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Obesity is a risk factor for breast cancer and also predicts poor clinical outcomes regardless of menopausal status. Contributing to the poor clinical outcomes is the suboptimal efficacy of standard therapies due to dose limiting toxicities and obesity-related complications, highlighting the need to develop novel therapeutic approaches for treating obese patients. We recently found that obesity leads to an increase in tumor-infiltrating macrophages with activated NLRC4 inflammasome and increased interleukin (IL)-1β production. IL-1β, in turn, leads to increased angiogenesis and cancer progression. Using Next Generation RNA sequencing, we identified an NLRC4/IL-1β-dependent upregulation of angiopoietin-like 4 (ANGPTL4), a known angiogenic factor in cancer, in tumors from obese mice. ANGPTL4-deficiency by genetic knockout or treatment with a neutralizing antibody led to a significant reduction in obesity-induced angiogenesis and tumor growth. At a mechanistic level, ANGPTL4 expression is induced by IL-1β from primary adipocytes in a manner dependent on NF-κB- and MAP kinase-activation, which is further enhanced by hypoxia. This report shows that adipocyte-derived ANGPTL4 drives disease progression under obese conditions and is a potential therapeutic target for treating obese breast cancer patients. Show less

Animal studies indicate that the composition of gut microbiota may be involved in the progression of insulin resistance to type 2 diabetes. Probiotics and/or prebiotics could be a promising approach to improve insulin sensitivity by favourably modifying the composition of the gut microbial community, reducing intestinal endotoxin concentrations and decreasing energy harvest. The aim of the present review was to investigate the effects of probiotics, prebiotics and synbiotics (a combination of probiotics and prebiotics) on insulin resistance in human clinical trials and to discuss the potential mechanisms whereby probiotics and prebiotics improve glucose metabolism. The anti-diabetic effects of probiotics include reducing pro-inflammatory cytokines via a NF-κB pathway, reduced intestinal permeability, and lowered oxidative stress. SCFA play a key role in glucose homeostasis through multiple potential mechanisms of action. Activation of G-protein-coupled receptors on L-cells by SCFA promotes the release of glucagon-like peptide-1 and peptide YY resulting in increased insulin and decreased glucagon secretion, and suppressed appetite. SCFA can decrease intestinal permeability and decrease circulating endotoxins, lowering inflammation and oxidative stress. SCFA may also have anti-lipolytic activities in adipocytes and improve insulin sensitivity via GLUT4 through the up-regulation of 5'-AMP-activated protein kinase signalling in muscle and liver tissues. Resistant starch and synbiotics appear to have favourable anti-diabetic effects. However, there are few human interventions. Further well-designed human clinical studies are required to develop recommendations for the prevention of type 2 diabetes with pro- and prebiotics. Show less

Regular exercise plays an important role in the prevention and treatment of type 2 diabetes (T2D). The synthesis and secretion of myokines in response to contraction may contribute to the beneficial metabolic effects of exercise. However, some exercise-induced responses may be attenuated in T2D. Here, we investigated whether the effect of acute exercise on selected myokines are impaired in T2D. Skeletal muscle biopsies and blood samples were obtained from 13 men with T2D and 14 weight-matched, glucose-tolerant men before, immediately after and 3-h after acute exercise (60 min cycling) to examine muscle expression and plasma/serum levels of selected myokines. One-hour of exercise increased muscle expression of IL6, FGF21, ANGPTL4, CHI3L1, CTGF and CYR61, of which FGF21, ANGPTL4 and CHI3L1 increased further 3-h into recovery, whereas expression of IL6, CYR61, and CTGF returned to baseline levels. There was no immediate effect of exercise on IL15 expression, but it decreased 3-h into recovery. Plasma IL-6 increased robustly, whereas circulating levels of FGF21, ANGPTL4, IL-15, and CHI3L1 increased only modestly in response to exercise. All returned toward baseline levels 3-h into recovery except for plasma ANGPTL4, which increased further. No significant differences in these responses to exercise were observed between the groups. Our results demonstrate that muscle expression and circulating levels of selected known and putative myokines were equally regulated by acute exercise in patients with T2D and weight-matched controls. This suggests that the potential beneficial metabolic effects of these myokines are not impaired in patients with T2D. Show less

