ABSTRACT
Three new flavonoid glycosides, (S)-4',6,8-trihydroxyflavanone-7-C-glucoside (1), (R)-4',6,8- trihydroxyflavanone-7-C-glucoside (2) and distenin-7-O-ß-D-glucoside (3), along with nine known flavonoids (4-12) were isolated from the aerial of Pteridium acquilinum. Their structures were elucidated by the analysis of spectroscopy data and their comparison with the reported values. The two C-glycosyl flavanones (1 and 2), were isolated from this specie, which might be chemotaxonomic markers of this specie. In addition, three new flavonoids were preliminarily examined for their anti-inflammatory activity. Compounds 1-3 inhibited the NF-κB induction by 46.3%, 59.6% and 29.2%, respectively.
ABSTRACT
During the COVID-19 lockdown in the Beijing-Tianjin-Hebei (BTH) region in China, large decrease in nitrogen oxides (NOx) emissions, especially in the transportation sector, could not avoid the occurrence of heavy PM2.5 pollution where nitrate dominated the PM2.5 mass increase. To experimentally reveal the effect of NOx control on the formation of PM2.5 secondary components (nitrate in particular), photochemical simulation experiments of mixed volatile organic compounds (VOCs) under various NOx concentrations with smog chamber were performed. The proportions of gaseous precursors in the control experiment were comparable to ambient conditions typically observed in the BTH region. Under relatively constant VOCs concentrations, when the initial NOx concentration was reduced to 40% of that in the control experiment (labelled as NOx,0), the particle mass concentration was not significantly reduced, but when the initial NOx concentration decreased to 20 % of NOx,0, the mass concentration of particles as well as nitrate and organics showed a sudden decrease. A "critical point" where the mass concentration of secondary aerosol started to decline as the initial NOx concentration decreased, located at 0.2-0.4 NOx,0 (or 0.18-0.44 NO2,0) in smog chamber experiments. The oxidation capacity and solar radiation intensity played key roles in the mass concentration and compositions of the formed particles. In field observations in the BTH region in the autumn and winter seasons, the "critical point" exist at 0.15-0.34 NO2,0, which coincided mostly with the laboratory simulation results. Our results suggest that a reduction of NOx emission by >60% could lead to significant reductions of secondary aerosol formation, which can be an effective way to further alleviate PM2.5 pollution in the BTH region.
ABSTRACT
Medulloblastoma (MB) is a malignant tumor of the cerebellum that occurs in children and infants. Abnormal neuronal differentiation can lead to brain tumors, and topoisomerase IIß (Top IIß) plays an important role in neuronal differentiation. The aim of this study was to investigate the molecular mechanism of 13-cis retinoic acid (13-cis RA) promoting the expression of Top IIß and inducing neuronal differentiation in human MB Daoy cells. The results showed that 13-cis RA inhibited the cell proliferation and induced cell cycle arrest in G0/G1 phase. The cells differentiated into a neuronal phenotype, with high expression of the neuronal marker microtubule-associated protein 2 (MAP2) and abundant Top IIß, and obvious neurite growth. Chromatin immunoprecipitation (ChIP) assay showed that histone H3 lysine 27 tri-methylation (H3K27me3) modification in Top IIß promoter decreased after 13-cis RA-induced cell differentiation, while jumonji domain-containing protein 3 (JMJD3) binding in Top IIß promoter increased. These results suggest that H3K27me3 and JMJD3 can regulate the expression of Top IIß gene, which is related to inducing neural differentiation. Our results provide new insights into understanding the regulatory mechanisms of Top IIß during neuronal differentiation and imply the potential application of 13-cis RA in the clinical treatment of MB.
