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1.
J Antibiot (Tokyo) ; 77(4): 221-227, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38228780

RESUMO

Vicenistatin (1) is a 20-membered polyketide macrocyclic antibiotic with potent antimicrobial and cytotoxic activities. In this study, to further explore the potential of 1 as candidates of antibacterial drug development, 4'-N-demethyl vicenistatin (2), a secondary metabolite obtained from the ∆vicG mutant strain of Monodonata labio-associated Streptomyces parvus SCSIO Mla-L010, was utilized as a starting material for modifications of 4'-amino group of vicenistatin. Six new vicenistatin derivatives (3-8) were semi-synthesized through a concise route of amino modification with various aliphatic and aromatic aldehydes. Our study reveals that the bioactivity of vicenistatin is closely related to amino modification in sugar moiety, which results from the length of alkyl side chain as well as the presence of electron withdrawing/denoting group on the benzene ring. Importantly, compounds 4 with a butyl group and 8 with a 3,5-dihydroxyl-benzyl group at 4'-amino group, respectively, exhibited good antimicrobial activities, with MIC values spanning 0.5-4 µg ml-1 to Gram-positive pathogens, including methicillin-resistant Staphylococcus aureus, methicillin-resistant Staphylococcus epidermidis, Micrococcus luteus and Bacillus subtilis, with low cytotoxicity. This research promotes the further exploration of structure-activity relationships of vicenistatin and provides new vicenistatin derivatives for development of future anti-infectious agents with reduced cytotoxicity.


Assuntos
Aminoglicosídeos , Anti-Infecciosos , Lactamas , Macrolídeos , Staphylococcus aureus Resistente à Meticilina , Antibacterianos/farmacologia , Relação Estrutura-Atividade , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana
2.
Front Public Health ; 11: 1182127, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37670835

RESUMO

Introduction: Although several studies have explored the associations between single essential metals and serum uric acid (SUA), the study about the essential metal mixture and the interactions of metals for hyperuricemia remains unclear. Methods: We performed a cross-sectional study to explore the association of the SUA levels with the blood essential metal mixture, including magnesium (Mg), calcium (Ca), iron (Fe), copper (Cu), zinc (Zn), manganese (Mn) in Chinese community-dwelling adults (n=1039). The multivariable linear regression, the weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) were conducted to estimate the associations of blood essential metals with SUA levels and the BKMR model was also conducted to estimate the interactions of the essential metals on SUA. Results: In the multivariable linear regression, the association of blood Mg, Mn, and Cu with SUA was statistically significant, both in considering multiple metals and a single metal. In WQS regression [ß=13.59 (95%CI: 5.57, 21.60)] and BKMR models, a positive association was found between the mixture of essential metals in blood and SUA. Specifically, blood Mg and Cu showed a positive association with SUA, while blood Mn showed a negative association. Additionally, no interactions between individual metals on SUA were observed. Discussion: In conclusion, further attention should be paid to the relationship between the mixture of essential metals in blood and SUA. However, more studies are needed to confirm these findings.


Assuntos
Ácido Úrico , Zinco , Estudos Transversais , Teorema de Bayes , Cobre
3.
Zygote ; 31(5): 498-506, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37485669

RESUMO

Placental trophoblastic cells play important roles in placental development and fetal health. However, the mechanism of trophoblastic cell fusion is still not entirely clear. The level of Tspan5 in the embryo culture medium was detected using enzyme-linked immunosorbent assay (ELISA). Fusion of BeWo cells was observed by immunofluorescence. Cell fusion-related factors and EMT-related factors were identified by qRT-PCR and western blotting. Notch protein repressor DAPT was used to verify the role of Tspan5 in BeWo cells. The expression of Tspan5 was significantly increased in embryo culture medium. The fusion of BeWo cells was observed after treatment with forskolin (FSK). Cell fusion-related factors (i.e. ß-hCG and syncytin 1/2) and Tspan5 were significantly increased after FSK treatment. In addition, FSK treatment promoted EMT-related protein expression in BeWo cells. Knockdown of Tspan5 inhibited cell fusion and EMT-related protein levels. Notch-1 and Jagged-1 protein levels were significantly upregulated, and the EMT process was activated by overexpression of Tspan5 in FSK-treated BeWo cells. Interestingly, blocking the Notch pathway by the repressor DAPT had the opposite results. These results indicated that Tspan5 could promote the EMT process by activating the Notch pathway, thereby causing cell fusion. These findings contribute to a better understanding of trophoblast cell syncytialization and embryonic development. Tspan5 may be used as a therapeutic target for normal placental development.


