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Childhood obesity is at crisis levels in the United States. Risk factors for obesity can begin as early as infancy. Approximately 12 million children up to five years of age spend about 22.5 hours per week in child care centers where they receive a significant portion of their daily nutrition. Child care center personnel may not know how to select nutritious meal and snack choices. A health sciences librarian, a child care center director, and a dietitian designed an outreach program on nutrition that helped child care center teachers gain increased nutrition literacy. The teachers indicated that they gained increased personal understanding of formerly confusing nutrition issues (e.g., how to read a nutrition label and what defines a whole grain). Teachers were also able to identify aspects of web sites linked from MedlinePlus that indicated the sites served as reliable sources of health information. [ABSTRACT FROM PUBLISHER]

Play therapy is a highly adaptable treatment method that can be modified according to children’s ages, circumstances, and settings in which counseling occurs. Play therapy may be used in schools, community settings, and homes to help children following the death of a significant other. After reviewing basic developmental factors that affect children’s ability to comprehend the meaning of death, the article discusses the special circumstances of grief in different situations, including community-based counseling after Hurricane Katrina, school-based group play therapy following a teacher’s death, and conjoint parent-child play therapy after a father’s death in a terrorist attack. Increasing the acceptability and effectiveness of play therapy, professionals must consider and incorporate family and community traditions and beliefs. Additionally, professionals are encouraged to support teachers and parents in utilizing play-based activities to facilitate children’s expressions of grief. [ABSTRACT FROM PUBLISHER]

Different types of expressive therapies permit bereaved children to express and process their feelings through a variety of child-friendly non-verbal methods such as art, creative writing, and music. The selection of a particular method depends on considerations related to the particular needs of each child, the circumstances of the death, and the family/community narrative about it. This article demonstrates how expressive therapies may be used in individual, family, or group sessions which, through play and other modes of expression, provide children with an opportunity to communicate feelings about and reactions to their bereavement experiences in symbolic form. [ABSTRACT FROM AUTHOR]

The author reflects on the assistance provided by the child welfare practitioners in dealing with young people who have traumatic histories. She points out the need to understand the behavior of the problematic child to overcome the suffered violence. Further, she suggests extending a deeper understanding on the nature of the parents' background to assure effectivity of the intended service. INSET: Screening tool in primary care visits uncovers substance use.

In response to the COVID-19 pandemic, during the Spring 2020 semester universities cancelled campus activities and moved all instruction online resulting in significant changes for college students. This study examined COVID-related concerns, engagement in preventive behaviors, barriers to academic success, and the impact of the pandemic on academic performance and career plans among 743 undergraduate students. Highest concerns were expressed for health of family and the pandemic's economic effects. Over 70% reported engaging in preventive behaviors, with hand washing, wearing a face mask, and social distancing most prevalent. Despite anxiety, distracted home environments, and time management difficulties, most students indicated a relatively small effect of the pandemic on their academic success and anticipated career choice. Significant relationships were found between concern for contracting the virus and engaging in preventive behaviors, and between perceived barriers to academic success and change in academic performance. [ABSTRACT FROM AUTHOR]

Serum amyloid A (SAA) is a family of proteins, the plasma levels of which may increase >1000-fold in acute inflammatory states. We investigated the role of SAA in sepsis using mice deficient in all three acute-phase SAA isoforms (SAA-TKO). SAA deficiency significantly increased mortality rates in the three experimental sepsis mouse models: cecal ligation and puncture (CLP), cecal slurry (CS) injection, and lipopolysaccharide (LPS) treatments. SAA-TKO mice had exacerbated lung pathology compared to wild-type (WT) mice after CLP. A bulk RNA sequencing performed on lung tissues excised 24 h after CLP indicated significant enrichment in the expression of genes associated with chemokine production, chemokine and cytokine-mediated signaling, neutrophil chemotaxis, and neutrophil migration in SAA-TKO compared to WT mice. Consistently, myeloperoxidase activity and neutrophil counts were significantly increased in the lungs of septic SAA-TKO mice compared to WT mice. The in vitro treatment of HL-60, neutrophil-like cells, with SAA or SAA bound to a high-density lipoprotein (SAA-HDL), significantly decreased cellular transmigration through laminin-coated membranes compared to untreated cells. Thus, SAA potentially prevents neutrophil transmigration into injured lungs, thus reducing exacerbated tissue injury and mortality. In conclusion, we demonstrate for the first time that endogenous SAA plays a protective role in sepsis, including ameliorating lung injury. [ABSTRACT FROM AUTHOR]

The article reports on results of a study which outlines an approach to block the development of unstable plaques by reducing their inflammation. A description of the experimental set-up and measurement method is presented. The study investigates the role of the enzyme lipoprotein-associated phospholipase A2 (Lp-PLA2) in atherosclerotic plaque formation.

