Heat shock protein 27 attenuated doxorubicin-induced myocardial damage by reducing cardiomyocyte apoptosis, mitochondria damage and protein carbonylation / 中华心血管病杂志

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>(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.</p><p><b>CONCLUSION</b>Hsp27 could attenuate Dox-induced myocardial damage by reducing cardiomyocyte apoptosis, mitochondria damage and protein carbonylation.</p>

Overexpression of heat shock protein 27 reduces mortality and attenuates cardiac dysfunction induced by doxorubicin in a transgenic mouse model / 中华心血管病杂志

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSION</b>Overexpression of Hsp27 reduced mortality, attenuated left ventricular dysfunction and cardiomyocyte apoptosis induced by Dox in a transgenic mouse model.</p>

Heat shock protein 27 regulates oxidative stress-induced apoptosis in cardiomyocytes: mechanisms via reactive oxygen species generation and Akt activation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Increased reactive oxygen species (ROS) formation, which in turn promotes cardiomyocytes apoptosis, is associated with the pathogenesis and progression of various cardiac diseases such as ischemia and heart failure. Recent studies have shown that over expression of heat shock protein 27 (Hsp27) confers resistance to cardiac ischemia/reperfusion injury. However, not much is known about the regulation of myocyte survival by Hsp27.</p><p><b>METHODS</b>The rat cardiac cell line H9c2, with a stable overexpression of Hsp27, was established, with empty vector transfected H9c2 cells as controls. Following the cells challenged by Hydrogen Peroxide (H2O2), lactate dehydrogenase (LDH) release, apoptosis, intracellular ROS, cell morphology, mitochondrial transmembrane potential and the activation of serine/threonine kinase Akt were determined.</p><p><b>RESULTS</b>Along with marked suppression of H2O2-induced injury by Hsp27 overexpression in H9c2 cells, ROS generation and the loss of mitochondrial membrane potential were also significantly depressed. Furthermore, augmented Akt activation was observed in Hsp27 overexpressed H9c2 cells following H2O2 exposure.</p><p><b>CONCLUSIONS</b>Hsp27 inhibits oxidative stress-induced H9c2 damage and inhibition of ROS generation and the augmentation of Akt activation may be involved in the protective signaling.</p>

Adeno-associated virus-mediated CD40 ligand transfer into human lung cancer cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the transduction efficiency of serotype 1, 2, 5, 6, 7, 8, 9, 10 recombinant adeno-associated viruses (rAAV) in human lung cancer cell line A549 cells and compare the transduction efficiency of conventional AAV vectors with that of self-complementary AAV (scAAV) vectors. Furthermore, the capacity of A549 cells expressing transgenic CD40L to stimulate dendritic cells (DCs) was evaluated.</p><p><b>METHODS</b>Lung cancer A549 cells were infected with 1 x 10(4) particules per cell of AAV encoding the green fluorescent protein (GFP) or human CD40L driven by CMV promotor, and transgene expression was analyzed by flow cytometry and fluorescence microscopy. Stimulation of isolated human dendritic cells by CD40L-expressing tumor cells was quantified by measuring secreted interleukin-12 with immunoassay.</p><p><b>RESULTS</b>Serotype AAV2/5 transduced A549 cells much more efficiently than serotypes AAV2/1, AAV2/2, AAV2/6, AAV2/7, AAV2/8, AAV2/9 and AAV2/10. The transduction efficiency of scAAV2/5 was significantly higher than that of conventional AAV2/5. Furthermore, pre-treatment with carboplatin substantially increased AAV-mediated transgene expression. The scAAV2/5 vectors encoding human CD40L was used to generate CD40L. A549 cells transduce by these vectors were co-cultured with immature human DCs. As a consequence, interleukin-12 was released and measured in the culture supernatant. Specificity of immunostimulatory effect of CD40L was confirmed by blocking with a monoclonal antibody binding to human CD40L.</p><p><b>CONCLUSION</b>scAAV2/5 transduce lung adenocarcinoma A549 cell efficiently, and co-administration of chemotherapeutic agent carboplatin further enhances its transduction efficiency. It is confirmed that lung cancer cells infected with a CD40L-encoding scAAV2/5 construct can activate human DCs to secrete interleukin-12. Our findings provided a basis for future immunotherapeutic approaches including intratumoral transfer of stimulating factors.</p>

