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Aims One unaddressed aspect of healing after myocardial infarction (MI) is how non-myocyte cells that survived the ischemic injury, keep withstanding additional cellular damage by stress forms typically arising during the post-infarction inflammation. Here we aimed to determine if cell survival is conferred by expression of a mitochondrial protein novel to the cardiac proteome, known as steroidogenic acute regulatory protein, (StAR/STARD1). Further studies aimed to unravel the regulation and role of the non-steroidogenic cardiac StAR after MI. Methods and results Following permanent ligation of the left anterior descending coronary artery in mouse heart, timeline western blot analyses showed that StAR expression corresponds to the inflammatory response to MI. Following the identification of StAR in mitochondria of cardiac fibroblasts in culture, confocal microscopy immunohistochemistry (IHC) identified StAR expression in left ventricular (LV) activated interstitial fibroblasts, adventitial fibroblasts and endothelial cells. Further work with the primary fibroblasts model revealed that interleukin-1α (IL-1α) signaling via NF-κB and p38 MAPK pathways efficiently upregulates the expression of the Star gene products. At the functional level, IL-1α primed fibroblasts were protected against apoptosis when exposed to cisplatin mimicry of in vivo apoptotic stress; yet, the protective impact of IL-1α was lost upon siRNA mediated StAR downregulation. At the physiological level, StAR expression was nullified during post-MI inflammation in a mouse model with global IL-1α deficiency, concomitantly resulting in a 4-fold elevation of apoptotic fibroblasts. Serial echocardiography and IHC studies of mice examined 24 days after MI revealed aggravation of LV dysfunction, LV dilatation, anterior wall thinning and adverse tissue remodeling when compared with loxP control hearts. Conclusions This study calls attention to overlooked aspects of cellular responses evolved under the stress conditions associated with the default inflammatory response to MI. Our observations suggest that LV IL-1α is cardioprotective, and at least one mechanism of this action is mediated by induction of StAR expression in border zone fibroblasts, which renders them apoptosis resistant. This acquired survival feature also has long-term ramifications on the heart recovery by diminishing adverse remodeling and improving the heart function after MI.

Background and aims Mediterranean diet has been associated with decreased cardiovascular morbidity and mortality. Both fish and olive oil are key components of this diet. Therefore, we compared their effects on nonalcoholic fatty liver disease (NAFLD) and atherogenesis in a mouse model, fed a high fat diet. Methods and results Forty nine, female LDL receptor knockout (LDLR KO) mice were allocated into 3 groups and fed an atherogenic high fat (HF) diet for 9 weeks. The HF group was fed a high fat diet alone. A HF + OO group was fed a HF diet with added olive oil (60 ml/kg feed), and the third group (HF + FO) was fed a HF diet with added fish oil (60 ml/kg feed). Both additions of fish and olive oil, significantly decreased plasma cholesterol elevation compared to HF diet. Nevertheless, only fish oil addition reduced significantly atherosclerotic lesion area by 51% compared to HF group. Liver levels of eicosapentenoic (EPA) and docosahexaenoic (DHA) acids were several folds higher in HF + FO group than in HF and HF + OO groups. Liver levels of oleic acid were higher in HF + OO compared to the other groups. Moreover, Fish oil addition significantly decreased NAFLD scores related to steatosis and inflammation and lowered the expression of the inflammatory genes interleukin 6 (IL6) and monocyte chemoattractant protein 1 (MCP1). Conclusion These results suggest that fish oil addition on top of an atherogenic, HF diet, is beneficial, while olive oil is not, in its effect on plaque formation and NAFLD in LDLR KO mice.

Despite the impressive decline in mortality from atherosclerotic cardiovascular diseases (ASCVD), these diseases still account for a large proportion of the overall morbidity and mortality worldwide. A vast amount of research has demonstrated the key role played by circulating lipoproteins, and especially low-density lipoprotein (LDL), in the etiology of atherosclerosis, and numerous studies have proven the efficacy of interventions that lower the atherogenic lipoproteins in reducing morbidity and mortality from ASCVD. While previous guidelines placed an emphasis on the use HMG-CoA reductase inhibitors (statins) for the treatment of dyslipidemia, recent studies have shown that other LDL cholesterol lowering drugs, including ezetimibe and the PCSK9 inhibitors, can provide additional benefit when used in combination with (and in certain cases instead of) statins. These studies have also shown that blood LDL cholesterol levels lower than previously recommended targets provide additional benefit, without evidence of a threshold beyond which the benefit ceases and without excess adverse effects. The updated guidelines were formulated by a committee that consisted of representatives from the Israeli Society for the Research, Prevention and Treatment of Atherosclerosis, the Israel Society of Internal Medicine, the Israeli Heart Association, the Israeli Neurology Association and the Israel Association of Family Medicine. They provide recommendations for revised risk stratification of patients, novel target goals, and the use of evidence-based treatment and follow-up strategies with reference to specific patient sub-groups.

Vitamin A deficiency (VAD) is a major health problem, especially in developing countries. In this study, we investigated the effect of VAD from weaning to adulthood in apoE-/- mice. Three-week-old male mice were allocated into four diet groups: I. VAD II. VAD+vitamin A (VA), 1500 IU retinyl-palmitate, III. VAD+&beta, carotene (BC), 6 g/kg feed, containing 50% all-trans and 50% 9-cis BC. IV. VAD with BC and VA (BC+VA). After 13 weeks, we assessed the size of atherosclerotic plaques and measured VA in tissues and BC in plasma and tissues. VAD resulted in diminished hepatic VA levels and undetectable brain VA levels compared to the other groups. BC completely replenished VA levels in the liver, and BC+VA led to a two-fold elevation of hepatic VA accumulation. In adipose tissue, mice fed BC+VA accumulated only 13% BC compared to mice fed BC alone. Atherosclerotic lesion area of BC group was 73% lower compared to VAD group (p &lt, 0.05). These results suggest that BC can be a sole source for VA and inhibits atherogenesis.

Maternal docosahexaenoic acid (DHA) is required during pregnancy to supply for normal fetal growth and development. This pilot study aimed to assess the unknown fatty acid (FA) composition in a cohort of non-pregnant and pregnant Israeli women at term and their offspring on a normal diet without n-3 FA supplementation. The fatty acid profile, analyzed using gas chromatography, showed significantly higher plasma monounsaturated (MUFA) and lower n-6 FA percent distribution with similar n-3 index, in pregnant compared to non-pregnant women. RBC exhibited significantly higher MUFA with similar n-3 index, in pregnant compared to non-pregnant women. N-3 FA significantly correlated between neonates’ plasma, with higher n-3 index, and pregnant women's DHA. Conclusion: DHA levels in non-pregnant and pregnant Israeli women at term were comparable and the DHA in pregnant women's plasma positively correlated with their neonate's level, suggesting an efficient mother-fetus FA transfer and/or fetal fatty acid metabolism to longer FA products.

Docosahexaenoic acid (DHA) is critical for normal brain development and function. DHA is in danger of being significantly reduced in the human food supply, and the question of whether its metabolic precursor, the essential n-3 alpha linolenic acid (ALA) during pregnancy, can support fetal brain DHA levels for optimal neurodevelopment, is fundamental. Female mice were fed either ALA-enriched or Control diet during pregnancy and lactation. The direct effect of maternal dietary ALA on lipids was analyzed in liver, red blood cells, brain and brain vasculature, together with genes of fatty acid metabolism and transport in three-week-old offspring. The long-term effect of maternal dietary ALA on brain fatty acids and memory was studied in 19-week-old offspring. Three-week-old ALA offspring showed higher levels of n-3 fatty acids in liver, red blood cell, blood-brain barrier (BBB) vasculature and brain parenchyma, DHA enrichment in brain phospholipids and higher gene and protein expression of the DHA transporter, major facilitator superfamily domain containing 2a, compared to Controls. 19-week-old ALA offspring showed higher brain DHA levels and better memory performance than Controls. The increased brain DHA levels induced by maternal dietary ALA during pregnancy-lactation, together with the up-regulated levels of major facilitator superfamily domain containing 2a, may indicate a mode for greater DHA uptake with long-term impact on better memory in ALA offspring.

