Reduced Lesion Area Research Articles

Low dose of the liver X receptor agonist, AZ876, reduces atherosclerosis in APOE*3Leiden mice without affecting liver or plasma triglyceride levels

Liver X receptor (LXR) agonists are atheroprotective but often induce hypertriglyceridaemia and liver steatosis. We investigated the effect of a novel high-affinity LXR activator, AZ876, on plasma lipids, inflammation and atherosclerosis, and compared the effects with another LXR agonist, GW3965. APOE*3Leiden mice were fed an atherogenic diet alone or supplemented with either AZ876 (5 or 20µmol·kg(-1) ·day(-1) ) or GW3965 (17µmol·kg(-1) ·day(-1) ) for 20 weeks. Total cholesterol and triglyceride levels were measured using commercial kits. Plasma cytokines were determined by using bead-based multiplex suspension array kits with the Luminex technology. Atherosclerosis was assessed histochemically and lesion composition was assessed by immunohistochemical methods. Low-dose AZ876 had no effect on plasma or liver lipids, whereas high-dose AZ876 increased plasma triglycerides (+110%) and reduced cholesterol (-16%) compared with controls. GW3965 increased plasma triglycerides (+70%). Low-dose AZ876 reduced lesion area (-47%); and high-dose AZ876 strongly decreased lesion area (-91%), lesion number (-59%) and severity. In either dose, AZ876 did not affect lesion composition. GW3965 reduced atherosclerosis and collagen content of lesions (-23%; P < 0.01). High-dose AZ876 and GW3965, but not low-dose AZ876, reduced inflammation as reflected by lower cytokine levels and vessel wall activation. We have identified a novel LXR agonist that when given in a low dose inhibits the progression of atherosclerosis without inducing anti-inflammatory effects, liver steatosis or hypertriglyceridaemia. Therefore, the primary protective action of a low-dose AZ876 is likely to be an increased reverse cholesterol transport.

Role for Nox1 NADPH oxidase in atherosclerosis

ObjectiveExamine the contribution of Nox1 NADPH oxidase to atherogenesis. Methods and resultsMale apolipoprotein E deficient mice (ApoE−/−) and male mice deficient in both apolipoprotein E and Nox1 (ApoE−/− Nox1−/y) received an atherogenic diet for 18 weeks. Mean blood pressures, body weights, and serum cholesterol levels were similar between the two groups of mice. Deficiency of Nox1 decreased superoxide levels and reduced lesion area in the aortic arch from 43% (ApoE−/−) to 28% (ApoE−/− Nox1−/y). The reduction in lesion size at the level of the aortic valve in ApoE−/−/Nox1−/y was accompanied by a decrease in macrophage infiltration as compared to ApoE−/− mice. Carotid artery ligation in ApoE−/− mice induced accelerated intimal hyperplasia with decreased cellular proliferation and increased collagen content in the neointima of vessels deficient in Nox1. ConclusionsNox1-derived ROS modify lesion composition and contribute to lesion size in a murine model of atherosclerosis.

Decompression of odontogenic cystic lesions: clinical long-term study of 73 cases

The aim of this study was to evaluate the effectiveness of decompression as the initial treatment for odontogenic cysts. Pre- and postdecompression panoramic radiographs of 57 patients treated for 73 odontogenic cysts were reviewed for reduction parameters. Findings were evaluated against time of decompression and clinical and histopathologic data. Decompression reduced lesion area by a mean of 79.3%. The reaction was good in 60% of cysts, moderate in 29%, and poor in 11%. Mean decompression time was 9.2 ± 5.2 months; it was 7.6 months in patients ≤18 years old and 10.2 months in older patients (P < .0001). Mean rate of reduction was 0.14 in cysts <10 cm(2) and 0.10 in cysts >20 cm(2) (P = .0884); by age, values were 0.14 in patients ≤18 years old and 0.09 in older patients (P < .05). Decompression is effective in reducing odontogenic cysts. A shorter decompression period is needed for young patients. For aggressive lesions, secondary definitive surgery is recommended.

