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1.
Int J Clin Oncol ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080116

RESUMO

OBJECTIVE: To verify whether severe weight loss is a reasonable risk sign for the effect of PD-1 treatment in advanced gastric cancer (GC) patients. METHODS: 127 metastatic or recurrent GC patients treated with PD-1 inhibitors in Xuzhou Central Hospital were involved in this study. Two cohorts with different variables were built; one was used to reveal the relationship between body weight loss and overall survival (OS), and the other was used to find which body composition contributed to the weight loss. Variables were collected at PD-1 inhibitor initiation (baseline) and week 6 of treatment. Patients were followed up from the end of therapy to November 2022. Overall survival (OS) and disease-free survival (DFS) were recorded. RESULTS: 127 patients with metastatic/recurrent gastric cancer received PD-1 treatment, among whom 117 had complete weight data. After screening, data from 69 patients were used for body composition assessment. The study found that 33 patients who lost more than 2% of their body weight within six weeks had poorer OS and DFS, with medians of 9.5 months and 6 months, respectively. Cox regression analysis showed that weight loss of more than 2% and treatment methods was an independent risk for poor OS and DFS. Further analysis revealed that weight loss was mainly caused by a reduction in adipose tissue, rather than muscle mass. CONCLUSION: Severe weight loss is a potential monitor for the treatment effect of PD-1 inhibitor in advanced GC patients.

2.
J Clin Lab Anal ; 38(7): e25031, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38514901

RESUMO

BACKGROUND: Primary cilia are static microtubule-based structures protruding from the cell surface and present on most vertebrate cells. The appropriate localization of phospholipids is essential for cilia formation and stability. INPP5E is a cilia-localized inositol 5-phosphatase; its deletion alters the phosphoinositide composition in the ciliary membrane, disrupting ciliary function. METHODS: The EGFP-2xP4MSidM, PHPLCδ1-EGFP, and SMO-tRFP plasmids were constructed by the Gateway system to establish a stable RPE1 cell line. The INPP5E KO RPE1 cell line was constructed with the CRISPR/Cas9 system. The localization of INPP5E and the distribution of PI(4,5)P2 and PI4P were examined by immunofluorescence microscopy. The fluorescence intensity co-localized with cilia was quantified by ImageJ. RESULTS: In RPE1 cells, PI4P is localized at the ciliary membrane, whereas PI(4,5)P2 is localized at the base of cilia. Knocking down or knocking out INPP5E alters this distribution, resulting in the distribution of PI(4,5)P2 along the ciliary membrane and the disappearance of PI4P from the cilia. Meanwhile, PI(4,5)P2 is located in the ciliary membrane labeled by SMO-tRFP. CONCLUSIONS: INPP5E regulates the distribution of phosphoinositide on cilia. PI(4,5)P2 localizes at the ciliary membrane labeled with SMO-tRFP, indicating that ciliary pocket membrane contains PI(4,5)P2, and phosphoinositide composition in early membrane structures may differ from that in mature ciliary membrane.


Assuntos
Cílios , Monoéster Fosfórico Hidrolases , Cílios/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Monoéster Fosfórico Hidrolases/genética , Humanos , Linhagem Celular , Fosfatidilinositol 4,5-Difosfato/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/citologia , Fosfatos de Fosfatidilinositol/metabolismo , Sistemas CRISPR-Cas , Fosfolipídeos/metabolismo
3.
J Clin Lab Anal ; 38(7): e25030, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38525916

RESUMO

BACKGROUND: The motor protein dynein is integral to retrograde transport along microtubules and interacts with numerous cargoes through the recruitment of cargo-specific adaptor proteins. This interaction is mediated by dynein light intermediate chain subunits LIC1 (DYNC1LI1) and LIC2 (DYNC1LI2), which govern the adaptor binding and are present in distinct dynein complexes with overlapping and unique functions. METHODS: Using bioinformatics, we analyzed the C-terminal domains (CTDs) of LIC1 and LIC2, revealing similar structural features but diverse post-translational modifications (PTMs). The methylation status of LIC2 and the proteins involved in this modification were examined through immunoprecipitation and immunoblotting analyses. The specific methylation sites on LIC2 were identified through a site-directed mutagenesis analysis, contributing to a deeper understanding of the regulatory mechanisms of the dynein complex. RESULTS: We found that LIC2 is specifically methylated at the arginine 397 residue, a reaction that is catalyzed by protein arginine methyltransferase 1 (PRMT1). CONCLUSIONS: The distinct PTMs of the LIC subunits offer a versatile mechanism for dynein to transport diverse cargoes efficiently. Understanding how these PTMs influence the functions of LIC2, and how they differ from LIC1, is crucial for elucidating the role of dynein-related transport pathways in a range of diseases. The discovery of the arginine 397 methylation site on LIC2 enhances our insight into the regulatory PTMs of dynein functions.


