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1.
Hepatobiliary Surg Nutr ; 13(3): 393-411, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38911213

RESUMEN

Background: Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-associated death. Emerging evidence suggests that autophagy plays a critical role in HCC tumorigenesis, metastasis, and prognosis. Choline is an essential nutrient related to prolonged survival and reduced risk of HCC. However, it remains unclear whether this phenomenon is mediated by autophagy. Methods: Two HCC cell lines (HUH-7 and Hep3B) were used in the present study. Cell growth was evaluated by cell counting kit 8 (CCK-8), colony formation, and in vivo mouse xenografts assays. Cell motility was calculated by wound healing and transwell assays. Autophagosomes were measured by transmission electron microscope (TEM), and autophagy flux was detected by mRFP-GFP-labeled LC3 protein. The mRNA level of genes was measured by quantitative real-time polymerase chain reaction (qRT-PCR). The protein levels were detected by Western blotting (WB). Results: We found that choline inhibited the proliferation, migration, and invasion of HCC cells by downregulating autophagy in vitro and in vivo. Upregulated expression of the solute carrier family 5 member 7 (SLC5A7), a specific choline transporter, correlated with better HCC prognosis. We further discovered that choline could promote SLC5A7 expression, upregulate cytoplasm p53 expression to impair the AMPK/mTOR pathway, and attenuate autophagy. Finally, we found that choline acted synergistically with sorafenib to attenuate HCC development in vitro and in vivo. Conclusions: Our findings provide novel insights into choline-mediated autophagy in HCC, providing the foothold for its future application in HCC treatment.

2.
Toxicology ; 505: 153843, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38801936

RESUMEN

Benzene, a widely used industrial chemical, has been clarified to cause hematotoxicity. Our previous study suggested that miR-451a may play a role in benzene-induced impairment of erythroid differentiation. However, the mechanism underlying remains unclear. In this study, we explored the role of miR-451a and its underlying mechanisms in hydroquinone (HQ)-induced suppression of erythroid differentiation in K562 cells. 0, 1.0, 2.5, 5.0, 10.0, and 50 µM HQ treatment of K562 cells resulted in a dose-dependent inhibition of erythroid differentiation, as well as the expression of miR-451a. Bioinformatics analysis was conducted to predict potential target genes of miR-451a and dual-luciferase reporter assays confirmed that miR-451a can directly bind to the 3'-UTR regions of BATF, SETD5, and ARHGEF3 mRNAs. We further demonstrated that over-expression or down-regulation of miR-451a altered the expression of BATF, SETD5, and ARHGEF3, and also modified erythroid differentiation. In addition, BATF, SETD5, and ARHGEF3 were verified to play a role in HQ-induced inhibition of erythroid differentiation in this study. Knockdown of SETD5 and ARHGEF3 reversed HQ-induced suppression of erythroid differentiation while knockdown of BATF had the opposite effect. On the other hand, we also identified c-Jun as a potential transcriptional regulator of miR-451a. Forced expression of c-Jun increased miR-451a expression and reversed the inhibition of erythroid differentiation induced by HQ, whereas knockdown of c-Jun had the opposite effect. And the binding site of c-Jun and miR-451a was verified by dual-luciferase reporter assay. Collectively, our findings indicate that miR-451a and its downstream targets BATF, SETD5, and ARHGEF3 are involved in HQ-induced erythroid differentiation disorder, and c-Jun regulates miR-451a as a transcriptional regulator in this process.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico , Diferenciación Celular , MicroARNs , Factores de Intercambio de Guanina Nucleótido Rho , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Diferenciación Celular/efectos de los fármacos , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Células K562 , Factores de Intercambio de Guanina Nucleótido Rho/genética , Factores de Intercambio de Guanina Nucleótido Rho/metabolismo , Células Eritroides/efectos de los fármacos , Células Eritroides/metabolismo , Proteínas Proto-Oncogénicas c-jun/metabolismo , Proteínas Proto-Oncogénicas c-jun/genética , Metiltransferasas/genética , Metiltransferasas/metabolismo
3.
Environ Sci Pollut Res Int ; 31(21): 30779-30792, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38613763

