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Rhesus theta defensin-1 (RTD-1), a macrocyclic immunomodulatory host defense peptide from Old World monkeys, is therapeutic in pristane-induced arthritis (PIA) in rats, a model of rheumatoid arthritis (RA). RNA-sequence (RNA-Seq) analysis was used to interrogate the changes in gene expression in PIA rats, which identified 617 differentially expressed genes (DEGs) in PIA synovial tissue of diseased rats. Upstream regulator analysis showed upregulation of gene expression pathways regulated by TNF, IL1B, IL6, proinflammatory cytokines, and matrix metalloproteases (MMPs) involved in RA. In contrast, ligand-dependent nuclear receptors like the liver X-receptors NR1H2 and NR1H3 and peroxisome proliferator-activated receptor gamma (PPARG) were downregulated in arthritic synovia. Daily RTD-1 treatment of PIA rats for 1-5 days following disease presentation modulated 340 of the 617 disease genes, and synovial gene expression in PIA rats treated 5 days with RTD-1 closely resembled the gene signature of naive synovium. Systemic RTD-1 inhibited proinflammatory upstream regulators such as TNF, IL1, and IL6 and activated antiarthritic ligand-dependent nuclear receptor pathways, including PPARG, NR1H2, and NR1H3, that were suppressed in untreated PIA rats. RTD-1 also inhibited proinflammatory responses in IL-1β-stimulated human RA fibroblast-like synoviocytes (FLS) in vitro and diminished expression of human orthologs of disease genes that are induced in rat PIA synovium. Thus, the antiarthritic mechanisms of systemic RTD-1 include homeostatic regulation of arthritogenic gene networks in a manner that correlates temporally with clinical resolution of rat PIA. Show less

There is scarce data on CASR associations with dyslipidemia. We investigated in hemodialysis (HD) patients whether CASR single nucleotide polymorphisms (SNPs) rs7652589 and rs1801725 have associations with dyslipidemia and show epistatic interactions with SNPs of the energy homeostasis-associated gene (ENHO), retinoid X receptor α gene (RXRA), and liver X receptor α gene (LXRA). The study included 1208 HD subjects. For diagnosis of dyslipidemia, both K/DOQI criteria and atherogenic index ≥3.8 were used. CASR rs1801725 was genotyped by TaqMan SNP Genotyping Assay, other SNPs - by high-resolution melting curve analysis or polymerase chain reaction-restriction fragment length polymorphism, as appropriate. Relative transcript levels of CASR, ENHO, RXRA, and LXRA were measured in peripheral blood mononuclear cells. The occurrence of dyslipidemic phenotypes concerning tested polymorphisms was compared using models of inheritance. Haplotypes were estimated using the Haploview 4.2 software. Epistatic interactions between tested SNPs were analyzed using the logistic regression and epistasis option in the PLINK software. Rs7652589 indicated a greater probability of atherogenic dyslipidemia in the dominant inheritance model (OR 1.4, 95%CI 1.0-2.0, P = 0.026), principally because of increased triglyceride (TG) levels. The rs1801725 variant allele was associated with a decreased probability of dyslipidemia characterized by non-HDL-cholesterol ≥130 mg/dL and TG ≥200 mg/dL (OR 0.6, 0.4-0.9, P = 0.012). There were no epistatic interactions between CASR and RXRA, LXRA, and ENHO regarding dyslipidemia. Both rs7652589 and rs1801725 SNPs were not in linkage disequilibrium (D' = 0.091, r CASR polymorphisms (rs7652589, rs1801725) are associated with dyslipidemia in HD patients. CASR correlates with RXRA, LXRA, and ENHO at the transcript level. Further investigations may elucidate whether other CASR SNPs contribute to associations shown in this study. Show less

Liver X receptors (LXRs) are ligand-dependent transcription factors acting as 'cholesterol sensors' to regulate lipid homeostasis in cells. The two isoforms, LXRα (NR1H3) and LXRβ (NR1H2), are differentially expressed, with the former expressed predominantly in metabolically active tissues and the latter more ubiquitously. Both are activated by oxidised cholesterol metabolites, endogenously produced oxysterols. LXRs have important roles in lipid metabolism and inflammation, plus a number of newly emerging roles. They are implicated in regulating lipid balance in normal male reproductive function and may provide a link between male infertility and lipid disorders and/or obesity. Studies from Lxr knockout mouse models provide compelling evidence to support this. More recently published data suggest distinct and overlapping roles of the LXR isoforms in the testis and recent evidence of a role for LXRs in human male fertility. This review summarises the current literature and explores the likely link between LXR, lipid metabolism and male fertility as part of a special issue on Liver X receptors in International Journal of Molecular Sciences. Show less

