Correlation between the Serum Platelet-Derived Growth Factor, Angiopoietin-1, and Severity of Coronary Heart Disease.

BACKGROUND: The expression of the platelet-derived growth factor (PDGF), angiopoietin-1 (Ang-1) in patients with coronary artery disease of different studies was inconsistent. This study was to investigate the expression of the PDGF and Ang-1 in peripheral blood and coronary artery in patients with acute coronary syndrome (ACS) and the relationship between the expression of the PDGF and Ang-1 and the severity of coronary artery disease. METHODS: A total of 81 patients with acute coronary syndrome undergoing coronary angiography were enrolled from September 2012 to December 2013. Patients with ACS included 61 patients with acute myocardial infarction (AMI group) and 20 patients with unstable angina pectoris (UAP group). The 29 patients who were hospitalized for chest pain undergoing coronary angiography without stenosis and with TIMI level 3 blood flow were selected as the control group. During coronary arteriography (CAG) or percutaneous coronary intervention (PCI), blood in the peripheral artery and in the local coronary artery was collected from all the patients. Serum PDGF and Ang-1 levels were measured by ELISA. We calculated the Gensini score of each patient with CHD according to the result of CAG. Patients with ACS were followed up, and the major adverse cardiovascular and cerebrovascular adverse events were recorded. RESULTS: In peripheral blood, the concentration of the PDGF was significantly elevated in the ACS group than that of the control group. The level of the PDGF in the AMI group was significantly higher than that in the UAP group. In coronary artery blood, the level of the PDGF in the ACS group was significantly higher than that of the UAP group. There was no significant difference in the concentration of Ang-1 in peripheral blood between patients with coronary heart disease and the control group. The concentration of Ang-1 in the coronary artery was significantly lower than that in peripheral blood. The coronary Ang-1 concentrations in the ACS group were significantly higher than those in the UAP group. The concentrations of the PDGF and Ang-1 in peripheral and coronary artery blood were positively correlated with the severity of coronary lesions. Patients with MACCE had higher PDGF and Ang-1 levels in the coronary sinus. CONCLUSION: The serum PDGF concentration in patients with acute coronary syndrome was significantly increased, especially in the local coronary artery. The serum Ang-1 in the coronary artery was significantly increased in patients with acute myocardial infarction and was related to the degree of coronary artery stenosis. Coronary sinus PDGF and Ang-1 levels can reflect the severity of lesions in patients with acute coronary syndrome.

The Ethical Dilemma of Truth-Telling in Healthcare in China.

Truth-telling is often regarded as a challenge in Chinese medical practices given the amount of clinical and ethical controversies it may raise. This study sets to collect and synthesize relevant ethical evidence of the current situation in mainland China, thereby providing corresponding guidance for medical practices. This study looks into the ethical issues on the basis of the philosophy of deontology and utilitarianism and the ethical principles of veracity, autonomy, beneficence, and nonmaleficence. Chinese philosophy, context and culture are also discussed to provide some suggestions for decision-making about disclosure in a medical setting. This study holds that, in order to respect the basic rights to which critically ill patients are entitled, decisions regarding truth-telling and their implementation should be carried out with thorough consideration, which can be achieved by critical thinking, well-developed and effective communication skills, the consideration of cultural context, an understanding of individual differences, and compliance with relevant laws and regulations.

The evolution and characterization of influenza A(H7N9) virus under the selective pressure of peramivir.

Human infection with H7N9 virus has provoked global public health concern due to the substantial morbidity and mortality. Neuraminidase inhibitors (NAIs) are used as first-line drugs to treat the infection. However, virus quasispecies can evolve rapidly under drug pressure, which may alter various biological characteristics of virus. Using an in vitro evolution platform and next-generation sequencing, we found the presence of peramivir led to changes to the dominant populations of the virus. Two important amino acid substitutions were identified in NA, I222T and H274Y, which caused reduced susceptibilities to oseltamivir or both oseltamivir and peramivir as confirmed by enzyme- and cell-based assays. The NA-H274Y variant showed decreased replicative fitness at the early stage of infection accompanied with impaired NA function. The quasispecies evolution of H7N9 virus and the potential emergence of these two variants should be closely monitored, which may guide the adjustment of antiviral strategies.

