The genus Brucella comprises important human and animal pathogens, as well as numerous environmental and symbiotic species. Lipopolysaccharide (LPS), a major component of the outer membrane of Gram-negative bacteria, plays a crucial role in bacterial physiology and host interactions. In this study, the structures of lipid A, the hydrophobic anchor of lipopolysaccharide, isolated from two plant-associated strains, Brucella cytisi ESC1ᵀ and Brucella lupini LUP21ᵀ, were presented. Lipid A preparations were structurally characterized using chemical methods, MALDI-TOF mass spectrometry, and nuclear magnetic resonance spectroscopy. The obtained results indicated that both lipid A molecules have almost identical structures. Their sugar backbones consist exclusively of 2,3-diamino-2,3-dideoxy-d-glucose (d-GlcpN3N). Phosphate residues were connected to distal and proximal GlcpN3N in approximately half of the lipid A molecules. Fatty acid analysis revealed the presence of C14:0 (3-OH), C16:0 (3-OH), and traces of C18:0 (3-OH). All of these were primary fatty substituents of the sugar backbone and were amide-linked residues. Lactobacillic acid C19:0cyc and 27-hydroxyoctacosanoic acid (C28:0 (27-OH)) were found as ester-linked secondary acyl residues. In turn, C28:0 (27-OH) was partly esterified by a 3-hydroxybutyroyl residue. Two unsubstituted 3-hydroxyfatty acids were linked exclusively to the proximal d-GlcpN3N residue. It was pointed out that sequences of putative genes encoding enzymes required for lipid A biosynthesis and genes encoding specific enzymes involved in structural modifications of lipid A occurring in the genomes of both bacterial species are almost identical. The high sequence similarity of these proteins reflects the observed similarities in the lipid A structures in both investigated Brucella species.
α-Synuclein is an intrinsically disordered protein whose ensemble is shaped by both local structural preferences and global chain dimensions. Here, we combined BioMatics/AlphaFold2/AFflecto-derived structures with molecular dynamics simulations to generate a pool of α-synuclein conformations. Predicted chemical shifts were reweighted against experimental NMR chemical shifts using Bayesian Maximum Entropy reweighting. Global analyses showed that MD conformations remained compact and internally contact rich, while BioMatics/AlphaFold2/AFflecto conformations occupied a more expanded Rg and Ree regime. These results reveal a local-global discrepancy in α-synuclein ensemble refinement. Namely, chemical shift-guided BME preferentially supports MD-derived local conformations, whereas global descriptors favor a more expanded BioMatics/AlphaFold2/AFflecto-like ensemble. Our findings highlight the need to combine local NMR restraints with global observables such as SAXS, smFRET, and PRE for accurate modeling of intrinsically disordered protein ensembles. A major future improvement would be to develop multi-restraint BME reweighting, where chemical shifts are combined with SAXS-derived Rg, smFRET distances, PRE-derived long-range contacts, RDCs, hydrodynamic radius, and NMR relaxation data.
Triple-negative breast cancer (TNBC) is an aggressive subtype with limited therapeutic options. While metabolic reprogramming is a hallmark of cancer, most studies have focused on cell-intrinsic alterations in glucose and amino acid metabolism, with comparatively little attention paid to how cancer cells sense and respond to extracellular lipid availability. Here, through an unbiased transcriptomic and circRNA profiling screen under lipoprotein-deprived conditions, we identify circCTCF, a circular RNA derived from the CTCF gene, as a lipoprotein-responsive regulator of lipid metabolism and proliferation in TNBC. circCTCF is significantly downregulated upon lipid withdrawal, and its depletion impairs cell growth while promoting lipid droplet accumulation. Conversely, circCTCF overexpression enhances proliferation and suppresses lipid storage. Mechanistically, circCTCF binds the RNA-binding protein G3BP2 through its back-splice junction sequence to stabilize ACSL5 mRNA, thereby sustaining ACSL5 expression, phosphatidic acid (PA) levels, and mTOR signaling. ACSL5 overexpression rescues PA and mTOR activity in circCTCF-deficient cells, establishing a linear circCTCF-ACSL5-PA-mTOR axis. Furthermore, circCTCF associates with G3BP2-positive stress granules upon heat shock, suggesting a potential link between this metabolic axis and stress-induced RNA regulatory networks. Collectively, these findings establish circCTCF as a critical node coupling extracellular lipid cues to intracellular metabolic control and identify the circCTCF-ACSL5-PA-mTOR axis as a potential therapeutic vulnerability in TNBC.
