Skin morphology in double apoA-I/apoE knock-out mice: a structural and ultrastructural study

Apolipoprotein(apo)A-I, the main protein component of high density lipoproteins (HDLs), plays a major role in cholesterol removal from peripheral tissues and increasing evidence supports its function as an important regulator of the immune response (Annema et al., 2013). The aim of the study was to evaluate the effect of apoA-I deficiency in dyslipidemic mice, when fed a low-fat/low-cholesterol diet. Three lines of male mice were considered: wild-type mice as controls, apoE-KO mice as dyslipidemic model (Zhang et al.,1992) and apoA-I/apoE double KO mice (DKO mice). Whereas in wild-type mice cholesterol circulates almost exclusively in HDLs, apoE-KO mice are hypercholesterolemic and cholesterol mostly circulates in low-density lipoproteins. In DKO mice, cholesterol levels are comparable to wild-type mice, but HDLs are almost absent and cholesterol entirely accumulates in low-density lipoproteins. In the present study, all animals were maintained on a low-fat/low-cholesterol diet up to 30 weeks of age. At sacrifice, skin biopsies from two different anatomical areas (thoracic and abdominal regions) were harvested from each animal and processed for both light (LM) and transmission electron microscopy (TEM). Whereas the skin of apoE-KO mice was comparable to that of control mice, LM analysis in DKO mice revealed an increase in dermal thickness and a massive presence of foam cells and lymphocytes. TEM analysis showed the presence of cholesterol clefts in the papillary dermis and inside foam cells in the reticular dermis. In conclusion, our results demonstrate that in DKO mice fed a low-fat/low-cholesterol diet, the lack of apoA-I is responsible for an aberrant skin morphology, with an exacerbated inflammatory response, possibly caused by a local cholesterol accumulation

A salmon protein hydrolysate exerts lipid-independent anti-atherosclerotic activity in apoE-deficient mice

Fish consumption is considered health beneficial as it decreases cardiovascular disease (CVD)-risk through effects on plasma lipids and inflammation. We investigated a salmon protein hydrolysate (SPH) that is hypothesized to influence lipid metabolism and to have anti-atherosclerotic and anti-inflammatory properties. 24 female apolipoprotein (apo) E−/− mice were divided into two groups and fed a high-fat diet with or without 5% (w/w) SPH for 12 weeks. The atherosclerotic plaque area in aortic sinus and arch, plasma lipid profile, fatty acid composition, hepatic enzyme activities and gene expression were determined. A significantly reduced atherosclerotic plaque area in the aortic arch and aortic sinus was found in the 12 apoE−/− mice fed 5% SPH for 12 weeks compared to the 12 casein-fed control mice. Immunohistochemical characterization of atherosclerotic lesions in aortic sinus displayed no differences in plaque composition between mice fed SPH compared to controls. However, reduced mRNA level of Icam1 in the aortic arch was found. The plasma content of arachidonic acid (C20:4n-6) and oleic acid (C18:1n-9) were increased and decreased, respectively. SPH-feeding decreased the plasma concentration of IL-1β, IL-6, TNF-α and GM-CSF, whereas plasma cholesterol and triacylglycerols (TAG) were unchanged, accompanied by unchanged mitochondrial fatty acid oxidation and acyl-CoA:cholesterol acyltransferase (ACAT)-activity. These data show that a 5% (w/w) SPH diet reduces atherosclerosis in apoE−/− mice and attenuate risk factors related to atherosclerotic disorders by acting both at vascular and systemic levels, and not directly related to changes in plasma lipids or fatty acids

Association of alpha tocopherol and ag sulfadiazine chitosan oleate nanocarriers in bioactive dressings supporting platelet lysate application to skin wounds

Chitosan oleate was previously proposed to encapsulate in nanocarriers some poorly soluble molecules aimed to wound therapy, such as the anti-infective silver sulfadiazine, and the antioxidant α tocopherol. Because nanocarriers need a suitable formulation to be administered to wounds, in the present paper, these previously developed nanocarriers were loaded into freeze dried dressings based on chitosan glutamate. These were proposed as bioactive dressings aimed to support the application to wounds of platelet lysate, a hemoderivative rich in growth factors. The dressings were characterized for hydration capacity, morphological aspect, and rheological and mechanical behavior. Although chitosan oleate nanocarriers clearly decreased the mechanical properties of dressings, these remained compatible with handling and application to wounds. Preliminary studies in vitro on fibroblast cell cultures demonstrated good compatibility of platelet lysate with nanocarriers and bioactive dressings. An in vivo study on a murine wound model showed an accelerating wound healing effect for the bioactive dressing and its suitability as support of the platelet lysate application to wounds

Myocardial overexpression of ANKRD1 causes sinus venosus defects and progressive diastolic dysfunction

Increased ANKRD1 levels linked to gain of function mutations have been associated to total anomalous pulmonary venous return and adult cardiomyopathy occurrence in humans. The link between increased ANKRD1 level and cardiac structural and functional disease is not understood. To get insight into this problem, we have generated a gain of function ANKRD1 mouse model by overexpressing ANKRD1 in the myocardium

Hepatic paramters in apoE^-/- mice fed a high-fat diet (control) or a diet supplemented with 0.3% TTA for 12 weeks.

