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1.
Front Immunol ; 13: 900080, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36059505

RESUMO

Developing a safe and effective malaria vaccine is critical to reducing the spread and resurgence of this deadly disease, especially in children. In recent years, vaccine technology has seen expanded development of subunit protein, peptide, and nucleic acid vaccines. This is due to their inherent safety, the ability to tailor their immune response, simple storage requirements, easier production, and lower expense compared to using attenuated and inactivated organism-based approaches. However, these new vaccine technologies generally have low efficacy. Subunit vaccines, due to their weak immunogenicity, often necessitate advanced delivery vectors and/or the use of adjuvants. A new area of vaccine development involves design of synthetic micro- and nano-particles and adjuvants that can stimulate immune cells directly through their physical and chemical properties. Further, the unique and complex life cycle of the Plasmodium organism, with multiple stages and varying epitopes/antigens presented by the parasite, is another challenge for malaria vaccine development. Targeting multistage antigens simultaneously is therefore critical for an effective malaria vaccine. Here, we rationally design a layer-by-layer (LbL) antigen delivery platform (we called LbL NP) specifically engineered for malaria vaccines. A biocompatible modified chitosan nanoparticle (trimethyl chitosan, TMC) was synthesized and utilized for LbL loading and release of multiple malaria antigens from pre-erythrocytic and erythrocytic stages. LbL NP served as antigen/protein delivery vehicles and were demonstrated to induce the highest Plasmodium falciparum Circumsporozoite Protein (PfCSP) specific T-cell responses in mice studies as compared to multiple controls. From immunogenicity studies, it was concluded that two doses of intramuscular injection with a longer interval (4 weeks) than traditional malaria vaccine candidate dosing would be the vaccination potential for LbL NP vaccine candidates. Furthermore, in PfCSP/Py parasite challenge studies we demonstrated protective efficacy using LbL NP. These LbL NP provided a significant adjuvant effect since they may induce innate immune response that led to a potent adaptive immunity to mediate non-specific anti-malarial effect. Most importantly, the delivery of CSP full-length protein stimulated long-lasting protective immune responses even after the booster immunization 4 weeks later in mice.


Assuntos
Quitosana , Vacinas Antimaláricas , Nanopartículas , Parasitos , Animais , Antígenos de Protozoários/metabolismo , Quitosana/metabolismo , Camundongos , Plasmodium falciparum
2.
Food Res Int ; 160: 111724, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36076415

RESUMO

Fruit softening is enzyme mediated degradation process determined by the action of cell wall modifying enzymes. Present study evaluated the combined effects of chitosan (CH) and salicylic acid (SA) coatings in modulation of fruit softening enzymes in Punjab Beauty pear (Pyrus pyrifolia × Pyrus communis) fruit stored under cold (0-1 °C and 90-95 % RH) and supermarket (20-22 °C and 80-85 % RH) conditions. Composite CH + SA coatings reduced mass loss and retained fruit firmness throughout the 67 and 20 days storage period. In addition, CH + SA prevented membrane damage by suppressing the electrolyte leakage and malondialdehyde (MDA) accumulation as compared to CH or SA alone. CH 2.0 % + SA 2.0 mM coating efficiently delayed the cell wall degrading enzymatic activities including pectin methylesterase (PME), polygalacturonase (PG) and cellulase associated with fruit softening up to 60 and 15 days storage period in cold and supermarket conditions, respectively.


Assuntos
Quitosana , Pyrus , Quitosana/metabolismo , Frutas/metabolismo , Pyrus/metabolismo , Ácido Salicílico , Supermercados
3.
Food Res Int ; 160: 111749, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36076471

RESUMO

Colon targeted delivery of quercetin by encapsulation has the potential to manage colonic diseases due to quercetin's pharmacological effects. To strengthen the functionalities of commonly used alginate microspheres for quercetin encapsulation, inulin was added as filling material and chitosan as coating material. Empty/quercetin-loaded alginate (AL-E/Q), alginate + inulin (ALIN-E/Q), alginate + inulin + chitosan (ALINCH-E/Q) microspheres were fabricated, with particle sizes ranging from 25.1 ± 1.8 to 79.4 ± 4.5 µm. All the formulated microspheres were negatively charged, and zeta potential was dependent mainly on chitosan coating and the pH of surrounding media. FTIR spectra of the microspheres suggested successful encapsulation of quercetin, formation of chitosan coating and potential hydrogen bonding between inulin and alginate. Scanning electron micrographs showed that inulin filling enhanced gel strength by filling up the pores in the alginate polymer network, and that loading of quercetin also helped to fill up the pores compared to empty microspheres. Combination of inulin as filling material and chitosan as coating material in quercetin loaded ALINCH-Q achieved superior performance compared to other formulations with encapsulation efficiency of 53.2 ± 1.2 %, and retention rate of the loaded quercetin up to 80.3 ± 4.4 % through in vitro gastrointestinal digestion, thus was chosen for colonic fermentation. Subjecting ALINCH-Q to colonic fermentation using pig fecal material as microbiota source showed that quercetin release was delayed but occurred within 3 h of fermentation and was completely metabolized by the microbiota by 24 h. Thus, ALINCH-Q microsphere showed potential in targeted delivery and release of quercetin to the colon.