Assuntos
Arginina , Dineínas do Citoplasma , Proteína-Arginina N-Metiltransferases , Proteínas Repressoras , Metilação , Arginina/metabolismo , Arginina/química , Humanos , Dineínas do Citoplasma/metabolismo , Dineínas do Citoplasma/genética , Dineínas do Citoplasma/química , Proteína-Arginina N-Metiltransferases/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Processamento de Proteína Pós-Traducional , Dineínas/metabolismo , Dineínas/genética , Dineínas/química , Sequência de Aminoácidos
4.
Mikrochim Acta ; 191(5): 272, 2024 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634999

RESUMO

A biosensing electrochemical platform for heat shock protein 70 (HSP70) has been developed by integrating a three-electrode indium tin oxide (ITO) on a chip. The platform includes modifications to the reference electrode and working electrode for the detection of HSP70. The new platform is constructed by assembly of HSP70 antibody on PS-AuNPs@Cys/Au indium tin oxide (ITO) electrode to create a high HSP70 sensitive surface. The PS-AuNPs@Cys/Au indium tin oxide (ITO) electrode is obtained by immersing the ITO electrode into the PS-AuNPs@Cys solution and performing constant potential deposition at -1.4 V (Ag/AgCl). The PS-AuNPs@Cys/Au film deposited on ITO glass provides a desirable substrate for the immobilization of the HSP70 antibody and improves the loading of antibody between PS-AuNPs@Cys/Au and the electrode resulting in a significant amplification. Under optimal conditions, the fabricated sensor demonstrates a linear range extending from 0.1 ng mL- 1 to 1000 ng mL- 1, with an impressive detection limit of 25.7 pg mL- 1 (S/N = 3). The developed immunoassay method successfully detected the HSP70 content in normal human blood samples and outperformed the ELISA method commonly used for clinical sample analysis.


Assuntos
Ouro , Nanopartículas Metálicas , Compostos de Estanho , Humanos , Anticorpos , Proteínas de Choque Térmico HSP70
5.
Exp Cell Res ; 384(2): 111642, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31562862

RESUMO

Our hypothesis is that hyaluronic acid may regulate the differentiation of human amniotic epithelial cells (hAECs) into insulin-producing cells and help the treatment of type 1 diabetes. Herein, a protocol for the stepwise in vitro differentiation of hAECs into functional insulin-producing cells was developed by mimicking the process of pancreas development. Treatment of hAECs with hyaluronic acid enhanced their differentiation of definitive endoderm and pancreatic progenitors. Endodermal markers Sox17 and Foxa2 and pancreatic progenitor markers Pax6, Nkx6.1, and Ngn3 were upregulated an enhanced gene expression in hAECs, but hAECs did not express the ß cell-specific transcription factor Pdx1. Interestingly, hyaluronic acid promoted the expression of major pancreatic development-related genes and proteins after combining with commonly used inducers of stem cells differentiation into insulin-producing cells. This indicated the potent synergistic effects of the combination on hAECs differentiation in vitro. By establishing a multiple injection transplantation strategy via tail vein injections, hAECs transplantation significantly reduced hyperglycemia symptoms, increased the plasma insulin content, and partially repaired the islet structure in type 1 diabetic mice. In particular, the combination of hAECs with hyaluronic acid exhibited a remarkable therapeutic effect compared to both the insulin group and the hAECs alone group. The hAECs' paracrine action and hyaluronic acid co-regulated the local immune response, improved the inflammatory microenvironment in the damaged pancreas of type 1 diabetic mice, and promoted the trans-differentiation of pancreatic α cells into ß cells. These findings suggest that hyaluronic acid is an efficient co-inducer of the differentiation of hAECs into functional insulin-producing cells, and hAECs treatment with hyaluronic acid may be a promising cell-replacement therapeutic approach for the treatment of type 1 diabetes.


