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1.
Saudi Pharm J ; 32(4): 101980, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38439949

RESUMO

Xanthine oxidase (XO) has been widely recognized as a pivotal enzyme in developing hyperuricemia, primarily contributing to the excessive production of uric acid during purine metabolism in the liver. One of the standard treatment approaches involves reducing uric acid levels by inhibiting XO activity. In this study, the leaf extract of Dolichandrone spathacea, traditionally used in folk medicine, was found to inhibit XO activity in the ethyl acetate and butanol fractions at a concentration of 100 µg/mL, their values were 78.57 ± 3.85 % (IC50 = 55.93 ± 5.73 µg/ml) and 69.43 ± 8.68 % (IC50 = 70.17 ± 7.98 µg/ml), respectively. The potential XO inhibitory components were isolated by bioactivity assays and the HR-ESI-MS and NMR spectra system. The main constituents of leaf extracts of Dolichandrone spathacea, six compounds, namely trans-4-methoxycinnamic acid (3), trans-3,4-dimethoxycinnamic acid (4), p-coumaric acid (5), martynoside (6), 6-O-(p-methoxy-E-cinnamoyl)-ajugol (7), and scolymoside (17), were identified as potent XO inhibitors with IC50 values ranging from 19.34 ± 1.63 µM to 64.50 ± 0.94 µM. The enzyme kinetics indicated that compounds 3-5, 7, and 17 displayed competitive inhibition like allopurinol, while compound 6 displayed a mixed-type inhibition. Computational studies corroborated these experimental results, highlighting the interactions between potential metabolites and XO enzyme. The hydrogen bonds played crucial roles in the binding interaction, especially, scolymoside (17) forms a hydrogen bond with Mos3004, exhibited the lowest binding energy (-18.3286 kcal/mol) corresponding to the lowest IC50 (19.34 ± 1.63 µM). Furthermore, nine compounds were isolated for the first time from this plant. In conclusion, Dolichandrone spathacea and its constituents possess the potential to modulate the xanthine oxidase enzyme involved in metabolism.

2.
Proc Natl Acad Sci U S A ; 117(4): 2004-2013, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31932432

RESUMO

Environmental cues such as nutrients alter cellular behaviors by acting on a wide array of molecular sensors inside cells. Of emerging interest is the link observed between effects of dietary sugars on cancer proliferation. Here, we identify the requirements of hexosamine biosynthetic pathway (HBP) and O-GlcNAc transferase (OGT) for Drosophila homeodomain-interacting protein kinase (Hipk)-induced growth abnormalities in response to a high sugar diet. On a normal diet, OGT is both necessary and sufficient for inducing Hipk-mediated tumor-like growth. We further show that OGT maintains Hipk protein stability by blocking its proteasomal degradation and that Hipk is O-GlcNAcylated by OGT. In mammalian cells, human HIPK2 proteins accumulate posttranscriptionally upon OGT overexpression. Mass spectrometry analyses reveal that HIPK2 is at least O-GlcNAc modified at S852, T1009, and S1147 residues. Mutations of these residues reduce HIPK2 O-GlcNAcylation and stability. Together, our data demonstrate a conserved role of OGT in positively regulating the protein stability of HIPKs (fly Hipk and human HIPK2), which likely permits the nutritional responsiveness of HIPKs.


Assuntos
Carcinogênese/patologia , Proteínas de Transporte/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Glucose/farmacologia , N-Acetilglucosaminiltransferases/metabolismo , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Acetilglucosamina/metabolismo , Animais , Carcinogênese/induzido quimicamente , Carcinogênese/metabolismo , Proteínas de Transporte/genética , Proliferação de Células , Células Cultivadas , Proteínas de Drosophila/genética , Drosophila melanogaster/efeitos dos fármacos , Drosophila melanogaster/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Células HEK293 , Humanos , Células MCF-7 , Camundongos , N-Acetilglucosaminiltransferases/genética , Fosforilação , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases/genética , Estabilidade Proteica , Edulcorantes/farmacologia
3.
Molecules ; 28(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37446726

RESUMO

Pinus morrisonicola Hayata is a unique plant species found in Taiwan. Previous studies have identified its anti-hypertensive, anti-oxidative, and anti-inflammatory effects. In this study, a bioactivity-guided approach was employed to extract 20 compounds from the ethyl acetate fraction of the ethanol extract of Pinus morrisonicola Hayata's pine needles. The anti-aging effects of these compounds were investigated using HT-1080 cells. The structures of the purified compounds were confirmed through NMR and LC-MS analysis, revealing the presence of nine flavonoids, two lignans, one coumarin, one benzofuran, one phenylic acid, and six diterpenoids. Among them, PML18, PML19, and PML20 were identified as novel diterpene. Compounds 3, 4, and 5 exhibited remarkable inhibitory effects against MMP-2 and showed no significant cell toxicity at 25 µM. Although the purified compounds showed lower activity against Pro MMP-2 and Pro MMP-9 compared to the ethyl acetate fraction, we speculate that this is the result of synergistic effects.