Assuntos
Inibidores da Agregação Plaquetária , Trofoblastos , Humanos , Feminino , Gravidez , Inibidores da Agregação Plaquetária/metabolismo , Linhagem Celular Tumoral , Placenta , Transdução de Sinais , Colforsina/metabolismo , Colforsina/farmacologia , Fusão Celular/métodos
4.
Nat Prod Res ; : 1-8, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37267595

RESUMO

Hypoxylon vinosopulvinatum DYR-1-7 is a endophytic fungus isolated from the Cinnamomum cassia Presl and has an inhibitory effect on Lasiodiplodia pseudotheobromae. Three new furanones, hypoxylonone A-C (1-3), as well as three known compounds (4-6), were isolated from an EtOAc extract of H. vinosopulvinatum DYR-1-7. The structures were determined by spectroscopic data analysis using UV, IR, 1D-, 2D-NMR and HR-ESI-MS. The absolute configurations of 1-3 were elucidated by electronic circular dichroism (ECD) analyses. In the antifungal bioassay, Hypoxylonone B and C exhibited strong inhibitory effects on L. pseudotheobromae with IC50 value at the concentration of 1.01 and 2.40 µg/mL, respectively. Compound 6 showed medium antifungal activity with IC50 value at the concentration of 10.67 µg/mL on Fusarium oxysporum. Compounds 3 and 4 displayed medium antifungul effects on Candida albicans.

5.
Front Nutr ; 10: 1129169, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37125027

RESUMO

Background: Although several studies have examined the relationships between lead (Pb) exposure and serum lipid profiles, the associations of the metal mixture, including lead (Pb) and essential metals with lipid profiles, remain unclear. Objective: To investigate the associations of the metal mixture including Pb and essential metals [magnesium (Mg), manganese (Mn), copper (Cu), iron (Fe), zinc (Zn), and calcium (Ca)] with serum lipid profiles [total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C)], as well as the potential interactions among the metals. Methods: Nine hundred and ninety-eight Chinese community-dwelling adults completed a questionnaire and underwent checkups of anthropometric parameters, serum lipid profile levels (TC, TG, LDL-C, and HDL-C), and blood metal concentrations (Pb, Mg, Mn, Cu, Fe, Zn, and Ca). The multivariable linear regression, weighted quantile sum (WQS) regression, and Bayesian kernel machine regression (BKMR) were applied to evaluate the single and combined associations of blood Pb and essential metals with serum lipid profiles. Results: In the multivariable linear regression model, the blood Pb was positively associated with TC, LDL-C, and HDL-C (p < 0.05, all), and the blood Mg were positively associated with serum TC, LDL-C, and Ln TG (p < 0.05, all). In the WQS regression and BKMR models, the metal mixture of blood Pb and the essential metals was positively associated with all of the serum lipid profiles. In addition, an inverse U-shaped association of Pb with Ln TG and the positive interactive effect between blood Pb and Mg levels on TC and LDL-C were found. Conclusion: The levels of blood Pb, together with the essential metals, especially Mg levels, are suggested to be considered when assessing dyslipidemia risk. However, more evidence is still needed to validate the conclusions.