Serum amyloid A (SAA) is a high-density apolipoprotein whose plasma levels can increase more than 1000-fold during a severe acute-phase inflammatory response and are more modestly elevated in chronic inflammation. SAA is thought to play important roles in innate immunity, but its biological activities have not been completely delineated. We previously reported that SAA deficiency protects mice from developing abdominal aortic aneurysms (AAAs) induced by chronic angiotensin II (AngII) infusion. Here, we report that SAA is required for AngII-induced increases in interleukin-1β (IL-1β), a potent proinflammatory cytokine that is tightly controlled by the Nod-like receptor protein 3 (NLRP3) inflammasome and caspase-1 and has been implicated in both human and mouse AAAs. We determined that purified SAA stimulates IL-1β secretion in murine J774 and bone marrow–derived macrophages through a mechanism that depends on NLRP3 expression and caspase-1 activity, but is independent of P2X7 nucleotide receptor (P2X7R) activation. Inhibiting reactive oxygen species (ROS) by N-acetyl-l-cysteine or mito-TEMPO and inhibiting activation of cathepsin B by CA-074 blocked SAA–mediated inflammasome activation and IL-1β secretion. Moreover, inhibiting cellular potassium efflux with glyburide or increasing extracellular potassium also significantly reduced SAA–mediated IL-1β secretion. Of note, incorporating SAA into high-density lipoprotein (HDL) prior to its use in cell treatments completely abolished its ability to stimulate ROS generation and inflammasome activation. These results provide detailed insights into SAA–mediated IL-1β production and highlight HDL's role in regulating SAA's proinflammatory effects. [ABSTRACT FROM AUTHOR]

Group X secretory phospholipase A2 (GX sPLA2) hydrolyzes mammalian cell membranes, liberating free fatty acids and lysophospholipids. GX sPLA2 is produced as a pro-enzyme (pro-GX sPLA2) that contains an N-terminal 11-amino acid propeptide ending in a dibasic motif, suggesting cleavage by a furin-like proprotein convertase (PC). Although propeptide cleavage is clearly required for enzymatic activity, the protease(s) responsible for pro-GX sPLA2 activation have not been identified. We previously reported that GX sPLA2 negatively regulates adrenal glucocorticoid production, likely by suppressing liver X receptor-mediated activation of steroidogenic acute regulatory protein expression. In this study, using a FLAG epitope-tagged pro-GX sPLA2 expression construct (FLAG-pro-GX sPLA2), we determined that adrenocorticotropic hormone (ACTH) enhanced FLAG-pro-GX sPLA2 processing and phospholipase activity secreted by Y1 adrenal cells. ACTH increased the expression of furin and PCSK6, but not other members of the PC family, in Y1 cells. Overexpression of furin and PCSK6 in HEK 293 cells significantly enhanced FLAG-pro-GX sPLA2 processing, whereas siRNA-mediated knockdown of both PCs almost completely abolished FLAG-pro-GX sPLA2processing in Y1 cells. Expression of either furin or PCSK6 enhanced the ability of GX sPLA2 to suppress liver X receptor reporter activity. The PC inhibitor decanoyl-Arg-Val-Lys-Arg-chloromethyl ketone significantly suppressed FLAG-pro-GX sPLA2 processing and sPLA2 activity in Y1 cells, and it significantly attenuated GX sPLA2-dependent inhibition of steroidogenic acute regulatory protein expression and progesterone production. These findings provide strong evidence that pro-GX sPLA2 is a substrate for furin and PCSK6 proteolytic processing and define a novel mechanism for regulating corticosteroid production in adrenal cells. [ABSTRACT FROM AUTHOR]

Several studies in the past have reported positive correlations between circulating Serum amyloid A (SAA) levels and obesity. However, based on limited number of studies involving appropriate mouse models, the role of SAA in the development of obesity and obesity-related metabolic consequences has not been established. Accordingly, herein, we have examined the role of SAA in the development of obesity and its associated metabolic complications in vivo using mice deficient for all three inducible forms of SAA: SAA1.1, SAA2.1 and SAA3 (TKO). Male and female mice were rendered obese by feeding a high fat, high sucrose diet with added cholesterol (HFHSC) and control mice were fed rodent chow diet. Here, we show that the deletion of SAA does not affect diet-induced obesity, hepatic lipid metabolism or adipose tissue inflammation. However, there was a modest effect on glucose metabolism. The results of this study confirm previous findings that SAA levels are elevated in adipose tissues as well as in the circulation in diet-induced obese mice. However, the three acute phase SAAs do not play a causative role in the development of obesity or obesity-associated adipose tissue inflammation and dyslipidemia. [ABSTRACT FROM AUTHOR]