Hypertension, advanced age, postprandial hyperlipidemia, and insulin resistance are major risk factors for atherosclerosis. The calcium channel blocker nifedipine is reported to ameliorate insulin resistance possibly by activating PPARγ. This is expected to become accentuated in elderly individuals due to age-related insulin resistance. Insulin resistance modulates lipoprotein metabolism. Therefore, we reasoned that nifedipne offers the potential for improving postprandial lipemia in association with increasing age. We studied the effect of nifedipine on fasting lipids, postprandial lipemia, insulin sensitivity, and plasma lipolytic activity in 24 and 15 hypertensive subjects aged 70-75 years and 40-45 years, respectively. As expected, nifedipine significantly lowered systolic and diastolic blood pressure. Nifedipine decreased fasting triglyceride level (23%) and increased HDL-C (15%) in the elderly group. At baseline, postprandial triglyceride levels were remarkably elevated in elderly compared to younger patients (1 288±798 vs. 501±260 mg·dl(-1)·h, p

Purpose Lipoxygenases (LOX) have been implicated in carcinogenesis, however both pro- and anti-carcinogenic effects have been reported in different cancer models. Using transgenic mice, which specifically overexpress human 15-lipoxygenase (ALOX15) in endothelial cells (EC), we previously demonstrated significant inhibition of tumor development. In the Lewis lung carcinoma (LLC) model, the primary tumor developed similarly in both wild type (WT) and ALOX15 overexpressing mice. However, metastases development was significantly inhibited in the transgenic mice. Here, we explored the molecular basis for the anti-metastatic effect of endothelial cell specific ALOX15 overexpression. Materials/methods We used ALOX15 overexpressing mice, and in-vitro cell model to evaluate the molecular effect of ALOX15 on EC and LLC cells. Results When LLC cells were injected in WT and ALOX15 overexpressing mice, we observed a higher degree of apoptosis and necrosis in primary and metastatic tumors of ALOX15 overexpressing animals. These anti-carcinogenic and anti-metastatic effects were paralleled by augmented expression of cyclin-dependent kinase inhibitor 1A (CDKN1A; p21) and of the peroxisome proliferators-activated receptor (PPAR)γ and by downregulation of the steady state concentrations of connexin26 mRNA. Consistent with these in vivo effects, ALOX15 overexpression in LLC and HeLa cancer cells in vitro significantly reduced cell viability in culture. In contrast, similar treatment of non-cancerous B2B epithelial cells did not impact cell viability. Conclusions Taken together, our data suggests that endothelial cell specific overexpression of ALOX15 promotes apoptosis and necrosis in primary and metastatic tumors in mice, by upregulation of P21 and PPARγ expression in adjacent cancer cells.

Klotho is a transmembrane protein, expressed mainly in the kidneys and the choroid plexus. The extracellular domain of klotho is composed of 2 internal repeats, KL1 and KL2, which can be cleaved and act as hormones. Klotho-deficient mice develop a phenotype resembling human aging. Laboratory and clinical data suggest a favorable effect of klotho on atherosclerosis, high blood pressure, and metabolic syndrome. Therefore, we aimed to study the effect of klotho treatment on atherogenesis, blood pressure, and metabolic parameters in experimental rodent models. Fructose-fed Sprague-Dawley rats (metabolic syndrome model) and apolipoprotein E (apoE -/-) knock-out mice (atherosclerosis model) were treated with either klotho or its active domain KL1. In apoE -/- mice, klotho unexpectedly elevated plasma cholesterol and triglyceride levels compared to the control group. Yet, it did not increase the aortic sinus atherosclerotic lesion area. In fructose-fed Sprague-Dawley rats, klotho treatment did not lower blood pressure or plasma triglyceride levels. Although KL1 treatment did not lower blood pressure or plasma insulin levels, it significantly reduced the elevation of total plasma triglyceride levels (from 2.3-fold to 1.6-fold, p0.05) due to lower triglyceride-rich VLDL levels. Klotho did not show any beneficial effects on atherosclerosis and components of the metabolic syndrome and was associated with increased plasma cholesterol levels. On the other hand, treatment with KL1 may lower plasma triglyceride levels independent of insulin. Additional studies are required in order to decipher the complex role of klotho and its active domains in the regulation of plasma lipid levels.

Background: Several epidemiological studies have shown that diets rich in carotenoids are associated with a reduced risk of cardiovascular disease. However, administration of synthetic all-trans -carotene was reported to have no effect on cardiovascular disease. We previously showed that the 9-cis -carotene-rich powder of the alga Dunaliella bardawil inhibits atherogenesis and reduces plasma non-HDL cholesterol levels in mice. Context and purpose of this study: We sought to study whether isolated 9-cis -carotene inhibits atherogenesis in a murine model of atherosclerosis. Results: Twelve-week-old female LDL receptor knockout mice (LDLR-/-) were pretreated for 2 weeks with regular chow diet fortified with the alga Dunaliella powder, 9-cis β-carotene isomer, all-trans β-carotene isomer, or 9-cis retinoic acid, followed by 10 weeks of a high-fat diet with the same fortifications. In contrast to Dunaliella, 9-cis β-carotene did not inhibit the high fat dietinduced elevation of plasma cholesterol. In addition, diet fortification with Dunaliella powder, β-carotene isomers, or 9-cis retinoic acid did not change the plasma retinol or retinoic acid levels.Nevertheless, 9-cis β-carotene significantly inhibited atherogenesis compared to the control mice (39% reduction). Conclusions: The results suggest that 9-cis β-carotene should be considered as an antiatherogenic agent in the human diet

High plasma levels of LDL-cholesterol play a causative role in atherogenesis. The first step in atherogenesis is characterized by oxidation of retained LDL particles in the arterial wall, and scavenger receptors-mediated entry of oxidized-LDL into macrophages, resulting in the accumulation of cholesterol within macrophages. Therefore, cholesterol efflux from macrophages to HDL particles is an essential process in inhibiting the formation of atherosclerotic plaques. Previous in-vitro experiments conducted in our laboratory, revealed that 9-cis β-carotene (9CBC) enhanced the efflux of radioactively labeled cholesterol from macrophages to HDL. However, the mechanism by which 9CBC enhances cholesterol efflux remained obscure. We found, in a controlled in-vitro assay, that treating macrophages both with the Dunaliella bardawil alga derived carotenoid 9CBC, and 22R-hydroxycholesterol (22-HC), two ligands of the nuclear receptors Retinoid X Receptor (RXR) and Liver X Receptor (LXR) respectively, resulted in a synergistically increase in fluorescently-labeled cholesterol efflux. Moreover, concurrent treatment of 9CBC with liarozole, which blocks the metabolism of Retinoic Acid (RA), increased cholesterol efflux from macrophages. This result strengthens our hypothesis that 9CBC activates the RXR nuclear receptor by its conversion to RA. Furthermore, cholesterol efflux was greater in macrophages isolated from alga Dunaliella-fed WT or apoE-/- mice compared to chow diet-fed mice. Our results suggest that simultaneous activation of nuclear receptors affects regulation of cellular cholesterol and may accelerate reverse cholesterol transport, by increasing cholesterol efflux from macrophages and thus, reducing the risk for atherogenesis.

