Genome-wide association studies have identified over 150 loci associated with lipid traits, however, no large-scale studies exist for Hispanics and other minority populations. Additionally, the geneti Show more
Genome-wide association studies have identified over 150 loci associated with lipid traits, however, no large-scale studies exist for Hispanics and other minority populations. Additionally, the genetic architecture of lipid-influencing loci remains largely unknown. We performed one of the most racially/ethnically diverse fine-mapping genetic studies of HDL-C, LDL-C, and triglycerides to-date using SNPs on the MetaboChip array on 54,119 individuals: 21,304 African Americans, 19,829 Hispanic Americans, 12,456 Asians, and 530 American Indians. The majority of signals found in these groups generalize to European Americans. While we uncovered signals unique to racial/ethnic populations, we also observed systematically consistent lipid associations across these groups. In African Americans, we identified three novel signals associated with HDL-C (LPL, APOA5, LCAT) and two associated with LDL-C (ABCG8, DHODH). In addition, using this population, we refined the location for 16 out of the 58 known MetaboChip lipid loci. These results can guide tailored screening efforts, reveal population-specific responses to lipid-lowering medications, and aid in the development of new targeted drug therapies. Show less
Apolipoprotein A5 (apoA5) is a key regulator of triglyceride (TG) metabolism. This study is to investigate the role of apoA5 in obesity-associated hypertriglyceridemia and metformin-related hypotrigly Show more
Apolipoprotein A5 (apoA5) is a key regulator of triglyceride (TG) metabolism. This study is to investigate the role of apoA5 in obesity-associated hypertriglyceridemia and metformin-related hypotriglyceridemic actions. Two obese mouse models, including high-fat diet-induced obese mice and ob/ob obese mice, were adopted. The effects of low- and high-dose metformin were determined on plasma and hepatic TG and apoA5 of these obese mice. Besides, the effects of metformin on TG and apoA5 were also detected in mouse and human hepatocytes in vitro. (1) Plasma apoA5 levels in the obese mice were markedly elevated and positively correlated with TG. Hepatic TG contents and apoA5 expressions were also remarkably increased in the obese mice. (2) Metformin dose-dependently decreased hepatic and plasma TG and apoA5 in the obese mice. Similarly, metformin dose-dependently reduced cellular TG contents and apoA5 expressions in hepatocytes in vitro. Compared to APOA5 knock-down (KD), metformin plus APOA5 KD resulted in more TG reduction of hepatocytes. Increased hepatic and plasma apoA5 could be a result of obesity-associated hypertriglyceridemia, and metformin displays hypotriglyceridemic effects on obese mice partly via the apoA5 pathway. Show less
Polymorphisms in the apolipoprotein C-III (APOC3) gene have been reported to be associated with coronary heart disease (CHD), but the data so far have been conflicting. To derive a more precise estima Show more
Polymorphisms in the apolipoprotein C-III (APOC3) gene have been reported to be associated with coronary heart disease (CHD), but the data so far have been conflicting. To derive a more precise estimation of these associations, we performed a meta-analysis to investigate the three main polymorphisms (SstI, T-455C, C-482T) of APOC3 in all published studies. Databases including PubMed, Web of Science, Wanfang, SinoMed and CNKI were systematically searched. The association was assessed using odds ratios (ORs) with 95% confidence intervals (CIs). The statistical analysis was performed using Review Manager 5.3.3 and Stata 12.0. A total of 31 studies have been identified. The pooled odds ratio (OR) for the association between the APOC3 gene polymorphisms and CHD and its corresponding 95% confidence interval (95% CI) were evaluated by random or fixed effect models. A statistical association between APOC3 SstI polymorphism and CHD susceptibility was observed under an allelic contrast model (P= 0.003, OR = 1.14, 95% CI = 1.05-1.24), dominant genetic model (P= 0.01, OR = 1.14, 95% CI = 1.03-1.26), and recessive genetic model (P= 0.02, OR = 1.35, 95% CI = 1.06-1.71), respectively. A significant association between the APOC3 T-455C polymorphism and CHD was also detected under an allelic contrast (P < 0.0001, OR = 1.19, 95% CI = 1.10-1.29), dominant genetic model (P= 0.0003, OR = 1.24, 95% CI = 1.11-1.39) and recessive genetic model (P= 0.04, OR = 1.30, 95% CI = 1.01-1.67). No significant association between the APOC3 C-482T polymorphism and CHD was found under an allelic model (P= 0.94, OR = 1.00, 95% CI = 0.93-1.08), dominant genetic model (P= 0.20, OR = 1.07, 95% CI = 0.97-1.18) or recessive genetic model (P= 0.13, OR = 0.90, 95% CI = 0.79-1.03). This meta-analysis revealed that the APOC3 SstI and T-455C polymorphisms significantly increase CHD susceptibility. No significant association was observed between the APOC3 C-482T polymorphism and CHD susceptibility. Show less
We performed genome-wide meta-analysis of lipid traits on three samples of Mexican and Mexican American ancestry comprising 4,383 individuals, and followed up significant and highly suggestive associa Show more
We performed genome-wide meta-analysis of lipid traits on three samples of Mexican and Mexican American ancestry comprising 4,383 individuals, and followed up significant and highly suggestive associations in three additional Hispanic samples comprising 7,876 individuals. Genome-wide significant signals were observed in or near CELSR2, ZNF259/APOA5, KANK2/DOCK6 and NCAN/MAU2 for total cholesterol, LPL, ABCA1, ZNF259/APOA5, LIPC and CETP for HDL cholesterol, CELSR2, APOB and NCAN/MAU2 for LDL cholesterol, and GCKR, TRIB1, ZNF259/APOA5 and NCAN/MAU2 for triglycerides. Linkage disequilibrium and conditional analyses indicate that signals observed at ABCA1 and LIPC for HDL cholesterol and NCAN/MAU2 for triglycerides are independent of previously reported lead SNP associations. Analyses of lead SNPs from the European Global Lipids Genetics Consortium (GLGC) dataset in our Hispanic samples show remarkable concordance of direction of effects as well as strong correlation in effect sizes. A meta-analysis of the European GLGC and our Hispanic datasets identified five novel regions reaching genome-wide significance: two for total cholesterol (FN1 and SAMM50), two for HDL cholesterol (LOC100996634 and COPB1) and one for LDL cholesterol (LINC00324/CTC1/PFAS). The top meta-analysis signals were found to be enriched for SNPs associated with gene expression in a tissue-specific fashion, suggesting an enrichment of tissue-specific function in lipid-associated loci. Show less
