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There is evidence that the development of atherosclerosis (AS) involves the dysregulation of circular RNAs. This study aimed to investigate the role of circular ubiquitin-specific peptidase 9 X-linked (circUSP9X) in AS cell models. Human umbilical vein endothelial cells (HUVECs) treated with oxidized low-density lipoprotein (ox-LDL) were used as cell models of AS. The expression of circUSP9X, miR-148b-3p, and Kruppel-like factor 5 (KLF5) messenger RNA was measured using quantitative polymerase chain reaction. Cell viability was assessed by Cell Counting Kit-8 assay. Lactate dehydrogenase leakage, malonaldehyde content, and superoxide dismutase activity were investigated using matched commercial kits. Cell apoptosis was detected using flow cytometry assay. The protein levels of apoptosis-related markers and KLF5 were detected by western blot. The release of proinflammatory factors was monitored by enzyme-linked immunosorbent assay. The predicted relationship between miR-148b-3p and circUSP9X or KLF5 was confirmed by dual-luciferase reporter assay or RNA immunoprecipitation assay. CircUSP9X was highly expressed in ox-LDL-treated HUVECs. CircUSP9X knockdown inhibited ox-LDL-induced lactate dehydrogenase leakage, apoptosis, inflammation, and oxidative stress in HUVECs. CircUSP9X directly bound to miR-148b-3p, and KLF5 was a target of miR-148b-3p. CircUSP9X could regulate KLF5 expression by competitively targeting miR-148b-3p. Rescue experiments indicated that circUSP9X knockdown inhibited ox-LDL-induced HUVEC injuries by enriching miR-148b-3p, and miR-148b-3p restoration alleviated ox-LDL-induced HUVEC injuries by degrading KLF5. In conclusion, circUSP9X knockdown relieved ox-LDL-triggered HUVEC injuries during AS progression partly by mediating the miR-148b-3p/KLF5 network.

Introduction: Vascular endothelial injury could induce many cardiovascular diseases. Recently, some studies have indicated that matrix metalloproteinase-7 (MMP-7) was associated with the occurrence and development of cardiovascular diseases. However, whether higher levels of MMP-7 were associated with the occurrence of the vascular endothelial injury is unclear. Material and methods: In this study, ox-LDL was used for the simulation of vascular endothelial injury in HUVECs. Next, we detected the expression of MMP-7 in these cells. After that, we established the cell models with MMP-7 overexpression and knockdown, respectively. At last, the apoptosis and inflammation of HUVECs were detected with corresponding assays. Results: After the stimulation of ox-LDL, the expression of MMP-7 was enhanced compared to the control groups. After the stimulation of ox-LDL and the overexpression of MMP-7, the apoptosis rates of HUVECs were enhanced, while MMP-7 knockdown led to the decreased apoptosis rates of these cells. Furthermore, after the stimulation of ox-LDL and overexpression of MMP-7, the expression of inflammatory factors (IL-6, IL-1β and TNF-α) was promoted. Additionally, the expression of these proteins was repressed after knockdown of MMP-7. Conclusion: MMP-7 aggravated the ox-LDL-induced damage of HUVECs by promoting the apoptosis and inflammation of these cells.

Atherosclerosis is the major cause of cardiovascular disease, and endothelial cell injury is the primary atherogenic factor. Long non-coding RNAs (lncRNAs) are increasingly implicated as critical regulators of disease progression. Still, the role of lncRNA in endothelial cell injury is largely unknown. This issue was explored in control, ox-LDL stimulated, ox-LDL stimulated+transfected negative control vector, and ox-LDL stimulated+SNHG5 overexpression vector EA. hy926 cells. Quantitative real-time PCR used to assess the expression of SNHG5 and miR-26a-5p. Flow cytometry was used to evaluate cell apoptosis. Activity or concentration of SOD, MDA, CAT, and reactive oxygen species (ROS) was measured to assess oxidative stress. Western blotting was used to examine protein-level expression of cleaved Caspase-3, cleaved Caspase-9, and cyt-c in cytoplasm and mitochondria. Potential binding sites between SNHG5 and miR-26a-5p were predicted using Starbase software, and dual-luciferase reporter assays were used to identify target relationships. SNHG5 expression in cells following ox-LDL treatment was downregulated in EA. hy926 cells. Ox-LDL treatment promotes apoptosis, and increased C-Caspase-3, C-Caspase-9, and cytoplasmic cyt-c protein levels. MDA concentration and ROS activity were increased, while the activity of SOD and CAT was decreased. Transfection with SNHG5 reversed the effects of ox-LDL on cell apoptosis and oxidative stress. SNHG5 targeted miR-26a-5p and regulated its expression. miR-26a-5p mimics reversed SNHG5 modulation of apoptosis and oxidative stress. lncRNA SNHG5 targets to miR-26a-5p to regulate vascular endothelial cell injury induced by ox-LDL.

The occurrence of vascular endothelial injury is key to the progression of atherosclerosis (AS). This research explores the expression of lncRNA DLGAP1-AS1 in a mouse model of atherosclerosis and its effect on ox-LDL-induced vascular endothelial cell injury. A mouse model of AS was constructed, and DLGAP1-AS1 expression was detected using the nano real-time PCR method. Vascular endothelial cells (VEC) are categorized into four groups. Flow cytometry detects cell apoptosis, and Western blot detects Bax and Bcl-2 expressions; WST-8 method detects level of SOD. Thiobarbituric acid method, Ammonium molybdate colorimetric method, DCFH-DA method were used to detect MDA, CAT, and reactive oxygen species (ROS) levels, respectively. Bioinformatics software predicted the target genes of DLGAP1-AS1. DLGAP1-AS1 expression was raised in AS mice, apoptotic rate and Bax expression in the ox-LDL group were raised, Bcl-2 expression was abated, MDA and ROS levels were raised, SOD and CAT levels were abated than in control. The si-DLGAP1-AS1+ox-LDL group decreased cell death and Bax expression, increased Bcl-2 expression, decreased MDA and ROS levels, and increased SOD and CAT levels than in the si-NC+ox-LDL group. Down-regulation of DLGAP1-AS1 was targeted in order to promote miR-26a-5p expression. Compared with co-transfection with DLGAP1-AS1 siRNA and inhibitor control, the apoptosis rate and Bax expression were increased after co-transfection with DLGAP1-AS1 siRNA and miR-26a-5p inhibitor, Bcl-2 expression was decreased, and MDA and ROS levels were increased, the level of SOD and CAT were decreased. DLGAP1-AS1 was up-regulated in AS mice and downregulated to promote miR-26a-5p to inhibit ox-LDL-induced vascular endothelial cell death and oxidative damage.

