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1.
World J Diabetes ; 14(10): 1524-1531, 2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37970125

ABSTRACT

BACKGROUND: Gestational diabetes mellitus (GDM) can lead to excessive pregnancy weight gain (PWG), abnormal glucolipid metabolism, and delayed lactation. Therefore, it is necessary to provide appropriate and effective interventions for pregnant women with GDM. AIM: To clarify the effects of individualized nutrition interventions on PWG, glucolipid metabolism, and lactation in pregnant women with GDM. METHODS: The study population consisted of 410 pregnant women with GDM who received treatment at the Northern Jiangsu People's Hospital of Jiangsu Province and Yangzhou Maternal and Child Health Hospital between December 2020 and December 2022, including 200 who received routine in-terventions [control (Con) group] and 210 who received individualized nutrition interventions [research (Res) group]. Data on PWG, glucolipid metabolism [total cholesterol, (TC); triglycerides (TGs); fasting blood glucose (FPG); glycosylated hemoglobin (HbA1c)], lactation time, perinatal complications (cesarean section, premature rupture of membranes, postpartum hemorrhage, and pregnancy-induced hypertension), and neonatal adverse events (premature infants, fetal macrosomia, hypo-glycemia, and respiratory distress syndrome) were collected for comparative analysis. RESULTS: The data revealed markedly lower PWG in the Res group vs the Con group, as well as markedly reduced TG, TC, FPG and HbA1c levels after the intervention that were lower than those in the Con group. In addition, obviously earlier lactation and statistically lower incidences of perinatal complications and neonatal adverse events were observed in the Res group. CONCLUSION: Individualized nutrition interventions can reduce PWG in pregnant women with GDM, improve their glucolipid metabolism, and promote early lactation, which deserves clinical promotion.

3.
Org Lett ; 25(10): 1760-1764, 2023 03 17.
Article in English | MEDLINE | ID: mdl-36867548

ABSTRACT

Quinolizidomycins A (1) and B (2), two unprecedented quinolizidine alkaloids featuring a tricyclic 6/6/5 ring system, were isolated from Streptomyces sp. KIB-1714. Their structures were assigned by detailed spectroscopic data analyses and X-ray diffraction. Stable isotope labeling experiments suggested that compounds 1 and 2 are derived from lysine, ribose 5-phosphate, and acetate units, which indicates an unprecedented manner of assembly of the quinolizidine (1-azabicyclo[4.4.0]decane) scaffold in quinolizidomycin biosynthesis. Quinolizidomycin A (1) was active in an acetylcholinesterase inhibitory assay.


Subject(s)
Alkaloids , Streptomyces , Quinolizidine Alkaloids , Alkaloids/chemistry , Streptomyces/chemistry , Acetylcholinesterase , Molecular Structure
4.
J Nat Prod ; 86(1): 176-181, 2023 01 27.
Article in English | MEDLINE | ID: mdl-36634313

ABSTRACT

Six new azoxy-aromatic compounds (o-alkylazoxymycins A-F, 1-6) and two new nitrogen-bearing phenylvaleric/phenylheptanoic acid derivatives (o-alkylphemycins A and B, 7 and 8) were isolated from Streptomyces sp. Py50. Their structures were elucidated based on HRESIMS, NMR, UV spectroscopic analyses, and X-ray crystallographic data. O-Alkylazoxymycins A-F (1-6) are the first natural examples of azoxy compounds with the azoxy bond attached to the ortho-position of the phenylheptanoic acid or phenylvaleric acid moiety. Compounds 1, 5, and 6 were active against Epidermophyton floccosum with MIC50 values ranging from 10.1 to 51.2 µM. A plausible biosynthetic pathway of 2 and 3 was proposed.