Aberrant activation of Wnt/β-catenin signaling plays a key role in the onset and development of hepatocellular carcinomas (HCC), with about half of them acquiring mutations in either CTNNB1 or AXIN1. Show more
Aberrant activation of Wnt/β-catenin signaling plays a key role in the onset and development of hepatocellular carcinomas (HCC), with about half of them acquiring mutations in either CTNNB1 or AXIN1. However, it remains unclear whether these mutations impose sufficient β-catenin signaling or require upstream Wnt ligand activation for sustaining optimal growth, as previously suggested for colorectal cancers. Using a panel of nine HCC cell lines, we show that siRNA-mediated knockdown of β-catenin impairs growth of all these lines. Blocking Wnt secretion, by either treatment with the IWP12 porcupine inhibitor or knockdown of WLS, reduces growth of most of the lines. Unexpectedly, interfering with Wnt secretion does not clearly affect the level of β-catenin signaling in the majority of lines, suggesting that other mechanisms underlie the growth-suppressive effect. However, IWP12 treatment did not induce autophagy or endoplasmic reticulum (ER) stress, which may have resulted from the accumulation of Wnt ligands within the ER. Similar results were observed for colorectal cancer cell lines used for comparison in various assays. These results suggest that most colorectal and liver cancers with mutations in components of the β-catenin degradation complex do not strongly rely on extracellular Wnt ligand exposure to support optimal growth. In addition, our results also suggest that blocking Wnt secretion may aid in tumor suppression through alternative routes currently unappreciated. Show less
Previously identified common variants explain only a small fraction of the trait heritability and at most loci the identities of the underlying causal genes and their functional variants still remain Show more
Previously identified common variants explain only a small fraction of the trait heritability and at most loci the identities of the underlying causal genes and their functional variants still remain unknown. To identify the low-frequency and rare coding variants that influence lipid levels, we conducted a meta-analysis of exome-wide association studies in 14,473 Chinese subjects, followed by a joint analysis with 1000 genomes imputed data from 6,534 samples. We replicated 24 previously reported lipid loci with exome-wide significance (P < 3.3 × 10 Show less
Objective Several genetic variants have been found to increase the risk of restless legs syndrome (RLS). The aim of the present study was to determine if these genetic variants were also associated wi Show more
Objective Several genetic variants have been found to increase the risk of restless legs syndrome (RLS). The aim of the present study was to determine if these genetic variants were also associated with the comorbidity of RLS and migraine in patients. Methods Thirteen single-nucleotide polymorphisms (SNPs) at six RLS risk loci ( MEIS1, BTBD9, MAP2K5, PTPRD, TOX3, and an intergenic region on chromosome 2p14) were genotyped in 211 migraine patients with RLS and 781 migraine patients without RLS. Association analyses were performed for the overall cohort, as well as for the subgroups of patients who experienced migraines with and without aura and episodic migraines (EMs) vs. chronic migraines (CMs). In order to verify which genetic markers were potentially related to the incidence of RLS in migraine patients, multivariate regression analyses were also performed. Results Among the six tested loci, only MEIS1 was significantly associated with RLS. The most significant SNP of MEIS1, rs2300478, increased the risk of RLS by 1.42-fold in the overall cohort ( p = 0.0047). In the subgroup analyses, MEIS1 augmented the risk of RLS only in the patients who experienced EMs (odds ratio (OR) = 1.99, p = 0.0004) and not those experiencing CMs. Multivariate regression analyses further showed that rs2300478 in MEIS1 (OR = 1.39, p = 0.018), a CM diagnosis (OR = 1.52, p = 0.022), and depression (OR = 1.86, p = 0.005) were independent predictors of RLS in migraine. Conclusions MEIS1 variants were associated with an increased risk of RLS in migraine patients. It is possible that an imbalance in iron homeostasis and the dopaminergic system may represent a link between RLS incidence and migraines. Show less
Autophagy is a dynamic and self-limiting process. The amplitude and duration of this process need to be properly controlled to maintain cell homeostasis, and excessive or insufficient autophagy activi Show more
Autophagy is a dynamic and self-limiting process. The amplitude and duration of this process need to be properly controlled to maintain cell homeostasis, and excessive or insufficient autophagy activity could each lead to disease states. Compared to our understanding of the molecular mechanisms of autophagy induction, little is known about how the autophagy process is turned off after its activation. We recently identified KLHL20 as a key regulator of autophagy termination. By functioning as a substrate-binding subunit of CUL3 ubiquitin ligase, KLHL20 targets the activated ULK1 and phagophore-residing PIK3C3/VPS34 and BECN1 for ubiquitination and proteasomal degradation, which in turn triggers a destabilization of their complex components ATG13 and ATG14. These hierarchical degradation events cause the exhaustion of the autophagic pool of ULK1 and PIK3C3/VPS34 complexes, thereby preventing persistent and excessive autophagy activity. Impairment of KLHL20-dependent feedback regulation of autophagy enhances cell death under prolonged starvation and aggravates muscle atrophy in diabetic mice, which highlights the pathophysiological significance of this autophagy termination mechanism in cell survival and tissue homeostasis. Modulation of this autophagy termination pathway may be effective for treating diseases associated with deregulation of autophagy activity. Show less
The fatty acid desaturase (FADS) controls polyunsaturated fatty acid (PUFA) synthesis in human tissues and breast milk. Evaluate the influence of 10 single nucleotide polymorphisms (SNPs) and various Show more
