Zanthoxylum nitidum extract attenuates BMP-2-induced inflammation and hyperpermeability.

Bone morphogenetic protein-2 (BMP-2) is commonly applied in spinal surgery to augment spinal fusion. Nevertheless, its pro-inflammatory potential could induce dangerous side effects such as vascular hyper-permeability, posing the need for manners against this condition. The present study aims to investigate the protective effect of Zanthoxylum nitidum (ZN) on BMP-2-related hyperpermeability and inflammation on the human umbilical vein endothelial cells (HUVECs). The results revealed that, in a concentration-dependent manner, BMP-2 enhanced the production of pro-inflammatory cytokines, including interleukin (IL)-1α, IL-1ß, and tumor necrosis factor-α, which were, however, suppressed by ZN. ZN inhibited BMP-2-induced inflammatory response by suppressing the phosphorylation of NF-κBp65 and IκB, and the abnormal nuclear translocation of p65. Moreover, the inhibited expression intercellular tight junction protein VE-cadherin and Occludin caused by BMP-2 was blocked by ZN. The hyper-permeability of HUVECs induced by BMP-2, as expressed as the higher fluorescent intensity of dextran, was also reversed by ZN. Overall, these findings demonstrated that ZN antagonized BMP-2-induced inflammation and hyperpermeability. It could be a therapeutic candidate for the treatment of BMP-2-induced side effects during spinal fusion.

Prevention of Vascular Inflammation by Pterostilbene via Trimethylamine-N-Oxide Reduction and Mechanism of Microbiota Regulation.

SCOPE: A gut-microbiota-dependent metabolite of L-carnitine, trimethylamine-N-oxide (TMAO), has been recently discovered as an independent and dose-dependent risk factor for cardiovascular disease (CVD). This study aims to investigate the effects of pterostilbene on reducing TMAO formation and on decreasing vascular inflammation in carnitine-feeding mice. METHODS AND RESULTS: C57BL/6 mice are treated with 1.3% carnitine in drinking water with or without pterostilbene supplementation. Using LC-MS/MS, the result shows that mice treated with 1.3% carnitine only significantly increased the plasma TMAO and pterostilbene supplementation group can reverse it. Additionally, pterostilbene decreases hepatic flavin monooxygenase 3 (FMO3) mRNA levels compared to carnitine only group. It appears that pterostilbene can alter host physiology and create an intestinal microenvironment favorable for certain gut microbiota. Gut microbiota analysis reveals that pterostilbene increases the abundance of Bacteroides. Further, pterostilbene decreases mRNA levels of vascular inflammatory markers tumor necrosis factor-α (TNF-α), vascular cell adhesion molecule 1 (VCAM-1), and E-selectin). CONCLUSION: These data suggest that amelioration of carnitine-induced vascular inflammation after consumption of pterostilbene is partially mediated via modulation of gut microbiota composition and hepatic enzyme FMO3 gene expression.

From the Cover: Zinc Deficiency Worsens and Supplementation Prevents High-Fat Diet Induced Vascular Inflammation, Oxidative Stress, and Pathological Remodeling.

Obesity has become a common public health problem in the world and raises the risk of various cardiovascular diseases. Zinc is essential for multiple organs in terms of normal structure and function. The present study investigated the effects of high fat diet (HFD) induced obesity on the aorta in mice, and evaluated whether it can be affected by zinc deficiency or supplementation. Four-week-old male C57BL/6J mice were fed HFD with varied amounts of zinc (deficiency, adequate and supplementation) for 3 and 6 months. Results showed that HFD feeding induced a time-dependent aortic remodeling, demonstrated by increased vessel wall thickness, tunica cell proliferation and fibrotic responses, and inflammatory response, reflected by increased expression of inflammatory cytokines (tumor necrosis factor-α and vascular cell adhesion molecule 1). HFD feeding also caused aortic oxidative damage, reflected by 3-nitrotyrosine and 4-hydroxy-2-nonenal accumulation, and down-regulated nuclear factor (erythroid-derived 2)-like 2 (Nrf2) expression and function, shown by down-regulation of its downstream antioxidants, catalase, NAD(P)H dehydrogenase (quinone 1), and metallothionein expression. The vascular effects of obesity-induced by HFD was exacerbated by zinc deficiency but significantly improved by zinc supplementation. In addition, down-regulation of Nrf2 function and associated antioxidants expression were also worsened by zinc deficiency but improved by zinc supplementation. These results suggest that HFD induces aortic remodeling, which can be exacerbated by zinc deficiency and improved by zinc supplementation.