RESUMEN

Individual typical endocrine-disrupting chemicals (EDCs), including organophosphate triesters (OPEs), parabens, triclosan (TCS), bisphenols, benzophenones (BPs), phthalates (PAEs), and synthetic phenolic antioxidants (SPAs), are associated with renal dysfunction. However, the combined effects and underlying mechanisms of mixed EDC exposure on renal function remain unclear. Two hundred ninety-nine adult participants were enrolled in the cross-sectional survey conducted in Guangzhou, China. Urinary levels of 7 OPEs, 6 parabens, TCS, 14 bisphenols, 8 BPs, 15 PAEs, 4 SPAs, and 8-hydroxy-2'-deoxyguanosine (8-OHdG) were determined, and estimated glomerular filtration rate (eGFR) was served as the outcome index. We found elevated levels of diphenyl phosphate (DPP), bisphenol A (BPA), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-butyl phthalate (MBP) showed dose-responsive associations with eGFR decline, However, nonlinear associations were observed for bis(2-butoxyethyl) hydrogen phosphate (BBOEP), TCS, 4-hydroxybenzophenone (HBP), mono-n-pentyl phthalate (MnPP), and mono-benzyl phthalate (MBzP). The quantile-based g-computation model demonstrated that a quartile increase in the EDC mixture corresponded to a 0.383-SD decrease (95% CI - 0.658 ~ - 0.108, P = 0.007) in eGFR. Notably, BPA was identified as the primary contributor to this effect. Moreover, 8-OHdG mediated the eGFR decline associated with EDC mixtures with a mediation proportion of 25.49%. A sex-modified effect was also observed (P = 0.004), indicating that exposure to the mixture of EDC was linked to more pronounced renal dysfunction in females. Our novel findings suggest that exposure to a typical mixture of EDCs is associated with renal dysfunction in the general adult population of Southern China. Furthermore, 8-OHdG may play a role in the pathogenesis of EDC mixture-related renal dysfunction.


Asunto(s)
8-Hidroxi-2'-Desoxicoguanosina , Disruptores Endocrinos , Humanos , Adulto , China , Estudios Transversales , Femenino , 8-Hidroxi-2'-Desoxicoguanosina/orina , Masculino , Persona de Mediana Edad , Fenoles , Compuestos de Bencidrilo , Exposición a Riesgos Ambientales , Ácidos Ftálicos , Tasa de Filtración Glomerular/efectos de los fármacos , Pueblos del Este de Asia
4.
Environ Res ; 251(Pt 2): 118708, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38493858

RESUMEN

The mode of action (MOA) framework is proposed to inform a biological link between chemical exposures and adverse health effects. Despite a significant increase in knowledge and awareness, the application of MOA in human health risk assessment (RA) remains limited. This study aims to discuss the adoption of MOA for health RA within a regulatory context, taking our previously proposed but not yet validated MOA for lead neurotoxicity as an example. We first conducted a quantitative weight of evidence (qWOE) assessment, which revealed that the MOA has a moderate confidence. Then, targeted bioassays were performed within an in vitro blood-brain barrier (BBB) model to quantitatively validate the scientific validity of key events (KEs) in terms of essentiality and concordance of empirical support (dose/temporal concordance), which increases confidence in utilizing the MOA for RA. Building upon the quantitative validation data, we further conducted benchmark dose (BMD) analysis to map dose-response relationships for the critical toxicity pathways, and the lower limit of BMD at a 5% response (BMDL5) was identified as the point of departure (POD) value for adverse health effects. Notably, perturbation of the Aryl Hydrocarbon Receptor (AHR) signaling pathway exhibited the lowest POD value, measured at 0.0062 µM. Considering bioavailability, we further calculated a provisional health-based guidance value (HBGV) for children's lead intake, determining it to be 2.56 µg/day. Finally, the health risk associated with the HBGV was assessed using the hazard quotient (HQ) approach, which indicated that the HBGV established in this study is a relative safe reference value for lead intake. In summary, our study described the procedure for utilizing MOA in health RA and set an example for MOA-based human health risk regulation.


