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1.
Molecules ; 27(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36432116

RESUMO

Primary liver cancer is the fifth leading death of cancers in men, and hepatocellular carcinoma (HCC) accounts for approximately 90% of all primary liver cancer cases. Sorafenib is a first-line drug for advanced-stage HCC patients. Sorafenib is a multi-target kinase inhibitor that blocks tumor cell proliferation and angiogenesis. Despite sorafenib treatment extending survival, some patients experience side effects, and sorafenib resistance does occur. 3-Hydroxymethyl glutaryl-CoA synthase 2 (HMGCS2) is the rate-limiting enzyme for ketogenesis, which synthesizes the ketone bodies, ß-hydroxybutyrate (ß-HB) and acetoacetate (AcAc). ß-HB is the most abundant ketone body which is present in a 4:1 ratio compared to AcAc. Recently, ketone body treatment was found to have therapeutic effects against many cancers by causing metabolic alternations and cancer cell apoptosis. Our previous publication showed that HMGCS2 downregulation-mediated ketone body reduction promoted HCC clinicopathological progression through regulating c-Myc/cyclin D1 and caspase-dependent signaling. However, whether HMGCS2-regulated ketone body production alters the sensitivity of human HCC to sorafenib treatment remains unclear. In this study, we showed that HMGCS2 downregulation enhanced the proliferative ability and attenuated the cytotoxic effects of sorafenib by activating expressions of phosphorylated (p)-extracellular signal-regulated kinase (ERK), p-P38, and p-AKT. In contrast, HMGCS2 overexpression decreased cell proliferation and enhanced the cytotoxic effects of sorafenib in HCC cells by inhibiting ERK activation. Furthermore, we showed that knockdown HMGCS2 exhibited the potential migratory ability, as well as decreasing zonula occludens protein (ZO)-1 and increasing c-Myc expression in both sorafenib-treated Huh7 and HepG2 cells. Although HMGCS2 overexpression did not alter the migratory effect, expressions of ZO-1, c-Myc, and N-cadherin decreased in sorafenib-treated HMGCS2-overexpressing HCC cells. Finally, we investigated whether ketone treatment influences sorafenib sensitivity. We showed that ß-HB pretreatment decreased cell proliferation and enhanced antiproliferative effect of sorafenib in both Huh7 and HepG2 cells. In conclusion, this study defined the impacts of HMGCS2 expression and ketone body treatment on influencing the sorafenib sensitivity of liver cancer cells.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Masculino , Humanos , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico , Carcinoma Hepatocelular/metabolismo , Hidroximetilglutaril-CoA Sintase/genética , Hidroximetilglutaril-CoA Sintase/metabolismo , Cetonas/uso terapêutico , Neoplasias Hepáticas/patologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Corpos Cetônicos/metabolismo , Corpos Cetônicos/uso terapêutico , MAP Quinases Reguladas por Sinal Extracelular , Resultado do Tratamento
2.
J Biotechnol ; 359: 29-34, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-36150604

RESUMO

Isopropanol has a good potential as a new fuel substitution. In the model biosynthesis pathway of isopropanol synthesis, acetoacetyl-CoA is converted to acetoacetate by acetoacetyl-CoA transferases, which requires an acetate molecule as a substrate. Herein, a novel isopropanol synthesis pathway based on mammalian ketone metabolic pathway was developed. In this pathway, acetoacetyl-CoA is condensed with acetyl-CoA to generate 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) by HMG-CoA synthase, and then catalyzed by HMG-CoA lyase to generate acetoacetate. This process is acetate-independent. Under the same experimental system using glycerol as carbon source, the E. coli strain MG::ISOP1 containing the novel pathway produced 11.7 times more isopropanol than the strain MG::ISOP0 containing the model pathway. The pta-ackA knockout mutant strain MG∆pta-ackA::ISOP1, which reduced the conversion of acetyl-CoA to acetate, further increased the production from 76 mg/L to 360 mg/L. In another strategy, knocking out atoDA to block the acetoacetate degradation pathway in strain MG∆atoDA::ISOP1 increased the production to 680 mg/L. By knocking out both of pta-ackA and atoDA, strain MGΔpta-ackAΔatoDA::ISOP1 produced 964 mg/L of isopropanol, which was 12.7 times that of MG::ISOP1. This study indicated that the novel pathway is competent for isopropanol synthesis, and provides a new perspective for biosynthesis of isopropanol.


