatty acid metabolism. Immune cells, including dendritic cells, eosinophils, and neutrophils, may play a role in the progression of T2DM. ceRNA and drug-target network analysis revealed potential interactions, such as RP11-miR-29a-YTHDF3 and BPA-MSANTD1. The expression patterns of the feature genes, except for YTHDF3, were consistently upregulated in T2DM, aligning with trends observed in the training set. ConclusionThis study investigated the potential molecular mechanisms of six fatty acid metabolism-related genes in T2DM, offering valuable insights that may guide future research and therapeutic development.

Ca2+-dependent vesicular and non-vesicular lipid transfer controls hypoosmotic plasma membrane expansion.

Robust coordination of surface and volume changes is critical for cell integrity. Few studies have elucidated the plasma membrane (PM) remodeling events during cell surface and volume alteration, especially regarding PM sensing and its subsequent rearrangements. Here, using fission yeast protoplasts, we reveal a Ca2+-dependent mechanism for membrane addition that ensures PM integrity and allows its expansion during acute hypoosmotic cell swelling. We show that MscS-like mechanosensitive channels activated by PM tension control extracellular Ca2+ influx, which triggers direct lipid transfer at endoplasmic reticulum (ER)-PM contact sites by conserved extended-synaptotagmins and accelerates exocytosis, enabling PM expansion necessary for osmotic equilibrium. Defects in any of these key events result in rapid protoplast rupture upon severe hypotonic shock. Our numerical simulations of hypoosmotic expansion further propose a cellular strategy that combines instantaneous non-vesicular lipid transfer with bulk exocytic membrane delivery to maintain PM integrity for dramatic cell surface/volume adaptation.

Light emitting diodes for the improvement of postharvest quality of wild rocket in soilless and soil-bound cultivation systems

Wild rocket (Diplotaxis tenuifolia (L.) DC cv. Dallas) is a leafy green vegetable appreciated for its pungent taste and healthy properties, often consumed as a ready-to-eat product. The cultivation system is crucial in determining the overall quality, while postharvest storage is fundamental for preserving nutritional quality, phytochemicals, and vitamins. This study aimed to investigate the phytochemical content and microbiological quality of soilless (SS) and soil-bound (SB) wild rocket during cold postharvest storage under blue, red, and green Light Emitting Diode (LED). Blue LED increased chlorophylls and carotenoids in SB after two days of storage, and chlorophyll a in SS after seven days. Furthermore, it reduced H2O2 levels after two days (SS and SB) and lipid peroxidation in SB. Red LED increased phenols in both SS and SB but was detrimental to chlorophyll, carotenoids, and oxidative markers. Green LED had less significant effects. Microbiological growth varied with LED treatment: green light increased mesophilic bacteria in SB, and red light did so in SS by day four, while blue light reduced bacterial growth at the end of storage. Overall, Blue LED was the most effective LED in preserving postharvest quality. Soilless cultivation was particularly beneficial in reducing lipid peroxidation and maintaining cell membrane integrity during long-term storage, and it might also be more effective in preserving ascorbic acid. Conversely, soil-bound cultivation methods could enhance initial polyphenol content or better preserve it during early storage. This study highlights the complex interplay of pre-harvest conditions, postharvest quality, and shelf-life performance.

Phenylalanine, Cysteine, and Sodium Selenate Alleviate Chilling Injury in Cape Gooseberry (Physalis peruviana L.) Seedlings by Enhancing Antioxidant Activities and Membrane Stability

Low temperature is a major environmental factor that negatively affects the growth and productivity of plants, such as the tropical fruit Cape gooseberry (Physalis peruviana L.), which is susceptible to cold stress. Therefore, to investigate the effect of the amino acid L-phenylalanine (Phe), L-cysteine (Cys), or sodium selenite (Se) on enhancing antioxidant activities, experiments were conducted on the phenolic compounds, proline content, and membrane stability of Cape gooseberry seedlings under low-temperature stress. The seedlings were exposed for 48 h to a low temperature (4 °C) followed by 24 h of optimal growth conditions. In seedlings treated with Se, we found a high relative water content, good membrane integrity, low ion leakage, and hydrogen peroxide. Additionally, this treatment led to the improvement of photosynthetic pigments and antioxidant activity. The analysis of seedlings under cold stress showed that the Phe enhanced the stomatal conductance and phenol content. Furthermore, low concentrations of Cys resulted in the production of proline and flavonoids, which reduced the negative effects of environmental stress on seedlings and maintained cell membrane integrity. Overall, in this experiment, the use of Se and low concentrations of Cys had a positive effect on the amount of antioxidant compounds, which improved seedling growth under stress conditions.