Asunto(s)
Plomo , Medición de Riesgo/métodos , Humanos , Plomo/toxicidad , Barrera Hematoencefálica/efectos de los fármacos , Síndromes de Neurotoxicidad/etiología , Relación Dosis-Respuesta a Droga
5.
J Pharmacol Sci ; 154(4): 316-325, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38485350

RESUMEN

Diabetic nephropathy is a common complication of diabetes, accumulating evidence underscores the pivotal role of tubulointerstitial fibrosis in the progression of diabetic nephropathy. However, the underlying mechanisms remain incompletely understood. Although the mechanisms in diabetic nephropathy fibrosis have been the focus of many studies, only limited information is currently available concerning microRNA regulation in tubulointerstitial fibrosis. In this study, we aimed to investigate the roles of miR-320a-3p and bone morphogenetic protein-6 (BMP6) in tubulointerstitial fibrosis. After inducing fibrosis with high glucose in HK-2 cells, we found that miR-320a-3p is significantly up-regulated, whereas BMP6 is markedly down-regulated. These changes suggest close link between miR-320a-3p and BMP6 in tubulointerstitial fibrosis. To elucidate this phenomenon, miR-320a-3p mimic, inhibitor and siBMP6 were employed. We observed in miR-320a-3p mimic group the fibrosis marker include alpha smooth muscle actin and type I collagen was significantly up-regulated, whereas BMP6 exhibited the opposite trend. Additionally, we found icariin could alleviate tubulointerstitial fibrosis by downregulation the miR-320a-3p expression. In conclusion, miR-320a-3p promotes tubulointerstitial fibrosis during the development of DN by suppressing BMP signal pathway activity via inhibiting BMP6 expression. Suggesting that miR-320a-3p represents a potential therapeutic target for tubulointerstitial fibrosis induced by diabetic nephropathy.


Asunto(s)
Diabetes Mellitus Experimental , Nefropatías Diabéticas , Flavonoides , MicroARNs , Animales , Nefropatías Diabéticas/tratamiento farmacológico , Nefropatías Diabéticas/genética , Nefropatías Diabéticas/metabolismo , Diabetes Mellitus Experimental/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Fibrosis
6.
Pharm Biol ; 62(1): 33-41, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38100532

RESUMEN

CONTEXT: Non-small cell lung cancer (NSCLC) is the most common type of lung cancer. Gefitinib is a first-line treatment for NSCLC. However, its effectiveness is hindered by the development of drug resistance. At present, Shenqi Fuzheng injection (SFI) is widely accepted as an adjuvant therapy in NSCLC. OBJECTIVE: This study investigates the molecular mechanism of SFI when combined with gefitinib in regulating cell progression among EGFR-TKI-resistant NSCLC. MATERIALS AND METHODS: We established gefitinib-resistant PC9-GR cells by exposing gefitinib escalation from 10 nM with the indicated concentrations of SFI in PC9 cells (1, 4, and 8 mg/mL). Quantitative real-time polymerase chain reaction was performed to assess gene expression. PC9/GR and H1975 cells were treated with 50 ng/mL of interleukin (IL)-22 alone or in combination with 10 mg/mL of SFI. STAT3, p-STAT3, AKT, and p-AKT expression were evaluated using Western blot. The effects on cell proliferation, clonogenicity, and apoptosis in NSCLC cells were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), colony formation and flow cytometry assays. RESULTS: SFI treatment alleviated the development of gefitinib resistance in NSCLC. PC9/GR and H1975 cells treated with SFI significantly exhibited a reduction in IL-22 protein and mRNA overexpression levels. SFI effectively counteracted the activation of the STAT3/AKT signaling pathway induced by adding exogenous IL-22 to PC9/GR and H1975 cells. Moreover, IL-22 combined with gefitinib markedly increased cell viability while reducing apoptosis. In contrast, combining SFI with gefitinib and the concurrent treatment of SFI with gefitinib and IL-22 demonstrated the opposite effect. DISCUSSION AND CONCLUSION: SFI can be a valuable therapeutic option to address gefitinib resistance in NSCLC by suppressing the IL-22/STAT3/AKT pathway.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Antineoplásicos/farmacología , Apoptosis , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Línea Celular Tumoral , Resistencia a Antineoplásicos , Gefitinib/farmacología , Interleucina-22 , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Quinazolinas/farmacología , Factor de Transcripción STAT3/metabolismo , Antineoplásicos Fitogénicos/farmacología
8.
Am J Physiol Gastrointest Liver Physiol ; 325(3): G213-G229, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37366545

