The resolvin D2 - GPR18 axis is expressed in human coronary atherosclerosis and transduces atheroprotection in apolipoprotein E deficient mice.

Chronic inflammation in atherosclerosis reflects a failure in the resolution of inflammation. Pro-resolving lipid mediators derived from omega-3 fatty acids reduce the development of atherosclerosis in murine models. The aim of the present study was to decipher the role of the specialized proresolving mediator (SPM) resolvin D2 (RvD2) in atherosclerosis and its signaling through the G-protein coupled receptor (GPR) 18. The ligand and receptor were detected in human coronary arteries in relation to the presence of atherosclerotic lesions and its cellular components. Importantly, RvD2 levels were significantly higher in atherosclerotic compared with healthy human coronary arteries. Furthermore, apolipoprotein E (ApoE) deficient hyperlipidemic mice were treated with either RvD2 or vehicle in the absence and presence of the GPR18 antagonist O-1918. RvD2 significantly reduced atherosclerosis, necrotic core area, and pro-inflammatory macrophage marker expression. RvD2 in addition enhanced macrophage phagocytosis. The beneficial effects of RvD2 were not observed in the presence of O-1918. Taken together, these results provide evidence of atheroprotective pro-resolving signalling through the RvD2-GPR18 axis.

Artesunate attenuates atherosclerosis by inhibiting macrophage M1-like polarization and improving metabolism.

OBJECT: Atherosclerosis (AS) is caused by chronic inflammation. Artesunate (ART), a sesquiterpene lactone endoperoxide isolated from Chinese herbal medicine, displays excellent anti-inflammatory activity. In this study, we investigated the effects of artesunate on atherosclerosis in ApoE knock-out mice, and used untargeted metabolomics to determine metabolite changes in these mice following ART treatment. METHODS: ApoE knock-out mice were fed a western diet and administered ART for eight weeks. Untargeted metabolomics was used to detect differential metabolites following the administration of ART. Oil Red O was used to assess plaque size, western blot and ELISA were used to detect inflammatory factors, and flow cytometry was used to detect the expression of markers on macrophages. RESULTS: Results of the in vivo experiment suggested that ART reduced atherosclerotic plaques in murine aortic root. In addition both in vivo and vitro experiments suggested that ART reduced the expression levels of inflammating cytokines, but enhanced those of the anti-inflammatory cytokines in macrophages. Untargeted metabolomic analysis demonstrated that multiple metabolic pathways, which were blocked in AS mice, showed different degrees of improvement following ART treatment. Furthermore, bioinformatic analyses showed that the HIF-1α pathway was altered in the AS mice and the ART treatment mice. In vitro experiments confirmed that LPS-induced upregulation of HIF-1α expression and activation of the NF-κB signaling pathways was significantly inhibited by ART treatment. CONCLUSION: These results suggest that ART exerts anti-atherosclerosis effects by inhibiting M1 macrophage polarization. One of the molecular mechanisms is that ART inhibits M1-like macrophage polarization via regulating HIF-1α and NF-κB signaling pathways.

Consumption of Non-Nutritive Sweetener, Acesulfame Potassium Exacerbates Atherosclerosis through Dysregulation of Lipid Metabolism in ApoE-/- Mice.

Obesity is associated with the risk of cardiovascular disease, and non-nutritive sweetener, such as acesulfame potassium (AceK) has been used to combat obesity. However, the effects of AceK on cardiovascular disease are still unclear. In this study, high cholesterol diet (HCD)-fed ApoE-/- mice had dysregulated plasma lipid profile, and developed atherosclerosis, determined by atherosclerotic plaque in the aorta. Supplement of AceK in HCD worsened the dyslipidemia and increased atherosclerotic plaque, as compared with HCD-fed ApoE-/- mice. Since treatment of AceK in RAW264.7 macrophages showed no significant effects on inflammatory cytokine expressions, we then investigated the impacts of AceK on lipid metabolism. We found that AceK consumption enhanced hepatic lipogenesis and decreased ß-oxidation in ApoE-/- mice. In addition, AceK directly increased lipogenesis and decreased ß-oxidation in HepG2 cells. Taken together, a concurrent consumption of AceK exacerbated HCD-induced dyslipidemia and atherosclerotic lesion in ApoE-/- mice, and AceK might increase the risk of atherosclerosis under HCD.