The fatty acid desaturase (FADS) controls polyunsaturated fatty acid (PUFA) synthesis in human tissues and breast milk. Evaluate the influence of 10 single nucleotide polymorphisms (SNPs) and various haplotypes in the FADS gene cluster (FADS1, FADS2, FADS3) on PUFA concentration in the breast milk of 209 healthy Chinese women. PUFA concentrations were measured in breast milk using gas chromatography and genotyping was performed using the Sequenom Mass Array system. A SNP (rs1535) and 2-locus haplotypes (rs3834458-rs1535, rs1535-rs174575) in the FADS2 gene were associated with concentrations of γ-linoleic acid (GLA) and arachidonic acid (AA) in breast milk. Likewise, in the FADS1 gene, a 2-locus constructed haplotype (rs174547-rs174553) also affected GLA and AA concentration (P<0.05 for all). Minor allele carriers of the SNP and haplotypes described above had lower concentrations of GLA and AA. In the FADS2 gene, the 3-locus haplotype rs3834458-rs1535-rs174575, significantly affected concentrations of GLA but not AA. Pairwise comparison showed that individuals major homozygous for the SNP rs1000778 in the FADS3 gene had lower concentrations of ALA and linoleic acid (LA) in their breast milk. Polymorphisms in the FADS gene cluster influence PUFA concentrations in the breast milk of Chinese Han lactating women. Show less
The reductive 17β-hydroxysteroid dehydrogenases which catalyze the last step in estrogen activation for estrogen dependent breast cancer cells were studied. Their biological function and the effects o Show more
The reductive 17β-hydroxysteroid dehydrogenases which catalyze the last step in estrogen activation for estrogen dependent breast cancer cells were studied. Their biological function and the effects of their knockdown for cancer cell proliferation were demonstrated. The multidisciplinary study involves enzyme catalysis, sex-hormone and cell cycle regulation, as well as cell proliferation in breast cancer cells. Reductive 17β-HSD1, -7 and -12 were studied in the main breast cancer epithelial cells MCF-7 and T47D. Modification of estradiol and 5α-dihydrotestosterone concentrations was monitored by ELISA assay while corresponding cell viability measured by MTT assay. Cell cycle was determined by flow cytometry. Dual activity of estradiol activation and 5α-dihydrotestosterone reduction by 17β-HSD1 and -7 was critical for breast cancer cell (T47D and MCF-7) viability. Cell viability was decreased by 35.8% ± 1.6% in T47D cells after simultaneously knocking down 17β-HSD1 and -7. MCF-7 cell viability was decreased by 29.3% ± 4.2% using a combination of siRNAs and inhibitors. By knocking down 17β-HSD7, we have provided the first demonstration of the significant role of this enzyme in the stimulation of breast cancer cell viability as a result of its high activity on androgen reduction with positive feedback on estradiol production. A further decrease in cell viability was not observed with additional knockdown of 17β-HSD12 after 17β-HSD1 and 7. Breast cancer cell cycle progression was impeded to enter the S phase from G0-G1 after knocking down 17β-HSD1 and -7. In summary, this is the first demonstration that the dual activity in estrone activation and 5α-dihydrotestosterone reduction are the functional basis of reductive 17β-HSDs in breast cancer cells. 17β-HSD1 and -7 are principal reductive 17β-HSDs and major players in the viability of estrogen-dependent breast cancer cells. Combined targeting of these enzymes may be potential for molecular therapy of such cancer. Show less
Obesity is linked to type 2 diabetes (T2D) and cardiovascular diseases; however, the underlying molecular mechanisms remain unclear. We aimed to identify obesity-associated molecular features that may Show more
Obesity is linked to type 2 diabetes (T2D) and cardiovascular diseases; however, the underlying molecular mechanisms remain unclear. We aimed to identify obesity-associated molecular features that may contribute to obesity-related diseases. Using circulating monocytes from 1,264 Multi-Ethnic Study of Atherosclerosis (MESA) participants, we quantified the transcriptome and epigenome. We discovered that alterations in a network of coexpressed cholesterol metabolism genes are a signature feature of obesity and inflammatory stress. This network included 11 BMI-associated genes related to sterol uptake (↑LDLR, ↓MYLIP), synthesis (↑SCD, FADS1, HMGCS1, FDFT1, SQLE, CYP51A1, SC4MOL), and efflux (↓ABCA1, ABCG1), producing a molecular profile expected to increase intracellular cholesterol. Importantly, these alterations were associated with T2D and coronary artery calcium (CAC), independent from cardiometabolic factors, including serum lipid profiles. This network mediated the associations between obesity and T2D/CAC. Several genes in the network harbored C-phosphorus-G dinucleotides (e.g., ABCG1/cg06500161), which overlapped Encyclopedia of DNA Elements (ENCODE)-annotated regulatory regions and had methylation profiles that mediated the associations between BMI/inflammation and expression of their cognate genes. Taken together with several lines of previous experimental evidence, these data suggest that alterations of the cholesterol metabolism gene network represent a molecular link between obesity/inflammation and T2D/CAC. Show less
Trichorhinophalangeal syndrome type II (TRPS II, OMIM # 150230) is a rare autosomal dominant genetic disorder characterized by craniofacial and skeletal abnormalities. Loss of functional copies of the Show more
Trichorhinophalangeal syndrome type II (TRPS II, OMIM # 150230) is a rare autosomal dominant genetic disorder characterized by craniofacial and skeletal abnormalities. Loss of functional copies of the TRPS1 gene at 8q23.3 and the EXT1 gene at 8q24.11 are considered to be responsible for the syndrome. Herewith, we report an 8-year-old girl with sparse scalp hair, bulbous nose, thin upper lip, broad eyebrows, phalangeal abnormalities of both hands/toes, multiple exostoses, mild intellectual impairment and severe malnutrition. In addition, the patient also had annular pancreas, a rare co-existing feature in patients with TRPS II. A contiguous 5.47 Mb deletion involving 8q23.3-q24.12 was detected by array comparative genomic hybridization (aCGH), leading to haploinsufficiency of 10 protein coding genes, 1 long non-coding RNA and 1 microRNA. Quantitative PCR (qPCR) examination confirmed half-reduced DNA copy of the patient and normal expression of both parents, indicating a de novo origin of the deletion and complete penetrance of the mutation. Show less