Assuntos
2-Propanol , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , 2-Propanol/metabolismo , Acetoacetatos/metabolismo , Acetilcoenzima A/metabolismo , Coenzima A-Transferases/metabolismo , Hidroximetilglutaril-CoA Sintase/genética , Hidroximetilglutaril-CoA Sintase/metabolismo , Glicerol/metabolismo , Acetatos/metabolismo , Carbono/metabolismo
3.
Bioengineered ; 13(5): 11417-11429, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35506308

RESUMO

Diabetic cardiomyopathy (DCM) is a diabetic mellitus-related complications and progression of DCM may eventually lead to heart failure, while mechanisms related to DCM pathophysiology remain unclear. The study was undertaken to identify possible hub genes associated with DCM progression through bioinformatics analysis and to validate the role of 3-hydroxy-3-methylglutaryl-CoA synthase 2 (HMGCS2) in DCM progression using a cellular model of high glucose (HG)-induced DCM. The common differentially expressed genes (DEGs) between GSE173884 and GSE161827 were used for PPI network analysis. Our results identified 17 common DEGs between GSE173384 and GSE161827. Further analysis of the protein-protein interaction network identified nine hub genes and HMGCS2. The in vitro functional assays showed that HG induced up-regulation of HMGCS2, suppressed cardiomyocyte viability, enhanced apoptosis, inflammation, and oxidative stress of cardiomyocytes. Gain-of-function assays showed that HMGCS2 overexpression reduced cell viability, increased apoptosis, caspase-3/-9 activity, up-regulated interleukin (IL)-1ß, IL-6 and tumor necrosis factor-α (TNF-α) expression, decreased superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase expression, increased malondialdehyde (MDA) content, and reactive oxygen species (ROS) level but inhibited total antioxidant activity, SOD activity, CAT activity, and glutathione content in cardiomyocytes. Rescue experiments demonstrated HMGCS2 silence attenuated HG-induced decrease in cardiomyocyte viability and increase in cardiomyocyte apoptosis, inflammation, and oxidative stress. All in all, our study identified HMGCS2 as a hub gene in DCM pathophysiology and further functional studies indicated that HMGCS2 may aggravate DCM progression by reducing cardiomyocyte viability, increasing cardiomyocyte apoptosis, and promoting inflammation and oxidative stress in cardiomyocytes.


Assuntos
Diabetes Mellitus , Cardiomiopatias Diabéticas , Antioxidantes , Apoptose/genética , Sobrevivência Celular/genética , Cardiomiopatias Diabéticas/genética , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/patologia , Glucose/toxicidade , Humanos , Hidroximetilglutaril-CoA Sintase/metabolismo , Inflamação/genética , Inflamação/patologia , Estresse Oxidativo , Superóxido Dismutase/metabolismo
4.
Mol Metab ; 61: 101494, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35421611

RESUMO

OBJECTIVE: Aberrant ketogenesis is correlated with the degree of steatosis in non-alcoholic fatty liver disease (NAFLD) patients, and an inborn error of ketogenesis (mitochondrial HMG-CoA synthase deficiency) is commonly associated with the development of the fatty liver. Here we aimed to determine the impact of Hmgcs2-mediated ketogenesis and its modulations on the development and treatment of fatty liver disease. METHODS: Loss- and gain-of-ketogenic function models, achieved by Hmgcs2 knockout and overexpression, respectively, were utilized to investigate the role of ketogenesis in the hepatic lipid accumulation during postnatal development and in a high-fat diet-induced NAFLD mouse model. RESULTS: Ketogenic function was decreased in NAFLD mice with a reduction in Hmgcs2 expression. Mice lacking Hmgcs2 developed spontaneous fatty liver phenotype during postnatal development, which was rescued by a shift to a low-fat dietary composition via early weaning. Hmgcs2 heterozygous adult mice, which exhibited lower ketogenic activity, were more susceptible to diet-induced NAFLD development, whereas HMGCS2 overexpression in NAFLD mice improved hepatosteatosis and glucose homeostasis. CONCLUSIONS: Our study adds new knowledge to the field of ketone body metabolism and shows that Hmgcs2-mediated ketogenesis modulates hepatic lipid regulation under a fat-enriched nutritional environment. The regulation of hepatic ketogenesis may be a viable therapeutic strategy in the prevention and treatment of hepatosteatosis.


Assuntos
Dieta Hiperlipídica , Hidroximetilglutaril-CoA Sintase , Cetose , Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Hiperlipídica/efeitos adversos , Humanos , Hidroximetilglutaril-CoA Sintase/genética , Hidroximetilglutaril-CoA Sintase/metabolismo , Corpos Cetônicos/genética , Corpos Cetônicos/metabolismo , Cetose/genética , Cetose/metabolismo , Lipídeos , Camundongos , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo
5.
Am J Physiol Renal Physiol ; 322(4): F460-F467, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35224990