Assuntos
Lignanas , Pinus , Metaloproteinase 2 da Matriz , Pinus/química , Lignanas/química , Extratos Vegetais/química , Folhas de Planta/química
4.
Gut ; 70(12): 2349-2358, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33303567

RESUMO

OBJECTIVE: HCV prevails in uremic haemodialysis patients. The current study aimed to achieve HCV microelimination in haemodialysis centres through a comprehensive outreach programme. DESIGN: The ERASE-C Campaign is an outreach programme for the screening, diagnosis and group treatment of HCV encompassing 2323 uremic patients and 353 medical staff members from 18 haemodialysis centres. HCV-viremic subjects were linked to care for directly acting antiviral therapy or received on-site sofosbuvir/velpatasvir therapy. The objectives were HCV microelimination (>80% reduction of the HCV-viremic rate 24 weeks after the end of the campaign in centres with ≥90% of the HCV-viremic patients treated) and 'No-C HD' (no HCV-viremic subjects at the end of follow-up). RESULTS: At the preinterventional screening, 178 (7.7%) uremic patients and 2 (0.6%) staff members were HCV-viremic. Among them, 146 (83.9%) uremic patients received anti-HCV therapy (41 link-to-care; 105 on-site sofosbuvir/velpatasvir). The rates of sustained virological response (SVR12, undetectable HCV RNA 12 weeks after the end of treatment) in the full analysis set and per-protocol population were 89.5% (94/105) and 100% (86/86), respectively, in the on-site treatment group, which were comparable with the rates of 92.7% (38/41) and 100% (38/38), respectively, in the link-to-care group. Eventually, the HCV-viremic rate decreased to 0.9% (18/1,953), yielding an 88.3% reduction from baseline. HCV microelimination and 'No-C HD' were achieved in 92.3% (12/13) and 38.9% (7/18) of the haemodialysis centres, respectively. CONCLUSION: Outreach strategies with mass screenings and on-site group treatment greatly facilitated HCV microelimination in the haemodialysis population. CLINICALTRIALSGOV IDENTIFIER: NCT03803410 and NCT03891550.


Assuntos
Unidades Hospitalares de Hemodiálise/organização & administração , Hepatite C/prevenção & controle , Diálise Renal , Uremia/terapia , Viremia/prevenção & controle , Viremia/virologia , Antivirais/uso terapêutico , Carbamatos/uso terapêutico , Combinação de Medicamentos , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Humanos , Programas de Rastreamento , Projetos Piloto , Estudos Soroepidemiológicos , Sofosbuvir/uso terapêutico , Resposta Viral Sustentada , Taiwan
5.
J Biol Chem ; 295(46): 15742-15753, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-32913123

RESUMO

ADAMTSL2 mutations cause an autosomal recessive connective tissue disorder, geleophysic dysplasia 1 (GPHYSD1), which is characterized by short stature, small hands and feet, and cardiac defects. ADAMTSL2 is a matricellular protein previously shown to interact with latent transforming growth factor-ß binding protein 1 and influence assembly of fibrillin 1 microfibrils. ADAMTSL2 contains seven thrombospondin type-1 repeats (TSRs), six of which contain the consensus sequence for O-fucosylation by protein O-fucosyltransferase 2 (POFUT2). O-fucose-modified TSRs are subsequently elongated to a glucose ß1-3-fucose (GlcFuc) disaccharide by ß1,3-glucosyltransferase (B3GLCT). B3GLCT mutations cause Peters Plus Syndrome (PTRPLS), which is characterized by skeletal defects similar to GPHYSD1. Several ADAMTSL2 TSRs also have consensus sequences for C-mannosylation. Six reported GPHYSD1 mutations occur within the TSRs and two lie near O-fucosylation sites. To investigate the effects of TSR glycosylation on ADAMTSL2 function, we used MS to identify glycan modifications at predicted consensus sequences on mouse ADAMTSL2. We found that most TSRs were modified with the GlcFuc disaccharide at high stoichiometry at O-fucosylation sites and variable mannose stoichiometry at C-mannosylation sites. Loss of ADAMTSL2 secretion in POFUT2-/- but not in B3GLCT-/- cells suggested that impaired ADAMTSL2 secretion is not responsible for skeletal defects in PTRPLS patients. In contrast, secretion was significantly reduced for ADAMTSL2 carrying GPHYSD1 mutations (S641L in TSR3 and G817R in TSR6), and S641L eliminated O-fucosylation of TSR3. These results provide evidence that abnormalities in GPHYSD1 patients with this mutation are caused by loss of O-fucosylation on TSR3 and impaired ADAMTSL2 secretion.