ObjectiveWhile extensive research revealed that interleukin (IL)-1β contributes to insulin resistance (IR) development, the role of IL-1α in obesity and IR was scarcely studied. Using control, whole body IL-1α knockout (KO) or myeloid-cell-specific IL-1α-deficient mice, we tested the hypothesis that IL-1α deficiency would protect against high-fat diet (HFD)-induced obesity and its metabolic consequences.Research design and methodsTo induce obesity and IR, control and IL-1α KO mice were given either chow or HFD for 16 weeks. Glucose tolerance test was performed at 10 and 15 weeks, representing early and progressive stages of glucose intolerance, respectively. Liver and epididymal white adipose tissue (eWAT) samples were analyzed for general morphology and adipocyte size. Plasma levels of adiponectin, insulin, total cholesterol and triglyceride (TG), lipoprotein profile as well as hepatic lipids were analyzed. Expression of lipid and inflammation-related genes in liver and eWAT was analyzed. Primary mouse hepatocytes isolated from control mice were treated either with dimethyl sulfoxide (DMSO) (control) or 20 ng/mL recombinant IL-1α for 24 hours and subjected to gene expression analysis.ResultsAlthough total body weight gain was similar, IL-1α KO mice showed reduced adiposity and were completely protected from HFD-induced glucose intolerance. In addition, plasma total cholesterol and TG levels were lower and HFD-induced accumulation of liver TGs was completely inhibited in IL-1α KO compared with control mice. Expression of stearoyl-CoA desaturase1 (SCD1), fatty acid synthase (FASN), elongation of long-chain fatty acids family member 6 (ELOVL6), acetyl-CoA carboxylase (ACC), key enzymes that promote de-novo lipogenesis, was lower in livers of IL-1α KO mice. Treatment with recombinant IL-1α elevated the expression of ELOVL6 and FASN in mouse primary hepatocytes. Finally, mice with myeloid-cell-specific deletion of IL-1α did not show reduced adiposity and improved glucose tolerance.ConclusionsWe demonstrate a novel role of IL-1α in promoting adiposity, obesity-induced glucose intolerance and liver TG accumulation and suggest that IL-1α blockade could be used for treatment of obesity and its metabolic consequences.

Statins are considered very effective in reducing cardiovascular morbidity and mortality in high-risk patients. However, although adherence to statins improves morbidity and mortality (1), it remains suboptimal (2). One of the most important causes of nonadherence is the so-called statin intolerance, mainly because of muscle-related symptoms. These symptoms most often consist of myalgia unaccompanied by significant creatine kinase (CK) elevations. Less often, myositis (elevated CK >10 times the upper limit of normal) or rhabdomyolysis (CK level >10,000 IU/L or accompanied by significant elevation in creatinine level) develops. In randomized controlled trials, the incidence of statin myopathy is ~1.5–5.0% (3). However, this low incidence may be misleading for several reasons. First, in most studies patients with a history of statin intolerance were excluded. Other studies had a single-blinded statin run-in phase, and patients experiencing muscle-related symptoms or CK elevations during this phase were excluded. Patients who tend to be at risk for developing muscle-related symptoms, such as women, elderly patients, and patients with significant comorbidity, who comprise a large proportion of statin-treated patients in real-life settings, are underrepresented in randomized controlled trials. Some studies have defined muscle-related effects by elevated CK levels only, disregarding myalgia. Last but not least, patients enrolled in studies might be motivated and so minimize reporting of mild myalgias, thus leading to underestimation of the magnitude of the problem. Data concerning real-life incidence of statin-related myopathy are scarce. In the Prediction of Muscular Risk in Observational Conditions (PRIMO) study (4), 7,924 patients receiving high-dosage statin therapy in an outpatient setting in France were asked about muscle-related symptoms. Overall, muscular symptoms were reported by 10.5% of the patients. A weakness of this study is that it lacked a comparison/control group not treated with statins. In a study of adults aged ≥40 years who participated in National Health and …

Background Kidney transplant patients are a unique population where despite correction of their kidney function they are still considered to be at high cardiovascular (CV) risk. Adiponectin, an adipokine secreted from adipocytes, has protective CV properties. Patients with essential hypertension (HTN) have low adiponectin levels that are associated with a high CV risk. The aim of this study was to assess adiponectin levels in hypertensive renal transplant recipients. Materials and methods Fasting blood adiponectin levels were measured in hypertensive kidney transplant patients (n = 18), patients with essential HTN (n = 17) and healthy subjects (n = 14). Patients with diabetes mellitus and renal failure were excluded from the study. Anthropomorphic and metabolic parameters were also measured. Results Patients with essential HTN had lower adiponectin levels than healthy controls (6 ± 0.7 μg/mL vs. 11 ± 0.9 μg/mL, p

Follicle-stimulating hormone receptor (FSHR) is a pivotal regulator of ovarian response to hormonal stimulation. Inflammatory conditions have been linked to lower FSHR expression in granulosa cells (GCs) as well as an attenuated response to hormonal stimulation. The current study aimed to reveal if deficiency and/or blockage of the pro-inflammatory cytokine interleukin 1-alpha (IL1A) increased Fshr expression in rodent GCs. We found elevated Fshr transcript abundance, as assessed by quantitative PCR, in primary GCs isolated from Il1a-knockout compared to wild-type mice, and that the expression of FSHR is significantly higher in Il1a-knockout compared to wild-type ovaries. Supplementing GC cultures with recombinant IL1A significantly lowered Fshr expression in these cells. In accordance with the Fshr expression pattern, proliferation of GCs was higher in follicles from Il1a-knockout mice compared to wild-type mice, as indicated by the MKI67 immunohistochemical staining. Furthermore, treating wild-type mice with anakinra, an IL1 receptor 1 antagonist, significantly increased the expression of Fshr in primary GCs from treated compared to control mice. These data highlight an important interdependency between the potent pro-inflammatory cytokine IL1A and Fshr expression.

Cholesterol efflux from macrophages is a key process in reverse cholesterol transport and, therefore, might inhibit atherogenesis. 9-cis-β-carotene (9-cis-βc) is a precursor for 9-cis-retinoic-acid (9-cis-RA), which regulates macrophage cholesterol efflux. Our objective was to assess whether 9-cis-βc increases macrophage cholesterol efflux and induces the expression of cholesterol transporters. Enrichment of a mouse diet with βc from the alga Dunaliella led to βc accumulation in peritoneal macrophages. 9-cis-βc increased the mRNA levels of CYP26B1, an enzyme that regulates RA cellular levels, indicating the formation of RA from βc in RAW264.7 macrophages. Furthermore, 9-cis-βc, as well as all-trans-βc, significantly increased cholesterol efflux to high-density lipoprotein (HDL) by 50% in RAW264.7 macrophages. Likewise, food fortification with 9-cis-βc augmented cholesterol efflux from macrophages ex vivo. 9-cis-βc increased both the mRNA and protein levels of ABCA1 and apolipoprotein E (APOE) and the mRNA level of ABCG1. Our study shows, for the first time, that 9-cis-βc from the diet accumulates in peritoneal macrophages and increases cholesterol efflux to HDL. These effects might be ascribed to transcriptional induction of ABCA1, ABCG1, and APOE. These results highlight the beneficial effect of βc in inhibition of atherosclerosis by improving cholesterol efflux from macrophages.

