High-density lipoprotein infusion therapy: A review.

Increased cholesterol-rich, low-density, non-calcified atheromas as assessed by computer coronary tomography angiography analyses have been shown to predict myocardial infarction significantly better than coronary artery calcium score or the presence of obstructive coronary artery disease (CAD) as evaluated with standard coronary angiography. Low serum high-density lipoprotein (HDL) cholesterol values are an independent risk factor for CAD. Very small, lipid-poor preß-1 HDL particles have been shown to be most effective in promoting cellular cholesterol efflux. HDL infusions have been documented to reduce aortic atherosclerosis in cholesterol-fed animal models. However, human studies using infusions of either the HDL mimetic containing recombinant apolipoprotein (apo) A-I Milano or Cerenis Compound-001 with native recombinant apoA-I have been mainly negative in promoting coronary atherosclerosis progression as assessed by intravascular ultrasound. In contrast, a study using 7 weekly infusions of autologous delipidated HDL in six homozygous familial hypercholesterolemic patients was effective in promoting significant regression of low-density non-calcified coronary atheroma regression as assessed by computed coronary angiography. This therapy has received Food and Drug Administration approval. Commonwealth Serum Laboratories has carried out a large clinical endpoint trial using an HDL complex (native apoA-I with phospholipid), and the results were negative. Our purpose is to review animal and human studies using various forms of HDL infusion therapy to promote regression of atherosclerosis. In our view, differences in results may be due to: 1) the HDL preparations used, 2) the subjects studied, and 3) the methods used to assess coronary atherosclerosis.

Small High-Density Lipoprotein and Omega-3 Fatty Acid Intake Differentiates Japanese and Japanese-Americans: The INTERLIPID Study.

AIM: To identify the most differentiated serum lipids, especially concerning particle size and fractions, between Japanese living in Japan and Japanese-Americans in Hawaii, in the absence of possible genetic confounders, and cross-sectionally examine the associated modifiable lifestyle factors. METHODS: Overall, 1,241 (aged 40-59 years) Japanese living in Japan and Japanese-Americans in Hawaii were included. We quantified 130 serum lipid profiles (VLDL 1-5, IDL, LDL 1-6, high-density lipoprotein [HDL] 1-4, and their subfractions) using Bruker's 1H-nuclear magnetic resonance spectrometer for the primary outcome. Modifiable lifestyle factors included body mass index (BMI), physical activity, alcohol and smoking habits, and 70 nutrient parameters. We evaluated the different lipids between the groups using partial least squares-discriminant analysis and association between extracted lipids and lifestyle factors using multivariable linear regression analysis. RESULTS: Concentrations of HDL4, HDL with the smallest particle size, were lower in Japanese than in Japanese-Americans of both sexes. Higher fish-derived omega-3 fatty acid intake and lower alcohol intake were associated with lower HDL4 concentrations. A 1% higher kcal intake of total omega-3 fatty acids was associated with a 9.8-mg/dL lower HDL4. Fish-derived docosapentaenoic acid, eicosapentaenoic acid, and docosahexaenoic acid intake were inversely associated with HDL4 concentration. There was no relationship between country, sex, age, or BMI. CONCLUSIONS: Japanese and Japanese-Americans can be differentiated based on HDL4 concentration. High fish intake among the Japanese may contribute to their lower HDL4 concentration. Thus, HDL particle size may be an important clinical marker for coronary artery diseases or a fish consumption biomarker.

Phospholipid nanoparticles: Therapeutic potentials against atherosclerosis via reducing cholesterol crystals and inhibiting inflammation.

BACKGROUND: Atherosclerosis-related cardiovascular diseases (CVDs) are the leading cause of mortality worldwide. Cholesterol crystals (CCs) induce inflammation in atherosclerosis and are associated with unstable plaques and poor prognosis, but no drug can remove CCs in the clinic currently. METHODS: We generated a phospholipid-based and high-density lipoprotein (HDL)-like nanoparticle, miNano, and determined CC-dissolving capacity, cholesterol efflux property, and anti-inflammation effects of miNano in vitro. Both normal C57BL/6J and Apoe-deficient mice were used to explore the accumulation of miNano in atherosclerotic plaques. The efficacy and safety of miNano administration to treat atherosclerosis were evaluated in the Ldlr-deficient atherosclerosis model. The CC-dissolving capacity of miNano was also detected using human atherosclerotic plaques ex vivo. FINDINGS: We found that miNano bound to and dissolved CCs efficiently in vitro, and miNano accumulated in atherosclerotic plaques, co-localized with CCs and macrophages in vivo. Administration of miNano inhibited atherosclerosis and improved plaque stability by reducing CCs and macrophages in Ldlr-deficient mice with favorable safety profiles. In macrophages, miNano prevented foam cell formation by enhancing cholesterol efflux and suppressed inflammatory responses via inhibiting TLR4-NF-κB pathway. Finally, in an ex vivo experiment, miNano effectively dissolved CCs in human aortic atherosclerotic plaques. INTERPRETATION: Together, our work finds that phospholipid-based and HDL-like nanoparticle, miNano, has the potential to treat atherosclerosis by targeting CCs and stabilizing plaques. FUNDING: This work was supported by the National Institutes of Health HL134569, HL109916, HL136231, and HL137214 to Y.E.C, HL138139 to J.Z., R21NS111191 to A.S., by the American Heart Association 15SDG24470155, Grant Awards (U068144 from Bio-interfaces and G024404 from M-BRISC) at the University of Michigan to Y.G., by the American Heart Association 19PRE34400017 and Rackham Helen Wu award to M.Y., NIH T32 GM07767 to K. H., Barbour Fellowship to D.L.