Bio-based superabsorbent polymers (SAPs) were successfully prepared through a sustainable solvent-free and catalyst-free mechanochemical esterification of paramylon and zein using succinic anhydride as the esterification reagent. By optimizing the reaction temperature and raw material composition, a paramylon-to-zein weight ratio of 4:6 exhibited a porous morphology and achieved a maximum water absorption capacity of approximately 60 g/g, comparable to that of a commercial bio-based SAP. The optimized SAP also exhibited favorable biodegradability and showed no observable phytotoxicity in seed germination tests. Furthermore, incorporation of only 0.5 wt% SAP into soil improved soil water retention and promoted maize growth under drought conditions, increasing plant height and root length compared with the untreated control. These results demonstrate that solvent-free mechanochemical processing provides an effective and environmentally friendly strategy for producing bio-based SAPs with promising potential for sustainable agricultural water management.
Diabetic wounds are prone to bacterial infection and difficult to heal due to chronic inflammation and hyperglycemic microenvironment. Here we developed a novel bioactive hydrogel with multifunctional tunable properties, including biocompatibility, pH-response, anti-inflammatory activity, and the ability to promote diabetic wound healing. The injectable and self-healing hydrogel was prepared by cross-linking sulfated oxidized sodium alginate (S-OSA) with adipic dihydrazide (ADH) and subsequently loading with the angiogenic drug desferrioxamine (DFO). Under acidic microenvironment in diabetic wounds during the early stage, the hydrogel presented a pH-responsive and sustained release of DFO due to unstable acylhydrazone bonds. The hydrogel also exhibited good cytocompatibility and hemocompatibility. Furthermore, the in vivo experiments demonstrated that the hydrogel significantly promoted diabetic wounds healing by reducing the inflammatory response, accelerating collagen deposition, and promoting vascular regeneration. These findings suggested that sulfated alginate-based hydrogel holds considerable promise for treating diabetic wounds complicated by chronic inflammation.
The low degradation efficiency of lignocellulose during donkey manure composting restricts its humification. Manganese dioxide-modified biochar (MBC) can strengthen this process, whereas its dose effect remains unclear. This study investigated the effects and regulatory mechanisms of MBC levels (5% MBC1, 10% MBC2 and 15% MBC3) on lignocellulose degradation and humification during donkey manure composting. The results showed humus content followed the order: MBC1/MBC2 > CK > MBC3 (p<0.05), implying that an appropriate dosage of MBC promoted humification, while an excessively high dosage inhibited it. All MBC groups markedly enhanced lignocellulose degradation rate. MBC1 yielded the highest cellulose degradation rate (45.20%), whereas MBC3 attained maximum hemicellulose and lignin degradation rates (52.30% and 43.25%), attributable to varied lignocellulase activities under different MBC dosages. Two-dimensional correlation spectroscopy revealed that with increasing MBC addition rate, the variation order of fluorescence peaks of dissolved organic matter was: C1/210 nm>C1/255 nm>C2/200 nm>C2/290 nm; and C1/210 nm>C3/260 nm>C3/325 nm>C2/290 nm. Core microbial community analysis demonstrated that MBC1 and MBC2 significantly enhanced the diversity, relative abundance and functional diversity of core bacteria related to lignocellulose degradation and humus synthesis. Mantel test and partial least squares structural equation model confirmed that MBC coordinately regulated humification through biotic and abiotic pathways by modifying composting microenvironment. Considering economic cost and comprehensive efficiency, MBC1 was identified as the optimal dosage. This study provides theoretical basis and technical parameter guidance for MBC application in the composting of lignocellulose-rich materials.
