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1.
Exp Biol Med (Maywood) ; 247(11): 972-981, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35470702

RESUMO

Liver cancer (LC) is one of the most common malignant tumors worldwide. Since the mechanism of LC pathogenesis and metastasis cannot be carried out directly on the human body, it is particularly important to establish human liver cancer cell lines for research in vitro. In this study, tissue block adherence method combined with cell clumps digestion method was used to establish primary human hepatocytes (PHHs) with a successful rate of 60% (45/75). Short tandem repeat (STR) analysis proved the cells were derived from its paired tissues. These cells from hepatocellular carcinoma (HCC) expressed NTCP and secreted ALB and AAT as detected by western blot, and expressed hepatocyte-specific membrane protein ASGR1 as detected by flow cytometry. Liver cancer biomarkers like CK7 in ICC (intrahepatic cholangiocarcinoma), AFP, and GPC3 in HCC expressed of different degree as detected by immunohistochemical analysis. These cells displayed typical liver cancer cell morphological characteristics and can passage stably. In conclusion, we developed an effective method to establish PHHs. Further studies are necessary to study if these cells maintaining other liver function and reproduce the physiology of the tumors and how these cells behavior in the drug development.


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Receptor de Asialoglicoproteína/metabolismo , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/patologia , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patologia , Glipicanas/metabolismo , Hepatócitos/metabolismo , Humanos , Neoplasias Hepáticas/patologia
2.
Am J Transl Res ; 14(2): 942-954, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35273697

RESUMO

BACKGROUND: Chronic HBV infection is a serious worldwide health problem that mainly causes liver cirrhosis and hepatocellular carcinoma (HCC). Few studies have explored how T cell exhaustion helps HBV avoid immune system attack and how to reverse that exhaustion. Recently, T cell immunoglobulin and immune receptor tyrosine-based inhibitory motif (ITIM) domain (TIGIT) have been identified as coinhibitory receptors, similar to PD-1. This study explores the expression of TIGIT and the T cell function changes in patients with chronic HBV infection. RESULTS: In this study, we found that the expression of TIGIT on T cells increased significantly in patients with chronic HBV infection. High expression of TIGIT on T cells is associated with functional exhaustion. Importantly, this study demonstrates that blocking TIGIT can reverse T cell exhaustion and restore function in patients with chronic HBV infection. CONCLUSIONS: HBV induces T cell exhaustion by up-regulating the expression of TIGIT. Blocking the TIGIT/PVR signaling pathway can reverse T cell exhaustion, so this discovery provides an immunotherapy target to battle chronic HBV infection.

3.
Plant J ; 106(2): 351-365, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33486798

RESUMO

Lotus plumule, the embryo of the seed of the sacred lotus (Nelumbo nucifera), contains a high accumulation of secondary metabolites including flavonoids and possesses important pharmaceutical value. Flavonoid C-glycosides, which accumulate exclusively in lotus plumule, have attracted considerable attention in recent decades due to their unique chemical structure and special bioactivities. As well as mono-C-glycosides, lotus plumule also accumulates various kinds of di-C-glycosides by mechanisms which are as yet unclear. In this study we identified two C-glycosyltransferase (CGT) genes by mining sacred lotus genome data and provide in vitro and in planta evidence that these two enzymes (NnCGT1 and NnCGT2, also designated as UGT708N1 and UGT708N2, respectively) exhibit CGT activity. Recombinant UGT708N1 and UGT708N2 can C-glycosylate 2-hydroxyflavanones and 2-hydroxynaringenin C-glucoside, forming flavone mono-C-glycosides and di-C-glycosides, respectively, after dehydration. In addition, the above reactions were successfully catalysed by cell-free extracts from tobacco leaves transiently expressing NnCGT1 or NnCGT2. Finally, enzyme assays using cell-free extracts of lotus plumule suggested that flavone di-C-glycosides (vicenin-1, vicenin-3, schaftoside and isoschaftoside) are biosynthesized through sequentially C-glucosylating and C-arabinosylating/C-xylosylating 2-hydroxynaringenin. Taken together, our results provide novel insights into the biosynthesis of flavonoid di-C-glycosides by proposing a new biosynthetic pathway for flavone C-glycosides in N. nucifera and identifying a novel uridine diphosphate-glycosyltransferase (UGT708N2) that specifically catalyses the second glycsosylation, C-arabinosylating and C-xylosylating 2-hydroxynaringenin C-glucoside.


