Search Results (3,008)

Background/Objectives: Anabolic resistance is thought to underlie muscle loss in sarcopenia. Here, we investigated the adjuvant role of beta-hydroxy-beta-methylbutyrate (HMB), a leucine metabolite, on the acute muscle anabolic response to oral protein supplementation in older adults. Methods: A total of 24 community-dwelling older adults (68.5 ± 0.6 years; 13 men, 11 women) were randomized in a cross-over double-blind design to 40 g whey protein (Control) or 40 g whey protein with 3 g calcium–HMB (HMB). Subjects received a primed constant infusion of ¹³C₆ phenylalanine to assess muscle protein synthesis (MPS, by tracer incorporation in myofibrils) and muscle protein breakdown (MPB, via arterio-venous dilution) at baseline and post supplementation. Fasted and 3 h fed-state plasma HMB, aminoacidemia, rates of MPS, MPB, limb and muscle blood flow were measured. Results: In all subjects, both interventions displayed significant increases in MPS in response to feeding [fasted to 3 h-fed change (mean ± SEM, standard error of the mean). Males: control, +0.032 ± 0.006%.h⁻¹; HMB, +0.023 ± 0.004%.h⁻¹; females: control, +0.023 ± 0.006%.h⁻¹; HMB, +0.038 ± 0.006%.h⁻¹, p < 0.05]. In older women, the addition of HMB further enhanced the MPS response (fasted to 3 h-fed change, p = 0.0495) and area under the curve (p = 0.0364) versus protein alone. During the late-fed period, MPB significantly decreased in HMB versus control (p = 0.0298), and this was also observed when subjects were separated by sex (p = 0.0012). Conclusions: High-dose protein bolus feeding increased MPS in older adults. Surprisingly, 40 g whey did not maximize the anabolic response in older women, and HMB further increased the MPS feeding response to protein. HMB further suppressed the MPB feeding response over a longer period of time. Further work is needed to understand the apparent sexual dimorphic MPS response to high protein. Full article

Cadmium (Cd) is a pervasive environmental contaminant with potent cytotoxic effects in a wide range of organisms. Although autophagy and apoptosis are recognized as major cellular responses to heavy metal stress, the molecular basis of Cd-induced cell death in insects remains insufficiently understood. In this study, we used fifth-instar day-4 (5L4D) larvae of Bombyx mori and the silkworm-derived Bm-12 cell line to investigate the involvement of three core autophagy-related proteins, Bombyx mori Autophagy-related protein 5(BmATG5), Bombyx mori Autophagy-related protein 6(BmATG6), and Autophagy-related protein 8(BmATG8), in Cd-induced autophagy and apoptosis. Exposure to CdCl₂ markedly induced autophagic and apoptotic responses in both larval midgut tissue and Bm-12 cells, as demonstrated by monodansylcadaverine(MDC) staining, Lyso-Tracker Red staining, DAPI and Hoechst 33258 staining, and DNA fragmentation assays. qPCR and Western blot analyses showed significant upregulation of BmATG5, BmATG6, and BmATG8 following Cd exposure. Notably, the cleaved forms tBmATG5-N (24 kDa) and tBmATG6-C (35 and 37 kDa), as well as the lipidated form BmATG8-PE (12 kDa), accumulated substantially under Cd stress. In parallel, intracellular Ca²⁺ levels and calpain activity were significantly increased, suggesting activation of a calcium-dependent regulatory pathway. Pharmacological inhibition experiments further indicated that autophagy and apoptosis are functionally interconnected during the Cd response. Collectively, these findings demonstrate that BmATG5, BmATG6, and BmATG8, together with their processed forms, play central roles in coordinating autophagy–apoptosis crosstalk during Cd-induced cytotoxicity in Bombyx mori. This study provides new mechanistic insight into heavy metal toxicity in insects and expands our understanding of stress-induced programmed cell death during silkworm metamorphosis. Full article

