Icosapent ethyl therapy for very high triglyceride levels: a 12-week, multi-center, placebo-controlled, randomized, double-blinded, phase III clinical trial in China.

OBJECTIVES: Eicosapentaenoic acid in its ethyl ester form is the single active component of icosapent ethyl (IPE). This study was a phase III, multi-center trial assessing the safety and efficiency of IPE for treating very high triglyceride (TG) in a Chinese cohort. METHODS: Patients having TG levels (5.6-22.6 mmol/L) were enrolled and randomly assigned to receive a treatment of oral intake of 4 g or 2 g/day of IPE, or placebo. Before and after 12 weeks of treatment, TG levels were assessed and the median was calculated to determine the change between the baseline and week 12. In addition to examining TG levels, the impact of such treatments on other lipid changes was also investigated. The official Drug Clinical Trial Information Management Platform has registered this study (CTR20170362). RESULTS: Random assignments were performed on 373 patients (mean age 48.9 years; 75.1% male). IPE (4 g/day) lowered TG levels by an average of 28.4% from baseline and by an average of 19.9% after correction for placebo (95% CI: 29.8%-10.0%, P < 0.001). In addition, plasma concentration of non-high-density lipoprotein cholesterol (non-HDL-C), very low-density lipoprotein (VLDL) cholesterol, and VLDL-TG remarkedly reduced after IPE (4 g/day) treatment by a median of 14.6%, 27.9%, and 25.2%, respectively compared with participants in placebo group. Compared to the placebo, neither 4 nor 2 g of IPE daily elevated LDL-C levels with statistical significance. IPE was well tolerated by all the treatment groups. CONCLUSIONS: IPE at 4 g/day dramatically lowered other atherogenic lipids without a noticeable increase in LDL-C, thereby decreasing TG levels in an exceptionally high-TG Chinese population.

Interactions of ST-elevation myocardial infarction, age, and sex and the risk of major adverse cardiovascular events among Chinese adults: a secondary analysis of a single-centre prospective cohort.

OBJECTIVES: This study aimed to evaluate the interactions of ST-elevation myocardial infarction (STEMI), ageing and sex with respect to the incidence of major adverse cardiovascular events (MACE) among Chinese adults. DESIGN: Secondary analysis of a single-centre prospective cohort. SETTING: Patients who were admitted to cardiology clinics of the Affiliated Hospital of Jiangsu University due to acute myocardial infarction (MI) from June 2017 to November 2019 were eligible for inclusion in the study. This research only examined in-hospital cases. PARTICIPANTS: Patients aged <18 years or confirmed dead within 24 hours from admission were excluded. A total of 843 adults were included in the analysis. PRIMARY AND SECONDARY OUTCOME MEASURES: MACE was defined as any occurrence of cardiovascular mortality, MI recurrence, cardiogenic shock or heart failure. The relative excess risk due to interaction (RERI), attributable proportion (AP) and the synergy index were computed to quantify the interactions. Men without STEMI and adults without STEMI aged <60 years were the reference groups when examining the risk of MACE. RESULTS: The female participants with STEMI showed a statistically higher risk of MACE compared with the male participants without STEMI (relative risk (RR): 2.713, CI: 1.350 to 5.426, p=0.005). A 3.327 times higher risk of MACE was detected in the older adults with STEMI (aged ≥60 years) compared with the adults without STEMI aged <60 years (RR: 3.327, CI: 1.414 to 8.955, p=0.01). Older female patients also had an increased risk of MACE (RR: 3.033, CI: 1.432 to 6.777, p=0.005). A positive additive interaction was detected between STEMI and age (RERI: 1.917, CI: 0.196 to 3.637; AP: 0.576, CI: 0.174 to 0.979). STEMI and sex also indicated an additive interaction (AP: 0.459, CI: 0.018 to 0.899). CONCLUSION: In this Chinese population with MI, the risk of MACE was increased by about 2.7 times in women with STEMI compared with men without STEMI. MACE incidence increased by about 3.3 times in older patients with STEMI compared with younger patients without STEMI. STEMI and age, and STEMI and sex, may have a positive additive interaction.

A Case of Transcatheter Aortic Valve Replacement for the Treatment of Severe Aortic Stenosis with Multiple Organ Dysfunction.