Subject(s)
Cerebellar Neoplasms , Medulloblastoma , Child , Humans , Histones/genetics , Histones/metabolism , Isotretinoin/metabolism , Medulloblastoma/genetics , Medulloblastoma/pathology , Epigenesis, Genetic , DNA Topoisomerases, Type II/genetics , DNA Topoisomerases, Type II/metabolism , Cell Differentiation , Cerebellar Neoplasms/genetics , Cerebellar Neoplasms/pathology , Tretinoin/pharmacology , Tretinoin/metabolismABSTRACT
Magnesium matrix composites are considered a desired solution for lightweight applications. As an attractive thermal management material, diamond particle-reinforced Mg matrix (Mg/diamond) composites generally exhibit thermal conductivities lower than expected. To exploit the potential of heat conduction, a combination of Cr coating on diamond particles and squeeze casting was used to prepare Mg/diamond (Cr) composites. The thickness of the Cr coating under different coating processes (950 °C/30 min, 950 °C/60 min, 950 °C/90 min, 1000 °C/30 min, and 1050 °C/30 min) was measured by FIB-SEM to be 1.09-2.95 µm. The thermal conductivity (TC) of the Mg/diamond composites firstly increased and then decreased, while the coefficient of thermal expansion (CTE) of Mg/diamond (Cr) composite firstly decreased and then increased with the increase in Cr coating thickness. The composite exhibited the maximum TC of 202.42 W/(m·K) with a 1.20 µm Cr coating layer, while a minimum CTE of 5.82 × 10-6/K was recorded with a coating thickness of 2.50 µm. The results clearly manifest the effect of Cr layer thickness on the TC and CTE of Mg/diamond composites.
ABSTRACT
Extensive investigations have revealed that iso-suillin, a secondary metabolite isolated from Suillus flavus, could induce cell cycle arrest and apoptosis in human chronic myeloid leukemia K562 cells, human hepatocellular carcinoma SMMC-7721 cell line, and human small cell lung cancer H446 cell line in vitro. In the present study, human lung cancer A549 cells were used to reveal the mechanism of iso-suillin's effects on lung adenocarcinoma, which were detected both in vitro and in vivo. Results showed that iso-suillin potently inhibited A549 cell proliferation through an early G1 arrest. Iso-suillin also induced A549 cell apoptosis in vitro. Phosphorylation of p53 at serines 15 and 20 may be one of the pivotal factors for cell cycle arrest and apoptosis after treatment of iso-suillin in A549 cells. Moreover, in an A549 xenograft model, tumor growth and progression could be inhibited by iso-suillin. Body weight change and some vital organs toxicity was also roughly examined, no significant toxic effects of iso-suillin were shown (at a dose of 5 mg/kg for each administration). The in vitro and in vivo anti-tumor effects implied that iso-suillin may act as a tumor growth inhibitor, and its induction of p53 phosphorylation is pivotal for cell cycle arrest and apoptosis in A549 cells.
Subject(s)
Diterpenes , Phenols , A549 Cells , Carcinoma, Non-Small-Cell Lung/pathology , Cell Cycle Checkpoints/drug effects , Humans , Phosphorylation , Tumor Suppressor Protein p53ABSTRACT
In the present study, hsa-miR-424-5p mimic plasmid and hsa-mir-424-5p inhibitor plasmid were designed and injected into rats respectively, and miRNA control plasmid was also constructed. Models of Type 1 diabetes (T1D) were built. After successful modeling, the expression of hsa-miR-424-5p in lymphocytes was analyzed by RT-PCR. The expression of protein PD-1, T-bet, CXCR3, STING in Th1 lymphocytes and content of IGF-1 in islet tissue were analyzed by flow analysis. The protein levels of SHP2, Rheb, mTORC1, Rictor and Raptor in islet tissue were analyzed by Western blot. The results showed that hsa-miR-424-5p mimic group had the highest expression of hsa-miR-424-5p in lymphocytes. The expression of PD-1 was in hsa-miR-424-5p inhibitor > miRNA control > hsa-miR-424-5p mimic, while the expression of T-bet, CXCR3 and STING was in hsa-miR-424-5p mimic > miRNA control > hsa-miR-424-5p inhibitor. The expression of IGF-1 protein in hsa-miR-424-5p inhibitor group was the highest (32.08%) and hardly expressed in hsa-miR-424-5p mimic group (2.36%). The expression of SHP2, Rheb, mTORC1, Rictor and Raptor of insulin histoproteins were in hsa-miR-424-5p mimic group > miRNA control of > hsa-miR-424-5p inhibitor group, with statistical differences. It indicates that hsa-miR-424-5p binding PD-1 signaling molecules can stimulate the immune effect through the mTORC signaling pathway and participates in the pathogenesis of T1D.