Hydrogen sulfide attenuates chilling injury in loquat fruit by alleviating oxidative stress and maintaining cell membrane integrity

The effects of hydrogen sulfide (H2S) on chilling injury (CI), reactive oxygen species (ROS) metabolism, sugar metabolism, pentose phosphate pathway (PPP), and membrane lipid metabolism in loquat fruit throughout the refrigerated period were investigated in this study. The findings indicated that H2S application restrained the increase in internal browning (IB), malondialdehyde (MDA) content, and electrolyte leakage, while sustaining higher total phenolic and total flavonoid levels, and lower soluble quinone content in loquat fruit. Besides, H2S promoted antioxidant accumulation and increased antioxidant enzyme activities by the regulation of ROS metabolism, along with increasing fructose and glucose levels and reducing power by activating sugar metabolism and PPP. Furthermore, H2S treatment retarded the degradation of phospholipids and fatty acids in loquat fruit by modulating membrane lipid metabolism relevant enzyme activities. These findings indicated that H2S application mitigated CI in loquat fruit by alleviating oxidative stress and maintaining cell membrane structural integrity.

BSC2 modulates AmB resistance via the maintenance of intracellular sodium/potassium ion homeostasis in Saccharomyces cerevisiae

Previous studies on BSC2 have shown that it enhances yeast cell resistance to AmB via antioxidation and induces multidrug resistance by contributing to biofilm formation. Herein, we found that BSC2 overexpression could reverse the sensitivity of pmp3Δ to AmB and help the tested strains restore the intracellular sodium/potassium balance under exposure to AmB. Meanwhile, overexpression of the chitin gene CHS2 could simulate BSC2 to reverse the sensitivity of pmp3Δ and nha1Δ to high salt or AmB. However, BSC2 overexpression in flo11Δ failed to induce AmB resistance, form biofilms, and affect cell wall biogenesis, while CHS2 overexpression compensated the resistance of flo11Δ to AmB. Additionally, BSC2 levels were positively correlated with maintaining cell membrane integrity under exposure to AmB, CAS, or a combination of both. BSC2 overexpression in nha1Δ exhibited a similar function of CHS2, which can compensate for the sensitivity of the mutant to high salt. Altogether, the results demonstrate for the first time that BSC2 may promote ion equilibrium by strengthening cell walls and inhibiting membrane damage in a FLO path-dependent manner, thus enhancing the resistance of yeast cells to AmB. This study also reveals the possible mechanism of antifungal drugs CAS and AmB combined to inhibit fungi.

Requirement of Rab5 GTPase during heat stress-induced endocytosis in yeast

The plasma membrane (PM) is constantly exposed to various stresses from the extracellular environment, such as heat and oxidative stress. These stresses often cause denaturation of membrane proteins and destabilize PM integrity, which is essential for normal cell viability and function. For maintenance of PM integrity, most eukaryotic cells have the PM quality control (PMQC) system, which removes damaged membrane proteins by endocytosis. Removal of damaged proteins from the PM by ubiquitin-mediated endocytosis is a key mechanism for maintenance of the PM integrity, but the importance of the early endosome in the PMQC system is still not well understood. Here we show that key proteins in early/sorting endosome function, Vps21p (yeast Rab5), Vps15p (phosphatidylinositol-3 kinase subunit), and Vps3p/8p (CORVET complex subunits), are involved in maintaining PM integrity. We found that Vps21p-enriched endosomes change the localization in the vicinity of the PM in response to heat stress and then rapidly fuse and form the enlarged compartments to efficiently transport Can1p to the vacuole. Additionally, we show that the deubiquitinating enzyme Doa4p is also involved in the PM integrity and its deletion causes mislocalization of Vps21p to the vacuolar lumen. Interestingly, in cells lacking Doa4p or Vps21p the amounts of free ubiquitin are decreased, and overexpression of ubiquitin restored defective cargo internalization in vps9Δ cells, suggesting that defective PM integrity in vps9Δ cells is caused by lack of free ubiquitin.

