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1.
Carbohydr Polym ; 333: 121976, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38494228

RESUMO

White tea, one of the six traditional teas in China, is made only through natural withering and low-temperature drying processes. It demonstrates diverse pharmacological and health-promoting effects, including antioxidant, antiviral, anticancer, and hypolipidemic activities. Despite the significance of polysaccharides in white tea leaves, their fine structure and physiological functions remain unexplored. In this study, the polysaccharide fragment WTP-80a with anticancer activity was isolated and purified from white tea through water extraction, alcohol precipitation, DEAE-52 ion exchange column chromatography, and sephacryl S-200 dextran gel column chromatography. WTP-80a exhibited a molecular weight of 1.14 × 105 Da and consisted of galactose (Gal), arabinose (Ara), rhamnose (Rha), and glucuronic acid (Glc-UA). The main chain skeleton of WTP-80a contained 3,6)-ß-Galp-(1→, 3)-α-Galp-(1→, 5)-α-Araf-(1 â†’ and 3)-α-Glcp-UA-(1→. Branch chains included α-Araf-(1 â†’ and ß-Rhap-(1 â†’ connected to the C3 and C6 positions of →3,6)-ß-Galp-(1→, respectively. In vitro anticancer experiments revealed that WTP-80a effectively hindered the proliferation, colony formation, migration, and invasion of B16F10 cells. Additionally, it induced apoptosis in B16F10 cells by blocking the G2/M phase, increasing active oxygen content, and reducing mitochondrial membrane potential. These findings provide a solid theoretical foundation for the application of white tea polysaccharides as anticancer products.


Assuntos
Galactose , Polissacarídeos , Polissacarídeos/química , Galactose/análise , Ramnose , Ácido Glucurônico , Chá
2.
ACS Appl Mater Interfaces ; 16(8): 9799-9815, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38380628

RESUMO

This study introduces a dendronized pressure-sensitive adhesive, TMPE@Rha, addressing Food and Drug Administration (FDA) concerns about traditional pressure-sensitive adhesives (PSAs) in transdermal drug delivery systems. The unique formulation, composed of rhamnose, trihydroxypropane, and poly(ethylene glycol), significantly enhances cohesion and tissue adhesion. Leveraging rhamnose improves intermolecular interactions and surface chain mobility, boosting tissue adhesion. Compared to acrylic pressure-sensitive adhesive 87-DT-4098, TMPE@Rha shows substantial advantages, with up to 5 to 6 times higher peel strength on porcine and wood substrates. Importantly, it maintains strong human skin adhesion beyond 7 days without the typical "dark ring" phenomenon. When loaded with diclofenac, the adhesive exhibits 3.12 times greater peeling strength than commercial alternatives, sustaining human adhesion for up to 6 days. Rigorous analyses confirm rhamnose's role in increasing interaction strength. In vitro studies and microscopy demonstrate the polymer's ability to enhance drug loading and distribution on the skin, improving permeability. Biocompatibility tests affirm TMPE@Rha as nonirritating. In summary, TMPE@Rha establishes a new standard for PSAs in transdermal drug delivery systems, offering exceptional adhesion, robustness, and biocompatibility. This pioneering work provides a blueprint for next-generation, highly adhesive, drug-loaded PSAs that meet and exceed FDA criteria.


Assuntos
Dendrímeros , Humanos , Animais , Suínos , Ramnose , Aderências Teciduais , Administração Cutânea , Pele , Preparações Farmacêuticas , Adesivos/química , Sistemas de Liberação de Medicamentos
3.
Carbohydr Res ; 536: 109038, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219633

