SORBS2 as a molecular target for atherosclerosis in patients with familial hypercholesterolemia.

BACKGROUND: Familial hypercholesterolemia (FH) is a metabolic disease in which patients are prone to develop premature atherosclerosis (AS). Sorbin and SH3 Domain Containing 2 (SORBS2) is known to play a role in coronary heart disease (CHD). However, the mechanism underlying SORBS2 involvement in the development of hypercholesterolemia remains unknown. Here, we investigated the effects of SORBS2 on inflammation and foam cell formation and its underlying mechanisms. METHODS: Using Bioinformatics analysis, we established that SORBS2 is upregulated in patients with FH. Circulating concentrations of SORBS2 were measured using ELISA kit (n = 30). The association between circulating SORBS2 levels and inflammatory factors or lipid indexes were conducted using Spearman correlation analysis. We further conducted in vitro experiments that the expression of SORBS2 were analyzed, and SORBS2 siRNA were transfected into oxidized LDL (OxLDL)-induced macrophages, followed by western blot and immunofluorescence. RESULTS: Circulating SORBS2 levels were positively associated with inflammatory factors and lipid indexes. We also observed that high in vitro expression of SORBS2 in OxLDL-induced macrophages. After SORBS2 silencing, Nod like receptor family pyrin domain-containing 3 protein(NLRP3)-Caspase1 activation and NF-κB activation were attenuated, and secretion of pro-inflammatory cytokines (IL-1ß and IL-18) was decreased. Moreover, SORBS2 silencing blocked reactive oxygen species (ROS) production and lipid accumulation, and promoted cholesterol efflux through ABCG1-PPARγ pathway. CONCLUSIONS: SORBS2 regulates lipid-induced inflammation and foam cell formation, and is a potential therapeutic target for hypercholesterolemia.

Gas permeation through nanoporous single-walled carbon nanotubes: the confinement effect.

The gas permeation through nanoscale membranes like graphene has been extensively studied by experiments and empirical models. In contrast to planar membranes, the single-walled carbon nanotube has a natural confined hollow structure, which shall affect the gas permeation process. We perform molecular dynamics simulations to investigate the effect of the nanotube diameter on the gas permeation process. It is found that the permeance constant increases with the increase of the nanotube diameter, which can not be explained by existing empirical models. We generalize the three-state model to describe the diameter dependence for the permeance constant, which discloses a distinctive confinement-induced adsorption phenomenon for the gas molecule on the nanotube's inner surface. This adsorption phenomenon effectively reduces the pressure of the bulk gas, leading to the decrease of the permeance constant. These results illustrate the importance of the adsorption within the confined space on the gas permeation process.

The effect of layer number on the gas permeation through nanopores within few-layer graphene.

Few-layer graphene has been widely regarded as an efficient filter for gas separation, but the effect of the layer number on the gas permeation process is still unclear. To explore the layer number effect, we perform molecular dynamics simulations to investigate the gas permeation through a nanopore within the few-layer graphene. Our numerical simulations show that the permeation constant decreases with increasing layer number, which is analyzed based on the macroscopic Kennard empirical model. The macroscopic model is in good agreement with the numerical result in the limit of large layer number, but there are obvious deviations for the medium layer number. We generalize the macroscopic model by considering the nanoscale effect from the surface morphology of the nanoscale pore, which can well describe the layer number dependence for the gas permeation constant in the full range. These results provide valuable information for the application of few-layer graphene in the gas permeation field.

Population pharmacokinetics of the anti-PD-1 antibody camrelizumab in patients with multiple tumor types and model-informed dosing strategy.