Catechin Attenuates Coronary Heart Disease in a Rat Model by Inhibiting Inflammation.

Accumulating evidence has established that systemic inflammation is an important pathophysiologic factor of coronary heart disease (CHD). In this study, we investigated whether catechin exerts anti-inflammatory function in CHD rats. CHD model of rats was established by high-fat diet feeding and pituitrin injection. The successful building of CHD model was confirmed using blood liquid biochemical analyzer. Additionally, the effects of catechin on CHD parameters and several inflammatory signaling were investigated. The levels of total cholesterol, high-density lipoprotein, low-density lipoprotein cholesterin, triglyceride and blood glucose were all significantly elevated in CHD rats compared to them in control rats, suggesting the successful establishment of CHD model. Administration of catechin attenuated CHD by reversing the levels of creatine kinase, creatine kinase-MB, lactate dehydrogenase, cardiac troponin (cTnT), ventricular ejection fraction (LVEF) and systolic internal diameter (LVIDs). Additionally, several inflammatory biomarkers or cytokines such as C-reactive protein, lipoprotein-associated phospholipase A2 (Lp-PLA2), interleukin (IL)-6 and tumor necrosis factor-alpha (TNF-α) were inhibited by catechin. In contrast to nuclear factor-kappa beta (NF-κB), several proteins involved in inflammation such as farnesoid X receptor, signal transducers and activators of transcription (STAT)-3 and protein kinase B (PKB/Akt) were all activated by catechin. Catechin could be used as a promising treatment for CHD based on its role in suppressing inflammation and balancing STAT-3 signaling.

Detection of influenza viruses by coupling multiplex reverse-transcription loop-mediated isothermal amplification with cascade invasive reaction using nanoparticles as a sensor.

Influenza virus infections represent a worldwide public health and economic problem due to the significant morbidity and mortality caused by seasonal epidemics and pandemics. Sensitive and convenient methodologies for detection of influenza viruses are essential for further disease control. Loop-mediated isothermal amplification (LAMP) is the most commonly used method of nucleic acid isothermal amplification. However, with regard to multiplex LAMP, differentiating the ladder-like LAMP products derived from multiple targets is still challenging today. The requirement of specialized instruments has further hindered the on-site application of multiplex LAMP. We have developed an integrated assay coupling multiplex reverse transcription LAMP with cascade invasive reaction using nanoparticles (mRT-LAMP-CIRN) as a sensor for the detection of three subtypes of influenza viruses: A/H1N1pdm09, A/H3 and influenza B. The analytic sensitivities of the mRT-LAMP-CIRN assay were 101 copies of RNA for both A/H1N1pdm09 and A/H3, and 102 copies of RNA for influenza B. This assay demonstrated highly specific detection of target viruses and could differentiate them from other genetically or clinically related viruses. Clinical specimen analysis showed the mRT-LAMP-CIRN assay had an overall sensitivity and specificity of 98.3% and 100%, respectively. In summary, the mRT-LAMP-CIRN assay is highly sensitive and specific, and can be used as a cost-saving and instrument-free method for the detection of influenza viruses, especially for on-site use.

[Association of solute-linked carrier family 26 member A3 gene polymorphisms with ulcerative colitis among Chinese patients].

