This study examines to what extent plasma linoleic acid (LA) is modified by adiposity, and explores any association between plasma LA, demographics, dietary intakes, markers of metabolic health, and h Show more
This study examines to what extent plasma linoleic acid (LA) is modified by adiposity, and explores any association between plasma LA, demographics, dietary intakes, markers of metabolic health, and haplotypes of the fatty acid desaturase (FADS) 1/2 genes. A total of 820 participants with fasting blood samples from the Irish National Adult Nutrition Survey are studied. Plasma fatty acids are determined using GC-MS. Fifteen SNPs of FADS 1/2 genes are genotyped. Plasma LA decreases, while γ-linoleic acid and dihomo-γ-linoleic acid increases in overweight/obese participants (p ≤ 0.002). Participants in the highest quartile of plasma LA show decreased plasma markers of de novo lipogenesis, insulin resistance, and of inflammation (TNF-α, PAI-1) (p ≤ 0.005). Adiposity (waist circumference and body fat) is strongly inversely associated with plasma LA accounting for 11.8% of variance observed, which is followed by FADS1/2 haplotypes (3.9%), quantity and quality of carbohydrate intakes (3.8%), dietary PUFA intakes (3.7%), systolic blood pressure (3.6%), and age (3.2%). Plasma LA is inversely associated with adiposity, followed by haplotypes of FADS1/2 genes, carbohydrate intakes, and dietary PUFA intakes. The association observed between plasma LA and adiposity may be linked to decreased de novo lipogenesis, insulin resistance, and inflammation. Show less
The enzymes encoded by fatty acid desaturases (FADS) genes determine the desaturation of long-chain polyunsaturated fatty acids (LCPUFA). We investigated if haplotype and single nucleotide polymorphis Show more
The enzymes encoded by fatty acid desaturases (FADS) genes determine the desaturation of long-chain polyunsaturated fatty acids (LCPUFA). We investigated if haplotype and single nucleotide polymorphisms (SNPs) in FADS gene cluster can influence LCPUFA status in infants who received either fish oil or placebo supplementation. Children enrolled in the Infant Fish Oil Supplementation Study (IFOS) were randomly allocated to receive either fish oil or placebo from birth to 6 months of age. Blood was collected at 6 months of age for the measurement of fatty acids and for DNA extraction. A total of 276 participant DNA samples underwent genotyping, and 126 erythrocyte and 133 plasma fatty acid measurements were available for analysis. Twenty-two FADS SNPs were selected on the basis of literature and linkage disequilibrium patterns identified from the HapMap data. Haplotype construction was completed using PHASE. For participants allocated to the fish oil group who had two copies of the FADS1 haplotype consisting of SNP minor alleles, DHA levels were significantly higher compared to other haplotypes. This finding was not observed for the placebo group. Furthermore, for members of the fish oil group only, the minor homozygous carriers of all the FADS1 SNPs investigated had significantly higher DHA than other genotypes (rs174545, rs174546, rs174548, rs174553, rs174556, rs174537, rs174448, and rs174455). Overall results of this preliminary study suggest that supplementation with fish oil may only significantly increase DHA in minor allele carriers of FADS1 SNPs. Further research is required to confirm this novel finding. Show less
Heilongjiang Province located in northeast China is a multi-ethnic region with people who have lived in cold conditions for several generations. Fatty acids are important to people with cold resistanc Show more
Heilongjiang Province located in northeast China is a multi-ethnic region with people who have lived in cold conditions for several generations. Fatty acids are important to people with cold resistance. CPT1A encodes a protein that imports long-chain fatty acids into the mitochondria for fatty-acid oxidation. FADS is an essential enzyme for the synthesis of long-chain polyunsaturated fatty acids. In the present study, we investigated the distributions of three cold resistance-related SNPs (rs80356779 G > A in CPT1A, rs7115739 T > G in FADS3 and rs174570 C > T in FADS2) from six populations that included 1093 individuals who have lived in Heilongjiang Province for at least three generations. The frequencies of rs174570 and rs7115739 were different in our six north minorities compared to the Chinese Dai in Xishuangbanna (CDX) in southern China. All the SNPs in Hezhen were significantly different from other five studied populations. In addition, the genetic distribution of rs174570 in Daur was significantly different from Manchu and Korea, and the frequency of rs7115739 in Ewenki was significantly different from the other populations. The results also showed that the frequencies of the three SNPs in the six minorities were different from those of Greenlandic Inuit and Siberian population. Our results showed the distributions of the three cold resistance-related SNPs from six populations that included 1093 individuals in northern China. Distributions of the allele frequencies for the cold resistance-related SNPs in northern China were statistically different from those in southern China. These data help to establish the DNA genome database for the six populations and fully preserve existing minority genetic information. Show less