Biodegradable materials with active and intelligent functionalities have attracted increasing interest as sustainable alternatives to conventional food packaging. This study developed and characterized thermoplastic starch (TPS)/gelatin films containing curcumin (Cur) as a pH-sensitive indicator, tea tree essential oil (TTO) as an active agent, and kombucha bacterial cellulose (KBC) as a natural emulsifier. KBC was purified, dried, and ultrasonicated, producing a heterogeneous micro/nanocellulose suspension (39.1-139.9 nm). The addition of gelatin substantially increased film stiffness, with Young's modulus increasing from 1.06 to 69.10 MPa and elongation at break decreasing from 583.94% to 25.93%, whereas the incorporation of KBC partially restored tensile strength to 2.88 MPa. KBC also improved water resistance by reducing solubility from 23.0% to 10.7% and increasing the water contact angle from 64.4° to 70.6°. The films exhibited a transparency index of approximately 4.0%, intense yellow coloration, and color transition from yellow to orange at pH ≥ 9. Although antimicrobial activity against Escherichia coli was limited, TTO increased DPPH radical scavenging activity from 44.75% to 52.55%, and storage tests with chicken samples showed color changes after 7 days of refrigerated storage.
Parkinson's disease (PD) is a synucleinopathy characterized by the accumulation of alpha-synuclein (αS) amyloid aggregates and loss of dopaminergic neurons. Evidence suggests that PD originates in intestine and progresses to brain via the vagus nerve. Thus, initially, the potential of orally-fed αS pre-formed fibrils (PFF) to induce PD in the wild-type Drosophila melanogaster is explored, where the findings corroborate the hypothesis of retrograde transport of infection from gut-to-brain, and exhibit PD-like symptoms, including impaired motor and non-motor symptoms, and degeneration of dopaminergic neurons. However, the PD flies, when transferred to green-synthesized zinc oxide nanoparticle surface-adsorbed αS nanoformulation (NF)-supplemented feed, show respite from progressive PD by restoring the retromer complex expression that induces the autophagic clearance of accumulated pathological PFF and ameliorating the oxidative stress and inflammation. Overall, the findings demonstrate therapeutic potential of the NF against the progressive PD.
The rapid accumulation of biological macromolecule data has created an urgent need for computational methods capable of characterizing the functional roles of macromolecular targets in complex therapeutic systems. Traditional Chinese medicine represents a typical scenario, in which multiple herbal components may coordinately regulate diverse protein targets through multi-component and multi-target mechanisms. However, existing methods often fail to jointly integrate traditional medicine knowledge, modern biomedical associations, and the functional context of biological targets, limiting systematic identification and mechanistic interpretation of herb-macromolecular target interactions (HTIs). Here, we propose LLM-HTI, a large language model (LLM)-driven graph learning framework with adaptive parameter updating based on a Traditional Chinese and Western medicine knowledge graph (TWKG), for predicting potential interactions between herbs and biological macromolecular targets. LLM-HTI extracts latent semantic representations of herb-target associations using LLMs and integrates them with knowledge graph topology, enabling joint characterization of herbs, macromolecular targets, and their functional relationships. The framework further introduces a gradient-guided adaptive parameter updating mechanism to dynamically select important parameter subsets, improving training stability and optimization efficiency. In addition, gastrointestinal surgeons independently assessed the top-ranked candidate targets for disease relevance, biological plausibility, clinical actionability, and translational priority to provide a clinician-guided evaluation of their medical relevance. These benchmark and case-study results demonstrate that LLM-HTI supports macromolecular target function analysis and herb-target mechanism discovery, while clinician-guided assessment further highlights medically relevant candidates for translational follow-up. Our data and code are publicly available at https://github.com/sisyyuan/LLM-HTI.