Androgen Receptor-Dependent and Independent Atheroprotection by Testosterone in Male Mice

The atheroprotective effect of testosterone is thought to require aromatization of testosterone to estradiol, but no study has adequately addressed the role of the androgen receptor (AR), the major pathway for the physiological effects of testosterone. We used AR knockout (ARKO) mice on apolipoprotein E-deficient background to study the role of the AR in testosterone atheroprotection in male mice. Because ARKO mice are testosterone deficient, we sham operated or orchiectomized (Orx) the mice before puberty, and Orx mice were supplemented with placebo or a physiological testosterone dose. From 8 to 16 wk of age, the mice consumed a high-fat diet. In the aortic root, ARKO mice showed increased atherosclerotic lesion area (+80%, P < 0.05). Compared with placebo, testosterone reduced lesion area both in Orx wild-type (WT) mice (by 50%, P < 0.001) and ARKO mice (by 24%, P < 0.05). However, lesion area was larger in testosterone-supplemented ARKO compared with testosterone-supplemented WT mice (+57%, P < 0.05). In WT mice, testosterone reduced the presence of a necrotic core in the plaque (80% among placebo-treated vs. 12% among testosterone-treated mice; P < 0.05), whereas there was no significant effect in ARKO mice (P = 0.20). In conclusion, ARKO mice on apolipoprotein E-deficient background display accelerated atherosclerosis. Testosterone treatment reduced atherosclerosis in both WT and ARKO mice. However, the effect on lesion area and complexity was more pronounced in WT than in ARKO mice, and lesion area was larger in ARKO mice even after testosterone supplementation. These results are consistent with an AR-dependent as well as an AR-independent component of testosterone atheroprotection in male mice.

FAD286, an aldosterone synthase inhibitor, reduced atherosclerosis and inflammation in apolipoprotein E-deficient mice

Aldosterone is known to be involved in atherosclerosis and cardiovascular disease and blockade of its receptor was shown to improve cardiovascular function. It was, therefore, hypothesized that inhibition of aldosterone synthesis would also reduce atherosclerosis development. To test this hypothesis, we examined the effect of FAD286 (FAD), an aldosterone synthase inhibitor, on the development of atherosclerosis in spontaneous atherosclerotic apolipoprotein E-deficient mice. Mice were divided into three treatment groups: normal diet, low-salt diet (LSD) and LSD treated with FAD at 30 mg/kg per day (LSD + FAD) for 10 weeks. Histomorphometry of the aortas obtained from these mice showed that atherosclerotic lesion area increased by three-fold under LSD compared with normal diet and FAD significantly reduced lesion area to values similar to normal diet. Changes in atherosclerosis were paralleled by changes in the expression of the inflammation markers (C-reactive protein, monocyte chemotactic protein-1, interleukin-6, nuclear factor kappa B and intercellular adhesion molecule-1) in peritoneal macrophages obtained from these mice. Surprisingly, whereas LSD increased serum or urine aldosterone levels, FAD did not alter these levels when evaluated at the end of the study. In J774A.1 macrophage-like cell line stimulated with lipopolysaccharide, FAD was shown to have a direct dose-dependent anti-inflammatory effect. In apolipoprotein E-deficient mice, FAD reduces atherosclerosis and inflammation. However, these actions appeared to be dissociated from its effect on inhibition of aldosterone synthesis.

Abstract 4904: Comparative Anti-atherogenic Effects of a Single Intravenous Injection of rAAV8 Or rAAV2 Encoding Apo A-IMilano Gene