Assuntos
Proteínas ADAMTS/metabolismo , Doenças do Desenvolvimento Ósseo/patologia , Proteínas da Matriz Extracelular/metabolismo , Deformidades Congênitas dos Membros/patologia , Proteínas ADAMTS/química , Proteínas ADAMTS/genética , Sequência de Aminoácidos , Animais , Doenças do Desenvolvimento Ósseo/genética , Sistemas CRISPR-Cas/genética , Dissacarídeos/química , Proteínas da Matriz Extracelular/química , Proteínas da Matriz Extracelular/genética , Fucosiltransferases/deficiência , Fucosiltransferases/genética , Edição de Genes , Glicosilação , Glicosiltransferases/deficiência , Glicosiltransferases/genética , Células HEK293 , Humanos , Deformidades Congênitas dos Membros/genética , Manose/química , Camundongos , Mutagênese Sítio-Dirigida , Domínios Proteicos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Alinhamento de Sequência
6.
J Formos Med Assoc ; 120(1 Pt 2): 303-310, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33109431

RESUMO

BACKGROUND: The biochemical response is a crucial indicator of prognosis in chronic hepatitis B (CHB) patients treated with nucleotide/nucleoside analogues (NAs). The impact of hepatitis D virus (HDV) infection on alanine aminotransferase normalization is elusive. METHODS: The longitudinal study recruited 1185 CHB patients who received NAs. These patients were tested for anti-HDV antibody and HDV RNA at the initiation of anti-hepatitis B virus (HBV) therapy and annually for patients who were HDV-seropositive. ALT levels were examined at the first and second year of anti-HBV therapy. ALT abnormality was defined as ALT levels above 40 IU/mL in both male and female, and the risk factors associated with ALT abnormality were analysed. RESULTS: Rates of seropositivity for anti-HDV and HDV RNA were 2.0% and 0.8% among 1185 NA-treated CHB patients, respectively. The strongest factor associated with ALT abnormality (>40 IU/mL) after first year treatment with NAs was HDV RNA seropositivity at year 1 (odds ratio [OR]/95% confidence interval [CI]: 31.44/3.49-283.56, P = 0.002), followed by liver cirrhosis (2.18/1.51-3.15, P < 0.001), detectable HBV DNA at year 1 (OR/CI: 1.99/1.36-2.92, P < 0.001), diabetes (OR/CI: 1.75/1.10-2.78, P = 0.02), body mass index (BMI) (OR/CI: 1.13/1.09-1.18, P < 0.001) and age (OR/CI: 0.97/0.96-0.98, P < 0.001). Among patients who were seronegative for HBV DNA at year 1, the strongest factor associated with ALT abnormality was HDV RNA seropositivity at year 1 (OR/CI: 30.00/3.28-274.05, P = 0.003), followed by liver cirrhosis (OR/CI: 1.83/1.21-2.75, P = 0.004), BMI (OR/CI: 1.16/1.11-1.21, P < 0.001) and age (OR/CI: 0.97/0.96-0.99, P < 0.001). Similarly, the impact of HDV RNA seropositivity on ALT abnormality was noted in patients without detectable HBV DNA but not in those with hepatitis B viremia at treatment year 2 (OR/CI: 10.16/1.33-77.74, P = 0.03). CONCLUSION: HDV infection played an important role in ALT abnormality in CHB patients receiving 1-year and 2-year NAs. The impact was particularly noted in patients who had successfully suppressed HBV DNA.


Assuntos
Hepatite B Crônica , Vírus Delta da Hepatite , Nucleosídeos/uso terapêutico , Nucleotídeos/uso terapêutico , Alanina Transaminase , DNA Viral , Feminino , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Hepatite D , Vírus Delta da Hepatite/genética , Humanos , Estudos Longitudinais , Masculino
7.
J Gastroenterol Hepatol ; 35(11): 1886-1892, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32247291

RESUMO

BACKGROUND AND AIM: The serial serologic changes of hepatitis D virus (HDV) infection among chronic hepatitis B virus (HBV) infected patients who received oral nucleotide/nucleoside analogues are elusive. METHODS: Serum anti-HDV and HDV RNA among chronic hepatitis B (CHB) patients were tested at the time of initiating anti-HBV therapy and subsequently during the follow-up period. RESULTS: The seropositive rate of anti-HDV and HDV RNA among 2850 CHB patients, was 2.7% and 0.9%, respectively. Factors associated with anti-HDV seropositivity were platelet counts (odds ratio [OR]/95% confidence intervals [CI]: 0.995/0.992-0.999; P = 0.006), HBV DNA levels (OR/CI: 0.81/0.70-0.94; P = 0.005), and hepatitis B e-antigen (HBeAg) seropositivity (OR/CI: 0.22/0.05-0.95; P = 0.04). The only factor associated with HDV RNA positivity among anti-HDV seropositive patients was age (OR/CI: 0.95/0.90-1.00; P = 0.03). The spontaneous clearance rate of serum anti-HDV antibody was 3.0 per 100 person-years with a median follow-up period of 3.5 years (range 2-12 years), whereas the seroclearance rate of HDV RNA was 4.3 per 100 person-years among anti-HDV seropositive patients after a median follow-up period of 6.0 years (range 2-11 years). A baseline anti-HDV titer < 0.5 cut-off index was the only factor predictive of anti-HDV seroclearance (hazard ratio [HR]/CI: 30.11/3.73-242.85; P = 0.001). CONCLUSIONS: HDV infection was not common among patients treated for HBV in Taiwan. Seroclearance of anti-HDV and HDV RNA did occur over time, albeit the chance is rare.