Subject(s)
Streptomyces , Streptomyces/chemistry , Magnetic Resonance Spectroscopy , Azo Compounds/chemistry , Crystallography, X-Ray , Biosynthetic Pathways , Molecular Structure
5.
Pathog Glob Health ; 116(2): 99-106, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34029172

ABSTRACT

Information on age-based Taenia solium taeniasis prevalence is crucial for control of cysticercosis. T. solium taeniasis prevalence was determined for a village in Liangshan Prefecture, Sichuan Province, China that was co-endemic for T. solium, Taenia saginata asiatica, and Taenia saginata. Individuals who were Taenia egg-positive by stool microscopy and/or expelled tapeworms or proglottids post-treatment were diagnosed as having taeniasis. Infecting species was identified via multiplex PCR on tapeworm specimens or coproPCR followed by sequencing. In addition, initial stool samples from 10 children with taeniasis suspected of having spontaneous expulsion of tapeworms within the period between diagnosis and treatment were subject to species confirmation via coproPCR and sequencing. Of the 389 study subjects, 194 (49.9%) were diagnosed with taeniasis. Children (< 16 years of age) had a higher T. solium taeniasis prevalence (8.8%) than older individuals (2.5%) (P = 0.0127). Molecular analysis of initial stool samples from 7 of 10 children suspected of spontaneously passing tapeworms indicated 6 infections due to T. solium and 1 infection due to T. saginata. This study found that young children had a higher T. solium taeniasis prevalence than older individuals, providing additional support for the belief that adult T. solium likely has a relatively short lifespan compared to other Taenia species with human definitive hosts.


Subject(s)
Cysticercosis , Parasites , Taenia solium , Taeniasis , Adult , Animals , Child , Child, Preschool , Cysticercosis/epidemiology , Cysticercosis/parasitology , Humans , Longevity , Prevalence , Taenia solium/genetics , Taeniasis/diagnosis , Taeniasis/epidemiology , Taeniasis/parasitology
6.
Ann Palliat Med ; 10(10): 10697-10705, 2021 10.
Article in English | MEDLINE | ID: mdl-34763430

ABSTRACT

BACKGROUND: Hypoalbuminemia is a significant risk factor of cardiovascular disease and all-cause death in patients undergoing conventional hemodialysis (HD). However, the albumin (ALB) level of these dialysis patients runs through the whole process of dialysis, and the prognostic value of serum ALB in the early stage of HD and the relationship between the early ALB value and death in HD patients has not been reported. METHODS: The data of 447 patients with HD were retrospectively analyzed. The patients were stratified into three ALB (g/L) groups: low, ALB ≤34.2; moderate, 34.3< ALB <40.1; high, ALB ≥40.2. Survival trends of the three groups were analyzed by the Kaplan-Meier method. RESULTS: Comparison of the clinical data among the three groups showed a positive correlation between Hb, RBC, K+, Ca2+, Mg2+, and PHOS (P<0.05), but a negative correlation between age and high-sensitivity C-reactive protein (hsCRP) (P<0.05). The ALB level in early HD patients was an independent predictor of death [hazard ratio (HR) =0.945; 95% confidence interval (CI): 0.916-0.976; P=0.000], while age and hsCRP were protective factors (HR =1.048, 95% CI: 1.028-1.067, P=0.000; HR =1.049, 95% CI: 1.024-1.075, P=0.000). The estimated median overall survival (OS) at early HD was 56.00 months in the low ALB group, 83.00 months in the moderate ABL group, and 95.00 months in the high ALB group. The Kaplan-Meier estimate of survival showed a significant difference in OS among the three groups (log-rank P=0.000). CONCLUSIONS: The early ALB level not only reflects the nutritional and chronic inflammation status of HD patients, but can also predict the prognosis, which has guiding significance for the management of HD patients.


Subject(s)
Renal Dialysis , Serum Albumin , Humans , Kaplan-Meier Estimate , Prognosis , Proportional Hazards Models , Retrospective Studies
7.
Org Lett ; 22(20): 7930-7935, 2020 10 16.
Article in English | MEDLINE | ID: mdl-33001654

ABSTRACT

Three unprecedented cytochalasan homodimers, bisaspochalasins A-C (1-3), and two known monomers, aspochalasins B and D (4 and 5), were isolated from an endophytic Aspergillus flavipes. Bisaspochalasin A (1) contains a 13-hydroxy-3,24-dioxatricyclo[11.10.11,13.02,15]tetracos-4-one cross-linkage, representing an unprecedented carbon skeleton. Bisaspochalasins B (2) and C (3) share a thioether bridge, while 3 has a peroxy modification at C-7, which may be generated by Schenck-ene photooxygenation. Their structures, including their absolute configurations, were elucidated by HRESIMS, NMR, chemical transformation, and X-ray crystallography. Bisaspochalasin A showed inhibitory activity against human T cell proliferation with an IC50 value of 15.8 µM while maintaining low cytotoxicity to T cells.