Lack of Neuroprotective Effects of High-Density Lipoprotein Therapy in Stroke under Acute Hyperglycemic Conditions.

INTRODUCTION: The pleiotropic protective effects of high-density lipoproteins (HDLs) on cerebral ischemia have never been tested under acute hyperglycemic conditions. The aim of this study is to evaluate the potential neuroprotective effect of HDL intracarotid injection in a mouse model of middle cerebral artery occlusion (MCAO) under hyperglycemic conditions. METHODS: Forty-two mice were randomized to receive either an intracarotid injection of HDLs or saline. Acute hyperglycemia was induced by an intraperitoneal injection of glucose (2.2 g/kg) 20 min before MCAO. Infarct size (2,3,5-triphenyltetrazolium chloride (TTC)-staining), blood-brain barrier leakage (IgG infiltration), and hemorrhagic changes (hemoglobin assay by ELISA and hemorrhagic transformation score) were analyzed 24 h post-stroke. Brain tissue inflammation (IL-6 by ELISA, neutrophil infiltration and myeloperoxidase by immunohisto-fluorescence) and apoptosis (caspase 3 activation) were also assessed. RESULTS: Intraperitoneal D-glucose injection allowed HDL- and saline-treated groups to reach a blood glucose level of 300 mg/dl in the acute phase of cerebral ischemia. HDL injection did not significantly reduce mortality (19% versus 29% in the saline-injected group) or cerebral infarct size (p = 0.25). Hemorrhagic transformations and inflammation parameters were not different between the two groups. In addition, HDL did not inhibit apoptosis under acute hyperglycemic conditions. Conclusion: We observed a nonsignificant decrease in cerebral infarct size in the HDL group. The deleterious consequences of reperfusion such as hemorrhagic transformation or inflammation were not improved by HDL infusion. In acute hyperglycemia, HDLs are not potent enough to counteract the adverse effects of hyperglycemia. The addition of antioxidants to therapeutic HDLs could improve their neuroprotective capacity.

MEDI6012: Recombinant Human Lecithin Cholesterol Acyltransferase, High-Density Lipoprotein, and Low-Density Lipoprotein Receptor-Mediated Reverse Cholesterol Transport.

Background MEDI6012 is recombinant human lecithin cholesterol acyltransferase, the rate-limiting enzyme in reverse cholesterol transport. Infusions of lecithin cholesterol acyltransferase have the potential to enhance reverse cholesterol transport and benefit patients with coronary heart disease. The purpose of this study was to test the safety, pharmacokinetic, and pharmacodynamic profile of MEDI6012. Methods and Results This phase 2a double-blind study randomized 48 subjects with stable coronary heart disease on a statin to a single dose of MEDI6012 or placebo (6:2) (NCT02601560) with ascending doses administered intravenously (24, 80, 240, and 800 mg) and subcutaneously (80 and 600 mg). MEDI6012 demonstrated rates of treatment-emergent adverse events that were similar to those of placebo. Dose-dependent increases in high-density lipoprotein cholesterol were observed with area under the concentration-time curves from 0 to 96 hours of 728, 1640, 3035, and 5318 should be: mg·h/mL in the intravenous dose groups and 422 and 2845 mg·h/mL in the subcutaneous dose groups. Peak mean high-density lipoprotein cholesterol percent change was 31.4%, 71.4%, 125%, and 177.8% in the intravenous dose groups and 18.3% and 111.2% in the subcutaneous dose groups, and was accompanied by increases in endogenous apoA1 (apolipoprotein A1) and non-ATP-binding cassette transporter A1 cholesterol efflux capacity. Decreases in apoB (apolipoprotein B) were observed across all dose levels and decreases in atherogenic small low-density lipoprotein particles by 41%, 88%, and 79% at the 80-, 240-, and 800-mg IV doses, respectively. Conclusions MEDI6012 demonstrated an acceptable safety profile and increased high-density lipoprotein cholesterol, endogenous apoA1, and non-ATP-binding cassette transporter A1 cholesterol efflux capacity while reducing the number of atherogenic low-density lipoprotein particles. These findings are supportive of enhanced reverse cholesterol transport and a functional high-density lipoprotein phenotype. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02601560.

