Search Results (1,171)

The fast-growing cyanobacterium Synechococcus sp. PCC 11901 is emerging as a promising chassis for photosynthetic biomanufacturing. Here we report recombinant protein production in PCC 11901 via signal peptide-mediated secretion, enabling direct recovery of target proteins from the culture medium without cell disruption. Seven signal peptides spanning both Sec and Tat pathways are screened using eYFP as a reporter, with secretion quantified daily over seven days by fluorescence measurements. FutA, belonging to the Tat pathway from Synechocystis sp. PCC 6803, achieves 92.2% extracellular export by day 7, substantially outperforming all Sec candidates, including the best Sec signal peptide thermitase from Cyanobacterium aponinum PCC 10605 (55.7%). Signal peptide-bearing strains exhibit growth reductions of up to 26% relative to the wild-type, with FutA most affected, indicating a general metabolic cost correlated with secretion efficiency. The best-performing signal peptides from both pathways, FutA and thermitase, are validated with secretion of lichenase. Notably, the rank order of signal peptide performance is reversed for lichenase: thermitase demonstrates 2.6-fold higher extracellular activity than FutA, indicating that optimal signal peptide selection is cargo-dependent. These results establish PCC 11901 as a secretion-competent chassis and provide a rational framework for matching signal peptide pathways to target protein properties. Full article

In many parasitoid insects, especially hymenopteran parasitoids, venom is delivered around oviposition to override host physiology. Once viewed as a narrowly immunosuppressive secretion, parasitoid venom is now recognized as a multifunctional effector system targeting host immunity, development, metabolism, and behavior. This review synthesizes the venom apparatus, identification strategies, mechanisms of host manipulation, evolutionary processes, and biocontrol prospects, drawing primarily on Hymenoptera. A consistent pattern emerges: comparable host phenotypes arise from divergent molecular scaffolds, indicating functional rather than molecular convergence. Mechanistic evidence is strongest along six interlocking axes: inhibition of the prophenoloxidase cascade and melanization, disruption of cellular and humoral immunity, developmental arrest, metabolic reprogramming, and neuromuscular or behavioral manipulation. Outside Hymenoptera, the coleopteran ectoparasitoid Dastarcus helophoroides offers one of the clearest comparative cases: parasitization inhibits host melanization, alters phenoloxidase activity, and reduces antibacterial activity and circulating hemocyte abundance. As of today, fifty putative venom-like candidate proteins have been identified from larval whole-body proteomics, yet the secretory tissue remains anatomically unresolved, and no individual effector has been functionally validated. The central challenge is therefore the transition from candidate catalogs to mechanistically resolved repertoires, particularly outside Hymenoptera. Closing this gap will be important for evolutionary inference and the rational development of venom-based biocontrol tools. Full article

The senescence-associated secretory phenotype (SASP) contributes to various age-related pathologies. Methyl caffeate exhibits strong SASP-inhibitory activity; however, its molecular targets and the precise mechanisms underlying its effects remain unclear. Therefore, in this study, we performed affinity chromatography using methyl caffeate-immobilized beads to identify its intracellular binding proteins. The functional roles of the identified target were validated via knockdown experiments, assessment of SASP factor (interleukin [IL]-6 and IL-8) expression at the mRNA and secretion levels, and analysis of nuclear factor-κB and p38 mitogen-activated protein kinase signaling pathways. IQ motif-containing GTPase-activating protein 1 (IQGAP1) was identified as a methyl caffeate-binding partner. IQGAP1 knockdown significantly reduced IL-6 and IL-8 expression levels, mimicking the effects of methyl caffeate treatment. Furthermore, IQGAP1 depletion suppressed nuclear factor-κB activation and p38 phosphorylation. Overall, this study identified IQGAP1 as a critical scaffold protein essential for SASP induction and a target of methyl caffeate. Our findings provide key insights into SASP regulation, facilitating the development of SASP-modulating therapeutics targeting specific IQGAP1 domains. Full article

