Fish Oil Supplementation Modifies the Proteome, Lipidome, and Function of High-Density Lipoprotein: Findings from a Trial in Young Healthy Adults.

BACKGROUND: Fish oil with the ω-3 fatty acids EPA and DHA is an FDA-approved treatment of patients with severe hypertriglyceridemia. Furthermore, EPA is an FDA-approved treatment of patients with high risk of cardiovascular disease (CVD); however, the cardioprotective mechanisms are unclear. OBJECTIVES: We aimed to determine if fish oil supplementation is cardioprotective due to beneficial modifications in HDL particles. METHODS: Seven fish oil naïve subjects without a history of CVD were recruited to take a regimen of fish oil (1125 mg EPA and 875 mg DHA daily) for 30 d, followed by a 30-d washout period wherein no fish oil supplements were taken. HDL isolated from fasting whole blood at each time point via 2-step ultracentrifugation (ucHDL) was assessed for proteome, lipidome, cholesterol efflux capacity (CEC), and anti-inflammatory capacity. RESULTS: Following fish oil supplementation, the HDL-associated proteins immunoglobulin heavy constant γ1, immunoglobulin heavy constant α1, apolipoprotein D, and phospholipid transfer protein decreased compared to baseline (P < 0.05). The HDL-associated phospholipid families sphingomyelins, phosphatidylcholines, and phosphatidylserines increased after fish oil supplementation relative to baseline (P < 0.05). Compared to baseline, fish oil supplementation increased serum HDL's CEC (P = 0.002). Fish oil-induced changes (Post compared with Baseline) in serum HDL's CEC positively correlated with plasma EPA levels (R2 = 0.7256; P = 0.015). Similarly, fish oil-induced changes in ucHDL's CEC positively correlated with ucHDL's ability to reduce interleukin 10 (R2 = 0.7353; P = 0.014) and interleukin 6 mRNA expression (R2 = 0.6322; P =0.033) in a human macrophage cell line. CONCLUSIONS: Overall, fish oil supplementation improved HDL's sterol efflux capacity through comprehensive modifications to its proteome and lipidome.

Divergent low-density lipoprotein receptor (LDLR) linked to low VSV G-dependent viral infectivity and unique serum lipid profile in zebra finches.

The low-density lipoprotein receptor (LDLR) is key to cellular cholesterol uptake and is also the main receptor for the vesicular stomatitis virus glycoprotein (VSV G). Here we show that in songbirds LDLR is highly divergent and lacks domains critical for ligand binding and cellular trafficking, inconsistent with universal structure conservation and function across vertebrates. Linked to the LDLR functional domain loss, zebra finches show inefficient infectivity by lentiviruses (LVs) pseudotyped with VSV G, which can be rescued by the expression of human LDLR. Finches also show an atypical plasma lipid distribution that relies largely on high-density lipoprotein (HDL). These findings provide insights into the genetics and evolution of viral infectivity and cholesterol transport mechanisms in vertebrates.

Macrophage LRP1 (Low-Density Lipoprotein Receptor-Related Protein 1) Is Required for the Effect of CD47 Blockade on Efferocytosis and Atherogenesis-Brief Report.