Cadmium (Cd) is a typical heavy metal pollutant in aquatic environments. It enters fish through the gills, digestive tract, and body surface, and accumulates mainly in the liver and kidneys, with species- and tissue-specific distribution. Cadmium triggers apoptosis by inducing oxidative stress, calcium imbalance, and DNA damage. These signals are integrated and amplified by the mitogen-activated protein kinase (MAPK), nuclear factor kappa B (NF-κB), phosphatidylinositol 3-kinase (PI3K)/AKT, and nuclear factor erythroid 2-related factor 2 (Nrf2) pathways, ultimately activating three downstream apoptotic execution pathways: the death receptor, mitochondrial, and endoplasmic reticulum stress pathways. These three pathways form an interactive network through molecular nodes such as BH3 interacting domain death agonist (Bid), Ca²⁺, c-Jun N-terminal kinase (JNK), and C/EBP homologous protein (CHOP), synergistically amplifying the apoptotic effect, with the mitochondrial pathway playing a central role. Cadmium-induced apoptosis is dose-dependent: low concentrations activate protective responses, whereas high concentrations strongly promote apoptosis. Current research gaps remain regarding dynamic pathway crosstalk, chronic low-dose effects, species differences, and fish-specific apoptotic molecules (e.g., caspase-12 homologs). Future studies should focus on constructing multidimensional response maps, clarifying pathway activation thresholds and interaction contributions, and developing composite protective strategies based on Nrf2 activators, metal chelators, and antioxidants, thereby promoting translation into ecological risk assessment and aquaculture pollution control. Full article

Latrophilin 1 (LPHN1/ADGRL1), an adhesion G-protein-coupled receptor (GPCR), is the principal receptor for α-latrotoxin (αLTX), a toxin that triggers massive neurotransmitter release. However, its endogenous signaling mechanism remains elusive. Here, we dissect the LPHN1 signaling pathway at the vertebrate neuromuscular junction, using the pore-deficient αLTX mutant LTX^N4C as a selective agonist. Combining electrophysiological recordings from LPHN1 knockout mice with pharmacological inhibitors, calcium imaging, and biochemical assays, we delineate the cascade from receptor activation to spontaneous quantal acetylcholine release. We demonstrate that LPHN1 is specifically localized to the presynaptic membrane and mediates LTX^N4C-evoked release. Upon activation, LPHN1 engages the G_αq–phospholipase C pathway to generate inositol 1,4,5-trisphosphate (IP₃), triggering Ca²⁺ release from intracellular stores via IP₃ receptors. This store depletion activates store-operated Ca²⁺ entry (SOCE), providing sustained Ca²⁺ required for LTX^N4C-induced burst-like exocytosis. We uncover distinct roles for Ca_V2.1 and Ca_V1 channels in initiating and sustaining this response. These findings establish LPHN1 as a GPCR that harnesses intracellular stores and SOCE to drive spontaneous neurotransmission, revealing a novel signaling paradigm for adhesion GPCRs in presynaptic function. Full article

Arachidonic acid (AA) is an emerging regulator of fibroblast activity in pulmonary fibrosis; however, the underlying intracellular mechanisms remain unclear. This study investigated the effects of AA on the free intracellular calcium concentration ([Ca²⁺]_i), nitric oxide (NO), and reactive oxygen species (ROS) in human WI-38 lung fibroblasts. Using fluorescent imaging and pharmacological tools, we demonstrate that AA evokes a robust, concentration-dependent increase in [Ca²⁺]_i. This response is initiated by G protein-coupled receptor 40 (GPR40), which leads to endoplasmic reticulum Ca²⁺ release through inositol 1,4,5-trisphosphate receptors (IP₃Rs) and lysosomal Ca²⁺ mobilisation through two-pore channels (TPCs). Sustained Ca²⁺ elevation is primarily mediated by influx through transient receptor potential vanilloid 4 (TRPV4) channels, with a minor contribution from store-operated Ca²⁺ entry. The AA-induced Ca²⁺ signal stimulates endothelial NO synthase-dependent NO production, which in turn triggers ROS generation, revealing a tightly coupled Ca²⁺–NO–ROS signalling network. Our findings identify AA as a potent modulator of Ca²⁺ and redox signalling in lung fibroblasts, and highlight GPR40, TRPV4, IP₃Rs and lysosomal TPCs as potential therapeutic targets for intervening in pulmonary fibrosis. Full article