Subject(s)
Aspergillus/chemistry , Cytochalasins/pharmacology , Cell Proliferation/drug effects , Cytochalasins/chemistry , Cytochalasins/isolation & purification , Dimerization , Humans , Magnetic Resonance Spectroscopy , Molecular Structure
8.
BMC Psychiatry ; 20(1): 369, 2020 07 14.
Article in English | MEDLINE | ID: mdl-32664880

ABSTRACT

BACKGROUND: Depression is highly prevalent among Haemodialysis (HD) patients and is known to results in a series of adverse outcomes and poor quality of life (QoL). Although cognitive behavioural therapy (CBT) has been shown to improve depressive symptoms and QoL in other chronic illness, there is uncertainty in terms of the effectiveness of CBT in HD patients with depression or depressive symptoms. METHODS: All randomised controlled trials relevant to the topic were retrieved from the following databases: CINHAL, MEDLINE, PubMed, PsycINFO and CENTRAL. The grey literature, specific journals, reference lists of included studies and trials registers website were also searched. Data was extracted or calculated from included studies that had measured depression and quality of life using valid and reliable tools -this included mean differences or standardised mean differences and 95% confidence intervals. The Cochrane risk of bias tool was used to identify the methodological quality of the included studies. RESULTS: Six RCTs were included with varying methodological quality. Meta-analysis was undertaken for 3 studies that employed the CBT versus usual care. All studies showed that the depressive symptoms significantly improved after the CBT. Furthermore, CBT was more effective than usual care (MD = - 5.28, 95%CI - 7.9 to - 2.65, P = 0.37) and counselling (MD = - 2.39, 95%CI - 3.49 to - 1.29), while less effective than sertraline (MD = 2.2, 95%CI 0.43 to 3.97) in alleviating depressive symptoms. Additionally, the CBT seems to have a beneficial effect in improving QoL when compared with usual care, while no significant difference was found in QoL score when compared CBT with sertraline. CONCLUSIONS: CBT may improve depressive symptoms and QoL in HD patients with comorbid depressive symptoms. However, more rigorous studies are needed in this field due to the small quantity and varied methodological quality in the identified studies.


Subject(s)
Cognitive Behavioral Therapy , Quality of Life , Depression/therapy , Humans , Maintenance , Renal Dialysis
9.
Int J Nurs Sci ; 6(3): 247-251, 2019 Jul 10.
Article in English | MEDLINE | ID: mdl-31508442

ABSTRACT

OBJECTIVES: Delirium is a common acute cognitive impairment syndrome among intensive care unit (ICU) patients. This study was aimed to investigate the incidence, risk factors, and cumulative risk of delirium among ICU patients. METHODS: A case-control study including clinical records of 452 patients were retrospectively analyzed. Delirium was assessed using the Confusion Assessment Method for the ICU and Richmond Agitation-Sedation Scale. RESULTS: We found that 163 out of the 452 patients (36.1%) had delirium. Multivariate analysis showed that use of sedatives, length of ICU hospitalization, and physical restraint were independent risk factors for delirium. The additive effect of all three factors resulted to an odds ratio of 30.950. CONCLUSION: The incidence of delirium remained high. Thus, nurses shall strengthen the monitoring of delirium, regularly access the patient's level of calmness, and limit the use of physical restraint.

10.
Nat Commun ; 10(1): 4036, 2019 09 06.
Article in English | MEDLINE | ID: mdl-31492848

ABSTRACT

The skeleton of tropane alkaloids is derived from ornithine-derived N-methylpyrrolinium and two malonyl-CoA units. The enzymatic mechanism that connects N-methylpyrrolinium and malonyl-CoA units remains unknown. Here, we report the characterization of three pyrrolidine ketide synthases (PYKS), AaPYKS, DsPYKS, and AbPYKS, from three different hyoscyamine- and scopolamine-producing plants. By examining the crystal structure and biochemical activity of AaPYKS, we show that the reaction mechanism involves PYKS-mediated malonyl-CoA condensation to generate a 3-oxo-glutaric acid intermediate that can undergo non-enzymatic Mannich-like condensation with N-methylpyrrolinium to yield the racemic 4-(1-methyl-2-pyrrolidinyl)-3-oxobutanoic acid. This study therefore provides a long sought-after biosynthetic mechanism to explain condensation between N-methylpyrrolinium and acetate units and, more importantly, identifies an unusual plant type III polyketide synthase that can only catalyze one round of malonyl-CoA condensation.


