The modification of serum lipids after acute coronary syndrome and importance in clinical practice

Discordance analysis for apolipoprotein and lipid measures for predicting myocardial infarction in statin-treated patients with coronary artery disease: a cohort study

BACKGROUND

The optimal apolipoprotein or lipid measures for identifying statin-treated patients with coronary artery disease (CAD) at residual cardiovascular risk remain controversial. This study aimed to compare the predictive powers of apolipoprotein B (apoB), non-high-density lipoprotein cholesterol (non-HDL-C), low-density lipoprotein cholesterol (LDL-C), apoB/apolipoprotein A-1 (apoA-1) and non-HDL-C/HDL-C for myocardial infarction (MI) in CAD patients treated with statins in the setting of secondary prevention.

METHODS

The study included 9191 statin-treated CAD patients with a five-year median follow-up. All measures were analyzed as continuous variables and concordance/discordance groups by medians. The hazard ratio (HR) with 95% CI was estimated by Cox proportional hazards regression. Patients were classified by the clinical presentation of CAD for further analysis.

RESULTS

The high-apoB-low-LDL-C and the high-non-HDL-C-low-LDL-C categories yielded HR of 1.40 (95% CI: 1.04-1.88) and 1.51 (95% CI: 1.07-2.13) for MI, respectively, whereas discordant high LDL-C with low apoB or non-HDL-C was not associated with the risk of MI. No association of MI with discordant apoB versus non-HDL-C, apoB/apoA-1 versus apoB, non-HDL-C/HDL-C versus non-HDL-C, or apoB/apoA-1 versus non-HDL-C/HDL-C was observed. Similar patterns were found in patients with acute coronary syndrome. In contrast, no association was observed between any concordance/discordance category and the risk of MI in patients with chronic coronary syndrome.

CONCLUSIONS

ApoB and non-HDL-C better predict MI in statin-treated CAD patients than LDL-C, especially in patients with acute coronary syndrome. ApoB/apoA-1 and non-HDL-C/HDL-C show no superiority to apoB and non-HDL-C for predicting MI.

Short-Course High-Intensity Statin Treatment during Admission for Myocardial Infarction and LDL-Cholesterol Reduction-Impact on Tailored Lipid-Lowering Therapy at Discharge

We hypothesized that a short-course high-intensity statin treatment during admission for myocardial infarction (MI) could rapidly reduce LDL-C and thus impact the choice of lipid-lowering therapy (LLT) at discharge. Our cohort comprised 133 MI patients (62.71 ± 11.3 years, 82% male) treated with atorvastatin 80 mg o.d. during admission. Basal LDL-C levels before admission were analyzed. We compared lipid profile variables before and during admission, and LLT at discharge was registered. Achieved theoretical LDL-C levels were estimated using LDL-C during admission and basal LDL-C as references and compared to LDL-C on first blood sample 4-6 weeks after discharge. A significant reduction in cholesterol from basal levels was noted during admission, including total cholesterol, triglycerides, HDL-C, non-HDL-C, and LDL-C (-39.23 ± 34.89 mg/dL, p < 0.001). LDL-C levels were reduced by 30% in days 1-2 and 40-45% in subsequent days (R2 0.766, p < 0.001). Using LDL-C during admission as a reference, most patients (88.7%) would theoretically achieve an LDL-C < 55 mg/dL with discharge LLT. However, if basal LDL-C levels were considered as a reference, only a small proportion of patients (30.1%) would achieve this lipid target, aligned with the proportion of patients with LDL-C < 55 mg/dL 4-6 weeks after discharge (36.8%). We conclude that statin treatment during admission for MI can induce a significant reduction in LDL-C and LLT at discharge is usually prescribed using LDL-C during admission as the reference, which leads to insufficient LDL-C reduction after discharge. Basal LDL-C before admission should be considered as the reference value for tailored LLT prescription.

Genetic variants, gene expression, and soluble CD36 analysis in acute coronary syndrome: Differential protein concentration between ST-segment elevation myocardial infarction and unstable angina

Background

Atherosclerosis plays an important role in the pathophysiology of acute coronary syndrome (ACS). CD36 is a scavenger receptor involved in lipid metabolism. Some single‐nucleotide variants in the non‐coding region could indirectly alter the expression and the function of the protein.

Objective

The aim of this study was to investigate the gene and protein expression associated with CD36 variants (rs1194182;C > G; rs1049654;C > A, rs1334512;G > T, and rs3211892;G > A) in ACS patients from the western Mexican population.

Methods

We recruited 310 ACS patients and 308 subjects in the control group (CG). Genotyping was determined by TaqMan SNP genotyping assays. CD36 expression at the mRNA level was quantified by TaqMan gene expression assays. Soluble CD36 (sCD36) was measured by enzyme‐linked immunosorbent assay.

Results

We show that rs1194182G > C variant provides a protective effect with a 1.7‐fold lower susceptibility to develop ACS (p  = 0.03); however, this association was masked by diabetes and dyslipidemia. We observed a higher sCD36 concentration in patient with ST‐segment elevation myocardial infarction (STEMI) compared with patients with unstable angina (UA) (p  = 0.038). Likewise, in diabetic patients versus non‐diabetic (p < 0.001). We observed in patients an increase in CD36 mRNA expression (1.91 times higher) than in the CG (p  = 0.02).

Conclusion

The rs1194182 seems to be associated with diabetes in a risky manner, in ACS patients and protective for dyslipidemia in both groups. The concentration of sCD36 seems to be associated with the clinical spectrum of the ACS patients and the presence of diabetes, since patients with STEMI present significantly elevated level compared with UA.