Porcine enteric coronaviruses (PECs), including porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), porcine deltacoronavirus (PDCoV), and swine acute diarrhea syndrome coronavirus (SADS-CoV), remain major causes of neonatal diarrhea, dehydration, mortality, and economic loss in swine production. Despite substantial progress in vaccine development, durable field protection is still inconsistent. In this narrative review, this narrative review synthesizes current knowledge on PEC vaccine design from three connected perspectives: antigenic breadth, mucosal immunity, and translational evaluation. The economic and virological context of PEC vaccine development is first summarized, including the recurrent production burden of PECs, coronavirus genome organization, structural proteins, and the central role of the spike protein in receptor engagement, membrane fusion, and neutralizing antibody induction. Key issues are then discussed, including how spike diversity, conformational stability, epitope accessibility, glycan shielding, and antigen matching influence protective breadth; why intestinal secretory IgA, mucosal immune-cell trafficking, local memory responses, and lactogenic immunity should be prioritized as biologically relevant endpoints; and how delivery route, adjuvant selection, and platform design shape response quality. Current evidence on recombinant protein, viral-vectored, nanoparticle, virus-like particle, probiotic, plant-derived, and mRNA-based approaches is compared with attention to both promise and current evidentiary and translational limitations. The available literature suggests that future progress in PEC vaccinology is likely to depend less on platform novelty alone than on integrated vaccine designs that align antigen selection, mucosal delivery, maternal–neonatal protection, heterologous challenge, manufacturability, and field applicability. Full article

Mycobacterium tuberculosis (Mtb) continues to pose a significant global health risk, primarily due to its capacity to modulate host immune responses and achieve prolonged persistence. Recent evidence has increasingly underscored the significance of epigenetic reprogramming as a principal mechanism through which Mtb modifies host cellular functions without altering the fundamental DNA sequence. This review gives a full picture of how Mtb secretory proteins work as nucleomodulins to directly target host chromatin and control gene expression. Mtb uses special secretion systems, such as the ESX (Type VII) and SecA2 pathways, to enable effector proteins to enter host cells. Some of these proteins move to the nucleus and interact with machinery that is linked to chromatin. These nucleomodulins facilitate various epigenetic modifications, encompassing non-canonical histone methylation, DNA methylation, and the modulation of histone acetylation, resulting in extensive transcriptional reprogramming of immune-related genes. These changes make important host defence mechanisms less effective, such as macrophage activation, antigen presentation, cytokine production, and antimicrobial responses. This helps bacteria survive and avoid the immune system. Epigenetic remodeling also affects the polarization and metabolic states of macrophages, which further affect the progression of disease. The reversible characteristics of epigenetic modifications offer a significant prospect for host-targeted therapeutic strategies. Targeting enzymes such as histone deacetylases and DNA methyltransferases has shown potential in restoring immune function and enhancing bacterial clearance, particularly when used in combination with conventional anti-tubercular therapies. Even with these improvements, there are still big problems with fully understanding the functional diversity of Mtb secretory proteins and turning these discoveries into useful medical tools. In general, understanding how Mtb-secreted nucleomodulins and host epigenetic regulation interact is important for understanding how tuberculosis works and finding new ways to treat it. Full article

Osteoporosis (OP) is a highly prevalent age-associated inflammatory bone disease that remains underdiagnosed and undertreated despite its substantial global burden. OP is characterized by impaired osteoblast (OB) function, alterations in the extracellular matrix and chronic, low-grade inflammation associated with aging (‘inflammaging’). Initial evidence suggests that the accumulation of senescent cells and their senescence-associated secretory phenotype (SASP) may contribute to disease progression. Additionally, growing evidence indicates a close relationship between osteogenesis and angiogenesis in OP. This study aimed to characterize senescence-associated secretory changes in primary human OBs from donors with OP and to assess their functional impact on endothelial cell behavior. Primary human OBs from donors with OP (n = 15; female: 9, male: 6) and without OP (n = 21; female: 14, male: 7) were analyzed for senescence-associated secretory profiles using ELISA, proteome arrays, and Western blot analysis. The effects of OB-conditioned media on endothelial cell behavior were assessed in endothelial cell migration assays. OBs from donors with OP showed a tendency toward increased senescence-associated features in the β-galactosidase assay, alongside an altered secretory phenotype characterized by increased IL-6, reduced IL-8 and angiogenin levels and decreased expression of extracellular matrix-associated proteins, such as osteopontin, osteonectin, progranulin and thrombospondin-1. Conditioned media from OBs from donors with OP significantly enhanced endothelial cell migration and proliferation in vitro. These findings suggest that OBs from donors with OP exhibit a SASP that may alter the angiogenic microenvironment in the bone. Full article

