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1.
Chem Biol Interact ; 316: 108917, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31838050

RESUMO

Stearoyl-CoA desaturase (SCD) generates monounsaturated fatty acids (MUFAs) which contribute to cell growth, survival, differentiation, metabolic regulation and signal transduction. Overexpression of SCD is evident and implicated in metabolic diseases such as diabetes and non-alcoholic fatty liver disease. SCD also stimulates canonical Wnt pathway and YAP activation in support of stemness and tumorigenesis. SCD facilitates metabolic reprogramming in cancer which is mediated, at least in part, by regulation of AKT, AMPK, and NF-kB via MUFAs. Our research has revealed the novel positive loop to amplify Wnt signaling through stabilization of LRP5/6 in both hepatic stellate cells and liver tumor-initiating stem cell-like cells. As such, this loop is pivotal in promoting liver fibrosis and liver tumor development. This review summarizes the mechanisms of SCD-mediated tumor promotion described by recent studies and discusses the future prospect for SCD-mediated signaling crosstalk as a potential therapeutic target for cancer.


Assuntos
Carcinogênese , Estearoil-CoA Dessaturase/metabolismo , Animais , Proteínas de Ciclo Celular/metabolismo , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/metabolismo , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Estearoil-CoA Dessaturase/genética , Via de Sinalização Wnt
2.
Biol Res ; 52(1): 60, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31847887

RESUMO

BACKGROUND: Recent studies have confirmed that RASAL1 has an antitumor effect in many cancers, but its functional role and the molecular mechanism underlying in colon cancer has not been investigated. RESULTS: We collected human colon cancer tissues and adjacent non-tumor tissues, human colon cancer cell lines LoVo, CaCo2, SW1116, SW480 and HCT-116, and normal colonic mucosa cell line NCM460. RT-qPCR was used to detect the RASAL1 level in the clinical tissues and cell lines. In LoVo and HCT-116, RASAL1 was artificially overexpressed. Cell viability and proliferation were measured using CCK-8 assays, and cell cycle was detected via PI staining and flow cytometry analysis. RASAL1 significantly inhibited the cell proliferation via inducing cell cycle arrest, suppressed cell cycle associated protein expression, and decreased the lipid content and inhibited the SCD1 expression. Moreover, SCD1 overexpression induced and downregulation repressed cell proliferation by causing cell cycle arrest. Additionally, luciferase reporter assays were performed to confirm the direct binding between SREBP1c, LXRα and SCD1 promoter, we also demonstrated that RASAL1 inhibit SCD1 3'-UTR activity. RASAL1 inhibited tumor growth in xenograft nude mice models and shows inhibitory effect of SCD1 expression in vivo. CONCLUSION: Taken together, we concluded that RASAL1 inhibited colon cancer cell proliferation via modulating SCD1 activity through LXRα/SREBP1c pathway.


Assuntos
Proliferação de Células/fisiologia , Neoplasias do Colo/patologia , Proteínas Ativadoras de GTPase/metabolismo , Receptores X do Fígado/metabolismo , Estearoil-CoA Dessaturase/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Animais , Linhagem Celular Tumoral , Regulação para Baixo , Proteínas Ativadoras de GTPase/genética , Humanos , Receptores X do Fígado/genética , Camundongos , Estearoil-CoA Dessaturase/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/genética
3.
PLoS Genet ; 15(11): e1008375, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31738765

RESUMO

DNA variants that alter gene expression contribute to variation in many phenotypic traits. In particular, trans-acting variants, which are often located on different chromosomes from the genes they affect, are an important source of heritable gene expression variation. However, our knowledge about the identity and mechanism of causal trans-acting variants remains limited. Here, we developed a fine-mapping strategy called CRISPR-Swap and dissected three expression quantitative trait locus (eQTL) hotspots known to alter the expression of numerous genes in trans in the yeast Saccharomyces cerevisiae. Causal variants were identified by engineering recombinant alleles and quantifying the effects of these alleles on the expression of a green fluorescent protein-tagged gene affected by the given locus in trans. We validated the effect of each variant on the expression of multiple genes by RNA-sequencing. The three variants differed in their molecular mechanism, the type of genes they reside in, and their distribution in natural populations. While a missense leucine-to-serine variant at position 63 in the transcription factor Oaf1 (L63S) was almost exclusively present in the reference laboratory strain, the two other variants were frequent among S. cerevisiae isolates. A causal missense variant in the glucose receptor Rgt2 (V539I) occurred at a poorly conserved amino acid residue and its effect was strongly dependent on the concentration of glucose in the culture medium. A noncoding variant in the conserved fatty acid regulated (FAR) element of the OLE1 promoter influenced the expression of the fatty acid desaturase Ole1 in cis and, by modulating the level of this essential enzyme, other genes in trans. The OAF1 and OLE1 variants showed a non-additive genetic interaction, and affected cellular lipid metabolism. These results demonstrate that the molecular basis of trans-regulatory variation is diverse, highlighting the challenges in predicting which natural genetic variants affect gene expression.