Prostate cancer (PCa) incidence has been dramatically increasing these last years in westernized countries. Though localized PCa is usually treated by radical prostatectomy, androgen deprivation therapy is preferred in locally advanced disease in combination with chemotherapy. Unfortunately, PCa goes into a castration-resistant state in the vast majority of the cases, leading to questions about the molecular mechanisms involving the steroids and their respective nuclear receptors in this relapse. Interestingly, liver X receptors (LXRα/NR1H3 and LXRβ/NR1H2) have emerged as new actors in prostate physiology, beyond their historical roles of cholesterol sensors. More importantly LXRs have been proposed to be good pharmacological targets in PCa. This rational has been based on numerous experiments performed in PCa cell lines and genetic animal models pointing out that using selective liver X receptor modulators (SLiMs) could actually be a good complementary therapy in patients with a castration resistant PCa. Hence, this review is focused on the interaction among the androgen receptors (AR/NR3C4), estrogen receptors (ERα/NR3A1 and ERβ/NR3A2), and LXRs in prostate homeostasis and their putative pharmacological modulations in parallel to the patients' support. Show less

Abruptio placentae is a complex multifactorial disease that is associated with maternal and neonatal death and morbidity. Abruptio placentae's high recurrence rate, high prevalence of heritable thrombophilia among women with abruptio placentae, and aggregation of cases in families of women with the disease support the possibility of a genetic predisposition. Previous genome-wide and candidate gene association studies have identified single nucleotide polymorphisms in mitochondrial biogenesis and oxidative phosphorylation genes that potentially are associated with abruptio placentae risk. Perturbations in mitochondrial biogenesis and oxidative phosphorylation, which results in mitochondrial dysfunction, can lead to the impairment of differentiation and invasion of the trophoblast and to several obstetrics complications that include abruptio placentae. The purpose of this study was to determine whether the results of a candidate genetic association study that indicated a link between DNA variants (implicated in mitochondrial biogenesis and oxidative phosphorylation) and abruptio placentae could be replicated. The study was conducted among participants (507 abruptio placentae cases and 1090 control subjects) of the Placental Abruption Genetic Epidemiology study. Weighted genetic risk scores were calculated with the use of abruptio placentae risk-increasing alleles of 11 single nucleotide polymorphisms in 9 mitochondrial biogenesis and oxidative phosphorylation genes (CAMK2B, NR1H3, PPARG, PRKCA, THRB, COX5A, NDUFA10, NDUFA12, and NDUFC2), which previously was reported in the Peruvian Abruptio Placentae Epidemiology study, a study with similar design and study population to the Placental Abruption Genetic Epidemiology study. Logistic regression models were fit to examine associations of weighted genetic risk scores (quartile 1, <25th percentile; quartile 2, 25-50th percentile; quartile 3, 50-70th percentile, and quartile 4, >75th percentile) with risk of abruptio placentae, adjusted for population admixture (the first 4 principal components), maternal age, infant sex, and preeclampsia. The weighted genetic risk score was also modeled as a continuous predictor. To assess potential effect modification, analyses were repeated among strata that were defined by preeclampsia status, maternal age (≥35 vs 18-34 years), and infant sex. Abruptio placentae cases were more likely to have preeclampsia, shorter gestational age, and lower infant birthweight. Participants in quartile 2 (score, 12.6-13.8), quartile 3 (score, 13.9-15.0) and quartile 4 (score, ≥15.1) had a genetic risk score of 1.45-fold (95% confidence interval, 1.04-2.02; P=.03), a 1.42-fold (95% confidence interval, 1.02-1.98; P=.04), and a 1.75-fold (95% confidence interval, 1.27-2.42; P=7.0E-04) higher odds of abruptio placentae, respectively, compared with those in quartile 1 (score,<12.6; P-for trend=.0003). The risk of abruptio placentae was 1.12-fold (95% confidence interval, 1.05-1.19; P=3.0×10 In this study, we replicated previous findings and provide strong evidence for DNA variants that encode for genes that are involved in mitochondrial biogenesis and oxidative phosphorylation pathways, which confers risk for abruptio placentae. These results shed light on the mechanisms that implicate DNA variants that encode for proteins in mitochondrial function that are responsible for abruptio placentae risk. Therapeutic efforts to reduce risk of abruptio placentae can be enhanced by improved biologic understanding of maternal mitochondrial biogenesis/oxidative phosphorylation pathways and identification of women who would be at high risk for abruptio placentae. 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 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