Glucose is an essential nutrient that directly regulates the expression of numerous genes in liver and adipose tissue. The carbohydrate response element-binding protein (ChREBP) links glucose as a sig Show more
Glucose is an essential nutrient that directly regulates the expression of numerous genes in liver and adipose tissue. The carbohydrate response element-binding protein (ChREBP) links glucose as a signaling molecule to multiple glucose-dependent transcriptional regulatory pathways, particularly genes involved in glycolytic and lipogenic processes. In this study, we used chromatin immunoprecipitation followed by next-generation sequencing to identify specific ChREBP binding targets in liver and white adipose tissue. We found a large number of ChREBP binding sites, which are attributable to 5825 genes in the liver, 2418 genes in white adipose tissue, and 5919 genes in both tissues. The majority of these target genes were involved in known metabolic processes. Pathways in insulin signaling, the adherens junction, and cancers were among the top 5 pathways in both tissues. Motif analysis revealed a consensus sequence CAYGYGnnnnnCRCRTG that was commonly shared by ChREBP binding sites. Putative ChREBP binding sequences were enriched on promoters of genes involved in insulin signaling pathway, insulin resistance, and tumorigenesis. Show less
Platelets are believed to be critical in pulmonary-origin ARDS as mediators of endothelial damage through their interactions with fibrinogen and multiple signal transduction pathways. A prior meta-ana Show more
Platelets are believed to be critical in pulmonary-origin ARDS as mediators of endothelial damage through their interactions with fibrinogen and multiple signal transduction pathways. A prior meta-analysis identified five loci for platelet count (PLT): BAD, LRRC16A, CD36, JMJD1C, and SLMO2. This study aims to validate the quantitative trait loci (QTLs) of PLT within BAD, LRRC16A, CD36, JMJD1C, and SLMO2 among critically ill patients and to investigate the associations of these QTLs with ARDS risk that may be mediated through PLT. ARDS cases and at-risk control subjects were recruited from the intensive care unit of the Massachusetts General Hospital. Exome-wide genotyping data of 629 ARDS cases and 1,026 at-risk control subjects and genome-wide gene expression profiles of 18 at-risk control subjects were generated for analysis. Single-nucleotide polymorphism (SNP) rs7766874 within LRRC16A was a significant locus for PLT among at-risk control subjects (β = -13.00; 95% CI, -23.22 to -2.77; P = .013). This association was validated using LRRC16A gene expression data from at-risk control subjects (β = 77.03 per 1 SD increase of log2-transformed expression; 95% CI, 27.26-126.80; P = .005). Further, rs7766874 was associated with ARDS risk conditioned on PLT (OR = 0.68; 95% CI, 0.51-0.90; P = .007), interacting with PLT (OR = 1.15 per effect allele per 100 × 103/μL of PLT; 95% CI, 1.03-1.30; P = .015), and mediated through PLT (indirect OR = 1.045; 95% CI, 1.007-1.085; P = .021). Our findings support the role of LRRC16A in platelet formation and suggest the importance of LRRC16A in ARDS pathophysiology by interacting with, and being mediated through, platelets. Show less
Existing evidence suggests that adverse pregnancy outcomes are closely related with dietary factors. Previous studies in mice have focused on the harm of folate deficiency (FD) on development of embry Show more
Existing evidence suggests that adverse pregnancy outcomes are closely related with dietary factors. Previous studies in mice have focused on the harm of folate deficiency (FD) on development of embryo, while the effect of low maternal folate levels on maternal intrauterine environment during early pregnancy remains unclear. Since our previous study found that FD treatment of mice causes no apparent defects in embryo implantation but is accompanied by female subfertility, we next chose to investigate a potential role of FD on molecular events after implantation. We observed that the decidual bulges began to be stunted on pregnancy day 6. The results of functional experiments in vivo and in vitro showed that FD inhibited the process of endometrial decidualization. It has been confirmed that DNA methylation participates in decidualization, and folate as a methyl donor could change the methylation patterns of genes. Thus, we hypothesized that FD impairs maternal endometrial decidualization by altering the methylation profiles of related genes. Reduced representation bisulphite sequencing was carried out to detect the methylation profiles of endometrium on pregnancy day 6-8, which is equivalent to the decidualization period in mice. The results confirmed that FD changes the methylation patterns of genome, and GO analysis of the differentially methylated regions revealed that the associated genes mainly participate in biological adhesion, biological regulation, cell proliferation, development, metabolism and signalling. In addition, we found some candidates for regulators of decidual transformation, such as Nr1h3 and Nr5a1. The data indicate that FD inhibits decidualization, possibly by altering methylation patterns of the genome in mice. Show less
Polyunsaturated fatty acid (PUFA) status has been associated with neuropsychiatric disorders, including depression and risk of suicide. Long-chain PUFAs (LC-PUFAs) are obtained in the diet or produced Show more
