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1.
Mater Today Bio ; 26: 101031, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38558772

RESUMO

Developing a self-elastic sponge integrating active and passive hemostatic mechanisms for the effective management of uncontrolled coagulopathic hemorrhage remains a challenge. We here developed a chitosan-based sponge by integrating freeze-drying, chemical decoration of alkyl chains and phosphate groups, and physical loading of thrombin. The sponge exhibited high mechanical strength, self-elasticity, and rapid shape recovery. The sponge facilitated blood cell adhesion, aggregation, and activation through hydrophobic and electrostatic interactions, as well as accelerated blood clotting. The sponge exhibited higher efficacy than commercial gauze and gelatin sponge in managing uncontrolled hemorrhage from heparinized rat tail amputation, liver superficial injury, and liver perforating wound models. In addition, the sponge exhibited favorable biodegradability and biocompatibility. These findings revealed that the developed sponge holds great potential as a novel hemostat for effectively managing uncontrolled coagulopathic hemorrhage from superficial and perforating wounds.

2.
Front Microbiol ; 15: 1345478, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559346

RESUMO

Antimicrobial resistance is one of the largest medical challenges because of the rising frequency of opportunistic human microbial infections across the globe. This study aimed to extract chitosan from the exoskeletons of dead bees and load it with bee venom (commercially available as Apitoxin [Api]). Then, the ionotropic gelation method would be used to form nanoparticles that could be a novel drug-delivery system that might eradicate eight common human pathogens (i.e., two fungal and six bacteria strains). It might also be used to treat the human colon cancer cell line (Caco2 ATCC ATP-37) and human liver cancer cell line (HepG2ATCC HB-8065) cancer cell lines. The x-ray diffraction (XRD), Fourier transform infrared (FTIR), and dynamic light scattering (DLS) properties, ζ-potentials, and surface appearances of the nanoparticles were evaluated by transmission electron microscopy (TEM). FTIR and XRD validated that the Api was successfully encapsulated in the chitosan nanoparticles (ChB NPs). According to the TEM, the ChB NPs and the ChB NPs loaded with Apitoxin (Api@ChB NPs) had a spherical shape and uniform size distribution, with non-aggregation, for an average size of approximately 182 and 274 ± 3.8 nm, respectively, and their Zeta potential values were 37.8 ± 1.2 mV and - 10.9 mV, respectively. The Api@ChB NPs had the greatest inhibitory effect against all tested strains compared with the ChB NPs and Api alone. The minimum inhibitory concentrations (MICs) of the Api, ChB NPs, and Api@ChB NPs were evaluated against the offer mentioned colony forming units (CFU/mL), and their lowest MIC values were 30, 25, and 12.5 µg mL-1, respectively, against Enterococcus faecalis. Identifiable morphological features of apoptosis were observed by 3 T3 Phototox software after Api@ChB NPs had been used to treat the normal Vero ATCC CCL-81, Caco2 ATCC ATP-37, and HepG2 ATCC HB-8065 cancer cell lines for 24 h. The morphological changes were clear in a concentration-dependent manner, and the ability of the cells was 250 to 500 µg mL-1. These results revealed that Api@ChB NPs may be a promising natural nanotreatment for common human pathogens.

