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1.
J Exp Clin Cancer Res ; 38(1): 377, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31455352

RESUMO

BACKGROUND: Cardamonin, a chalcone isolated from Alpiniae katsumadai, has anti-inflammatory and anti-tumor activities. However, the molecular mechanism by which cardamonin inhibits breast cancer progression largely remains to be determined. METHODS: CCK-8 and Hoechst 33258 staining were used to detect cell growth and apoptosis, respectively. HIF-1α driven transcription was measured by luciferase reporter assay. Glucose uptake and lactate content were detected with 2-NBDG and L-Lactate Assay Kit. Cell metabolism assays were performed on Agilent's Seahorse Bioscience XF96 Extracellular Flux Analyzer. Mitochondrial membrane potential was measured with JC-1 probe. DCFH-DA was used to measure ROS level. Protein expression was detected by western blotting assay. Immunohistochemistry was performed to measure the expression of HIF-1α, LDHA and CD31 in tumor tissues. RESULTS: Cardamonin inhibited growth of the triple negative breast cancer cell line MDA-MB-231 in vitro and in vivo by suppressing HIF-1α mediated cell metabolism. Cardamonin inhibited the expression of HIF-1α at mRNA and protein levels by repressing the mTOR/p70S6K pathway, and subsequently enhanced mitochondrial oxidative phosphorylation and induced reactive oxygen species (ROS) accumulation. We also found that cardamonin inhibited the Nrf2-dependent ROS scavenging system which further increased intracellular ROS levels. Eventually, accumulation of the intracellular ROS induced apoptosis in breast cancer cells. In addition, cardamonin treatment reduced glucose uptake as well as lactic acid production and efflux, suggesting its function in repressing the glycolysis process. CONCLUSIONS: These results reveal novel function of cardamonin in modulating cancer cell metabolism and suppressing breast cancer progression, and suggest its potential for breast cancer treatment.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31374945

RESUMO

OBJECTIVE: The China Center for Disease Control and Prevention (CDC) introduced an innovative financing model of tuberculosis (TB) care and control with the aim of standardizing TB treatment and reducing the financial burden associated with patients with TB. This is a study of the pilot implementation of new financing mechanism in Zhenjiang, between 2014-2015. We compared TB hospitalization rates and inpatient service costs before and after implementation to examine the factors associated with hospital admissions. Our goal is to provide evidence-based recommendations for improving TB service provision and cost control. METHODS: We reviewed new policy documents on TB financing. We conducted a patient survey to investigate the utilization of inpatient services, and patients' out-of-pocket payment for inpatient care. We extracted total medical expenditures of inpatient services from inpatient records of TB designated hospitals. FINDINGS: 63.6% (n = 159) of the surveyed patients with TB were admitted for treatment in 2015, which was higher than that in 2013 (54.8%, n = 144). The number of hospital admission was slightly lower in 2015 (1.16 per patient) than in 2013 (1.26 per patient), while the length of hospital stay was longer in 2015 (24 days) than in 2013 (16 days). In 2015, patients from families with low incomes were more likely to be admitted than those from higher income groups (OR = 3.06, 95% CI: 1.12-8.33). The average inpatient service cost in 2015 (3345 USD) was 1.7 times the cost in 2013 (1952 USD). It was found that 96.2% of patients with TB who were from low-income households spent more than 20% of their household income on inpatient care in 2013, versus 100% in 2015. CONCLUSION: The TB hospital admission rate and total inpatient service cost increased over the study period. The majority of patients with TB, particularly poor patient who used inpatient care, continue to suffer from heavy financial burden.