RESUMO

Mitochondrial hydroxymethylglutaryl-CoA synthase 2 (HMGCS2) is the rate-limiting enzyme in ketogenesis. The liver expresses high levels of HMGCS2 constitutively as the main ketogenic organ. It has been suggested that the kidney could be ketogenic as HMGCS2 is expressed in the kidney during fasting and diabetic conditions. However, definitive proof of the capacity for the kidney to produce ketones is lacking. We demonstrated that during fasting, HMGCS2 expression is induced in the proximal tubule of the kidney and is peroxisome proliferator activated receptor-α dependent. Mice with kidney-specific Hmgcs2 deletion showed a minor, likely physiologically insignificant, decrease in circulating ketones during fasting. Conversely, liver-specific Hmgcs2 knockout mice exhibited a complete loss of fasting ketosis. Together, these findings indicate that renal HMGCS2 does not significantly contribute to global ketone production and that during fasting, the increase in circulating ketones is solely dependent on hepatic HMGCS2. Proximal tubule HMGCS2 serves functions other than systemic ketone provision.NEW & NOTEWORTHY The mitochondrial enzyme hydroxymethylglutaryl-CoA synthase 2 (HMGCS2) catalyzes the rate-limiting step of ketogenesis. Although the liver constitutively expresses HMGCS2 and is considered the main ketogenic organ, HMGCS2 is induced in the kidney during fasting, leading to the proposal that the kidney contributes to fasting ketosis. We showed kidney HMGCS2 does not contribute to circulating ketones during fasting and cannot compensate for hepatic ketogenic insufficiency.


Assuntos
Hidroximetilglutaril-CoA Sintase/metabolismo , Cetose , Animais , Jejum , Hidroximetilglutaril-CoA Sintase/genética , Corpos Cetônicos/metabolismo , Cetonas , Cetose/metabolismo , Rim/metabolismo , Camundongos
6.
J Invest Dermatol ; 142(3 Pt A): 539-548, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34454908

RESUMO

Three-hydroxy-3-methylglutaryl coenzyme A synthase (HMGCS) 1 was identified to interact with Gal-7, a pro-apoptotic ß-galactoside‒binding protein, by yeast two-hybrid system. Their interaction was confirmed by in vitro ß-galactosidase, Biacore, and immunoprecipitation assays. A distinct interactive site of HMGCS1 was found to reside at phenylalanine 26. The expression of HMGCS1 in cultured keratinocytes was upregulated by exogenous Gal-7 and downregulated in LGALS7 small interfering RNA‒transfected cells. HMGCS1-overexpressing cells were found to induce Gal-7 expression, which suggests that Gal-7 and HMGCS1 expressions are both stimulated by positive feedback regulation. The amount of cholesterol, a final biosynthetic product of HMGCS1-involved pathway, was increased in Gal-7‒treated cells and was significantly reduced in LGALS7 small interfering RNA‒transfected cells. The increase of cholesterol level in Gal-7‒treated cells was inhibited by wild-type HMGCS1 peptide but not by phenylalanine 26‒mutated peptide, suggesting that the interaction of Gal-7/HMGCS1 is related to cellular cholesterol level. Foam cells in granulomatous tissues of the specimens from normolipidemic cutaneous xanthoma showed positive reactions with the antibodies for Gal-7 and HMGCS1 as well as for lipid markers. These results are likely to indicate that Gal-7 induction in epidermal keratinocytes causes both apoptotic cell death and HMGCS1-mediated cholesterol accumulation, which will be phagocytized by macrophages. This mechanism may explain the pathogenesis of normolipidemic cutaneous xanthoma.


Assuntos
Hidroximetilglutaril-CoA Sintase , Xantomatose , Colesterol/metabolismo , Galectinas , Humanos , Hidroximetilglutaril-CoA Sintase/metabolismo , Queratinócitos/metabolismo , Fenilalanina , RNA Interferente Pequeno
7.
Cancer Rep (Hoboken) ; 5(9): e1562, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34549901

RESUMO

BACKGROUND: Emerging studies reveals that 3-hydroxy-3-methylglutaryl-CoA synthase 1 (HMGCS1) plays vital oncogenic roles in a broad spectrum of human cancers, but there is no pan-cancer evidence on the relationship between HMGCS1 and various tumor types. AIM: To explore the potential role of HMGCS1 across various tumor types based on big clinical data. METHODS: We conducted a pan-cancer analysis across more than 30 tumor types, based on the most comprehensive database available, including TCGA, GSCA, clinical proteomic tumor analysis consortium, Kaplan-Meier Plotter dataset, GEPIA2, TIMER2, STRING, and GDSC dataset. RESULTS: HMGCS1 was highly expressed and negatively correlated with the prognosis in most cancer types. The infiltration levels of cancer associated fibroblast and CD8+ T-cell were closely associated with HMGCS1 expression. Amplification was the most common genetic alteration of HMGCS1 in different cancers, while the frequency of mutation was low. Besides, ACAT2 and MVD were closely correlated and bind to HMGCS1. Pathway enrichment analysis indicated that HMGCS1 was actively involved in steroid biosynthesis. Moreover, high HMGCS1 expression could reduce the sensitivity to most drugs in the GDSC dataset. CONCLUSIONS: Our study revealed the potential oncogenic role of HMGCS1 in cancers.