HDL Improves Cholesterol and Glucose Homeostasis and Reduces Atherosclerosis in Diabetes-Associated Atherosclerosis.

BACKGROUND AND AIMS: Apolipoprotein A-I (ApoA-I), the main component of high-density lipoprotein (HDL), not only promotes reverse cholesterol transport (RCT) in atherosclerosis but also increases insulin secretion in pancreatic ß-cells, suggesting that interventions which raise HDL levels may be beneficial in diabetes-associated cardiovascular disease (CVD). Previously, we showed that TNF-related apoptosis-inducing ligand (TRAIL) deletion in Apolipoprotein Eknockout (Apoe-/- ) mice results in diabetes-accelerated atherosclerosis in response to a "Western" diet. Here, we sought to identify whether reconstituted HDL (rHDL) could improve features of diabetes-associated CVD in Trail-/-Apoe-/- mice. METHODS AND RESULTS: Trail-/-Apoe-/- and Apoe-/- mice on a "Western" diet for 12 weeks received 3 weekly infusions of either PBS (vehicle) or rHDL (containing ApoA-I (20 mg/kg) and 1-palmitoyl-2-linoleoyl phosphatidylcholine). Administration of rHDL reduced total plasma cholesterol, triglyceride, and glucose levels in Trail-/-Apoe-/- but not in Apoe-/- mice, with no change in weight gain observed. rHDL treatment also improved glucose clearance in response to insulin and glucose tolerance tests. Immunohistological analysis of pancreata revealed increased insulin expression/production and a reduction in macrophage infiltration in mice with TRAIL deletion. Furthermore, atherosclerotic plaque size in Trail-/-Apoe-/- mice was significantly reduced associating with increased expression of the M2 macrophage marker CD206, suggesting HDL's involvement in the polarization of macrophages. rHDL also increased vascular mRNA expression of RCT transporters, ABCA1 and ABCG1, in Trail-/-Apoe-/- but not in Apoe-/- mice. Conclusions. rHDL improves features of diabetes-associated atherosclerosis in mice. These findings support the therapeutic potential of rHDL in the treatment of atherosclerosis and associated diabetic complications. More studies are warranted to understand rHDL's mechanism of action.

HDL biodistribution and brain receptors in zebrafish, using HDLs as vectors for targeting endothelial cells and neural progenitors.

High density lipoproteins (HDLs) display pleiotropic functions such as anti-inflammatory, antioxidant, anti-protease, and anti-apoptotic properties. These effects are mediated by four main receptors: SCARB1 (SR-BI), ABCA1, ABCG1, and CD36. Recently, HDLs have emerged for their potential involvement in brain functions, considering their epidemiological links with cognition, depression, and brain plasticity. However, their role in the brain is not well understood. Given that the zebrafish is a well-recognized model for studying brain plasticity, metabolic disorders, and apolipoproteins, it could represent a good model for investigating the role of HDLs in brain homeostasis. By analyzing RNA sequencing data sets and performing in situ hybridization, we demonstrated the wide expression of scarb1, abca1a, abca1b, abcg1, and cd36 in the brain of adult zebrafish. Scarb1 gene expression was detected in neural stem cells (NSCs), suggesting a possible role of HDLs in NSC activity. Accordingly, intracerebroventricular injection of HDLs leads to their uptake by NSCs without modulating their proliferation. Next, we studied the biodistribution of HDLs in the zebrafish body. In homeostatic conditions, intraperitoneal injection of HDLs led to their accumulation in the liver, kidneys, and cerebral endothelial cells in zebrafish, similar to that observed in mice. After telencephalic injury, HDLs were diffused within the damaged parenchyma and were taken up by ventricular cells, including NSCs. However, they failed to modulate the recruitment of microglia cells at the injury site and the injury-induced proliferation of NSCs. In conclusion, our results clearly show a functional HDL uptake process involving several receptors that may impact brain homeostasis and suggest the use of HDLs as delivery vectors to target NSCs for drug delivery to boost their neurogenic activity.

Sphingosine-1-phosphate as a key player of insulin secretion induced by high-density lipoprotein treatment.