Assuntos
Âmnio/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/terapia , Células Epiteliais/efeitos dos fármacos , Ácido Hialurônico/farmacologia , Ativinas/metabolismo , Âmnio/metabolismo , Animais , Técnicas de Cultura de Células/métodos , Terapia Baseada em Transplante de Células e Tecidos/métodos , Células Cultivadas , Modelos Animais de Doenças , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Endoderma/efeitos dos fármacos , Endoderma/metabolismo , Células Epiteliais/metabolismo , Humanos , Inflamação/metabolismo , Insulina/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Masculino , Camundongos , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo
6.
BMC Complement Altern Med ; 19(1): 230, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31443712

RESUMO

BACKGROUND: Hyperglycemia and dyslipidemia are classic features of patients with diabetes mellitus (DM). Cordyceps taii, a folk medicinal fungus native to southern China, possesses various pharmacological activities. This study aimed to assess the glucose-lowering and hypolipidemic effects of polysaccharides from C. taii (CTP) in streptozotocin (STZ)-induced diabetic mice. METHODS: Kunming mice were intraperitoneally injected with STZ at a dose of 100 mg/kg body weight. After induction of diabetes, diabetic mice were randomly divided into five groups: diabetic mellitus group (DM), metformin-treated group, low, medium, and high-dose CTP-treated group (CTP-L, CTP-M, and CTP-H). Normal mice served as the control group. After treatment for 28 days, body weight, fasting serum insulin (FSI), fasting blood glucose (FBG), homeostasis model assessment-insulin resistance (HOMA-IR), triglyceride (TG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and C-reactive protein (CRP) levels were measured. Histological analysis of pancreatic tissue and immune organ indices was also performed to evaluate the anti-diabetes effect of CTP. SPSS (version 21.0) software was used for statistical analysis, and statistical differences were considered significant at p < 0.05. RESULTS: Compared with the DM group, the body weight and FSI level of CTP-H group increased by 36.13 and 32.47%, whereas the FBG and HOMA-IR decreased by 56.79 and 42.78%, respectively (p < 0.05). Histopathological examination of the pancreas revealed that CTP improved and repaired the impaired islet ß-cells in pancreatic tissue. Compared with the DM group, the levels of TC, TG, and LDL-C decreased by 13.84, 31.87, and 36.61%, whereas that of HDL-C increased by 28.60% in CTP-H (p < 0.05). Further study showed that the thymus index in CTP-H was elevated by approximately 54.96%, and the secretion of pro-inflammatory cytokines TNF-α, IL-6, and CRP was inhibited by approximately 19.97, 34.46, and 35.41%, respectively (p < 0.05). CONCLUSION: The anti-diabetes effect of CTP is closely associated with immunoregulation and anti-inflammation, and CTP may be considered as a therapeutic drug or functional food for DM intervention.


Assuntos
Cordyceps/química , Diabetes Mellitus Experimental/metabolismo , Polissacarídeos Fúngicos/farmacologia , Hipoglicemiantes/farmacologia , Hipolipemiantes/farmacologia , Animais , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Polissacarídeos Fúngicos/química , Hipoglicemiantes/química , Hipolipemiantes/química , Masculino , Medicina Tradicional Chinesa , Camundongos , Estreptozocina
7.
Reprod Domest Anim ; 54(11): 1443-1448, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31381183

RESUMO

To improve the efficiency of somatic cell nuclear transfer (SCNT) in sheep, we investigated the effects of recipient oocyte source, number of transferred embryos and season on the pregnancy and live lamb rates for sheep somatic cell nuclear transfer embryos. Follicle-stimulating hormone (FSH)-stimulated ovaries produced significantly more oocytes both in total and of suitable quality for maturation culture than those without FSH treatment (from slaughterhouse). However, their in vitro maturation rates were similar. Embryos were reconstructed using adult fibroblast cells into enucleated MII oocytes. The pregnancy and term rates were significantly higher in the FSH-stimulated group than in the slaughterhouse one. Oocytes from FSH-stimulated ovaries were enucleated as recipient cytoplasm for nuclear transfer in the following experiments. The transfer of 7-9 and 11-13 embryos produced significantly higher pregnancy rates than that of six embryos. However, the former groups exhibited similar live lamb rates. FSH-stimulated ovaries produced significantly more oocytes in November and December (winter) than in May to July (summer), but the associated maturation rate did not increase. Pregnancy and term rates were significantly higher when transfer occurred in winter than in summer. In conclusion, FSH treatment produced significant benefit regarding the number and quality of collected oocytes and also for the pregnancy and live lamb rates for reconstructed embryos. However, the transfer of an appropriate number of embryos (7-13) and at an appropriate season (winter) increased pregnancy and term rates.


