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PURPOSE: We analyzed the effectiveness, safety, and mid-term oncological outcomes of short-course radiotherapy (SCRT) and oxaliplatin-based consolidation chemotherapy in patients with locally advanced rectal cancer (LARC). METHODS: We retrospectively evaluated 64 patients with LARC who underwent SCRT and tegafox (tegafur-uracil/leucovorin plus oxaliplatin) or mFOLFOX-6 (5-fluorouracil, leucovorin, and oxaliplatin) consolidation chemotherapy before surgery between January 2015 and December 2020. Tumor response, patient compliance, toxicity, surgical outcomes, overall survival (OS), and disease-free survival (DFS) were analyzed. RESULTS: Sixty-four patients with a mean age of 58.67 years (44 males) were included; 48 (75%) had tumors within 5 cm of the anal verge. Additionally, 93.8% of the patients underwent at least 2 months of chemotherapy, and three required dose reduction. Grade III toxicity occurred in 2 patients, and 10 had a clinical complete response and opted for non-operative management. One patient experienced tumor progression and underwent further treatment without surgery. Among the 53 patients who underwent surgery, 51 (96.2%) had sphincter preservation, 3 had Clavien-Dindo grade III complications, and no mortality occurred. The complete response rate for the entire cohort was 23.4%. Moreover, 47 patients (74.6%) had a neoadjuvant rectal score of < 16 after treatment. After a median follow-up time of 32.01 months, 6 (9.3%) had local recurrence, and 17 (26.6%) had distant metastasis. The 3-year OS, DFS and stoma-free rates were 89.5%, 65.5%, and 78.1% respectively. CONCLUSION: SCRT followed by oxaliplatin-based consolidation chemotherapy is safe and effective for tumor downstaging in LARC, further improving the sphincter preservation rate.
Assuntos
Neoplasias Retais , Masculino , Humanos , Pessoa de Meia-Idade , Oxaliplatina , Neoplasias Retais/tratamento farmacológico , Leucovorina/uso terapêutico , Quimioterapia de Consolidação , Estudos Retrospectivos , Preservação de Órgãos , Fluoruracila/uso terapêutico , Terapia Neoadjuvante/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimiorradioterapia , Resultado do Tratamento , Estadiamento de NeoplasiasRESUMO
Studies have reported positive short-term and histopathological results of transanal total mesorectal excision (TaTME) for mid-low rectal cancer. The long-term oncological outcomes are diverse, and concerns regarding the high local recurrence (LR) rate of TaTME have recently increased. We retrospectively analyzed 298 consecutive patients who underwent Laparoscopic TME (LapTME) or TaTME between January 2015 and December 2019. Propensity score-matching (PSM) was performed with patients matched for demographics and stage. After PSM, 63 patients were included in each group. The TaTME group had a longer mean operative time (394 vs. 333 min, p < 0.001). The blood loss, diverting stoma rate, and conversion rate were similar. Postoperatively, TaTME and LapTME had compatible complications, recovery, and hospital stay. A similar specimen quality was detected in both groups. After a mean follow-up period of 41−47 months, TaTME had less LR than LapTME (9.5% vs. 23.8%, p = 0.031). The 3-year overall survival was 80.3% in the TaTME group and 73.6% in the LapTME group (p = 0.331). The 3-year disease-free survival (DFS) rate was 72.0% in the TaTME group and 56.6% in the LapTME group (p = 0.038). In conclusion, better DFS and fewer LR events were observed after TaTME; thus, TaTME can be considered a safe and feasible approach in patients with low rectal cancer.