Assuntos
Alginatos , Quitosana , Alginatos/metabolismo , Animais , Quitosana/metabolismo , Colo/metabolismo , Inulina/farmacologia , Microesferas , Quercetina/farmacologia , Suínos
4.
J Exp Clin Cancer Res ; 41(1): 281, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36131287

RESUMO

BACKGROUND: Circular RNA (circRNA), a new class of non-coding RNA, has obvious correlations with the occurrence and development of many diseases, including tumors. This study aimed to investigate the potential roles of circPAK1 in hepatocellular carcinoma (HCC). METHODS: High-throughput sequencing was performed on 3 pairs of HCC and matched normal tissues to determine the upregulated circRNAs. The expression level of circPAK1 was detected by qRT-PCR in HCC and paired with normal liver tissue samples. The effects of circPAK1 on proliferation, invasion, metastasis and apoptosis of HCC cells were evaluated by in vitro and in vivo experiments. We also constructed Chitosan/si-circPAK1 (CS/si-circPAK1) nanocomplexes using Chitosan material to evaluate its in vivo therapeutic effect on HCC. High-throughput sequencing, RNA-sequencing, RNA probe pull-down, RNA immunoprecipitation and Co-Immunoprecipitation assays were performed to explore the relationship between circPAK1, 14-3-3ζ, p-LATS1 and YAP. Exosomes isolated from lenvatinib-resistant HCC cell lines were used to evaluate the relationship between exosomal circPAK1 and lenvatinib resistance. RESULTS: CircPAK1, a novel circRNA, is highly expressed in HCC tumor tissues and cell lines as well as correlated with poor outcomes in HCC patients. Functionally, circPAK1 knockdown inhibited HCC cell proliferation, migration, invasion and angiogenesis while circPAK1 overexpression promoted HCC progression. The tumor-promoting phenotypes of circPAK1 on HCC were also confirmed by animal experiments. Importantly, the application of CS/si-circPAK1 nanocomplexes showed a better therapeutic effect on tumor growth and metastasis. Mechanistically, circPAK1 enhanced HCC progression by inactivating the Hippo signaling pathway, and this kind of inactivation is based on its competitively binding of 14-3-3 ζ with YAP, which weakens the recruitment and cytoplasmic fixation of 14-3-3 ζ to YAP, thus promoting YAP nucleus localization. Additionally, circPAK1 could be transported by exosomes from lenvatinib-resistant cells to sensitive cells and induce lenvatinib resistance of receipt cells. CONCLUSION: CircPAK1 exerts its oncogenic function by competitively binding 14-3-3 ζ with YAP, thus promoting YAP nucleus localization, leading to the inactivation of a Hippo signaling pathway. Exosomal circPAK1 may drive resistance to lenvatinib, providing a potential therapeutic target for HCC patients.


Assuntos
Carcinoma Hepatocelular , Quitosana , Neoplasias Hepáticas , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Animais , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células , Quitosana/metabolismo , Quitosana/farmacologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , Compostos de Fenilureia , Proteínas Serina-Treonina Quinases , Quinolinas , RNA Circular/genética , RNA não Traduzido , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
5.
Chem Biol Interact ; 365: 110094, 2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-35961540