Assuntos
Transferência Embrionária/veterinária , Técnicas de Transferência Nuclear/veterinária , Estações do Ano , Carneiro Doméstico/fisiologia , Animais , Feminino , Hormônio Foliculoestimulante/farmacologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos , Ovário/efeitos dos fármacos , Gravidez , Taxa de Gravidez
8.
Zhongguo Zhong Yao Za Zhi ; 44(5): 905-911, 2019 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-30989848

RESUMO

Ganoderic acid(GA) is one of main bioactive components produced by Ganoderma lucidum,which a traditional Chinese herbal medicine and a kind of tracyclic triterpene lanosterol derivatives with highly oxidized structure. It has a variety of important pharmacological activities,such as anticancer,immunoregulation,anti-oxidation,anti-diabetes and anti-HIV. At present,the studies of GA mainly focus on biosynthesis,fermentation control,isolation and purification,structure identification and pharmacological effects.However,there are a fewer pharmacokinetic studies of GA,although it is closely related to the clinical application. Recent studies have shown that GA can be absorbed rapidly by gastrointestinal tract and distributed in various tissues and organs after oral intake. GA is metabolized by liver at phase Ⅰ and phase Ⅱ,and then mainly excreted by bile. In this paper,the pharmacokinetic characteristics of GA and its absorption,distribution,metabolism and excretion(ADME) will be systematically summarized,in order to provide scientific basis for the application and development studies of Ganoderma triterpenoid drugs and their rational clinical use.


Assuntos
Reishi/química , Triterpenos/farmacocinética , Humanos , Lanosterol/farmacocinética
9.
Cell Biol Int ; 42(10): 1401-1409, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29993158

RESUMO

We investigated the dynamic changes in chromatin and microtubules at the first cell cycle in goat somatic cell nuclear transfer (SCNT)-derived and in vitro fertilization (IVF)-derived embryos. Stage-dependent and characteristic changes to chromatin and microtubules occurred in SCNT-derived embryos at different times after activation. About half donor nuclei underwent premature chromosome condensation (PCC) at 1 h post activation, and furtherly reached telophase at 2 h after activation. However, we discovered that the separated chromosomes reaggregated, not keeping two independent nuclei; and formed one pronucleus at 2.5 h after activation. One pronucleus was found in all reconstructed oocytes except other no nucleus oocytes from 3 to 22 h after activation. Reconstructed oocytes reached the first mitotic metaphase at 23 h post activation, which was later than that of IVF-derived embryos at 16 h after insemination. SCNT-derived embryos showed significantly higher abnormalities in the first mitotic metaphase spindle, compared with IVF-derived embryos. Abnormal spindles included multi polar and half spindles. SCNT-derived embryos began to cleave at 24 h after activation, which was later than that of IVF-derived embryos at 21 h after insemination. SCNT-derived embryos showed delayed conversion from telophase to interphase than IVF-derived embryos during cleavage. These might lead to poor development in SCNT-derived embryos.


Assuntos
Cromatina/metabolismo , Microtúbulos/metabolismo , Animais , Ciclo Celular/fisiologia , Núcleo Celular/metabolismo , China , Cromatina/fisiologia , Cromossomos/metabolismo , Clonagem de Organismos/métodos , Embrião de Mamíferos/citologia , Desenvolvimento Embrionário/fisiologia , Feminino , Fertilização in vitro/métodos , Fertilização in vitro/veterinária , Células Germinativas , Cabras/metabolismo , Metáfase/fisiologia , Microtúbulos/fisiologia , Mitose/fisiologia , Técnicas de Transferência Nuclear/veterinária , Oócitos/citologia , Fuso Acromático/metabolismo
10.
Exp Cell Res ; 345(2): 218-29, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27237096

RESUMO

This study investigated the pro-proliferative effect of hyaluronic acid (HA) on human amniotic mesenchymal stem cells (hAMSCs) and the underlying mechanisms. Treatment with HA increased cell population growth in a dose- and time-dependent manner. Analyses by flow cytometry and immunocytochemistry revealed that HA did not change the cytophenotypes of hAMSCs. Additionally, the osteogenic, chondrogenic, and adipogenic differentiation capabilities of these hAMSCs were retained after HA treatment. Moreover, HA increased the mRNA expressions of wnt1, wnt3a, wnt8a, cyclin D1, Ki-67, and ß-catenin as well as the protein level of ß-catenin and cyclin D1 in hAMSCs; and the nuclear localization of ß-catenin was also enhanced. Furthermore, the pro-proliferative effect of HA and up-regulated expression of Wnt/ß-catenin pathway-associated proteins - wnt3a, ß-catenin and cyclin D1 in hAMSCs were significantly inhibited upon pre-treatment with Wnt-C59, an inhibitor of the Wnt/ß-catenin pathway. These results suggest that HA may positively regulate hAMSCs proliferation through regulation of the Wnt/ß-catenin signaling pathway.