RESUMO

Therapeutic monoclonal antibodies (mAbs) against the epidermal growth factor receptor (EGFR) have shown clinical efficacy in colorectal cancer and other solid cancers. Enhancing the effector functions of these anti-EGFR mAbs is believed to be a valuable approach to achieve improved efficacy in clinical setting. Here, we report the development of an effector function-enhanced antibody by rhamnose (Rha) functionalization. Cetuximab, a human/mouse chimeric anti-EGFR mAb, was selected and site-specifically conjugated with Rha haptens. The obtained cetuximab-Rha conjugate was shown to be able to selectively redirect amounts of endogenous anti-Rha antibodies onto EGFR-positive solid tumor cells and thereby provide more Fc domains to achieve enhancement of effector functions including complement-dependent cytotoxicity (CDC) and antibody-dependent cell-mediated phagocytosis (ADCP). Particularly, CDC, one powerful cell killing mechanism which is inactive in cetuximab, was dramatically improved. This study demonstrates the potential of rhamnose-modified antibody for EGFR-positive solid tumor immunotherapy.


Assuntos
Antineoplásicos , Ramnose , Animais , Humanos , Camundongos , Cetuximab/farmacologia , Ramnose/farmacologia , Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Receptores ErbB , Linhagem Celular Tumoral
4.
Adv Sci (Weinh) ; 11(13): e2307613, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38286668

RESUMO

Cetuximab resistance is a significant challenge in cancer treatment, requiring the development of novel therapeutic strategies. In this study, a series of multivalent rhamnose (Rha)-modified nanobody conjugates are synthesized and their antitumor activities and their potential to overcome cetuximab resistance are investigated. Structure-activity relationship studies reveal that the multivalent conjugate D5, bearing sixteen Rha haptens, elicits the most potent innate fragment crystallizable (Fc) effector immunity in vitro and exhibits an excellent in vivo pharmacokinetics by recruiting endogenous antibodies. Notably, it is found that the optimal conjugate D5 represents a novel entity capable of reversing cetuximab-resistance induced by serine protease (PRSS). Moreover, in a xenograft mouse model, conjugate D5 exhibits significantly improved antitumor efficacy compared to unmodified nanobodies and cetuximab. The findings suggest that Rha-Nanobody (Nb) conjugates hold promise as a novel therapeutic strategy for the treatment of cetuximab-resistant tumors by enhancing the innate Fc effector immunity and enhancing the recruitment of endogenous antibodies to promote cancer cell clearance by innate immune cells.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Receptores ErbB , Ramnose , Anticorpos de Domínio Único , Animais , Humanos , Camundongos , Anticorpos Monoclonais Humanizados/uso terapêutico , Linhagem Celular Tumoral , Cetuximab/farmacologia , Cetuximab/uso terapêutico , Receptores ErbB/imunologia , Imunidade Inata , Anticorpos de Domínio Único/farmacologia , Resistencia a Medicamentos Antineoplásicos/imunologia
5.
Molecules ; 28(18)2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37764243

RESUMO

In order to investigate the antioxidant activity of Elaeagnus umbellata polysaccharides, the physicochemical characteristics of purified Elaeagnus umbellata polysaccharides (EUP, consisting of two fractions, EUP1 and EUP2) were investigated using UV spectrophotometry, high-performance liquid chromatography (HPLC), high-performance gel permeation chromatography (HPGPC), and Fourier transform infrared spectroscopy (FT-IR). This revealed that EUP1 and EUP2 were acidic polysaccharides with an average molecular weight (MW) of 63 and 38 kDa, respectively. EUP1 mainly consisted of L-rhamnose and D-galactose in a molar ratio of 2.05:1, and EUP2 consisted of D-mannose, L-rhamnose, D-galactose, and D-arabinose in a molar ratio of 2.06:1:2.78:1. Furthermore, EUP exhibited considerable antioxidant potential for scavenging hydroxyl, superoxide anion, DPPH, and ABTS radicals. Therefore, EUP can be developed as a potential antioxidant for the functional food or pharmaceutical field.


