Fructose overconsumption impairs hepatic manganese homeostasis and ammonia disposal.

Arginase, a manganese (Mn)-dependent enzyme, is indispensable for urea generation and ammonia disposal in the liver. The potential role of fructose in Mn and ammonia metabolism is undefined. Here we demonstrate that fructose overconsumption impairs hepatic Mn homeostasis and ammonia disposal in male mice. Fructose overexposure reduces liver Mn content as well as its activity of arginase and Mn-SOD, and impairs the clearance of blood ammonia under liver dysfunction. Mechanistically, fructose activates the Mn exporter Slc30a10 gene transcription in the liver in a ChREBP-dependent manner. Hepatic overexpression of Slc30a10 can mimic the effect of fructose on liver Mn content and ammonia disposal. Hepatocyte-specific deletion of Slc30a10 or ChREBP increases liver Mn contents and arginase activity, and abolishes their responsiveness to fructose. Collectively, our data establish a role of fructose in hepatic Mn and ammonia metabolism through ChREBP/Slc30a10 pathway, and postulate fructose dietary restriction for the prevention and treatment of hyperammonemia.

ChREBP-regulated lipogenesis is not required for the thermogenesis of brown adipose tissue.

OBJECTIVES: Brown adipose tissue (BAT) plays a critical role in energy expenditure by uncoupling protein 1 (UCP1)-mediated thermogenesis and represents an important therapeutic target for metabolic diseases. Carbohydrate response element-binding protein (ChREBP) is a key transcription factor regulating de novo lipogenesis, and its activity is associated with UCP1 expression and thermogenesis in BAT. However, the exact physiological role of endogenous ChREBP in BAT thermogenesis remains unclear. METHODS: We used the Cre/LoxP system to generate ChREBP BAT-specific knockout mice, and examined their BAT thermogenesis under acute cold exposure and long-term cold acclimation. Gene expression was analyzed at the mRNA and protein levels, and lipogenesis was examined by 3H-H2O incorporation assay. RESULTS: The mice lacking ChREBP specifically in BAT displayed a significant decrease in the expression levels of lipogenic genes and the activity of de novo lipogenesis in BAT after cold exposure, with UCP1 expression decreased under thermoneutral conditions or after acute cold exposure but not chronic cold acclimation. Unexpectedly, BAT-specific ChREBP deletion did not significantly affect body temperature as well as local temperature or morphology of BAT after acute cold exposure or chronic cold acclimation. Of note, ChREBP deletion mildly aggravated glucose intolerance induced by a high-fat diet. CONCLUSIONS: Our work indicates that ChREBP regulates de novo lipogenesis in BAT and glucose tolerance, but is not required for non-shivering thermogenesis by BAT under acute or long-term cold exposure.

Enhancement of Clathrate Hydrate Formation Kinetics Using Carbon-Based Material Promotion.

Although hydrate-based technology has been considered as a safe and environmentally friendly approach for gas storage and transportation in recent decades, there are still inherent problems during hydrate production, such as a long induction time, slow formation kinetics, and limited hydrate storage capacity. Attempts to resolve these issues have resulted in the development of various kinetics promoters, among which carbon-based materials have become one of the most attractive owing to their unique promotion effect. Herein, results on promotion by bulk wetted carbon materials in the forms of a packed bed, carbon particles in a suspension, and nano-carbon materials in a nanofluid are collected from the published literature. Meanwhile, the promotion mechanisms and influencing factors of the carbon-based promoters are discussed. The purpose of this mini-review is to summarize recent advances and highlight the prospects and future challenges for the use of carbon-based materials in hydrate production.

Liver ChREBP Protects Against Fructose-Induced Glycogenic Hepatotoxicity by Regulating L-Type Pyruvate Kinase.