OBJECTIVE: Antibody blockade of the "do not eat me" signal CD47 (cluster of differentiation 47) enhances efferocytosis and reduces lesion size and necrotic core formation in murine atherosclerosis. TNF (Tumor necrosis factor)-α expression directly enhances CD47 expression, and elevated TNF-α is observed in the absence of the proefferocytosis receptor LRP1 (low-density lipoprotein receptor-related protein 1), a regulator of atherogenesis and inflammation. Thus, we tested the hypothesis that CD47 blockade requires the presence of macrophage LRP1 to enhance efferocytosis, temper TNF-α-dependent inflammation, and limit atherosclerosis. Approach and Results: Mice lacking systemic apoE (apoE-/-), alone or in combination with the loss of macrophage LRP1 (double knockout), were fed a Western-type diet for 12 weeks while receiving anti-CD47 antibody (anti-CD47) or IgG every other day. In apoE-/- mice, treatment with anti-CD47 reduced lesion size by 25.4%, decreased necrotic core area by 34.5%, and decreased the ratio of free:macrophage-associated apoptotic bodies by 47.6% compared with IgG controls (P<0.05), confirming previous reports. Double knockout mice treated with anti-CD47 showed no differences in lesion size, necrotic core area, or the ratio of free:macrophage-associated apoptotic bodies compared with IgG controls. In vitro efferocytosis was 30% higher when apoE-/- phagocytes were incubated with anti-CD47 compared with IgG controls (P<0.05); however, anti-CD47 had no effect on efferocytosis in double knockout phagocytes. Analyses of mRNA and protein showed increased CD47 expression in anti-inflammatory IL (interleukin)-4 treated LRP1-/- macrophages compared with wild type, but no differences were observed in inflammatory lipopolysaccharide-treated macrophages. CONCLUSIONS: The proefferocytosis receptor LRP1 in macrophages is necessary for anti-CD47 blockade to enhance efferocytosis, limit atherogenesis, and decrease necrotic core formation in the apoE-/- model of atherosclerosis.

Vitamin D and docosahexaenoic acid inhibit proliferation of the ovarian cancer cell line OVCAR4.

BACKGROUND: Ovarian cancer is one of the deadliest cancers in women. Improved preventative, diagnostic, and therapeutic strategies are needed. Certain dietary patterns and nutrients such as vitamin D and omega-3 fatty acids are associated with reduced cancer risk, but their effects on ovarian cancer remain to be fully elucidated, and their combined effects have not been explored. AIM: To determine the individual and combined effects of the active vitamin D metabolite, calcitriol, and the omega-3 fatty acid, docosahexaenoic acid, on cell growth, and the abundance of the vitamin D receptor (VDR), proteins that modulate cell cycle progression, and apoptotic markers. METHODS: OVCAR4 cells, a model of ovarian cancer, were treated with calcitriol, and docosahexaenoic acid, either alone or in combination. Effects on cell growth were determined by the sulforhodamine B assay. Changes in VDR, the cell cycle promotor c-Myc, the cell cycle inhibitor p27 and cleaved PARP, were determined by Western blotting. RESULTS: While OVCAR4 cell growth was inhibited by individual treatment with either calcitriol or docosahexaenoic acid, the combined treatment revealed enhanced growth inhibition as compared to either treatment alone. Furthermore, long-term treatment (12 days) yielded stronger growth inhibition at lower concentrations as compared to short-term treatments (3 days). Accompanying this growth inhibition was a decrease in c-Myc, and an increase in p27. CONCLUSIONS: The observed reduction in cell growth mediated by calcitriol and docosahexaenoic acid highlights the need for further research utilizing these nutrients, alone and especially in combination, to support ovarian cancer prevention and treatment.

Insights into the kinetics and dynamics of the furin-cleaved form of PCSK9.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) regulates cholesterol metabolism by inducing the degradation of hepatic low density lipoprotein receptors (LDLRs). Plasma PCSK9 has 2 main molecular forms: a 62 kDa mature form (PCSK9_62) and a 55 kDa, furin-cleaved form (PCSK9_55). PCSK9_55 is considered less active than PCSK9_62 in degrading LDLRs. We aimed to identify the site of PCSK9_55 formation (intracellular vs. extracellular) and to further characterize the LDLR-degradative function of PCSK9_55 relative to PCSK9_62. Coexpressing PCSK9_62 with furin in cell culture induced formation of PCSK9_55, most of which was found in the extracellular space. Under the same conditions, we found that i) adding a cell-permeable furin inhibitor preferentially decreased the formation of PCSK9_55 extracellularly; ii) using pulse-chase analysis, we observed the formation of PCSK9_55 exclusively extracellularly in a time-dependent manner. A recombinant form of PCSK9_55 was efficiently produced but displayed impaired secretion that resulted in its intracellular trapping. However, the nonsecreted PCSK9_55 was able to induce degradation of LDLR, though with 50% lower efficiency than PCSK9_62. Collectively, our data show that 1) PCSK9_55 is formed extracellularly; 2) PCSK9_55 has a shorter half-life; 3) there is a small intracellular pool of PCSK9_55 that is not secreted; and 4) PCSK9_55 retained within the cell maintains a reduced efficiency to cause LDLR degradation.

