👤 Ze Ma

Multiple osteochondromas (MO) is an autosomal dominant hereditary disorder caused by heterozygous germline mutations in the exostonsin-1 (EXT1) or exostosin-2 (EXT2) genes. In this study, we screened mutations in the EXT1/EXT2 genes in four Chinese MO kindreds by direct sequencing. Three point mutations were detected, including a nonsense mutation in the EXT2 gene (c.544C > T) and two splice site mutations in the EXT1 and EXT2 genes, respectively (EXT1: c.1883 + 1G > A and EXT2: c.1173 + 1G > T). Although splice site mutations constitute at least 10% of all mutations that cause MO, there has been limited research on their pathogenic effect on RNA processing due to poor availability of patient RNA samples. In this study, ex vivo and in vivo splicing assays were used to investigate the effect of EXT1 and EXT2 mutations on aberrant splicing at the mRNA level. Our results indicate that identified splice site mutations can cause either cryptic splice site usage or exon skipping. Show less

To screen for potential mutations in an ethnic Han Chinese family from Shanxi with hereditary multiple exostoses. Polymerase chain reaction and DNA sequencing were used to screen potential mutations in EXT1 and EXT2 genes. For EXT1 gene, two synonymous mutations (P477P and E587E), three intronic mutations (c.1537 -48A>G, c.1721 +203A>G and c.1722 -103C>G) were detected. For EXT2 gene, five intronic mutations (c.-29 -148A>T, c.1080 -18T>A, c.1336 -93C>T, c.1526 -166C>T, and c.1526 -195C>T) were identified. Among these, EXT1 P477P, EXT1 E587E and EXT2 c.1080 -18T>A are polymorphisms listed by Multiple Osteochondroma Mutation Database, whilst the other 7 sites have not been reported. No mutations have been found among all exons of the EXT1 and EXT2 genes in this family. Linkage analysis is necessary for identifying the cause of this disease. Show less

Past research has reported that single nucleotide polymorphisms (SNPs) in fatty acid desaturase 1 and 2 (FADS1/2) can influence plasma fatty acid (FA) profiles. Changes in FA profiles are known to influence inflammatory processes; therefore both FA and SNPs in FADS1/2 may affect inflammation. The goals of this study were to (i) examine the relationships between individual n-6 FA and estimates of FA desaturation with circulating high sensitivity C-reactive protein (hsCRP) levels, and (ii) determine whether SNPs in FADS1/2 are associated with changes in hsCRP. FA and hsCRP were measured in fasted plasma samples from 878 healthy young adults (20-29yrs). Circulating levels of plasma linoleic (LA), γ-linolenic (GLA), dihomo-γ-linolenic (DGLA) and arachidonic (AA) acids were measured by gas chromatography and used to calculate desaturase indices for FADS1/2. Nineteen SNPs in FADS1/2 were genotyped in all subjects and six (rs174579, rs174593, rs174626, rs526126, rs968567 and rs17831757) were further analyzed. Significant inverse associations were found between LA and hsCRP (p=8.55×10(-9)) and the FADS1 desaturase index and hsCRP (p=4.41×10(-6)). A significant positive association was found between DGLA and hsCRP (p=9.10×10(-11)). Several SNPs were associated with circulating levels of individual FA and desaturase indices, with minor allele carriers having lower AA levels and reduced desaturase indices. A single SNP in FADS2 (rs526126) was weakly associated with hsCRP (p=0.05). This study highlights the relationships between FA and hsCRP, and confirms that FA are strongly influenced by SNPs in FADS1/2. Furthermore, we found weak evidence that SNPs in FADS1/2 may influence hsCRP levels in young adults. Show less

CD133 (Prominin-1/AC133) is generally treated as a cell surface marker found on multipotent stem cells and tumor stem-like cells, and its biological function remains debated. Genetically modified rat glioma cell lines were generated by lentiviral gene delivery of human CD133 into rat C6 glioma cells (hCD133(+) -C6) or by infection of C6 cells with control lentivirus (mock-C6). Stable hCD133 expression promoted the self-renewal ability of C6-formed spheres with an increase in the expression of the stemness markers, Bmi-1 and SOX2. Akt phosphorylation, Notch-1 activation, and Notch-1 target gene expression (Hes-1, Hey1 and Hey2) were increased in hCD133(+) -C6 when compared to mock-C6. The inhibition of Akt phosphorylation, Notch-1 activation, and Hes-1 in hCD133(+) -C6 cells effectively suppressed their clonogenic ability, indicating that these factors are involved in expanding the growth of hCD133(+) -C6. An elevated expression of GTPase-activating protein 27 (Arhgap27) was detected in hCD133(+) -C6. A decline in the invasion of hCD133(+) -C6 by knockdown of Arhgap27 expression indicated the critical role of Arhgap27 in promoting cell migration of hCD133(+) -C6. In vivo study further showed that hCD133(+) -C6 formed aggressive tumors in vivo compared to mock-C6. Exposure of hCD133(+) -C6 to arsenic trioxide not only reduced Akt phosphorylation, Notch-1 activation and Hes-1 expression in vitro, but also inhibited their tumorigenicity in vivo. The results show that C6 glioma cells with stable hCD133 expression enhanced their stemness properties with increased Notch-1/Hes-1 signaling, Akt activation, and Arhgap27 action, which contribute to increased cell proliferation and migration of hCD133(+) -C6 in vitro, as well as progressive tumor formation in vivo. Show less

