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1.
Pharmacol Res ; 153: 104657, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31982488

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide and constitutes a major risk factor for progression to cirrhosis, liver failure and hepatocellular carcinoma (HCC). The occurrence of NAFLD is closely associated with abnormal lipid metabolism and implies a high risk of type 2 diabetes and cardiovascular disease. Therefore, specific and effective drugs for the prevention and treatment of NAFLD are necessary. Hypericin (HP) is one of the main active ingredients of Hypericum perforatum L., and we previously revealed its protective role in islet ß-cells and its effects against type 2 diabetes. In this study, we aimed to explore the preventive and therapeutic effects of HP against NAFLD and the underlying mechanisms in vitro and in vivo. Here, we demonstrated that HP improved cell viability by reducing apoptosis and attenuated lipid accumulation in hepatocytes both in vitro and in vivovia attenuating oxidative stress, inhibiting lipogenesis and enhancing lipid oxidization. Thus, HP exhibited significant preventive and therapeutic effects against HFHS-induced NAFLD and dyslipidemia in mice. Furthermore, we demonstrated that HP directly bound to PKACα and activated PKA/AMPK signaling to elicit its effects against NAFLD, suggesting that PKACα is one of the drug targets of HP. In addition, the enhancing effect of HP on lipolysis in adipocytes through the activation of PKACα was also elucidated. Together, the conclusions indicated that HP, of which one of the targets is PKACα, has the potential to be used as a preventive or therapeutic drug against NAFLD or abnormal lipid metabolism in the future.

2.
Biomed Pharmacother ; 121: 109615, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31707343

RESUMO

Psoriasis is considered an immune-mediated inflammatory skin disorder that affects the quality of life of nearly four percent of the world population. Considering the side effects of existing therapeutic drugs and the urgent need for new drug development, we screened more than 250 traditional Chinese medicine compounds to identify drugs that significantly reduced the viability of human HaCaT keratinocytes, a psoriasis-related model cell line. Convallatoxin (CNT) was found to be a highly effective inhibitor of HaCaT cell viability. Subsequent mechanistic studies revealed that CNT induced HaCaT cell death by necroptosis rather than by apoptosis. CNT destroyed the membrane integrity of HaCaT cells, as detected by nuclear propidium iodide (PI) staining and lactate dehydrogenase (LDH) release. Additionally, the intercellular levels of adenosine triphosphate (ATP) were lower in HaCaT cells treated with CNT than in control HaCaT cells, and typical necroptosis-associated characteristics were observed by electron microscopy in cells treated with CNT. Furthermore, compared with control HaCaT cells, CNT-treated HaCaT cells produced more reactive oxygen species (ROS), but this effect was inhibited by the antioxidants N-acetyl-cysteine (NAC), diphenyleneiodonium chloride (DPI), and apocynin and the necroptosis inhibitor Nec-1. In addition, antioxidant treatment attenuated necroptotic cell death, suggesting that CNT-induced HaCaT necroptosis is mediated by oxidative stress. More importantly, CNT ameliorated skin lesions and inflammation in imiquimod (IMQ)- and 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced psoriasis-like mouse models. In conclusion, our results demonstrate that CNT is cytotoxic against HaCaT cells in vitro and exerts antipsoriatic activities in two mouse models of psoriasis in vivo, making CNT a potential promising candidate drug for future research.

3.
Invest Ophthalmol Vis Sci ; 60(13): 4084-4096, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31574534

RESUMO

Purpose: To investigate whole transcriptional differences between proliferative diabetic retinopathy (PDR) neovascular membranes (NVMs) and retinas, and the regulatory genes participating in retinal neovascularization in PDR. Methods: We used high-throughput sequencing technology to capture the whole-genome gene expression levels of all participants, including 23 patients with PDR or branch retinal vein occlusion (BRVO), 3 normal retinal samples, and 2 retinal samples from type II diabetic (T2D) eyes by donation, followed by analyses of expression patterns using bioinformatics methods, then validation of the data by in situ hybridization and Western blotting. Results: We showed that transcriptional profiles of the NVMs were distinct from those of the retinas. Angiogenesis growth factors VEGFC, ANGPT1, ANGPT2, and EFNB2, and their receptors FLT4, TIE1, TIE2, and EPHB4, respectively, were overexpressed. Expression of VEGFA was highly upregulated in T2D retina, but low in the NVMs, while angiogenesis transcription factors, including ETS1 and ERG, were coordinately upregulated in NVMs. Conclusions: This study described a PDR neovascularization model in which pathological retina-secreted vascular endothelial growth factor A (VEGFA) enhanced the expression of a set of angiogenesis transcription factors and growth factors, to cooperatively induce the retinal neovascularization. Based on these results, novel potential therapeutic targets and biomarkers for PDR treatment and diagnosis are suggested.


