Orphan nuclear receptor Nur77 Inhibits Oxidized LDL-induced differentiation of RAW264.7 murine macrophage cell line into dendritic like cells.

BACKGROUND: Nur77 is an orphan nuclear receptor expressed in human atheroma. In vascular cells in vitro, Nur77 expression is induced by pro-inflammatory factors, such as oxidized LDL (oxLDL). METHODS: We analyze the role of Nur77 in the oxLDL-induced differentiation of macrophages into dendritic cells (DC). The murine RAW264.7 macrophage cell line was stably transfected with expression plasmids encoding either GFP or GFP fusions with either full-length Nur77 (GFP-Nur77), Nur77 lacking the DNA binding domain (GFP-Nur77-ΔDBD) or Nur77 lacking the transactivation domain (GFP-Nur77-ΔTAD). RESULTS: GFP-Nur77 overexpression significantly suppressed the effect of oxLDL treatment on DC morphologic changes, expression of DC maturation markers, endocytic activity, allogeneic activation of T cell proliferation, and the activity and secretion of pro-inflammatory cytokines. Analysis of GFP-Nur77-ΔTAD and GFP-Nur77-ΔDBD indicated that the Nur77 DNA binding and transactivation domains were both required for this effect. GFP-Nur77-ΔDBD consistently had the opposite effect to GFP-Nur77, increasing DC-type differentiation in all assays. Interestingly, GFP-Nur77-ΔDBD protein was cytosolic, whereas GFP-Nur77 and GFP-Nur77-ΔTAD were both nuclear. CONCLUSIONS: These data show that GFP-Nur77 inhibited differentiation of oxLDL-treated macrophages into DC. The effects of Nur77 on the macrophage phenotype may involve changes in its subcellular distribution.

Endogenous renovascular hypertension combined with low shear stress induces plaque rupture in apolipoprotein E-deficient mice.

OBJECTIVE: The development of a murine model of spontaneous atherosclerotic plaque rupture with luminal thrombus. METHODS AND RESULTS: Combined partial ligation of the left renal artery and left common carotid artery in 8-week-old apolipoprotein E-deficient mice induced endogenous renovascular hypertension and local low oscillatory shear stress in the left common carotid artery. After 8 weeks, a fresh left common carotid artery lumen thrombus associated with severe plaque burden was found in 50% (10/20) of the mice. Histological analyses indicated that all left common carotid artery lesions had vulnerable features, and 50% (5/10) of the mice showed plaque rupture with a lumen thrombus. Multiple layers with layering discontinuity and intraplaque hemorrhages were found in 80% (8/10) of the mice. Further experiments showed that both increased blood pressure, and angiotensin-II contributed to plaque progression and vulnerability. Decreased intimal collagen associated with increased collagenase activity and matrix metalloproteinase expression also resulted in plaque disruption. CONCLUSIONS: We demonstrate a murine model of spontaneous plaque rupture with a high incidence of luminal thrombus. The model not only nicely recapitulates the pathophysiological processes of human plaque rupture but it is also simple, fast, and highly efficient to generate.

Atorvastatin suppresses inflammatory response induced by oxLDL through inhibition of ERK phosphorylation, IκBα degradation, and COX-2 expression in murine macrophages.