The effects of garlic extract upon endothelial function, vascular inflammation, oxidative stress and insulin resistance in adults with type 2 diabetes at high cardiovascular risk. A pilot double blind randomized placebo controlled trial.

BACKGROUND AND AIMS: Endothelial dysfunction, vascular inflammation and oxidative stress have been integrally linked to the pathogenesis of both type 2 diabetes and cardiovascular disease. Aged Garlic Extract (AGE), a potent antioxidant, has been shown in previous studies to attenuate these novel risk factors in a non-diabetic population. AIMS: This study tested the hypothesis that AGE may improve endothelial function, oxidative stress, vascular inflammation and insulin resistance in high risk cardiovascular subjects with type 2 diabetes. METHODS: A double blind, placebo controlled crossover pilot study was performed in 26 subjects with type 2 diabetes who received 1200 mg of AGE or placebo daily for 4 weeks with a 4 week washout period. Plasma HsCRP was measured as a marker of inflammation. Plasma TAOS, blood GSH/GSSG and plasma LHP were measured as markers of oxidative stress/anti-oxidant defense. Insulin resistance was measured using the HOMA-IR method. Endothelial function was measured using change in the reflective index (RI) post-salbutamol using digital photoplethysmography and urinary albumin/creatinine ratio was measured as a biochemical surrogate. Measurements were taken at baseline and after intervention with AGE or placebo. RESULTS: Of the 26 patients studied (male 17, female 9), age was 61 ± 8 years (mean ± 1 SD), HbA1c 7.2 ± 1.1%, BP 130/75 ± 15.9/9.8 mmHg, total cholesterol 4.2 ± 0.81 mmol/l, triglyceride 2.11 ± 1.51 mmol/l, and HDL cholesterol 1.04 ± 0.29 mmol/l. The majority of patients were being treated with metformin (59%), aspirin (50%) and statin (96%) therapy. 36% were treated with an ACEI. There were no changes in these therapies throughout the study. Treatment with AGE had no significant effect upon the above metabolic parameters including insulin resistance. Treatment with AGE also had no significant effect on markers of endothelial function (plethysmography), oxidative stress (TAOS, GSH/GSSG, LHP) or inflammation (HsCRP). CONCLUSION: In this group of type 2 diabetic patients at high cardiovascular risk, 4 weeks treatment with AGE did not significantly improve endothelial function, vascular inflammation, oxidative stress or insulin resistance.

Eicosapentaenoic Acid Versus Docosahexaenoic Acid as Options for Vascular Risk Prevention: A Fish Story.

