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1.
Biopolymers ; 115(5): e23604, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38818788

RESUMO

Schizophyllan is a triple helical ß-1,3-D-glucan, and shows the cooperative order-disorder transition in the aqueous solution at the triple helix state. In this paper, the solvent stabilizing effects of two carboxylic acids, acetic acid and citric acid, on the cooperative order-disorder transition of aqueous schizophyllan solution were investigated from DSC and SEC-MALS measurements. The transition temperature (Tr) was shifted to higher temperature with increasing the molar fraction of carboxylic acid in the mixture (x). The transition enthalpy (ΔHr) was increased with increasing x. These solvent stabilizing effects indicate that these carboxylic acid molecules were selectively associated with the branched side chains of schizophyllan to stabilize the ordered state. The composition dependencies of Tr and ΔHr were analyzed by the linear cooperative transition theory to estimate the association parameters between the side chains and carboxylic acid. The theoretical parameters obtained were compared with those for the other active substances for the transition to discuss the molecular interactions between the triple helix and carboxylic acid.


Assuntos
Ácidos Carboxílicos , Sizofirano , Solventes , Termodinâmica , Água , Solventes/química , Água/química , Ácidos Carboxílicos/química , Sizofirano/química , Ácido Cítrico/química , Temperatura de Transição , Varredura Diferencial de Calorimetria , Ácido Acético/química
2.
Langmuir ; 38(5): 1748-1756, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35089712

RESUMO

Schizophyllan, a triple helical polysaccharide, exhibits cooperative order-disorder transition (CODT) in aqueous solutions. The transition transforms the ordered structure (triple helix I) formed between the branched side chains and solvent molecules into the disordered structure (triple helix II) without dissociation of the triple helix. The CODT behaviors in H2O-imidazole mixtures containing HCl with different molar ratios of imidazole/HCl were investigated by adiabatic calorimetry and differential scanning calorimetry on two schizophyllan solutions with different molar masses. The transition temperature (Tr) and the transition enthalpy (ΔHr) significantly depended on both of the mole fractions of imidazole and imidazole/HCl. The composition dependences of Tr and ΔHr in H2O-imidazole mixtures were analyzed with linear cooperative transition theory for the solvent-stabilizing effect in the mixture with active compounds. Theoretical analyses confirmed that both imidazole and imidazolium ions in the solutions competitively interact with the side chain of the triple helix.


Assuntos
Sizofirano , Varredura Diferencial de Calorimetria , Configuração de Carboidratos , Imidazóis , Sizofirano/química , Soluções , Água/química
3.
Int J Mol Sci ; 22(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202080

RESUMO

Alveolar macrophages are the first line of defense against intruding pathogens and play a critical role in cancer immunology. The Toll-like receptor (TLR) family mediates an important role in recognizing and mounting an immune response against intruding microbes. TLR-9 is a member of the intracellular TLR family, which recognizes unmethylated CG motifs from the prokaryotic genome. Upon its activation, TLR-9 triggers downstream of the MyD-88-dependent transcriptional activation of NF-κB, and subsequently results in abundant inflammatory cytokines expression that induces a profound inflammatory milieu. The present exploratory investigation aimed at elucidating the potency of schizophyllan for entrapping ODN 1826 (SPG-ODN 1826)-mediated stimulation of TLR-9 in provoking an inflammatory-type response in murine alveolar macrophages. Schizophyllan (SPG), a representative of the ß-glucan family, was used in the present study as a nanovehicle for endosomal trafficking of CpG ODN 1826. TEM analysis of SPG-ODN 1826 nanovehicles revealed that the prepared nanovehicles are spherical and have an average size of about 100 nm. Interestingly, SPG-ODN 1826 nanovehicles were competent in delivering their therapeutic payload within endosomes of murine alveolar macrophage (J774A.1) cells. Exposure of these nanovehicles within LPS stimulated J774A.1, resulted in a significant provocation of reactive oxygen species (ROS) (p < 0.01) in comparison to CpG ODN 1826 alone. Moreover, the formulated nanovehicles succeeded in generating a profound Th1-based cytokine profile constituted by enhanced expression of IFN-γ (p < 0.001) and IL-1ß (p < 0.001) inflammatory cytokines. These findings clearly indicated the immunostimulatory potential of SPG-ODN 1826 nanovehicles for inducing the Th1-type phenotype, which would certainly assist in skewing M2 phenotype into the much-desired M1 type during lung cancer.


