Association between hepatitis B and E virus infection and hepatocellular carcinoma risk.

The role of hepatitis E virus (HEV) in developing hepatocellular carcinoma (HCC) is unclear. Our study aimed to investigate the role of HE infection in HCC development and the effect of hepatitis B virus (HBV) and HEV coinfection on HCC risk. A hospital-based case-control study was conducted. A total of 474 eligible HCC cases and 586 control patients were successfully recruited. The fasting venous blood was collected from the patients at the first visited to hospital and HBV infection and HEV infection were examined within 5 days. Crude and adjusted odd ratios (ORs) with 95% confidence interval (95% CI) were estimated by using logistic regression model. HBV infection (OR: 63.10, 95% CI: 42.02-97.26) rather than HEV infection (OR: 1.08, 95% CI: 0.721-1.65) was associated with an increased risk of HCC after adjustment for confounders. The association between HBV infection and HCC risk was more remarkable in male (OR: 72.61, 95% CI: 45.10-121.38) than in female (OR: 61.89, 95% CI: 25.74-169.26). In comparison with patients who infected with neither HEV nor HBV, those who infected with only HBV (OR: 69.62, 95% CI: 40.90-123.52) and who coinfected with HEV and HBV (OR: 67.48, 95% CI:37.23-128.19) were significantly associated with an increased risk after adjustment for potential confounders. The results showed that HBV infection rather than HEV infection was associated with an increased risk of HCC, and the HEV infection may alleviate the promoting impact of HBV on HCC development.

Comparison of Ca2+ Handling for the Regulation of Vasoconstriction between Rat Coronary and Renal Arteries.

BACKGROUND: Ca2+ plays an important role in the regulation of vasoconstriction. Ca2+ signaling is regulated by a number of Ca2+-handling proteins. However, whether differences in Ca2+ handling affect the regulation of vasoconstriction in different arteries remains elusive. OBJECTIVE: To determine whether differences in Ca2+ handling affect the response to vasoconstrictors in different arteries. METHODS: Arterial ring contraction was measured using a Multi Myograph System. Vascular smooth muscle cells (VSMCs) were digested with type 2 collagenase in DMEM, then intracellular calcium concentration was measured with the Ca2+ probe fluo-4/AM in the isolated cells. Calcium-related proteins were assayed by Western blotting. RESULTS: Phenylephrine did not induce -coronary arterial contraction. There were differences in -5-hydroxytryptamine, 9,11-dideoxy-11a,9a-epoxymethano-prostaglandin F2a, and endothelin 1-induced vasoconstriction in different solutions between coronary and renal arteries. Vasoconstrictions in the presence of Bay K8644 were stronger in coronary than in renal arteries. Store-operated calcium (SOC) channels could mediate Ca2+ influx in VSMCs of both groups. SOC channels did not participate in the contraction of coronary arteries. In addition, there were significant differences in the expressions of receptors and ion channels between the two groups. CONCLUSIONS: Ca2+ handling contributed to the different responses to vasoconstrictors between coronary and renal arteries.

Mechanisms of U46619-induced contraction in mouse intrarenal artery.

Thromboxane A2 (TXA2 ) has been implicated in the pathogenesis of vascular complications, but the underlying mechanism remains unclear. The contraction of renal arterial rings in mice was measured by a Multi Myograph System. The intracellular calcium concentration ([Ca2+ ]i ) in vascular smooth muscle cells (VSMCs) was obtained by using a fluo-4/AM dye and a confocal laser scanning microscopy. The results show that the U46619-induced vasoconstriction of renal artery was completely blocked by a TXA2 receptor antagonist GR32191, significantly inhibited by a selective phospholipase C (PI-PLC) inhibitor U73122 at 10 µmol/L and partially inhibited by a Phosphatidylcholine - specific phospholipase C (PC-PLC) inhibitor D609 at 50 µmol/L. Moreover, the U46619-induced vasoconstriction was inhibited by a general protein kinase C (PKC) inhibitor chelerythrine at 10 µmol/L, and a selective PKCδ inhibitor rottlerin at 10 µmol/L. In addition, the PKC-induced vasoconstriction was partially inhibited by a Rho-kinase inhibitor Y-27632 at 10 µmol/L and was further completely inhibited together with a putative IP3 receptor antagonist and store-operated Ca2+ (SOC) entry inhibitor 2-APB at 100 µmol/L. On the other hand, U46619-induced vasoconstriction was partially inhibited by L-type calcium channel (Cav1.2) inhibitor nifedipine at 1 µmol/L and 2-APB at 50 and 100 µmol/L. Last, U46619-induced vasoconstriction was partially inhibited by a cell membrane Ca2+ activated C1- channel blocker 5-Nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) at 50 and 100 µmol/L. Our results suggest that the U46619-induced contraction of mouse intrarenal arteries is mediated by Cav1.2 and SOC channel, through the activation of thromboxane-prostanoid receptors and its downstream signaling pathway.