RESUMEN

The endocannabinoid system (ECS) is dysregulated in various liver diseases. Previously, we had shown that the major endocannabinoid 2-arachidonoyl glycerol (2-AG) promoted tumorigenesis of intrahepatic cholangiocarcinoma (ICC). However, biosynthesis regulation and clinical significance of 2-AG remain elusive. In the present study, we quantified 2-AG by gas chromatography/mass spectrometry (GC/MS) and showed that 2-AG was enriched in patients with ICC samples as well as in thioacetamide-induced orthotopic rat ICC model. Moreover, we found that diacylglycerol lipase ß (DAGLß) was the principal synthesizing enzyme of 2-AG that significantly upregulated in ICC. DAGLß promoted tumorigenesis and metastasis of ICC in vitro and in vivo and positively correlated with clinical stage and poor survival in patients with ICC. Functional studies showed that activator protein-1 (AP-1; heterodimers of c-Jun and FRA1) directly bound to the promoter and regulated transcription of DAGLß, which can be enhanced by lipopolysaccharide (LPS). miR-4516 was identified as the tumor-suppressing miRNA of ICC that can be significantly suppressed by LPS, 2-AG, or ectopic DAGLß overexpression. FRA1 and STAT3 were targets of miR-4516 and overexpression of miRNA-4516 significantly suppressed expression of FRA1, SATA3, and DAGLß. Expression of miRNA-4516 was negatively correlated with FRA1, SATA3, and DAGLß in patients with ICC samples. Our findings identify DAGLß as the principal synthesizing enzyme of 2-AG in ICC. DAGLß promotes oncogenesis and metastasis of ICC and is transcriptionally regulated by a novel AP-1/DAGLß/miR4516 feedforward circuitry.NEW & NOTEWORTHY Dysregulated endocannabinoid system (ECS) had been confirmed in various liver diseases. However, regulation and function of 2-arachidonoyl glycerol (2-AG) and diacylglycerol lipase ß (DAGLß) in intrahepatic cholangiocarcinoma (ICC) remain to be elucidated. Here, we demonstrated that 2-AG was enriched in ICC, and DAGLß was the principal synthesizing enzyme of 2-AG in ICC. DAGLß promotes tumorigenesis and metastasis in ICC via a novel activator protein-1 (AP-1)/DAGLß/miR4516 feedforward circuitry.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , MicroARNs , Ratas , Animales , Factor de Transcripción AP-1/genética , Endocannabinoides , Lipoproteína Lipasa , Glicerol , Lipopolisacáridos , Colangiocarcinoma/patología , MicroARNs/genética , MicroARNs/metabolismo , Conductos Biliares Intrahepáticos/metabolismo , Conductos Biliares Intrahepáticos/patología , Neoplasias de los Conductos Biliares/metabolismo , Carcinogénesis , Línea Celular Tumoral
9.
J Cancer Res Clin Oncol ; 149(7): 3895-3903, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36008690