Assuntos
Flavonoides/metabolismo , Glicosídeos/metabolismo , Nelumbo/metabolismo , Glicosilação , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Redes e Vias Metabólicas , Nelumbo/enzimologia , Nelumbo/genética , Filogenia , Plantas Geneticamente Modificadas , Nicotiana
4.
Chem Biol Drug Des ; 97(2): 293-304, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32896083

RESUMO

Norcantharidin (NCTD), the demethylated analog of cantharidin isolated from Mylabris, is known to inhibit renal fibrosis. However, the underlying mechanism is largely unknown. The present study investigates whether NCTD exerts this effect through regulation of the protein phosphatase 2A catalytic subunit (PP2Ac)-Smad3 pathway. HK-2 human renal proximal tubule cells exposed to transforming growth factor (TGF)-ß1 were used as an in vitro model of renal fibrosis. The levels of total Smad3, C-terminal-phosphorylated Smad3 (p-Smad3), PP2Ac, and fibronectin (Fn) were evaluated by Western blotting. A PP2Ac overexpression plasmid and the PP2Ac inhibitor okadaic acid (OA) were used for functional analyses. The subcellular localization of Smad3 was visualized by immunofluorescence labeling. The results showed that PP2Ac overexpression increased Smad3 phosphorylation and nuclear translocation in HK-2 cells, while pharmacologic inhibition of PP2Ac with OA had the opposite effect. NCTD suppressed Fn and p-Smad3 expression and TGF-ß1-induced nuclear entry of Smad3, but these effects were abrogated by inhibition of PP2Ac. Thus, the anti-renal interstitial fibrosis effect of NCTD is exerted through inhibition of PP2Ac-mediated C-terminal phosphorylation of Smad3. These findings highlight the therapeutic potential of NCTD for the treatment of renal interstitial fibrosis.


Assuntos
Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Proteína Fosfatase 2/metabolismo , Proteína Smad3/metabolismo , Domínio Catalítico , Linhagem Celular , Fibronectinas/metabolismo , Humanos , Ácido Okadáico/farmacologia , Fosforilação/efeitos dos fármacos , Proteína Fosfatase 2/antagonistas & inibidores , Proteína Fosfatase 2/genética , Fator de Crescimento Transformador beta1/farmacologia
5.
J Sep Sci ; 42(18): 2888-2899, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31282097

RESUMO

Elm fruits were once an important food source in the years of famine. Research on the functional compounds in elm fruits was almost unavailable. In this study, we established an efficient high-performance liquid chromatography method for the simultaneous separation of eight chlorogenic acids and 28 flavonoids in elm fruits for the first time. Total flavonoid contents ranged from 286 mg/100 g (Ulmus laciniata) to 1228 mg/100 g (U. pumila). High concentrations of rutin, quercetin 3-O-glucoside, and kaempferol derivatives were present in U. laevis, U. castaneifolia, and U. pumila, respectively. Furthermore, the fruit extracts of U. americana, U. castaneifolia, U. davidiana, and U. pumila showed higher antioxidant activity. These results suggest that fruits of these species can be used as bioresources for the extraction of the corresponding functional compounds. This work provides informative data and can be an important reference for future research on elm fruits as a renewed food resource.


Assuntos
Antioxidantes/análise , Ácido Clorogênico/análise , Flavonoides/análise , Frutas/química , Ulmus/química , Antioxidantes/farmacologia , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Ácido Clorogênico/farmacologia , Flavonoides/farmacologia , Picratos/antagonistas & inibidores , Ácidos Sulfônicos/antagonistas & inibidores
6.
J Sep Sci ; 42(19): 3067-3076, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31347249

RESUMO

Ligustrazine was the active ingredient of the traditional Chinese medicine Chuanxiong Rhizoma. However, the content of ligustrazine is very low. We proposed a hypothesis that ligustrazine was produced by the mutual effects between endophytic Bacillus subtilis and the Ligusticum chuanxiong Hort. This study aimed to explore whether the endophytic B. subtilis LB5 could make use of Chuanxiong Rhizoma fermentation matrix to produce ligustrazine and clarify the mechanisms of action preliminarily. Ultra high performance liquid chromatography with quadrupole time-of-flight mass spectrometry analysis showed the content of ligustrazine in Chuanxiong Rhizoma was below the detection limit (0.1 ng/mL), while B. subtilis LB5 produced ligustrazine at the yield of 1.0268 mg/mL in the Chuanxiong Rhizoma-ammonium sulfate fermentation medium. In the fermented matrix, the reducing sugar had a significant reduction from 12.034 to 2.424 mg/mL, and rough protein content increased from 2.239 to 4.361 mg/mL. Acetoin, the biosynthetic precursor of ligustrazine, was generated in the Chuanxiong Rhizoma-Ammonium sulfate (151.2 mg/mL) fermentation medium. This result showed that the endophytic bacteria B. subtilis LB5 metabolized Chuanxiong Rhizoma via secreted protein to consume the sugar in Chuanxiong Rhizoma to produce a considerable amount of ligustrazine. Collectively, our preliminary research suggested that ligustrazine was the interaction product of endophyte, but not the secondary metabolite of Chuanxiong Rhizoma itself.