Subject(s)
Diabetes Mellitus, Experimental/immunology , Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 1/immunology , MicroRNAs/immunology , Programmed Cell Death 1 Receptor/immunology , TOR Serine-Threonine Kinases/immunology , Animals , Cell Line , Diabetes Mellitus, Experimental/genetics , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 1/metabolism , Male , MicroRNAs/genetics , MicroRNAs/metabolism , Programmed Cell Death 1 Receptor/genetics , Programmed Cell Death 1 Receptor/metabolism , Rats , Rats, Wistar , Signal Transduction/immunology , TOR Serine-Threonine Kinases/metabolismABSTRACT
OBJECTIVE: To explore the role and molecular mechanism of regulatory T (Treg) cells in type 1 diabetes (T1D). METHODS: Patients with T1D and the healthy volunteers were selected and a number of CD3+ , CD4+ , CD25+ , and CD127- T cells were determined. The rats were divided into the control, T1D model, and Treg infusion (T1D rats were infused with Treg) group. The number of CD4+ , CD8- , and CD25+ T cells in the three groups were determined by flow cytometry. Weight, blood glucose, serum insulin, peptide C, glucagon, and glucagon like peptide 1 in the three groups were also determined. The messenger RNA (mRNA) levels and contents of interleukin (IL)-10, IL-4, transforming growth factor (TGF)-ß, IL-2, IL-17, and IFN-γ in patients with T1D, healthy volunteers, streptozotocin (STZ)-induced T1D rat model, the control rat, and Treg infusion rats were determined by reverse transcription polymerase chain reaction and the enzyme-linked immunosorbent assay, respectively. RESULTS: Treg content in patients with T1D was significantly decreased compared with the control volunteers. Treg content in rats was markedly decreased after injection with STZ to induce T1D rat model, while Treg infusion weakened the decrease. The change scope of weight and blood glucose in the model and Treg group was bigger than the control group, and the change in the infusion group was lighter than the model group. T1D decreased the expressions of IL-10, IL-4, TGF-ß, and IL-2, while Treg infusion weakened the decrease. The expressions of IL-17 and IFN-γ in the T1D group was increased, while Treg infusion weakened the increase. CONCLUSION: Autologous Treg infusion can strengthen the immunologic and islet function to treat T1D which may be via regulating the expression of inflammatory factors.
Subject(s)
Cytokines/genetics , Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 1/therapy , Animals , Cells, Cultured , Diabetes Mellitus, Type 1/immunology , Enzyme-Linked Immunosorbent Assay , Interferon-gamma/genetics , Interleukin-10/genetics , Interleukin-2/genetics , Interleukin-4/genetics , Male , RNA, Messenger/genetics , Rats , Real-Time Polymerase Chain Reaction , T-Lymphocytes, Regulatory , Transforming Growth Factor beta/geneticsABSTRACT
OBJECTIVE: To investigate the role of miR-424 in diabetic nephropathy (DN) and its relationship with Rictor in mammalian target of rapamycin (mTOR) C2/Akt signaling. METHODS: The western blot analysis and real-time polymerase chain reaction were used to determine the differential expression of Rictor, mTOR, and miR-424 in DN rats. The upregulation of miR-424 was achieved by caudal vein injection of miR-424 mimics. The renal lesion was evaluated by hematoxylin-eosin staining (H&E) and periodic acid schiff staining. The dual-luciferase reporter assay was conducted to determine the binding target of miR-424. The effect of miR-424 upregulation on apoptosis was detected by the terminal deoxynucleotidyl transferase-mediated 2-Deoxyuridine-5-Triphosphate (dUTP) nick-end labeling assay and western blot analysis. RESULTS: A significantly lower expression of miR-424 and a significantly higher expression of Rictor and mTOR were found in renal tissues of DN rats. The upregulation of miR-424 improved renal lesion and DN symptoms of blood glucose level, urine protein level, body weight, creatinine level, blood urea nitrogen, and KW/BW ratio. The upregulation of miR-424 could significantly reduce apoptosis rates of tissue cells by decreasing the expression levels of caspase-3 and Bax as well as increasing the level of Bcl-2. Furthermore, Rictor was the direct target for miR-424, and upregulation of miR-424 inhibited Rictor through Akt signaling in renal tissue of DN rats and high-glucose-treated human glomerular mesangial cells. CONCLUSION: miR-424 contributes to alleviating the symptoms in DN rat models by targeting Rictor through mTORC2/Akt signaling.
