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1.
Hepatobiliary Surg Nutr ; 13(3): 393-411, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38911213

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-38801936

ABSTRACT

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.


Subject(s)
Basic-Leucine Zipper Transcription Factors , Cell Differentiation , MicroRNAs , Rho Guanine Nucleotide Exchange Factors , Humans , MicroRNAs/genetics , MicroRNAs/metabolism , Cell Differentiation/drug effects , Basic-Leucine Zipper Transcription Factors/genetics , Basic-Leucine Zipper Transcription Factors/metabolism , K562 Cells , Rho Guanine Nucleotide Exchange Factors/genetics , Rho Guanine Nucleotide Exchange Factors/metabolism , Erythroid Cells/drug effects , Erythroid Cells/metabolism , Proto-Oncogene Proteins c-jun/metabolism , Proto-Oncogene Proteins c-jun/genetics , Methyltransferases/genetics , Methyltransferases/metabolism
3.
Environ Sci Pollut Res Int ; 31(21): 30779-30792, 2024 May.
Article in English | MEDLINE | ID: mdl-38613763

ABSTRACT

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.


Subject(s)
8-Hydroxy-2'-Deoxyguanosine , Endocrine Disruptors , Humans , Adult , China , Cross-Sectional Studies , Female , 8-Hydroxy-2'-Deoxyguanosine/urine , Male , Middle Aged , Phenols , Benzhydryl Compounds , Environmental Exposure , Phthalic Acids , Glomerular Filtration Rate/drug effects , East Asian People
4.
J Pharmacol Sci ; 154(4): 316-325, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38485350

ABSTRACT

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.


Subject(s)
Diabetes Mellitus, Experimental , Diabetic Nephropathies , Flavonoids , MicroRNAs , Animals , Diabetic Nephropathies/drug therapy , Diabetic Nephropathies/genetics , Diabetic Nephropathies/metabolism , Diabetes Mellitus, Experimental/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Fibrosis
5.
Environ Res ; 251(Pt 2): 118708, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38493858

ABSTRACT

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.


Subject(s)
Lead , Risk Assessment/methods , Humans , Lead/toxicity , Blood-Brain Barrier/drug effects , Neurotoxicity Syndromes/etiology , Dose-Response Relationship, Drug
6.
Pharm Biol ; 62(1): 33-41, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38100532

ABSTRACT

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.


Subject(s)
Antineoplastic Agents , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Antineoplastic Agents/pharmacology , Apoptosis , Carcinoma, Non-Small-Cell Lung/drug therapy , Cell Line, Tumor , Drug Resistance, Neoplasm , Gefitinib/pharmacology , Interleukin-22 , Lung Neoplasms/genetics , Proto-Oncogene Proteins c-akt/metabolism , Quinazolines/pharmacology , STAT3 Transcription Factor/metabolism , Antineoplastic Agents, Phytogenic/pharmacology
8.
Am J Physiol Gastrointest Liver Physiol ; 325(3): G213-G229, 2023 09 01.
Article in English | MEDLINE | ID: mdl-37366545

ABSTRACT

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.


Subject(s)
Bile Duct Neoplasms , Cholangiocarcinoma , MicroRNAs , Rats , Animals , Transcription Factor AP-1/genetics , Endocannabinoids , Lipoprotein Lipase , Glycerol , Lipopolysaccharides , Cholangiocarcinoma/pathology , MicroRNAs/genetics , MicroRNAs/metabolism , Bile Ducts, Intrahepatic/metabolism , Bile Ducts, Intrahepatic/pathology , Bile Duct Neoplasms/metabolism , Carcinogenesis , Cell Line, Tumor
9.
J Cancer Res Clin Oncol ; 149(7): 3895-3903, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36008690

ABSTRACT

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.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/metabolism , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Retrospective Studies , Protein Kinase Inhibitors/adverse effects , Mutation , ErbB Receptors
11.
Chemosphere ; 308(Pt 2): 136394, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36099984

ABSTRACT

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.