Background: We previously reported potent anti-atherogenic effects of gene transfer of Apo A-IMilano through transplant of retrovirally transduced bone marrow. In anticipation of potential evaluation of Apo A-IMilano gene transfer in human atherosclerosis, we evaluated the comparative anti- atherogenic efficacy of Apo A-IMilano gene transfer using intravenous injection of type-2 and type-8 recombinant adeno-associated viruses (rAAV2 and rAAV8) as vectors in Apo A-I/apo E null mice. Methods: Mice received one intravenous injection of 1.2×1012 vector genome copies of rAAV2 -Milano or rAAV2 -Control or rAAV8 -Milano or rAAV8 -Control (12 mice per group). Four weeks after injection mice were placed on high fat diet. Twenty weeks later mice were euthanized to analyze Apo A-IMilano gene expression and quantitative extent of aortic atherosclerosis after oil-red O staining. ELISA analysis of blood samples and real-time PCR analysis of target organs was used to determine the Apo A-IMilano gene expression. Blood was analyzed for cholesterol levels. Results: The circulating cholesterol levels were comparably elevated among the 4 groups. Serum Apo A-IMilano levels were significantly higher in rAAV8 -Milano injected mice compared to rAAV2 -Milano injected mice at 4 weeks (71 ± 31 ng/ml vs. 31 ± 21ng/ml) 12 weeks (92 ± 61 ng/ml vs. 30 ± 27), and at 24 weeks (45 ± 32 ng/ml vs. 7.6 ± 6 ng/ml) (P &lt;0.001 all groups). Real time PCR showed a significantly higher level of transgene expression in the heart (122 ± 36 fold), liver (32 ± 25 fold) and the brain (14 ± 0.39 fold) with rAAV8 -Milano compared to rAAV2 -Milano. Compared to rAAV8 -Control, the mean aortic lesion area was reduced by 42% by rAAV8 -Milano (7.7 ± 0.06% vs 13.4 ± 1.1 % of aorta; p = 0.001). Compared to rAAV2-Control, the mean aortic lesion area was reduced by 16% by rAAV2 -Milano (12.6 ± 0.8 vs 10.6 ± 0.8 % of aorta; p = NS). rAAV8 -Milano reduced lesion area by 27% compared to rAAV2 -Milano (p = 0.01). Conclusions: Intravenous rAAV8 -Milano results in higher in-vivo transgene expression and a significantly greater reduction in aortic atherosclerosis compared to vector control or rAAV2 -Milano.

Abstract 5200: Octyl-D-Carnosine Attenuates Atherogenesis in ApoE Null Mice Fed a Western Diet

Lipid endoperoxides resulting from oxidation of unsaturated lipids are further metabolized to reactive carbonyl species (RCS), which react with proteins to generate advanced lipoxidation endproducts (ALEs). ALEs are believed to evoke an inflammatory response which participates in all stages of atherosclerosis. The endogenous dipeptide L-carnosine was shown to act as quencher of RCS derived from lipoxidation. Since it is rapidly inactivated by carnosinase, we evaluated the effect of the carnosinase-resistant octyl ester of D-carnosine (ODC, Flamma SpA, 60 mg/kg in the drinking water) vs. vehicle on the development of atherosclerosis in female apoE null mice fed a western diet (42% fat) vs. standard chow for 12 weeks. Oil red O staining of en-face aorta preparations showed a significant reduction of lipid accumulation in ODC-treated vs. untreated ApoE null mice on western diet (13.2±2.5 vs. 19.2±2.0 %, P&lt;0.001). Morphometric evaluation of aortic lesions in sections stained with the Weigert-Van Gieson method showed significantly reduced lesion area in ODC-treated mice at the level of the aortic sinus and, particularly, of the brachiocephalic artery. ODC treatment also resulted in a more stable plaque phenotype, with less inflammation and apoptosis, and more collagen and VSMCs, resulting in reduced necrotic core formation (11.8±3.8 vs. 25.3±5.4%, P&lt;0.0001). The gene expression level of the markers of inflammation and lesion progression F4/80, MCP-1, VCAM –1, TNF- α , IFN- γ and matrix metalloproteinase-2 and 9 and the RCS- and ALE-receptors CD36, RAGE and gelectin-3 was significantly decreased and even normalized in western diet-fed ApoE null mice treated with ODC. These data indicate that generation of RCS and ALEs from lipid peroxidation plays a major role in atherogenesis and that quenching of these compounds with a D-carnosine ester may represent a promising approach to the prevention and treatment of vascular disease.

Effects of combination therapy with verteporfin photodynamic therapy and ranibizumab in patients with age-related macular degeneration