Excessive fructose consumption is closely linked to the pathogenesis of metabolic disease. Carbohydrate response element-binding protein (ChREBP) is a transcription factor essential for fructose tolerance in mice. However, the functional significance of liver ChREBP in fructose metabolism remains unclear. Here, we show that liver ChREBP protects mice against fructose-induced hepatotoxicity by regulating liver glycogen metabolism and ATP homeostasis. Liver-specific ablation of ChREBP did not compromise fructose tolerance, but rather caused severe transaminitis and hepatomegaly with massive glycogen overload in mice fed a high-fructose diet, while no obvious inflammation, cell death, or fibrosis was detected in the liver. In addition, liver ATP contents were significantly decreased by ChREBP deficiency in the fed state, which was rendered more pronounced by fructose feeding. Mechanistically, liver contents of glucose-6-phosphate (G6P), an allosteric activator of glycogen synthase, were markedly increased in the absence of liver ChREBP, while fasting-induced glycogen breakdown was not compromised. Furthermore, hepatic overexpression of LPK, a ChREBP target gene in glycolysis, could effectively rescue glycogen overload and ATP reduction, as well as mitigate fructose-induced hepatotoxicity in ChREBP-deficient mice. Taken together, our findings establish a critical role of liver ChREBP in coping with hepatic fructose stress and protecting from hepatotoxicity by regulating LPK.

DDX10 overexpression predicts worse prognosis in osteosarcoma and its deletion prohibits cell activities modulated by MAPK pathway.

Osteosarcoma (OS) is an invasive cancer in the skeletal system. The molecular mechanism of its etiology and pathogenesis are still not clear, so the effective treatment strategy of OS needs further research. First, we analyzed the expression level and prognostic ability of the RNA helicase DDX10 in OS patients based on the data obtained from GEO database. Next, we used CCK8 to test OS cell viability. Besides, we used wound-healing assay and transwell migration assay to detect cell migration of OS MG63 cell line. And the cell invasion was tested by transwell invasion assay. Moreover, we used QRT-PCR and western blot to analyze the mRNA and protein expression levels. We found that DDX10 was significantly over-expressed in OS patients and elevated level of DDX10 was associated with a poor prognosis. Silencing of DDX10 inhibited proliferation, invasion and migration of MG63 cells in vitro. Down-regulation of DDX10 inhibited MAPK signaling pathway. The expression of p-MEK and p-ERK were also decreased by silencing of DDX10. Therefore, Silencing of DDX10 inhibited proliferation, invasion and migration of MG63 cells, which might be regulated by suppression of MAPK pathway. In conclusion, our results unfold a novel area of studying for understanding how DDX10 functions in OS oncogenic and prognostic significance, accordingly implying a promising therapeutic target for OS treatment.

ZBTB20 regulates EGFR expression and hepatocyte proliferation in mouse liver regeneration.

Liver has a unique regenerative capacity, however, its regulatory mechanism is not fully defined. We have established the zinc-finger protein ZBTB20 as a key transcriptional repressor for alpha-fetoprotein (AFP) gene in liver. As a marker of hepatic differentiation, AFP expression is closely associated with hepatocyte proliferation. Unexpectedly, here we showed that ZBTB20 acts as a positive regulator of hepatic replication and is required for efficient liver regeneration. The mice specifically lacking ZBTB20 in hepatocytes exhibited a remarkable defect in liver regeneration after partial hepatectomy, which was characterized by impaired hepatocyte proliferation along with delayed cyclin D1 induction and diminished AKT activation. Furthermore, we found that epithelial growth factor receptor (EGFR) expression was dramatically reduced in the liver in the absence of ZBTB20, thereby substantially attenuating the activation of EGFR signaling pathway in regenerating liver. Adenovirus-mediated EGFR overexpression in ZBTB20-deficient hepatocytes could largely restore AKT activation in response to EGFR ligands in vitro, as well as hepatocyte replication in liver regeneration. Furthermore, ZBTB20 overexpression could significantly restore hepatic EGFR expression and cell proliferation after hepatectomy in ZBTB20-deficient liver. Taken together, our data point to ZBTB20 as a critical regulator of EGFR expression and hepatocyte proliferation in mouse liver regeneration, and may serve as a potential therapeutic target in clinical settings of liver regeneration.

Knockin of Cre Gene at Ins2 Locus Reveals No Cre Activity in Mouse Hypothalamic Neurons.