Annexin-A5 monomer as a membrane repair agent for the treatment of renal ischemia-reperfusion injury.

Renal ischemia-reperfusion injury (IRI) is one of the causes of acute kidney injury. Annexin A5 (AnxA5), a calcium-dependent cell membrane-binding protein, shows protective effects in various organ IRI models. This study explored the therapeutic effect of exogenous AnxA5 monomer protein on renal IRI and its potential mechanism of action. Different doses of AnxA5 were injected intravenously to treat bilateral renal IRI in SD rats. This model confirmed the protective effects of AnxA5 on kidney structure and function. In vitro, HK-2 cells were subjected to hypoxia for 12h, followed by restoration of normal oxygen supply to simulate IRI. In vitro experiments demonstrated the mechanism of action of AnxA5 by measuring cellular activity and permeability. A comparison of the mutant AnxA5 protein M23 and the application of a calcium-free culture medium further validated the protective effect of AnxA5 by forming a network structure. Exogenous AnxA5 monomers prevented renal IRI by binding to the damaged renal tubular epithelial cell membrane, forming a two-dimensional network structure to maintain cell membrane integrity, and ultimately prevent cell death.

Milk Fat Globule Membranes for Mental Health across the Human Lifespan.

The milk fat globule membrane (MFGM) contains bioactive proteins, carbohydrates, and lipids. Polar lipids found in the MFGM play a critical role in maintaining cell membrane integrity and neuronal signalling capacity, thereby supporting brain health. This review summarises the literature on the MFGM and its phospholipid constituents for improvement of mental health across three key stages of the human lifespan, i.e., infancy, adulthood, and older age. MFGM supplementation may improve mental health by reducing neuroinflammation and supporting neurotransmitter synthesis through the gut-brain axis. Fortification of infant formula with MFGMs is designed to mimic the composition of breastmilk and optimise early gut and central nervous system development. Early behavioural and emotional development sets the stage for future mental health. In adults, promising results suggest that MFGMs can reduce the negative consequences of situational stress. Preclinical models of age-related cognitive decline suggest a role for the MFGM in supporting brain health in older age and reducing depressive symptoms. While there is preclinical and clinical evidence to support the use of MFGM supplementation for improved mental health, human studies with mental health as the primary target outcome are sparce. Further high-quality clinical trials examining the potential of the MFGM for psychological health improvement are important.

StMAPKK5 responds to heat stress by regulating potato growth, photosynthesis, and antioxidant defenses.

As a conserved signaling pathway, mitogen-activated protein kinase (MAPK) cascade regulates cellular signaling in response to abiotic stress. High temperature may contribute to a significant decrease in economic yield. However, research into the expression patterns of StMAPKK family genes under high temperature is limited and lacks experimental validation regarding their role in supporting potato plant growth. To trigger heat stress responses, potato plants were grown at 35°C. qRT-PCR was conducted to analyze the expression pattern of StMAPKK family genes in potato plants. Plant with StMAPKK5 loss-of-function and gain-of-function were developed. Potato growth and morphological features were assessed through measures of plant height, dry weight, and fresh weight. The antioxidant ability of StMAPKK5 was indicated by antioxidant enzyme activity and H2O2 content. Cell membrane integrity and permeability were suggested by relative electrical conductivity (REC), and contents of MDA and proline. Photosynthetic capacity was next determined. Further, mRNA expression of heat stress-responsive genes and antioxidant enzyme genes was examined. In reaction to heat stress, the expression profiles of StMAPKK family genes were changed. The StMAPKK5 protein is located to the nucleus, cytoplasm and cytomembrane, playing a role in controlling the height and weight of potato plants under heat stress conditions. StMAPKK5 over-expression promoted photosynthesis and maintained cell membrane integrity, while inhibited transpiration and stomatal conductance under heat stress. Overexpression of StMAPKK5 triggered biochemical defenses in potato plant against heat stress, modulating the levels of H2O2, MDA and proline, as well as the antioxidant activities of CAT, SOD and POD. Overexpression of StMAPKK5 elicited genetic responses in potato plants to heat stress, affecting heat stress-responsive genes and genes encoding antioxidant enzymes. StMAPKK5 can improve the resilience of potato plants to heat stress-induced damage, offering a promising approach for engineering potatoes with enhanced adaptability to challenging heat stress conditions.