Fructose consumption from added sugars correlates with the epidemic rise in obesity, metabolic syndrome and cardiovascular diseases. However, consumption of beverages containing fructose is allowed during gestation. We have investigated whether maternal fructose intake produces subsequent changes in cholesterol metabolism of progeny. Carbohydrates were supplied to pregnant rats in drinking water (10% w/v solution) throughout gestation. Adult male and female descendants from fructose-fed, control or glucose-fed mothers were studied. Male offspring from fructose-fed mothers had elevated plasma HDL-cholesterol levels, whereas female progeny from fructose-fed mothers presented lower levels of non-HDL cholesterol vs. the other two groups. Liver X-receptor (LXR), an important regulator of cholesterol metabolism, and its target genes such as scavenger receptor B1, ATP-binding cassette (ABC)G5 and cholesterol 7-alpha hydroxylase showed decreased gene expression in males from fructose-fed mothers and the opposite in the female progeny. Moreover, the expression of a number of LXRα target genes related to lipogenesis paralleled to that for LXRα expression. In accordance with this, LXRα gene promoter methylation was increased in males from fructose-fed mothers and decreased in the corresponding group of females. Surprisingly, plasma folic acid levels, an important methyl-group donor, were augmented in males from fructose-fed mothers and diminished in female offspring. Maternal fructose intake produces a fetal programming that influences, in a gender-dependent manner, the transcription factor LXRα epigenetically, and both hepatic mRNA gene expression and plasma parameters of cholesterol metabolism in adult progeny. Changes in the LXRα promoter methylation might be related to the availability of the methyl donor folate. Show less

We previously showed that complement 3 (C3) is highly expressed in mesenchymal tissues in spontaneously hypertensive rats (SHR). We targeted C3 gene by zinc-finger nuclease (ZFN) gene-editing technology and investigated blood pressure and phenotype in SHR. Blood pressure was measured by tail-cuff and telemetry methods. Histology and expression of liver X receptor α (LXRα), renin, Krüppel-like factor 5 (KLF5), and E-cadherin were evaluated in kidneys. Mesangial cells (MCs) were removed from glomeruli from three strains, and we evaluated the phenotype in vitro. SHR showed the salt-sensitive hypertension that was abolished in C3 knockout (KO) SHR. Proliferation of MCs from SHR was higher than that from Wistar-Kyoto (WKY) rats and showed a synthetic phenotype. Renal injury scores were higher in SHR than in WKY rats and C3 KO SHR. Expression of E-cadherin was lower, and expression of renin was higher in the nephrotubulus from SHR than WKY rats and C3 KO SHR. Expression of C3 α-chain protein and α-smooth muscle actin protein was significantly higher in renal medulla from SHR than from WKY rats. Expression of angiotensinogen, LXRα, renin, and KLF5 mRNA was increased in kidney from SHR compared with C3 KO SHR. Intrarenal angiotensin II levels were significantly higher in kidney from SHR than WKY rats and C3 KO SHR. Urinary epinephrine and norepinephrine excretions were significantly higher in SHR than in WKY rats and C3 KO SHR. These findings showed that increased C3 induces salt-sensitive hypertension with increases in urinary catecholamine excretion and intrarenal activation of the renin-angiotensin system by the dedifferentiation of mesenchymal tissues in kidney from SHR. Show less

Recent evidence indicates that immune cells contribute to the formation of tumor metastases by regulating the pre-metastatic niche. Whether tumor-derived factors involved in primary tumor formation play a role in metastasis formation is poorly characterized. Oxysterols act as endogenous regulators of lipid metabolism through the interaction with the nuclear Liver X Receptors-(LXR)α and LXRβ. In the context of tumor development, they establish a pro-tumor environment by dampening antitumor immune responses, and by recruiting pro-angiogenic and immunosuppressive neutrophils. However, the ability of LXR/oxysterol axis to promote tumor invasion and metastasis by exploiting immune cells, is still up to debate. In this study we provide evidence that oxysterols participate in the primary growth of orthotopically implanted 4T1 breast tumors by establishing a tumor-promoting microenvironment. Furthermore, we show that oxysterols are involved in the metastatic spread of 4T1 breast tumors, since their enzymatic inactivation mediated by the sulfotransferase 2B1b, reduces the number of metastatic cells in the lungs of tumor-bearing mice. Finally, we provide evidence that oxysterols support the metastatic cascade by modifying the lung metastatic niche, particularly allowing the recruitment of tumor-promoting neutrophils. These results identify a possible new metastatic pathway to target in order to prevent metastasis formation in breast cancer patients. Show less