RESUMO

BACKGROUND: Developing epigenetic drugs for breast cancer (BC) remains a novel therapeutic approach. Cromolyn is a mast cell stabilizer emerging as an anticancer drug; its encapsulation in chitosan nanoparticles (CSNPs) improves its effect and bioavailability. However, its effect on DNA and RNA methylation machineries has not been previously tackled. METHODS: The possible anticancer effect of cromolyn CSNPs and its potential as an epigenetic drug was investigated in vitro using MCF-7 human BC cell line and in vivo using Ehrlich ascites carcinoma-xenograft model in mice symbolizing murine mammary adenocarcinoma. Mice were injected with a single dose of Ehrlich ascites carcinoma cells subcutaneously for the induction of tumor mass, and then randomized into three groups: control, cromolyn CSNPs (equivalent to 5 mg cromolyn/kg, i.p.) and plain CSNPs twice/week for 2 weeks. RESULTS: Cromolyn CSNPs showed prominent anticancer effect in MCF-7 cells by reducing the cell viability percent and enhancing DNA damage in the comet assay demonstrating its apoptotic actions. Mechanistically, cromolyn CSNPs influenced potential epigenetic processes through mitigating DNA methyltransferase 1 (DNMT1) expression, reversing the hypermethylation pattern of the tumor suppressor RASSF1A and p16 genes and attenuating the expression of the RNA N6-methyladenosine writer, methyltransferase-like 3 (METTL3). Cromolyn CSNPs diminished ERK1/2 phosphorylation, a possible arm influencing DNMT1 expression. In vivo, cromolyn CSNPs lessened the tumor volume and halted DNMT1 and METTL3 expression in Ehrlich carcinoma mice. CONCLUSIONS: Cromolyn CSNPs have the premise as an epigenetic drug through inhibiting ERK1/2 phosphorylation/DNMT1/DNA methylation and possibly impacting the RNA methylation machinery via mitigating METTL3 expression.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Carcinoma/tratamento farmacológico , Quitosana/uso terapêutico , Cromolina Sódica/uso terapêutico , Metilação de DNA/efeitos dos fármacos , Nanopartículas , Animais , Ascite , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Carcinoma/genética , Carcinoma/metabolismo , Linhagem Celular Tumoral , Quitosana/metabolismo , Quitosana/farmacologia , Cromolina Sódica/metabolismo , Cromolina Sódica/farmacologia , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Modelos Animais de Doenças , Feminino , Regulação Neoplásica da Expressão Gênica , Genes p16 , Xenoenxertos , Humanos , Camundongos , RNA Neoplásico/metabolismo
6.
Fish Shellfish Immunol ; 128: 425-435, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35985625

RESUMO

Several studies have looked into the use of basil, Ocimum basilicum (L.) in aquaculture as a dietary additive; however, more research is needed to see the possibility of it's including in nanocarriers in aquafeeds. An experiment was undertaken to highlight the efficacy chitosan-Ocimum basilicum nanocomposite (COBN), for the first time, on Nile tilapia (Oreochromis niloticus) growth, stress and antioxidant status, immune-related parameters, and gene expression. For 60 days, fish (average weight: 23.55 ± 0.08 g) were fed diets provided with different concentrations of COBN (g/kg): 0 g [COBN0], 1 g [COBN1], 2 g [COBN2], and 3 g [COBN3], where COBN0 was kept as control diet. Following the trial, the fish were challenged with pathogenic bacteria (Aeromonas sobria) and yeast (Candida albicans) infection. In comparison to the control (COBN0), a notable increase in growth parameters (weight gain, feed intake, and specific growth rate) and intestinal morphometric indices (average intestinal goblet cells count, villous width, and length) in all COBN groups was observed, where COBN2 and COBN3 groups had the highest values. The COBN diets significantly (p < 0.05) declined levels of serum triglycerides, glucose, cholesterol, and hepatic malondialdehyde. Moreover, the higher levels of serum biochemical biomarkers (growth hormone, total protein, globulin, and albumin), immunological parameters (phagocytic activity%, nitric oxide, and lysozyme), and hepatic antioxidant parameters (superoxide dismutase, total antioxidant capacity, and glutathione peroxidase) were obvious in the COBN2 and COBN3 groups followed by COBN1. The immune-antioxidant genes (TNF-α, IL-10, IL-1ß, TGF-ß, GPx, and SOD) were found to be considerably up-regulated in all COBN groups (COBN2 and COBN3 followed by COBN1). Fifteen days post-challenge with A. sobria and C. albicans, the highest survival rate was recorded in the COBN2 group (83.33 and 91.67%) followed by the COBN3 group (75 and 83.33%), respectively. The findings showed that a dietary intervention with COBN can promote growth, intestinal architecture, immunity, and antioxidant markers as well as protect O. niloticus against A. sobria and C. albicans infection. As a result, the COBN at a dose of 2 g/kg could be used as a food additive for the sustainable aquaculture industry.


Assuntos
Quitosana , Ciclídeos , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Nanocompostos , Ocimum basilicum , Albuminas/metabolismo , Ração Animal/análise , Animais , Antioxidantes/metabolismo , Quitosana/metabolismo , Dieta/veterinária , Suplementos Nutricionais , Aditivos Alimentares , Expressão Gênica , Glucose/metabolismo , Glutationa Peroxidase/metabolismo , Hormônio do Crescimento , Rim Cefálico/metabolismo , Interleucina-10/metabolismo , Malondialdeído/metabolismo , Muramidase/metabolismo , Óxido Nítrico/metabolismo , Ocimum basilicum/metabolismo , Superóxido Dismutase/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Triglicerídeos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
7.
Int J Pharm ; 625: 122138, 2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-36029990