Prognostic value of triglyceride/glucose index in patients with ST-segment elevation myocardial infarction

Aim: New parameters are emerging to predict prognosis in patients with ST-segment elevation myocardial infarction (STEMI). In this study we aimed to determine and compare the prognostic values of some metabolic indices in terms of predicting long-term mortality in patients with STEMI. Method: A total of 1900 nondiabetic patients who presented with STEMI and underwent percutaneous coronary intervention were included in the study. Multivariable Cox proportional regression analysis was used to determine and compare the predictive performance of triglyceride-glucose (TyG) index, triglyceride-high density lipoprotein ratio (Ty/HDL) and admission glucose. Results: In multivariable Cox regression analysis, the model based on TyG index had better predictive performance than the Ty/HDL and admission blood glucose. Conclusion: The TyG index is more informative than Ty/HDL and admission glucose level to predict long-term all-cause mortality.

PCSK9 Promotes Cardiovascular Diseases: Recent Evidence about Its Association with Platelet Activation-Induced Myocardial Infarction

Cardiovascular diseases are the leading cause of death worldwide, with the majority of the cases being heart failure due to myocardial infarction. Research on cardiovascular diseases is currently underway, particularly on atherosclerosis prevention, to reduce the risk of myocardial infarction. Proprotein convertase subtilisin/kexin type 9 (PCSK9) has been reported to play a role in lipid metabolism, by enhancing low-density lipoprotein (LDL) receptor degradation. Therefore, PCSK9 inhibitors have been developed and found to successfully decrease LDL plasma levels. Recent experimental studies have also implicated PCSK9 in platelet activation, having a key role during atherosclerosis progression. Although numerous studies have addressed the role of PCSK9 role in controlling hypercholesterolemia, studies and discussions exploring its involvement in platelet activation are still limited. Hence, here, we address our current understanding of the pathophysiological process involved in atherosclerosis-induced myocardial infarction (MI) through platelet activation and highlight the molecular mechanisms used by PCSK9 in regulating platelet activation. Undoubtedly, a deeper understanding of the relationship between platelet activation and the underlying molecular mechanisms of PCSK9 in the context of MI progression will provide a new strategy for developing drugs that selectively inhibit the most relevant pathways in cardiovascular disease progression.

Lower LDL-cholesterol levels associated with increased inflammatory burden in patients with acute ST-segment elevation myocardial infarction

OBJECTIVE

Association of low-density lipoprotein cholesterol and highly sensitive C-reactive protein in ST-elevation myocardial infarction patients was assessed in this study.

METHODS

591 consecutive patients who were hospitalized with a diagnosis of ST-elevation myocardial infarction were enrolled and assigned into tertiles according to their serum low-density lipoprotein cholesterol levels. Differences in highly sensitive C-reactive protein among low-density lipoprotein cholesterol tertiles and correlations between highly sensitive C-reactive protein and low-density lipoprotein cholesterol were assessed.

RESULTS

Highly sensitive C-reactive protein levels differed significantly among the groups (p<0.001) and found to be highest in the low-density lipoprotein cholesterol tertile 1 and lowest in the low-density lipoprotein cholesterol tertile 3 (post-hoc p-values: tertile 1 vs. 2 <0.001; tertile 1 vs. 3 <0.001; tertile 2 vs. 3=0.019). There was a negative correlation between hs-CRP and both low-density lipoprotein cholesterol (r=-0.332, p<0.001) and total cholesterol (r=-0.326, p<0.001). There was also a negative correlation between highly sensitive C-reactive protein and high-density lipoprotein cholesterol, though the strength of this relationship was weak (r=-0.103, p=0.014).

CONCLUSION

Lower low-density lipoprotein cholesterol levels are associated with higher inflammatory burden in patients with acute STEMI. Further studies are required to elucidate the significance of low-density lipoprotein cholesterol levels in ST-elevation myocardial infarction settings.

Association of dyslipidemia with the severity and mortality of coronavirus disease 2019 (COVID-19): a meta-analysis

Background

The numbers of confirmed cases of coronavirus disease 2019 (COVID-19) and COVID-19 related deaths are still increasing, so it is very important to determine the risk factors of COVID-19. Dyslipidemia is a common complication in patients with COVID-19, but the association of dyslipidemia with the severity and mortality of COVID-19 is still unclear. The aim of this study is to analyze the potential association of dyslipidemia with the severity and mortality of COVID-19.

Methods

We searched the PubMed, Embase, MEDLINE, and Cochrane Library databases for all relevant studies up to August 24, 2020. All the articles published were retrieved without language restriction. All analysis was performed using Stata 13.1 software and Mantel–Haenszel formula with fixed effects models was used to compare the differences between studies. The Newcastle Ottawa scale was used to assess the quality of the included studies.

Results

Twenty-eight studies involving 12,995 COVID-19 patients were included in the meta-analysis, which was consisted of 26 cohort studies and 2 case–control studies. Dyslipidemia was associated with the severity of COVID-19 (odds ratio [OR] = 1.27, 95% confidence interval [CI] 1.11–1.44, P = 0.038, I² = 39.8%). Further, patients with dyslipidemia had a 2.13-fold increased risk of death compared to patients without dyslipidemia (95% CI 1.84–2.47, P = 0.001, I² = 66.4%).

Conclusions

The results proved that dyslipidemia is associated with increased severity and mortality of COVID-19. Therefore, we should monitor blood lipids and administer active treatments in COVID-19 patients with dyslipidemia to reduce the severity and mortality.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12985-021-01604-1.