Assuntos
Antioxidantes , Elaeagnaceae , Antioxidantes/farmacologia , Galactose , Ramnose , Espectroscopia de Infravermelho com Transformada de Fourier , Polissacarídeos/farmacologia
6.
Int J Biol Macromol ; 253(Pt 3): 126763, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37703985

RESUMO

Rhamnose methylation of spinosyn critical for insecticidal activity is orchestrated by substrate specificity of three S-adenosyl-L-methionine (SAM) dependent methyltransferases (MTs). Previous in vitro enzymatic assays indicate that 3'-O-MT SpnK accepts the rhamnosylated aglycone (RAGL) and 2'-O-methylated RAGL as substrates, but does not tolerate the presence of a methoxy moiety at the O-4' position of the rhamnose unit. Here we solved the crystal structures of apo and ligand-bound SpnK, and used molecular dynamic (MD) simulations to decipher the molecular basis of substrate specificity. SpnK assembles into a tetramer, with each set of three monomers forming an integrated substrate binding pocket. The MD simulations of SpnK complexed with RAGL or 2'-O-methylated RAGL revealed that the 4'-hydroxyl of the rhamnose unit formed a hydrogen bond with a conserved Asp299 of the catalytic center, which is disrupted in structures of SpnK complexed with 4'-O-methylated RAGL or 2',4'-di-O-methylated RAGL. Comparison with SpnI methylating the C2'-hydroxyl of RAGL reveals a correlation between a DLQT/DLWT motif and the selectivity of rhamnose O-MTs. Together, our structural and computational results revealed the structural basis of substrate specificity of rhamnose O-MTs and would potentially help the engineering of spinosyn derivatives.


Assuntos
Metiltransferases , Ramnose , Metilação , Ramnose/química , Metiltransferases/química , Catálise , Simulação de Dinâmica Molecular , Especificidade por Substrato
7.
Molecules ; 28(15)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37570747

RESUMO

Misgurnus anguillicaudatus, also known as oriental weather loach, is widely consumed and favored in East Asia due to its superior nutritional values and excellent flavor. In this study, a crude Misgurnus anguillicaudatus carbohydrates (MAC) was isolated from Misgurnus anguillicaudatus. Subsequently, two parts, which were named MAO and MAP, respectively, were separated from MAC, and their primary structures and immunomodulatory activity were investigated. The results showed that MAO had a molecular weight of 2854 Da, and principally consisted of arabinose (77.11%) and rhamnose (21.97%), together with minor levels of fucose (0.92%); MAP, with a molecular weight of 3873 Da, was mainly composed of fucose (87.55%) and a small amount of rhamnose (8.86%) and galactose (3.59%). The in vitro assay showed that MAC could significantly enhance the proliferation of macrophages without cytotoxicity and increase the production of immune substances (TNF-α, IL-6). Together with Western blot results, we speculated that MAC could stimulate RAW264.7 murine macrophage cells to secrete TNF-α and IL-6 through up-regulating TLR4-MAPK-p38 signaling pathways. The results indicated that MAC could be a potential immune agent and might provide meaningful information for further chain conformation and immune mechanism research.


Assuntos
Cipriniformes , Fucose , Animais , Camundongos , Interleucina-6 , Ramnose , Fator de Necrose Tumoral alfa , Monoaminoxidase
8.
J Nat Prod ; 86(8): 1939-1949, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37497692

RESUMO

A convenient synthesis is presented for a new class of bioactive bifunctionalized conjugates of lupane-type triterpenoids with triphenylphosphonium (TPP) and glycopyranosyl targeting moieties. The main synthesis steps include glycosylation of haloalkyl esters of the triterpene acid at the C-3 position by the imidate derivatives of glycopyranose followed by the product modification at the C-28 position with triphenylphosphine. The conjugates of betulinic acid (BetA) with TPP and d-glucose, l-rhamnose, or d-mannose moieties were thus synthesized as potential next-generation BetA-derived anticancer compounds. LC-MS/MS analysis in glucose-free physiological solution indicated that the glycosides showed better accumulation in PC-3 prostate cancer cells than both BetA and TPP-BetA conjugate, while the transporting effect of monosaccharide residues increased as follows: d-mannose < l-rhamnose ≈ d-glucose. At saturated concentrations, the glycosides caused a disturbing effect on mitochondria with a more drastic drop in transmembrane potential but weaker overproduction of mitochondrial reactive oxygen species (ROS) compared to TPP-BetA conjugate. Cytotoxicity of the glycosides in culture medium was comparable with or higher than that of the nonglycosylated conjugate, depending on the cancer cell line, whereas the compounds were less active toward primary fibroblasts. Glycosylation tended to increase pro-apoptotic and decrease pro-autophagic activities of the BetA derivatives. Cytotoxicity of the synthesized glycosides was considered in comparison with the summarized data on the natural and modified BetA glycosides. The results obtained are important for the development of bifunctionalized conjugates of triterpenoids with an increased cancer cell targetability.