Gla-rich protein (GRP), also known as UCMA, is a vitamin K-dependent protein that has emerged as an important regulator of pathological calcification and inflammation. Vascular calcification is a major complication of chronic kidney disease and cardiovascular disorders and is now recognized as an active and tightly regulated process rather than a passive accumulation of minerals. Increasing evidence indicates that GRP plays a protective role in mineral homeostasis through its strong calcium-binding capacity and its dependence on vitamin K-mediated gamma carboxylation. This work represents a comprehensive narrative review aimed at summarizing and critically discussing the current scientific knowledge on GRP. Available experimental and clinical data are analyzed with respect to gene expression, molecular regulation, vitamin K dependency, and underlying mechanisms of action. Particular emphasis is placed on the dual function of GRP in inhibiting ectopic calcification and modulating inflammatory responses. The evidence linking altered GRP levels or changes in its carboxylation status with chronic kidney disease, vascular calcification, calcific aortic valve disease, osteoarthritis, and tumor-associated microcalcifications is systematically examined. Current findings collectively support the concept that GRP is a multifunctional protein operating at the interface of mineral metabolism, inflammation, and tissue remodeling. Despite promising experimental data, important knowledge gaps remain, including the absence of standardized assays capable of distinguishing different GRP forms and the lack of longitudinal clinical studies evaluating its predictive value. This manuscript highlights the potential of GRP as a biomarker of disturbed mineral homeostasis and cardiovascular risk, while emphasizing the need for further research to clarify its precise biological functions and clinical relevance. Full article

Soil salinity limits ginger productivity, but the underlying molecular mechanisms remain largely unclear. The 14-3-3 proteins are conserved regulators in stress signaling. Here, we genome-wide characterized the 14-3-3 family in Zingiber officinale and examined the possible involvement of Zo14-3-3-03 in salt response. A total of 21 Zo14-3-3 genes were identified and classified into four groups with uneven chromosomal distribution. Among them, Zo14-3-3-03 was strongly salt-responsive: transcript levels increased 9.91- to 33.82-fold during 1–7 days of treatment and reached 62.47-fold in leaves at day 14. NaCl treatment elevated GUS expression driven by the Zo14-3-3-03 promoter. Virus-induced gene silencing (VIGS) of Zo14-3-3-03 resulted in silenced plants exhibiting higher malondialdehyde (up to 73.6%), lower antioxidant enzyme activities (SOD, POD, CAT, and APX: 18.9–31.9% reduction), reduced osmolytes (proline, soluble protein, sugars, and ascorbic acid: 23.2–36.2% reduction), excessive reactive oxygen species, and decreased relative water content. Several antioxidant-related genes were significantly downregulated. Protein interaction assays suggested a possible interaction with ZoSOS2, and the expression of SOS2 pathway genes was altered in silenced plants, indicating a potential link to calcium signaling and ion homeostasis. Taken together, these results suggest that Zo14-3-3-03 participates in ginger salt stress response possibly through redox balance, osmotic adjustment, and calcium-mediated pathways which would provide a basis for understanding 14-3-3-mediated stress responses and nominates Zo14-3-3-03 as a candidate requiring deeper validation for salt tolerance improvement in ginger. Nevertheless, due to limited functional validation, its role as a positive regulator and breeding target remains preliminary. Further genetic and mechanistic studies are needed to confirm causality and assess field-level applicability. Full article