Two RECK Splice Variants (Long and Short) Are Differentially Expressed in Patients with Stable and Unstable Coronary Artery Disease: A Pilot Study

Primary prevention is crucial for coronary heart disease (CAD) and the identification of new reliable biomarkers might help risk stratification or predict adverse coronary events. Alternative splicing (AS) is a less investigated genetic factors implicated in CAD etiology. We performed an RNA-seq study on PBMCs from CAD patients and control subjects (CTR) and observed 113 differentially regulated AS events (24 up and 89 downregulated) in 86 genes. The RECK (Reversion-inducing-cysteine-rich protein with Kazal motifs) gene was further analyzed in a larger case study (24 CTR subjects, 72 CAD and 32 AMI patients) for its Splicing-Index FC (FC = −2.64; p = 0.0217), the AS event involving an exon (exon 18), and its role in vascular inflammation and remodeling. We observed a significant downregulation of Long RECK splice variant (containing exon 18) in PBMCs of AMI compared to CTR subjects (FC = −3.3; p < 0.005). Interestingly, the Short RECK splice variant (lacking exon 18) was under-expressed in AMI compared to both CTR (FC = −4.5; p < 0.0001) and CAD patients (FC = −4.2; p < 0.0001). A ROC curve, constructed combining Long and Short RECK expression data, shows an AUC = 0.81 (p < 0.001) to distinguish AMI from stable CAD patients. A significant negative correlation between Long RECK and triglycerides in CTR group and a positive correlation in the AMI group was found. The combined evaluation of Long and Short RECK expression levels is a potential genomic biomarker for the discrimination of AMI from CAD patients. Our results underline the relevance of deeper studies on the expression of these two splice variants to elucidate their functional role in CAD development and progression.

Alterations in the lipid profile associate with a dysregulated inflammatory, prothrombotic, anti-fibrinolytic state and development of severe acute kidney injury in coronavirus disease 2019 (COVID-19): A study from Cincinnati, USA

BACKGROUND AND AIMS

Reduction of atherogenic lipoproteins is often the ultimate goal of nutritional interventions, however this is complicated given that hypolipidemia is frequently observed in coronavirus disease 2019 (COVID-19) patients. We aimed to explore the association of hypolipidemia with patient outcomes in terms of immunothrombosis and multiorgan injury, focusing on specialized apolipoproteins apo A1 and apo B.

METHODS

Lipid profiles of 50 COVID-19 patients and 30 sick controls presenting to the Emergency Department (ED) were measured in this prospective observational study. The primary outcome was development of severe acute kidney injury (AKI). Need for hospitalization and ICU admission were secondary outcomes. Lipoproteins were analyzed for independent association with serum creatinine (SCr) increase ratio and correlated with a wide panel of biomarkers.

RESULTS

COVID-19 cohort had significantly lower apo A1 (p = 0.006), and higher apo B/apo A1 ratio (p = 0.041). Patients developing severe AKI had significantly lower LDL-C (p = 0.021). Apo B/apo A1 was associated with 2.25-fold decrease in serum SCr increase ratio, while LDL-C with a 1.5% decrease. Hypolipidemia correlated with low plasminogen, ADAMTS13 activity/VWF:Ag, and high inflammatory biomarkers (CRP, IL-6, IL-8, IL-10), plasminogen activator inhibitor-1 (PAI-1), ED creatinine, and SCr increase ratio.

CONCLUSION

Although favored in dietetics, findings of a low LDL-C in COVID-19 patients should be alarming in light of our observations. Low apo B/apo A1 ratio and LDL-C are predictive of renal deterioration in COVID-19 patients, and low LDL-C in particular may potentially serve to indicate COVID-19 related AKI driven by disrupted fibrinolysis and a secondary thrombotic microangiopathy-like process.

Plasma kinetics of mature PCSK9, furin-cleaved PCSK9, and Lp(a) with or without administration of PCSK9 inhibitors in acute myocardial infarction

BACKGROUND

There are two types of circulating proprotein convertase subtilisin/kexin type 9 (PCSK9), mature and furin-cleaved. Most types of lipoprotein(a) [Lp(a)], an independent risk factor of cardiovascular events, bind to mature PCSK9.

OBJECTIVE

This study examined the effects of monoclonal anti-PCSK9 antibody on plasma PCSK9 and Lp(a) levels in acute myocardial infarction (MI).

METHODS

Acute MI patients (n=36) were randomly divided into evolocumab (140mg; n=17) and non-evolocumab (n=19) groups. Changes in plasma PCSK9 and Lp(a) levels were monitored before and 1, 3, 5, 10, and 20 days after evolocumab administration.

RESULTS

In the non-evolocumab group, plasma levels of mature PCSK9, furin-cleaved PCSK9, and Lp(a) (236.4±57.3ng/mL, 22.4±5.8ng/mL, and 19.2.±16.5mg/dL, respectively) significantly increased by day 3 (408.8±77.1ng/mL, p<0.001; 47.2±15.7ng/mL, p<0.001; and 39.7±21.3mg/dL, p<0.005, respectively) and returned to the baseline by day 10 or 20. In the evolocumab group, mature PCSK9 significantly increased by >1000ng/mL with a simultaneous decline of furin-cleaved PCSK9 below the measurement sensitivity level after day 3. The incremental area under the curve for plasma Lp(a) levels was significantly smaller in the evolocumab group compared with the non-evolocumab group (p=0.038).

CONCLUSION

Mature and furin-cleaved PCSK9 are transiently upregulated after MI onset. Evolocumab significantly increases mature PCSK9 and decreases furin-cleaved PCSK9 and might inhibit transient increase of plasma Lp(a) in acute MI.