Macrophages crosstalk with oxidized low-density lipoprotein (oxLDL), play a critical role in the initiation, progression, and subsequently stability of atherosclerotic plaques. Statins, inhibitors of HMG CoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase, reduce the expression of inflammatory proteins in addition to their lipid-lowering action. However, the effect and detailed anti-inflammation mechanisms of statins in macrophages induced by oxLDL remain unclearly. In the present study, we investigated the effect of atorvastatin on inflammatory response upon oxLDL stimulation in murine macrophages and analyzed the underlying mechanisms. Tumor necrosis factor (TNF)α and monocyte chemoattractant protein-1 (MCP-1) mRNA levels were assayed by real-time PCR. The expression of cyclooxygenases-2 (COX-2) was detected by real-time PCR and Western blotting. While mitogen-activated protein kinase (MAPK) phosphorylation and IκBα degradation were determined by Western blotting. Our results showed that exposure of RAW264.7 cells to oxLDL, substantially changed the morphology of the cells and increased TNFα and MCP-1 secretion. While pretreatment with atorvastatin resulted in a significant inhibition of oxLDL-induced morphological alteration and inflammatory cytokines expression in a dose-dependent fashion. Further investigation of the molecular mechanism revealed that oxLDL upregulated the transcription and protein expression of COX-2 in a time-dependent manner. Whereas, pretreatment with atorvastatin suppressed COX-2 expression, MAPK activation and IκBα degradation. Thus, we conclude that the anti-inflammatory effect of atorvastatin is mediated through the inhibition of proinflammatory COX-2. Furthermore, suppression of ERK phosphorylation and IκBα degradation is involved in this regulation. Our findings provide a novel evidence that statins suppress inflammatory response, exert its anti-atherogenic actions via against inflammation beyond cholesterol-lowing effect.

Atorvastatin suppresses oxidized LDL-induced dendritic cell-like differentiation of RAW264.7 cells regulated by the p38 MAPK pathway.

Dendritic cells (DCs) are the most potent professional antigen-presenting cells and are involved in the initiation and progression of atherosclerosis. Recent data suggest that mature macrophages differentiate into dendritic-like cells when exposed to oxidized low-density lipoprotein (oxLDL). The purpose of the present study was to determine the effect of atorvastatin on the differentiation of macrophages to DCs and the molecular mechanisms of this transition. Mouse macrophage-like RAW264.7 cell was differentiated into a dendritic-like phenotype by incubation with oxLDL in the absence or presence of atorvastatin. The results showed that atorvastatin suppressed DC-like morphologic changes in vitro as assessed by decreased expression of DC maturation markers (CD83, CD11c, CD86, major histocompatibility complex class II, and CD1d). Atorvastatin also inhibited other oxLDL-induced functional changes including endocytic activity, ability to induce T cell proliferation, and cytokine secretion. Western blot analysis showed that oxLDL treatment of RAW264.7 cells induced phosphorylation of p38 mitogen-activated protein kinase (MAPK). However, blocking p38 MAPK with SB203580 significantly downregulated the expression of DC maturation markers, accompanied by decreased cytokine secretion. The findings of the present work demonstrate that that atorvastatin suppresses the oxLDL-induced DC-like differentiation of RAW264.7 cells by inactivating the p38 MAPK signaling pathway.

Pharmacoinvasive therapy for ST elevation myocardial infarction in China: a pilot study.

Most patients with acute ST-elevation myocardial infarction (STEMI) cannot receive timely primary percutaneous coronary intervention (PCI) because of lack of facilities or delays in patient transfer or catheterization team mobilization. In these patients, early routine post-thrombolysis PCI might be a reasonable, useful strategy. This study investigated feasibility and safety of early PCI after successful half-dose alteplase reperfusion in a Chinese population. Patients with STEMI received half-dose alteplase if expected time delay to PCI was ≥90 min. Patients who reached clinical criteria of successful thrombolysis reperfusion were recommended to undergo diagnostic angiography within 3-24 h after thrombolysis. Patients with residual stenosis ≥70% in the infarct-related artery underwent PCI, regardless of flow or patency status. Epicardial arterial flow was assessed using thrombolysis in myocardial infarction (TIMI) flow grade and TIMI frame count (CTFC). Myocardial perfusion was assessed using myocardial blush grade (MBG) and TIMI myocardial perfusion frame count (TMPFC). Forty-nine patients were enrolled and underwent diagnostic angiography 3-11.3 h (median 6.5 h) after thrombolysis. Forty-six patients underwent PCI. No procedure-related complications occurred, except two patients who had no reflow after PCI. Twenty-two (47.8%) patients had TIMI grade 3 flow before PCI and 33 (71.7%) after PCI. CTFC was significantly improved after PCI (48.5 ± 32.1 vs. 37.9 ± 25.6, P = 0.01). MBG and TMPFC exhibited a similar improving trend after PCI, and the best myocardial perfusion tended to be achieved 3-12 h after lysis. During the 30-day follow-up, there were two deaths. The composite end point of death, cardiogenic shock, heart failure, reinfarction, and recurrent ischemia occurred in four patients. TIMI minor bleeding occurred in four patients. No TIMI major bleeding and stroke occurred. Early routine PCI after half-dose alteplase thrombolysis in Chinese population appears feasible. A larger clinical trial should be designed to further elucidate its efficacy and safety. Early PCI after thrombolysis in STEMI: The EARLY-PCI pilot feasibility study, ChiCTR-TNC-11001363.