This open-label, prospective, small-scale study investigated the benefits of same-day verteporfin and intravitreal ranibizumab in patients with predominantly classic, minimally classic or occult subfoveal choroidal neovascularization (CNV) secondary to age-related macular degeneration. Patients received verteporfin at baseline and at month 3, if leakage persisted. Ranibizumab (0.5 mg) was given at baseline and months 1, 2 and 3, and thereafter at monthly intervals if required. Same-day ranibizumab was given ≥ 1 hr after verteporfin. Fifteen patients [11 male, four female; mean age 75.5 years (range 54-94 years)] were treated. At day 360, mean visual acuity (VA) had improved by 10.9 letters. An increase of ≥ 15 and ≥ 30 letters (i.e. ≥ 3 and ≥ 6 lines) was observed in seven (47%) patients and one patient (7%), respectively. Mean central retinal thickness (CRT) decreased by 85 μm. At days 7, 14 and 30, CNV perfusion was absent in 14/15 patients. Mean lesion area had reduced from baseline by 23.1% at day 120, 25.5% at day 180 and 23.6% at day 360. There were no visual safety concerns and intraocular pressures remained normal. Only two serious adverse events were recorded over the 12-month period, and neither was considered to be related to treatment. Same-day verteporfin plus ranibizumab improved VA, reduced CRT, prevented CNV perfusion and reduced lesion area safely over 12 months. Further investigation is warranted to confirm whether this combination improves long-term vision and reduces the need for retreatment.

Increased HDL Cholesterol and ApoA-I in Humans and Mice Treated With a Novel SR-BI Inhibitor

Increasing HDL levels is a potential strategy for the treatment of atherosclerosis. ITX5061, a molecule initially characterized as a p38 MAPK inhibitor, increased HDL-C levels by 20% in a human population of hypertriglyceridemic subjects with low HDL levels. ITX5061 also moderately increased apoA-I but did not affect VLDL/LDL cholesterol or plasma triglyceride concentrations. ITX5061 increased HDL-C in WT and human apoA-I transgenic mice, and kinetic experiments showed that ITX5061 decreased the fractional catabolic rate of HDL-CE and reduced its hepatic uptake. In transfected cells, ITX5061 inhibited SR-BI-dependent uptake of HDL-CE. Moreover, ITX5061 failed to increase HDL-C levels in SR-BI(-/-) mice. To assess effects on atherosclerosis, ITX5061 was given to atherogenic diet-fed Ldlr(+/-) mice with or without CETP expression for 18 weeks. In both the control and CETP-expressing groups, ITX5061-treated mice displayed reductions of early atherosclerotic lesions in the aortic arch -40%, P<0.05), and a nonsignificant trend to reduced lesion area in the proximal aorta. Our data indicate that ITX5061 increases HDL-C levels by inhibition of SR-BI activity. This suggests that pharmacological inhibition of SR-BI has the potential to raise HDL-C and apoA-I levels without adverse effects on VLDL/LDL cholesterol levels in humans.

Abstract: P482 NOVEL LXR AGONIST AZ876 REDUCES ATHEROSCLEROSIS WITHOUT INCREASING TRIGLYCERIDES IN PLASMA AND LIVER

P482 Citation: Atherosclerosis Supplement 2009, Vol. 10, Issue 2 NOVEL LXR AGONIST AZ876 REDUCES ATHEROSCLEROSIS WITHOUT INCREASING TRIGLYCERIDES IN PLASMA AND LIVER J van der Hoorn, D Linden, M Bekkers, M Voskuilen, U Lindahl, J Oscarsson, E Lindstedt, H Princen TNO BioSciences, Leiden; AstraZeneca, Molndal Objectives Liver X receptor (LXR) agonists are atheroprotective, but may induce hypertriglyceridemia and liver steatosis. We investigated the effect of the new LXR agonist AZ876 (AZ) on plasma lipids, inflammation and atherosclerosis. GW3965 (GW) was used as a reference. Methods APOE*3Leiden mice were fed an atherogenic diet alone or supplemented with either AZ (5 or 20 μmol/kg) or GW (17 μmol/kg). Effects on plasma parameters and atherosclerosis were assessed after 20 weeks of treatment. Results As compared to control, low dose AZ had no effect on plasma lipids, whereas the high dose AZ increased plasma triglycerides (+150%; p<0.001) and reduced cholesterol (-16%; p<0.05). GW increased plasma triglycerides (+70%; p<0.001). Low dose AZ reduced lesion area (-47%, p<0.05); and high dose AZ strongly decreased lesion area (-91%), the number of lesions (-59%) and lesion severity. In either dose AZ did not affect lesion composition. GW significantly reduced atherosclerosis, but also tended to decrease lesion stability. The atheroprotective effect by high dose AZ and GW were partly explained by their antiinflammatory effects. As low dose AZ did not reduce inflammation markers, the induction of reverse cholesterol transport may be its primary protective action. Signs of liver steatosis were not observed by treatment with low dose AZ or GW. Conclusions We identified a novel LXR agonist that inhibits the progression of atherosclerosis presumably by increasing reverse cholesterol transport rather than by decreasing inflammation, without inducing detrimental lipogenic effects in liver and hypertriglyceridemia. Funding: AstraZeneca provided a grant.

