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1.
Nature ; 583(7818): 790-795, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32728239

RESUMO

Organic-inorganic hybrid perovskites have electronic and optoelectronic properties that make them appealing in many device applications1-4. Although many approaches focus on polycrystalline materials5-7, single-crystal hybrid perovskites show improved carrier transport and enhanced stability over their polycrystalline counterparts, due to their orientation-dependent transport behaviour8-10 and lower defect concentrations11,12. However, the fabrication of single-crystal hybrid perovskites, and controlling their morphology and composition, are challenging12. Here we report a solution-based lithography-assisted epitaxial-growth-and-transfer method for fabricating single-crystal hybrid perovskites on arbitrary substrates, with precise control of their thickness (from about 600 nanometres to about 100 micrometres), area (continuous thin films up to about 5.5 centimetres by 5.5 centimetres), and composition gradient in the thickness direction (for example, from methylammonium lead iodide, MAPbI3, to MAPb0.5Sn0.5I3). The transferred single-crystal hybrid perovskites are of comparable quality to those directly grown on epitaxial substrates, and are mechanically flexible depending on the thickness. Lead-tin gradient alloying allows the formation of a graded electronic bandgap, which increases the carrier mobility and impedes carrier recombination. Devices based on these single-crystal hybrid perovskites show not only high stability against various degradation factors but also good performance (for example, solar cells based on lead-tin-gradient structures with an average efficiency of 18.77 per cent).

2.
BMC Gastroenterol ; 23(1): 442, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38102560

RESUMO

BACKGROUND: Anal fistula is a common benign anorectal disease that often requires surgical intervention for effective treatment. In recent years, preoperative colonoscopy as a diagnostic tool in patients with anal fistula has garnered increasing attention due to its potential clinical application value. By investigating underlying inflammatory bowel disease (IBD), polyps, and other abnormalities, preoperative colonoscopy can offer insights to refine surgical strategies and improve patient outcomes. METHODS: This retrospective study focused on 1796 patients with various benign anorectal diseases who underwent preoperative intestinal endoscopy and met surgical criteria within the preceding three years at the First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine. Among these patients, 949 diagnosed with anal fistula comprised group A, while 847 patients without anal fistula were assigned to group B for comparison. The investigation encompassed an analysis of general patient information, endoscopic findings, polyp histopathology, distribution of bowel inflammation sites, and results of inflammatory bowel disease assessments between the two patient cohorts. A subgroup analysis was also conducted on 2275 anal fistula patients with no surgical contraindications. This subgroup was categorized into Group A (949 patients who underwent preoperative intestinal endoscopy) and Group C (1326 patients who did not undergo preoperative colonoscopy). The study compared the rates of detecting endoscopic lesions and IBD-related findings between the two subgroups. RESULTS: The study initially confirmed the comparability of general patient information between groups A and B. Notably, the abnormal detection rate in group A was significantly higher than in group B (P < 0.01). In terms of endoscopic findings, the anal fistula group (group A) exhibited higher rates of detecting bowel inflammation, inflammatory bowel disease, and polyps compared to the non-anal fistula group (group B) (P < 0.05). The distribution of inflammation locations indicated higher detection rates in the terminal ileum, ileocecal region, and ascending colon for group A compared to group B (P < 0.05). Although the incidence of IBD in group A was higher than in group B, this difference did not reach statistical significance (P > 0.05). Subsequently, the analysis of the subgroup (groups A and C) revealed a significant disparity in intestinal endoscopic detection rates (P < 0.01) and statistically significant differences in detecting IBD (P < 0.05) and Crohn's disease (P < 0.05) between the two anal fistula subgroups. CONCLUSIONS: The findings of this study underscore the substantial clinical value of preoperative colonoscopy in the comprehensive evaluation of patients with anal fistula. Preoperative colonoscopy aids in ruling out localized perianal lesions caused by underlying inflammatory bowel disease, thereby mitigating the likelihood of missed diagnoses and enhancing treatment outcomes. This research highlights the importance of incorporating preoperative colonoscopy as a valuable diagnostic tool in managing anal fistula patients.