Is Lipoprotein (a) a Risk Factor for Coronary Artery Ectasia?

Background

The pathophysiology of coronary artery ectasia (CAE) is under investigated and not well understood. Atherosclerosis is considered as the main etiologic factor for CAE in adults where more than 50% of CAE patients have atherosclerosis. Recently, lipoprotein (a) (Lp(a)) has emerged as a powerful risk factor for atherosclerosis and coronary artery disease (CAD). Serum levels of Lp(a) in patients with CAE have not been investigated. We assumed that Lp(a) may play a role in the pathogenesis of CAE. Principally, our study aims to identify whether Lp(a) is an independent risk factor for CAE.

Methods

Our study is a prospective pilot study. Study population was collected prospectively from pool of patients referred for elective cardiac catheterization at Jordan University Hospital (JUH) in the period extending from February 17, 2018 to June 31, 2018. Patients were referred for elective coronary angiography after being interviewed and physically examined by a cardiologist (HA). Patients with known history of CAD or who are already on anti-lipidemic drugs either documented in the medical records or by interviewing patients for history of revascularization were excluded from the study.

Results

Regarding the primary outcome, there was no significant difference in Lp(a) concentrations between normal and ectasia groups in the general sample (median: 17.5mg/dL vs. 20.4 mg/dL, P value = 0.38).

Conclusions

Our study concludes that there is no detected relationship between elevated Lp(a) levels and developing CAE. CAE was more common in patients with low high-density lipoprotein (HDL) level (compared with patients with normal coronaries), higher total cholesterol level (compared with patients with non-obstructive stenosis) and higher hemoglobin A1c (HbA1c).

Lipid Profile of Patients with Acute Myocardial Infarction (AMI)

Introduction  Irrespective of underlying hyperlipidemia, the serum lipid profile witnesses a phasic fluctuation immediately after a major cardiovascular event. This study aims to evaluate the change in serum lipid profile in patients with acute myocardial infarction (AMI). Methods It was a prospective, cross-sectional study conducted in the department of cardiology, Shalamar Hospital, and Punjab Institute of Cardiology, from October until December 2018, focusing on patients admitted with ST-elevation myocardial infarction (STEMI). The patient's demographics and lipid profile (in mg/dl) within the first 24 hours and after 48 hours of the event were recorded. Results The mean serum total cholesterol (TC) levels decreased from 207.5 ± 30.5 to 192.4 ± 49.3 after 48 hours (p-value <0.0001). Mean serum triglyceride (TGs) levels increased from 153.8 ± 10.2 to 183.8 ± 14.8 (p-value <0.0001). Mean serum low density lipid-cholesterol (LDL-C) decreased from 149.0 ± 41.2 to 133.4 ± 54.0 (p-value = 0.0003). Mean serum high density lipid-cholesterol (HDL-C) decreased from 46.6 ± 9.9 to 40.7 ± 11.8 (p-value <0.0001). Conclusion Phasic fluctuations in serum lipid profile are observed after acute myocardial infarction (AMI). The trend that follows include reduced TC, LDL-C, and HDL-C, and increased TGs. Periodic lipid profile must be evaluated in all patients admitted for AMI to understand the changing trend, initiate lifestyle measures to reach target lipid levels, and predict the choice of lipid-lowering therapy.

Low expression of PRMT5 in peripheral blood may serve as a potential independent risk factor in assessments of the risk of stable CAD and AMI

Background

Protein arginine methyltransferases (PRMTs) can catalyse the methylation of arginine and participate in many important cellular reaction processes. The purpose of this research is to determine whether the expression levels of the PRMT5 gene in peripheral blood can be used as a biomarker for predicting the risk of Acute Myocardial Infarction (AMI).

Methods

In this research, peripheral blood was collected from 91 patients with AMI and 87 patients with stable coronary artery disease (CAD). Real-time fluorescent quantitative PCR was performed to measure the expression levels of the PRMT5 gene at the mRNA level, and a western blot analysis was performed to measure the expression levels of the PRMT5 gene at the protein level.

Results

The results indicate that at both the RNA and protein levels, the expression levels of the PRMT5 gene in peripheral blood from patients with AMI are significantly lower than those in peripheral blood from patients with stable CAD (Z = − 4.813, P = 0.000). The low expression of the PRMT5 gene is relevant to the Gensini score of the coronary artery (rs = − 0.205, P = 0.015) but is irrelevant to the serum level of blood lipids, level of cardiac troponin (rs = − 0.125, P = 0.413) and time intervals of occurrence (rs = − 0.146, P = 0.211). Patients who have a low PRMT5 expression in the peripheral blood are 5.472 times more likely to suffer from AMI than other patients.

Conclusion

Compared to stable CAD patients, AMI patients have a lower expression of the PRMT5 gene in their peripheral blood. Patients who have low PRMT5 gene expression in the peripheral blood are more likely to suffer from AMI than those with stable CAD. A low expression of the PRMT5 gene serves as an independent risk factor for the occurrence of AMI.

Lipid paradox in patients with acute myocardial infarction: Potential impact of malnutrition

BACKGROUND & AIMS

Aggressive lipid reduction is recommended for patients with AMI, but reverse epidemiology, the lipid paradox, has been reported in several clinical studies. The cause of lipid paradox remains uncertain, and nutrition is one possible explanation. In this single-center retrospective study, we investigated the relationships between baseline LDL concentrations and clinical outcomes in patients with AMI, stratified by different nutritional status.