Subject(s)
Diabetic Nephropathies/genetics , Mechanistic Target of Rapamycin Complex 2/metabolism , MicroRNAs/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Rapamycin-Insensitive Companion of mTOR Protein/metabolism , Signal Transduction , Up-Regulation/genetics , Animals , Apoptosis/drug effects , Apoptosis/genetics , Base Sequence , Blood Glucose/metabolism , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/genetics , Diabetic Nephropathies/blood , Diabetic Nephropathies/physiopathology , Disease Models, Animal , Down-Regulation/drug effects , Down-Regulation/genetics , Glucose/toxicity , Humans , Kidney Function Tests , Male , Mesangial Cells/drug effects , Mesangial Cells/metabolism , MicroRNAs/genetics , Rats, Sprague-Dawley , Signal Transduction/drug effects , Up-Regulation/drug effectsABSTRACT
OBJECTIVE: Whether obesity categories can be used to predict cardiovascular disease (CVD) in Chinese adults remains unclear. This aim of this study was to examine the predictive values of obesity categories for CVD risk factors in Chinese adults. METHODS: This study comprised a sample size of 3480 men and 6364 women aged ≥25 years (age range 25-89 years), from the medical health check-up center of Lianyungang First People's Hospital. The following CVD risk factor outcomes were used: hypertension, diabetes, dyslipidemia, insulin resistance, and metabolic syndrome (Mets). Framingham risk scores were used to evaluate the CVD. Four categories of obesity were used, based on body mass index (BMI) and waist circumference: no risk, increased risk, high risk, and very high risk. Predictive abilities were determined by calculating the odds ratios (OR) of CVD risk. RESULTS: A graded linear relationship between obesity categories and CVD risk was observed across the categories, except for dyslipidemia. The people in the very high-risk category had the highest OR of having more unfavorable CVD risk factors compared with those in the lower risk category. For example, the OR of diabetes increased with the increase in risk category (OR, 1.13, 1.36, and 1.83, respectively, for increased, high, and very high risk categories in men and OR, 1.52, 1.80, and 2.78, respectively, for increased, high, and very high risk category in women). CONCLUSIONS: These findings suggest that obesity categories provide clinical insights into identifying multiple CVD risk factors in Chinese adults.
ABSTRACT
This study aims to test the role of E2F1-topoIIß signaling in neuronal differentiation of SH-SY5Y cells. With retinoic acid (RA) induction, a high percentage of cells were found to be arrested at the G0/G1 phase, with decreased levels of cyclinD1, CDK4, phosphorylation status of pRb and E2F1, in addition to an elevated level of p27. The cells were shown to differentiate into neuronal phenotypes characterized by highly expressed neuronal markers, MAP2 and enriched topoIIß, and remarkable neurite outgrowth. Exogenously forced E2F1 expression with a specific E2F1 plasmid led to suppression of topoIIß expression and disruption of the neuronal differentiation of SH-SY5Y cells. On further examination using the ChIP assay, we found that E2F1 bound directly to the promoter region of topoIIß, and its binding ability was inversely correlated with topoIIß expression in response to RA induction. Thus, our findings suggest that E2F1-topoIIß signaling may play a role in regulation of cell cycle exit and neuronal differentiation.