Several species of the alga Dunaliella contain high levels of β-carotene. Low dietary β-carotene intake is associated with type 2 diabetes. Dunaliella contains high levels of all-trans and 9-cis isomers of β-carotene and is the best known naturally occurring nutritional source of 9-cis β-carotene. Since vitamin A has been suggested to play a role in glucose and lipid metabolism, we aimed to study the effect of Dunaliella supplementation on diabetes in mice. Ten diabetic db/db mice were fed chow diet fortified with 8 % 9-cis-rich Dunaliella powder. Ten db/db and heterozygous db/+ mice each served as controls and were fed chow diet alone. The control db/db mice developed severe hyperglycemia with fasting glucose levels reaching 400 mg dL−1. Dunaliella significantly inhibited the elevation of plasma glucose (p = 0.007). The area under the curve of the glucose tolerance test was 24 % lower in Dunaliella-treated mice than in the control db/db mice. Triglyceride elevation was significantly lower in the Dunaliella group than in the db/db group (p = 0.007). The mRNA levels of several pro-inflammatory genes in adipose tissue, including monocyte chemotactic protein-1, intercellular adhesion molecule, vascular adhesion molecule-1, receptor-associated protein factor 6, and p-selectin, were elevated in the db/db group as compared to the db/+, whereas their levels were significantly lower in the Dunaliella-treated group. These results suggest that 9-cis β-carotene-rich Dunaliella may inhibit diabetes in db/db mice by reducing inflammation in adipose tissue. This study also emphasizes the importance of β-carotene isomers in our diet.

Objective Apolipoprotein A–V plays an important role in reducing plasma triglyceride levels. We hypothesized that expression of apoA–V would inhibit atherogenesis in apoE −/− mice fed chow diet which is a known model of hypercholesterolemia. Our aim was to study this protective effect and to explore possible mechanisms. Methods and results ApoA–V +/+ ApoE −/− mice expressing human apolipoprotein A–V ( h apoA–V) were generated and compared to apoE −/− mice. Atherosclerotic aortic sinus lesion area was 70% smaller in h apoA–V +/+ apoE −/− . This was accompanied by a 58% reduction in lesion macrophage content. Furthermore, advanced atherosclerotic lesions in h apoA–V +/+ apoE −/− mice showed features of a more stable plaque, manifested by 59% and 37% higher collagen and α-actin content, respectively. Plasma triglyceride and cholesterol levels in h apoA–V +/+ apoE −/− mice were 47% and 33% lower, respectively. These were associated with a 33% reduction in very low density lipoprotein triglyceride production and 2-fold acceleration in triglyceride-rich lipoprotein clearance in h apoA–V +/+ apoE −/− mice. In addition, h apoA–V +/+ apoE −/− mice showed enhanced insulin sensitivity (25% and 15% improvement in glucose tolerance and insulin responsiveness, respectively). Finally, h apoA–V +/+ apoE −/− displayed a milder systemic inflammatory response compared to apoE −/− mice, manifested by 22%, 65% and 15% lower plasma levels of TNFα, IL-1β and IL-6, respectively. Conclusions We showed that human apolipoprotein A–V is a potent modulator of atherosclerosis in mice through multiple modes of action. These findings may identify apoA–V as a potential therapeutic target for treatment of atherosclerosis.

Objectives Interleukin (IL)-1 produced by vascular and bone marrow-derived cells exerts proinflammatory effects in these cell types by binding to IL-1 receptor type-1 (IL-1R1). We have previously shown that bone marrow-derived IL-1α and IL-1β are critical for atherogenesis in apoE knockout (KO) mice. The aim of the present study was to investigate whether IL-1R1 on vascular wall resident or bone marrow-derived cells mediates IL-1's effects in atherogenesis. Methods and results We generated apoE−/−/IL-1R1−/− double knockout (DKO) mice and created radiation chimeras. Aortic sinus lesion area was 20–47% lower in DKO compared to apoE KO mice with similar plasma lipids. The production of IL-1α and IL-1β upon stimulation with LPS was not altered in IL-1R1−/− compared to IL-1R1+/+ peritoneal macrophages. DKO mice transplanted with IL-1R1+/+ bone marrow-derived cells had reduced (48%) aortic sinus lesion compared to apoE KO mice while specific deficiency of IL-1R1 in bone marrow-derived cells did not attenuate atherosclerosis. The mRNA levels of genes that promote macrophage recruitment to the vascular wall, namely CD68, VCAM-1, ICAM-1 and MCP-1 were lower in aortas from DKO compared to apoE KO mice. Finally, blockade of IL-1R1 with IL-1R antagonist (IL-1Ra) resulted in complete abrogation of IL-1β-induced expression of adhesion and chemotactic molecules and IL-1α, in isolated human umbilical vein endothelial cells (HUVEC). Conclusions Vascular wall resident cells are the main targets for the pro-atherogenic effects of bone marrow-derived IL-1 through IL-1R1, partly by induction of adhesion and chemotactic molecules in endothelial cells.

AIMS To determine whether low-dose calcitriol attenuates atherosclerosis in apoE-null mice and, if so, through which predominant mechanism. METHODS Starting at the age of 6 weeks, mice received intraperitoneal injections of either 0.25 ng/g body weight of calcitriol or the vehicle, every other day for 8 weeks. RESULTS Calcitriol treatment resulted in 35% reduction of atherosclerosis at the aortic sinus, and in a significant decrease in blood pressure. These effects were possibly mediated by downregulation of the renin-angiotensin system (RAS), as there was a 64% decrease in the aortic level of renin mRNA. None of the other components of the RAS or the prorenin receptor were affected by treatment. Low-dose calcitriol treatment did not modify the plasma level of monocyte chemoattractant protein-1, interferon γ, interleukin-4 and interleukin-10, which were similar in control and treated mice. Likewise, there was no difference in the percentage of splenic Foxp3+ regulatory T cells. Calcitriol treatment resulted in an unfavorable metabolic profile (glucose and lipids), as determined after a limited fast, a difference that disappeared after food was withheld for a longer time. CONCLUSIONS At a relatively low dosage, calcitriol attenuates the development of atherosclerosis in apoE-null mice, most probably by down regulation of RAS, and not through immunomodulation; however, even at this low dose, calcitriol appears to elevate calcium and to have potentially adverse metabolic effects. Exploring the potential antiatherogenic effects of non-calcemic and safer analogues is therefore warranted.

Diabetes carries a high risk of atherosclerosis, and cardiovascular disease, especially coronary heart disease (CHD) and stroke, is by far the leading cause of death among patients with type 2 diabetes. Although statins reduce the risk of major vascular events by about one-fifth per millimole per liter reduction in LDL cholesterol, with similar proportional reductions in major coronary events, stroke, and the need for coronary revascularization, the residual risk remains high. In the Scandinavian Simvastatin Survival Study (4S) (1), although the relative risk reduction in diabetic patients was larger than in nondiabetic patients, simvastatin-treated diabetic patients were still at higher risk of death than the placebo-treated nondiabetic patients. Multifactorial intervention reduces the risk even further, but significant danger remains. Current guidelines call for an aggressive treatment strategy to reduce LDL cholesterol, blood pressure, and glucose levels in diabetic patients, but data concerning the management of high triglyceride (TG) levels and low HDL cholesterol levels remains inconclusive. This article reviews the data concerning diabetic dyslipidemia and its management. The cluster of lipid abnormalities associated with type 2 diabetes is defined by a high concentration of TG and small dense LDL and a low concentration of HDL cholesterol. Plasma LDL cholesterol levels are generally normal. Insulin resistance is believed to contribute to this atherogenic dyslipidemia by increasing the hepatic secretion of VLDL and other apolipoprotein (apo)B-containing lipoprotein particles, as a result of increased free fatty acid flux to the liver (2,3). This may also be the result of a diminished suppressive effect of insulin on apoB secretion, either at the level of the regulation of apoB degradation, or inhibition of microsomal TG transfer protein activity (4). Through the action of cholesterol ester transfer protein, TGs are transferred from VLDL to HDL, creating TG-rich HDL particles, which are hydrolyzed by hepatic …