Plant-derived coagulants are increasingly explored as alternatives to animal rennet. This study provides the first evaluation of the coagulation kinetics and technological properties of Onopordum platylepis Murb. in ewe’s milk. Response surface methodology was applied to optimize temperature (30, 33, and 36 °C), pH (5.5, 6.0, and 6.5), and calcium chloride concentration (2, 4, and 6 mM). The optimal conditions for minimizing milk-clotting time were 36 °C, pH 5.5, and 6 mM CaCl₂. Under standardized activity (50 IMCU/L), the Rheological properties of gels produced by Onopordum platylepis were compared with Cynara cardunculus, Cynara humilis, animal rennet, a commercial plant coagulant, and fermentation-produced chymosin. Onopordum platylepis showed slower curd-firming rates than animal rennet and Cynara cardunculus, but similar behavior to Cynara humilis. Gels produced with Onopordum platylepis exhibited firmness comparable to commercial plant coagulants. The water-holding capacity was similar to other coagulants, though protein losses were higher for Onopordum platylepis, Cynara humilis, and Cynara cardunculus than animal rennet. Overall, Onopordum platylepis demonstrates potential for ewe’s milk cheese production, in which highly proteolytic coagulants are used. Full article

Ischemic stroke remains a leading cause of death and disability worldwide. While thrombolysis and endovascular thrombectomy are current mainstays of treatment, their clinical efficacy is often undermined by ischemia–reperfusion injury (I/R). This injury induces secondary brain damage, primarily via disruption of the blood–brain barrier (BBB). No approved therapies directly target BBB protection. This review reinterprets the pathophysiological mechanism of BBB disruption after stroke through a dynamic spatiotemporal framework. The pathological cascade reaction is clearly divided into two core stages: the ischemic phase is mainly driven by energy failure and calcium overload; the reperfusion phase is further divided into four consecutive and progressive sub-stages, namely, oxidative stress burst, amplification of inflammatory response, matrix metalloproteinase 9 (MMP-9)-mediated barrier degradation and programmed cell death. This review critically assesses current therapies and identifies major clinical translation gaps, including a temporal mismatch between preclinical and clinical windows, unacceptable toxicity, lack of durable efficacy and biphasic effects. Matching specific interventions to the different pathophysiological stages of blood–brain barrier disruption is essential for optimizing clinical outcomes. Full article

Wetland ecosystems have been a central focus of ecological research for an quite some time. Nevertheless, the degradation of wetland riparian zones has markedly accelerated due to anthropogenic activities, climate change, and habitat heterogeneity. The objective of this paper is to investigate the differences in functional traits of riparian plants under changing wetland environments on a karst plateau, as well as to elucidate the adaptive strategies of wetland plants across different habitats. This study examines the Caohai Wetland located on the Guizhou karst plateau, selecting the leaves of four dominant plant species (Phragmites australis, Onopordum acanthium, Galium odoratum, Paspalum distichum) in the Caohai Wetland lakeshore zone and analyzes the influence of soil factors on the variation of plant functional traits within the wetland riparian zone. The results reveal that: (1) significant differences exist in the functional traits of dominant plants in the riparian zones of karst plateau wetlands, with complex interrelationships among these traits; (2) the coefficients of variation for magnesium (Mg) and calcium (Ca) in the soil are notably high (79.53% and 67.21%, respectively), whereas soil oxidation-reduction potential (ORP) exhibits the lowest coefficient of variation (4.36%)—furthermore, the convergent variation in specific leaf area (SLA) and leaf dry matter content (LDMC) directly reflects the strong environmental filtering imposed by this habitat—and (3) redundancy analysis (RDA) indicates that leaf length (LL), specific leaf area (SLA), leaf area (LA), and plant carbon content (PCC) are particularly sensitive to environmental changes, while soil calcium (Ca), total nitrogen (TN), water-dispersible clay (WDR), soil organic matter (SOM), soil moisture content (SPMC), and total potassium (TK) constitute the principal soil factors influencing plant adaptive strategies in karst plateau wetlands. In conclusion, this study demonstrates that adaptation to karst wetland habitats is mediated through trade-offs in the allocation of photosynthetic products and the regulation of carbon (C), nitrogen (N), and phosphorus (P) nutrient balances under calcium-enriched and phosphorus-limited conditions, thereby reflecting the response characteristics of functional traits in karst plateau wetland plants to environmental changes. Full article