Subject(s)
Cell Differentiation/genetics , DNA Topoisomerases, Type II/genetics , E2F1 Transcription Factor/genetics , Neurons/metabolism , Poly-ADP-Ribose Binding Proteins/genetics , Cell Cycle/genetics , Cell Line , Cyclin D1/genetics , Cyclin-Dependent Kinase 4/genetics , Gene Expression Regulation, Developmental , Humans , Microtubule-Associated Proteins/genetics , Promoter Regions, Genetic , Protein Binding/genetics , Retinoblastoma Protein/genetics , Signal Transduction/genetics , Tretinoin/pharmacologyABSTRACT
OBJECTIVES: The primary objective of this study was to investigate whether dexmedetomidine could potentiate the analgesic efficacy of ropivacaine, when added to ropivacaine for wound infiltration in patients undergoing open gastrectomy. METHODS: Fifty patients scheduled for open gastrectomy were divided into 2 equal groups that were received wound infiltration using 20âmL 0.3% ropivacaine plus 2âmL normal saline (group R) or 20âmL 0.3% ropivacaine plus 2âmL 1.0âµg/kg dexmedetomidine (group DR). Visual analogue scale (VAS) pain score, patient-controlled analgesia (PCA) pump press number, sufentanil consumption, postoperative nausea and vomiting (PONV), and wound healing score were recorded. RESULTS: The VAS pain score were comparable between the 2 groups at the observation time points (Pâ>â.05), PCA pump press number and sufentanil consumption were higher in group R than that in group DR at 0 to 2, 2 to 4, 4 to 6 time intervals (Pâ<â.05) except for 6 to 8, 8 to 10, 10 to 12 time intervals (Pâ>â.05), meanwhile, the 24âhours total sufentanil consumption was also higher in group R than that in group DR (90.4â±â20.5 vs 79.2â±â9.4) (Pâ<â.05), there were no significant differences in PONV and wound healing score between the 2 groups (Pâ>â.05). CONCLUSIONS: Dexmedetomidine as an adjuvant to ropivacaine for wound infiltration promoted the analgesic efficacy of ropivacaine, reduced sufentanil consumption, and had no effect on wound healing; it could be as an ideal adjuvant which could potentiate the analgesic efficacy of local anesthetics.
Subject(s)
Amides/administration & dosage , Analgesics/administration & dosage , Anesthetics, Local/administration & dosage , Dexmedetomidine/administration & dosage , Gastrectomy/methods , Adult , Aged , Analgesia, Patient-Controlled/statistics & numerical data , Chemotherapy, Adjuvant/methods , Double-Blind Method , Female , Humans , Male , Middle Aged , Pain Measurement , Pain, Postoperative/epidemiology , Pain, Postoperative/prevention & control , Postoperative Nausea and Vomiting/epidemiology , Prospective Studies , Ropivacaine , Sufentanil/administration & dosage , Treatment Outcome , Wound Healing/drug effectsABSTRACT
Topoisomerase IIß (topoIIß) is a nuclear enzyme specifically expressed in neurons, and plays an important role in the development of the cerebellum. To date, the expression of topoIIß protein in medulloblastoma (MB) has not been investigated. In this study, 16 MB specimens including 10 classical subtypes of MB and 6 desmoplastic subtypes of MB (DMB), along with 5 normal cerebellum samples, were obtained from clinics. With immunohistochemical staining, prominently expressed topoIIß was seen in normal cerebellar tissues, while there was no or less pronounced staining in classical MB cells. Interestingly, on comparing topoIIß expression in different regions of DMB samples, relatively high levels of topoIIß were revealed within nodules composed of differentiated neurocytic cells, which are known to predict a favorable clinical outcome for MB. We also examined the expression of two epigenetic factors, H3K27me3 and JMJD3 in the different tissues. Very high levels of H3K27me3 were found in all MB samples, except the intranodules of DMB, where JMJD3 expression was more prominent. Furthermore, a negative correlation between topoIIß and H3K27me3 in MB was revealed in this study. Thus, our data primarily indicate that topoIIß can be used to estimate neuronal differentiation in MB, and may serve as a target for improving the survival rates for this condition. We speculate that H3K27me3 repression of topoIIß at the transcriptional level may occur, although this needs to be verified using larger numbers of MB samples in future experiments.