METHODS

Totally 409 patients were enrolled for analysis. The Nutritional Risk Index (NRI) was used to estimate the risk of malnutrition. Subjects were grouped into tertiles according to their NRIs. Clinical outcomes were compared among patients with varying NRIs and LDL levels.

RESULTS

Patients in the lowest NRI tertile had increased incidences of in-hospital mortality, cardiogenic shock, decompensated heart failure, renal failure, and sepsis. This tertile was also associated with increased long-term mortality during the follow-up period of 832 ± 744 days. Mortality was increased among patients with baseline LDL concentrations ≤70 mg/dL in the lowest NRI tertile (log rank test, p = 0.0257), but not in the high or median tertiles. Moreover, baseline LDL level ≤70 mg/dL was an independent risk factor of all-cause mortality (adjusted hazard ratio = 1.73; 95% confidence interval, 1.01-2.94; p = 0.045) in the lowest NRI tertile.

CONCLUSIONS

Lipid paradox was observed in the high-risk of malnutrition population among patients with AMI. Aggressive lipid-lowering therapy is still recommended for patients with AMI and fair nutritional status. However, when treating patients at high risk of malnutrition, the improvement of nutritional status may be more beneficial than strict LDL control.

The Therapeutic Efficacy of Danhong Injection Combined With Percutaneous Coronary Intervention in Acute Coronary Syndrome: A Systematic Review and Meta-Analysis

Background: Percutaneous coronary intervention (PCI) is widely used in treatment of acute coronary syndrome (ACS) clinically. It is believed that Danhong injection (DHI) extracted from salviae miltiorrhizae and flos carthami combined with PCI could increase the therapeutic efficacy on ACS. We provide an updated meta-analysis with detailed information on combination of DHI and PCI therapy.

Materials and Methods: Electronic databases were searched for appropriate articles without language limitations on key words before October 22, 2017. All trails were screened according to certain criteria. Quality of eligible studies was also assessed. We made a detailed record of outcome measurements. RevMan 5.3 software was used to perform the meta-analysis.

Results: 14 articles involving 1533 patients with ACS were selected. Compared to PCI treatment alone, total efficacy rate (TER) was enhanced and major adverse cardiovascular events (MACE) were reduced significantly for the combination of DHI and PCI (P < 0.00001). Vascular endothelial function was improved by significantly decreasing the contents of ET-1, vWF and increasing the levels of NO and FMD (P < 0.00001). The serum levels of IL-1, IL-6, IL-18, TNF-α, LpPLA2, MMP-9, and pentraxin-3 were significantly decreased (P < 0.00001), whereas IL-10 in serum was increased (P < 0.00001), indicating a stronger anti-inflammatory effect of the combination. The combination therapy decreased the serum levels of CD62P, PAGT, PADT, FIB-C significantly (P < 0.05), which was beneficial for preventing coagulation of platelets. Blood lipid was also affected by regulating TC, TG, LDL, and HDL, but the results were not statistically significant (P > 0.05). Cardiac function was improved by increasing LEVF (P = 0.006) but not LVED (P = 0.08). The combination treatment was associated with an improvement in antioxidant effect by decreasing MDA and increasing SOD significantly (P < 0.00001).

Conclusion: Combination of DHI and PCI in treatment of ACS could improve TER and reduce incidence of MACE after PCI therapy. These effects may be mediated by combined actions of several mechanisms. However, these results of this study should be handled cautiously due to the limitations of this research. Several rigorous RCTs are in need to confirm these findings.

The relationship of serum endocan levels and anti-TNF-alpha therapy in patients with ankylosing spondylitis

OBJECTIVE

Endocan is a marker for vascular pathogenesis and important mediator of angiogenesis that strongly associates with inflammation and vascular diseases. Growing evidence suggest that inflammatory cytokine tumor necrosis factor (TNF-alpha) plays a role in its regulation and secretion, whereas TNF-alpha inhibitors may have the opposite influence. The aim of this research is to investigate the association between serum endocan and anti-TNF-alpha drug treatment in patients with ankylosing spondylitis (AS).

METHODS

Serum endocan levels were analyzed in 42 patients with AS under anti-TNF-alpha usage. Control group consisted of 37 patients with AS who are not receiving anti-TNF drugs. Endocan is analyzed using ESM-1 ELISA kits. The blood glucose and lipid measurements of patients were also assessed.

RESULTS

There was no significant change in serum endocan levels among groups. The total cholesterol, triglyceride, and LDL-C levels were higher in patients receiving anti-TNF-alpha; however, differences were not significant. There was no significant correlation between serum endocan levels and blood lipid measurements.

CONCLUSION

Anti-TNF-alpha treatment does not affect serum endocan levels in patients with AS. This research has been first to evaluate the relationship between serum endocan and anti-TNF-alpha therapy in AS. Future studies are necessary to verify the exact role of anti-TNF-alpha therapy on serum endocan levels in patients with AS.

Lipid Biomarkers for Risk Assessment in Acute Coronary Syndromes

PURPOSE OF REVIEW

The objective of this review was to summarize evidence gathered for the prognostic value of routine and novel blood lipids and lipoproteins measured in patients with acute coronary syndromes (ACS).

RECENT FINDINGS

Data supports clear association with risk and actionable value for non-high-density lipoprotein (Non-HDL) cholesterol and plasma ceramides in a setting of ACS. The prognostic value and clinical actionability of apolipoprotein B (apoB) and lipoprotein(a) [Lp(a)] in ACS have not been thoroughly tested, while the data for omega-3 fatty acids and oxidized low-density lipoprotein (Ox-LDL) are either untested or more varied. Measuring basic lipids, which should include Non-HDL cholesterol, at the time of presentation for ACS is guideline mandated. Plasma ceramides also provide useful information to guide both treatment decisions and follow-up. Additional studies targeting ACS patients are necessary for apoB, Lp(a), omega-3 fatty acids, and Ox-LDL.