3.
Toxicology ; 426: 152256, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31381935

RESUMO

BACKGROUND: Parkinson's disease (PD) is a neurodegenerative disorder that is characterized by the degeneration of dopaminergic neurons in substantia nigra (SN). Accumulating evidences implicate the beneficial role of estrogen in the therapy of PD. METHODS: In the present study, the protective function of luteolin-7-O-glucoside (LUT-7G), a natural flavonoid, was investigated in 1-methyl-4-phenylpyridinium (MPP+) treated SH-SY5Y cells and 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) induced mice. RESULTS: Pre-treatment of LUT-7G increased the viability and reduced the apoptosis of SH-SY5Y cells treated by MPP+. At molecular level, the Bcl-2/Bax ratio was increased, while the expression of cleaved caspase 3 was markedly lessened. Moreover, LUT-7G increased the expression of estrogen receptor (ER), ERα and ERß, and enhanced the activation of ERK1/2/STAT3/c-Fos that could be abolished by ER antagonists. Furthermore, in vivo experiment indicated that pre-treatment of LUT-7G improved the bradykinesia, and enhanced the muscle strength as well as the balancing capacity of mice treated with MPTP. And LUT-7G prevented the injury of TH positive cells in substantia nigra and increased TH positive nerve fibers in striatum. In addition, pre-treatment of LUT-7G also significantly diminished the MPTP-induced gliosis in substantia nigra. CONCLUSIONS: LUT-7G effectively protected dopaminergic neurons against MPP+ or MPTP-induced toxicity, probably by activating the ER-mediated signaling pathway. Our findings explore the therapeutic potential of LUT-7G for PD therapy.

4.
Infect Dis Poverty ; 8(1): 67, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31370909

RESUMO

BACKGROUND: Tuberculosis (TB) is still a major public health problem in China. To scale up TB control, an innovative programme entitled the 'China-Gates Foundation Collaboration on TB Control in China was initiated in 2009. During the second phase of the project, a policy of increased reimbursement rates under the New Cooperative Medical Scheme (NCMS) was implemented. In this paper, we aim to explore how this reform affects the financial burden on TB patients through comparison with baseline data. METHODS: In two cross-sectional surveys, quantitative data were collected before (January 2010 to December 2012) and after (April 2014 to June 2015) the intervention in the existing NCMS routine data system. Information on all 313 TB inpatients, among which 117 inpatients in the project was collected. Qualitative data collection included 11 focus group discussions. Three main indicators, non-reimbursable expenses rate (NER), effective reimbursement rate (ERR), and out-of-pocket payment (OOP) as a percentage of per capita household income, were used to measure the impact of intervention by comprising post-intervention data with baseline data. The quantitative data were analysed by descriptive analysis and non-parametric tests (Mann-Whitney U test) using SPSS 22.0, and qualitative data were subjected to thematic framework analysis using Nvivo10. RESULTS: The nominal reimbursement rates for inpatient care were no less than 80% for services within the package. Total inpatient expenses greatly increased, with an average growth rate of 11.3%. For all TB inpatients, the ERR for inpatient care increased from 52 to 66%. Compared with inpatients outside the project, for inpatients covered by the new policy, the ERR was higher (78%), and OOP showed a sharper decline. In addition, their financial burden decreased significantly. CONCLUSIONS: Although the nominal reimbursement rates for inpatient care of TB patients greatly increased under the new reimbursement policy, inpatient OOP expenditure was still a major financial problem for patients. Limited diagnosis and treatment options in county general hospitals and inadequate implementation of the new policy resulted in higher inpatient expenditures and limited reimbursement. Comprehensive control models are needed to effectively decrease the financial burden on all TB patients.

5.
Int J Biol Macromol ; 140: 965-972, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31442503

RESUMO

This study investigated the structural characteristic and in vitro digestion and fermentation behaviours of polysaccharide from litchi pulp (LPII). The results showed that LPII was 161.24kDa, and consisted of arabinose, galactose, rhamnose and glucose. The glycosidic linkages were identified as α-L-Araf-(1→, →5)-α-Araf-(1→ and →3,6)-ß-D-Galp-(1→. After 4h gastric digestion, the molecular weight (Mw) of LPII was declined and the reducing sugars content (CR) was increased significantly. But, the intestinal digestion had no effect on the structure of LPII. In addition, after 24h gut microbiota fermentation, the neutral sugars content and pH value decreased while total bacteria amount, CR, the production of short-chain fatty acids, acetic acid and n-butyric acid increased. These results showed that LPII could be digested in gastric digestion and fermented in large intestine fermentation broth, but not changed in small intestinal fluid. The digestion and fermentation behaviours of LPII may be related with its structural features.