Coronary Artery Disease Risk-Associated Plpp3 Gene and Its Product Lipid Phosphate Phosphatase 3 Regulate Experimental Atherosclerosis.

OBJECTIVE: Genome-wide association studies identified novel loci in PLPP3(phospholipid phosphatase 3) that associate with coronary artery disease risk independently of traditional risk factors. PLPP3 encodes LPP3 (lipid phosphate phosphatase 3), a cell-surface enzyme that can regulate the availability of bioactive lysophopsholipids including lysophosphatidic acid (LPA). The protective allele of PLPP3 increases LPP3 expression during cell exposure to oxidized lipids, however, the role of LPP3 in atherosclerosis remains unclear. Approach and Results: In this study, we sought to validate LPP3 as a determinate of the development of atherosclerosis. In experimental models of atherosclerosis, LPP3 is upregulated and co-localizes with endothelial, smooth muscle cell, and CD68-positive cell markers. Global post-natal reductions in Plpp3 expression in mice substantially increase atherosclerosis, plaque-associated LPA, and inflammation. Although LPP3 expression increases during ox-LDL (oxidized low-density lipoprotein)-induced phenotypic modulation of bone marrow-derived macrophages, myeloid Plpp3 does not appear to regulate lesion formation. Rather, smooth muscle cell LPP3 expression is a critical regulator of atherosclerosis and LPA content in lesions. Moreover, mice with inherited deficiency in LPA receptor signaling are protected from experimental atherosclerosis. CONCLUSIONS: Our results identify a novel lipid signaling pathway that regulates inflammation in the context of atherosclerosis and is not related to traditional risk factors. Pharmacological targeting of bioactive LPP3 substrates, including LPA, may offer an orthogonal approach to lipid-lowering drugs for mitigation of coronary artery disease risk.

US medical and surgical society position statements on physician-assisted suicide and euthanasia: a review.

BACKGROUND: An analysis of the position statements of secular US medical and surgical professional societies on physician-assisted suicide (PAS) and euthanasia have not been published recently. Available statements were evaluated for position, content, and sentiment. METHODS: In order to create a comprehensive list of secular medical and surgical societies, the results of a systematic search using Google were cross-referenced with a list of societies that have a seat on the American Medical Association House of Delegates. Societies with position statements were identified. These statements were divided into 5 categories: opposed to PAS and/or euthanasia, studied neutrality, supportive, acknowledgement without statement, and no statement. Linguistic analysis was performed using RapidMinder in order to determine word frequency and sentiment respective to individual statements. To ensure accuracy, only statements with word counts > 100 were analyzed. A 2-tailed independent t test was used to test for variance among sentiment scores of opposing and studied neutrality statements. RESULTS: Of 150 societies, only 12 (8%) have position statements on PAS and euthanasia: 11 for PAS (5 opposing and 4 studied neutrality) and 9 for euthanasia (6 opposing and 2 studied neutrality). Although the most popular words used in opposing and studied neutrality statements are similar, notable exceptions exist (suicide, medicine, and treatment appear frequently in opposing statements, but not in studied neutrality statements, whereas psychologists, law, and individuals appear frequently in studied neutrality statements, but not in opposing statements). Sentiment scores for opposing and studied neutrality statements do not differ (mean, 0.094 vs. 0.104; P = 0.90). CONCLUSIONS: Few US medical and surgical societies have position statements on PAS and euthanasia. Among them, opposing and studied neutrality statements share similar linguistic sentiment. Opposing and studied neutrality statements have clear differences, but share recommendations. Both opposing and studied neutrality statements cite potential risks of PAS legalization and suggest that good palliative care might diminish a patient's desire for PAS.