Statins for the prevention of contrast-induced nephropathy: a systematic review and meta-analysis.

BACKGROUND: Retrospective and prospective studies have demonstrated that statins have a protective effect in preventing contrast-induced nephropathy (CIN), but there are currently no established guidelines for statin timing or dosage. A systematic review and meta-analysis was performed to determine whether statin administration is protective and the magnitude of their effect. METHODS: We searched MEDLINE, EMBASE, Cochrane Library, CNKI and ISI Proceedings for cohort studies comparing the CIN incidence in a chronic statin pretreatment group and a statin-naïve group, as well as for randomized controlled trials (RCTs) comparing short-term high-dose to short-term low-dose statin treatment or placebo. CIN was defined as an increase in serum creatinine >25% or 0.5 mg/dl (44.2 µmol/l). Qualitative analysis of cohort studies and quantitative analysis of RCTs to estimate pooled risk ratios were performed. RESULTS: Among 6 cohort studies, 4 showed chronic statin pretreatment had a preventive effect against CIN. From 6 RCTs, 1,194 patients were included in the meta-analysis. Under the fixed-effects model, a nonsignificant protective trend toward decreased incidence of CIN with periprocedural short-term high-dose statin treatment was seen (RR: 0.70; 95% CI: 0.48-1.02). CONCLUSION: Current data are not conclusive to whether statins are protective for CIN due to the inherent limitations of the included studies. In the future, large well-designed studies are needed to address the effect of this drug and its longer-term clinical outcomes.

Comprehensive Analysis of N6-Methyladenosine RNA Methylation Regulators Expression Identify Distinct Molecular Subtypes of Myocardial Infarction.

Background: Myocardial infarction (MI) is one of the leading threats to human health. N6-methyladenosine (m6A) modification, as a pivotal regulator of messenger RNA stability, protein expression, and cellular processes, exhibits important roles in the development of cardiac remodeling and cardiomyocyte contractile function. Methods: The expression levels of m6A regulators were analyzed using the GSE5406 database. We analyzed genome-wide association study data and single-cell sequencing data to confirm the functional importance of m6A regulators in MI. Three molecular subtypes with different clinical characteristics were established to tailor treatment strategies for patients with MI. We applied pathway analysis and differentially expressed gene (DEG) analysis to study the changes in gene expression and identified four common DEGs. Furthermore, we constructed the protein-protein interaction network and confirmed several hub genes in three clusters of MI. To lucubrate the potential functions, we performed a ClueGO analysis of these hub networks. Results: In this study, we identified that the levels of FTO, YTHDF3, ZC3H13, and WTAP were dramatically differently expressed in MI tissues compared with controls. Bioinformatics analysis showed that DEGs in MI were significantly related to modulating calcium signaling and chemokine signaling, and m6A regulators were related to regulating glucose measurement and elevated blood glucose levels. Furthermore, genome-wide association study data analysis showed that WTAP single-nucleotide polymorphism was significantly related to the progression of MI. In addition, single-cell sequencing found that WTAP is widely expressed in the heart tissues. Moreover, we conducted consensus clustering for MI in view of the dysregulated m6A regulators' expression in MI. According to the expression levels, we found MI patients could be clustered into three subtypes. Pathway analysis showed the DEGs among different clusters in MI were assigned to HIF-1, IL-17, MAPK, PI3K-Akt signaling pathways, etc. The module analysis detected several genes, including BAG2, BAG3, MMP2, etc. We also found that MI-related network was significantly related to positive and negative regulation of angiogenesis and response to heat. The hub networks in MI clusters were significantly related to antigen processing and ubiquitin-mediated proteolysis, RNA splicing, and stability, indicating that these processes may contribute to the development of MI. Conclusion: Collectively, our study could provide more information for understanding the roles of m6A in MI, which may provide a novel insight into identifying biomarkers for MI treatment and diagnosis.