Assuntos
Neoplasias , Triterpenos , Masculino , Humanos , Ácido Betulínico , Manose , Cromatografia Líquida , Ramnose , Espectrometria de Massas em Tandem , Triterpenos/farmacologia , Triterpenos/química , Glicosídeos
9.
Molecules ; 28(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37175182

RESUMO

The use of radiolabeled glucose for PET imaging resulted in the most commonly used tracer in the clinic, 2-deoxy-2-[18F]fluoroglucose (FDG). More recently, other radiolabeled sugars have been reported for various applications, including imaging tumors and infections. Therefore, in this study, we developed a series of fluorine-18-labeled L-rhamnose derivatives as potential PET tracers of various fungal and bacterial strains. Acetyl-protected triflate precursors of rhamnose were prepared and radiolabeled with fluorine-18 followed by hydrolysis to produce L-deoxy [18F]fluororhamnose. The overall radiochemical yield was 7-27% in a 90 min synthesis time with a radiochemical purity of 95%. In vivo biodistribution of the ligands using PET imaging showed that 2-deoxy-2-[18F]fluoro-L-rhamnose is stable for at least up to 60 min in mice and eliminated via renal clearance. The tracer also exhibited minimal tissue or skeletal uptake in healthy mice resulting in a low background signal.


Assuntos
Radioisótopos de Flúor , Ramnose , Camundongos , Animais , Distribuição Tecidual , Linhagem Celular Tumoral , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos
10.
Blood Adv ; 7(17): 5137-5151, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37083597

RESUMO

Intestinal permeability may correlate with adverse outcomes during hematopoietic stem cell transplantation (HSCT), but longitudinal quantification with traditional oral mannitol and lactulose is not feasible in HSCT recipients because of mucositis and diarrhea. A modified lactulose:rhamnose (LR) assay is validated in children with environmental enteritis. Our study objective was to quantify peri-HSCT intestinal permeability changes using the modified LR assay. The LR assay was administered before transplant, at day +7 and +30 to 80 pediatric and young adult patients who received allogeneic HSCT. Lactulose and rhamnose were detected using urine mass spectrometry and expressed as an L:R ratio. Metagenomic shotgun sequencing of stool for microbiome analyses and enzyme-linked immunosorbent assay analyses of plasma lipopolysaccharide binding protein (LBP), ST2, REG3α, claudin1, occludin, and intestinal alkaline phosphatase were performed at the same timepoints. L:R ratios were increased at day +7 but returned to baseline at day +30 in most patients (P = .014). Conditioning regimen intensity did not affect the trajectory of L:R (P = .39). Baseline L:R ratios did not vary with diagnosis. L:R correlated with LBP levels (r2 = 0.208; P = .0014). High L:R ratios were associated with lower microbiome diversity (P = .035), loss of anaerobic organisms (P = .020), and higher plasma LBP (P = .0014). No adverse gastrointestinal effects occurred because of LR. Intestinal permeability as measured through L:R ratios after allogeneic HSCT correlates with intestinal dysbiosis and elevated plasma LBP. The LR assay is well-tolerated and may identify transplant recipients who are more likely to experience adverse outcomes.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Lactulose , Adulto Jovem , Humanos , Criança , Lactulose/metabolismo , Ramnose , Reação de Fase Aguda , Disbiose , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Permeabilidade
11.
J Am Chem Soc ; 145(18): 10022-10034, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37099481