Vascular inflammation is a key component involved in the process of arthrosclerosis, which in turn increases the risk for cardiovascular injury. In the last 10 years, there have been many trials that looked at omega-3 fatty acids as a way to reduce cardiovascular risk. These trials observed the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the traditional lipid panel and found that both EPA and DHA reduce triglyceride (TG) level and increase high-density lipoprotein cholesterol (HDL-C) levels but also increase the low-density lipoprotein cholesterol (LDL-C) levels. In the 2 more recent trials, the MARINE and ANCHOR, EPA was given as an adjunct therapy to high-risk patients and not only was the traditional lipids measured but also examined the vascular inflammatory biomarkers. The results of these 2 trials not only showed reduction in cardiovascular risk because of reduction in vascular inflammation and reduction in the lipid panel but also showed that one of the MARINE-derived omega-3 fatty acid is superior to the other. Data search for omega-3 fatty acids and cardiovascular risk was performed, and articles were selected for review from 2006 to date. The research studies were all double-blind randomized trials except for one, which was a single-blind and focused on the effects of omega-3 fatty acids on the entire lipid panel. The participants received DHA/EPA and compared with a placebo group on the effect seen in the lipid panel. The first 7 studies looked at the effects of omega-3 fatty acids on TG, LDL-C, and HDL-C; of the 7, 1 directly compared DHA and EPA, 2 focused on EPA, and 4 were directed towards DHA alone. The MARINE and ANCHOR trials were more recent and also looked at the same parameter but also monitored vascular inflammatory biomarkers and how they were affected by omega-3 fatty acids. A second data search was performed for vascular biomarkers and cardiovascular risk, and articles that focused on high-sensitivity C-reactive protein and oxidized low-density lipoprotein were selected for review. Omega-3 fatty acids have shown to decrease TG level in multiple trials, but they have also shown to increase LDL and HDL levels, likely because omega-3 fatty acids promote TG conversion into HDL/LDL. The older data suggested that the benefits of omega-3 fatty acids are nullified by their effects on LDL levels. The data from the MARINE and ANCHOR trials have shown that EPA alone at 4 g per day has shown to decrease TG and total cholesterol without affecting the LDL levels. The earlier data showed that both EPA and DHA decreased TG level and increased levels of HDL-C, but that the DHA alone and direct comparison of DHA/EPA showed that DHA has more undesirable effects on LDL. Furthermore, the MARINE and ANCHOR trials have both shown that not only does EPA improve the lipid panel but also helps to decrease the levels of the vascular inflammatory biomarkers, thus further helping to decrease cardiovascular risk. The use of EPA as an adjunct therapy for high-risk patient has shown to help decrease cardiovascular risk. The reduction in risk is performed not only by decreasing TG but also by reducing vascular inflammation. Although because there are no randomized double-blind study looking at this, the research is inconclusive and requires further investigation.

Dietary proteins improve endothelial function under fasting conditions but not in the postprandial state, with no effects on markers of low-grade inflammation.

Endothelial dysfunction (ED) and low-grade inflammation (LGI) have a role in the development of CVD. The two studies reported here explored the effects of dietary proteins and carbohydrates on markers of ED and LGI in overweight/obese individuals with untreated elevated blood pressure. In the first study, fifty-two participants consumed a protein mix or maltodextrin (3×20 g/d) for 4 weeks. Fasting levels and 12 h postprandial responses of markers of ED (soluble intercellular adhesion molecule 1 (sICAM), soluble vascular cell adhesion molecule 1 (sVCAM), soluble endothelial selectin and von Willebrand factor) and markers of LGI (serum amyloid A, C-reactive protein and sICAM) were evaluated before and after intervention. Biomarkers were also combined into mean Z-scores of ED and LGI. The second study compared 4 h postprandial responses of ED and LGI markers in forty-eight participants after ingestion of 0·6 g/kg pea protein, milk protein and egg-white protein. In addition, postprandial responses after maltodextrin intake were compared with a protein mix and sucrose. The first study showed significantly lower fasting ED Z-scores and sICAM after 4 weeks on the high-protein diet (P≤0·02). The postprandial studies found no clear differences of ED and LGI between test meals. However, postprandial sVCAM decreased more after the protein mix compared with maltodextrin in both studies (P≤0·04). In conclusion, dietary protein is beneficial for fasting ED, but not for fasting LGI, after 4 weeks of supplementation. On the basis of Z-scores, postprandial ED and LGI were not differentially affected by protein sources or carbohydrates.

Effects of an energy-restricted diet rich in plant-derived α-linolenic acid on systemic inflammation and endothelial function in overweight-to-obese patients with metabolic syndrome traits.