Involvement of Orai1 in tunicamycin-induced endothelial dysfunction.

Endoplasmic reticulum (ER) stress is mediated by disturbance of Ca2+ homeostasis. The store-operated calcium (SOC) channel is the primary Ca2+ channel in non-excitable cells, but its participation in agent-induced ER stress is not clear. In this study, the effects of tunicamycin on Ca2+ influx in human umbilical vein endothelial cells (HUVECs) were observed with the fluorescent probe Fluo-4 AM. The effect of tunicamycin on the expression of the unfolded protein response (UPR)-related proteins BiP and CHOP was assayed by western blotting with or without inhibition of Orai1. Tunicamycin induced endothelial dysfunction by activating ER stress. Orai1 expression and the influx of extracellular Ca2+ in HUVECs were both upregulated during ER stress. The SOC channel inhibitor SKF96365 reversed tunicamycin-induced endothelial cell dysfunction by inhibiting ER stress. Regulation of tunicamycin-induced ER stress by Orai1 indicates that modification of Orai1 activity may have therapeutic value for conditions with ER stress-induced endothelial dysfunction.

CDK6 mediates the effect of attenuation of miR-1 on provoking cardiomyocyte hypertrophy.

MicroRNA-1 (miR-1) is approved involved in cardiac hypertrophy, but the underlying molecular mechanisms of miR-1 in cardiac hypertrophy are not well elucidated. The present study aimed to investigate the potential role of miR-1 in modulating CDKs-Rb pathway during cardiomyocyte hypertrophy. A rat model of hypertrophy was established with abdominal aortic constriction, and a cell model of hypertrophy was also achieved based on PE-promoted neonatal rat ventricular cardiomyocytes (NRVCs). We demonstrated that miR-1 expression was markedly decreased in hypertrophic myocardium and hypertrophic cardiomyocytes. Dual luciferase reporter assays revealed that miR-1 interacted with the 3'UTR of CDK6, and miR-1 was verified to inhibit CDK6 expression at the posttranscriptional level. CDK6 protein expression was observed increased in hypertrophic myocardium and hypertrophic cardiomyocytes. Morover, miR-1 mimic, in parallel to CDK6 siRNA, could inhibit PE-induced hypertrophy of NRVCs, with decreases in cell size, newly transcribed RNA, expressions of ANF and ß-MHC, and the phosphorylated pRb. Taken together, our results reveal that derepression of CDK6 and activation of Rb pathway contributes to the effect of attenuation of miR-1 on provoking cardiomyocyte hypertrophy.

Left ventricular deformation associated with cardiomyocyte Ca(2+) transients delay in early stage of low-dose of STZ and high-fat diet induced type 2 diabetic rats.