Several inherited arrhythmias, including Brugada syndrome and arrhythmogenic cardiomyopathy, primarily affect the right ventricle and can lead to sudden cardiac death. Among many differences, right an Show more
Several inherited arrhythmias, including Brugada syndrome and arrhythmogenic cardiomyopathy, primarily affect the right ventricle and can lead to sudden cardiac death. Among many differences, right and left ventricular cardiomyocytes derive from distinct progenitors, prompting us to investigate how embryonic programming may contribute to chamber-specific conduction and arrhythmia susceptibility. Here, we show that developmental perturbation of Wnt signaling leads to chamber-specific transcriptional regulation of genes important in cardiac conduction that persists into adulthood. Transcriptional profiling of right versus left ventricles in mice deficient in Wnt transcriptional activity reveals global chamber differences, including genes regulating cardiac electrophysiology such as Gja1 and Scn5a. In addition, the transcriptional repressor Hey2, a gene associated with Brugada syndrome, is a direct target of Wnt signaling in the right ventricle only. These transcriptional changes lead to perturbed right ventricular cardiac conduction and cellular excitability. Ex vivo and in vivo stimulation of the right ventricle is sufficient to induce ventricular tachycardia in Wnt transcriptionally inactive hearts, while left ventricular stimulation has no effect. These data show that embryonic perturbation of Wnt signaling in cardiomyocytes leads to right ventricular arrhythmia susceptibility in the adult heart through chamber-specific regulation of genes regulating cellular electrophysiology. Show less
Hey2 gene mutations in both humans and mice have been associated with multiple cardiac defects. However, the currently reported localization of Hey2 in the ventricular compact zone cannot explain the Show more
Hey2 gene mutations in both humans and mice have been associated with multiple cardiac defects. However, the currently reported localization of Hey2 in the ventricular compact zone cannot explain the wide variety of cardiac defects. Furthermore, it was reported that, in contrast to other organs, Notch doesn't regulate Hey2 in the heart. To determine the expression pattern and the regulation of Hey2, we used novel methods including RNAscope and a Hey2 Show less
Accumulating evidence has suggested a link between maternal di-(2-ethylhexyl)-phthalate (DEHP) exposure and various developmental abnormalities. However, the evidence regarding the effect of maternal Show more
Accumulating evidence has suggested a link between maternal di-(2-ethylhexyl)-phthalate (DEHP) exposure and various developmental abnormalities. However, the evidence regarding the effect of maternal DEHP exposure on fetal cardiac development is scarce. The present study aimed to determine the effect of maternal DEHP exposure on fetal cardiac development in mice and explore the possible involved mechanism preliminarily. The C57BL mice were randomly divided into four groups: the vehicle group (corn oil, n = 10), 250 mg kg Show less
Redox active ultrafine particles (UFP, d < 0.2 μm) promote vascular oxidative stress and atherosclerosis. Notch signaling is intimately involved in vascular homeostasis, in which forkhead box O1 (FOXO Show more
Redox active ultrafine particles (UFP, d < 0.2 μm) promote vascular oxidative stress and atherosclerosis. Notch signaling is intimately involved in vascular homeostasis, in which forkhead box O1 (FOXO1) acts as a co-activator of the Notch activation complex. We elucidated the importance of FOXO1/Notch transcriptional activation complex to restore vascular regeneration after UFP exposure. In a zebrafish model of tail injury and repair, transgenic Tg(fli1:GFP) embryos developed vascular regeneration at 3 days post amputation (dpa), whereas UFP exposure impaired regeneration (p < 0.05, n = 20 for control, n = 28 for UFP). UFP dose dependently reduced Notch reporter activity and Notch signaling-related genes (Dll4, JAG1, JAG2, Notch1b, Hey2, Hes1; p < 0.05, n = 3). In the transgenic Tg(tp1:GFP; flk1:mCherry) embryos, UFP attenuated endothelial Notch activity at the amputation site (p < 0.05 vs. wild type [WT], n = 20). A disintegrin and metalloproteinase domain-containing protein 10 (ADAM10) inhibitor or dominant negative (DN)-Notch1b messenger RNA (mRNA) disrupted the vascular network, whereas notch intracellular cytoplasmic domain (NICD) mRNA restored the vascular network (p < 0.05 vs. WT, n = 20). UFP reduced FOXO1 expression, but not Master-mind like 1 (MAML1) or NICD (p < 0.05, n = 3). Immunoprecipitation and immunofluorescence demonstrated that UFP attenuated FOXO1-mediated NICD pull-down and FOXO1/NICD co-localization, respectively (p < 0.05, n = 3). Although FOXO1 morpholino oligonucleotides (MOs) attenuated Notch activity, FOXO1 mRNA reversed UFP-mediated reduction in Notch activity to restore vascular regeneration and blood flow (p < 0.05 vs. WT, n = 5). Innovation and Conclusion: Our findings indicate the importance of the FOXO1/Notch activation complex to restore vascular regeneration after exposure to the redox active UFP. Antioxid. Redox Signal. 28, 1209-1223. Show less
Non-small-cell lung cancer (NSCLC) has been recognized as a highly heterogeneous disease with phenotypic and genotypic diversity in each subgroup. While never-smoker patients with NSCLC have been well Show more