Macrophage-derived foam-cell formation plays a crucial role in the development of atherosclerosis, and liver X receptor alpha (LXRα) is a key regulator of lipid metabolism in macrophages. Homocysteine (Hcy) is an independent risk factor of atherosclerosis; however, the regulation of lipid metabolism and role of LXRα induced by Hcy in macrophages is still unknown. The present study aimed to investigate the potential role of Hcy in disordered lipid metabolism and atherosclerotic lesions, especially the effects of Hcy on cholesterol efflux in macrophages and the possible mechanisms. In vitro, lipid accumulation and cholesterol efflux were evaluated in THP-1 macrophages with Hcy intervention. Real-time quantitative PCR and western blot analyses were used to assess mRNA and protein levels. In vivo, atherosclerotic lesions and lipid profiles were evaluated by methionine diet-induced hyperhomocysteinemia (HHcy) in ApoE Hcy promoted lipid accumulation and inhibited cholesterol efflux in THP-1 macrophages. HHcy mice showed increased lesion area and lipid accumulation in plaque. Both studies in vitro and in vivo showed decreased expression of ATP binding cassette transporter A1 (ABCA1) and G1 (ABCG1). T0901317 treatment increased ABCA1 and ABCG1 levels; reversed macrophage-derived foam-cell formation in THP-1 macrophages and reduced atherosclerotic lesions in ApoE Inhibition of LXRα-mediated ABCA1/ABCG1-dependent cholesterol efflux from macrophages is a novel mechanism in Hcy-accelerated atherosclerosis. Show less

The energy homeostasis-associated gene (ENHO), retinoid X receptor alpha gene (RXRA), and liver X receptor alpha gene (LXRA) are involved in adipogenic/lipogenic regulation. We investigated whether single-nucleotide polymorphisms in these genes (ENHO rs2281997, rs72735260; RXRA rs749759, rs10776909, rs10881578; LXRA rs2279238, rs7120118, rs11039155) are associated with dyslipidaemia, related comorbidities and survival of haemodialysis (HD) patients also tested for T-helper (Th) cell interleukin genes (IL). The study was carried out in 873 HD patients. Dyslipidaemia was diagnosed by the recommendations of the Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines (2003); atherogenic dyslipidaemia was referred to if the TG/HDL cholesterol ratio was equal to or higher than 3.8. Genotyping of ENHO SNPs, LXRA SNPs, and IL12A rs568408 was carried out using HRM analysis. RXRA SNPs, IL12B rs3212227, and IL18 rs360719 were genotyped using PCR-RFLP analysis. The circulating adropin concentration was determined in 126 patients by enzyme-linked immunosorbent assay. Survival probability was analysed using the Kaplan-Meier method in 440 patients followed through 7.5 years. Dyslipidaemia by K/DOQI was diagnosed in 459 patients (91% revealed hyper-LDL- cholesterolaemia), atherogenic dyslipidaemia was diagnosed in 454 patients, and 231 patients were free of dyslipidaemia by both criteria. The variant allele (T) of ENHO rs2281997 was associated with the hyper-LDL cholesterolaemic pattern of dyslipidaemia by K/DOQI. The frequency of atherogenic dyslipidaemia was lower in T-allele bearers than in CC-genotype patients. The rs2281997 T allele was associated with lower cardiovascular mortality in HD patients showing atherogenic dyslipidaemia. ENHO, RXRA, and LXRA showed epistatic interactions in dyslipidaemia. Circulating adropin was lower in atherogenic dyslipidaemia than in non-atherogenic conditions. RXRA rs10776909 was associated with myocardial infarction. Bearers of LXRA rs2279238, rs7120118 or rs11039155 minor alleles showed higher mortality. ENHO SNP positions fell within the same DNase 1 hypersensitivity site expressed in the Th1 cell line. Epistatic interactions occurred between rs2281997 and Th1 IL SNPs (rs360719, rs568408). Atherogenic dyslipidaemia occurs in HD patients in whom ENHO encodes less adropin. ENHO, RXRA, and LXRA SNPs, separately or jointly, are associated with dyslipidaemia, myocardial infarction, and survival in HD patients. Differences in the availability of transcription binding sites may contribute to these associations. Show less