Background and Objectives: Conventional assays for M-protein detection in multiple myeloma (MM), including serum immunofixation electrophoresis (sIFE) and serum free light-chain (sFLC) assays, have limitations in selected clinical settings. This pilot study aimed to develop and preliminarily validate a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS)-based workflow using Kunitz trypsin inhibitor (KTI) as an internal standard for patient-specific serum M-protein light-chain tracking, particularly in low-level post-treatment samples in which conventional assays may be negative or difficult to interpret. Materials and Methods: A total of 55 serum samples from 25 patients with MM were analyzed. Serum immunoglobulin light-chain species were enriched using mixed κ/λ affinity beads, followed by reduction, KTI-based calibration, and MALDI-TOF MS analysis. Quantitative performance was evaluated using purified IgG1 κ standards. Time-matched sIFE and sFLC ratio results were used for descriptive comparison. Results: After KTI-based calibration, patient-specific M-protein light-chain molecular masses could be consistently identified. The assay showed good linearity over the range of 0.20–10.00 μg/mL, with a calibration equation of y = 6.0228x + 0.1063 and an R² of 0.9961. The limit of detection and limit of quantification were 0.002 μg/mL and 0.008 μg/mL, respectively. Intra-day and inter-day precision were acceptable, and recovery ranged from 96.0% to 101.2%. In selected low-level or discordant samples, including cases with therapeutic interference, polyclonal background, or non-secretory disease, MALDI-TOF MS provided exploratory complementary monitoring information. Conclusions: This KTI-calibrated MALDI-TOF MS workflow showed preliminary analytical performance within the validated low-concentration range and may serve as a complementary approach for patient-specific serum M-protein light-chain monitoring in selected clinical settings of MM. Larger independent studies are required before its clinical utility can be established. Full article

During the early growth stage, lambs are highly susceptible to pathogenic microbial invasion due to an underdeveloped intestinal structure, unstable microbial colonization, and immature mucosal immune function, leading to diarrhea, growth retardation, and elevated mortality factors that severely constrain the production efficiency and economic viability of the sheep industry. This study aimed to compare the regulatory effects of compound yeast culture (CYC) and yeast polysaccharides (YPs) on intestinal barrier function in Mongolian male lambs and clarify their underlying molecular mechanisms. Eighteen lambs were randomly assigned to three groups (n = 6/group): control group (basal diet), CYC group (40 g/kg), and YP group (3 g/kg). After a 30-day feeding trial, intestinal histomorphology, tight junction proteins, immune signaling pathways, and gut microbiota were analyzed. The results showed that both additives improved intestinal villus morphology, and CYC markedly increased the villus height/crypt depth ratio (p < 0.05). At the mechanical barrier level, CYC upregulated the protein expression of occludin, claudin-1, and ZO-1, whereas YPs increased occludin and ZO-1 expression (p < 0.05). Immunologically, CYC inhibited intestinal inflammation via the TLR4/TRAF6/MyD88/NF-κB pathway, increasing interleukin-10 (IL-10) and secretory immunoglobulin A (sIgA) while decreasing pro-inflammatory cytokines. YPs exerted similar anti-inflammatory effects through the TLR2/MyD88 pathway. Microbial analysis indicated that both additives increased the relative abundance of beneficial bacteria including Eubacterium, Bacillus, and Succinivibrio, while reducing the potential pathogen Mogibacterium. Spearman correlation analysis revealed that Mogibacterium was positively correlated with TNF-α and negatively correlated with occludin expression. In conclusion, CYC and YPs effectively enhance intestinal mechanical, immune, and biological barriers via different TLR-mediated pathways and microbial modulation. Both natural additives have great application potential for improving lamb health, reducing antibiotic dependence, and promoting sustainable green animal husbandry. Full article