Introduction: Prolonged exercise requires increased utilization of blood glucose and adjustment of glucoregulatory hormones. Estrogen can reduce hepatic gluconeogenesis which could affect insulin concentrations. Amylin is co-secreted with insulin and controls influx of glucose into the blood. Purpose: To determine the effect of menstrual cycle stage on glucose, leptin, and pancreatic hormone responses to prolonged (90 min) exercise. Methods: Five healthy, eumenorrheic women (24.6 ± 5.1 years; 67.4 ± 1 kg) were monitored for 3 months to determine menstrual cycle length. Subjects completed a preliminary session to determine exercise workloads and, in a fasted condition, completed two randomized 90-min treadmill exercise trials at 60 % VO during the early follicular (EFX) and mid-luteal phase (MLX) of their menstrual cycle. Blood samples were analyzed for glucose, insulin, C-peptide, amylin, glucagon, leptin, and cortisol concentrations at rest (−30 and 0 min), during exercise (18, 36, 54, 72, and 90 min) and after 20 min of recovery. Results: No changes in amylin, leptin, or cortisol occurred for EFX and MLX trials. A significant ( p < 0.05) time effect occurred for glucose, insulin, and glucagon with reduced insulin across the exercise trial and increases in glucose and glucagon later in the trial, but there were no differences between the EFX and MLX trials. Conclusions: Menstrual cycle stage does not affect glucose, insulin, C-peptide, amylin, glucagon, cortisol, and leptin responses to prolonged exercise; however, the exercise reduces insulin and increases glucose and glucagon concentrations. This is the first study to determine acute effects of exercise on amylin and other glucoregulatory hormone responses in women. [ABSTRACT FROM AUTHOR]

Accumulating evidence indicates that secretory phospholipase A2 (sPLA2) enzymes promote atherogenic processes. We have previously showed the presence of Group V sPLA2 (GV sPLA2) in human and mouse atherosclerotic lesions, its hydrolysis of low density lipoprotein (LDL) particles, and the ability of GV sPLA2-modified LDL (GV-LDL) to induce macrophage foam cell formation in vitro. The goal of this study was to investigate the mechanisms involved in macrophage uptake of GV-LDL. Peritoneal macrophages from C57BL/6 mice (wild type (WT)), C57BL/6 mice deficient in LDL receptor (LDLR-/-), or SR-A and CD36 (DKO) were treated with control LDL, GV-LDL, oxidized LDL (ox-LDL) or LDL aggregated by vortexing (vx-LDL). As expected, ox-LDL induced significantly more cholesterol ester accumulation in WT and LDLR-/- compared with DKO macrophages. In contrast, there was no difference in the accumulation of GV-LDL or vx-LDL in the three cell types. 125I-ox-LDL exhibited high affinity, saturable binding to WT cells that was significantly reduced in DKO cells. Vx-LDL and GV-LDL showed low affinity, non-saturable binding that was similar for both cell types, and significantly higher compared with control LDL. GV-LDL degradation in WT and DKO cells was similar. Analyses by confocal microscopy indicated a distinct intracellular distribution of Alexa-568-labeled GV-LDL and Alexa-488-labeled ox-LDL. Uptake of GV-LDL (but not ox-LDL or vx-LDL) was significantly reduced in cells preincubated with heparin or NaClO3, suggesting a role for proteoglycans in GV-LDL uptake. Our data point to a physiological modification of LDL that has the potential to promote macrophage foam cell formation independent of scavenger receptors. [ABSTRACT FROM AUTHOR]