Polyunsaturated fatty acid (PUFA) status has been associated with neuropsychiatric disorders, including depression and risk of suicide. Long-chain PUFAs (LC-PUFAs) are obtained in the diet or produced by sequential desaturation and elongation of shorter-chain precursor fatty acids linoleic acid (LA, 18:2n-6) and α-linolenic acid (ALA, 18:3n-3). We compared DNA methylation patterns in genes involved in LC-PUFA biosynthesis in major depressive disorder (MDD) with (n = 22) and without (n = 39) history of suicide attempt, and age- and sex-matched healthy volunteers (n = 59). Plasma levels of selected PUFAs along the LC-PUFA biosynthesis pathway were determined by transesterification and gas chromatography. CpG methylation levels for the main human LC-PUFA biosynthetic genes, fatty acid desaturases 1 (Fads1) and 2 (Fads2), and elongation of very long-chain fatty acids protein 5 (Elovl5), were assayed by bisulfite pyrosequencing. Associations between PUFA levels and diagnosis or suicide attempt status did not survive correction for multiple testing. However, MDD diagnosis and suicide attempts were significantly associated with DNA methylation in Elovl5 gene regulatory regions. Also the relative roles of PUFA levels and DNA methylation with respect to diagnostic and suicide attempt status were determined by least absolute shrinkage and selection operator logistic regression analyses. We found that PUFA associations with suicide attempt status were explained by effects of Elovl5 DNA methylation within the regulatory regions. The observed link between plasma PUFA levels, DNA methylation, and suicide risk may have implications for modulation of disease-associated epigenetic marks by nutritional intervention. Show less
Steatotic liver grafts, although accepted, increase the risk of poor posttransplantation liver function. However, the growing demand for adequate donor organs has led to the increased use of so-called Show more
Steatotic liver grafts, although accepted, increase the risk of poor posttransplantation liver function. However, the growing demand for adequate donor organs has led to the increased use of so-called marginal grafts. Liver X receptor alpha (LXRalpha) is important in fatty acid metabolism and interrelated with the specific ischemia-reperfusion injury in fatty liver transplantation. This study aimed to investigate whether LXRalpha RNA interference (RNAi) could improve the organ function of liver transplant recipients. Fifty Sprague-Dawley rats were fed with a high-fat diet and 56% alcohol. The livers of these animals had greater than 60% macrovesicular steatosis and were used as liver donors. The experimental donors were treated with 7X107 TU LXRalpha-RNAi-LV of a mixture injection and control donors with negative control-LV vector injection into the portal vein 72 hours before the operation. The effects of LXRalpha-RNAi-LV were assessed by serum aminotransferases, histology, immunostaining, and protein levels. The transcription of LXRalpha mRNA was assessed by reverse transcription-polymerase chain reaction. Compared with controls, LXRalpha RNAi inhibited the expression of LXRalpha at the mRNA (0.53+/-0.03 vs 0.94+/-0.02, P<0.05) and protein levels (0.51+/-0.08 vs 1.09+/-0.12, P<0.05). LXRalpha RNAi also decreased the expressions of sterol regulatory element-binding protein 1c (SREBP-1c) and CD36. LXRalpha RNAi consequently reduced fatty acid accumulation in hepatocytes. Compared with control animals, LXRalpha RNAi-treated group had lower serum alanine aminotransferase, aspartate aminotransferase, interleukin-1beta, and tumor necrosis factor-alpha levels and milder pathologic damages. TUNEL analysis revealed a significant reduction of apoptosis in the livers of rats treated with LXRalpha-RNAi-LV, and overall survival as determined by the Kaplan-Meier method was improved among rats treated with LXRalpha-RNAi-LV (P<0.05). LXRalpha-RNAi-LV treatment significantly downregulated LXRalpha expression and improve steatotic liver graft function and recipient survival after a fatty liver transplantation in rats. Show less
The aim of this research was to present prenatal diagnosis of Langer-Giedion syndrome (LGS/TRPS type II) and Cornelia de Lange syndrome-4 (CDLS4). A 36-year-old woman underwent amniocentesis at 17 wee Show more
The aim of this research was to present prenatal diagnosis of Langer-Giedion syndrome (LGS/TRPS type II) and Cornelia de Lange syndrome-4 (CDLS4). A 36-year-old woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Conventional cytogenetic analysis of amniocentesis revealed an interstitial deletion of chromosome 8q or del(8)(q23.3q24.13). Level II prenatal ultrasound examination revealed craniofacial dysmorphism. The pregnancy was terminated, and a malformed fetus was delivered with characteristic craniofacial dysmorphism of LGS/TRPS type II and CDLS4. Whole-genome array comparative genomic hybridization (aCGH) on the DNA extracted from cultured amniocytes was performed. The analysis by aCGH revealed a result of arr 8q23.3q24.11 (116,087,006-118,969,399)×1, 8q24.13 (123,086,851-124,470,847)×1 (NCBI build 37) with a 2.88-Mb deletion of 8q23.3-q24.11 encompassing six OMIM genes, TRPS1, EIF3H, RAD21, SLC30A8, MED30, and EXT1, and a 1.383-Mb deletion of 8q24.13 encompassing four OMIM genes, ZHX2, DERL1, ZHX1, and ATAD2. In the present case, the conventional cytogenetic analysis of cultured amniocytes revealed del(8)(q23.3q24.13), whereas aCGH analysis of cultured amniocytes showed the deletions of 8q23.3-q24.11 and 8q24.13 with the presence of the segment 8q24.12. Therefore, aCGH provides the advantage of better understanding of the nature of interstitial deletion and genotype-phenotype correlation in this case. Show less
Lipoprotein (a) [Lp(a)] is an independent risk factor for atherosclerosis-related events that is under strong genetic control (heritability = 0.68-0.98). However, causal mutations and functional valid Show more
Lipoprotein (a) [Lp(a)] is an independent risk factor for atherosclerosis-related events that is under strong genetic control (heritability = 0.68-0.98). However, causal mutations and functional validation of biological pathways modulating Lp(a) metabolism are lacking. We performed a genome-wide association scan to identify genetic variants associated with Lp(a)-cholesterol levels in the Old Order Amish. We confirmed a previously known locus on chromosome 6q25-26 and found Lp(a) levels also to be significantly associated with a SNP near the APOA5-APOA4-APOC3-APOA1 gene cluster on chromosome 11q23 linked in the Amish to the APOC3 R19X null mutation. On 6q locus, we detected associations of Lp(a)-cholesterol with 118 common variants (P = 5 × 10(-8) to 3.91 × 10(-19)) spanning a ∼5.3 Mb region that included the LPA gene. To further elucidate variation within LPA, we sequenced LPA and identified two variants most strongly associated with Lp(a)-cholesterol, rs3798220 (P = 1.07 × 10(-14)) and rs10455872 (P = 1.85 × 10(-12)). We also measured copy numbers of kringle IV-2 (KIV-2) in LPA using qPCR. KIV-2 numbers were significantly associated with Lp(a)-cholesterol (P = 2.28 × 10(-9)). Conditional analyses revealed that rs3798220 and rs10455872 were associated with Lp(a)-cholesterol levels independent of each other and KIV-2 copy number. Furthermore, we determined for the first time that levels of LPA mRNA were higher in the carriers than non-carriers of rs10455872 (P = 0.0001) and were not different between carriers and non-carriers of rs3798220. Protein levels of apo(a) were higher in the carriers than non-carriers of both rs10455872 and rs3798220. In summary, we identified multiple independent genetic determinants for Lp(a)-cholesterol. These findings provide new insights into Lp(a) regulation. Show less