Assuntos
Proteínas de Ligação a DNA/genética , Evolução Molecular , Sequências Reguladoras de Ácido Nucleico/genética , Proteínas de Saccharomyces cerevisiae/genética , Estearoil-CoA Dessaturase/genética , Fatores de Transcrição/genética , Sistemas CRISPR-Cas/genética , Ácidos Graxos/genética , Ácidos Graxos/metabolismo , Regulação Fúngica da Expressão Gênica/genética , Proteínas de Fluorescência Verde/genética , Metabolismo dos Lipídeos/genética , Proteínas de Transporte de Monossacarídeos/genética , Mutação de Sentido Incorreto/genética , Fenótipo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
4.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(4): 546-550, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31642233

RESUMO

OBJECTIVE: To investigate the expression of stearoyl-CoA desaturase-1 (SCD1) in breast cancer cell lines. To analyze the effect of inhibiting SCD1 activity on the proliferation and cell cycle of MCF-7 breast cancer cell and its mechanism. METHODS: The expression of SCD1 protein were detected by Western blot techniques in breast cancer cell lines and humanskin fibroblasts.Cell viability of MCF-7 cells treated with MF-438 was measured using MTS assay and IC50 value was calculated.The distribution of cell cycle was determined by PI staining using flow cytometry.The expression of Cyclin D1 was detected by Western blot. The expression of Akt, pAkt, pAMPK and pACC were also detected by Western blot. RESULTS: The expression level of SCD1 in MCF-7 and MDA-MB-231 cells was significantly higher than that in HSF cells (P < 0.05).MF-438 showed a significant dose-dependent proliferation inhibition effect on MCF-7 cells cultured in low serum at a concentration ranging from 100 nmol/L to 100 µmol/L with an IC50 value of (3.9±0.45) µmol/L. After intervention of 5 µmol/L MF-438 in MCF-7 cells, the proportion of cells in S phase and G2/M phase was significantly decreased (P < 0.01), the proportion of cells in G0/G1 phase increased (P < 0.01), and the expression of Cyclin D1 was significantly decreased (P < 0.05); Meanwhile, the expression of pAkt and pAkt/Akt value were significantly decreased (P < 0.05) and the expression of pAMPK and pACC levels were significantly increased (P < 0.05). CONCLUSIONS: SCD1 plays an important role in the occurrence and development of breast cancer. Inhibition of SCD1 activity can inhibit cell cycle progression and impair cell proliferation by down-regulating the Akt pathway and activating the AMPK pathway. Further research on SCD1 is expected to provide a new target for molecular targeted therapy of breast cancer.


Assuntos
Neoplasias da Mama/patologia , Ciclo Celular , Proliferação de Células , Estearoil-CoA Dessaturase/genética , Divisão Celular , Ciclina D1/metabolismo , Humanos , Células MCF-7 , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Estearoil-CoA Dessaturase/antagonistas & inibidores
5.
J Agric Food Chem ; 67(37): 10352-10360, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31503479

RESUMO

The potential for apple peels to mitigate the deleterious effects of a high-fat diet in mice was investigated here. Mice were fed a high-fat diet supplemented with apple powders from three apple varieties or a commercial apple polyphenol. Polyphenols were characterized using colorimetric assays and high-performance liquid chromatography. Mice were tested for standard metabolic parameters. There was a dose response to dietary apple peels, with the higher intake leading to reduced weight gain and adipose tissue mass relative to the lower intake, but none of the treatments were statistically different from the control. The gene expression of liver enzyme stearoyl-CoA desaturase (Scd-1) was correlated with adipose weight, and liver enzyme cytochrome P51 (Cyp51) was downregulated by the apple diets. The feces from a subset of mice were analyzed for polyphenols and for bacteria taxa by next-generation sequencing. The results revealed that the makeup of the fecal microbiota was related to the metabolism of dietary polyphenols.


Assuntos
Biflavonoides/análise , Catequina/análise , Fezes/química , Frutas/metabolismo , Microbioma Gastrointestinal , Malus/metabolismo , Obesidade/dietoterapia , Proantocianidinas/análise , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biflavonoides/metabolismo , Catequina/metabolismo , Dieta Hiperlipídica/efeitos adversos , Frutas/química , Humanos , Masculino , Malus/química , Camundongos , Obesidade/genética , Obesidade/metabolismo , Obesidade/microbiologia , Polifenóis/análise , Polifenóis/metabolismo , Proantocianidinas/metabolismo , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Esterol 14-Desmetilase/genética , Esterol 14-Desmetilase/metabolismo
6.
J Dairy Sci ; 102(12): 11124-11141, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563305