Camrelizumab, a programmed cell death 1 (PD-1) inhibitor, has been approved for the treatment of patients with relapsed or refractory classical Hodgkin lymphoma, nasopharyngeal cancer and non-small cell lung cancer. The aim of this study was to perform a population pharmacokinetic (PK) analysis of camrelizumab to quantify the impact of patient characteristics and to investigate the appropriateness of a flat dose in the dosing regimen. A total of 3092 camrelizumab concentrations from 133 patients in four clinical trials with advanced melanoma, relapsed or refractory classical Hodgkin lymphoma and other solid tumor types were analyzed using nonlinear mixed effects modeling. The PKs of camrelizumab were properly described using a two-compartment model with parallel linear and nonlinear clearance. Then, covariate model building was conducted using stepwise forward addition and backward elimination. The results showed that baseline albumin had significant effects on linear clearance, while actual body weight affected intercompartmental clearance. However, their impacts were limited, and no dose adjustments were required. The final model was further evaluated by goodness-of-fit plots, bootstrap procedures, and visual predictive checks and showed satisfactory model performance. Moreover, dosing regimens of 200 mg every 2 weeks and 3 mg/kg every 2 weeks provided similar exposure distributions by model-based Monte Carlo simulation. The population analyses demonstrated that patient characteristics have no clinically meaningful impact on the PKs of camrelizumab and present evidence for no advantage of either the flat dose or weight-based dose regimen for most patients with advanced solid tumors.

Platelet-to-lymphocyte ratio relates to poor prognosis in elderly patients with acute myocardial infarction.

BACKGROUND: The platelet to lymphocyte ratio (PLR) is a novel biomarker to predict the prognosis of acute myocardial infarction (AMI) patients. AIM: The study aimed to evaluate the in-hospital outcomes of elderly patients with AMI and assessed the prognostic value of PLR on in-hospital adverse events. METHODS: A total of 1,001 patients were divided into an older group (n = 560) and a younger group (n = 441) based on age ≥ 60 years and successfully underwent primary percutaneous coronary intervention (PCI) within 12 h after presentation. Total white blood cells (WBCs), neutrophils, lymphocytes, and platelets counts were measured at admission. RESULTS: The incidence of heart rupture, acute heart failure, total adverse events, and death resulting from all events were significantly higher in patients ≥ 60 years than in younger patients, whereas the incidence of postoperative angina and reinfarction were similar between groups. Regarding blood counts, total white blood cells, neutrophils, lymphocytes, and platelets were lower in the older group than in the younger group. The platelet-to-lymphocyte ratio (PLR) was significantly higher in the older group. In receiver operating characteristic curve analysis, high PLR > 147 predicted adverse events (specificity 72% and sensitivity 63%). In multiple logistic regression analysis, age, hypertension, and PLR were identified as independent predictors of adverse events. CONCLUSIONS: The in-hospital outcomes of elderly patients with acute myocardial infarction were poor. PLR was an independent risk factor for in-hospital adverse events, which suggested that strong inflammation and prothrombotic status may contribute to the poor prognoses of elderly patients.

Beneficial impact of epigallocatechingallate on LDL-C through PCSK9/LDLR pathway by blocking HNF1α and activating FoxO3a.

BACKGROUND: Green tea drinking has been proven to lower lipid and exert cardiovascular protection, while the potential mechanism has not been fully determined. This study was to investigate whether the beneficial impact of epigallocatechingallate (EGCG), a type of catechin in green tea on lipids is associated with proprotein convertase subtilisin/kexin type 9 (PCSK9) pathways. METHODS: We studied the effects and underlying molecular mechanism of EGCG or green tea on regulating cholesterol from human, animal and in vitro. RESULTS: In the age- and gender-matched case control observation, we found that individuals with frequent tea consumption (n = 224) had the lower plasma PCSK9 and low density lipoprotein cholesterol (LDL-C) levels compared with ones without tea consumption (n = 224, p < 0.05). In the high fat diet (HFD) fed rats, EGCG administration significantly lowered circulating PCSK9 concentration and liver PCSK9 expression, along with up-regulated LDL receptor (LDLR) expression but decreased level of LDL-C. In hepatic cell study, similar results were obtained regarding the impact of EGCG on LDLR and PCSK9 expression. The assay transposase-accessible chromatic with high-throughput sequencing (ATAC-seq) and subsequent results suggested that two transcription factors, hepatocyte nuclear factor-1α (HNF-1α) and forkhead box class O (FoxO) 3a involved in inhibitory action of EGCG on PCSK9 expression. CONCLUSIONS: The present study demonstrates that EGCG suppresses PCSK9 production by promoting nuclear FoxO3a, and reducing nuclear HNF1α, resulting in up-regulated LDLR expression and LDL uptake in hepatocytes. Thereby inhibiting liver and circulating PCSK9 levels, and ultimately lowering LDL-C levels.