The recombination efficiency and cell specificity of Cre driver lines are critical for exploring pancreatic ß cell biology with the Cre/LoxP approach. Some commonly used Cre lines are based on the short Ins2 promoter fragment and show recombination activity in hypothalamic neurons; however, whether this stems from endogenous Ins2 promoter activity remains controversial. In this study, we generated Ins2-Cre knockin mice with a targeted insertion of IRES-Cre at the Ins2 locus and demonstrated with a cell lineage tracing study that the Ins2 gene is not transcriptionally active in the hypothalamus. The Ins2-Cre driver line displayed robust Cre expression and activity in pancreatic ß cells without significant alterations in insulin expression. In the brain, Cre activity was mainly restricted to the choroid plexus, without significant recombination detected in the hippocampus or hypothalamus by the LacZ or fluorescent tdTomato reporters. Furthermore, Ins2-Cre mice exhibited normal glucose tolerance and insulin secretion upon glucose stimulation in vivo. In conclusion, this Ins2-Cre driver line allowed high-fidelity detection of endogenous Ins2 promoter activity in vivo, and the negative activity in the hypothalamus demonstrated that this system is a promising alternative tool for studying ß cell biology.

[Confirmative factor analysis in the health literacy questionnaire and its applications in Chinese residents].

OBJECTIVE: To evaluate construct validity of China residents health literacy questionnaire and explore the application of confirmative factor analysis (CFA) in health literacy measurements. METHODS: CFA was performed on dimension of basic healthy skills in the questionnaire. Latent variable scores and comprehensive score based on factor variance weight were calculated. Comparison among the latent variable scores, comprehensive scores and proportion of knowing was conducted via GLM or Logistic model. RESULTS: Two factors named general capacity and emergency capacity were well fitted (chi(2)=12.12, P=0.356, IFI=0.998, TLI=0.996, RMSEA=0.007). According to comprehensive score the sample qualification rate of basic health literacy was 38.5%(785/2 040), much similar to 38.2% (780/2 040) which is calculated by original item scores. Latent variable score or comprehensive score has more statistical power than that of proportion of knowing in multivariate analysis. CONCLUSION: CFA is a useful tool and valuable for applying in the field of health literacy measurement and analysis.

[Sexual physiology and psychology of male college students and their clinical significance].

OBJECTIVE: To understand the sexual physiology and psychology of male college students and to provide schools, families and the society with reference for the sexual physiological and psychological education among college students as well as for the diagnosis and treatment of their sexual psychological disorders in Jiangsu. METHODS: An investigation was conducted by using a questionnaire on sexual physiology and psychology among randomly selected 3786 male college students from 18 universities in Jiangsu. RESULTS: As regards sexual education, 5.49% of the subjects were satisfied with their schools, 78.18% wanted it to be strengthened and 68.36% obtained their sexual knowledge from the internet. Concerning sexual physiology, 68.78% experienced their first spermatorrhea at the age of 12-15. As for sexual psychology, 85.79% loved a certain female inwardly, and 70.99% experienced love affairs. With regard to sexual activity, 25.54% had sexual experience. CONCLUSION: College students nowadays are relatively open in sexual ideology, immature in sexual psychology and lacking in sexual knowledge, while schools are inefficient in sexual education. Their sexual health calls for joint attention from schools, families and the society, particularly schools, which need to establish special offices for research and education on sexual health.

[Observation on the safety: clinical trail on intracoronary autologous bone marrow mononuclear cells transplantation for acute myocardial infarction].

OBJECTIVE: To investigate the safety of autologous bone marrow mononuclear cell (BM-MNCs) transplantation by intracoronary infusion in patients with acute myocardial infarction (AMI). METHODS: One hundred and eighty-four patients with AMI treated with percutaneous coronary intervention (PCI) were randomized in a 1:1 way to either intracoronary transplantation of autologous BM-MNCs (n = 92) right after PCI or to sodium chloride concluding heparin (controlled, n = 92) via a micro infusion catheter. In the process of the intracoronary infusion of BM-MNCs, the complications should be recorded, which were aberration reflect (including of pale, syncope, nausea, hypotension and shock), deterioration of angina or heart failure, arrhythmias (including of bradycardia, sinus arrest or atrial ventricular block or ventricular fibrillation), embolism etc. Body temperature, blood pressure and heart rates should be monitored during the first week after transplantation. Holter, coronary angiography and ultrasonic cardiography were performed at the designed time points. Main heart accidents, restenosis and tumor were recorded during 2-years follow up. RESULTS: During the period of bone marrow puncture and intracoronary infusion of BM-MNCs, few patients occurred pale, dizziness, bradycardia and hypotension, which were transient and due to vagus reflect. No stem cell-related arrhythmias, deterioration of angina were noted. In BM-MNCs group one patient developed in-stent reocclusion in one week after transplantation, five developed in-stent restenosis during further follow-up 30 months, which were similar with control group. There were no deaths, major adverse cardiac events, tumor and other late adverse events during follow-up period in both groups. CONCLUSION: Intracoronary transplantation of autologous BM-MNCs in the acute phase after AMI is feasible and seems safe in the 30 months of follow-up.