Assuntos
Macrófagos Alveolares/imunologia , Macrófagos Alveolares/metabolismo , Nanoestruturas/química , Oligodesoxirribonucleotídeos/química , Sizofirano/química , Receptor Toll-Like 9/agonistas , Animais , Sobrevivência Celular , Citocinas/metabolismo , Endossomos , Imunofenotipagem , Mediadores da Inflamação/metabolismo , Ativação de Macrófagos/imunologia , Camundongos , Nanoestruturas/administração & dosagem , Nanoestruturas/ultraestrutura , Tamanho da Partícula
4.
Bioorg Med Chem ; 28(18): 115668, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32828430

RESUMO

Antisense oligonucleotides (AS-ODNs) specifically hybridize with target mRNAs, resulting in interference with the splicing mechanism or the regulation of protein translation. In our previous reports, we demonstrated that ß-glucan schizophyllan (SPG) can form a complex with AS-ODNs attached with oligo deoxyadenosine dA40 (AS-ODN-dA40/SPG), and that this complex can be recognized by ß-glucan receptor Dectin-1 on antigen presenting cells and lung cancer cells. In many types of cancer cell, activating K-ras mutations related to malignancy are frequently observed. In this study, we first designed 78 AS-ODNs for K-ras to optimize the sequence for highly efficient gene suppression. The selected AS-ODN (K-AS07) having dA40 made a complex with SPG. The resultant complex (K-AS07-dA40/SPG) showed an effect of silencing the ras gene in the cells (PC9: human adenocarcinoma differentiated from lung tissue) expressing Dectin-1, leading to the suppression of cell growth. Furthermore, the cytotoxic effect was enhanced when used in combination with the anticancer drug gemcitabine. Gemcitabine, a derivative of cytidine, was shown to interact with dA40 in a sequence-dependent manner. This interaction did not appear to be so strong, with the gemcitabine being released from the complex after internalization into the cells. SPG and the dA40 part of K-AS07-dA40 play roles in carriers for K-AS07 and gemcitabine, respectively, resulting in a strong cytotoxic effect. This combination effect is a novel feature of the AS-ODN-dA40/SPG complexes. These results could facilitate the clinical application of these complexes for cancer treatment.


Assuntos
Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Oligonucleotídeos Antissenso/química , Sizofirano/química , Sequência de Aminoácidos , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Células Cultivadas , Desoxicitidina/química , Desoxicitidina/farmacologia , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Quimioterapia Combinada , Humanos , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Oligonucleotídeos Antissenso/farmacologia , Sizofirano/farmacologia , Gencitabina
5.
Biopolymers ; 110(9): e23315, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31180595

RESUMO

ß-1,3-d-glucan with different degrees of branching were obtained by selectively and gradually removing side chains from schizophyllan, a water-soluble triple helical polysaccharide, using the Smith degradation. Size exclusion chromatography combined with a multi-angle light scattering detection was performed in aqueous 0.1 M NaCl. The degree of branching decreased after the Smith degradation, while the molar mass distributions were almost unchanged. The molecular conformation of the Smith-degraded ß-1,3-d-glucan was analyzed on the basis of the molar mass dependency of the radius gyration, and found to be comparable to the original triple helix of schizophyllan. Differential scanning calorimetry in deuterium oxide-hexadeuterodimethylsulfoxide mixtures was performed to investigate the effects of the degree of branching on the cooperative order-disorder transition. Removal of side chains affects both the transition temperature and transition enthalpy. The ordered structure is formed by the residual side chains in the triplex unit, so that the linear cooperative system of the triplex is maintained after the Smith degradation.