Assuntos
Anticorpos Antivirais/sangue , Coinfecção/diagnóstico , Coinfecção/virologia , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Hepatite D/diagnóstico , Hepatite D/virologia , Nucleosídeos/análogos & derivados , Nucleosídeos/administração & dosagem , RNA Viral/sangue , Testes Sorológicos , Administração Oral , Fatores Etários , Feminino , Seguimentos , Vírus Delta da Hepatite/genética , Vírus Delta da Hepatite/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Taiwan , Fatores de Tempo
8.
Int J Mol Sci ; 21(14)2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32668728

RESUMO

Hepatitis C virus (HCV) infections can cause permanent liver-related diseases, including hepatocellular carcinoma (HCC). Low mortality and incidence of HCC have been observed in patients with chronic hepatitis C undergoing direct-acting antiviral therapy. Tumor suppressive let-7 family members are down-regulated in HCC. The present study, therefore, aimed to investigate whether expression levels for the full spectrum of let-7 family members (let-7a, 7b, 7c, 7d, 7e, 7f, 7g, 7i, and miR-98) in the circulatory system are useful as surveillance biomarkers for liver-related diseases to monitor treatment efficacy during HCV infection. To this end, we measured the levels of mature circulating let-7 family members using quantitative reverse transcription-PCR in 236 patients with HCV infection, and 147 age- and sex-matched controls. Using hierarchical cluster analysis and principal component analysis, three clusters were obtained after measuring expression levels of let-7 family members in the patients and controls. Cluster 1 included let-7a/d/e/g, Cluster 2 comprised let-7b and let-7i, and Cluster 3 comprised let-7c/f/miR-98. Let-7b/c/g represented the three clusters and showed the best survival response to liver cancer when analyzed with respect to patient data. Therefore, considering the circulating levels of let7 b/c/g as representatives of the let-7 family may facilitate effective monitoring of liver-related disease.


Assuntos
Genes Supressores de Tumor , Hepatite C Crônica/sangue , MicroRNAs/sangue , Família Multigênica , Idoso , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Biomarcadores , Contagem de Células Sanguíneas , Glicemia/análise , Creatinina/sangue , Feminino , Hepatite C Crônica/genética , Humanos , Estimativa de Kaplan-Meier , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , gama-Glutamiltransferase/sangue
9.
J Infect Dis ; 219(8): 1224-1233, 2019 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-30452671

RESUMO

BACKGROUND: We aimed to investigate the long-term outcomes in hepatitis B (HBV)/hepatitis C virus (HCV) dual-infected patients after anti-HCV therapy. METHODS: A total of 192 HBV/HCV dual-infected patients who had received pegylated interferon treatment were recruited. The investigation outcomes included HBV DNA ≥2000 IU/mL, with or without alanine aminotransferase (ALT) ≥2-fold the upper limit of normal, and hepatitis B surface antigen (HBsAg) seroclearance. RESULTS: Four (2.1%) patients developed early HBV reactivation before the end of treatment. Fifty (26.6%) of the remaining patients had an episode of HBV DNA ≥2000 IU/mL in a mean follow-up of 68.8 months. The risk was 4.6 per 100 person years. Only 19 (10.1%) patients developed concomitant ALT flare with oral HBV antiviral therapy; the risk was 1.7 per 100 person years. Despite HBV flare, 67 (34.9%) patients had a favorable outcome of HBsAg seroclearance. The probability was 5.7 per 100 person years. A pretreatment HBV DNA level of 300 IU/mL served as an independent predictor for all the outcomes. The combined pretreatment HBV DNA level and HCV response further enhanced the prediction of HBV flare and HBsAg seroclearance. CONCLUSIONS: A pretreatment HBV DNA level of 300 IU/mL predicts HBV flare and HBsAg seroclearance after anti-HCV therapy.


Assuntos
Antivirais/uso terapêutico , Coinfecção/virologia , Hepatite B/complicações , Hepatite C/complicações , Carga Viral , Alanina Transaminase/sangue , Coinfecção/tratamento farmacológico , Feminino , Hepacivirus , Hepatite B/tratamento farmacológico , Hepatite B/virologia , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Resultado do Tratamento
10.
Nat Chem Biol ; 13(2): 161-167, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27918560

RESUMO

N-Acetylglucosamine ß-O-linked to nucleocytoplasmic proteins (O-GlcNAc) is implicated in the regulation of gene expression in organisms, from humans to Drosophila melanogaster. Within Drosophila, O-GlcNAc transferase (OGT) is one of the Polycomb group proteins (PcGs) that act through Polycomb group response elements (PREs) to silence homeotic (HOX) and other PcG target genes. Using Drosophila, we identify new O-GlcNAcylated PcG proteins and develop an antibody-free metabolic feeding approach to chemoselectively map genomic loci enriched in O-GlcNAc using next-generation sequencing. We find that O-GlcNAc is distributed to specific genomic loci both in cells and in vivo. Many of these loci overlap with PREs, but O-GlcNAc is also present at other loci lacking PREs. Loss of OGT leads to altered gene expression not only at loci containing PREs but also at loci lacking PREs, including several heterochromatic genes. These data suggest that O-GlcNAc acts through multiple mechanisms to regulate gene expression in Drosophila.