Our aim was to study the expression of adipokine-encoding genes (leptin, adiponectin, and angiopoietin-like protein 4 (ANGPTL4)) in human umbilical vein endothelial cells (HUVECs) and adipokine concentration in cord blood from women with gestational diabetes mellitus (GDM) depending on glycaemic targets. GDM patients were randomised to 2 groups per target glycaemic levels: GDM1 (tight glycaemic targets, fasting blood glucose < 5.1 mmol/L and <7.0 mmol/L postprandial, Show less

Gastric antral vascular ectasia (GAVE) is a rare vasculopathy that associates several diseases, most commonly liver cirrhosis. It usually presents as an occult gastrointestinal bleeding leading to profound iron deficiency anemia. We hypothesized that GAVE is local mucosal pathology dependent on genetic mechanisms, and the purpose of the study was to characterize miRNAs expression in gastric tissue of patients with cirrhosis and GAVE. Thirteen patients with GAVE and cirrhosis and 35 healthy subjects were recruited. Microarray analysis and comparative microRNA study was done by quantitative polymerase chain reaction (qPCR). The microarray scores were grouped with use of the hierarchical clusterization analysis and miRNA target prediction was done with TargetScan 6.2 algorithm and Gene Ontology analysis (DIANA-miRPath). Concentration of miR-3677 in GAVE-affected mucosa was higher by 72% in comparison with GAVE-free mucosa of patients with cirrhosis (33.7 vs. 35.6 PCR cycles; p < .001) and by 45% in comparison with normal mucosa (33.7 vs. 34.9 PCR cycles; p < .05). According to Gene Ontology analysis miR-3677 was related to angiopoietin-like protein 4 (ANGPTL4) gene. GAVE in liver cirrhosis is associated with increased expression of miR-3667 that may be linked with ANGPTL4 gene. Show less

Different breeds of pigs vary greatly in their propensity for adiposity. Gut microbiota is known to play an important role in modulating host physiology including fat metabolism. However, the relative contribution of gut microbiota to lipogenic characteristics of pigs remains elusive. In this study, we transplanted fecal microbiota of adult Jinhua and Landrace pigs, two breeds of pigs with distinct lipogenic phenotypes, to antibiotic-treated mice. Our results indicated that, 4 weeks after fecal transplantation, the mice receiving Jinhua pigs' "obese" microbiota (JM) exhibited a different intestinal bacterial community structure from those receiving Landrace pigs' "lean" microbiota (LM). Notably, an elevated ratio of Firmicutes to Bacteroidetes and a significant diminishment of Show less

Bacterial infection and inflammation of the testis impairs fertility, yet an understanding of inflammatory responses of the testis is incomplete. We are interested in identifying gene pathways involved in the detection and clearance of infectious microbes in the male reproductive tract. In previous studies in our lab focused on hypoxia-responsive genes of the testis, preliminary experiments suggested that genes classically categorized as hypoxia genes are also activated during antimicrobial responses. The purpose of this study was to identify hypoxia and inflammatory gene pathways that contribute to antimicrobial protection of the testis and to consider possible cross-talk and interactions between these pathways. Inflammation was induced in Sprague-Dawley rats using In LPS-treated rats, HIF-1α protein increased with no change in Testicular HIF-1α is up-regulated following LPS-induced inflammation. In contrast to other tissues, in which HIF-1α is up-regulated through transcriptional activation via NF-κB, we conclude that HIF-1α in the testis is not up-regulated through an increase in Show less

This study was design to investigate preventive function of Tongxinluo (TXL) capsule on micro vascular function and endothelial survival in rats model of intestine ischemia/reperfusion (I/R) injury. We randomly divided fifty male Sprague-Dawley rats into Sham group, I/R group, TXL0.4+I/R group, TXL0.8+I/R group, TXL1.6+I/R group (10 rats each). Rat intestine I/R injury was carried out using a model of acute superior mesenteric artery occlusion with 30 min ischemia followed by 60 min reperfusion. The distribution of endothelial apoptosis in intestine was determined by CD31+TUNEL immunofluorescent double staining analysis. VE-Cadherin, ANGPTL4, HMGB1 and NF-κB were determined by immunohistochemical analysis. I/R induced massively endothelial cell apoptosis, accompanied with reduced expression of adherens junction protein VE-Cadherin and up regulation of inflammatory mediator HMGB1 and NF-κB. TXL pretreatment groups (TXL0.4+I/R, TXL0.8+I/R and TXL1.6+I/R group) significantly attenuated endothelial cell apoptosis with a dose-dependent effect. TXL pretreatment could maintain the expression of VE-Cadherin and promote the expression of ANGPTL4 which help to maintain endothelial integrity. TXL pretreatment also exert great influence in inhibiting HMGB1 expression and NF-κB expression induced by I/R. It could be concluded from this study that micro vascular dysfunction and endothelial damage play a causal role in rat intestine I/R injury. TXL pretreatment could significantly prevent the I/R induced pathology of endothelial apoptosis, micro vascular integrity disruption and inflammatory reaction. Show less