A 77-year-old woman with extremely high risk of mortality due to severe aortic stenosis (AS) and multiple organ failure was admitted to the affiliated hospital of Jiangsu University. She did not receive regular treatment since being diagnosed with AS 17 months previously. Frequent breakout of acute left heart failure after admission, with a low ostium of the left coronary artery showed by computed tomography, the patient underwent transcatheter aortic valve replacement (TAVR). Though cardiac conduction system abnormalities and a short-term elevation of pulmonary arterial pressure occurred in this patient after TAVR, she eventually recovered and her quality of life improved significantly. As the population adapted to TAVR keeps expanding, we believe this operation will play a more important role in the treatment of AS patients.

The TIR/BB-loop mimetic AS-1 prevents Ang II-induced hypertensive cardiac hypertrophy via NF-κB dependent downregulation of miRNA-143.

Untreated pathological cardiac hypertrophy, which can be caused by sustained systemic hypertension, may lead to heart failure. In the present study, we investigated whether AS-1 had attenuating effects on hypertension-induced cardiac hypertrophy, and whether this process was mediated by the regulation of miRNA-143. To induce the hypertrophic response in vitro, cardiomyocytes were stimulated with Ang II for 24hs. AS-1 administration strongly attenuated Ang II-induced hypertrophic response of cardiomyocytes. Chronical infusion of Ang II via implanted osmotic mini-pump induced increased blood pressure and cardiac hypertrophy in vivo. AS-1 administration attenuated hypertension-induced cardiac hypertrophy by, at least in part, inhibin of MAPK signaling. We observed, for the first time, upregulated expression of miRNA-143 in Ang II-induced cardiomyocytes, and inhibition of miRNA-143 significantly reduced the Ang II-induced hypertrophic responses. Importantly, AS-1 administration diminished the Ang II-induced upregulation of miRNA-143. Overexpression of miRNA-143 abolished the attenuating effects of AS-1 on Ang II-induced hypertrophic response of cardiomyocytes. Additionally, AS-1 administration abrogates Ang II-induced nuclear translocation of p50 NF-κB subunit in hypertrophic cardiomyocytes. Application of NF-κB inhibitor significantly suppressed Ang II-induced upregulation of miRNA-143. Our data suggest a novel mechanism by which AS-1 attenuates Ang II-induced hypertrophic response through downregulation miRNA-143 expression in a NF-κB-dependent manner.

Anti-Diabetic and Anti-Nephritic Activities of Grifola frondosa Mycelium Polysaccharides in Diet-Streptozotocin-Induced Diabetic Rats Via Modulation on Oxidative Stress.

Grifola frondosa is an edible fungus with a variety of potential pharmacological activities. This study investigates the hypoglycemic, anti-diabetic nephritic, and antioxidant properties of G. frondosa polysaccharides in diet-streptozotocin-induced diabetic rats. After a 4-week treatment with 100 mg/kg of metformin and 200 mg/kg of one of four different G. frondosa polysaccharide mixtures (especially GFPS3 and GFPS4), diabetic rats had enhanced body weight and suppressed plasma glucose, indicating the hypoglycemic activities of the G. frondosa polysaccharides. G. frondosa polysaccharides regulated the level of serum creatinine, blood urea nitrogen, N-acetyl-ß-D-glucosaminidase, and albuminuria; inhibited the serum levels of interleukin (IL)-2, IL-6, and TNF-α; and enhanced the serum levels of matrix metalloproteinase 9 and interferon-α, confirming their anti-diabetic nephritic activities. G. frondosa polysaccharides ameliorated the pathological alterations in the kidneys of diabetic rats. Moreover, G. frondosa polysaccharides modulated the serum levels of oxidant factors such as superoxide dismutase, glutathione peroxidase, catalase, malondialdehyde, and reactive oxygen species, revealing their antioxidant properties. Furthermore, the administration of G. frondosa polysaccharides inhibited nuclear factor kappa B activities in the serum and kidneys. All of the data revealed that the activation of nuclear factor kappa B plays a central role in G. frondosa polysaccharide-mediated anti-diabetic and anti-nephritic activities.

Docosahexaenoic acid inhibits monocrotaline-induced pulmonary hypertension via attenuating endoplasmic reticulum stress and inflammation.