RESUMO

We provide evidence for CH-based nonconventional hydrogen bonds (H-bonds) for 10 Lewis antigens and two of their rhamnose analogues. We also characterize the thermodynamics and kinetics of the H-bonds in these molecules and present a plausible explanation for the presence of nonconventional H-bonds in Lewis antigens. Using an alternative method to simultaneously fit a series of temperature-dependent fast exchange nuclear magnetic resonance (NMR) spectra, we determined that the H-bonded conformation is favored by ∼1 kcal/mol over the non-H-bonded conformation. Additionally, a comparison of temperature-dependent 13C linewidths in various Lewis antigens and the two rhamnose analogues reveals H-bonds between the carbonyl oxygen of the N-acetyl group of N-acetylglucosamine and the OH2 group of galactose/fucose. The data presented herein provide insight into the contribution of nonconventional H-bonding to molecular structure and could therefore be used for the rational design of therapeutics.


Assuntos
Antígenos do Grupo Sanguíneo de Lewis , Ramnose , Ligação de Hidrogênio , Termodinâmica , Polissacarídeos , Hidrogênio
12.
Angew Chem Int Ed Engl ; 62(25): e202303750, 2023 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-37042088

RESUMO

We propose a de novo glycan display approach that combines metabolic labeling and a glycan-caging strategy as a facile editing method for cell-surface glycans. This method enables the introduction of antigen glycans onto cancer cells to induce immune responses through antibody recruiting. The caging strategy prevents the capture of α-rhamnose (an antigen glycan) by endogenous antibodies during the introduction of the glycan to the targeted cell surface, and subsequent uncaging successfully induces immune responses. Therefore, this study proposes a practical method for editing the cell-surface glycocalyx under promiscuous conditions, such as those in vivo, which paves the way for the development of glycan function analysis and regulation.


Assuntos
Anticorpos , Polissacarídeos , Polissacarídeos/metabolismo , Membrana Celular/metabolismo , Ramnose
13.
Food Chem ; 409: 135264, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-36571899

RESUMO

A novel bioactive polysaccharopeptide (C1) and polysaccharide (C2) with an average molecular weight of 180 kDa and 70 kDa were isolated from R. rugosa pseudofruit. The composition of the macromolecules was established using 1H NMR, FT-IR, GC-MS, SDS-PAGE coupled with enzymatic cleavage, and proteomic analyses (LC-MS). C1 was found to contain 60.56 ± 1.82 % of sugars and 21.17 ± 0.47 % of uronic acids. Its main neutral monosaccharides were arabinose, rhamnose, galactose, glucose, fucose, and mannose. C1 was found to be a polysaccharopeptide containing pectinesterase-like protein. C2 was composed of 32.85 ± 0.97 % of sugars and 48.77 ± 1.15 % of uronic acids. Its main neutral monosaccharides were galactose, glucose, rhamnose, arabinose, and mannose. A promising nutraceutical value of the polysaccharides was revealed. Assays showed strong α-glucosidase inhibitory activity of both macromolecules and considerable antiradical potential and moderate lipoxygenase inhibitory activity of the crude polysaccharide. Moreover, antiproliferative activity of C2 was observed.


Assuntos
Galactose , Rosa , Ramnose , Rosa/química , Manose , Arabinose , Espectroscopia de Infravermelho com Transformada de Fourier , Proteômica , Monossacarídeos/química , Glucose , Polissacarídeos/química , Suplementos Nutricionais , Ácidos Urônicos/química , Peptídeos/farmacologia
14.
Biotechnol Appl Biochem ; 70(3): 1035-1043, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36479705