The growing environmental concerns on petroleum-based packaging materials have prompted substantial research into biodegradable alternatives. Here, we developed functional composite films through integrating holocellulose extracted from corn stalks in 65% LiBr aqueous solution with sodium alginate (SA), ε-polylysine (ε-PL), and phycocyanin (PC). The HSL8C film with 2% holocellolose, 15%SA, 0.8% ε-PL, and 1.5% PC exhibited a 57.4% DPPH radical scavenging activity, indicating superior antioxidant capacity. Moreover, these holocellulose-based films containing ε-PL and PC all demonstrated good mechanical properties, hydrophobicity, and gas barrier performances. Furthermore, the embedded PC enabled the film with excellent performances in strawberry preservation and visual monitoring of shrimp freshness. In this study, holecellulose from corn stalks were successfully used to prepare multifunctional prevention films, which provides a new approach for waste biomass in food packaging.
As naturally derived polymeric materials, chitosan and its derivatives exhibit considerable promise in food preservation, owing to their biodegradability, non-toxicity, structural tunability, and favorable mechanical properties. This review critically surveys recent progress in chitosan-based food preservation materials, with emphasis on preparation strategies, performance modulation, smart packaging functionalities, and prospective applications. The sources and intrinsic physicochemical characteristics of chitosan are examined, alongside various functionalization routes, including physical blending, chemical modification, and derivative synthesis. The systematic discussion then focuses on how these modification strategies-either independently or synergistically-regulate the key performance parameters of chitosan-based films and coatings, such as mechanical strength, water vapor and gas barrier properties, antibacterial and antioxidant activities, thermal stability, optical transparency, and biodegradability. Special attention is given to the emerging role of intelligent packaging in modern food preservation, and the mechanisms by which chitosan-based materials enable real-time, visual monitoring of food freshness through the integration of pH-sensitive dyes or volatile amine sensors are analyzed in detail. Future directions for chitosan and its derivatives in this field are outlined, with particular focus on their integration into smart packaging systems, and prioritized research avenues are proposed for further performance optimization, industrial scale-up, and commercialization. This review aims to provide a valuable reference for the development of efficient, sustainable, and intelligent food packaging solutions.
Bamboo, as a renewable biomass resource, presents significant potential for sustainable food packaging applications. In this study, cellulose nanofibrils were extracted from bamboo powder via sequential acid/alkali purification, TEMPO oxidation, and high-intensity ultrasonication. The resulting bamboo oxidized nanocellulose (BONC) was fabricated into aerogels via ice-templating and into films via casting to systematically investigate their fundamental properties. Purification effectively increased cellulose content from 56.29% to 95.71% by removing lignin and hemicellulose, while preserving the cellulose I crystalline structure. Oxidation enhanced dispersion and reduced the average fibril diameter from 13.45 nm (BNC) to 7.38 nm (BONC). For aerogels, increasing suspension concentration elevated density and compressive strength while reducing porosity. Lower freezing temperatures (-196 °C) yielded finer, more uniform pores, enhancing thermal insulation and structural integrity; conversely, directional freezing (DF) induced anisotropic architectures with superior axial mechanical strength but inferior thermal insulation. Notably, the high porosity (> 99%) and interconnected channels of aerogels resulted in excessive gas permeability and water absorption, precluding their standalone use as modified atmosphere layers. In contrast, BONC films exhibited concentration-dependent barrier properties, with the 1.0 wt% film reducing O₂ to 18.9% and increasing CO₂ to 3.67%. Therefore, the two forms of packaging materials can serve different purposes. These results establish a fundamental understanding of processing-structure-property relationships in bamboo-derived nanocellulose materials and lay an experimental foundation for the development of high-performance food packaging materials.