6.
BMC Med ; 21(1): 192, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37226271

RESUMO

BACKGROUND: Both low-carbohydrate (LC) and calorie-restricted (CR) diets have been shown to have metabolic benefits. However, the two regimens have yet to be thoroughly compared. We conducted a 12-week randomized trial to compare the effects of these diets separately and in combination on both weight loss and metabolic risk factors in overweight/obese individuals. METHODS: A total of 302 participants were randomized to LC diet (n = 76), CR diet (n = 75), LC + CR diet (n = 76), or normal control (NC) diet (n = 75) using a computer-based random number generator. The primary outcome was the change in body mass index (BMI). The secondary outcomes included body weight, waist circumference, waist-to-hip ratio, body fat, and metabolic risk factors. All participants attended health education sessions during the trial. RESULTS: A total of 298 participants were analyzed. BMI change over 12 weeks was - 0.6 (95% CI, - 0.8 to - 0.3) kg/m2 in NC, - 1.3 (95% CI, - 1.5 to - 1.1) kg/m2 in CR, - 2.3 (95% CI, - 2.6 to - 2.1) kg/m2 in LC, and - 2.9 (95% CI, - 3.2 to - 2.6) kg/m2 in LC + CR. LC + CR diet was more effective than LC or CR diet alone at reducing BMI (P = 0.001 and P < 0.001, respectively). Furthermore, compared with the CR diet, the LC + CR diet and LC diet further reduced body weight, waist circumference, and body fat. Serum triglycerides were significantly reduced in the LC + CR diet group compared with the LC or CR diet alone. Plasma glucose, homeostasis model assessment of insulin resistance, and cholesterol concentrations (total, LDL, and HDL) did not change significantly between the groups during the 12-week intervention. CONCLUSIONS: The reduction of carbohydrate intake without restricting caloric intake is more potent to achieve weight loss over 12 weeks when compared to a calorie-restricted diet in overweight/obese adults. The combination of restricting carbohydrate and total calorie intake may augment the beneficial effects of reducing BMI, body weight, and metabolic risk factors among overweight/obese individuals. TRIAL REGISTRATION: The study was approved by the institutional review board of Zhujiang Hospital of Southern Medical University and registered at the China Clinical Trial Registration Center (registration number: ChiCTR1800015156).


Assuntos
Carboidratos da Dieta , Sobrepeso , Adulto , Humanos , Restrição Calórica , Obesidade , Dieta com Restrição de Carboidratos
7.
Front Endocrinol (Lausanne) ; 14: 1134208, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37051196

RESUMO

Introduction: Thyroid function has a large impact on humans' metabolism and is affected by iodine levels, but there is a scarcity of studies that elucidate the association between thyroid function and other elements. Methods: We performed a cross-sectional study on 1,067 adults to evaluate the associations of the common essential metals with thyroid function in adults living in an iodine-adequate area of China. Serum free thyroxine (FT4), free triiodothyronine (FT3), thyroid stimulating hormone (TSH), and blood metals (zinc, iron, copper, magnesium, manganese, and calcium) were measured. Further, the thyroid hormone sensitivity indexes, FT3:FT4 ratio, and thyrotropin T4 resistance index (TT4RI) were calculated. Linear regression, quantile g-computation, and Bayesian kernel machine regression methods were used to explore the association of metals with thyroid function. Results: We found that the TSH levels correlated with copper (negative) and zinc (positive). Iron and copper were positively associated with FT3 and FT4 levels, respectively. Iron (positive) and copper (negative) were correlated with the FT3:FT4 ratio. Furthermore, we found that manganese was inversely correlated with TT4RI, while zinc was positively correlated. Discussion: Our findings suggest that manganese, iron, copper, and zinc levels were strongly correlated with thyroid function, and patients with thyroid disorders are recommended to measure those metals levels.


Assuntos
Iodo , Síndrome da Resistência aos Hormônios Tireóideos , Humanos , Adulto , Tiroxina , Estudos Transversais , Cobre , Manganês , Teorema de Bayes , Hormônios Tireóideos , Tireotropina , Ferro , Zinco
8.
J Clin Endocrinol Metab ; 108(9): e687-e697, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-36999544