OBJECTIVE: To assess the association of single nucleotide polymorphisms (SNPs) and haplotypes of solute-linked carrier family 26 member A3 (SLC26A3) gene with ulcerative colitis (UC) among Chinese patients. METHODS: For 416 UC patients and 584 controls, 5 SNPs of the SLC26A3 gene (rs17154444, rs7810937, rs7785539, rs2108225 and rs6951457) were determined with a SNaPshot method. Linkage disequilibrium (LD) and haplotype were analyzed for all subjects. RESULTS: The G allele and AG+GG genotype of rs2108225 were more prevalent in UC patients compared with the controls (65.14% vs. 58.65%, P=0.030; 87.02% vs. 81.85%, P=0.012, respectively). The C allele and TC+CC genotype of rs17154444 were more prevalent in patients with severe UC than in other patients (14.00% vs. 6.01%, P<0.01; 28.00% vs. 11.48%, all P<0.01). Similar conclusion may also be drawn for C allele and GC+CC genotype of rs7785539 (8.00% vs. 7.38%, P=0.011; 16.00% vs. 13.93%, P=0.017, respectively). The SNPs rs17154444, rs7810937, rs7785539 and rs2108225 were found to be in strong LD. Compared with the controls, the T-A-G-G haplotype was more prevalent in UC patients (62.60% vs. 58.20%, P=0.017), whereas the T-G-G-A haplotype was less common in UC patients (27.40% vs. 31.60%, P=0.041). CONCLUSION: Variations of the SLC26A3 rs2108225 may enhance the risk of UC. The rs17154444 and rs7785539 polymorphisms of the SLC26A3 gene are correlated with the severity of UC. The T-A-G-G haplotype formed by rs17154444, rs781093, rs7785539 and rs2108225 of the SLC26A3 gene may increase the risk for UC, whereas the T-G-G-A haplotype may decrease this risk.

Serum Cytokine Profile in Relation to the Severity of Coronary Artery Disease.

Objectives. To investigate the potential association of a set of serum cytokines with the severity of coronary artery disease (CAD). Methods. A total of 201 patients who underwent coronary angiography for chest discomfort were enrolled. The concentrations of serum IFN-γ, TNF-α, IL-2, IL-4, IL-6, IL-10, IL-9, and IL-17 were determined by xMAP multiplex technology. The CAD severity was assessed by Gensini score (GS). Results. The serum levels of TNF-α, IL-6, IL-9, IL-10, and IL-17 were significantly higher in high GS group (GS ≥ 38.5) than those in low GS group (GS < 38.5). Positive correlations were also found between these cytokines and the severity of CAD. After adjustment for other associated factors, three serum cytokines (IL-6, IL-9, and IL-17) and two clinical risk factors (creatinine and LDL-C) were identified as the independent predictors of increased severity of CAD. ROC curve analysis revealed that the logistic regression risk prediction model had a good performance on predicting CAD severity. Conclusions. Combinatorial analysis of serum cytokines (IL-6, IL-9, and IL-17) with clinical risk factors (creatinine and LDL-C) may contribute to the evaluation of the severity of CAD and may help guide the risk stratification of angina patients, especially in primary health facilities and in the catheter lab resource-limited settings.

[Analysis of single nucleotide polymorphisms and haplotypes of FCGR2A gene among patients with ulcerative colitis].

OBJECTIVE: To assess the association of several single nucleotide polymorphisms and haplotypes of the FCGR2A gene with ulcerative colitis (UC) among Chinese patients. METHODS: For 198 UC patients and 356 healthy controls, the alleles and genotypes of the FCGR2A gene (rs1801274, rs10800309 and rs6696854) were detected with a multiplex SNaPshot technique. All subjects were also subjected to linkage disequilibrium and haplotype analyses. RESULTS: The mutant homozygote (CC) of the FCGR2A gene rs1801274 polymorphism was less frequent among UC patients compared with the controls (5.56% vs. 11.80%, P=0.017, OR=0.440, 95%CI: 0.221-0.875). However, the allelic and genotypic distributions of other two SNPs did not differ significantly between the two groups (all P>0.05). Furthermore, no association of the three SNPs (rs1801274, rs10800309 and rs6696854) of the FCGR2A gene with the severity and location of the UC was found (all P>0.05). The three SNPs were shown to be in a strong linkage [rs1801274-rs10800309 (D'=0.863, r2=0.634); rs1801274-rs6696854 (D'=0.753, r2=0.546); rs10800309-rs6696854(D'=0.990, r2=0.802)]. Moreover, the frequency of T-A-T haplotype was higher among the UC patients compared with the controls (67.40% vs. 60.93%, P=0.032, OR=1.326, 95%CI: 1.024-1.717). CONCLUSION: Our findings suggested that the mutant homozygote (CC) of the FCGR2A gene (rs1801274) may have a protective role among Chinese patients with UC. Moreover, the T-A-T haplotype formed by rs1801274, rs10800309 and rs6696854 may confer a higher risk for UC.