Increasing evidence suggests that vascular dysfunction in the brain is associated with early stages of Alzheimer's disease. Amyloid-β deposition in the microvasculature of the brain, a process referred to as capillary cerebral amyloid angiopathy (capillary CAA), propagates vascular remodelling, which results in impaired function of the blood-brain barrier, reduced cerebral perfusion and increased hypoxia. While improving vascular function may be an attractive new way to fight capillary CAA, the underlying factors that mediate vascular alterations in Alzheimer's disease and capillary CAA pathogenesis remain largely unknown. Here we provide first evidence that angiopoietin like-4 (ANGPTL4), a hypoxia-induced factor, is highly expressed by reactive astrocytes in well characterized post-mortem tissues of patients with capillary CAA. Our in vitro studies reveal that ANGPTL4 is upregulated and secreted by human cortical astrocytes under hypoxic conditions and in turn stimulates endothelial cell migration and sprouting in a 3D spheroid model of human brain endothelial cells. Interestingly, plasma levels of ANGPTL4 are significantly increased in patients with vascular dementia compared to patients with subjective memory complaints. Overall, our data suggest that ANGPTL4 contributes to pathological vascular remodelling in capillary CAA and that detection of ANGPTL4 levels may improve current diagnostics. Ways of counteracting the detrimental effects of ANGPTL4 and thus promoting cerebral vascular function may provide novel treatment regimens to halt the progression of Alzheimer's disease. Show less

Bone marrow-derived mesenchymal stem cells (BMSCs) have been proved to be capable of differentiating into endothelial cells (ECs), however, the differentiation efficiency is rather low. Sonic hedgehog (Shh), an important factor in vascular development and postnatal angiogenesis, exerted promotional effect on new vessel formation in the ischemic animal models. Therefore, the current study aims to investigate whether Shh could induce the endothelial differentiation of BMSCs both The current study over-expressed Shh in BMSCs by lentivirus transduction. Reverse-transcription quantitative polymerase chain reaction (RT-qPCR) analysis was performed to determine the angiogenic factors in both control BMSCs and Shh over-expressed BMSCs. Immunocytochemistry was also conducted to examine the EC markers. Angiogenesis was determined by Shh expression was increased by about 3,000-fold and 5,000-fold at 3 days-transfection and 7 days-transfection, respectively. Patched 1 (Ptch1), the receptor for Shh, had a two-fold increase after transduction. The angiogenic factors such as hepatocyte growth factor (HGF), angiopoietin-1 (Ang-1), insulin-like growth factor 1 (IGF1) and vascular endothelial growth factor A (VEGF-A) had at least a 1.5-fold increase after transduction. Expression of EC-lineage markers, CD31 and VE-cadherin, on Shh-overexpressed BMSCs were increasingly detected by immunocytostaining. Angiogenesis of BMSCs could be efficiently induced by Shh overexpression in the This study demonstrated that Shh could promote endothelial differentiation of BMSCs via VEGF-D. Show less