Assuntos
Bacillus subtilis/química , Medicamentos de Ervas Chinesas/análise , Pirazinas/análise , Rizoma/química , Bacillus subtilis/metabolismo , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/metabolismo , Fermentação , Espectrometria de Massas , Medicina Tradicional Chinesa , Pirazinas/metabolismo , Rizoma/metabolismo , Fatores de Tempo
7.
Medicine (Baltimore) ; 98(24): e15942, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31192930

RESUMO

Emergent resistance to antibiotics among Streptococcus pneumoniae isolates is a severe problem worldwide. Antibiotic resistance profiles for S pneumoniae isolates identified from pediatric patients in mainland China remains to be established.The clinical features, antimicrobial resistance, and multidrug resistance patterns of S pneumoniae were retrospectively analyzed at 10 children's hospitals in mainland China in 2016.Among the collected 6132 S pneumoniae isolates, pneumococcal diseases mainly occurred in children younger than 5 years old (85.1%). The resistance rate of S pneumoniae to clindamycin, erythromycin, tetracycline, and trimethoprim/sulfamethoxazole was 95.8%, 95.2%, 93.6%, and 66.7%, respectively. The resistance rates of S pneumoniae to penicillin were 86.9% and 1.4% in non-meningitis and meningitis isolates, while the proportions of ceftriaxone resistance were 8.2% and 18.1%, respectively. Pneumococcal conjugate vaccine was administered to only 4.1% of patients. Penicillin and ceftriaxone resistance, underling diseases, antibiotic resistant risk factors, and poor prognosis appeared more frequently in invasive pneumococcal diseases. The incidence of multidrug resistance (MDR) was 46.1% in patients with invasive pneumococcal disease which was more than in patients with non-invasive pneumococcal disease (18.3%). Patients with invasive pneumococcal disease usually have several MDR coexistence.S pneumoniae isolates showed high resistance to common antibiotics in mainland China. Penicillin and ceftriaxone resistance rate of invasive streptococcal pneumonia patients were significantly higher than that of non-invasive S pneumoniae patients. Alarmingly, 46.1% of invasive clinical isolates were multidrug resistant, so it is important to continued monitor the resistance of S pneumoniae when protein conjugate vaccine (PCV13) is coming in mainland China.


Assuntos
Antibacterianos/farmacologia , Infecções Pneumocócicas/epidemiologia , Streptococcus pneumoniae/isolamento & purificação , Ceftriaxona/farmacologia , Criança , Pré-Escolar , China/epidemiologia , Farmacorresistência Bacteriana Múltipla , Eritromicina/farmacologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Testes de Sensibilidade Microbiana , Penicilinas/farmacologia , Infecções Pneumocócicas/microbiologia , Estudos Retrospectivos , Streptococcus pneumoniae/efeitos dos fármacos , Combinação Trimetoprima e Sulfametoxazol/farmacologia
8.
Zhongguo Zhong Yao Za Zhi ; 43(19): 3893-3898, 2018 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-30453715