RESUMO

D-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS)-modified carboxymethyl chitosan-rhein (TCR) polymeric micelles (PMs) self-assembled by TCR conjugate were constructed for oral delivery of paclitaxel (PTX). PTX-loaded TCR PMs with a drug loading capacity of 47.52 ± 1.65 % significantly improved the intestinal absorption and oral bioavailability of PTX. TCR PMs loaded with PTX displayed time- and concentration-dependent cytotoxicity in Caco-2, MCF-7 and Taxol-resistant MCF-7 (MCF-7/Taxol) cells. In MCF-7/Taxol cells, PTX-loaded TCR PMs promoted apoptosis and changed cell cycle, and TCR conjugate exhibited a P-gp inhibition ability and caused ATP depletion. Moreover, confocal imaging of intestinal sections, Caco-2 cell uptake assay and in vivo bioimaging using environmental response fluorescence probe suggested that TCR PMs loaded with drugs can be absorbed as a whole through the intestinal epithelium after oral administration, enter systemic circulation, and then get to the tumor site. Remarkably, PTX-loaded TCR PMs displayed a significant antitumor effect in H22 tumor xenograft mice and the MCF-7 or MCF-7/Taxol xenograft zebrafish model, which was related to the inhibitory function of TCR conjugate for P-gp activity and P-gp and MDR1 expression. Functionalized TCR PMs are expected to improve the oral therapeutic efficacy of poorly water-soluble antitumor drugs and treat drug-resistant tumors.


Assuntos
Antineoplásicos Fitogênicos , Quitosana , Animais , Células CACO-2 , Linhagem Celular Tumoral , Quitosana/metabolismo , Portadores de Fármacos , Humanos , Camundongos , Micelas , Paclitaxel , Polímeros , Receptores de Antígenos de Linfócitos T , Peixe-Zebra/metabolismo
8.
Biomater Sci ; 10(18): 5243-5253, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-35912636

RESUMO

Nanoparticles administered into the maternal circulation and across the placenta are a potential clinical therapy to treat congenital diseases. The mechanism by which nanoparticles can safely cross the placenta for targeted drug delivery to the fetus remains poorly understood. We demonstrate that the maternal-fetal transfer of passive immunity through the neonatal Fc Receptor (FcRn) can induce the transplacental transfer of chitosan nanoparticles modifed with IgG antibodies (414 ± 27 nm). The transfer of FITC-tagged IgG-modified chitosan nanoparticles was 2.8 times higher (p = 0.0264) compared to similarly-sized unmodified chitosan nanoparticles (375 ± 17 nm). Co-administration of free IgG competitively diminished the transplacental transfer of IgG-modified nanoparticles, yet unmodified nanoparticles remained unaffected. Colocalization of the FcRn and the IgG-modified chitosan nanoparticles were observed with confocal microscopy. Barrier function before and after nanoparticle administration remained intact as determined by TEER (75-79 Ω cm2) and immmunofluorescence of ZO-1 tight junction proteins. The results provide insight into the clinical applications of nanoparticles for prenatal therapies using the mechanism of the maternal-fetal transfer of passive immunity.


Assuntos
Quitosana , Nanopartículas , Quitosana/metabolismo , Feminino , Feto , Humanos , Imunoglobulina G , Recém-Nascido , Placenta , Gravidez
9.
Carbohydr Polym ; 295: 119878, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35989018

RESUMO

At present, the tumor's poor oxygen perfusion and limited tumor drug permeation are the major bottlenecks that limit the therapeutic effectiveness of the oxygen-sensitive antitumor therapies, like doxorubicin (Dox)-mediated chemotherapy and photodynamic therapy (PDT). To our best knowledge, the abnormal tumor mitochondria oxidative phosphorylation (OXPHOS) was the vital cause of such phenomenon, which induced the hypoxia tumor microenvironment and enhanced drug efflux from tumor cells via enhanced multidrug resistance protein 1 (MDR-1) expression. In this study, it was newly revealed that biguanide-modified chitosan (Bi-Ch) possessed ideal mitochondria depression capacity, leading to the following decreased dosage needed to disrupt mitochondrial function to reverse tumor hypoxia and depress MDR-1 expression. By doing this, Bi-Ch effectively enhanced Dox accumulation in tumor cells and amplified its cytotoxicity owing to the amplified ROS generation by Dox. Therefore, Bi-Ch could be used to improve the efficacy of oxygen-sensitive tumor therapies in vitro.