RESUMO

In genome-wide association studies (GWAS), sample size is the most important factor affecting statistical power that is under control of the investigator, posing a major challenge in understanding the genetics underlying difficult-to-measure traits. Combining data sets available from different populations for joint or meta-analysis is a promising alternative to increasing sample sizes available for GWAS. Simulation studies indicate statistical advantages from combining raw data or GWAS summaries in enhancing quantitative trait loci (QTL) detection power. However, the complexity of genetics underlying most quantitative traits, which itself is not fully understood, is difficult to fully capture in simulated data sets. In this study, population-specific and combined-population GWAS as well as a meta-analysis of the population-specific GWAS summaries were carried out with the objective of assessing the advantages and challenges of different data-combining strategies in enhancing detection power of GWAS using milk fatty acid (FA) traits as examples. Gas chromatography (GC) quantified milk FA samples and high-density (HD) genotypes were available from 1,566 Dutch, 614 Danish, and 700 Chinese Holstein Friesian cows. Using the joint GWAS, 28 additional genomic regions were detected, with significant associations to at least 1 FA, compared with the population-specific analyses. Some of these additional regions were also detected using the implemented meta-analysis. Furthermore, using the frequently reported variants of the diacylglycerol acyltransferase 1 (DGAT1) and stearoyl-CoA desaturase (SCD1) genes, we show that significant associations were established with more FA traits in the joint GWAS than the remaining scenarios. However, there were few regions detected in the population-specific analyses that were not detected using the joint GWAS or the meta-analyses. Our results show that combining multi-population data set can be a powerful tool to enhance detection power in GWAS for seldom-recorded traits. Detection of a higher number of regions using the meta-analysis, compared with any of the population-specific analyses also emphasizes the utility of these methods in the absence of raw multi-population data sets to undertake joint GWAS.


Assuntos
Conjuntos de Dados como Assunto , Estudo de Associação Genômica Ampla/veterinária , Glicolipídeos/análise , Glicoproteínas/análise , Metanálise como Assunto , Leite/química , Animais , Bovinos , Cromatografia Gasosa , Diacilglicerol O-Aciltransferase/genética , Ácidos Graxos/análise , Feminino , Estudo de Associação Genômica Ampla/métodos , Genótipo , Locos de Características Quantitativas , Estearoil-CoA Dessaturase/genética
7.
Lipids Health Dis ; 18(1): 168, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477154

RESUMO

BACKGROUND: The alteration of lipid metabolism in cancer cells is recognized as one of the most important metabolic hallmarks of cancer. Membrane rafts defined as plasma membrane microdomains enriched in cholesterol and sphingolipids serve as platforms for signaling regulation in cancer. The main purpose of this study was to evaluate the effect of the cholesterol metabolite, 4-cholesten-3-one, on lipid metabolism and membrane raft integrity in two breast cancer cell lines, MCF-7 and MDA-MB-231. Its ability to reduce cell viability and migration has also been investigated. METHODS: RT-qPCR was performed to evaluate the expression of enzymes involved in lipogenesis and cholesterol synthesis, and ABCG1 and ABCA1 transporters involved in cholesterol efflux. Its effect on cell viability and migration was studied using the MTT assay, the wound healing assay and the Transwell migration assay, respectively. The effect of 4-cholesten-3-one on membrane rafts integrity was investigated by studying the protein expression of flotillin-2, a membrane raft marker, and raft-enriched EGFR by western blot. RESULTS: Interestingly, we found that 4-cholesten-3-one treatment decreased mRNA expression of different enzymes including ACC1, FASN, SCD1 and HMGCR. We further demonstrated that 4-cholesten-3-one increased the expression of ABCG1 and ABCA1. We also found that 4-cholesten-3-one decreased the viability of MCF-7 and MDA-MB-231 cells. This effect was neutralized after treatment with LXR inverse agonist or after LXRß knockdown by siRNA. As a result, we also demonstrated that 4-cholesten-3-one disrupts membrane rafts and cell migration capacity. CONCLUSION: Our results show that 4-cholesten-3-one exerts promising antitumor activity by altering LXR-dependent lipid metabolism in breast cancer cells without increasing lipogenesis.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Colestenonas/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Lipogênese/efeitos dos fármacos , Receptores X do Fígado/genética , Microdomínios da Membrana/efeitos dos fármacos , Transportador 1 de Cassete de Ligação de ATP/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Receptores ErbB/genética , Receptores ErbB/metabolismo , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintase Tipo I/metabolismo , Humanos , Hidroximetilglutaril-CoA Redutases/genética , Hidroximetilglutaril-CoA Redutases/metabolismo , Lipogênese/genética , Receptores X do Fígado/metabolismo , Células MCF-7 , Microdomínios da Membrana/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Transdução de Sinais , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Células THP-1
8.
BMC Cancer ; 19(1): 760, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31370822