Subject(s)
Biomarkers, Tumor/analysis , Cerebellar Neoplasms/pathology , DNA Topoisomerases, Type II/biosynthesis , Medulloblastoma/pathology , Adolescent , Cell Differentiation/physiology , Child , Child, Preschool , Female , Histones/biosynthesis , Humans , Immunohistochemistry , Jumonji Domain-Containing Histone Demethylases/biosynthesis , MaleABSTRACT
BACKGROUND: The suillin isoform iso-suillin is a natural substance isolated from a petroleum ether extract of the fruiting bodies of the mushroom Suillus flavus. Previous studies have found its inhibition effect on some cancer cells, and we aimed to study its effects on human small cell lung cancer H446 cell line. METHODS: Cell viability was measured by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. Cellular morphological changes (apoptosis and necrosis) were evaluated using an electron microscope and Hoechst 33258 staining detected by the inverted microscope. Flow cytometry was used to detect cell apoptosis, cell cycle distribution, and mitochondrial membrane potential. Protein expression was determined by Western blotting analysis. RESULTS: Here, we describe the ability of iso-suillin to inhibit the growth of H446 cells in time- and dose-dependent way. Iso-suillin had no obvious impact on normal human lymphocyte proliferation at low concentrations (9.09, 18.17, or 36.35 µmol/L) but promoted lymphocyte proliferation at a high concentration (72.70 µmol/L). After treatment of different concentrations of iso-suillin (6.82, 13.63, or 20.45 µmol/L), the apoptosis rate of H446 cells increased with increasing concentrations of iso-suillin (16.70%, 35.54%, and 49.20%, respectively, all P < 0.05 compared with the control), and the expression of related apoptotic proteins in the mitochondrial pathway including cytochrome c and caspase-9 were up-regulated compared with the control (all P < 0.05). On the contrary, Bcl-2/Bax ratio was down-regulated compared with the control. Besides, the expression of pro-apoptotic proteins in the death receptor apoptosis pathway, including Fas-associating protein with a novel death domain and caspase-8, and the expression of caspase-3, a downstream regulatory protein of apoptosis, were also increased compared with the control (all P < 0.05). Inhibitors of caspase-9 and caspase-8 reversed the apoptosis process in H446 cells to varying degrees. CONCLUSIONS: These results suggest that iso-suillin could induce H446 cell apoptosis through the mitochondrial pathway and the death-receptor pathway. Therefore, iso-suillin might have a potential application as a novel drug for lung cancer treatment.
Subject(s)
Diterpenes/pharmacology , Phenols/pharmacology , Animals , Apoptosis/drug effects , Caspase 3/metabolism , Caspase 8/metabolism , Caspase 9/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Cytochromes c/metabolism , Flow Cytometry , Humans , Mice , Small Cell Lung CarcinomaABSTRACT
Tetramethylpyrazine (TMP) is an active compound extracted from the traditional Chinese medicinal herb Chuanxiong. Previously, we have shown that TMP induces human SH-SY5Y neuroblastoma cell differentiation toward the neuronal phenotype by targeting topoisomeraseIIß (TopoIIß), a protein implicated in neural development. In the present study, we aimed to elucidate whether the transcriptional factors specificity protein 1 (Sp1) and nuclear factor Y (NF-Y), in addition to the upstream signaling pathways ERK1/2 and PI3K/Akt, are involved in modulating TopoIIß expression in the neuronal differentiation process. We demonstrated that SH-SY5Y cells treated with TMP (80µM) terminally differentiated into neurons, characterized by increased neuronal markers, tubulin ßIII and microtubule associated protein 2 (MAP2), and increased neurite outgrowth, with no negative effect on cell survival. TMP also increased the expression of TopoIIß, which was accompanied by increased expression of Sp1 in the differentiated neuron-like cells, whereas NF-Y protein levels remained unchanged following the differentiation progression. We also found that the phosphorylation level of Akt, but not ERK1/2, was significantly increased as a result of TMP stimulation. Furthermore, as established by chromatin immunoprecipitation (ChIP) assay, activation of the PI3K/Akt pathway increased Sp1 binding to the promoter of the TopoIIß gene. Blockage of PI3K/Akt was shown to lead to subsequent inhibition of TopoIIß expression and neuronal differentiation. Collectively, the results indicate that the PI3K/Akt/Sp1/TopoIIß signaling pathway is necessary for TMP-induced neuronal differentiation. Our findings offer mechanistic insights into understanding the upstream regulation of TopoIIß in neuronal differentiation, and suggest potential applications of TMP both in neuroscience research and clinical practice to treat relevant diseases of the nervous system.