Assuntos
Doenças Inflamatórias Intestinais , Fístula Retal , Humanos , Estudos Retrospectivos , Colonoscopia , Fístula Retal/diagnóstico , Fístula Retal/cirurgia , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/cirurgia , Inflamação
3.
Phytother Res ; 37(11): 5407-5417, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37563852

RESUMO

Angelica sinensis polysaccharide (ASP) showed increasingly recognized hepatoprotective effects and lipid regulation. Because polysaccharides are typically degraded into fragments or short-chain fatty acids in the gut, rather than being absorbed in their intact form, it is worth pondering why ASP can regulate hepatic lipid metabolism and protect the liver from damage caused by lipid accumulation. In vivo and in vitro nonalcoholic fatty liver disease (NAFLD) models with lipid accumulation were established to investigate the effect and potential mechanisms of ASP on hepatic fat accumulation. Our results showed that ASP remodeled the composition and abundance of the gut microbiota in high-fat diet-fed mice and increased their levels of propionate (0.92 ± 0.30 × 107 vs. 2.13 ± 0.52 × 107 ) and butyrate (1.83 ± 1.31 × 107 vs. 6.39 ± 1.44 × 107 ). Sodium propionate significantly increased the expression of estrogen-related receptor α (ERRα) in liver cells (400 mM sodium propionate for 2.19-fold increase) and alleviated the progress of NAFLD in methionine-choline-deficient diet model. Taken together, our study demonstrated that ASP can regulate hepatic lipid metabolism via propionate/ERRα pathway and ultimately relieving NAFLD. Our findings demonstrate that ASP can be used as a health care product or food supplement to prevent NAFLD.


Assuntos
Angelica sinensis , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Propionatos , Fígado/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/metabolismo , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL , Receptor ERRalfa Relacionado ao Estrogênio
4.
J Microencapsul ; 39(1): 25-36, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34859741

RESUMO

AIM: To prepare the hyaluronic acid-coated Olaparib-loaded PEI - PLGA nanoparticles (HA-Ola-PPNPs) and investigate their tumour-targeted anticancer effect. METHODS: The synthesis of HA-Ola-PPNPs was verified by DLS, TEM and SEM, followed was measured its cytotoxicity using CCK-8 assay. Confocal microscopy was used to observe the cellular uptake. Cell apoptosis was analysed by flow cytometry, biological SEM, and TEM. The expression of related proteins within the tumour site was investigated by immunostaining. RESULTS: The prepared HA-Ola-PPNPs showed a diameter of ∼160 nm with a negatively charged surface (-16.9 ± 2.7 mV) and sustained drug release behaviour. And the encapsulation efficiency of HA-Ola-PPNPs was 78.63 ± 5.29%. HA-Ola-PPNPs exhibited efficient in vitro and in vivo antitumor activities. HA-Ola-PPNPs induced cell apoptosis by upregulating Bax, Cytochrome C, and Caspase 3, downregulating Bcl-2 in breast cancer-bearing mice. CONCLUSIONS: According to the results, the Ola-loaded and HA-coated PEI - PLGA nanoparticles could be considered as a powerful tumour-targeted drug delivery system for TNBC treatment.


Assuntos
Nanopartículas , Neoplasias de Mama Triplo Negativas , Animais , Linhagem Celular Tumoral , Portadores de Fármacos/uso terapêutico , Humanos , Ácido Hialurônico , Camundongos , Ftalazinas , Piperazinas , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
5.
Anal Bioanal Chem ; 413(23): 5715-5724, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34291303

RESUMO

Acute alcoholic liver injury (AALI) is a threat to human health. Dendrobium officinale polysaccharide (DOP) has the potential to protect the liver by enhancing the anti-oxidative system to maintain the relative balance of ROS (active oxygen species) and antioxidants in AALI mice. However, the dynamic improvement effect of DOP on AALI is still not clear and accurate medication guidance is not available, which limits the clinical application of DOP. Because of the advantages of high sensitivity, noninvasiveness, and visualization, near-infrared (NIR) fluorescence imaging has been widely studied in biochemistry and biomedicine. As the glutathione (GSH) level in the liver is closely related to the progression of AALI, herein, an NIR fluorescent probe for GSH, HCG was used to dynamically evaluate the effect of DOP on AALI mice. In this study, DOP was proven to maintain the relative balance of GSH content in the liver to protect it from damage. To the best of our knowledge, it is the first time to assess the effect of DOP on AALI mice through a NIR fluorescence imaging technique. This study may also provide a potential NIR imaging agent for the clinical research to improve the management of liver injury-related diseases.