Assuntos
Âmnio/citologia , Ácido Hialurônico/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , Benzenoacetamidas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Ciclina D1/metabolismo , Feminino , Imunofluorescência , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Fenótipo , Gravidez , Proteínas Proto-Oncogênicas c-myc/metabolismo , Piridinas/farmacologia , Via de Sinalização Wnt/genética , beta Catenina/metabolismo
11.
Bioorg Med Chem Lett ; 25(9): 1823-6, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25863432

RESUMO

Three new cytochalasins (1-3) together with two known cytochalasin analogues (4 and 5) were isolated from the chloroform fraction of ethanolic extract of a medicinal macrofungus Cordyceps taii. The structures of the new compounds were elucidated on the basis of spectroscopic analysis, including HRESIMS, 1D and 2D NMR experiments. The cytotoxicities of Compounds 1-5 were investigated by the sulforhodamine B (SRB) method in vitro against human highly metastatic lung cancer cell 95-D, human lung cancer cell line A-549 and normal hepatocyte HL-7702. The results revealed that Compounds 4 and 5 showed potent antitumor activities against human lung cancer cell 95-D with IC50 value of 3.67 and 4.04 µM, respectively. In comparison with cisplatin, the first-line chemotherapy drug, they had little or no cytotoxicity on normal cells, but showed stronger cytotoxic effects on cancer cells 95-D.


Assuntos
Antineoplásicos/farmacologia , Cordyceps/química , Citocalasinas/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Citocalasinas/química , Citocalasinas/isolamento & purificação , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
12.
BMC Complement Altern Med ; 15: 216, 2015 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-26155792

RESUMO

BACKGROUND: Cordyceps taii, an entomogenous fungus native to south China, is a folk medicine with varieties of pharmacological activities including anticancer effect. To validate the ethnopharmacological claim against cancer, the antitumor and antimetastatic activities of chloroform extract of C. taii (CFCT) were investigated in vivo. METHODS: The in vitro cytotoxic activities of CFCT against human lung cancer (A549) and gastric cancer (SGC-7901) cells were evaluated using the Sulforhodamine B (SRB) assay. In vivo anti tumor and antimetastatic activities, Kunming mice bearing sarcoma 180 and C57BL/6 mice bearing melanoma B16F10 were employed, respectively. The antitumor effects of CFCT were completely evaluated on the basis of the tumor weight, survival time, histologic analysis, and immune organ indices. The histopathological change, metastatic foci and malignant melanoma specific marker HMB45 in the lung tissue were detected for the evaluation of the antimetastatic activity of CFCT. RESULTS: CFCT exhibited dose- and time-dependent cytotoxicities against A549 and SGC-7901 cells with the IC50 values of 30.2 and 65.7 µg/mL, respectively. Furthermore, CFCT at a dose of 50 or 100 mg/kg could significantly inhibit the tumor growth in vivo and prolonged the survival time in two different models as compared with the model group, especially when combined with the CTX at a low dose rate. And it also increased spleen index of Kunming mice and thymus index of C57BL/6 mice. Meanwhile, histologic analysis illustrated that CFCT alone or in combination with CTX could induce tumor tissue necrosis of both models. In addition, CFCT at a dose of 50 or 100 mg/kg inhibited the lung metastasis of melanoma B16F10 in tumor-bearing C57BL/6 mice. The antimetastatic effect was also observed when CFCT was used in combination with CTX. In comparison to any other groups, CFCT at a dose of 100 mg/kg could effectively enhance the GSH-Px activities of various tissues in tumor-bearing C57BL/6 mice. CONCLUSIONS: These findings demonstrate that CFCT has potent in vivo antitumor and antimetastatic activities, and may be helpful to the development of anticancer chemopreventive agents from C. taii.