Androgens and androgen receptor (AR, NR3C4) clearly play a crucial role in prostate cancer progression. Besides, the link between metabolic disorders and the risk of developing a prostate cancer has been emerging these last years. Interestingly, "lipid" nuclear receptors such as LXRα/NR1H3 and LXRβ/NR1H2 (as well as FXRα/NR1H4 and SHP/NR0B2) have been described to decrease the lipid metabolism, while AR increases it. Moreover, these former orphan nuclear receptors can regulate androgen levels and modulate AR activity. Thus, it is not surprising to find such receptors involved in the physiology of prostate. This review is focused on the roles of liver X receptors (LXRs), farnesoid X receptor (FXR), and small heterodimeric partner (SHP) in prostate physiology and their capabilities to interfere with the androgen-regulated pathways by modulating the levels of active androgen within the prostate. By the use of prostate cancer cell lines, mice deficient for these nuclear receptors and human tissue libraries, several authors have pointed out the putative possibility to pharmacologically target these receptors. These data open a new field of research for the development of new drugs that could overcome the castration resistance in prostate cancer, a usual phenomenon in patients. Show less

Increasing evidence shows that diabetes causes cardiac dysfunction. We hypothesized that a glucagon-like peptide-1 analogue, liraglutide, would attenuate cardiac dysfunction in diabetic rats. Twenty-four Sprague Dawley (SD) rats were divided into 2 groups fed either a normal diet (normal, n = 6) or a high-fat diet (HFD, n = 18) for 4 weeks. Then, the HFD rats were injected with streptozotocin (STZ) to create a diabetic rat model. Diabetic rats were divided into 3 subgroups receiving vehicle (diabetic, n = 6), a low dose of liraglutide (Llirag, 0.2 mg/kg/day, n = 6) or a high dose of liraglutide (Hlirag, 0.4 mg/kg/day, n = 6). Metabolic parameters, systolic blood pressure, heart rate, left ventricular (LV) function, and whole genome expression of the heart were determined. Diabetic rats developed insulin resistance, increased blood lipid levels and oxidative stress, and impaired LV function, serum adiponectin, NO. Liraglutide improved insulin resistance, serum adiponectin, NO, heart rate and LV function and reduced blood triglyceride, total cholesterol levels and oxidative stress. Moreover, liraglutide increased heart Show less

Reverse cholesterol transport (RCT) is a process that prevents atherosclerosis. Studies showed that exercise training for strengthening cardiac muscle, increasing heart lipid metabolism and its potency against risk factors could protect cardiovascular health. Thus, the present study aims to investigate the effects of high intensity interval training (HIIT) on RCT and its related elements in plasma and tissues (liver and intestine) of rats. Twenty adult male Wistar rats were randomly divided into control (n = 10) and trained (n = 10) groups. The trained group undertook HIIT (90%-95% of VO A higher and significant ABCA1 mRNA was observed in the liver and intestine of trained rats. However, ABCG1 and LXR expressions only increased in the liver following the HIIT. These changes in the expression of the trained rats were accompanied by higher changes in plasma LCAT and HDL levels. The responses of ABCA1, as a key player in plasma HDL biogenesis, are similar in liver and intestine tissues after the HIIT program. However, different responses of ABCG1 and LXR in the liver and intestine tissues of the trained rats confirm the main role of the liver than the intestine in HDL biogenes. Therefore, HIIT modality result in cardiovascular protection by increasing the expression of genes involved in RCT and biogenesis of HDL. Show less

Apolipoprotein A-I (ApoA-I) is the main structural and functional protein component of high-density lipoprotein. ApoA-I has been shown to regulate lipid metabolism and inflammation in macrophages. Recently, we found the moderate expression of endogenous apoA-I in human monocytes and macrophages and showed that pro-inflammatory cytokine tumor necrosis factor α (TNFα) increases apoA-I mRNA and stimulates ApoA-I protein secretion by human monocytes and macrophages. Here, we present data about molecular mechanisms responsible for the TNFα-mediated activation of apoA-I gene in human monocytes and macrophages. This activation depends on JNK and MEK1/2 signaling pathways in human monocytes, whereas inhibition of NFκB, JNK, or p38 blocks an increase of apoA-I gene expression in the macrophages treated with TNFα. Nuclear receptor PPARα is a ligand-dependent regulator of apoA-I gene, whereas LXRs stimulate apoA-I mRNA transcription and ApoA-I protein synthesis and secretion by macrophages. Treatment of human macrophages with PPARα or LXR synthetic ligands as well as knock-down of LXRα, and LXRβ by siRNAs interfered with the TNFα-mediated activation of apoA-I gene in human monocytes and macrophages. At the same time, TNFα differently regulated the levels of PPARα, LXRα, and LXRβ binding to the apoA-I gene promoter in THP-1 cells. Obtained results suggest a novel tissue-specific mechanism of the TNFα-mediated regulation of apoA-I gene in monocytes and macrophages and show that endogenous ApoA-I might be positively regulated in macrophage during inflammation. Show less