Assuntos
Hidroximetilglutaril-CoA Sintase/metabolismo , Proteômica , Acil Coenzima A , Carcinogênese/genética , Linhagem Celular Tumoral , Humanos , Hidroximetilglutaril-CoA Sintase/genética
8.
Cells ; 10(12)2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34944058

RESUMO

BACKGROUND: PXR is a xenobiotic-responsive nuclear receptor that controls the expression of drug-metabolizing enzymes. Drug-induced activation of PXR sometimes causes drug-drug interactions due to the induced metabolism of co-administered drugs. Our group recently reported a possible drug-drug interaction mechanism via an interaction between the nuclear receptors CAR and PPARα. As CAR and PXR are structurally and functionally related receptors, we investigated possible crosstalk between PXR and PPARα. METHODS: Human hepatocyte-like HepaRG cells were treated with various PXR ligands, and mRNA levels were determined by quantitative reverse transcription PCR. Reporter assays using the HMGCS2 promoter containing a PPARα-binding motif and mammalian two-hybrid assays were performed in HepG2 or COS-1 cells. RESULTS: Treatment with PXR activators reduced the mRNA levels of PPARα target genes in HepaRG cells. In reporter assays, PXR suppressed PPARα-dependent gene expression in HepG2 cells. In COS-1 cells, co-expression of PGC1α, a common coactivator of PPARα and PXR, enhanced PPARα-dependent gene transcription, which was clearly suppressed by PXR. Consistently, in mammalian two-hybrid assays, the interaction between PGC1α and PPARα was attenuated by ligand-activated PXR. CONCLUSION: The present results suggest that ligand-activated PXR suppresses PPARα-dependent gene expression by inhibiting PGC1α recruitment.


Assuntos
Hidroximetilglutaril-CoA Sintase/genética , PPAR alfa/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Receptor de Pregnano X/genética , Regulação da Expressão Gênica , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Fígado/metabolismo , Regiões Promotoras Genéticas/genética , Transcrição Genética/genética , Xenobióticos/metabolismo
9.
J Cell Biol ; 220(9)2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34347016

RESUMO

Cholesterol metabolism operates autonomously within the central nervous system (CNS), where the majority of cholesterol resides in myelin. We demonstrate that TDP-43, the pathological signature protein for amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), influences cholesterol metabolism in oligodendrocytes. TDP-43 binds directly to mRNA of SREBF2, the master transcription regulator for cholesterol metabolism, and multiple mRNAs encoding proteins responsible for cholesterol biosynthesis and uptake, including HMGCR, HMGCS1, and LDLR. TDP-43 depletion leads to reduced SREBF2 and LDLR expression, and cholesterol levels in vitro and in vivo. TDP-43-mediated changes in cholesterol levels can be restored by reintroducing SREBF2 or LDLR. Additionally, cholesterol supplementation rescues demyelination caused by TDP-43 deletion. Furthermore, oligodendrocytes harboring TDP-43 pathology from FTD patients show reduced HMGCR and HMGCS1, and coaggregation of LDLR and TDP-43. Collectively, our results indicate that TDP-43 plays a role in cholesterol homeostasis in oligodendrocytes, and cholesterol dysmetabolism may be implicated in TDP-43 proteinopathies-related diseases.


Assuntos
Colesterol/metabolismo , Proteínas de Ligação a DNA/genética , Demência Frontotemporal/genética , Bainha de Mielina/metabolismo , Oligodendroglia/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Animais , Proteínas de Ligação a DNA/deficiência , Modelos Animais de Doenças , Feminino , Lobo Frontal/metabolismo , Lobo Frontal/patologia , Demência Frontotemporal/metabolismo , Demência Frontotemporal/patologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Hidroximetilglutaril-CoA Sintase/genética , Hidroximetilglutaril-CoA Sintase/metabolismo , Metabolismo dos Lipídeos/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Bainha de Mielina/patologia , Oligodendroglia/patologia , Organoides/metabolismo , Organoides/patologia , Cultura Primária de Células , Receptores de LDL/genética , Receptores de LDL/metabolismo , Transdução de Sinais , Medula Espinal/metabolismo , Medula Espinal/patologia , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Lobo Temporal/metabolismo , Lobo Temporal/patologia
10.
Sci Prog ; 104(3): 368504211031749, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34260294

RESUMO

This integrated bioinformatic study aimed to investigate potential prognostic candidates in hepatocellular carcinoma (HCC). In the GSE14520, GSE101685, and The Cancer Genome Atlas (TCGA) datasets, differentially expressed genes (DEGs) were identified and functional pathways of common DEGs were enriched. The least absolute shrinkage and selection operator (LASSO) model was used to screen the potential parameters associated with overall survival (OS) in HCC patients. Metabolic pathways were the most significantly enriched functional pathways of common DEGs in these three datasets. After LASSO model analysis, HMGCS2, UGP2, BCLC staging and TNM staging were screened as potential prognostic candidates for OS in HCC patients in GSE14520. HMGCS2 in the metabolic pathway was significantly downregulated in tumor tissues and peripheral blood mononuclear cells in HCC patients (all p < 0.05). Cox regression model indicated that HMGCS2 might be associate with OS in HCC patients in GSE14520 and in the TCGA (p = 0.029 and p = 0.05, respectively). Kaplan-Meier analysis demonstrated that HMGCS2 downregulation in tumors contributed to an unfavorable OS in HCC patients, both in GSE14520 and in the TCGA (p = 0.0001 and p = 0.0002, respectively). Additionally, HMGCS2 was significantly downregulated in HCC patients with high alpha-fetoprotein (AFP), main tumor size >5 cm, multinodular, advanced tumor staging including BCLC, TNM and CLIP (all p < 0.05). HMGCS2 was involved in metabolic pathways, and downregulated HMGCS2 in tumors was associated with unfavorable OS in HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Perfilação da Expressão Gênica , Humanos , Hidroximetilglutaril-CoA Sintase/metabolismo , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Redes e Vias Metabólicas/genética
12.
Br J Cancer ; 125(6): 865-876, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34274945