RESUMO

BACKGROUNDS: The role of sphere-forming culture in enriching subpopulations with stem-cell properties in hepatocellular carcinoma (HCC) is unclear. The present study investigates its value in enriching cancer stem cells (CSCs) subpopulations and the mechanism by which HCC CSCs are maintained. METHODS: HCC cell lines and fresh primary tumor cells were cultured in serum-free and ultra-low attachment conditions to allow formation of HCC spheres. In vitro and in vivo experiments were performed to evaluate CSC characteristics. Expression levels of CSC-related genes were assessed by qRT-PCR and the correlation between sphere formation and clinical characteristics was investigated. Finally, gene expression profiling was performed to explore the molecular mechanism underlying HCC CSC maintenance. RESULTS: We found that both cell lines and primary tumor cells formed spheres. HCC spheres possessed the capacity for self-renewal, proliferation, drug resistance, and contained different subpopulations of CSCs. Of interest, 500 sphere-forming Huh7 cells or 200 primary tumor cells could generate tumors in immunodeficient animals. Sphere formation correlated with size, multiple tumors, satellite lesions, and advanced stage. Further investigation identified that the PPARα-SCD1 axis plays an important role in maintenance of the CSC properties of HCC sphere cells by promoting nuclear accumulation of ß-Catenin. Inhibition of SCD1 interfered with sphere formation, down-regulated expression of CSC-related markers, and reduced ß-Catenin nuclear accumulation. CONCLUSIONS: Sphere-forming culture can effectively enrich subpopulations with stem-cell properties, which are maintained through activation of the PPARα-SCD1 axis. Therefore, we suggest that targeting the SCD1-related CSC machinery might provide a novel insight into HCC treatment.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Células-Tronco Neoplásicas/patologia , Esferoides Celulares/patologia , Estearoil-CoA Dessaturase/metabolismo , Animais , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células , Autorrenovação Celular , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/patologia , Camundongos , Camundongos SCID , Terapia de Alvo Molecular , PPAR alfa/metabolismo , Transdução de Sinais , Estearoil-CoA Dessaturase/genética , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Phytomedicine ; 63: 152999, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31280138

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome. Recently, the inhibitory effects of flavone glycosides isolated from Sicyos angulatus extract on hepatic lipid accumulation in vitro were demonstrated. However, the effects of S. angulatus extract and its major flavonoid glycoside on in vivo hepatic steatosis induced by a high-fat diet have not yet been established. HYPOTHESIS/PURPOSE: The aim of this study was to investigate the effects of S. angulatus extract and its major flavonoid glycoside, kaempferol 3-O-[α-l-rhamnopyranosyl-(1→6)]-ß-d-glucopyranosyl-7-O-α-l-rhamnopyranoside, on hepatic steatosis in high-fat diet-fed mice, which serves as a model of NAFLD. In addition, attempts have been made to chemically profile the metabolites involved in the activity of the S. angulatus extract. METHODS: C57BL/6 J mice were divided into vehicle, total extract of S. angulatus (SA; 50, 100 and 200 mg/kg) and major active component (20 mg/kg) groups. The mice were fed a high-fat diet (HFD) with or without S. angulatus extract or its major single compound for 10 weeks. Chemical identification was carried out using ultra-high-pressure liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UHPLC-qTOF-MS/MS) and then quantified by HPLC-DAD. RESULTS: Administration of S. angulatus extract significantly lowered plasma ALT and AST levels in HFD-fed mice compared to those of the vehicle group. The hepatic lipid content, as evidenced by oil-red O staining and quantification, was significantly lower in the S. angulatus-administered group, and the effect was dose dependent. These beneficial effects of S. angulatus extract were related to the decreased expression of hepatic genes involved in fatty acid (ACC1, FAS and SCD1) and triglyceride (DGAT) synthesis. The expression levels of two key transcription factors regulating lipogenesis, SREBP-1c and PPARγ, were significantly suppressed in the liver by administration of S. angulatus extract with HFD. Treatment of the HFD-fed mice with the major compound isolated from S. angulatus extract resulted in improved liver function along with an anti-steatotic effect similar to the results seen with S. angulatus extract. For the standardization of the S. angulatus extract, 23 compounds were identified based on MS/MS fragmentation and UV spectroscopy. Quantitative analysis of the major compound showed that the major component was present in 15.35 ± 0.01 mg/g of total extract. CONCLUSION: These findings suggest that S. angulatus extract and its major component have the potential to improve liver function and hepatic steatosis in diet-induced obese mice.


Assuntos
Cucurbitaceae/química , Glicosídeos/farmacologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Extratos Vegetais/farmacologia , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica , Glicosídeos/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Extratos Vegetais/química , Espectrofotometria Ultravioleta , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Espectrometria de Massas em Tandem
10.
Food Funct ; 10(8): 4966-4974, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31343008

RESUMO

trans-Trismethoxy resveratrol (TMR) is a methyl analog of resveratrol. It is found to exhibit enhanced biological effects compared to resveratrol, such as inhibition of cancer cell growth and pro-apoptotic activities. However, the role of TMR in lipid metabolism is not fully understood. In this study, we used Caenorhabditis elegans, an in vivo nematode model which has been widely applied in disease research, including research on obesity, to investigate the effect of TMR on lipid metabolism. Treatment with TMR (100 and 200 µM) for 4 days significantly reduced triglyceride accumulation (14% and 20% reduction over the control, respectively) of C. elegans, without affecting nematode growth, food intake and reproduction. Treatment with TMR significantly downregulated stearoyl-CoA desaturase genes, fat-6 and fat-7, accompanied by a decrease in the desaturation index of fatty acids, the ratio of oleic acid to stearic acid. These results suggest that TMR inhibits fat accumulation by downregulating stearoyl-CoA desaturase in C. elegans.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/metabolismo , Gorduras/metabolismo , Ácidos Graxos Dessaturases/metabolismo , Resveratrol/farmacologia , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Ácidos Graxos Dessaturases/genética , Resveratrol/química , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Triglicerídeos/metabolismo
11.
Int J Mol Sci ; 20(12)2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31207892