3.
Int J Nanomedicine ; 19: 3045-3070, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559447

RESUMO

Background: Diabetes Mellitus is a multisystem chronic pandemic, wound inflammation, and healing are still major issues for diabetic patients who may suffer from ulcers, gangrene, and other wounds from uncontrolled chronic hyperglycemia. Marshmallows or Althaea officinalis (A.O.) contain bioactive compounds such as flavonoids and phenolics that support wound healing via antioxidant, anti-inflammatory, and antibacterial properties. Our study aimed to develop a combination of eco-friendly formulations of green synthesis of ZnO-NPs by Althaea officinalis extract and further incorporate them into 2% chitosan (CS) gel. Method and Results: First, develop eco-friendly green Zinc Oxide Nanoparticles (ZnO-NPs) and incorporate them into a 2% chitosan (CS) gel. In-vitro study performed by UV-visible spectrum analysis showed a sharp peak at 390 nm, and Energy-dispersive X-ray (EDX) spectrometry showed a peak of zinc and oxygen. Besides, Fourier transforms infrared (FTIR) was used to qualitatively validate biosynthesized ZnO-NPs, and transmission electron microscope (TEM) showed spherical nanoparticles with mean sizes of 76 nm and Zeta potential +30mV. The antibacterial potential of A.O.-ZnO-NPs-Cs was examined by the diffusion agar method against Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). Based on the zone of inhibition and minimal inhibitory indices (MIC). In addition, an in-silico study investigated the binding affinity of A.O. major components to the expected biological targets that may aid wound healing. Althaea Officinalis, A.O-ZnO-NPs group showed reduced downregulation of IL-6, IL-1ß, and TNF-α and increased IL-10 levels compared to the control group signaling pathway expression levels confirming the improved anti-inflammatory effect of the self-assembly method. In-vivo study and histopathological analysis revealed the superiority of the nanoparticles in reducing signs of inflammation and wound incision in rat models. Conclusion: These biocompatible green zinc oxide nanoparticles, by using Althaea Officinalis chitosan gel ensure an excellent new therapeutic approach for quickening diabetic wound healing.


Assuntos
Althaea , Quitosana , Diabetes Mellitus , Nanopartículas Metálicas , Óxido de Zinco , Humanos , Animais , Ratos , Óxido de Zinco/química , Quitosana/química , Althaea/metabolismo , Interleucina-6 , Fator de Necrose Tumoral alfa , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Cicatrização , Anti-Inflamatórios/farmacologia , Inflamação , Flores , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
4.
Toxicol Res (Camb) ; 13(2): tfae050, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38559757

RESUMO

Background: Ehrlich ascites carcinoma (EAC) is a rapidly growing and undifferentiated tumor that can prompt oxidative stress and liver toxicity, whereas chitosan and Grifola Frondosa have widely recognized biological qualities. Therefore, our study designed to assess the potential ameliorative ability of chitosan nanoparticles (CS NPs) and Grifola Frondosa nanoparticles (GF-loaded casein NPs) on EAC-induced hepatic injury in mice. Methods: A total of 60 female albino mice were segregated into 6 groups (10 mice each), G1, control group; G2, CS NPs group; G3, GF-loaded casein NPs group; G4, EAC group; G5, EAC treated with CS NPs; G6, EAC treated with GF-loaded casein NPs. Results: According to the findings, EAC considerably increased serum activities of ALT, AST, ALP as well as LDL, cholesterol, and triglycerides levels coincided with marked decrease in albumin and total protein content in liver tissue. At the same time, it drastically lowered GSH levels and catalase activity while significantly elevating MDA levels. In addition, EAC caused DNA damage and apoptosis by decreasing Bcl-2 while increasing p53 expressions. However, either CS NPs or GF-loaded casein NPs therapy improved liver architecture and functioning, increased antioxidant parameters, and prevented hepatocyte death in EAC mice. Conclusions: Our findings concluded that CS NPs and GF-loaded casein NPs have insulating functions against EAC-induced hepatic damage in mice.

5.
Heliyon ; 10(7): e28452, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38560170

RESUMO

Considering biosafety concerns and survivability limitations of probiotics (PRO) under different stresses, application of postbiotics and encapsulated PRO has received considerable attentions. Accordingly, the objective of the present study was to investigate the postbiotic capabilities of a potential PRO yeast isolate and the effect of encapsulation with alginate (Alg) and chitosan (Ch) on its survival under SGI conditions. Sequencing results of the PCR products led to the identification of Saccharomyces cerevisiae as the selected potential PRO yeast isolated from wheat germ sourdough. High survival of the isolate under simulated gastrointestinal (SGI) conditions (95.74%), its proper adhesion abilities, as well as its potent inhibitory activity against Listeria monocytogenes (75.84%) and Aspergillus niger (77.35%) were approved. Interestingly, the yeast cell-free supernatant (CFS) showed the highest antioxidant (84.35%) and phytate-degrading (56.19%) activities compared to the viable and heat-dead cells of the isolate. According to the results of the HPLC-based assay, anti-ochratoxin A (OTA) capability of the dead cells was also significantly (P < 0.05) higher than that of the viable cell. Meanwhile, the yeast CFS had no anti-OTA and antimicrobial activities against the foodborne bacteria and fungi tested. Further, microencapsulation of the yeast isolate in Alg beads coated layer-by-layer with Ch (with 77.02% encapsulation efficacy and diameter of 1059 µm based on the field emission scanning electron microscopy analysis) significantly enhanced its survivability under SGI conditions in comparison with the free cells. In addition, electrostatic cross-linking between negatively charged carboxylic groups of Alg and positively charged amino groups of Ch was verified in accordance with Fourier transform infrared and zeta potential data. Human and/or industrial food trials in future are needed for practical applications of these emerging ingredients.