[Association of inflammatory bowel disease with the polymorphisms and haplotypes of fucosyltransferase 3 gene].

OBJECTIVE: To assess the association of inflammatory bowel disease with polymorphisms and haplotypes of Fucosyltransferase 3 (FUT3) gene. METHODS: A total of 389 patients with ulcerative colitis (UC), 274 patients with Crohn's disease (CD), and 492 controls were collected. Three single nucleotide polymorphisms (SNPs) of the FUT3 gene (rs28362459, rs3745635 and rs3894326) were determined by direct sequencing. Linkage disequilibrium and haplotype analysis were performed using a Haploview 4.2 software. RESULTS: Compared with the controls, the allele and genotype distributions of FUT3 gene did not significantly differ between the UC and CD groups (all P>0.05). By stratified analysis, the mutant allele (A) and genotype (GA+AA) of the FUT3 gene (rs3745635) were significantly increased in the UC group with distal colitis compared with the controls (P<0.01, P<0.05, respectively). The mutant allele (G) and genotype (TG+GG) of the FUT3 gene (rs28362459) as well as the mutant allele (A) of FUT3(rs3745635) were significantly increased in patients with ileocolonic CD and ileal CD as compared with the controls (P<0.05, P<0.01, P<0.05, respectively). The frequency of mutant allele (G) of FUT3(rs28362459) was higher in stricturing CD patients than in the controls (P<0.05). In addition, the three polymorphic loci of FUT3 gene were shown in complete linkage disequilibrium [rs3894326/rs3745635 (D'=1.0, r2=0.017), rs3894326/rs28362459 (D'=0.937, r2=0.311), rs3745635/rs28362459 (D'=0.944, r2=0.448)]. However, the frequency of each haplotype was not significantly different between the UC and CD groups compared with the controls (all P>0.05). CONCLUSION: FUT3 (rs3745635) mutation may increase the risk of distal colitis. FUT3 (rs28362459 and rs3745635) mutations may engender the increased risk of ileocolonic and ileal CD. Moreover, FUT3 (rs28362459) polymorphism may influence the incidence of stricturing CD.

TAP1 I333V gene polymorphism and type 1 diabetes mellitus: a meta-analysis of 2248 cases.

Transporter associated with antigen processing 1 (TAP1) I333V gene polymorphism has been suggested to be associated with type 1 diabetes mellitus (T1DM) susceptibility. However, the results from individual studies are inconsistent. To explore the association of TAP1 I333V gene polymorphisms with T1DM, a meta-analysis involving 2246 cases from 13 individual studies was conducted. The pooled odd ratios (ORs) and their corresponding 95% confidence intervals (95% CIs) were evaluated by a fixed-effect model. A significant relationship was observed between TAP1 I333V gene polymorphism and T1DM in allelic (OR: 1.35, 95% CI: 1.08-1.68, P = 0.007), dominant (OR: 1.462, 95% CI: 1.094-1.955, P = 0.010), homozygous (OR: 1.725, 95% CI: 1.082-2.752, P = 0.022), heterozygous (OR: 1.430, 95% CI: 1.048-1.951, P = 0.024) and additive (OR: 1.348, 95% CI: 1.084-1.676, P = 0.007) genetic models. No significant association between TAP1 I333V gene polymorphism and T1DM was detected in a recessive genetic model (OR: 1.384, 95% CI: 0.743-2.579, P = 0.306) in the entire population, especially among Caucasians. No significant association between them was found in an Asian or African population. TAP1 I333V gene polymorphism was significantly associated with increased T1DM risk. V allele carriers might be predisposed to T1DM susceptibility.