The Lingo-1 sequence variant has been associated with essential tremor (ET) in several genome-wide association studies. However, the role that Lingo-1 might play in pathogenesis of ET is not understood. Since Lingo-1 protein is a negative regulator of axonal regeneration and neurite outgrowth, it could contribute to Purkinje cell (PC) or basket cell axonal pathology observed in postmortem studies of ET brains. In this study, we used Western blotting and immunohistochemistry to examine Lingo-1 protein in ET vs. control brains. In Western blots, Lingo-1 protein expression level was significantly increased in cerebellar cortex (1.56 ± 0.46 in ET cases vs. 0.99 ± 0.20 in controls, p = 0.002), but was similar in the occipital cortex (p = 1.00) of ET cases vs. controls. Lingo-1 immunohistochemistry in cerebellum revealed that Lingo-1 was enriched in the distal axonal processes of basket cells, which formed a "pinceau" structure around the PC axon initial segment (AIS). We found that some Lingo-1-positive pinceau had abnormally elongated processes, targeting PC axon segments distal to the AIS. In ET cases, the percentage of Lingo-1-positive pinceau that were ≥30 or ≥40 μm in length was increased 2.4- to 4.1-fold, respectively, vs. pinceau seen in control brains (p < 0.0001). Elongated Lingo-1-positive pinceau strongly correlated with number of PC axonal torpedoes and a rating of basket cell axonal pathology. The increased cerebellar Lingo-1 expression and elongated Lingo-1-positive pinceau processes could contribute to the abnormal PC and basket cell axonal pathology and cerebellar dysfunction observed in ET. Show less

Human complex metabolic traits are in part regulated by genetic determinants. Here we applied exome sequencing to identify novel associations of coding polymorphisms at minor allele frequencies (MAFs) >1% with common metabolic phenotypes. The study comprised three stages. We performed medium-depth (8×) whole exome sequencing in 1,000 cases with type 2 diabetes, BMI >27.5 kg/m(2) and hypertension and in 1,000 controls (stage 1). We selected 16,192 polymorphisms nominally associated (p < 0.05) with case-control status, from four selected annotation categories or from loci reported to associate with metabolic traits. These variants were genotyped in 15,989 Danes to search for association with 12 metabolic phenotypes (stage 2). In stage 3, polymorphisms showing potential associations were genotyped in a further 63,896 Europeans. Exome sequencing identified 70,182 polymorphisms with MAF >1%. In stage 2 we identified 51 potential associations with one or more of eight metabolic phenotypes covered by 45 unique polymorphisms. In meta-analyses of stage 2 and stage 3 results, we demonstrated robust associations for coding polymorphisms in CD300LG (fasting HDL-cholesterol: MAF 3.5%, p = 8.5 × 10(-14)), COBLL1 (type 2 diabetes: MAF 12.5%, OR 0.88, p = 1.2 × 10(-11)) and MACF1 (type 2 diabetes: MAF 23.4%, OR 1.10, p = 8.2 × 10(-10)). We applied exome sequencing as a basis for finding genetic determinants of metabolic traits and show the existence of low-frequency and common coding polymorphisms with impact on common metabolic traits. Based on our study, coding polymorphisms with MAF above 1% do not seem to have particularly high effect sizes on the measured metabolic traits. Show less

Hypertrophic cardiomyopathy (HC) is a hereditary heterogeneous cardiovascular disorder. Existing data have been of predominantly Caucasian samples, and a large study is needed in Chinese population. The present study was intended to explore the genetic basis and clinical characteristics correlated with different genotypes in a large cohort of Chinese patients. Direct gene sequencing of β-myosin heavy chain (MYH7), myosin binding protein-C (MYBPC3), and cardiac troponin T (TNNT2) was performed in 136 unrelated Chinese HC patients. Clinical evaluations were conducted. In total, 32 mutations were identified in 36 patients (27%), including 10 novel ones. Distribution of mutations was 56% (MYBPC3), 31% (MYH7), and 13% (TNNT2), respectively. Double mutations were identified in 3% patients. The occurrence of HC-associated sarcomeric mutations was associated with an earlier age of onset, increased left ventricular hypertrophy, a higher incidence of syncope, previous family history, and sudden cardiac death. No statistical difference was identified in patients carrying MYBPC3 and MYH7 mutations with regard to clinical characteristics and outcomes. Patients with double mutations were associated with malignant progression in the study. In conclusion, MYBPC3 is the most predominant gene in HC. Multiple mutations are common in MYH7, MYBPC3, and TNNT2. The present study suggests a large diversity of HC and a prognostic role of genotype. Show less

Studies have shown that inflammation promoted atherosclerotic progression; however, it remains unclear whether inflammation promoted atherosclerotic progression properties by altering cholesterol metabolism in human macrophages. In the present study, we evaluated a potential mechanism of inflammation on atherogenic effects. We evaluated the ability of TNFa to affect Reverse cholesterol transport (RCT) and cholesterol uptake and its mechanism(s) of action in human macrophages. We initially determined the potential effects of TNFa on cholesterol efflux in the human macrophages. We also determined alterations in mRNA and protein levels of ABCA1, ABCG1, LXRa, CD-36, SR-A in human macrophages using quantitative real-time polymerase chain reaction (PCR) and Western immunoblot analyses. The cholesterol efflux rate and protein expression of ABCA1, ABCG1, LXRa, CD-36, SR-A were quantified in human macrophages under PKC-θ inhibition using PKC-θ siRNA. Our results showed that TNFa inhibited the rate of cholesterol efflux and down-regulation the expression levels of ABCA1, ABCG1 and LXRa and up-regulation the expression levels of CD-36, SR-A in human macrophages; PKC-θ inhibition by PKC-θ siRNA attenuated the effect of TNFa on ABCA1, ABCG1, LXRa, SR-A, CD-36 expression. Our results suggest TNFa alter cholesterol metabolism in human macrophages through the inhibition of Reverse cholesterol transport and enhancing cholesterol uptake via PKC-θ-dependent pathway, implicating a potential mechanism of inflammation on atherogenic effects. Show less