Assuntos
Angiopoietina-1/metabolismo , Retinopatia Diabética/metabolismo , Efrina-B2/metabolismo , Neovascularização Retiniana/metabolismo , Fator C de Crescimento do Endotélio Vascular/metabolismo , Humanos , Receptor EphB4/metabolismo , Receptor de TIE-1/metabolismo , Receptor TIE-2/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Oclusão da Veia Retiniana/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismo
4.
Eur J Pharmacol ; 863: 172680, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31563649

RESUMO

Psoriasis is a common dermatosis causing considerable inconvenience to 4% of the general population. Traditional psoriasis treatments often cause side effects, drug resistance and complications, necessitating development of safer and more effective treatments. In this study, we screened over 600 natural compounds to identify viability inhibitors of human HaCaT keratinocytes cultured in vitro. The results showed that nitidine chloride was a highly effective inhibitor. Further studies revealed that nitidine chloride inhibited HaCaT proliferation and induced S phase cell cycle arrest; these effects were associated with reduced DNA synthesis, decreased Ki67, cyclin A, and cyclin D1 levels, and increased p53 protein expression. Nitidine chloride also significantly downregulated bcl-2 and upregulated bax, cleaved caspase-9 and cleaved caspase-3. Mechanistic studies revealed that nitidine chloride-induced apoptosis involved the c-Jun N-terminal kinase (JNK) pathway. More importantly, in 12-O-tetradecanoyl-phorbol-13-acetate (TPA)- and imiquimod (IMQ)-induced epidermal hyperplasia and inflammation models, nitidine chloride inhibited topical edema in mouse ear and back skin, substantially reducing tissue thickness and weight. In some cases, nitidine chloride also ameliorated conditions caused by TPA and IMQ, such as angiogenesis and infiltration of large numbers of inflammatory cells around blood vessels. Additionally, nitidine chloride inhibited the expression of various proinflammatory cytokines in the two animal models. In conclusion, our results are the first to demonstrate that nitidine chloride inhibits the proliferation of HaCaT cells, induces apoptosis partly via the JNK signaling pathway in vitro and ameliorates skin lesions and inflammation in vivo, making it an appropriate candidate for psoriasis treatment.

5.
Chem Pharm Bull (Tokyo) ; 67(10): 1076-1081, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31406093

RESUMO

Histone deacetylases (HDACs) are enzymes that play a key role in structural modification and gene expression. The overexpression of HDAC is associated with cancer, and thus inhibiting the enzyme could be an efficient cancer therapy. To discover new HDAC inhibitors (HDACis), we proposed an improved protocol combining a hierarchical pharmacophore search, molecular docking, and molecular dynamic simulations. The test results showed that the improved screening protocol effectively reduced the false-positive rates of drug-like chemicals. Based on the protocol, we obtained 16 hit compounds as potential HDACis from the Life Chemicals database. Enzyme inhibition experiments showed that two of the hit chemical compounds had HDAC-inhibitory effects. In vitro assays showed that Z165155756 could selectively inhibit the proliferation of cancer cells and specifically promoted apoptosis and induced G1/S phase arrest in A2780 cells. It may have potential therapeutic effects in ovarian cancer and is worthy of further investigation.


Assuntos
Antineoplásicos/análise , Antineoplásicos/farmacologia , Descoberta de Drogas , Inibidores de Histona Desacetilases/análise , Inibidores de Histona Desacetilases/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores de Histona Desacetilases/química , Histona Desacetilases/metabolismo , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Relação Estrutura-Atividade
6.
Int J Biol Sci ; 15(7): 1472-1487, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31337977