Obesity increases the risk for abdominal aortic aneurysms (AAA) in humans and enhances angiotensin II (AngII)-induced AAA formation in C57BL/6 mice. We reported that deficiency of Serum Amyloid A (SAA) significantly reduces AngII-induced inflammation and AAA in both hyperlipidemic apoE-deficient and obese C57BL/6 mice. The aim of this study is to investigate whether SAA plays a role in the progression of early AAA in obese C57BL/6 mice. Male C57BL/6J mice were fed a high-fat diet (60% kcal as fat) throughout the study. After 4 months of diet, the mice were infused with AngII until the end of the study. Mice with at least a 25% increase in the luminal diameter of the abdominal aorta after 4 weeks of AngII infusion were stratified into 2 groups. The first group received a control antisense oligonucleotide (Ctr ASO), and the second group received ASO that suppresses SAA (SAA-ASO) until the end of the study. Plasma SAA levels were significantly reduced by the SAA ASO treatment. While mice that received the control ASO had continued aortic dilation throughout the AngII infusion periods, the mice that received SAA-ASO had a significant reduction in the progression of aortic dilation, which was associated with significant reductions in matrix metalloprotease activities, decreased macrophage infiltration and decreased elastin breaks in the abdominal aortas. We demonstrate for the first time that suppression of SAA protects obese C57BL/6 mice from the progression of AngII-induced AAA. Suppression of SAA may be a therapeutic approach to limit AAA progression. [Display omitted] • Plasma SAA levels. • Matrix metalloprotease activities in the abdominal aorta. • Macrophage infiltration in the abdominal aorta. • The progression of aortic dilation and limited the progression of the disease. [ABSTRACT FROM AUTHOR]

Background and aims Serum amyloid A (SAA) predicts cardiovascular events. Overexpression of SAA increases atherosclerosis development; however, deficiency of two of the murine acute phase isoforms, SAA1.1 and SAA2.1, has no effect on atherosclerosis. SAA3 is a pseudogene in humans, but is an expressed acute phase isoform in mice. The goal of this study was to determine if SAA3 affects atherosclerosis in mice. Methods ApoE -/- mice were used as the model for all studies. SAA3 was overexpressed by an adeno-associated virus or suppressed using an anti-sense oligonucleotide approach. Results Over-expression of SAA3 led to a 4-fold increase in atherosclerosis lesion area compared to control mice ( p = 0.01). Suppression of SAA3 decreased atherosclerosis in mice genetically deficient in SAA1.1 and SAA2.1 ( p < 0.0001). Conclusions SAA3 augments atherosclerosis in mice. Our results resolve a previous paradox in the literature and support extensive epidemiological data that SAA is pro-atherogenic. [ABSTRACT FROM AUTHOR]

High-density lipoproteins (HDLs) protect against atherosclerosis by removing excess cholesterol from macrophages through the ATP-binding cassette transporter A1 (ABCA1) and ATP-binding cassette transporter G1 (ABCG1) pathways involved in reverse cholesterol transport. Factors that impair the availability of functional apolipoproteins or the activities of ABCA1 and ABCG1 could, therefore, strongly influence atherogenesis. HDL also inhibits lipid oxidation, restores endothelial function, exerts anti-inflammatory and antiapoptotic actions, and exerts anti-inflammatory actions in animal models. Such properties could contribute considerably to the capacity of HDL to inhibit atherosclerosis. Systemic and vascular inflammation has been proposed to convert HDL to a dysfunctional form that has impaired antiatherogenic effects. A loss of anti-inflammatory and antioxidative proteins, perhaps in combination with a gain of proinflammatory proteins, might be another important component in rendering HDL dysfunctional. The proinflammatory enzyme myeloperoxidase induces both oxidative modification and nitrosylation of specific residues on plasma and arterial apolipoprotein A-I to render HDL dysfunctional, which results in impaired ABCA1 macrophage transport, the activation of inflammatory pathways, and an increased risk of coronary artery disease. Understanding the features of dysfunctional HDL or apolipoprotein A-I in clinical practice might lead to new diagnostic and therapeutic approaches to atherosclerosis. [ABSTRACT FROM AUTHOR]

Group X secretory phospholipase A2 (GX sPLA2) potently hydrolyzes membrane phospholipids to release arachidonic acid (AA). While AA is an activator of glucose-stimulated insulin secretion (GSIS), its metabolite prostaglandin E2 (PGE2) is a known inhibitor. In this study, we determined that GX sPLA2 is expressed in insulin-producing cells of mouse pancreatic islets and investigated its role in beta cell function. GSIS was measured in vivo in wild-type (WT) and GX sPLA2-deficient (GX KO) mice and ex vivo using pancreatic islets isolated from WT and GX KO mice. GSIS was also assessed in vitro using mouse MIN6 pancreatic beta cells with or without GX sPLA2 overexpression or exogenous addition. GSIS was significantly higher in islets isolated from GX KO mice compared with islets from WT mice. Conversely, GSIS was lower in MIN6 cells overexpressing GX sPLA2 (MIN6-GX) compared with control (MIN6-C) cells. PGE2 production was significantly higher in MIN6-GX cells compared with MIN6-C cells and this was associated with significantly reduced cellular cAMP. The effect of GX sPLA2 on GSIS was abolished when cells were treated with NS398 (a COX-2 inhibitor) or L-798,106 (a PGE2-EP3 receptor antagonist). Consistent with enhanced beta cell function, GX KO mice showed significantly increased plasma insulin levels following glucose challenge and were protected from age-related reductions in GSIS and glucose tolerance compared with WT mice. We conclude that GX sPLA2 plays a previously unrecognized role in negatively regulating pancreatic insulin secretion by augmenting COX-2-dependent PGE2 production. [ABSTRACT FROM AUTHOR]