6.
Chem Asian J ; 2019 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-31376335

RESUMO

All-polymer solar cells (all-PSCs), with the photoactive layer exclusively composed of polymers as both donor and acceptor, have attracted growing attention due to their unique merits in optical, thermal and mechanical durability. Through the combined strategies in materials design and device engineering, recently the power conversion efficiencies of single-junction all-PSCs have been boosted up to 11 %. This review focuses on the recent progress of all-PSCs comprising of wide band-gap p-type polymers, especially those based on the units of thieno[3,4-c]pyrrole-4,6(5H)-dione], fluorinated benzotriazole, benzo[1,2-c:4,5-c']dithiophene-4,8-dione, and pyrrolo[3,4-f]benzotriazole-5,7(6H)-dione. Meantime, several categories of n-type polymers used to match with these polymer donors are also reviewed. Finally, a brief summary of the strategies of molecular design and morphology optimization is given, and strategies toward further improving performance of all-PSCs are outlined.

7.
Biosci Biotechnol Biochem ; : 1-12, 2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31282254

RESUMO

This study investigated the contents of saponins and phenolic compounds in relation to their antioxidant activity and α-glucosidase inhibition activity of 7 colored quinoa varieties. The total saponin content was significantly different among 7 varieties and ranged from 7.51 to 12.12 mg OAE/g DW. Darker quinoa had a higher content of phenolic compounds, as well as higher flavonoids and antioxidant activity than that of light varieties. Nine individual phenolic compounds were detected in free and bound form, with gallic acid and ferulic acid representing the major compounds. The free and bound phenolic compounds (gallic acid and ferulic acid in particular) exhibited high linear correlation with their corresponding antioxidant values. In addition, the free phenolic extracts from colored quinoa exhibited higher inhibitory activity against α-glucosidase than the bound phenolic extracts. These findings imply that colored quinoa with abundant bioactive phytochemicals could be an important natural source for preparing functional food.

8.
Chemosphere ; 236: 124327, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31319314

RESUMO

The egg samples of four heron species, including black-crowned night heron (Nycticorax nycticorax), little egret (Egretta garzetta), Chinese pond heron (Ardeola bacchus) and cattle egret (Bubulcus ibis), were collected from the upper Yangtze River (Changjiang) Basin, Southwest China in early summer of 2017. Nine out of ten target organophosphate flame retardants (PFRs) were detected in these heron egg samples. The sum of concentrations of the PFRs quantified (∑PFRs) ranged from 63 to 590 pmol g-1 ww (18-185 ng g-1 ww) with a median value of 139 pmol g-1 ww (48 ng g-1 ww) among all samples. The median ∑PFRs in eggs of night herons (160 pmol g-1 ww) was higher than Chinese pond herons (median 121 pmol g-1 ww) and little egrets (median 109 pmol g-1 ww). In heron eggs, ∑PFRs were mainly contributed by tri-n-butyl phosphate (TNBP), tris (isobutyl) phosphate (TIBP), tris (1-chloro-2-propyl) phosphate (TCIPP) and tri-2-methylphenyl phosphate (TMPP). Alkyl-PFRs accounted for approximately 28%-85% (median 57%) of the nine PFRs quantified while the rest is contributed by aryl-PFRs and chlorinated PFRs. Lower levels of PFRs in little egret eggs were found upstream than downstream of the Yangtze. In addition, the daily intakes of PFRs through ingestion of heron eggs were estimated at lower levels.