Cassava Starch-Based Multifunctional Coating Incorporated with Zinc Oxide Nanoparticle to Enhance the Shelf Life of Passion Fruit

Passion fruits are susceptible to numerous postharvest challenges including weight loss, ethylene production, peel shrinkage, microbial growth, and pulp liquefaction. To mitigate these issues, yellow passion fruits were treated with hydroxypropyl cassava starch zinc oxide (HCS-ZnO) nanoparticles at varying concentrations. Fruits were stored at 10°C for 42 days, and the treated fruits underwent periodic assessments for weight loss, electrical conductivity, reducing sugar, total soluble solids (TSS), titratable acidity, and peel color. The results showed that a 0.8% HCS-ZnO nanoparticle coating could significantly reduce the weight loss of passion fruit during storage. However, compared to other treatments, a 0.2% HCS-ZnO nanoparticle coating demonstrated superior preservation of physicochemical properties, delayed discoloration, slowed ripening, maintained cell membrane integrity (electrical conductivity 1337 μs/cm), and reduced nutrient loss (titrable acidity 3.35 g/100 mL, TSS 17.9%, reducing sugar 5.1 g/100 g) at 42 days of storage. This innovative approach holds promise for commercial application, offering a sustainable solution to mitigate postharvest losses of passion fruit. The study underscores the potential of HCS-ZnO nanoparticles as effective coatings to uphold fruit quality and extend shelf life, presenting compelling insights for future fruit preservation strategies.

Combined application of sucrose and 1-MCP alleviated the senescence of Gynura bicolor DC through regulating hexose accumulation

As a leaf vegetable, Gynura bicolor DC (G. bicolor) experiences a rapid deterioration after harvest including insufficient supply of sugar and destruction of cell membranes. In this research, four treatments were experimented on G. bicolor including the control (CK), 12% (g/g) sucrose (ST), 10 μL L−1 1-MCP (MT), and the combination of sucrose and 1-MCP (SMT). The results showed that three treated groups reduced respiratory rate, inhibited hexose consumption and promoted the decrease of starch and sucrose, which was converted into hexose including glucose and fructose to maintain cell membrane integrity. Meanwhile, the activities of AI, NI, SS-C, amylase, and corresponding gene expression levels were significantly up-regulated in three treated groups at 1 d, among which AI played a crucial role in regulating the accumulation of hexose. Furthermore, ST exerted a pronounced effect on hexose accumulation at the beginning while MT reduced hexose consumption through lowered respiratory metabolism during storage. Notably, SMT exhibited an optimum preservation effect on inhibited respiratory metabolism, maintaining cell membrane integrity, enhancing the retention of hexose, indicating that a synergistic effect of ST and MT were developed during storage.

Lysophospholipid acyltransferase-mediated formation of saturated glycerophospholipids maintained cell membrane integrity for hypoxic adaptation.

Adaptation to hypoxia has attracted much public interest because of its clinical significance. However, hypoxic adaptation in the body is complicated and difficult to fully explore. To explore previously unknown conserved mechanisms and key proteins involved in hypoxic adaptation in different species, we first used a yeast model for mechanistic screening. Further multi-omics analyses in multiple species including yeast, zebrafish and mice revealed that glycerophospholipid metabolism was significantly involved in hypoxic adaptation with up-regulation of lysophospholipid acyltransferase (ALE1) in yeast, a key protein for the formation of dipalmitoyl phosphatidylcholine [DPPC (16:0/16:0)], which is a saturated phosphatidylcholine. Importantly, a mammalian homolog of ALE1, lysophosphatidylcholine acyltransferase 1 (LPCAT1), enhanced DPPC levels at the cell membrane and exhibited the same protective effect in mammalian cells under hypoxic conditions. DPPC supplementation effectively attenuated growth restriction, maintained cell membrane integrity and increased the expression of epidermal growth factor receptor under hypoxic conditions, but unsaturated phosphatidylcholine did not. In agreement with these findings, DPPC treatment could also repair hypoxic injury of intestinal mucosa in mice. Taken together, ALE1/LPCAT1-mediated DPPC formation, a key pathway of glycerophospholipid metabolism, is crucial for cell viability under hypoxic conditions. Moreover, we found that ALE1 was also involved in glycolysis to maintain sufficient survival conditions for yeast. The present study offers a novel approach to understanding lipid metabolism under hypoxia and provides new insights into treating hypoxia-related diseases.