Integrative Analysis of Bulk and Single-Cell RNA Sequencing Data Reveals Cell Types Involved in Heart Failure.

Owing to the high mortality rates of heart failure (HF), a more detailed description of the HF becomes extremely urgent. Since the pathogenesis of HF remain elusive, a thorough identification of the genetic factors will provide novel insights into the molecular basis of this cardiac dysfunction. In our research, we performed publicly available transcriptome profiling datasets, including non-failure (NF), dilated cardiomyopathy (DCM) and ischemic cardiomyopathy (ICM) hearts tissues. Through principal component analysis (PCA), gene differential expression analysis, gene set enrichment analysis (GSEA), and gene Set Variation Analysis (GSVA), we figured out the candidate genes noticeably altered in HF, the specific biomarkers of endothelial cell (EC) and cardiac fibrosis, then validated the differences of the inflammation-related cell adhesion molecules (CAMs), extracellular matrix (ECM) genes, and immune responses. Taken together, our results suggested the EC and fibroblast could be activated in response to HF. DCM and ICM had both commonality and specificity in the pathogenesis of HF. Higher inflammation in ICM might related to autocrine CCL3/CCL4-CCR5 interaction induced chemokine signaling activation. Furthermore, the activities of neutrophil and macrophage were higher in ICM than DCM. These findings identified features of the landscape of previously underestimated cellular, transcriptomic heterogeneity between ICM and DCM.

Nuclear receptor Nur77 suppresses inflammatory response dependent on COX-2 in macrophages induced by oxLDL.

Oxidized low-density lipoprotein (oxLDL) cross-talks with macrophages, and both play a crucial role in the initiation and progression of atherosclerosis. Orphan nuclear receptor Nur77 is potently induced in macrophages by diverse stimuli, suggesting that it may be a key regulator of inflammation in vascular cells. The detailed mechanism of Nur77 activation and subsequent function in macrophages induced by oxLDL remains unclearly. In this study, we demonstrated that Nur77 is upregulated in a dose and time-dependent fashion by oxLDL stimulation in murine macrophages, as detected by real-time PCR and Western blotting. OxLDL activated the phosphorylation ERK1/2 and p38 MAPK, inhibition of p38 MAPK but not ERK1/2 attenuated Nur77 expression. Importantly, overexpression of Nur77 suppressed oxLDL-induced proinflammatory cytokines and chemokines secretion including tumor necrosis factor (TNF)alpha and monocyte chemoattractant protein-1(MCP-1). While knockdown Nur77 expression by specific small interfering RNA (siRNA) resulted in the enhancement of the secretion. Furthermore, exposure of macrophages to oxLDL significantly upregulated cyclooxygenase-2(COX-2) expression. However, this could be markedly inhibited by Nur77 overexpression. Also, Nur77 siRNA increased oxLDL-induced COX-2 expression and 6-mercaptopurine (6-MP) attenuated the increase. The results indicated that Nur77 is induced by oxLDL via p38 MAPK signal pathway and subsequently protects against inflammation by the inhibition of proinflammatory COX-2 pathway in activated macrophages. Specifically modifying transcription activity of Nur77 may represent a potential molecular target for the prevention and treatment of atherosclerosis.

The cannabinoid WIN55,212-2 protects against oxidized LDL-induced inflammatory response in murine macrophages.