The prevalence of diabetes for all age-groups worldwide was estimated to be 2.8% (171 million) in the year 2000, and the projected number could rise to 4.4% (366 million) in 2030 (1). This rapid rise is mainly attributable to the increase of diabetes. The continuing escalation of obesity and the metabolic syndrome contribute to the upsurge in frequency of diabetes (2,3). Interestingly, the appreciation in the number of people >65 years of age was found to be the most important demographic change to diabetes prevalence around the world, indicating that the “diabetes epidemic” will continue even if levels of obesity remain constant. Therefore, it is likely that future diabetes preponderance is underestimated, given the growing frequency of obesity (1). Because the vast majority of diabetic patients have type 2 diabetes and almost all the studies were performed in such subjects, in this article, “type 2 diabetes” will be referred to as “diabetes.” Cardiovascular disease (CVD) is one of the foremost causes of mortality and is a major contributor to morbidity for individuals with diabetes. In addition, diabetes is an independent risk factor for macrovascular disease, as are the common coexisting conditions (hypertension and dyslipidemia). The U.K. Prospective Diabetes Study (UKPDS) evaluated baseline risk factors for coronary artery disease in patients with newly diagnosed diabetes without evidence of vascular disease. When comparing the relative contribution of the three modifiable coexisting conditions (dyslipidemia, hypertension, and hyperglycemia) with development of future coronary heart disease (CHD), the estimated hazard ratio (HR) for the upper third, relative to the lower third, for LDL cholesterol, systolic blood pressure, and A1C were 2.26, 1.82, and 1.52, respectively (4). This finding supports the notion that dyslipidemia, and specifically LDL cholesterol, are major contributors to the increased CHD risk in patients with diabetes (4,5 …

Adiponectin is an important vascular protective substance whose levels are reduced in states of insulin resistance. The relationships between plasma insulin levels and adiponectin are not fully understood, and it is not known whether it is the elevated circulating levels of insulin or insulin resistance that directly affects adiponectin levels. The present study evaluates the direct effect of chronic hyperinsulinemia on plasma adiponectin levels. Male Sprague-Dawley rats were treated with insulin (n=15) administered by a sustained-release implant or were given a sham implantation (n=10) as a control group. Body weight, systolic blood pressure, plasma glucose, triglycerides, insulin, and adiponectin were measured at baseline and after 20 and 40 d of treatment. Insulin-treated rats and controls showed a similar increase in body weight. The insulin-treated group had a significant increase in plasma insulin levels and a decrease in plasma glucose levels compared with the sham group, with no change in blood pressure or triglyceride levels. Adiponectin levels remained unchanged despite the significant increase in insulin levels. High circulating insulin levels do not affect plasma adiponectin levels. These results support the concept that the primary defect that results in insulin resistance and hyperinsulinemia is responsible for the altered plasma adiponectin levels in the metabolic syndrome and type 2 diabetes.

BACKGROUND Adiponectin is an adipose tissue-specific protein, which possesses anti-atherogenic and antidiabetic properties, yet its plasma levels are decreased in subjects with metabolic syndrome. Although high fat diet has been linked to hypoadiponectinemia, the effect of high-carbohydrate diet on adiponectin levels is not known. Therefore, we studied the effect of high-carbohydrate diet on adiponectin levels in the rat models of hypertension and insulin resistance. METHODS Rats were randomly assigned to the high carbohydrate diet [Sprague-Dawley rats with fructose enriched diet (SDR-F) and spontaneously hypertensive rats with sucrose enriched diet (SHR-S model)] or chow diet (Control group). Rats were followed for 6 weeks (SDR-F model) and 8 weeks (SHR-S model). Body weight, systolic blood pressure, plasma levels of glucose, insulin, triglycerides and adiponectin, were recorded. RESULTS Both models were associated with features of the metabolic syndrome, namely, high insulin levels, increased blood pressure and triglyceride levels. Plasma adiponectin levels did not change in the control groups. In contrast, adiponectin levels increased by 39 and 30% compared to baseline following four and six weeks of fructose enriched diet in SDR (from 3.3+/-0.2 to 4.5+/-0.4 and 4.3+/-0.2 microg/ml, respectively, p

The health hazard of the metabolic syndrome (MS) is increasing, yet there is no effective pharmacologic treatment to this entity as a whole. Recently, hypoadiponectinemia was found to play an important role in the development of MS. We studied the effect of the PPAR-gamma agonist rosiglitazone on adiponectin and the metabolic profile in the fructose-induced hypertensive, hyperinsulinemic, hypertriglyceridemic rat model.Thirty male Sprague-Dawley rats were divided into three groups. Ten were fed standard rat chow for 5 weeks, 10, a fructose-enriched diet for 5 weeks, and 10, a fructose-enriched diet for 5 weeks, with rosiglitazone 10 mg/kg/d added during the last 2 weeks. Blood pressure (BP), oral glucose tolerance test (OGTT), plasma insulin, triglycerides, and adiponectin were recorded, as well as mRNA levels of the adiponectin gene in visceral adipose tissue.Fructose-fed rats developed MS as manifested by the increase in systolic BP (from 139 +/- 3 to 158 +/- 4 mm Hg, P.05), insulin (from 26 +/- 1.6 to 40 +/- 2.5 muU/mL, P.05), triglycerides (from 91 +/- 9 to 304 +/- 24 mg/dL, P.05), and impaired OGTT (area under the curve from 13,894 +/- 246 to 17,725 +/- 700 mg/dL/min). Treatment with rosiglitazone reversed these effects and reduced BP to 133 +/- 7 mm Hg, insulin levels to 30 +/- 2.8 muU/mL, triglycerides to 116 +/- 9 mg/dL, and the OGTT to 15,415 +/- 372 mg/dL/min (P.05 for all variables). In addition, rosiglitazone increased plasma levels of adiponectin fourfold from 4.3 +/- 0.1 to 18.4 +/- 0.6 mug/mL (P.05). This increase was coupled with 3.8-fold increase in adiponectin mRNA in visceral adipose tissue.This study shows for the first time that in an animal model of MS, the insulin sensitizer, rosiglitazone, improves the metabolic profile and increases plasma levels of adiponectin and its gene expression. It is possible therefore that rosiglitazone exerts its beneficial effects by increasing the levels of adiponectin.

Diuretics are recommended as first-line antihypertensive treatment in elderly patients. Although attention is usually paid to prevent hypokalaemia with diuretic therapy, risk of hyponatraemia is often ignored. We performed this study to characterise hypertensive patients at increased risk to develop hyponatraemia. We reviewed charts of hypertensive patients hospitalised in Chaim Sheba Medical Center for hyponatraemia from 1990 to 1997. Patients with other causes of hyponatraemia were excluded. The General Practice Maccabi database was used to estimate age and sex distribution of patients prescribed diuretics for hypertension. We identified 180 hypertensive patients (149 F, 31 M; mean age 76.4 +/- 9.2 years) hospitalised because of hyponatraemia. Across all age groups, odds ratio (OR) to develop hyponatraemia was three times higher for women vs men (OR 3.10, 95% confidence interval (CI): 2.07-4.67). One hundred and sixty-two patients (90%) were older than 65 years. Patients of both sexes older than 65 years were 10 times (and if they were older than 75 years 16 times) more likely to develop hyponatraemia than those younger than 65 years (OR 9.87, 95%, CI: 5.93-16.64). Most patients (74.5%) used a thiazide-based diuretic; only 10% used a low dose (