Prognostic utility of lipoprotein(a) combined with fibrinogen in patients with stable coronary artery disease: a prospective, large cohort study.

BACKGROUND: Elevated lipoprotein(a) [Lp(a)] and fibrinogen (Fib) are both associated with coronary artery disease (CAD). The atherogenicity of Lp(a) can be partly due to the potentially antifibrinolytic categories. We hypothesize that patients with higher Lp(a) and Fib may have worse outcomes. METHODS: In this prospective study, we consecutively enrolled 8,417 Chinese patients with stable CAD from March 2011 to March 2017. All subjects were divided into 9 groups according to Lp(a) (Lp(a)-Low, Lp(a)-Medium, Lp(a)-High) and Fib levels (Fib-Low, Fib-Medium, Fib-High) and followed up for CVEs, including nonfatal acute myocardial infarction, stroke, and cardiovascular mortality. Kaplan-Meier, Cox regression and C-statistic analyses were performed. RESULTS: During a median of 37.1 months' follow-up, 395 (4.7%) CVEs occurred. The occurrence of CVEs increased by Lp(a) (3.5 vs. 5.3 vs. 5.6%, p = 0.001) and Fib (4.0 vs. 4.4 vs. 6.1%, p < 0.001) categories. When further classified into 9 groups by Lp(a) and Fib levels, the CVEs were highest in the 9th (Lp(a)-High and Fib-High) compared with the 1st (Lp(a)-Low and Fib-Low) group (7.2 vs. 3.3%, p < 0.001). The highest risk of subsequent CVEs was found in the 9th group (HRadjusted 2.656, 95% CI 1.628-4.333, p < 0.001), which was more significant than Lp(a)-High (HRadjusted 1.786, 95% CI 1.315-2.426, p < 0.001) or Fib-High (HRadjusted 1.558, 95% CI 1.162-2.089, p = 0.003) group. Moreover, adding the combined Lp(a) and Fib increased the C-statistic by 0.013. CONCLUSION: Combining Fib and Lp(a) enhance the prognostic value for incident CVEs beyond Lp(a) or Fib alone.

Association of small dense low-density lipoprotein with cardiovascular outcome in patients with coronary artery disease and diabetes: a prospective, observational cohort study.

BACKGROUND: Elevation in small dense low-density lipoprotein (sdLDL) is common in patients with diabetes mellitus (DM), which has already been reported to be associated with incidence of coronary artery disease (CAD). The aim of the present study was to investigate the prognostic value of plasma sdLDL level in patients with stable CAD and DM. METHODS: A total of 4148 consecutive patients with stable CAD were prospectively enrolled into the study and followed up for major cardiovascular events (MACEs) up to 8.5 years. Plasma sdLDL level was measured in each patient by a direct method using automated chemistry analyzer. The patients were subsequently divided into four groups by the quartiles of sdLDL and the association of sdLDL level with MACEs in different status of glucose metabolism [DM, Pre-DM, normal glycaemia regulation (NGR)] was evaluated. RESULTS: A total of 464 MACEs were documented. Both Kaplan-Meier analysis and Cox regression analysis indicated that the patients in quartile 4 but not quartile 2 or 3 of sdLDL level had significantly higher rate of MACEs than that in lowest quartile. When the prognostic value of high sdLDL was assessed in different glucose metabolism status, the results showed that the high sdLDL plus DM was associated with worse outcome after adjustment of confounding risk factors (hazard ratio: 1.83, 95% confident interval: 1.24-2.70, p < 0.05). However, no significant association was observed for high sdLDL plus Pre-DM or NGR. CONCLUSIONS: The present study firstly indicated that elevated levels of plasma sdLDL were associated with increased risk of MACEs among DM patients with proven CAD, suggesting that sdLDL may be useful for CAD risk stratification in DM.

The longitudinal association of remnant cholesterol with cardiovascular outcomes in patients with diabetes and pre-diabetes.