Non-small-cell lung cancer (NSCLC) has been recognized as a highly heterogeneous disease with phenotypic and genotypic diversity in each subgroup. While never-smoker patients with NSCLC have been well studied through next generation sequencing, we have yet to recognize the potentially unique molecular features of young never-smoker patients with NSCLC. In this study, we conducted whole genome sequencing (WGS) to characterize the genomic alterations of 36 never-smoker Chinese patients, who were diagnosed with lung adenocarcinoma (LUAD) at 45 years or younger. Besides the well-known gene mutations (e.g., TP53 and EGFR), our study identified several potential lung cancer-associated gene mutations that were rarely reported (e.g., HOXA4 and MST1). The lung cancer-related copy number variations (e.g., EGFR and CDKN2A) were enriched in our cohort (41.7%, 15/36) and the lung cancer-related structural variations (e.g., EML4-ALK and KIF5B-RET) were commonly observed (22.2%, 8/36). Notably, new fusion partners of ALK (SMG6-ALK) and RET (JMJD1C-RET) were found. Furthermore, we observed a high prevalence (63.9%, 23/36) of potentially targetable genomic alterations in our cohort. Finally, we identified germline mutations in BPIFB1 (rs6141383, p.V284M), CHD4 (rs74790047, p.D140E), PARP1 (rs3219145, p.K940R), NUDT1 (rs4866, p.V83M), RAD52 (rs4987207, p.S346*), and MFI2 (rs17129219, p.A559T) were significantly enriched in the young never-smoker patients with LUAD when compared with the in-house noncancer database (p < 0.05). Our study provides a detailed mutational portrait of LUAD occurring in young never-smokers and gives insights into the molecular pathogenesis of this distinct subgroup of NSCLC. Show less
Multiple evidence has indicated that myelin injury is common in Alzheimer's disease (AD). However, whether myelin injury is an early event in AD and the relationship between it and cognitive function Show more
Multiple evidence has indicated that myelin injury is common in Alzheimer's disease (AD). However, whether myelin injury is an early event in AD and the relationship between it and cognitive function is still elusive. Spatial memory of 5XFAD mice was determined by Morris water maze at 1 and 3 months old. Meanwhile, the deposition of Aβ, the expression of myelin basic protein (MBP), LINGO-1, NgR, and myelin ultrastructure in many memory-associated brain regions were detected in one-month-old and three-month-old mice (before and after LINGO-1 antibody administration) using immunostaining, Western blot (WB), and transmission electron microscopy (TEM), respectively. No abnormal Aβ deposition was found in one-month-old 5XFAD mice. However, spatial memory deficits were proved in accordance with an obvious demyelination in memory-associated brain regions in one-month-old mice and both deteriorated with age. Administration of LINGO-1 antibody could obviously restore the myelin impairments in CA1 and DG region and partially ameliorate spatial memory deficits. Our results demonstrated that myelin injury was an early event in 5XFAD mice even prior to emergence of deposition of Aβ. Intervention with the LINGO-1 antibody could attenuate impaired spatial memory deficits by remyelination, which suggested that myelin injury was involved in spatial memory deficits and remyelination may be a potential therapeutic strategy in early stage of AD or mild cognitive impairments. Show less
Seizure-induced brain damage is age-dependent, as evidenced by the different alterations of neural physiopathology in developing and mature brains. However, little is known about the age-dependent cha Show more
Seizure-induced brain damage is age-dependent, as evidenced by the different alterations of neural physiopathology in developing and mature brains. However, little is known about the age-dependent characteristics of myelinated fiber injury induced by seizures. Considering the critical functions of oligodendrocyte progenitor cells (OPCs) in myelination and Lingo-1 signaling in regulating OPCs' differentiation, the present study aimed to explore the effects of Lingo-1 on myelin and axon in immature and adult rats after status convulsion (SC) induced by lithium-pilocarpine, and the differences between immature and adult brains. Dynamic variations in electrophysiological activity and spontaneous recurrent seizures were recorded by electroencephalogram monitoring after SC. The impaired microstructures of myelin sheaths and decrease in myelin basic protein caused by SC were observed through transmission electron microscopy and western blot analysis respectively, which became more severe in adult rats, but improved gradually in immature rats. Aberrant axon sprouting occurred in adult rats, which was more prominent than in immature rats, as shown by a Timm stain. This damage was improved or negatively affected after down or upregulating Lingo-1 expression. These results demonstrated that in both immature and adult brains, Lingo-1 signaling plays important roles in seizure-induced damage to myelin sheaths and axon growth. The plasticity of the developing brain may provide a potential window of opportunity to prevent the brain from damage. Show less
Microtubule actin crosslinking factor 1 (MACF1) is a large spectraplakin protein known to have crucial roles in regulating cytoskeletal dynamics, cell migration, growth, and differentiation. However, Show more