Assuntos
Quitosana , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Biguanidas/farmacologia , Biguanidas/uso terapêutico , Linhagem Celular Tumoral , Quitosana/metabolismo , Quitosana/farmacologia , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Mitocôndrias/metabolismo , Oxigênio
10.
Drug Deliv ; 29(1): 2498-2512, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35903814

RESUMO

Spinal cord injury (SCI) is a serious central nervous system disease, and secondary injury, including oxidative stress, the inflammatory response and accompanying neuronal apoptosis, will aggravate the condition. Due to the existence of the blood-spinal cord barrier (BSCB), the existing drugs for SCI treatment are difficulty to reach the injury site and thus their efficacy is limited. In this study, we designed chitosan-modified hollow manganese dioxide nanoparticles (CM) for the delivery of resveratrol to help it pass through the BSCB. Resveratrol (Res), a poorly soluble drug, was adsorbed into CM with a particle size of approximately 130 nm via the adsorption method, and the drug loading reached 21.39 ± 2.53%. In vitro dissolution experiment, the Res release of the loaded sample (CMR) showed slowly release behavior and reached about 87% at 36 h. In vitro at the cellular level and in vivo at the animal level experiments demonstrated that CMR could alleviate significantly oxidative stress by reducing level of reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), and increasing glutathione peroxidase (GSH) level. Additionally, immunofluorescence (iNOS, IL-1ß, and Cl caspase-3) and western blot (iNOS, cox-2, IL-1ß, IL-10, Cl caspase-3, bax, and bcl-2) were used to detect the expression of related factors, which verified that CMR could also reduce inflammation and neuronal apoptosis. These results indicated that CM, as a potential central nervous system drug delivery material, was suitable for SCI treatment.


Assuntos
Quitosana , Nanopartículas , Traumatismos da Medula Espinal , Animais , Apoptose/fisiologia , Caspase 3/metabolismo , Quitosana/metabolismo , Compostos de Manganês , Estresse Oxidativo , Óxidos , Ratos , Ratos Sprague-Dawley , Resveratrol/farmacologia , Resveratrol/uso terapêutico , Traumatismos da Medula Espinal/tratamento farmacológico
11.
Int J Mol Sci ; 23(13)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35806282

RESUMO

Inspired by the composition and confined environment provided by collagen fibrils during bone formation, this study aimed to compare two different strategies to synthesize bioactive hybrid membranes and to assess the role the organic matrix plays as physical confinement during mineral phase deposition. The hybrid membranes were prepared by (1) incorporating calcium phosphate in a biopolymeric membrane for in situ hydroxyapatite (HAp) precipitation in the interstices of the biopolymeric membrane as a confined environment (Methodology 1) or (2) adding synthetic HAp nanoparticles (SHAp) to the freshly prepared biopolymeric membrane (Methodology 2). The biopolymeric membranes were based on hydrolyzed collagen (HC) and chitosan (Cht) or κ-carrageenan (κ-carr). The hybrid membranes presented homogeneous and continuous dispersion of the mineral particles embedded in the biopolymeric membrane interstices and enhanced mechanical properties. The importance of the confined spaces in biomineralization was confirmed by controlled biomimetic HAp precipitation via Methodology 1. HAp precipitation after immersion in simulated body fluid attested that the hybrid membranes were bioactive. Hybrid membranes containing Cht were not toxic to the osteoblasts. Hybrid membranes added with silver nanoparticles (AgNPs) displayed antibacterial action against different clinically important pathogenic microorganisms. Overall, these results open simple and promising pathways to develop a new generation of bioactive hybrid membranes with controllable degradation rates and antimicrobial properties.


Assuntos
Quitosana , Nanopartículas Metálicas , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Quitosana/metabolismo , Quitosana/farmacologia , Colágeno/metabolismo , Durapatita/metabolismo , Osteoblastos/metabolismo , Prata/metabolismo , Prata/farmacologia
12.
Fish Shellfish Immunol ; 127: 715-729, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35835382

RESUMO

The potential synbiotic effects of a Bacillus mixture and chitosan on growth, immune responses and disease resistance against Vibrio parahaemolyticus, the causative agent of acute hepatopancreatic necrosis disease (AHPND) in Pacific white shrimp, were intensively investigated. Three effective strains of Bacillus amyloliquefaciens (A), Bacillus pumilus (P) and Bacillus subtilis (S) were mixed in pairs at a ratio of 5 × 108:5 × 108 CFU/kg diet and coated with the prebiotic chitosan (C) at a concentration of 20 mL/kg diet. Five different feed treatments were used to feed experimental shrimp for 5 weeks: control (control, no synbiotics), chitosan (coat, C) and the synbiotic treatments PAC, PSC and ASC. At week 5, the final length, final weight gain, weight gain, length, average daily gain, specific growth rate and feed conversion ratio, measured as growth parameters, were significantly upregulated in the PSC and ASC groups compared with the control and coat groups (P < 0.05). This result was consistent with the expression analysis of two growth-related genes (Rap-2a and GF-II) in the hepatopancreas and intestines of treated shrimp, as determined using qRT-PCR. The prebiotic chitosan and synbiotics PAC, PSC and ASC strongly induced significant differences in the expression of the Rap-2a and GF-II genes in the target organs compared with the expression in the control group at various time points (P < 0.05). Additionally, application of the synbiotic treatments also significantly enhanced the hepatopancreas characteristics and epithelial and intestinal wall thicknesses of the shrimp compared with the control. Interestingly, all the synbiotic treatments elevated phagocytic activity significantly at weeks 3 and 5 compared with that in the other groups. qRT-PCR analysis of immune-related genes also indicated that the prebiotic group and all synbiotic groups showed strong expression of anti-lipopolysaccharide (ALF) and prophenoloxidase (proPO) genes in the intestine. Finally, the synbiotic groups PAC, PSC and ASC exhibited stronger VPAHPND resistance at 120 h after exposure than the chitosan coat and control groups, with survival rates of 41.7 ± 11.55, 41.7 ± 0.00, 52.8 ± 5.77, 30.6 ± 15.28 and 22.2 ± 5.77%, respectively (P < 0.05). Based on the obtained information, all synbiotics were recommended for improved growth and immune responses, while ASC was the best for disease resistance against VPAHPND in Pacific white shrimp.