Plant-derived α-linolenic acid (ALA) may reduce the risk of CVD, possibly by decreasing systemic inflammation and improving endothelial function. In the present study, the effects of a hypoenergetic diet rich in ALA (3·4 g/d) on the biomarkers of systemic inflammation and vascular function were investigated in eighty-one overweight-to-obese patients with metabolic syndrome traits in comparison with a hypoenergetic diet low in ALA (0·9 g/d, control). After a 6-month dietary intervention, there were significant decreases in the serum concentrations of C-reactive protein (CRP), TNF-α, IL-6, soluble intercellular adhesion molecule-1 (sICAM-1), soluble endothelial selectin (sE-selectin) and asymmetric dimethylarginine in both dietary groups. However, no inter-group differences were observed for all these changes. The serum concentration of YKL-40 (human cartilage glycoprotein 39 or chitinase-3-like protein 1) decreased after the ALA diet when compared with the control diet (P< 0·05 for time × treatment interaction). Plasma concentrations of fibrinogen did not significantly change in the two dietary groups. The decreases in the serum concentrations of sICAM-1, sE-selectin, CRP and YKL-40 were significantly correlated with the decreases in body fat mass. In conclusion, the present study indicates that in overweight-to-obese patients with metabolic syndrome traits, both vascular function and inflammation are improved during body-weight loss. The high ALA intake led to a more pronounced reduction in the serum concentration of YKL-40 compared with the intake of the low-ALA control diet, indicating the existence of independent favourable physiological effects of ALA during weight loss.

The interleukin-1ß modulator gevokizumab reduces neointimal proliferation and improves reendothelialization in a rat carotid denudation model.

OBJECTIVE: Excessive neointima formation often occurs after arterial injury. Interleukin-1ß (IL-1ß) is a potent pleiotropic cytokine that has been shown to regulate neointimal proliferation. We investigated the effects of the IL-1ß modulator gevokizumab in a rat carotid denudation model. METHODS: Sprague-Dawley rats were subjected to balloon denudation of the right carotid artery and were then randomized to receive a single subcutaneous infusion immediately after balloon injury of saline (control group, n = 13) or gevokizumab (gevokizumab groups, n = 15 in each group: 1, 10 and 50 mg/kg). We evaluated the treatment effects on carotid intima-media thickness (IMT) using ultrasonography, on endothelial regrowth using Evans Blue staining and on inflammatory response using histology. We also assessed the effects of IL-1ß and gevokizumab on human umbilical vein endothelial cells (HUVEC) and rat smooth muscle cells. RESULTS: We found that carotid IMT, in the proximal part of the denuded artery at day 28, was decreased by gevokizumab 1 mg/kg compared with controls. Neointima area and the intima/media area ratio were both reduced in the gevokizumab 1 mg/kg-treated group. Gevokizumab at the 1 mg/kg dose also improved endothelial regrowth. No effect was observed with gevokizumab 10 or 50 mg/kg. Gevokizumab also decreased the inflammatory effect of IL-1ß in in vitro cell experiments and protected HUVECs from IL-1ß's deleterious effects on cell migration, apoptosis and proliferation. CONCLUSION: A single administration of gevokizumab 1 mg/kg improves endothelial regrowth and reduces neointima formation in rats following carotid denudation, at least in part through its beneficial effects on endothelial cells.

Preventive and therapeutic effects of quercetin on lipopolysaccharide-induced oxidative stress and vascular dysfunction in mice.

Quercetin, a dietary antioxidant flavonoid, possesses strong anti-inflammatory and cytoprotective activities. The effects were investigated in an animal model of lipopolysaccharide (LPS)-induced endotoxaemia and vascular dysfunction in vivo. Male ICR mice were injected with LPS (10 mg/kg; i.p.). Quercetin (50 or 100 mg/kg) was intragastrically administered either before or after LPS administration. Fifteen hours after LPS injection, mice were found in endotoxaemic condition, as manifested by hypotension, tachycardia, and blunted vascular responses to vasodilators and vasoconstrictor. The symptoms were accompanied by increased aortic iNOS protein expression, decreased aortic eNOS protein expression, marked suppression of cellular glutathione (GSH) redox status, enhanced aortic superoxide production, increased plasma malodialdehyde and protein carbonyl, and elevated urinary nitrate/nitrite. Treatment with quercetin either before or after LPS preserved the vascular function, as blood pressure, heart rate, vascular responsiveness were restored to near normal values, particularly when quercetin was given as a preventive regimen. The vascular protective effects were associated with upregulation of eNOS expression, reduction of oxidative stress, and maintained blood GSH redox ratio. Overall findings suggest the beneficial effect of quercetin on the prevention and restoration of a failing eNOS system and alleviation of oxidative stress and vascular dysfunction against endotoxin-induced shock in mice.