Assuntos
Acetilglucosamina/metabolismo , Drosophila melanogaster/genética , Genoma de Inseto , Proteínas do Grupo Polycomb/química , Proteínas do Grupo Polycomb/metabolismo , Animais , Drosophila melanogaster/enzimologia , Proteínas do Grupo Polycomb/genética
11.
BMC Genomics ; 19(Suppl 10): 904, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30598081

RESUMO

BACKGROUND: Human gut microbiome has an essential role in human health and disease. Although the major dominant microbiota within individuals have been reported, the change of gut microbiome caused by external factors, such as antibiotic use and bowel cleansing, remains unclear. We conducted this study to investigate the change of gut microbiome in overweight male adults after bowel preparation, where none of the participants had been diagnosed with any systemic diseases. METHODS: A total of 20 overweight, male Taiwanese adults were recruited, and all participants were omnivorous. The participants provided fecal samples and blood samples at three time points: prior to bowel preparation, 7 days after colonoscopy, and 28 days after colonoscopy. The microbiota composition in fecal samples was analyzed using 16S ribosome RNA gene amplicon sequencing. RESULTS: Our results demonstrated that the relative abundance of the most dominant bacteria hardly changed from prior to bowel preparation to 28 days after colonoscopy. Using the ratio of Prevotella to the sum of Prevotella and Bacteroides in the fecal samples at baseline, the participants were separated into two groups. The fecal samples of the Type 1 group was Bacteroides-dominant, and that of the Type 2 group was Prevotella-dominant with a noticeable presence Bacteroides. Bulleidia appears more in the Type 1 fecal samples, while Akkermensia appears more in the Type 2 fecal samples. Of each type, the gut microbial diversity differed slightly among the three collection times. Additionally, the Type 2 fecal microbiota was temporarily susceptible to bowel cleansing. Predictive functional analysis of microbial community reveals that their activities for the mineral absorption metabolism and arachidonic acid metabolism differed significantly between the two types. Depending on their fecal type, the variance of triglycerides and C-reactive protein also differed between the two types of participants. CONCLUSIONS: Depending upon the fecal type, the microbial diversity and the predictive functional modules of microbial community differed significantly after bowel preparation. In addition, blood biochemical markers presented somewhat associated with fecal type. Therefore, our results might provide some insights as to how knowledge of the microbial community could be used to promote health through personalized clinical treatment.


Assuntos
Fezes/microbiologia , Microbioma Gastrointestinal , Sobrepeso/microbiologia , Adulto , Biodiversidade , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
J Am Chem Soc ; 140(45): 15300-15308, 2018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-30296064

RESUMO

The modification of proteins with O-linked N-acetylglucosamine ( O-GlcNAc) by the enzyme O-GlcNAc transferase (OGT) has emerged as an important regulator of cellular physiology. Metabolic labeling strategies to monitor O-GlcNAcylation in cells have proven of great value for uncovering the molecular roles of O-GlcNAc. These strategies rely on two-step labeling procedures, which limits the scope of experiments that can be performed. Here, we report on the creation of fluorescent uridine 5'-diphospho- N-acetylglucosamine (UDP-GlcNAc) analogues in which the N-acyl group of glucosamine is modified with a suitable linker and fluorophore. Using human OGT, we show these donor sugar substrates permit direct monitoring of OGT activity on protein substrates in vitro. We show that feeding cells with a corresponding fluorescent metabolic precursor for the last step of the hexosamine biosynthetic pathway (HBP) leads to its metabolic assimilation and labeling of O-GlcNAcylated proteins within live cells. This one-step metabolic feeding strategy permits labeling of O-GlcNAcylated proteins with a fluorescent glucosamine-nitrobenzoxadiazole (GlcN-NBD) conjugate that accumulates in a time- and dose-dependent manner. Because no genetic engineering of cells is required, we anticipate this strategy should be generally amenable to studying the roles of O-GlcNAc in cellular physiology as well as to gain an improved understanding of the regulation of OGT within cells. The further expansion of this one-step in-cell labeling strategy should enable performing a range of experiments including two-color pulse chase experiments and monitoring OGT activity on specific protein substrates in live cells.