RESUMO

AIM: Primary human hepatocytes (PHHs) undergo dedifferentiation upon the two-dimensional (2D) culture, which particularly hinders their utility in long-term in vitro studies. Lipids, as a major class of biomolecules, play crucial roles in cellular energy storage, structure, and signaling. Here, for the first time, we mapped the alterations in the lipid profile of the dedifferentiating PHHs and studied the possible role of lipids in the loss of the phenotype of PHHs. Simultaneously, differentially expressed miRNAs associated with changes in the lipids and fatty acids (FAs) of the dedifferentiating PHHs were investigated. METHODS: PHHs were cultured in monolayer and their phenotype was monitored morphologically, genetically, and biochemically for five days. The lipid and miRNA profile of the PHHs were analyzed by mass spectrometry and Agilent microarray, respectively. In addition, 24 key genes involved in the metabolism of lipids and FAs were investigated by qPCR. RESULTS: The typical morphology of PHHs was lost from day 3 onward. Additionally, ALB and CYP genes were downregulated in the cultured PHHs. Lipidomics revealed a clear increase in the saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) containing lipids, but a decrease in the polyunsaturated fatty acids (PUFA) containing lipids during the dedifferentiation of PHHs. In line with this, FASN, SCD, ELOVL1, ELOVL3, and ELOVL7 were upregulated but ELOVL2 was downregulated in the dedifferentiated PHHs. Furthermore, differentially expressed miRNAs were identified, and the constantly upregulated miR-27a and miR-21, and downregulated miR-30 may have regulated the synthesis, accumulation and secretion of PHH lipids during the dedifferentiation. CONCLUSION: Our results showed major alterations in the molecular lipid species profiles, lipid-metabolizing enzyme expression as wells as miRNA profiles of the PHHs during their prolonged culture, which in concert could play important roles in the PHHs' loss of phenotype. These findings promote the understanding from the dedifferentiation process and could help in developing optimal culture conditions, which better meet the needs of the PHHs and support their original phenotype.


Assuntos
Desdiferenciação Celular , Hepatócitos/citologia , Metabolismo dos Lipídeos , MicroRNAs/genética , Acetiltransferases/genética , Acetiltransferases/metabolismo , Células Cultivadas , Citocromos/genética , Citocromos/metabolismo , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintase Tipo I/metabolismo , Hepatócitos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Albumina Sérica Humana/genética , Albumina Sérica Humana/metabolismo , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Regulação para Cima
12.
EBioMedicine ; 45: 155-167, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31235426

RESUMO

BACKGROUND: With the development of RNA-seq technology, tens of thousands of circular RNAs (circRNAs), a novel class of RNAs, have been identified. However, little is known about circRNA formation and biogenesis in hepatocellular carcinoma (HCC). METHODS: We performed ribosomal-depleted RNA-seq profiling of HCC and para-carcinoma tissues and analyzed the expression of a hotspot circRNA derived from the 3'UTR of the stearoyl-CoA desaturase (SCD) gene, termed SCD-circRNA 2. FINDINGS: It was significantly upregulated in HCC and correlated with poor patient prognosis. Moreover, we observed that the production of SCD-circRNA 2 was dynamically regulated by RNA-binding protein 3 (RBM3). RBM3 overexpression was indicative of a short recurrence-free survival and poor overall survival for HCC patients. Furthermore, by modulating the RBM3 or SCD-circRNA 2 levels, we found that RBM3 promoted the HCC cell proliferation in a SCD-circRNA 2 dependent manner. INTERPRETATION: Herein, we report that RBM3 is crucial for the SCD-circRNA 2 formation in HCC cells, which not only provides mechanistic insights into cancer-related circRNA dysregulation but also establishes RBM3 as an oncogene with both therapeutic potential and prognostic value. FUND: This work was supported by the National Key Research and Development Program of China (2016YFC1302303), the National Natural Science Foundation of China (Grant No. 81672345 and 81,402,269). The funders did not have any roles in study design, data collection, data analysis, interpretation, writing of the report.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Proteínas de Ligação a RNA/genética , Estearoil-CoA Dessaturase/genética , Idoso , Carcinoma Hepatocelular/patologia , Proliferação de Células/genética , China , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/patologia , Masculino , MicroRNAs , Pessoa de Meia-Idade , Prognóstico
13.
Bull Exp Biol Med ; 167(2): 263-266, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31243677

RESUMO

We studied the expression of genes encoding enzymes of carbohydrate and lipid metabolism ketohexokinase (Khk), glucokinase (Gck), pyruvate kinase (Pklr), acetyl-Co-carboxylase (Acaca), fatty acid synthase (Fasn), stearoyl-CoA desaturase (Scd), and their transcription regulators ChREBP (Mlxipl), SREBP-1c (Srebf1), and PPARα (Ppara) in rat liver. Control group rats received a semisynthetic ration over 20 weeks. Experimental group 1 received a semisynthetic ration and 20% fructose solution instead of drinking water. Experimental group 2 rats received a semisynthetic ration with quercetin (0.1% fodder weight) and 20% fructose solution. Consumption of 20% fructose solution (experimental group 1) led to an increase in Scd expression in comparison with the control and did not affect the expression of other genes. Addition of quercetin to the ration (experimental group 2) led to a decrease in the expression of Khk, Gck, Fasn, Scd, Mlxipl, and Ppara genes in comparison with experimental group 1. The results suggest that quercetin reduced the expression of genes of carbohydrate and lipid metabolism enzymes in the liver of rats receiving high-fructose ration.