Genistein prevents hyperglycemia-induced monocyte adhesion to human aortic endothelial cells through preservation of the cAMP signaling pathway and ameliorates vascular inflammation in obese diabetic mice.

Hyperglycemia-induced vascular inflammation resulting in the enhanced monocyte-endothelial cell (EC) interaction is the key event in the pathogenesis of atherosclerosis in diabetes. Here, we investigated the effect of isoflavone genistein on hyperglycemia-stimulated vascular inflammation. Human aortic EC (HAEC) were pretreated with genistein before the addition of high glucose (HG; 25 mmol/L) for 48 h. Genistein at a physiological concentration (0.1 µmol/L) significantly inhibited HG-induced adhesion of monocytes to HAEC and suppressed endothelial production of monocyte chemotactic protein-1 (MCP-1) and IL-8. Inhibition of adenylate cyclase or protein kinase A (PKA) significantly attenuated the antiadhesion effect of genistein. Consistently, genistein improved HG-impaired intracellular cAMP production and PKA activity in HAEC. Six-week-old diabetic db/db mice were untreated (db/db) or treated with a diet containing 1 g genistein/kg diet (db/db+G) for 8 wk. Their nondiabetic db/+ mice were used as normal controls. Circulating concentrations of MCP-1/JE and KC were significantly greater, whereas IL-10 concentrations were lower in db/db mice than those in normal mice. Dietary supplementation of genistein did not normalize but significantly suppressed the elevated serum concentrations of MCP-1/JE from 286 ± 30 ng/L to 181 ± 35 ng/L and KC from 321 ± 21 ng/L to 232 ± 20 ng/L while increasing that of IL-10 from 35 ± 4 ng/L to 346 ± 35 ng/L in db/db+G mice. Further, genistein treatment suppressed diabetes-induced adhesion of monocytes to EC by 87% and endothelial secretion of adhesion molecules. We conclude that genistein improves diabetes-caused vascular inflammation, which may be mediated through promoting the cAMP/PKA pathway.

Beneficial microvascular and anti-inflammatory effects of pravastatin during sepsis involve nitric oxide synthase III.

BACKGROUND: Sepsis induces microvascular inflammation and production of the vasodilator nitric oxide (NO) via endothelial and inducible nitric oxide synthase (eNOS or NOS III and iNOS or NOS II). Statins are cholesterol-lowering drugs; however, they also attenuate inflammation. This study aimed to determine whether pravastatin protected against sepsis-induced hypotension, loss of vascular tone, and microvascular inflammation via NOS pathways. METHODS: Male Wistar rats (n=18) were anaesthetized and the mesentery prepared for fluorescent intravital microscopy. Animals received either lipopolysaccharide (LPS; n=6); LPS+pravastatin (18 and 3 h before LPS; n=6), or saline as a control, for 4 h. RESULTS: Mean arterial pressure decreased in LPS-treated animals (P<0.05), but not in those also receiving pravastatin. Acetylcholine-induced relaxation of venules was abolished by LPS but improved by pravastatin. Pravastatin also reduced the increase in nitrite concentration and macromolecular leak from venules induced by LPS (P<0.05). The increased leucocyte adhesion seen in LPS-treated rats was also reduced in those also treated with pravastatin. Immunohistochemical analysis showed that pravastatin increased endothelial cell expression of NOS III during sepsis, but had no effect on LPS-induced up-regulation of NOS II. CONCLUSIONS: Pravastatin improved NOS III-mediated vessel relaxation and exerted anti-inflammatory effects within the microcirculation after LPS administration in rats. Pravastatin therefore appears to have beneficial effects during sepsis, as a result of increased microvascular expression and function of NOS III.