Deletion of Macrophage Low-Density Lipoprotein Receptor-Related Protein 1 (LRP1) Accelerates Atherosclerosis Regression and Increases C-C Chemokine Receptor Type 7 (CCR7) Expression in Plaque Macrophages.

BACKGROUND: We previously showed that mice lacking MΦLRP1-/- (low-density lipoprotein receptor-related protein 1 in macrophages) undergo accelerated atherosclerotic plaque formation due to changes in macrophages including increased apoptosis, decreased efferocytosis, and exaggerated transition to the inflammatory M1 phenotype. Here we sought to explore the role of macrophage low-density lipoprotein receptor-related protein 1 during regression of atherosclerosis since regressing plaques are characterized by transitioning of macrophages to M2 status as inflammation resolves. METHODS: Apolipoprotein E-/- mice on a high-fat diet for 12 weeks were reconstituted with bone marrow from apolipoprotein E-producing wild-type or MΦLRP1-/- mice, and then placed on a chow diet for 10 weeks (n=9 to 11 mice/group). A cohort of apolipoprotein E-/- mice reconstituted with apolipoprotein E-/- bone marrow served as baseline controls (n=9). RESULTS: Plaques of both wild-type and MΦLRP1-/- bone marrow recipients regressed compared with controls (11% and 22%, respectively; P<0.05), and plaques of MΦLRP1-/- recipients were 13% smaller than those of wild-type recipients ( P<0.05). Recipients of MΦLRP1-/- marrow had 36% fewer M1 macrophages ( P<0.01) and 2.5-fold more CCR7 (C-C chemokine receptor type 7)-positive macrophages in the plaque relative to wild-type mice ( P<0.01). Additionally, in vivo studies of cellular egress showed a 4.6-fold increase in 5-ethynyl-2´-deoxyuridine-labeled CCR7+ macrophages in mediastinal lymph nodes. Finally, in vivo studies of reverse cholesterol transport showed a 1.4-fold higher reverse cholesterol transport in MΦLRP1-/- recipient mice ( P<0.01). CONCLUSIONS: Absence of macrophage low-density lipoprotein receptor-related protein 1 unexpectedly accelerates atherosclerosis regression, enhances reverse cholesterol transport, and increases expression of the motility receptor CCR7, which drives macrophage egress from lesions.

Ethics and the Legalization of Physician-Assisted Suicide: An American College of Physicians Position Paper.

Calls to legalize physician-assisted suicide have increased and public interest in the subject has grown in recent years despite ethical prohibitions. Many people have concerns about how they will die and the emphasis by medicine and society on intervention and cure has sometimes come at the expense of good end-of-life care. Some have advocated strongly, on the basis of autonomy, that physician-assisted suicide should be a legal option at the end of life. As a proponent of patient-centered care, the American College of Physicians (ACP) is attentive to all voices, including those who speak of the desire to control when and how life will end. However, the ACP believes that the ethical arguments against legalizing physician-assisted suicide remain the most compelling. On the basis of substantive ethics, clinical practice, policy, and other concerns articulated in this position paper, the ACP does not support legalization of physician-assisted suicide. It is problematic given the nature of the patient-physician relationship, affects trust in the relationship and in the profession, and fundamentally alters the medical profession's role in society. Furthermore, the principles at stake in this debate also underlie medicine's responsibilities regarding other issues and the physician's duties to provide care based on clinical judgment, evidence, and ethics. Society's focus at the end of life should be on efforts to address suffering and the needs of patients and families, including improving access to effective hospice and palliative care. The ACP remains committed to improving care for patients throughout and at the end of life.

Crucial conversations about weight management with healthcare providers: patients' perspectives and experiences.