BACKGROUND: In the early stage of diabetes, the cardiac ejection fraction is preserved, despite the existence of the subclinical cardiac dysfunction to some extent. However, the detailed phenotype of this dysfunction and the underlying mechanism remain unclear. To improve our understanding of this issue, we used low-dose STZ and high-fat diet to induce type 2 diabetic models in rats. The effects and the mechanism associated with the early stages of the disease were analyzed. METHODS: The type 2 diabetic mellitus (T2DM) in SD rats were induced through 30 mg/kg STZ and high-fat diet. Two-dimensional spackle-tracking echocardiography (STE) and the dobutamine test were performed to examine the cardiac function. Calcium transients of left ventricular myocytes were detected and the related intracellular signalling factors were analyzed by western blotting. RESULTS: After 6-weeks, T2DM rats in left ventricular (LV) diastole showed decreased global and segment strain(S) levels (P < 0.05), both in the radial and circumferential directions. Strain rate (Sr) abatement occurred in three segments in the radial and circumferential directions (P < 0.05), and the radial global Sr also decreased (P < 0.05). In the systolic LV, radial Sr was reduced, except the segment of the anterior septum, and the Sr of the lateral wall and post septum decreased in the circumferential direction (P < 0.05). Conventional M-mode echocardiography failed to detect significant alterations of cardiac performance between the two groups even after 12 weeks, and the decreased ejection fraction (EF%), fractional shortening (FS%) and end-systolic diameters (ESD) could be detected only under stress conditions induced by dobutamine (P < 0.05). In terms of calcium transients in cardiac myocytes, the Tpeak in model rats at 6 weeks was not affected, while the Tdecay1/2 was higher than that of the controls (P < 0.05), and both showed a dose-dependent delay after isoproterenol treatment (P < 0.05). Western blot analysis showed that in 6-week T2DM rats, myocardial p-PLB expression was elevated, whereas p-CaMKII, p-AMPK and Sirt1 were significantly down-regulated (P < 0.05). CONCLUSION: A rat model of T2DM was established by low dose STZ and a high-fat diet. LV deformation was observed in the early stages of T2DM in association with the delay of Ca(2+) transients in cardiomyocytes due to the decreased phosphorylation of CaMKII. Myocardial metabolism remodeling might contribute to the early LV function and calcium transportation abnormalities.

Attenuation of microRNA-16 derepresses the cyclins D1, D2 and E1 to provoke cardiomyocyte hypertrophy.

Cyclins/retinoblastoma protein (pRb) pathway participates in cardiomyocyte hypertrophy. MicroRNAs (miRNAs), the endogenous small non-coding RNAs, were recognized to play significant roles in cardiac hypertrophy. But, it remains unknown whether cyclin/Rb pathway is modulated by miRNAs during cardiac hypertrophy. This study investigates the potential role of microRNA-16 (miR-16) in modulating cyclin/Rb pathway during cardiomyocyte hypertrophy. An animal model of hypertrophy was established in a rat with abdominal aortic constriction (AAC), and in a mouse with transverse aortic constriction (TAC) and in a mouse with subcutaneous injection of phenylephrine (PE) respectively. In addition, a cell model of hypertrophy was also achieved based on PE-promoted neonatal rat ventricular cardiomyocyte and based on Ang-II-induced neonatal mouse ventricular cardiomyocyte respectively. We demonstrated that miR-16 expression was markedly decreased in hypertrophic myocardium and hypertrophic cardiomyocytes in rats and mice. Overexpression of miR-16 suppressed rat cardiac hypertrophy and hypertrophic phenotype of cultured cardiomyocytes, and inhibition of miR-16 induced a hypertrophic phenotype in cardiomyocytes. Expressions of cyclins D1, D2 and E1, and the phosphorylated pRb were increased in hypertrophic myocardium and hypertrophic cardiomyocytes, but could be reversed by enforced expression of miR-16. Cyclins D1, D2 and E1, not pRb, were further validated to be modulated post-transcriptionally by miR-16. In addition, the signal transducer and activator of transcription-3 and c-Myc were activated during myocardial hypertrophy, and inhibitions of them prevented miR-16 attenuation. Therefore, attenuation of miR-16 provoke cardiomyocyte hypertrophy via derepressing the cyclins D1, D2 and E1, and activating cyclin/Rb pathway, revealing that miR-16 might be a target to manage cardiac hypertrophy.

Population pharmacokinetics and safety of eptifibatide in healthy Chinese volunteers and simulations on the dose regimens approved for a Western population.

OBJECTIVE: This study was designed to evaluate the pharmacokinetics (PK) and safety of eptifibatide in healthy Chinese volunteers and provide information for the further study in the Chinese population. METHODS: 30 healthy volunteers (15 male) were enrolled in the study and divided into three dose groups (45 µg x kg⁻¹, 90 µg x kg⁻¹, and 180 µg x kg⁻¹). Plasma and urine samples were drawn after one single-bolus administration and measured by LC-MS/MS. The plasma and urine data were analyzed simultaneously by the population approach using the NONMEM software and evaluated by the visual predicted check (VPC) and bootstraping. The PK profiles of dose regimens approved for a Western population in the Chinese population were simulated. RESULTS: A two-compartment model adequately described the PK profiles of eptifibatide. The clearance (CL) and the distribution volume (V1) of the central compartment were 0.128 L x h⁻¹ x kg⁻¹ and 0.175 L x kg⁻¹, respectively. The clearance (Q) and V2of the peripheral compartment were 0.0988 L x h⁻¹ x kg⁻¹ and 0.147 L x kg⁻¹, respectively. The elimination fraction from plasma to urine (F0) was 17.2%. No covariates were found to have a significant effect. Inter-individual variabilites were all within 33.9%. The VPC plots and bootstrap results indicated good precision and prediction of the model. The simulations of the approved regimens in the Chinese population showed much lower steady-state concentrations than the target concentration obtained from the Western clinical trials. No severe safety events were found in this study. CONCLUSIONS: The PK model of eptifibatide was established and could provide PK information for further studies in the Chinese population.