Adrenergic regulation of the rapid component of delayed rectifier K+ currents in guinea pig cardiomyocytes.

BACKGROUND: Guinea pig ventricular cardiomyocytes display the rapid component of the delayed rectifier potassium current (Ikr) that contributes to ventricular repolarization and promotes stress-induced arrhythmias. Adrenergic stimulation favors ventricular arrhythmogenesis but its effects on Ikr are poorly understood. METHODS: Adrenergic modulation of Ikr was studied in isolated guinea pig ventricular cardiomyocytes using whole-cell patch clamping. RESULTS: We found that the Ikr amplitude was reduced to 0.66±0.02 and 0.62±0.03 in response to 0.1 µM phenylephrine (PE), an α1AR agonist, and 10 µM isoproterenol (ISO), a ßAR agonist, respectively. The effect of PE can be blocked by the selective α1A-adrenoceptor antagonist 5-methylurapidil, but not by the α1B-adrenoceptor antagonist chloroethylclonidine or α1D-adrenoceptor antagonist BMY7378. Additionally, the effect of ISO can be blocked by the ß1-selective AR antagonist CGP-20712A, but not by the ß2-selective AR antagonist ICI-118551. Although PE and ISO was continuously added to cells, ISO did not decrease the current to a greater extent when cells were first given PE. In addition, PE's effect on Ikr was suppressed by ß1AR stimulation. CONCLUSIONS: Ikr can by regulated by both the α1 and ß ARs system, and that in addition to direct regulation by each receptor system, crosstalk may exist between the two systems.

Serum microRNA expression profile as a biomarker for the diagnosis of pertussis.

Pertussis is a highly contagious, respiratory disease associated with substantial morbidity and mortality. A rapid and reliable diagnostic method is essential for appropriate treatment and prevention. Expression profiles of circulating microRNAs (miRNAs) have been proven as new non-invasive biomarkers for infectious diseases. We aimed to investigated the serum miRNA profile in pertussis patients and explored its potential as a novel diagnostic biomarker for pertussis. Among 664 different miRNAs analyzed using a miRNA array, 50 were overexpressed and 81 were underexpressed in the serum of pertussis patients. Expression levels of seven candidate miRNAs were further evaluated by real-time qRT-PCR. A panel of five miRNAs (miR-202, miR-342-5p, miR-206, miR-487b, miR-576-5p) was confirmed overexpressed in pertussis patients (p < 0.05). Risk score and receiver-operating characteristic (ROC) analysis showed that the area under the curve of the five-member miRNA profile was 0.980. At an optimal cutoff value (0.707), this panel of miRNAs yielded a sensitivity of 97.4 % and a specificity of 94.3 %. These data suggest that the five-member serum miRNA profile may serve as a new biomarker for pertussis diagnosis with high specificity and sensitivity.

Involvement of reductive stress in the cardiomyopathy in transgenic mice with cardiac-specific overexpression of heat shock protein 27.