RESUMO

A decrease in islet ß-cell mass is closely associated with the development and progression of diabetes. Therefore, protection against ß-cell loss is an essential measure to prevent and treat diabetes. In this study, we investigated the protective effects of non-photoactivated hypericin, a natural compound, on ß-cells both in vitro and in vivo. In vitro, hypericin greatly improved INS-1 cell viability under high-glucose and high-fatty-acid conditions by inhibiting glucotoxicity- and lipotoxicity-induced apoptosis and nitric oxide (NO) production. Then, we further demonstrated that hypericin elicited its protective effects against glucotoxicity and lipotoxicity in INS-1 cells by attenuating the reduction in pancreatic duodenal homeobox-1 (PDX1) expression and Erk activity. In vivo, prophylactic or therapeutic use of hypericin inhibited islet ß-cell apoptosis and enhanced the anti-oxidative ability of pancreatic tissue in high-fat/high-sucrose (HFHS)-fed mice, thus alleviating ß-cell loss and maintaining or improving ß-cell mass and islet size. More importantly, hypericin treatment decreased fasting blood glucose, improved glucose intolerance and insulin intolerance, and alleviated hyperinsulinaemia in HFHS-fed mice. Therefore, hypericin showed preventive and therapeutic effects against HFHS-induced onset of type II diabetes in mice. Hypericin possesses great potential for development as an anti-diabetes drug in the future.

7.
FEBS J ; 286(18): 3718-3736, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31349381

RESUMO

Glucotoxicity or lipotoxicity leads to hyperglycemia and insulin secretion deficiency, which are important causes for the onset of type 2 diabetes mellitus (T2DM). Thus, the restoration of ß-cell function is a long-sought goal in diabetes research. Previous studies have implicated pancreatic and duodenal homeobox 1 gene (Pdx1) in ß-cell function and insulin secretion. In this study, we established a Pdx1 promoter-dependent luciferase system and identified the natural compound dracorhodin perchlorate (DP) as an effective promotor of Pdx1 expression. We further demonstrated that DP could significantly inhibit ß-cell apoptosis induced by 33 mm glucose or 200 µm palmitate by interfering with endoplasmic reticulum stress and mitochondrial pathways and enhance insulin secretion as well. These effects were associated with enhanced activities of Erk1/2, which in turn promoted Pdx1 expression and increased the ratio of Bcl2/Bax, since inhibition of the Erk1/2 pathway abolished the DP-induced expression of Pdx1 and suppression of apoptosis. In addition, our in vivo results in diabetic mice indicated that DP treatment lowered blood glucose, raised insulin levels, enhanced Pdx1 expression and increased islet size and number in the pancreas of diabetic mice. Our findings suggest that Pdx1 is a potential target molecule of DP in the treatment of T2DM via the inhibition of glucotoxicity- or lipotoxicity- induced ß-cell apoptosis and the attenuation of insulin secretion dysfunction.

8.
Sci Rep ; 9(1): 2350, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30787420

RESUMO

Histone deacetylases (HDACs) can enzymatically transferred acetyl functional group from protein or lysine residues of histone, so they can regulate the expression of lots of genes. Now HDACs are used as drug targets and many HDAC inhibitors (HDACis) were approved for cancer therapy or in clinical trials. However, the physiological mechanisms and regulatory processes of HDACi anti-cancer effects are largely unexplored and uncompleted. Here we use the virtual screening workflow obtained 25 hit compounds and ZINC24469384 can significantly inhibit HDAC activity while arrest cell cycle at G1/S phase and significantly induced HepG2 cell apoptosis, time-course RNA-seq demonstrate that HepG2 cells transcriptionally respond to ZINC24469384. Pathway analysis of DEGs and DASGs reveal that NR1H4 may play an important role in ZINC24469384-induced anti-proliferation effect and is dramatically alleviated by down-regulating the SOCS2 expression and promoting STAT3 phosphorylation in knockdown NR1H4 HepG2 cells. Analysis based on TCGA database indicated that NR1H4 and SOCS2 were downregulated in liver cancer, this suggest NR1H4 and SOCS2 may play an important role in tumorigenesis. These results indicated that ZINC24469384 is a novel benzamine lead compound of HDACi and provides a novel mechanism for HDACi to inhibit cancer.