Beneficial effects of inorganic nitrate in non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) is considered the hepatic representation of the metabolic disorders. Inorganic nitrate/nitrite can be converted to nitric oxide, regulate glucose metabolism, lower lipid levels, and reduce inflammation, thus raising the hypothesis that inorganic nitrate/nitrite could be beneficial for improving NAFLD. This study assessed the therapeutic effects of chronic dietary nitrate on NAFLD in a mouse model. 60 ApoE-/- mice were fed a high-fat diet (HFD) for 12 weeks to allow for the development of atherosclerosis with associated NAFLD. The mice were then randomly assigned to different groups (20/group) for a further 12 weeks: (i) HFD + NaCl (1 mmol/kg/day), (ii) HFD + NaNO3 (1 mmol/kg/day), and (iii) HFD + NaNO3 (10 mmol/kg/day). A fourth group of ApoE-/- mice consumed a normal chow diet for the duration of the study. At the end of the treatment, caecum contents, serum, and liver were collected. Consumption of the HFD resulted in significantly greater lipid accumulation in the liver compared to mice on the normal chow diet. Mice whose HFD was supplemented with dietary nitrate for the second half of the study, showed an attenuation in hepatic lipid accumulation. This was also associated with an increase in hepatic AMPK activity compared to mice on the HFD. In addition, a significant difference in bile acid profile was detected between mice on the HFD and those receiving the high dose nitrate supplemented HFD. In conclusion, dietary nitrate attenuates the progression of liver steatosis in ApoE-/- mice fed a HFD.

Long-term administration of low-dose selenium nanoparticles with different sizes aggravated atherosclerotic lesions and exhibited toxicity in apolipoprotein E-deficient mice.

Exploration of long-term in vivo effects of nanomaterials, particularly those with potential biomedical applications, is quite important for better understanding and evaluating their biosafety. Selenium nanoparticles (SeNPs) has been considered as a good candidate in biomedical applications due to its high bioavailability, considerable biological activity, and low toxicity. However, its long-term biological effects and biosafety remain unknown. Our previous study demonstrated that 8-week supplementation with SeNPs (50 µg Se/kg/day) was safe and had an anti-atherosclerotic activity in apolipoprotein E-deficient (ApoE-/-) mice, a well-known animal model of atherosclerosis. As a chronic disease, atherosclerosis needs long-term drug therapy. The aim of this study is to investigate the long-term effects of SeNPs with different sizes on atherosclerotic lesions and their biosafety in ApoE-/- mice fed with a high fat diet. Unexpectedly, the results showed that 24-week administration of SeNPs even at a low dose (50 µg Se/kg/day) aggravated atherosclerotic lesions. Furthermore, SeNPs exacerbated oxidative stress by inhibiting the activities of antioxidant enzymes and the expression of antioxidant selenoenzymes. SeNPs also exacerbated hyperlipidaemia by inducing hepatic lipid metabolic disorder. In the meanwhile, SeNPs aggravated organ injury, especially liver and kidney injury. The above adverse effects of SeNPs were size dependent: SeNPs with the size of 40.4 nm showed the highest adverse effects among the SeNPs with three sizes (23.1 nm, 40.4 nm, and 86.8 nm). In conclusion, the present work shows that long-term administration of low-dose SeNPs aggravated atherosclerotic lesions by enhancing oxidative stress and hyperlipidaemia in ApoE-/- mice, indicative of cardiovascular toxicity. Moreover, long-term administration of SeNPs led to injury to liver and kidney. These results offer novel insights for better understanding the biosafety of SeNPs and other biomedical nanomaterials.

The benzoate plant metabolite ethyl gallate prevents cellular- and vascular-lipid accumulation in experimental models of atherosclerosis.

Ethyl gallate (EG) is a well-known constituent of medicinal plants, but its effects on atherosclerosis development are not clear. In the present study, the anti-atherosclerosis effects of EG and the underlying mechanisms were explored using macrophage cultures, zebrafish and apolipoprotein (apo) E deficient mice. Treatment of macrophages with EG (20 µM) enhanced cellular cholesterol efflux to HDL, and reduced net lipid accumulation in response to oxidized LDL. Secretion of monocyte chemotactic protein-1 (MCP-1) and interleukin-6 (IL-6) from activated macrophages was also blunted by EG. Fluorescence imaging techniques revealed EG feeding of zebrafish reduced vascular lipid accumulation and inflammatory responses in vivo. Similar results were obtained in apoE-/- mice 6.5 months of age, where plaque lesions and monocyte infiltration into the artery wall were reduced by 70% and 42%, respectively, after just 6 weeks of injections with EG (20 mg/kg). HDL-cholesterol increased 2-fold, serum cholesterol efflux capacity increased by ∼30%, and the levels of MCP-1 and IL-6 were reduced with EG treatment of mice. These results suggest EG impedes early atherosclerosis development by reducing the lipid and macrophage-content of plaque. Underlying mechanisms appeared to involve HDL cholesterol efflux mechanisms and suppression of pro-inflammatory cytokine secretion.