Studies have shown that nifedipine protects against atherosclerotic progression, but its underlying mechanisms remain unclear. In this study, we examined if nifedipine increases macrophage cholesterol efflux, a pathway known to inhibit atherogenesis. We evaluated the ability of different doses of nifedipine to affect cholesterol efflux in RAW264.7 macrophages and its relationship with mRNA and protein levels of several well-characterized proteins involved in cholesterol efflux, including ABCA1, ABCG1, SR-BI and LXRα, using quantitative real-time PCR, Western blotting, and siRNA techniques. Nifedipne at 1, 10, and 100 nmol/L increased apoA-I-mediated cholesterol efflux from 2.55 % to 5.65 %, 6.20 %, and 6.10 %, as well as HDL-mediated cholesterol efflux from 31.0 % to 42.5 %, 46.0 %, and 43.5 %, respectively, in RAW264.7 macrophages (p < 0.05), which was associated with increased mRNA expression levels of ABCA1, ABCG1, SR-BI, and LXRα (405 %, 381 %, 336 %; 890 %, 960 %, 1002 %; 285 %, 325 %, 336 %; 482 %, 445 %, 405 %, respectively, p < 0.05), and with increased protein levels of ABCA1, ABCG1, SR-BI, and LXRα (428 %, 492 %, 361 %; 288 %, 331 %, 365 %; 283 %, 320 %, 505 %; 581 %, 678 %, 608 %, respectively, p < 0.05). SiRNA-mediated silencing of LXRα revealed that LXRα was involved in these increases and the enhanced cholesterol efflux. Nifedipine may protect against atherosclerosis partly by promoting macrophage cholesterol efflux through the stimulation of LXRα-dependent expression of ABCA1, ABCG1, and SR-BI. Show less

The expression changes of liver X receptor alpha (LXRα), histone deacetylase 3 (HDAC3) and CCAAT/enhancer binding protein alpha (C/EBPα) were detected in liver tissues of our high-fat-diet E3 rat model. The aim of this study is to pinpoint the molecular mechanism of HDAC3 and C/EBPα to orchestrate LXRα expression in hepatocytes. We confirmed that LXRα and its target genes were negatively regulated by HDAC3 in stable expressed clones with pEGFP-Hdac3 or shRNA-Hdac3 vector. However, transient pEGFP-C/EBPα plasmid transfection showed an upregulation of LXRα expression and C/EBPα enhanced LXRα promoter activity in a dose-dependent manner in CBRH-7919 cells. By using 5'-serial deletion reporter analysis, we identified that fragment from -2881 to -1181bp of LXRα promoter was responsible for C/EBPα binding to the promoter, especially CBS1 and CBS4 were identified essentially by using ChIP and luciferase reporter assay. Co-IP, qRT-PCR and ChIP revealed that HDAC3 interacted with C/EBPα co-regulated LXRα expression. Sumoylation of C/EBPα at lysine 159 was detected in CBRH-7919 cells with transient overexpressed C/EBPα, and Co-IP assay detected that sumoylated C/EBPα interacted with more HDAC3 than C/EBPα K159L mutant. Luciferase reporter assay demonstrated that C/EBPα participated in HDAC3-repressed LXRα transcription, and HDAC3 was involved in sumoylated C/EBPα-inactivated LXRα activity. Luciferase reporter assay demonstrated that sumoylation of C/EBPα by SUMO-1 directly reversed the activation of C/EBPα on LXRα promoter. The results suggested that HDAC3 interacts with sumoylated C/EBPα to negatively regulate the LXRα expression. Show less

Epidemiological studies demonstrate that the link between impaired fetal development and glucose intolerance in later life is exacerbated by postnatal catch-up growth. Maternal protein restriction (MPR) during pregnancy and lactation in the rat has been previously demonstrated to lead to impaired glucose tolerance in adulthood, however the effects of protein restoration during weaning on glucose homeostasis are largely unknown. Recent in vitro studies have identified that the liver X receptor α (LXRα) maintains glucose homeostasis by inhibiting critical genes involved in gluconeogenesis including G6pase (G6pc), 11β-Hsd1 (Hsd11b1) and Pepck (Pck1). Therefore, we hypothesized that MPR with postnatal catch-up growth would impair LXRα in vivo, which in turn would lead to augmented gluconeogenic LXRα-target gene expression and glucose intolerance. To examine this hypothesis, pregnant Wistar rats were fed a control (20%) protein diet (C) or a low (8%) protein diet during pregnancy and switched to a control diet at birth (LP). At 4 months, the LP offspring had impaired glucose tolerance. In addition, LP offspring had decreased LXRα expression, while hepatic expression of 11β-HSD1 and G6Pase was significantly higher. This was concomitant with decreased binding of LXRα to the putative LXRE on 11β-Hsd1 and G6pase. Finally, we demonstrated that the acetylation of histone H3 (K9,14) surrounding the transcriptional start site of hepatic Lxrα (Nr1h3) was decreased in LP offspring, suggesting MPR-induced epigenetic silencing of the Lxrα promoter. In summary, our study demonstrates for the first time the important role of LXRα in mediating enhanced hepatic gluconeogenic gene expression and consequent glucose intolerance in adult MPR offspring. Show less