Since MDCK cells are inherently tumorigenic, their safety in vaccine production has long been a concern; thus, establishing a screening method for low-tumorigenic cells is of great significance for influenza vaccine development. This study successfully obtained a low-tumorigenic MDCK cell line through monoclonal screening and systematically evaluated its potential as a cellular substrate for influenza vaccines using male nude mice (BALB/c nu/nu, 4–7 weeks old) for tumorigenicity assessment. Comprehensive analysis of the biological characteristics of the screened cells—including growth curves and transcriptomic features—showed that the cell line exhibits stable growth and consistent traits. Transcriptomic comparison was performed between two defined biological states: parental MDCK cells (SQ group) and the low-tumorigenic clone MDCK-20B9 (SH group). Transcriptomic analysis revealed good dispersion among samples and an overall consistent gene expression distribution. Differential expression analysis identified a total of 2198 differentially expressed genes, including 902 upregulated and 1296 downregulated genes. GO functional enrichment analysis indicated that these genes are mainly involved in biological processes such as acute-phase response, retinol metabolism, mitotic chromosome condensation, and cell migration; are enriched in cellular components such as kinetochores and the extracellular matrix; and are associated with molecular functions including calcium ion binding and the Wnt signaling pathway. KEGG pathway analysis further revealed that the differentially expressed genes are significantly enriched in key pathways such as cancer pathways, cell cycle, and cell adhesion molecules. The expression trends of five key differentially expressed genes were validated by RT-qPCR. In summary, this study successfully screened a stable and consistent low-tumorigenic MDCK cell line, providing a theoretical basis and practical foundation for its use as a cellular substrate in influenza vaccine development. Full article

The plasma membrane plays essential roles in cellular transport and signaling. One of its fundamental structural features is the asymmetric distribution of lipids between the inner and outer leaflets. This asymmetry is actively maintained by lipid transport systems, including flippases, floppases, and scramblases, and is critical for membrane integrity and signaling regulation. Accumulating evidence indicates that membrane lipid asymmetry is frequently altered in cancer cells, leading to the externalization of normally inner-leaflet phospholipids such as phosphatidylserine and phosphatidylethanolamine. These alterations can influence tumor signaling, immune interactions, and membrane-associated biological processes. Recent studies further suggest that metabolic reprogramming in cancer may play an important role in regulating membrane lipid asymmetry. Changes in cellular energy status, oxidative stress, calcium signaling, and lipid metabolism can modulate lipid transport systems and membrane organization. In addition, tumor metabolism generates diverse circulating metabolites, including lactate, lysophospholipids, and acylcarnitines, which may influence membrane properties and lipid redistribution. These observations raise the possibility that membrane lipid asymmetry functions as a metabolically responsive interface linking intracellular metabolic state to cell surface signaling and tumor–microenvironment interactions. In this review, we propose a conceptual framework in which cancer-associated metabolic reprogramming influences lipid transport systems and membrane organization, thereby reshaping phospholipid distribution across the plasma membrane. We discuss how metabolic perturbations—including changes in energy metabolism, redox balance, calcium signaling, and lipid remodeling—may regulate membrane lipid asymmetry and explore the implications of these processes for tumor signaling, immune interactions, and emerging membrane-targeted therapeutic strategies. Full article

This work investigated the potential of different natural fillers, i.e., clay, calcium carbonate, and silica, as sustainable alternatives to glass fibers (GFs) in polyamide 6 (PA6) for Large-Format Additive Manufacturing (LFAM) applications in order to guarantee the chemical recyclability of the produced materials. Specifically, PA6-based composites containing ≤ 10 wt% natural fillers were compared with a conventional system (30 wt% GF-reinforced PA6) from rheological, morphological and thermo-mechanical perspectives. Rheological analysis showed that silica- and clay-filled samples displayed similar rheological response to the GF-filled reference due to their large particle size. Thermal analyses revealed a slight increase in crystallinity (up to 32%) for filled samples, indicating a potential nucleating effect of the natural fillers. Calcium carbonate-filled composites achieved thermal conductivity values comparable to the GF-filled reference (≥0.42 W/mK) indicating a high heat dissipation capability during printing operations. Morphological analysis performed on preliminary LFAM components revealed satisfactory printing quality and good filler dispersion. Flexural tests showed that silica and calcium carbonate could provide a balanced mechanical response, thereby reducing the anisotropy of printed components. These results demonstrated that the addition of suitable natural fillers at limited concentrations (≤10 wt%) can represent a lightweight and eco-sustainable alternative to GF reinforcement in LFAM applications. Full article