Physiological Regulation of Photosynthetic-Related Indices, Antioxidant Defense, and Proline Anabolism on Drought Tolerance of Wild Soybean (Glycine soja L.)

Wild soybean (Glycine soja L.), drought-tolerant cultivar Tiefeng 31 (Glycine max L.), and drought-sensitive cultivar Fendou 93 (Glycine max L.) were used as materials to investigate the drought tolerance mechanism after 72 h 2.5 M PEG 8000 (osmotic potential −0.54 MPa)-simulated drought stress at the seedling stage. The results indicated that the leaves of the G. soja did not wilt under drought stress. However, both the drought-tolerant and drought-sensitive cultivated soybean cultivars experienced varying degrees of leaf wilt. Notably, the drought-sensitive cultivated soybean cultivars exhibited severe leaf wilt after the drought stress. Drought stress was determined to have a significant impact on the dry matter of the above-ground part of the drought-sensitive cultivar Fendou 93, followed by the drought-tolerant cultivar Tiefeng 31, with the lowest reduction observed in G. soja. Furthermore, the presence of drought stress resulted in the closure of leaf stomata. G. soja exhibited the highest proportion of stomatal opening per unit area, followed by the drought-tolerant cultivar Tiefeng 31, while the drought-sensitive cultivar Fendou 93 displayed the lowest percentage. Photosynthesis-related indexes, including photosynthetic rate, intercellular CO2, transpiration rate, and stomatal conductance, decreased in Fendou 93 and Tiefeng 31 after drought stress, but increased in G. soja. In terms of the antioxidant scavenging system, lower accumulation of malondialdehyde (MDA) was observed in G. soja and Tiefeng 31, along with higher activities of superoxide dismutase (SOD, EC 1.15.1.1) and catalase (CAT, EC 1.11.1.6) to counteract excess reactive oxygen species and maintain cell membrane integrity. In contrast, the drought-sensitive cultivar Fendou 93 had higher MDA content and higher activities of ascorbate peroxidase (APX, EC 1.11.1.11) and peroxidase (POD, 1.11.1.7). G. soja and Tiefeng 31 also exhibited less accumulation of osmolytes, including soluble sugar, soluble protein, and free proline content. The activities of δ-OAT, ProDH, and P5CS, key enzymes in proline anabolism, showed an initial increase under drought stress, followed by a decrease, and then an increase again at the end of drought stress in G. soja. Before drought stress, Tiefeng 31 had higher activities of ProDH and P5CS, which decreased with prolonged drought stress. Fendou 93 experienced an increase in the activities of δ-OAT, ProDH, and P5CS under drought stress. The δ-OAT gene expression levels were up-regulated in all three germplasms. The expression levels of the P5CS gene in Fendou 93 and Tiefeng 31 were down-regulated, while G. soja showed no significant change. The expression of the P5CR gene and ProDH gene was down-regulated in Fendou 93 and Tiefeng 31, but up-regulated in G. soja. This indicates that proline content is regulated at both the transcription and translation levels.

GP-fatty acid axis regulating the adaptive morphogenesis of VBNC bacteria in response to chlorine stress in the process of chlorination disinfection