Rosuvastatin reduces atherosclerotic lesions and promotes progenitor cell mobilisation and recruitment in apolipoprotein E knockout mice

Statins enhance incorporation of bone marrow-derived cells into experimental neointimal lesions. However, the contribution of progenitor cells to progression of spontaneous atherosclerotic plaques, and the possible modulatory role of statins in this process, remain poorly understood. We compared the effects of rosuvastatin (1 and 10mg/kg BW) and pravastatin (10mg/kg) on progenitor cell mobilisation, recruitment into atherosclerotic plaques, and lesion growth. Statins were administered over 8 weeks to apolipoprotein E knockout mice on atherogenic diet. In addition, mice were lethally irradiated, followed by transplantation of bone marrow from LacZ transgenic mice. Rosuvastatin reduced lesion area and intima-to-media ratio at the brachiocephalic artery compared to vehicle, while both parameters were not significantly altered by pravastatin. Rosuvastatin also augmented endothelialisation (P<0.05) and reduced the smooth muscle cells (SMC) content (P=0.042) of lesions. Numbers of c-kit, sca-1 and flk-1, sca-1 double-positive progenitor cells were significantly increased in rosuvastatin compared to control-treated mice, both in the bone marrow and the peripheral blood. Similarly, the number of spleen-derived acLDL, lectin double-positive progenitor cells (P=0.001) and colony-forming units (P=0.0104) was significantly increased in mice treated with rosuvastatin compared to vehicle alone. In the bone marrow, increased Akt and p42/44 MAP kinase phosphorylation and upregulated SDF1α mRNA expression were observed. Importantly, rosuvastatin treatment also increased the plasma levels of c-kit ligand (P=0.003), and the number of c-kit-positive cells within atherosclerotic lesions (P=0.041). Our findings suggest that rosuvastatin reduces the size of atherosclerotic plaques, and this effect appears to involve progenitor cell mobilisation and recruitment into vascular lesions.

Inhibition of CETP activity by torcetrapib reduces susceptibility to diet-induced atherosclerosis in New Zealand White rabbits

Cholesteryl ester transfer protein (CETP) inhibitors increase high density lipoprotein-cholesterol (HDL-C) in animals and humans, but whether CETP inhibition will be antiatherogenic is still uncertain. We tested the CETP inhibitor torcetrapib in rabbits fed an atherogenic diet at a dose sufficient to increase HDL-C by at least 3-fold (207 +/- 32 vs. 57 +/- 6 mg/dl in controls at 16 weeks). CETP activity was inhibited by 70-80% throughout the study. Non-HDL-C increased in both groups, but there was no difference apparent by the study's end. At 16 weeks, aortic atherosclerosis was 60% lower in torcetrapib-treated animals (16.4 +/- 3.4% vs. 39.8 +/- 5.4% in controls) and aortic cholesterol content was reduced proportionally. Sera from a separate group of rabbits administered torcetrapib effluxed 48% more cholesterol from Fu5AH cells than did sera from control animals, possibly explaining the reduced aortic cholesterol content. Regression analyses indicated that lesion area in the torcetrapib-treated group was strongly correlated with the ratio of total plasma cholesterol to HDL-C but not with changes in other lipid or lipoprotein levels. CETP inhibition with torcetrapib retards atherosclerosis in rabbits, and the reduced lesion area is associated with increased levels of HDL-C.