RESUMEN

PURPOSE: The aim of this retrospective study is to evaluate the impact on efficacy and safety between epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) alone and in combination with Shenqi Fuzheng injection (SFI) in patients with advanced NSCLC harboring epidermal growth factor receptor (EGFR) activating mutations. METHODS: Retrospectively, information of 88 patients receiving EGFR-TKIs as first-line targeted treatment or in combination with SFI in the Affiliated Drum Tower Hospital of Nanjing University Medical College and the Affiliated Cancer Hospital of Anhui University of Science and Technology was collected. The primary endpoint was to assess progression-free survival (PFS) and safety of EGFR-TKIs alone or in combination with SFI. RESULTS: Between January 2016 and December 2019, a total of 88 patients were enrolled in this research, including 50 cases in the EGFR-TKIs single agent therapy group and 38 cases in the SFI combined with EGFR-TKIs targeted-therapy group. The median PFS (mPFS) of monotherapy group was 10.50 months (95%CI 9.81-11.19), and 14.30 months (95%CI 10.22-18.38) in the combination therapy group. Compared to the single EGFR-TKIs administration, combinational regimen with SFI exhibited a lower incidence of rash and diarrhea in patients and was even better tolerated. CONCLUSIONS: SFI combined with the first-generation EGFR-TKIs are more efficient, can prominently prolong the PFS and attenuate the adverse reactions in patients with advanced NSCLC with EGFR-sensitive mutations.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Estudios Retrospectivos , Inhibidores de Proteínas Quinasas/efectos adversos , Mutación , Receptores ErbB
11.
Chemosphere ; 308(Pt 2): 136394, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36099984

RESUMEN

Humans are constantly exposed to parabens (PBs), triclosan (TCS), benzophenones (BPs), and phthalate esters (PAEs) due to the widespread existence of these chemicals in personal care products (PCPs), and the high frequency of usage for humans. Previous studies indicated each class of the above-mentioned chemicals can exhibit potential adverse effects on humans, in particular DNA oxidative damage. However, the health risk assessment of combined exposures to multiple PCPs is limited, especially the overall dose-effect of mixtures of these chemicals on DNA oxidative damage. In this study, we measured the urinary levels of 6 PBs, TCS, 8 BPs, 15 metabolites of PAEs (mono-PAEs), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) from 299 adults simultaneously. PBs, TCS, BPs, and mono-PAEs were frequently detected in urinary samples with median concentrations of 52.888, 0.737, 1.305, and 141.381 ng/ml, suggesting a broad, low-level exposure among participants. Risk assessments indicated approximately 22% and 15% of participants suffered health risks (Hazard index >1) from exposure to TCS and PAEs. The relationship between 8-OHdG levels and chemical exposure was estimated by Bayesian kernel machine regression (BKMR) models. It indicated an overall positive correlation between the mixture of these chemicals and 8-OHdG, with methylparaben and mono-benzyl phthalate contributing the most to this association. Of note, sex-related differences were observed, in which exposure to PCPs led to higher health risks and more pronounced dose-effect on DNA damage in the female population. Our novel findings reveal the health risks of exposure to low-level PCPs mixtures and further point out the overall dose-response relationship between DNA oxidative damage and PCP mixtures.


Asunto(s)
Cosméticos , Contaminantes Ambientales , Ácidos Ftálicos , Triclosán , 8-Hidroxi-2'-Desoxicoguanosina , Adulto , Teorema de Bayes , Benzofenonas/toxicidad , Benzofenonas/orina , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/orina , Ésteres/toxicidad , Femenino , Humanos , Estrés Oxidativo , Parabenos/análisis , Ácidos Ftálicos/metabolismo , Triclosán/toxicidad
12.
Mol Nutr Food Res ; 65(15): e2100157, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34061446

RESUMEN

SCOPE: The muscle loss during aging results from the blunt of protein synthesis and poses threat to the elderly health. This study aims to investigate whether betaine affects muscle loss by improving protein synthesis. METHODS AND RESULTS: Male C57BL/6J mice are raised from age 12 or 15 months. Mice are fed with AIN-93M diet without or with 2% w/v betaine in distilled water as control group or betaine intervention group (Bet), respectively. Betaine supplementation to mice demonstrates better body composition, grip strength, and motor function. Muscle morphology upregulates expression of myogenic regulate factors, and elevates myosin heavy chain and also improves in Bet group. Betaine promotes muscle protein synthesis via tethering mammalian target of rapamycin complex1 protein kinase (mTORC1) on the lysosomal membrane thereby activating mTORC1 signaling. All these effects aforementioned are time-dependent (p < 0.05). Ultrahigh-performance liquid chromatography results show that betaine increases S-adenosyl-l-methionine (SAM) via methionine cycle. SAM sensor-Samtor-overexpression in C2C12 cells could displace mTORC1 from lysosome thereby inhibiting the mTORC1 signaling. Addition of betaine attenuates this inhibition by increasing SAM level and then disrupting interaction of Samtor complex. CONCLUSIONS: These observations indicate that betaine could promisingly promote protein synthesis to delay age-related muscle loss.