Assuntos
Bacillus , Quitosana , Penaeidae , Vibrio parahaemolyticus , Animais , Proteínas de Artrópodes/genética , Quitosana/metabolismo , Quitosana/farmacologia , Resistência à Doença , Imunidade Inata , Necrose , Vibrio parahaemolyticus/fisiologia
13.
Planta ; 256(2): 32, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35794498

RESUMO

MAIN CONCLUSION: Peanut cultivars are known to produce stilbene compounds. Transcriptional control plays a key role in the early stages of the stress response mechanism, involving both PR-proteins and stilbene compounds. In this study, the production of stilbenoid compounds, especially prenylated, was investigated in two cultivars of peanut hairy root lines, designated as K2-K599 and T9-K599 elicited with a combination of chitosan (CHT), methyl jasmonate (MeJA), and cyclodextrin (CD): CHT + MeJA + CD. The antioxidant activities and stilbenoid content of both K2-K599 and T9-K599 hairy root lines increased significantly during the elicitation period. The T9-K599 hairy root line expressed higher ABTS and FRAP antioxidant activities than the K2-K599 line while the latter exhibited greater total phenolic content than the former at all-time points. Additionally, the K2-K599 line exhibited more stilbene compounds, including trans-resveratrol, trans-arachidin-1, and trans-arachidin-3 than the T9-K599 line, which showed statistically significant differences at all-time points. Gene expression of the enzyme involved in the stilbene biosynthesis pathway (PAL, RS, RS3) was observed, responding early to elicitor treatment and the metabolic production of a high level of stilbenoid compounds at a later stage. The antioxidant enzyme (CuZn-SOD, APX, GPX) and pathogenesis-related protein (PR; PR4A, PR5, PR10, chitinase) genes were strongly expressed after elicitor treatment at 24 h and decreased with an increasing elicitation time. Investigation of the response mechanism illustrates that the elicitor treatment can affect various plant responses, including plant cell wall structure and integrity, antioxidant system, PR-proteins, and secondary plant metabolites at different time points after facing external environmental stimuli.


Assuntos
Quitosana , Ciclodextrinas , Fabaceae , Estilbenos , Acetatos , Antioxidantes/metabolismo , Arachis/genética , Quitosana/análise , Quitosana/metabolismo , Ciclodextrinas/análise , Ciclodextrinas/metabolismo , Ciclopentanos , Fabaceae/metabolismo , Oxilipinas , Raízes de Plantas/metabolismo , Estilbenos/metabolismo
14.
Int J Biol Macromol ; 217: 188-192, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-35839947

RESUMO

This study investigated the effects of feeding different concentrations of chitosan on the growth performance, body composition and non-specific immune function of juvenile yellow catfish (Pelteobagrus fulvidraco). Four kinds of experimental diets were respectively prepared by adding 0 (control group), 5, 10 and 15 g/kg of chitosan to the basal feed and fed to juvenile yellow catfish for 8 weeks. Results show that the body weight gain rate, specific growth rate, survival rate, body protein content, serum superoxide dismutase activity, catalase activity, glutathione peroxidise activity, lysozyme activity and disease resistance ability against Aeromonas hydrophila of the experimental group with chitosan added to its diet were significantly higher than those of the control group optimally by 36.22 %, 14.37 %, 9.46 %, 8.97 %, 50.89 %, 33.15 %, 21.52 %, 40.80 %, 41.09 %, and 79.71 %, respectively (P < 0.05). No significant differences in feed efficiency among all groups (P > 0.05) were observed. The optimum dose of dietary chitosan required for the maximum growth of juvenile yellow catfish was 8.95 g/kg. Therefore, adding an appropriate amount of chitosan (8.95 g/kg) to the feed of yellow catfish can significantly improve its growth performance, ameliorate body composition and enhance its non-specific immunity.