Assuntos
Dendrobium/química , Hepatite Alcoólica/prevenção & controle , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Espectrometria de Fluorescência/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Doença Aguda , Animais , Glutationa/metabolismo , Hepatite Alcoólica/metabolismo , Fígado/metabolismo , Camundongos
6.
Genomics ; 112(2): 1516-1521, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31470081

RESUMO

BACKGROUND: We aimed to better clarify the relationship between FTO/MTHFR/TCF7L2 polymorphisms and PCOS in a larger combined population by performing a meta-analysis. METHODS: Eligible articles were retrieved from Pubmed, Embase, Web of Science and CNKI. Review Manager Version was used to perform statistical analyses. RESULTS: Forty-six studies were included for this meta-analysis. FTO rs9939609 polymorphism was found to be significantly associated with PCOS under dominant, recessive, over-dominant and allele comparisons, MTHFR rs1801131 polymorphism was found to be significantly associated with PCOS under recessive and allele comparisons, and MTHFR rs1801133 polymorphism was also found to be significantly associated with PCOS under dominant, recessive and allele comparisons in general population. In subgroup analyses, we found that positive results were mainly driven by the Asians. CONCLUSIONS: Collectively, this meta-analysis proved that FTO rs9939609, MTHFR rs1801131 and MTHFR rs1801133 polymorphisms may serve as predisposing factors of PCOS, especially for Asians.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Síndrome do Ovário Policístico/genética , Polimorfismo de Nucleotídeo Único , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Feminino , Humanos
7.
Org Biomol Chem ; 18(14): 2646-2649, 2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32207506

RESUMO

The attachment of a dimethylallyl moiety to C4 of 1,3-dihydroxynaphthalene led to spontaneous oxidative cyclisations, resulting in the formation of two tetrahydrobenzofuran and one bicyclo[3.3.1]nonane derivatives. Incubation under an 18O-rich atmosphere proved that both the incorporated oxygen atoms originated from O2. A radical-involved mechanism is proposed for these cyclisations.

8.
J Microencapsul ; 36(4): 356-370, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31190597

RESUMO

Here, we have successfully synthesised and purified multifunctional PLGA-based nanoparticles by the co-encapsulation of an anticancer drug (tetrandrine) and a magnetic material (Fe3O4). The obtained Tet-Fe3O4-PLGA NPs had a uniform spherical shape with a particle size of approximately 199 nm and a negative surface charge of -18.0 mV, displaying a high encapsulation efficiency. Furthermore, TEM studies provided representative images of the purification process of the magnetic nanoparticles with MACS® technology. The MFM and VSM results indicated that both the Fe3O4 NPs and Tet-Fe3O4-PLGA NPs were superparamagnetic. The DSC spectrum demonstrated that Tet was successfully encapsulated within the PLGA-based nanoparticles. Significantly, the release studies revealed NPs had a relatively slower release rate than free Tet after 8 h's initial burst release, which had decreased from 98% to 65% after 24 h. In vitro cellular studies revealed that NPs could effectively penetrate into A549 cells and A549 multicellular spheroids to exert cytotoxicity, displaying a significantly high anti-proliferation effect. Moreover, western blot demonstrated that the co-loaded NPs had a higher anticancer activity by injuring lysosomes to activate the mitochondria pathway and induce A549 cell apoptosis. The magnetic characteristics and high anticancer activity support the use of Tet/Fe3O4 co-loaded PLGA-based nanoparticles as a promising strategy in the treatment of lung cancer.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Benzilisoquinolinas/administração & dosagem , Portadores de Fármacos/química , Nanopartículas de Magnetita/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Células A549 , Antineoplásicos Fitogênicos/farmacocinética , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Benzilisoquinolinas/farmacocinética , Benzilisoquinolinas/farmacologia , Liberação Controlada de Fármacos , Humanos , Neoplasias Pulmonares/tratamento farmacológico
9.
Molecules ; 21(4): 515, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27104499