Accumulation of cholesterol‐laden macrophage foam cells characteristic of early stage atherosclerotic lesions. Phenethyl isothiocyanate (PEITC) is a naturally occurring isothiocyanate found in cruciferous vegetables that has reported a variety of activities including antioxidant and anti‐inflammatory properties. However, the protective effect of PEITC on foam cell formation and its precise mechanism is not yet clear. Therefore, we investigated whether PEITC suppresses foam cell formation and regulates the expression of genes related to lipid accumulation, cholesterol efflux, and inflammation in THP‐1 derived‐macrophages. We exposed THP‐1 derived‐macrophages to oxidized low‐density lipoprotein (ox‐LDL) (20 μg/mL) and lipopolysaccharide (LPS) (500 ng/ml) to mimic foam cell formation. Here, PEITC downregulated the expression of lectin‐like oxidized low‐density lipoprotein receptor‐1 (LOX‐1), cluster of differentiation 36 (CD36), scavenger receptor A1 (SR‐A1), and nuclear factor‐κB (NF‐κB), while upregulated ATP binding cassette subfamily A member 1 (ABCA1)/liver‐X‐receptor α (LXR‐α)/peroxisome proliferator‐activated receptor gamma (PPARγ) and sirtuin 1 (SIRT1) expression compared to co‐treated with ox‐LDL and LPS. Taken together, PEITC, at least in part, inhibits foam cell formation and reduces lipid accumulation in foam cells. Therefore, we suggest that PEITC may be a potential candidate for the treatment and prevention of vascular inflammation and atherosclerosis., PEITC control foam cell formation by promoting cholesterol efflux, reducing lipid accumulation, and modulating the SIRT1‐NF‐κB signaling pathway.

Oxidized low density lipoprotein (Ox-LDL) plays an important role in the pathogenesis of atherosclerosis. Recently, we identified two fluorescence-labeled heptapeptides, (FITC)KP6 and (FITC)dKP6, t...

To explore the influence and mechanism of lncRNA SNHG14 on oxidized low-density lipoprotein (oxLDL)-induced vascular endothelial cell injury, cellular levels of SNHG14 and miRNA-93-5p were detected in oxLDL-induced vascular endothelial cells by RT-qPCR, and the levels of MDA, SOD and GSH-Px were detected by ELISA. Flow cytometry was used to detect cellular apoptosis, and western blot analysis was used to determine the abundance of Bcl-2 and Bax proteins. SNHG14 small interfering RNA or miRNA-93-5p mimics were transfected into vascular endothelial cells to interfere with SNHG14 expression or overexpress miRNA-93-5p. To study the effects of interfering with SNHG14 expression or overexpression of miRNA-93-5p, the levels of MDA, SOD and GSH-Px, apoptosis and the levels of Bcl-2 and Bax protein were studied in oxLDL-induced endothelial cells with either altered SNHG14 expression or overexpressed miRNA-93-5p. A dual-luciferase reporter gene experiment verified the regulatory connection between SNHG14 and miRNA-93-5p. After oxLDL acted on vascular endothelial cells, the expression levels of SNHG14 were significantly increased, while the expression levels of miRNA-93-5p were significantly reduced, MDA levels were increased, and SOD and GSH-Px activities were reduced. Both the apoptosis rate and Bax protein levels were significantly increased, and Bcl-2 expression was reduced. Interference with SNHG14 expression or overexpression of miRNA-93-5p can reduce the MDA content in oxLDL-induced vascular endothelial cells, increase the activity of SOD and GSH-Px, and reduce the apoptosis rate and Bax protein levels, and promote Bcl-2 expression. SNHG14 targeted to negatively regulate miRNA-93-5p expression, inhibited miRNA-93-5p expression and reversed the interference of SNHG14 expression with oxLDL-induced variation in MDA, SOD and GSH-Px levels, apoptosis rate, and Bax and Bcl-2 protein levels. Interference of SNHG14 expression may reduce oxidative stress and apoptosis of vascular endothelial cells induced by oxLDL by negatively regulating the expression of miRNA-93-5p.

NO is a free radical gas, identified as Endothelial Derived Releasing Factor (EDRF) and synthesized from L-arginine which plays a dynamic role in defence against onset and development of coronary heart disease. Decreased availability of nitric oxide is one of the important cause for the pathogenesis of atherosclerosis. An accumulation of Low Density Lipoprotein cholesterol (LDL) in the intimal wall is the early step in atherosclerosis. Reduced NO level in the endothelium makes it vulnerable and increase the passage of leukocyte and undergo LDL oxidation in the sub endothelial space which ultimately lead to coronary heart disease. The aim of the study is to assess role of Nitric Oxide and oxidized LDL in CHD subjects. This cross-sectional study was conducted in SRM Medical college Hospital and Research centre on subjects attending the Department of Cardiology and Medicine OP. The study was conducted on 194 subjects in age group

Apoptosis of endothelial cells plays an important role in atherosclerosis (AS). MicroRNAs (miRNAs) have been confirmed to participate in the process of endothelial cell apoptosis. The main purpose of this study was to investigate the mechanism of miR-151 and interleukin-17A (IL-17A) in apoptosis of atherosclerotic endothelial cells. The expression levels of miR-151 in human aortic endothelial cells (HAEC) after Ox-LDL treatment were detected by qRT-PCR. The expression levels of IL-17A were detected by qRT-PCR and Western blot. The effects of miR-151 and IL-17A on the apoptosis rate were detected by flow cytometry. The relationship between miR-151 and IL-17A was assessed by bioinformatics analysis and luciferase assay. The expression levels of miR-151 in HAEC after Ox-LDL treatment were reduced, and the expression of IL-17A was upregulated. MiR-151 and si-IL-17A inhibited the apoptosis rate of aortic endothelial cells treated by Ox-LDL. MiR-151 and si-IL-17A reduced the expression levels of c-caspase-9, c-caspase-3, and BAX proteins in Ox-LDL-treated HAEC and increased the expression levels of Bcl-2. MiR-151 inhibited the apoptosis of endothelial cells in AS, and IL-17A was a new target for miR-151. Our findings provided a potential treatment for atherosclerosis in the treatment of AS.

Oxidized LDL (oxLDL) is a known risk factor for atherogenesis. This study aimed to reveal structural features of oxLDL present in human circulation related to atherosclerosis. When LDL was fractionated on an anion-exchange column, in vivo-oxLDL, detected by the anti-oxidized PC (oxPC) mAb, was recovered in flow-through and electronegative LDL [LDL(-)] fractions. The amount of the electronegative in vivo-oxLDL, namely oxLDL in the LDL(-) fraction, present in patients with acute MI was 3-fold higher than that observed in healthy subjects. Surprisingly, the LDL(-) fraction contained apoA1 in addition to apoB, and HDL-sized particles were observed with transmission electron microscopy. In LDL(-) fractions, acrolein adducts were identified at all lysine residues in apoA1, with only a small number of acrolein-modified residues identified in apoB. The amount of oxPC adducts of apoB was higher in the LDL(-) than in the L1 fraction, as determined using Western blotting. The electronegative in vivo-oxLDL was immunologically purified from the LDL(-) fraction with an anti-oxPC mAb. The majority of PC species were not oxidized, whereas oxPC and lysoPC did not accumulate. Here, we propose that there are two types of in vivo-oxLDL in human circulating plasma and the electronegative in vivo-oxLDL accompanies oxidized HDL.