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Neoadjuvant short course radiotherapy (SCRT) followed by consolidation chemotherapy (CCT) is an alternative treatment for locally advanced rectal cancer (LARC). We performed this systematic review and meta-analysis to explore the tumor response and oncological outcomes of this new approach compared to conventional chemoradiotherapy (CRT). An online search of the PubMed, Embase, and Cochrane Library databases was performed. This review included 7507 patients from 14 different cohorts. The pCR rate was higher with SCRT + CCT than that with CRT (RR: 1.60; 95% CI: 1.35−1.91; p < 0.01). SCRT + CCT provided a higher ypN0 response (RR: 1.06; 95% CI: 1.01−1.12; p = 0.02). There were no differences in R0 resection and positive CRM rates; however, more sphincter-preservation surgeries were performed in the SCRT + CCT arm (RR: 1.06; 95% CI: 1.01−1.11; p = 0.02). There was no difference in the OS and DFS between the SCRT + CCT and the CRT arms (OS: HR: 0.85, p = 0.07; DFS: HR: 0.88, p = 0.08). The compliance and toxicity were comparable between the SCRT and CRT groups. In the subgroup analysis, patients who underwent four or more cycles of CCT had better pCR and DFS events. Therefore, SCRT followed by consolidation chemotherapy might be an effective alternative treatment for LARC.
Assuntos
Segunda Neoplasia Primária , Neoplasias Retais , Quimiorradioterapia , Quimioterapia de Consolidação , Humanos , Terapia Neoadjuvante , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/cirurgiaRESUMO
This study aimed to explore the safety and efficacy of neoadjuvant SCRT and tegafur−uracil/leucovorin plus oxaliplatin (TEGAFOX) for LARC in comparison to those of the modified 5-fluorouracil, leucovorin, and oxaliplatin (mFOLFOX-6) regimen. We retrospectively evaluated 15 and 22 patients with LARC who underwent SCRT, followed by consolidation chemotherapy with TEGAFOX and mFOLFOX-6 before surgery, respectively, between January 2015 and December 2019. The primary endpoint was the tumor response rate. The secondary endpoints were compliance, toxicity, complications, overall survival (OS), and disease-free survival (DFS). The dose reduction rate was lower in the TEGAFOX group (0 vs. 9.1% (n = 2)). No grade III-IV toxicities occurred in the TEGAFOX group. Two and four patients in the TEGAFOX and mFOLFOX-6 groups, respectively, achieved clinical complete responses. The pathologic complete response rate was lower in the TEGAFOX group (7.7% vs. 17.6%). Overall, 11 (73.3%) and 17 (81.0%) patients had a neoadjuvant rectal (NAR) score of <16 in the TEGAFOX and mFOLFOX-6 groups, respectively. All patients in this study received sphincter-preservation surgery. One patient in each group developed Clavien−Dindo grade III complications. There were no significant between-group differences in the 3-year OS (81.8% vs. 84.8%, p = 0.884) and 3-year DFS (72% vs. 71.6%, p = 0.824) rates. TEGAFOX, as consolidation chemotherapy after SCRT, achieves good tumor downstaging and patient compliance in LARC. The toxicity, complications, and surgical outcomes are similar to those of mFOLFOX-6. Thus, TEGAFOX can be considered a chemotherapy option for rectal cancer treatment.
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ABSTRACT: The impact of immune cells (ICs) expressing various markers remains poorly understood in nonmetastatic colorectal cancer patients who have undergone colectomy. Here, we aimed to clarify the correlation between IC density and clinical parameters and survival.Programmed death protein-1 (PD-1), programmed cell death protein ligand-1 (PD-L1), clusters of differentiation (CD)-3, CD-8, and CD45RO immunostaining was performed for 421 patients using tissue microarray and automatic counting. Tumor stroma area immune density was assessed in comparison to clinical histological factors and surgical outcomes.High-density CD-8 expression was significantly associated with current smoking habits or a smoking history (Pâ=â.006). High-density of PD-1 expression was correlated with Lynch syndrome patients (Pâ<â.001) and with patients who did not consume alcohol (Pâ=â.034). A significant decrease in CR45RO expression density was associated with aging (Pâ=â.002 and râ=â-0.014), and high-density CD-3, CD-8, and PD-1 expression was significantly associated with right colon tumor location (Pâ<â.001). High CD-3 and PD-L1 expression was significantly associated with early tumor T-staging (Pâ=â.018 and Pâ=â.002). High-density PD-1 expression was significantly correlated with mucinous type adenocarcinoma (Pâ=â.027) and poor differentiation (Pâ<â.001). For treatment outcomes, multivariate analysis confirmed that patients exhibiting high-density PD-L1 expression possessed significantly longer disease free survival (adjusted hazard ratio: 0.752, 95% confidence interval [CI]: 0.61-0.92, Pâ=â.006) and overall survival (adjusted hazard ratio: 0.872, 95% CI: 0.75-1.91, Pâ=â.064)Significantly varied density in IC subsets was related to distinct demographic or clinic-histological factors. The presence of high-density PD-L1-expressing ICs is an independent favorable prognostic factor for disease free survival and overall survival among stage I to III colorectal cancer patients.