Beta cell failure is one of the most important features of type 2 diabetes mellitus (T2DM). High-density lipoprotein (HDL) has been proposed to improve ß-cell function. However, the mechanisms involved in this process are still poorly understood. The aim of this study was to investigate the contribution of sphingosine-1-phosphate (S1P) in the impact of HDL treatment on insulin secretion by pancreatic ß-cells and to determine its mechanisms. Primary cultures of ß-cells isolated from rat were treated with or without HDL in the presence or absence of S1P pathway inhibitors and insulin secretion response was analyzed. The S1P content of HDL (HDL-S1P) isolated from T2DM patients was analyzed and correlated to the HDL-induced insulin secretion. The expression of genes involved in the biosynthesis of the insulin was also evaluated. HDL as well as S1P treatment enhanced glucose-stimulated insulin secretion (GSIS). In HDL isolated from T2DM patients, while HDL-S1P was strongly correlated to its pro-secretory capacity (r = 0.633, p = 0.005), HDL-cholesterol and apolipoprotein AI levels were not. HDL-induced GSIS was blocked by the S1P1/3 antagonist but not by the S1P2 antagonist, and was also accompanied by increased intracellular S1P in ß-cells. We also observed that HDL improved GSIS without significant changes in expression levels of insulin biosynthesis genes. Our present study highlights the importance HDL-S1P in GSIS in T2DM patients and demonstrates that HDL induces insulin secretion by a process involving both intra- and extra-cellular sources of S1P independently of an effect on insulin biosynthesis genes.

Rationale and design of ApoA-I Event Reducing in Ischemic Syndromes II (AEGIS-II): A phase 3, multicenter, double-blind, randomized, placebo-controlled, parallel-group study to investigate the efficacy and safety of CSL112 in subjects after acute myocardial infarction.

Acute myocardial infarction (MI) patients remain at high risk for recurrent events. Cholesterol efflux, mediated by apolipoprotein A-I, removes excess cholesterol from atherosclerotic plaque and transports it to the liver for excretion. Impaired cholesterol efflux is associated with higher cardiovascular (CV) event rates among both patients with stable coronary artery disease and recent MI. CSL112, a novel intravenous formulation of apolipoprotein A-I (human) derived from human plasma, increases cholesterol efflux capacity. AEGIS-II is a phase 3, multicenter, double-blind, randomized, placebo-controlled, parallel-group trial investigating the efficacy and safety of CSL112 compared to placebo among high-risk acute MI participants. Eligibility criteria include age ≥ 18 years with type 1 (spontaneous) MI, evidence of multivessel stable coronary artery disease, and presence of diabetes requiring pharmacotherapy, or ≥2 of the following: age ≥ 65 years, prior MI, or peripheral artery disease. A target sample of 17,400 participants will be randomized 1:1 to receive 4 weekly infusions of CSL112 6 g or placebo, initiated prior to or on the day of discharge and within 5 days of first medical contact. The primary outcome is the time to first occurrence of the composite of CV death, MI, or stroke through 90 days. Key secondary outcomes include the total number of hospitalizations for coronary, cerebral, or peripheral ischemia through 90 days and time to first occurrence of the composite primary outcome through 180 and 365 days. AEGIS-II will be the first trial to formally test whether enhancing cholesterol efflux can reduce the rate of recurrent major adverse CV events.

Low-Density Lipoproteins, High-Density Lipoproteins (HDL), and HDL-Associated Proteins Differentially Modulate Chronic Myelogenous Leukemia Cell Viability.

Cellular lipid metabolism, lipoprotein interactions, and liver X receptor (LXR) activation have been implicated in the pathophysiology and treatment of cancer, although findings vary across cancer models and by lipoprotein profiles. In this study, we investigated the effects of human-derived low-density lipoproteins (LDL), high-density lipoproteins (HDL), and HDL-associated proteins apolipoprotein A1 (apoA1) and serum amyloid A (SAA) on markers of viability, cholesterol flux, and differentiation in K562 cells-a bone marrow-derived, stem-like erythroleukemia cell model of chronic myelogenous leukemia (CML). We further evaluated whether lipoprotein-mediated effects were altered by concomitant LXR activation. We observed that LDL promoted higher K562 cell viability in a dose- and time-dependent manner and increased cellular cholesterol concentrations, while LXR activation by the agonist TO901317 ablated these effects. LXR activation in the presence of HDL, apoA1 and SAA-rich HDL suppressed K562 cell viability, while robustly inducing mRNA expression of ATP-binding cassette transporter A1 (ABCA1). HDL and its associated proteins additionally suppressed mRNA expression of anti-apoptotic B-cell lymphoma-extra large (BCL-xL), and the erythroid lineage marker 5'-aminolevulinate synthase 2 (ALAS2), while SAA-rich HDL induced mRNA expression of the megakaryocytic lineage marker integrin subunit alpha 2b (ITGA2B). Together, these findings suggest that lipoproteins and LXR may impact the viability and characteristics of CML cells.