Oxidative stress plays an important role in cardiac diseases, which has been well demonstrated, whereas the role of reductive stress has been poorly investigated. We and others have shown previously that heat shock protein 27 (Hsp27) plays a role as an antioxidant. To investigate whether overexpression of Hsp27 could lead to reductive stress and result in cardiomyopathy, we generated transgenic mice with different expression levels of Hsp27. We observed that transgenic mice with high levels of Hsp27 developed cardiomyopathy. The myopathic hearts were under reductive stress, which was evidenced by an increased ratio of reduced glutathione/oxidized glutathione and a decreased level of reactive oxygen species. In addition, upregulated glutathione peroxidase 1 and decreased iron content were revealed in the myopathic hearts. More importantly, inhibition of glutathione peroxidase 1 significantly attenuated the development of cardiomyopathy. The data indicate that the Hsp27-induced cardiomyopathy could be attributed to, at least in part, upregulation of glutathione peroxidase 1. Our findings suggest that reductive stress plays an important role in the development of cardiomyopathy and that Hsp27 may serve as a potential target for the treatment of patients with cardiomyopathy.

Cardiac-specific expression of heat shock protein 27 attenuated endotoxin-induced cardiac dysfunction and mortality in mice through a PI3K/Akt-dependent mechanism.

Cardiac dysfunction is a major consequence of septic shock and may be responsible for the high mortality of sepsis. We have reported that transgenic mice with cardiac-specific overexpression of heat shock protein 27 (Hsp27 Tg) exhibited the protection against doxorubicin-induced cardiac dysfunction. We hypothesized that overexpression of Hsp27 will attenuate cardiac dysfunction during endotoxemia. Hsp27 Tg and age-matched wild-type (WT) mice were injected with LPS. Cardiac function was evaluated by echocardiography, survival rate was carefully monitored, and activities of signaling pathways were determined by immunoblot. LPS administration significantly decreased cardiac function in WT mice. In Hsp27 Tg mice, LPS-induced cardiac dysfunction was significantly attenuated as evidenced by increased ejection fraction (27.3%) and fractional shortening (37.1%), respectively, compared with LPS-treated WT mice. Heat shock protein 27 Tg mice were more resistant to LPS-induced mortality than WT. The levels of phospho-Akt and phospho-glycogen synthase kinase 3beta (phospho-GSK-3beta) in the myocardium were significantly increased in Hsp27 Tg mice compared with WT after LPS administration. Nuclear factor kappaB-binding activity was significantly decreased in Hsp27 Tg mice compared with WT mice after LPS challenge. Similar results were observed in in vitro studies using Hsp27-transfected rat cardiomyoblasts. Importantly, phosphoinositide 3-kinase inhibition abolished the protective effect of Hsp27 in LPS-induced cardiac dysfunction and mortality of endotoxemia. Our results suggest that Hsp27 plays an important role in attenuation of cardiac dysfunction and mortality in endotoxemia and that the mechanisms of the protection may involve activation of the PI3K/Akt signaling pathway.

[Heat shock protein 27 attenuated doxorubicin-induced myocardial damage by reducing cardiomyocyte apoptosis, mitochondria damage and protein carbonylation].

OBJECTIVE: Oxidative stress and apoptosis play a critical role in the pathogenesis of congestive heart failure (CHF) induced by doxorubicin (Dox) or ischemia/reperfusion. Heat shock protein 27 (Hsp27) could reduce oxidative stress induced apoptosis in various cell types in vitro and attenuate ischemia/reperfusion induced cardiac dysfunction in isolated perfused mouse heart. In this study, we investigated the impact of Hsp27 overexpression on oxidative stress and apoptosis in Dox-induced mice cardiac dysfunction model. METHODS: Both Hsp27 transgenic mice (TG) and wild type littermates (WT) received a single dosage of Dox (25 mg/kg IP) or saline. On day 3, histological examinations (Paraffin section and HE staining, mitochondria ultrastructure), in situ cardiomyocytes apoptosis assay (TUNEL, immunohistochemistry against alpha-actinin for cardiomyocytes, hoechst33342 for nuclei staining), protein oxidative damage assay (immunoblot against DNP) were performed on cardiac tissue samples. Pleural effusion and histological changes of heart and lung were examined in dead mice. RESULTS: (1) Significant pleural effusion, pulmonary congestion, alveoli collapse and extravasated red blood cells were observed in all died mice. (2) Pronounced cardiomyocyte damages and inhomogeneous HE staining were observed in almost all dead mice except for one TG mouse died at day 4 which showed homogeneous HE staining and only slightly cardiomyocyte damages. (3) Cardiac fibrosis was presented in WT mice but not in TG mice. (4) Dox-induced cardiomyocyte apoptosis and protein carbonylation were significantly attenuated in TG mice compared those in WT mice. (5) Severity of Dox-induced mitochondria damage including increased density, swollen cristae and loss of cristae definition was significantly reduced in TG mice compared to that in WT mice were seen in all the examined myocytes of the LV myocardium samples of Dox-treated mice. CONCLUSION: Hsp27 could attenuate Dox-induced myocardial damage by reducing cardiomyocyte apoptosis, mitochondria damage and protein carbonylation.

