The association of serum total bile acid with non-alcoholic fatty liver disease in Chinese adults: a cross sectional study.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is currently the major cause of chronic liver disease globally. Bile acids (BAs) have emerged as relevant signaling molecules that are associated with NAFLD development. This study was aimed to examine the association of serum total bile acids (TBAs) with NAFLD in a large population of Chinese subjects. METHODS: This cross sectional study recruited 152,336 participants from the Second Xiangya Hospital, China. NAFLD was diagnosed based on the presence of hepatic steatosis on ultrasonography, without significant alcohol consumption and other known causes for chronic liver disease. A multivariate logistic regression model was used to test for the association of serum TBAs with NAFLD, adjusting for conventional risk factors of NAFLD. RESULTS: A total of 27.4% of the participants had NAFLD. Patients with NAFLD had slightly higher TBA levels than those without, 3.4 vs. 3.0 µmol/L (p < 0.001). However, TBA levels were not associated with NAFLD in the multivariate logistic regression model, which adjusted for age, gender and other acknowledged risk factors for NAFLD (OR = 1.00. 95% CI: 1.00-1.00, p = 0.797). CONCLUSIONS: We found that the serum TBA levels were not associated with NAFLD. Future studies in a large population, focusing on serum BA composition may improve the understating of the role of BAs in NAFLD.

The negative effect of ANGPTL8 on HDL-mediated cholesterol efflux capacity.

BACKGROUND: It is well known that angiopoietin-like protein 8 (ANGPTL8) exerts its effects on lipid metabolism through the inhibition of lipoprotein lipase and subsequent elevation of plasma triglyceride. However, it is not clear whether ANGPTL8 could affect lipid metabolism via other pathways. The study was aimed to investigate the effects of ANGPTL8 on the function of high-density lipoprotein (HDL), which plays a protective role in atherosclerosis progression. METHODS: Two hundred and ten subjects were recruited. Plasma ANGPTL8 was measured by enzyme-linked immunosorbent assays. Cholesterol efflux capacity was chosen as the biomarker of HDL function and measured via H3-cholesterol loading THP-1 cell models. RESULTS: ANGPTL8 exhibited no significant difference between CAD group and nonCAD group, but ANGPTL8 in DM group was significantly higher than that in the nonDM group [568.3 (406.2-836.8) vs 458.2 (356.8-755.6), P = 0.023]. Compared to controls, subjects in CAD group and DM group exhibited significantly lower cholesterol efflux capacity [CAD: 14.58 ± 2.06 vs 12.51 ± 2.83%, P < 0.0001; DM: 13.62 ± 2.57 vs 12.34 ± 3.16%, P = 0.0099]. ANGPTL8 was inversely correlated with cholesterol efflux capacity (r = - 0.188, P < 0.01). Regression analysis revealed that plasma ANGPTL8 was an independent contributor to cholesterol efflux capacity (standardized ß = - 0.143, P = 0.023). CONCLUSION: ANGPTL8 presents a negative effect on HDL-mediated cholesterol efflux capacity.

Apolipoprotein CIII may mediate the impacts of angiopoietin-like protein 8 on triglyceride metabolism.

BACKGROUND: Angiopoietin-like protein 8(ANGPTL8) and apolipoprotein CIII (apoCIII) were found to inhibit the activity of lipoprotein lipase (LPL) and disrupt the clearance of triglyceride-rich lipoproteins (TRLs), leading to hypertriglyceridemia. Whether any relationship exists between these two important modulators of triglyceride metabolism has not been reported. Besides, whether ANGPTL8 concentration is altered in the patients with coronary artery disease (CAD) is still unclear. METHODS: A hospital-based case-control study was conducted. Sixty-eight CAD subjects and fifty-two nonCAD controls were recruited. Plasma apoCIII, ANGPTL8 was measured. RESULTS: ANGPTL8 and apoCIII concentration exhibited no significant difference between CAD group and nonCAD group. Both ANGPTL8 and apoCIII were significantly correlated with triglyceride level(r = - 0.243, P = 0.008; r = 0.335, P < 0.001, respectively). Regression analysis revealed that apoCIII was an independent contributor to triglyceride level independent of ANGPTL8 concentration (standardized ß = 0.230, P < 0.01). CONCLUSION: ApoCIII may mediate the effects of ANGPTL8 on triglyceride metabolism.