RESUMO

CONTEXT: Impaired sensitivity to thyroid hormones has been demonstrated to be positively associated with the prevalence of metabolic disorders. However, the relationship between sensitivity to thyroid hormones and metabolic dysfunction-associated fatty liver disease (MAFLD) and liver fibrosis remained unclear. OBJECTIVE: We aimed to determine the associations of thyroid hormone sensitivity indices with MAFLD and its progression to liver fibrosis in Chinese euthyroid adults. METHODS: This community-based study included 7906 euthyroid adults. We calculated the thyroid sensitivity indices, including free triiodothyronine to free thyroxine (FT3/FT4) ratio, Thyroid Feedback Quantile-based Index by FT4 (TFQIFT4), and Thyroid Feedback Quantile-based Index by FT3 (TFQIFT3), indicating peripheral and central thyroid hormone sensitivity respectively. Liver steatosis and fibrosis were diagnosed by vibration-controlled transient elastography (VCTE). Multivariable logistic/linear regression and restricted cubic spline (RCS) analysis were conducted. RESULTS: Compared with participants in the first quartile (Q1), the prevalence of MAFLD was increased by 62% in the fourth quartile (Q4) of FT3/FT4 ratio (OR 1.62; 95% CI [1.38, 1.91]) and by 40% in Q4 of TFQIFT3 (OR 1.40; 95% CI [1.18, 1.65]) (both P < .05). No associations between TFQIFT4 and the prevalence of MAFLD were found. In addition, compared with participants in Q1, the prevalence of liver fibrosis was increased by 45% in Q4 of TFQIFT3 (OR 1.45; 95% CI [1.03, 2.06]) (P < .05) in participants with MAFLD. CONCLUSION: Impaired central sensitivity to FT3 was associated with MAFLD and its progression to liver fibrosis. More prospective and mechanism studies are warranted to confirm these conclusions.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Tri-Iodotironina , Adulto , Humanos , Estudos Prospectivos , Fatores de Risco , Hormônios Tireóideos , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Cirrose Hepática/epidemiologia , Cirrose Hepática/etiologia , Tiroxina , Tireotropina
9.
Environ Sci Pollut Res Int ; 30(8): 21072-21080, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36264466

RESUMO

Autoimmune thyroiditis (AIT) is increasingly common, and serological markers include thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb). To determine if selected metals influence thyroiditis antibody positivity, this cross-sectional study investigated associations between metals and thyroiditis antibody status. Healthy individuals (n = 1104) completed a questionnaire and underwent checkups of anthropometric parameters, thyroid function status, and levels of seven metals in blood (magnesium, iron, calcium, copper, zinc, manganese, and lead). Associated profiles of glyco- and lipid metabolism were also established. Logistic regression and restricted cubic spline (RCS) regression analysis were applied to adjudge associations between metals and TPOAb and TgAb status. It was found that, after adjusting for likely cofounding factors, participants with antibody positivity had significantly lower serum concentrations of magnesium and iron. When serum magnesium levels were analyzed in quartiles, the odds ratios of quartile 4 were 0.329-fold (95% confidence interval (CI): 0.167-0647) and 0.259-fold (95% CI 0.177-0.574) that of quartile 1 regarding TPOAb and TgAb positivity (P = 0.004, 0.003). After adjustment, the RCS analysis detected nonlinear associations between iron and TPOAb and TgAb positivity (P < 0.01, both). In stratified analyses, these associations regarding magnesium and iron remained for women of reproductive age, but not for postmenopausal women and men. We conclude that lower serum levels of magnesium and iron are associated with incremental positivity of thyroiditis antibodies and may be among the most important metals contributing to AIT in women of reproductive age.


Assuntos
Tireoglobulina , Tireoidite Autoimune , Masculino , Humanos , Feminino , Estudos Transversais , Magnésio , Iodeto Peroxidase , Ferro
10.
Front Nutr ; 9: 1059675, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36483930