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Antígeno B7-H1/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Receptor de Morte Celular Programada 1/metabolismo , Adulto , Idoso , Antígenos CD/metabolismo , Biomarcadores Tumorais/metabolismo , Intervalo Livre de Doença , Feminino , Humanos , Ligantes , Linfócitos do Interstício Tumoral , Masculino , Pessoa de Meia-Idade , Prognóstico , Receptor de Morte Celular Programada 1/imunologiaRESUMO
BACKGROUND: Approximately 20% of patients with colorectal cancer are initially diagnosed with stage IV disease. This study aims to examine the role of regional lymph node (LN) status in metastatic colorectal cancer (mCRC) with respect to clinicopathologic features and survival outcomes. METHODS: We investigated 1147 patients diagnosed with mCRC and had undergone surgical resection of the primary CRC. A total of 167 patients were placed in the LN-negative (LN-) group and another 980 in the LN-positive (LN+) group. RESULTS: LN+ patients exhibited a significantly higher rate of T4 tumors (p = 0.008), poorly differentiated adenocarcinoma (p < 0.001), lymphovascular invasion (p < 0.001), and perineural invasion (p < 0.001) than those in the LN- group. LN- patients had a significantly higher rate of lung metastasis (p < 0.001), whereas the rate of peritoneal seeding (p < 0.001) and systemic node metastasis (p < 0.001) was both significantly higher in the LN+ group. The 5-year overall survival (OS) in the LN+ group was significantly poorer than that in the LN- group (LN- vs. LN+ 23.2% vs. 18.1%; p = 0.040). In patients with curative resection, the 5-year OS rate has no significant difference between the two groups (LN- vs. LN+ 19.5% vs. 24.3%; p = 0.890). CONCLUSIONS: Metastatic CRC patients with LN+ who underwent primary tumor resection may present with more high-risk pathological features, more peritoneal seeding, and systemic node metastasis, but less lung metastasis than LN- patients. LN+ patients had poorer long-term outcomes compared with that in LN- patients. Nevertheless, with curative resection, LN+ patients could have similar survival outcomes as LN- patients.
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Neoplasias Colorretais , Excisão de Linfonodo , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Humanos , Linfonodos/patologia , Linfonodos/cirurgia , Metástase Linfática , Estadiamento de Neoplasias , Prognóstico , Estudos RetrospectivosRESUMO
Toona sinensis is a common edible vegetable that is used in certain Chinese dishes and has importance in folk medicine. The leaf extracts of T sinensis possess and exhibit anticancer efficacy against various cancer cell types. In Taiwanese folklore, Antrodia camphorata, also known as "Niu-Cheng-Zi," is used in traditional medicine to treat various illnesses. Its fruit and mycelium possess various potent antiproliferative properties. Two studies from our group have reported that T sinensis or A camphorata has the ability to cause apoptosis in various cancer cells. Conversely, underlying molecular mechanisms and any beneficial effects remain unknown. This study shows anticancer efficacy for both T sinensis and A camphorata co-treatments that target HL-60 cells. The combination index values indicate that 40 µg/mL of T sinensis and 25 µg/mL of A camphorata as a combined treatment shows a synergetic effect, which reduces HL-60 cell proliferation. Alternately, this treatment exhibited no cytotoxic effects for human umbilical vein endothelial cells. Western blot data showed that T sinensis and A camphorata as a combined treatment result in augmented expression of apoptosis, cytochrome c release, Bcl-2 inhibition, expression of Bax, Fas, and FasL, as well as the cleavage of Bid in HL-60 cells. Moreover, this combined treatment overshadowed monotherapy in its ability to inhibit uPAR, MMP-9, MMP-2, COX-2 expression, and PGE2 secretions. Our study strongly implies that this combined treatment offers more beneficial effects to suppress and treat leukemia due to apoptosis-mediated cell inhibition. Further in vivo studies related to the combined treatment could establish its future potential.