Microtubule actin crosslinking factor 1 (MACF1) is a large spectraplakin protein known to have crucial roles in regulating cytoskeletal dynamics, cell migration, growth, and differentiation. However, its role and action mechanism in bone remain unclear. The present study investigated optimal conditions for effective transfection of the large plasmid PEGFP-C1A-ACF7 (∼21 kbp) containing full-length human MACF1 cDNA, as well as the potential role of MACF1 in bone formation. To enhance MACF1 expression, the plasmid was transfected into osteogenic cells by electroporation in vitro and into mouse calvaria with nanoparticles. Then, transfection efficiency, osteogenic marker expression, calvarial thickness, and bone formation were analyzed. Notably, MACF1 overexpression triggered a drastic increase in osteogenic gene expression, alkaline phosphatase activity, and matrix mineralization in vitro. Mouse calvarial thickness, mineral apposition rate, and osteogenic marker protein expression were significantly enhanced by local transfection. In addition, MACF1 overexpression promoted β-catenin expression and signaling. In conclusion, MACF1 overexpression by transfecting the large plasmid containing full-length MACF1 cDNA promotes osteoblast differentiation and bone formation via β-catenin signaling. Current data will provide useful experimental parameters for the transfection of large plasmids and a novel strategy based on promoting bone formation for prevention and therapy of bone disorders. Show less
Mechanical unloading was considered a major threat to bone homeostasis, and has been shown to decrease osteoblast proliferation although the underlying mechanism is unclear. Microtubule actin crosslin Show more
Mechanical unloading was considered a major threat to bone homeostasis, and has been shown to decrease osteoblast proliferation although the underlying mechanism is unclear. Microtubule actin crosslinking factor 1 (MACF1) is a cytoskeletal protein that regulates cellular processes and Wnt/β-catenin pathway, an essential signaling pathway for osteoblasts. However, the relationship between MACF1 expression and mechanical unloading, and the function and the associated mechanisms of MACF1 in regulating osteoblast proliferation are unclear. This study investigated effects of mechanical unloading on MACF1 expression levels in cultured MC3T3-E1 osteoblastic cells and in femurs of mice with hind limb unloading; and it also examined the role and potential action mechanisms of MACF1 in osteoblast proliferation in MACF1-knockdown, overexpressed or control MC3T3-E1 cells treated with or without the mechanical unloading condition. Results showed that the mechanical unloading condition inhibited osteoblast proliferation and MACF1 expression in MC3T3-E1 osteoblastic cells and mouse femurs. MACF1 knockdown decreased osteoblast proliferation, while MACF1 overexpression increased it. The inhibitory effect of mechanical unloading on osteoblast proliferation also changed with MACF1 expression levels. Furthermore, MACF1 was found to enhance β-catenin expression and activity, and mechanical unloading decreased β-catenin expression through MACF1. Moreover, β-catenin was found an important regulator of osteoblast proliferation, as its preservation by treatment with its agonist lithium attenuated the inhibitory effects of MACF1-knockdown or mechanical unloading on osteoblast proliferation. Taken together, mechanical unloading decreases MACF1 expression, and MACF1 up-regulates osteoblast proliferation through enhancing β-catenin signaling. This study has thus provided a mechanism for mechanical unloading-induced inhibited osteoblast proliferation. Show less
Osteoblast differentiation is a multistep process delicately regulated by many factors, including cytoskeletal dynamics and signaling pathways. Microtubule actin crosslinking factor 1 (MACF1), a key c Show more
Osteoblast differentiation is a multistep process delicately regulated by many factors, including cytoskeletal dynamics and signaling pathways. Microtubule actin crosslinking factor 1 (MACF1), a key cytoskeletal linker, has been shown to play key roles in signal transduction and in diverse cellular processes; however, its role in regulating osteoblast differentiation is still needed to be elucidated. To further uncover the functions and mechanisms of action of MACF1 in osteoblast differentiation, we examined effects of MACF1 knockdown (MACF1-KD) in MC3T3-E1 osteoblastic cells on their osteoblast differentiation and associated molecular mechanisms. The results showed that knockdown of MACF1 significantly suppressed mineralization of MC3T3-E1 cells, down-regulated the expression of key osteogenic genes alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2) and type I collagen α1 (Col Iα1). Knockdown of MACF1 dramatically reduced the nuclear translocation of β-catenin, decreased the transcriptional activation of T cell factor 1 (TCF1), and down-regulated the expression of TCF1, lymphoid enhancer-binding factor 1 (LEF1), and Runx2, a target gene of β-catenin/TCF1. In addition, MACF1-KD increased the active level of glycogen synthase kinase-3β (GSK-3β), which is a key regulator for β-catenin signal transduction. Moreover, the reduction of nuclear β-catenin amount and decreased expression of TCF1 and Runx2 were significantly reversed in MACF1-KD cells when treated with lithium chloride, an agonist for β-catenin by inhibiting GSK-3β activity. Taken together, these findings suggest that knockdown of MACF1 in osteoblastic cells inhibits osteoblast differentiation through suppressing the β-catenin/TCF1-Runx2 axis. Thus, a novel role of MACF1 in and a new mechanistic insight of osteoblast differentiation are uncovered. Show less