9.
Dig Dis Sci ; 64(6): 1548-1559, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30627917

RESUMO

BACKGROUND/AIM: The miR-181 family plays an important role in the regulation of various cellular functions. However, whether miR-181b-5p mediates hepatic insulin resistance remains unknown. In this study, we investigated the effect of miR-181b-5p on the regulation of hepatic glycogen synthesis. METHODS: The miR-181b-5p levels in the livers of diabetic mice were detected by real-time PCR. The glycogen levels and AKT/GSK pathway activation were examined in human hepatic L02 cells and HepG2 cells transfected with miR-181b-5p mimic or inhibitor. The potential target genes of miR-181b-5p were evaluated using a luciferase reporter assay and Western blot analysis. EGR1-specific siRNA and pCMV-EGR1 were used to further determine the role of miR-181b-5p in hepatic glycogen synthesis in vitro. Hepatic inhibition of miR-181b-5p in mice was performed using adeno-associated virus 8 (AAV8) vectors by tail intravenous injection. RESULTS: The miR-181b-5p levels were significantly decreased in the serum and livers of diabetic mice as well as the serum of type 2 diabetes patients. Importantly, inhibition of miR-181b-5p expression impaired the AKT/GSK pathway and reduced glycogenesis in hepatocytes. Moreover, upregulation of miR-181b-5p reversed high-glucose-induced suppression of glycogenesis. Further analysis revealed that early growth response 1 (EGR1) was a downstream target of miR-181b-5p. Silencing of EGR1 expression rescued miR-181b-5p inhibition-reduced AKT/GSK pathway activation and glycogenesis in hepatocytes. Hepatic inhibition of miR-181b-5p led to insulin resistance in C57BL/6 J mice. CONCLUSION: We demonstrated that miR-181b-5p contributes to glycogen synthesis by targeting EGR1, thereby regulating PTEN expression to mediate hepatic insulin resistance.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Glicogênio/biossíntese , Resistência à Insulina , Fígado/metabolismo , MicroRNAs/metabolismo , Adulto , Animais , Diabetes Mellitus Tipo 2/genética , Modelos Animais de Doenças , Proteína 1 de Resposta de Crescimento Precoce/genética , Feminino , Células Hep G2 , Humanos , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Pessoa de Meia-Idade , PTEN Fosfo-Hidrolase/metabolismo , Transdução de Sinais
10.
Eur J Pharmacol ; 836: 75-82, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30096296

RESUMO

Endoplasmic reticulum (ER) stress, together with unfolded protein response (UPR), can remove unfolded proteins and promote survival. However, severe and prolonged ER stress leads to cell death, tissue injury, and many serious diseases. Therefore, it is essential to identify drugs that can attenuate ER stress for ER-related disease treatment. A great deal of research shows that selenoprotein S (SelS) is a sensitive and ideal marker of ER stress. Here, we used a firefly luciferase reporter driven by SelS gene promoter to screen natural compounds that can attenuate ER stress. Then we identified compound 20(S)-25-methoxyl-dammarane-3ß,12ß,20-triol (25-OCH3-PPD) could inhibit the promoter activity of SelS, further results showed that 25-OCH3-PPD effectively inhibited tunicamycin (TM) induced up-regulation of SelS expression in both mRNA and protein levels. Moreover, 25-OCH3-PPD significantly inhibited glucose-regulated protein 78 (GRP78; the major ER stress marker) expression in TM-induced ER stress in HepG2 and HEK293T cells, suggesting that 25-OCH3-PPD could attenuate ER stress in these cells. Mechanism studies showed that 25-OCH3-PPD significantly activated ERK/MAPK signaling pathway, and the inhibition of ERK/MAPK by U0126 dramatically abolished the inhibitory effect of 25-OCH3-PPD on ER stress, suggesting that 25-OCH3-PPD attenuated ER stress at least partially through activation of ERK/MAPK signaling pathway. Taken together, our studies indicate that 25-OCH3-PPD is a novel small molecular compound reducing ER stress, and a potential drug for treating diseases associated with ER stress.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Triterpenos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células HEK293 , Células Hep G2 , Humanos , Proteínas de Membrana/genética , Selenoproteínas/genética , Regulação para Cima/efeitos dos fármacos
11.
Biochem Biophys Res Commun ; 502(2): 283-288, 2018 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-29842883

RESUMO

TSP50, a testis-specific gene encoding a serine protease-like protein, was specifically expressed in the spermatocytes of testes but abnormally activated and expressed in many different kinds of cancers. Here, we aimed to analyze the expression of TSP50 in mouse embryo and its function in early embryonic development. Firstly, the distribution of TSP50 in oocytes and embryonic development was characterized by immunofluorescence, RT-PCR and western blotting, and the results showed that TSP50 was detected at all studied stages with a dynamic expression pattern. When overexpressed TSP50 in zygotes by microinjection, the zygotes development was highly accelerated. On the contrary, knocking down TSP50 expression by RNA interference greatly retarded the zygote development. Furthermore, TSP50 expression at embryonic day 6.5 (E6.5), day 8.5 (E8.5) and day 10.5 (E10.5) were increasingly enhanced, However, the expression of TSP50 decreased gradually in the development and differentiation of cardiac myocyte from E12.5 to postnatal (P0). Additionally, we found that TSP50 expression was decreased during cardiac myocyte differentiation of P19 cells. Overexpression of TSP50 could decrease the expression of GATA-4, and knockdown of TSP50 markedly increase the expression of GATA-4. Taken together, our data indicate that TSP50 may play an important role during the process of mouse embryonic development as well as myocardial cell differentiation.