Endoplasmic reticulum (ER) stress and inflammation contribute to pulmonary hypertension (PH) pathogenesis. Previously, we confirmed that docosahexaenoic acid (DHA) could improve hypoxia-induced PH. However, little is known about the link between DHA and monocrotaline (MCT)-induced PH. Our aims were, therefore, to evaluate the effects and molecular mechanisms of DHA on MCT-induced PH in rats. Rat PH was induced by MCT. Rats were treated with DHA daily in the prevention group (following MCT injection) and the reversal group (after MCT injection for 2 wk) by gavage. After 4 wk, mean pulmonary arterial pressure (mPAP), right ventricular (RV) hypertrophy index, and morphological and immunohistochemical analyses were evaluated. Rat pulmonary artery smooth muscle cells (PASMCs) were used to investigate the effects of DHA on cell proliferation stimulated by platelet-derived growth factor (PDGF)-BB. DHA decreased mPAP and attenuated pulmonary vascular remodeling and RV hypertrophy, which were associated with suppressed ER stress. DHA blocked the mitogenic effect of PDGF-BB on PASMCs and arrested the cell cycle via inhibiting nuclear factor of activated T cells-1 (NFATc1) expression and activation and regulating cell cycle-related proteins. Moreover, DHA ameliorated inflammation in lung and suppressed macrophage and T lymphocyte accumulation in lung and adventitia of resistance pulmonary arteries. These findings suggest that DHA could protect against MCT-induced PH by reducing ER stress, suppressing cell proliferation and inflammation.

Plasminogen activator inhibitor links obesity and thrombotic cerebrovascular diseases: The roles of PAI-1 and obesity on stroke.

One of the global socioeconomic phenomena occurred during the last decades is the increased prevalence of obesity, with direct consequence on the risk of developing thrombotic disorders. As the physiological inhibitor of tissue plasminogen activator (tPA) and urokinase plasminogen activator (uPA), plasminogen activator inhibitor-1 (PAI-1) is well known for its role in fibrinolysis. More and more evidences have shown that PAI-1 involves in physiopathologic mechanisms of many diseases and metabolic disorder. Increased serum level of PAI-1 has been observed in obesity and it also contributes to the development of adipose tissue and then has effects on obesity. Meantime, obesity affects also the PAI-1 levels. These evidences indicate the complicated interaction between PAI-1 and obesity. Many clinic studies have confirmed that obesity relates to the stroke outcome although there are many contradictory results. Simultaneously, correlation is found between plasma PAI-1 and thrombotic cerebrovascular diseases. This article reviews contemporary knowledge regarding the complex interplay of obesity, PAI-1 and stroke.

The role of nuclear factor of activated T cells in pulmonary arterial hypertension.

Nuclear factor of activated T cells (NFAT) was first identified as a transcription factor about 3 decades ago and was not well studied until the development of immunosuppressant. Numerous studies confirm that calcineurin/NFAT signaling is very important in the development of vasculature and cardiovascular system during embryogenesis and is involved in the development of vascular diseases such as hypertension, atherosclerosis and restenosis. Recent studies demonstrated that NFAT proteins also regulate immune response and vascular cells in the pulmonary microenvironment. In this review, we will discuss how different NFAT isoforms contribute to pulmonary vascular remodeling and potential new therapeutic targets for treating pulmonary arterial hypertension.

CML/RAGE signal induces calcification cascade in diabetes.