PURPOSE: To elicit patient experiences of weight management discussions with providers and provide recommendations for future weight-related discussions. METHODS: 1000 patients who recently saw their provider for non-weight specific appointments were mailed measures of demographics, self-reported height and weight, activity level, adherence, perceptions of and recommendations for weight-related discussions, and internalized weight bias. This study was primarily descriptive and utilized a mixed method design including collection of quantitative and qualitative data. RESULTS: 242 patients responded (24 % response rate); 32.4 % overweight (N = 72), 41.9 % obese (N = 93). 47 % of overweight and 71 % of obese patients recalled that their provider discussed weight; 92 % were motivated to follow recommendations and 89 % felt confident doing so. Most patients (75 %) would like their provider to be "very direct/straightforward" when discussing weight, and 52 % would be "not at all offended" if they were diagnosed as "overweight/obese." Most patients (63 %) reported being "extremely comfortable" discussing weight with providers. Patients with higher BMI had higher levels of internalized weight bias (p < .001) and wanted their provider to "discuss weight sensitively" (p < .05). CONCLUSION: This study suggests that patients have important preferences that providers should be mindful of when discussing weight. While these discussions can be challenging, most patients report that they would be comfortable having these conversations directly and most would have enhanced motivation and confidence following these conversations. Communicating about weight is needed and desired by patients; doing so sensitively with those at higher weight is essential.

Do patients receiving hemodialysis regret starting dialysis? A survey of affected patients
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AIMS: End-stage renal disease (ESRD) is associated with high morbidity and mortality. A prior study showed that many Canadian patients regretted their decision to start dialysis. We sought to determine if US patients also regretted dialysis. MATERIALS AND METHODS: We surveyed hemodialysis patients within 55 miles of Rochester, MN, with a 25-question survey about their perceptions of their health, preparedness for dialysis, advance care planning, and regrets about starting dialysis. Surveys were administered in person at the patients' usual dialysis session from July 1 through December 1, 2014; responses were captured electronically. RESULTS: Of the 198 eligible patients, 128 participated (70% men); 80% received dialysis for more than 1 year; 38% reported their health and 58% described their quality of life as "good" or "very good"; 51% had started dialysis in the hospital; and 68% agreed they were prepared for what to expect. Only 35% of patients reported being offered supportive care without dialysis. Most patients (82%) recalled a discussion about prognosis. Only 43% completed an advance directive, but 72% thought it was at least "very important" to plan for the end of life. Nine (7%) reported regretting the decision to start dialysis. CONCLUSIONS: Most of our patients were optimistic about their health and prognosis. Few regretted the decision to start dialysis.
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Arguing the case for the autotaxin-lysophosphatidic acid-lipid phosphate phosphatase 3-signaling nexus in the development and complications of atherosclerosis.

The structurally simple glycero- and sphingo-phospholipids, lysophosphatidic acid (LPA) and sphingosine-1-phosphate, serve as important receptor-active mediators that influence blood and vascular cell function and are positioned to influence the events that contribute to the progression and complications of atherosclerosis. Growing evidence from preclinical animal models has implicated LPA, LPA receptors, and key enzymes involved in LPA metabolism in pathophysiologic events that may underlie atherosclerotic vascular disease. These observations are supported by genetic analysis in humans implicating a lipid phosphate phosphatase as a novel risk factor for coronary artery disease. In this review, we summarize current understanding of LPA production, metabolism, and signaling as may be relevant for atherosclerotic and other vascular disease.

Lipid phosphate phosphatase 3 negatively regulates smooth muscle cell phenotypic modulation to limit intimal hyperplasia.