RESUMO

Hypericum japonicum (Guttiferae), a type of annual or perennial herb, has been historically applied to cure infectious hepatitis, acute and chronic hepatitis, gastrointestinal disorder, and internal hemorrhage. In our successive studies on the genus Hypericum, two new α-pyrones termed japopyrones A and B (1 and 2) were isolated from H. japonicum. Their structures and absolute configurations were established by the comprehensive analyses of spectroscopic data, the application of the Single-crystal X-ray diffraction structural analysis, and the experimental electronic circular dichroism (ECD) spectra. Bioactivity screenings suggested that compound 2 possessed the potential inhibition efficacy on lytic replication of Kaposi's sarcoma associated herpesvirus (KSHV) with an IC50 29.46 µM and a selective index of higher than 6.79, respectively.


Assuntos
Hypericum/química , Lactonas/química , Lactonas/isolamento & purificação , Pironas/química , Pironas/isolamento & purificação , Antivirais/química , Antivirais/isolamento & purificação , Antivirais/farmacologia , Linhagem Celular , Dicroísmo Circular , Herpesvirus Humano 8/efeitos dos fármacos , Humanos , Lactonas/farmacologia , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Pironas/farmacologia , Replicação Viral/efeitos dos fármacos , Difração de Raios X
10.
Molecules ; 21(3): 383, 2016 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-27007360

RESUMO

Zanthoxylum schinifolium Sieb. et Zucc. (Rutaceae), a dioecious shrub with hooked prickly branches, has been used as folk medicine for the treatment of the common cold, stomach ache, diarrhea, and jaundice in China, Korea, and Japan. In our phytochemical investigations on this genus, a new megastigmane sesquiterpenoid, which is referred to as schinifolenol A (1), was isolated from Z. schinifolium. The stereochemistry was characterized via the analyses of extensive spectra. The absolute configuration was established by the application of a modified Mosher's experiment and assisted by a time-dependent density functional theory (TD-DFT) on calculated electronic circular dichroism (ECD). Bioactivity screenings showed that compound 1 exhibited a safe hypotoxicity and a better selectivity on anti-Kaposi's sarcoma associated herpes virus (KSHV).


Assuntos
Cicloexanonas/administração & dosagem , Glucosídeos/administração & dosagem , Herpesvirus Humano 8/efeitos dos fármacos , Norisoprenoides/administração & dosagem , Sarcoma de Kaposi/tratamento farmacológico , Zanthoxylum/química , Dicroísmo Circular , Cicloexanonas/química , Glucosídeos/química , Herpesvirus Humano 8/patogenicidade , Humanos , Estrutura Molecular , Norisoprenoides/química , Compostos Fitoquímicos/administração & dosagem , Compostos Fitoquímicos/química , Extratos Vegetais/química , Sarcoma de Kaposi/virologia
11.
Phytother Res ; 28(12): 1837-45, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25111860

RESUMO

The aim of the study was to evaluate the pro-apoptotic effects of polysaccharides derived from Lentinus edodes and further elucidated the mechanisms of this action. Our results demonstrated that marked morphological changes of apoptosis were observed after treatment of L. edodes polysaccharides [Lentinan (LTN)]. Moreover, LTN-induced cell apoptosis was characterized by a rapid stimulation of reactive oxygen species production, the loss of mitochondrial membrane potential and an increase in intracellular concentration of Ca(2+) . In addition, the results of the haematoxylin and eosin and TUNEL assay further confirmed that LTN-induced apoptosis in vivo. Furthermore, flow cytometry analysis showed that LTN could arrest the cell cycle at G2/M phase, and immunofluorescence showed LTN caused disruption of microtubule. These results suggest that disruption of cellular microtubule network, arrest of the cell cycle at G2/M phase and induction of apoptosis may be one of the possible mechanisms of anti-tumour effect of LTN.