Obesity is causally associated with atherosclerosis, and adipose tissue (AT)-derived exosomes may be implicated in the metabolic complications of obesity. However, the precise role of AT-exosomes in atherogenesis remains unclear. We herein aimed to assess the effect of AT-exosomes on macrophage foam cell formation and polarization and subsequent atherosclerosis development. Four types of exosomes isolated from the supernatants of ex vivo subcutaneous AT and visceral AT (VAT) explants that were derived from wild-type mice and high-fat diet (HFD)-induced obese mice were effectively taken up by RAW264.7 macrophages. Both treatment with wild-type VAT exosomes and HFD-VAT exosomes, but not subcutaneous AT exosomes, markedly facilitated macrophage foam cell generation through the downregulation of ATP-binding cassette transporter (ABCA1 and ABCG1)-mediated cholesterol efflux. Decreased expression of liver X receptor-α was also observed. Among the 4 types of exosomes, only HFD-VAT exosomes significantly induced M1 phenotype transition and proinflammatory cytokine (tumor necrosis factor α and interleukin 6) secretion in RAW264.7 macrophages, which was accompanied by increased phosphorylation of NF-κB-p65 but not the cellular expression of NF-κB-p65 or IκB-α. Furthermore, systematic intravenous injection of HFD-VAT exosomes profoundly exacerbated atherosclerosis in hyperlipidemic apolipoprotein E-deficient mice, as indicated by the M1 marker (CD16/32 and inducible nitric oxide synthase)-positive areas and the Oil Red O/Sudan IV-stained area, without affecting the plasma lipid profile and body weight. This study demonstrated a proatherosclerotic role for HFD-VAT exosomes, which is exerted by regulating macrophage foam cell formation and polarization, indicating a novel link between AT and atherosclerosis in the context of obesity. Show less

As the most abundant flavonoid in Ampelopsis grossedentata, the protective effects of dihydromyricetin on atherosclerosis have been well established, yet the detailed mechanisms are not fully understood. The aim of the present study was to examine the effect of dihydromyricetin on lipid accumulation and the underlying molecular mechanisms in macrophages and ApoE Show less

The development of acquired EGFR-TKI therapeutic resistance is still a serious clinical problem in the management of lung adenocarcinoma. Peroxisome proliferator activated receptor gamma (PPARγ) agonists may exhibit anti-tumor activity by transactivating genes which are closely associated with cell proliferation, apoptosis, and differentiation. However, it remains not clear whether efatutazone has similar roles in lung adenocarcinoma cells of gefitinib resistant such as HCC827-GR and PC9-GR. It has been demonstrated by us that efatutazone prominently increased the mRNA and protein expression of PPARγ, liver X receptor alpha (LXRα),as well as ATP binding cassette subfamily A member 1 (ABCA1). In the presence of GW9662 (a specific antagonist of PPARγ) or GGPP (a specific antagonist of LXRα), efatutazone (40 μmol/L) restored the proliferation of both HCC827-GR and PC9-GR cells and obviously inhibited the increased protein and mRNA expression of PPAR-gamma, LXR-alpha, and ABCA1 induced by efatutazone. LXRα knockdown by siRNA (si-LXRα) significantly promoted the HCC827-GR and PC9-GR cells proliferation, whereas incubation efatutazone with si-LXRα restored the proliferation ability compared with the control group. In addition, combination of efatutazone and LXRα agonist T0901317 showed a synergistic therapeutic effect on lung adenocarcinoma cell proliferation and PPAR gamma, LXR A and ABCA1 protein expression. These results indicate that efatutazone could inhibit the cells proliferation of HCC827-GR and PC9-GR through PPARγ/LXRα/ABCA1 pathway, and synergistic therapeutic effect is achieved when combined with T0901317. Show less

Elevated intraocular pressure (IOP) is a significant risk factor for glaucoma, the leading cause of irreversible blindness worldwide. While previous studies have identified numerous genetic variants associated with IOP, these loci only explain a fraction of IOP heritability. Recently established of biobank repositories have resulted in large amounts of data, enabling the identification of the remaining heritability for complex traits. Here, we describe the largest genome-wide association study of IOP to date using participants of European ancestry from the UK Biobank. We identified 671 directly genotyped variants that are significantly associated with IOP (P < 5 × 10-8). In addition to 103 novel loci, the top ranked novel IOP genes are LMX1B, NR1H3, MADD and SEPT9. We replicated these findings in an external population and examined the pleiotropic nature of these loci. These discoveries not only further our understanding of the genetic architecture of IOP, but also shed new light on the biological processes underlying glaucoma. Show less