OBJECTIVE: Vascular calcification is a significant predictor of coronary heart disease events, stroke, and lower-limb amputation. Advanced glycation end-products (AGEs) play a key role in the development of vascular calcification. However, the role of Nε-carboxymethyl-lysine (CML), a major active ingredient of heterogeneous AGEs, in the development of atherosclerotic calcification in diabetic patients and the underlying mechanism remain unclear. Hence, the role and the mechanism of CML in the transmission pathway of diabetic calcification cascade were investigated in the present study. METHODS: In vivo and in vitro investigations were performed. In study I, 45 diabetic patients hospitalized for above-knee amputation in the Department of Orthopedics, Affiliated Hospital of Jiangsu University were recruited from February 2010 to June 2015. The patients were categorized based on the severity of anterior tibial artery stenosis, which was assessed by color Doppler ultrasound, into mild stenosis (0% < stenosis < 50%, n = 15), moderate stenosis (50 ≤ stenosis < 70%, n = 15), and severe stenosis/occlusion groups (70 ≤ stenosis ≤ 100%, n = 15). In study II, the specific mechanism of CML in the transmission pathway of the diabetic calcification cascade signal was investigated in A7r5 aortic smooth muscle cells under high-lipid, apoptosis-coexisting conditions. ELISA (for serum CML concentration of patients), ultrasound (for plaque size, calcification, blood flow filling, vascular stenosis etc.), H&E staining (for plaque morphology), vonKossa staining (for qualitative analysis of calcification), calcium content assay (for quantitative analysis of calcification), and Western blot analyses of CML, receptor for advanced glycation end products (RAGE), NADPH oxidase 4, phosphorylated p38, core-binding factor α1 (cbfα1), alkaline phosphatase (ALP) and ß-actin were then performed. RESULTS: Morphological analysis revealed extensive calcification lesions in the intima and media of the anterior tibial artery. The extent and area of calcium deposition in the intima significantly increased with disease progression. Interestingly, spotty calcification was predominant in the atherosclerotic plaques of diabetic patients with amputation, and macrocalcification was almost invisible. Pearson correlation analysis revealed that serum CML level exhibited a significant positive correlation with calcium content in the arterial wall (R2 = 0.6141, P < 0.0001). Semi-quantitative Western blot analysis suggested that the intensity of CML/RAGE signal increased with progression of atherosclerotic calcification in diabetic patients. In subsequent in vitro study, the related pathway was blocked by anti-RAGE antibody, NADPH oxidase inhibitor DPI, p38MAPK inhibitor SB203580, and anti-cbfa1 antibody in a step-wise manner to observe changes in calcium deposition and molecular signals. Results suggested that CML may play a key role in atherosclerotic calcification mainly through the CML/RAGE- reactive oxygen species (ROS)-p38MAPK-cbfα1-ALP pathway. CONCLUSION: Spotty calcification was predominant in the atherosclerotic plaques of amputated diabetic patients. CML/RAGE signal may induce the calcification cascade in diabetes via ROS-p38MAPK.

[Nuclear factor-κB pathway mediates the effects of CD137 signaling on NFATc1 expression in mice vascular smooth muscle cells].

OBJECTIVE: To observe whether CD137 signaling could affect the nuclear factor of activated T cells c1 (NFATc1) expression through nuclear factor-κB (NF-κB) pathway in mice aortic vascular smooth muscle cells (VSMCs). METHODS: Adherence methods for tissues explants were used for primary culture of mouse aortic VSMCs. The mRNA expression of CD137 and NFATc1 was detected by real-time quantitative PCR (RT-qPCR). The VSMCs protein expression of IκB-α, NF-κB p65, phospo-p65 and NFATc1 was determined by Western blot. The level of CD137 was measured by Flow Cytometry (FCM). RESULTS: (1) The mRNA and protein expression of CD137 in VSMCs was significantly upregulated at 24 h after co-culture with TNF-α (10 ng/ml, all P < 0.05). (2) Compared with the control group, the level of p-NF-κB p65 in cytoplasm and nucleus was significantly increased (8.34 ± 0.28 vs. 1, P < 0.05, and 2.64 ± 0.42 vs. 1, P < 0.05) while the level of IκB-α was reduced (1 vs. 2.70 ± 0.28, P < 0.05) after co-treatment with agonist-CD137 mAb, above effects were partly blocked by adding specific NF-κB inhibitor PDTC (30 µmol/L: 1.15 ± 0.14 vs. 8.34 ± 0.28, P < 0.05, and 2.09 ± 0.12 vs. 2.64 ± 0.42, P < 0.05, and 1.78 ± 0.74 vs. 1, P < 0.05). (3) The mRNA (2.07 ± 0.09 vs. 1, P < 0.05) and protein (1.75 ± 0.07 vs. 1, P < 0.05) expression of NFATc1 was significantly upregulated by agonist CD137mAb compared with the control group, and these effects could be reversed by PDTC (1.15 ± 0.07 vs. 2.07 ± 0.09, P < 0.05, and 0.90 ± 0.11 vs. 1.75 ± 0.07, P < 0.05). CONCLUSION: CD137 signaling could affect the NFATc1expression in VSMCs through NF-kappaB pathway.

Effects of thiazolidinedione therapy on inflammatory markers of type 2 diabetes: a meta-analysis of randomized controlled trials.