Carrot Supplementation Improves Blood Pressure and Reduces Aortic Root Lesions in an Atherosclerosis-Prone Genetic Mouse Model.

Epidemiological studies have shown that carrot consumption may be associated with a lower risk of developing several metabolic dysfunctions. Our group previously determined that the Bolero (Bo) carrot variety exhibited vascular and hepatic tropism using cellular models of cardiometabolic diseases. The present study evaluated the potential metabolic and cardiovascular protective effect of Bo, grown under two conditions (standard and biotic stress conditions (BoBS)), in apolipoprotein E-knockout (ApoE-/-) mice fed with high fat diet (HFD). Effects on metabolic/hemodynamic parameters and on atherosclerotic lesions have been assessed. Both Bo and BoBS decreased plasma triglyceride and expression levels of genes implicated in hepatic de novo lipogenesis and lipid oxidation. BoBS supplementation decreased body weight gain, secretion of very-low-density lipoprotein, and increased cecal propionate content. Interestingly, Bo and BoBS supplementation improved hemodynamic parameters by decreasing systolic, diastolic, and mean blood pressure. Moreover, Bo improved cardiac output. Finally, Bo and BoBS substantially reduced the aortic root lesion area. These results showed that Bo and BoBS enriched diets corrected most of the metabolic and cardiovascular disorders in an atherosclerosis-prone genetic mouse model and may therefore represent an interesting nutritional approach for the prevention of cardiovascular diseases.

Selenium nanoparticles inhibit the formation of atherosclerosis in apolipoprotein E deficient mice by alleviating hyperlipidemia and oxidative stress.

Atherosclerosis can cause severe cardiovascular diseases, which is the most common cause of death in the world. It's of great significance to study the prevention and treatment of atherosclerosis. Selenium nanoparticles (SeNPs) has drawn more and more attention due to high biological activity, high bioavailability, strong antioxidant capacity and low toxicity, exhibiting great potential in biomedical application. Thus, this study aimed at explore the anti-atherosclerotic effect of two kinds of SeNPs, bovine serum albumin (BSA) surface-decorated SeNPs and chitosan (CS) surface-decorated SeNPs (CS-SeNPs), in apolipoprotein E deficient (ApoE-/-) mice fed with a high-cholesterol and high-fat diet, and the possible mechanisms. The results demonstrated that both BSA-SeNPs (25, 50 and 100 µg Se/kg body weight/day) and CS-SeNPs (50 µg Se/kg body weight/day) could reduce atherosclerotic lesions in ApoE-/- mice after oral administration for 12 weeks. And these effects might mainly attributed to the ability of BSA-SeNPs and CS-SeNPs to inhibit hyperlipidemia by suppressing hepatic cholesterol and fatty acid metabolism, and alleviate oxidative stress by enhancing antioxidant activity. Moreover, the benefits of BSA-SeNPs were dose-dependent and the medium dose of BSA-SeNPs (50 µg Se/kg body weight/day) was optimal. Generally, BSA-SeNPs with mean size 38.5 nm and negative surface charge showed better anti-atherosclerotic effect than CS-SeNPs with mean size 65.8 nm and positive surface charge. These results suggested that SeNPs could significantly alleviate the formation of atherosclerosis in ApoE-/- mice, possibly by inhibiting hyperlipidemia and oxidative stress, exhibiting a potential to serve as an anti-atherosclerotic agent.

Studies of ApoD-/- and ApoD-/-ApoE-/- mice uncover the APOD significance for retinal metabolism, function, and status of chorioretinal blood vessels.