The endocannabinoid system has recently been attracted interest for its anti-inflammatory and anti-oxidative properties. In this study, we investigated the role of the endocannabinoid system in regulating the oxidized low-density lipoprotein (oxLDL)-induced inflammatory response in macrophages. RAW264.7 mouse macrophages and peritoneal macrophages isolated from Sprague-Dawley (SD) rats were exposed to oxLDL with or without the synthetic cannabinoid WIN55,212-2. To assess the inflammatory response, reactive oxygen species (ROS) and tumor necrosis factor alpha (TNF- alpha) levels were determined, and activation of the mitogen-activated protein kinase (MAPK) and nuclear factor (NF)-kappa B signaling pathways were assessed. We observed that: i) oxLDL strongly induced ROS generation and TNF- alpha secretion in murine macrophages; ii) oxLDL-induced TNF- alpha and ROS levels could be lowered considerably by WIN55,212-2 via inhibition of MAPK (ERK1/2) signaling and NF-kappa B activity; and iii) the effects of WIN55212-2 were attenuated by the selective CB2 receptor antagonist AM630. These results demonstrate the involvement of the endocannabinoid system in regulating the oxLDL-induced inflammatory response in macrophages, and indicate that the CB2 receptor may offer a novel pharmaceutical target for treating atherosclerosis.

Retinoid X receptor agonists inhibit phorbol-12-myristate-13-acetate (PMA)-induced differentiation of monocytic THP-1 cells into macrophages.

Monocyte/macrophage differentiation is an essential process during atherosclerosis development. The retinoid X receptor (RXR) is a member of the nuclear hormone receptor superfamily, which plays an important regulatory role in many metabolic disorders, including atherosclerosis. The purpose of this study was to investigate the effect of RXR agonist on monocyte/macrophage differentiation in vitro. The THP-1 cell line was differentiated into a macrophage-like phenotype by incubation with phorbol-12-myristate-13-acetate (PMA) in the presence or absence of RXR agonist. The viability of adherent differentiated THP-1 cells was determined by MTT assay. Macrophage surface marker CD11b and CD36 was analyzed by flow cytometry. Phagocytosis was measured by fluorescence-labeled latex beads. The production of Cytokine Tunlornecrosisfactor-alpha (TNF-alpha), Interlaken-12p70 (IL-12p70), and Matrix metalloproteinase-9 (MMP-9), each of which was analyzed by ELISA. In the presence of the RXR agonists 9-cis retinoic acid or SR11237, PMA-induced THP-1 cells became less adherent, showed decreased macrophage-like morphological changes, decreased cell surface antigen CD11b and CD36 expression, and down regulated the phagocytosis of latex beads and the production of TNF-alpha and MMP-9. These data suggest that RXR agonists inhibit PMA-induced THP-1 cell differentiation into macrophage-like cells, which may be helpful in understanding the anti-atherosclerotic effect of RXR and its agonists.

Moringa oleifera seeds mitigate myocardial injury and prevent ventricular failure induced by myocardial infarction.

Moringa oleifera (MOI), an edible plant in the family of Moringaceae, has been used as food and medicine in many Asian countries. MOI exhibits neuroprotective, antioxidant, anti-inflammatory, and hypoglycemic functions. However, whether MOI seeds play a significant role in ischemic heart diseases has not been investigated. In this study, we found MOI seeds could improve the 28-day survival rate and the cardiac functions of myocardial infarction (MI) mice, with significantly increased ejection fraction and fractional shortening by day 28 post-MI. Correspondingly, the infarctional areas of heart were markedly decreased. Mechanistically, MOI seeds inhibited MI-induced apoptosis and repressed the degree of cardiac fibrosis. Further mechanistic studies indicated cardioprotective the effects of MOI seeds mainly via the suppression of oxidative and nitrosative stress. Taken together, our work suggested a beneficial role of MOI seeds in MI-induced myocardial damage and cardiac remodeling by suppressing cardiomyocyte apoptosis and reducing collagen production, highlighting a promising therapeutic strategy for MI.

Salvianolic Acid B Improves Postresuscitation Myocardial and Cerebral Outcomes in a Murine Model of Cardiac Arrest: Involvement of Nrf2 Signaling Pathway.