6.
Heliyon ; 10(7): e28648, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38560230

RESUMO

Graphene oxide and chitosan composite material using as a high-efficiency and low-cost granular adsorbent for methylene blue removal was fabricated via self-assembling method. The effects of pH value, contact time, initial concentration, adsorbent dose, temperature, and recyclic stability on the adsorption performance of methylene blue in aqueous solution were investigated in detail. Desorption process with the effects of solvents, contact time, and temperature were also conducted carefully in this study. The adsorption kinetics and adsorption isotherm of dye adsorption process showed that dye adsorption process was fitted to the pseudo-second-order kinetic model and the Freundlich adsorption isotherm, indicating a physical adsorption process with multilayer adsorption. The intra-particle diffusion model indicated that the dye adsorption by the granular adsorbent was strongly happened during the first 4 h. The thermodynamic study showed that the adsorption was a spontaneous and exothermic process and dye ions were condensed onto the surface of adsorbent. The maximum adsorption capacity of dye on the granular adsorbent was calculated as 951.35 mg/g and the adsorbent could maintain its adsorption performance after six cycles. In general, this study provided an efficient, cost-effective, and recyclable the granular adsorbent for dye separation from aqueous solution.

7.
Cureus ; 16(2): e55193, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38562272

RESUMO

Wound healing is an evolving and intricate technique that is vital to the restoration of tissue integrity and function. Over the past few decades, chitosan a biopolymer derived from chitin, became known as an emerging biomaterial in the field of healing wounds due to its distinctive characteristics including biocompatibility, biodegradability, affinity to biomolecules, and wound-healing activity. This natural polymer exhibits excellent healing capabilities by accelerating the development of new skin cells, reducing inflammation, and preventing infections. Due to its distinct biochemical characteristics and innate antibacterial activity, chitosan has been extensively researched as an antibacterial wound dressing. Chronic wounds, such as diabetic ulcers and liver disease, are a growing medical problem. Chitosan-based biomaterials are a promising solution in the domain of wound care. The article analyzes the depth of chitosan-based biomaterials and their impact on wound healing and also the methods to enhance the advantages of chitosan by incorporating bioactive compounds. This literature review is aimed to improve the understanding and knowledge about biomaterials and their use in wound healing.

8.
Biomater Adv ; 160: 213833, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38564997

RESUMO

Conventional chemotherapy and poor targeted delivery in brain cancer resulting to poor treatment and develop resistance to anticancer drugs. Meanwhile, it is quite challenging to diagnose/detection of brain tumor at early stage of cancer which resulting in severity of the disease. Despite extensive research, effective treatment with real-time imaging still remains completely unavailable, yet. In this study, two brain cancer cell specific moieties i.e., AS1411 aptamer and RGD are decorated on the surface of chitosan-PLGA nanoparticles to improve targeted co-delivery of docetaxel (DTX) and upconversion nanoparticles (UCNP) for effective brain tumor therapy and real-time imaging. The nanoparticles were developed by a slightly modified emulsion/solvent evaporation method. This investigation also translates the successful synthesis of TPGS-chitosan, TPGS-RGD and TPGS-AS1411 aptamer conjugates for making PLGA nanoparticle as a potential tool of the targeted co-delivery of DTX and UCNP to the brain cancer cells. The developed nanoparticles have shown an average particle size <200 nm, spherical in shape, high encapsulation of DTX and UCNP in the core of nanoparticles, and sustained release of DTX up to 72 h in phosphate buffer saline (pH 7.4). AS1411 aptamer and RGD functionalized theranostic chitosan-PLGA nanoparticles containing DTX and UCNP (DUCPN-RGD-AS1411) have achieved greater cellular uptake, 89-fold improved cytotoxicity, enhanced cancer cell arrest even at lower drug conc., improved bioavailability with higher mean residence time of DTX in systemic circulation and brain tissues. Moreover, DUCPN-RGD-AS1411 have greatly facilitated cellular internalization and higher accumulation of UCNP in brain tissues. Additionally, DUCPN-RGD-AS1411 demonstrated a significant suppression in tumor growth in brain-tumor bearing xenograft BALB/c nude mice with no impressive sign of toxicities. DUCPN-RGD-AS1411 has great potential to be utilized as an effective and safe theranostic tool for brain cancer and other life-threatening cancer therapies.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38561537

