International Journal of Biological Macromolecules最新文献

We report a green, non-destructive, and highly effective extraction, dissolution, film casting and solidification technology for cottonseed proteins from cottonseed meals. Although cottonseed meals are protein-rich, with about 40 % of proteins, they are cheap with a price 20 % to 50 % lower than soybean meals due to their poor performance as feed and bioplastics and due to the limited efforts from the academia and industries. Our green and protective protein extraction technology provided an extraction yield of 89 % and purity of 92 % with minimal destruction to the protein backbones, better than those reported previously. Our green dissolution/casting technology provided proteins with maximized unfolding and entanglement. When cottonseed proteins were solidified to form bioplastics, our technology also enabled substantial recovery of cystine crosslinkages between protein molecules to maximize the properties of the final products. Using our technologies, cottonseed protein films from cottonseed meals have toughness higher than what have been reported in literature without adding plasticizers or reinforcement materials, therefore better property stability or shelf life. Our technology is also cost-effective and can potentially add values to the cotton industry.

With the increasing use of high-fat diets (HFD), fatty liver disease has become common in fish, and fucoidan is of interest as a natural sulfated polysaccharide with lipid-lowering activity. To explore the molecular regulatory mechanisms of fucoidan's alleviation of HFD-induced lipid deposition in liver, black seabream (Acanthopagrus schlegelii) was used to construct in vivo and in vitro HFD models. In vivo HFD stimulated the protein kinase RNA-like endoplasmic reticulum kinase (Perk) pathway, and up-regulated proliferator-activated receptor gamma (Pparγ) nuclear translocation and expression of lipogenic genes, while it down-regulated Ppar alpha (Pparα) nuclear translocation and expression of lipolytic genes. However, fucoidan reversed these effects of HFD and significantly alleviated HFD-induced lipid accumulation in liver. Moreover, after sirtuin 1 (sirt1) knockdown, these effects of fucoidan disappeared. In the in vitro HFD model, GSK2606414 (GSK)-specific inhibition of the Perk pathway, decreased Pparγ nuclear translocation and increased Pparα nuclear translocation. Overall, fucoidan mitigated HFD-induced, Perk pathway-mediated lipid deposition in the liver of black seabream by activating Sirt1. The findings provided a new prospect for the application of green polysaccharides in aquatic animal feeds.

Escherichia coli O111 serotype is a critical pathogenic E. coli strain that causes severe, potentially fatal complications. Despite its reported variation, only one structure of the O-antigen polysaccharide from E. coli O111 has been reported. Here, a substructure of the O-antigen from E. coli O111 was characterized using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry and NMR analysis. MALDI glycotyping revealed differing O-antigen repeating unit masses of Δm/z 787 and 828 in the E. coli strains and lipopolysaccharides from the O111 serogroup. This variation was caused by the replacement of the hexose residue with hexosamine in the repeating units, which was further confirmed by LIFT-TOF/TOF analysis. Structural elucidation of the O111 substructure by NMR analysis further demonstrated replacement of the hydroxyl group with an N-acetyl group on the terminal glucose residue of the O-antigen pentasaccharide repeating unit. To our knowledge, this study is the first to provide a detailed structural analysis of a new O-antigen substructure from the E. coli O111 serogroup.

In this work, we present the case of the G-quadruplex(G4)-forming aptamers we recently identified for the recognition of HMGB1, protein involved in inflammatory, autoimmune diseases and cancer. These aptamers were previously analyzed, without annealing them, after proper dilution of the stock solution in a pseudo-physiological buffer mimicking the extracellular environment where the protein exerts its pathological activity, and showed high thermal stability and nuclease resistance, good protein affinity and remarkable in vitro activity. These features were more marked for the aptamers forming dimeric, parallel G4 structures in solution. Herein, we fully characterized the same anti-HMGB1 aptamers after a standard annealing procedure performed on diluted samples. Notably, upon a thermal unfolding/folding cycle, these aptamers, and particularly the best ones in the not-annealed form, showed significant conformational switches compared to the same systems analyzed without annealing, forming exclusively monomeric G4 structures, featured by poor thermal and enzymatic stabilities, along with lower protein affinities. These results prove that, for these aptamers, analyzed in the chosen conditions, annealing at low concentration does not produce a beneficial effect in terms of favouring the most bioactive species.