Tyrosine kinase inhibitors (TKi) are effective against chronic myeloid leukemia (CML), but their inefficacy on leukemia stem cells (LSCs) may lead to relapse. To identify new druggable targets alterna Show more
Tyrosine kinase inhibitors (TKi) are effective against chronic myeloid leukemia (CML), but their inefficacy on leukemia stem cells (LSCs) may lead to relapse. To identify new druggable targets alternative to BCR/ABL, we investigated the role of the MEK5/ERK5 pathway in LSC maintenance in low oxygen, a feature of bone marrow stem cell niches. We found that MEK5/ERK5 pathway inhibition reduced the growth of CML patient-derived cells and cell lines in vitro and the number of leukemic cells in vivo. Treatment in vitro of primary CML cells with MEK5/ERK5 inhibitors, but not TKi, strikingly reduced culture repopulation ability (CRA), serial colony formation ability, long-term culture-initiating cells (LTC-ICs), and CD26-expressing cells. Importantly, MEK5/ERK5 inhibition was effective on CML cells regardless of the presence or absence of imatinib, and did not reduce CRA or LTC-ICs of normal CD34+ cells. Thus, targeting MEK/ERK5 may represent an innovative therapeutic approach to suppress CML progenitor/stem cells. Show less
Type 2 diabetes (T2D) is generally regarded as a metabolic disorder disease with various phenotypic expressions. Traditional Chinese medicine (TCM) has been widely used for preventing and treating dia Show more
Type 2 diabetes (T2D) is generally regarded as a metabolic disorder disease with various phenotypic expressions. Traditional Chinese medicine (TCM) has been widely used for preventing and treating diabetes. In our study, we demonstrated that Cyclocarya paliurus formula extractum (CPE), a compound of TCM, can ameliorate diabetes in diabetic rats. Transcriptome profiles were performed to elucidate the anti-diabetic mechanisms of CPE on pancreas and liver. Pancreatic transcriptome analysis showed CPE treatment significantly inhibited gene expressions related to inflammation and apoptosis pathways, among which the transcription factors (TFs) nuclear factor κB (NF-κB), STAT, and miR-9a/148/200 may serve as core regulators contributing to ameliorate diabetes. Biochemical studies also demonstrated CPE treatment decreased pro-inflammatory cytokines (tumor necrosis factor alpha [TNF-α], interleukin [IL]-1β, and IL-6) and reduced β cell apoptosis. In liver tissue, our transcriptome and biochemical experiments showed that CPE treatment reduced lipid accumulation and liver injury, and it promoted glycogen synthesis, which may be regulated by TFs Srebf1, Mlxipl, and miR-122/128/192. Taken together, our findings revealed CPE could be used as a potential therapeutic agent to prevent and treat diabetes. It is the first time to combine transcriptome and regulatory network analyses to study the mechanism of CPE in preventing diabetes, giving a demonstration of exploring the mechanism of TCM on complex diseases. Show less
Metabolic reprogramming is a hallmark of many cancer types, including hepatocellular carcinoma (HCC). Identifying the critical players in this process might be crucial for the generation of novel and Show more
Metabolic reprogramming is a hallmark of many cancer types, including hepatocellular carcinoma (HCC). Identifying the critical players in this process might be crucial for the generation of novel and effective anti-neoplastic therapies. In the present investigation, we determined the importance of carbohydrate responsive element binding protein (ChREBP), a central player in the regulation of lipid and glucose metabolism in the liver, on the development of HCC in in vitro and in vivo models. We found that genetic deletion of ChREBP (that will be referred to as ChREBPKO mice) strongly delays or impairs hepatocarcinogenesis driven by AKT or AKT/c-Met overexpression in mice, respectively. In contrast, HCC development was found to be completely unaffected by ChREBP depletion in mice co-expressing AKT and N-Ras protooncogenes. In mouse and human HCC cell lines, suppression of ChREBP via specific small interfering RNAs (siRNAs) resulted in decreased proliferation and induction of apoptosis. Of note, these cellular events were strongly augmented by concomitant inhibition of the mitogen-activated protein kinase (MAPK) pathway. The present data indicate that ChREBP activity might be required or dispensable for HCC growth, depending on the oncogenes involved. In particular, the activation of Ras/MAPK signaling might represent a possible mechanism of resistance to ChREBP depletion in this tumor type. Additional studies are needed to unravel the molecular mechanisms rendering HCC cells insensitive to ChREBP suppression. Show less
Dairy cows with type II ketosis display hepatic fat accumulation and hyperinsulinemia, but the underlying mechanism is not completely clear. This study aimed to clarify the regulation of lipid metabol Show more