Oxidized low density lipoprotein facilitates tumor necrosis factor‑α mediated chondrocyte death via autophagy pathway

We aimed to investigate the role of oxidized low density lipoprotein (ox-LDL) in tumor necrosis factor-α (TNF-α) mediated chondrocyte death and explore the mechanisms. Ten osteoarthritis (OA) and normal control cartilage tissue and synovial fluid (SF) samples were collected, and the expression of lectin-like ox-LDL receptor-1 (LOX-1) and ox-LDL level was examined by real time quantitative PCR and enzyme-linked immunosorbent assay (ELISA). An in vitro chondrocyte model was established by the introduction of TNF-α and ox-LDL, cell death was analyzed by trypan blue assay and the mechanisms were explored based on the apoptosis related pathway and autophagy pathway. Significantly increased ox-LDL level (70.30±17.83 vs. 37.22±19.97, P<0.05) in SF sample and LOX-1 expression level (0.51±0.10 vs. 0.32±0.04, P<0.05) in cartilage tissue was found in OA patients compared to those corresponding samples from control subjects. Ox-LDL could facilitate TNF-α mediated chondrocyte death and this effect could be blocked by LOX-1 antibody neutralization. Autophagy inhibition by 3-MA and Atg-5 siRNA could reverse the cell death effect mediated by TNF-α and ox-LDL co-treatment on chondrocytes. Oxidized low density lipoprotein facilitates tumor necrosis factor-α mediated chondrocyte death via its interaction with LOX-1, and autophagy is involved in the mechanisms.

Extended Serum Lipid Profile Predicting Long-Term Survival in Patients Treated for Abdominal Aortic Aneurysms

BACKGROUND

Individuals treated for abdominal aortic aneurysms (AAAs) are high-risk patients in whom better risk prediction could improve survival. Contemporary serum lipid parameters, such as apolipoproteins and lipoprotein subfractions, may improve or complement the prognostic value of traditional serum lipids. The aim of this study was to ascertain the extended serum lipid profiles, long-term prognosis and their association in AAA patients.

METHODS

Altogether 498 patients treated for AAAs and with available serum lipid values were retrospectively analysed. Contemporary lipid parameters were estimated using a neural network model, the extended Friedewald formula.

RESULTS

Younger age, smoking and urgent or emergency surgery were associated with an unfavourable, and coronary disease and previous stroke with a favourable lipid profile. In multivariable analysis-in addition to advanced age, aneurysm rupture, smoking, pulmonary disease and diabetes-high triglycerides and traditional LDL cholesterol were significant independent risk factors for mortality, HR 1.84 (95% CI 1.20-2.81) and 1.79 (95% CI 1.18-2.73), respectively, while higher EFW-IDL cholesterol was associated with better survival, HR 0.31 (95% CI 0.19-0.65). Including serum lipid parameters improved the prediction of 5-year survival (NRI = 17.7%, p = 0.016).

CONCLUSIONS

Extended serum lipid parameters complement risk prediction of patients treated for AAAs. An unfavourable lipid profile is associated with treatment of AAA earlier in life and with inferior long-term survival.

CREBH mediates metabolic inflammation to hepatic VLDL overproduction and hyperlipoproteinemia

Metabolic inflammation is closely associated with hyperlipidemia and cardiovascular disease. However, the underlying mechanisms are not fully understood. The current study established that cAMP-responsive-element-binding protein H (CREBH), an acute-phase transcription factor, enhances very-low-density lipoprotein (VLDL) assembly and secretion by upregulating apolipoprotein B (apoB) expression and contributes to metabolic inflammation-associated hyperlipoproteinemia induced by TNFα, lipopolysaccharides (LPS), and high-fat diet (HFD) in mice. Specifically, overexpression of CREBH significantly induced mRNA and protein expression of apoB in McA-7777 cells. Luciferase assay further revealed that the presence of CREBH could significantly increase the activity of the apoB gene promoter. In contrast, genetic depletion of CREBH in mice resulted in significant reduction in expression of hepatic apoB mRNA. Challenging mice with an acute fat load led to upregulation of triglyceride (TG)-rich lipoprotein secretion in wild type mice, but not in CREBH-null mice. TNFα treatment activated hepatic CREBH expression, which in turn enhanced hepatic apoB biosynthesis and VLDL secretion. Metabolic inflammation induced by LPS or HFD also resulted in overproduction of apoB and hyperlipoproteinemia in wild type mice, but not in CREBH-null mice. This study demonstrates that CREBH could be a mediator between metabolic inflammation and hepatic VLDL overproduction in chronic metabolic disorders. This novel finding establishes CREBH as the first transcription factor that regulates apoB expression on the transcriptional level and the subsequent VLDL biosynthesis in response to metabolic inflammation. The study also provides novel insight into the pathogenesis of hyperlipidemia in metabolic syndrome.

KEY MESSAGES

CREBH mediates inflammatory signaling to VLDL overproduction in metabolic stress. Activation of CREBH in inflammation enhances mRNA and protein expression of apoB. CREBH presents a potential novel therapeutic target for hyperlipoproteinemia.

Lipid parameters in patients with acute coronary syndromes versus stable coronary artery disease

BACKGROUND

Differences in lipid parameters between patients with acute coronary syndromes (ACS) and patients with stable coronary artery disease (CAD) are unclear and are addressed in this study.