Effect of an Alcohol-Free, 1% Chlorhexidine Gel as an Adjunct to a Fluoridated Dentifrice Using an Intraoral Crown Model

Background/Aims: The use of chlorhexidine as a topically applied oral antiseptic is well documented; however, clinical studies examining the effects of chlorhexidine gel on in situ dental caries are limited. This study utilized an in situ caries model and a modified crossover design to examine whether the addition of a biweekly topical, alcohol-free, 1% chlorhexidine digluconate gel to a daily fluoridated dentifrice inhibited artificial caries in dental tissues better than the fluoridated dentifrice alone when compared to a nonfluoridated placebo dentifrice. Methods: Thirty patients were recruited based on their need for a mandibular, full crown. Artificial caries lesions were created in extracted human teeth and enamel and root tissue sections 100 µm in thickness were characterized using polarized light microscopy. The sections were fixed in the crown and placed on the prepared tooth. The participants were assigned a placebo toothpaste, a toothpaste with 1,100 ppm F or a 1,100 ppm F toothpaste followed by 1 ml of 1% chlorhexidine gel at day 1 and day 14 (chlorhexidine+). Patients were instructed to brush twice daily for 4 weeks. Following each round, the sections in the crown were replaced with new sections. The sections were recharacterized and the mean changes were compared using ANOVA at α = 0.05. Results: The chlorhexidine + Fdentifrice and the F dentifrice alone significantly reduced lesion area in enamel tissue when compared to the placebo dentifrice. Both treatments also inhibited lesion progression and initiation in root tissue better than control in this model system. Although the chlorhexidine+ group enhanced remineralization and inhibited lesion progression better than the F^– dentifrice alone for all outcomes measured, the differences were not significant. Conclusions: The chlorhexidine, in conjunction with a fluoride dentifrice, was no more effective than the fluoride dentifrice alone. Further study is needed before this 1% alcohol-free chlorhexidine gel should be recommended as an adjunct to a fluoride dentifrice in the treatment of dental caries.

Increased atherosclerosis following treatment with a dual PPAR agonist in the ApoE knockout mouse

Objective Recent reports have suggested that dual peroxisome proliferator-activated receptor (PPAR) α/γ agonists are associated with adverse cardiovascular events. This study aimed to investigate the actions of the non-thiazolidinedione PPARα/γ agonist, compound 3q, on plaque development in the apolipoprotein E knockout (apoE KO) mouse, a recognised model of accelerated plaque development. Methods Six-week-old male apoE KO mice were randomised to receive the dual PPARα/γ agonist, compound 3q (3 mg/kg/day), the PPARγ agonist, rosiglitazone (20 mg/kg/day), the PPARα agonist, gemfibrozil (100 mg/kg/day) by gavage or no treatment for 20 weeks ( n = 12/group). Results Gemfibrozil and rosiglitazone significantly reduced lesion area. However, compound 3q was associated with a three-fold increase in total plaque area (versus control p < 0.001). This was associated with an upregulation of markers of plaque instability including vascular cell adhesion molecule-1 (3.5-fold, p < 0.001), P-selectin (3.4-fold, p < 0.001) monocyte chemoattractant protein-1 (3.4-fold; p < 0.001) as well as the scavenger receptor, CD36 (2-fold, p < 0.01). These disparate effects were observed with the dual PPAR agonist despite lowering LDL cholesterol and improving insulin sensitivity to a similar extent to PPARα and γ agonists used individually. Conclusion The finding of increased atherogenesis following a dual PPARα/γ agonist is consistent with recent clinical findings. These data provide an important framework for further exploring the potential utility and safety of combinatorial approaches.

Fenofibrate Reduces Atherogenesis in ApoE*3Leiden Mice

To demonstrate, quantify, and mechanistically dissect antiatherosclerotic effects of fenofibrate besides lowering plasma cholesterol per se. ApoE*3Leiden transgenic mice received either a high-cholesterol diet (HC) or HC containing fenofibrate (HC+FF) resulting in 52% plasma cholesterol-lowering. In a separate low-cholesterol diet (LC) control group, plasma cholesterol was adjusted to the level achieved in the HC+FF group. Low plasma cholesterol alone (assessed in LC) resulted in reduced atherosclerosis (lesion area, number and severity) and moderately decreased plasma serum amyloid-A (SAA) concentrations. Compared with LC, fenofibrate additively reduced lesion area, number and severity, and the total aortic plaque load. This additional effect in HC+FF was paralleled by an extra reduction of aortic inflammation (macrophage content; monocyte adhesion; intercellular adhesion molecule-1 [ICAM-1], soluble vascular cell adhesion molecule-1, granulocyte-macrophage colony-stimulating factor (GM-CSF), MCP-1, and NF-kappaB expression), systemic inflammation (plasma SAA and fibrinogen levels), and by an upregulation of plasma apoE levels. Also, enhanced expression of ABC-A1 and SR-B1 in aortic macrophages may contribute to the antiatherosclerotic effect of fenofibrate by promoting cholesterol efflux. Fenofibrate reduces atherosclerosis more than can be explained by lowering total plasma cholesterol per se. Impaired recruitment of monocytes/macrophages, reduced vascular and systemic inflammation, and stimulation of cholesterol efflux may all contribute to these beneficial effect of fenofibrate.