Background and aims Fulminant hepatitis failure (FHF) is marked by the sudden loss of hepatic function, with a severe life-threatening course in persons with no prior history of liver disease. Interleukin (IL)-1α and IL-1β are key inflammatory cytokines but little is known about their role in the development of FHF. The aim of this study was to assess the involvement of IL-1α and IL-1β in the progression of LPS/GalN-induced FHF. Methods WT, IL-1α or IL-1β deficient mice were injected with LPS/GalN. Blood and liver tissue were collected at different time points, FHF related pathways were examined. Results After FHF induction the survival of both IL-1α and IL-1β KO mice was longer than that of WT mice. Lower serum liver enzyme levels, demonstrated reduced hepatic injury in the IL-1α and IL-1βKO mice. Histologically detected liver injury and apoptotic hepatocytes were significantly reduced in the IL-1αand IL-1βKO mice compared to WT mice. Reduced hepatic IkB levels and upregulated NFκB activity in WT mice remained inhibited in IL-1α and IL-1β KO mice. Hepatic expression levels of TNFα and IL-6 were significantly increased in WT mice but not in IL-1α and IL-1β KO mice. Conclusions IL-1α and IL-1β play a central role in the pathogenesis of LPS/GalN-induced FHF. These interleukins are associated with the activation of NFκB signaling, upregulation of the pro-inflammatory cytokines and liver damage and apoptosis. Since neither IL-1α nor IL-1β depletions completely rescued the phenotype, we believe that IL-1α and IL-1β have a similar and probably complementary role in FHF progression.

Oocyte endowment dwindles away during prepubertal and adult life until menopause occurs, and apoptosis has been identified as a central mechanism responsible for oocyte elimination. A few recent reports suggest that uncontrolled inflammation may adversely affect ovarian reserve. We tested the possible role of the proinflammatory cytokine IL-1 in the age-related exhaustion of ovarian reserve using IL-1α and IL-1β–KO mice. IL-1α–KO mice showed a substantially higher pregnancy rate and litter size compared with WT mice at advanced age. The number of secondary and antral follicles was significantly higher in 2.5-mo-old IL-1α–KO ovaries compared with WT ovaries. Serum anti-Mullerian hormone, a putative marker of ovarian reserve, was markedly higher in IL-1α–KO mice from 2.5 mo onward, along with a greater ovarian response to gonadotropins. IL-1β–KO mice displayed a comparable but more subtle prolongation of ovarian lifespan compared with IL-1α–KO mice. The protein and mRNA of both IL-1α and IL-1β mice were localized within the developing follicles (oocytes and granulosa cells), and their ovarian mRNA levels increased with age. Molecular analysis revealed decreased apoptotic signaling [higher B-cell lymphoma 2 (BCL-2) and lower BCL-2–associated X protein levels], along with a marked attenuation in the expression of genes coding for the proinflammatory cytokines IL-1β, IL-6, and TNF-α in ovaries of IL-1α–KO mice compared with WT mice. Taken together, IL-1 emerges as an important participant in the age-related exhaustion of ovarian reserve in mice, possibly by enhancing the expression of inflammatory genes and promoting apoptotic pathways.

IL-1α and IL-1β are synthesized as 31 kDa cell-associated precursors following TLR-4 stimulation, but their processing to the mature form and secretion require a second intracellular stimulus. The unique localization of the precursor of IL-1α (pro-IL-1α) to the nucleus suggested a role in transcriptional regulation of inflammatory cytokines. We explored the hypothesis that pro-IL-1α is involved in regulation of IL-1β expression following TLR-4 stimulation. IL-1β mRNA and protein levels were specifically decreased in macrophages from IL-1α-deficient mice following TLR-1/2, TLR-4 or TLR-9 stimulation, supporting the hypothesis. However, activation of the main upstream regulators of IL-1β expression, IRF3, NFkB and p38/JNK, were not reduced in macrophages from IL-1α-deficient mice. In order to assess the specific role of IL-1α in macrophages, we generated mice with myeloid cell deficiency of IL-1α (LyzMCre-loxp). Despite over 90% knockdown of IL-1α, TLR-4 stimulated macrophages from LyzMCre-loxp mice did not produce lower levels of IL-1β compared to IL-1α-loxp-flanked mice. In order to overcome the possibility that effects are caused by the incomplete deficiency of IL-1α, we generated new whole-body IL-1α knockout mice (GeneralCre-IL-1α) and the findings were similar to myeloid cell-deficient IL-1α. Collectively, our findings do not support the previously suggested role of nuclear IL-1α in gene regulation of IL-1β. Rather, they suggest that IL-1α acts mainly as an alarmin that is sequestered in the nucleus following stimulation with TLR-4.

Background & Aims ER stress promotes liver fat accumulation and induction of inflammatory cytokines, which contribute to the development of steatohepatitis. Unresolved ER stress upregulates the pro-apoptotic CHOP. IL-1α is localized to the nucleus in apoptotic cells, but is released when these cells become necrotic and induce sterile inflammation. We investigated whether IL-1α is involved in ER stress-induced apoptosis and steatohepatitis. Methods We employed WT and IL-1α-deficient mice to study the role of IL-1α in ER stress-induced steatohepatitis. Results Liver CHOP mRNA was induced in a time dependent fashion in the atherogenic diet-induced steatohepatitis model, and was twofold lower in IL-1α deficient compared to WT mice. In the ER stress-driven steatohepatitis model, IL-1α deficiency decreased the elevation in serum ALT levels, the number of apoptotic cells (measured as caspase-3-positive hepatocytes), and the expression of IL-1β, IL-6, TNFα, and CHOP, with no effect on the degree of fatty liver formation. IL-1α was upregulated in ER-stressed-macrophages and the protein was localized to the nucleus. IL-1β mRNA and CHOP mRNA and protein levels were lower in ER-stressed-macrophages from IL-1α deficient compared to WT mice. ER stress induced the expression of IL-1α and IL-1β also in mouse primary hepatocytes. Recombinant IL-1α treatment in hepatocytes did not affect CHOP expression but upregulated both IL-1α and IL-1β mRNA levels. Conclusion We show that IL-1α is upregulated in response to ER stress and IL-1α deficiency reduces ER stress-induced CHOP expression, apoptosis and steatohepatitis. As a dual function cytokine, IL-1α may contribute to the induction of CHOP intracellularly, while IL-1α released from necrotic cells accelerates steatohepatitis via induction of inflammatory cytokines by neighboring cells.

Background The role of Kupffer cell interleukin (IL)-1 in non-alcoholic steatohepatitis development remains unclear. Aims To evaluate the role of Kupffer cell IL-1α, IL-1β or IL-1 receptor type-1 (IL-1R1) in steatohepatitis. Methods C57BL/6 mice were irradiated and transplanted with bone marrow-derived cells from WT, IL-1α−/−, IL-1β−/− or IL-1R1−/− mice combined with Kupffer cell ablation with Gadolinium Chloride, and fed atherogenic diet. Plasma and liver triglycerides and cholesterol, serum alanine aminotransferase (ALT), liver histology and expression levels of inflammatory genes were assessed. Results The ablation and replacement of Kupffer cells with bone marrow-derived cells was confirmed. The atherogenic diet elevated plasma and liver cholesterol, reduced plasma and liver triglycerides and increased serum ALT levels in all groups. Steatosis and steatohepatitis were induced, but without liver fibrosis. A reduction in the severity of portal inflammation was observed only in mice with Kupffer cell deficiency of IL-1α. Accordingly, liver mRNA levels of inflammatory genes encoding for IL-1α, IL-1β, TNFα, SAA1 and IL-6 were significantly lower in mice with Kupffer cell deficiency of IL-1α compared to WT mice. Conclusion Selective deficiency of IL-1α in Kupffer cells reduces liver inflammation and expression of inflammatory cytokines, which may implicate Kupffer cell-derived IL-1α in steatohepatitis development.