Survival and outcome of cardiac arrest (CA) are dismal despite improvements in cardiopulmonary resuscitation (CPR). Salvianolic acid B (Sal B), extracted from Salvia miltiorrhiza, has been investigated for its cardioprotective properties in cardiac remodeling and ischemic heart disease, but less is known about its role in CA. The aim of this study was to learn whether Sal B improves cardiac and neurologic outcomes after CA/CPR in mice. Female C57BL/6 mice were subjected to eight minutes of CA induced by an intravenous injection of potassium chloride (KCl), followed by CPR. After 30 seconds of CPR, mice were blindly randomized to receive either Sal B (20 mg/kg) or vehicle (normal saline) intravenously. Hemodynamic variables and indices of left ventricular function were determined before CA and within three hours after CPR, the early postresuscitation period. Sal B administration resulted in a remarkable decrease in the time required for the return of spontaneous circulation (ROSC) in animals that successfully resuscitated compared to the vehicle-treated mice. Myocardial performance, including cardiac output and left ventricular systolic (dp/dtmax) and diastolic (dp/dtmin) function, was clearly ameliorated within three hours of ROSC in the Sal B-treated mice. Moreover, Sal B inhibited CA/CPR-induced cardiomyocyte apoptosis and preserved mitochondrial morphology and function. Mechanistically, Sal B dramatically promoted Nrf2 nuclear translocation through the downregulation of Keap1, which resulted in the expression of antioxidant enzymes, including HO-1 and NQO1, thereby counteracted the oxidative damage in response to CA/CPR. The aforementioned antiapoptotic and antioxidant effects of Sal B were impaired in the setting of gene silencing of Nrf2 with siRNA in vitro model. These improvements were associated with better neurological function and increased survival rate (75% vs. 40%, p < 0.05) up to 72 hours postresuscitation. Our findings suggest that the administration of Sal B improved cardiac function and neurological outcomes in a murine model of CA via activating the Nrf2 antioxidant signaling pathway, which may represent a novel therapeutic strategy for the treatment of CA.

[Nuclear receptor Nur77 inhibits oxidized low density lipoprotein induced lipid loading in macrophages].

OBJECTIVE: To observe the effect of Nur77 on lipid loading in macrophages exposed to 40 microg/ml oxidized low density lipoprotein (ox-LDL). METHODS: Stable RAW264.7 strain expressing green fluorescent protein (GFP) or GFP-Nur77 was established by G418 screening after transfection with corresponding plasmids and identified by Western blot. After 24 h stimulation with ox-LDL, intracellular lipid loading of each strain was observed by Oil Red O dyeing, and the intracellular cholesterol level was measured by liquid chromatographic-mass spectrometry (LC-MS). The transcriptional changes of CD36 and ABCA1 were monitored by Real Time Quantitative-PCR, while the expressions of these two proteins were assayed by flow cytometry and Western blot, respectively. RESULTS: After 24 h stimulation with ox-LDL, intracellular total cholesterol and esterified cholesterol concentration in GFP-Nur77-RAW264.7 were significantly dropped by 26.15% and 30.93% respectively (P < 0.05 vs. GFP-RAW264.7). The transcription and expression of ABCA1 in GFP-Nur77-RAW264.7 were significantly increased while the transcription and expression of CD36 were significantly reduced (all P < 0.05 vs. GFP-RAW264.7). CONCLUSION: Orphan nuclear receptor Nur77 reduced ox-LDL induced intracellular lipid loading in macrophages by inhibiting lipid influx and enhancing lipid efflux.

[Effect of retinoid X receptor activation on oxidized low-density lipoprotein induced cell differentiation of murine macrophage cell line into dendritic like cells].