Clobetasol propionate 0·05% in a novel foam formulation is safe and effective in the short-term treatment of patients with delayed pressure urticaria: a randomized, double-blind, placebo-controlled trial

Delayed pressure urticaria (DPU) is characterized by the appearance of typical painful skin lesions (weals) after pressure stimulus. Oral corticosteroids are effective treatments but long-term therapy is problematic. A new topical formulation of clobetasol propionate 0.05% in thermophobic foam (CF) (Olux) has recently become available. The foam is easy to apply, with low skin residues. To evaluate in a double-blind placebo-controlled trial the efficacy, tolerability and safety of CF in the topical treatment of DPU. Twenty-six subjects with a positive history of DPU (13 men, mean age 44 years) were enrolled in a 4-week trial. CF or the corresponding placebo were applied twice daily. Drug application was performed in the most affected areas and in a target area where a standardized pressure challenge test was performed at baseline and at week 4. Efficacy was evaluated by scoring skin lesions regarding erythema, oedema and itching (0, no sign; 4, severe signs) and by calculating the area of the pressure challenge-induced lesion. Safety was evaluated by measuring plasma levels of adrenocorticotropic hormone (ACTH) and cortisol. CF significantly (P = 0.0001) reduced lesion area by 84% in comparison with baseline values and by 97% in comparison with the placebo group values. Lesion area in the CF group was reduced from 144 cm(2) to 21 cm(2) at the end of the study. No significant differences in lesion area and clinical lesion scores were observed in the placebo group (lesion area 201 cm(2) at baseline; 216 cm(2) after 4 weeks). A significant clinical improvement was observed in all treated skin areas in the CF group. Mean +/- SD erythema score was reduced by CF from 1.8 +/- 0.6 at baseline to 0.6 +/- 0.5 at the end of the treatment (P = 0.001). Similar modifications were observed also for oedema (from 1.6 +/- 0.6 to 0.2 +/- 0.5) and itching score. Nonsignificant modifications of plasma levels of ACTH, cortisol and glucose were observed in both study groups, in comparison with baseline values. No adverse events were recorded during the trial in either treatment group. CF is effective, safe, convenient and well tolerated in the short-term treatment of DPU.

Differential effects of angiotensin II on atherogenesis at the aortic sinus and descending aorta of apolipoprotein-E-deficient mice

Angiotensin (Ang) II infusion increases atherosclerosis and leads to the formation of abdominal aortic aneurysms in apolipoprotein E-deficient (ApoE-/-) mice. Conversely, blockade of the renin-angiotensin system (RAS) decreases atherosclerosis in this model. However, there are conflicting data in the literature concerning responses to both Ang II infusion and RAS blockade which may depend on age, sex, dose, duration of treatment, and the site at which lesion area was measured. In the present study we examined the effects of Ang II infusion on lesion formation in male ApoE-/- mice both at the aortic sinus and in the descending aorta, starting at different ages, and varying in duration. We also tested the effects of the Ang II receptor antagonist losartan at different doses in both males and females. Blood pressure and plasma renin concentration (PRC) were measured as indicators of the hemodynamic and neurohormonal effects of these treatments. Administration of Ang II increased lesion area much more in the descending aorta than at the aortic sinus. However, spontaneous lesion development at the aortic sinus was much greater than in more distal regions of the aorta. Aneurysms were observed in all treatment groups but were less severe in animals treated from 4 weeks age, possibly because of protective remodeling. Losartan treatment reduced lesion area at the aortic sinus, although differences were only significant in female mice. These findings demonstrate regional and temporal differences in the sensitivity of the aorta to the effects of RAS stimulation and blockade, and may help to explain some of the discrepancies between previous reports from other laboratories.