High-sugar intake and senescence share common deleterious effects, in particular in liver, but combination of these two factors was little studied. Our aims were to examine the effect of a high-sucrose diet in liver of old rats and also the potential benefices of a polyphenol/micronutrient supplementation. Four groups of 22-month-old male rats fed during 5 months with a diet containing either 13 or 62% sucrose, supplemented or not with rutin, vitamin E, A, D, selenium, and zinc were compared. We measured liver macronutrient composition, glycation/oxidative stress, enzyme activities (lipogenesis, β-oxidation, fructokinase), gene expression (enzymes and transcription factors), in vivo protein synthesis rates and plasma parameters. Sucrose induced an increase in plasma and liver lipid content, and a stimulation of liver protein synthesis rates. Gene expression was little changed by sucrose, with lower levels for LXR-α and LXR-β. Polyphenol/micronutrient supplementation tended to limit liver triglyceride infiltration through variations in fatty acid synthase, acyl coA oxidase, and possibly ATP-citrate lyase activities. In conclusion, despite differences in enzymatic regulations, and blunted responses of gene expression, high-sucrose diet was still able to induce a marked increase in liver lipid content in old animals. However, it probably attenuated the positive impact of polyphenol/micronutrients. Show less

Preventing postpartum uterine disease depends on the ability of endometrial cells to tolerate the presence of the bacteria that invade the uterus after parturition. Postpartum uterine disease and endometrial pathology in cattle are most associated with the pathogen Trueperella pyogenes. Trueperella pyogenes secretes a cholesterol-dependent cytolysin, pyolysin, which causes cytolysis by forming pores in the plasma membrane of endometrial stromal cells. The aim of the present study was to identify cell-intrinsic pathways that increase bovine endometrial stromal cell tolerance to pyolysin. Pyolysin caused dose-dependent cytolysis of bovine endometrial stromal cells and leakage of lactate dehydrogenase into supernatants. Cell tolerance to pyolysin was increased by inhibitors that target the mevalonate and cholesterol synthesis pathway, but not the mitogen-activated protein kinase, cell cycle, or metabolic pathways. Cellular cholesterol was reduced and cell tolerance to pyolysin was increased by supplying the mevalonate-derived isoprenoid farnesyl pyrophosphate, or by inhibiting farnesyl-diphosphate farnesyltransferase 1 or geranylgeranyl diphosphate synthase 1 to increase the abundance of farnesyl pyrophosphate. Supplying the mevalonate-derived isoprenoid geranylgeranyl pyrophosphate also increased cell tolerance to pyolysin, but independent of changes in cellular cholesterol. However, geranylgeranyl pyrophosphate inhibits nuclear receptor subfamily 1 group H receptors (NR1H, also known as liver X receptors), and reducing the expression of the genes encoding NR1H3 or NR1H2 increased stromal cell tolerance to pyolysin. In conclusion, mevalonate-derived isoprenoids increased bovine endometrial stromal cell tolerance to pyolysin, which was associated with reducing cellular cholesterol and inhibiting NR1H receptors. Show less

The liver X receptors (LXRs; α/β) are nuclear receptors known to regulate cholesterol homeostasis and the production of select hematopoietic populations. The objective of this study was to determine the importance of LXRs and a high-fat high-cholesterol diet on global hematopoiesis, with special emphasis on endothelial progenitor cells (EPCs), a vasoreparative cell type that is derived from bone marrow hematopoietic stem cells. Wild-type and LXR double-knockout ( LXRs are crucial for maintaining the balance of hematopoietic cells in a hypercholesterolemic environment and for mitigating the negative effects of cholesterol on EPC differentiation/secretome changes that promote monocyte-endothelial adhesion. 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 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

A recent study analyzed 2053 multiple sclerosis (MS) cases and 799 healthy controls to investigate whether five genetic variants (rs11039149, rs12221497, rs2279238, rs7120118 and rs7114704) in NR1H3 are associated with MS risk. However this study reported negative results. It is very important that the appropriate samples and approach should be used in replication studies, which may provide the correct interpretation of the results. Here, we evaluated the above findings using large-scale MS genome-wide association studies with a total of 27,148 samples including 9772 MS cases and 17,376 controls, and multiple expression quantitative trait loci datasets. The results suggest that rs7120118 and rs2279238 variants are significantly associated with MS risk, and could significantly regulate NR1H3 expression in kinds of human tissues and cells. In summary, these findings provide important supplementary information about the association between NR1H3 variants and MS risk. Show less