9.
Zhongguo Zhong Yao Za Zhi ; 44(11): 2283-2291, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31359655

RESUMO

To build up an identification method on cardiac glycosides in Taxillus chinensis and its Nerium indicum host, and evaluate the influence on medicine quality from host to T. chinensis, ultra-performance liquid chromatography coupled with quadrupole-time-of-flight tandem mass-mass spectrometry(UPLC-Q-TOF-MS/MS)was applied. The samples of T. chinensis(harvested from N. indicum)and its N. indicum host were collected in field. The samples of T. chinensis(harvested from Morus alba)and its M. alba host was taken as control substance. All samples were extracted by ultrasonic extraction in 70% ethanol. Chromatographic separation was performed on an ACQUITY UPLC HSS T3 C_(18)(2.1 mm×100 mm,1.8 µm)column at 40 ℃. Gradient elution was applied, and the mobile phase was consisted of 0.1% formic acid water and acetonitrile. The 0.5 µL of sample solution was injected and the flow rate of the mobile phase was kept at 0.6 mL·min~(-1) in each run. It was done to identify cardiac glycosides and explore the chemical composition correlation in T. chinensis and its N. indicum host by analyzing positive and negative ion mode mass spectrometry data, elemental composition, cardiac glycoside reference substance and searching related literatures. A total of 29 cardiac glycosides were identified, 28 of it belonged to N. indicum host, 5 belonged to T. chinensis(harvested from N. indicum host), none of cardiac glycoside was identified in T. chinensis(harvested from M. alba host). The result could provide a reference in evaluating the influence in T. chinensis medicine quality from host. It was rapid, accurate, and comprehensive to identify cardiac glycosides in T. chinensis and its N. indicum host by UPLC-Q-TOF-MS/MS.

10.
Cell Commun Signal ; 17(1): 85, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31349793

RESUMO

BACKGROUND: To clarify the effects of cylcin E1 expression on HCC tumor progression, we studied the expression of cyclin E1 and inhibitory efficacy of regorafenib and sorafenib in HCC cells, and investigated a potential therapy that combines regorafenib treatment with cyclin E1 inhibition. METHODS: Western blotting for caspase-3 and Hoechst 33225 staining was used to measure the expression level of apoptosis-related proteins under drug treatment. RESULTS: Our results showed that enhanced expression of cyclin E1 after transfection compromised apoptosis in HCC cells induced by regorafenib or sorafenib. Conversely, down-regulation of cyclin E1 gene expression or inhibition of cyclin E1 by the cyclin-dependent kinase (CDK) inhibitors dinaciclib (DIN) or flavopiridol sensitized HCC cells to regorafenib and sorafenib by inducing apoptosis. The expression of Mcl-1, which is modulated by STAT3, plays a key role in regulating the therapeutic effects of CDK inhibitors. Xenograft experiments conducted to test the efficacy of regorafenib combined with DIN showed dramatic tumor inhibitory effects due to induction of apoptosis. Our results suggested that the level of cyclin E1 expression in HCCs may be used as a pharmacodynamic biomarker to assess the antitumor effects of regorafenib or sorafenib. CONCLUSIONS: Combining regorafenib and CDK inhibitors may enhance the clinical efficiency of the treatment of HCCs.

11.
Trop Med Int Health ; 24(9): 1078-1087, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31299130

RESUMO

OBJECTIVE: Poor compliance with existing guidelines for tuberculosis (TB) care and treatment is an issue of concern in China. We assessed health service use by TB patients over the entire treatment process and compared it to the recommended guidelines. METHODS: We collected insurance claims data in three counties of one province of Eastern China. Patient records with a diagnosis of 'pulmonary TB' in 2015 and 2016 were extracted. Treatment duration, number of outpatient (OP) visits and hospital admissions, as well as total cost, out-of-pocket (OOP) payments and effective reimbursement rates were analysed. RESULTS: A total of 1394 patients were included in the analysis. More than 48% received over the 8 months of treatment that TB guidelines recommend, and over 28% received less. 49% of Urban and Rural Resident Basic Medical Insurance (URRBMI) TB patients were hospitalised while 30% of those with Urban Employee Basic Medical Insurance (UEBMI) had at least one admission. Median total cost for patients with hospital admission was almost 10 times that of patients without. By comparison, the average OOP was 5 times higher. UEBMI patients had a shorter treatment period, more outpatient visits but considerably fewer hospital admissions than URRBMI patients. CONCLUSIONS: We found an alarming extent of TB over- and under-treatment in our study population. There is an urgent need to improve compliance with treatment guidelines in China and to better understand the drivers of divergence. Extending the coverage of health insurance schemes and increasing reimbursement rates for TB outpatient services would seem to be key factors in reducing both the overall cost and financial burden on patients.