Group X secretory phospholipase A2 (GX sPLA2) potently hydrolyzes membrane phospholipids to release arachidonic acid (AA). While AA is an activator of glucose-stimulated insulin secretion (GSIS), its metabolite prostaglandin E2 (PGE2) is a known inhibitor. In this study, we determined that GX sPLA2 is expressed in insulin-producing cells of mouse pancreatic islets and investigated its role in beta cell function. GSIS was measured in vivo in wild-type (WT) and GX sPLA2-deficient (GX KO) mice and ex vivo using pancreatic islets isolated from WT and GX KO mice. GSIS was also assessed in vitro using mouse MIN6 pancreatic beta cells with or without GX sPLA2 overexpression or exogenous addition. GSIS was significantly higher in islets isolated from GX KO mice compared with islets from WT mice. Conversely, GSIS was lower in MIN6 cells overexpressing GX sPLA2 (MIN6-GX) compared with control (MIN6-C) cells. PGE2 production was significantly higher in MIN6-GX cells compared with MIN6-C cells and this was associated with significantly reduced cellular cAMP. The effect of GX sPLA2 on GSIS was abolished when cells were treated with NS398 (a COX-2 inhibitor) or L-798,106 (a PGE2-EP3 receptor antagonist). Consistent with enhanced beta cell function, GX KO mice showed significantly increased plasma insulin levels following glucose challenge and were protected from age-related reductions in GSIS and glucose tolerance compared with WT mice. We conclude that GX sPLA2 plays a previously unrecognized role in negatively regulating pancreatic insulin secretion by augmenting COX-2-dependent PGE2 production. [ABSTRACT FROM AUTHOR]

A correction to the article "No Effect of Menstrual Cycle Phase on Glucose and Glucoregulatory Endocrine Responses to Prolonged Exercise" by Robert R. Kraemer and colleagues, published online on July 25, 2013, is presented.

This article presents a review of data in literature that deal with the function of high-density lipoprotein (HDL). It explores the potential contribution of functional assays to understanding the mechanisms of atherosclerotic cardiovascular disease (CVD). It also discusses the involvement of the proteome and lipidome in HDL structure-function relationships.

Abstract: SAA has been shown to have potential proinflammatory properties in inflammatory diseases such as atherosclerosis. These include induction of tumor necrosis factor α, interleukin-6, and monocyte chemoattractant protein 1 in vitro. However, concern has been raised that these effects might be due to use of recombinant SAA with low level of endotoxin contaminants or its non-native forms. Therefore, physiological relevance has not been fully elucidated. In this study, we investigated the role of SAA in the production of inflammatory cytokines. Stimulation of mouse monocyte J774 cells with lipid-poor recombinant human SAA and purified SAA derived from cardiac surgery patients, but not ApoA-I and ApoA-II, elicited pro-inflammatory cytokines like granulocyte colony stimulating factor (G-CSF). However, HDL-associated SAA failed to stimulate production of these cytokines. Using neutralizing antibodies against toll like receptor (TLR) 2 and 4, we could evaluate that TLR 2 is responsible for G-CSF production by lipid-poor SAA. To confirm these data in vivo, we expressed mouse SAA in SAA deficient C57BL/6 mice using an adenoviral vector. G-CSF was identically expressed in SAA-Adenoviral infected mice as well as in control null-Adenoviral mice at the early time points (4–8h) and could not be detected in plasma 24h after infection when plasma SAA levels were maximally elevated, indicating that adenoviral vector rather than SAA affected G-CSF levels. Taken together, our findings suggest that lipid-poor SAA, but not HDL-associated SAA, stimulates G-CSF production and this stimulation is mediated through TLR 2 in J774 cells. However, its physiological role in vivo remains ambiguous. [Copyright &y& Elsevier]