Sterically stabilized recombined HDL composed of modified apolipoprotein A-I for efficient targeting toward glioma cells.

Reconstituted high density lipoprotein (rHDL) has been regarded as a promising brain-targeting vehicle for anti-glioma drugs under the mediation of apolipoprotein A-I (apoA-I). However, some stability issues relating to drug leakage and consequent reduced targeting efficiency in the course of discoidal rHDL (d-rHDL) circulating in blood hinder its broad application. The objective of the study was to develop a novel stabilized d-rHDL by replacing cholesterol and apoA-I with mono-cholesterol glutarate (MCG) modified apoA-I (termed as mA) and to evaluate its allosteric behavior and glioma targeting. MCG was synthesized through esterifying the hydroxyl of cholesterol with glutaric anhydride and characterized by FI-IR and 1H NMR. d-rHDL assembled with mA (termed as m-d-rHDL) presented similar properties such as minute particle size and disk-like appearance resembling nascent HDL. Morphological transformation observation and in vitro release plots convinced that the modification of cholesterol could effectively inhibit the remolding of d-rHDL. The uptake of m-d-rHDL by LCAT-pretreated bEND.3 cells was significantly higher than that of d-rHDL, thereby serving as another proof for the capability of m-d-rHDL in enhancing targeting property. Besides, apoA-I anchoring into m-d-rHDL played a critical role in the endocytosis process into bEND.3 cells and C6 cells, which implied the possibility of traversing blood brain barrier and accumulating in the brain and glioma. These results suggested that the modification toward cholesterol to improve the stability of d-rHDL is advantageous, and that this obtained m-d-rHDL revealed great potential for realization of suppressing the remolding of d-rHDL in the brain-targeted treatment of glioma for drug delivery.

Reconstituted High-density Lipoprotein Therapy Improves Survival in Mouse Models of Sepsis.

BACKGROUND: High-density lipoproteins exert pleiotropic effects including antiinflammatory, antiapoptotic, and lipopolysaccharide-neutralizing properties. The authors assessed the effects of reconstituted high-density lipoproteins (CSL-111) intravenous injection in different models of sepsis. METHODS: Ten-week-old C57BL/6 mice were subjected to sepsis by cecal ligation and puncture or intraperitoneal injection of Escherichia coli or Pseudomonas aeruginosa pneumonia. CSL-111 or saline solution was administrated 2 h after the sepsis. Primary outcome was survival. Secondary outcomes were plasma cell-free DNA and cytokine concentrations, histology, bacterial count, and biodistribution. RESULTS: Compared with saline, CSL-111 improved survival in cecal ligation and puncture and intraperitoneal models (13 of 16 [81%] survival rate vs. 6 of 16 [38%] in the cecal ligation and puncture model; P = 0.011; 4 of 10 [40%] vs. 0 of 10 [0%] in the intraperitoneal model; P = 0.011). Cell-free DNA concentration was lower in CSL-111 relative to saline groups (68 [24 to 123] pg/ml vs. 351 [333 to 683] pg/ml; P < 0.001). Mice injected with CSL-111 presented a decreased bacterial count at 24 h after the cecal ligation and puncture model both in plasma (200 [28 to 2,302] vs. 2,500 [953 to 3,636] colony-forming unit/ml; P = 0.021) and in the liver (1,359 [360 to 1,648] vs. 1,808 [1,464 to 2,720] colony-forming unit/ml; P = 0.031). In the pneumonia model, fewer bacteria accumulated in liver and lung of the CSL-111 group. CSL-111-injected mice had also less lung inflammation versus saline mice (CD68+ to total cells ratio: saline, 0.24 [0.22 to 0.27]; CSL-111, 0.07 [0.01 to 0.09]; P < 0.01). In all models, no difference was found for cytokine concentration. Indium bacterial labeling underlined a potential hepatic bacterial clearance possibly promoted by high-density lipoprotein uptake. CONCLUSIONS: CSL-111 infusion improved survival in different experimental mouse models of sepsis. It reduced inflammation in both plasma and organs and decreased bacterial count. These results emphasized the key role for high-density lipoproteins in endothelial and organ protection, but also in lipopolysaccharide/bacteria clearance. This suggests an opportunity to explore the therapeutic potential of high-density lipoproteins in septic conditions.

Phospholipid Component Defines Pharmacokinetic and Pharmacodynamic Properties of Synthetic High-Density Lipoproteins.