12.
Clin Chem Lab Med ; 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31339850

RESUMO

Background Evaluating the tumor RAS/BRAF status is important for treatment selection and prognosis assessment in metastatic colorectal cancer (mCRC) patients. Correction of artifacts from library preparation and sequencing is essential for accurately analyzing circulating tumor DNA (ctDNA) mutations. Here, we assessed the analytical and clinical performance of a novel amplicon-based next-generation sequencing (NGS) assay, Firefly™, which employs a concatemer-based error correction strategy. Methods Firefly assay targeting KRAS/NRAS/BRAF/PIK3CA was evaluated using cell-free DNA (cfDNA) reference standards and cfDNA samples from 184 mCRC patients. Plasma results were compared to the mutation status determined by ARMS-based PCR from matched tissue. Samples with a mutation abundance below the limit of detection (LOD) were retested again by droplet digital polymerase chain reaction (ddPCR) or NGS. Results The Firefly assay demonstrated superior sensitivity and specificity with a 98.89% detection rate at an allele frequency (AF) of 0.2% for 20 ng cfDNA. Generally, 40.76% and 48.37% of the patients were reported to be positive by NGS of plasma cfDNA and ARMS of FFPE tissue, respectively. The concordance rate between the two platforms was 80.11%. In the pre-treatment cohort, the concordance rate between plasma and tissue was 93.33%, based on the 17 common exons that Firefly™ and ARMS genotyped, and the positive percent agreement (PPA) and negative percent agreement (NPA) for KRAS/NRAS/BRAF/PIK3CA were 100% and 99.60%, respectively. Conclusions Total plasma cfDNA detected by Firefly offers a viable complement for mutation profiling in CRC patients, given the high agreement with matched tumor samples. Together, these data demonstrate that Firefly could be routinely applied for clinical applications in mCRC patients.

13.
Int J Nanomedicine ; 14: 4817-4831, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308660

RESUMO

Background: In vitro (1R,3S)-1-methyl-1,2,3,4-tetrahydro-ß-carboline-3-carboxyl-Lys(Pro-Ala-Lys)-Arg-Gly-Asp-Val (MTCA-KKV) adheres activated platelets, targets P-selectin and GPIIb/IIIa. This led to the development of MTCA-KKV as thrombus targeting nano-medicine. Methods: MTCA-KKV was characterized by nano-feature, anti-thrombotic activity, thrombolytic activity, thrombus target and targeting release. Results: In vivo 0.01 µmol/kg of MTCA-KKV formed nano-particles less than 100 nm in diameter, targeted thrombus, released anti-thrombotic and thrombolytic pharmacophores, prevented thrombosis and dissolved blood clots. Conclusion: Based on the profiles of targeting thrombus, targeting release, inhibiting thrombosis and dissolving blood clots MTCA-KKV is a promising nano-medicine.

14.
Cell Rep ; 28(3): 735-745.e4, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31315051

RESUMO

Activation of both the DNA damage response (DDR) and transforming growth factor ß (TGF-ß) signaling induces growth arrest of most cell types. However, it is unclear whether the DDR activates TGF-ß signaling that in turn contributes to cell growth arrest. Here, we show that in response to DNA damage, ataxia telangiectasia mutated (ATM) stabilizes the TGF-ß type II receptor (TßRII) and thus enhancement of TGF-ß signaling. Mechanistically, ATM phosphorylates and stabilizes c-Cbl, which promotes TßRII neddylation and prevents its ubiquitination-dependent degradation. Consistently, DNA damage enhances the interaction among ATM, c-Cbl, and TßRII. The ATM-c-Cbl-TßRII axis plays a pivotal role in intestinal regeneration after X-ray-induced DNA damage in mouse models. Therefore, ATM not only mediates the canonical DDR pathway but also activates TGF-ß signaling by stabilizing TßRII. The double brake system ensures full cell-cycle arrest, allowing efficient DNA damage repair and avoiding passage of the damaged genome to the daughter cells.