Apolipoprotein D (APOD) is an atypical apolipoprotein with unknown significance for retinal structure and function. Conversely, apolipoprotein E (APOE) is a typical apolipoprotein with established roles in retinal cholesterol transport. Herein, we immunolocalized APOD to the photoreceptor inner segments and conducted ophthalmic characterizations of ApoD-/- and ApoD-/-ApoE-/- mice. ApoD-/- mice had normal levels of retinal sterols but changes in the chorioretinal blood vessels and impaired retinal function. The whole-body glucose disposal was impaired in this genotype but the retinal glucose metabolism was unchanged. ApoD-/-ApoE-/- mice had altered sterol profile in the retina but apparently normal chorioretinal vasculature and function. The whole-body glucose disposal and retinal glucose utilization were enhanced in this genotype. OB-Rb, both leptin and APOD receptor, was found to be expressed in the photoreceptor inner segments and was at increased abundance in the ApoD-/- and ApoD-/-ApoE-/- retinas. Retinal levels of Glut4 and Cd36, the glucose transporter and scavenger receptor, respectively, were increased as well, thus linking APOD to retinal glucose and fatty acid metabolism and suggesting the APOD-OB-Rb-GLUT4/CD36 axis. In vivo isotopic labeling, transmission electron microscopy, and retinal proteomics provided additional insights into the mechanism underlying the retinal phenotypes of ApoD-/- and ApoD-/-ApoE-/- mice. Collectively, our data suggest that the APOD roles in the retina are context specific and could determine retinal glucose fluxes into different pathways. APOD and APOE do not play redundant, complementary or opposing roles in the retina, rather their interplay is more complex and reflects retinal responses elicited by lack of these apolipoproteins.

Polydatin alleviates high-fat diet induced atherosclerosis in apolipoprotein E-deficient mice by autophagic restoration.

BACKGROUND: Polydatin has been reported to possess remarkable anti-atherosclerotic activities. However, there are different opinions on its regulatory mechanisms. It remains unclear whether the anti-atherosclerotic mechanism of polydatin is related to its autophagic restoration or not. The aim of this study was to explore the question. METHODS: Using atherosclerotic model induced by high-fat diet in apolipoprotein E-deficient mice, the investigation was performed with polydatin alone or in combination with autophagic inhibitor or inducer intervention. Inhibitory sites of polydatin to PI3K were identified by molecular docking. RESULTS: Polydatin can significantly inhibit PI3K/Akt/mTOR pathway proteins expression, improve autophagic dysfunction and reduce atherosclerotic lesions. These effects could be antagonized and reinforced by adding autophagic inhibitor and inducer, respectively. Inhibitory sites of polydatin to PI3K were found to be ASP-810, SER-854, VAL-851, LEU-807, SER-774, LYS-802, ASP-933, SER-919, ASN-920, PHE-930, MEF-922, GLN-859 of PI3Kα. CONCLUSIONS: The mechanism of polydatin to alleviate atherosclerotic lesions was achieved by autophagic restoration.

Protective activities of distinct omega-3 enriched oils are linked to their ability to upregulate specialized pro-resolving mediators.

Clinical studies using a range of omega-3 supplements have yielded conflicting results on their efficacy to control inflammation. Omega-3 fatty acids are substrate for the formation of potent immune-protective mediators, termed as specialized pro-resolving mediators (SPM). Herein, we investigated whether observed differences in the potencies of distinct omega-3 supplements were linked with their ability to upregulate SPM formation. Using lipid mediator profiling we found that four commercially available supplements conferred a unique SPM signature profile to human macrophages, with the overall increases in SPM concentrations being different between the four supplements. These increases in SPM concentrations were linked with an upregulation of macrophage phagocytosis and a decreased uptake of oxidized low-density lipoproteins. Pharmacological inhibition of two key SPM biosynthetic enzymes 5-Lipoxygenase or 15-Lipoxygenase reversed the macrophage-directed actions of each of the omega-3 supplements. Furthermore, administration of the two supplements that most potently upregulated macrophage SPM formation and reprogrammed their responses in vitro, to APOE-/- mice fed a western diet, increased plasma SPM concentrations and reduced vascular inflammation. Together these findings support the utility of SPM as potential prognostic markers in determining the utility of a given supplement to regulate macrophage responses and inflammation.

Integrating systematic biological and proteomics strategies to explore the pharmacological mechanism of danshen yin modified on atherosclerosis.