Radiotherapy serves as a cornerstone of cancer treatment, but its efficacy is often compromised by radioresistance, a process in which cancer-associated fibroblasts (CAFs) play a critical role. Following irradiation, CAFs exhibit inherent radioresistance, not only surviving at higher doses but also undergoing profound functional reprogramming, including senescence, acquisition of a senescence-associated secretory phenotype (SASP), and myofibroblast activation. Importantly, CAFs employ multiple interconnected mechanisms to collectively drive radioresistance: sustained immunosuppression, pro-resistance paracrine signaling, exosome-mediated communication, and stromal remodeling. These reprogrammed CAFs create a microenvironment that paradoxically supports tumor recurrence and limits therapeutic efficacy. Intervention strategies targeting CAFs—including neutralizing soluble factors, blocking key signaling nodes, targeted therapies against fibroblast activation proteins, or disrupting exosome-mediated communication—have shown promise in preclinical studies. A deeper understanding of the complex interactions between radiotherapy and CAFs may ultimately drive a shift in therapeutic strategy from targeting tumor cells alone to leveraging the entire microenvironment to achieve durable antitumor effects. Full article

Hepatocellular carcinoma (HCC) represents one of the most lethal malignancies worldwide and is characterized by profound metabolic reprogramming during its development. Paraoxonase 1 (PON1), a liver-synthesized secretory protein involved in lipid metabolism, has an incompletely defined role in cancer biology. This study aimed to systematically investigate the expression pattern, clinical features, and biological function of PON1 in HCC through an integrated approach combining data mining, RNA-seq and experimental verification. Our results demonstrated that PON1 expression is significantly downregulated in HCC tissues compared with adjacent tissues. Clinically, significant disparities were observed in gender (χ² = 19.305, p < 0.0001), tumor stage (χ² = 18.030, p = 0.0004), and tumor grade (χ² = 13.391, p = 0.0039) between patients with high and low PON1 expression in HCC. Low PON1 expression was associated with poor prognosis (TCGA_LIHC, log-rank: χ² = 9.290, p = 0.0023; ICGC_LIRI, log-rank: χ² = 8.469, p = 0.0036; GSE14520, log-rank: χ² = 9.746, p = 0.0018). Univariate and multivariate Cox regression analyses revealed PON1 as an independent prognostic biomarker. Pathway analysis showed that PON1-positively correlated genes enriched in pathways such as peroxisome and fatty acid degradation, whereas PON1-negatively correlated genes mainly in the cell cycle pathway. Functional experiments confirmed that knockdown of PON1 promoted HCC cell proliferation, migration, invasion and inhibited apoptosis, whereas overexpression of PON1 reversed these malignant phenotypes. Mechanistically, we uncovered that PON1 exerts its tumor-suppressive effects by negatively regulating TANK and CXCL3, key molecules of the NOD-like receptor signaling pathway. In summary, our findings identify PON1 as an independent prognostic biomarker in HCC and demonstrate the tumor-suppressive role of PON1, indicating its potential as a therapeutic target for HCC. Full article