15.
J Med Chem ; 62(15): 7146-7159, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31256587

RESUMO

A high-throughput screen for inhibitors of the histone acetyltransferase, KAT6A, led to identification of an aryl sulfonohydrazide derivative (CTX-0124143) that inhibited KAT6A with an IC50 of 1.0 µM. Elaboration of the structure-activity relationship and medicinal chemistry optimization led to the discovery of WM-8014 (97), a highly potent inhibitor of KAT6A (IC50 = 0.008 µM). WM-8014 competes with acetyl-CoA (Ac-CoA), and X-ray crystallographic analysis demonstrated binding to the Ac-CoA binding site. Through inhibition of KAT6A activity, WM-8014 induces cellular senescence and represents a unique pharmacological tool.

16.
Arch Physiol Biochem ; : 1-7, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31291135

RESUMO

Context: Sodium glucose co-transporter 1 (SGLT1) triggers low glucose-induced glucagon-like peptide-1 (GLP-1) secretion. We reported that a two-week administration of 3-deoxyglucosone (3DG), an independent factor associated with the development of pre-diabetes, reduces basal GLP-1 secretion in rats. Objective: This study investigated the effects of 3DG on GLP-1 secretion and SGLT1 pathway under low-glucose conditions in STC-1 cells. Methods: STC-1 cells were incubated with phloridzin or 3DG at 5.6 mM glucose. SGLT1 expression (by western blotting), GLP-1 and cyclic adenosine monophosphate (cAMP) levels (by ELISA), and intracellular Ca2+ concentration (by Fluo-3/AM) were measured. Results: Phloridzin inhibited GLP-1 secretion. SGLT1 protein expression in STC-1 cells cultured in 5.6 mM glucose is higher than that in 25 mM glucose. Exposure to 3DG for 6 h reduced GLP-1 secretion, SGLT1 protein expression, and intracellular concentrations of cAMP and Ca2+. Conclusions: 3DG reduces low glucose-induced GLP-1 secretion in part through reduction of SGLT1 expression.

17.
J Gen Virol ; 100(8): 1222-1233, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31259681

RESUMO

Rabies, caused by rabies virus (RABV), is a fatal zoonosis, which still poses a threat to public health in most parts of the world. Glycoprotein of RABV is the only viral surface protein, which is critical for the induction of virus-neutralizing antibodies (VNA). In order to improve the production of VNA, recombinant RABVs containing two copies of G gene and codon-optimized G gene were constructed by using reverse genetics, named LBNSE-dG and LBNSE-dOG, respectively. After being inoculated into the mouse brains, LBNSE-dOG induced more apoptosis and recruited more inflammatory cells than LBNSE-dG and LBNSE, resulting in reduced virulence in vivo. After intramuscular (im) immunization in mice, LBNSE-dOG promoted the formation of germinal centres (GCs), the recruitment of GC B cells and the generation of antibody-secreting cells (ASCs) in the draining lymph nodes (LNs). Consistently, LBNSE-dOG boosted the production of VNA and provided better protection against lethal RABV challenge than LBNSE-dG and LBNSE when it was used as both live and inactivated vaccines. Our results demonstrate that the codon-optimized RABV LBNSE-dOG displays attenuated pathogenicity and enhanced immunogenicity, therefore it could be a potential candidate for the next generation of rabies vaccines.