Subject(s)
Malonyl Coenzyme A/metabolism , Plant Proteins/metabolism , Polyketide Synthases/metabolism , Pyrroles/metabolism , Solanaceous Alkaloids/metabolism , Tropanes/metabolism , Amino Acid Sequence , Biocatalysis , Chromatography, Liquid/methods , Crystallography, X-Ray , Malonyl Coenzyme A/chemistry , Models, Chemical , Molecular Structure , Phylogeny , Plant Proteins/classification , Plant Proteins/genetics , Polyketide Synthases/chemistry , Polyketide Synthases/genetics , Pyrroles/chemistry , Sequence Homology, Amino Acid , Solanaceous Alkaloids/chemistry , Tandem Mass Spectrometry/methods , Tropanes/chemistry
11.
Pestic Biochem Physiol ; 156: 63-71, 2019 May.
Article in English | MEDLINE | ID: mdl-31027582

ABSTRACT

Phenazine-1-carboxylic acid (PCA), a secondary metabolite produced by Pseudomonas spp., exhibits a high inhibitory effect in Xanthomonas oryzae pv. oryzae (Xoo), but less inhibitory effect in Xanthomonas oryzae pv. oryzicola (Xoc), and almost no inhibitory effect in Xanthomonas campestris pv. campestris (Xcc). In our previous study, reactive oxygen species (ROS) scavenging system was reported to be involved in PCA tolerance in Xanthomonas spp. However, the PCA tolerance mechanism of Xanthomonas spp. is unclear. In the current study, we constructed a Tn5-based transposon mutant library in Xcc and four highly PCA-sensitive insertion mutants were obtained. TAIL-PCR further confirmed that the Tn5 transposon was inserted in the cytochrome c maturation (CCM) system (XC_1893, XC_1897) of these mutants. Disruption of the CCM system significantly decreased the growth, motility and tolerance of Xcc to PCA and other phenazines, such as phenazine and 1-OH-phenazine. The CCM system is responsible for the covalent attachment of the apocytochrome and heme. Disruption of the transmembrane thioredox protein (Dsb) pathway (XC_0531), an essential process for the formation of mature apocytochrome, also exhibited a decreased tolerance to PCA, suggesting that the defect of cytochrome c caused decreased tolerance of Xcc to PCA. Meanwhile, disruption of the CCM system or Dsb pathway interfered with the functions of cytochrome c proteins, causing an increased sensitivity to H2O2. Collectively, we concluded that the CCM system and Dsb pathway, regulate the tolerance of Xcc to phenazines by influencing the functions of cytochrome c. Therefore, these results provide important references for revealing the action mechanism of PCA in Xanthomonas spp.


Subject(s)
Bacterial Proteins/metabolism , Cytochromes c/metabolism , Phenazines/pharmacology , Xanthomonas campestris/drug effects , Xanthomonas campestris/metabolism , Mutation/genetics , Reactive Oxygen Species/metabolism
12.
Nat Prod Res ; 33(2): 219-225, 2019 Jan.
Article in English | MEDLINE | ID: mdl-29495881

ABSTRACT

Actinomycin Z6 (1), a new member of the actinomycin family, along with three congeners of the Z-type (Z1, Z3, Z5) actinomycins, are produced from Streptomyces sp. KIB-H714. Their structures were authenticated by comprehensive spectroscopic data interpretation. Different from all the reported Z-type actinomycins, the ß-ring of the new compound actinomycin Z6 includes an additional ring linked between the actinoyl chromophore and ß-peptidolactone. In Z3 and Z5, the L-threonine in ß-depsipeptide is replaced by the unusual 4-chlorothreonine, an amino acid rarely found in actinomycin family. All isolates were evaluated for cytotoxicity against five human tumor cell lines and for inhibitory activity against Candida albicans and Staphylococcus aureus.