RESUMO

Objective: Although phthalates are common environmental pollutants, few studies have focused on the relationship of phthalates exposure with non-alcoholic fatty liver disease (NAFLD) or liver fibrosis, and especially, the alternative phthalates have been questioned in recent years about whether they are better choices. Thus, this study aimed to explore the associations of exposure to major phthalates or alternative phthalates with NAFLD and liver fibrosis. Methods: Data of 1450 adults from the National Health and Nutrition Examination Survey (NHANES) 2017-2018 were collected. The urinary metabolite concentrations of di-2-ethylhexyl phthalate (DEHP), diisononyl phthalate (DINP) and diisodecyl phthalate (DIDP) were detected. Controlled attenuation parameter (CAP) and median liver stiffness measurement (LSM) were acquired for quantitative diagnosis of NAFLD and liver fibrosis by vibration-controlled transient elastography. Multivariate logistic regression analysis and linear regression analysis were performed to examine the associations between phthalates and NAFLD and liver fibrosis. Results: After adjustment of the potential factors, the prevalence of NAFLD was significantly elevated among those in the fourth quartile of mono-(2-ethyl-5-carboxypentyl) phthalate (OR, 95%CI = 2.719, 1.296, 5.700, P = 0.016), mono (2-ethyl-5-hydroxyhexyl) phthalate (OR, 95%CI = 2.073, 1.111, 3.867, P = 0.037). No significant association was found between the alternative phthalates and NAFLD. The similar result was gained by linear regression analysis that MECPP was still significantly associated with Ln CAP (Q4 vs. Q1: ß, 95%CI = 0.067, 0.017, 0.118, P = 0.027). After adjustment for the same covariates, no significant association between phthalates and liver fibrosis was found in logistics regression analysis. Conclusions: All in all, higher prevalence of NAFLD is correlated with DEHP but not DINP or DIDP in American adults. There is no significant relationship between phthalates and liver fibrosis defined as LSM ≥ 8 Kpa. Nevertheless, further research is needed to provide evidence of causality.

11.
Nat Med ; 28(5): 974-981, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35551292

RESUMO

Metformin, the first-line therapy for type 2 diabetes (T2D), decreases hepatic glucose production and reduces fasting plasma glucose levels. Dorzagliatin, a dual-acting orally bioavailable glucokinase activator targeting both the pancreas and liver glucokinase, decreases postprandial glucose in patients with T2D. In this randomized, double-blind, placebo-controlled phase 3 trial, the efficacy and safety of dorzagliatin as an add-on therapy to metformin were assessed in patients with T2D who had inadequate glycemic control using metformin alone. Eligible patients with T2D (n = 767) were randomly assigned to receive dorzagliatin or placebo (1:1 ratio) as an add-on to metformin (1,500 mg per day) for 24 weeks of double-blind treatment, followed by 28 weeks of open-label treatment with dorzagliatin for all patients. The primary efficacy endpoint was the change in glycated hemoglobin (HbA1c) levels from baseline to week 24, and safety was assessed throughout the trial. At week 24, the least-squares mean change from baseline in HbA1c (95% confidence interval (CI)) was -1.02% (-1.11, -0.93) in the dorzagliatin group and -0.36% (-0.45, -0.26) in the placebo group (estimated treatment difference, -0.66%; 95% CI: -0.79, -0.53; P < 0.0001). The incidence of adverse events was similar between groups. There were no severe hypoglycemia events or drug-related serious adverse events in the dorzagliatin and metformin combined therapy group. In patients with T2D who experienced inadequate glycemic control with metformin alone, dorzagliatin resulted in effective glycemic control with good tolerability and safety profile ( NCT03141073 ).


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Glicemia , Método Duplo-Cego , Quimioterapia Combinada , Glucoquinase , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/uso terapêutico , Humanos , Hipoglicemiantes/efeitos adversos , Pirazóis , Resultado do Tratamento
12.
Front Nutr ; 9: 870873, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571937