In obesity, elevated insulin causes fatty liver by activating the gene encoding SREBP-1c, a transcription factor that enhances fatty acid synthesis. Two transcription factors, LXRα and C/EBPβ, are necessary but not sufficient for insulin induction of hepatic SREBP-1c mRNA. Here, we show that a third transcription factor, BHLHE40, is required. Immunoprecipitation revealed that BHLHE40 binds to C/EBPβ and LXRα in livers of rats that had fasted and then refed. Hepatic BHLHE40 mRNA rises rapidly when fasted rats are refed and when rat hepatocytes are incubated with insulin. Preventing this rise by gene knockout in mice or siRNAs in hepatocytes reduces the insulin-induced rise in SREBP-1c mRNA. Although BHLHE40 is necessary for insulin induction of SREBP-1c, it is not sufficient as demonstrated by failure of lentiviral BHLHE40 overexpression to increase hepatocyte SREBP-1c mRNA in the absence of insulin. Thus, an additional event is required for insulin to increase SREBP-1c mRNA. Show less

The role of interleukin (IL-)32 in inflammatory conditions is well-established, however, the mechanism behind its role in atherosclerosis remains unexplained. Our group reported a promoter single nucleotide polymorphism in IL-32 associated with higher high-density lipoprotein (HDL) concentrations. We hypothesize that endogenous IL-32 in liver cells, a human monocytic cell line and carotid plaque tissue, can affect atherosclerosis by regulating (HDL) cholesterol homeostasis via expression of cholesterol transporters/mediators. Human primary liver cells were stimulated with recombinant human (rh)TNFα and poly I:C to study the expression of IL-32 and mediators in cholesterol pathways. Additionally, IL-32 was overexpressed in HepG2 cells and overexpressed and silenced in THP-1 cells to study the direct effect of IL-32 on cholesterol transporters expression and function. Stimulation of human primary liver cells resulted in induction of IL-32α, IL-32β and IL-32γ mRNA expression (p < 0.01). A strong correlation between the expression of IL-32γ and ABCA1, ABCG1, LXRα and apoA1 was observed (p < 0.01), and intracellular lipid concentrations were reduced in the presence of endogenous IL-32 (p < 0.05). Finally, IL32γ and ABCA1 mRNA expression was upregulated in carotid plaque tissue and when IL-32 was silenced in THP-1 cells, mRNA expression of ABCA1 was strongly reduced. Regulation of IL-32 in human primary liver cells, HepG2 and THP-1 cells strongly influences the mRNA expression of ABCA1, ABCG1, LXRα and apoA1 and affects intracellular lipid concentrations in the presence of endogenous IL-32. These data, for the first time, show an important role for IL32 in cholesterol homeostasis. Show less

Atherosclerosis is a process of imbalanced lipid metabolism in the vascular walls. The underlying pathology mainly involves the deposition of oxidized lipids in the endothelium and the accumulation of cholesterol in macrophages. Macrophages export excessive cholesterol (cholesterol efflux) through ATP-binding cassette transporter A1 (ABCA1) to counter the progression of atherosclerosis. We synthesized novel chalcone derivatives and assessed their effects and the underlying mechanisms on ABCA1 expression in macrophages. Human THP-1 macrophages were treated with synthetic chalcone derivatives for 24 h. In Western blot and flow cytometry analyses, a chalcone derivative, ( 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 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

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

(1) To investigate the expression patterns of MΦ1 and MΦ2 phenotype markers of peripheral blood monocyte (PBMC)-derived macrophages in atherosclerosis patients and healthy controls, as well as the expression correlation among these genes. (2) To elucidate whether a high level of liver X receptor α (LXRα) expression is associated with anti-inflammatory MΦ2-type polarization. Peripheral blood monocytes (PBMCs) were obtained from 28 patients with carotid artery plaques and 10 normal persons, who did not have carotid artery plaques. M1 and M2 phenotype markers were analyzed after cellular differentiation into macrophages. Human macrophages derived from healthy donors were transfected with plasmid DNA encoding LXRα and control null-plasmids. Gene expression levels were quantified after further differentiation. Three genes (LXRα, CD68, and CD36) were expressed at a significantly lower rate in the atherosclerotic group than normal patients. There were correlations between the expression of LXRα, CD68, and peroxisome proliferator-activated receptor (PPARγ), and between CD163, CD36 and scavenger receptor class A (SRA1). Macrophages over-expressing LXRα exhibited enhanced expression level of MΦ2-type genes and decreased expression level of MΦ1-type genes. PBMCs from healthy persons were predisposed to the MΦ2 differentiation phenotype, which exhibits elevated cholesterol uptake and anti-inflammatory properties. LXRα over-expression polarizes macrophages towards the anti-inflammatory MΦ2 phenotype. Show less