Low-density lipoprotein (LDL) and oxidized low-density lipoprotein (oxLDL) levels are thought to be related to recurrent stroke. However, the joint association of circulating LDL and oxLDL levels with the outcomes of acute minor ischemic stroke and transient ischemic attack (TIA) remains unclear. The goal of the study was to evaluate whether LDL and oxLDL have a combined effect on outcomes of acute minor stroke and TIA.In the Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events (CHANCE) trial, a subgroup of 3019 patients with baseline oxLDL and LDL levels were analyzed. Patients were divided into four groups according to different combinations of LDL (LDL 3.37 mmol/L, LDL ≥ 3.37 mmol/L) and oxLDL levels (oxLDL13.96 μg/dL, oxLDL ≥ 13.96 μg/dL). The primary outcome was any stroke within 90 days. The secondary outcomes included any stroke within 1 year and ischemic stroke and combined vascular events within 90 days and 1 year. The poor functional outcome included modified Rankin Scale (mRS) 3-6 at 90-day and 12-month follow-up. The association of LDL and oxLDL with the prognosis of patients was examined using multivariable Cox regression models.Among 3019 patients included in this study, the medians (interquartile range) of oxLDL and LDL were 13.96 (6.65-28.81) μg/dL and 3.1 (2.5-3.8) mmol/L, respectively. The cumulative occurrence of recurrent stroke, ischemic stroke, and combined vascular events was 9.74%, 9.54%, and 9.80% within 90 days of follow-up. Compared with those with low LDL and oxLDL levels (LDL 3.37 mmol/L with oxLDL13.96 μg/dL), patients with high levels of LDL and oxLDL (LDL ≥3.37 mmol/L, oxLDL ≥13.96 μg/dL) had significantly increased risk of recurrent stroke at 90 days (HR,1.57; 95% CI, 1.10-2.24) and 1 year (HR,1.49; 95% CI, 1.10-2.04). Patients in groups with LDL ≥3.37 mmol/L, oxLDL13.96 μg/dL (HR,1.35; 95% CI, 0.94-1.93) or LDL 3.37 mmol/L with oxLDL ≥13.96 μg/dL (HR,1.11; 95% CI, 0.77-1.59) showed no statistical difference for stroke recurrence. Similar results were found for functional outcomes.The presence of higher combined serum oxLDL and LDL levels was associated with increased risk of recurrent stroke and poor functional outcomes in minor stroke or high-risk TIA patients.

Pyruvate kinase M2 (PKM2) links metabolic and inflammatory dysfunction in atherosclerotic coronary artery disease; however, its role in oxidized LDL (Ox-LDL)-induced macrophage foam cell formation and inflammation is unknown and therefore was studied. In recombinant mouse granulocyte-macrophage colony-stimulating factor-differentiated murine bone marrow-derived macrophages, early (1-6 h) Ox-LDL treatment induced PKM2 tyrosine 105 phosphorylation and promotes its nuclear localization. PKM2 regulates aerobic glycolysis and inflammation because PKM2 shRNA or Shikonin abrogated Ox-LDL-induced hypoxia-inducible factor-1α target genes lactate dehydrogenase, glucose transporter member 1, interleukin 1β (IL-1β) mRNA expression, lactate, and secretory IL-1β production. PKM2 inhibition significantly increased Ox-LDL-induced ABCA1 and ABCG1 protein expression and NBD-cholesterol efflux to apoA1 and HDL. PKM2 shRNA significantly inhibited Ox-LDL-induced CD36, FASN protein expression, DiI-Ox-LDL binding and uptake, and cellular total cholesterol, free cholesterol, and cholesteryl ester content. Therefore, PKM2 regulates lipid uptake and efflux. DASA-58, a PKM2 activator, downregulated LXR-α, ABCA1, and ABCG1, and augmented FASN and CD36 protein expression. Peritoneal macrophages showed similar results. Ox-LDL induced PKM2- SREBP-1 interaction and FASN expression in a PKM2-dependent manner. Therefore, this study suggests a role for PKM2 in Ox-LDL-induced aerobic glycolysis, inflammation, and macrophage foam cell formation.

Certain microRNAs (miRNA/miRs) serve important roles in the progression of atherosclerosis (AS); however, the exact regulatory mechanisms of miRNAs in AS remain to be fully elucidated. The present study aimed to investigate the effects of miR-125a-5p in AS and the underlying mechanisms. Oxidized low-density lipoprotein (ox-LDL) was employed to stimulate human aortic vascular smooth muscle cells (HAVSMCs) to establish a cell model of AS. Reverse transcription-quantitative PCR was used to determine the expression levels of miR-125a-5p. Cell proliferation was evaluated using a Cell Counting Kit-8 (CCK-8) and migration was detected using a Transwell assay. In addition, the levels of the VSMC-specific marker gene α-smooth muscle actin, the cell cycleregulatory proteins cyclin-dependent kinase (CDK)2, cyclin D1, cyclin E and p27, as well as the migration-associated proteins matrix metalloproteinase-2 (MMP2) and MMP9, and phosphorylated phosphoinositide 3-kinase (p-PI3K) and p-AKT were determined by western blot analysis. The results revealed that transfection of miR-125a-5p mimics inhibited the ox-LDL-induced proliferation of HSVSMCs, accompanied by decreased expression of CDK-2, cyclin D1 and cyclin E, and increased expression of p27. Furthermore, miR-125a-5p mimics attenuated the ox-LDL-induced migration of HAVSMCs in parallel with downregulation of the expression of MMP2 and MMP9. Furthermore, the effect of ox-LDL to increase p-PI3K and p-AKT levels was significantly blunted by miR-125a-5p mimics. In conclusion, the present results suggested that miR-125a-5p mimics inhibited ox-LDL-induced proliferation and migration of HAVSMCs through inhibition of PI3K/AKT signaling, providing a potential novel therapeutic strategy for AS.

Current guidelines recommend administration of high-dose statins in acute coronary syndrome (ACS). It has been reported that statins upregulate proprotein convertase subtilisin kexin 9 (PCSK9) mRNA expression and increase circulating PCSK9 levels. We aimed to compare the effects of high-dose atorvastatin and rosuvastatin on serum oxidized low-density lipoprotein (oxidized-LDL) and PCSK9 levels in statin-naive patients with ACS.One hundred and six patients with ACS were enrolled in this study. The patients were assigned randomly to receive atorvastatin (80 mg/day) or rosuvastatin (40 mg/day) by using a ratio of 1 : 1 in randomization. The levels of total cholesterol (TC), triglyceride, high-density lipoprotein cholesterol, LDL-cholesterol, oxidized-LDL, and PCSK9 were compared between groups after a 4-week treatment.Our study population included 53 patients in the atorvastatin group (age: 58.13±11.30 years, 11.32% female) and 53 patients in the rosuvastatin group (age: 59.08±12.44 years, 15.09% female). In both groups, lipid parameters, oxidized-LDL, and PCSK9 values changed significantly according to the baseline following treatment. High-dose atorvastatin and rosuvastatin induced similar decreases in LDL-cholesterol, oxidized-LDL, and triglyceride levels and similarly increased in high-density lipoprotein cholesterol and PCSK9 levels (P0.05).We showed that atorvastatin and rosuvastatin treatment regimens have comparable effects on lipid parameters and PCSK9 levels in ACS patients.