Assuntos
Sizofirano/química , beta-Glucanas/química , Varredura Diferencial de Calorimetria , Configuração de Carboidratos , Cromatografia em Gel , Difusão Dinâmica da Luz , Glucana 1,3-beta-Glucosidase/química , Glucana 1,3-beta-Glucosidase/metabolismo , Peso Molecular , Proteoglicanas , Cloreto de Sódio , Soluções/química , Termodinâmica , Água/química
6.
Bioconjug Chem ; 28(9): 2246-2253, 2017 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-28738674

RESUMO

The efficient induction of antigen-specific immune responses requires not only promotion of the uptake of antigens and adjuvant molecules into antigen-presenting cells but also control of their intracellular behavior. We previously demonstrated that the ß-glucan schizophyllan (SPG) can form complexes with CpG oligonucleotides with attached dA40 (CpG-dA/SPG), which can accumulate in macrophages in the draining inguinal lymph nodes and induce strong immune responses. In this study, we prepared various conjugates composed of antigenic peptide (OVA257-264) and dA40 and made complexes with SPG. The conjugates with a disulfide bond between OVA257-264 and dA40 were easily cleaved by glutathione. The resultant peptides with a hydrophobic amino acid at the C-terminal end was recognized by puromycin-insensitive leucine aminopeptidase (PILS-AP), which trims antigenic peptide precursors and prepares peptides of eight or nine amino acids in length, which is the optimal length for binding to major histocompatibility complex (MHC)-I. The conjugate exposed to such enzymes induced a high antigen presentation level. The antigen presentation level was almost the same before and after the complexation with SPG. Immunization with a mixture of dA-OVA257-264/SPG and CpG-dA/SPG induced high antigen-specific cytotoxic T-lymphocyte activity at a much lower peptide dose than in previous studies. These results can be strongly ascribed to not only the cell-specific delivery by SPG but also the control of the intracellular behavior by the introduction of cleavage sites. Therefore, peptide-dA/SPG complexes could be used as potent vaccine antigens for the treatment of cancers and infectious diseases.


Assuntos
Aminopeptidases/metabolismo , Glutationa/metabolismo , Oligodesoxirribonucleotídeos/imunologia , Ovalbumina/imunologia , Sizofirano/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Controle de Doenças Transmissíveis , Doenças Transmissíveis/imunologia , Doenças Transmissíveis/metabolismo , Imunização , Macrófagos/imunologia , Camundongos , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/prevenção & controle , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/metabolismo , Ovalbumina/química , Ovalbumina/metabolismo , Sizofirano/química , Sizofirano/metabolismo , Linfócitos T Citotóxicos/metabolismo
7.
Prep Biochem Biotechnol ; 46(3): 313-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25830418

RESUMO

Schizophyllan is a biopolymer commercially produced for pharmaceutical and cosmetics uses. However, schizophyllan also has potential biomaterial applications. Schizophyllan is conventionally produced from glucose and recovered by diafiltration and ultrafiltration to produce a highly purified product. Here we demonstrate a simplified process for preparation of schizophyllan solutions for biomaterial applications. Schizophyllan was produced in 1.5-L bioreactors from distiller's dried grains with solubles (DDGS), an abundant coproduct of dry grind fuel ethanol production. Downstream processing eliminated filtration and concentration steps, providing solutions containing 4.2 ± 0.3 g schizophyllan/L. Solutions contained high-molecular-weight schizophyllan and exhibited viscosity properties similar to those of commercial schizophyllan. Schizophyllan solutions showed promise as a component of biolubricants in friction and wear tests and by dynamic surface and interfacial tension measurements.