Fn14 promotes differentiation of human mesenchymal stem cells into heart valvular interstitial cells by phenotypic characterization.

Despite the fact that tissue engineered heart valves (TEHV) hold great promise for heart valve disease treatment, one of the challenges is to find suitable seeding cells. Bone marrow derived mesenchymal stem cells (MSCs) were considered to be one of the best seed cell sources. In this study we propose a novel approach to promote stem cell differentiation into the seed cells of TEHV, valvular interstitial cells (VICs). Newly induced MSCs (iMSCs) were created from a co-culture niche in which healthy human donor derived MSCs were co-cultured with cardiac fibroblasts (H9C2 cell line). Then iMSCs were transfected with either a mock vector (iMSCs(mock) ) as controls or with a vector that overexpresses thefibroblast inducible factor 14 (Fn14) gene (iMSCs(Fn14) ). Immunofluorescence staining was performed to assay VIC differentiation. Western blot analysis was performed to analyze the involved signaling pathway. The results demonstrate that the expression of α-smooth muscle actin (SMA) was significantly higher in iMSCs(Fn14) as compared with iMSC(mock) , and MSC, and also had higher co-alignment of α-actinin and stress fiber (F-actin) in bundles. Additionally, increased biosynthesis of extracellular matrix (ECM) proteins including collagen I, collagen III, and fibronection were observed in iMSCs(Fn14) in comparison with iMSCs(mock) . These data observed in iMSCs(Fn14) were in accordance with VIC phenotype from normal heart valves. In addition, the PI3K/Akt signaling pathway was activated in iMSCs(Fn14) which allowed higher Akt phosphorylation (p-Akt) levels and SMA levels, whereas, it was attenuated by LY294002 (PI3K/Akt inhibitor). These new findings of the effect of Fn14 on VIC-like cell differentiation may provide a novel therapeutic strategy for heart valve disease treatment.

The caspase-8 shRNA-modified mesenchymal stem cells improve the function of infarcted heart.

The beneficial effects of mesenchymal stem cells (MSCs) in cardiac cell therapy are greatly limited due to poor survival after transplantation into ischemic hearts. Here, we investigated whether caspase 8 small hairpin RNA (shRNA) modification enhance human MSCs (hMSCs) survival and improve infarcted heart function. Recombinant adenovirus encoding pre-miRNA-155-designed caspase 8 shRNA was prepared to inhibit caspase 8 expression in hMSCs. The effect of caspase 8 shRNA modification on protecting hMSCs from apoptosis under the conditions of serum deprivation and hypoxia was tested by Annexin V/PI staining and caspase 8 activity assay. The caspase 8 shRNA-modified and superparamagnetic iron oxide (SPIO)-labeled hMSCs were injected into the border zone of the infarcted region of rat heart. Echocardiography and Masson trichrome staining were performed to assess heart function and cardiac fibrosis. Our results showed that adenovirus-mediated caspase 8 shRNA could efficiently inhibit caspase 8 expression in hMSCs. Knock-down of caspase 8 expression lead to inhibition of hMSCs apoptosis, reduction of caspase 8 activity and up-regulations of HGF, IGF-1 and Bcl-2. Transplantation of caspase 8 shRNA-modified hMSCs could significantly improve infracted heart function, attenuate cardiac fibrosis. Consistently, the rate of cardiomyocyte apoptosis and caspase 8 activity were significantly decreased, and the survival rate of transplanted hMSCs was markedly elevated in the myocardium receiving caspase 8 shRNA-modified hMSCs transplantation. Together, our findings implicated the therapeutic potential of caspase 8 shRNA-modified hMSCs in improving the infarcted heart function.