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Antrodia , Medicamentos de Ervas Chinesas , Leucemia , Apoptose , Células Endoteliais , Humanos , Polyporales , ToonaRESUMO
Canine respiratory diseases are commonly seen in dogs along with co-infections with multiple respiratory pathogens, including viruses and bacteria. Virus infections in even vaccinated dogs were also reported. The clinical signs caused by different respiratory etiological agents are similar, which makes differential diagnosis imperative. An oligonucleotide microarray system was developed in this study. The wild type and vaccine strains of canine distemper virus (CDV), influenza virus, canine herpesvirus (CHV), Bordetella bronchiseptica and Mycoplasma cynos were detected and differentiated simultaneously on a microarray chip. The detection limit is 10, 10, 100, 50 and 50 copy numbers for CDV, influenza virus, CHV, B. bronchiseptica and M. cynos, respectively. The clinical test results of nasal swab samples showed that the microarray had remarkably better efficacy than the multiplex PCR-agarose gel method. The positive detection rate of microarray and agarose gel was 59.0% (n=33) and 41.1% (n=23) among the 56 samples, respectively. CDV vaccine strain and pathogen co-infections were further demonstrated by the microarray but not by the multiplex PCR-agarose gel. The oligonucleotide microarray provides a highly efficient diagnosis alternative that could be applied to clinical usage, greatly assisting in disease therapy and control.
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Infecções Bacterianas/veterinária , Doenças do Cão/diagnóstico , Análise em Microsséries/métodos , Técnicas de Diagnóstico Molecular/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Infecções Respiratórias/veterinária , Viroses/veterinária , Animais , Infecções Bacterianas/diagnóstico , Cães , Infecções Respiratórias/diagnóstico , Viroses/diagnósticoRESUMO
Cellular accumulation of mono(2-ethylhexyl)phthalate (MEHP) has been recently demonstrated to disturb fat cell energy metabolism; however, the underlying mechanism remained unclear. The study aimed to determine how MEHP influenced fat cell transcriptome and how the changes might contribute to bioenergetics. Because of the pivotal role of PPARγ in energy metabolism of fat cells, comparative microarray analysis of gene expression in 3T3-L1 adipocytes treated with both MEHP and rosiglitazone was performed. Pathway enrichment analysis and gene ontology (GO) enrichment analysis revealed that both treatments caused up-regulation of genes involved in PPAR signaling/energy metabolism-related pathways and down-regulation of genes related to adipokine/inflammation signals. MEHP/rosiglitazone-treated adipocytes exhibited increased levels of lipolysis, glucose uptake, and glycolysis; the gene expression profiles provided molecular basis for the functional changes. Moreover, MEHP was shown to induce nuclear translocation and activation of PPARγ. The similarity in gene expression and functional changes in response to MEHP and rosiglitazone suggested that MEHP influenced bioenergetics and adipokine network mainly via PPARγ. Importantly, adipokine levels in C57BL/6J mice with di(2-ethylhexyl)phthalate (DEHP) treatments provided in vivo evidence for microarray results. On the basis of correlation between gene expression and functional assays, possible involvements of genes in bioenergetics of MEHP-treated adipocytes were proposed.