Recent researches have implicated that mutations in the neurexin-3 (NRXN3) gene on chromosome 14q24.3-q31.1 might play a role in addiction, autism, and obesity. In order to explore the association of NRXN3 polymorphisms with schizophrenia, we examined seven single nucleotide polymorphisms (SNPs) in NRXN3 spanning 1.33 Mb of this gene, in a Chinese Han sample of 1214 schizophrenic patients and 1517 healthy control subjects. Our results showed that three SNPs were associated with schizophrenia (rs7157669: A>C, p=0.006; rs724373: C>T, p=0.014; rs7154021: C>T, p=0.018). After being corrected for multiple tests, the association of rs7157669 remained significant but those for two others were modest. According to the linkage disequilibrium pattern, the 7 SNPs may construct 3 haplotype blocks. Several haplotypes were significantly associated with schizophrenia, constructed by rs11624704-rs7157669-rs724373 (AAC, p=0.003; ACT, p=0.007, both remained significant after permutation tests), rs7154021-rs7142344 (TT, p=0.024; CT, p=0.012), respectively. Among the patients, 326 ones at first onset have received 6-week monotherapy of risperidone. Further analyses showed that two SNPs were associated with percentage of bodyweight gain following a 6-week therapy of risperidone (rs11624704: p=0.03; rs7154021: p=0.008) and rs7154021 remained significant after permutation test. Our findings suggested that NRXN3 might represent a major susceptibility gene for schizophrenia and have a role in bodyweight gain related to therapy of risperidone in Chinese Han population. Show less

Glucose-dependent insulinotropic peptide (GIP) exerts multiple biological effects via the G-protein-coupled receptor GIPR, including glucose-stimulated insulin production and secretion, cell proliferation, and antiapoptosis in pancreatic β-cells. In an obese state, the circulating level of GIP is elevated. GIPR-knockout mice are resistant to high-fat-diet-induced obesity. The rising evidence suggests a potential role of GIP in adipocyte biology and lipid metabolism. In our study, we overexpressed GIPR in 3T3-L1 CAR adipocytes and demonstrated that GIP impaired the physiological functions of adipocytes as a consequence of increased production of inflammatory cytokines and chemokines and phosphorylation of IkB kinase (IKK)-β through activation of the cAMP-PKA pathway. Activation of Jun N-terminal kinase (JNK) pathway was also observed during GIP-induced inflammatory responses in adipocytes. The inhibition of JNK blocked GIP-stimulated secretion of inflammatory cytokines and chemokines, as well as phosphorylation of IKKβ. In addition, GIP-induced inflammatory response increased basal glucose uptake but inhibited insulin-stimulated glucose uptake. Moreover, GIP-induced adipocyte inflammation impaired insulin signaling in adipocytes as demonstrated by a reduction of AKT phosphorylation. Our results suggest that GIP might be one of the stimuli attributable to obesity-induced insulin resistance via the induction of adipocyte inflammation. Show less

Apolipoprotein AIV (apo AIV) and cholecystokinin (CCK) are satiation factors secreted by the small intestine in response to lipid meals. Apo AIV and CCK-8 has an additive effect to suppress food intake relative to apo AIV or CCK-8 alone. In this study, we determined whether CCK-8 (1, 3, or 5 μg/kg ip) reduces food intake in fasted apo AIV knockout (KO) mice as effectively as in fasted wild-type (WT) mice. Food intake was monitored by the DietMax food system. Apo AIV KO mice had significantly reduced 30-min food intake following all doses of CCK-8, whereas WT mice had reduced food intake only at doses of 3 μg/kg and above. Post hoc analysis revealed that the reduction of 10-min and 30-min food intake elicited by each dose of CCK-8 was significantly larger in the apo AIV KO mice than in the WT mice. Peripheral CCK 1 receptor (CCK1R) gene expression (mRNA) in the duodenum and gallbladder of the fasted apo AIV KO mice was comparable to that in WT mice. In contrast, CCK1R mRNA in nodose ganglia of the apo AIV KO mice was upregulated relative to WT animals. Similarly, upregulated CCK1R gene expression was found in the brain stem of apo AIV KO mice by in situ hybridization. Although it is possible that the increased satiating potency of CCK in apo AIV KO mice is mediated by upregulation of CCK 1R in the nodose ganglia and nucleus tractus solitarius, additional experiments are required to confirm such a mechanism. Show less