RESUMO

Ligustrazine is an important active ingredient of the traditional Chinese medicine Chuanxiong Rhizoma, but its content is a controversial topic. The endophytes of medicinal plants have the ability to produce the same active substances as the host, so this report focused on the endophytic Bacillus subtilis, to study the origin of ligustrazine in Chuanxiong Rhizoma preliminarily by inoculating the isolated endophytic B. subtilis to the Chuanxiong Rhizoma medium in vitro for solid state fermentation. Tissue grinding method was used to isolate the endogenetic B. subtilis. The morphological features, conventional physiological and biochemical reactions and 16S rRNA molecular techniques were combined to identify the endogenetic strains. Then, the strains that grew well in the medicinal matrix of Chuanxiong Rhizoma were screened out for further fermentation studies. The solid-state fermentation was performed at 37 °C for 30 d using Chuanxiong Rhizoma fermentation medium (40 g Chuanxiong Rhizoma powder, 100 mL sterile water, 121 °C, sterilization for 25 minutes). UPLC was used to detect the contents of ligustrazine, acetoin in the Chuanxiong Rhizoma fermentation medium and Chuanxiong Rhizoma. All the five strains were Gram-positive and had spores. Phylogenetic analysis of the 16S rRNA sequence showed that the endophytes were B. subtilis. The results of UPLC showed that ligustrazine was detected in the Chuanxiong Rhizoma fermentation medium inoculated with endogenetic B. subtilis LB3, LB3-2-1, LB4, LB5 and LB6-2, while not detected neither in blank Chuanxiong Rhizoma fermentation medium nor in Chuanxiong Rhizoma. This study showed that the endogenetic B. subtilis of Ligusticum chuanxiong Hort. can make use of Chuanxiong Rhizoma fermentation medium to produce ligustrazine. Endogenetic B. subtilis has a certain correlation with the accumulation of ligustrazine in Rhizoma Chuanxiong. We speculate that the ligustrazine may be derived from the catabolism of endogenetic B. subtilis in Ligusticum chuanxiong.


Assuntos
Bacillus subtilis , Ligusticum/química , Ligusticum/microbiologia , Pirazinas/análise , Endófitos , Fermentação , Filogenia , RNA Ribossômico 16S , Rizoma/química
9.
J Pharm Biomed Anal ; 161: 455-463, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30216794

RESUMO

Gentianopsis barbata, Halenia corniculata, and Gentianella acuta were widely distributed throughout China and commonly used in traditional Chinese medicine. However, owing to similar living environments and morphological features, locals often had trouble distinguishing between these three species. In this present study, chromatograms at 350 nm were obtained and the composition and content of their chemical compounds determined using HPLC-DAD/ESI-MS2. In total, 35 chemical compounds were detected, 32 of which were identified, 25 of which were xanthones, 6 flavonoids, and 1 chlorogenic acid. The 350 nm chromatograms of these three species displayed evident differences. The individual compounds and their occurrence and content in different parts of the plant within different species were included in our results. This basic data will be useful for future pharmacological study. The total compositions of flavonoids and xanthones were approximately comparable in G. barbata and H. corniculata. Meanwhile, xanthones were predominant in G. acuta. From the perspective of chemical compound compositions, the leaf is recommended as the most valuable medicinal section for each of these three species.


Assuntos
Ácido Clorogênico/análise , Medicamentos de Ervas Chinesas/química , Flavonoides/análise , Gentianaceae/química , Xantonas/análise , Cromatografia Líquida de Alta Pressão , Estruturas Vegetais/química , Espectrometria de Massas por Ionização por Electrospray
10.
Plant Sci ; 274: 212-222, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30080606

RESUMO

α-linolenic acid (ALA) deficiency and a skewed ω6: ω3 fatty acid ratio in the diet are thought to be a major cause for the high incidence of cardiovascular, inflammatory, and autoimmune diseases. Recent years, tree peony (Paeonia suffruticosa Andr.) with the high proportion of ALA (more than 45% in seed oil) is widely concerned. However, the underlying accumulation mechanism of the ALA in tree peony seeds remains unknown. In this study, comparative transcriptome analysis was performed between two cultivars ('Saiguifei' and 'Jingshenhuanfa') with different ALA contents. The analysis of the metabolic enzymes associated with ALA biosynthesis and temporal accumulation patterns of unsaturated fatty acids demonstrated the importance of microsomal ω-3 fatty acid desaturase 3 (FAD3). Moreover, PsFAD3 gene was identified from tree peony seeds, which was located in endoplasmic reticulum and the expression levels of PsFAD3 were consistent with ALA accumulation patterns in seeds. Heterologous expression in Saccharomyces cerevisiae and Arabidopsis thaliana confirmed that the isolated PsFAD3 protein could catalyze ALA synthesis. These results indicated that PsFAD3 was involved in the synthesis of ALA in seeds and could be exploited by the genetic breeding of new cultivars with high ALA content in tree peony as well as other potential crops.


Assuntos
Ácidos Graxos Dessaturases/metabolismo , Paeonia/enzimologia , Transcriptoma , Ácido alfa-Linolênico/metabolismo , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Insaturados/metabolismo , Paeonia/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/enzimologia , Sementes/genética
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