Association of thiazide-sensitive Na+-Cl* cotransporter gene polymorphisms with the risk of essential hypertension / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the association of thiazide-sensitive Na+ -Cl* cotransporter (TSC) gene 1784C/T and 2736G/A polymorphisms with the risk of essential hypertension (EH) in a Han nationality population.</p><p><b>METHODS</b>A community-based, case-control study including 190 EH patients and 94 sex- and age-matched controls was conducted. Genotypes of TSC gene 1784C/T and 2736G/A polymorphisms were analyzed by gene chip technology.</p><p><b>RESULTS</b>The genotype (1784C/T CC, CT, TT:87, 88, 15 vs 36, 52, 6û2736G/A GG, AG, AA:167, 22, 1 vs 83, 10, 1) and alleles frequency (1784C/T C, T:68.9%, 31.1% vs 66.0%, 34.0%; 2736G/A G,A:93.7%, 6.3% vs 93.6%, 6.4%) distribution of 1784C/T and 2736G/A showed no significant difference between the EH group and the control group (P >0.05). Moreover, no significant difference was observed in the frequencies distribution of four haplotypes (P > 0.05); Logistic regression analysis of haplotypes showed that the risk of EH had no significant difference in the population with different haplotypes (P > 0.05).</p><p><b>CONCLUSION</b>The 1784C/T and 2736G/A polymorphisms of TSC gene may not play an important role in the etiology of EH in a Han nationality population. The studies in the future are warranted to validate our findings.</p>

Effect of renin-angiotensin-aldosterone system gene polymorphisms on blood pressure response to antihypertensive treatment / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The renin-angiotensin-aldosterone system (RAAS) is important for the development of essential hypertension, and many antihypertensive drugs target it. This study was undertaken to determine whether polymorphisms in the renin-angiotensin-aldosterone system are related to the blood pressure (BP) response to diuretic treatment in a Chinese Han ethnic population.</p><p><b>METHODS</b>Fifty-four patients with essential hypertension received hydrochlorothiazide (12.5 mg, once daily) as monotherapy for four weeks. Seven polymorphisms in RAAS genes were genotyped by gene chip technology. The relationship between these polymorphisms and the change in blood pressure was observed after the 4-week treatment.</p><p><b>RESULTS</b>The patients with angiotensinogen (AGT) -6G allele showed a greater reduction in diastolic BP (P=0.025) and mean BP (P=0.039) than those carrying AA genotype. Patients carrying aldosterone synthase (CYP11B2) CC genotype exhibited a greater BP reduction than those carrying CT and TT genotypes (systolic BP: P=0.030; diastolic BP: P=0.026; mean BP: P=0.003). In addition, patients with a combination of CYP11B2 CC genotype and angiotensin converting enzyme (ACE) D allele might have a more pronounced reduction of systolic BP than those with any other genotypic combinations of the two genes (P=0.007).</p><p><b>CONCLUSIONS</b>AGT-6G allele, CYP11B2 -344CC genotype and its combination with ACE D allele are associated with BP response to hydrochlorothiazide treatment. Larger studies are warranted to validate this finding.</p>

Generation of Transgenic Mice with Cardiac-specific Overexpressing Heat Shock Protein 27 / 中国生物工程杂志

Objective:Increased reactive oxygen species (ROS) formation and by which in turn promotes cardiomyocytes apoptosis is associated with the pathogenesis and progression of various cardiac diseases. Small heat shock protein 27(Hsp27) could protect different cells from oxidative damage. By using tissue nonspecific overexpression Hsp 27 transgenic model, other investigators demonstrated that Hsp27 suppressed successfully kainate-induced seizures and hippocampal cell death in intact transgenic mice, and attenuated mimic ischemia/reperfusion injury in Langendorff-perfused isolated mice heart. As there are complicated and long distance neuro-humoral regulation associated with the development of cardiac diseases, it is better to choose a cardiac-specific overexpression transgenic model to study the effects of Hsp27 in hearts in vivo.Methods:A cDNA encoding human Hsp27 was subcloned into pBSII-SK+ containing the ?-myosin heavy chain (?-MHC) promoter (generously provided by Dr. J. Robbins, Children’s Hospital of Cincinnati, Ohio). BamHI-digested linear transgene consistent with the ?-MHC promoter, Hsp27 cDNA, and poly (A) of human growth hormone (hGH) was microinjected into the fertilized eggs from CBA/BL6 mice. Mice containing the transgene were identified by polymerase chain reaction. Founders revealed by this screening were used to establish independent transgenic lines. Following successful transmission, a range of tissues including heart, lung, liver, brain, skeleton muscle, spleen and kidney was screened by Western blot to confirm the cardiac specific expression of the transgene. Results and Discussion:Transgenic mice expressed Hsp27 under the control of a-MHC promoter. Cardiac tissues from independent TG line expressed abundant Hsp27, and as expected, Hsp27 expressed in cardiac tissues only, whereas none in liver, spleen, lung, kidney, brain and skeleton muscle. Surprisingly, Hsp25, the endogenous isoform of Hsp27 in murine, was downregulated by Hsp27 overexpression (data not shown), which is in contrast to the result of Hollander’s [1]. It needs to determine in future whether Hsp27 expression profile in heart could exert any effect on the regulation of Hsp25.Conclusion: The TG mice overexpression human Hsp27 specifically in the heart by using ?MHC- promotor were created. All TG mice expressed Hsp27 abundantly and cardiac-specifically. To our knowledge, it is the first report of creation of transgenic mice which overexpressing Hsp27 cardiac specifically. This current model suggests that the Hsp27 cardiac-specific over-expression of transgenic mouse remains a robust genetic tool for dissecting molecular and genetic events involving Hsp27, which could be a therapeutic target in heart failure.