Assuntos
Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/enzimologia , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Animais , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Transição Epitelial-Mesenquimal/genética , Transição Epitelial-Mesenquimal/fisiologia , Feminino , Coração Fetal/embriologia , Coração Fetal/enzimologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Técnicas de Silenciamento de Genes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Gravidez
12.
Eur J Pharmacol ; 828: 60-66, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29555504

RESUMO

A high level of APOC3 expression is an independent risk factor for some lipid metabolism-related diseases, such as cardiovascular disease (CVD), nonalcoholic fatty liver disease (NAFLD) and atherosclerosis (AS). This suggests that down-regulating APOC3 expression is a potential way of regulating lipid levels. In this study, we used luciferase reporter screening to identify a natural compound, alantolactone (ALA), that can inhibit the promoter activity of APOC3. ALA decreased APOC3 expression at both mRNA and protein levels. Then we pretreated L02 liver cells with oxLDL to investigate the function of ALA in lipid homeostasis. Intriguingly, ALA attenuated oxLDL-induced foam cell formation by reducing total cholesterol (TC) and triglyceride (TG) contents. Furthermore, these results could be reversed by overexpressing APOC3 protein. ALA inhibited tyrosine phosphorylation (Tyr705pho) of STAT3 to down-regulate APOC3 expression. Intriguingly, overexpression of a wild-type STAT3 or a constitutively active form of STAT3 (STAT3-C) up-regulated APOC3 expression and partly reversed the effect of ALA in oxLDL-induced L02 cells. Overexpression of wild-type STAT3 also increased TC but not TG contents in L02 cells. However, overexpression of STAT3-C significantly increased TC and TG contents, and the effect of ALA was partly attenuated by STAT3-C, although this was not statistically significant. These results suggest that ALA attenuates lipid accumulation through down-regulation of APOC3 expression, at least in part by inhibiting STAT3 signaling.


Assuntos
Apolipoproteína C-III/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Homeostase/efeitos dos fármacos , Lactonas/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Sesquiterpenos de Eudesmano/farmacologia , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos , Humanos , Lipoproteínas LDL/farmacologia , Fator de Transcrição STAT3/metabolismo
13.
Sci Rep ; 8(1): 1479, 2018 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-29367618

RESUMO

Prohibitin 2 (PHB2), as a conserved multifunctional protein, is traditionally localized in the mitochondrial inner membrane and essential for maintenance of mitochondrial function. Here, we investigated the role of PHB2 in human rhabdomyosarcoma (RMS) RD cells and found substantial localization of PHB2 in the nucleolus. We demonstrated that PHB2 knockdown inhibited RD cell proliferation through inducing cell cycle arrest and suppressing DNA synthesis. Meanwhile, down-regulation of PHB2 also induced apoptosis and promoted differentiation in fractions of RD cells. In addition, PHB2 silencing led to altered nucleolar morphology, as observed by transmission electron microscopy, and impaired nucleolar function, as evidenced by down-regulation of 45S and 18S ribosomal RNA synthesis. Consistently, upon PHB2 knockdown, occupancy of c-Myc at the ribosomal DNA (rDNA) promoter was attenuated, while more myoblast determination protein 1 (MyoD) molecules bound to the rDNA promoter. In conclusion, our findings suggest that nucleolar PHB2 is involved in maintaining nucleolar morphology and function in RD cells by regulating a variety of transcription factors, which is likely to be one of the underlying mechanisms by which PHB2 promotes tumor proliferation and represses differentiation. Our study provides new insight into the pathogenesis of RMS and novel characterizations of the highly conserved PHB2 protein.