Synthetic high-density lipoprotein (sHDL) nanoparticles composed of apolipoprotein A-I mimetic peptide and phospholipids have been shown to reduce atherosclerosis in animal models. Cholesterol is mobilized from atheroma macrophages by sHDL into the blood compartment and delivered to the liver for elimination. Historically, sHDL drug discovery efforts were focused on optimizing peptide sequences for interaction with cholesterol cellular transporters rather than understanding how both sHDL components, peptide and lipid, influence its pharmacokinetic and pharmacodynamic profiles. We designed two sets of sHDL having either identical phospholipid but variable peptide sequences with different plasma stability or identical peptide and phospholipids with variable fatty acid chain length and saturation. We found that sHDL prepared with proteolytically stable 22A-P peptide had 2-fold longer circulation half-time relative to the less stable 22A peptide. Yet, longer half-life did not translate into any improvement in cholesterol mobilization. In contrast, sHDL with variable phospholipid compositions showed significant differences in phospholipid PK, with distearoyl phosphatidylcholine-based sHDL demonstrating the longest half-life of 6.0 hours relative to 1.0 hour for palmitoyl-oleoyl phosphatidylcholine-based sHDL. This increase in half-life corresponded to an approx. 6.5-fold increase in the area under the curve for the mobilized cholesterol. Therefore, the phospholipid component in sHDL plays a major role in cholesterol mobilization in vivo and should not be overlooked in the design of future sHDL. SIGNIFICANCE STATEMENT: The phospholipid composition in sHDL plays a critical role in determining half-life and cholesterol mobilization in vivo.

Infusions of Large Synthetic HDL Containing Trimeric apoA-I Stabilize Atherosclerotic Plaques in Hypercholesterolemic Rabbits.

BACKGROUND: Among strategies to reduce the remaining risk of cardiovascular disease, interest has focused on using infusions of synthetic high-density lipoprotein (sHDL). METHODS: New Zealand rabbits underwent a perivascular injury at both carotids and were randomly allocated into 2 protocols: (1) a single-dose study, where rabbits were treated with a single infusion of sHDL containing a trimeric form of human apoA-I (TN-sHDL, 200 mg/kg) or with Placebo; (2) a multiple-dose study, where 4 groups of rabbits were treated 5 times with Placebo or TN-sHDL at different doses (8, 40, 100 mg/kg). Plaque changes were analysed in vivo by intravascular ultrasound. Blood was drawn from rabbits for biochemical analyses and cholesterol efflux capacity evaluation. RESULTS: In both protocols, atheroma volume in the Placebo groups increased between the first and the second intravascular ultrasound evaluation. A stabilization or a slight regression was instead observed vs baseline in the TN-sHDL-treated groups (P < 0.005 vs Placebo after infusion). TN-sHDL treatment caused a sharp rise of plasma-free cholesterol levels and a significant increase of total cholesterol efflux capacity. Histologic analysis of carotid plaques showed a reduced macrophage accumulation in TN-sHDL-treated rabbits compared with Placebo (P < 0.05). CONCLUSIONS: Our results demonstrate that acute and subacute treatments with TN-sHDL are effective in stabilizing atherosclerotic plaques in a rabbit model. This effect appears to be related to a reduced intraplaque accumulation of inflammatory cells. Besides recent failures in proving its efficacy, sHDL treatment remains a fascinating therapeutic option for the reduction of cardiovascular risk.

Peripheral administration of human recombinant ApoJ/clusterin modulates brain beta-amyloid levels in APP23 mice.

BACKGROUND: ApoJ/clusterin is a multifunctional protein highly expressed in the brain. The implication of ApoJ in ß-amyloid (Aß) fibrillization and clearance in the context of Alzheimer's disease has been widely studied, although the source and concentration of ApoJ that promotes or inhibits Aß cerebral accumulation is not clear yet. ApoJ is abundant in plasma and approximately 20% can appear bound to HDL-particles. In this regard, the impact of plasmatic ApoJ and its lipidation status on cerebral ß-amyloidosis is still not known. Hence, our main objective was to study the effect of a peripheral increase of free ApoJ or reconstituted HDL particles containing ApoJ in an experimental model of cerebral ß-amyloidosis. METHODS: Fourteen-month-old APP23 transgenic mice were subjected to subchronic intravenous treatment with rHDL-rApoJ nanodiscs or free rApoJ for 1 month. Aß concentration and distribution in the brain, as well as Aß levels in plasma and CSF, were determined after treatments. Other features associated to AD pathology, such as neuronal loss and neuroinflammation, were also evaluated. RESULTS: Both ApoJ-based treatments prevented the Aß accumulation in cerebral arteries and induced a decrease in total brain insoluble Aß42 levels. The peripheral treatment with rApoJ also induced an increase in the Aß40 levels in CSF, whereas the concentration remained unaltered in plasma. At all the endpoints studied, the lipidation of rApoJ did not enhance the protective properties of free rApoJ. The effects obtained after subchronic treatment with free rApoJ were accompanied by a reduction in hippocampal neuronal loss and an enhancement of the expression of a phagocytic marker in microglial cells surrounding Aß deposits. Finally, despite the activation of this phagocytic phenotype, treatments did not induce a global neuroinflammatory status. In fact, free rApoJ treatment was able to reduce the levels of interleukin-17 (IL17) and keratinocyte chemoattractant (KC) chemokine in the brain. CONCLUSIONS: Our results demonstrate that an increase in circulating human rApoJ induces a reduction of insoluble Aß and CAA load in the brain of APP23 mice. Thus, our study suggests that peripheral interventions, based on treatments with multifunctional physiological chaperones, offer therapeutic opportunities to regulate the cerebral Aß load.