Four hundred male chickens were selected to study the effects of pyruvate (Pyr), creatine pyruvate (CrPyr) and creatine (Cr) on the expression of hepatic mitochondrial and cytoplasm proteins associated with lipid and protein metabolism. Mitochondrial purification was accomplished using the two-step differential centrifugation and density gradient method, and the activities of organelle-specific marker enzymes were determined to assess the purity of the mitochondria. Proteins were extracted and fractionated by two-dimensional electrophoresis and the differential protein spots were assessed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. CrPyr reduced fatty acid accumulation by down-regulating adipose differentiation-related protein, inhibited ATP synthase expression, and reduced cholesteryl ester transfer protein (CETP) expression, thus reducing the levels of high density lipoprotein and triglycerol (TG) levels (thereby lowering fat and cholesterol deposition). CrPyr increased the expression of eukaryotic translation initiation factor (eIF) 2B, calreticulin (CRT) and eIF3a, thus promoting protein synthesis. CrPyr up-regulated the expression of fatty acid-binding proteins, CETP and apolipoprotein A-IV in cytoplasmic extracts, and these proteins accelerated the decomposition of fatty acids and TG, thus reducing fat deposition. In conclusion, CrPyr plays an important role in lipolysis and protein synthesis, and this effect was more pronounced than was the effect of Pyr and Cr. Show less

To further investigate the biological function of human novel gene CTRP4 by constructing the prokaryotic expression vector of human CTRP4, inducing the expression of and purifying hCTRP4-his protein in E.coli, and preparing polyclonal antibody against human CTRP4. Human CTRP4 gene was amplified by PCR, digested with enzymes, and subcloned into a his-tagged prokaryotic expression vector to generate a recombinant plasmid named pET-32a-hCTRP4. The pET-32a-hCTRP4 was transformed into E.coli BL21(DE3). The hCTRP4-his fusion protein was induced by IPTG, purified by Ni-NTA purification system, and analyzed by SDS-PAGE. The recombinant vector pcDNA3.1-myc/his(-)B-hCTRP4 expressing full-length human CTRP4 and purified prokaryotic protein hCTRP4 were used to immunize BALB/c mice to produce polyclonal antibody. The anti-serum was purified and the characteristics of the antibody were identified by ELISA, Western blotting, immunofluorescence cytochemistry and immunohistochemistry. The prokaryotic expression vector of pET-32a-hCTRP4 was constructed successfully. hCTRP4-his fusion protein was expressed in E.coli BL21(DE3) after IPTG induction. The titer of the anti-serum reached 1:20 000, and its specificity was proved by Western blotting. The results of immunofluorescence cytochemistry and immunohistochemistry indicated that CTRP4 was mainly localized in the cytoplasm of hepatic cells. hCTRP4-his fusion protein can be successfully expressed in E.coli. A specific polyclonal antibody against human CTRP4 has been successfully prepared. Show less

During normal development primordial germ cells (PGCs) derived from the epiblast are the precursors of spermatogonia and oogonia. In culture, PGCs can be induced to dedifferentiate to pluripotent embryonic germ (EG) cells in the presence of various growth factors. Several recent studies have now demonstrated that spermatogonial stem cells (SSCs) can also revert back to pluripotency as embryonic stem (ES)-like cells under certain culture conditions. However, the potential dedifferentiation of SSCs into PGCs or the potential generation of oocytes from SSCs has not been demonstrated before. We report that mouse male SSCs can be converted into oocyte-like cells in culture. These SSCs-derived oocytes (SSC-Oocs) were similar in size to normal mouse mature oocytes. They expressed oocyte-specific markers and gave rise to embryos through parthenogenesis. Interestingly, the Y- and X-linked testis-specific genes in these SSC-Oocs were significantly down-regulated or turned off, while oocyte-specific X-linked genes were activated. The gene expression profile appeared to switch to that of the oocyte across the X chromosome. Furthermore, these oocyte-like cells lost paternal imprinting but acquired maternal imprinting. Our data demonstrate that SSCs might maintain the potential to be reprogrammed into oocytes with corresponding epigenetic reversals. This study provides not only further evidence for the remarkable plasticity of SSCs but also a potential system for dissecting molecular and epigenetic regulations in germ cell fate determination and imprinting establishment during gametogenesis. Show less

A recent genome-wide association study in Caucasians revealed that three loci (rs174547 in fatty acid desaturase 1 (FADS1), rs2338104 near mevalonate kinase/methylmalonic aciduria, cobalamin deficiency, cblB type (MVK/MMAB) and rs10468017 near hepatic lipase (LIPC)) influence the plasma concentrations of high-density lipoprotein-cholesterol (HDL-C) and triglycerides (TG). However, there are few reports on the associations between these polymorphisms and plasma lipid concentrations in Chinese individuals. This study aimed to evaluate the associations between these three polymorphisms with HDL-C and TG concentrations, as well as coronary heart disease (CHD) susceptibility in Chinese individuals. We conducted a population-based case-control study in Chinese individuals to evaluate the associations between these three polymorphisms and HDL-C and TG concentrations, and also evaluated their associations with susceptibility to CHD. Genotypes were determined using polymerase chain reaction-restriction fragment length polymorphism assays and TaqMan genotyping assays. We found significant differences in TG and HDL-C concentrations among the TT, TC and CC genotypes of FADS1 rs174547 (P=0.017 and 0.003, respectively, multiple linear regression). The CC variant of rs174547 was significantly associated with hyperlipidemia compared with the TT variant (adjusted odds ratio (OR)=1.71, 95% confidence intervals (CI): 1.16-2.54). The FADS1 rs174547 CC variant was also associated with significantly increased CHD risk compared with the TT and TC variant (adjusted OR=1.53, 95%CI: 1.01-2.31), and the effect was more evident among nonsmokers and females. The polymorphisms rs2338104 and rs10468017 did not significantly influence HDL-C or TG concentrations in this Chinese population. rs174547 in FADS1 may contribute to the susceptibility of CHD by altering HDL-C and TG levels in Chinese individuals. Show less