Relationship between cyclooxygenase- 2 expression and angiogenesis in patients with gastric cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate COX-2 expression in patients with gastric cancer and its relationship with angiogenesis and clinicopathologic features of gastric cancer.</p><p><b>METHODS</b>COX-2 expression and CD34-stained microvessel density (MVD) were detected by immunohistochemical methods in specimens from 96 patients with gastric cancer. The correlations among COX-2 expression, MVD and clinicopathologic features were analyzed.</p><p><b>RESULTS</b>The COX-2 positive rate and MVD in gastric cancer were significantly higher than those in the normal gastric mucosa (80.2% vs. 13.3%; 32.5+/- 8.3 vs. 13.1+/- 2.4, all P< 0.01). The COX-2 positive rate and MVD in the patients with stage III and IV were significantly higher (91.4% and 34.9+/- 8.7 respectively, P< 0.01), than that in the patients with stage I and II. The COX-2 positive rate and MVD in the cases with lymph node metastasis were 87.9% and (35.0+/- 8.5) respectively, higher than those in the cases without lymph node metastasis (P< 0.05). The Spearman rank correlation test showed a significant correlation between COX-2 expression and tumor MVD (r=0.311, P< 0.01).</p><p><b>CONCLUSIONS</b>COX-2 plays an important role in gastric cancer angiogenesis. COX-2 and angiogenesis induced by COX-2 contribute to tumor invasion and lymph node metastasis.</p>

Effects of hsf1 genotype on the constitutive expression of alphaB-crystallin in mice myocardium / 中国应用生理学杂志

<p><b>AIM</b>Try to clarify the effects of HSF1 gene on the constitutively expressed alphaBC.</p><p><b>METHODS</b>To investigate the levels of constitutively expressed alphaB-Crystallin (alphaBC) in hsf1 knockout (hsf1 -/-) and hsf1 wild type (hsf1 +/+) mice myocardium by Western blot and immunohistochemistry.</p><p><b>RESULTS</b>The alphaBC levels in hsf1 -/- and hsf1 +/+ were 68.42% +/- 4.16%, 100% +/- 7.58%, respectively (P < 0.05, cytosolic fraction), and 20.53% +/- 1.01%, 37.55% +/- 1.91%, respectively (P < 0.05, pellet fraction). The alphaBC signals decreased significantly in hsf1 -/- myocardium compared with hsf1 +/+ myocardium stained with fluorescence immunohistochemistry.</p><p><b>CONCLUSION</b>hsf1 is the important, but not the only factor, which mediates the constitutively expressed alphaBC.</p>

Association of angiotensinogen gene polymorphisms with the risk of essential hypertension in the elderly / 中华检验医学杂志

Objective To investigate the association of angiotensinogen(AGT)gene A-6G、T174M and G-217A polymorphisms with the risk of essential hypertension(EH)in the elderly of Han nationality.Methods Genotypes of AGT gene A-6G,T174M and G-217A polymorphisms in 177 aged EH patients and 86 sex and age-matched controls were analyzed with gene chip technology.Results The A-6G and T174M polymorphisms of AGT gene were significantly associated with EH.The numbers of the three genotypes of A-6G were 113,58 and 6 in the patient group and 70,15 and 1 in the control group(P= 0.014)and those of T174M were 94,77 and 6,60,25 and 1(P=0.031),respectively.G-217A polymorphism was not related to EH.Individuals carrying A-6G AA and T174M CC genotypes showed 57% and 56% lower risk of EH(OR=0.43;95%CI=0.23-0.82 and OR=0.44;95%CI=0.25-0.79, respectively).Conclusions The A-6G AA and the T174M CC genotype may be related with decreased risk of EH and G-217A polymorphism may have little role in the etiology of EH in Han nationality.