Purpose Obesity has become a very significant health problem in childhood. Fructose taken in an uncontrolled manner and consumed in excessive amounts is rapidly metabolized in the body and gets converted into fatty acids. This single center prospective case-control study aims to investigate the relationship between fructose consumption and obesity and the role of fructose consumption in development of atherosclerotic diseases. Methods A total of 40 obese and 40 healthy children who were of similar ages (between 8 and 18 years) and sexes were included in the study. In the patient and control groups, the urine fructose levels, as well as the levels of oxidized low-density lipoprotein (LDL), small dense LDL, Apolipoprotein A and Apolipoprotein B values, which have been shown to play a role in development of atherosclerotic diseases, were measured. Results The levels of oxidized LDL and small dense LDL and the ratio of Apolipoprotein A/Apolipoprotein B were found to be significantly higher in the patient group. Conclusion We found that urinary fructose levels were higher in the obese children than the healthy children. Our results suggest that overconsumption of fructose in children triggers atherogenic diseases by increasing the levels of small dense LDL and oxidized LDL and the ratio of Apolipoprotein B/Apolipoprotein A.

BackgroundAtherosclerosis is a risk factor for cardiovascular diseases. However, the roles of Circular RNAs (circRNAs) in atherosclerosis is unknown. Our study aimed to explore the effects of circ_0065149 in the pathogenesis of atherosclerosis.MethodsThe expression of circ_0065149 ox-LDL-induced in human umbilical vein endothelial cells (HUVECs) was assessed by RT-PCR. Cell viability, lactate dehydrogenase leakage, apoptosis, invasion, and migration were assessed in HUVECs. Dual luciferase reporter system was carried out to determine the interaction between miR-330-5p and circ_0065149.ResultsOur results showed that circ_0065149 was significantly lower in the ox-LDL-induced HUVECs. Overexpression of circ_0065149 promoted the cell viability and inhibited the apoptosis of ox-LDL-induced HUVECs. Overexpression of circ_0065149 also promoted the migration and invasion of ox-LDL-induced HUVECs. The expression of miR-330-5p was inhibited by overexpression of circ_0065149. Furthermore, circ_0065149 overexpression significantly inhibited the expressions of nuclear NF-κBp65 and suppressed the production of TNF-α, IL-6, and IL-1β in ox-LDL-induced HUVECs, which was rescued by the miR-330-5p mimic.ConclusionThese findings suggest that circ_0065149 plays an important role in the proliferation, apoptosis, and inflammatory response of HUVECs via targeting miR-330-5p.

Background Serum lipid levels, especially of oxidized low-density lipoprotein (oxLDL), are related to the development of cataracts, but the mechanisms underlying the role of oxLDL in cataract development in human lens epithelial cells (HLEpiCs) remain unclear. Calcium (Ca2+) overload is also known to be involved in lens turbidity. Store-operated Ca2+ entry (SOCE) is an important pathway mediating Ca2+ influx in lens epithelial cells. The Orai family proteins, which form a type of SOCE channel, localize at the plasma membrane and control Ca2+ influx in response to the depletion of Ca2+ stores in the endoplasmic reticulum. Methods In the present study, we used RNA sequencing, western blot analyses, cell proliferation assays, Ca2+ measurements, and small interfering (si)RNA transfections to investigate the effects of oxLDL on SOCE and proliferation of human lens epithelial cells (HLEpiCs). Results The key findings of our study that suggest this conclusion are that (1) oxLDL enhances the expression levels of Orai3, but not Orai1 or Orai2, in HLEpiCs in vitro; (2) oxLDL significantly increases the proliferation of HLEpiCs in a concentration-dependent manner; (3) oxLDL significantly increases ATP-induced SOCE without affecting Ca2+ release in HLEpiCs; and (4) knockdown of Orai3 significantly reduces cell proliferation and ATP-induced SOCE in HLEpiCs. Conclusions These findings suggest that Ca2+ signaling altered by overexpression of Orai3 may be a mechanism whereby oxLDL increases HLEpiC proliferation to contribute to the development of cataract. Thus, Orai3 may be a target warranting development for the treatment of cataract associated with obesity or hyperlipidemia.

Oxidized-low-density lipoprotein (oxLDL) is well-recognized as an actual patho-atherogenic lipoprotein: elevated serum concentration of oxLDL increases the risk for developing atherosclerosis, leading to coronary artery disease (CAD). Herein, we report an approach for sensing oxLDL directly in serum with molecularly imprinted polymer (MIP) thin films on quartz crystal microbalance (QCM). The resulting MIP sensors show low cross-reaction toward low-density lipoprotein (LDL) and high-density lipoprotein (HDL): signals are around one magnitude smaller. Very-low-density lipoprotein (VLDL) and human serum albumin (HSA) do not lead to any significant sensor response. The sensor allowed for accurately assessing oxLDL over the detection range of 86–5600 μg dL−1, which covers the clinically relevant concentrations. The sensor determines oxLDL with recovery accuracy of 92–107% and a precision of 1–8% coefficient variation. Compared with commercially available oxLDL ELISA test kit our sensor reveals similar characteristics obtaining a correlation coefficient of 0.98. However, the sensors have rapid response times of 10 min compared to 210 min of ELISA, which demonstrates their efficiency in assessing this sensitive atherogenic biomarker for CAD diagnostics.

Context:Crataegus aronia (Willd.) Bosc (Rosaceae) (syn. Azarolus L) is traditionally used to treat cardiovascular disorders. Objectives: To investigate C. aronia protection against a high-fat diet (HFD)-induced vascular inflammation in rats. Materials and methods: Wistar Male rats (180–220 g) were divided (n = 10/group) as control fed a standard diet (STD), STD + C. aronia (200 mg/kg, orally), HFD, HFD + C. aronia and HFD post-treated with C. aronia. Simvastatin (20 mg/kg) was co- or post-administered as a positive control drug. HFD was given for 8 weeks, and all other treatments were administered for 4 weeks. Results: Most significantly, co-administration of C. aronia to HFD-fed rats reduced the thickness of aorta tunica media (90 ± 5 vs. 160 ± 11.3 µm) and adventitia (54.3 ± 3.8 vs. 93.6 ± 9.4 µm). It also lowered protein levels of TNF-α (0.51 ± 0.15 and 0.15 ± 0.16 vs. 0.1 ± 0.09%) and IL-6 (0.52 ± 0.19 vs. 1.0 ± 0.2%) in their aorta or serum (5.9 ± 0.91 vs. 12.98 ± 1.3 ng/mL and 78.1 ± 6.7 vs. 439 ± 78 pg/mL, respectively). It also lowered all serum lipids and increased aorta levels of GSH levels (70.4 ± 4.0 vs. 40.7 µM) and activity of SOD (5.7 ± 0.7 vs. 2.9 ± 0.6 U/mg) and decreased serum levels of ox-LDL-c (566.7 ± 46 vs. 1817 ± 147 ng/mL). Such effects were more profound than all other treatments. Conclusions:C. aronia inhibits the HFD-induced vascular inflammation and its use in clinical trials is recommended.