OBJECTIVE: The lipid phosphate phosphatase 3 (LPP3) degrades bioactive lysophospholipids, including lysophosphatidic acid and sphingosine-1-phosphate, and thereby terminates their signaling effects. Although emerging evidence links lysophosphatidic acid to atherosclerosis and vascular injury responses, little is known about the role of vascular LPP3. The goal of this study was to determine the role of LPP3 in the development of vascular neointima formation and smooth muscle cells (SMC) responses. METHODS AND RESULTS: We report that LPP3 is expressed in vascular SMC after experimental arterial injury. Using gain- and loss-of-function approaches, we establish that a major function of LPP3 in isolated SMC cells is to attenuate proliferation (extracellular signal-regulated kinases) activity, Rho activation, and migration in response to serum and lysophosphatidic acid. These effects are at least partially a consequence of LPP3-catalyzed lysophosphatidic acid hydrolysis. Mice with selective inactivation of LPP3 in SMC display an exaggerated neointimal response to injury. CONCLUSIONS: Our observations suggest that LPP3 serves as an intrinsic negative regulator of SMC phenotypic modulation and inflammation after vascular injury, in part, by regulating lysophospholipid signaling. These findings may provide a mechanistic link to explain the association between a PPAP2B polymorphism and coronary artery disease risk.

The prevalence and contents of advance directives in patients with pacemakers.

BACKGROUND: Little is known about the use of advance directives (ADs) in patients who have implantable cardiac pacemakers (PMs). METHODS: We conducted a retrospective review of the medical records of residents of Olmsted County, Minnesota, who underwent implantation of a cardiac PM at Mayo Clinic (Rochester, Minnesota) during 2006 and 2007, and determined the prevalence and contents of ADs in these patients. RESULTS: During the study period, 205 residents of Olmsted County (men, 53%) underwent PM implantation (mean age [standard deviation] at implantation, 77 [15] years). Overall, 120 patients (59%) had ADs. Of these, 63 ADs (53%) were executed more than 12 months before and 33 (28%) were executed after PM implantation. Many patients specifically mentioned life-prolonging treatments in their ADs: cardiopulmonary resuscitation, 76 (63%); mechanical ventilation, 56 (47%); and hemodialysis, 31 (26%). Pain control was mentioned in 79 ADs (66%) and comfort measures were mentioned in 42 ADs (35%). Furthermore, the AD of many patients contained a general statement about end-of-life care (e.g., no "heroic measures"). However, only one AD (1%) specifically addressed the end-of-life management of the PM. CONCLUSIONS: More than half of the patients with PMs in our study had executed an AD, but only one patient specifically mentioned her PM in her AD. These results suggest that patients with PMs should be encouraged to execute ADs and specifically address end-of-life device management in their ADs. Doing so may prevent end-of-life ethical dilemmas related to PM management.

"It's not broke, so let's not try to fix it": why patients decline a cardiovascular implantable electronic device.

BACKGROUND: Few patients decline therapy of a cardiovascular implantable electronic device (CIED), and little is known about the characteristics or reasoning of those who do. Our objective was to describe the reasons why patients decline CIED implantation using qualitative methods. METHODS: Qualitative, engaging thematic analysis. Three patient focus groups led by two trained facilitators and one semi-structured interview guide. RESULTS: Of the 13 patients, two were women and all were white (median age [range], 65 [44-88] years). Five themes emerged: (1) don't mess with a good thing; (2) my health is good enough; (3) independent decision making; (4) it's your job, but it's my choice; and (5) gaps in learning. Most patients who decline CIEDs are asymptomatic. Other reasons to decline included feeling well, enjoying life, acceptance of the future, desire to try to improve health through diet and exercise, hearing of negative CIED experiences, and unwillingness to take on associated risks of CIED implantation. A medical record review showed that clinicians understand patients' reasons for declining CIED treatment. However, focus group data suggest that gaps in patients' knowledge around the purpose and function of CIEDs exist and patients may benefit from targeted education. CONCLUSIONS: Patients decline implantation of CIEDs for various reasons. Most patients who decline therapy are asymptomatic at the time of their device consult. Focus group information show data suggestive that device consultations should be enhanced to address gaps in patient learning and confirm knowledge transfer. Clinicians should revisit treatment options iteratively.