RESUMO

BACKGROUND: Many molecular alterations are shared by embryonic liver development and hepatocellular carcinoma (HCC). Identifying the common molecular events would provide a novel prognostic biomarker and therapeutic target for HCC. METHODS: Expression levels and clinical relevancies of SLC38A4 and HMGCS2 were investigated by qRT-PCR, western blot, TCGA and GEO datasets. The biological roles of SLC38A4 were investigated by functional assays. The downstream signalling pathway of SLC38A4 was investigated by qRT-PCR, western blot, immunofluorescence, luciferase reporter assay, TCGA and GEO datasets. RESULTS: SLC38A4 silencing was identified as an oncofetal molecular event. DNA hypermethylation contributed to the downregulations of Slc38a4/SLC38A4 in the foetal liver and HCC. Low expression of SLC38A4 was associated with poor prognosis of HCC patients. Functional assays demonstrated that SLC38A4 depletion promoted HCC cellular proliferation, stemness and migration, and inhibited HCC cellular apoptosis in vitro, and further repressed HCC tumorigenesis in vivo. HMGCS2 was identified as a critical downstream target of SLC38A4. SLC38A4 increased HMGCS2 expression via upregulating AXIN1 and repressing Wnt/ß-catenin/MYC axis. Functional rescue assays showed that HMGCS2 overexpression reversed the oncogenic roles of SLC38A4 depletion in HCC. CONCLUSIONS: SLC38A4 downregulation was identified as a novel oncofetal event, and SLC38A4 was identified as a novel tumour suppressor in HCC.


Assuntos
Sistema A de Transporte de Aminoácidos/genética , Sistema A de Transporte de Aminoácidos/metabolismo , Carcinoma Hepatocelular/patologia , Regulação para Baixo , Hidroximetilglutaril-CoA Sintase/metabolismo , Neoplasias Hepáticas/patologia , Fígado/embriologia , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Fígado/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Transplante de Neoplasias , Prognóstico , Proteínas Proto-Oncogênicas c-myc/metabolismo , Via de Sinalização Wnt
13.
Free Radic Biol Med ; 172: 90-100, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34087430

RESUMO

The disturbance of strictly regulated self-regeneration in mammalian intestinal epithelium is associated with various intestinal disorders, particularly inflammatory bowel diseases (IBDs). TNFα, which plays a critical role in the pathogenesis of IBDs, has been reported to inhibit production of ketone bodies such as ß-hydroxybutyrate (ßHB). However, the role of ketogenesis in the TNFα-mediated pathological process is not entirely known. Here, we showed the regulation and role of HMGCS2, the rate-limiting enzyme of ketogenesis, in TNFα-induced apoptotic and inflammatory responses in intestinal epithelial cells. Treatment with TNFα dose-dependently decreased protein and mRNA expression of HMGCS2 and its product, ßHB production in human colon cancer cell lines HT29 and Caco2 cells and mouse small intestinal organoids. Moreover, the repressed level of HMGCS2 protein was found in intestinal epithelium of IBD patients with Crohn's disease and ulcerative colitis as compared with normal tissues. Furthermore, knockdown of HMGCS2 enhanced and in contrast, HMGCS2 overexpression attenuated, the TNFα-induced apoptosis and expression of pro-inflammatory chemokines (CXCL1-3) in HT29, Caco2 cells and DLD1 cells, respectively. Treatment with ßHB or rosiglitazone, an agonist of PPARγ, which increases ketogenesis, attenuated TNFα-induced apoptosis in the intestinal epithelial cells. Finally, HMGCS2 knockdown enhanced TNFα-induced reactive oxygen species (ROS) generation. In addition, hydrogen peroxide, the major ROS contributing to intestine injury, decreased HMGCS2 expression and ßHB production in the intestinal cells and mouse organoids. Our findings demonstrate that increased ketogenesis attenuates TNFα-induced apoptosis and inflammation in intestinal cells, suggesting a protective role for ketogenesis in TNFα-induced intestinal pathologies.