This research utilized the systematic biological and proteomics strategies to explore the regulatory mechanism of Danshen Yin Modified (DSYM) on atherosclerosis (AS) biological network. The traditional Chinese medicine database and HPLC was used to find the active compounds of DSYM, Pharmmapper database was used to predict potential targets, and OMIM database and GeneCards database were used to collect AS targets. String database was utilized to obtain the other protein of proteomics proteins and the protein-protein interaction (PPI) data of DSYM targets, AS genes, proteomics proteins and other proteins. The Cytoscape 3.7.1 software was utilized to construct and analyse the network. The DAVID database is used to discover the biological processes and signalling pathways that these proteins aggregate. Finally, animal experiments and proteomics analysis were used to further verify the prediction results. The results showed that 140 active compounds, 405 DSYM targets and 590 AS genes were obtained, and 51 differentially expressed proteins were identified in the DSYM-treated ApoE-/- mouse AS model. A total of 4 major networks and a number of their derivative networks were constructed and analysed. The prediction results showed that DSYM can regulate AS-related biological processes and signalling pathways. Animal experiments have also shown that DSYM has a therapeutic effect on ApoE-/-mouse AS model (P < .05). Therefore, this study proposed a new method based on systems biology, proteomics, and experimental pharmacology, and analysed the pharmacological mechanism of DSYM. DSYM may achieve therapeutic effects by regulating AS-related signalling pathways and biological processes found in this research.

Vitamin D deficiency promotes large rupture-prone abdominal aortic aneurysms and cholecalciferol supplementation limits progression of aneurysms in a mouse model.

Vitamin D deficiency has been associated with human abdominal aortic aneurysm (AAA); however, its role in AAA pathogenesis is unclear. The aim of the present study was to investigate the effect of vitamin D deficiency on AAA development and examine if administering cholecalciferol (CCF) could limit growth of established AAA within the angiotensin-II (AngII) infused apolipoprotein E-deficient mouse model. Mice were rendered vitamin D deficiency through dietary restriction and during AngII infusion developed larger AAAs as assessed by ultrasound and ex vivo morphometry that ruptured more commonly (48% vs. 19%; P=0.028) than controls. Vitamin D deficiency was associated with increased aortic expression of osteopontin and matrix metalloproteinase-2 and -9 than controls. CCF administration to mice with established aortic aneurysms limited AAA growth as assessed by ultrasound (P<0.001) and ex vivo morphometry (P=0.036) and reduced rupture rate (8% vs. 46%; P=0.031). This effect was associated with up-regulation of circulating and aortic sclerostin. Incubation of human aortic smooth muscle cells with 1,25-dihyroxyvitamin D3 (the active metabolite of vitamin D) for 48 h induced up-regulation of sclerostin (P<0.001) and changed the expression of a range of other genes important in extracellular matrix remodeling. The present study suggests that vitamin D deficiency promotes development of large rupture-prone aortic aneurysms in an experimental model. CCF administration limited both growth and rupture of established aneurysms. These effects of vitamin D appeared to be mediated via changes in genes involved in extracellular matrix remodeling, particularly sclerostin.

Oral administration of Eucommia ulmoides Oliv. leaves extract protects against atherosclerosis by improving macrophage function in ApoE knockout mice.

Eucommia leaf extract (ELE) is a traditional Chinese herbal medicine. We investigated the effect of ELE on the development of atherosclerosis and changes in peritoneal macrophage function in apolipoprotein E knockout (ApoE-/- ) mice. At 8 weeks of age, ApoE-/- mice were randomly divided into three groups that were fed a high-fat diet blended with 0% (control), 5% or 10% ELE for a period of 7 weeks. The 10% ELE dose caused an approximately 36% reduction in atherosclerotic lesions, as estimated by oil red O staining. Real-time PCR analysis showed that the 1-week treatment with ELE reduced mRNA levels of Tnf-alpha, Il-1, and Mif in peritoneal macrophages isolated from the ApoE-/- mice. Furthermore, a 1-week treatment with the 10% ELE diet significantly reduced migration and adhesion functions in peritoneal macrophages. These results suggest that a 10% ELE diet reduces atherosclerotic lesions and modulates macrophage function by reducing cytokine expression. PRACTICAL APPLICATION: Eucommia leaf extract (ELE) is a traditional Chinese herbal medicine that reduces atherosclerotic lesions and suppresses inflammatory cytokines expression.

Bushen Jiangzhi formula reduces atherosclerosis in apoE-/- mice through autophagy.