RESUMO

Background: The association between occurrence of thyroid nodules (TNs) and trace elements detectable in blood are still inconclusive. The present study sought to determine the relationship between selected trace elements and TNs in the iodine-adequate area of Guangdong, China. Methods: A total of 1,048 participants from four communities were enrolled. A number of medical checkups were conducted to collect relevant data on anthropometric parameters, blood pressure, glucose blood levels and lipid profiles, as well as data on thyroid function, presence of thyroid autoantibodies, and trace elements. Presence of TN was diagnosed by ultrasonography. Results: Of the 1048 participants (49.5 ± 14.4 years old), 543 participants (51.8%) had TNs. Serum copper, magnesium and zinc levels are associated with the presence of TNs among healthy subjects. Subjects with higher levels of zinc, magnesium and copper had 1.23-fold, 1.04-fold, and 1.007-fold increased risks of the prevalence of TNs (P = 0.013, 0.017, and < 0.001, resp). Compared with the first quartile of copper content in serum, participants in the fourth quartile had the highest prevalence of TNs with an odds ratio of 8.90 (95% confidence interval (CI) 5.41, 14.94) among all participants. Women in the third quartile of magnesium level had a 1.86-fold (95%CI 1.05, 3.31) risk of the prevalence of TNs. Subjects in the highest quartile of zinc level had a 1.82-fold (95%CI 1.06, 3.16) risk of the prevalence of TNs in females. Conclusion: TNs were found highly prevalent in females in the investigated population from an iodine-adequate area of Guangdong, China. The imbalance of selected trace elements (copper, magnesium and zinc) in the body is related to the presence of TNs among healthy subjects. The observed correlation of copper on TNs warrants further studies.

13.
Nat Prod Res ; 35(13): 2178-2183, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31537113

RESUMO

(+)- and (-)-Spongiterpene [(+)-1 and (-)-1], a pair of new valerenane sesquiterpene enantiomers, along with four known compounds (2-5) were isolated from the marine sponge Spongia sp. The structures of (+)-1 and (-)-1 including absolute configurations were determined by spectroscopic analysis, quantum chemical calculation and X-ray diffraction. Compounds (+)-1 and (-)-1 were the first examples of valerenane sesquiterpenes isolated from the marine sponges. The cytotoxic activities of (+)-1 and (-)-1 were also evaluated.


Assuntos
Organismos Aquáticos/química , Poríferos/química , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Estereoisomerismo , Difração de Raios X
14.
Nat Prod Res ; 35(21): 3824-3829, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32202133

RESUMO

Two new pyrrolidine alkaloids, acanthophoraines B (1) and C (2), together with five known ones (3-7) were isolated from the red alga Acanthophora spicifera. Their structures were elucidated by extensive spectroscopic methods and single-crystal X-ray diffraction analysis. The absolute configuration of 2 was established by ECD calculation. The antibacterial activities of 1-7 were also evaluated.


Assuntos
Alcaloides , Anti-Infecciosos , Rodófitas , Alcaloides/farmacologia , Antibacterianos/farmacologia , Cristalografia por Raios X , Estrutura Molecular , Pirrolidinas/farmacologia
15.
Aging (Albany NY) ; 13(1): 241-261, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33173017

RESUMO

MicroRNA 155 (miRNA-155) is frequently dysregulated in hepatocellular carcinoma (HCC) and other cancer types. Toll-like receptor 3 (TLR3), a putative miR-155 target, plays a key role in liver pathophysiology, and its downregulation in HCC cells is associated with apoptosis evasion and poor outcomes. Herein, we examined the ability of in situ self-assembled Au-antimiR-155 nanocomplexes (Au-antimiRNA NCs) to activate TLR3 signaling in HCC cells. Gene expression analysis confirmed an inverse relationship between miR-155 and TLR3 expression in HCC samples, and marked upregulation of miR-155 was observed in HCC cells but not in normal L02 hepatocytes. RNA immunoprecipitation confirmed physical interaction between miR-155 and TLR3, while negative regulation of TLR3 expression by miR-155 was demonstrated by luciferase reporter assays. Au-antimiR-155 NCs were self-assembled within HepG2 HCC cells, but not within control L02 cells. They efficiently silenced miR-155, thereby inhibiting proliferation and migration and inducing apoptosis in HepG2 cells. Molecular analyses suggested these effects are secondary to TLR3 signaling mediating NF-κB transcription, caspase-8 activation, and interleukin-1ß (IL-1ß) release. Our results provide a basis for future studies examining the in vivo applicability of this novel Au-antimiRNA NCs delivery system to halt HCC progression by activating pro-apoptotic TLR3 signaling.