Assuntos
Materiais Biocompatíveis , Sizofirano/química , Reatores Biológicos
8.
Gene Ther ; 22(3): 217-26, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25567536

RESUMO

The CD40/CD154 co-stimulatory pathway is crucial in alloimmune response. We developed a novel small interfering RNA (siRNA) delivery system with a poly-dA extension at the 5'-end of the siRNA sense strand that was stably incorporated into 1,3-ß-glucan (schizophyllan, SPG). This was captured and incorporated into dendritic cells (DCs) through its receptor, Dectin-1, specifically silencing CD40 genes (siCD40) to exert immunoregulatory activity. siCD40/SPG-treated CBA mice permanently accepted B10 fully mismatched cardiac allografts. Consistent with graft survival, the infiltration of CD4(+), CD8(+) T cells into the graft was lower, and that the numbers of CD40(low)CD11c(+) DCs cells and CD4(+)Foxp3(+)cells were increased in both the graft and in the recipient spleen. In addition, naive CBA recipients given an adoptive transfer of splenocytes from the primary recipients with siCD40/SPG accepted a heart graft from donor-type B10, but not third-party Balb/c mice. In conclusion, the treatment with siCD40/SPG targeting DCs could generate antigen-specific Tregs, resulting in the permanent acceptance of mouse cardiac allografts. These findings have important implications for clarifying the mechanism underlying the induction of tolerance in DCs, and also highlight the potential of immunomodulation and the feasibility of siRNA-based clinical therapy in the transplantation field.


Assuntos
Adjuvantes Imunológicos/metabolismo , Aloenxertos/fisiologia , Antígenos CD40/metabolismo , Transplante de Coração , Células Mieloides/metabolismo , RNA Interferente Pequeno/metabolismo , Sizofirano/metabolismo , Adjuvantes Imunológicos/química , Aloenxertos/citologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Cultivadas , Células Dendríticas/imunologia , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética , Sizofirano/química , Subpopulações de Linfócitos T/imunologia , Transfecção
9.
Carbohydr Polym ; 339: 122252, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823919

RESUMO

Drug delivery technologies that could convert promising therapeutics into successful therapies have been under broad research for many years. Recently, ß-glucans, natural-occurring polysaccharides extracted from many organism species such as yeast, fungi and bacteria, have attracted increasing attention to serve as drug delivery carriers. With their unique structure and innate immunocompetence, ß-glucans are considered as promising carriers for targeting delivery especially when applied in the vaccine construction and oral administration of therapeutic agents. In this review, we focus on three types of ß-glucans applied in the drug delivery system including yeast ß-glucan, Schizophyllan and curdlan, highlighting the benefits of ß-glucan based delivery system. We summarize how ß-glucans as delivery vehicles have aided various therapeutics ranging from macromolecules including proteins, peptides and nucleic acids to small molecular drugs to reach desired cells or organs in terms of loading strategies. We also outline the challenges and future directions for developing the next generation of ß-glucan based delivery systems.


Assuntos
Portadores de Fármacos , Sistemas de Liberação de Medicamentos , beta-Glucanas , Humanos , beta-Glucanas/química , Animais , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Sizofirano/química
10.
Int J Biol Macromol ; 259(Pt 1): 129108, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38158055

RESUMO

ß-D-glucan has significant implications in regulating lipid metabolism and preventing diseases associated with lipid accumulation. Schizophyllan (SPG) from Schizophyllum commune fungus is a commercially important ß-glucan with applications in the health food industry, pharmacy, and cosmetics. However, SPG was obtained by submerged culture of the wood-rotting and filamentous fungus S. commune BRM 060008, which may have been isolated from the Cerrado Biome of Brazil. In this study, to confirm that the polysaccharide produced by BRM 060008 strain fermentation was indeed (1→3)(1→6)-ß-D-glucan, it was purified and characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, high-performance size exclusion chromatography, nuclear magnetic resonance, and methylation analysis. The polysaccharide produced was identified as the ß-D-glucan expected with a high molecular weight (1.093 × 106 g/mol) and the thermogravimetric analysis indicated a maximum degradation temperature of ~324 °C and a 60 % residual weight, lower than commercial SPG. The molecular structure and thermal properties of the ß-D-glucan were similar to the commercial sample. Additionally, the in vitro pancreatic lipase inhibitory activity was evaluated, investigating anti-obesity and anti-lipidemic properties. The results showed unprecedented lipase inhibition activity to SPG prepared using the S. commune strain BRM 060008, making it promising for food and pharmaceutical applications.