Assuntos
Nucléolo Celular/metabolismo , Proliferação de Células , RNA Ribossômico/genética , Proteínas Repressoras/metabolismo , Rabdomiossarcoma/patologia , Transcrição Genética , Apoptose , Diferenciação Celular , Humanos , Proteína MyoD/metabolismo , RNA Interferente Pequeno/genética , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Rabdomiossarcoma/genética , Rabdomiossarcoma/metabolismo , Células Tumorais Cultivadas
14.
Apoptosis ; 22(11): 1404-1418, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28864870

RESUMO

The pro-inflammatory cytokine interleukin 6 (IL-6), via activating its downstream JAK/STAT3 and Ras/ERK signaling pathways, is involved in cell growth, proliferation and anti-apoptotic activities in various malignancies. To screen inhibitors of IL-6 signaling, we constructed a STAT3 and ERK dual-pathway responsive luciferase reporter vector (Co.RE). Among several candidates, the natural compound 20(S)-25-methoxyl-dammarane-3ß, 12ß, 20-triol (25-OCH3-PPD, GS25) was identified to clearly inhibit the luciferase activity of Co.RE. GS25 was confirmed to indeed inhibit activation of both STAT3 and ERK pathways and expression of downstream target genes of IL-6, and to predominantly decrease the viability of HepG2 cells via induction of cell cycle arrest and apoptosis. Interestingly, GS25 showed preferential inhibition of HepG2 cell viability relative to normal liver L02 cells. Further investigation showed that GS25 could not induce apoptosis and block activation of STAT3 and ERK pathways in L02 cells as efficiently as in HepG2 cells, which may result in differential effects of GS25 on malignant and normal liver cells. In addition, GS25 was found to potently suppress the expression of endogenous STAT3 at a higher concentration and dramatically induce p38 phosphorylation in HepG2 cells, which could mediate its anti-cancer effects. Finally, we demonstrated that GS25 also inhibited tumor growth in HepG2 xenograft mice. Taken together, these findings indicate that GS25 elicits its anti-cancer effects on HepG2 cells through multiple mechanisms and has the potential to be used as an inhibitor of IL-6 signaling. Thus, GS25 may be developed as a treatment for hepatocarcinoma with low toxicity on normal liver tissues as well as other inflammation-associated diseases.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Regulação Neoplásica da Expressão Gênica , Ginsenosídeos/farmacologia , Hepatoblastoma/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Fator de Transcrição STAT3/genética , Animais , Antineoplásicos Fitogênicos/síntese química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Proliferação de Células/efeitos dos fármacos , Feminino , Genes Reporter , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Ginsenosídeos/química , Células Hep G2 , Hepatoblastoma/genética , Hepatoblastoma/metabolismo , Hepatoblastoma/patologia , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Luciferases/genética , Luciferases/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Nus , Fator de Transcrição STAT3/agonistas , Fator de Transcrição STAT3/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
15.
Front Microbiol ; 8: 1738, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28955316

RESUMO

Streptococcus mutans has been reported as a primary cariogenic pathogen associated with dental caries. The bacteria can produce glucosyltransferases (Gtfs) to synthesize extracellular polysaccharides (EPSs) that are known as virulence factors for adherence and formation of biofilms. Therefore, an ideal inhibitor for dental caries is one that can inhibit planktonic bacteria growth and prevent biofilm formation. Bergenia crassifolia (L.), widely used as a folk medicine and tea beverage, has been reported to have a variety of bioactivities. The present study aimed to explore the effect of B. crassifolia (L.) leaf extracts on the biofilm of Streptococcus mutans. The B. crassifolia (L.) leaf extracts showed inhibitory effects by decreasing viability of bacteria within the biofilm, as evidenced by the XTT assay, live/dead staining assay and LDH activity assay, and could decrease the adherence property of S. mutans through inhibiting Gtfs to synthesize EPSs. In addition, the reduced quantity of EPSs and the inhibition of Gtfs were positively correlated with concentrations of test samples. Finally, the MTT assay showed that the extracts had no cytotoxicity against normal oral cells. In conclusion, the extracts and sub-extracts of B. crassifolia leaves were found to be antimicrobial and could reduce EPS synthesis by inhibiting activities of Gtfs to prevent bacterial adhesion and biofilm formation. Therefore, B. crassifolia leaves have potential to be developed as a drug to prevent and cure dental caries.