BACKGROUND: The atherogenicity of remnant cholesterol (RC) has been underlined by recent guidelines, which was linked to coronary artery disease (CAD), especially for patients with diabetes mellitus (DM). This study aimed to examine the prognostic value of plasma RC in the patients with CAD under different glucose metabolism status. METHODS: Fasting plasma RC were directly calculated or measured in 4331 patients with CAD. Patients were followed for the occurrence of major adverse cardiovascular events (MACEs) and categorized according to both glucose metabolism status [DM, pre-DM, normoglycemia (NG)] and RC levels. Cox proportional hazards model was used to calculate hazard ratios (HRs) with 95% confidence intervals. RESULTS: During a mean follow-up of 5.1 years, 541 (12.5%) MACEs occurred. The risk for MACEs was significantly higher in patients with elevated RC levels after adjustment for potential confounders. No significant difference in MACEs was observed between pre-DM and NG groups (p > 0.05). When stratified by combined status of glucose metabolism and RC, highest levels of calculated and measured RC were significant and independent predictors of developing MACEs in pre-DM (HR: 1.64 and 1.98; both p < 0.05) and DM (HR: 1.62 and 2.05; both p < 0.05). High RC levels were also positively associated with MACEs in patients with uncontrolled DM. . CONCLUSIONS: In this large-scale and long-term follow-up cohort study, data firstly demonstrated that higher RC levels were significantly associated with the worse prognosis in DM and pre-DM patients with CAD, suggesting that RC may be a target for patients with impaired glucose metabolism.

Prognostic utility of heart-type fatty acid-binding protein in patients with stable coronary artery disease and impaired glucose metabolism: a cohort study.

BACKGROUND: Heart-type fatty acid-binding protein (H-FABP) is a novel marker of myocardial injury and has been reported to be associated with cardiovascular diseases (CVD) including patients with diabetes mellitus (DM). Unfortunately, its prognostic value in patients with CVD and impaired glucose metabolism (IGM) is unclear. The objective of this study was to investigate the prognostic value of H-FABP in CVD patients with IGM. METHODS: A total of 4594 patients with angiography-proven coronary artery disease (CAD) were enrolled and divided into subgroup according to glucose metabolism status (normal glucose regulation [NGR], pre-DM, and DM). Baseline levels of H-FABP were measured using latex immunoturbidimetric method. The cardiovascular events (CVE) were defined as cardiovascular death, myocardial infarction, stroke and coronary revascularization. Cox regression and Kaplan-Meier analysis were used to evaluate the relations of H-FABP and glucose metabolism status to CVEs. RESULTS: During the follow-up period with up to 7.1 years, 380 CVEs occurred. Patients with CVE had higher levels of H-FABP compared to those without CVE (p < 0.001). Interestingly, H-FABP levels were also elevated in DM and pre-DM groups compared with NGR group (p < 0.001), when combined glucose metabolism status with H-FABP stratification, patients in the highest tertile of H-FABP appeared to have higher risk of CVEs with pre-DM (adjusted hazard ratio [HR]: 1.855, 95% confidential intervals [CIs] 1.076-3.214; p = 0.033) and DM (adjusted HR: 2.560, 95% CIs 1.409-4.650; p = 0.002). The Kaplan-Meier curve indicated that DM patients with the highest H-FABP levels were associated with the greatest risk of CVEs (p < 0.05). CONCLUSIONS: Our data firstly showed that elevated H-FABP levels were associated with worse outcomes in CAD patients with pre-DM and DM, which provided the novel information that H-FABP might be a prognostic marker for clinical outcomes among patients with CAD and IGM.

Long-term prognostic utility of low-density lipoprotein (LDL) triglyceride in real-world patients with coronary artery disease and diabetes or prediabetes.