The emerging role of apolipoprotein C-III: beyond effects on triglyceride metabolism.

Apolipoprotein C-III has been referred to as an important participant in the metabolism of triglyceride-rich lipoproteins, leading to hypertriglyceridemia and thereafter cardiovascular disease. Accumulating evidence indicates that apolipoprotein C-III is a multifaceted protein which not only regulates triglyceride metabolism, but also participates in the atherosclerotic lesion formation and several other pathological processes involved in atherosclerosis. Based on data from experiments and clinical trials, some novel therapies such as antisense technology emerge.

Human umbilical cord mesenchymal stem cell-derived extracellular vesicles loaded with TFCP2 activate Wnt/ß-catenin signaling to alleviate preeclampsia.

BACKGROUND: Failures in invasive extravillous trophoblasts (EVTs) migration into the maternal uterus have been noticed in preeclampsia (PE). Human umbilical cord mesenchymal stem cell (hUCMSC)-derived extracellular vesicles (EVs) have been highlighted for the role as a potential therapeutic method in PE. This study intends to investigate the mechanistic basis of hUCMSCs-derived EVs loaded with bioinformatically identified TFCP2 in the activities of EVTs of PE. METHODS: Primary human EVTs were exposed to hypoxic/reoxygenation (H/R) to mimic the environment encountered in PE. The in vivo PE-like phenotypes were induced in mice by reduced uterine perfusion pressure (RUPP) surgery. CCK-8, Transwell and flow cytometry assays were performed to detect proliferation, migration, invasion and apoptosis of H/R-exposed EVTs. More importantly, EVs were extracted from hUCMSCs and transduced with ectopically expressed TFCP2, followed by co-culture with EVTs. RESULTS: TFCP2 was found to be down-regulated in the preeclamptic placental tissues and in H/R-exposed EVTs. hUCMSCs-EVs loaded with TFCP2 activated the Wnt/ß-catenin pathway, thereby promoting the proliferative, migratory, and invasive potential of EVTs. Furthermore, overexpression of TFCP2 alleviated PE-like phenotypes in mice, which was associated with activated Wnt/ß-catenin pathway. CONCLUSION: From our data we conclude that hUCMSCs-EVs overexpressing TFCP2 may be instrumental for the therapeutic targeting and clinical management of PE.

Soat1 mediates the mouse strain effects on cholesterol loading-induced endoplasmic reticulum stress and CHOP expression in macrophages.

We previously demonstrated that AKR vs. DBA/2 mouse bone marrow derived macrophages have higher levels of free cholesterol and lower levels of esterified cholesterol after cholesterol loading, and that AKR, but not DBA/2, macrophages induced C/EBP homologous protein (CHOP) expression after cholesterol loading. We earlier determined that the free and esterified cholesterol level effect is due to a truncation in the sterol O-acyltransferase 1 (Soat1) gene, encoding acetyl-coenzyme A acetyltransferase 1 (ACAT1). Here we examined the mechanism for the differential induction of CHOP by cholesterol loading. CHOP was induced in both strains after incubation with tunicamycin, indicating both strains have competent endoplasmic reticulum stress pathways. CHOP was induced when DBA/2 macrophages were cholesterol loaded in the presence of an ACAT inhibitor, indicating that the difference in free cholesterol levels were responsible for this strain effect. This finding was confirmed in macrophages derived from DBA/2 embryonic stem cells. Cholesterol loading of Soat1 gene edited cells, mimicking the AKR allele, led to increased free cholesterol levels and restored CHOP induction. The upstream pathway of free cholesterol induced endoplasmic reticulum stress was investigated; and, RNA-dependent protein kinase-like endoplasmic reticulum kinase (PERK) and inositol-requiring enzyme 1 α protein kinase (IRE1α) pathways were required for maximal CHOP expression.