Assuntos
Enzimas/genética , Frutose/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Quercetina/farmacologia , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Metabolismo dos Carboidratos/efeitos dos fármacos , Metabolismo dos Carboidratos/genética , Dieta , Enzimas/metabolismo , Frutoquinases/genética , Frutoquinases/metabolismo , Glucoquinase/genética , Glucoquinase/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Masculino , Piruvato Quinase/genética , Piruvato Quinase/metabolismo , Ratos , Ratos Wistar , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
14.
Acta Biochim Biophys Sin (Shanghai) ; 51(6): 615-626, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31139819

RESUMO

Few information of the function of stearoyl-coenzyme A (CoA) desaturase (SCD) in apicomplaxan parasite has been obtained. In this study, we retrieved a putative fatty acyl-CoA desaturase (TGGT1_238950) by a protein alignment with Plasmodium falciparum SCD in ToxoDB. A typical Δ9-desaturase domain was revealed in this protein. The putative desaturase was tagged with HA endogenously in Toxoplasma gondii, and the endoplasmic reticulum localization of the putative desaturase was revealed, which was consistent with the fatty acid desaturases in other organisms. Therefore, the TGGT1_238950 was designated T. gondii SCD. Based on CRISPR/Cas9 gene editing technology, SCD conditional knockout mutants in the T. gondii TATi strain were obtained. The growth in vitro and pathogenicity in mice of the mutants suggested that SCD might be dispensable for tachyzoite growth and proliferation. The SCD-overexpressing line was constructed to further explore SCD function. The portion of palmitoleic acid and oleic acid were increased in SCD-overexpressing parasites, compared with the RH parental strain, indicating that T. gondii indeed is competent for unsaturated fatty acid synthesis. The SCD-overexpressing tachyzoites propagated slower than the parental strain, with a decreased invasion capability and weaker pathogenicity in mice. The TgIF2α phosphorylation and the expression changes of several genes demonstrated that ER stress was triggered in the SCD-overexpressing parasites, which were more apt toward autophagy and apoptosis. The function of unsaturated fatty acid synthesis of TgSCD was consistent with our hypothesis. On the other hand, SCD might also be involved in tachyzoite autophagy and apoptosis.


Assuntos
Proteínas de Protozoários/imunologia , Estearoil-CoA Dessaturase/imunologia , Toxoplasma/enzimologia , Toxoplasmose/imunologia , Animais , Células Cultivadas , Clonagem Molecular , Humanos , Camundongos Endogâmicos BALB C , Mutação , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Análise de Sequência de DNA , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Análise de Sobrevida , Toxoplasma/genética , Toxoplasma/patogenicidade , Toxoplasmose/parasitologia
15.
Int J Mol Sci ; 20(11)2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31142011

RESUMO

Nonalcoholic fatty liver disease is a frequent liver malady, which can progress to cirrhosis, the end-stage liver disease if proper treatment is not applied. Omega-3 fatty acids, such as docosahexaenoic acid (DHA) and eicosapentaenoic acid, have been clinically proven to lower serum triglyceride levels. Various physiological activities of omega-3 fatty acids are due to their agonistic actions on G-protein-coupled receptor 40 (GPR40) and GPR120. Lipid droplets (LD) accumulation in hepatocytes confirmed that DHA treatment reduced the number of larger ( >10 µm2) LDs, as well as the total area of LDs. Moreover, DHA lowered protein and mRNA expression levels of lipogenic enzymes such as fatty acid synthase (FAS), acetyl-CoA carboxylase and stearoyl-CoA desaturase-1 (SCD-1) in primary hepatocytes incubated with liver X receptor (LXR) agonist T0901317 or high glucose and insulin. DHA also decreased protein expression of nuclear and precursor sterol response-element binding protein (SREBP)-1, a key lipogenesis transcription factor. We further found that exposure of murine primary hepatocytes to DHA for 12 h increased GPR40 and GPR120 mRNA levels. Specific agonists (Compound A for GPR120 and AMG-1638 for GPR40), hepatocytes from GPR120 knock-out mice and GPR40 selective antagonist (GW1100) were used to assess whether DHA's antilipogenic effects are mediated through GPR120 or GPR40. Compound A did not decrease SREBP-1 and FAS protein expression in hepatocytes exposed to T0901317 or high glucose with insulin. Moreover, DHA downregulated lipogenesis enzyme expression in GPR120-null hepatocytes. In contrast, AMG-1638 lowered SREBP-1 and SCD-1 protein levels. Additionally, GW1100, a GPR40 antagonist, reversed the antilipogenic effects of DHA. Collectively, our data demonstrate that DHA downregulates the expression SREBP-1-mediated lipogenic enzymes via GPR40 in primary hepatocytes.