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Adipócitos/efeitos dos fármacos , Adipocinas/metabolismo , Dietilexilftalato/análogos & derivados , Células 3T3-L1 , Adipócitos/metabolismo , Adipocinas/genética , Animais , Dietilexilftalato/farmacologia , Metabolismo Energético/efeitos dos fármacos , Ácidos Graxos/metabolismo , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica/métodos , Glucose/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Análise em Microsséries , PPAR gama/genética , PPAR gama/metabolismo , Rosiglitazona , Tiazolidinedionas/farmacologiaRESUMO
Di(2-ethylhexyl) phthalate (DEHP) is the most crucial phthalate derivative added to polyvinyl chloride as a plasticizer. This study examined the effects of low-dose exposure to DEHP during adolescence on sperm function in adult rats. The male rats were daily gavaged with 30, 100, 300, and 1000 µg kg(-1) of DEHP or corn oil from postnatal day (PND) 42 until PND 105. The selection of DEHP doses ranged from the mean daily intake by the normal-population exposure levels to no-observed-adverse-effect level of DEHP for the endpoints evaluated until adulthood. Significant increases in the percentage of sperm with tail abnormality, tendency for sperm DNA fragmentation index (DFI) and percentage of sperm with DFI were found in those exposed to 100, 300, and 1000 µg kg(-1) (P < 0.05). We observed a significant increase of hydrogen peroxide (H2 O2 ) generation in the sperm of the 1000 µg kg(-1) group compared with the control group (P < 0.05). The excessive production of sperm H2 O2 coincided with an increase in sperm DFI. In this study, the lowest-observed-adverse-effect level for sperm toxicity was considered to be 100 µg DEHP/kg/day in sperm morphology and chromatin DNA damage. Further research is necessary to clarify the mechanisms of DEHP-related sperm ROS generation on sperm DNA damage. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 706-712, 2016.
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Dietilexilftalato/toxicidade , Poluentes Ambientais/toxicidade , Plastificantes/toxicidade , Espermatozoides/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Masculino , Nível de Efeito Adverso não Observado , Ratos/crescimento & desenvolvimento , Ratos Sprague-DawleyRESUMO
Phthalates are lipophilic and tend to accumulate in adipose tissue, an important regulator of energy balance and glucose homeostasis. The study aimed to determine whether cellular phthalate accumulation influenced fat cell energy metabolism. Following a 3-day treatment with adipogenesis-inducing medium and a 2-day treatment with adipogenesis-maintaining medium, 3T3-L1 cells differentiated into adipocytes in the presence of a phthalate at a clinically relevant concentration (30-300 µM) for another 6 days. Two phthalates, di(2-ethylhexyl)phthalate and di-n-butylphthalate, and their metabolites, mono(2-ethylhexyl)phthalate (MEHP) and mono-n-butylphthalate, were used here. The phthalate treatments caused no marked effect on cytotoxicity and adipogenesis. Only the MEHP-treated adipocytes were found having smaller lipid droplets; MEHP accumulated in cells in a dose- and time-dependent manner. The MEHP-treated adipocytes exhibited significant increases in lipolysis and glucose uptake; quantitative real-time polymerase chain reaction (qPCR) analysis revealed correlated changes in expression of marker genes involved in adipogenesis, lipid metabolism, and glucose uptake. Analysis of oxygen consumption rate (a mitochondrial respiration indicator) and extracellular acidification rate (a glycolysis indicator) indicated a higher energy metabolism in the adipocytes. qPCR analysis of critical genes involved in mitochondrial biogenesis and/or energy metabolism showed that expression of peroxisome proliferator-activated receptor γ coactivator-1α, sirtuin 3, and protein kinase A were significantly enhanced in the MEHP-treated adipocytes. In vitro evidence of MEHP impacts on lipolysis, glucose uptake/glycolysis, and mitochondrial respiration/biogenesis demonstrates that MEHP accumulation disturbs energy metabolism of fat cells.