BACKGROUND: Recent guidelines highlighted the association between atherosclerosis and triglyceride-enriched lipoproteins in patients with impaired glucose metabolism. However, evidence from prospective studies for long-term prognostic utility of low-density lipoprotein triglyceride (LDL-TG) in real-world patients with prediabetes (Pre-DM) or diabetes mellitus (DM) and coronary artery disease (CAD) is currently not available. The aim of the present study was to evaluate the impact of LDL-TG on major adverse cardiovascular events (MACEs) in patients with stable CAD under different glucose metabolism status. METHODS: A total of 4381 patients with CAD were consecutively enrolled and plasma LDL-TG level was measured by an automated homogeneous assay. They were categorized according to both status of glucose metabolism [DM, Pre-DM, normal glycaemia regulation (NGR)] and tertiles of LDL-TG. All subjects were followed up for the occurrence of MACEs. RESULTS: During a median of 5.1 (interquartile range 3.9 to 5.9) years' follow-up, 507 (11.6%) MACEs occurred. Cubic spline models showed a significant association between LDL-TG and MACEs in DM and Pre-DM but not in NGR. When the combined effect of elevated LDL-TG and glucose disorders was considered for risk stratification, the medium tertile of LDL-TG plus DM, and the highest tertile of LDL-TG plus Pre-DM or plus DM subgroups were associated with significantly higher risk of MACEs after adjustment of confounders including triglyceride [hazard ratios (95% confidence intervals): 1.843 (1.149-2.955), 1.828 (1.165-2.867), 2.212 (1.396-3.507), all p < 0.05]. Moreover, adding LDL-TG into the original model increased the C-statistic from 0.687 to 0.704 (∆C-statistic = 0.016, p = 0.028) and from 0.734 to 0.749 (∆C-statistic = 0.014, p = 0.002) in Pre-DM and DM, respectively. CONCLUSIONS: In this longitudinal cohort study on real-world practice, higher LDL-TG was associated with worse outcomes among Pre-DM and DM patients with stable CAD.

Liraglutide downregulates hepatic LDL receptor and PCSK9 expression in HepG2 cells and db/db mice through a HNF-1a dependent mechanism.

BACKGROUND: Proprotein convertase subtilisin/kexin type 9 (PCSK9), a major regulator of cholesterol homeostasis, is associated with glucose metabolism. Liraglutide, a glucagon-like peptide-1 receptor agonist, can increase insulin secretion in a glucose-dependent manner and lower blood glucose. We aimed to investigate the relationship between liraglutide and PCSK9. METHODS: At the cellular level, the expressions of PCSK9 and hepatocyte nuclear factor 1 alpha (HNF1α) protein in HepG2 cells stimulated by liraglutide was examined using Western blot. Seven-week old db/db mice and wild type (WT) mice were administered either liraglutide (200 µg/kg) or equivoluminal saline subcutaneously, twice daily for 7 weeks. Fasting glucose level, food intake and body weight were measured every week. After the 7-week treatment, the blood was collected for lipid and PCSK9 levels detection and the liver was removed from the mice for oil red O staining, immunohistochemical analysis, immunofluorescence test and Western bolt. RESULTS: Firstly, liraglutide suppressed both PCSK9 and HNF1α expression in HepG2 cells in a time and concentration dependent manner. Secondly, liraglutide induced weight loss in WT and db/db mice, decreased serum PCSK9, glucose and lipid levels and improved hepatic accumulation in db/db but not WT mice. Thirdly, liraglutide reduced both hepatic PCSK9 and low-density lipoprotein receptor (LDLR) expression with a decrease in HNF1α in db/db mice but not in WT mice. CONCLUSIONS: Liraglutide suppressed PCSK9 expression through HNF1α-dependent mechanism in HepG2 cells and db/db mice, and decreased LDLR possibly via PCSK9-independent pathways in db/db mice.

Familial Hypercholesterolemia Phenotype in Chinese Patients Undergoing Coronary Angiography.