Assuntos
Apoptose/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Lentinano/farmacologia , Microtúbulos/ultraestrutura , Cogumelos Shiitake/química , Animais , Cálcio/metabolismo , Divisão Celular , Linhagem Celular Tumoral , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Espécies Reativas de Oxigênio/metabolismo
12.
Int J Biol Macromol ; 256(Pt 2): 128016, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37967601

RESUMO

Iron deficiency anemia (IDA) is a common micronutrient deficiency among pregnant women with deleterious maternal and fetal outcomes. Angelica sinensis polysaccharide (ASP) has been shown to reduce hepcidin expression in IDA rats. However, the role of ASP in the treatment of IDA during pregnancy and its potential mechanisms have not been investigated. Moreover, the effect of ASP on duodenal iron absorption is not clear. The aim of this study was to investigate the preventive efficacy of ASP against IDA during pregnancy and clarify the underlying mechanisms. Our results showed that ASP improved maternal hematological parameters, increased serum iron, maternal tissue iron, and fetal liver iron content, and improved pregnancy outcomes. Additionally, ASP combated oxidative stress caused by iron deficiency by improving the body's antioxidant capacity. Western blot results demonstrated that ASP downregulated hepcidin expression by blocking the BMP6/SMAD4, JAK2/STAT3 and TfR2/HFE signaling pathways, which in turn increased the expression of FPN1 in the liver, spleen, and duodenum and promoted iron cycling in the body. Furthermore, ASP increased the expression of DMT1 and Dcytb in the duodenum, thereby facilitating duodenal iron uptake. Our results suggest that ASP is a potential agent for the prevention and treatment of IDA during pregnancy.


Assuntos
Angelica sinensis , Hepcidinas , Humanos , Gravidez , Ratos , Feminino , Animais , Hepcidinas/metabolismo , Ferro/metabolismo , Angelica sinensis/metabolismo , Ratos Sprague-Dawley , Polissacarídeos/farmacologia
13.
Org Lett ; 26(2): 536-541, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38179934

RESUMO

In the presence of visible light irradiation, organophoto/nickel dual catalysts, and the mild base K2HPO4, 1,3-enynes react with silanecarboxylic acids to give the corresponding α-silylallenes with high selectivity. In this uniquely decarboxylative hydrosilylation of 1,3-enynes, a silyl radical process is involved and diverse electron-rich and -poor substrates proceed smoothly in moderate to excellent yields. This transformation is particularly synthetically worthwhile when using MeOD as the solvent, which furnishes new access to α-silyldeuteroallenes.

14.
Carbohydr Polym ; 328: 121745, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38220331

RESUMO

Angelica sinensis polysaccharide (ASP) possesses diverse bioactivities; however, its metabolic fate following oral administration remains poorly understood. To intuitively determine its intestinal digestion behavior after oral administration, ASP was labeled with fluorescein, and it was found to accumulate and be degraded in the cecum and colon. Therefore, we investigated the in vitro enzymatic degradation behavior and identified the products. The results showed that ASP could be degraded into fragments with molecular weights similar to those of the fragments observed in vivo. Structural characterization revealed that ASP is a highly branched acid heteropolysaccharide with AG type II domains, and its backbone is predominantly composed of 1,3-Galp, →3,6)-Galp-(1→6)-Galp-(1→, 1,4-Manp, 1,4-Rhap, 1,3-Glcp, 1,2,3,4-Galp, 1,3,4,6-Galp, 1,3,4-GalAp and 1,4-GlcAp, with branches of Araf, Glcp and Galp. In addition, the high molecular weight enzymatic degradation products (ASP H) maintained a backbone structure almost identical to that of ASP, but exhibited only partial branch changes. Then, the results of ethanol-induced acute liver injury experiments revealed that ASP and ASP H reduced the expression of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), and malondialdehyde (MDA) and increased the superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) levels, thereby relieving ethanol-induced acute liver injury.