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Adipócitos/metabolismo , Dietilexilftalato/análogos & derivados , Metabolismo Energético/efeitos dos fármacos , Células 3T3-L1/efeitos dos fármacos , Células 3T3-L1/metabolismo , Adipócitos/efeitos dos fármacos , Animais , Dietilexilftalato/farmacocinética , Dietilexilftalato/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Gotículas Lipídicas/efeitos dos fármacos , Gotículas Lipídicas/metabolismo , Lipólise/efeitos dos fármacos , CamundongosRESUMO
Antrodia camphorata is a well-known medicinal mushroom in Taiwan. The broth from a fermented culture of Antrodia camphorata (AC) has been shown to induce apoptosis in cultured human premyelocytic leukemia (HL-60) cells. In the present study, we examined the effects of AC on cell cycle arrest in vitro in HL-60 cells and on tumor regression in vivo using an athymic nude mouse model. We found that AC (20-80 µg mL(-1)) treatment significantly induced G1 cell-cycle arrest in HL-60 cells by reducing the levels of cyclin D1, CDK4, cyclin E, CDK2, cyclin A, and phosphorylation of retinoblastoma protein (p-Rb). Moreover, AC treatment led to significantly increased protein expression levels of CDK inhibitors, including p21(WAF1) and p15(NIK4B). Additionally, AC treatment markedly induced intracellular ROS generation and mitochondrial dysfunction in HL-60 cells. Furthermore, the in vivo study results revealed that AC treatment was effective in terms of delaying the tumor incidence in nude mice that had been inoculated with HL-60 cells as well as in reducing the tumor burden. Histological analysis confirmed that AC treatment significantly modulated the xenografted tumor progression as demonstrated by a reduction in mitotic cells. Our data strongly suggest that Antrodia camphorata could be an anti-cancer agent for human leukemia.
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Antrodia/química , Proliferação de Células/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Leucemia/tratamento farmacológico , Leucemia/fisiopatologia , Extratos Vegetais/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Ciclina D/genética , Ciclina D/metabolismo , Ciclina E/genética , Ciclina E/metabolismo , Quinase 4 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação para Baixo/efeitos dos fármacos , Células HL-60 , Humanos , Leucemia/genética , Leucemia/metabolismo , Camundongos , Camundongos NusRESUMO
Toona sinensis is one of the most popular vegetarian cuisines in Taiwan and it has been shown to induce apoptosis in cultured human premyelocytic leukemia (HL-60) cells. In the present study, we examined the effects of T. sinensis leaf extracts (TS extracts) on tumor regression using in vitro cell culture and an in vivo athymic nude mice model. We found that TS extracts (10-75 µg/mL) arrested HL-60 cells at the G1-S transition phase through the reductions of Cyclin D1, CDK4, Cyclin E, CDK2, and Cyclin A, and induction of CDK inhibitor p27KIP levels. Furthermore, VEGF expression and release was significantly inhibited by TS extracts. Notably, TS extracts treatment was effective in terms of delaying tumor incidence in the nude mice inoculated with HL-60 cells as well as reducing the tumor burden. Histological analysis confirmed that TS extracts significantly modulated tumor progression in xenograft tumor. Furthermore, a similar pattern of results were observed from gallic acid (5 and 10 µg/mL), a major compound in TS, caused G1 arrest through regulations of cell-cycle regulatory proteins. Our data suggest that T. sinensis exerts antiproliferative effects on HL-60 cells in vitro and in vivo due mainly to the presence of gallic acid.
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Ácido Gálico/farmacologia , Meliaceae/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Animais , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Feminino , Ácido Gálico/química , Células HL-60 , Humanos , Masculino , Camundongos , Camundongos Nus , Neoplasias Experimentais/tratamento farmacológico , Extratos Vegetais/química , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
A recombinant Huh7-PPRE-Luc cell line for analyzing the peroxisome proliferator response element (PPRE)-driven luciferase activity was established. The cells exhibited a good dose-response induction in PPRE-driven luciferase activity by three subtypes of peroxisome proliferator-activated receptor (PPAR) agonists as well as by a retinoid X receptor agonist, 9-cis-retinoic acid. Among five environmental chemicals tested, benzyl butyl phthalate and bisphenol induced PPRE-driven luciferase activation in Huh7-PPRE-Luc cells and caused adipogenic differentiation of 3T3-L1 cells. This recombinant Huh7-PPRE-Luc cell line would be useful for screening potential environmental obesogens with PPAR activity.