Assuntos
Schizophyllum , Sizofirano , Sizofirano/farmacologia , Sizofirano/química , Schizophyllum/metabolismo , Glucanos/metabolismo , Lipase/metabolismo , Polissacarídeos/metabolismo
11.
Mol Ther ; 20(6): 1234-41, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22334022

RESUMO

Antisense technologies for the targeted inhibition of gene expression could provide an effective strategy for the suppression of inflammation. However, the effective use of antisense oligonucleotides (ODN) has been limited because of several problems. Therefore, a delivery system for antisense ODNs that enhances antisense stability, while maintaining the specificity of antisense for its target RNA or DNA is needed. We have developed a delivery system for antisense ODN using schizophyllan (SPG), a polysaccharide that belongs to the ß-(1-3) glucan family. This system has several advantages enabling the effective suppression of targeted RNA or DNA: the SPG complex is stable in vivo and does not dissolve in the presence of deoxyribonuclease, and the SPG complex is effectively taken up into macrophages by phagocytosis through Dectin-1. Macrophage-migration inhibitory factor (MIF), which is mainly produced by macrophages has been shown to have a pathogenetic role in inflammatory bowel disease (IBD). We developed a technique to create an SPG complex that highly conformed to the antisense MIF. The administration of antisense MIF/SPG complex effectively suppressed MIF production and significantly ameliorated intestinal inflammation. Our result demonstrated a possible new therapeutic approach, i.e., the administration of antisense MIF/SPG complex, for the treatment of IBD.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Doenças Inflamatórias Intestinais/terapia , Oligonucleotídeos Antissenso/administração & dosagem , Sizofirano/química , Animais , Células Cultivadas , Colite/induzido quimicamente , Colite/metabolismo , Colite/terapia , Citocinas/metabolismo , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Feminino , Humanos , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/metabolismo , Mucosa Intestinal , Lectinas Tipo C/metabolismo , Fatores Inibidores da Migração de Macrófagos/química , Fatores Inibidores da Migração de Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Oligonucleotídeos Antissenso/química , Sizofirano/administração & dosagem
12.
J Ind Microbiol Biotechnol ; 40(1): 105-12, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23090286

RESUMO

Schizophyllan is a homoglucan produced by the fungus Schizophyllum commune, with a ß-1,3-linked backbone and ß-1,6-linked side chains of single glucose units at every other residue. Schizophyllan is commercially produced for pharmaceutical and cosmetics uses. However, the unique physical properties of schizophyllan suggest that it may have biomaterials applications. Schizophyllan is conventionally produced by submerged culture fermentation using glucose as a carbon source. This study demonstrates for the first time the efficient utilization of agricultural biomass substrates, particularly distiller's dried grains with solubles, for schizophyllan production. Sugar composition analysis, NMR, and permethylation linkage analysis confirmed that the recovered product was schizophyllan. Schizophyllan produced from agricultural residues was of a high molecular weight and exhibited solution viscosity properties similar to those of commercially produced material. Utilization of biomass substrates could reduce the cost of schizophyllan production and provide a new value-added bioproduct for integrated biorefineries of the future.


Assuntos
Sizofirano/biossíntese , Biomassa , Biopolímeros/biossíntese , Biopolímeros/química , Produtos Agrícolas , Fermentação , Espectroscopia de Ressonância Magnética , Schizophyllum/metabolismo , Sizofirano/química , Viscosidade
13.
Int J Biol Macromol ; 252: 126544, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37634777

RESUMO

The edible split gill mushroom is considered both a nutritive and therapeutic superfood, as well as rich in schizophyllan and protein. Prebiotic properties and other biological effects distinguish the schizophyllan (ß-glucan). Thus, this research investigates the identity of the mushroom strain, the nutritional composition of this mushroom, and the schizophyllan extract for further analysis, including its prebiotic activity and so on. The experimental results revealed that this mushroom was identified as Schizophyllum commune, comprising more excellent carbohydrates, protein, crude fiber, lower fat, and no heavy metal detection. Moreover, this extract consisted of pharmaceutical hydrophobin (14.0-18.5 kDa), lectin protein (21-35 kDa), bioactive purpurin or red pigment, including the prebiotic ß-glucan stimulating the proliferation of probiotic bacteria isolated from yogurt. Therefore, both S. commune and the schizophyllan extract can be used as a prebiotic candidate, functional food, and nutraceutical product.