Assuntos
Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Cordyceps/química , Animais , Antineoplásicos/química , Produtos Biológicos/química , Linhagem Celular Tumoral , Humanos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos C57BL , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Zhongguo Zhong Yao Za Zhi ; 40(2): 174-9, 2015 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-26080540

RESUMO

Due to substantial morbidity and high complications, diabetes mellitus is considered as the third "killer" in the world. Medicinal fungal polysaccharides, as water-soluble macromolecular substances with low toxicity, exhibit diversified pharmacological actions such as immune regulation, anti-tumor, antivirus, antioxidant, anti-aging, hypoglycemic effect and improving liver and kidney function. In recent year, a number of investigators reported medicinal fungal polysaccharides showed good anti-diabetes and hypoglycemic activity, and their acting mechanisms involved in glycometabolism and ß cell function, e. g. promoting glycogen synthesis, promoting glycolysis, inhibiting the activity of α-glucosidase, promoting insulin secretion, increasing insulin sensitivity, enhancing antioxidation. Therefore, the hypoglycemic activity and its mechanisms of action of medicinal fungal polysaccharides showed characteristics of multiple effects, multi-target, and multi-pathway regulation. These finding suggest that medicinal fungal polysaccharides are a promising source for the development of discovery of anti-diabetic agent.


Assuntos
Polissacarídeos Fúngicos/farmacologia , Hipoglicemiantes/farmacologia , Animais , Metabolismo dos Carboidratos/efeitos dos fármacos , Humanos , Resistência à Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos
14.
Adv Sci (Weinh) ; 11(17): e2309271, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38368258

RESUMO

Well-defined nanostructures are crucial for precisely understanding nano-bio interactions. However, nanoparticles (NPs) fabricated through conventional synthesis approaches often lack poor controllability and reproducibility. Herein, a synthetic biology-based strategy is introduced to fabricate uniformly reproducible protein-based NPs, achieving precise control over heterogeneous components of the NPs. Specifically, a ferritin assembly toolbox system is developed that enables intracellular assembly of ferritin subunits/variants in Escherichia coli. Using this strategy, a proof-of-concept study is provided to explore the interplay between ligand density of NPs and their tumor targets/penetration. Various ferritin hybrid nanocages (FHn) containing human ferritin heavy chains (FH) and light chains are accurately assembled, leveraging their intrinsic binding with tumor cells and prolonged circulation time in blood, respectively. Further studies reveal that tumor cell uptake is FH density-dependent through active binding with transferrin receptor 1, whereas in vivo tumor accumulation and tissue penetration are found to be correlated to heterogeneous assembly of FHn and vascular permeability of tumors. Densities of 3.7 FH/100 nm2 on the nanoparticle surface exhibit the highest degree of tumor accumulation and penetration, particularly in tumors with high permeability compared to those with low permeability. This study underscores the significance of nanoparticle heterogeneity in determining particle fate in biological systems.


Assuntos
Ferritinas , Nanopartículas , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Modelos Animais de Doenças , Ferritinas/metabolismo , Ferritinas/química , Nanopartículas/química , Nanopartículas/metabolismo , Nanoestruturas/química , Neoplasias/metabolismo , Feminino , Camundongos Endogâmicos BALB C
15.
Nat Commun ; 15(1): 2488, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509071

RESUMO

Homotypic membrane fusion of the endoplasmic reticulum (ER) is mediated by dynamin-like GTPase atlastin (ATL). This fundamental process relies on GTP-dependent domain rearrangements in the N-terminal region of ATL (ATLcyto), including the GTPase domain and three-helix bundle (3HB). However, its conformational dynamics during the GTPase cycle remain elusive. Here, we combine single-molecule FRET imaging and molecular dynamics simulations to address this conundrum. Different from the prevailing model, ATLcyto can form a loose crossover dimer upon GTP binding, which is tightened by GTP hydrolysis for membrane fusion. Furthermore, the α-helical motif between the 3HB and transmembrane domain, which is embedded in the surface of the lipid bilayer and self-associates in the crossover dimer, is required for ATL function. To recycle the proteins, Pi release, which disassembles the dimer, activates frequent relative movements between the GTPase domain and 3HB, and subsequent GDP dissociation alters the conformational preference of the ATLcyto monomer for entering the next reaction cycle. Finally, we found that two disease-causing mutations affect human ATL1 activity by destabilizing GTP binding-induced loose crossover dimer formation and the membrane-embedded helix, respectively. These results provide insights into ATL-mediated homotypic membrane fusion and the pathological mechanisms of related disease.