Natural compounds like Curcumin with anti-cancer, anti-inflammatory and anti-bacterial properties are good target for drug development but its poor aqueous solubility, bioavailability, and low retention properties makes it a poor drug candidate in clinical settings. Here in this study, we have used an indole curcumin analogue (ICA) that has better bioavailability and enhanced permeability and retention (EPR) effect than curcumin. To make an active targeting drug we have designed folic acid conjugated chitosan-based nanoparticles encapsulating Indole curcumin analogue (CS-FA-ICA-np). The physical characteristics of CS-FA-ICA-np were evaluated by DLS, SEM, FTIR, XPS, XRD and TGA. Anti-cancer activity was analyzed using MTT, Fluorescence staining, Flow cytometry, comet assay, DNA fragmentation assay, wound healing, gelatin zymography, chick chorioallantoic membrane (CAM) assay and hemolysis assay. The size of CS-FA-ICA-nps were found to be 111 nm, and spherical in shape as observed in SEM. In-vitro assays show that CS-FA-ICA np has IC₅₀ of 90 μg/mL in MDA-MB-231, increases ROS concentration, arrests cell cycle in G2-M phase, reduces matrix metalloproteinase-9 (MMP-9) activity and initiates apoptosis in cancer cells. Our results indicate that encapsulation of ICA increases its anti-cancer effect, drug stability, enhanced drug delivery to cancer microenvironment.

This study presents fabrication and characterization of novel chamomile essential oil (CMO)/gallic acid-stabilized silver nanoparticles (gallic acid-nanosilver, GNS), embedded into polylactic acid (PLA)-based hybrid bilayer nanofibers (NFs). Where CMO was impregnated into polyvinyl alcohol (PVA)-polyethylene glycol (PEG) solution and electrospun simultaneously with PLA to obtain PLA/PVA-PEG-CMO NFs (PLA/CMO A2). Meanwhile, GNS were added to PVA-PEG-CMO and electrospun to obtain PLA/PVA-PEG-CMO-GNS NFs (PLA/CMO-GNS A3). Where pure PLA/PVA-PEG NFs were coded pure PLA/A1. Physicochemical properties of fabricated bilayer-NFs were performed using various approaches. Besides, porosity%, swelling, biodegradability, CMO release pattern, antioxidant, antibacterial activity and cytotoxicity were investigated. Study investigation revealed PLA-based bilayer NFs exhibited a biphasic release profile for impregnated CMO. Due to presence of GA, antioxidant property and biocompatibility of PLA/CMO-GNS A3 was superior compared to pure PLA/A1 and PLA/CMO A2. Antibacterial activity was enhanced in presence of CMO in PLA/CMO A2 than pure PLA/A1. Furthermore, addition of GNS in PLA/CMO-GNS A3 displayed highest antibacterial activity due to synergy of CMO/GNS. Finally, MTT assay with HFB4 fibroblasts demonstrated absence of cytotoxicity of bilayer-based NFs. Thus, study suggests that developed PLA/PVA-PEG NFs could be a promising candidate for tissue regeneration and food edible packaging in particular when impregnated with both CMO/GNS.