Rational Design of Lovastatin-Loaded Spherical Reconstituted High Density Lipoprotein for Efficient and Safe Anti-Atherosclerotic Therapy.

Reconstituted high density lipoprotein (rHDL) is a biomimetic nanoparticle with plaque targeting and anti-atherosclerotic efficacy. In this work, we report on a strategy to rational design of lovastatin (LOV)-loaded spherical rHDL (LOV-s-rHDL) for efficient and safe anti-atherosclerotic therapy. Briefly, three LOV-s-rHDLs were formulated with LOV/s-rHDL at ratios of 8:1, 10:1, and 15:1 upon their respective median-effect values ( Dm). The combined inhibitory effect between LOV and s-rHDL of different LOV-s-rHDL formulations on DiI-labeled oxLDL internalization was systemically investigated in RAW 264.7 cells based on the median-effect principle. Median-effect analysis demonstrated that the optimized LOV-s-rHDL was formulated with a ratio of 10:1 ( Dm LOV: Dm s-rHDL), in which LOV and s-rHDL carrier showed the best synergistic effect, presumably ascribed to their inhibitory effect on CD36 and SR-A expression according to the Western blot analysis. In vivo pharmacodynamics studies showed that the optimized LOV-s-rHDL displayed the most pronounced anti-atherosclerotic effect on decreasing plaque area and reducing the MMP level following an 8-week dosing regimen. In vivo atherosclerotic plaque targeting analysis revealed that s-rHDL had potent plaque targeting efficacy, probably owing to the interaction between apoA-I and scavenger receptor B-I. Furthermore, we observed that the optimized LOV-s-rHDL exhibited a favorable safety profile as evidenced by the results of a hemolysis assay, cell cytotoxicity study, and in vivo safety test. Collectively, the rational design of the biomimetic LOV-s-rHDL based on the median-effect analysis provides an efficient strategy to achieve a synergistic and safe anti-atherosclerotic therapy.

Reassembly of native components with donepezil to execute dual-missions in Alzheimer's disease therapy.

Alzheimer's disease (AD) is a multifaceted and progressive neurodegenerative disease characterized by accumulation of amyloid-beta (Aß) and deficits of acetylcholine. Accordingly, the intra-/extra-cerebral level of high density lipoprotein (HDL) is crucial on the pathogenesis of AD; and most of all, various HDL-protein subtypes play a double-edged role in AD pathology, of which apolipoprotein A-I (apoA-I) gives protective outcomes. Inspired from "HDL bionics", we proposed biologically reassembled nanodrugs, donepezil-loaded apolipoprotein A-I-reconstituted HDL (rHDL/Do) that concurrently executed dual-missions of Aß-targeting clearance and acetylcholinesterase (AChE) inhibition in AD therapy. Once prepared, rHDL/Do nanodrug achieved high drug encapsulation efficiency of 90.47%, and mimicked the configurations and properties of natural lipoproteins aiming to significantly enhance BBB penetration and modulate Aß-induced neuronal damage both in vitro and in vivo. Surface plasmon resonance (SPR) analysis confirmed that rHDL/Do facilitated microglial-mediated Aß intake and degradation, demonstrating low KD value with Aß affinity (2.45 × 10-8 of Aß monomer and 2.78 × 10-8 of Aß oligomer). In AD animal models, daily treatment of rHDL/Do efficiently inhibited AChE activity, ameliorated neurologic variation, promoted Aß clearance, and rescued memory loss at a safe level. The collective findings indicated that the biological nanodrug was provided with the capacities of BBB penetration, Aß capture and degradation via microglial cells, and cholinergic dysfunction amelioration after controlled donepezil release. In summary, rHDL/Do nanodrugs could offer a promising strategy to synergize both symptom control and disease modification in AD therapy.