Gram-negative bacteria rely on the β-barrel assembly machinery (BAM) for the biogenesis of their outer membrane proteins (OMPs). In most bacterial species, the BAM complex consists of BamA together with several accessory proteins, including BamD, a highly conserved and indispensable component. However, no BAM complex components have previously been recognized in Treponema pallidum subsp. pallidum. By integrating phylogenetic analysis, AlphaFold 3-based structural prediction, and biochemical validation, we identified Tp0625 as a previously unrecognized BamD-like protein of the T. pallidum BAM system. Tp0625 binds directly to the POTRA domain of BamA (Tp0326), with preferential interaction involving the POTRA5-containing region, and forms a stable complex stabilized by extensive electrostatic interactions. Biophysical analysis reveals that Tp0625 binds BamA with moderate affinity (KD = 3.28 μM), and structural comparison shows that Tp0625 retains a conserved tetratricopeptide repeat (TPR) fold despite low sequence identity and a reduced number of TPR domains. These results offer evidence for a putative BamD-like protein in T. pallidum and support the existence of a conserved but simplified BAM complex in this pathogen. Our study establishes a structure-guided strategy for discovering divergent homologs of essential macromolecules, and expands our understanding of how spirochaetes maintain outer membrane integrity without a full complement of accessory proteins.
Polyethylene glycol (PEG) surface modification of protein-based nanoparticles is widely used to enhance colloidal stability, with potential applications in drug delivery. Despite its widespread use, the influence of PEG molecular weight on the behavior of PEG decorated zein nanoparticles remains insufficiently understood. Here, we investigate how PEG MW and PEG-to-zein ratio governs the structural and physicochemical properties of zein nanoparticles. Nanoparticles functionalized with PEG of 8, 20, and 35 kDa were characterized using a multiscale approach combining nanoscale analysis (particle size, zeta potential, FT-IR 2D-COS, titration, and thermogravimetric analysis) with thin-film surface characterization (water contact angle, roughness and atomic force microscopy). All formulations exhibited sizes of approximately 200 nm, low polydispersity, and similar surface charge (-45 mV), indicating preserved colloidal integrity across systems. However, PEG molecular weight and PEG-to-zein ratio were associated with differences in interfacial organization of PEG decorated zein nanoparticles. In addition, PEG 8 kDa enhanced surface hydrophilicity and hydroxyl exposure, suggesting a higher surface PEG density, whereas PEG 35 kDa was associated with more ordered interfacial features with enhanced colloidal and thermal stability. Notably, PEG 20 kDa provided the best compromise between surface coverage and stability. Overall, PEG molecular weight and PEG-to-zein ratio emerge as key designs for tuning the properties of zein nanoparticles, enabling precise control over structure, stability, and surface functionality through a simple molecular design strategy.
Triple-negative breast cancer (TNBC) responds poorly to immunotherapy, in part because its hyaluronic acid (HA)-rich and immunosuppressive tumor microenvironment restricts drug penetration and antitumor immune activation. Here, we developed an injectable alginate hydrogel platform (ICG-LNP@ALG-H) for localized co-delivery of hyaluronidase (HAase) and indocyanine green (ICG)-functionalized lipid nanoparticles (LNPs) carrying messenger RNA (mRNA) encoding interleukin-12 (IL-12) and granulocyte-macrophage colony-stimulating factor (GM-CSF). After administration into the postoperative tumor bed, the hydrogel formed an in situ depot that enabled sustained local retention and release. HAase degraded the HA-rich stromal matrix to enhance nanoparticle penetration, while near-infrared (NIR)-activated ICG generated reactive oxygen species through a photodynamic effect, promoting endosomal escape and improving intracellular mRNA delivery and cytokine expression. This platform integrated stromal remodeling, photoactivated intracellular delivery, and local immunostimulation in a single controlled-release system. In a postoperative 4 T1 TNBC recurrence model, ICG-LNP@ALG-H reduced local recurrence and elicited coordinated local and systemic immune responses, as indicated by enhanced intratumoral IL-12 expression and CD8+ T-cell infiltration, together with increased splenic NK-cell frequency, dendritic-cell maturation, and M1-like macrophage polarization. Short-term safety assessments revealed no overt abnormalities under the tested conditions. These results show that localized delivery of matrix-remodeling and immunostimulatory cargoes can address both stromal and intracellular barriers to mRNA therapy, supporting ICG-LNP@ALG-H as a locoregional controlled-release strategy for postoperative immunotherapy of stromal-rich solid tumors.