n-3 fatty acids prevent whereas trans-fatty acids induce vascular inflammation and sudden cardiac death.

n-3 PUFA have well-recognised cardio-beneficial effects. In contrast, premature coronary deaths are associated with consumption of high levels of trans-fatty acids (TFA). The present study determined the effects of n-3 PUFA and TFA on sudden cardiac death and vascular inflammation. A rat coronary ligation model was used to study the effect of fatty acids on sudden cardiac death, whereas a mouse femoral artery ligation model was used to study compensatory vascular remodelling. Human aortic endothelial cells (HAEC) were utilised for the in vitro studies to investigate expression of inflammatory molecules. Feeding animals an n-3 PUFA-enriched diet caused a sevenfold increase in plasma n-3 PUFA compared with that of the TFA-fed group, whereas a TFA-enriched diet caused a 2.5-fold increase in plasma TFA compared with the n-3 PUFA group. Animals on a TFA diet had a lower survival rate due to sudden cardiac death and exhibited variable degrees of aortic atherosclerotic lesions. Animals on a TFA diet had diminished hindlimb collateral growth, whereas animals on the n-3 PUFA diet exhibited extensive collateral growth about ligated regions. HAEC treated with TFA (trans-18 : 2) showed significantly increased expression of intracellular adhesion molecule-1 and nitrosylation of cellular proteins than those treated with DHA (n-3 PUFA, 22 : 6). The in vivo study demonstrates that, in contrast to TFA, n-3 PUFA improve animal survival after myocardial infarction, prevent development of atherosclerotic lesions and stimulate compensatory vascular remodelling. The in vitro study demonstrates that TFA induce, while n-3 PUFA prevent, vascular inflammation.

Effect of Benincasa hispida Cogniaux on high glucose-induced vascular inflammation of human umbilical vein endothelial cells.

Vascular inflammation is an important factor which can promote diabetic complications. Preliminary investigations of several crude plant extracts including aqueous extract of Benincasa hispida Cogniaux exhibit anti-inflammatory properties. This study investigates the mechanism of anti-vascular inflammatory activity of an aqueous extract of B. hispida Cogniaux (ABH) in human umbilical vein endothelial cells (HUVECs). The study was performed on HUVECs that were pretreated with various concentrations (1-20 microg/ml) of ABH before exposure with high glucose (25 mM) for 48 h. Cell ELISA and Western blot analysis showed that ABH inhibited high glucose-induced cell adhesion molecules (CAMs) surface and protein expression, resulting in reduced adhesion of U937 monocytes. ABH also inhibited the mRNA expression level of monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 (IL-8). High glucose-induced ROS production was inhibited by treatment of ABH. We observed that pretreatment with HUVECs with ABH blocks NF-kappaB activation via blocking phosphorylation and degradation of its inhibitory protein, IkappaB-alpha. ABH also reduced NF-kB promoter activity. These results suggest that ABH reduces high glucose-induced CAMs activation by inhibiting monocyte adhesion, ROS, and NF-kappaB in HUVECs.

Dehydroepiandrosterone inhibits the TNF-alpha-induced inflammatory response in human umbilical vein endothelial cells.