Assuntos
Ácidos Docosa-Hexaenoicos/farmacologia , Hepatócitos/metabolismo , Lipogênese , Receptores Acoplados a Proteínas-G/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Animais , Células Cultivadas , Ácidos Graxos Ômega-3/metabolismo , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Receptores Acoplados a Proteínas-G/antagonistas & inibidores , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Receptor fas/genética , Receptor fas/metabolismo
16.
Molecules ; 24(6)2019 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-30884812

RESUMO

Phenolic compounds might modulate adiposity. Here, we report our observation that polyphenols and phenolic acids inhibit adipogenesis in 3T3-L1 with different intensity depending on the family and the stage of differentiation. While quercetin and resveratrol inhibited lipid accumulation along the whole process of differentiation, apigenin and myricetin were active during the early and latest stages, but not intermediate, contrary to hesperidin. The activity of phenolic acids was limited to the early stages of the differentiation process, except p-coumaric and ellagic acids. This anti-adipogenic effect was accompanied by down-regulation of Scd1 and Lpl. Molecular docking analysis revealed that the inhibitory activity of these phenolic compounds over the early stages of adipogenesis exhibits a significant correlation (r = 0.7034; p = 0.005) with their binding affinity to the ligand-binding domain of PPARγ. Results show that polyphenols and phenolic acids would interact with specific residues of the receptor, which could determine their potential anti-adipogenic activity during the early stages of the differentiation. Residues Phe264, His266, Ile281, Cys285 and Met348 are the most frequently involved in these interactions, which might suggest a crucial role for these amino acids modulating the activity of the receptor. These data contribute to elucidate the possible mechanisms of phenolic compounds in the control of adipogenesis.


Assuntos
Adipogenia/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , PPAR gama/genética , Fenóis/farmacologia , Células 3T3-L1 , Adipogenia/genética , Animais , Apigenina/química , Apigenina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Flavonoides/química , Flavonoides/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Hesperidina/química , Hesperidina/farmacologia , Camundongos , Simulação de Acoplamento Molecular , PPAR gama/metabolismo , Fenóis/química , Quercetina/química , Quercetina/farmacologia , Resveratrol/química , Resveratrol/farmacologia , Estearoil-CoA Dessaturase/genética
17.
J Med Food ; 22(4): 325-336, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30864855

RESUMO

Nonalcoholic fatty liver disease is a progressive disease involving the accumulation of lipid droplets in the liver. In this study, we investigated the anti-hepatosteatosis effects of fermented Cordyceps militaris extract (CME) in AML-12 hepatocytes. Although the levels of adenosine and cordycepin were reduced in the extracts of CM grown on germinated soybean (GSCE) and fermented CM grown on germinated soybean (GSC) by Pediococcus pentosaceus ON188 (ON188E), the expression of fatty acid oxidation (FAO) genes were upregulated only by GSC-ON188E treatment in a dose-dependent manner. In contrast, a lipogenic gene, stearoyl Coenzyme A desaturase 1, was downregulated by ON188E. Formation of intracellular lipid droplets by the addition of oleic acid was reduced by ON188E to levels observed in WY14643-treated cells. When cells were treated with ON188E, sphingosine kinase 2 mainly responsible for hepatic sphingosine 1-phosphate (S1P) synthesis was upregulated and S1P was elevated. Collectively, the fermented GSC extract activates FAO through elevation of S1P synthesis and has potential as a therapeutic for hepatosteatosis.


Assuntos
Cordyceps/química , Ácidos Graxos/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Extratos Vegetais/farmacologia , Animais , Linhagem Celular , Cordyceps/metabolismo , Fermentação , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Lisofosfolipídeos/metabolismo , Camundongos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/enzimologia , Hepatopatia Gordurosa não Alcoólica/genética , Oxirredução/efeitos dos fármacos , Pediococcus pentosaceus/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo
18.
PLoS One ; 14(3): e0214294, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30913248

RESUMO

Metabolic reprogramming is considered a hallmark of cancer. Currently, the altered lipid metabolism in cancer is a topic of interest due to the prominent role of lipids regulating the progression of various types of tumors. Lipids and lipid-derived molecules have been shown to activate growth regulatory pathways and to promote malignancy in pancreatic cancer. In a previous work, we have described the antitumoral properties of Yarrow (Achillea Millefolium) CO2 supercritical extract (Yarrow SFE) in pancreatic cancer. Herein, we aim to investigate the underlaying molecular mechanisms by which Yarrow SFE induces cytotoxicity in pancreatic cancer cells. Yarrow SFE downregulates SREBF1 and downstream molecular targets of this transcription factor, such as fatty acid synthase (FASN) and stearoyl-CoA desaturase (SCD). Importantly, we demonstrate the in vivo effect of Yarrow SFE diminishing the tumor growth in a xenograft mouse model of pancreatic cancer. Our data suggest that Yarrow SFE can be proposed as a complementary adjuvant or nutritional supplement in pancreatic cancer therapy.