Subject(s)
Cosmetics , Environmental Pollutants , Phthalic Acids , Triclosan , 8-Hydroxy-2'-Deoxyguanosine , Adult , Bayes Theorem , Benzophenones/toxicity , Benzophenones/urine , Environmental Exposure/analysis , Environmental Pollutants/urine , Esters/toxicity , Female , Humans , Oxidative Stress , Parabens/analysis , Phthalic Acids/metabolism , Triclosan/toxicity
12.
Mol Nutr Food Res ; 65(15): e2100157, 2021 08.
Article in English | MEDLINE | ID: mdl-34061446

ABSTRACT

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.


Subject(s)
Betaine/pharmacology , Intracellular Signaling Peptides and Proteins/antagonists & inhibitors , Mechanistic Target of Rapamycin Complex 1/metabolism , Methyltransferases/antagonists & inhibitors , Muscle, Skeletal/drug effects , Muscle, Skeletal/physiopathology , S-Adenosylmethionine/metabolism , Aging/drug effects , Aging/pathology , Animals , Gene Expression Regulation/drug effects , Intracellular Membranes/drug effects , Intracellular Membranes/metabolism , Lysosomes/drug effects , Lysosomes/metabolism , Male , Methionine/metabolism , Mice, Inbred C57BL , Muscle, Skeletal/metabolism , Protein Biosynthesis/drug effects , Signal Transduction/drug effects
13.
Sci Rep ; 6: 25124, 2016 04 26.
Article in English | MEDLINE | ID: mdl-27112969

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-26974319

ABSTRACT

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.


Subject(s)
Folic Acid/pharmacology , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Inflammation/pathology , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , Cell Hypoxia/drug effects , Cell Line , Cytokines/genetics , Cytokines/metabolism , Cytoprotection/drug effects , Folic Acid/toxicity , Gene Expression Regulation/drug effects , Humans , Inflammation/metabolism , Inflammation Mediators/metabolism , Models, Biological , Phosphorylation/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , Real-Time Polymerase Chain Reaction , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism
15.
Sci Rep ; 5: 13046, 2015 Aug 12.
Article in English | MEDLINE | ID: mdl-26267249

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-25553117

ABSTRACT

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.


Subject(s)
Antineoplastic Agents/pharmacology , Cell Proliferation/drug effects , Cyclooxygenase 2/metabolism , NF-kappa B/antagonists & inhibitors , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/physiology , Sesquiterpenes/pharmacology , Blotting, Western , Carcinoma , Cell Line, Tumor , Gene Expression Profiling , Humans , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms/pathology , Real-Time Polymerase Chain Reaction , Signal Transduction
17.
Opt Express ; 22(16): 19589-94, 2014 Aug 11.
Article in English | MEDLINE | ID: mdl-25321042

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-24150295

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-24036901

ABSTRACT

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.


Subject(s)
Hypertension/complications , Inflammation/pathology , Smoking/adverse effects , Adult , Aged , Alcohol Drinking , Asian People , Biomarkers/metabolism , C-Reactive Protein/metabolism , Chemokine CCL2/metabolism , China , Female , Flow Cytometry , Humans , Hypertension/physiopathology , Interleukin-1beta/metabolism , Interleukin-6/metabolism , Logistic Models , Male , Middle Aged , Tumor Necrosis Factor-alpha/metabolism , Vascular Cell Adhesion Molecule-1/metabolism
20.
Asia Pac J Clin Nutr ; 20(4): 624-31, 2011.
Article in English | MEDLINE | ID: mdl-22094849

ABSTRACT

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.


Subject(s)
Adolescent Behavior , Feeding Behavior , Transients and Migrants/statistics & numerical data , Adolescent , Child , China/epidemiology , Cross-Sectional Studies , Female , Humans , Male , Social Class , Surveys and Questionnaires
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