Subject(s)
DNA Topoisomerases, Type II/metabolism , DNA-Binding Proteins/metabolism , Neurons/enzymology , Pyrazines/pharmacology , Signal Transduction , CCAAT-Binding Factor/metabolism , Cell Line, Tumor , Cell Transdifferentiation , DNA Topoisomerases, Type II/genetics , DNA-Binding Proteins/genetics , Drug Evaluation, Preclinical , G1 Phase Cell Cycle Checkpoints , Gene Expression , Humans , Phenotype , Phosphatidylinositol 3-Kinases/metabolism , Promoter Regions, Genetic , Protein Binding , Protein Processing, Post-Translational , Proto-Oncogene Proteins c-akt/metabolism , Sp1 Transcription Factor/metabolism , Transcriptional ActivationABSTRACT
BACKGROUND: Although a few studies have been reported on predictive factors of postoperative diabetes remission, the conclusions remain inconsistent. This meta-analysis aimed to assess the preoperative clinical factors for type 2 diabetes mellitus (T2DM) remission after bariatric surgery. METHODS: The Cochrane Library, PubMed, MEDLINE, Embase, and CINAHL databases were searched. All human studies published in English between 1 January 1992 and 1 September 2013 reporting on the parameters of interest were included. RESULTS: In total, 15 studies involving 1,753 bariatric surgery patients were selected. Analyses were performed separately for the parameters of interest. T2DM remission was observed to be negatively correlated with age, diabetes duration, insulin use, and HbA1c levels. Baseline body mass index (BMI) and C-peptide levels were positively associated with the remission rate in Asian patients. However, there was no significant association between gender and remission rate. CONCLUSIONS: Patients with younger age, short diabetes duration, better glucose control, and better ß cell function were more likely to achieve T2DM remission after bariatric surgery. However, further randomized controlled trials with uniform remission criteria should be conducted to provide more reliable evidence.
Subject(s)
Diabetes Mellitus, Type 2/surgery , Adult , Age Factors , Bariatric Surgery , Blood Glucose/analysis , Diabetes Mellitus, Type 2/blood , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Remission Induction , Time FactorsABSTRACT
Topoisomerase IIß (top IIß) is a nuclear enzyme with an essential role in neural development. The regulation of top IIß gene expression during neural differentiation is poorly understood. Functional analysis of top IIß gene structure displayed a GC box sequence in its transcription promoter, which binds the nuclear transcription factor specificity protein 1 (Sp1). Sp1 regulates gene expression via multiple mechanisms and is essential for early embryonic development. This study seeks to determine whether Sp1 regulates top IIß gene expression during neuronal differentiation. For this purpose, human neuroblastoma SH-SY5Y cells were induced to neuronal differentiation in the presence of all-trans retinoic acid (RA) for 5 days. After incubation with 10 µM RA for 3-5 days, a majority of the cells exited the cell cycle to become postmitotic neurons, characterized by the presence of longer neurite outgrowths and expression of the neuronal marker microtubule-associated protein-2 (MAP2). Elevated Sp1 and top IIß mRNA and protein levels were detected and found to be positively correlated with the differentiation stage. Chromatin immunoprecipitation assay demonstrated an increased recruitment of Sp1 to the top IIß promoter after RA treatment. Mithramycin A, a compound that interferes with Sp1 binding to GC-rich DNA sequences, downregulated the expression of top IIß, resulting in reduced expression of MAP2 and decreased neurite length compared with the control group. Our results indicate that Sp1 regulates top IIß expression by binding to the GC box of the gene promoter during neuronal differentiation in SH-SY5Y cells.