Assuntos
Proteínas de Drosophila , Humanos , Proteínas de Drosophila/metabolismo , Fusão de Membrana/fisiologia , GTP Fosfo-Hidrolases/metabolismo , Hidrólise , Guanosina Trifosfato/metabolismo
16.
Zhonghua Nei Ke Za Zhi ; 52(5): 407-11, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-23945308

RESUMO

OBJECTIVE: To explore the potential mechanism of the inhibition of increased intracellular free calcium concentration ([Ca²âº]i) by short-term exposure to the islet amyloid polypeptide (IAPP) in high glucose-stimulated pancreatic ß cells. METHODS: The pancreatic ß cells were loaded with calcium sensitive fluorescent indicator Fluo-4/AM. The fluorescence intensity, which represented [Ca²âº]i, was measured in time by laser scanning confocal microscope before and after stimulated by glucose, KCl, caffeine and carbachol. RESULT: The fluorescence intensity F/F0 in INS-1 cells, increased to about 2 folds after glucose stimulation. After the exposure to the IAPP with different concentration, the fluorescence intensity F/F0 was decreased slightly in the pretreated cells by 16.7 mmol/L glucose with 0.5 µmol/L IAPP. However, after the pretreatment of IAPP with the concentration of 1.0, 5.0, 10.0 µmol/L, the fluorescence intensity F/F0 showed a dose-dependent decrease with statistical difference. The fluorescence intensity F/F0 in the cells increased rapidly in a peak pattern after the stimulation of 30 mmol/L KCl. But with the pretreatment of 10.0 µmol/L IAPP, the fluorescence intensity F/F0 decreased with statistical difference. With 20 mmol/L caffeine and 100 µmol/L carbachol which stimulated Ca²âº release respectively from internal ryanodine receptor (RYR) and inositol triphosphate (IP3) Ca²âº storage, the fluorescence intensity F/F0 curve presented a peak pattern. After 10 µmol/L IAPP pretreatment, the fluorescence intensity F/F0 showed no statistical difference from the control group. CONCLUSIONS: The short-term effect of IAPP on pancreatic ß cells has no influence on the caffeine and carbachol stimulated Ca²âº release from endoplasmic reticulum RYR and IP3 Ca²âº storage. The inhibition of calcium increase in INS-1 cells by short-term exposure to IAPP may mainly via inhibiting the voltage-gated L-calcium channels with intact release capacity of Ca²âº storage.


Assuntos
Cálcio/metabolismo , Glucose/farmacologia , Células Secretoras de Insulina/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas/farmacologia , Linhagem Celular , Humanos
17.
Environ Sci Pollut Res Int ; 30(27): 69913-69926, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37140865

RESUMO

Chronic exposure to excessive environmental fluoride has caused fluorosis to become a major public health problem worldwide. Although studies on stress pathways, signaling pathways, and apoptosis induced by fluoride have provided an in-depth understanding of the mechanism of this disease, its exact pathogenesis remains unclear. We hypothesized that the human gut microbiota and metabolome are associated with the pathogenesis of this disease. To get further insight into the profiles of intestinal microbiota and metabolome in coal-burning-induced endemic fluorosis patients, we conducted 16S rRNA sequencing of the intestinal microbial DNA and carried out non-targeted metabolomics of fecal samples from 32 patients with skeletal fluorosis and 33 matched healthy controls in Guizhou, China. We found that the gut microbiota of coal-burning endemic fluorosis patients displayed significant differences in composition, diversity, and abundance compared with healthy controls. This was characterized by an increase in the relative abundance of Verrucomicrobiota, Desulfobacterota, Nitrospirota, Crenarchaeota, Chloroflexi, Myxococcota, Acidobacteriota, Proteobacteria, and unidentified_Bacteria, and a significant decrease in the relative abundance of Firmicutes and Bacteroidetes at the phylum level. Additionally, at the genus level, the relative abundance of some beneficial bacteria, such as Bacteroides, Megamonas, Bifidobacterium, and Faecalibacterium, was significantly reduced. We also demonstrated that, at the genus level, some gut microbial markers, including Anaeromyxobacter, MND1, oc32, Haliangium, and Adurb.Bin063_1, showed potential for identifying coal-burning endemic fluorosis. Moreover, non-targeted metabolomics and correlation analysis revealed the changes in the metabolome, particularly the gut microbiota-derived tryptophan metabolites such as tryptamine, 5-hydroxyindoleacetic acid, and indoleacetaldehyde. Our results indicated that excessive fluoride might cause xenobiotic-mediated dysbiosis of human gut microbiota and metabolic disorders. These findings suggest that the alterations in gut microbiota and metabolome play vital roles in regulating disease susceptibility and multi-organ damage after excessive fluoride exposure.