RESUMO

Reticular chemistry, exemplified by metal-organic frameworks (MOFs), has proven invaluable in creating porous materials with finely tuned structures to address critical global energy and environmental challenges. In this context, the need for efficient carbon dioxide (CO2) capture and utilization has taken center stage. One promising approach involves the integration of MOFs into polymer matrix to develop mixed matrix membranes (MMMs). In this work, cerium-based MOFs (Ce-MOF) were selected due to their robust CO2 capture capabilities, while chitosan (CS) was chosen as the polymer matrix due to its reasonably good selectivity and balanced CO2 permeance for the development of MMMs for CO2/N2 (20/80 vol%) separation. A comprehensive suite of analytical techniques, including FTIR, XRD, FESEM, XPS, TGA, EDX, FETEM, and BET, was applied for precise characterization of both the MOF and MMMs. Various operational parameters, such as Ce-MOF content and temperature, were systematically explored to investigate the CO2 capture efficiency of the synthesized MMMs. The results revealed that the optimized Ce-MOF-embedded CS MMMs consistently outperformed the bare CS membranes.

10.
Int J Biol Macromol ; 266(Pt 2): 131277, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38565366

RESUMO

Bacteria-infected wound healing has attracted widespread attention in biomedical engineering. Wound dressing is a potential strategy for repairing infectious wounds. However, the development of wound dressing with appropriate physiochemical, antibacterial, and hemostatic properties, remains challenging. Hence, there is a motivation to develop new synthetic dressings to improve bacteria-infected wound healing. Here, we fabricate a biocompatible sponge through the covalent crosslinking of collagen (Col), quaternized chitosan (QCS), and graphene oxide (GO). The resulting Col-QCS-GO sponge shows an elastic modulus of 1.93-fold higher than Col sponge due to enhanced crosslinking degree by GO incorporation. Moreover, the fabricated Col-QCS-GO sponge shows favorable porosity (84.30 ± 3.12 %), water absorption / retention (2658.0 ± 113.4 % / 1114.0 ± 65.7 %), and hemostasis capacities (blood loss <50.0 mg). Furthermore, the antibacterial property of the Col-QCS-GO sponge under near-infrared (NIR) irradiation is significantly enhanced (the inhibition rates are 99.9 % for S. aureus and 99.9 % for E. coli) due to the inherent antibacterial properties of QCS and the photothermal antibacterial capabilities of GO. Finally, the Col-QCS-GO+NIR sponge exhibits the lowest percentage of wound area (9.05 ± 1.42 %) at day 14 compared to the control group (31.61 ± 1.76 %). This study provides new insights for developing innovative sponges for bacteria-infected wound healing.