Assuntos
Hidroximetilglutaril-CoA Sintase , Fator de Necrose Tumoral alfa , Animais , Apoptose , Células CACO-2 , Humanos , Mucosa Intestinal , Corpos Cetônicos , Camundongos , Fator de Necrose Tumoral alfa/genética
14.
J Hepatol ; 75(2): 363-376, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33887357

RESUMO

BACKGROUND & AIMS: Cholangiocarcinoma (CCA) is a neoplasia of the biliary tract driven by genetic, epigenetic and transcriptional mechanisms. Herein, we investigated the role of the transcription factor FOSL1, as well as its downstream transcriptional effectors, in the development and progression of CCA. METHODS: FOSL1 was investigated in human CCA clinical samples. Genetic inhibition of FOSL1 in human and mouse CCA cell lines was performed in in vitro and in vivo models using constitutive and inducible short-hairpin RNAs. Conditional FOSL1 ablation was done using a genetically engineered mouse (GEM) model of CCA (mutant KRAS and Trp53 knockout). Follow-up RNA and chromatin immunoprecipitation (ChIP) sequencing analyses were carried out and downstream targets were validated using genetic and pharmacological inhibition. RESULTS: An inter-species analysis of FOSL1 in CCA was conducted. First, FOSL1 was found to be highly upregulated in human and mouse CCA, and associated with poor patient survival. Pharmacological inhibition of different signalling pathways in CCA cells converged on the regulation of FOSL1 expression. Functional experiments showed that FOSL1 is required for cell proliferation and cell cycle progression in vitro, and for tumour growth and tumour maintenance in both orthotopic and subcutaneous xenograft models. Likewise, FOSL1 genetic abrogation in a GEM model of CCA extended mouse survival by decreasing the oncogenic potential of transformed cholangiocytes. RNA and ChIP sequencing studies identified direct and indirect transcriptional effectors such as HMGCS1 and AURKA, whose genetic and pharmacological inhibition phenocopied FOSL1 loss. CONCLUSIONS: Our data illustrate the functional and clinical relevance of FOSL1 in CCA and unveil potential targets amenable to pharmacological inhibition that could enable the implementation of novel therapeutic strategies. LAY SUMMARY: Understanding the molecular mechanisms involved in cholangiocarcinoma (bile duct cancer) development and progression stands as a critical step for the development of novel therapies. Through an inter-species approach, this study provides evidence of the clinical and functional role of the transcription factor FOSL1 in cholangiocarcinoma. Moreover, we report that downstream effectors of FOSL1 are susceptible to pharmacological inhibition, thus providing new opportunities for therapeutic intervention.


Assuntos
Colangiocarcinoma/genética , Hidroximetilglutaril-CoA Sintase/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/efeitos adversos , Idoso , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/etiologia , Feminino , Humanos , Hidroximetilglutaril-CoA Sintase/genética , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-fos/genética , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/genética
15.
Med Sci Monit ; 27: e929394, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33753712

RESUMO

BACKGROUND Bladder cancer is a malignant tumor of the genitourinary system. Different subtypes of bladder cancer have different treatment methods and prognoses. Therefore, identifying hub genes affecting other genes is of great significance for the treatment of bladder cancer. MATERIAL AND METHODS We obtained expression profiles from the GSE13507 and GSE77952 datasets from the Gene Expression Omnibus database. First, principal component analysis was used to identify the difference in gene expression in different types of tissues. Differential expression analysis was used to find the differentially expressed genes between normal and tumor tissues, and between tumors with and without muscle infiltration. Further, based on differentially expressed genes, we constructed 2 decision trees for differentiating between tumor and normal tissues, and between muscle-infiltrating and non-muscle-infiltrating tumor tissues. A receiver operating characteristic curve was used to evaluate the prediction effect of the decision trees. RESULTS FAM107A and C8orf4 showed significantly lower expression in bladder cancer tissues than in normal tissues. Regarding muscle infiltration, CTHRC1 showed lower expression and HMGCS2 showed higher expression in non-muscle-infiltrating samples than in those with muscle infiltration. We constructed 2 decision trees for differentiating between tumor and normal tissue, and between tissues with and without muscle infiltration. Both decision trees showed good prediction results. CONCLUSIONS These newly discovered hub genes will be helpful in understanding the occurrence and development of different subtypes of bladder cancer, and will provide new therapeutic targets and biomarkers for bladder cancer.


Assuntos
Neoplasias da Bexiga Urinária/classificação , Neoplasias da Bexiga Urinária/genética , Biomarcadores Tumorais/genética , Bases de Dados Genéticas , Árvores de Decisões , Proteínas da Matriz Extracelular/genética , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/genética , Genes Supressores de Tumor , Humanos , Hidroximetilglutaril-CoA Sintase/genética , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Análise de Componente Principal/métodos , Prognóstico , Curva ROC , Transcriptoma/genética
16.
Aging (Albany NY) ; 13(6): 8960-8974, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33647884