The extracellular matrix (ECM) is a noncellular structure component that provides mechanical support and mediates chemical and physical guidance for cellular behaviors. Hydrogels are typical ECM-mimicking materials, which are intricately associated with cellular self-organization. This study pioneers a composite hyaluronic acid (HA) hydrogel system with micropatterned interfaces that directs mesenchymal cells to self-organize into 3D hollow spheroids-unachievable in conventional homogeneous hydrogels. By designing rectangular groove interfaces between stiffness-differentiated hydrogel domains (cell-laden soft gel within grooves of cell-free stiff gel), we establish a spatiotemporally regulated niche for multicellular morphogenesis. The experimental findings reveal that 3D hollow multicellular spheroids with large internal cavities (100-250 μm in diameter) preferentially form adjacent to the engineered groove interfaces. Computational simulations reveal that the self-formation of hollow spheroids is mediated by the designed geometry of the hydrogel interface separating the sub-domains with differing stiffness. Hydrogel sub-domains with distinct mechanical properties and tailored sizes exhibit differential biomolecular diffusion and cell migration kinetics, thereby establishing a complex spatiotemporal regulation of the reaction and diffusion processes of biomolecules and cells. Experimental data align with our activator-inhibitor-substrate (AIS) model, demonstrating that interfacial geometry controls reaction-diffusion dynamics to induce cavity formation. This platform enables the on-demand fabrication of 3D tissue analogues with luminal structures, laying a foundation for advancing organoid engineering and pathological modeling.
Multifunctional finishing of textiles often relies on various chemical auxiliaries to achieve modification, which involves complicated procedures and poses environmental and health risks. In this study, ε-polylysine (ε-PL) was introduced into zein molecules using genipin (GNP) as a crosslinking agent to prepare colored recombinant zein (ε-PL-zein). The structure of ε-PL-zein was characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Fourier transform infrared (FTIR) spectroscopy, circular dichroism (CD) spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy and 1H nuclear magnetic resonance (1H NMR) spectroscopy. The results confirmed the successful grafting of ε-PL onto zein. After the grafting modification, the molecular weight of the protein increased significantly, its conformation was altered, and both the amino group content and the positive charge on the molecular surface were enhanced. Stable colored zein-based nanoparticles with an average particle size of approximately 200 nm were obtained via the antisolvent method and subsequently applied onto wool fabric in a single step, yielding multifunctional colored wool fabric with excellent antibacterial performance (>99% antibacterial rate against Escherichia coli and Staphylococcus aureus) and good anti-felting property (felting shrinkage rate of 4.00 ± 0.25%). Moreover, the treated fabrics maintained favorable color fastness and mechanical properties. The findings of this study provide an efficient and eco-friendly strategy for the development of multifunctional textile auxiliaries.
Gastrointestinal intolerance and limited intestinal residence remain important challenges in the long-term oral use of metformin (MET) for type 2 diabetes mellitus (T2DM). Although liposomal encapsulation can improve drug delivery, unmodified MET-encapsulated liposomes remain vulnerable to gastrointestinal disruption and premature leakage, which undermines their therapeutic potential. To address this limitation, Agaricus bisporus-derived chitosan (ACS) was employed as a bioactive macromolecular coating to construct MET-encapsulated liposomes (MET-LP). The ACS coating reversed the surface charge of MET-LP, improved colloidal dispersion, and enhanced storage stability, with 0.5% ACS-modified MET-encapsulated liposomes (A-M-L) retaining 83.1% encapsulation efficiency after 21 days at 4 °C. In T2DM mice, 1.0% A-M-L produced stronger glycemic control, lowering fasting blood glucose from 14.3 to 8.6 mmol/L, reducing HbA1c by approximately 32.9%, and decreasing the area under the curve (AUC) of the oral glucose tolerance test (OGTT) by 37.7%. Moreover, A-M-L improved serum lipid profiles and hepatic oxidative-stress-related indicators and was associated with lower ileal inflammatory cytokine levels and better-maintained gastrointestinal tissue morphology in T2DM mice. ACS modification also enhanced the intestinal retention of labelled liposomal carriers, as indicated by a 233.3% higher ileal fluorescence intensity of 0.5% A-M-L than unmodified MET-LP in SD rats. Collectively, these findings indicate that ACS modification improved the formulation stability, intestinal retention of labelled liposomal carriers, and hypoglycemic performance of MET-encapsulated liposomes.