It has been suggested that retinoic acid (RA) has a potential role in the prevention of atherosclerotic CVD. In the present study, we used J774A.1 cell lines and primary peritoneal macrophages to inve Show more
It has been suggested that retinoic acid (RA) has a potential role in the prevention of atherosclerotic CVD. In the present study, we used J774A.1 cell lines and primary peritoneal macrophages to investigate the protective effects of RA on foam cell formation and atherogenesis in apoE-deficient (apoE- / -) mice. A total of twenty male apoE- / - mice (n 10 animals per group), aged 8 weeks, were fed on a high-fat diet (HFD) and treated with vehicle or 9-cis-RA for 8 weeks. The atherosclerotic plaque area in the aortic sinus of mice in the 9-cis-RA group was 40·7 % less than that of mice in the control group (P< 0·01). Mouse peritoneal macrophages from the 9-cis-RA group had higher protein expression levels of ATP-binding cassette transporter A1 (ABCA1) and G1 (ABCG1) than those from the control group. Serum total and LDL-cholesterol concentrations were lower in the 9-cis-RA group than in the control group (P< 0·05). In vitro studies showed that incubation of cholesterol-loaded J774A.1 macrophages with 9-cis-RA (0·1, 1 and 10 μmol/l) induced cholesterol efflux in a dose-dependent manner. The 9-cis-RA treatment markedly attenuated lipid accumulation in macrophages exposed to oxidised LDL. Moreover, treatment with 9-cis-RA significantly increased the protein expression levels of ABCA1 and ABCG1 in J774A.1 macrophages in a dose-dependent manner. Furthermore, 9-cis-RA dose-dependently enhanced the protein expression level of liver X receptor-α (LXRα), the upstream regulator of ABCA1 and ABCG1. Taken together, the present results show that 9-cis-RA suppresses foam cell formation and prevents HFD-induced atherogenesis via the LXRα-dependent up-regulation of ABCA1 and ABCG1. Show less
Tissue concentrations of omega-3 fatty acids may reduce cardiovascular disease risk, and genetic variants are associated with circulating fatty acids concentrations. Whether dietary fatty acids intera Show more
Tissue concentrations of omega-3 fatty acids may reduce cardiovascular disease risk, and genetic variants are associated with circulating fatty acids concentrations. Whether dietary fatty acids interact with genetic variants to modify circulating omega-3 fatty acids is unclear. We evaluated interactions between genetic variants and fatty acid intakes for circulating alpha-linoleic acid, eicosapentaenoic acid, docosahexaenoic acid, and docosapentaenoic acid. We conducted meta-analyses (N = 11 668) evaluating interactions between dietary fatty acids and genetic variants (rs174538 and rs174548 in FADS1 (fatty acid desaturase 1), rs7435 in AGPAT3 (1-acyl-sn-glycerol-3-phosphate), rs4985167 in PDXDC1 (pyridoxal-dependent decarboxylase domain-containing 1), rs780094 in GCKR (glucokinase regulatory protein), and rs3734398 in ELOVL2 (fatty acid elongase 2)). Stratification by measurement compartment (plasma versus erthyrocyte) revealed compartment-specific interactions between FADS1 rs174538 and rs174548 and dietary alpha-linolenic acid and linoleic acid for docosahexaenoic acid and docosapentaenoic acid. Our findings reinforce earlier reports that genetically based differences in circulating fatty acids may be partially due to differences in the conversion of fatty acid precursors. Further, fatty acids measurement compartment may modify gene-diet relationships, and considering compartment may improve the detection of gene-fatty acids interactions for circulating fatty acid outcomes. Show less
Whole exome sequencing (WES) is a recently developed method for discovering rare mutations associated with hereditary disorders. However, the feasibility and utilization of this method in identifying Show more
Whole exome sequencing (WES) is a recently developed method for discovering rare mutations associated with hereditary disorders. However, the feasibility and utilization of this method in identifying familial hypertriglyceridemia is not well known. The purpose of the study was to identify the genetic locus that causes hypertriglyceridemia and assess its prevalence in Taiwanese subjects with hypertriglyceridemia. We performed WES among two individuals with hypertriglyceridemia and one control subject in an index family (22 members). Based on the WES findings, we extended the study to genotype 65 unrelated adult index patients with a fasting serum triglyceride level of ＞ 500 mg/dL and 125 normal controls using polymerase chain reaction. Using WES alignment, variant calling and annotation, 15 presumptive causal variants were initially identified, including 13 cases by the autosomal dominant model and two cases by the autosomal recessive model. Only APOA5 c.553 G ＞ T (rs2075291), resulting in the amino acid mutation Gly185Cys, co-segregated well with hypertriglyceridemia in terms of autosomal recessive inheritance (homozygote TT: mean triglyceride level: 1,071 mg/dL vs non TT (GT and GG): mean triglyceride level: 118 mg/dL; p ＜ 0.001) in the index family. In the unrelated cohorts, the frequency of the TT genotype of rs2075291 was 12.3% in the hypertriglyceridemic group; however, no TT genotype was found in the control group. Our results demonstrate that WES is feasible for identifying the genetic locus that causes hypertriglyceridemia. The TT genotype of APOA5 c.553G ＞ T acts as an important indicator of hypertriglyceridemia in patients in Taiwan. Show less
We studied the effects of alfalfa saponin extract (ASE) on low density lipoprotein receptor (Ldlr), liver X receptor α (LXRα), and farnesoid X receptor (FXR) in normal and hyperlipidemic Buffalo rat l Show more