METHODS

We enrolled 582 patients with angiographically proven stable CAD (of whom 26·9% had diabetes mellitus type 2 (T2DM)) and 182 patients with ACS (of whom 35·8% had T2DM).

RESULTS

HDL cholesterol and apolipoprotein A1 levels were significantly lower in patients with ACS than in patients with CAD (46 ± 16 mg/dL vs. 50 ± 16 mg/dL, P < 0·001, and 139 ± 30 mg/dL vs. 155 ± 31 mg/dL, P < 0·001, respectively). Analysis of covariance (ancova) adjusting for age, gender, smoking, BMI, statin therapy, alcohol use, hypertension and diabetic state confirmed an independent impact of ACS on HDL cholesterol and apolipoprotein A1 levels (F = 24·1; P < 0·001). In contrast, total cholesterol, LDL cholesterol, non-HDL cholesterol and apolipoprotein B levels did not differ significantly between patients with ACS and patients with stable CAD.

CONCLUSION

HDL cholesterol and apolipoprotein A1 levels are lower in patients with ACS than in patients with stable CAD.

Serial measurement of lipid profile and inflammatory markers in patients with acute myocardial infarction

Serum concentration of lipids and lipoproteins changes during the course of acute coronary syndrome as a consequence of the inflammatory response. The objective of this study was to evaluate the effect of acute myocardial infarction (AMI) on the levels of lipid profile and inflammatory markers. We investigated 400 patients with AMI who were admitted within 24 h of onset of symptoms. Serum levels of total cholesterol (TC), triglyceride (TG), low density lipoprotein (LDL) and high density lipoprotein (HDL) were determined by standard enzymatic methods along with high sensitive C-reactive protein (hs-CRP) (latex enhanced immunoturbidimetric assay) and cytokines, interleukin (IL)-6 and IL-10 (quantitative ''sandwich'' enzyme-linked immunosorbent assay). The results indicate a trend of reduced TC, LDL, and HDL, and elevated TG levels, along with pro- and anti-inflammatory markers (p < 0.001), between day 1 and the day 2 serum samples of AMI patients. However, corrections in the serum levels have been observed at day 7. Our results demonstrate significant variations in the mean lipid levels and inflammatory markers between days 1, 2 and 7 after AMI. Therefore, it is recommended that the serum lipids should be assessed within 24 hours after infarction. Early treatment of hyperlipidemia provides potential benefits. Exact knowledge regarding baseline serum lipids and lipoprotein levels as well as their varying characteristics can provide a rational basis for clinical decisions about lipid lowering therapy.

Reduced cholesterol is associated with the depressive-like behavior in rats through modulation of the brain 5-HT1A receptor

Background

Low serum cholesterol levels are related to an increased risk of depression and its serious consequences. However, the effect of central cholesterol on depressive disorder and its potential regulatory mechanism is poorly understood. Therefore, brain cholesterol in patients with depression may not only decrease the risk for developing this disease but also increase the beneficial effects of treatment for depression.

Methods

In current study, rats were exposed to chronic mild stress (CMS) for consecutive 28 days, and the depressive-like behavior was tested by sucrose preference test, immobility in the forced swim test, locomotor activity in the open field test, decreased bodyweight and food intake. Additionally, the total cholesterol levels in the medial prefrontal cortex (mPFC) and the hippocampus of rats were measured by gas chromatograph mass spectrometer. Finally, 5-HT1A receptor antagonist WAY100635 was used to determine the potential role of serotonin system in the interaction between central cholesterol and depression.

Results

CMS significantly reduced total cholesterol levels in the mPFC but not in the hippocampus and resulted in depressive-like behavior. Chronic supplementation of cholesterol by food reversed the depressive-like behavior induced by CMS. Furthermore, pre-injection of 5-HT1A receptor antagonist WAY100635 into the mPFC blocked the treatment effects of cholesterol on the reversal of behavioral response.

Conclusion

This finding suggested that cholesterol in the mPFC may have an impact on the sensitivity of the 5-HT1A receptor in the development and treatment of depression. The treatment benefits of cholesterol could be through modulation of the brain 5-HT1A receptor.

Prevalence and characteristics of patients with low levels of low-density lipoprotein cholesterol in northern Denmark: a descriptive study

BACKGROUND

With the emergence of new lipid-lowering therapies, more patients are expected to achieve substantial lowering of low-density lipoprotein cholesterol (LDL-C). However, there are limited data examining the clinical experience of patients with low (<1.3 mmol/L) or very low (<0.65 mmol/L) levels of LDL-C. To provide information on patients with low LDL-C, we identified and characterized persons with low LDL-C using data from Danish medical databases.

METHODS

Using a population-based clinical laboratory database, we identified adults with at least one LDL-C measurement in northern Denmark between 1998 and 2011 (population approximately 1.5 million persons). Based on the lowest measurement during the study period, we divided patients into groups with low (<1.3 mmol/L), moderate (1.3-3.3 mmol/L), or high (>3.3 mmol/L) LDL-C. We described their demographic characteristics, entire comorbidity history, and 90-day prescription history prior to the lowest LDL-C value measured. Finally, we further restricted the analysis to individuals with very low LDL-C (<0.65 mmol/L).

RESULTS

Among 765,503 persons with an LDL-C measurement, 23% had high LDL-C, 73% had moderate LDL-C, and 4.8% had low LDL-C. In the latter group, 9.6% (0.46% of total) had very low LDL-C. Compared with the moderate and high LDL-C categories, the low LDL-C group included more males and older persons with a higher prevalence of cardiovascular disease, diabetes, chronic pulmonary disease, ulcer disease, and obesity, as measured by hospital diagnoses or relevant prescription drugs for these diseases. Cancer and use of psychotropic drugs were also more prevalent. These patterns of distribution became even more pronounced when restricting to individuals with very low LDL-C.