Goals of non-high density lipoprotein cholesterol need to be adjusted in Chinese acute coronary syndrome patients: Findings from the CCC-ACS project.

BACKGROUND: Guidelines recommended non-high density lipoprotein cholesterol (non-HDL-C) as a co-primary target, and set non-HDL-C goals as 30 mg/dl higher than low-density lipoprotein cholesterol (LDL-C) goals. However, the value is largely uncertain in Chinese patients. METHODS: We assigned non-HDL-C values at the same percentiles correspondent to LDL-C goals for patients from the Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome (CCC-ACS) Project. We calculated the differences between non-HDL-C and LDL-C and proposed appropriate adding values according to LDL-C and TG concentrations. RESULTS: Among 73,495 patients, 17.7% used lipid-lowering agents before admission. Of these, 27.2% achieved LDL-C <70 mg/dl while 39.4% achieved non-HDL-C <100 mg/dl. The mean difference between non-HDL-C and LDL-C was 23.2 mg/dl, which could be affected by LDL-C and TG concentrations. Importantly, of patients with LDL-C concentrations ≤100 mg/dl, the mean differences were 19.1 mg/dl in patients with TG ≤150 mg/dl and 24.6 mg/dl in patients with TG >150 mg/dl. CONCLUSIONS: There are significant differences between LDL-C and non-HDL-C in Chinese ACS patients. For secondary prevention, on average, the adding values should be 20 mg/dl for patients with TG ≤150 mg/dl and 25 mg/dl for patients with TG >150 mg/dl when LDL-C goals of 70 mg/dl is achieved.

ANGPTL8: An Important Regulator in Metabolic Disorders.

Long-term controversy regarding the role of angiopoietin-like protein 8 (ANGPTL8) in beta-cell proliferation and diabetes progression made it a research spotlight. Recently, the controversy was resolved. Although ANGPTL8 could not control beta-cell expansion and islet function, ANGPTL8 was still considered as a novel but atypical member in the ANGPTL family because of its unique structure and crucial effects on lipid metabolism. Besides, ANGPTL8 also participated in some other disorders such as non-alcoholic fatty liver disease and renal dysfunction. Understanding the features of ANGPTL8 may offer new diagnostic and therapeutic approaches to metabolic-related diseases. Therefore, we reviewed most recent findings about ANGPTL8 and aimed to provide an integrated picture of ANGPTL8.

ApoCIII enrichment in HDL impairs HDL-mediated cholesterol efflux capacity.

Apolipoprotein CIII (apoCIII) has been reported to be tightly associated with triglyceride metabolism and the susceptibility to coronary artery disease (CAD). Besides, apoCIII has also been found to affect the anti-apoptotic effects of HDL. However, the effect of apoCIII on HDL-mediated cholesterol efflux, the crucial function of HDL, has not been reported. A hospital-based case-control study was conducted to compare the apoCIII distribution in lipoproteins between CAD patients and nonCAD controls and to explore the relationship between HDL-associated apoCIII (apoCIIIHDL) and HDL-mediated cholesterol efflux. One hundred forty CAD patients and nighty nine nonCAD controls were included. Plasma apoCIII, apoCIIIHDL and cholesterol efflux capacity was measured. The apoCIIIHDL ratio (apoCIIIHDL over plasma apoCIII) was significantly higher in CAD patients than that in control group (0.52 ± 0.24 vs. 0.43 ± 0.22, P = 0.004). Both apoCIIIHDL and apoCIIIHDL ratio were inversely correlated with cholesterol efflux capacity (r = -0.241, P = 0.0002; r = -0.318, P < 0.0001, respectively). Stepwise multiple regression analysis revealed that the apoCIIIHDL ratio was an independent contributor to HDL-mediated cholesterol efflux capacity (standardized ß = -0.325, P < 0.001). This study indicates that the presence of apoCIII in HDL may affect HDL-mediated cholesterol efflux capacity, implying the alternative role of apoCIII in the atherogenesis.