Subject(s)
Anti-Infective Agents/pharmacology , Antineoplastic Agents/pharmacology , Dactinomycin/analogs & derivatives , Dactinomycin/pharmacology , Streptomyces/chemistry , Anti-Infective Agents/chemistry , Antineoplastic Agents/chemistry , Candida albicans/drug effects , Cell Line, Tumor , Dactinomycin/chemistry , Drug Evaluation, Preclinical/methods , Humans , Magnetic Resonance Spectroscopy , Molecular Structure , Oxygen/chemistry , Spectrometry, Mass, Electrospray Ionization , Staphylococcus aureus/drug effects , Structure-Activity Relationship , Threonine/analogs & derivatives , Threonine/chemistry
13.
Org Biomol Chem ; 17(3): 477-481, 2019 01 16.
Article in English | MEDLINE | ID: mdl-30565634

ABSTRACT

Toxoflavin (1), fervenulin (2), and reumycin (3), known to be produced by plant pathogen Burkholderia glumae BGR1, are structurally related 7-azapteridine antibiotics. Previous biosynthetic studies revealed that N-methyltransferase ToxA from B. glumae BGR1 catalyzed the sequential methylation at N6 and N1 in pyrimido[5,4-e]-as-triazine-5,7(6H,8H)-dione (4) to generate 1. However, the N8 methylation of 4 in the biosynthesis of fervenulin remains unclear. To explore the N-methyltransferases required for the biosynthesis of 1 and 2, we identified and characterized the fervenulin and toxoflavin biosynthetic gene clusters in S. hiroshimensis ATCC53615. On the basis of the structures of intermediates accumulated from the four N-methyltransferase gene inactivation mutants and systematic enzymatic methylation reactions, the tailoring steps for the methylation order in the biosynthesis of 1 and 2 were proposed. The N-methylation order and routes for the biosynthesis of fervenulin and toxoflavin in S. hiroshimensis are more complex and represent an obvious departure from those in B. glumae BGR1.


Subject(s)
Methyltransferases/metabolism , Pyrimidinones/metabolism , Streptomyces/metabolism , Triazines/metabolism , Biocatalysis , Dose-Response Relationship, Drug , Methyltransferases/chemistry , Molecular Structure , Pyrimidinones/chemistry , Streptomyces/chemistry , Streptomyces/enzymology , Structure-Activity Relationship , Triazines/chemistry
14.
J Antibiot (Tokyo) ; 71(12): 1040-1043, 2018 11.
Article in English | MEDLINE | ID: mdl-30218038

ABSTRACT

Chemical investigation of a strain Streptomyces sp. KIB-H1318 isolated from soil sample led to the discovery of three new phenoxazinone-related alkaloids 1-3, as well as two known analogs exfoliazone (4) and viridobrunnine A (5). Their structures were determined on the basis of extensive spectroscopic analysis. The antimicrobial activity and cytotoxicity of the isolates were assayed. Exfoliazone and viridobrunnine A exhibited minor antibacterial activity against Escherichia coli ATCC 8099, Bacillus subtilis ATCC 6633, and Staphylococcus aureus ATCC 6538. Compound 2 exhibited low cytotoxicity against two human cancer cell lines HeLa and SW480 with the IC50 values of 36.8 and 37.8 µM, respectively.


Subject(s)
Alkaloids/chemistry , Oxazines/chemistry , Streptomyces/chemistry , Alkaloids/isolation & purification , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Bacillus subtilis/drug effects , Cell Line, Tumor , Escherichia coli/drug effects , Humans , Microbial Sensitivity Tests , Oxazines/isolation & purification , Staphylococcus aureus/drug effects
15.
J Antibiot (Tokyo) ; 71(7): 672-676, 2018 07.
Article in English | MEDLINE | ID: mdl-29651143

ABSTRACT

Two new glycosylated piericidins, glucopiericidinol A3 (1) and 7-demethyl-glucopiericidin A (2), along with four known analogs were isolated from the culture broth of Streptomyces sp. KIB-H1083. The chemical structures of new compounds were elucidated by spectroscopic analyses. Their cytotoxicity on HL-60, SMMC-772, A-549, MCF-7, and SW480 cell lines, as well as antimicrobial activities was evaluated. The results showed that glucopiericidin A (4) has potent cytotoxicity against HL-60, SMMC-772, A-549, and MCF-7 cell lines with IC50 values of 0.34, 0.65, 0.60, and 0.50 µM, respectively. For the antimicrobial activity, piericidin A (6) showed most powerful inhibitory activities against Xanthomonas oryzae pv. oryzicola, and Penicillium decumbens.