Assuntos
Peixes-Gato , Quitosana , Doenças dos Peixes , Ração Animal/análise , Animais , Composição Corporal , Peixes-Gato/metabolismo , Quitosana/metabolismo , Quitosana/farmacologia , Dieta , Suplementos Nutricionais , Resistência à Doença , Imunidade Inata
15.
Int J Biol Macromol ; 217: 522-535, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-35841966

RESUMO

This study describes the fabrication of cellulose scaffold (CS) and cellulose-chitosan (CS/CHI) scaffolds from the immature endosperm of Borassus flabellifer (Linn.) (BF) loaded with platelet rich plasma (PRP). Thus, developed scaffolds were evaluated for their physicochemical and mechanical behavior, growth factor release and biological performance. Additionally, in vivo response was assessed in a sub cutaneous rat model to study vascularization, host inflammatory response and macrophage polarization. The results of this study demonstrated that CS and CS/CHI scaffolds with PRP demonstrated favorable physiochemical and morphogical properties. The scaffold groups CS-PRP and CS/CHI-PRP were able to release growth factors in a well sustained manner under physiological conditions. The presence of PRP in cellulosic scaffolds did show significant differences in their behavior when investigated under in vitro studies, where the release of diverse cytokines improved the cellular proliferation and differentiation of osteoblasts. Finally, the PRP enriched scaffolds when studied under in vivo conditions showed increased angiogenesis and re-epithelialization with adequate collagen deposition and tissue remodeling. Our results suggest that besides the conventional carrier systems, this new-generation of plant-based cellulosic scaffolds with/without any modification can serve as a suitable carrier for PRP encapsulation and release, which can be used in numerous tissue regenerative therapies.


Assuntos
Quitosana , Plasma Rico em Plaquetas , Animais , Celulose/metabolismo , Celulose/farmacologia , Quitosana/metabolismo , Quitosana/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Plasma Rico em Plaquetas/metabolismo , Ratos , Engenharia Tecidual/métodos , Tecidos Suporte/química
16.
PLoS Pathog ; 18(6): e1010195, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35737716

RESUMO

Copper homeostasis mechanisms are essential for microbial adaption to changing copper levels within the host during infection. In the opportunistic fungal pathogen Cryptococcus neoformans (Cn), the Cn Cbi1/Bim1 protein is a newly identified copper binding and release protein that is highly induced during copper limitation. Recent studies demonstrated that Cbi1 functions in copper uptake through the Ctr1 copper transporter during copper limitation. However, the mechanism of Cbi1 action is unknown. The fungal cell wall is a dynamic structure primarily composed of carbohydrate polymers, such as chitin and chitosan, polymers known to strongly bind copper ions. We demonstrated that Cbi1 depletion affects cell wall integrity and architecture, connecting copper homeostasis with adaptive changes within the fungal cell wall. The cbi1Δ mutant strain possesses an aberrant cell wall gene transcriptional signature as well as defects in chitin / chitosan deposition and exposure. Furthermore, using Cn strains defective in chitosan biosynthesis, we demonstrated that cell wall chitosan modulates the ability of the fungal cell to withstand copper stress. Given the previously described role for Cbi1 in copper uptake, we propose that this copper-binding protein could be involved in shuttling copper from the cell wall to the copper transporter Ctr1 for regulated microbial copper uptake.


Assuntos
Quitosana , Criptococose , Cryptococcus neoformans , Parede Celular/metabolismo , Quitina/metabolismo , Quitosana/metabolismo , Cobre/metabolismo , Proteínas de Transporte de Cobre , Criptococose/microbiologia , Cryptococcus neoformans/genética , Cryptococcus neoformans/metabolismo , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Homeostase
17.
Carbohydr Polym ; 291: 119571, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35698392

RESUMO

A porous starch-based carrier coated with chitosan-phytic acid was designed for oral administration to improve drug delivery to the colon. Using hydrophobic paclitaxel as a model drug, improved drug loading (15.12% ±â€¯0.31%) and entrapment efficiency (86.63 ±â€¯1.30%) of porous starch were achieved by size/shape matching and adsorption force. Fluorescent paclitaxel particles inside starch were captured clearly. Furthermore, chitosan-phytic acid was added as a second protection since porous starch showed a dissolution rate of only 14.98-20.27% during the simulated digestion in stomach and small intestine, which was far lower than that of raw paclitaxel in porous starch (59.65 ±â€¯2.57%). The release curve in the colon was also obtained and showed that 86.98 ±â€¯2.90% of the drug was released. Finally, we verified the non-covalent interactions between starch and paclitaxel. This showed that the retention of paclitaxel into porous starch decreased once hydrogen bonding stopped. The hydrophobic CH-π effect provides a binding complementing contribution.