Activated hedgehog gene pattern correlates with dismal clinical outcome and tumor microenvironment heterogeneity in hepatocellular carcinoma.

Background: Activation of the Hedgehog signaling pathway is linked to the initiation and development of human hepatocellular carcinoma (HCC). However, its impact on clinical outcomes and the HCC microenvironment remains unclear. Methods: We performed comprehensive analyses of Hedgehog pathway genes in a large cohort of HCC patients. Specifically, we utilized univariate Cox regression analysis to identify Hedgehog genes linked to overall survival, and the LASSO algorithm was used to construct a Hedgehog-related gene pattern. We subsequently examined the correlation between the Hedgehog pattern and the HCC microenvironment employing the CIBERSORT and ssGSEA algorithms. Furthermore, Tumor Immune Dysfunction and Exclusion (TIDE) algorithm and the anti-PD-L1 treatment dataset (IMvigor210) are used to evaluate the clinical response of the Hedgehog pattern in predicting immune checkpoint inhibitors. Results: We found that the Hedgehog activation score (HHAS), a prognostic score based on 11 Hedgehog genes, was significantly associated with HCC patient survival. Patients exhibiting high HHAS experienced markedly reduced survival rates compared to those with low HHAS, and HHAS emerged as an independent prognostic factor for HCC. Functional enrichment analysis unveiled the association of the HHAS phenotype with functions related to the immune system, and further investigation demonstrated that HCC patients exhibiting low HHAS displayed elevated levels of anti-tumor immune activation in CD8+ T cells, while high HHAS were linked to immune escape phenotypes and increased infiltration of immune suppressive cells. In addition, in the Immune Checkpoint Inhibitor (ICI) cohort of IMvigor210, patients with higher HHAS had worse ICI treatment outcomes and shortened survival time, indicating that the HHAS is a useful indicator for predicting patient response to immunotherapy. Conclusions: In summary, our study offers valuable insights for advancing research on Hedgehog and its impact on tumor immunity, which provides an opportunity to optimize prognosis and immune therapy for HCC.

Mechanism of macrophage migration inhibitory factor-induced decrease of T-type Ca(2+) channel current in atrium-derived cells.

The T-type Ca(2+) current (I(Ca,T)) plays an important role in the pathogenesis of atrial fibrillation (AF). The present study sought to investigate the role of macrophage migration inhibitory factor (MIF), a pleiotropic cytokine, in the regulation of T-type Ca(2+) channels (TCCs) in atrial myocytes. We used the whole-cell voltage-clamp technique and biochemical assays to study the regulation and expression of I(Ca,T) in atrial myocytes. Gene levels of the α1G and α1H subunit of TCCs were decreased in human atrial tissue of patients with AF. In cultured atrium-derived myocytes (HL-1 cells), mouse recombinant MIF (20 or 40 nm, 24 h) suppressed peak I(Ca,T) in a concentration-dependent manner, impaired the voltage-dependent activation of I(Ca,T) and downregulated TCC α1G and α1H mRNA. The Src inhibitors genistein and PP1 significantly enhanced I(Ca,T). The reduction of I(Ca,T) and TCC subunit mRNA induced by recombinant MIF could be reversed by genistein and PP1. The TCC α1G associated with Src in HL-1 cells and mouse cardiomycytes. Macrophage migration inhibitory factor is involved in the pathogenesis of AF, probably by decreasing the T-type calcium current in atrium-derived myocytes through impairment of channel function and activation of c-Src kinases, representing a potential pathogenic mechanism in atrial fibrillation.

Decreased expression of DAB2IP in pancreatic cancer with wild-type KRAS.