The severe continuous cropping obstacles in Morchella cultivation, driven primarily by soil microecological imbalance, critically constrain the sustainable development of the industry. To address this challenge, this study evaluated the efficacy of rotary tillage, calcium cyanamide (CaCN₂), and organic fertilizer, applied individually and in combination, in mitigating these obstacles and explored the underlying microbial mechanisms. The soil was treated on 5 August 2024, and soil samples were collected on 5 October 2024. Four treatments were established: continuous cropping control (CK), rotary tillage (XGX), rotary tillage combined with calcium cyanamide (MPD), and rotary tillage combined with calcium cyanamide and organic fertilizer (MPX). Soil chemical properties were analyzed in conjunction with metagenomic sequencing to characterize the responses of soil properties and microbial communities, including both eukaryotic and bacterial taxa. The results indicated that the MPD treatment showed a relatively pronounced effect in enhancing key soil fertility indicators, including soil organic matter (OM), total nitrogen (TN), available nitrogen (AN), available potassium (AK), and total phosphorus (TP). All amendments significantly altered microbial community structures. Specifically, the integrated MPX treatment effectively reduced the relative abundance of the pathogenic fungus Olpidium while maintaining higher overall microbial diversity. It also significantly promoted the abundance of Morchella itself and beneficial bacterial phyla such as Actinomycetota and Pseudomonadota. Redundancy analysis identified AN and AK as the primary drivers of eukaryotic community variation, whereas Availa-ble phosphorus (AP) and potential of hydrogen (pH) were the key factors shaping the bacterial community. The results indicated that MPD was the showed relatively pronounced effectiveness in rapidly improving soil fertility and suppressing pathogenic fungi. In contrast, MPX showed relatively better performance in optimizing microbial community structure, enhancing microbial diversity, and strengthening overall ecological stability. These two treatments exhibited distinct advantages in soil chemical improvement and microbial community regulation, respectively, thereby providing alternative practical strategies and a theoretical basis for the ecological management of continuous-cropping obstacles in Morchella cultivation. It should be noted that this study did not include treatments with calcium cyanamide alone, organic fertilizer alone, or their combined application without rotary tillage. This is primarily because rotary tillage is a standard land preparation practice in Morchella cultivation, and the use of soil amendments without accompanying tillage is rarely adopted under practical production conditions. Full article

Background: In the Republic of Korea, a bivalent foot-and-mouth disease (FMD) vaccine covering serotypes O and A is administered to livestock, while antigens for the other serotypes are stockpiled in overseas antigen banks. To achieve self-reliance in FMD vaccine production, various vaccine strains have been developed using in-house technology. Although SAT 3 has historically been confined largely to Africa, preparedness against this serotype remains necessary, as the possibility of its introduction into Korea cannot be completely excluded. Methods: In this regard, we evaluated the commercial potential of the SAT 3 ZIM-R vaccine strain by assessing antigen productivity, scalability, inactivation kinetics, and immunogenicity. Results: Supplementation with 3 mM Ca²⁺ markedly increased antigen yield compared with that obtained in the absence of calcium. Further optimization showed that antigen yield was highest at pH 8.0–8.5. During scale-up, antigen yield was maintained at 9.2–9.8 μg/mL in flask cultures and remained high at approximately 7.8 μg/mL in a bioreactor, demonstrating robust scalability. Treatment with 2 mM binary ethylenimine at 26 °C achieved complete inactivation within 24 h. Vaccines formulated with the SAT 3 ZIM-R antigen produced either in flasks or in a bioreactor induced comparable neutralizing antibody responses in pigs following both the primary and booster immunizations. Conclusions: Collectively, these findings indicate that SAT 3 ZIM-R is a promising vaccine candidate for large-scale vaccine antigen production and the future establishment of a domestic FMD antigen bank in Korea. Full article