18.
Am J Physiol Lung Cell Mol Physiol ; 317(3): L392-L401, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31313617

RESUMO

Here we describe a novel method for studying the protein "interactome" in primary human cells and apply this method to investigate the effect of posttranslational protein modifications (PTMs) on the protein's functions. We created a novel "biomimetic microsystem platform" (Bio-MSP) to isolate the protein complexes in primary cells by covalently attaching purified His-tagged proteins to a solid microscale support. Using this Bio-MSP, we have analyzed the interactomes of unphosphorylated and phosphomimetic end-binding protein-3 (EB3) in endothelial cells. Pathway analysis of these interactomes demonstrated the novel role of EB3 phosphorylation at serine 162 in regulating the protein's function. We showed that phosphorylation "switches" the EB3 biological network to modulate cellular processes such as cell-to-cell adhesion whereas dephosphorylation of this site promotes cell proliferation. This novel technique provides a useful tool to study the role of PTMs or single point mutations in activating distinct signal transduction networks and thereby the biological function of the protein in health and disease.

19.
Mol Biol Rep ; 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31228040

RESUMO

Maintenance of glucose homeostasis is reciprocally regulated by insulin and glucagon-like peptide-1 (GLP-1). We previously reported that GLP-1 secretion in response to an oral glucose load was impaired following an administration of 3-deoxyglucosone (3DG), an independent factor associated with the development of pre-diabetes. Here we investigated the effects of 3DG on insulin signaling and insulin-induced GLP-1 secretion under high-glucose conditions in the enteroendocrine L cell line STC-1. STC-1 cells were exposed to 3DG (80, 300, and 1000 ng/ml) in the presence of 10-7 M insulin and 25 mM glucose. GLP-1 secretion was determined by ELISA, glucose uptake was monitored with 2-NBDG (2-(N(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino)-2-deoxyglucose), glucose consumption was detected by glucoseoxidase, and protein expression of insulin signaling molecules was examined by western blot. Results showed a decrease in insulin-induced GLP-1 secretion and insulin receptor phosphorylation after 3DG treatment. Concomitantly, 3DG treatment inhibited insulin-induced phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt) pathway activation. In the presence, but not absence, of insulin, 3DG treatment decreased insulin-stimulated glucose consumption. Inhibition of PI3K with Wortmannin attenuated insulin-induced increment in glucose transporter 2 (GLUT2) expression and 2-NBDG uptake. Accordingly, insulin-induced increase in GLUT2 expression and 2-NBGD uptake was significantly inhibited by 3DG treatment. 3DG-mediated reduction in GLUT2 expression contributes to the attenuation of insulin-induced GLP-1 secretion under high-glucose conditions in part through the insulin-PI3K/Akt/GLUT2 pathway in STC-1 cells. We conclude that 3DG interferes with insulin signaling and attenuates insulin action on glucose-induced GLP-1 secretion in STC-1 cells.

20.
Plant J ; 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31168864

RESUMO

Day length or photoperiod changes are crucial for plants to align the timing of the floral transition with seasonal changes. Through the photoperiod pathway, day length changes induce the expression of the florigenic FLOWERING LOCUS T (FT) to promote flowering. In the facultative long days (LDs) plant Arabidopsis thaliana, LD signals induce flowering, whereas short days (SDs) inhibit flowering. Here, we show that in Arabidopsis SIN3 LIKE (SNL) family genes, encoding a scaffold protein for assembly of histone deacetylase complexes, directly repress the expression of an FT activator and three FT repressors to regulate the transition to flowering in SDs and LDs, respectively. Under inductive LDs, SNLs including SIN3 LIKE 1 (SNL1) to SNL5, function in partial redundancy to repress the expression of three AP2 family transcription factors that repress FT expression, and therefore mediate LD induction of FT expression and promote the transition to flowering. In contrast, under non-inductive SDs SNLs act to inhibit the floral transition, partly through direct repression of a MADS box transcriptional factor that promotes FT expression. Therefore, our results reveal that SNLs, through histone deacetylation, play a dual role for the control of flowering in the LD plant Arabidopsis: inhibiting flowering when the day length is shorter and promoting the floral transition when days become longer than a threshold length.

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