Oxidized low-density lipoprotein (OxLDL) plays a pivotal role in atherosclerotic plaque destabilization, which suggests its potential as a nuclear medical imaging target. We previously developed radioiodinated 125I-AHP7, a peptide probe carrying a 7-residue sequence from the OxLDL-binding protein Asp-hemolysin, for specific OxLDL imaging. Although 125I-AHP7 recognized OxLDL, it had low stability. Thus, to improve stability, we designed radiolabeled 22-residue peptide probes, 125I-AHP22 and 111In-AHP22, which include the entire AHP7 sequence, and evaluated the stability, activity, and applications of these probes in vitro and in vivo. Probes consisting of a 21-residue peptide derived from the Asp-hemolysin sequence and an N-terminal Cys or aminohexanoic acid for labeling with 125I-N-(3-iodophenyl)maleimide or 111In diethylene triamine pentaacetic acid were termed 125I-AHP22 and 111In-AHP22. An in vitro-binding inhibition assay with OxLDL was performed using 125I-AHP7 as a radiotracer. Radioactivity accumulation in the atherosclerotic aorta and plasma intact fraction was evaluated 30 min after intravenous administration of probes in myocardial infarction-prone Watanabe heritable hyperlipidemic (WHHLMI) rabbits. 125I-AHP22 and 111In-AHP22 were synthesized in ~ 360 and 60 min, respectively, with > 98% radiochemical purities after RP-HPLC purification. An in vitro-binding assay revealed similar or greater inhibition of OxLDL binding by both In-AHP22 and I-AHP22 compared to I-AHP7. The fraction of intact 125I-AHP22 and 111In-AHP22 in plasma was estimated to be approximately tenfold higher than that of 125I-AHP7. Both probes were rapidly cleared from the blood. 111In-AHP22 had a 2.3-fold higher accumulation in WHHLMI rabbit aortas compared to control rabbits, which was similar to 125I-AHP7. However, 125I-AHP22 accumulated to similar levels in aortas of WHHLMI and control rabbits due to high nonspecific accumulation in normal aortas that could be due to high lipophilicity. 111In-AHP22, easily prepared within 1 h, showed moderate affinity for OxLDL, high stability in vivo, and high accumulation in atherosclerotic aortas. 111In-AHP22 could be a potential lead compound to develop future effective OxLDL imaging probes.

Solution acidification exists under some physiological conditions (e.g. lysosomes in cells) and diseases (e.g. atherosclerosis, tumors, etc.). It is poorly understood whether and how acidification influences the size and biomechanical (stiffness and stickiness) properties of native Low-density lipoprotein (LDL) and its oxidized form (oxLDL) which plays a vital role in atherogenesis and tumorigenesis. Atomic force microscopy (AFM) evaluated that gradient acidification from pH 7.4 to pH 4.4 caused an expanding-first-and-then-shrinking decrease in size and a dramatic decrease in stiffness (but no statistically significant changes in stickiness) of LDL/oxLDL particles by influencing secondary/tertiary structures and lipid release detected by infrared spectral analysis and cholesterol detection, respectively. The smaller and softer characteristics of LDL/oxLDL at acidic conditions versus at the neutral pH partially explains the atherogenic role of acidification. The data may provide important information for a better understanding of LDL/oxLDL and some diseases (e.g. atherosclerosis and tumors).

Raman spectroscopic imaging was used to investigate the uptake of oxidized LDLs (oxLDLs) by human macrophages. To better understand the endocytic pathway and the intracellular fate of modified lipoproteins is of foremost interest with regard to the development of atherosclerotic plaques. To obtain information on the storage process of lipids caused by oxLDL uptake, Raman spectroscopic imaging was used because of its unique chemical specificity, especially for lipids. For the present study, a protocol was established to incorporate deuterated tripalmitate into oxLDL. Subsequently, human THP-1 macrophages were incubated for different time points and their chemical composition was analyzed using Raman spectroscopic imaging. β-Carotene was found to be a reliable marker molecule for the uptake of lipoproteins into macrophages. In addition, lipoprotein administration led to small endocytic vesicles with different concentrations of deuterated lipids within the cells. For the first time, the translocation of deuterated lipids from endocytic vesicles into lipid droplets over time is reported in mature human THP-1 macrophages.

The correct name of the 17th Author is presented in this paper. In the paragraph “Metabolic analysis” of the Method section “an XFp Analyzer” should be changed to “an XFe96 Analyzer”.

Atherosclerosis is characterized as a chronic inflammatory response to cholesterol deposition in arteries. Low-density lipoprotein (LDL), especially the oxidized form (ox-LDL), plays a crucial role in the occurrence and development of atherosclerosis by inducing endothelial cell (EC) dysfunction, attracting monocyte-derived macrophages, and promoting chronic inflammation. However, the mechanisms linking cholesterol accumulation with inflammation in macrophage foam cells are poorly understood. Long non-coding RNAs (lncRNAs) are a group of non-protein-coding RNAs longer than 200 nucleotides and are found to regulate the progress of atherosclerosis. Recently, many lncRNAs interfering with cholesterol deposition or inflammation were identified, which might help elucidate their underlying molecular mechanism or be used as novel therapeutic targets. In this review, we summarize and highlight the role of lncRNAs linking cholesterol (mainly ox-LDL) accumulation with inflammation in macrophages during the process of atherosclerosis.

Introduction: Metabolic stress including oxidized low density lipoprotein (ox-LDL) and angiotensin II (AngII) cause mitochondrial dysfunction and vascular senescence. Mitochondria are highly dynamic organelles that constantly change their morphology to fusion or fission. This study aims to clarify how mitochondrial dynamics are involved in the etiology of vascular senescence. Methods: VSMC and HUVEC were stimulated by either ox-LDL or AngII. We also conducted in vivo experiment using C57BL6 (WT), apolipoprotein E (ApoE) deficient and the double knockout of ApoE and AT1R (DKO) mice. Results: Either ox-LDL or AngII induced excessive mitochondrial fission though phosphorylation of Drp1 at Ser616, mitochondrial dysfunction assessed by JC1, reactive oxygen species production measured with Mito-Sox Red and Amplex assay and cellular senescence analyzed by senescence associated beta galactosidase staining and immunoblot of p53 and p21 in cells. Administration of mdivi-1, a specific inhibitor of Drp1, restored imbalance of mitochondrial dynamics and these detrimental alterations. Treatment with angiotensin II type1 receptor (AT1R) inhibitor also inactivated Drp1 and improved imbalance of mitochondrial dynamics, mitochondrial dysfunction and cellular senescence. These results suggest that ox-LDL- or AngII-induced mitochondrial dysfunction and cellular senescence were derived from Drp1-dependent mitochondrial fission. Administration of AT1R inhibitor to HUVEC or SMC with ox-LDL prevented cells against excessive mitochondrial fission, its dysfunction and cellular senescence. The degree of vascular senescence was higher, the number of fused mitochondria and mitochondrial function were lower and mitochondrial oxidative stress were higher in either C57BL6 with AngII infusion or ApoE KO mice than those of control or WT mice, respectively. Treatment with mdivi-1 to these mice reduced mitochondrial fission, oxidative stress and attenuated vascular senescence. The number of fused mitochondria and its function were higher and the degree of vascular senescence were lower in DKO than those in ApoE KO mice. Conclusion: Either ox-LDL or AngIIcauses cellular and vascular senescence through AT1R signal-mediated mitochondrial fission.