Moderate Renal Impairment Does Not Impact the Ability of CSL112 (Apolipoprotein A-I [Human]) to Enhance Cholesterol Efflux Capacity.

CSL112 (apolipoprotein A-I [human]) is a novel intravenous formulation of plasma-derived apolipoprotein A-I (apoA-I) that enhances cholesterol efflux capacity. Renal impairment is a common comorbidity in acute myocardial infarction patients and is associated with impaired lipid metabolism. The aim of this phase 1 study was to assess the impact of moderate renal impairment on the pharmacokinetic and pharmacodynamic profile of CSL112. Sixteen subjects with moderate renal impairment and 16 age-, sex-, and weight-matched subjects with normal renal function participated in the study. Within each renal function cohort, subjects were randomized 3:1 to receive a single intravenous infusion of CSL112 2 g (n = 6) or placebo (n = 2) or CSL112 6 g (n = 6) or placebo (n = 2). At baseline, subjects with moderate renal impairment versus normal renal function had higher total cholesterol efflux, ABCA1-dependent cholesterol efflux capacity, and pre-ß1-high-density lipoprotein (HDL) levels. Infusing CSL112 resulted in similar, immediate, robust, dose-dependent elevations in apoA-I and cholesterol efflux capacity in both renal function cohorts and significantly greater elevations in pre-ß1-HDL (P < .05) in moderate renal impairment. Lecithin-cholesterol acyltransferase activity, demonstrated by a time-dependent change in the ratio of unesterified to esterified cholesterol, did not differ by renal function. No meaningful changes in proatherogenic lipid levels were observed. Moderate renal impairment did not impact the ability of CSL112 to enhance cholesterol efflux capacity. CSL112 may represent a novel therapy to reduce the risk of early recurrent cardiovascular events following acute myocardial infarction in patients with or without moderate renal impairment.

The CSL112-2001 trial: Safety and tolerability of multiple doses of CSL112 (apolipoprotein A-I [human]), an intravenous formulation of plasma-derived apolipoprotein A-I, among subjects with moderate renal impairment after acute myocardial infarction.

BACKGROUND: CSL112 (apolipoprotein A-I [human]) is a plasma-derived apolipoprotein A-I developed for early reduction of cardiovascular risk following an acute myocardial infarction (AMI). The safety of CSL112 among AMI subjects with moderate, stage 3 chronic kidney disease (CKD) is unknown. METHODS: CSL112_2001, a multicenter, placebo-controlled, parallel-group, double-blind, randomized phase 2 trial, enrolled patients with moderate CKD within 7 days following AMI. Enrollment was stratified on the basis of estimated glomerular filtration rate and presence of diabetes requiring treatment. Patients were randomized in a 2:1 ratio to receive 4 weekly infusions of CSL112 6 g or placebo. The co-primary safety end points were renal serious adverse events (SAEs) and acute kidney injury, defined as an increase ≥26.5 µmol/L in baseline serum creatinine for more than 24 hours, during the treatment period. RESULTS: A total of 83 patients were randomized (55 CSL112 vs 28 placebo). No increase in renal SAEs was observed in the CSL112 group compared with placebo (CSL112 = 1 [1.9%], placebo = 4 [14.3%]). Similarly, no increase in acute kidney injury events was observed (CSL112 = 2 [4.0%], placebo = 4 [14.3%]). Rates of other SAEs were similar between groups. CSL112 administration resulted in increases in ApoA-I and cholesterol efflux similar to those observed in patients with AMI and normal renal function or stage 2 CKD enrolled in the ApoA-I Event Reducing in Ischemic Syndromes I trial. CONCLUSIONS: These results demonstrate the acceptable safety of the 6-g dose of CSL112 among AMI subjects with moderate stage 3 CKD and support inclusion of these patients in a phase 3 cardiovascular outcomes trial powered to assess efficacy.

[99mTc-HYNIC-N-dodecylamide]: a new hydrophobic tracer for labelling reconstituted high-density lipoproteins (rHDL) for radioimaging.

Despite the widespread use of nanotechnology in radio-imaging applications, lipoprotein based delivery systems have received only limited attention so far. These studies involve the synthesis of a novel hydrophobic radio-imaging tracer consisting of a hydrazinonicotinic acid (HYNIC)-N-dodecylamide and 99mTc conjugate that can be encapsulated into rHDL nanoparticles (NPs). These rHDL NPs can selectively target the Scavenger Receptor type B1 (SR-B1) that is overexpressed on most cancer cells due to excess demand for cholesterol for membrane biogenesis and thus can target tumors in vivo. We provide details of the tracer synthesis, characterization of the rHDL/tracer complex, in vitro uptake, stability studies and in vivo application of this new radio-imaging approach.