Assuntos
Achillea/química , Antineoplásicos Fitogênicos/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Extratos Vegetais/química , Achillea/metabolismo , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Ácido Graxo Sintases/genética , Ácido Graxo Sintases/metabolismo , Humanos , Masculino , Camundongos , Camundongos Nus , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/antagonistas & inibidores , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Transplante Heterólogo
19.
J Exp Clin Cancer Res ; 38(1): 116, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30845964

RESUMO

BACKGROUND: Angiotensin II (ANGII) and its receptor (AGTR1) have been proposed as significant contributors to metastasis in multiple cancers. Further, high AGTR1 levels are associated with poor epithelial ovarian cancer (EOC) outcomes. However, the mechanistic basis for these effects is unknown. Recent studies have suggested that ovarian cancer metastasis is highly dependent on the formation of multicellular spheroids (MCS). To understand the associations between the ANGII/AGTR1 pathway and cancer outcomes, we evaluated the effects of ANGII on MCS formation by ovarian cancer cells and used a proteomic approach to analyze the mechanistic basis. METHODS: We used the data from the GENT database and immunohistochemistry staining to assess the AGTR1 expression in epithelial ovarian cancer (EOC) patients and to assess its role in cancer progression. Colony formation assay, 3D culture assay, and transwell assays were used to analyze the effect of ANGII on the MCS formation and cell migration. The signaling pathways of AGTR1 and transactivation of epidermal growth factor receptor (EGFR) transactivation were investigated by the western blotting analysis. Xenograft models were used to determine the role of AGTR1 in ovarian cancer metastasis. ANGII release from ovarian cancer cells and ANGII levels in the EOC ascites fluid were measured by immunoassay. A shotgun proteomic approach was used to explore the detail molecular mechanism. Modulation of lipid desaturation and endoplasmic reticulum stress were verified by the in vitro and in vivo functional assays. RESULTS: AGTR1 expression was negatively correlated with EOC prognosis. AGTR1activation significantly enhanced the MCS formation and cell migration. ANGII triggered both of the classical AGTR1 pathway and the EGFR transactivation. ANGII administration increased peritoneal metastasis. In addition, ovarian cancer cells secreted ANGII and enhanced cancer metastasis in a positive feedback manner. Based on the proteomic data, lipid desaturation was activated by induction of stearoyl-CoA desaturase-1 (SCD1), which suggests that inhibition of SCD1 may significantly reduce MCS formation by increasing endoplasmic reticulum stress. CONCLUSIONS: ANGII promotes MCS formation and peritoneal metastasis of EOC cells. AGTR1 activation increases the lipid desaturation via SCD1 upregulation, which ultimately reduces endoplasmic reticulum stress in MCS. This mechanism explained the association between high levels of AGTR1 and poor clinical outcomes in EOC patients.


Assuntos
Carcinoma Epitelial do Ovário/genética , Neoplasias Peritoneais/genética , Receptor Tipo 1 de Angiotensina/genética , Estearoil-CoA Dessaturase/genética , Angiotensina II/genética , Angiotensina II/metabolismo , Animais , Carcinoma Epitelial do Ovário/patologia , Movimento Celular/genética , Estresse do Retículo Endoplasmático/genética , Receptores ErbB/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Metabolismo dos Lipídeos/genética , Lipídeos/genética , Camundongos , Metástase Neoplásica , Neoplasias Peritoneais/patologia , Neoplasias Peritoneais/secundário , Prognóstico , Proteômica , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
20.
J Exp Clin Cancer Res ; 38(1): 96, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30791926

RESUMO

BACKGROUND: Drug resistance is common in cancer chemotherapy. This study investigates the role of Glycerol kinase 5 (GK5) in mediating gefitinib resistance in NSCLC. METHODS: The exosomal mRNA of GK5 was detected using a tethered cationic lipoplex nanoparticle (TCLN) biochip. Real-time PCR and Western blot were used to examine the expression of GK5 mRNA and protein in gefitinib-sensitive and -resistant human lung adenocarcinoma cells. The cell counting kit-8, EdU assay, flow cytometry, and JC-1 dye were used to measure cell proliferation, cell cycle, and the mitochondrial membrane potential. RESULTS: We found that the exosomal mRNA of GK5 in the plasma of patients with gefitinib-resistant adenocarcinoma was significantly higher compared with that of gefitinib-sensitive patients. The mRNA and protein levels of GK5 were significantly upregulated in gefitinib-resistant human lung adenocarcinoma PC9R and H1975 cells compared with gefitinib-sensitive PC9 cells. Silencing GK5 in PC9R cells induced mitochondrial damage, caspase activation, cell cycle arrest, and apoptosis via SREBP1/SCD1 signaling pathway. CONCLUSIONS: We demonstrated that GK5 confers gefitinib resistance in lung cancer by inhibiting apoptosis and cell cycle arrest. GK5 could be a novel therapeutic target for treatment of NSCLC with resistance to EGFR tyrosine kinase inhibitors.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Gefitinibe/farmacologia , Glicerol Quinase/genética , Transdução de Sinais/genética , Estearoil-CoA Dessaturase/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma de Pulmão/dietoterapia , Adenocarcinoma de Pulmão/genética , Animais , Antineoplásicos/farmacologia , Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Masculino , Potencial da Membrana Mitocondrial/genética , Camundongos , Camundongos Endogâmicos BALB C , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/farmacologia , RNA Mensageiro/genética , Regulação para Cima/genética
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