Asunto(s)
Betaína/farmacología , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Metiltransferasas/antagonistas & inhibidores , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/fisiopatología , S-Adenosilmetionina/metabolismo , Envejecimiento/efectos de los fármacos , Envejecimiento/patología , Animales , Regulación de la Expresión Génica/efectos de los fármacos , Membranas Intracelulares/efectos de los fármacos , Membranas Intracelulares/metabolismo , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Masculino , Metionina/metabolismo , Ratones Endogámicos C57BL , Músculo Esquelético/metabolismo , Biosíntesis de Proteínas/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
13.
Sci Rep ; 6: 25124, 2016 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-27112969

RESUMEN

Two AlGaN samples with different strain were designed to investigate mechanism of stress-driven composition evolution. It is discovered that AlGaN grown on AlN or (AlN/GaN superlattices (SLs))/GaN both consist of two distinct regions with different compositions: transition region and uniform region, which is attributed to the compositional pulling effect. The formation of the transition region is due to the partial stress release caused by the generation of misfit dislocations near the hetero-interface. And the Al composition in the uniform region depends on the magnitude of residual strain. The difference in relaxation degree is 80.5% for the AlGaN epilayers grown on different underlayers, leading to a large Al composition difference of 22%. The evolutionary process of Al composition along [0001] direction was investigated in detail.

14.
PLoS One ; 11(3): e0151553, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26974319

RESUMEN

Though hypoxia has been implicated as a cause of inflammation, the underlying mechanism is not well understood. Folic acid has been shown to provide protection against oxidative stress and inflammation in patients with cardiovascular disease and various models approximating insult to tissue via inflammation. It has been reported that hypoxia-induced inflammation is associated with oxidative stress, upregulation of hypoxia-inducible factor 1-alpha (HIF-1α), and production of pro-inflammatory molecules. Whether folic acid protects human monocytic cells (THP-1 cells) against hypoxia-induced damage, however, remains unknown. We used THP-1 cells to establish a hypoxia-induced cellular injury model. Pretreating THP-1 cells with folic acid attenuated hypoxia-induced inflammatory responses, including a decrease in protein and mRNA levels of interleukin (IL)-1ß and tumor necrosis factor-alpha (TNF-α), coupled with increased levels of IL-10. Folic acid also reduced hypoxia-induced Akt phosphorylation and decreased nuclear accumulation of HIF-1α protein. Both LY294002 (a selective inhibitor of phosphatidyl inositol-3 kinase, PI3K) and KC7F2 (a HIF-1α inhibitor) reduced levels of hypoxia-induced inflammatory cytokines. We also found that insulin (an Akt activator) and dimethyloxallyl glycine (DMOG, a HIF-1α activator) induced over-expression of inflammatory cytokines, which could be blocked by folic acid. Taken together, these findings demonstrate how folic acid attenuates the hypoxia-induced inflammatory responses of THP-1 cells through inhibition of the PI3K/Akt/HIF-1α pathway.