Ezh2 is a histone trimethyltransferase that silences genes mainly via catalyzing trimethylation of histone 3 lysine 27 (H3K27Me3). The role of Ezh2 as a regulator of gene silencing and cell proliferation in cancer development has been extensively investigated; however, its function in heart development during embryonic cardiogenesis has not been well studied. In the present study, we used a genetically modified mouse system in which Ezh2 was specifically ablated in the mouse heart. We identified a wide spectrum of cardiovascular malformations in the Ezh2 mutant mice, which collectively led to perinatal death. In the Ezh2 mutant heart, the endocardial cushions (ECs) were hypoplastic and the endothelial-to-mesenchymal transition (EMT) process was impaired. The hearts of Ezh2 mutant mice also exhibited decreased cardiomyocyte proliferation and increased apoptosis. We further identified that the Hey2 gene, which is important for cardiomyocyte proliferation and cardiac morphogenesis, is a downstream target of Ezh2. The regulation of Hey2 expression by Ezh2 may be independent of Notch signaling activity. Our work defines an indispensible role of the chromatin remodeling factor Ezh2 in normal cardiovascular development. Show less

The present study was designed to search for potential diagnostic biomarkers in the serum of colorectal cancer (CRC). CRC is the third most common cancer worldwide, and its prognosis is poor at early stages. A panel of novel biomarkers is urgently needed for early diagnosis of CRC. An integrated proteomics and metabolomics approach was performed to define oncofetal biomarkers in CRC by protein and metabolite profiling of serum samples from CRC patients, healthy control adults, and fetus. The differentially expressed proteins were identified by a 2-D DIGE (2-Dimensional Difference Gel Electrophoresis) coupled with a Finnigan LTQ-based proteomics approach. Meanwhile, the serum metabolome was analyzed using gas chromatography-mass spectrometry integrated with a commercial mass spectral library for peak identification. Of the 28 identified proteins and the 34 analyzed metabolites, only 5 protein spots and 6 metabolites were significantly increased or decreased in both CRC and fetal serum groups compared with the healthy adult group. Data from supervised predictive models allowed a separation of 93.5% of CRC patients from the healthy controls using the 6 metabolites. Finally, correlation analysis was applied to establish quantitative linkages between the 5 individual metabolite 3-hydroxybutyric acid, L-valine, L-threonine, 1-deoxyglucose, and glycine and the 5 individual proteins MACF1, APOH, A2M, IGL@, and VDB. Furthermore, 10 potential oncofetal biomarkers were characterized and their potential for CRC diagnosis was validated. The integrated approach we developed will promote the translation of biomarkers with clinical value into routine clinical practice. Show less

The gradually increasing changes in a human hyperlipidemic diet along with chronic stress might play an important role in the increased numbers of fatty liver. This study investigated the effects of Ilex asprella root decoction on related genes of lipid metabolism in chronic stress in hyperlipidemic fatty liver in rats. Forty-eight male Wistar rats were randomly divided into four groups: normal control group, model control group, simvastatin group, and Ilex asprella root group. To establish chronic stress and hyperlipidemic fatty liver models in rats, the levels of serum lipids, glucose, liver index, insulin (INS), insulin resistant (IR) index, adiponectin, superoxide dismutase (SOD), glutathione peroxidase (GSH-pX), glutathione (GSH), liver X receptor (LXR), and sterol responsive element binding protein (SREBP)-1c in rats were measured. When compared to the normal control group, the levels of serum lipids, glucose, liver index, INS, IR index, and GSH in the model control group significantly increased (P < 0.01). The protein levels of LXRα and SREBP-1c increased (P < 0.05), and the serum adiponectin and the SOD and GSH-pX decreased significantly (P < 0.01). When compared to the model control group, the levels of serum lipids, glucose, liver index, INS, IR index, SOD, and GSH-pX in the simvastatin group and Ilex asprella root group increased in varying degrees (P < 0.01 or 0.05); the serum adiponectin and GSH decreased (P < 0.05), while the protein levels of LXRα and SREBP-1c decreased in varying degrees (P < 0.01 or 0.05). When compared to the simvastatin group, the IR index and protein levels of LXRα in the Ilex asprella root group decreased (P < 0.05), and the serum adiponectin and SOD increased (P < 0.05). The Ilex asprella root decoction has some protective effects on regulating the related genes of lipid metabolism caused by chronic stress and hyperlipidemic fatty liver in rats. Show less

Resveratrol (RSV), a naturally occurring polyphenolic stilbenoid, is known to possess potent anti-atherogenic properties; however, the effect of RSV on hypercholesterolemia is not fully understood. We hypothesized that RSV decreases blood cholesterol levels through the activation of cholesterol 7α-hydroxylase (CYP7A1)-mediated bile acid synthetic pathway pathways in vitro and in vivo. In this study, we evaluated body weight, serum lipid concentrations, hepatic lipid content and the size of the bile acid pool in high-fat diet (HFD)-fed C57BL/6 J mice that were treated with RSV. In addition, we characterized the underlying mechanism of the effects of RSV in HepG2 hepatocytes by Western blot analysis. RSV (200 mg/kg per day) reduced body weight and liver weight gains, improved serum lipid parameters, reduced hepatic cholesterol accumulation and increased the bile acid pool size in mice fed an HFD for 8 wks. RSV significantly increased liver expression of CYP7A1 mRNA and protein and CYP7A1 enzyme activity. Furthermore, RSV treatment upregulated CYP7A1 expression and induced liver X receptor alpha (LXRα) activation in a time- and dose-dependent manner in HepG2 cells. In addition, the specific liver X receptor alpha (LXRα) inhibitor geranylgeranyl pyrophosphate (GGPP) inhibited the RSV-induced expression of CYP7A1 in HepG2 hepatocytes. The beneficial effects of RSV on HFD-induced hypercholesterolemia are mediated through LXRα signaling pathways, suggesting a potential target for the prevention of dyslipidemia. Show less