The aim of this study was to evaluate hypoxia level at various tumor developmental stages and to compare various methods of hypoxia evaluation in pre-clinical CT26 tumor model. Using three methods of hypoxia determination, we evaluated hypoxia levels during CT26 tumor development in BALB/c mice from day 4 till day 19, in 2-3 days intervals. Molecular method was based on the analysis of selected genes expression related to hypoxia (HIF1A, ANGPTL4, TGFB1, VEGFA, ERBB3, CA9) or specific for inflammation in hypoxic sites (CCL2, CCL5) at various time points after CT26 cancer cells inoculation. Imaging methods of hypoxia evaluation included: positron-emission tomography (PET) imaging using [18F]fluoromisonidazole ([18F]FMISO) and a fluorescence microscope imaging of pimonidazole (PIMO)-positive tumor areas at various time points. Our results showed that tumor hypoxia at molecular level was relatively high at early stage of tumor development as reflected by initially high HIF1A and VEGFA expression levels and their subsequent decrease. However, imaging methods (both PET and fluorescence microscopy) showed that hypoxia increased till day 14 of tumor development. Additionally, necrotic regions dominated the tumor tissue at later stages of development, decreasing the number of hypoxic areas and completely eliminating normoxic regions (observed by PET). These results showed that molecular methods of hypoxia determination are more sensitive to show changes undergoing at cellular level, however in order to measure and visualize hypoxia in the whole organ, especially at later stages of tumor development, PET is the preferred tool. Furthermore we concluded, that during development of tumor, two peaks of hypoxia occur. Show less

Alzheimer's disease (AD) is an age-related neurodegenerative pathology associated with accumulation of DNA damage. Inflammation and cell cycle alterations seem to be implicated in the pathogenesis of AD, although the molecular mechanisms have not been thoroughly elucidated to date. The aim of the present study was to evaluate whether peripheral blood mononuclear cells (PBMCs) of AD patients display alterations in gene expression profiles, focusing on finding markers that might improve the diagnosis of AD. Blood samples were collected from 22 AD patients and 13 healthy individuals to perform genome-wide mRNA expression. We found 593 differentially expressed genes in AD compared to controls, from which 428 were upregulated, and 165 were downregulated. By performing a gene set enrichment analysis, we observed pathways involved in inflammation, DNA damage response, cell cycle, and neuronal processes. Moreover, functional annotation analyses indicated that differentially expressed genes are strongly related to pathways associated with the cell cycle and the immune system. The results were compared with those of an independent study on hippocampus samples, and a number of genes in common between both studies were identified as potential peripheral biomarkers for AD, including DUSP1, FOS, SLC7A2, RGS1, GFAP, CCL2, ANGPTL4, and SSPN. Taken together, our results demonstrate that PBMCs of AD patients do present alterations in gene expression profiles, and these results are comparable to those previously reported in the literature for AD neurons, supporting the hypothesis that blood peripheral mononuclear cells express molecular changes that occur in the neurons of AD patients. Show less

Cholangiocarcinoma (CCA) is the most common biliary tract malignancy, with a low survival rate and limited treatment options. Long non-coding RNAs (lncRNAs) have recently been verified to have significant regulatory functions in many kinds of human cancers. It was discovered in this study that the lncRNA PVT1, whose expression is significantly elevated in CCA, could be a molecular marker of CCA. Experiments indicated that PVT1 knockdown greatly inhibited cell migration and proliferation in vitro and in vivo. According to RNA sequencing (RNA-seq) analysis, PVT1 knockdown dramatically influenced target genes associated with cell angiogenesis, cell proliferation, and the apoptotic process. RNA immunoprecipitation (RIP) analysis demonstrated that, by binding to epigenetic modification complexes (PRC2), PVT1 could adjust the histone methylation of the promoter of ANGPTL4 (angiopoietin-like 4) and, thus, promote cell growth, migration, and apoptosis progression. The data verified the significant functions of PVT1 in CCA oncogenesis, and they suggested that PVT1 could be a target for CCA intervention. Show less

Immortal hepatocyte cell lines are widely used to elucidate insulin-dependent signalling pathways and regulation of hepatic metabolism, although the often tumorigenic origin might not represent the metabolic state of healthy hepatocytes. We aimed to investigate if murine cell line AML12 and human cell line THLE-2, which are derived from healthy liver cells, are comparable to hepatoma cell line HepG2 for studying acute insulin signalling and expression of gluconeogenic enzymes and hepatokines. Insulin responsiveness of AML12 and THLE-2 cells was impaired when cells were cultured in the recommended growth medium, but comparable with HepG2 cells by using insulin-deficient medium. THLE-2 cells showed low abundance of insulin receptor, while protein levels in HepG2 and AML12 were comparable. AML12 and THLE-2 cells showed only low or non-detectable transcript levels of Show less