BACKGROUND: Inflammation is a common feature in patients with type 2 diabetes mellitus (T2DM). This meta-analysis aimed to assess the influence of thiazolidinedione (TZD) therapy on the circulating levels of inflammatory markers in patients with T2DM. METHODS AND RESULTS: We searched the databases Medline, Embase, ScienceDirect, Web of Science, SpringerLink, and the Cochrane Library for randomized controlled trials (RCTs) that examined the effects of thiazolidinedione vs. a placebo on patients with T2DM. The main outcomes were absolute changes in levels of circulating inflammatory markers. Twenty-seven RCTs were included and data were analyzed using a fixed-effect model or a random-effect model based on heterogeneity. Pooled results indicated that circulating levels of high-sensitivity C reactive protein (hsCRP; SMD = -0.65, 95% CI = -0.98 to -0.32, p < 0.01), monocyte chemoattractant protein-1 (MCP-1; WMD = -54.19, 95% CI = -73.86 to -34.52, p < 0.01), von Willebrand factor% (vWF%; WMD = -8.18, 95% CI = -13.54 to -2.81, p 0.01), fibrinogen (SMD = -0.26, 95% CI = -0.41 to -0.11, p < 0.01) and E-selectin(WMD = -3.57, 95% CI = -5.59 to -1.54, p <0.01) were significantly decreased after TZD therapy. However, interleukin-6 (IL-6), matrix metalloproteinase-9 (MMP-9), soluble CD40 ligand, plasminogen activator inhibitor 1 (PAI-1) and intercellular adhesion molecule (ICAM-1) were not significantly affected. Subgroup analyses of PAI-1, vWF% and fibrinogen in terms of trial drugs showed significant reductions for rosiglitazone (all p valuses< 0.05), but not pioglitazone treatment. Conversely, the E-selectin (p < 0.01) lowering effect only existed in the pioglitazone group. Further, rosiglitazone and pioglitazone treatment reduced serum hsCRP and MCP-1 but had no marked effects on MMP-9, IL-6 and ICAM-1. CONCLUSIONS: Limited evidence suggested that TZD therapy had anti-inflammatory property that might contribute to its beneficial effect on inflammatory state in patients with type 2 diabetes.

[Impact of new regional cooperative rescue model on first medical contact to balloon time and outcome in patients with ST-segment elevation myocardial infarction].

OBJECTIVE: To evaluate the effect of new regional cooperative rescue model on the first medical contact-to-balloon time and outcome in patients with ST-elevation myocardial infarction. METHOD: Patients with acute myocardial infraction (AMI) and onset time within 24 hours transferred from other hospitals to our clinic and underwent emergent percutaneous coronary intervention (PCI) between January 2010 and January 2013 were included in this study. Patients were divided into two groups: regional cooperative treatment group (n = 230) and control group (n = 168) according to whether the first contact clinic belongs to the regional cooperative rescue model or not. The first medical contact to balloon (FMC-to-B) time, door to balloon (D-to-B) time, referral time, cardiac function, mean cost, days of hospitalization, and major adverse cardiac event (MACE) during the 6 months follow up were compared. RESULTS: Mean FMC-to-B time, D-to-B time and referral time were significantly decreased from (212 ± 37), (107 ± 18), (103 ± 23) min (control group) to (98 ± 23), (25 ± 7), (62 ± 12) min respectively in regional cooperative treatment group. Mean medical cost (42 221 (23 184, 77 768) RMB vs. 49 654 (25 126, 122 433) RMB) and days of hospitalization (7 (5, 13) days vs. 10 (6, 20) days) were also significantly lower in regional cooperative treatment group than in control group. At 6 months follow up, LVEF was significantly higher(54.9% ± 8.6% vs. 48.9% ± 9.1%, P = 0.01), LVEDD ((48.9 ± 5.7)mm vs.(51.4 ± 6.0) mm, P < 0.01) as well as MACE rate (7.4% (17/230) vs. 17.9% (30/168) , P < 0.05) were significantly lower in regional cooperative treatment group than in control group. CONCLUSION: The regional cooperative rescue model can decrease the FMC-to-B time, improve cardiac function, and reduce both patients' financial burden and MACE in patients with acute myocardial infarction.

[CD147 expression level and rs8259 T/A polymorphism of CD147 in patients with acute coronary syndrome].