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Bioensaio/métodos , Poluentes Ambientais/análise , Luciferases/biossíntese , Proliferadores de Peroxissomos/metabolismo , Elementos de Resposta , Adipogenia , Diferenciação Celular , Linhagem Celular , Relação Dose-Resposta a Droga , Hepatócitos/metabolismo , HumanosRESUMO
Dioxin exposure has been positively associated with human type II diabetes. Because lipophilic dioxins accumulate mainly in adipose tissue, this study aimed to determine if dioxins induce metabolic dysfunction in fat cells. Using 3T3-L1 cells as an in vitro model, we analyzed the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a model dioxin, on adipogenic differentiation, glucose uptake, and lipolysis. TCDD inhibited adipogenic differentiation, as determined by using oil droplet formation and adipogenic marker gene expression, including PPARgamma (peroxisome proliferator-activated receptor gamma), C/EBPalpha (CCAAT/enhancer-binding protein alpha), and Glut4 (glucose transporter type 4). Effects of TCDD on glucose uptake were evaluated using fully differentiated 3T3-L1 adipocytes, revealing that TCDD significantly attenuated insulin-induced glucose uptake dose dependently. Inhibition of aryl hydrocarbon receptor (AhR) by alpha-naphthoflavone (alpha-NF), an AhR inhibitor, did not prevent the inhibitory effect of TCDD on glucose uptake, suggesting that TCDD attenuates insulin-induced glucose uptake in an AhR-independent manner. Effects of TCDD on lipolysis were determined using glycerol release assay. We found that TCDD had no marked effect on isoproterenol-induced glycerol release in fully differentiated 3T3-L1 adipocytes. These results provide in vitro evidence of TCDD's effects on fat cell metabolism, suggesting dioxin exposure in development of insulin resistance and type II diabetes.
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Adipócitos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Glucose/metabolismo , Insulina/farmacologia , Dibenzodioxinas Policloradas/toxicidade , Células 3T3-L1 , Adipócitos/citologia , Animais , Sequência de Bases , Primers do DNA , Isoproterenol/farmacologia , Camundongos , Receptores de Hidrocarboneto Arílico/metabolismoRESUMO
To investigate the possible involvement of betel-quid chewing in adipocyte dysfunction, we determined the effects of arecoline, a major alkaloid in areca nuts, on adipogenic differentiation (adipogenesis), lipolysis, and glucose uptake by fat cells. Using mouse 3T3-L1 preadipocytes, we showed that arecoline inhibited adipogenesis as determined by oil droplet formation and adipogenic marker gene expression. The effects of arecoline on lipolysis of differentiated 3T3-L1 adipocytes were determined by the glycerol release assay, indicating that arecoline induced lipolysis in an adenylyl cyclase-dependent manner. The diabetogenic effects of arecoline on differentiated 3T3-L1 adipocytes were evaluated by the glucose uptake assay, revealing that > or = 300 microM arecoline significantly attenuated insulin-induced glucose uptake; however, no marked effect on basal glucose uptake was detected. Moreover, using 94 subjects that were randomly selected from a health check-up, we determined the association of betel-quid chewing with hyperlipidemia and its related risk factors. Hyperlipidemia frequency and serum triglyceride levels of betel-quid chewers were significantly higher than those of non-betel-quid chewers. In this study, we demonstrated that arecoline inhibits adipogenic differentiation, induces adenylyl cyclase-dependent lipolysis, and interferes with insulin-induced glucose uptake. Arecoline-induced fat cell dysfunction may lead to hyperlipidemia and hyperglycemia/insulin-resistance. These findings provide the first in vitro evidence of betel-quid chewing modulation of adipose cell metabolism that could contribute to the explanation of the association of this habit with metabolic syndrome disorders.