Asunto(s)
Ácido Fólico/farmacología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Inflamación/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Hipoxia de la Célula/efectos de los fármacos , Línea Celular , Citocinas/genética , Citocinas/metabolismo , Citoprotección/efectos de los fármacos , Ácido Fólico/toxicidad , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Inflamación/metabolismo , Mediadores de Inflamación/metabolismo , Modelos Biológicos , Fosforilación/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
15.
Sci Rep ; 5: 13046, 2015 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-26267249

RESUMEN

Free exciton (FX) and bound exciton (BX) in Al0.5Ga0.5N/Al0.35Ga0.65N multiple quantum wells (MQWs) with different Si-doping levels in the well layers are investigated by photoluminescence (PL) spectra. Low temperature (10 K) PL spectra identify a large binding energy of 87.4 meV for the BX in undoped sample, and 63.6 meV for the BX in Si-doped (2 × 10(18 ) cm(-3)) sample. They are attributed to O-bound and Si-bound excitons, respectively. The large binding energies of BX are assumed to originate from the strong quantum confinement in the quantum wells, which also leads to a stronger FX PL peak intensity in comparison with BX at 10 K. Si-doping is found to suppress the FX quenching by reducing threading dislocation density (TDD) in the well layers, leading to a significant improvement of IQE from 33.7% to 45%.

16.
Theranostics ; 5(3): 302-21, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25553117

RESUMEN

Cancer stem cells play a central role in the pathogenesis of nasopharyngeal carcinoma and contribute to both disease initiation and relapse. In this study, cyclooxygenase-2 (COX-2) was found to regulate cancer stem-like side population cells of nasopharyngeal carcinoma cells and enhance cancer stem-like cells' characteristics such as higher colony formation efficiency and overexpression of stemness-associated genes. The regulatory effect of COX-2 on cancer stem-like characteristics may be mediated by ABCG2. COX-2 overexpression by a gain-of-function experiment increased the proportion of side population cells and their cancer stemness properties. The present study also demonstrated that in contrast to the classical chemotherapy drug 5-fluorouracil, which increased the proportion of side population cells and upregulated the expression of COX-2, parthenolide, a naturally occurring small molecule, preferentially targeted the side population cells of nasopharyngeal carcinoma cells and downregulated COX-2. Moreover, we found that the cancer stem-like cells' phenotype was suppressed by using COX-2 inhibitors NS-398 and CAY10404 or knocking down COX-2 with siRNA and shRNA. These findings suggest that COX-2 inhibition is the mechanism by which parthenolide induces cell death in the cancer stem-like cells of nasopharyngeal carcinoma. In addition, parthenolide exhibited an inhibitory effect on nuclear factor-kappa B (NF-κB) nucler translocation by suppressing both the phosphorylation of IκB kinase complex and IκBα degradation. Taken together, these results suggest that parthenolide may exert its cancer stem cell-targeted chemotherapy through the NF-κB/COX-2 pathway.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , FN-kappa B/antagonistas & inhibidores , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/fisiología , Sesquiterpenos/farmacología , Western Blotting , Carcinoma , Línea Celular Tumoral , Perfilación de la Expresión Génica , Humanos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patología , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción de Señal
17.
Opt Express ; 22(16): 19589-94, 2014 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-25321042

RESUMEN

The injection current dependence of optical polarization of ultraviolet (UV) light-emitting diodes (LEDs) emitting at wavelength of 310 nm and 277 nm was investigated by electroluminescence (EL) measurements. For both diodes, it was found that the degree of polarization (DOP) decreased obviously as the injection current increased. We attribute the decrease in DOP to the different changing trend of the intensity of the light emission from transverse electric (TE) polarization (E⊥c) and transverse magnetic (TM) polarization (E∥c) as the injected carriers occupy higher states above k = 0 with increasing the injection current. For the 277 nm LED, even the polarization switching from TE to TM mode was observed.

18.
Opt Express ; 21(21): 24497-503, 2013 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-24150295

RESUMEN

The exciton localization in wurtzite AlxGa1-xN alloys with x varying from 0.41 to 0.63 has been studied by deep-ultraviolet photoluminescence (PL) spectroscopy and picosecond time-resolved PL spectroscopy. Obvious S-shape temperature dependence was observed indicating that the strong exciton localization can be formed in high Al composition AlxGa1-xN alloys. It was also found that the Al composition dependence of exciton localization energy of AlGaN alloys is inconsistent with that of the excitonic linewidth. We contribute the inconsistency to the strong zero-dimensional exciton localization.