Dairy cows with type II ketosis display hepatic fat accumulation and hyperinsulinemia, but the underlying mechanism is not completely clear. This study aimed to clarify the regulation of lipid metabolism by insulin in cow hepatocytes. In vitro, cow hepatocytes were treated with 0, 1, 10, or 100 nm insulin in the presence or absence of AICAR (an AMP-activated protein kinase alpha (AMPKα) activator). The results showed that insulin decreased AMPKα phosphorylation. This inactivation of AMPKα increased the gene and protein expression levels of carbohydrate responsive element-binding protein (ChREBP) and sterol regulatory element-binding protein-1c (SREBP-1c), which downregulated the expression of lipogenic genes, thereby decreasing lipid biosynthesis. Furthermore, AMPKα inactivation decreased the gene and protein expression levels of peroxisome proliferator-activated receptor-α (PPARα), which upregulated the expression of lipid oxidation genes, thereby increasing lipid oxidation. In addition, insulin decreased the very low density lipoprotein (VLDL) assembly. Consequently, triglyceride content was significantly increased in insulin treated hepatocytes. Activation of AMPKα induced by AICAR could reverse the effect of insulin on PPARα, SREBP-1c, and ChREBP, thereby decreasing triglyceride content. These results indicate that insulin inhibits the AMPKα signaling pathway to increase lipid synthesis and decrease lipid oxidation and VLDL assembly in cow hepatocytes, thereby inducing TG accumulation. This mechanism could partly explain the causal relationship between hepatic fat accumulation and hyperinsulinemia in dairy cows with type II ketosis. Show less
Patients with both major forms of diabetes would benefit from therapies that increase β-cell mass. Glucose, a natural mitogen, drives adaptive expansion of β-cell mass by promoting β-cell proliferatio Show more
Patients with both major forms of diabetes would benefit from therapies that increase β-cell mass. Glucose, a natural mitogen, drives adaptive expansion of β-cell mass by promoting β-cell proliferation. We previously demonstrated that a carbohydrate response element-binding protein (ChREBPα) is required for glucose-stimulated β-cell proliferation and that overexpression of ChREBPα amplifies the proliferative effect of glucose. Here we found that ChREBPα reprogrammed anabolic metabolism to promote proliferation. ChREBPα increased mitochondrial biogenesis, oxygen consumption rates, and ATP production. Proliferation augmentation by ChREBPα required the presence of ChREBPβ. ChREBPα increased the expression and activity of Nrf2, initiating antioxidant and mitochondrial biogenic programs. The induction of Nrf2 was required for ChREBPα-mediated mitochondrial biogenesis and for glucose-stimulated and ChREBPα-augmented β-cell proliferation. Overexpression of Nrf2 was sufficient to drive human β-cell proliferation in vitro; this confirms the importance of this pathway. Our results reveal a novel pathway necessary for β-cell proliferation that may be exploited for therapeutic β-cell regeneration. Show less
This study investigated the effect of angiotensin II (Ang II) on apoptosis and thioredoxin-interacting protein (TXNIP) expression in INS-1 islet cells and the underlying mechanism. INS-1 cells culture Show more
This study investigated the effect of angiotensin II (Ang II) on apoptosis and thioredoxin-interacting protein (TXNIP) expression in INS-1 islet cells and the underlying mechanism. INS-1 cells cultured in vitro were treated with different concentration of Ang II for different time, and the viability was measured using cell counting kit-8 (CCK-8). After treatment with 1 × 10 Show less
Lipogenesis in liver is highest in the postprandial state; insulin activates SREBP-1c, which transcriptionally activates genes involved in FA synthesis, whereas glucose activates carbohydrate-responsi Show more
Lipogenesis in liver is highest in the postprandial state; insulin activates SREBP-1c, which transcriptionally activates genes involved in FA synthesis, whereas glucose activates carbohydrate-responsive element-binding protein (ChREBP), which activates both glycolysis and FA synthesis. Whether SREBP-1c and ChREBP act independently of one another is unknown. Here, we characterized mice with liver-specific deletion of ChREBP ( Show less
Brown adipose tissue (BAT) is a therapeutic target for metabolic diseases; thus, understanding its metabolic circuitry is clinically important. Many studies of BAT compare rodents mildly cold to those Show more
Brown adipose tissue (BAT) is a therapeutic target for metabolic diseases; thus, understanding its metabolic circuitry is clinically important. Many studies of BAT compare rodents mildly cold to those severely cold. Here, we compared BAT remodeling between thermoneutral and mild-cold-adapted mice, conditions more relevant to humans. Although BAT is renowned for catabolic β-oxidative capacity, we find paradoxically that the anabolic de novo lipogenesis (DNL) genes encoding ACLY, ACSS2, ACC, and FASN were among the most upregulated by mild cold and that, in humans, DNL correlates with Ucp1 expression. The regulation and function of adipocyte DNL and its association with thermogenesis are not understood. We provide evidence suggesting that AKT2 drives DNL in adipocytes by stimulating ChREBPβ transcriptional activity and that cold induces the AKT2-ChREBP pathway in BAT to optimize fuel storage and thermogenesis. These data provide insight into adipocyte DNL regulation and function and illustrate the metabolic flexibility of thermogenesis. Show less
Sugar-sweetened beverages (SSBs) are a major dietary contributor to fructose intake. A molecular pathway involving the carbohydrate responsive element-binding protein (ChREBP) and the metabolic hormon Show more