Assuntos
Antagomirs/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/genética , Ouro , Neoplasias Hepáticas/genética , MicroRNAs/antagonistas & inibidores , Nanocompostos , Receptor 3 Toll-Like/efeitos dos fármacos , Apoptose/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Portadores de Fármacos , Células HeLa , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , MicroRNAs/genética , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismo
16.
Nat Prod Res ; 34(14): 2065-2070, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30784312

RESUMO

A new pyrrolidine alkaloid, acanthophoraine A (1), along with six known alkaloids (2-7), had been isolated from the red alga Acanthophora spicifera. The structures of these compounds were identified by spectroscopic analyses. The absolute configuration of 1 was established by ECD calculation. Compound 1 represents the first example of N-isobutyl pyrrolidone with an urea arm. The antimicrobial activity of 1 was also evaluated.[Figure: see text].


Assuntos
Alcaloides/isolamento & purificação , Pirrolidinas/isolamento & purificação , Rodófitas/química , Alcaloides/química , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Conformação Molecular , Estrutura Molecular , Pirrolidinas/química , Análise Espectral
17.
J Cell Biochem ; 120(2): 2547-2553, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30304567

RESUMO

Rheumatoid arthritis fibroblast-like synoviocytes (RAFLS) proliferate abnormally and resist apoptosis. Geldanamycin (GA) and other HSP90 inhibitors have emerged as promising therapeutic agents that inhibited cancer cell growth. In this study, we explored the effects of HSP90 inhibitor, GA, on tumor necrosis factor (TNF)-α-induced proliferation and apoptosis of RAFLS, and the underlying mechanism. Human RAFLS was isolated from the knee joints of patients with RA and subjected to TNF-α treatment in combination of various concentration of GA. We found that GA dose-dependently inhibited TNF-α-induced RAFLS proliferation as measured, but promoted RAFLS apoptosis. Further mechanistic study identified that GA dose-dependently attenuated TNF-α-mediated activation of mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-κB) pathways, both of which are involved in TNF-α-mediated RAFLS proliferation. Moreover, GA-induced apoptosis and mitochondrial damage of RAFLS, as evidenced by increased Bax/Bcl-2 ratio and mitochondrial cytochrome c release, and enhanced cleavages of caspase-3, caspase-9, and poly-(ADP-ribose) polymerase. Collectively, our results revealed that chemical inhibition of HSP90 by GA suppressed TNF-α-induced proliferation of RAFLSs through the MAPK and NF-κB signaling pathways and induces RAFLS apoptosis via mitochondria-dependent pathway. These findings demonstrated for the first time that HSP90 inhibition in RAFLS could be therapeutic beneficial for RA.

18.
Biosens Bioelectron ; 80: 378-384, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26866563

RESUMO

Sensitive and specific analysis of microRNAs (miRNAs) in a single tube without the need of thermal cycler instrument would greatly facilitate the investigation of miRNA-associated regulatory circuits and diseases. Homogeneous isothermal amplification assays are attractive in conducting single tube assays that can minimize contamination-prone steps and simplifies assay procedures. However, the relative low amplification efficiency and high detection background remain as bottlenecks restricting their more versatile applications. In this work, we have developed a novel isothermal exponential enzymatic amplification (IEEA) strategy for miRNAs analysis. By rational triple cascade amplification cycles of target recycling, nicking-replication reaction, and DNAzyme catalysis, the strategy exhibited high signal amplification efficiency (10(4)-10(9) folds of amplification in 1h) with very low detection background and excellent specificity. As a result, the miR-27a target model was rapidly determined with a limit of detection down to 0.79 aM (S/N=3), corresponding to 94 copies of the miRNA molecule in a 200 µL sample solution. The levels of miR-27a in atherosclerotic sprague-dawley rats were accurately quantified. The strategy is anticipated to have an important impact on the development of simple and rapid molecular diagnostic applications for any short oligonucleotides.


Assuntos
Aterosclerose/genética , MicroRNAs/análise , Técnicas de Amplificação de Ácido Nucleico/métodos , Animais , Técnicas Biossensoriais/métodos , Limite de Detecção , Masculino , MicroRNAs/genética , Ratos Sprague-Dawley
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