OBJECTIVE: To investigate the association between CD147 expression and its untranslated regions 3'UTR rs8259 T/A polymorphism and acute coronary syndrome (ACS). METHODS: The genotypes of CD147 were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods in 182 ACS patients and 328 healthy controls. The plasma level of CD147 was determined by enzyme-linked immunosorbent assay (ELISA). CD147 mRNA and protein expression was detected by real-time fluorescent quantitative PCR (RT-qPCR) and Western blot. RESULTS: The plasma CD147 level obtained from radial artery in ACS patients ((3.63 ± 0.70) pg/L) was significantly higher than in control ((2.45 ± 0.27) pg/L, P < 0.05), and highest in plasma obtained from the coronary artery ((4.28 ± 1.03) pg/L, P < 0.05) in ACS patients. Furthermore, the plasma CD147 level was higher in the ACS patients with rs8259 AA genotype than in the ACS patients with rs8259 TT genotype ((4.08 ± 0.41) pg/L vs. (3.05 ± 0.79) pg/L in radial artery and (5.29 ± 0.62) pg/L vs. (3.13 ± 0.52) pg/L in coronary artery, both P < 0.05). There are an enhanced expression of CD147 mRNA (2.45 times higher than control) and protein (3.66 ± 1.56 vs. 1.81 ± 1.29) in PBMCs from ACS patients than that from controls (both P < 0.05). The PBMCs CD147 mRNA and protein expression level were significantly higher in ACS patients with rs8259 AA genotype (mRNA:2.45 ± 0.35, protein:1.63 ± 0.16) compared to ACS patients with rs8259 TT genotype (mRNA:1.69 ± 0.15, protein: 0.88 ± 0.16, both P < 0.05). Multiple logistic analysis showed that CD147 T allele (AT+TT) was a protective factor to ACS (OR = 0.667, 95% CI 0.507-0.879, P < 0.05). CONCLUSIONS: The over-expression of CD147 is involved in the pathogenesis of ACS. The CD147 3'UTR rs8259 T allele may be a protective factor for ACS, its polymorphism can affect the CD147 protein expression in ACS patients.

[Effects of docosahexaenoic acid on hypoxia-induced pulmonary arterial hypertension].

OBJECTIVE: To investigate the effects of docosahexaenoic acid (DHA) on hypoxia-induced pulmonary arterial hypertension(PAH) and the mechanism. METHODS: PAH was induced by chronic intermittent hypoxia for 21 days in vivo. Forty male Sprague-Dawley rats were randomly divided into 4 groups (n = 10, each):a normal control group, DHA-treated groups in normoxia and hypoxia, and a PAH group. At the end of study, mean pulmonary arterial pressure (mPAP), right ventricular hypertrophy and the index of wall thickness of small pulmonary artery (WT% and WA%) among groups were compared. The changes of pulmonary arterial smooth muscle cell (PASMC) proliferation were determined by MTT in vitro. Migration assay was performed using the Boyden chamber. Real-time quantitative PCR was performed to quantify mRNA levels of the smooth muscle cell phenotype markers SM-α-actin, calponin and SM 22α under normoxic or hypoxic conditions, in the absence or presence of DHA. RESULTS: DHA treatment significantly lowered mPAP [(22.7 ± 1.8) mmHg (1 mmHg = 0.133 kPa)], reduced thickening of small pulmonary artery wall [WT%:(21.6 ± 4.1)%, WA%: (52.0 ± 2.9)% ] and alleviated ventricular hypertrophy (34.2 ± 2.2) % compared to those of the hypoxic group (P < 0.05). DHA inhibited the proliferation, migration and phenotype switching of PASMCs induced by hypoxia in vitro. CONCLUSION: DHA therapy reduced mPAP in a rat model of hypoxia-induced PAH and this effect was linked with inhibition of pulmonary vascular remodelling.

Docosahexaenoic acid attenuates hypoxic pulmonary vasoconstriction by activating the large conductance Ca2+-activated K+ currents in pulmonary artery smooth muscle cells.

BACKGROUND: The inhibition of potassium (K(+)) channels plays an important role in pulmonary circulation for its close relationship with hypoxic pulmonary vasoconstriction (HPV). Docosahexaenoic acid (DHA), a n-3 polyunsaturated fatty acid, is well known for its prevention and treatment of cardiovascular diseases. However the role which DHA plays in HPV remains unclear. Here, we tested the hypothesis that DHA contributes to pulmonary vascular tone by activating the large conductance Ca(2+)-activated K(+) (BKCa) channels via calcium sparks. METHODS AND RESULTS: Isolated resistance pulmonary artery preparation was used to study the vasomotor response to DHA. Pulmonary artery smooth muscle cells (PASMCs) were isolated from third- to fourth order branches of pulmonary arteries by collagenase digestion method. BKCa and the voltage-dependent potassium channel (Kv) currents in PASMCs were measured by the whole-cell patch-clamp technique. Fluo-8 was used as a fluorescence indicator for the real-time measurement of calcium dynamics in PASMCs. DHA dilated resistance pulmonary arteries in a dose-dependent manner in hypoxic or normoxic solution, and the effects of DHA were abolished after pre-treatment with heparin (100 µg/ml), a 1,4,5-triphosphate (IP3) receptor (IP3R) inhibitor or iberiotoxin (100 nmol/L), a specific inhibitor of BKCa channel. DHA activated BKCa channels in a dose-dependent manner, however, the activation induced by DHA was not seen in PASMCs pre-incubated with heparin. While the Kv currents decreased from 102.6 ± 5.4 to 36.5 ± 6.7 pA/pF by addition of 10 µmol/L DHA. DHA also caused calcium sparks in PASMCs. Moreover, hypoxia inhibited BKCa currents in PASMCs, but this inhibition was reversed by DHA. CONCLUSION: Our findings suggest that DHA is a novel BKCa opener in PASMCs, which may indicate a potential therapeutic role in HPV.