The development of new methods to assess biomarkers of cardiovascular disease is currently a subject of scientific research. This article broadens our view of nonlinear optical responses of oxidized low density lipoprotein (LDL) evaluated using the Z-scan peak-valley distance and proposes a cutoff point. We investigated the association of peak-valley distance and some cardiovascular risk factors related with sociodemographic, clinical and anthropometric profiles and plasma biomarkers such as lipid and glucose profile, apolipoprotein, lipoprotein subfractions and omega 3 fatty acids. Z-scan analysis was performed using isolated LDL after ultracentrifugation in human blood samples collected after fasting. Peak-valley distance is a parameter that decreases directly depending on the oxidizability of LDL. As peak-valley distance was associated with relevant biomarkers of cardiovascular risk, we tested cutoff points for categorization and the best results were obtained using percentile

Background Lipid peroxidation and oxidized LDL (oxLDL) are hallmarks in the development of various metabolic, cardiovascular and other inflammatory diseases. Cholesterol crystals and oxLDL, which are considerably present in atherosclerotic plaques, can activate inflammasomes. The concentration of plasma ox-LDL was also closely associated with the high incidence of atherosclerotic diseases in patients with gout might be closely related to increased ox-LDL levels. However, the study about the relationship between the level of ox-LDL and the inflammatory status in gout patients are rare. Objectives We aimed to the relationships between ox-LDL level, inflammatory markers and uric acid lowering agents in gout patients. Methods One hundred seventy four gout patients were included from the 3 institutions from 2014 to 2017. Details of demographic and clinical features along with laboratory parameters, ESR, CRP, lipid profiles, oxLDL and disease status were noted in patients with gout. We classified inflammatory status as acute, subacute chronic tophaceous and well controlled status. The level of ox-LDL was measured using the latex enhanced immune transmission turbidimetric method. We analyzed the comparison between dermographics, inflammatory markers, lipid profiles and disease subset. Results The primary objective of this study was to assess the oxLDL according to inflammatory status in gouty arthritis. Mean age was 50.4 year-old, 85.7% was woman, 98.9% were male, mean BMI was 25.86 and mean disease duration was 48 months. Among 174 gout patients, 61 patients (35.1%) were acute flare-up, 38 patients (21.8%) were subacute, 67 patients (38.5%) were chronic tophaceous, and 7 patients (4%) were well controlled stable status. Age, sex, BMI, and accompanying disease were not statistically different in the 4 groups according to inflammatory status. However, it showed statistically significant differences in the use of glucocorticoid and uric acid lowering agents. There was no significant difference in uric acid in laboratory tests, but there was a significant difference between ESR and CRP in each disease group. Especially, oxLDL showed difference according to inflammatory state of disease. Conclusion The levels of oxLDL in gout patients were significantly different according to inflammatory status. The oxLDL may be associated with inflammation process in gout patients. Disclosure of Interests None declared

It has been demonstrated that pitavastatin can significantly reduce low-density lipoprotein (LDL) cholesterol (LDL-C), but its impact on lipoprotein subfractions and oxidized low-density lipoprotein (oxLDL) has not been determined. The aim of the present study was to investigate the potential effects of pitavastatin on subfractions of LDL and high-density lipoprotein (HDL) as well as oxLDL in untreated patients with coronary atherosclerosis (AS). Thirty-six subjects were enrolled in this study. Of them, 18 patients with AS were administered pitavastatin 2 mg/day for 8 weeks and 18 healthy subjects without therapy served as controls. The plasma lipid profile, lipoprotein subfractions and circulating oxLDL were determined at baseline and 8 weeks respectively. The results showed that pitavastatin treatment indeed not only decreased LDL-C, total cholesterol (TC), triglycerides (TG) and apolipoprotein B (ApoB) levels, and increased HDL cholesterol (HDL-C), but also reduced the cholesterol concentration of all of the LDL subfractions and the percentage of intermediate and small LDL subfractions. Meanwhile, pitavastatin could decrease plasma oxLDL levels. Furthermore, a more close correlation was found between oxLDL and LDL-C as well as LDL subfractions after pitavastatin treatment. We concluded that a moderate dose of pitavastatin therapy not only decreases LDL-C and oxLDL concentrations but also improves LDL subfractions in patients with AS.

Objective: To estimate the association of different combination of circulating LDL and oxLDL levels with the outcomes of acute minor ischemic stroke and transient ischemic attack (TIA). Methods: In the Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events (CHANCE) trial, a subgroup of 3019 patients with elevated baseline oxLDL and LDL levels were analyzed. Patients were divided into four groups according to different combination of LDL and oxLDL levels. The associations of LDL and oxLDL with prognosis of patients using multivariable Cox regression models. Results: Among 3019 patients included in this study, the median (interquartile range) of oxLDL, and LDL were 13.96 (6.65-28.81) ug/dL, 3.1(2.5-3.8) mmol/L, respectively. Compared with those with low LDL and oxLDL levels (LDL < 3.37mmol/L with oxLDL Conclusions: Presence of both elevated oxLDL and LDL levels can predict an increased risk of recurrent stroke and poor functional outcome in minor stroke or high- risk TIA patients. The presence of both oxLDL and LDL might have a combined effect.

Oxidized low density lipoprotein (oxLDL)-induced apoptosis of macrophages contributes to the formation of atherosclerotic plaques. R-spondin 2 (Rspo2), a member of the cysteine-rich secreted proteins, has been shown to be involved in the oncogenesis of several types of cancer. It has also been found to be abundantly expressed among the four R-spondin members in macrophages. The present study was performed to determine whether Rspo2 is involved in the ox-LDL-induced apoptosis of macrophages. It was identified that Rspo2 inhibited oxLDL-induced apoptosis in the presence of endoplasmic reticulum (ER) stress activator using flow cytometry. In addition, Rspo2 was observed to suppress oxLDL-induced ER stress and reactive oxygen species production as demonstrated by western blotting. Furthermore, analysis of the role of Rspo2 in macrophage lipid uptake identified that Rspo2 negatively regulated the Dil-oxLDL uptake by inhibiting the expression of cluster of differentiation (CD)36, through the transcription factor, peroxisome proliferator-activated receptor (PPAR)-γ. The manipulation of Rspo2 had a direct effect on PPAR-γ nuclear translocation. In addition, chromatin immunoprecipitation analysis revealed that Rspo2 manipulation led to regulation of the direct binding between PPAR-γ and CD36. In conclusion, Rspo2 was found to have a negative regulatory effect during oxLDL-induced macrophage apoptosis by regulating lipid uptake.