11.
Int J Biol Macromol ; 266(Pt 2): 131289, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38570002

RESUMO

Intranasal vaccination offers crucial protection against influenza virus pandemics. However, antigens, especially subunit antigens, often fail to induce effective immune responses without the help of immune adjuvants. Our research has demonstrated that a polyelectrolyte complex, composed of curdlan sulfate/O-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (CS/O-HTCC), effectively triggers both mucosal and systemic immune responses when administrated intranasal. In this study, stable nanoparticles formed by curdlan-O-HTCC conjugate (CO NP) were prepared and characterized. Furthermore, the efficacy of CO NP was evaluated as a mucosal adjuvant in an intranasal influenza H1N1 subunit vaccine. The results revealed that CO NP exhibits uniform and spherical morphology, with a size of 190.53 ± 4.22 nm, and notably, it remains stable in PBS at 4 °C for up to 6 weeks. Biological evaluation demonstrated that CO NP stimulates the activation of antigen-presenting cells (APCs), including macrophages and dendritic cells (DCs), both in vitro and in vivo. Furthermore, intranasal administration of CO NP effectively elicits cellular and humoral immune responses, notably enhancing mucosal immunity. Thus, CO NP emerges as a promising mucosal adjuvant for influenza subunit vaccines.

12.
Heliyon ; 10(7): e28641, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38571597

RESUMO

In alignment with the sustainable development goals (SDGs), recent trends in water management have been directed toward using environmentally friendly bio-based materials for removing contaminants. In this work, we prepared a biocomposite of chitosan (CS) intercalated into acid activated calcium bentonite (Bent). A thermally stable mesoporous CS-Bent composite was prepared with a zeta potential of 15.5 to -34.4 mV in the pH range of 2.22-10. The biocomposite successfully removed up to 99.2% and 50 mg/g of the antibiotic ciprofloxacin HCl (CPX) at pH 5.5 via electrostatic and hydrogen bonding forces. In a multi-component aqueous system of heavy metal and CPX, the composite was more selective to CPX than to the heavy metals and removal of CPX in this system was comparable to that in a single-component system. The composite also maintained its high adsorption efficiency in NaCl solutions which makes it suitable for treating fresh and saline solutions. The combination of CS and bent produced a biodegradable eco-friendly composite characterized with good thermal and surface properties along with efficient and selective adsorption performance.

13.
Food Chem ; 449: 139168, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38574521

RESUMO

A robust biocompatible solid-phase microextraction (SPME) fiber, so-called Ti/APTS/GA/CS, was prepared by chemical bonding of cross-linked glutaraldehyde-chitosan to the surface of a titanium wire using APTS. The fiber was applied for sampling of phytohormones in plant tissues, followed by HPLC-UV analysis. The structure and morphology of the fiber coating was investigated by FT-IR, SEM, EDX, XRD, and TGA techniques. A Box-Behnken design was implemented to optimize the experimental variables. The calibration graphs were linear over a wide linear range (0.5-200 µg L-1) with LODs over the range of 0.01-0.06 µg L-1. The intra-day and inter-day precisions were found to be 1.3-6.3% and 4.3-7.3%, respectively. The matrix effect values ranged from 86.5% to 111.7%, indicating that the complex sample matrices had an insignificant effect on the determination of phytohormones. The fiber was successfully employed for the direct-immersion SPME (DI-SPME-HPLC) analysis of the phytohormones in cucumber, tomato, date palm, and calendula samples.

14.
Biopolymers ; : e23578, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38577865

RESUMO

Ocular drug delivery is constrained by anatomical and physiological barriers, necessitating innovative solutions for effective therapy. Natural polymers like hyaluronic acid, chitosan, and gelatin, alongside synthetic counterparts such as PLGA and PEG, have gained prominence for their biocompatibility and controlled release profiles. Recent strides in polymer conjugation strategies have enabled targeted delivery through ligand integration, facilitating tissue specificity and cellular uptake. This versatility accommodates combined drug delivery, addressing diverse anterior (e.g., glaucoma, dry eye) and posterior segment (e.g., macular degeneration, diabetic retinopathy) afflictions. The review encompasses an in-depth exploration of each natural and synthetic polymer, detailing their individual advantages and disadvantages for ocular drug delivery. By transcending ocular barriers and refining therapeutic precision, these innovations promise to reshape the management of anterior and posterior segment eye diseases.