Docosahexaenoic acid inhibits development of hypoxic pulmonary hypertension: in vitro and in vivo studies.

BACKGROUND: Hypoxic pulmonary hypertension (HPH) is initiated by acute hypoxic pulmonary vasoconstriction followed by vascular remodeling and right ventricular failure. Numerous studies have shown that long-term supplementation with docosahexaenoic acid (DHA) may have a role in preventing cardiovascular disease. However, the effects of DHA on HPH remain unclear. Extracellular signal-regulated kinase 1/2 (ERK1/2) is known to be involved in the proliferation and migration of various cell types. In this study, we determined the role of DHA in the prevention of HPH via the ERK1/2 signal pathway. METHODS: Rats were intragastrically administered with saline or DHA (100 mg) daily before exposure to room air or chronic hypoxia (O(2) content was maintained at 10%) for 8 h a day for 3 weeks. At the end of study, we compared the right ventricular systolic pressure (RVSP), the weight ratio of right ventricular (RV) free wall to the left ventricular (LV) including the septum (S) free wall, the percent wall thickness (wt.%) of small pulmonary arteries and the area of α-smooth muscle actin (α-SMA)-positive pulmonary artery smooth muscle cells (PASMCs) in the pulmonary arteries among the rats. In vitro, the proliferation and migration of PASMCs were through an MTT assay and a Boyden chamber, respectively. The phenotype marker expression and ERK1/2 activation in the PASMCs were through real-time PCR and western blot analysis, respectively. RESULTS: Under hypoxia, DHA treatment reduced the RVSP (20.41 mmHg ± 2.18 vs. 35.46 mmHg ± 3.21; P < 0.05), the weight ratio of RV free wall to left ventricular and septal free wall [RV/(LV + S)] (0.27 ± 0.03 vs. 0.38 ± 0.05; P < 0.05), wt.% (17.45 ± 1.58% vs. 59.65 ± 4.59%; P < 0.05) and the percentage of SMA-positive vessels (55.42 ± 5.18% vs. 84.71 ± 6.22%; P < 0.05) compared with those of the saline-treated rats. Hypoxia promoted the proliferation, migration and phenotype switching of PASMCs in vitro. However, DHA treatment suppressed the hypoxia-induced changes. Additionally, DHA attenuated the expression of hypoxia-activated ERK1/2 in the PASMCs. CONCLUSIONS: Our observations indicate that DHA may potentially prevent HPH.

SRC kinase family inhibitor PP2 promotes DMSO-induced cardiac differentiation of P19 cells and inhibits proliferation.

BACKGROUND: It has been reported recently that PP2, a Src family kinase inhibitor, promotes selective cardiogenesis in embryonic stem cells. However, there is no other research proved pro-cardiogenic characteristic of PP2 so far. In this study, we explored the potential cardiogenic effect of PP2 on P19 cells differentiation. METHODS: P19-αMHC-EGFP cell line was established by transfecting P19 cells with αMHC-EGFP vector in order to evaluate cardiogenesis with EGFP. P19-αMHC-EGFP cells and P19 cells were induced to differentiate into cardiomyocytes with 1%DMSO, 5 µmol/L PP2, or both 1%DMSO and 5 µmol/L PP2. Differentiated cells from P19-αMHC-EGFP cells were then assessed under confocal microscope. Western-blot and RT-PCR were also performed to detect expression of cardiac troponin I and cardiac transcription factors respectively. In addition, the effects of PP2 on proliferation of P19 cells were further examined using Cell Counting Kit-8. RESULTS: EGFP positive cells were firstly detected on day 7 and PP2 alone cannot induce efficient cardiac differentiation of P19-αMHC-EGFP cells. However PP2 supplementation dramatically increases DMSO induced cardiac differentiation than DMSO alone. It was also found that PP2 inhibit proliferation of P19 cells in both a dose-dependent manner and a time-dependent manner. CONCLUSION: PP2 alone cannot substitute DMSO to induce cardiac differentiation, however, PP2 supplementation drastically promotes DMSO-induced cardiac differentiation of P19 cells. The increased percentages of differentiated cardiac myocytes is partly resulting from cell proliferative inhibit effect of PP2 in undifferentiated P19 cells. P19-αMHC-EGFP cell line has the potential to be used for regenerative therapies in experimental models of heart repair.