We studied the effects of alfalfa saponin extract (ASE) on low density lipoprotein receptor (Ldlr), liver X receptor α (LXRα), and farnesoid X receptor (FXR) in normal and hyperlipidemic Buffalo rat liver (BRL) cells. Normal and hyperlipidemic BRL cells were divided into eight groups: normal, or normal cells treated with 50, 100, and 150 mg/L ASE, hyperlipidemic, or hyperlipidemic cells treated with 50, 100, and 150 mg/L ASE. After treatment for 24 h, Ldlr, LXRα, and FXR mRNA expression levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Data showed that mRNA expression of Ldlr in normal BRL cells was significantly up-regulated by ASE treatment and mRNA expressions of LXRα and FXR were significantly down-regulated both in normal and hyperlipidemic BRL cells after ASE treatment. Thus, ASE might ameliorate hepatic steatosis by regulating genes involved in cholesterol metabolism, including up-regulation of Ldlr as well as down-regulation of LXRα and FXR. Show less
To investigate whether activation of liver X receptors (LXRs) protects N-methyl-D-aspartic (NMDA)-induced retinal neurotoxicity in mice and to explore the underlying mechanism. Inner retinal damage wa Show more
To investigate whether activation of liver X receptors (LXRs) protects N-methyl-D-aspartic (NMDA)-induced retinal neurotoxicity in mice and to explore the underlying mechanism. Inner retinal damage was induced by intravitreal injection of NMDA. A synthetic LXR ligand TO901317 (TO90, 50 mg/kg/d) or vehicle was intragastrically administrated from 3 days before to 1 day or 7 days after NMDA injection. The severity of retinal damage was evaluated with histological analysis and TUNEL staining, and retinal functions were evaluated by ERG. The expressions of caspase-3, bax, bcl-2, TNF-α, and BACE1, the rate-limiting enzyme in the formation of amyloid β (Aβ), in the retina were examined by real-time PCR and ELISA. The levels of LXRs, NF-κB subunit p65, p-p38 mitogen-activated protein kinase (MAPK), and an LXR target gene ABCA1 were detected with real-time PCR and Western blotting. The localization and protein expression of Aβ in the retina was assessed by immunohistochemistry and Western blotting. The NMDA enhanced the expression of LXRβ but not LXRα and ABCA1 in mouse retina. Nevertheless, administration of TO90 after NMDA injection not only enhanced the expression of LXRβ but also upregulated the level of ABCA1, suggesting retinal LXRs were activated in a ligand-dependent manner. The LXRα expression was unchanged in the vehicle and the TO90-treated groups. Activation of LXRβ with TO90 inhibited cell death in the ganglion cell layer (GCL) and inner nuclear layer (INL), preserved ERG b- and a-wave amplitudes, and the b/a ratio in the NMDA-treated mice. Meanwhile, TO90 suppressed the elevation of apoptosis factors caspase-3 and bax induced by NMDA and upregulated the level of an antiapoptotic factor bcl-2. The TO90 also inhibited the increase of p-p38 MAPK and proinflammatory cytokine TNF-α after NMDA injection. Furthermore, activation of LXR attenuated the activation of NF-κB, and reduced gene expression of BACE1 and accumulation of Aβ induced by NMDA. Activation of LXRβ with a synthetic LXR ligand TO90 protects the inner retinal damage induced by NMDA in mice. We speculate the protective effect is associated with inhibition of the NF-κB signaling pathway and reduction of Aβ formation in retina. The LXR agonists may become a new class of neuroprotective agent for retinal diseases associated with glutamate-induced excitotoxicity. Show less
To investigate the transdifferentiation relationship between eight types of liver cell during rat liver regeneration (LR). 114 healthy Sprague-Dawley (SD) rats were used in this experimental study. Ei Show more
To investigate the transdifferentiation relationship between eight types of liver cell during rat liver regeneration (LR). 114 healthy Sprague-Dawley (SD) rats were used in this experimental study. Eight types of liver cell were isolated and purified with percoll density gradient centrifugation and immunomagentic bead methods. Marker genes for eight types of cell were obtained by retrieving the relevant references and databases. Expression changes of markers for each cell of the eight cell types were measured using microarray. The relationships between the expression profiles of marker genes and transdifferentiation among liver cells were analyzed using bioinformatics. Liver cell transdifferentiation was predicted by comparing expression profiles of marker genes in different liver cells. During LR hepatocytes (HCs) not only express hepatic oval cells (HOC) markers (including PROM1, KRT14 and LY6E), but also express biliary epithelial cell (BEC) markers (including KRT7 and KRT19); BECs express both HOC markers (including GABRP, PCNA and THY1) and HC markers such as CPS1, TAT, KRT8 and KRT18; both HC markers (KRT18, KRT8 and WT1) and BEC markers (KRT7 and KRT19) were detected in HOCs. Additionally, some HC markers were also significantly upregulated in hepatic stellate cells ( HSCs), sinusoidal endothelial cells (SECs) , Kupffer cells (KCs) and dendritic cells (DCs), mainly at 6-72 hours post partial hepatectomy (PH). Our findings indicate that there is a mutual transdifferentiation relationship between HC, BEC and HOC during LR, and a tendency for HSCs, SECs, KCs and DCs to transdifferentiate into HCs. Show less
To explore the potential molecular mechanisms involved in migratory glioma cells. The gene expression profiles of GSE28167, employing human malignant glioma U251MG cells cultured on strictly aligned v Show more
To explore the potential molecular mechanisms involved in migratory glioma cells. The gene expression profiles of GSE28167, employing human malignant glioma U251MG cells cultured on strictly aligned versus randomly oriented electrospun nanofibers of polycaprolactone, were downloaded from the Gene Expression Omnibus database. Gene differential expression analysis was carried out by the package of Gene Expression Omnibus query and limma in R language. The Gene Set Analysis Toolkit V2 was used for pathway analysis. Gene set enrichment analysis was used to screen for target sites of transcription factors, miRNA and small drug molecules. Totally 586 differentially expressed genes were identified and the differentially expressed genes were mainly enriched in the pathway of muscle cell TarBase, MAPK cascade, adipogenesis and epithelium TarBase. Thirty-two significant target sites of transcription factors, such as hsa_RTAAACA_V$FREAC2₀₁, were screened. The top 20 potential miRNAs including MIR-124A, MIR-34A and MIR-34C were screened for a constructing gene-miRNA interaction network. Small molecules that can inhibit the motility of glioma cells such as diclofenamide and valinomycin were mined. By integrating the regulatory relationships among transcription factors, miRNAs and differentially expressed genes, we found that 7 differentially expressed genes, including SOX4, ANKRD28 and CCND1, might play crucial roles in the migration of glioma cells. The screened migration-associated genes, significant pathways, and small molecules give us new insight for the mechanism of migratory glioma cells. Interest in such genes as potential target genes in the treatment of glioblastoma justifies functional validation studies. Show less