15.
Vet World ; 17(2): 319-328, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38595659

RESUMO

Background and Aim: Irradiated chitosan can be used as a matrix for slow-release urea (SRU) production. This study aimed to (1) determine the optimal formulation of irradiated chitosan matrix for controlling nitrogen release and (2) evaluate the characteristics of SRU in vitro fermentation based on irradiated chitosan as a feed supplement. Materials and Methods: In the first phase of the investigation, four chitosan-based SRU formulations with varying amounts of acrylamide (3 and 5 g) and gamma irradiation (5 and 10 kGy) were evaluated. Scanning electron microscopy, Fourier transform mid-infrared spectroscopy, and ammonia release characteristics were used to observe morphological, functional group, and ammonia release characteristics. In the second phase of research, the most effective SRU formulation was utilized as a supplement to ruminant rations based on rice straw, sorghum straw, and alfalfa. Gas production, rumen fermentation characteristics, and methane gas production were observed in vitro. Results: On the basis of surface image analysis, the four SRU formulas generate a similar appearance. Compared with untreated urea, the SRU3 formula reduced the percentage of ammonia emission by 12.85%-27.64% after 24 h of incubation (p = 0.05), as determined by the first phase study. SRU3 became the basis for the second testing phase. The addition of SRU3 did not affect the optimal gas production in vitro. SRU3 treatment produced less gas than Optigen® treatment (p = 0.05). With regard to rumen fermentation and digestibility, Optigen® yielded better results than SRU3 (p = 0.05). However, the treatment with SRU3 resulted in reduced methane production compared to that in the control (p = 0.05). Conclusion: Irradiated chitosan as an SRU matrix may control the release of ammonia in the rumen medium. The SRU3 formulation is the most effective. The addition of SRU to rice straw-based rations reduces methane production without affecting in vitro digestibility.

16.
Biomater Adv ; 160: 213849, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38599041

RESUMO

Spheroids derived from human mesenchymal stem cells (hMSCs) are of limited use for cartilage regeneration, as the viability of the cells progressively decreases during the period required for chondrogenic differentiation (21 days). In this work, spheroids based on hMSCs and a lactose-modified chitosan (CTL) were formed by seeding cells onto an air-dried coating of CTL. The polymer coating can inhibit cell adhesion and it is simultaneously incorporated into spheroid structure. CTL-spheroids were characterized from a morphological and biological perspective, and their properties were compared with those of spheroids obtained by seeding the cells onto a non-adherent surface (agar gel). Compared to the latter, smaller and more viable spheroids form in the presence of CTL as early as 4 days of culture. At this time point, analysis of stem cells differentiation in spheroids showed a remarkable increase in collagen type-2 (COL2A1) gene expression (~700-fold compared to day 0), whereas only a 2-fold increase was observed in the control spheroids at day 21. These results were confirmed by histological and transmission electron microscopy (TEM) analyses, which showed that in CTL-spheroids an early deposition of collagen with a banding structure already occurred at day 7. Overall, these results support the use of CTL-spheroids as a novel system for cartilage regeneration, characterized by increased cell viability and differentiation capacity within a short time-frame. This will pave the way for approaches aimed at increasing the success rate of procedures and reducing the time required for tissue regeneration.

17.
Int Immunopharmacol ; 132: 112019, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38599099

RESUMO

OBJECTIVE: The current study aimed to assess the modulating effect of IL-2 encapsulated chitosan-nanoparticles (CSNPs) on the function of Treg cells through induction of type 1 diabetes (T1D). Treg cell function was monitored by the forkhead box P3 (FoxP3) and transforming growth factor beta (TGFß) levels, correlating them with blood glucose and serum insulin levels. MATERIALS AND METHODS: In this case-control study, a low dose of IL-2 (free and chitosan-loaded) was injected into a diabetic mice group. The levels of FoxP3 and TGF-ß 1 were assessed using Enzyme-Linked Immunosorbent Assay. In addition, blood glucose and serum insulin levels were determined. RESULTS: The mean glucose level decreased significantly after free rIL-2 or rIL-2 / CSNPs treatment. Meanwhile, the mean serum insulin level was significantly increased after treatment with free rIL-2 or rIL-2/CSNPs. The mean levels of FoxP3 and TGFß 1 were significantly increased with either free rIL-2 or rIL-2/CSNPs compared to the T1D untreated group (P < 0.001). In the treated mice group receiving free CSNPs, there was a significant negative correlation between glucose and insulin levels. Moreover, FoxP3 & TGFß 1 levels had a significant positive correlation. In treated mice groups with free rIL-2 and IL-2 CSNPs, there was a significant positive correlation between FoxP3 and glucose levels. A significant negative correlation was found after conducting a correlation between insulin level and FoxP3 in the T1D/ rIL-2 / CSNPs group. CONCLUSIONS: Low-dose IL-2 selectively modulates FoxP3 + Tregs, and TGFß 1 increases their levels. These results demonstrated that IL-2-free and chitosan-loaded nanoparticles can be therapeutic agents in T1D.