Assuntos
Schizophyllum , Sizofirano , beta-Glucanas , Animais , Sizofirano/química , Schizophyllum/metabolismo , Brânquias , beta-Glucanas/farmacologia , beta-Glucanas/metabolismo , Fatores Biológicos
14.
Carbohydr Polym ; 252: 117132, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33183591

RESUMO

Transdermal immunomodulation is of increasing interest as an efficient drug delivery method. It non-invasively delivers drugs directly to skin-resident immune cells, thereby avoiding the first-pass metabolism. Herein, we prepared ovalbumin-conjugated hyaluronic acid-methacrylate (HAMA-OVA) and schizophyllan-methacrylate (SPGMA) hybrid nanogels and investigated their suitability for topical delivery. The particle size was controlled to between 100 and 300 nm using ultrasonication and filtering processes. The nanogels penetrated the porcine stratum corneum layer and were deposited in the dermis via hybridization with HAMA. In addition, the hybridized SPGMA promoted the internalization of the nanogels into dendritic cells (DCs; JAWSII), which resulted in an improvement in the ovalbumin delivery efficiency. In molecular biological assessments, the hybrid nanogels upregulated the DC activation marker interleukin-6 and induced DC maturation, indicating antigen-presenting behavior. These results suggest that HAMA/SPGMA hybrid nanogels are a promising topical delivery carrier for immunomodulation and vaccinations.


Assuntos
Células Dendríticas/efeitos dos fármacos , Portadores de Fármacos/química , Nanogéis/química , Administração Cutânea , Animais , Linhagem Celular , Ácido Hialurônico/química , Fatores Imunológicos/química , Imunomodulação , Metacrilatos/química , Camundongos , Ovalbumina/química , Estudo de Prova de Conceito , Sizofirano/química , Absorção Cutânea , Suínos , beta-Glucanas/química
15.
Int Immunopharmacol ; 90: 107181, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33249044

RESUMO

Unmethylated CpG motifs with phosphothioate backbone trigger TLR9 to elicit innate immune response characterized by the production of Th1 cytokines. The use of CpG DNA as an adjuvant has established its role in potentiating the humoral and cell mediated vaccine specific immune response. However, none of the synthetic oligodeoxynucleotides (ODNs) know and used till date are associated with the parasite itself. Our group identified a novel CG rich sequence of 14 base pairs from Leishmania donovani genome (Ld CpG ODN) and established it as a TLR9 agonist. The present study was designed to ascertain the adjuvanticity of Ld CpG ODN with soluble leishmanial antigen in experimental model of L. donovani. During the study Schizophyllan (SPG), a fungal polymer was used for encapsulating Ld CpG ODN for efficient endosomal delivery. The synthesized nanovehicles were of nearly 100 nm and localized within endosomes as confirmed by confocal microscopy. Immunization studies displayed the superior ability of synthesized nanovehicles co-administered with parasite antigen in augmenting innate immune response in comparison to ODN, nanoparticles or soluble antigen alone. The response included generation of ROS, NO and iNOS expression followed by proinflammatory cytokine milieu with reduced parasitic load within liver, spleen and bone marrow. These immune-tailored particles in combination with parasitic antigens elicited significant generation of cell mediated response owing to the presence of high levels of CD8+ T-cells and lymphocyte proliferation. Moreover, vaccination regime with synthesized adjuvant also activated humoral immunity by escalating the levels of IgG2 followed by reduced levels of anti-leishmanial IgG and IgG1 antibodies. The findings support the efficacy of Ld CpG ODN as a potential adjuvant against visceral leishmaniasis.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Antígenos de Protozoários/administração & dosagem , Leishmania donovani/imunologia , Leishmaniose Visceral/prevenção & controle , Nanopartículas , Oligodesoxirribonucleotídeos/administração & dosagem , Vacinas Protozoárias/administração & dosagem , Sizofirano/administração & dosagem , Adjuvantes Imunológicos/química , Animais , Antígenos de Protozoários/química , Modelos Animais de Doenças , Composição de Medicamentos , Interações Hospedeiro-Patógeno , Imunidade Celular/efeitos dos fármacos , Imunidade Humoral/efeitos dos fármacos , Imunogenicidade da Vacina , Leishmania donovani/patogenicidade , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/parasitologia , Masculino , Mesocricetus , Oligodesoxirribonucleotídeos/química , Vacinas Protozoárias/química , Sizofirano/química , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/parasitologia , Receptor Toll-Like 9/agonistas , Receptor Toll-Like 9/metabolismo , Vacinação
16.
Bioorg Chem ; 38(6): 260-4, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20673953