Objective- SGLT2 (sodium-glucose cotransporter 2) inhibition in humans leads to increased levels of LDL (low-density lipoprotein) cholesterol and decreased levels of plasma triglyceride. Recent studies, however, have shown this therapy to lower cardiovascular mortality. In this study, we aimed to determine how SGLT2 inhibition alters circulating lipoproteins. Approach and Results- We used a mouse model expressing human CETP (cholesteryl ester transfer protein) and human ApoB100 (apolipoprotein B100) to determine how SGLT2 inhibition alters plasma lipoprotein metabolism. The mice were fed a high-fat diet and then were made partially insulin deficient using streptozotocin. SGLT2 was inhibited using a specific antisense oligonucleotide or canagliflozin, a clinically available oral SGLT2 inhibitor. Inhibition of SGLT2 increased circulating levels of LDL cholesterol and reduced plasma triglyceride levels. SGLT2 inhibition was associated with increased LpL (lipoprotein lipase) activity in the postheparin plasma, decreased postprandial lipemia, and faster clearance of radiolabeled VLDL (very-LDL) from circulation. Additionally, SGLT2 inhibition delayed turnover of labeled LDL from circulation. Conclusions- Our studies in diabetic CETP-ApoB100 transgenic mice recapitulate many of the changes in circulating lipids found with SGLT2 inhibition therapy in humans and suggest that the increased LDL cholesterol found with this therapy is because of reduced clearance of LDL from the circulation and greater lipolysis of triglyceride-rich lipoproteins. Most prominent effects of SGLT2 inhibition in the current mouse model were seen with antisense oligonucleotides-mediated knockdown of SGLT2. Show less

Overcoming multidrug resistance has always been a major challenge in cancer treatment. Recent evidence suggested epithelial-mesenchymal transition plays a role in MDR, but the mechanism behind this link remains unclear. We found that the expression of multiple ABC transporters was elevated in concordance with an increased drug efflux in cancer cells during EMT. The metastasis-related angiopoietin-like 4 (ANGPTL4) elevates cellular ATP to transcriptionally upregulate ABC transporters expression via the Myc and NF-κB signaling pathways. ANGPTL4 deficiency reduced IC Show less

Coronary artery disease is the most common cause of death globally and is linked to a number of risk factors including serum low density lipoprotein, high density lipoprotein, triglycerides and lipoprotein(a). Recently two proteins, angiopoietin-like protein 3 and 4, have emerged from genetic studies as being factors that significantly modulate plasma triglyceride levels and coronary artery disease. The exact function and mechanism of action of both proteins remains to be elucidated, however, mutations in these proteins results in up to 34% reduction in coronary artery disease and inhibition of function results in reduced plasma triglyceride levels. Here we report the crystal structures of the fibrinogen-like domains of both proteins. These structures offer new insights into the reported loss of function mutations, the mechanisms of action of the proteins and open up the possibility for the rational design of low molecular weight inhibitors for intervention in coronary artery disease. Show less

Pharmacological enhancers of lipoprotein lipase (LPL) are in preclinical or early clinical development for cardiovascular prevention. Studying whether these agents will reduce cardiovascular events or diabetes risk when added to existing lipid-lowering drugs would require large outcome trials. Human genetics studies can help prioritize or deprioritize these resource-demanding endeavors. To investigate the independent and combined associations of genetically determined differences in LPL-mediated lipolysis and low-density lipoprotein cholesterol (LDL-C) metabolism with risk of coronary disease and diabetes. In this genetic association study, individual-level genetic data from 392 220 participants from 2 population-based cohort studies and 1 case-cohort study conducted in Europe were included. Data were collected from January 1991 to July 2018, and data were analyzed from July 2014 to July 2018. Six conditionally independent triglyceride-lowering alleles in LPL, the p.Glu40Lys variant in ANGPTL4, rare loss-of-function variants in ANGPTL3, and LDL-C-lowering polymorphisms at 58 independent genomic regions, including HMGCR, NPC1L1, and PCSK9. Odds ratio for coronary artery disease and type 2 diabetes. Of the 392 220 participants included, 211 915 (54.0%) were female, and the mean (SD) age was 57 (8) years. Triglyceride-lowering alleles in LPL were associated with protection from coronary disease (approximately 40% lower odds per SD of genetically lower triglycerides) and type 2 diabetes (approximately 30% lower odds) in people above or below the median of the population distribution of LDL-C-lowering alleles at 58 independent genomic regions, HMGCR, NPC1L1, or PCSK9. Associations with lower risk were consistent in quintiles of the distribution of LDL-C-lowering alleles and 2 × 2 factorial genetic analyses. The 40Lys variant in ANGPTL4 was associated with protection from coronary disease and type 2 diabetes in groups with genetically higher or lower LDL-C. For a genetic difference of 0.23 SDs in LDL-C, ANGPTL3 loss-of-function variants, which also have beneficial associations with LPL lipolysis, were associated with greater protection against coronary disease than other LDL-C-lowering genetic mechanisms (ANGPTL3 loss-of-function variants: odds ratio, 0.66; 95% CI, 0.52-0.83; 58 LDL-C-lowering variants: odds ratio, 0.90; 95% CI, 0.89-0.91; P for heterogeneity = .009). Triglyceride-lowering alleles in the LPL pathway are associated with lower risk of coronary disease and type 2 diabetes independently of LDL-C-lowering genetic mechanisms. These findings provide human genetics evidence to support the development of agents that enhance LPL-mediated lipolysis for further clinical benefit in addition to LDL-C-lowering therapy. Show less