18.
Food Chem ; 449: 139240, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38599109

RESUMO

The study reports the efficacy of nanofabricated citronellal inside the chitosan biopolymer (NeCn) against Aspergillus flavus growth, aflatoxin B1 (AFB1) production, and active ingredient biodeterioration (Piperine) in Piper longum L. The prepared NeCn was characterized by Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), and Fourier Transform Infrared Spectroscopy (FTIR). The results revealed that the NeCn exhibited distantly improved antifungal (1.25 µL/mL) and AFB1 inhibition (1.0 µL/mL) compared to free Cn. The perturbances in membrane function, mitochondrial membrane potential, antioxidant defense system, and regulatory genes (Ver-1 and Nor-1) of AFB1 biosynthesis were reported as probable modes of action of NeCn. The NeCn (1.25 µL/mL) effectively protects the P. longum from A. flavus (78.8%), AFB1 contamination (100%), and deterioration of Piperine (62.39%), thus demonstrating its potential as a promising novel antifungal agent for food preservation.

19.
Eur J Pharm Biopharm ; : 114281, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38599299

RESUMO

Nattokinase (NK) is a thrombolytic enzyme extracted from natto, which can be used to prevent and treat blood clots. However, it is sensitive to the environment, especially the acidic environment of human stomach acid, and its effect of oral ingestion is minimal. This study aims to increase NK's oral and storage stability by embedding NK in microcapsules prepared with chitosan (CS) and γ-polyglutamic acid (γ-PGA). The paper prepared a double-layer NK oral delivery system by layer self-assembly and characterized its stability and in vitro simulated digestion. According to the research results, the bilayer putamen structure has a protective effect on NK, which not only maintains high activity in various environments (such as acid-base, high temperature) and long-term storage (60 days), but also effectively protects the loaded NK from being destroyed in gastric fluid and achieves its slow release. This work has proved the feasibility of the design of bilayer putamen structure in oral administration and has good fibrolytic activity. Therefore, the novel CS/γ-PGA microcapsules are expected to be used in nutraceutical delivery systems.

20.
Int J Biol Macromol ; : 131481, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38599431

RESUMO

We developed an effective and eco-friendly strategy using chitosan gel-molten salt to achieve high loading (2.23 At. %) of single Fe-NX as assistive active sites. These sites were combined with small NiCo alloy NPs distributed on porous carbon aerogels to boost the ORR performance. The FeSAs-NiCo alloy@N-C sphere exhibits exceptional mass activity and specific activity of 3.705 A.mg-1 and 8.79 mA.cm-2(ECSA), respectively, at 0.85 V versus RHE. It has a superior onset potential of 1.08 V versus RHE, surpassing that of its nanoparticle Fe counterpart and NiCo alloy@N-C sphere. The significant improvement in ORR performance of the FeSAs-NiCo alloy@N-C sphere could be attributed to the positive effects of increased lattice strain due to the single atoms of Fe-NX hybridized with small NiCo alloy NPs. The chitosan gel-assisted molten salt strategy and assistive active sites of Fe-NX hybridized with NiCo alloy NPs regulate the electronic properties of the FeSAs-NiCo alloy@N-C sphere, both geometrically via lattice strain mismatch and electronically through shifting of the d-band center. This could influence the binding energies for oxygen and/or oxygen reduction intermediate adsorption/desorption. The additional improvement in the ORR performance of the FeSAs-NiCo alloy@N-C sphere also benefits from having a lower electrochemical activation energy.

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