BACKGROUND: KRAS mutation plays an important role in the pathogenesis of pancreatic cancer. However, the role of wild-type KRAS in the progression of pancreatic cancer remains unknown. The present study was to investigate the expression of the Ras GTPase activating protein (DAB2IP) in pancreatic cancer and its clinical significance. METHODS: The expression of DAB2IP in pancreatic cancer cell lines and normal human pancreatic ductal epithelial cells was analyzed by Western blotting and real-time quantitative reverse transcription-PCR (qRT-PCR). The KRAS mutational types of pancreatic cancer tissues obtained from pancreatic cancer patients (n=20) were also analyzed. Subsequently, DAB2IP expression was detected in pancreatic cancer tissues, adjacent and normal pancreatic tissues (n=2) by immunohistochemistry, and the relationship between DAB2IP expression and the clinical characteristics of patients was evaluated. RESULTS: Western blotting and qRT-PCR results showed that DAB2IP expression in pancreatic cancer cells with wild-type KRAS was lower than that in those with mutation-type KRAS and normal human pancreatic ductal epithelial cells (P<0.05). Immunohistochemistry showed that DAB2IP expression was lower in pancreatic cancer tissues than that in adjacent and normal pancreatic tissues (Z=-4.000, P=0.000). DAB2IP expression was lower in pancreatic cancer patients with the wild-type KRAS gene than that in those with KRAS mutations (WilcoxonW=35.000, P=0.042). Furthermore, DAB2IP expression in patients with perineurial invasion was lower than that in those without invasion (WilcoxonW=71.500, P=0.028). DAB2IP expression was lower in patients with more advanced stage than that in those with early clinical stage (WilcoxonW=54.000, P=0.002). CONCLUSIONS: DAB2IP expression was reduced in patients with pancreatic cancer compared with those with no cancer. DAB2IP expression was correlated with the KRAS gene, perineurial invasion and clinical stage of the disease. Our data indicated that DAP2IP expression can be used as a potential prognostic indicator and a promising molecular target for therapeutic intervention in patients with pancreatic cancer.

Hepatitis E Virus Seroprevalence Indicated a Significantly Increased Risk Selectively in Patients with Gastric Cancer among 17 Common Malignancies.

Background: The impact of hepatitis E virus (HEV) infection on cancer development has been poorly investigated. This study aimed to explore the relationship between HEV seroprevalence and cancer risks and to identify high cancer risk subgroups in HEV-exposed populations. Methods: HEV seroprevalence status was determined in cancer and non-cancer subjects. Logistic regression and sensitivity analyses were used to assess the relationship between HEV antibody seropositivity and cancer risk for 17 cancer types. Additionally, interaction analyses were applied to interpret the association of HEV seroprevalence and other cancer risk factors. Results: Of the enrolled 4948 cancer and 4948 non-cancer subjects, cancer subjects had a higher anti-HEV seropositivity than non-cancer subjects (46.36% vs. 32.50%, p < 0.01). However, this divergency varied in degrees across different cancer types. Additionally, HEV seroprevalence was associated with cancer risk in young males (OR: 1.64, 95% CI: 1.19−2.27, p < 0.01). Remarkably, a significant association between HEV seroprevalence and cancer risk was observed only in gastric cancer patients (OR: 1.82, 95% CI: 1.07−3.09, p = 0.03). Conclusions: HEV seroprevalence was associated with cancer risk selectively in gastric cancer patients and young males, suggesting that cancer screening, particularly gastric cancer, should be regularly performed in young males with a history of HEV exposure.

Integrating interacting drugs and genetic variations to improve the predictability of warfarin maintenance dose in Chinese patients.

OBJECTIVE: Compared with genetic factors, drug interactions are largely unexplored in pharmacogenetic studies. This study sought to systematically investigate the effects of VKORC1, STX4A, CYP2C9, CYP4F2, CYP3A4, and GGCX gene polymorphisms and interacting drugs on warfarin maintenance dose. METHODS: A retrospective study of 845 Chinese patients after heart valve replacement receiving long-term warfarin maintenance therapy was conducted. Thirteen polymorphisms in the six genes were genotyped, and 36 drugs that may interact with warfarin were investigated. RESULTS: Single-nucleotide polymorphism association analysis showed that VKORC1, CYP2C9 and CYP4F2 variations were highly associated with the warfarin maintenance dose. Among 36 drugs that may interact with warfarin, fluconazole, amiodarone, and omeprazole were associated with the requirement for 45.8, 16.7, and 16.7% lower median warfarin dose (all P<0.05 with a false discovery rate <0.05). The final pharmacogenetic equation explained 43.65% of interindividual variation of warfarin maintenance dose with age, body surface area, VKORC1 g.3588G>A, CYP2C9*3, CYP4F2 c.1297G>A, amiodarone, fluconazole, and diltiazem accounting for 1.97, 2.74, 24.12, 3.94, 1.64, 5.92, 2.47, and 0.84% of variation. CONCLUSION: The present study indicated that VKORC1, CYP4F2, and CYP2C9 genotypes and interacting drugs had a significant impact on the warfarin maintenance dose in Chinese patients with heart valve replacement and demonstrated that integrating interacting drugs can largely improve the predictability of the dose algorithm.