Subject(s)
Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Streptomyces/chemistry , Antibiotics, Antineoplastic/isolation & purification , Antibiotics, Antineoplastic/pharmacology , Antifungal Agents/isolation & purification , Antifungal Agents/pharmacology , Cell Line, Tumor , Endophytes/chemistry , Fermentation , Humans , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Penicillium/drug effects , Xanthomonas/drug effects
16.
Pestic Biochem Physiol ; 145: 8-14, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29482735

ABSTRACT

Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial leaf blight (BLB) and can be effectively controlled by phenazine-1-carboxylic acid (PCA), an antibiotic secreted by Pseudomonas spp. PCA resistance in Xoo was investigated in this research. Only four PCA-resistant strains were obtained by extensive screening, and the resistance was genetically stable in only one of them (P4). P4 was also resistant to phenazine and 1-hydroxyphezine but not to captan, bismerthiazol, or streptomycin. The following were reduced in P4 relative to the parental wild type: growth, virulence, EPS production, extracellular cellulase production and activity, biofilm formation, and swimming ability. ROS accumulation was reduced, resistance to exogenous H2O2 was increased, and expression of catalase genes and catalase activities were increased in P4, suggesting that PCA resistance in P4 results from a reduction in ROS production and/or an increased ability to metabolize ROS following PCA treatment. Given the low risk of Xoo developing PCA resistance and the reduced virulence and fitness of the resistant strain, PCA can be used in alternation with other common bactericides to control BLB in rice fields.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial , Xanthomonas/drug effects , Biofilms , Captan/pharmacology , Catalase/genetics , Catalase/metabolism , Cellulase/biosynthesis , Oryza/microbiology , Phenazines/metabolism , Phenazines/pharmacology , Plant Diseases/microbiology , Plant Diseases/prevention & control , Pseudomonas/metabolism , RNA, Messenger/genetics , Reactive Oxygen Species/metabolism , Streptomycin/pharmacology , Sulfhydryl Compounds/pharmacology , Thiadiazoles/pharmacology , Nicotiana/drug effects , Virulence , Xanthomonas/isolation & purification , Xanthomonas/metabolism , Xanthomonas/pathogenicity
17.
J Nat Prod ; 80(10): 2615-2619, 2017 10 27.
Article in English | MEDLINE | ID: mdl-28990780

ABSTRACT

Our natural products discovery program utilizes endophytic actinomycetes associated with plants and employs biological assays and HPLC-based metabolite profiles as the preliminary screen to identify strains of interest, followed by large-scale fermentation and isolation, leading to new and/or bioactive natural products. Six new trialkyl-substituted aromatic acids, namely, lorneic acids E-J (1-6), together with two known analogues (7 and 8), were isolated and identified from the culture extract of Streptomyces sp. KIB-H1289, an endophytic actinomycete obtained from the inner tissue of the bark of Betula mandshurica Nakai. The structures were characterized by interpretation of their spectroscopic data, mainly 1D and 2D NMR. Among them, compound 5 contains a unique disulfide bond that is presumably derived from N-acetylcysteine. All isolated metabolites were evaluated for their inhibitory activity on tyrosinase.


Subject(s)
Actinobacteria/chemistry , Benzene Derivatives/isolation & purification , Acetylcysteine/metabolism , Benzene Derivatives/chemistry , Betula/microbiology , Biological Products/chemistry , Biological Products/isolation & purification , Chromatography, High Pressure Liquid , Endophytes/chemistry , Molecular Structure , Monophenol Monooxygenase/antagonists & inhibitors , Nuclear Magnetic Resonance, Biomolecular , Plant Bark/chemistry , Streptomyces/chemistry
18.
Org Lett ; 19(14): 3911-3914, 2017 07 21.
Article in English | MEDLINE | ID: mdl-28703597

ABSTRACT

Euphordraculoates A (1) and B (2), featuring tigliane diterpenoids with two new carbon skeletons, were characterized as metabolites of Euphorbia dracunculoides and semisynthetic products, respectively. Their structures were determined by spectroscopic analyses and X-ray crystallography. The respective biosynthetic and chemical formation mechanisms for 1 and 2 from a known tigliane 3 was proposed. The detailed decarbonization mechanism from 3 to 2 was further explored by 18O-labeling experiment. Compound 2 could inhibit Wnt pathway in a dose- and time-dependent manner.