OBJECTIVE: To investigate the effect and related mechanism of retinoid X receptor (RXR) activation on oxidized low-density lipoprotein (ox-LDL) induced differentiation of macrophage into dendritic cell. METHODS: RAW264.7 murine macrophage cell line was cultured with ox-LDL for 48 h in the absence and presence of RXR activator 9-cisRA or SR11237. Cell morphology was observed by phase contrast microscope and cell surface markers involved in dendritic cell immune maturation and activation was analyzed by FACS. Cellular reactive oxygen species production was detected by CM-H2DCFDA fluorescent probe. RESULTS: ox-LDL-treated RAW264.7 murine macrophage cell line differentiated into dendritic like cells after 48 h and cell surface markers CD40, CD86, CD83, MHC Class II and CD1d were upregulated. These changes could be attenuated by cotreatment with 9-cisRA or SR11237. Upregulated cell surface markers CD40, CD86, CD83, MHC Class II and CD1d by ox-LDL were decreased about 47%, 43%, 48%, 32% and 17% respectively by 9-cisRA and 38%, 38%, 46%, 36% and 32% respectively by SR11237. The effect of 9-cisRA and SR11237 was dose dependent. Cellular reactive oxygen species were significantly increased in ox-LDL-treated RAW264.7 cells (MFI 38.24 +/- 4.20 vs. 4.46 +/- 0.39, P < 0.05) and which was significantly reduced by 9-cisRA (10(-7) mol/L) and SR11237 (10(-6) mol/L) to 12.60 +/- 1.52 and 17.89 +/- 1.91 respectively (all P < 0.05). CONCLUSION: RXR activation partly inhibits the differentiation of ox-LDL induced macrophage into dendritic cell by reducing oxidative stress injury.

Comparison of Effects of Different Statins on Contrast-Induced Acute Kidney Injury in Rats: Histopathological and Biochemical Findings.

Statins are a promising new strategy to prevent contrast-induced acute kidney injury (CI-AKI). In this study we compared the ameliorative effect of different statins in a rat model of CI-AKI. Sprague-Dawley rats were divided into five groups: control group; CI-AKI group; CI-AKI + rosuvastatin group (10 mg/kg/day); CI-AKI + simvastatin group (80 mg/kg/day); and CI-AKI + atorvastatin group (20 mg/kg/day). CI-AKI was induced by dehydration for 72 hours, followed by furosemide intramuscular injection 20 minutes before low-osmolar contrast media (CM) intravenous injection. Statins were administered by oral gavage once daily for 3 consecutive days before CM injection and once 4 hours after CM injection. Rats were sacrificed 24 hours after CM injection, and renal function, kidney histopathology, nitric oxide (NO) metabolites, and markers of oxidative stress, inflammation, and apoptosis were evaluated. The results showed that atorvastatin and rosuvastatin but not simvastatin ameliorated CM-induced serum creatinine elevation and histopathological alterations. Atorvastatin and rosuvastatin showed similar effectiveness against CM-induced oxidative stress, but simvastatin was less effective. Atorvastatin was most effective against NO system dysfunction and cell apoptosis, whereas rosuvastatin was most effective against inflammation. Our findings indicate that statins exhibit differential effects in preventing CI-AKI when given at equivalent lipid-lowering doses.

Use of Both Serum Cystatin C and Creatinine as Diagnostic Criteria for Contrast-Induced Acute Kidney Injury and Its Clinical Implications.

BACKGROUND: Contrast-induced acute kidney injury (CI-AKI) was traditionally defined as an increase in serum creatinine (sCr) after contrast media exposure. Recently, serum cystatin C (sCyC) has been proposed as an alternative to detect acute changes in renal function. The clinical implications of combining sCyC and sCr to diagnose CI-AKI remain unknown. METHODS AND RESULTS: One thousand seventy-one consecutive patients undergoing coronary angiography/intervention were prospectively enrolled. SCyC and sCr were assessed at baseline and 24 to 48 hours after contrast media exposure. CI-AKI determined by sCr (CI-AKIsCr) was defined as an sCr increase greater than 0.3 mg/dL or 50% from baseline. Major adverse events at 12 months were assessed. CI-AKIsCr developed in 25 patients (2.3%). Twelve-month follow-up was available for 1063 patients; major adverse events occurred in 61 patients (5.7%). By receiver operating characteristic curve analysis, an sCyC increase of greater than 15% was the optimal cutoff for CI-AKIsCr detection, which occurred in 187 patients (17.4%). To evaluate the use of both sCyC and sCr as CI-AKI diagnostic criteria, we stratified patients into 3 groups: no CI-AKI, CI-AKI detected by a single marker, and CI-AKI detected by both markers. Multivariable logistic regression revealed that the predictability of major adverse events increased in a stepwise fashion in the 3 groups (no-CI-AKI group as the reference, CI-AKI detected by a single marker: odds ratio=2.25, 95% CI: 1.24-4.10, P<0.01; CI-AKI detected by both markers: odds ratio=10.00, 95% CI: 3.13-31.91, P<0.001). CONCLUSIONS: Combining sCyC and sCr to diagnose CI-AKI would be beneficial for risk stratification and prognosis in patients after contrast media exposure.