RESUMO

Spinosad, a combination of spinosyn A and D produced by Saccharopolyspora spinosa, is a highly efficient pesticide. There has been a considerable interest in the improvement of spinosad production because of a low yield achieved by wild-type S. spinosa. In this study, we designed and constructed a pIBR-SPN vector. pIBR-SPN is an integrative vector that can be used to introduce foreign genes into the chromosome of S. spinosa. Different combinations of genes encoding forasamine and rhamnose were synthesized and used for the construction of different recombinant plasmids. The following recombinant strains were developed: S. spinosa pIBR-SPN (only the vector), S. spinosa pIBR-SPN F (forosamine genes), S. spinosa pIBR-SPN R (rhamnose genes), S. spinosa pIBR-SPN FR (forosamine and rhamnose genes), S. spinosa pIBR-SPN FRS (forosamine, rhamnose, and SAM [S-adenosyl-L-methionine synthetase] genes), and S. spinosa MUV pIBR-SPN FR. Among these recombinant strains, S. spinosa pIBR-SPN FR produced 1394 ± 163 mg/L spinosad, which was 13-fold higher than the wild-type. S. spinosa MUV pIBR-SPN FR produced 1897 (±129) mg/L spinosad, which was seven-fold higher than S. spinosa MUV and 17-fold higher than the wild-type strain.


Assuntos
Engenharia Metabólica , Saccharopolyspora , Ramnose/metabolismo , Saccharopolyspora/genética , Saccharopolyspora/metabolismo , Combinação de Medicamentos
15.
Med Sci Sports Exerc ; 55(1): 141-150, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36069803

RESUMO

PURPOSE: The purpose of this study was to evaluate the effects of acute ibuprofen consumption (2 × 600-mg doses) on markers of enterocyte injury, intestinal barrier dysfunction, inflammation, and symptoms of gastrointestinal (GI) distress at rest and after exercise in hypobaric hypoxia. METHODS: Using a randomized double-blind placebo-controlled crossover design, nine men (age, 28 ± 3 yr; weight, 75.4 ± 10.5 kg; height, 175 ± 7 cm; body fat, 12.9% ± 5%; V̇O 2 peak at 440 torr, 3.11 ± 0.65 L·min -1 ) completed a total of three visits including baseline testing and two experimental trials (placebo and ibuprofen) in a hypobaric chamber simulating an altitude of 4300 m. Preexercise and postexercise blood samples were assayed for intestinal fatty acid binding protein (I-FABP), ileal bile acid binding protein, soluble cluster of differentiation 14, lipopolysaccharide binding protein, monocyte chemoattractant protein-1, tumor necrosis factor α (TNF-α), interleukin-1ß, and interleukin-10. Intestinal permeability was assessed using a dual sugar absorption test (urine lactulose-to-rhamnose ratio). RESULTS: Resting I-FABP (906 ± 395 vs 1168 ± 581 pg·mL -1 ; P = 0.008) and soluble cluster of differentiation 14 (1512 ± 297 vs 1642 ± 313 ng·mL -1 ; P = 0.014) were elevated in the ibuprofen trial. Likewise, the urine lactulose-to-rhamnose ratio (0.217 vs 0.295; P = 0.047) and the preexercise to postexercise change in I-FABP (277 ± 308 vs 498 ± 479 pg·mL -1 ; P = 0.021) were greater in the ibuprofen trial. Participants also reported greater upper GI symptoms in the ibuprofen trial ( P = 0.031). However, monocyte chemoattractant protein-1 ( P = 0.007) and TNF-α ( P = 0.047) were lower throughout the ibuprofen trial compared with placebo (main effect of condition). CONCLUSIONS: These data demonstrate that acute ibuprofen ingestion aggravates markers of enterocyte injury and intestinal barrier dysfunction at rest and after exercise in hypoxia. However, ibuprofen seems to suppress circulating markers of inflammation.


Assuntos
Exercício Físico , Gastroenteropatias , Ibuprofeno , Descanso , Adulto , Humanos , Masculino , Quimiocina CCL2 , Hipóxia , Ibuprofeno/farmacologia , Inflamação , Lactulose/urina , Ramnose/urina , Fator de Necrose Tumoral alfa
16.
Food Chem ; 401: 134211, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36122490