This study aimed to assess the association between the angiopoietin-like protein 4 gene ( Genotypes of the The rs2967605 CT/TT genotypes were associated with a decreased risk of CAD (adjusted OR = 0.68, 95% CI = 0.47-0.99, The observed associations suggest that the Show less

The Million Veteran Program (MVP) was established in 2011 as a national research initiative to determine how genetic variation influences the health of US military veterans. Here we genotyped 312,571 MVP participants using a custom biobank array and linked the genetic data to laboratory and clinical phenotypes extracted from electronic health records covering a median of 10.0 years of follow-up. Among 297,626 veterans with at least one blood lipid measurement, including 57,332 black and 24,743 Hispanic participants, we tested up to around 32 million variants for association with lipid levels and identified 118 novel genome-wide significant loci after meta-analysis with data from the Global Lipids Genetics Consortium (total n > 600,000). Through a focus on mutations predicted to result in a loss of gene function and a phenome-wide association study, we propose novel indications for pharmaceutical inhibitors targeting PCSK9 (abdominal aortic aneurysm), ANGPTL4 (type 2 diabetes) and PDE3B (triglycerides and coronary disease). Show less

Clear cell renal cell carcinoma (ccRCC) is the most frequent type of renal cell carcinoma (RCC). The present study aimed to examine prognostic markers and construct a prognostic prediction system for ccRCC. The mRNA sequencing data of ccRCC was downloaded from The Cancer Genome Atlas (TCGA) database, and the GSE40435 dataset was obtained from the Gene Expression Omnibus database. Using the Limma package, the differentially expressed genes (DEGs) in the TCGA dataset and GSE40435 dataset were obtained, respectively, and the overlapped DEGs were selected. Subsequently, Cox regression analysis was applied for screening prognosis‑associated genes. Following visualization of the co‑expression network using Cytoscape software, the network modules were examined using the GraphWeb tool. Functional annotation for genes in the network was performed using the clusterProfiler package. Finally, a prognostic prediction system was constructed through Bayes discriminant analysis and confirmed with the GSE29609 validation dataset. The results revealed a total of 263 overlapped DEGs and 161 prognosis‑associated genes. Following construction of the co‑expression network, 16 functional terms and three pathways were obtained for genes in the network. In addition, red, yellow (involving chemokine ligand 10 (CXCL10), CD27 molecule (CD27) and runt‑related transcription factor 3 (RUNX3)], green (involving angiopoietin‑like 4 (ANGPTL4), stanniocalcin 2 (STC2), and sperm associated antigen 4 (SPAG4)], and cyan modules were extracted from the co‑expression network. Additionally, the prognostic prediction system involving 44 signature genes, including ANGPTL4, STC2, CXCL10, SPAG4, CD27, matrix metalloproteinase (MMP9) and RUNX3, was identified and confirmed. In conclusion, the 44‑gene prognostic prediction system involving ANGPTL4, STC2, CXCL10, SPAG4, CD27, MMP9 and RUNX3 may be utilized for predicting the prognosis of patients with ccRCC. Show less