OBJECTIVE: To study the effect of Bushen Jiangzhi formula (BSJZF) on atherosclerosis (AS) in apolipoprotein E knockout (apoE-/-) mice and the underlying mechanism. METHODS: We used a high fat diet to induce AS in apoE-/- mice. The mice were randomly divided into four groups: model, BSJZF, atorvastatin, and 3-methyladenine groups. Syngeneic C57BL/6 mice of the same age were used for the control group. Autophagosomes in the aorta were examined by transmission electron microscopy. Morphology, lipid accumulation, and collagen deposition in the aorta were examined by hematoxylin and eosin, Oil Red O, and Masson's staining, respectively. Serum levels of tumor necrosis factor alpha (TNF-), interferon gamma (IFN-), and interleukin 10 (IL-10) were measured by enzyme-linked immunoassays. Protein expression of microtubule-associated protein light chain 3 (LC3), Beclin 1, and p62 in the aorta were examined by Western blot analyses. RESULTS: ApoE-/- mice fed a high fat diet exhibited AS symptoms including less autophagosomes in the aorta, higher serum levels of TNF-a, IFN-r, and p62, and lower serum levels of IL-10, LC3, and Beclin 1. Treatment with BSJZF significantly reduced the area of the aortic plaque, decreased expression of TNF-a, IFN-r, and p62, and increased expression of IL-10, LC3, and Beclin 1. CONCLUSION: Our findings suggest that BSJZF promotes autophagy and reduces inflammation by regulating the expression of autophagy-related proteins LC3, Beclin 1, and p62, thereby effectively treating AS.

Improvement of Endothelial Dysfunction of Berberine in Atherosclerotic Mice and Mechanism Exploring through TMT-Based Proteomics.

Atherosclerosis is a multifactorial vascular disease triggered by disordered lipid metabolism, characterized by chronic inflammatory injury, and initiated by endothelial dysfunction. Berberine is the main active alkaloid of the herbal medicine Coptidis Rhizoma (Huanglian). Notably, berberine has been shown to have beneficial effects against atherosclerosis. However, the mechanisms of berberine in preventing atherosclerosis are still unclear. This study is aimed at investigating the effects and mechanisms of berberine in protecting the aorta and ameliorating atherosclerosis in apolipoprotein E-deficient (ApoE-/-) mice. Here, we demonstrated that berberine reduced serum lipid levels, antagonized hepatic lipid accumulation, improved intima-media thickening, and alleviated atherosclerotic lesions in ApoE-/- mice fed a western-type diet for 12 weeks. Meanwhile, berberine reduced aortic reactive oxygen species (ROS) generation and reduced the serum levels of malondialdehyde (MDA), oxidized low-density lipoprotein (ox-LDL), and interleukin-6 (IL-6). In aortic ring assay, berberine restored aortic endothelium-dependent vasodilatation in vivo and in vitro. Furthermore, 4,956 proteins were identified by proteomic analysis, and 199 differentially expressed proteins regulated by berberine were found to be involved in many biological pathways, such as mitochondrial dysfunction, fatty acid ß-oxidation I, and FXR/RXR activation. Summarily, these data suggested that berberine ameliorates endothelial dysfunction and protects against atherosclerosis, and thus may be a promising therapeutic candidate for atherosclerosis.

Dietary ß-Carotene Rescues Vitamin A Deficiency and Inhibits Atherogenesis in Apolipoprotein E-Deficient Mice.

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+ß-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 < 0.05). These results suggest that BC can be a sole source for VA and inhibits atherogenesis.

Reformulating Small Molecules for Cardiovascular Disease Immune Intervention: Low-Dose Combined Vitamin D/Dexamethasone Promotes IL-10 Production and Atheroprotection in Dyslipidemic Mice.