RESUMO

Dendrobium officinale is widely consumed owing to its numerous beneficial effects. We aimed to characterize polysaccharides of Dendrobium officinale (DOP) from the stems of Dendrobium officinale Xianhu 2 and clarify whether it benefit the intestinal microbiota and the immune system. The DOP weighed 291 kDa and comprised mannose, glucose, galactose, and rhamnose at 59.31:33.31:1.00:0.51 M ratio. In in vitro/vivo studies, DOP significantly increased benign intestinal microbe proportion (Lactobacillus, etc.), but reduced harmful bacteria (Escherichia_Shigella) (P < 0.05), and significantly increased butyric acid production (P < 0.05). Concentrations of 2 g/L DOP for in vitro fermentation and 100 mg/kg body weight for the mouse model were effective. In mice, DOP significantly reduced CRP, CD3, CD4, and TNF-α levels and increased C4 levels (P < 0.05). DOP might influence the immune system indirectly through regulation of the gut microbiota. Its possible regulation mechanism was that DOP reduced CD4+ Th cells proliferation so that reduced the secretion of TNF-α.


Assuntos
Dendrobium , Microbioma Gastrointestinal , Camundongos , Animais , Manose , Fator de Necrose Tumoral alfa , Galactose , Ramnose , Ácido Butírico , Polissacarídeos , Carboidratos da Dieta , Glucose , Sistema Imunitário
17.
Glycoconj J ; 39(6): 759-772, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36342595

RESUMO

In this study, a water-soluble polysaccharide from Eucommia folium was extracted by hot water and purified using Sephadex G-200 gel columns. The results showed that the purified fraction (EFP) has a molecular weight of 9.98 × 105 Da and consisted of rhamnose, arabinose, galactose, glucose, mannose, xylose, galacturonic acid, and glucuronic acid (molar ratio: 0.226: 1.739: 2.183: 1: 0.155: 0.321: 0.358: 0.047). The combination of infrared spectroscopy and NMR analysis proved that EFP is an acidic polysaccharide whose main chain consists of α-L-Araf-(1 → , → 3,5)-α-Araf-(1 → , → 3)-ß-Galp-(1 → , → 3,6)-ß-Glcp-(1 → , → 2)-α-D-Manp-(1 → , → 4)-α-GalpA-(1 → , → 2,4)-α-Rhap-(1 → . In addition, the in vivo antitumoral activity of EFP was studied using a H22 tumor-bearing mice model. EFP effectively inhibited tumor growth in mice following intragastric administration. By Combining with the results of the apoptosis assay and JC-1 staining analysis, we confirmed that EFP induces apoptosis through the mitochondrial pathway. Furthermore, cell cycle analysis demonstrated that EFP blocks the cell cycle at S phase.


Assuntos
Polissacarídeos , Água , Camundongos , Animais , Polissacarídeos/química , Galactose , Ramnose , Peso Molecular
18.
Molecules ; 27(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36364003

RESUMO

The current study examines the desiccation-resistant Ramlibacter tataouinensis TTB310T as a model organism for the production of novel exopolysaccharides and their structural features. This bacterium is able to produce dividing forms of cysts which synthesize cell-bound exopolysaccharide. Initial experiments were conducted on the enrichment of cyst biomass for exopolysaccharide production under batch-fed conditions in a pilot-scale bioreactor, with lactate as the source of carbon and energy. The optimized medium produced significant quantities of exopolysaccharide in a single growth phase, since the production of exopolysaccharide took place during the division of the cysts. The exopolysaccharide layer was extracted from the cysts using a modified trichloroacetic acid method. The biochemical characterization of purified exopolysaccharide was performed by gas chromatography, ultrahigh-resolution mass spectrometry, nuclear magnetic resonance, and Fourier-transform infrared spectrometry. The repeating unit of exopolysaccharide was a decasaccharide consisting of ribose, glucose, rhamnose, galactose, mannose, and glucuronic acid with the ratio 3:2:2:1:1:1, and additional substituents such as acetyl, succinyl, and methyl moieties were also observed as a part of the exopolysaccharide structure. This study contributes to a fundamental understanding of the novel structural features of exopolysaccharide from a dividing form of cysts, and, further, results can be used to study its rheological properties for various industrial applications.