Treatment of osteonecrosis of the femoral head by percutaneous decompression and autologous bone marrow mononuclear cell infusion.

OBJECTIVE: To evaluate the clinical efficacy and safety of the treatment of osteonecrosis of the femoral head by percutaneous decompression and autologous bone marrow mononuclear cell (BMCs) infusion. METHODS: 44 hips in 28 patients with avascular necrosis at early stage were treated by percutaneous multiple holes decompression followed by autologous BMCs infusion. Autologous BMCs were concentrated from bone marrow that was taken from the posterior iliac crest of the patient. Patients were followed up at least 2 years. The results were determined by the changes in the Harris hip score and the progression in the radiograghic stages. RESULTS: No complications were observed after the operation. Before operation, there were stage I of femoral head necrosis in 8 hips, stage II in 15 hips, stage III in 14 hips, stage IV in 7 hips, and the postoperative stages at the most recent follow-up were stage O in 1 hip, stage I in 6 hips, stage II in 13 hips, stage III in 13 hips, stage IV in 7 hips, stage V in 4 hips. The mean preoperative Harris hip score was 58 (46-89), and improved to 86 (70-94) postoperatively. All the femoral head collapsed preoperatively showed that the necrotic size was at least more than 30%. CONCLUSIONS: Percutaneous multiple holes decompression combined with autologous BMCs is a new way to treat avascular necrosis of the femoral head. The earlier the stage, the better the result. A randomized prospective study needed to compare with routine core decompression in the future.

Impact of pathogen burden on in-stent restenosis in patients after coronary stent implantation.

BACKGROUND: Although some certain infectious pathogens could be detected in the patients with coronary artery disease, the roles of these infectious factors in the development of coronary artery diseases remain largely unknown. Since the number of infectious pathogens has been argued to be relative to the coronary artery diseases, we therefore examined whether there is a link between the number of infections and the incidence of in-stent restenosis after stent implantation. METHODS: One hundred and eighty-one patients were enrolled in this study. Infectious pathogens including serum anti-Chlymydia pneumoniae, cytomegalovirus, Helico pylori, human herpes simplex virus-1, human herpes simplex virus-2 antibodies and hepatitis B virus antigen were measured in all patients before coronary stent implantation. Coronary angiography was performed before, immediately after and 6 months after stent implantation. RESULTS: Restenosis rate 6 months post stent implantation was similar in patients with low pathogen burden (< 3 pathogens, 33.3%) to those with high pathogen burden (> or = 3 pathogens, 29.1%). CONCLUSIONS: Previous infections with Chlymydia pneumoniae, cytomegalovirus, Helico pylori, human herpes simplex virus-1, human herpes simplex virus-2 and hepatitis B virus do not contribute to the incidence of restenosis after stent implantation.

[Relationship between infection burden and atherosclerosis and plaque feature].

OBJECTIVE: To evaluate the relationship between infection burden and coronary atherosclerosis and the plaque feature. METHODS: One hundred and eighty two patients underwent coronary angiography in Zhongshan Hospital from 2002 - 2003. Atherosclerosis and vulnerable plaque were determined by intravascular ultrasound (IVUS). Seropositivity of cytomegalovirus, helicobacter pylori, chlamydia pneumonia, hepatitis B virus, EB virus, CoxB virus, influenza A virus, influenza B virus and mycobacterium tuberculosis were determined by ELISA. The serum hs-CRP was detected by Dade Behring prospect (Immuno-nehelomitery). Patients were divided into three groups according to the pathogen burden: group A, n or= 6. RESULTS: The pathogen burden was independent of the C-reactive protein level. Increasing pathogen burden was significantly associated with increasing atherosclerosis risk, the prevalence of atherosclerosis was 44.4%, 70.6% and 76.7% in group A, B and C. The risk associated with elevated pathogen burden was much higher when CRP was also elevated (> 5.0 mg/L) (43.8%, 70.0%, 70.8%) vs (45.5%, 63.7%, 96.8%). The positively of vulnerable plaque increased significantly when the pathogen burden was high (n > 5) (33.3%, 32.4% and 51.7% P < 0.05). CONCLUSION: Our data suggested that infection burden was associated with prevalence of coronary atherosclerosis, and it was particularly important when C-reactive protein was elevated. The high level infection burden could predict vulnerable plaque.