Assuntos
Angelica sinensis , Angelica sinensis/química , Etanol/toxicidade , Etanol/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Fígado , Estresse Oxidativo
15.
PLoS One ; 19(2): e0298329, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38412183

RESUMO

Monitoring the temperature to determine the fire source locations is essential for controlling the spontaneous combustion in the goaf. Optical fiber sensors are employed to measure the temperature distribution in the goaf. However, due to changes in the geological conditions and the influence of the falling rocks in the goaf, only sensors on the upper side of the uncompacted goaf, due to inclination and coal pillar, may remain. Unilateral sensors are located on the upper side of the goaf, while fire occurs in the center. To investigate the issue with linear unilateral sensors, a two-dimensional inverse method has been developed to determine the location of fire sources by considering heat transfer after a fire inside the goaf. The equations were theoretically solved using Green's function method to obtain the internal temperature distribution of the physical model of the goaf. Sensitivity analysis identified the most crucial parameters in the process of spontaneous heating at different temperature. The fire source location can be determined using a loop method based on the model calculations. We considered a case to validate the model. Accurately identifying the fire source location in the goaf using the unilateral sensors has an essential theoretical and practical significance for fire prevention and fighting.


Assuntos
Minas de Carvão , Incêndios , Fibras Ópticas , Minas de Carvão/métodos , Combustão Espontânea , Carvão Mineral
16.
Carbohydr Polym ; 333: 121974, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38494227

RESUMO

Astragalus membranaceus polysaccharide (APS) possesses excellent immunomodulatory activity. However, there are several studies on the structural characterization of APS. Here, we aimed to elucidate the repeating units of polysaccharides (APS1, 106.5 kDa; APS2, 114.5 kDa) obtained from different Astragalus membranaceus origins and further investigated their immunomodulatory activities. Based on structural analysis, types of the two polysaccharides were identified as arabinogalactan-I (AG-I) and arabinogalactan-II (AG-II), and co-elution of arabinogalactans (AGs) and α-glucan was observed. The backbone of AG-I was 1,4-linked ß-Galp occasionally substituted by α-Araf at O-2 and/or O-3. AG-II was a highly branched polysaccharide with long branches of α-Araf, which were attached to the O-3 of 1,6-linked ß-Galp of the backbone. The presence of AGs in A. membranaceus was confirmed for the first time. The two polysaccharides could promote the expression of IL-6, IL-1ß and TNF-α in RAW264.7 cells via MAPKs and NF-κB signaling pathways. The constants for APS1 and APS2 binding to Toll-like receptor 4 (TLR4) were 1.83 × 10-5 and 2.08 × 10-6, respectively. Notably, APS2 showed better immunomodulatory activity than APS1, possibly because APS2 contained more AGs. Hence, the results suggested that AGs were the vital components of APS in the immunomodulatory effect.


Assuntos
Astragalus propinquus , Galactanos , Galactanos/farmacologia , Galactanos/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Transdução de Sinais
17.
Carbohydr Polym ; 339: 122256, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823922

RESUMO

Recently, the intestinal lymphatic transport based on Peyer's patches (PPs) is emerging as a promising absorption pathway for natural polysaccharides. Herein, the aim of this study is to investigate the PP-based oral absorption of a pectic polysaccharide from Smilax china L. (SCLP), as well as its uptake and transport mechanisms in related immune cells. Taking advantages of the traceability of fluorescently labeled SCLP, we confirmed that SCLP could be absorbed into PPs and captured by their mononuclear phagocytes (dendritic cells and macrophages) following oral administration. Subsequently, the systematic in vitro study suggested that the endocytic mechanisms of SCLP by model mononuclear phagocytes (BMDCs and RAW264.7 cells) mainly involved caveolae-mediated endocytosis, macropinocytosis and phagocytosis. More importantly, SCLP directly binds and interacts with toll-like receptor 2 (TLR2) and galectin 3 (Gal-3) receptor, and was taken up by mononuclear phagocytes in receptor-mediated manner. After internalization, SCLP was intracellularly transported primarily through endolysosomal pathway and ultimately localized in lysosomes. In summary, this work reveals novel information and perspectives about the in vivo fate of SCLP, which will contribute to further research and utilization of SCLP and other pectic polysaccharides.