16.
Biomacromolecules ; 18(8): 2306-2314, 2017 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-28654745

RESUMO

The capacity to specifically destroy cancer cells while avoiding normal tissue is urgently desirable in cancer treatment. Herein, a photothermal-trigger-released system serves as a photoacoustic imaging agent constructed by entrapping diketopyrrolopyrrole-based conjugated polymers and curcumin in a poly(ethylene glycol) (PEG)-protected thermoresponsive liposomal phospholipid bilayer. This lipid nanostructure can improve the bioavailability of hydrophobic agents for photothermal treatment with high efficiency and deliver the anticancer drug curcumin to the tumor site actuated by near-infrared (NIR) irradiation. A significantly enhanced combined therapeutic effect to HepG2 tumor-bearing mice was acquired in contrast to the result of single therapy alone. These liposomes with the capability of photoacoustic imaging, greater EPR-induced accumulation in tumor sites, and hyperthermia ablation for photothermal chemotherapy show potential for photoacoustic imaging-guided photothermal/chemo combined therapeutic applications.


Assuntos
Hipotermia Induzida , Cetonas , Neoplasias Experimentais , Técnicas Fotoacústicas , Fototerapia , Polietilenoglicóis , Pirróis , Animais , Células Hep G2 , Humanos , Cetonas/química , Cetonas/farmacologia , Lipossomos , Camundongos , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/terapia , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Pirróis/química , Pirróis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Int J Mol Sci ; 18(4)2017 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-28394269

RESUMO

Ginkgolide A (GA) is a natural compound isolated from Ginkgo biloba and has been used to treat cardiovascular diseases and diabetic vascular complications. However, only a few studies have been conducted on the anti-inflammatory effects of GA. In particular, no related reports have been published in a common inflammation model of lipopolysaccharide (LPS)-stimulated macrophages, and the anti-inflammatory mechanisms of GA have not been fully elucidated. In the present study, we extensively investigated the anti-inflammatory potential of GA in vitro and in vivo. We showed that GA could suppress the expression of pro-inflammatory mediators (cyclooxygenase-2 (COX-2) and nitric oxide (NO) and pro-inflammatory cytokines (tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1ß) in LPS-treated mouse peritoneal macrophages, mouse macrophage RAW264.7 cells, and differentiated human monocytes (dTHP-1) in vitro. These effects were partially carried out via downregulating Nuclear factor kappa-B (NF-κB), Mitogen-activated protein kinases (MAPKs) (p38 mitogen-activated protein kinase and extracellular signal-regulated kinase (ERK), but not c-Jun N-terminal kinase (JNK), and activating the AMP-activated protein kinase (AMPK) signaling pathway also seems to be important. Consistently, GA was also shown to inhibit the LPS-stimulated release of TNF-α and IL-6 in mice. Taken together, these findings suggest that GA can serve as an effective inflammatory inhibitor in vitro and in vivo.


Assuntos
Ginkgolídeos/farmacologia , Inflamação/prevenção & controle , Lactonas/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Animais , Western Blotting , Linhagem Celular , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/metabolismo , Citocinas/sangue , Citocinas/genética , Citocinas/metabolismo , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/sangue , Inflamação/induzido quimicamente , Mediadores da Inflamação/sangue , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Macrófagos/metabolismo , Macrófagos Peritoneais/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos
18.
Mol Immunol ; 82: 94-103, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28064070

RESUMO

Maspin (mammary serine protease inhibitor) is a non-inhibitory member of the serine protease inhibitor superfamily and a tumor suppressor in several cancers due to its ability to inhibit cell invasion, angiogenesis, and promote apoptosis. However, its immunomodulatory function remains largely unexplored. Thus, we explored the potential link between Maspin and macrophage function, first evaluating the regulatory effects of conditioned medium (CM) of a Maspin-overexpressing CHO cell strain on mouse peritoneal macrophage phagocytosis and cytokine secretion. Next, we used a transwell co-culture system and recombinant Maspin (rMaspin) to confirm the effects of Maspin on macrophages, and attempted to clarify the underlying mechanisms. We found that irrespective of CM, rMaspin or co-culture of Maspin-overexpressing cells with macrophages impaired macrophages phagocytosing Saccharomyces cerevisiae. Furthermore, q-RT-PCR or ELISA confirmed increased IL-1ß, TNF-α, IFN-γ, IL-6, IL-12, IL-10, and M1 marker iNOS production in macrophages after Maspin stimulation, but TGF-ß and M2 marker Arg-1 production were suppressed. Western blot showed activated NF-κB signaling in Maspin-stimulated macrophages; upregulated cytokines were lowered, and impaired phagocytosis recovered after blocking NF-κB signaling with PDTC. Thus, Maspin mildly inhibited phagocytic activity, but markedly enhanced inflammatory cytokine production and likely skewed macrophages towards M1 polarization, partially due to activation of NF-κB signaling. These results reveal a novel biological function of Maspin in modulating macrophage activity and may open a new avenue for Maspin-based tumor therapy.