RESUMO

Most of antisense oligonucleotides (ASOs) subjected to current clinical evaluation belong to phosphorothioate (PS) analogues. Although PS has great advantage in DNase resistance, it can induce nonspecific side-effects. Thus it is important to investigate the influence of ASOs with different PS contents. In this paper, we prepared the complex consisting of schizophyllan (SPG) and ASOs attached a dA40 tail with different PS contents to the 3' end of the ODN, which is introduced to stabilize the complex with SPG. With increase of PS content in the dA40, its complexation ability with SPG was improved and the complex showed high thermal stability. The thermal stability of the fully phosphorothioated ASOs was obtained by only replacing 20% of the oxygen of the phosphodiester moiety. The ability of gene suppression between PS and phosphodiester for antisense sequences was almost the same, indicating that the antisense sequences need not to be PS backbone. These data may provide new insight for the interaction between ß-1,3-glucan and DNA and help to deliver therapeutic ODNs.


Assuntos
Genes Supressores , Oligonucleotídeos Antissenso/química , Oligonucleotídeos Antissenso/farmacologia , Oligonucleotídeos Fosforotioatos/química , Oligonucleotídeos Fosforotioatos/farmacologia , Sizofirano/química , Sizofirano/farmacologia , Animais , Sequência de Bases , Células Cultivadas , Inativação Gênica , Camundongos , Camundongos Endogâmicos C57BL , Schizophyllum/química , Temperatura , Fator de Necrose Tumoral alfa/genética , beta-Glucanas/química
17.
Carbohydr Polym ; 240: 116263, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32475555

RESUMO

Schizophyllan is a natural polysaccharide that has shown great potential as enhanced oil recovery (EOR) polymer for high-temperature, high-salinity reservoirs. Nevertheless, the adsorption behavior of schizophyllan over carbonate minerals remains ambiguous element towards its EOR applications. Here, we investigate the adsorption of schizophyllan on different carbonate minerals. The effect of mineral type, salinity, and background ions on adsorption is analyzed. Our results indicate the adsorption capacity is higher on calcite and dolomite compared to silica and kaolin and the adsorption capacity decreases with salinity. Moreover, the adsorption kinetics follows pseudo-second order mechanism regardless of the mineral type. Adsorption over calcite is diminished in presence of water structure making ions and enhanced in presence of structure breaking ion and in presence of urea. Gel permeation chromatography results reveal the preferential adsorption of longer chains. The adsorption over carbonate minerals proceed via complex formation between polymer molecule and mineral surface.