OBJECTIVE: Familial hypercholesterolemia (FH) is characterized by an elevated low-density lipoprotein cholesterol and increased risk of premature coronary artery disease. However, the general picture and mutational spectrum of FH in China are far from recognized, representing a missed opportunity for the investigation. APPROACH AND RESULTS: A total of 8050 patients undergoing coronary angiography were enrolled. The diagnosis of clinical FH was made using Dutch Lipid Clinic Network criteria, and the information of relatives was obtained by inquiring for the probands or from their own medical records of certain clinics/hospitals. Molecular analysis of FH was performed using target exome sequencing in LDLR (low-density lipoprotein cholesterol receptor gene), APOB (apolipoprotein B gene), and PCSK9 (proprotein convertase subtilisin/kexin type 9 gene). As a result, 3.5% of the patients with definite/probable FH phenotype (definite 1.0% and probable 2.5%) were identified. Women FH had fewer premature coronary artery disease (women <60, or men <55 years of age) when compared with men FH (70.6% versus 82.7%; P<0.001), whereas angiographic extension of coronary artery disease was significantly increased with FH diagnosis in both men and women (P<0.001). Patterns of medication use in definite/probable FH were as follows: nontreated, 20.6%; low intensity, 6.0%; moderate intensity, 68.3%; and high intensity, 5.0%. However, none of them had achieved the low-density lipoprotein cholesterol <100 mg/dL. Additionally, mutational analysis was performed in 245 definite/probable FH cases, and risk variants were identified in 115 patients, giving a detection rate of 46.9%. CONCLUSIONS: We showed firsthand a common identification but poor treatment of patients with FH phenotype in Chinese coronary angiography patients. Genetic data in our FH cases might contribute to update the frequency and spectrum of Chinese FH scenarios.

Genetic basis of index patients with familial hypercholesterolemia in Chinese population: mutation spectrum and genotype-phenotype correlation.

BACKGROUND: Although there have been many reports in the genetics of familial hypercholesterolemia (FH) worldwide, studies in regard of Chinese population are lacking. In this multi-center study, we aim to characterize the genetic spectrum of FH in Chinese population, and examine the genotype-phenotype correlations in detail. METHODS: A total of 285 unrelated index cases from China with clinical FH were consecutively recruited. Next-generation sequencing and bioinformatics tools were used for mutation detection of LDLR, APOB and PCSK9 genes and genetic analysis. RESULTS: Overall, the detection rate is 51.9% (148/285) in the unrelated index cases with a total of 119 risk variants identified including 84 in the LDLR gene, 31 in APOB and 4 in PCSK9 gene. Twenty-eight variants were found in more than one individual and LDLR c.1448G > A (p. W483X) was most frequent one detected in 9 patients. Besides, we found 8 (7 LDLR and 1 APOB) novel variants referred as "pathogenic (or likely pathogenic) variants" according to in silico analysis. In the phenotype analysis, patients with LDLR null mutation had significantly higher LDL cholesterol level than LDLR defective and APOB/PCSK9 mutation carriers and those with no mutations (p < 0.001). Furthermore, 13 double heterozygotes, 16 compound heterozygotes and 5 true LDLR homozygotes were identified and the true LDLR homozygotes had the most severe phenotypes. CONCLUSIONS: The present study confirmed the heterogeneity of FH genetics in the largest Chinese cohort, which could replenish the knowledge of mutation spectrum and contribute to early screening and disease management.

Enhanced pro-protein convertase subtilisin/kexin type 9 expression by C-reactive protein through p38MAPK-HNF1α pathway in HepG2 cells.

Plasma C-reactive protein (CRP) concentration is associated positively with cardiovascular risk, including dyslipidemia. We suggested a regulating role of CRP on pro-protein convertase subtilisin/kexin type 9 (PCSK9), a key regulator of low-density lipoprotein (LDL) metabolism, and demonstrated the PCSK9 as a pathway linking CRP and LDL regulation. Firstly, experiments were carried out in the presence of human CRP on the protein and mRNA expression of PCSK9 and LDL receptor (LDLR) in human hepatoma cell line HepG2 cells. Treatment with CRP (10 µg/ml) enhanced significantly the mRNA and protein expression of PCSK9 and suppressed the expression of LDLR. Of note, a late return of LDLR mRNA levels occurred at 12 hrs, while the LDLR protein continued to decrease at 24 hrs, suggesting that the late decrease in LDLR protein levels was unlikely to be accounted for the decrease in LDL mRNA. Secondly, the role of PCSK9 in CRP-induced LDLR decrease and the underlying pathways were investigated. As a result, the inhibition of PCSK9 expression by small interfering RNA (siRNA) returned partly the level of LDLR protein and LDL uptake during CRP treatment; CRP-induced PCSK9 increase was inhibited by the p38MAPK inhibitor, SB203580, resulting in a significant rescue of LDLR protein expression and LDL uptake; the pathway was involved in hepatocyte nuclear factor 1α (HNF1α) but not sterol responsive element-binding proteins (SREBPs) preceded by the phosphorylation of p38MAPK. These findings indicated that CRP increased PCSK9 expression by activating p38MAPK-HNF1α pathway, with a certain downstream impairment in LDL metabolism in HepG2 cells.