[Overexpression of heat shock protein 27 reduces mortality and attenuates cardiac dysfunction induced by doxorubicin in a transgenic mouse model].

OBJECTIVE: To observe the effects of heat shock protein 27 (Hsp27) overexpression on doxorubicin (Dox) induced mortality and cardiac dysfunction in a transgenic (TG) mouse model. METHODS: A linear DNA constituted of alpha-myosin heavy chain (alpha-MHC) promoter, human Hsp27cDNA and poly A was microinjected into fertilized eggs to generate transgenic mice and mice containing the transgene were identified by polymerase chain reaction and independent transgenic lines were established. Following successful transmission, tissues including heart, lung, liver, brain, skeleton muscle, spleen and kidney were screened by Western blot to confirm the cardiac specific expression of the transgene. TG and wild type littermates (WT) received a single dosage of Dox injection (25 mg/kg IP) or saline injection and observed for 5 days. Mice mortality was noticed and left ventricular (LV) hemodynamics were measured at day 5 in surviving mice. Cardiomyocyte apoptosis was evaluated by TUNEL assay at day 3 post Dox or saline injections in a separate group. RESULTS: Three independent transgenic lines were generated, and all of them expressed cardiac specific Hsp27. Five days mortality was significantly reduced in TG group than that in WT group post Dox (P < 0.01), Dox induced cardiac dysfunction and cardiomyocyte apoptosis were also significantly attenuated in TG mice compared to WT mice (P < 0.05). CONCLUSION: Overexpression of Hsp27 reduced mortality, attenuated left ventricular dysfunction and cardiomyocyte apoptosis induced by Dox in a transgenic mouse model.

Over-expression of heat shock protein 27 attenuates doxorubicin-induced cardiac dysfunction in mice.

BACKGROUND: Oxidative stress and myocyte apoptosis are thought to play an important role in the pathogenesis, progression and prognosis of heart failure (HF). Heat shock protein 27 (Hsp27) has been found to confer resistance to oxidative stress in cultured cells; however, the role of Hsp27 in in-vivo hearts remains to be determined. AIM: To investigate the effects of Hsp27 over-expression on doxorubicin-induced HF. METHODS AND RESULTS: Transgenic mice (TG) with cardiac specific over-expression of Hsp27 and their wild type littermates (WT) were challenged with doxorubicin (25 mg/kg, IP) to induce HF. At day 5, TG mice had significantly improved cardiac function and viability and decreased loss of heart weight following doxorubicin exposure compared with WT. In another parallel experiment, doxorubicin-induced increased levels of reactive oxygen species, protein carbonylation, apoptosis and morphologic changes were detected in the mitochondria in WT hearts, whereas these effects were markedly attenuated in TG hearts. In addition, upregulation of heat shock protein 70 and heme oxygenase-1 was present in the TG hearts after doxorubicin stimulation in comparison to WT hearts. CONCLUSION: These findings indicate that Hsp27 may play a key role in resistance to doxorubicin-induced cardiac dysfunction.