Ophiopogon japonicus (O. japonicus) by-products contain abundant nutrients and bioactive substances. In this study, we evaluated their effects on production performance and intestinal health in meat rabbits. Firstly, we measured the nutrient levels of O. japonicus by-products along with its digestibility in meat rabbits. Then, we replaced dietary alfalfa meal with O. japonicus by-products to evaluate its effects on growth performance, carcass traits, apparent digestibility, and intestinal immunity in meat rabbits. The results showed that the effects of O. japonicus by-products on growing meat rabbits varied over time. In the early phase (days 1–21), it significantly depressed average daily gain (ADG, p < 0.001) and average daily feed intake (ADFI, p < 0.001), and increased feed to gain ratio (F:G) (p < 0.001). However, in the later phase (days 22–35), a compensatory response emerged, with significantly increased ADG (p < 0.001) and reduced ADFI (p < 0.01) and F:G (p < 0.001). Despite this compensatory growth, the growth performance and feed efficiency for the entire experimental period were not improved. O. japonicus by-products decreased carcass weight significantly (p < 0.001), but did not significantly affect dressing percentage and meat traits (p > 0.05), while it significantly reduced the digestibility of crude protein (CP, p < 0.05), increased that of crude fiber (CF, p < 0.001), and reduced the activities of amylase (p < 0.01) and increased trypsin in cecal contents (p < 0.05). Additionally, O. japonicus by-products elevated the levels of secretory immunoglobulin A (sIgA) and interleukin-10 (IL-10) in ileal mucosa (p < 0.05). They did not significantly affect the cecal microbial community or short chain fatty acid (SCFA) levels (p > 0.05). Our research indicated that O. japonicus by-products possess a balanced nutritional composition and improve intestinal immunity in rabbit production, making them a viable feed ingredient to partially replace alfalfa meal. Full article

Background: Postmenopausal osteoporosis is associated with cellular senescence and the accumulation of the senescence-associated secretory phenotype (SASP). While mesenchymal stem cell (MSC)-derived exosomes show tissue repair potential, the efficacy and mechanisms of MSC-derived apoptotic vesicles (apoVs) remain unclear. This study compared MSC-apoVs and exosomes in postmenopausal osteoporosis and investigated the underlying epigenetic mechanisms. Methods: Therapeutic efficacy was evaluated in an ovariectomized (OVX) mouse model and senescent human bone marrow mesenchymal stem cells (hBMMSCs). Small RNA sequencing identified differential microRNA (miRNA) cargos between vesicle types. SASP-related cytokine expression (IL-6, TNF-α, MCP-1) and pathway activation were assessed by RT-qPCR, ELISA, and Western blot. Results: MSC-apoV treatment attenuated bone loss in OVX mice and reduced SASP expression in senescent hBMMSCs to a greater extent than exosomes. Small RNA sequencing revealed that apoVs were enriched with a specific miRNA cluster, including hsa-let-7b-5p, hsa-miR-92a-3p, and hsa-miR-98-5p. Bioinformatic analyses identified BRAF and CRKL as downstream targets of this miRNA cluster, supported by reduced protein levels after apoV treatment. Subsequent molecular assays showed that apoV treatment inhibited the phosphorylation of both the MAPK (p38 and JNK) and NF-κB (p65) signaling pathways, which correlated with reduced local inflammation in the bone marrow microenvironment and preserved osteogenic differentiation capacity. Conclusions: MSC-apoVs attenuate postmenopausal osteoporosis more effectively than exosomes. This enhanced efficacy is associated with the delivery of an enriched miRNA cluster that inhibits MAPK and NF-κB signaling, together with suppression of BRAF and CRKL protein expression. ApoVs may represent a cell-free therapeutic strategy for age-related bone loss. Full article

Cellular senescence drives aging and age-related disease through the accumulation of senescent cells and their senescence-associated secretory phenotype (SASP). Emerging evidence suggests intermittent (“hit-and-run”) senolytic interventions may improve healthspan by reducing senescent cell accumulation and the SASP. Healthy adults aged 45–79 were recruited for a decentralized, single-arm pilot study (NCT06953518) evaluating 2 days of nutraceutical supplementation (Qualia Senolytic). Fingerstick blood samples and validated quality of life (QoL) questionnaire data were collected on days 0 and 7. Primary outcomes were SASP biomarkers measured by the Olink^® Target 48 Cytokine panel, including tumor necrosis factor (TNF), interleukin-1 beta (IL-1β), interleukin-8 (CXCL8), and vascular endothelial growth factor A (VEGFA). Protein data were analyzed using linear mixed models and Wilcoxon signed-rank tests. Seventy-one adults enrolled and 53 (74.6%) provided paired protein samples. No significant changes occurred in primary outcomes. Exploratory unadjusted analyses revealed significant reductions in the established senescence chemokines CXCL9 and CXCL10, as well as CCL8 and CXCL11, and increases in interleukin-17F and oncostatin M. QoL significantly improved without safety concerns, though results are expectation-sensitive. Preliminary findings support the feasibility of this decentralized approach and identify candidate SASP biomarker signals in healthy adults warranting validation in randomized, placebo-controlled trials. Full article