Assuntos
Acetilglucosamina/química , Fluorescência , N-Acetilglucosaminiltransferases/química , Acetilglucosamina/metabolismo , Glicosilação , Células HeLa , Humanos , Estrutura Molecular , N-Acetilglucosaminiltransferases/metabolismo
13.
J Formos Med Assoc ; 117(6): 497-504, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28694000

RESUMO

BACKGROUND/PURPOSE: The role of directly-acting antivirals (DAA)-containing regimens in the treatment of patients dually-infected with hepatitis C virus (HCV) and hepatitis B virus (HBV) remains unclear. The pilot study aimed to explore the safety and efficacy of a protease inhibitor, boceprevir, in combination with peginterferon/ribavirin for HCV genotype 1 (HCV-1)/HBV dually-infected patients refractory to prior peginterferon/ribavirin. METHODS: Twelve peginterferon-experienced patients dually-infected with HCV-1/HBV were assigned to receive boceprevir 800 mg, twice a day, plus peginterferon-α 2b 1.5 µg/kg/week and ribavirin 800-1400 mg/day for 36 or 48 weeks. The primary endpoint was HCV sustained virological response (SVR, HCV RNA undetectable 24 weeks after end-of-treatment). RESULTS: Five patients terminated treatment early due to adverse events (one at week 4, one at week 46), virological failures (one non-response and one breakthrough), and patient request (n = 1). Eight patients achieved HCV SVR (66.7% in full-analysis set and 72.7% in modified intention-to-treat population). The HCV SVR rate was 71.4% (5/7) in prior relapsers, 60.0% (3/5) in prior null responder; 75% in non-cirrhotic and 50% in cirrhotic patients. All four patients of prior non-cirrhotic relapsers received 36-week regimen and achieved HCV SVR. There was no HBV-related hepatic flare. All patients experienced at least one adverse event. Two had serious adverse events. CONCLUSION: Boceprevir plus peginterferon/ribavirin is effective in the treatment of HCV-1/HBV dually infected patients' refractory to prior peginterferon/ribavirin combination therapy.


Assuntos
Hepatite B/tratamento farmacológico , Hepatite C/tratamento farmacológico , Interferon-alfa/administração & dosagem , Polietilenoglicóis/administração & dosagem , Prolina/análogos & derivados , Ribavirina/administração & dosagem , Adulto , Antivirais/uso terapêutico , Quimioterapia Combinada , Feminino , Hepacivirus/genética , Hepatite B/complicações , Vírus da Hepatite B/genética , Hepatite C/complicações , Humanos , Interferon alfa-2 , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Polietilenoglicóis/efeitos adversos , Prolina/administração & dosagem , Prolina/efeitos adversos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Recidiva , Ribavirina/efeitos adversos , Resposta Viral Sustentada , Taiwan , Carga Viral , Adulto Jovem
14.
J Formos Med Assoc ; 117(1): 54-62, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28389143

RESUMO

BACKGROUND/PURPOSE: Pegylated interferon (PegIFN) plus ribavirin (RBV) combination therapy has been the standard of care since 2002. Although a better viral response has been achieved among chronic hepatitis C (CHC) patients in Taiwan, approximately 25% of hepatitis C virus (HCV) genotype 1 (G1) patients and 15% of G2 patients failed to achieve a sustained virological response (SVR) at the first therapy. The actual cost-effectiveness of the retreatment remains elusive. The present study conducted a real-world cost-effectiveness analysis of a large cohort among different pre-specified subgroups of treatment-experienced CHC patients. METHODS: A total of 117 patients with CHC who failed to achieve SVR at the first IFN-based therapy and received a second IFN-based therapy were enrolled. The inpatient and outpatient costs were acquired from National Health Insurance Research Database of Taiwan. The related medical care costs per treatment and per SVR were calculated. RESULTS: We demonstrated that the average cost per SVR achieved was $13,722 in treatment-experienced CHC patients. Especially, patients with HCV G1 infection, baseline viral loads > 400,000 IU/mL, advanced hepatic fibrosis, not achieving a rapid viral response at week 4 or complete early viral response at week 12, had poorer cost-effectiveness for PegIFN/RBV retherapy, ranging from around $15,520 to as high as $72,546 per SVR achieved. CONCLUSION: In the current study, we explored the real-world cost-effectiveness data of PegIFN/RBV for different subgroups of treatment-experienced HCV patients. These findings provide information for policy-makers for making decisions on treatment strategies of costly direct-acting antiviral agents for retreating CHC patients.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/economia , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Idoso , Estudos de Coortes , Análise Custo-Benefício , Quimioterapia Combinada , Feminino , Hepacivirus/genética , Humanos , Masculino , Pessoa de Meia-Idade , Resposta Viral Sustentada , Taiwan , Carga Viral
15.
Nat Chem Biol ; 11(5): 319-25, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25774941

RESUMO

Nucleocytoplasmic glycosylation of proteins with O-linked N-acetylglucosamine residues (O-GlcNAc) is recognized as a conserved post-translational modification found in all metazoans. O-GlcNAc has been proposed to regulate diverse cellular processes. Impaired cellular O-GlcNAcylation has been found to lead to decreases in the levels of various proteins, which is one mechanism by which O-GlcNAc seems to exert its varied physiological effects. Here we show that O-GlcNAcylation also occurs cotranslationally. This process protects nascent polypeptide chains from premature degradation by decreasing cotranslational ubiquitylation. Given that hundreds of proteins are O-GlcNAcylated within cells, our findings suggest that cotranslational O-GlcNAcylation may be a phenomenon regulating proteostasis of an array of nucleocytoplasmic proteins. These findings set the stage to assess whether O-GlcNAcylation has a role in protein quality control in a manner that bears similarity with the role played by N-glycosylation within the secretory pathway.