Assuntos
Quitosana , Amido , Adsorção , Quitosana/metabolismo , Colo/metabolismo , Preparações de Ação Retardada/metabolismo , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Excipientes/metabolismo , Microesferas , Paclitaxel/química , Ácido Fítico , Porosidade , Amido/química
18.
Int J Biol Macromol ; 214: 632-641, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35760163

RESUMO

Productivity enhancement approaches, such as elicitation can overcome the limitations of low metabolite(s) yield in in vitro plant cell culture platforms. Application of biotic/abiotic elicitors triggers molecular responses that lead to a concomitant enhancement in the production of metabolites. Nanoparticles have been tested as alternatives to commonly studied biotic/abiotic elicitors. However, most nanoparticles explored are of metallic origin, which raises concerns about their cytotoxicity, disposal post-elicitation, and may limit downstream applications of metabolites. Here, we report the synthesis and application of biopolymeric methyl jasmonate-loaded chitosan nanoparticles (MJ-CNPs) and empty CNPs (size <100 nm) as nano-elicitors, which were simple to synthesize, cost-effective and safe. Enzymatic and metabolic investigations revealed that MJ-CNPs and empty CNPs improve and prolong phenylalanine ammonia-lyase enzyme activity and production of phenolics and flavonoids. The data provides the first evidence of MJ-CNPs and empty CNPs as nano-elicitors that prolong the production of metabolites in plant cell suspension cultures.


Assuntos
Quitosana , Nanopartículas , Acetatos , Quitosana/metabolismo , Ciclopentanos , Flavonoides/metabolismo , Oxilipinas , Fenóis/metabolismo , Células Vegetais
19.
J Agric Food Chem ; 70(24): 7479-7489, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35678723

RESUMO

Cell surface display technology, which expresses and anchors proteins on the surface of microbial cells, has broad application prospects in many fields, such as protein library screening, biocatalysis, and biosensor development. However, traditional cell surface display systems have disadvantages: the molecular weight of phage display proteins cannot be too large; bacterial display lacks the post-translational modification process for eukaryotic proteins; yeast display is prone to excessive protein glycosylation and misfolding of multisubunit proteins; and the compatibility of Bacillus subtilis spore display needs to be further improved. Therefore, it is extremely valuable to develop an efficient surface display platform with strong universality and stress resistance properties. Although yeast surface display systems have been extensively investigated, the establishment of a surface display platform using yeast spores has rarely been reported. In this study, a novel cell surface display platform based on natural "chitosan beads" of yeast spores was developed. The target protein in fusion with the chitosan affinity protein (CAP) exhibited strong binding capability with "chitosan beads" of yeast spores in vitro and in vivo. Moreover, this protein display system showed highly preferable enzymatic properties and stability. As an example, the displayed LXYL-P1-2-CAP demonstrated high thermostability and reusability (60% of the initial activity after seven cycles of reuse), high storage stability (75% of original activity after 8 weeks), and excellent tolerance to a concentration up to 75% (v/v) organic reagents. To prove the practicability of this surface display system, the semisynthesis of paclitaxel intermediate was demonstrated and its highest conversion rate was 92% using 0.25 mM substrate. This study provides a novel and useful platform for the surface display of proteins, especially for multimeric macromolecular proteins of eukaryotic origin.


Assuntos
Quitosana , Esporos Bacterianos , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , Quitosana/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Esporos Bacterianos/genética , Esporos Bacterianos/metabolismo , Esporos Fúngicos/metabolismo
20.
Carbohydr Polym ; 290: 119499, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35550777

RESUMO

As an important transcription factor, c-Jun could upregulate growth factors expression in Schwann cells (SCs). Arginine-Glycine-Aspartate (RGD)-functionalized chitosan-graft-polyethyleneimine (RCP) gene vectors were prepared through the maleic anhydride & the carbodiimide methods, and electrostatically bound with c-Jun plasmids (pJUN), finally loaded on poly-L-lactic acid/silk fibroin parallel fiber films to fabricate nerve scaffold (RCP/pJUN-PSPF@PGA), which could locally deliver c-Jun plasmids into SCs via the mediation of RGD peptides, and upregulate the expression of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) in SCs. After the scaffold was bridged in sciatic nerve defect, the delivery of c-Jun plasmids from RCP/pJUN-PSPF@PGA facilitated SCs to sustain the expressions of NGF, BDNF and vascular endothelial growth factor in the injury field, promoting myelination, axonal growth and microvascular generation and nerve regeneration, muscle reinnervation and functional recovery. These results suggested that RCP/pDNA-PSPF@PGA, as an effective gene delivery platform, could provide a local gene therapy to improve nerve regeneration.


Assuntos
Quitosana , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Quitosana/metabolismo , Terapia Genética , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/metabolismo , Regeneração Nervosa , Oligopeptídeos , Polietilenoimina/metabolismo , Prostaglandinas A/metabolismo , Células de Schwann , Nervo Isquiático/lesões , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
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