Leptin decreases the expression of low-density lipoprotein receptor via PCSK9 pathway: linking dyslipidemia with obesity.

BACKGROUND: Previous studies have suggested that people with obesity showed elevated serum levels of leptin as well as lipid dysfunction and proprotein convertase subtilisin/kexin type 9 (PCSK9) played an important role in the regulation of lipid metabolism recently. The aim of this study was to determine if leptin participated in regulating the uptake of low-density lipoproteins (LDL) in hepatocytes via PCSK9. METHODS: HepG2 cells were treated with human recombinant leptin. The impact of leptin on cellular low density lipoprotein receptor (LDLR) and PCSK9 protein levels was determined by Western blot. Dil-LDL uptake assay was performed to examine the LDLR function. Specific small interfering RNAs (siRNAs) were used to interfere the expressions of target proteins. RESULTS: The expression of LDLR and LDL uptake could be significantly down-regulated by leptin treatment while the expressions of PCSK9 and hepatocyte nuclear factor 1α (HNF1α) were enhanced in HepG2 cells. Furthermore, inhibition of PCSK9 or HNF1α expression by siRNAs rescued the reduction of LDLR expression and LDL uptake by leptin. We found that leptin activated the p38 mitogen-activated protein kinase (p38MAPK) signaling pathway. Moreover, the changes of the expressions of HNF1α, PCSK9, LDLR, and LDL uptake induced by leptin could be blocked by p38MAPK inhibitor (SB203580). Additionally, leptin attenuated the up-regulation of LDLR caused by atorvastatin in HepG2 cells. CONCLUSIONS: These findings indicated firstly that leptin reduced LDLR levels in hepatocyte via PCSK9 pathway, suggesting that PCSK9 might be a alternative target for dyslipidemia in the obesity.

Positive correlation of plasma PCSK9 levels with HbA1c in patients with type 2 diabetes.

BACKGROUND: Proprotein convertase subtilisin/kexin type 9 (PCSK9) has been demonstrated to be involved in not only lipid metabolism but also glucose homeostasis. Glycated haemoglobin (HbA1c ) is a 'gold standard' for monitoring long-term glycaemic control. However, the correlation of plasma PCSK9 levels with HbA1c remains undetermined. METHODS: We consecutively enrolled 805 subjects undergoing coronary angiography, including 176 patients with type 2 diabetes mellitus (T2DM) and 629 non-diabetic patients. The baseline characteristics were collected, and serum PCSK9 level was assessed by ELISA. Univariable regression analysis and multiple-variable regression analysis were used to examine the associations of PCSK9 with HbA1c . Furthermore, the HbA1c was compared across the tertiles of PCSK9 levels. And also, PCSK9 levels were compared in poorly controlled (HbA1c ≥ 7.0%) and well-controlled (HbA1c < 7.0%) patients with T2DM. RESULTS: PCSK9 levels were positively correlated with low-density lipoprotein cholesterol in both T2DM and non-T2DM. Univariable regression analysis revealed a positive association between PCSK9 and HbA1c in patients with T2DM (ß = 0.255, p = 0.001) but not in patients without diabetes (ß = 0.061, p = 0.128). Multiple-variable regression analysis exhibited that PCSK9 was independently correlated with HbA1c in T2DM after adjustment for traditional atherosclerotic risk factors (ß = 0.197, p = 0.020). Moreover, HbA1c level was higher in patients with the highest tertile of PCSK9 than that in the lowest tertile (p = 0.042). Additionally, higher levels of PCSK9 were found in poorly controlled group compared with the well-controlled group (p = 0.029). CONCLUSIONS: Data suggest a positive correlation of PCSK9 levels with HbA1c in patients with T2DM but not in patients without T2DM, indicating a potential role of PCSK9 in T2DM. Copyright © 2015 John Wiley & Sons, Ltd.