Cervical cancer constitutes a major global health burden with a high incidence rate. Despite its well-established role in genome stability and cell cycle regulation, its specific anti-tumor mechanism involving the induction of a senescence-like state remains unclear. To determine whether Mg²⁺ impedes cervical cancer progression through the induction of a senescence-like phenotype via the ATM/CHK2/p21 pathway, HeLa cells were used in this study. Cell proliferation, migration, and invasion were measured using CCK-8, EdU, wound-healing, and Transwell assays, while SA-β-gal staining and western blotting served to examine both senescence-related markers and pathway protein expression. A BALB/c nude mouse xenograft model was established to evaluate tumor growth and safety following intratumoral Mg²⁺ injection. The results showed that Mg²⁺ inhibited proliferation, migration, and invasion in a concentration-dependent manner. Treatment with 20 mM Mg²⁺ increased SA-β-gal positivity, decreased Lamin B1 expression, and activated the ATM/CHK2/p21 pathway; moreover, this upregulation of p21 was reversed by an ATM inhibitor. ELISA revealed that 10 mM Mg²⁺ enhanced IL-6 and TNF-α secretion, confirming effective induction of the senescence-associated secretory phenotype, while higher concentrations diminished this effect, which may be partly attributed to the reduction in cell viability. In vivo experiments showed that Mg²⁺ inhibited tumor growth without notable alterations in body weight, liver and kidney function, or serum magnesium levels. In summary, the localized high concentration of magnesium ions induces cells to enter a senescence-like state via the ATM/CHK2/p21 pathway, thereby selectively suppressing malignant cellular behaviors. Notably, its in vivo efficacy and safety profile in vivo are favorable. It is also worth noting that these findings should be interpreted within the context of a preclinical, high-dose local Mg²⁺ model. Full article

Decidualization in the human endometrium is not merely a hormone-dependent differentiation process; rather, it represents a multilayered adaptive program characterized by the tight integration of immune regulation, metabolic reprogramming, and cellular stress responses. In this review, endoplasmic reticulum (ER) stress and the associated unfolded protein response (UPR) are proposed as central regulatory mechanisms governing this process. Triggered by increased protein synthesis and secretory demand, UPR activation under physiological conditions preserves proteostasis and supports the secretory capacity of stromal cells. In contrast, chronic or dysregulated activation leads to a maladaptive response characterized by apoptosis, inflammation, and metabolic dysfunction. UPR signaling pathways shape immune tolerance through their effects on macrophage polarization, uterine natural killer (uNK) cell function, and T cell balance. At the metabolic level, adenosine monophosphate-activated protein kinase (AMPK) regulates cellular adaptation through bidirectional interactions with mitochondrial function and redox homeostasis. Within this framework, the ER stress–immune–metabolic axis operates not as a linear pathway but as a dynamic network incorporating multiple feedback loops, thereby constituting a critical threshold mechanism that determines the success of decidualization. Disruption of this axis provides a shared mechanistic basis for pathologies such as recurrent implantation failure, pregnancy loss, and preeclampsia. From a therapeutic perspective, agents including chemical chaperones, UPR modulators, AMPK activators, and anti-inflammatory compounds hold translational potential by targeting these pathological feedback circuits. However, key knowledge gaps remain, particularly regarding the cell type-specific and temporal regulation of ER stress, the molecular boundaries defining the transition from adaptive to pathological states, and interspecies differences. Future studies employing single-cell omics approaches and functional in vivo models will be essential to elucidate the dynamic organization of this axis and to enable the development of targeted and personalized therapeutic strategies. Full article