Background and aims: The oxidation of low-density lipoprotein (LDL) cholesterol particles is an early atherogeninic event. Obese pediatric populations have higher levels of oxidized LDL (oxLDL) than normal weight children. The aim of this study was to evaluate the effect of a weight loss program on the biochemical profile and oxLDL levels in Spanish obese children and adolescents. Methods: Forty obese children (mean age 11 years, 51% boys) followed a 10-week weight loss program. They were dichotomized at the median of body mass index-standard deviation score (BMI-SDS) change, as high (HR) and low responders (LR) after the intervention. The intervention included a moderate energy-restricted diet, nutritional education, and family involvement. Anthropometric and biochemical measurements were performed at the beginning and during the follow up. A cardiometabolic risk score (CMS) was calculated considering metabolic risk factors. Results: Higher baseline oxLDL levels were associated with a higher CMS in obese children (P (Less)

The endothelial-to-mesenchymal transition (EndMT) of endothelial cells contributes to the development of atherosclerosis. Oxidized low density lipoprotein (ox-LDL) is a highly risk factor for atherosclerosis. However, whether ox-LDL causes EndMT and the underlying mechanism are unclear. We report here that ox-LDL treatment is able to induce EndMT in human aortic endothelial cells (HAECs), and that the ox-LDL-induced EndMT is strictly dependent on the presence of its innate receptor, ox-LDL Receptor-1 (LOX-1). In addition, ox-LDL specifically upregulates EndMT transcriptional factor Snail, and knockdown of Snail completely attenuates ox-LDL-induced EndMT, indicating an essential role of Snail in mediating this effect. Mechanically, ox-LDL induces Snail stabilization by inhibiting its ubiquitination, which is in part attributed to inhibited GSK-3β activity. Hence, our findings suggest that inducing EndMT of aortic endothelial cells by ox-LDL might contribute to its detrimental role in promoting atherosclerosis development.

We provide an up-to-date overview of current topics surrounding oxidized low-density lipoprotein (oxLDL) and its related antibodies in the quest to better identify the individuals at risk of cardiovascular disease and atherosclerotic plaques with unfavorable characteristics. We discuss the potential of oxLDL and anti-oxLDL antibodies as serum biomarkers of cardiovascular disease and emerging studies examining the targeting of arterial oxLDL for imaging and therapeutic delivery.

Background Propolis, a polyphenol-rich natural product, has been used as a functional food in anti-inflammation. However, its bioactive components and mechanisms have not been fully elucidated. To discover the bioactive components and anti-inflammatory mechanism, we prepared and separated 8 subfractions from ethyl acetate extract of Chinese propolis (EACP) and investigated the mechanism in oxidized low density lipoprotein (ox-LDL) induced human umbilical vein endothelial cells (HUVECs) damage. Methods Eight subfractions were prepared and separated from ethyl acetate extract of Chinese propolis (EACP) with different concentrations of methanol-water solution, and analysed its chemical constituents by HPLC-DAD/Q-TOF-MS. Then 80% confluent HUVECs were stimulated with 40 μg/mL ox-LDL. Cell viability and apoptosis were evaluated by Sulforhodamine B (SRB) assay and Hoechst 33,258 staining, respectively. Levels of caspase 3, PARP, LC3B, p62, p-mTOR, p-p70S6K, p-PI3K, p-Akt, LOX-1 and p-p38 MAPK were assessed by western blotting and immunofluorescence assay, respectively. Reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were measured with fluorescent probes. Results Each subfraction exhibited similar protective effect although the contents of chemical constituents were different. EACP attenuated ox-LDL induced HUVECs apoptosis, depressed the ratio of LC3-II/LC3-I and enhanced the p62 level. In addition, treatment with EACP also activated the phosphorylation of PI3K/Akt/mTOR, and deactivated the level of LOX-1 and phosphorylation of p38 MAPK. The overproduction of ROS and the damage of MMP were also ameliorated after ECAP treatment. Conclusions These findings indicated that the bioactive component of propolis on anti-inflammatory activity was not determined by a single constituent, but a complex interaction including flavonoids, esters and phenolic acids. EACP attenuated ox-LDL induced HUVECs injury by inhibiting LOX-1 level and depressed ROS production against oxidative stress in ox-LDL induced HUVECs, further to activate PI3K/Akt/mTOR pathway and deactivate p38 MAPK to inhibit apoptosis and autophagy, which provide novel insights into the potential application of propolis on modulating chronic inflammation.

Introduction: Lectin-like oxidized low density lipoprotein receptor 1 (LOX-1, SREC-1, OLR1) is a class E scavenger receptor which binds oxidized low density lipoprotein (oxLDL) particles implicated in promoting atherosclerosis. Affimers are non-antibody synthetic protein-based scaffolds that enable recognition of a wide range of molecular targets. Aims: To investigate the ability of Affimers to bind LOX-1 and modulate oxLDL accumulation and effects on cellular responses. Methods: Recombinant soluble human LOX-1 was screened with an Affimer library and LOX-1-specific Affimers were isolated and characterized. Human embryonic kidney (HEK293T) cells inducibly expressing human LOX-1 were incubated with labeled oxLDL and Affimers to modulate LOX-1 and oxLDL uptake and trafficking. Furthermore, Affimer-mediated effects on oxLDL-regulated metabolism and apoptosis was evaluated. Results: Five Affimers specific for human LOX-1 were identified. Fluorescent labelled Affimers demonstrate specific binding to LOX-1 expressing HEK293T cells and modulate LOX-1 and oxLDL trafficking and accumulation in endosomes and lysosomes. LOX-1-specific Affimers also show effects in modulating oxLDL-mediated effects in specific cellular responses. Conclusion: LOX-1-specific Affimers are a new class of synthetic molecules that have therapeutic potential in targeting LOX-1, a key mediator of inflammation and arterial dysfunction in cardiovascular disease. Membrane specific binding is demonstrated only in induced LOX-1 expressing cells (LOX+). Increasing concentration of affimer prior to incubation with DiI labelled oxLDL.