Subject(s)
Cell Differentiation/physiology , DNA Topoisomerases, Type II/metabolism , DNA-Binding Proteins/metabolism , Gene Expression Regulation, Neoplastic/physiology , Neurons/metabolism , Sp1 Transcription Factor/metabolism , Cell Cycle/drug effects , Cell Differentiation/drug effects , Cell Division/drug effects , Cell Line, Tumor , Chromatin Immunoprecipitation , DNA Topoisomerases, Type II/genetics , DNA-Binding Proteins/genetics , Gene Expression Regulation, Neoplastic/drug effects , Humans , Keratolytic Agents/pharmacology , Neurites/drug effects , Neurites/physiology , Neuroblastoma/pathology , Neurons/cytology , Protein Binding/drug effects , Protein Binding/physiology , RNA, Messenger/metabolism , Sp1 Transcription Factor/genetics , Tretinoin/pharmacologyABSTRACT
Iso-suillin, a natural product isolated from Suillus luteus, has been shown to inhibit the growth of some cancer cell lines. However, the molecular mechanisms of action of this compound are poorly understood. The purpose of this study was to investigate how iso-suillin inhibits proliferation and induces apoptosis in a human hepatoma cell line (SMMC-7721). We demonstrated the effects of iso-suillin on cell proliferation and apoptosis in SMMC-7721 cells, with no apparent toxicity in normal human lymphocytes, using colony formation assays and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis. Western blotting was used to examine the expression of G1 phase-regulated and apoptosis-associated protein levels in iso-suillin treated SMMC-7721 cells. The results indicated that iso-suillin significantly decreased viability, induced G1 phase arrest and triggered apoptosis in SMMC-7721cells. Taken together, these results suggest the potential of iso-suillin as a candidate for liver cancer treatment.
Subject(s)
Agaricales/metabolism , Apoptosis/drug effects , Carcinoma, Hepatocellular/drug therapy , Diterpenes/pharmacology , G1 Phase Cell Cycle Checkpoints/drug effects , Phenols/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Drug Evaluation, Preclinical , Humans , Liver Neoplasms/drug therapy , Lymphocytes/drug effects , Membrane Potential, Mitochondrial/drug effects , Protein Isoforms/pharmacologyABSTRACT
Premature ovarian failure (POF) contributes to amenorrhoea, infertility, early onset of menostasia and osteoporosis. This study profiled differentially expressed miRNAs for association with POF development. Ovarian tissue samples from 4-vinylcyclohexene diepoxide (VCD)-induced rat POF and normal rats were profiled for differentially expressed miRNAs using miRNA microarrays. A total of 63 miRNAs were up-regulated and 20 miRNAs were down-regulated in rat POF tissues versus the control tissues. qRT-PCR verified some of these altered miRNAs, i.e. miR-29a and miR-144 were down-regulated in POF tissues, which may target expression of PLA2G4A that is involved in prostaglandin biosynthesis, whereas miR-27b and miR-190 were up-regulated in POF tissues by negative control of PAPPA and CCL2 expression, respectively, both of which have been shown to relate to response to hormone stimulus. Moreover, the up-regulated miR-151 and miR-672 can also target expression of TNFSF10 and FNDC1, which have been shown to positively regulate cell apoptosis. Profiling of differentially expressed miRNAs in POF provided a novel insight into the molecular events involving the role of miRNAs in POF development with specific emphasis upon miR-27b, miR-190, miR-151, miR-672, miR-29a and miR-144.
Subject(s)
Gene Expression Profiling , MicroRNAs/genetics , Primary Ovarian Insufficiency/genetics , Animals , Disease Models, Animal , Female , Gene Regulatory Networks , Humans , Microarray Analysis , Primary Ovarian Insufficiency/pathology , Rats , Rats, Sprague-DawleyABSTRACT
Genistein (4', 5, 7-trihydroxyisoflavone) is an isoflavone compound obtained from plants that has potential applications in cancer therapy. However, the molecular mechanism of the action of genistein on cancer cell apoptosis is not well known. In this study, we investigated the effect of genistein on topoisomerase II-alpha (Topo IIalpha), an important protein involved in the processes of DNA replication and cell proliferation. The results revealed that inhibition of Topo IIalpha expression through the regulation of Specificity protein 1 and Specificity protein 3 may be one of the reasons for genistein's induction of HeLa cell apoptosis.