[Inhibition of activation of nuclear factor-kappaB enhanced apoptosis of leukemic cells induced by homoharringtonine].

OBJECTIVE: To explore the effects of dexamethasone (DXM) and vincristine (VCR) on apoptosis of K562-n cells and activation of nuclear factor-kappaB-gene binding (NF-kappaB) in K562-n cells induced by homoharringtonine. METHODS: K562-n cells were cultured in RPMI-1640 medium. Homoharringtonine of various concentrations was added into the cultures. Twelve hours later, the apoptosis induced by homoharringtonine in K562-n cells was analysed by TdT-mediated X-dUTP nick and end labeling (TUNEL) and DNA electrophoresis. Another sample of K562-n cells was culture together with DXM (1 micro mol/L) or VCR (0.1 micro mol/L) for 2 hours, then homoharringtonine was added into the cultures. Twelve hours later, the apoptosis in K562-n cells was analysed by TUNEL and DNA electrophoresis. Still another sample of K562-n cells was cultured for 3 hours with homoharringtonine, then electrophoretic mobility shift assay (EMSA) was conducted to determine the DNA-binding activation of NF-kappaB. A fourth sample of K562-n cells was cultured together with DXM (1 micro mol/L) or VCR (0.1 micro mol/L) for 2 hours, then homoharringtonine was added into the cultures. Three hours later, EMSA was conducted. RESULTS: The apoptosis rates of K562-n cells induced by homoharringtonine of various concentrations were (30.00 +/- 3.34)%, (47.13 +/- 3.18)% and (68.63 +/- 8.14)%, respectively. The apoptosis rates of K562-n cells induced by homoharringtonine being pre-processed with DXM or VCR were (55.75 +/- 3.88)% and (64.38 +/- 4.60)%, respectively, being 85.8% and 114.6% higher than that induced by homoharringtonine alone (30.00 +/- 3.34)% (all P < 0.05). Activation of NF-kappaB in K562-n cells was induced significantly by homoharringtonine. Activation of NF-kappaB in K562-n cells induced by homoharringtonine could be suppressed by being pre-processed with 1.0 micro mol/L DXM or 0.1 micro mol/L VCR. The rate of suppression was 32.0% and 39.4% respectively. CONCLUSION: Homoharringtonine induces apoptosis of K562-n cells and induces NF-kappaB activation in K562-n cells. The mechanism of increased apoptosis of K562-n cells with DXM or VCR may be related to suppression of activation of NF-kappaB of K562-n cells.

[Relation between activation of NF-kappa B and chemotherapy induced apoptosis of leukemic cells].

OBJECTIVE: To analyze the relation between activation of NF-kappa B and chemotherapy induced apoptosis of leukemic cells and the effect of vincristine (VCR) on them. METHODS: Electrophoretic mobility shift assay (EMSA) was used to detect the activation of NF-kappa B and tunel DNA electrophoresis was adopted to observe the apoptosis induced by cytosine arabinoside (Ara-C) and etopside (Vp-16) in P388 leukemic cells. RESULTS: The activation of NF-kappa B induced by Ara-C and Vp-16 was obviously correlated to apoptosis in P388 cells. VCR (0.1 micromol/L) could suppress activation of NF-kappa B by 52% and 63% and significantly increase the apoptosis by 89% and 123% as induced by Ara-C (100 micromol/L) and Vp-16 (100 micromol/L). The activity of NF-kappa B could be found in P388 cells before being exposed to chemotherapeutic agent. CONCLUSION: Chemotherapeutic agents can induce apoptosis and activation of NF-kappa B of P388 cells. The mechanism of VCR potentiating chemotherapeutics induction of leukemia cell apoptosis may be related to its suppression of the NF-kappa B activity in the P388 cells.