Circulating MicroRNA-188, -30a, and -30e as Early Biomarkers for Contrast-Induced Acute Kidney Injury.

BACKGROUND: Contrast-induced acute kidney injury (CI-AKI) is typically defined by an increase in serum creatinine after intravascular administration of contrast medium. Because creatinine is an unreliable indicator of acute changes in kidney function, we assessed whether circulating microRNAs (miRNAs) could serve as biomarkers for early detection of CI-AKI. METHODS AND RESULTS: Using a rat model of CI-AKI, we first evaluated the miRNA profile of rat plasma and kidney. Three miRNA species with >1.5-fold increase in plasma samples of CI-AKI rats, including miRNA-188, miRNA-30a, and miRNA-30e, were selected as candidate miRNAs. Quantitative real-time polymerase chain reaction showed that these candidate miRNAs peaked in concentration around 4 hours after contrast medium exposure and were relatively renal-specific. We compared the plasma levels of these candidate miRNAs in 71 patients who underwent coronary angiography or percutaneous coronary intervention and developed CI-AKI with those of 71 matched controls. The plasma levels of the 3 candidate miRNAs were significantly elevated in the CI-AKI group as compared to the control group. Receiver operating characteristic analysis showed that these miRNAs significantly distinguished patients with CI-AKI from those without CI-AKI. MiRNA composites were highly accurate for CI-AKI prediction, as shown in maximized specificity by treble-positive miRNA composite or maximized Youden index by any-positive miRNA composite. Moreover, the selected miRNAs changes were associated with Mehran Risk Scores. CONCLUSIONS: Plasma levels of candidate miRNAs significantly distinguished patients with CI-AKI from those without CI-AKI. Thus, miRNAs are potential biomarkers for early detection of CI-AKI.

[Effect of danshensu, protocatechualdehyde and danshen injection on calcium ion concentration in cytoplasm of human erythrocytes].

OBJECTIVE: To study the predominant calcium-antagonist components of Danshen injection. METHOD: The effects of danshensu, protocatechualdehyde and Danshen injection on calcium concentration in cytoplasm of erythrocytes were examined in vitro by the fluorescent Ca+ -chelator fura-2. RESULT: Either DS182 or PCAD can decrease in dose-dependent cytosolic free calcium concentration in human erythrocytes. They had additive effect when mixed, which was similar to Danshen injection. CONCLUSION: DS182 and PCAD may be predominant calcium-antagonist components of Danshen injection.

Oxidized low-density lipoprotein induces differentiation of RAW264.7 murine macrophage cell line into dendritic-like cells.

Dendtritic cells (DCs) are potent antigen-presenting cells and have an important role in the pathogenesis of atherosclerosis. Recent data suggests oxidized low-density lipoprotein (oxLDL) promotes the transition of a differentiating monocyte to a mature dendritic cell. In this study, we examined whether oxLDL could induce the differentiation of mature macrophages into DCs. After 48 h treatment with oxLDL, RAW264.7 cells increased in cell size and exhibited dendritic morphology. At the optimal oxLDL dose (10 microg/ml), approximately 74% of RAW264.7 cells differentiated into dendritic-like cells. Flow cytometric analysis detected dendritic cell surface markers (CD83, CD40, CD86, MHC Class II, and CD1d), and their expression increased in a dose- and time-dependent manner. Moreover, oxLDL-treated RAW264.7 cells showed functional changes including reduced endocytic activity, increased allostimulatory activity, and IL-12 production. The findings of the present work demonstrate that RAW264.7 cells, incubated with oxLDL, acquire some dendritic cell features.