Introduction.β-Carotene-rich diet has been shown to be inversely associated with the risk of coronary heart disease. However, clinical trials using synthetic all-trans-β-carotene failed to demonstrate a beneficial effect. We therefore sought to study the effect of natural source ofβ-carotene, the algaDunaliella, containing both all-trans and 9-cis-β-carotene on atherosclerosis. In a previous study we showed that 9-cis-β-carotene-rich powder of the algaDunaliellainhibits early atherogenesis in low-density lipoprotein receptor knockout mice.Aims. The aims of the current work were to study whether diet enriched withDunaliellapowder would inhibit the progression of established atherosclerosis in old male apoE-deficient mice and to compare the effect ofDunaliellaon lipid profile and atherosclerosis in a low-versus high-fat diet fed mice.Methods. In the first experiment, young mice (12 weeks old) were allocated into 3 groups: (1) low-fat diet; (2) low-fat diet + Dunaliellapowder (8%); (3) low-fat diet + β-carotene-deficientDunaliella. In the second experiment, old mice (7 months old) with established atherosclerotic lesions were allocated into 4 groups: (1) low-fat diet; (2) low-fat diet + Dunaliella; (3) high fat-diet; (4) high-fat diet + Dunaliella.Results. In young mice fed a low-fat diet, a trend toward lower atherosclerotic lesion area in the aortic sinus was found in theDunaliellagroup compared with the control group. In old mice with established atherosclerotic lesion,Dunaliellainhibited significantly plasma cholesterol elevation and atherosclerosis progression in mice fed a high-fat diet.Conclusion. The results of this study suggest that a diet containing natural carotenoids, rich in 9-cis-β-carotene, has the potential to inhibit atherosclerosis progression, particularly in high-fat diet regime.

article i nfo Objective: The acute effect of heparin on lipoprotein clearance is well characterized. Yet, the effect of prolonged low-molecular-weight-heparin (LMWH) administration on post-prandial lipemia has remained so far unex- plored. Recent reports suggest that LMWH could modify lipid and carbohydrate metabolism by diminishing TNFα-mediated inflammatory response. This, together with the known negative effect of TNF-α on insulin sen- sitivity, prompted us to hypothesize that LMWH would favorably affect post-prandial lipoprotein disposal. Methods: Twenty four patients were given a vitamin A-fat loading meal at the end of 6-week enoxaparin treat- ment and after 3-month washout period. Post-prandial lipemia was assessed by measuring retinyl-palmitate (RP) during 8 hours following the meal. Insulin sensitivity index (ISI), plasma lipolytic activity and plasma TNF-α were measured. Results: Enoxaparin did not impact fasting plasma lipids and lipoproteins levels. Enoxaparin increased RP clear- ance in the chylomicron remnant (CMR) fraction by 32% (P b 0.01). Additionally, enoxaparin decreased plasma TNF-α by 22% (P b 0.01), increased hepatic lipase (HL) activity by 81% (P b 0.01), along with a 2-fold increase in ISI (P b 0.01). The decrease in CMR correlated with the reduction in TNFα and the increase in ISI and HL activity (R = 0.48, -0.68, -0.56, respectively, p b 0.05). Significant correlations were also found between the reduction in TNFα and both the increase in ISI and increase in HL activity (R = -0.43, -0.54, respectively, P b 0.05). Conclusions: The association of the effect on post-prandial metabolism, plasma TNFα level and HL activity during prolonged enoxaparin treatment may support the hypothesis that the beneficial outcome of enoxaparin may possibly be linked to anti-inflammatory and lipase-potentiating impact.

BACKGROUND Premenopausal women have lower blood pressure (BP) levels than men of similar age. Adiponectin has been shown to play a role in the pathogenesis of hypertension. The aim of the present study was to compare the effect of various stress stimuli on BP and plasma adiponectin levels in male and female Sprague Dawley (SD) rats. METHODS In three experimental models of hypertension, fructose-enriched diet, high salt diet, or L-NAME, were administered for up to 4 weeks. BP, metabolic parameters, and plasma adiponectin were measured at baseline and during the studies. The fructose diet protocol was repeated in female rats for 2 weeks with the addition of testosterone injections or vehicle. RESULTS Females, in contrast to males, did not develop fructose-induced hypertension. Total plasma triglycerides (TGs) were half in females at baseline (P < 0.001) and a third at 4 weeks (P < 0.05). Plasma insulin levels were 23% lower in females than in males at baseline (P < 0.05) and 42% lower after 4 weeks of fructose-enriched diet (P = 0.001). Plasma adiponectin levels were 65% higher in females than in males at baseline (P = 0.001) and 45% higher after 4 weeks of fructose-enriched diet (P < 0.05). Furthermore, female rats showed blunted BP response and elevated plasma adiponectin in the salt-induced and L-NAME-induced hypertension models. Testosterone injection to female rats reduced plasma adiponectin and reversed the blunted BP response. CONCLUSIONS Elevated plasma adiponectin levels, perhaps due to lack of suppression by testosterone, are associated with a blunting of BP response in female compared to male SD rats.

Item does not contain fulltext BACKGROUND & AIMS: The identification of the cellular and molecular pathways that mediate the development of non-alcoholic steatohepatitis is of crucial importance. Cytokines produced by liver-resident and infiltrating inflammatory cells, play a pivotal role in liver inflammation. The role of the proinflammatory cytokines IL-1alpha and IL-1beta in steatohepatitis remains elusive. METHODS: We employed IL-1alpha and IL-1beta-deficient mice and transplanted marrow cells to study the role of liver-resident and bone marrow-derived IL-1 in steatosis and its progression to steatohepatitis. RESULTS: Atherogenic diet-induced steatohepatitis in wild-type mice was associated with 16 and 4.6 fold-elevations in mRNA levels of hepatic IL-1alpha and IL-1beta, respectively. In mice deficient in either IL-1alpha or IL-1beta the transformation of steatosis to steatohepatitis and liver fibrosis was markedly reduced. This protective effect in IL-1alpha-deficient mice was noted despite increased liver cholesterol levels. Deficiency of IL-1alpha markedly reduced plasma serum amyloid A and steady-state levels of mRNA coding for inflammatory genes (P-selectin, CXCL1, IL-6, and TNFalpha) as well as pro-fibrotic genes (MMP-9 and Collagen) and particularly a 50% decrease in TGFbeta levels (p = 0.004). IL-1alpha mRNA levels were two-folds lower in IL-1beta-deficient mice, and IL-1beta transcripts were three-folds lower in IL-1alpha-deficient compared to wild-type mice. Hepatic cell derived IL-1alpha rather than from recruited bone marrow-derived cells was required for steatohepatitis development. CONCLUSIONS: These data demonstrate the critical role of IL-1alpha and IL-1beta in the transformation of steatosis to steatohepatitis and liver fibrosis in hypercholesterolemic mice. Therefore, the potential of neutralizing IL-1alpha and/or IL-1beta to inhibit the development of steatohepatitis should be explored. 01 november 2011