CONCLUSION

Using Danish medical databases, we identified a cohort of patients with low LDL-C and found that cohort members differed from patients with higher LDL-C levels. These differences may be explained by various factors, including prescribing patterns of lipid-lowering therapies.

Proprotein convertase subtilisin/kexin type 9 expression is transiently up-regulated in the acute period of myocardial infarction in rat

BACKGROUND

The proprotein convertase subtilisin/kexin type 9 (PCSK9) has been confirmed as a major factor regulating cholesterol homeostasis and has low-density lipoprotein receptor (LDLR) independent effects. In addition, the pathogenesis of acute myocardial infarction (AMI) involves lipids alteration and other acute phase responses. It remains unknown whether the PCSK9 expression is influenced by the impact of AMI. The present study aimed to investigate the changes of PCSK9 concentration using AMI rat model.

METHODS

AMI (n = 6-8 at each time point) or sham operated (n = 6) adult male rats model were used. Whole blood and liver tissue were collected at 1, 3, 6, 9, 12, 24, 48, and 96 hour (h) post infarction. The plasma PCSK9 concentration was measured by ELISA and lipid profiles were measured by enzymatic assay. The liver mRNA levels of PCSK9, LDLR, sterol response element binding protein-2 (SREBP-2) and hepatocyte nuclear factor 1α (HNF1α) were measured by quantitative real-time PCR.

RESULTS

The plasma PCSK9 concentration was increased from 12 h to 96 h (P < 0.05 vs. control). Paralleled with the enhanced plasma PCSK9 concentration, the hepatic PCSK9 mRNA expression was up-regulated by 2.2-fold at 12 h and 4.1-fold at 24 h. Hepatic mRNA levels of LDLR, SREBP-2 and HNF1α were all increased and lipid profiles underwent great changes at this acute period.

CONCLUSIONS

We firstly demonstrated that PCSK9 was transiently up-regulated in the acute period of AMI, which is also driven by transcriptional factors, SREBP-2 and HNF1α, suggesting that the role of PCSK9 in myocardial injury may be needed further study.

Particle-induced pulmonary acute phase response may be the causal link between particle inhalation and cardiovascular disease

Inhalation of ambient and workplace particulate air pollution is associated with increased risk of cardiovascular disease. One proposed mechanism for this association is that pulmonary inflammation induces a hepatic acute phase response, which increases risk of cardiovascular disease. Induction of the acute phase response is intimately linked to risk of cardiovascular disease as shown in both epidemiological and animal studies. Indeed, blood levels of acute phase proteins, such as C-reactive protein and serum amyloid A, are independent predictors of risk of cardiovascular disease in prospective epidemiological studies. In this review, we present and review emerging evidence that inhalation of particles (e.g., air diesel exhaust particles and nanoparticles) induces a pulmonary acute phase response, and propose that this induction constitutes the causal link between particle inhalation and risk of cardiovascular disease. Increased levels of acute phase mRNA and proteins in lung tissues, bronchoalveolar lavage fluid and plasma clearly indicate pulmonary acute phase response following pulmonary deposition of different kinds of particles including diesel exhaust particles, nanoparticles, and carbon nanotubes. The pulmonary acute phase response is dose-dependent and long lasting. Conversely, the hepatic acute phase response is reduced relative to lung or entirely absent. We also provide evidence that pulmonary inflammation, as measured by neutrophil influx, is a predictor of the acute phase response and that the total surface area of deposited particles correlates with the pulmonary acute phase response. We discuss the implications of these findings in relation to occupational exposure to nanoparticles.

How to cite this article: WIREs Nanomed Nanobiotechnol 2014, 6:517–531. doi: 10.1002/wnan.1279

Particle-induced pulmonary acute phase response correlates with neutrophil influx linking inhaled particles and cardiovascular risk

BACKGROUND

Particulate air pollution is associated with cardiovascular disease. Acute phase response is causally linked to cardiovascular disease. Here, we propose that particle-induced pulmonary acute phase response provides an underlying mechanism for particle-induced cardiovascular risk.

METHODS

We analysed the mRNA expression of Serum Amyloid A (Saa3) in lung tissue from female C57BL/6J mice exposed to different particles including nanomaterials (carbon black and titanium dioxide nanoparticles, multi- and single walled carbon nanotubes), diesel exhaust particles and airborne dust collected at a biofuel plant. Mice were exposed to single or multiple doses of particles by inhalation or intratracheal instillation and pulmonary mRNA expression of Saa3 was determined at different time points of up to 4 weeks after exposure. Also hepatic mRNA expression of Saa3, SAA3 protein levels in broncheoalveolar lavage fluid and in plasma and high density lipoprotein levels in plasma were determined in mice exposed to multiwalled carbon nanotubes.

RESULTS

Pulmonary exposure to particles strongly increased Saa3 mRNA levels in lung tissue and elevated SAA3 protein levels in broncheoalveolar lavage fluid and plasma, whereas hepatic Saa3 levels were much less affected. Pulmonary Saa3 expression correlated with the number of neutrophils in BAL across different dosing regimens, doses and time points.

CONCLUSIONS

Pulmonary acute phase response may constitute a direct link between particle inhalation and risk of cardiovascular disease. We propose that the particle-induced pulmonary acute phase response may predict risk for cardiovascular disease.