19.
J Hypertens ; 31(9): 1798-805, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24036901

RESUMEN

OBJECTIVES: Previous studies indicated that cigarette smokers were more likely to develop hypertension, and both smoking and hypertension were associated with inflammation. Whether inflammation mediates the relationship of them is unclear. This study aims to examine whether inflammation mediates the association between smoking and hypertension. METHODS: Nine hundred and eighty-four Chinese current smokers from a community-based chronic diseases survey in Guangzhou and Zhuhai were interviewed about sociodemographics, smoking, chronic conditions, and other health-related variables. Hypertension was defined according to 2007 European Society of Hypertension and European Society of Cardiology (ESH-ESC) Practice Guidelines. Inflammatory markers including C-reactive protein (CRP), interleukin (IL)-6, IL-1ß, monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-α (TNF-α), and vascular cell adhesion molecule-1 (VCAM-1) were measured by flow cytometry. Logistic regressions were performed to assess the mediation of inflammation on the relationship between smoking quantity and hypertension. RESULTS: We observed a positive association between smoking quantity and hypertension (P<0.05). After controlling for potential confounders, daily cigarette consumption was significantly associated with higher level of CRP and VCAM-1 and lower level of TNF-α among six measured inflammatory markers, and the current smokers with hypertension had significantly higher level of MCP-1 and CRP than those smokers who were normotensive. Furthermore, the association between smoking quantity and hypertension was mediated by CRP, which accounted for 58.59% of the estimated causal effect of smoking on hypertension. CONCLUSION: We have confirmed previous observations that smoking quantity was positively associated with hypertension, and the results of our study suggested that the association between smoking and hypertension was probably mediated by CRP.


Asunto(s)
Hipertensión/complicaciones , Inflamación/patología , Fumar/efectos adversos , Adulto , Anciano , Consumo de Bebidas Alcohólicas , Pueblo Asiatico , Biomarcadores/metabolismo , Proteína C-Reactiva/metabolismo , Quimiocina CCL2/metabolismo , China , Femenino , Citometría de Flujo , Humanos , Hipertensión/fisiopatología , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Modelos Logísticos , Masculino , Persona de Mediana Edad , Factor de Necrosis Tumoral alfa/metabolismo , Molécula 1 de Adhesión Celular Vascular/metabolismo
20.
Asia Pac J Clin Nutr ; 20(4): 624-31, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22094849

RESUMEN

BACKGROUND: It is estimated that the number of migrant adolescents in Chinese cities may have reached 25 million. However, little research has been conducted on their dietary habits. The objective of this study was to compare dietary habits between migrant and local adolescents in Shenzhen, China. METHODS: A school based cross-sectional study was conducted in 3368 adolescents (aged 11-18 years; 52.5% boys). A self-administered questionnaire completed by adolescents was designed to gather information on socio-demographic characteristics, meal location, food pattern and intake. RESULTS: Of the 3368 adolescents, 58.2% were migrants. Compared with locals, migrant adolescents showed significantly higher percentage of having three meals away-from home. Nearly half of the subjects (45.6 %) skipped breakfast, with a higher proportion among migrant students (48.5 vs 41.5%). Migrant students consumed street food more frequently (12.2 vs 8.5%), while the difference was opposite in Western fast food intake (27.3 vs 32.5%). No significant difference was found in snacks intake between these two groups. Migrant students exhibited lower percentage of vegetables (57.3 vs 63.7%), fruits (27.7 vs 38.3%), meats (37.0 vs 44.3%), soybean (11.6 vs 17.5%) and dairy products (28.4 vs 42.5%) intake daily. After adjusted for socio-demographic confounders, the difference mentioned above still remained except Western fast food. CONCLUSION: Dietary habits among adolescents showed pronounced household variation. Migrant adolescents are more likely to exhibit unhealthy dietary behavior. Schools and families should collaborate to improve the dietary environment for adolescents, especially those from migrant families.


Asunto(s)
Conducta del Adolescente , Conducta Alimentaria , Migrantes/estadística & datos numéricos , Adolescente , Niño , China/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Clase Social , Encuestas y Cuestionarios
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