[Effect of the costimulatory molecules OX40-OX40 ligand interaction on the expression of NFATc1 in leukocytes of apolipoprotein E-deficient mice].

OBJECTIVE: To investigate the effect of OX40/OX40L interaction on the nuclear factor of activated T cells c1 (NFATc1) in ApoE-/- mice. METHODS: Lymphocytes were prepared from mouse spleens after Collar-treated Surgery, then incubated with a range of agonistic anti-OX40 mAbs and inhibitory anti-OX40L mAb to stimulate or inhibit OX40-OX40L interaction in vitro. The expression of NFATc1 mRNA and protein in lymphocytes of ApoE-/- mice was measured by Real Time PCR and flow cytometry, respectively. RESULTS: (1) After stimulating OX40-OX40L signal pathway, the expression of NFATc1 mRNA and protein in leukocytes of ApoE-/- mice was significantly increased, with maximal effect occurring at 20 µg/ml anti-OX40 mAb-stimulated, and peaked at 24 h at any concentration (P < 0.01). (2) Anti-OX40L mAb significantly suppressed the expression of NFATc1 in leukocytes of ApoE-/- mice, with maximal effect occurring at 20 µg/ml anti-OX40L mAb, and peaked at 24 h (P < 0.001). CONCLUSIONS: OX40-OX40L interaction can regulate the mRNA and protein expressions of NFATc1 in lymphocytes of ApoE-/- mice.

Positive correlation between CD137 expression and complex stenosis morphology in patients with acute coronary syndromes.

BACKGROUND: CD137, a member of the tumor necrosis factor receptor superfamily, has been reported to be expressed highly in patients with acute coronary syndromes. However, limited information is available on the relationship between CD137 expression and complex stenosis morphology in patients with acute coronary syndromes. METHODS: Our study included normal controls (n=50), patients with stable angina (SA) (n=80) and patients with acute coronary syndromes (ACS), including unstable angina (UA) (n=70) and acute myocardial infarction (AMI) (n=100). The expression of CD137 in peripheral monocytes was analyzed by flow cytometry. Serum soluble CD137 (sCD137), MMP-9 and MMP-3 levels were measured by enzyme-linked immunosorbent assay kit. All coronary stenoses with ≥50% diameter reduction were assessed by angiographic coronary stenosis morphology. RESULTS: Patients with ACS(n=170) showed a significant increase of CD137 [23.6±5.7 mean fluorescence intensity (MFI)] expression in peripheral monocytes compared with control (8.4±2.6 MFI) and SA group (7.9±2.1 MFI) (p<0.001). sCD137 also showed higher level in patients with ACS(30.2±8.7 ng/ml) than in control (6.2±1.8 ng/ml) and SA group (7.1±2.1 ng/ml) (p<0.001). Serum MMP-3 and MMP-9 in patients with ACS were 2-times greater than those in control and SA group. A positive correlation was found between MMP-9, MMP-3 and CD137 expression in peripheral monocytes as well as sCD137 levels. An obvious correlation was also observed between soluble or membrane-bound CD137 expression and complex coronary stenoses (r1=0.5548, r2=0.4652, and p<0.001). In the logistic regression model, the independent predictors of ACS were sCD137 (odds ratio 2.671, 95% CI 1.718-4.153, P=0.000), MMP-9 (1.431, 1.043-1.964, P=0.026) and MMP-3 (1.368, 1.038-1.817, P=0.018). CONCLUSION: Patients with ACS showed significantly positive correlation between CD137 expression and complex coronary stenosis morphology. We speculate that the increased CD137 expression might represent or reflect an instability of atherosclerotic plaques in patients with ACS.