Assuntos
Acetilglucosamina/química , Peptídeos/química , Animais , Glicosilação , Células HEK293 , Humanos , Camundongos , Camundongos Knockout , N-Acetilglucosaminiltransferases/metabolismo , Plasmídeos , Processamento de Proteína Pós-Traducional , Receptores Citoplasmáticos e Nucleares/efeitos dos fármacos , Fator de Transcrição Sp1/química , Ubiquitinação
16.
J Gastroenterol Hepatol ; 32(10): 1754-1762, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28230928

RESUMO

BACKGROUND AND AIM: Hepatitis B virus (HBV) may reactivate when treating chronic hepatitis C (CHC) with direct acting antivirals (DAA). We aim to investigate the risk of HBV reactivation during DAA therapy. METHODS: Chronic hepatitis C patients receiving pan-oral DAA therapy from December 2013 to August 2016 were evaluated. Fifty-seven patients that had a past HBV infection (negative hepatitis B surface antigen [HBsAg] and positive hepatitis B core antibody) and seven patients that had a current HBV infection (positive HBsAg) were enrolled. Serum HBV and hepatitis C virus (HCV) markers were regularly measured. The endpoints were the HCV sustained virological response (SVR) and the HBV virological/clinical reactivation. RESULTS: The overall SVR12 rate was 96.9%, and two patients, one with positive HBsAg, had a relapse of HCV. No episodes of HBV virological reactivation were observed among the patients with a past HBV infection. For the seven patients with a current HBV infection, HBV virological reactivation was found in four (57.1%) of the seven patients. Clinical reactivation of HBV was observed in one patient with pretreatment detectable HBV DNA and recovered after entecavir administration. For the other three patients with HBV virological reactivation, the reappearance of low level HBV DNA without clinical reactivation was observed. HBsAg levels demonstrated only small fluctuations in all the patients. CONCLUSIONS: There was a minimal impact of hepatitis B core antibody seropositivity on HCV efficacy and safety. For CHC patients with current HBV infection, the risk of HBV reactivation was present, and monitoring the HBV DNA level during therapy is warranted.


Assuntos
Antivirais/administração & dosagem , Coinfecção/virologia , Vírus da Hepatite B/fisiologia , Hepatite B/virologia , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Ativação Viral , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Antivirais/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Chem Biodivers ; 11(6): 949-61, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24934680

RESUMO

Three new compounds, hypoxyloamide (1), 8-methoxynaphthalene-1,7-diol (2), and hypoxylonol (3), together with seven compounds isolated from nature for the first time, investiamide (4), hypoxypropanamide (5), hypoxylonol A (6), investienol (7), 2-heptylfuran (8), (3S)-5-methyl-8-O-methylmellein (9), (4R)-O-methylsclerone (10), along with 19 known compounds, 11-29, were isolated from the culture broth of Hypoxylon investiens BCRC 10F0115, a fungal endophyte residing in the stems of an endemic Formosan plant Litsea akoensis var. chitouchiaoensis. The structures of the new compounds were established by spectroscopic methods, including UV, IR, HR-ESI-MS, and extensive 1D- and 2D-NMR techniques. Of these isolates, 2, 8-methoxynaphthalen-1-ol (15), and 1,8-dimethoxynaphthalene (16) showed nitric oxide (NO) inhibitory activity with IC50 values of 11.8±0.9, 17.8±1.1, and 13.3±0.5 µM, respectively, stronger than the positive control quercetin (IC50 36.8±1.3 µM). Compounds 2, 15, and 16 also showed interleukin-6 (IL-6) inhibitory activity with IC50 values of 9.2±1.7, 18.0±0.6, and 2.0±0.1 µM, stronger than the positive control quercetin (IC50 31.3±1.6 µM). To the best of our knowledge, this is the first report on guaiane sesquiterpene metabolites, 3, 6, and 7, from the genus Hypoxylon.


Assuntos
Endófitos/química , Interleucina-6/biossíntese , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Óxido Nítrico/biossíntese , Sesquiterpenos de Guaiano/farmacologia , Xylariales/química , Animais , Relação Dose-Resposta a Droga , Litsea/microbiologia , Camundongos , Estrutura Molecular , Caules de Planta/microbiologia , Sesquiterpenos de Guaiano/química , Sesquiterpenos de Guaiano/isolamento & purificação , Relação Estrutura-Atividade
18.
Colloids Surf B Biointerfaces ; 234: 113692, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38104466