Studies suggest that inflammation impairs reverse cholesterol transport (RCT). We investigated whether serum amyloid A (SAA) contributes to this impairment using an established macrophage-to-feces RCT model. Wild-type (WT) mice and mice deficient in SAA1.1 and SAA2.1 (SAAKO) were injected intraperitoneally with ³H-cholesterol-labeled J774 macrophages 4hr after administration of LPS or buffered saline. ³H-cholesterol in plasma 4hr after macrophage injection was significantly reduced in both WT and SAAKO mice injected with LPS, but this was not associated with a reduced capacity of serum from LPS-injected mice to promote macrophage cholesterol efflux in vitro. Hepatic accumulation of ³H-cholesterol was unaltered in either WT or SAAKO mice by LPS treatment. Radioactivity present in bile and feces of LPS-injected WT mice 24hr after macrophage injection was reduced by 36% (P < 0.05) and 80% (P < 0.001), respectively. In contrast, in SAAKO mice, LPS did not significantly reduce macrophage-derived ³H-cholesterol in bile, and fecal excretion was reduced by only 45% (P < 0.05). Injection of cholesterol-loaded allogeneic J774 cells, but not syngeneic bone-marrow-derived macrophages, transiently induced SAA in C57BL/6 mice. Our study confirms reports that acute inflammation impairs steps in the RCT pathway and establishes that SAA plays only a minor role in this impairment. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To investigate the mechanisms by which macrophage scavenger receptor BI (SR-BI) regulates macrophage cholesterol homeostasis and protects against atherosclerosis. Methods and results: The expression and function of SR-BI was investigated in cultured mouse bone marrow-derived macrophages (BMM). SR-BI, the other scavenger receptors SRA and CD36 and the ATP-binding cassette transporters ABCA1 and ABCG1 were each distinctly regulated during BMM differentiation. SR-BI levels increased transiently to significant levels during culture. SR-BI expression in BMM was reversibly down-regulated by lipid loading with modified LDL; SR-BI was shown to be present both on the cell surface as well as intracellularly. BMM exhibited selective HDL CE uptake, however, this was not dependent on SR-BI or another potential candidate glycosylphosphatidylinositol anchored high density lipoprotein binding protein 1 (GPIHBP1). SR-BI played a significant role in facilitating bidirectional cholesterol flux in non lipid-loaded cells. SR-BI expression enhanced both cell cholesterol efflux and cholesterol influx from HDL, but did not lead to altered cellular cholesterol mass. SR-BI-dependent efflux occurred to larger HDL particles but not to smaller HDL3. Following cholesterol loading, ABCA1 and ABCG1 were up-regulated and served as the major contributors to cholesterol efflux, while SR-BI expression was down-regulated. Conclusion: Our results suggest that SR-BI plays a significant role in macrophage cholesterol flux that may partly account for its effects on atherogenesis. [Copyright &y& Elsevier]

Secretory phospholipase A2s (sPLA2) hydrolyze glycerophospholipids to liberate lysophospholipids and free fatty acids. Although group X (GX) sPLA2 is recognized as the most potent mammalian sPLA2 in vitro, its precise physiological function(s) remains unclear. We recently reported that GX sPLA2 suppresses activation of the liver X receptor in macrophages, resulting in reduced expression of liver X receptor-responsive genes including ATP-binding cassette transporters A1 (ABCA1) and G1 (ABCG1), and a consequent decrease in cellular cholesterol efflux and increase in cellular cholesterol content (Shridas et al. 2010. Arterioscler. Thromb. Vasc. Biol. 30: 2014-2021). In this study, we provide evidence that GX sPLA2 modulates macrophage inflammatory responses by altering cellular cholesterol homeostasis. Transgenic expression or exogenous addition of GX sPLA2 resulted in a significantly higher induction of TNF-α, IL-6, and cyclooxygenase-2 in J774 macrophage-like cells in response to LPS. This effect required GX sPLA2 catalytic activity, and was abolished in macrophages that lack either TLR4 or MyD88. The hypersensitivity to LPS in cells overexpressing GX sPLA2 was reversed when cellular free cholesterol was normalized using cyclodextrin. Consistent with results from gain-of-function studies, peritoneal macrophages from GX sPLA2-deficient mice exhibited a significantly dampened response to LPS. Plasma concentrations of inflammatory cytokines were significantly lower in GX sPLA2-deficient mice compared with wild-type mice after LPS administration. Thus, GX sPLA2 amplifies signaling through TLR4 by a mechanism that is dependent on its catalytic activity. Our data indicate this effect is mediated through alterations in plasma membrane free cholesterol and lipid raft content. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Abdominal aortic aneurysm (AAA) is a complex vascular disease characterized by matrix degradation and inflammation and is a major cause of mortality in older men. Specific interventions that prevent AAA progression remain to be identified. In this study, we tested the hypothesis that Group X secretory phospholipase A2 (GX sPLA2), an enzyme implicated in inflammatory processes, mediates AAA. Methods and results: GX sPLA2 was detected by immunostaining in human aneurysmal tissue and in angiotensin II (Ang II)-induced AAAs in apolipoprotein E-deficient (apoE−/−) mice. GX sPLA2 mRNA was increased significantly (11-fold) in abdominal aortas of apoE−/− mice in response to Ang II infusion. To define the role of GX sPLA2 in experimental AAAs, apoE−/− and apoE−/− x GX sPLA2 −/− (GX DKO) mice were infused with Ang II for either 10 (n =7) or 28 (n =24–26) days. Deficiency of GX sPLA2 significantly reduced the incidence and severity of AAAs, as assessed by ultrasound measurements in vivo of aortic lumens and by computer-assisted morphometric analyses ex vivo of external diameter. Results from gene expression profiling indicated that the expression of specific matrix metalloproteinases and inflammatory mediators was blunted in aortas from GX DKO mice compared to apoE−/− mice after 10-day Ang II infusion. Ang II induction of cyclooxygenase-2, interleukin-6, matrix metalloproteinase (MMP)-2, MMP-13 and MMP-14 was reduced significantly in GX DKO mice compared to apoE−/− mice. Conclusion: GX sPLA2 promotes Ang II-induced pathological responses leading to AAA formation. [ABSTRACT FROM AUTHOR]