Intestinal mucositis is one of the most debilitating side effects of chemotherapeutic agents. Angelica sinensis polysaccharide (ASP), the crucial active ingredient of Angelica sinensis, has been reported to possess anti-colitis activity. However, the efficacy of ASP against chemotherapy-induced intestinal mucositis (CIM) remain to be clarified. The aim of this study using Drosophila melanogaster and mouse models was to investigate the potential effect of ASP on intestinal mucositis and its underlying mechanism. ASP significantly alleviated overall physiological and intestinal damage caused by CPT-11 in adult flies, including increased survival rate and intestinal length, improved digestive capacity, restored intestinal acid-base balance and reduced death of intestinal epithelial cells. NIR imaging indicated that ASP was absorbed through the intestine and metabolized via the hepatic and renal systems in mice. Furthermore, ASP reduced intestinal damage and restored the intestinal barrier function in CPT-11 treated mice, including increased intestinal length, elevated levels of ZO-1 and an increased number of goblet cells. Mechanistically, ASP markedly down-regulated the over-activated innate immunity by inhibiting the Toll-IMD and TLR4/NF-κB/MyD88 signaling pathways in CPT-11 induced flies and mice. Besides, ASP also exerted a protective effect against structural damage to the spleen induced by CPT-11. Moreover, ASP ameliorated gut microbiota imbalances and increased the levels of short-chain fatty acids (SCFAs), particularly propionate and butyrate. Fecal microbiota transplantation (FMT) further confirmed that ASP could modulate gut microbiota and protect against intestinal mucositis in mice. Collectively, these results demonstrate that ASP effectively ameliorates CIM and has the potential to serve as a novel adjunctive therapy to CPT-11.
Selenium-enriched polysaccharides (Se-Ps) have attracted growing interest as promising antitumor agents; however, the potential of Pleurotus nebrodensis (PN) mycelium as a biotransformation carrier for Se-Ps production remains unexplored. This study aimed to develop a mycelial culture system for Se-Ps production and to elucidate their anti-breast cancer mechanisms. Selenium-enriched PN mycelia were obtained by supplementing the medium with sodium selenite at optimized concentration of 50 mg/L. Two purified Se-Ps fractions, Se-PNP-1 and Se-PNP-2, were isolated via water extraction-alcohol precipitation followed by DEAE-52 chromatography. Structural analyses confirmed selenium incorporation and revealed that Se-PNP-2, with a higher selenium content, exhibited a lower molecular weight and random coil conformation, which correlated with its superior bioactivity. In vitro, Se-PNP-2 dose-dependently suppressed 4 T1 cell proliferation (IC₅₀ = 292.4 μg/mL), migration, and invasion, and induced early apoptosis. In vivo, oral administration of Se-PNP significantly inhibited orthotopic 4 T1 tumor growth without observable toxicity, comparable to cyclophosphamide. Mechanistically, Se-PNP indirectly remodeled the tumor immune microenvironment by increasing TNF-α and IFN-γ while suppressing IL-10 and TGF-β1, and upregulated the Bax/Bcl-2 ratio and cleaved Casp3/Parp levels, indicating activation of the mitochondrial apoptosis pathway. These findings establish mycelial biotransformation as a feasible strategy for producing bioactive Se-Ps and position Se-PNP as a promising candidate for breast cancer therapy, with dual direct cytotoxic and immunomodulatory actions.