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease worldwide. Exercise is a therapeutic strategy for preventing NAFLD. However, the underlying molecular mechanisms by which NAFLD can be ameliorated through exercise are still not clear. This study investigates the mechanisms by which exercise suppresses NAFLD development induced by a high-fat diet (HFD) in mice. Male 6-week-old C57BL/6J mice were fed a normal diet or HFD for 12 weeks and then induced to swim or remain sedentary for 8 weeks. Histomorphology, inflammatory factors, fat metabolizing enzymes, fibrosis, and steatosis were determined in HFD-fed mouse liver, and levels of hepatic enzymes and molecules in the related pathways were analyzed. NAFLD mice showed evident steatosis, fibrosis, and liver injury, and an increased expression of HMGCS2, Wnt3a/ ß-catenin, and phosphorylated (p)-AMPK in the liver. Exercise significantly attenuated these symptoms and downregulated the level of Wnt3a/ß-catenin in lipotoxic liver tissue. Inhibition of HMGCS2 expression decreased the activation of the Wnt3a/ß-catenin pathway and lowered p-AMPK in palmitate-treated HepG2. Our results suggest that exercise prevents NAFLD-associated liver injury, steatosis, and fibrosis. Exercise-mediated hepatoprotection was achieved partly via the blocking of the upregulation of HMGCS2 and the attenuation of the Wnt3a/ß-catenin pathway.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Hidroximetilglutaril-CoA Sintase/metabolismo , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/terapia , Condicionamento Físico Animal/fisiologia , Adenilato Quinase/metabolismo , Animais , Modelos Animais de Doenças , Metabolismo dos Lipídeos/fisiologia , Camundongos , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fosforilação
17.
Biomed Pharmacother ; 137: 111378, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33601148

RESUMO

Hydroxy-3-methylglutaryl-CoA synthase 1 (HMGCS1) is a key enzyme in the mevalonate pathway of cholesterol synthesis. Dysregulation of HMGCS1 expression is a common occurrence in many solid tumors. It was also found to be overexpressed in newly diagnosed (ND) and relapsed/refractory (RR) acute myeloid leukemia (AML) patients. Previous study proved that HMGCS1 could induce drug-resistance in AML cells. However, the underlying mechanism how HMGCS1 contributed to chemoresistance remains elusive. Here, we confirmed that HMGCS1 inhibitor Hymeglusin enhanced cytarabine/Adriamycin (Ara-c/ADR) chemo-sensitivity in AML cells lines. Moreover, Ara-c-resistant HL-60 cells (HL-60/Ara-c) and ADR-resistant HL-60 cells (HL-60/ADR) were more sensitive to HMGCS1 inhibition than HL-60 cells. In addition, we demonstrated that the transcription factor GATA1 was the upstream regulator of HMGCS1 and could directly bind to the HMGCS1 promoter. After treatment of Tunicamycin (Tm), the number of mitochondria was increased and the damage of endoplasmic reticulum (ER) was reduced in bone marrow cells from AML-RR patients, compared to cells from AML-CR group. HMGCS1 protected mitochondria and ER under ER stress and up-regulated unfold protein response (UPR) downstream molecules in AML cells. In summary, we proved that HMGCS1 could upregulate UPR downstream components, protect mitochondria and ER from damage in AML cells under stress, therefore conferring drug resistance. Therefore, HMGCS1 could serve as a novel target for treatment of patients with intolerant chemotherapy and AML-RR patients.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Retículo Endoplasmático/efeitos dos fármacos , Hidroximetilglutaril-CoA Sintase/genética , Leucemia Mieloide Aguda/genética , Mitocôndrias/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Células da Medula Óssea/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fator de Transcrição GATA1/genética , Células HL-60 , Humanos , Hidroximetilglutaril-CoA Sintase/antagonistas & inibidores , Tunicamicina/farmacologia
18.
Nat Metab ; 3(2): 196-210, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33619377

RESUMO

Ketone bodies are generated in the liver and allow for the maintenance of systemic caloric and energy homeostasis during fasting and caloric restriction. It has previously been demonstrated that neonatal ketogenesis is activated independently of starvation. However, the role of ketogenesis during the perinatal period remains unclear. Here, we show that neonatal ketogenesis plays a protective role in mitochondrial function. We generated a mouse model of insufficient ketogenesis by disrupting the rate-limiting hydroxymethylglutaryl-CoA synthase 2 enzyme gene (Hmgcs2). Hmgcs2 knockout (KO) neonates develop microvesicular steatosis within a few days of birth. Electron microscopic analysis and metabolite profiling indicate a restricted energy production capacity and accumulation of acetyl-CoA in Hmgcs2 KO mice. Furthermore, acetylome analysis of Hmgcs2 KO cells revealed enhanced acetylation of mitochondrial proteins. These findings suggest that neonatal ketogenesis protects the energy-producing capacity of mitochondria by preventing the hyperacetylation of mitochondrial proteins.