Studies in vitro indicate that group X secretory phospholipase A2 (GX sPLA2) potently releases arachidonic acid (AA) and lysophosphatidylcholine from mammalian cell membranes. To define the function of GX sPLA2 in vivo, our laboratory recently generated C57BL/6 mice with targeted deletion of GX sPLA2 (GX-/- mice). When fed a normal rodent diet, GX-/- mice gained significantly more weight and had increased adiposity compared to GX+/+ mice, which was not attributable to alterations in food consumption or energy expenditure. When treated with adipogenic stimuli ex vivo, stromal vascular cells isolated from adipose tissue of GX-/- mice accumulated significantly more (20%) triglyceride compared to cells from GX+/+ mice. Conversely, overexpression of GX sPLA2 but not catalytically inactive GX SPLA2, resulted in a significant 50% reduction in triglyceride accumulation in OP9 adipocytes. The induction of genes encoding adipogenic proteins (PPARγ, SREBP-1c, SCD1, and FAS) was also significantly blunted by 50-80% in OP9 cells overexpressing GX sPLA2. Activation of the liver X receptor (LXR), a nuclear receptor known to up-regulate adipogenic gene expression, was suppressed in 3T3-L1 and OP9 cells when GX sPLA2 was overexpressed. Thus, hydrolytic products generated by GX sPLA2, negatively regulate adipogenesis, possibly by suppressing LXR activation. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Previous studies have established that hydrolysis of LDL by Group V secretory phospholipase A2 (GV sPLA2) generates a modified particle capable of inducing macrophage foam cell formation. The aim of the present study was to determine whether GV sPLA2-hydrolyzed LDL (GV-LDL) produces pro-atherogenic effects in macrophages independent of cholesterol accumulation. Methods and results: J-774 cells incubated with GV-LDL produced more TNF-α and IL-6 compared to cells incubated with control-LDL. Indirect immunofluorescence showed that GV-LDL but not control-LDL induced nuclear translocation of NFκB. Inhibitors of NFκB activation, effectively blocked cytokine production induced by GV-LDL. Control-LDL and GV-LDL were separated from albumin present in reaction mixtures by ultracentrifugation. The albumin fraction derived from GV-LDL contained 80% of the FFA generated and was more potent than the re-isolated GV-LDL in inducing pro-inflammatory cytokine secretion. Linoleic acid (18:2) and oleic acid (18:1) were the most abundant FFAs generated, whereas newly formed lyso-PCs contained 14:0 (myristic), 16:1 (palmitic), and 18:2 fatty acyl groups. Experiments with synthetic FFA showed that 18:1 induced J-774 cells to secrete TNF-α and IL-6. Conclusions: These results indicate that in addition to promoting atherosclerotic lipid accumulation in macrophages, GV sPLA2 hydrolysis of LDL leads to activation of NFκB, a key regulator of inflammation. [Copyright &y& Elsevier]