<p>In liver extracts, fatty acids were measured using gas-liquid chromotography, enzyme activities were measured spectrophotometrically and lipid deposition was assessed using Red Oil staining. <b>A</b>) Tetradecylthioacetic aicd and <b>B</b>) TTA:1n-8, <b>C</b>) Carnitine palmitoyltransferase 1a activity, <b>D</b>) carnitine palmitoyltransferase 2 <b>E</b>) 3-hydroxy-3-methylglutaryl coenzyme A synthase activity <b>F</b>) Citrate synthase activity, <b>G</b>) Acyl-coenzyme A oxidase activity, <b>H</b>) Lipids droplets and <b>I</b>) Triacylglycerols. Bars represent means ± SD in 4-6 mice for each diet. Unpaired <i>t</i>-test was used to detect statistical significance and results significantly different from control are indicated *P<0.05, **P<0.01, ***P<0.001.</p

Plasma lipid concentrations of apoE^-/- mice fed a high-fat diet (control) or a diet supplemented with 0.3% TTA.

<p>After 28, 56 and 77 days of diet induction, blood was collected, EDTA plasma was isolated and plasma lipids were determined by enzymatic assay. <b>A</b>) Triacylglycerols, <b>B</b>) Non-esterified fatty acids, <b>C</b>) Cholesterol, <b>D</b>) Free cholesterol, <b>E</b>) High-density lipoprotein cholesterol and <b>F</b>) Low-density lipoprotein cholesterol. Bars represent means ± SD for 4 mice for each diet. Unpaired <i>t</i>-test was used to detect statistical significance and results significantly different from control are indicated *P<0.05, **P<0.01, ***P<0.001.</p

Plasma fatty acid composition in apoE^−/− mice fed a high-fat casein diet (control) or a high-fat diet with 5% SPH after 77 days of dietary treatment.

1<p>Fatty acids (% w/w).</p><p>Data are shown as mean ± SD (<i>n</i> = 4).</p><p>Abbreviations: MUFAs, monounsaturated fatty acids; PUFAs, polyunsaturated fatty acids; SFAs, saturated fatty acids; SPH, salmon protein hydrolysate.</p><p>*P<0.05 vs. control.</p><p>**P<0.01 vs. control.</p><p>***P<0.001 vs. control.</p

Levels of mRNA expression in aorta and inflammatory mediators in plasma in apoE^−/− mice fed a high-fat diet (control) or a diet with 5% SPH for 12 weeks.

<p>(A) The gene expressions of the inflammatory markers <i>Icam1</i>, <i>Vcam1</i>, <i>Nos2</i> and <i>Mcp1</i> were measured in pooled aortic arch from six mice. Inflammatory markers in blood samples collected at day 77 of treatment were analysed (B) IL-1β, (C) IL-6, (D) IL-10, (E) TNF-α, (F) GM-CSF and bars represent means ± SD of 4 pooled samples of 3 mice for each diet. Unpaired <i>t</i>-test was used to assess statistical significance and results significantly different from control are indicated (*P<0.05, **P<0.01).</p

Histological and immunohistochemical characterization of plaques in the aortic sinus in apoE^−/− mice fed a high-fat diet (control) or a diet with 5% SPH for 12 weeks.

<p>Representative photomicrographs and quantification of maximum plaque area (panels A–C). Representative photomicrographs and quantification of extracellular matrix deposition (panels D–F), Lipid deposition (panels G–I), Macrophages (panels J–L) and T lymphocytes (panels M–O). The amount of extracellular matrix, lipids, macrophages and T-lymphocytes is expressed as percentage of the stained area over the total plaque area. Bar in panel A = 100 µm. Positive area (%) refers to the percentage of the plaque area occupied by connective tissue, lipids, macrophages and T lymphocytes, respectively. Data are shown as means ± SD for 6 mice for each diet and unpaired <i>t</i>-test was used to detect significance (*P<0.05).</p

Relative mRNA levels of inflammatory and oxidative stress markers in heart of apoE^-/- mice fed a high-fat diet (control) or a diet supplemented with 0.3% TTA after 12 weeks.

<p><b>A</b>) Nos2, <b>B</b>) Catalase, <b>C</b>) <i>Icam1</i>, <b>D</b>) <i>Vcam1</i> and <b>E</b>) Aortic arch. Bars represent means ± SD for 3-4 mice for each diet. Mann-Whitney test was used to detect statistical significance and results significantly different from control are indicated **P<0.01. </p