Assuntos
Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Fagocitose , Serpinas/imunologia , Transdução de Sinais/imunologia , Animais , Células CHO , Técnicas de Cocultura , Cricetulus , Citocinas/biossíntese , Ensaio de Imunoadsorção Enzimática , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/imunologia , NF-kappa B/metabolismo , Fagocitose/imunologia , Reação em Cadeia da Polimerase , Serpinas/metabolismo , Transfecção
19.
BMC Pharmacol Toxicol ; 17(1): 32, 2016 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-27443303

RESUMO

BACKGROUND: Histone deacetylases (HDACs) are promising therapeutic targets for the treatment of cancer, diabetes and other human diseases. HDAC inhibitors, as a new class of potential therapeutic agents, have attracted a great deal of interest for both research and clinical applications. Increasing efforts have been focused on the discovery of HDAC inhibitors and some HDAC inhibitors have been approved for use in cancer therapy. However, most HDAC inhibitors, including the clinically approved agents, do not selectively inhibit the deacetylase activity of class I and II HDAC isforms, and many suffer from metabolic instability. This study aims to identify new HDAC inhibitors by using a high-throughput virtual screening approach. METHODS: An integration of in silico virtual screening and in vitro experimental validation was used to identify novel HDAC inhibitors from a chemical database. RESULTS: A virtual screening workflow for HDAC inhibitors were created by integrating ligand- and receptor- based virtual screening methods. Using the virtual screening workflow, 22 hit compounds were selected and further tested via in vitro assays. Enzyme inhibition assays showed that three of the 22 compounds had HDAC inhibitory properties. Among these three compounds, ZINC12555961 significantly inhibited HDAC activity. Further in vitro experiments indicated that ZINC12555961 can selectively inhibit proliferation and promote apoptosis of cancer cells. CONCLUSIONS: In summary, our study presents three new and potent HDAC inhibitors and one of these HDAC inhibitors shows anti-proliferative and apoptosis-inducing activity against various cancer cell lines. These results suggest that the developed virtual screening workflow can provide a useful source of information for the screening and validation of new HDAC inhibitors. The new-found HDAC inhibitors are worthy to further and more comprehensive investigations.


Assuntos
Desenho de Drogas , Inibidores de Histona Desacetilases/química , Inibidores de Histona Desacetilases/farmacologia , Interface Usuário-Computador , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Avaliação Pré-Clínica de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/normas , Células Hep G2 , Humanos , Reprodutibilidade dos Testes
20.
Tumour Biol ; 37(9): 11805-11813, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27039397

RESUMO

While the incidence of cancer continues to increase, the current therapeutic options remain imperfect. Therefore, there is an urgent need to discover new targeted anti-cancer therapies. Testes-specific protease 50 (TSP50) is abnormally expressed in most cancer tissues and downregulation of TSP50 expression can reduce cell proliferation and induce cell apoptosis, which makes it a potential target for cancer therapy. In this study, we constructed a firefly luciferase reporter pGL3-TSP50-3'-UTR as a drug screening model to screen potential candidate compounds that target TSP50 mRNA. We identified the compound 7P3A, which consists of 70 % 25-methoxyl-dammarane-3ß, 12ß, 20-triol and 30 % artemisinin, as being capable of inhibiting the TSP50-3'-UTR reporter activity, as well as the expression of TSP50. Further investigation revealed that 7P3A could inhibit MDA-MB-231 cell proliferation and induce cell cycle arrest, and over-expression of TSP50 partially reversed the effect of 7P3A. In vivo investigation showed that 7P3A could inhibit tumor growth in a xenograft model of breast cancer. These results suggest that 7P3A exhibits anti-cancer effects, in part, through downregulation of TSP50 expression.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Serina Endopeptidases/metabolismo , Regiões 3' não Traduzidas/genética , Animais , Antimaláricos/administração & dosagem , Artemisininas/administração & dosagem , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação para Baixo/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Camundongos Endogâmicos BALB C , Camundongos Nus , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sapogeninas/administração & dosagem , Serina Endopeptidases/genética , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genética , Ensaios Antitumorais Modelo de Xenoenxerto
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