Genetic variation may influence chemotherapy response and overall survival in cancer patients. We conducted a genome-wide scan in 535 advanced-stage non-small cell lung cancer (NSCLC) patients from two independent cohorts (307 from Nanjing and 228 from Beijing). A replication was carried out on an independent cohort of 340 patients from Southeastern China followed by a second validation on 409 patients from the Massachusetts General Hospital (Boston, MA). Consistent associations with NSCLC survival were identified for five single-nucleotide polymorphisms (SNP) in Chinese populations with P values ranging from 3.63 × 10(-5) to 4.19 × 10(-7) in the additive genetic model. The minor allele of three SNPs (rs7629386 at 3p22.1, rs969088 at 5p14.1, and rs3850370 at 14q24.3) were associated with worse NSCLC survival while 2 (rs41997 at 7q31.31 and rs12000445 at 9p21.3) were associated with better NSCLC survival. In addition, rs7629386 at 3p22.1 (CTNNB1) and rs3850370 at 14q24.3 (SNW1-ALKBH1-NRXN3) were further replicated in the Caucasian population. In this three-stage genome-wide association studies, we identified five SNPs as markers for survival of advanced-stage NSCLC patients treated with first-line platinum-based chemotherapy in Chinese Han populations. Two of these SNPs, rs7629386 and rs3850370, could also be markers for survival among Caucasian patients. Show less

Autism spectrum disorders (ASDs) are highly heritable, yet relatively few associated genetic loci have been replicated. Copy number variations (CNVs) have been implicated in autism; however, the majority of loci contribute to <1% of the disease population. Therefore, independent studies are important to refine associated CNV regions and discover novel susceptibility genes. In this study, a genome-wide SNP array was utilized for CNV detection by two distinct algorithms in a European ancestry case-control data set. We identify a significantly higher burden in the number and size of deletions, and disrupting more genes in ASD cases. Moreover, 18 deletions larger than 1 Mb were detected exclusively in cases, implicating novel regions at 2q22.1, 3p26.3, 4q12 and 14q23. Case-specific CNVs provided further evidence for pathways previously implicated in ASDs, revealing new candidate genes within the GABAergic signaling and neural development pathways. These include DBI, an allosteric binder of GABA receptors, GABARAPL1, the GABA receptor-associated protein, and SLC6A11, a postsynaptic GABA transporter. We also identified CNVs in COBL, deletions of which cause defects in neuronal cytoskeleton morphogenesis in model vertebrates, and DNER, a neuron-specific Notch ligand required for cerebellar development. Moreover, we found evidence of genetic overlap between ASDs and other neurodevelopmental and neuropsychiatric diseases. These genes include glutamate receptors (GRID1, GRIK2 and GRIK4), synaptic regulators (NRXN3, SLC6A8 and SYN3), transcription factor (ZNF804A) and RNA-binding protein FMR1. Taken together, these CNVs may be a few of the missing pieces of ASD heritability and lead to discovering novel etiological mechanisms. Show less

Autism spectrum disorders (ASD) represent a group of neurodevelopmental disorders characterized by a core set of social-communicative and behavioral impairments. Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the brain, acting primarily via the GABA receptors (GABR). Multiple lines of evidence, including altered GABA and GABA receptor expression in autistic patients, indicate that the GABAergic system may be involved in the etiology of autism. As copy number variations (CNVs), particularly rare and de novo CNVs, have now been implicated in ASD risk, we examined the GABA receptors and genes in related pathways for structural variation that may be associated with autism. We further extended our candidate gene set to include 19 genes and regions that had either been directly implicated in the autism literature or were directly related (via function or ancestry) to these primary candidates. For the high resolution CNV screen we employed custom-designed 244 k comparative genomic hybridization (CGH) arrays. Collectively, our probes spanned a total of 11 Mb of GABA-related and additional candidate regions with a density of approximately one probe every 200 nucleotides, allowing a theoretical resolution for detection of CNVs of approximately 1 kb or greater on average. One hundred and sixty-eight autism cases and 149 control individuals were screened for structural variants. Prioritized CNV events were confirmed using quantitative PCR, and confirmed loci were evaluated on an additional set of 170 cases and 170 control individuals that were not included in the original discovery set. Loci that remained interesting were subsequently screened via quantitative PCR on an additional set of 755 cases and 1,809 unaffected family members. Results include rare deletions in autistic individuals at JAKMIP1, NRXN1, Neuroligin4Y, OXTR, and ABAT. Common insertion/deletion polymorphisms were detected at several loci, including GABBR2 and NRXN3. Overall, statistically significant enrichment in affected vs. unaffected individuals was observed for NRXN1 deletions. These results provide additional support for the role of rare structural variation in ASD. Show less