Dietary Antioxidants Decrease Serum Soluble Adhesion Molecule (sVCAM‐1, sICAM‐1) but not Chemokine (JE/MCP‐1, KC) Concentrations, and Reduce Atherosclerosis in C57BL but Not ApoE*3 Leiden Mice Fed an Atherogenic Diet

Dietary antioxidants are reported to suppress cellular expression of chemokines and adhesion molecules that recruit monocytes to the artery wall during atherosclerosis. In the present study we measured the effect of feeding apoE*3 Leiden mice or their non-transgenic (C57BL) littermates with atherogenic diets either deficient in, or supplemented with, dietary antioxidants (vitamin E, vitamin C and β-carotene) for 12 weeks, on serum levels of CC (JE/MCP-1) and CXC (KC) chemokines and soluble adhesion molecules (sVCAM-1, sICAM-1) and atherosclerotic lesion size. ApoE*3 Leiden mice developed gross hypercholesterolaemia, and markedly accelerated (10–20 fold; P < 0.0001) atherogenesis, compared with non-transgenic animals. Antioxidant consumption reduced lesion area in non-transgenic, but not apoE*3 Leiden, mice. Serum sVCAM-1 and sICAM-1 levels were significantly (P < 0.0001) increased (sVCAM-1 up to 3.9 fold; sICAM-1 up to 2.4 fold) by 4—8 weeks in all groups, and then declined. The initial increase in the concentration of adhesion molecules was reduced by 38%— 61% (P < 0.05) by antioxidant consumption, particularly in non-transgenic mice. By contrast, serum chemokine levels tended to increase more rapidly from baseline in apoE*3 Leiden mice, compared with non-transgenic animals, but were unaffected by dietary antioxidants. We conclude that dietary antioxidants reduce circulating soluble adhesion molecules and atherosclerosis in C57BL mice.

17β-Estradiol extends ischemic thresholds and exerts neuroprotective effects in cerebral subcortex against transient focal cerebral ischemia in rats

Neuroprotective effects of estrogens are demonstrated consistently in the cerebral cortex, but not in subcortical areas. In the present study, transient middle cerebral artery occlusions (MCAO) were induced for various duration, and protective effects of estrogen treatment on the cerebral cortex and subcortex were evaluated. MCAO was induced for 30, 40 or 60 min in ovariectomized rats. Animals were treated with 17β-estradiol (E2) or vehicle (OVX) 2 h before MCAO and sacrificed 24 h after the indicated duration of MCAO. Ischemic lesion was evaluated by 2,3,5-triphenyltetrazolium chloride staining, hematoxylin and eosin staining, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. E2 treatment reduced the magnitude and delayed the appearance of the total ischemic lesion area and largely prevented TUNEL staining in the cortex. In the subcortex, E2 treatment prevented the ischemic lesion in the 30-min group, reduced lesion area in the 40-min group, but had no effect on ischemic lesion area in the 60-min group. E2 treatment significantly decreased apoptotic cell number in the subcortical area at 30 and 40 min, but not at 60 min of MCAO. This study demonstrated that estrogen treatment can protect the cerebral subcortex in a severity-dependent manner, suggesting that the lack of protective effects of estrogen treatment in the subcortex is not due to the lack of estrogen receptors. Further, this study indicates that estrogens could be used as a neuroprotectant to prolong the therapeutic window of thrombolysis and prolong the time of cerebral circulation intervention for neurosurgical procedure.

Evaluation of microorganisms for biocontrol of grey mould on lettuce

A range of microorganisms including saprophytic yeasts bacteria and fungi were evaluated for control of Botrytis grey mould on whole lettuce plants In a controlled environment (1822C 8590 relative humidity and 12 h photoperiod) lettuce leaves were spray inoculated with antagonists (107 fungal spores/cells/ml or 108 bacterial cells/ml) allowed to dry and challenged by spray inoculation with the pathogen (106 spores/ml) After 7 days the mean Botrytis lesion areas were assessed Four fluorescent Pseudomonas spp (isolates LC8 PF13 PF14 and PF15) significantly reduced lesion areas by an average of 79 on whole lettuce plants in two experiments An Ulocladium sp (U13) significantly reduced lesion areas by 94 in one of two experiments