To explore ANGPTL4 expressions in patients with gestational diabetes mellitus (GDM) and its underlying mechanism. We first detected serum expressions of ANGPTL4 in GDM patients and healthy pregnancies. Subsequently, effects of ANGPTL4 knockdown on apoptosis, proliferation, and cell cycle in 3T3-L1 cells were determined, respectively. Effects of ANGPTL4 on glucose uptake and adipocyte differentiation were also evaluated, respectively. The cytokine secretion in adipocytes transfected with sh-ANGPTL4 was detected by quantitative Reverse Transcriptase-Polymerase Chain Reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA). Furthermore, effects of ANGPTL4 knockdown on NF-kB and Akt pathway were detected by Western blot. ANGPTL4 was down-regulated in serum of GDM patients. In vitro experiments suggested that down-regulated ANGPTL4 inhibited apoptosis and promoted proliferation of 3T3-L1 cells. Meanwhile, down-regulated ANGPTL4 significantly inhibited glucose uptake and Akt pathway. However, ANGPTL4 expression did not affect cell cycle and adipocyte differentiation. Detection of inflammatory cytokines suggested that down-regulated ANGPTL4 resulted in increased expressions of inflammatory cytokines and activation of NF-kB pathway. ANGPTL4 is down-regulated in GDM and may participate in the GDM development by promoting insulin resistance and secretion of inflammatory cytokines. Show less

The aim of this study was to investigate the role and expression of a novel angiogenic factor (angiopoietin-like 4, ANGPTL4) in tibial growth plates of broiler chickens exposed to high-altitude hypoxia. One-day-old healthy broiler chickens (n = 120) were transported from lowland to a high-altitude hypoxic region (nearly 3,000 m above sea level) and were reared under hypoxic- (natural lower oxygen content) and normoxic conditions (nearly 21% oxygen content) for 14 days. The effect of hypoxia on angiogenesis in the tibial growth plates and hypoxia-inducible factor (HIF)-1α and ANGPTL4 expressions were determined by histological examination, quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), western blot and enzyme-linked immunosorbent assay (ELISA) techniques. The increase in vascular distribution to the hypertrophic chondrocyte zone of tibial growth plates contributed to promoting growth and development of the tibia under hypoxic conditions, which was highly correlated with the upregulation of ANGPTL4 at both the mRNA and protein levels together with activation of HIF-1α under hypoxic conditions. These findings demonstrate that angiogenic factor ANGPTL4 upregulation is involved in tibial growth plate angiogenesis to promote the development of the tibia in broiler chickens under hypoxic conditions. They also suggest that ANGPTL4 may serve as a new molecular therapeutic target for ameliorating tibial dyschondroplasia chicken bone vascularization. Show less

Angiopoietin-like protein 4 (ANGPTL4) is a circulating protein involved in the regulation of adipose tissue metabolism. However, its role in obesity and pregnancy is unknown. To evaluate the relationship between gestational weight gain (GWG) and circulating concentrations of ANGPTL4 in pregnant women with overweight and obesity, weight gain and fasting maternal blood samples of thirty-one pregnant women was drawn at 15, 24 and 32 weeks of gestation. ANGPTL4 concentrations continuously rose throughout gestation, whereas VEGF and leptin did not show the same trend. NEFA and glycerol concentrations remained stable during pregnancy. In contrast, total concentrations of saturated, monounsaturated and n-6 fatty acids, but not n-3 fatty acids, increased with pregnancy. In multiple regression analysis, the increase in plasma ANGPTL4 and decrease in linoleic acid concentrations were the most significant predictors of GWG, although only ANGPTL4 was significantly associated with the weight gain from early pregnancy (area under the ROC curve was 0.80 p < 0.01(95% CI 0.61-0.99)). In conclusion, in pregnant women with overweight and obesity, an increase in plasma ANGPTL4 concentrations throughout pregnancy is positively associated with GWG and could be used as an early marker of increased susceptibility to excess gestational weight gain. Show less