Induced bone marrow mesenchymal stem cells improve cardiac performance of infarcted rat hearts.

We investigated whether transplantation of bone marrow mesenchymal stem cells (BMSC) with induced BMSC (iBMSC) or uninduced BMSC (uBMSC) into the myocardium could improve the performance of post-infarcted rat hearts. BMSCs were specified by flowcytometry. IBMSCs were cocultured with rat cardiomyocyte before transplantation. Cells were injected into borders of cardiac scar tissue 1 week after experimental infarction. Cardiac performance was evaluated by echocardiography at 1, 2, and 4 weeks after cellular or PBS injection. Langendorff working-heart and histological studies were performed 4 weeks after treatment. Myogenesis was detected by quantitative PCR and immunofluorescence. Echocardiography showed a nearly normal ejection fraction (EF) in iBMSC-treated rats and all sham control rats but a lower EF in all PBS-treated animals. The iBMSC-treated heart, assessed by echocardiography, improved fractional shortening compared with PBS-treated hearts. The coronary flow (CF) was decreased obviously in PBS and uBMSC-treated groups, but recovered in iBMSC-treated heart at 4 weeks (P < 0.01). Immunofluorescent microscopy revealed co-localization of Superparamagnetic iron oxide (SPIO)-labeled transplanted cells with cardiac markers for cardiomyocytes, indicating regeneration of damaged myocardium. These data provide strong evidence that iBMSC implantation is of more potential to improve infarcted cardiac performance than uBMSC treatment. It will open new promising therapeutic opportunities for patients with post-infarction heart failure.

High levels of glucose induce "metabolic memory" in cardiomyocyte via epigenetic histone H3 lysine 9 methylation.

Diabetic patients continue to develop inflammation and cardiovascular complication even after achieving glycemic control, suggesting a "metabolic memory". Metabolic memory is a major challenge in the treatment of diabetic complication, and the mechanisms underlying metabolic memory are not clear. Recent studies suggest a link between chromatin histone methylation and metabolic memory. In this study, we tested whether histone 3 lysine-9 tri-methylation (H3K9me3), a key epigenetic chromatin marker, was involved in high glucose (HG)-induced inflammation and metabolic memory. Incubating cardiomyocyte cells in HG resulted in increased levels of inflammatory cytokine IL-6 mRNA when compared with myocytes incubated in normal culture media, whereas mannitol (osmotic control) has no effect. Chromatin immunoprecipitation (ChIP) assays showed that H3K9me3 levels were significantly decreased at the promoters of IL-6. Immunoblotting demonstrated that protein levels of the H3K9me3 methyltransferase, Suv39h1, were also reduced after HG treatment. HG-induced apoptosis, mitochondrial dysfunction and cytochrome-c release were reversible. However, the effects of HG on the expression of IL-6 and the levels of H3K9me3 were irreversible after the removal of HG from the culture. These results suggest that HG-induced sustained inflammatory phenotype and epigenetic histone modification, rather than HG-induced mitochondrial dysfunction and apoptosis, are main mechanisms responsible for metabolic memory. In conclusion, our data demonstrate that HG increases expression of inflammatory cytokine and decreases the levels of histone-3 methylation at the cytokine promoter, and suggest that modulating histone 3 methylation and inflammatory cytokine expression may be a useful strategy to prevent metabolic memory and cardiomyopathy in diabetic patients.

Transcription factor Ap-1 mediates proangiogenic MIF expression in human endothelial cells exposed to Angiotensin II.

Macrophage migration inhibitory factor (MIF) is an inflammatory cytokine associated with the atherosclerotic process and atherosclerotic plaque stability. MIF was shown to be highly expressed in advanced atherosclerotic lesions. Neutralizing MIF with a blocking antibody induced a regression of established atherosclerotic lesions. In this study, we investigated the mechanism underlying the proangiogenic effect of MIF in human umbilical vein endothelial cells (HUVECs). We showed that MIF induced the expression of angiogenesis-related genes in HUVECs. We also showed that MIF induced tube formation of HUVECs in vitro and in vivo. Angiotensin II (Ang II) could specifically up-regulate MIF expression in HUVECs. Using a luciferase reporter assay, we demonstrated that the AP-1 response element in the 5'-UTR of the MIF gene played a role in Ang II-induced MIF expression. Small hairpin RNA (shRNA) targeting c-Jun, a component of AP-1, and the AP-1 inhibitor CHX both efficiently inhibited MIF expression. The consistent result of electrophoretic mobility shift assay (EMSA) showed that Ang II specifically increased AP-1 activation in HUVECs. Our results suggest that AP-1 mediates Ang II-induced MIF expression which contributes to atherosclerotic plaque destabilization in human endothelial cells.