Assuntos
Intoxicação por Flúor , Microbioma Gastrointestinal , Humanos , Fluoretos/análise , Carvão Mineral , RNA Ribossômico 16S , Intoxicação por Flúor/epidemiologia , Fezes/microbiologia , Metaboloma
18.
Exp Biol Med (Maywood) ; 248(1): 36-43, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36533575

RESUMO

The aim of this study was to investigate the expression of serum homocysteine (HCY), procalcitonin (PCT), and C-reactive protein (CRP) in abdominal infectious disease and analyze their relationship with the degree of abdominal infection. We conducted a retrospective study involving 157 patients with abdominal infections at Xuzhou Central Hospital between January 2016 and October 2019. The patients were composed of intestinal obstruction (73 cases), appendicitis (45 cases), perforation of the digestive tract (25 cases), and cholecystitis (14 cases). The HCY, PCT, and CRP levels of patients with abdominal infections were detected using enzyme-linked immunosorbent assay (ELISA), and correlation analysis between the HCY, PCT, and CRP levels and abdominal infection was performed using Pearson's correlation analysis. Compared with before treatment, the HCY, PCT, and CRP levels in the four groups decreased significantly after treatment. The levels in the patients in the intestinal obstruction group decreased more markedly than in those in the other groups. There were positive correlations among the HCY level, PCT, and CRP before treatment only in patients with intestinal obstruction (P < 0.001). The difference was statistically significant in the HCY level between the non-operation and the operation groups in patients with intestinal obstruction (P < 0.001). Serum HCY may be a valuable marker for predicting aggravation of infection in patients with intestinal obstruction.


Assuntos
Proteína C-Reativa , Homocisteína , Humanos , Estudos Retrospectivos , Proteína C-Reativa/metabolismo , Biomarcadores
19.
Nat Commun ; 14(1): 1504, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36932127

RESUMO

The Synaptotagmin-like Mitochondrial-lipid-binding Protein (SMP) domain is a newly identified lipid transfer module present in proteins that regulate lipid homeostasis at membrane contact sites (MCSs). However, how the SMP domain associates with the membrane to extract and unload lipids is unclear. Here, we performed in vitro DNA brick-assisted lipid transfer assays and in silico molecular dynamics simulations to investigate the molecular basis of the membrane association by the SMP domain of extended synaptotagmin (E-Syt), which tethers the tubular endoplasmic reticulum (ER) to the plasma membrane (PM). We demonstrate that the SMP domain uses its tip region to recognize the extremely curved subdomain of tubular ER and the acidic-lipid-enriched PM for highly efficient lipid transfer. Supporting these findings, disruption of these mechanisms results in a defect in autophagosome biogenesis contributed by E-Syt. Our results suggest a model that provides a coherent picture of the action of the SMP domain at MCSs.


Assuntos
Retículo Endoplasmático , Membranas Mitocondriais , Sinaptotagminas/genética , Sinaptotagminas/metabolismo , Membrana Celular/metabolismo , Retículo Endoplasmático/metabolismo , Membranas Mitocondriais/metabolismo , Lipídeos/análise
20.
Eur J Pharmacol ; 935: 175326, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36257381

RESUMO

The regulation of stem cell directional differentiation is a core research topic in regenerative medicine, and modulating the fate of stem cells is a promising strategy for precise intervention through the utilization of naturally small molecule compounds. The present study aimed to explore the potential pro-osteogenic differentiation effect of galangin, a flavonoid derived from Alpinia officinarum, on human amniotic mesenchymal stem cells (hAMSCs) and the underlying molecular mechanism. The results showed that galangin had no cytotoxicity towards hAMSCs when the concentration was less than 50 µM. Treatment with 10 µM galangin significantly increased alkaline phosphatase (ALP) secretion and calcium deposition in hAMSCs. Meanwhile, galangin upregulated the mRNA and protein expression of early osteoblast-specific markers, namely ALP, RUNX2, and OSX, and late osteoblast-specific markers, CoL1α1, OPN, and OCN, in hAMSCs. Furthermore, signaling pathway screening studies showed that galangin enhanced the phosphorylation of Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3). In addition, molecular docking results suggest there is a promising interaction between galangin and JAK2. Finally, treatment with the JAK2 specific inhibitor AG490 effectively reversed the induction of osteogenic differentiation, upregulation of osteoblast-specific marker expression, and activation of JAK2/STAT3 signaling induced by galangin. These results show that galangin induces the osteogenic differentiation of hAMSCs through the JAK2/STAT3 signaling pathway and could serve as a promising small molecular osteoinducer for application to hAMSCs in regenerative medicine.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Humanos , Janus Quinase 2/metabolismo , Fator de Transcrição STAT3/metabolismo , Simulação de Acoplamento Molecular , Diferenciação Celular , Flavonoides/farmacologia , Flavonoides/metabolismo , Transdução de Sinais
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