Investigating the specific metabolic regulatory strategy of viable but non-culturable (VBNC) bacteria is crucial for understanding adaptive morphogenesis, processes of shrinking body size and maintaining cell membrane integrity. Metabolomic studies have revealed an upregulation in the metabolic competence of glycerophospholipids (GP) and fatty acid catabolism in VBNC bacteria. Disruption of the GP-fatty acid axis, as evidenced by scanning electron microscopy, hinders the maintenance of adaptive morphology. VBNC bacteria minimize cell size by consuming fatty acids to sustain intracellular energy metabolism. Concurrently, GP metabolism replenishes fatty acid consumption and upholds cell membrane integrity, preventing HClO intrusion. Regulation of the GP-fatty acid axis also sustains intracellular antioxidants (e.g. glutathione and ubiquinone), preventing lipid peroxidation. Moreover, disruption of the GP-fatty acid axis impedes biofilm formation (reduced by 94.77 %) and reactivation (reduced by 95.73 %) of VBNC bacteria, with negligible effects on culturable bacteria. The study underscores the GP-fatty acid axis regulation to form adaptive morphology is a fundamental survival strategy for VBNC bacteria. Developing an efficient disinfection method targeting the GP-fatty acid axis emerges as a promising strategy to mitigate the health risk of VBNC bacteria.

Enhanced shelf life quality of peaches (Prunus persica L.) using ethylene manipulating active packaging in e-commerce logistics

Ethylene manipulating active packaging can effectively maintain the quality of peaches during storage. To explore the effectiveness of ethylene manipulating active packaging during E-commerce logistics, 1-methylcyclopropene (1-MCP) paper cards and ethylene absorbent (EA) sachets were applied to the peaches. During the logistics process, the ambient temperature and the vibration intensity inside the packaging remain at a high level and fluctuates greatly. In comparison with the control group, 1-MCP and EA significantly reduced the respiration rate, delayed ethylene release, and maintained the firmness and volatile compounds in peaches under high temperature and vibration stress. Five days after storage, the peel firmness, flesh firmness, cohesiveness, and chewiness of 1-MCP treatment decreased by 0.15 N, 6.37 N, 0.10 and 0.78, respectively. The total lactone content of peaches in control group reached 3.79 % at 10th day of storage, which was 2.61 % and 2.44 % higher than 1-MCP and EA group respectively. Furthermore, 1-MCP and EA can inhibited the accumulation of MDA and maintained cell membrane integrity. Among them, 1-MCP was more effective than EA. In conclusion, peaches treated with 1-MCP paper cards during E-commerce logistics can maintain good quality and extend shelf life. Our results confirmed that ethylene manipulating active packaging could effectively prolong the shelf life of peaches during E-commerce logistics.

CHMP4B and VSP4A reverse GSDMD-mediated pyroptosis by cell membrane remodeling in endometrial carcinoma

BackgroundIn advanced and recurrent endometrial carcinoma (EC), the current state of immuno- or targeted therapy remains in the clinical research phase. Our study aimed to explore the role of the ESCRT machinery in maintaining cell membrane integrity and reversing pyroptotic cell death. MethodsImmunohistochemistry, western blotting, and co-immunoprecipitation were performed to determine the expression and relationship between GSDMD, CHMP4B, and VPS4A. We employed techniques such as FITC Annexin V/propidium iodide staining, Ca2+ fluorescence intensity, IL-1β enzyme-linked immunosorbent assay, and lactate dehydrogenase release assay to detect pyroptosis in endometrial cancer cells. Plasma membrane perforations and CHMP4B/VPS4A puncta were observed through electron and fluorescence confocal microscopy. ResultsWe showed that GSDMD, CHMP4B, and VPS4A were differentially expressed in the pyroptotic EC xenograft mouse model group, as well as high, moderate, and mild expression in EC cells treated with LPS and nigericin compared to endometrial epithelial cells. Co-IP confirmed the interaction between GSDMD, CHMP4B, and VPS4A. We found that GSDMD knockdown reduced PI-positive cells, Ca2+ efflux, IL-1β, and LDH release, while CHMP4B and VPS4A depletion enhanced these indicators in HEC1A and AN3CA cells. Electron microscopy showed membrane perforations correspondingly decreased with inactivated GSDMD and increased or decreased after CHMP4B and VPS4A depletion or overexpression in EC cells. Fluorescence confocal microscopy detected CHMP4B protein puncta associated with VPS4A at the injured plasma membrane in GSDMDNT cells. ConclusionsWe preliminary evidenced that CHMP4B and VPS4A reverses GSDMD-mediated pyroptosis by facilitating cell membrane remodeling in endometrial carcinoma. Targeting CHMP4B related proteins may promote pyroptosis in endometrial tumors.