Circulating MicroRNAs as Novel Diagnostic Biomarkers for Very Early-onset (≤40 years) Coronary Artery Disease.

OBJECTIVE: Very early-onset coronary artery disease (CAD) is a great challenge in cardiovascular medicine throughout the world, especially regarding its early diagnosis. This study explored whether circulating microRNAs (miRNAs) could be used as potential biomarkers for patients with very early-onset CAD. METHODS: We performed an initial screening of miRNA expression using RNA isolated from 20 patients with angiographically documented very early-onset CAD and 20 age- and sex-matched normal controls. For further confirmation, we prospectively examined the miRNAs selected from 40 patients with very early-onset CAD and 40 angiography-normal controls. RESULTS: A total of 22 overexpressed miRNAs and 22 underexpressed miRNAs were detected in the initial screening. RT-qPCR analysis of the miRNAs obtained from the initial screening revealed that four miRNAs including miR-196-5p, miR-3163-3p, miR-145-3p, and miR-190a-5p exhibited significantly decreased expression in patients compared with that in controls (P<0.05). The areas under the receiver operating characteristic curve for these miRNAs were 0.824 (95% CI, 0.731-0.917; P<0.001), 0.758 (95% CI, 0.651-0.864; P<0.001), 0.753 (95% CI, 0.643-0.863; P<0.001), and 0.782 (95% CI, 0.680-0.884; P<0.001), respectively, in the validation set. CONCLUSION: To our knowledge, this is an advanced study to report about four serum miRNAs (miR-196-5p, miR-3163-3p, miR-145-3p, and miR-190a-5p) that could be used as novel biomarkers for the diagnosis of very early-onset CAD.

Cyclohexadepsipeptides of the isaridin class from the marine-derived fungus Beauveria felina EN-135.

Three new cyclohexadepsipeptides of the isaridin class including isaridin G (1), desmethylisaridin G (2), and desmethylisaridin C1 (3), along with three related known metabolites (4-6), were isolated and identified from the marine bryozoan-derived fungus Beauveria felina EN-135. The structures of these compounds were elucidated on the basis of extensive spectroscopic analysis, and the structures and absolute configurations of compounds 1-3 were confirmed by single-crystal X-ray diffraction analysis. The crystal structures showed the presence of ß-turns for the Tyr(3)/N-Me-Val(4) and Phe(3)/N-Me-Val(4) amide bonds in compounds 2 and 3, respectively, in the cis conformations, which were opposite other reported isaridins. The conformations of the HMPA(1)-Pro(2) amide bond in compound 2 are different in the solution and in the crystal structures, which showed trans and cis geometries, respectively, while compounds 1 and 3 do not exhibit this phenomenon. Each of the isolated compounds was evaluated for antimicrobial activity and brine shrimp lethality. Compound 3 exhibited antibacterial activity against E. coli with an MIC value of 8 µg/mL.

[Expression and prognostic significance of galectin-1 and galectin-3 in benign nevi and melanomas].

OBJECTIVE: To study the expression and prognostic significance of galectin-1 and galectin-3 in different melanocytic lesions. METHODS: The expression of galectin-1 and galectin-3 in 39 cases of benign nevus, 58 cases of primary cutaneous melanoma, 24 cases of primary mucosal melanoma, 69 cases of melanoma with lymph node metastasis and 8 cases of melanoma with distant metastasis were studied by immunohistochemistry and tissue microarray. RESULTS: The expression of galectin-1 and galectin-3 was higher in benign nevi than in melanomas (P < 0.01). The nuclear expression of galectin-3 was higher in primary cutaneous melanomas than in primary mucosal melanomas or melanomas with metastases (P < 0.01, respectively). The expression correlated with age of patients (P < 0.05), necrosis (P < 0.05) and survival time (P < 0.01). Clark's level also correlated with survival time in patients with cutaneous melanomas (P = 0.037). TNM staging was the only independent prognostic factor for melanomas (P < 0.01). CONCLUSIONS: The expression of galectin-1 and galectin-3 is decreased in melanomas. The decrease in nuclear expression of galectin-3 may represent a poor prognostic factor for melanomas. TNM staging is an independent prognostic factor which influences the survival time.