Sugar-sweetened beverages (SSBs) are a major dietary contributor to fructose intake. A molecular pathway involving the carbohydrate responsive element-binding protein (ChREBP) and the metabolic hormone fibroblast growth factor 21 (FGF21) may influence sugar metabolism and, thereby, contribute to fructose-induced metabolic disease. We hypothesise that common variants in 11 genes involved in fructose metabolism and the ChREBP-FGF21 pathway may interact with SSB intake to exacerbate positive associations between higher SSB intake and glycaemic traits. Data from 11 cohorts (six discovery and five replication) in the CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology) Consortium provided association and interaction results from 34,748 adults of European descent. SSB intake (soft drinks, fruit punches, lemonades or other fruit drinks) was derived from food-frequency questionnaires and food diaries. In fixed-effects meta-analyses, we quantified: (1) the associations between SSBs and glycaemic traits (fasting glucose and fasting insulin); and (2) the interactions between SSBs and 18 independent SNPs related to the ChREBP-FGF21 pathway. In our combined meta-analyses of discovery and replication cohorts, after adjustment for age, sex, energy intake, BMI and other dietary covariates, each additional serving of SSB intake was associated with higher fasting glucose (β ± SE 0.014 ± 0.004 [mmol/l], p = 1.5 × 10 In this large meta-analysis, we observed that SSB intake was associated with higher fasting glucose and insulin. Although a suggestive interaction with a genetic variant in the ChREBP-FGF21 pathway was observed in the discovery cohorts, this observation was not confirmed in the replication analysis. Trials related to this study were registered at clinicaltrials.gov as NCT00005131 (Atherosclerosis Risk in Communities), NCT00005133 (Cardiovascular Health Study), NCT00005121 (Framingham Offspring Study), NCT00005487 (Multi-Ethnic Study of Atherosclerosis) and NCT00005152 (Nurses' Health Study). Show less
Diminished cardiac contractile function is a characteristic feature of dilated cardiomyopathy (DCM) and many other heart failure (HF) causing etiologies. We tested the hypothesis that targeting the sa Show more
Diminished cardiac contractile function is a characteristic feature of dilated cardiomyopathy (DCM) and many other heart failure (HF) causing etiologies. We tested the hypothesis that targeting the sarcomere to increase cardiac contractility can effectively prevent the DCM phenotype in muscle-LIM protein knockout (MLP Show less
Cardiomyopathies are the most common clinical and genetic heterogeneity cardiac diseases, and genetic contribution in particular plays a major role in patients with primary cardiomyopathies. The aim o Show more
Cardiomyopathies are the most common clinical and genetic heterogeneity cardiac diseases, and genetic contribution in particular plays a major role in patients with primary cardiomyopathies. The aim of this study is to investigate cases of inherited cardiomyopathy (IC) for potential disease-causing mutations in 64 genes reported to be associated with IC. A total of 110 independent cases or families diagnosed with various primary cardiomyopathies, including hypertrophic cardiomyopathy, dilated cardiomyopathy, restrictive cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, left ventricular non-compaction, and undefined cardiomyopathy, were collected after informed consent. A custom designed panel, including 64 genes, was screened using next generation sequencing on the Ion Torrent PGM platform. The best candidate disease-causing variants were verified by Sanger sequencing. A total of 78 variants in 73 patients were identified. After excluding the variants predicted to be benign and VUS, 26 pathogenic or likely pathogenic variants were verified in 26 probands (23.6%), including a homozygous variant in the SLC25A4 gene. Of these variants, 15 have been reported in the Human Gene Mutation Database or ClinVar database, while 11 are novel. The majority of variants were observed in the MYH7 (8/26) and MYBPC3 (6/26) gene. Titin (TTN) truncating mutations account for 13% in our dilated cardiomyopathy cases (3/23). This study provides an overview of the genetic aberrations in this cohort of Chinese IC patients and demonstrates the power of next generation sequencing in IC. Genetic results can provide precise clinical diagnosis and guidance regarding medical care for some individuals. Show less
Gastric cancer (GC) is one of the most common cancers and is the second-leading cause of cancer-associated morbidity worldwide. Oxysterols are oxidized derivatives of cholesterol that may be important Show more
Gastric cancer (GC) is one of the most common cancers and is the second-leading cause of cancer-associated morbidity worldwide. Oxysterols are oxidized derivatives of cholesterol that may be important in many biological processes, but the levels and roles of oxysterols in gastric tumours remain to be elucidated. The levels of cholesterol, oxysterols and sulfated oxysterols in human gastric tumour tissues, adjacent normal mucosal tissues, cancerous gastric juice and gastric juice obtained from healthy subjects were detected by LC-MS. It was found that the levels of 24(R/S),25-EC and 27HC in human gastric tumour tissues and cancerous gastric juice were significantly increased compared with those of adjacent normal mucosal tissues and gastric juice from healthy subjects. Compared with normal gastric mucosal tissue, the levels of sulfated 25-hydroxycholesterol (25HC3S) and the ratio of 25HC3S/25HC were decreased in human gastric tumour tissues, which might be related to the dramatically decreased SULT2A1 expression in gastric tumour tissue. Both 24(R/S),25-EC and 27HC suppressed gastric cancer proliferation, which was not altered by LXRα-siRNA treatment. The suppression of cell proliferation induced by 27HC was attenuated by LXRβ-siRNA, but the suppression of cell proliferation induced by 24(R/S),25-EC was intensified by LXRβ-siRNA. Both 24(R/S),25-EC and 27HC dramatically inhibited HGC-27 cell migration, which was attenuated by the co-transfection of cells with LXRα-siRNA and LXRβ-siRNA, but not LXRα-siRNA or LXRβ-siRNA alone. In conclusion, the accumulated 24(R/S),25-EC and 27HC in human gastric tumour tissues might play important roles in gastric cancer development. Show less