The targeting of proinflammatory pathways has a prophylactic and therapeutic potential on atherosclerotic cardiovascular diseases (CVD). An alternative/complementary strategy is the promotion of endogenous atheroprotective mechanisms that are impaired during atherosclerosis progression, such as the activity of tolerogenic dendritic cells (tolDC) and regulatory T cells (Treg). There is a need to develop novel low cost, safe and effective tolDC/Treg-inducing formulations that are atheroprotective and that can be of easy translation into clinical settings. We found that apolipoprotein E-deficient (ApoE-/-) mice treated with a low-dose combined formulation of Vitamin D and Dexamethasone (VitD/Dexa), delivered repetitively and subcutaneously (sc) promoted interleukin-10 (IL-10) production by dendritic cells and other antigen presenting cells in the lymph nodes draining the site of injection and the spleens. Expectedly, the treatment also increased the numbers of IL-10-producing CD4+ T cells. Concomitantly, the frequency of IFNγ-producing CD4+ and CD8+ T cells in the spleen, and the IFNγ response of splenocytes to polyclonal stimulation ex vivo were lower after VitD/Dexa treatment, indicating a reduced proatherogenic Th1 response. Interestingly, VitD/Dexa-treated mice had smaller atherosclerotic lesions, with reduced lipid content and lower inflammatory infiltrate of macrophages and T cells in the aortic root. No hypolipidemic or antioxidant effect could be detected, suggesting that a dominantly immunomodulatory mechanism of atheroprotection was engaged under the low-dose sc VitD/Dexa conditions used. Finally, no evidence of clinical, biochemical or immune toxicity was observed in treated ApoE-/- mice and, most importantly, C57BL/6 mice latently infected with Leishmania parasites and treated with an identical VitD/Dexa dose/scheme showed no clinical or microbiological signs of disease reactivation, suggesting the absence of general immunosuppression. Altogether, these results indicate that a non-toxic, non-immunosuppressive, low-dose of VitD/Dexa, administered subcutaneously and repetitively, exerts atheroprotective effects in dyslipidemic mice, apparently due to the induction of an IL-10-producing network of lymphoid and myeloid immune cells. These well known, widely available, and inexpensive small molecules can be easily co-formulated into a simple and accessible agent with a potential use as a prophylactic or therapeutic immune intervention for CVD and other chronic inflammatory diseases.

Dihydromyricetin increases endothelial nitric oxide production and inhibits atherosclerosis through microRNA-21 in apolipoprotein E-deficient mice.

Natural products were extracted from traditional Chinese herbal emerging as potential therapeutic drugs for treating cardiovascular diseases. This study examines the role and underlying mechanism of dihydromyricetin (DMY), a natural compound extracted from Ampelopsis grossedentata, in atherosclerosis. DMY treatment significantly inhibits atherosclerotic lesion formation, proinflammatory gene expression and the influx of lesional macrophages and CD4-positive T cells in the vessel wall and hepatic inflammation, whereas increases nitric oxide (NO) production and improves lipid metabolism in apolipoprotein E-deficient (Apoe-/- ) mice. Yet, those protective effects are abrogated by using NOS inhibitor L-NAME in Apoe-/- mice received DMY. Mechanistically, DMY decreases microRNA-21 (miR-21) and increases its target gene dimethylarginine dimethylaminohydrolase-1 (DDAH1) expression, an effect that reduces asymmetric aimethlarginine (ADMA) levels, and increases endothelial NO synthase (eNOS) phosphorylation and NO production in cultured HUVECs, vascular endothelium of atherosclerotic lesions and liver. In contrast, systemic delivery of miR-21 in Apoe-/- mice or miR-21 overexpression in cultured HUVECs abrogates those DMY-mediated protective effects. These data demonstrate that endothelial miR-21-inhibited DDAH1-ADMA-eNOS-NO pathway promotes the pathogenesis of atherosclerosis which can be rescued by DMY. Thus, DMY may represent a potential therapeutic adjuvant in atherosclerosis management.

Effective atherosclerotic plaque inflammation inhibition with targeted drug delivery by hyaluronan conjugated atorvastatin nanoparticles.

Atherosclerosis is associated with inflammation in the arteries, which is a major cause of heart attacks and strokes. Reducing the extent of local inflammation at atherosclerotic plaques can be an attractive strategy to combat atherosclerosis. While statins can exhibit direct anti-inflammatory activities, the high dose required for such a therapy renders it unrealistic due to their low systemic bioavailabilities and potential side effects. To overcome this, a new hyaluronan (HA)-atorvastatin (ATV) conjugate was designed with the hydrophobic statin ATV forming the core of the nanoparticle (HA-ATV-NP). The HA on the NPs can selectively bind with CD44, a cell surface receptor overexpressed on cells residing in atherosclerotic plaques and known to play important roles in plaque development. HA-ATV-NPs exhibited significantly higher anti-inflammatory effects on macrophages compared to ATV alone in vitro. Furthermore, when administered in an apolipoprotein E (ApoE)-knockout mouse model of atherosclerosis following a 1-week treatment regimen, HA-ATV-NPs markedly decreased inflammation in advanced atherosclerotic plaques, which were monitored through contrast agent aided magnetic resonance imaging. These results suggest CD44 targeting with HA-ATV-NPs is an attractive strategy to reduce harmful inflammation in atherosclerotic plaques.