Subject(s)
Euphorbia/chemistry , Carbon , Diterpenes , Molecular Structure , Oxygen Isotopes , Wnt Signaling Pathway
19.
Nat Prod Bioprospect ; 7(4): 329-334, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28634711

ABSTRACT

Tamoxifen resistance (TamR) is the underlying cause of treatment failure in many breast cancer patients receiving tamoxifen. In order to look for noncytotoxic natural products with the ability to reverse TamR, an extract from strain Streptomyces sp. KIB-H0495 was detected to be active. Subsequent large scale fermentation and isolation led to the isolation of four α-pyrone derivatives including two new compounds, violapyrones J (2) and K (3), and two known analogues, violapyrones B (1) and I (4). Further bioactivity assays indicated that only 1 and 3 exerted potent resensitization effects on MCF-7/TamR cells at a concentration of 1 µM. Owing to the simple structures of 1 and 3, these two compounds might have potential for further investigation as novel tamoxifen resensitization agent in breast cancer chemotherapy.

20.
Cell Physiol Biochem ; 40(3-4): 527-537, 2016.
Article in English | MEDLINE | ID: mdl-27889763

ABSTRACT

BACKGROUND/AIMS: The present study aimed to investigate the effects of the JAK2/STAT3/SOSC1 signaling pathway on the secretion function of vascular endothelial cells (VECs) in a rat model of pregnancy-induced hypertension (PIH). METHODS: A PIH rat model was established. Forty-eight pregnant Sprague-Dawley female rats were selected and assigned into four groups: the normal group (normal non-pregnant rats), the non-PIH group (pregnant rats without PIH), the PIH group (pregnant rats with PIH) and the AG490 group (pregnant rats with PIH treated with AG490). Systolic blood pressure (SBP) and urinary protein (UP) were measured. The expressions of JAK2/STAT3/SOSC1 signaling pathway-related proteins in placenta tissues were detect by Western blotting. Radioimmunoassay was applied to detect serum levels of nitric oxide (NO), super oxide dismutase (SOD), placental growth factor (PGF), thromboxane B2 (TXB2) and endothelin (ET). Enzyme-linked immunosorbent assay (ELISA) was used to determine serum levels of interleukin-6 (IL-6), interleukin-10 (IL-10) and tumor necrosis factor-α (TNF-α). RESULTS: Compared with the normal and non-PIH groups, the PIH and AG490 groups had higher SBP and UP levels at 17th and 25th day of pregnancy. The expressions of p/t-JAK2, p/t-STAT3 and SOSC1 in the PIH and AG490 groups were higher than those in the non-PIH group, while the expressions of p/t-JAK2, p/t-STAT3 and SOSC1 in the AG490 group were lower than those in the PIH group. Compared with the non-PIH group, serum levels of ET, TXB2, IL-6 and TNF-α were increased in the PIH and AG490 groups, while serum levels of NO, SOD, 6-keto-PGF1a and IL-10 levels were reduced. Furthermore, the AG490 had lower serum levels of ET, TXB2, IL-6 and TNF-α and higher serum levels of NO, SOD, 6-keto-PGF1a and IL-10 than those in the PIH group. CONCLUSION: Our study provides evidence that inhibition of the JAK2/STAT3/SOSC1 signaling pathway could improve the secretion function of VECs in PIH rats.


Subject(s)
Endothelial Cells/metabolism , Hypertension, Pregnancy-Induced/metabolism , Janus Kinase 2/metabolism , STAT3 Transcription Factor/metabolism , Signal Transduction , Suppressor of Cytokine Signaling 1 Protein/metabolism , Animals , Blood Pressure/drug effects , Disease Models, Animal , Endothelial Cells/drug effects , Female , Fetus/drug effects , Fetus/pathology , Hypertension, Pregnancy-Induced/physiopathology , Kidney/pathology , Kidney/physiopathology , Kidney/ultrastructure , Male , Placenta/drug effects , Placenta/pathology , Pregnancy , Proteinuria/complications , Proteinuria/physiopathology , Rats, Sprague-Dawley , Signal Transduction/drug effects , Systole/drug effects , Tyrphostins/pharmacology
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