Assuntos
Comamonadaceae , Cistos , Humanos , Cromatografia Gasosa-Espectrometria de Massas , Ramnose , Polissacarídeos Bacterianos/química
19.
Sci Rep ; 12(1): 17298, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36241661

RESUMO

A novel polysaccharide EtGIPL1a was purified from fruiting bodies of Echinodontium tinctorium, a fungus unique to western North America. EtGIPL1a has an estimated weight average molecular weight of 275 kDa and is composed of glucose (54.3%), galactose (19.6%), mannose (11.1%), fucose (10.3%), glucuronic acid (4%), and rhamnose (0.6%). It has multiple glycosidic linkages, with 3-Glcp (28.9%), 6-Glcp (18.3%), 3,6-Glcp (13%), 4-GlcpA (9.2%), 6-Galp (3.9%), 2,6-Galp (2.6%), 3-Fucp (2.5%), 6-Manp (2.4%) being the most prominent, and unsubstituted glucose (15.3%), mannose (1.3%) and fucose (0.9%) as major terminal sugars. EtGIPL1a has a backbone containing mostly 3-substituted ß-glucopyranose with 4-substituted glucopyranosyluronic acid. EtGIPL1a showed anti-proliferative activity against multiple cancer cell lines, with IC50 ranging from 50.6 to 1446 nM. Flow cytometry analyses confirmed that apoptosis induction is one mechanism for its anti-proliferative activity. EtGIPL1a should be further investigated for its potential anti-cancer activity in animal models, and for its possible utility in differentiation cancer therapy.


Assuntos
Basidiomycota , Galactose , Animais , Fucose , Glucose/análise , Ácido Glucurônico , Manose , Peso Molecular , Polissacarídeos/farmacologia , Ramnose
20.
Molecules ; 27(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36296474

RESUMO

Although the fruit of Ficus tikoua Bur. has been consumed by montanic people in China for centuries, its chemical and biological composition was still unclear. A series of comprehensive investigations on its chemical constituents and bioactivities were carried out for the first time. As a result, six compounds were isolated and identified as the main components in this fruit. GC-MS analysis of the lipid components demonstrated that Ficus tikoua Bur. fruit contains some wholesome constituents such as fatty acids, vitamins, triterpenoids, and phytosterols. The fatty acids are mainly composed of linolenic acid (61.27%) and linoleic acid (22.79%). Furthermore, this fruit contains a relative high content of crude protein (9.41 ± 0.03%), total amino acids (9.28%), and total polyphenols (0.86 ± 0.01 g/100 g). The analysis of monosaccharide composition showed that the total polysaccharide mainly consists of glucose, glucuronic acid, xylose, arabinose, mannose, galactose, galacturonic acid, and rhamnose. The polysaccharide, polyphenol, water, ethanol, and flavonoid extracts exhibited prominent antioxidant activity determined by ABTS, DPPH, and FRAPS methods. Meanwhile, the total polysaccharide exhibited significant immunomodulatory effect by enhancing the release of cytokines and expression of iNOS and COX-2 in RAW264.7 cells, significantly decreasing the expression of c-Jun and p65 proteins in the cytoplasm; increasing the translocation of c-Jun and p65 to the nucleus; and regulating the phosphorylation level of Akt, PI3K, and PDK1 in the PI3K/AKT signaling pathway. This study proved that the fruit of F. tikoua is a reliable source of functional food.


Assuntos
Ficus , Fitosteróis , Triterpenos , Humanos , Ficus/química , Antioxidantes/química , Frutas/química , Polifenóis/farmacologia , Polifenóis/análise , Ciclo-Oxigenase 2 , Galactose/análise , Manose/análise , Arabinose/análise , Ramnose/análise , Xilose/análise , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Polissacarídeos/química , Flavonoides/análise , Monossacarídeos/análise , Citocinas/análise , Água/análise , Lipídeos/análise , Vitaminas/análise , Triterpenos/análise , Fitosteróis/análise , Glucose/análise , Etanol/análise , Aminoácidos/análise , Glucuronatos , Ácidos Linolênicos , Ácidos Linoleicos/análise
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