A previous study has revealed that oxidized low‑density lipoprotein (oxLDL)/β2‑glycoprotein I (β2GPI)/anti‑β2‑glycoprotein I (anti‑β2GPI), an immune complex, is able to activate the Toll‑like receptor 4 (TLR4)/nuclear factor κβ (NF‑κβ) inflammatory signaling pathway in macrophages, and consequently enhance foam cell formation and the secretion of prothrombin activators. However, the effects of the oxLDL/β2GPI/anti‑β2GPI complex on vascular smooth muscle cells have yet to be investigated. The present study investigated whether the oxLDL/β2GPI/anti‑β2GPI complex was able to reinforce the pro‑atherogenic activities of a rat thoracic aorta smooth muscle cell line (A7r5) and examined the underlying molecular mechanisms. The results revealed that the oxLDL/β2GPI/anti‑β2GPI complex treatment significantly (P

A novel liquid chromatography-mass spectrometry (LC-MS) approach for analysis of oxidized phosphatidylcholines by an Orbitrap Fourier Transform mass spectrometer in positive electrospray ionization (ESI) coupled to hydrophilic interaction liquid chromatography (HILIC) was developed. This method depends on three selectivity criteria for separation and identification: retention time, exact mass at a resolution of 100,000 and collision induced dissociation (CID) fragment spectra in a linear ion trap. The process of chromatography development showed the best separation properties with a silica-based Kinetex column. This type of chromatography was able to separate all major lipid classes expected in mammalian samples, yielding increased sensitivity of oxidized phosphatidylcholines over reversed phase chromatography. Identification of molecular species was achieved by exact mass on intact molecular ions and CID tandem mass spectra containing characteristic fragments. Due to a lack of commercially available standards, method development was performed with copper induced oxidation products of palmitoyl-arachidonoyl-phosphatidylcholine, which resulted in a plethora of lipid species oxidized at the arachidonoyl moiety. Validation of the method was done with copper oxidized human low-density lipoprotein (LDL) prepared by ultracentrifugation. In these LDL samples we could identify 46 oxidized molecular phosphatidylcholine species out of 99 possible candidates.

IF 4.810; International audience; The functional heterogeneity of HDL is attributed to its diverse bioactive components. We evaluated whether the vasodilatory effects of HDL differed across HDL subpopulations, reflecting their distinct molecular composition. The capacity of five major HDL subfractions to counteract the inhibitory effects of oxidized LDL on acetylcholine-induced vasodilation was tested in a rabbit aortic rings model. NO production, an essential pathway in endothelium-dependent vasorelaxation, was studied in simian vacuolating virus 40-transformed murine endothelial cells (SVECs). Small dense HDL3 subfractions displayed potent vasorelaxing activity (up to +31% vs. baseline, P < 0.05); in contrast, large light HDL2 did not induce aortic-ring relaxation when compared on a total protein basis. HDL3 particles were enriched with sphingosine-1-phosphate (S1P) (up to 3-fold vs. HDL2), with the highest content in HDL3b and -3c that concomitantly revealed the strongest vasorelaxing properties. NO generation was enhanced by HDL3c in SVECs (1.5-fold, P < 0.01), a phenomenon that was blocked by the S1P receptor antagonist, VPC 23019. S1P-enriched reconstituted HDL (rHDL) was a 1.8-fold (P < 0.01) more potent vasorelaxant than control rHDL in aortic rings. Small dense HDL3 particles displayed potent protective effects against oxidative stress-associated endothelium dysfunction, potentially reflecting their elevated content of S1P that might facilitate interaction with S1P receptors and ensuing NO generation.

Background Atherosclerosis is a common cardiovascular disease that causes myocardial infarction, heart failure, and stroke. Increased oxidized low density lipoprotein (ox-LDL) in the sub-endothelium is the characteristic origin of atherogenesis. Klotho, an anti-aging protein, has been reported to protect against atherosclerosis and ameliorate endothelial dysfunction in vivo. The aim of this study is to investigatethe anti-oxidative activity of Klothoin ox-LDL-treated human umbilical vein endothelial cells (HUVECs). Methods After pre-treatment with 200 pMKlotho for 1 h, HUVECs were stimulated with 50 μg/ml ox-LDL for 24 h. Reactive oxygen species (ROS) and superoxide dismutase (SOD) levels were analyzed in the cells. Nitric oxide (NO) concertation was measured in the medium supernatant. Related proteins or genes were detected with Western blot or real time PCR, respectively, in the cell lysates. Results Initially, oxidative damage in HUVECs was established by adding 50 μg/mL ox-LDL, which resulted in decreased cellular viability, SOD/Cu/Zn-SOD and endothelial NO synthase (eNOS) expression and NO production, as well as increased malondialdehyde (MDA) levels, ROS production, inducible NO synthase (iNOS), phosphatidyl inositol-3 kinase (PI3K), protein kinase B (Akt), gp91 phox, and lectin-like ox-LDL receptor (LOX-1) expression in HUVECs. Pre-incubation with recombinant Klotho (200 pM) significantly prevented all of these alterations. These results suggest that Klotho can attenuate ox-LDL-induced oxidative stress in HUVECs through upregulating oxidative scavengers (SOD and NO) viaactivating the PI3K/Akt/eNOS pathway and depressing LOX-1expression. Conclusions These results suggest that Klotho has a potential therapeutic effect on attenuating endothelial dysfunction and ameliorating atherosclerosis. Electronic supplementary material The online version of this article (doi:10.1186/s12944-017-0447-0) contains supplementary material, which is available to authorized users.

Scavenger receptor-mediated uptake of oxidized LDL (oxLDL) is thought to be the major mechanism of foam cell generation in atherosclerotic lesions. Recent data has indicated that native LDL is also capable of contributing to foam cell formation via low-affinity receptor-independent LDL particle pinocytosis and selective cholesteryl ester (CE) uptake. In the current investigation, Cu(2+)-induced LDL oxidation was found to inhibit macrophage selective CE uptake. Impairment of selective CE uptake was significant with LDL oxidized for as little as 30 min and correlated with oxidative fragmentation of apoB. In contrast, LDL aggregation, LDL CE oxidation, and the enhancement of scavenger receptor-mediated LDL particle uptake required at least 3 h of oxidation. Selective CE uptake did not require expression of the LDL receptor (LDL-R) and was inhibited similarly by LDL oxidation in LDL-R(-/-) versus WT macrophages. Inhibition of selective uptake was also observed when cells were pretreated or cotreated with minimally oxidized LDL, indicating a direct inhibitory effect of this oxLDL on macrophages. Consistent with the effect on LDL CE uptake, minimal LDL oxidation almost completely prevented LDL-induced foam cell formation. These data demonstrate a novel inhibitory effect of mildly oxidized LDL that may reduce foam cell formation in atherosclerosis.

One hundred and eighteen (118) subjects aged 15 to 36 years divided into control subjects (AA n = 42), heterozygous sickle cell patients (AS n = 33) and homozygous sickle cell patients (SS n = 43) were investigated for a lipid profile including the measurement of oxidized low density lipoprotein (LDL) to assess the risk of early atherosclerosis in sickle cell disease. The results show that total, high density lipoprotein (HDL) and LDL plasma cholesterol levels are significantly lower in the sickle cell patients than in control group (p < 0.05). In contrast, the triglyceride levels, the ratio of triglycerides to HDL-cholesterol and the oxidized LDL fraction are higher in patients (p < 0.05). These lipid abnormalities could represent a cardiovascular risk for sickle cell disease patients. Key words: Atherosclerosis, dyslipidemia, oxidized low density lipoprotein (LDL), sickle cell disease.