Item does not contain fulltext OBJECTIVE: Interleukin (IL)-1alpha and IL-1beta are products of macrophages, endothelial cells and vascular smooth muscle cells; moreover, each of these cell types is affected by the pro-inflammatory properties of both IL-1's. Whereas several studies demonstrate the proatherogenic properties of IL-1beta, the role of IL-1alpha in atherogenesis remains unclear. We assessed whether IL-1alpha and IL-1beta from tissue resident vascular cells or emigrating bone marrow-derived cells promote the development of atherosclerosis in apoE-/- mice and determined the effect of selective macrophage IL-1alpha or IL-1beta deficiency on degradation of LDL and cytokine production. METHODS: We generated strains of double knock-out (KO) mice (apoE-/-/IL-1alpha-/- and apoE-/-/IL-1beta-/-) and created chimeras consisting of apoE-/- mice reconstituted with bone marrow-derived cells from apoE-/-/IL-1+/+, apoE-/-/IL-1alpha-/- and apoE-/-/IL-1beta-/-. RESULTS: The areas of aortic sinus lesions were lower in either double KO mice compared to solely apoE-/- mice, despite higher non-HDL cholesterol levels. Importantly, selective deficiency of IL-1alpha or IL-1beta in bone marrow-derived cells inhibited atherogenesis to the same extent as in double KO mice without affecting plasma lipids. Aortic sinus lesions in apoE-/- mice transplanted with IL-1beta-/- or IL-1alpha-/- cells were 32% and 52% lower, respectively, than in IL-1+/+ transplanted mice. Ex vivo, isolated IL-1alpha-/- macrophages from atherosclerotic mice degraded LDL and secreted IL-6, TNFalpha and IL-12 similarly to IL-1+/+ macrophages; however, IL-1alpha deficient macrophages secreted reduced levels of IL-1beta (-50%) and 2-3-fold higher levels of the anti-inflammatory cytokine IL-10. CONCLUSION: We show for the first time that it is IL-1alpha from bone marrow-derived cells that accelerates atherogenesis in apoE-deficient mice rather than constitutive IL-1alpha in vascular cells, possibly by increasing the inflammatory cytokine profile of macrophages.

BACKGROUND High sodium intake is associated with increased risk of end-organ damage, independent of blood pressure (BP) levels. The protective peptide adiponectin may play a role in the pathogenesis of hypertension and particularly in salt-loaded conditions. Furthermore, increased adiponectin levels were observed in salt-loaded conditions. However, there is little information on the direct effect of high-salt diet on plasma adiponectin. The aim of the present study was to examine the effect of high-salt diet on adiponectin levels in Sprague-Dawley rats and explore the mechanisms that regulate adiponectin levels under salt loading. METHODS Sprague-Dawley rats were fed either standard chow diet or medium or high sodium diet for 5 weeks. BP and plasma adiponectin were measured at baseline and during the study. In additional studies the same protocol was repeated with the addition of clonidine, telmisartan, hydralazine or eplerenone. RESULTS High-salt diet increased systolic BP, suppressed plasma aldosterone levels and attenuated body weight gain. Five weeks of salt loading increased plasma adiponectin levels in a dose-dependent manner (medium salt and high salt were 47 and 93% higher than control, respectively, P < 0.05). Hydralazine and clonidine attenuated salt-induced BP increase but did not attenuate the increase in adiponectin levels whereas, telmisartan, an angiotensin receptor blocker, and eplerenone, an aldosterone blocker, attenuated both the increase in BP and in adiponectin levels. CONCLUSIONS High salt intake increases adiponectin levels independent of the increase in BP. This effect is mediated through the renin-angiotensin-aldosterone system.

Our aim was to study the effect of 9-cis beta-carotene-rich powder of the alga Dunaliella bardawil on lipid profile, atherogenesis, and liver steatosis in high-fat diet-fed LDL receptor knockout mice. In 4 sets of experiments, mice were distributed into the following groups: control, fed an unfortified diet; Dunaliella 50, fed a diet composed of 50% 9-cis and 50% all-trans beta-carotene; Dunaliella 25, fed a diet containing 25% 9-cis and 75% all-trans beta-carotene; beta-carotene-deficient Dunaliella, fed beta-carotene-deficient Dunaliella powder; and all-trans beta-carotene, fed a synthetic all-trans beta-carotene. All fortified diets contained 0.6% total beta-carotene. Algal 9-cis beta-carotene was absorbed by the mice and accumulated in the liver. Synthetic all-trans beta-carotene was not converted to 9-cis beta-carotene. Dunaliella 50 inhibited high-fat diet-induced plasma cholesterol elevation by 40-63% and reduced cholesterol concentrations in the atherogenic VLDL and LDL. Atherosclerotic lesion area in mice treated with Dunaliella 50 was 60-83% lower compared with mice fed the high-fat diet alone. beta-Carotene-deficient Dunaliella did not influence plasma cholesterol and atherogenesis, suggesting that beta-carotene is essential for a Dunaliella protective effect. Moreover, by administrating Dunaliella powder containing different levels of 9-cis and all-trans beta-carotene isomers, we found that the effect on plasma cholesterol concentration and atherogenesis is 9-cis-dependent. Dunaliella 50 also inhibited fat accumulation and inflammation in the livers of mice fed a high-fat diet, which was accompanied by reduced mRNA levels of inflammatory genes. These results in mice suggest that 9-cis beta-carotene may have the potential to inhibit atherogenesis in humans.

Background The etiology of the metabolic syndrome (MS) includes both genetic and environmental factors. The two most commonly studied animal models of the MS are the high-sucrose diet given to spontaneously hypertensive rats (SHRs) and high-fructose diet given to Sprague Dawley rats (SDRs). This study compares between these two models. Methods The two rat strains were examined; within each group, the rats were assigned to either the high-sugar diet (SDRs with fructose-enriched diet and SHRs with sucrose-enriched diet) or standard rat chow (control group). The rats were followed for 7 weeks. The main MS components (obesity, hypertension, impaired glucose tolerance, hyperinsulinemia, hypertriglyceridemia, and hypercholesterolemia) were measured. Results At baseline systolic blood pressure (SBP), fasting blood levels of triglycerides and insulin, as well as glucose intolerance, were significantly higher among the SHRs compared to SDRs. Following fructose enrichment, SDRs became hyperinsulinemic, hypertriglyceridemic, hypercholesterolemic, hypertensive, and insulin resistant, whereas SHRs responded to sucrose supplementation by a significant elevation in blood pressure and mild worsening of insulin resistance. Endpoint results revealed superiority of sucrose--SHR model in terms of hypertension and superiority of fructose--SDR model in terms of hyperinsulinemia, hypertriglyceridemia, and hypercholesterolemia. Both models showed similar postintervention degree of glucose tolerance. Conclusions The fructose-fed SDR model represents a predominantly environmentally acquired MS, whereas the SHR model is less affected by dietary intervention and better displays the predominantly genetic spontaneous appearance of the syndrome. This fundamental difference should be taken into consideration when choosing an animal model to study the MS.

Atherosclerotic cardiovascular disease (CVD) is the universal leading cause of mortality and a major cause of morbidity. Additionally, the global epidemic of diabetes is associated with considerable cardiovascular mortality risk due to accelerated premature atherosclerosis. Development of effective therapies for atherosclerosis is dependent upon improved tools to assess atherosclerotic lesion progression in animal models. We present a novel technique that utilises scanning electron microscopy (SEM) for imaging wet biological specimens, thus enabling rapid and high-resolution imaging of atherosclerotic lesions. This wet SEM technique was used in an apoEdeficient mice model for morphological characterisation of early and advanced atherosclerotic lesions. Further demonstration of lipid-rich atherosclerotic lesions was carried out with osmium tetroxide staining for cholesterol. Gold immunolabelling of specific epitopes was applied in identification of the cellular and molecular components within the atherosclerotic lesions, namely foam cells, smooth muscle cells and collagen. The wet SEM technique demonstrates an accurate and detailed structural evaluation of the pathological process of atherosclerosis. Understanding the mechanisms that precipitate the atherosclerotic process, utilising this novel technique, may assist in the development of innovative therapeutic interventions for CVD management and prevention in the general population and in those with diabetes. Diabetes Vasc Dis Res 2008;5:44‐7 doi:10.3132/dvdr.2008.008