Dehydroepiandrosterone (DHEA) has a protective role against atherosclerosis. We determined the effect of pharmacological doses of DHEA upon the adhesion of monocytic U937 cells to human umbilical vein endothelial cells (HUVEC), as well as the expression of adhesion and chemoattractant molecules, the translocation of NF-kappaB, the degradation of IkappaB-alpha and the production of reactive oxygen species (ROS) in HUVEC. Adhesion of U937 cells to DHEA-treated HUVEC was evaluated by co-culture experiments using [(3)H]-thymidine-labeled U937 cells. The expression of adhesion and chemoattractant molecules was evaluated by flow cytometry and RT-PCR, respectively; NF-kappaB translocation was determined by Electrophoretic Mobility Shift Assay (EMSA) and IkappaB-alpha degradation by Western blot. ROS production was determined by the reduction of fluorescent DCFDA. TNF-alpha was used to induce inflammatory responses in HUVEC. One hundred micromolar of DHEA-treatment inhibited the TNF-alpha-induced expression of ICAM-1, E-selectin, ROS production and U937 cells adhesion to HUVEC, and interfered with NF-kappaB translocation and IkappaB-alpha degradation. DHEA at the above mention concentration also inhibited the mRNA expression of MCP-1 and IL-8 in basal conditions but not in TNF-alpha-stimulated conditions. Our results suggest that DHEA inhibits the expression of molecules involved in the inflammatory process, therefore it could be used as an alternative in the treatment of chronic inflammatory diseases such as atherosclerosis.

S18886, a selective TP receptor antagonist, inhibits development of atherosclerosis in rabbits.

OBJECTIVE: To investigate the effect of S18886, a novel TP (thromboxane A2 and prostaglandin endoperoxide) receptor antagonist, on the development of aortic fatty streaks and advanced lesions in a rabbit model of atherosclerosis and restenosis. METHODS AND RESULTS: The right iliac artery of 96 rabbits (8 groups, n=12/group) was balloon injured, then the animals were fed a cholesterol-enriched diet for 6 weeks. In Groups 1-4, concomitant oral administration of S18886 at 5 mg/kg/day over the 6-week-period reduced the intima to media ratio of lesions in the uninjured aorta and injured iliac artery, the accumulation of macrophages and the expression of ICAM-1 compared with 1 mg/kg/day S18886, 30 mg/kg/day aspirin and placebo, with no effect on body weight or plasma cholesterol levels. In Groups 5-8, 2 weeks of treatment with 5 mg/kg/day S18886 reduced the intima to media ratio of restenosing lesions when pre-formed iliac artery lesions underwent a second balloon injury at week 6. The smaller lesions resulting from S18886 treatment correlated with a significant decrease in the neointimal area occupied by macrophages, as well as in ICAM-1 expression, with no effect on the smooth muscle component. Aspirin treatment had no significant effect on the neointimal smooth muscle component, but partially inhibited macrophage infiltration, without inhibiting ICAM-1 expression. CONCLUSION: Inhibition of the TP receptor using S18886 causes a significant decrease in the recruitment of monocyte/macrophages within fatty streaks in the uninjured aorta and within primary and restenosing atherosclerotic lesions in the iliac artery of rabbits. Since TP receptor agonists, such as thromboxane A2, prostanoid endoperoxides and isoprostanes participate in vessel wall inflammation and are localized and increased in atherosclerotic plaques, treatment with S18886 may enhance atherosclerotic lesion stability by attenuating inflammatory processes that ultimately lead to plaque rupture.

Aldosteronism and a proinflammatory vascular phenotype: role of Mg2+, Ca2+, and H2O2 in peripheral blood mononuclear cells.

BACKGROUND: Chronic, inappropriate (relative to dietary Na+) elevations in circulating aldosterone, such as occur in congestive heart failure, are accompanied by a proinflammatory vascular phenotype involving the coronary and systemic vasculature. An immunostimulatory state with activated peripheral blood mononuclear cells (PBMCs) precedes this phenotype and is induced by a fall in cytosolic free [Mg2+]i and subsequent Ca2+ loading of these cells and transduced by oxidative/nitrosative stress. METHODS AND RESULTS: We sought to further validate this hypothesis in rats with aldosterone/1%NaCl treatment (ALDOST) by using several interventions as cotreatment: a Mg2+-supplemented diet; amlodipine, a CCB; and N-acetylcysteine, an antioxidant. Blood samples were obtained at weeks 1 to 4 of ALDOST to monitor [Mg2+]i, [Ca2+]I, and H2O2 production in PBMCs. Coronal ventricular sections were examined for invading inflammatory cells and 3-nitrotyrosine labeling, a marker of oxidative/nitrosative stress. In response to ALDOST and compared with untreated controls, we found an early and persistent reduction in [Mg2+]i with a subsequent rise in [Ca2+]i and H2O2 production, each of which was either attenuated or abrogated by the Mg2+-supplemented diet and by N-acetylcysteine, whereas amlodipine prevented Ca2+ loading and an altered redox state. Cotreatment with these interventions either markedly attenuated or prevented the appearance of the proinflammatory coronary vascular phenotype and the presence of 3-nitrotyrosine in invading inflammatory cells. CONCLUSIONS: We suggest that the immunostimulatory state that appears during aldosteronism and leads to a proinflammatory coronary vascular phenotype is induced by a fall in [Mg2+]i with Ca2+ loading of PBMCs and is transduced by H2O2 production in these cells.