The influence of genetic polymorphisms and interacting drugs on initial response to warfarin in Chinese patients with heart valve replacement.

PURPOSE: Compared with genetic factors, drug interactions were largely unexplored in warfarin pharmacogenetic studies. This study sought to systematically investigate the effects of genetic polymorphisms of VKORC1, STX4A, CYP2C9, CYP3A4, and GGCX and interacting drugs on the initial responses to warfarin in Chinese patients with heart valve replacement (HVR). METHODS: A retrospective study was conducted in 809 patients starting warfarin therapy after HVR. The relationships between 12 polymorphisms plus 47 drugs and primary outcomes of the time to the first international normalized ratio (INR) ≥ 1.8 and the time to the first INR > 3.5 and the secondary outcomes of the proportion of time INR < 1.8, the proportion of time INR > 3.5, and the daily warfarin dose in the first 28 days after the initiation of warfarin treatment were analyzed. RESULTS: Genetic polymorphisms and interacting drugs could significantly affect the primary and secondary outcomes. The time to the first INR ≥ 1.8 was significantly influenced by the body surface area (BSA), VKORC1 g.3588G > A allele, and CYP2C9*3 allele, with hazard ratio (HR; 95% confidence interval [CI]) of 0.34 (0.17-0.66), 2.71 (2.2-3.35) and 1.43 (1.07-1.93) respectively. The time to the first INR > 3.5 was affected not only by BSA, VKORC1 g.3588G > A allele, and CYP2C9*3 allele with HR (95%CI) of 0.26 (0.07-0.99), 2.76 (1.61-4.72), and 3.09 (2.02-4.74) respectively, but also by age and interacting drugs, including fluconazole, amiodarone, and simvastatin with HR (95%CI) of 1.02 (1.01-1.04), 2.66 (1.16-6.08), 1.78 (1.17-2.73), and 5.33 (1.67-16.96) respectively. CONCLUSIONS: Not only VKORC1 and CYP2C9 genotypes, but also interacting drugs, had a significant impact on the variability of the initial response to warfarin.

High levels of glucose induce apoptosis in cardiomyocyte via epigenetic regulation of the insulin-like growth factor receptor.

Diabetic hyperglycemia result in cardiovascular complications, but the mechanisms by which high levels of glucose (HG) cause diabetic cardiomyopathy are not known. We investigate whether HG-induced repression of insulin-like growth factor 1 receptor (IGF-1R) mediated by epigenetic modifications is one potential mechanism. We found that HG resulted in decreased IGF-1 receptor (IGF-1R) mRNA levels, and IGF-1R protein when compared with H9C2 rat cardiomyocyte cells incubated in normal glucose. HG also induced apoptosis of H9C2 cells. The effects of HG on reduced expression of IGF-1R and increased apoptosis were blocked by silencing p53 with small interference RNA but not by non-targeting scrambled siRNA. Moreover, HG negatively regulated IGF-1R promoter activity as determined by ChIP analysis, which was dependent on p53 since siRNA-p53 attenuated the effects of HG on IGF-1R promoter activity. HG also increased the association of p53 with histone deacetylase 1 (HDAC1), and decreased the association of acetylated histone-4 with the IGF-1R promoter. Furthermore, HDAC inhibitor relieved the repression of IGF-1R following HG state. These results suggest that HG-induced repression of IGF-1R is mediated by the association of p53 with the IGF-1R promoter, and by the subsequent enhanced recruitment of chromatin-modifying proteins, such as HDAC1, to the IGF-1R promoter-p53 complex. In conclusion, our data demonstrate that HG decreases expression of IGF-1R and decreases the association of acetylated histone-4 with the IGF-1R promoter. These studies may help delineate the complex pathways regulating diabetic cardiomyopathy, and have implications for the development of novel therapeutic strategies to prevent diabetic cardiomyopathy by epigenetic regulation of IGF-1R.