Osteoarthritis burdens patients due to the limited regenerative capacity of chondrocytes. Traditional cartilage repair often falls short, necessitating innovative approaches. Mesenchymal stem cells (MSCs) show promise for regeneration. Heparan sulfate glycosaminoglycans (HS-GAGs) regulate cellular functions, making them a target for cartilage repair. This study highlights how Heparinase III (HepIII) cleaves intact HS-GAGs in bone marrow-derived MSCs (BM-MSCs), enhancing their capabilities and specifically promoting chondrogenesis. HepIII-treated BM-MSCs cultured in a hanging drop device for three days, significantly increased cell number and aggregation into a cell sphere with early chondrogenesis. HepIII promoted BM-MSCs toward chondrogenesis, increasing type II collagen, intact HS-GAGs, and sulfated GAG content, while upregulating chondrogenic and heparan sulfate proteoglycan genes. Treatment with the TGF-β inhibitor (SB-431542) in HepIII-treated BM-MSCs demonstrated enhanced intrinsic transforming growth factor-β (TGF-β) signaling and fibronectin expression. This approach also boosted BM-MSC self-renewal, immunosuppressive potential, and modified acetylated histone signatures, offering a cost-effective strategy for cartilage repair by addressing inflammation, metabolic changes, and the high costs of traditional TGF-β methods. From the results, HepIII-treated BM-MSCs show potential for use in combination with other biopolymers as injectable gels to improve cartilage repair in osteoarthritis patients in the near future.

Surgical resection is an efficient treatment for cancerous tissues and uterine fibroids in the women uterus. However, the insufficiency of clinical interventions could result in tumor recurrence, and the defective tissues remained would cause intrauterine adhesions (IUAs) and further affect reproduction capacity. In this study, 3D printed hydrogel/poly(l-lactide-co-trimethylene carbonate) (PLLA-co-TMC, "PTMC" in short) core/shell scaffolds with NIR-tuned doxorubicin hydrochloride (DOX) and estradiol (E2) dual release were designed and fabricated for cancer therapy and uterine regeneration. Gelatin (Gel) and DOX were homogeneously mixed and then 3D printed to form Gel-DOX scaffolds. Gel-DOX scaffolds were then immersed in PTMC-PDA@E2 solution to fabricate Gel-DOX/PTMC-PDA@E2 core/shell scaffolds. Consequently, Gel-DOX/PTMC-PDA@E2 scaffolds could release DOX and E2 in a chronological manner, firstly delivering DOX assisted by phototherapy (PTT) to effectively kill Hela cells and then sustainably releasing E2 to promote uterine tissue regeneration. In vitro experiments showed that core/shell scaffolds exhibited excellent anticancer efficiency through the synergy of DOX release and hyperthermia ablation. Moreover, E2 could be sustainably released for over 28 days in vitro to promote the proliferation of bone marrow-derived mesenchymal stem cells (BMSCs). The novel Gel-DOX/PTMC-PDA@E2 core/shell scaffolds have therefore exhibited potential promise for the treatment of cancer therapy and uterine regeneration.

Tissue engineering has emerged as a promising substitute for traditional tissue repair methods. Nowadays, advancements in 3D printing technology have enabled the fabrication of customized scaffolds to support tissue regeneration. In the present study, a polylactic acid-polyvinylpyrrolidone 3D-printed scaffold containing 10 % forsterite was fabricated. Subsequently, lyophilized fucoidan microstructures loaded with sildenafil were filled the channels of this 3D-printed scaffold. The fabricated scaffold loaded with sildenafil was thoroughly characterized, revealing that 97.46 % of the loaded sildenafil was released in a sustained manner over 28 days. Furthermore, the biocompatibility of MG63 was evaluated through cell viability and adhesion tests. The findings indicated a direct and favorable influence on cell behavior. Based on the chicken chorioallantoic membrane assay, the fabricated scaffold significantly increases angiogenesis due to the sustained release of sildenafil. Moreover, in-vivo studies conducted on a rat model demonstrated that the 3D-printed scaffold was able to stimulate and accelerate the repair of calvarial defects within 8 weeks, and the amount of new bone tissue formation was significantly higher than that of other experimental groups. Based on the comprehensive in-vitro and in-vivo assessments, the scaffold with a macro- and microporous structure combined with the ability to release sildenafil is suggested as a potential candidate for repairing bone tissue, especially in the context of skull defects.