In AIDS Clinical Trials Group A5095, 9% of participants who experienced an adverse event related to efavirenz substituted nevirapine. Most adverse events resolved; 15 participants ultimately discontinued nevirapine therapy. Grade 3/4 hepatotoxicity was observed in 14% of individuals who substituted nevirapine, compared with 6% who continued efavirenz therapy. Substitution of nevirapine because of efavirenz toxicity was generally safe and efficacious. [ABSTRACT FROM AUTHOR]

The article assesses the metabolic changes after initiation of protease inhibitor-sparing regimens in antiretroviral-naive patients. Metabolic changes were analyzed within the triple-nucleoside-containing, three-drug efavirenz-containing, and four-drug efavirenz-containing arms of the AIDS Clinical Trials Group multicenter trial A5095.

The high density lipoprotein (HDL) receptor Scavenger Receptor BII (SR-BII) is encoded by an alternatively spliced mRNA from the SR-BI gene and is expressed in various tissues. SR-BII protein differs from SR-BI only in the carboxyl-terminal cytoplasmic tail, which, as we showed previously, must contain a signal that confers predominant intracellular expression and rapid endocytosis of HDL. We have shown that SR-BII mediates HDL endocytosis through a clathrin-dependent, caveolae-independent pathway. Two candidate amino acid motifs were identified in the tail that could mediate association with clathrin-containing endocytic vesicles: a putative dileucine motif at position 492–493 and an overlapping tyrosine-based YXXZ motif starting at position 489. Although substitution of tyrosine at position 489 with alanine or histidine did not affect endocytosis, substitution L492A resulted in increased surface binding of HDL and reduced HDL particle endocytosis. Substitution L493A had a less dramatic effect. No other regions in the carboxyl-terminal tail appeared to contain motifs required for HDL endocytosis. Substitutions of leucine at position 492 with the hydrophobic amino acids valine or phenylalanine also reduced HDL endocytosis, stressing the importance of leucine at this position. Introducing the SR-BII YTPLL motif into the carboxyl-terminal cytoplasmic tail of SR-BI converted SR-BI into an endocytic receptor resembling SR-BII. These results demonstrated that SR-BII differs from SR-BI in subcellular localization and trafficking and suggest that the two isoforms differ in the manner in which they target ligands intracellularly. [ABSTRACT FROM AUTHOR]

Scavenger receptor class B, type I (SR-BI) mediates selective uptake of high density lipoprotein (HDL) lipids. It is unclear whether this process occurs at the cell membrane or via endocytosis. Our group previously identified an alternative mRNA splicing variant of SRBI, named SR-BII, with an entirely different, yet highly conserved cytoplasmic C terminus. In this study we aimed to compare HDL uptake by both isoforms. Whereas SR-BI was mainly (∼70%) localized on the surface of transfected Chinese hamster ovary cells, as determined by biotinylation, HDL binding at 4 °C, and studies of enhanced green fluorescent protein-tagged SR-BI/II fusion proteins, the majority of SR-BII (∼8090%) was expressed intracellularly. The cellular distribution of SR-BI was not affected by deletion of the C terminus, which suggests that the distinct C terminus of SR-BII is responsible for its intracellular expression. Pulse-chase experiments showed that SR-BII rapidly internalized HDL protein, whereas in the case of SR-BI most HDL protein remained surface bound. Like its ligand, SR-BII was more rapidly endocytosed compared with SR-BI. Despite more rapid HDL uptake by SR-BII than SR-BI, selective cholesteryl ether uptake was significantly lower. Relative to their levels of expression at the cell surface, however, both isoforms mediated selective uptake with similar efficiency. HDL protein that was internalized by SR-BII largely co-localized with transferrin in the endosomal recycling compartment. Within the endosomal recycling compartment of SR-BII cells, there was extensive co-localization of internalized HDL lipid and protein. These results do not support a model that selective lipid uptake by SR-BI requires receptor/ligand recycling within the cell. We conclude that SR-BII may influence cellular cholesterol trafficking and homeostasis in a manner that is distinct from SR-BI. [ABSTRACT FROM AUTHOR]

This article focuses on the alcoholics perception of the ward as a predictor of aftercare attendance. The sample was selected from 90 alcoholic inpatients admitted to an 8-week Substance Abuse Program at the Veterans Administration Hospital in Miami, Florida. A number of demographic characteristics such as age, race, marital status, income, education and work history were collected upon admission to the inpatient treatment program. In addition, variables such as number of previous hospitalizations, number of convictions, motivation, and additional data related to the patient's alcoholism were obtained.