Assuntos
Minerais/sangue , Sizofirano/química , Adsorção , Cinética
18.
Int J Biol Macromol ; 144: 380-388, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31837368

RESUMO

In this study, following encapsulation of ellagic acid (EA), an anti-cancer agent, loaded in schizophyllan (EA/SPG-NP) and chitin (EA/Ch-NP) nanoparticles, its release in 95% ethanol, and different mediums of digestive systems with pH ranging 1.5 to 7.4, were examined before investigating for treatment of breast cancer MCF-7cells. Following synthesis, the EA was characterized by FT-IR, SEM, XRD, DLS and zeta potential analysis. Loading capacity of schizophyllan and chitin were 30.08 and 79.52%, respectively, while SEM images indicated respective size distributions of 217.8 and 39.82 nm, with the corresponding zeta potentials being +27 and -9.14 mV. As EA was loaded in nanoparticles, antioxidant activity, examined by DPPH method, of the free EA was found to be higher than both EA/SPG-NP and EA/Ch-NP, but lower than the latter at 7.4 pH. Interestingly, scavenging activities for EA and EA/SPG-NP reduced for higher pH. The MTT cytotoxicity indicated that EA/SPG-NP and EA/Ch-NP inhibited effectively cell growth of breast cancer cell lines at IC50 of 60 and 115 µg/ml, respectively.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Quitina/química , Ácido Elágico/administração & dosagem , Nanopartículas/química , Sizofirano/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Células MCF-7
19.
Carbohydr Polym ; 229: 115555, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31826421

RESUMO

The water-soluble ß-glucan schizophyllan has diverse immunomodulatory activities. However, its biological activities have only been explored using cells grown in two-dimensional (2D) culture condition, which does not replicate the three-dimensional (3D) microenvironment of actual tissue, resulting in mismatches between in vitro and in vivo findings. In this study, we investigated the immunomodulatory effects of ultrasonicated schizophyllan (uSPG) on RAW264.7 cells encapsulated in 3D poly(ethylene glycol) hydrogel. Cells grown in 3D were less sensitive to uSPG than those grown in 2D, although uSPG upregulated M1 macrophage phenotype markers in both conditions. This might be due to the low availability of uSPG recognition receptors of cells grown in 3D. Conversely, uSPG promoted gene expressions of M2 macrophage phenotype markers in 3D, suggesting uSPG-induced immune-regulation of macrophages in real tissues. These findings imply that the immunomodulatory effects of uSPG on macrophages should be carefully interpreted in terms of the microenvironment.


Assuntos
Hidrogéis/química , Sizofirano/química , Animais , Técnicas de Cultura de Células , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Expressão Gênica/efeitos dos fármacos , Hidrogéis/farmacologia , Lipopolissacarídeos/toxicidade , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Oligopeptídeos/química , Polietilenoglicóis/química , Células RAW 264.7 , Sizofirano/farmacologia , Sonicação
20.
Carbohydr Polym ; 229: 115383, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31826529

RESUMO

In this study, a novel hydrogel composed of bacterial cellulose (BC) and schizophyllan (SPG) biopolymers with improved mechanical, swelling and antibacterial properties was developed. BC was firstly functionalized using 3-aminopropyl triethoxysilane (APTES) to provide better interaction with SPG. A diffraction peak at 5.7° in the XRD pattern of amine-grafted BC/SPG membrane revealed the intercalation of SPG into BC network. SEM images of amine-grafted BC/SPG showed that the fibrillar network of BC was totally covered with schizophyllan. Two distinct stages of weight loss in TGA thermo-gram of amine grafted BC/SPG verified the successful entrance of SPG into BC fibrils. Tensile strength of the amine-grafted BC/SPG considerably increased to 42.19 ±â€¯7.16 MPa as compared to neat BC (4.41 ± 0.38 MPa) and amine-grafted BC (7.90 ±â€¯0.71 MPa). It also showed the highest swelling degree (800 ±â€¯80%). Amine-grafted BC/SPG exhibited moderate antibacterial activity. MTT assay showed that amine-grafted BC/SPG stimulated the proliferation of normal human fibroblast cells.


Assuntos
Antibacterianos/química , Celulose/química , Hidrogéis/química , Sizofirano/química , Aminação , Antibacterianos/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Celulose/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Fibroblastos/efeitos dos fármacos , Humanos , Hidrogéis/farmacologia , Schizophyllum/metabolismo , Sizofirano/metabolismo , Sizofirano/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
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