RESUMO

Different types and ratios of surfactant, co-surfactant, and oil phase, have a greater impact on nanoemulsion preparation. The presence of surfactants in the nanoemulsion can reduce surface tension and characteristic stability. In this study, four groups of oil-in-water (O/W) nanoemulsions (NEs) with different ratios of surfactant and co-surfactant, and two oils were formulated as carriers of Rhodiola rosea. The variable optimization was investigated and then indicated as optimization group A (Opt A) with the formula of 10% of transcutol, 16.63% of tween 80, Opt B with 10% of tween 80, 29.87% of span 80, Opt C with 28.42% of transcutol, 30% of labrasol, and Opt D with 30% of transcutol, 30% of tween 80. Labrafac and soybean oil were used as the oil phase. The optimized formula using the response surface method (RSM) by design expert software showed the ideal conditions with a higher desirability score. Desirability score are 0.72% (Opt A), 0.81% (Opt B), 0.76% (Opt C) and 0.98% (Opt D), the desirability rating close to 1 indicates a high possibility that the projected values would closely match the experimental results for the optimum formula. All of the optimized formulation were also checked for the characteristics of nanoemulsion including particle size, polydispersity index (PDI), zeta potential, viscosity, encapsulation efficiency, transmission electron microscope (TEM), antioxidant activity, skin irritation test and stability studies. Our study provides a promising combination of surfactant-co-surfactant and oil phases to produce a stable nanoemulsion that can be used in pharmaceuticals and cosmetics in the future.


Assuntos
Etilenoglicóis , Rhodiola , Tensoativos , Polissorbatos , Tamanho da Partícula , Óleos , Água , Emulsões
19.
Chem Biodivers ; 10(2): 303-12, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23418178

RESUMO

An investigation on the secondary metabolites from the BuOH extract of the fermentation broth of the thermotolerant polyester-degrading actinomycete Actinomadura miaoliensis BCRC 16873 was carried out. One previously undescribed α-pyrone (=pyran-2-one) derivative, designated as miaolienone (1), and a new butanolide, miaolinolide (2), together with 13 known compounds, 3-15, were obtained. Their structures were established on the basis of extensive 1D- and 2D-NMR analyses in combination with HR-MS experiments. In addition, the isolated compounds 1-15 were evaluated for the inhibitory effects of the isolates on the production of tumor necrosis factor (TNF-α) induced by lipopolysaccharide (LPS). Among the isolates, 1 and 2 significantly inhibited TNF-α production in U937 cells in vitro, and the IC(50) values were 0.59 and 0.76 µM, respectively. Compounds 3-5 displayed moderate inhibitory activities on LPS-induced TNF-α production.


Assuntos
4-Butirolactona/análogos & derivados , Actinomycetales/química , Lipopolissacarídeos/imunologia , Pironas/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , 4-Butirolactona/química , 4-Butirolactona/isolamento & purificação , 4-Butirolactona/fisiologia , Linhagem Celular , Humanos , Pironas/química , Pironas/isolamento & purificação , Microbiologia do Solo , Fator de Necrose Tumoral alfa/imunologia
20.
J Microbiol Immunol Infect ; 56(3): 586-597, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37188573

RESUMO

OBJECTIVES: Gaps in linkage-to-care remain the barriers toward hepatitis C virus (HCV) elimination in the directly-acting-antivirals (DAA) era, especially during SARS Co-V2 pandemics. We established an outreach project to target HCV micro-elimination in HCV-hyperendemic villages. METHODS: The COMPACT provided "door-by-door" screening by an "outreach HCV-checkpoint team" and an "outreach HCV-care team" for HCV diagnosis, assessment and DAA therapy in Chidong/Chikan villages between 2019 and 2021. Participants from neighboring villages served as Control group. RESULTS: A total of 5731 adult residents participated in the project. Anti-HCV prevalence rate was 24.0% (886/3684) in Target Group and 9.5% (194/2047) in Control group (P < 0.001). The HCV-viremic rates among anti-HCV-positive subjects were 42.7% and 41.2%, respectively, in Target and Control groups. After COMPACT engagement, 80.4% (304/378) HCV-viremic subjects in the Target group were successfully linked-to-care, and Control group (70% (56/80), P = 0.039). The rates of link-to-treatment and SVR12 were comparable between Target (100% and 97.4%, respectively) and Control (100% and 96.4%) groups. The community effectiveness was 76.4% in the COMPACT campaign, significantly higher in Target group than in Control group (78.3% versus 67.5%, P = 0.039). The community effectiveness decreased significantly during SARS Co-V2 pandemic in Control group (from 81% to 31.8%, P < 0.001), but not in Target group (80.3% vs. 71.6%, P = 0.104). CONCLUSIONS: The outreach door-by-door screen strategy with decentralized onsite treatment programs greatly improved HCV care cascade in HCV-hyperendemic areas, a model for HCV elimination in high-risk marginalized communities in SARS Co-V2 pandemic.


Assuntos
Hepatite C Crônica , Hepatite C , Síndrome Respiratória Aguda Grave , Adulto , Humanos , Hepacivirus , Antivirais/uso terapêutico , Pandemias/prevenção & controle , Hepatite C Crônica/tratamento farmacológico , Síndrome Respiratória Aguda Grave/epidemiologia , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepatite C/prevenção & controle
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