Thermal treatment attenuates neointimal thickening with enhanced expression of heat-shock protein 72 and suppression of oxidative stress.

BACKGROUND: The beneficial effects of thermal therapy have been reported in several cardiovascular diseases. However, it is unknown whether the thermal treatment has some beneficial roles against the development of atherosclerosis. METHODS AND RESULTS: The inflammatory arterial lesion was introduced by placement of a polyethylene cuff on femoral arteries of male Sprague-Dawley rats for 4 weeks. Thermal-treated group underwent daily bathing in 41 degrees C hot water for 15 minutes. Neointimal thickening along with immunohistochemical expression of heat-shock proteins (HSPs), monocyte chemoattractant protein-1 (MCP-1), and NADPH oxidase were compared with those of a thermally untreated (Control) group. Morphometric analysis demonstrated a significant suppression of neointimal thickening in thermal-treated group compared with the Control group (intimal/medial area ratios, 0.01+/-0.01 versus 0.31+/-0.04, P<0.01). Expression of MCP-1 and infiltration of ED-positive cells were enhanced in the adventitial layer of Control. More importantly, expression of HSP72 in media was enhanced by thermal treatment. Expression of p22-phox, the major membrane subunit of NADPH oxidase, and MCP-1 was augmented in cuff-injured adventitia of the Control but not the thermal-treated groups. CONCLUSIONS: Thermal treatment significantly attenuated infiltration of inflammatory cells in adventitia and suppressed neointimal thickening in cuff-injured arteries with the enhancement of HSP72 expression and suppression of oxidative stress.

Thalidomide as a potent inhibitor of neointimal hyperplasia after balloon injury in rat carotid artery.

OBJECTIVE: Inflammation is one of the main pathogeneses of neointimal hyperplasia after coronary intervention. Thalidomide, because of its potent antiinflammatory and immunomodulatory properties, is being re-evaluated in several clinical fields. Therefore, we examined whether thalidomide therapy affects neointimal formation. METHODS AND RESULTS: In male Sprague-Dawley rats, 100 mg/kg of either thalidomide or sucrose (control) was administered daily from 3 days before injury to 2 weeks after conventional carotid artery denudation injury. Thalidomide administration resulted in a significant reduction of neointimal formation (neointima to media ratio 1.26+/-0.29 versus 0.35+/-0.13, P<0.001) and proliferative activity of vascular smooth muscle cells. In addition, arterial macrophage infiltration and local expressions of tumor necrosis factor alpha (TNF-alpha) and basic fibroblast growth factor (bFGF) in the injured arteries as measured by immunohistochemistry and immunoblot analysis were significantly reduced by thalidomide treatment. Serum TNF-alpha, measured by ELISA, was also significantly reduced in the thalidomide-treated animals compared with controls after injury (856+/-213 versus 449+/-68 pg/mL on day 3, P=0.001; 129+/-34 versus 63+/-18 pg/mL on day 14, P=0.001), and we observed a good positive correlation between the serum TNF-alpha levels and the severity of neointimal growth. CONCLUSIONS: We found that thalidomide, through its antiinflammatory and antiproliferative effects, significantly inhibits neointimal hyperplasia in balloon-injured rat carotid arteries. Our results suggest a potential role of thalidomide as a potent inhibitor of neointimal formation after angioplasty.