Assuntos
Nódulos Linfáticos Agregados , Smilax , Animais , Camundongos , Células RAW 264.7 , Nódulos Linfáticos Agregados/metabolismo , Smilax/química , Endocitose , Pectinas/química , Pectinas/metabolismo , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Fagócitos/metabolismo , Fagócitos/efeitos dos fármacos , Receptor 2 Toll-Like/metabolismo , Camundongos Endogâmicos BALB C , Masculino , Células Dendríticas/metabolismo , Células Dendríticas/efeitos dos fármacos , Administração Oral
18.
Nat Prod Res ; 37(16): 2697-2703, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36214541

RESUMO

Dendrobium catenatum Lindl. has been long used in China as a functional food and traditional Chinese medicine and polysaccharides from Dendrobium catenatum Lindl. (DOP) exhibited extensive bioactivities. However, studies on the structure-activity relationship of DOP are rarely reported. Here, two polysaccharides named DOP-1 and DOP-2 were obtained, which differed in the ratio of monosaccharide composition and molecular weight. Structural characteristics were elucidated by spectral and chemical analysis. The main structures of DOPs were the linkage of ß-(1→4)-D-Manp, with some attached 2-O- or 3-O-acetylated groups. Additionally, the DPPH, hydroxyl and superoxide radicals scavenging assays of DOP-1 and DOP-2 showed that DOP-2 exhibited the higher antioxidant activity, which might be related to its lower molecular weight, higher mannose proportion and lower degree of acetylation, and higher phenolic content. Our results provide a more accurate basis for the application of DOPs in the pharmaceutical and food industries.

19.
Int J Biol Macromol ; 253(Pt 6): 127126, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37778573

RESUMO

In this study, a porous sponge material was formed by physically mixing chitosan (CS) and Angelica sinensis polysaccharide (ASP). After removing the water by freeze-drying, the CS/ASP sponge was obtained. The prepared sponges exhibited excellent swelling properties, thermal stability and biocompatibility as well as improvements over the insufficient mechanical properties of pure chitosan sponges. Notably, the ASP released from the CS/ASP sponge could be effectively absorbed by the liver, which endowed the CS/ASP sponge with effective liver-protective effects against CCl4-induced acute liver injury; these protective effects surpassed those of both blank CS and CS/Dextran sponges. The underlying protective mechanism may involve the activation of the Nrf2-mediated antioxidant signaling pathway and the inhibition of hepatocyte apoptosis. Understanding CS/ASP sponges may provide new insights and inspire new methods for the clinical application of ASP. At the same time, we hope to suggest future directions for the development of polysaccharide preparations.


Assuntos
Angelica sinensis , Quitosana , Quitosana/farmacologia , Polissacarídeos/farmacologia , Fígado , Antioxidantes/farmacologia
20.
Int J Biol Macromol ; 242(Pt 1): 124707, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37146861

RESUMO

As typical acetylated glucomannans, Dendrobium officinale polysaccharides (DOPs) from different origins differ in their structural characteristics and some of their physicochemical properties. To rapidly select D. officinale plants, we systematically investigate the differences among DOPs from different origins and analyzed the structural characteristics, such as the degree of acetylation and monosaccharide composition; the physicochemical properties, such as solubility, water absorption and apparent viscosity; and the lipid-lowering activity of the obtained DOPs. Principal component analysis (PCA), a method for analyzing multiple variables, was used to analyze the relationship between the physicochemical and structural properties, and lipid-lowering activity. It was found that the structural and physicochemical characteristics had significant effects on lipid-lowering activity, and DOPs with a high degree of acetylation, high apparent viscosity and large D-mannose-to-d-glucose ratio were associated with greater lipid-lowering activity. Therefore, this study provides a reference for the selection and application of D. officinale.


Assuntos
Dendrobium , Dendrobium/química , Análise de Componente Principal , Monossacarídeos , Polissacarídeos/química , Lipídeos
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