Diseases related to smoking are the second leading cause of death in the world. Cigarette smoking is a risk factor for several diseases such as cancer and cardiovascular and respiratory disorders. Despite increasing evidence of genetic determination, the susceptibility genes and loci underlying various aspects of smoking behavior are largely unknown. Moreover, almost all reported genome-wide association studies (GWASs) have been performed on samples of European origin, limiting the applicability of the results to other ethnic populations. In this first GWAS on smoking behavior in an Asian population, after analyzing 8,842 DNA samples from the Korea Association Resource project with 352,228 single nucleotide polymorphisms (SNPs) genotyped for each sample, we identified 8 SNPs significantly associated with smoking initiation (SI) and 4 with nicotine dependence (ND). Because of the current unavailability of an independent Asian smoking sample, we replicated the discoveries in independent samples of European-American and African-American origin. Of the 12 SNPs examined in the replicated samples, we identified two SNPs, in the regulator of G-protein signaling 17 gene (rs7747583, p value(meta) = 6.40 × 10(-6); rs2349433, p value(meta) = 5.57 × 10(-6)), associated with SI. Also, we found two SNPs significantly associated with ND; one in the FERM domain containing 4A (rs4424567, p value(meta) = 2.30 × 10(-6)) and the other at 7q31.1 (rs848353, p value(meta) = 9.16 × 10(-8)). These SNPs represent novel targets for examination of smoking behavior and warrant further investigation using independent samples. Show less

To explore the distribution characteristics of apolipoprotein A5 (ApoA5) gene c.553G > T polymorphism and the relationship of serum lipid in Chinese Han and Uighur populations in Xinjiang, China. The genotypes of ApoA5 gene c.553G > T polymorphism were detected in 406 Uighur and 527 Han people by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). The frequencies of GG, GT and TT genotypes of ApoA5 gene c.553G > T were 378 (93.1%), 27 (6.7%) and 1 (0.25%) patients in Uighurs versus 478 (90.7%) patients, 49 (9.3%) patients and 0% in Hans. There was no significant difference in the distribution of genotypes between two groups (P > 0.05). In both groups, individuals with T allele (TT + GT genotype) had a higher level of serum triglyceride than those with GG genotype. After adjusting for gender, age, smoking, alcoholism, body mass index, blood pressure and blood lipid, non-conditional logistic regression analyses revealed that individuals with T allele (TT + GT genotype) in both groups had an elevated risk of HTG versus the GG genotype (OR = 3.31, 95%CI: 1.31 - 8.36 in Uighurs vs OR = 3.98, 95%CI: 1.81 - 8.74 in Hans). The mutation of c.553G > T polymorphism of ApoA5 gene is associated with the level of serum triglyceride in Uighur and Han populations of Xinjiang. And T allele may be a risk factor of hypertriglyceridemia. Show less

The aim is to investigate the association between coronary heart disease (CHD) and c.553G>T polymorphism of apolipoprotein A5 (ApoA5) gene and the influence of serum lipid level in the Han ethnic population of Xinjiang. The polymorphism of ApoA5 gene in 486 patients with CHD and 501 controls was analyzed by methods of polymerase chain reaction and restriction fragment length polymorphism analysis. Level of serum lipid in each patient was detected at the same time. There was significant difference in the distribution of genotypes between CHD group and controls group (χ(2)=8.757, P=0.013). Non-conditioned logistic regression analyses, after adjusted for age, gender, smoking, total serum cholesterol, presence of hypertension and diabetes, revealed that individuals who carried T allele (TT + GT genotype) had an increased risk of CHD, compared to GG genotype (OR=1.753, 95%CI: 1.030-2.983, P<0.05). There was also a remarkable difference noticed in the level of serum triglyceride by genotypes in CHD group and control group (t=-5.242, P<0.01; t=-3.499, P=0.001). Individuals in the two groups who carried T allele had higher level of serum triglyceride than those carried GG genotype. Individuals in CHD group who carried T allele had higher level of serum total cholesterol than those carried GG genotype (t=-2.465, P=0.014). It seemed that the c.553G>T polymorphism of ApoA5 gene had influenced on the level of serum triglyceride and the total cholesterol among Han population in Xinjiang. c.553G>T polymorphism was associated with the development of CHD, while T allele might be an influencing risk factor on CHD. Show less

To investigate the association of the -12238T/C polymorphism of apolipoprotein A5 (APOA5) gene with coronary heart disease (CHD) and the influence of serum lipid levels in Chinese Uygur population of Xinjiang. The -12238T/C polymorphism of APOA5 gene in 344 patients with CHD and 408 controls was analyzed by polymerase chain reaction-restriction fragment length polymorphism; the serum lipid levels were detected as well. The frequencies of CC, TC and TT genotype were 6.69%, 43.31% and 50.00% in the CHD group, while they were 14.95%, 45.10% and 39.95% in the control group. There was significant difference in the distribution of genotypes between the two groups (P < 0.01). Logistic regression analyses adjusted for age, gender, smoking, serum total cholesterol, presence of hypertension and diabetes revealed that individuals carrying CC genotype had an increased risk of CHD compared with TT genotype (OR = 0.328, 95%CI: 0.154-0.700). There was also significant difference in serum triglyceride level in genotypes between these two groups (P < 0.01). Patients in CHD group who carried CC and TC genotypes had lower serum triglyceride level than the TT genotype carriers. The -12238T/C polymorphism of APOA5 gene has influence on the serum triglyceride level in Uygur population of Xinjianxg. This polymorphism might be associated with development of CHD, and the CC genotype might be a protective factor in the development of CHD. Show less