The novel neurite outgrowth inhibitor B (Nogo‑B) receptor (NgBR) is specific for Nogo‑B, which is highly expressed in various human organs and cells, including the lung, liver, kidney, smooth muscle c Show more
The novel neurite outgrowth inhibitor B (Nogo‑B) receptor (NgBR) is specific for Nogo‑B, which is highly expressed in various human organs and cells, including the lung, liver, kidney, smooth muscle cells, blood vessel endothelial cells and inflammatory cells. Previous studies have indicated that NgBR directly interacts with Nogo‑B and is able to independently influence lipid and cholesterol homeostasis, angiogenesis, N‑glycosylation, the epithelial-mesenchymal transition, the chemotaxis of endothelial cells and cellular proliferation and apoptosis. These multiple functions and actions of this receptor provide an understanding of the important roles of NgBR in various conditions, including fatty liver, atherosclerosis, intracranial microaneurysms, retinitis pigmentosa and severe neurological impairment. Furthermore, NgBR has been demonstrated to exert protean, multifunctional and enigmatic effects in cancer. The present review summarizes the latest knowledge on the suppressing and activating effects of NgBR, emphasizing its function in cancer. Further basic and medical research on this receptor may provide novel insight into its clinical implications on the prognosis of relevant human cancer types. Show less
To characterize the association between epilepsy, use of antiepileptic drugs (AEDs), and the risk of hyperlipidemia, we conducted a nationwide population-based cohort study with data obtained from the Show more
To characterize the association between epilepsy, use of antiepileptic drugs (AEDs), and the risk of hyperlipidemia, we conducted a nationwide population-based cohort study with data obtained from the National Health Insurance Research Database of Taiwan. The effects of AEDs on lipogenic gene expression were also examined in vitro. We identified 3617 cases involving patients, whose epilepsy was newly diagnosed between 2000 and 2011, and selected a comparison cohort comprising 14,468 patients without epilepsy. The Cox proportional hazards model was used to evaluate the association between epilepsy, AED use, and hyperlipidemia. The incidence rate of hyperlipidemia was higher in the epilepsy cohort than in the comparison cohort, with an adjusted hazard ratio (aHR) of 1.21 [95% confidence interval (CI): 1.06-1.38] after adjusting for comorbidities and medications. Epilepsy patients not taking AEDs had a higher risk of hyperlipidemia (aHR 1.65; 95% CI 1.35-2.03). Among AEDs, only valproate treatment showed a higher risk of hyperlipidemia (aHR 1.53; 95% CI 1.01-2.33), although the dose-dependent effect did not reach statistical significance. In vitro studies with two hepatic cell lines showed that valproate may exert its effects by activating the liver X receptor alpha (LXRα) signaling pathway, inducing the expression of lipogenesis-related genes and increasing cellular lipid contents. In silico calculations concluded that valproate can bind stably with the ligand-binding domain of LXRα. Thus, valproate-induced hepatic lipogenic gene expression may occur through LXRα activation. Predicting the 'off-target' effects of valproate may prove valuable in developing antiepileptic agents with fewer adverse reactions. Monitoring blood lipid levels throughout the course of treatment is recommended. Show less
Sirtuin 1 (SIRT1) is a nicotinamide adenine dinucleotide-dependent protein deacetylase. Recent studies have demonstrated that enhancing SIRT1 expression or activity may modulate cholesterol and lipid Show more
Sirtuin 1 (SIRT1) is a nicotinamide adenine dinucleotide-dependent protein deacetylase. Recent studies have demonstrated that enhancing SIRT1 expression or activity may modulate cholesterol and lipid metabolism. However, pharmacological and molecular regulators for SIRT1 are scarce. Here, we aimed to find novel small molecule modulators of SIRT1 to regulate cholesterol and lipid metabolism. A high-throughput screening assay was established to identify SIRT1 activators. Surface plasmon resonance and immunoprecipitation were performed to confirm the interaction of E1231 with SIRT1. Cholesterol assay was performed to demonstrate the in vitro effect of E1231. The in vivo effect of E1231 was evaluated in experimental models. E1231, a piperazine 1,4-diamide compound, was identified as a SIRT1 activator with EC We identified a novel SIRT1 activator E1231 and elucidated its beneficial effects on lipid and cholesterol metabolism. Our study suggests that E1231 might be developed as a novel drug for treating atherosclerosis. Show less