Cyclosporine A (CsA) increases β-catenin messenger RNA (mRNA) and protein expression. The present study demonstrates that Wnt/β-catenin signaling inhibits β-catenin degradation in the gingiva. Forty 5 Show more
Cyclosporine A (CsA) increases β-catenin messenger RNA (mRNA) and protein expression. The present study demonstrates that Wnt/β-catenin signaling inhibits β-catenin degradation in the gingiva. Forty 5-week-old male Sprague-Dawley rats were assigned to two study groups after healing from right maxillary molar extractions. The rats in the experimental group were fed 30 mg/kg CsA daily for 4 weeks, whereas the control rats were fed mineral oil. At the end of the study, all rats were sacrificed, and the gingivae were obtained. The gingival morphology after CsA treatment was evaluated by histology, and the genes related to Wnt/β-catenin signaling were initially screened by microarray. Polymerase chain reaction, Western blotting, and immunohistochemistry were used to examine the mRNA and protein expression of proliferating cell nuclear antigen, cyclin D1, E-cadherin, β-catenin, Dvl-1, glycogen synthase kinase-3β, axin-1, and adenomatous polyposis coli (APC). Phosphoserine and ubiquitinylated β-catenin were detected after immunoprecipitation. In rats treated with CsA, overgrowth of gingivae was observed, and altered expression of genes related to Wnt/β-catenin signaling was detected by the microarray. The gingival mRNA and protein expression profiles for genes associated with Wnt/β-catenin signaling further confirmed the effect of CsA: β-catenin and Dvl-1 expression increased, but APC and axin-1 expression decreased. Western blotting and immunohistochemistry showed decreases in β-catenin serine phosphorylation (33/37) and ubiquitinylation in the gingivae of CsA-treated rats. CsA-enhanced gingival β-catenin stability may be involved in gene upregulation or β-catenin degradation via the Wnt/β-catenin pathway. Show less
The objective of this study was to investigate the multiple relations between the preliminary molecular structural characteristics and antioxidant activities of polysaccharides from Canarium album (Lo Show more
The objective of this study was to investigate the multiple relations between the preliminary molecular structural characteristics and antioxidant activities of polysaccharides from Canarium album (Lour.) Raeusch (CPS). Three polysaccharide fractions, CPS1, CPS2, and CPS3, were isolated from CPS by column chromatography. CPS1 and CPS3 were mainly composed of neutral polysaccharides linked by α- and β-glycosidic linkages while CPS2 was pectin polysaccharides mainly linked by β-glycosidic linkages. According to the SEC-MALLS-RI system, the molecular weight of CPS1 was greater compared to CPS2 and CPS3, and the molecular weight and radius of CPS did not display positive correlation. The chain conformation analysis indicated CPS1 and CPS2 were typical highly branched polysaccharides while CPS3 existed as a globular shape in aqueous. Furthermore, the antioxidant activity of CPS2 was better than that of CPS3, while that of CPS1 was the weakest. The antioxidant activities of polysaccharide fractions were affected by their monosaccharide composition, glycosidic linkage, molecular weight, and chain conformation. This functional property was a result of a combination of multiple molecular structural factors. CPS2 was the major antioxidant component of CPS and it could be exploited as a valued antioxidant product. The molecular structural characteristics, antioxidant activities, and structure-function relationships of polysaccharide fractions from Canarium album were first investigated in this study. The results provided background and practical knowledge for the deep-processed products of C. album with high added value. CPS2 was the major antioxidant component of CPS, which could be exploited as a valued antioxidant ingredient in food and pharmaceutical industries. Show less
Smooth muscle 22α (SM22α) is involved in stress fiber formation and enhances contractility in vascular smooth muscle cells (VSMCs). In many cases, SM22α acts as an adapter protein to assemble signalin Show more
Smooth muscle 22α (SM22α) is involved in stress fiber formation and enhances contractility in vascular smooth muscle cells (VSMCs). In many cases, SM22α acts as an adapter protein to assemble signaling complexes and regulate signaling, but whether SM22α regulates contractile signaling induced by angiotensin II (AngII) remains unclear. To address this issue, we established a hypertension model of Sm22α(-/-) mice, and demonstrated that hypertension induced by AngII was attenuated in Sm22α(-/-) mice. A decreased vasoconstriction was observed in aortic rings from Sm22α(-/-) mice. Furthermore, loss of SM22α resulted in a reduced contractile response to AngII in VSMCs in vitro. The phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) induced by AngII was impaired following depletion of SM22α, in parallel with a reduced contractility. The decay of ERK1/2 activity was associated with increased expression of mitogen-activated protein kinase phosphatase 3 (MKP3). Inhibition of MKP3 activity rescued ERK1/2 activity. SM22α depletion caused an enhanced interaction of MKP3 with ERK1/2, and a reduced ubiquitination and degradation of MKP3. Knockdown of SM22α extended the half-life of MKP3. In conclusion, SM22α promotes AngII-induced contraction by maintenance of ERK1/2 signaling cascades through facilitating ubiquitination and degradation of MKP3. The vasoconstriction is attenuated in aortic rings from Sm22α(-/-) mice. MKP3 mediates dephosphorylation of ERK1/2 in AngII-induced VSMC contraction. SM22α inhibits the interaction of ERK1/2 with MKP3. SM22α promotes ubiquitination and degradation of MKP3. SM22α facilitates AngII-induced contraction by maintenance of ERK1/2 signaling. Show less