During peripartum period, dairy cows are highly susceptible to energy metabolism disorders such as fatty liver and ketosis. Angiopoietin-like protein 4 (ANGPTL4) and fibroblast growth factor 21 (FGF21), known as hepatokines, play important roles in lipid metabolism. The purposes of our study were to evaluate variations of serum ANGPTL4 and FGF21 concentrations in periparturient dairy cows and changes in these serum analyte concentrations of energy-related metabolic disorders in early lactation dairy cows. This study was divided into two experiments. Experiment I: Blood parameters were measured in healthy periparturient Holstein cows from 4 wk antepartum to 4 wk postpartum (n = 219). In this experiment, weekly blood samples were obtained from 4 wk before the expected calving date through 4 wk after calving. Experiment II: Blood parameters were measured in healthy cows (n = 30) and cows with clinical ketosis (n = 29) and fatty liver (n = 25) within the first 4 wk of lactation. In the present study, all blood samples were collected from the coccygeal vein in the early morning before feeding. Serum ANGPTL4 and FGF21 concentrations peaked at parturition, and declined rapidly over the following 2 wk Serum ANGPTL4 and FGF21 concentrations were positively correlated with serum non-esterified fatty acids (NEFA) concentration (r = 0.856, P = 003; r = 0.848, P = 0.004, respectively). Cows with clinical ketosis and fatty liver had significantly higher serum ANGPTL4 and FGF21 concentrations than healthy cows (P < 0.01). Serum ANGPTL4 and FGF21 concentrations were elevated during peripartum period, suggesting that energy balance changes that were associated with parturition contributed significantly to these effects. Although FGF21 and ANGPTL4 could play important roles in the adaptation of energy metabolism, they may be involved in the pathological processes of energy metabolism disorders of dairy cows in the peripartum period. Show less

Enzyme modified non-oxidative LDL (ELDL) is effectively taken up by vascular smooth muscle cells (SMC) and mediates transition into foam cells and produces phenotypic changes in SMC function. Our data show that incubation of human coronary artery SMC (HCASMC) with low concentration of ELDL (10 μg/ml) results in significantly enhanced foam cell formation compared to oxidized LDL (200 μg/ml; p < 0.01) or native LDL (200 μg/ml; p < 0.01). Bioinformatic network analysis identified activation of p38 MAPK, NFkB, ERK as top canonical pathways relevant for biological processes linked to cell migration and osteoblastic differentiation in ELDL-treated cells. Functional studies confirmed increased migration of HCASMC upon stimulation with ELDL (10 μg/ml) or Angiopoietin like protein 4, (ANGPTL4, 5 μg/ml), and gain in osteoblastic gene profile with significant increase in mRNA levels for DMP-1, ALPL, RUNX2, OPN/SPP1, osterix/SP7, BMP and reduction in mRNA for MGP and ENPP1. Enhanced calcification of HCASMC by ELDL was demonstrated by Alizarin Red staining. In summary, ELDL is highly potent in inducing foam cells in HCASMC and mediates a phenotypic switch with enhanced migration and osteoblastic gene profile. These results point to the potential of ELDL to induce migratory and osteoblastic effects in human smooth muscle cells with potential implications for migration and calcification of SMCs in human atherosclerosis. Show less

The present study examined and compared the effects of low- and high-molecular weight (MW) chitosan, a nutraceutical, on lipid metabolism in the intestine and liver of high-fat (HF) diet-fed rats. High-MW chitosan as well as low-MW chitosan decreased liver weight, elongated the small intestine, improved the dysregulation of blood lipids and liver fat accumulation, and increased fecal lipid excretion in rats fed with HF diets. Supplementation of both high- and low-MW chitosan markedly inhibited the suppressed phosphorylated adenosine monophosphate (AMP)-activated protein kinase-α (AMPKα) and peroxisome proliferator-activated receptor-α (PPARα) protein expressions, and the increased lipogenesis/cholesterogenesis-associated protein expressions [peroxisome proliferator-activated receptor-γ (PPARγ), sterol regulatory element binding protein-1c and -2 (SREBP1c and SREBP2)] and the suppressed apolipoprotein E (ApoE) and microsomal triglyceride transfer protein (MTTP) protein expressions in the livers of rats fed with HF diets. Supplementation with both a low- and high-MW chitosan could also suppress the increased MTTP protein expression and the decreased angiopoietin-like protein-4 (Angptl4) expression in the intestines of rats fed with HF diets. In comparison between low- and high-MW chitosan, high-MW chitosan exhibits a higher efficiency than low-MW chitosan on the inhibition of intestinal lipid absorption and an increase of hepatic fatty acid oxidation, which can improve liver lipid biosynthesis and accumulation. Show less