Assuntos
Metabolismo Energético/fisiologia , Corpos Cetônicos/biossíntese , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Ácido 3-Hidroxibutírico/metabolismo , Acetilação , Animais , Animais Recém-Nascidos , Hidroximetilglutaril-CoA Sintase/genética , Hidroximetilglutaril-CoA Sintase/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Knockout , Microvasos/fisiologia , Consumo de Oxigênio
19.
Sci Rep ; 11(1): 1082, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441887

RESUMO

Sandalwood (Santalum album L.) is famous for its unique fragrance derived from the essential oil of heartwood, whose major components are santalols. To understand the mechanism underlying the biosynthesis of santalols, in this study, we cloned two related genes involved in the mevalonate pathway in S. album coding for acetyl-CoA C-acetyl transferase (AACT) and 3-hydroxy-3-methyglutary-CoA synthase (HMGS). These genes were characterized and functionally analyzed, and their expression profiles were also assessed. An AACT gene designated as SaAACT (GenBank accession No. MH018694) and a HMGS gene designated as SaHMGS (GenBank accession No. MH018695) were successfully cloned from S. album. The deduced SaAACT and SaHMGS proteins contain 415 and 470 amino acids, and the corresponding size of their open-reading frames is 1538 bp and 1807 bp, respectively. Phylogenetic trees showed that the SaAACT protein had the closest relationship with AACT from Hevea brasiliensis and the SaHMGS proteins had the highest homology with HMGS from Siraitia grosvenorii. Functional complementation of SaAACT and SaHMGS in a mutant yeast strain deficient in these proteins confirmed that SaAACT and SaHMGS cDNA encodes functional SaAACT and SaHMGS that mediate mevalonate biosynthesis in yeast. Tissue-specific expression analysis revealed that both genes were constitutively expressed in all examined tissues (roots, sapwood, heartwood, young leaves, mature leaves and shoots) of S. album, both genes showing highest expression in roots. After S. album seedlings were treated with 100 µM methyl jasmonate, the expression levels of SaAACT and SaHMGS genes increased, suggesting that these genes were responsive to this elicitor. These studies provide insight that would allow further analysis of the role of genes related to the sandalwood mevalonate pathway in the regulation of biosynthesis of sandalwood terpenoids and a deeper understanding of the molecular mechanism of santalol biosynthesis.


Assuntos
Acetil-CoA C-Acetiltransferase/genética , Hidroximetilglutaril-CoA Sintase/genética , Proteínas de Plantas/genética , Santalum/genética , Acetil-CoA C-Acetiltransferase/metabolismo , Clonagem Molecular , Hidroximetilglutaril-CoA Sintase/metabolismo , Proteínas de Plantas/metabolismo , Santalum/metabolismo
20.
Med Sci Sports Exerc ; 53(1): 47-57, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32826638

RESUMO

PURPOSE: This study aimed to determine the effect of exercise training on preventing lipotoxic cardiomyopathy and to investigate the role of the 3-hydroxy-3-methylglutaryl-CoA synthase 2 (HMGCS2) and miR-344g-5p in cardiomyocytes. METHODS: Male C57BL/6 mice were fed a 60% high-fat diet (HFD) for 12 wk then began swimming exercise or remained sedentary for 8 wk. Thereafter, cardiac function was assessed by echocardiography, and heart tissue and plasma were collected for further measurements. The molecular mechanism of exercise was investigated after treating Hmgcs2 siRNA in palmitate-induced neonatal mouse cardiomyocytes. RESULTS: HFD induced myocardial hypertrophy and fibrosis and reduced coronary reserve and cardiac function. HMGCS2 levels increased, but junctophilin-2 (JPH2) levels decreased in HFD mice hearts. Such effects were attenuated by swimming exercise. Mechanistically, Hmgcs2 silencing prevented apoptosis and caspase-3 cleavage and elevated the expression of JPH2 in palmitate-stimulated cardiomyocytes. In addition, exercise promoted miR-344g-5p expression in HFD hearts. The overexpression of miR-344g-5p by chemical mimic reduced HMGCS2, apoptosis, and caspase-3 cleavage and elevated JPH2 expression in palmitate-induced cardiomyocytes. CONCLUSION: Our results suggest that exercise limits lipid metabolic disorder, cardiac hypertrophy, and fibrosis and aids in the prevention of lipotoxic cardiomyopathy. Exercise-mediated cardioprotection by upregulating miR-344g-5p, which targets Hmgcs2 mRNA, prohibits HMGCS2 upregulation and thus lipotoxicity.


Assuntos
Cardiomiopatias/metabolismo , Cardiomiopatias/prevenção & controle , Dieta Hiperlipídica/efeitos adversos , Hidroximetilglutaril-CoA Sintase/metabolismo , MicroRNAs/metabolismo , Miócitos Cardíacos/metabolismo , Condicionamento Físico Animal , Animais , Peso Corporal , Cálcio/metabolismo , Cardiomegalia/prevenção & controle , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/patologia , Modelos Animais de Doenças , Ecocardiografia Doppler , Fibrose/prevenção & controle , Cetonas/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Proteínas Musculares/metabolismo , Natação/fisiologia , Regulação para Cima
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