Trimethylamine N-oxide facilitates the progression of atrial fibrillation in rats with type 2 diabetes by aggravating cardiac inflammation and connexin remodeling.

Diabetes is an independent risk factor for atrial fibrillation (AF). This study aimed to elucidate the pathophysiology of diabetes-related AF from the perspective of the gut microbial metabolite trimethylamine N-oxide (TMAO). In the present study, male rats received either a normal diet to serve as the control group or a high-fat diet/streptozotocin to induce type 2 diabetes mellitus. Then, diabetic rats were divided into two groups based on the presence or absence of 3,3-dimethyl-1-butanol (DMB, a specific TMAO inhibitor) in drinking water: the diabetic cardiomyopathy (DCM) group and the DCM + DMB group. Eight weeks later, compared with control rats, rats in the DCM group exhibited gut microbiota dysbiosis and systemic TMAO elevation. The inflammatory cytokines IL-1ß, IL-6, and TNF-α were markedly increased in the atria of rats in the DCM group. Downregulated expression of connexin 40 and lateralized distribution of connexin 43 were also observed in the atria of DCM rats. AF inducibility was significantly higher in DCM rats than in control rats. Furthermore, DMB treatment effectively ameliorated atrial inflammation and connexin remodeling while markedly reducing plasma TMAO levels. DMB treatment also decreased the vulnerability of diabetic rats to AF. In conclusion, TMAO might promote atrial inflammation and connexin remodeling in the development of diabetes, which may play a key role in mediating diabetes-related AF.

Hsa_circ_0016070/micro-340-5p Axis Accelerates Pulmonary Arterial Hypertension Progression by Upregulating TWIST1 Transcription Via TCF4/ß-Catenin Complex.

Background Hypoxia is considered a major leading cause of pulmonary hypertension (PH). In this study, the roles and molecular mechanism of circ_0016070 in PH were studied. Methods and Results The expression of circ_0016070 in serum samples, human pulmonary artery smooth muscle cells and hypoxia/monocrotaline-treated rats was determined by real-time quantitative polymerase chain reaction. Cell viability, migration, and apoptosis were analyzed by Cell Counting Kit-8, wound healing, flow cytometry, and TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) assays, respectively. The molecular interactions were validated using RNA immunoprecipitation, chromatin immunoprecipitation, and dual luciferase reporter assays. The levels of phenotype switch-related proteins were evaluated by Western blot and immunohistochemistry. The pathological characteristics were assessed using hematoxylin and eosin staining. circ_0016070 was highly expressed in the serum samples, hypoxia-induced pulmonary artery smooth muscle cells and pulmonary arterial tissues of PH rats. Downregulation of circ_0016070 ameliorated the excessive proliferation, migration, vascular remodeling, and phenotypic transformation but enhanced cell apoptosis in the PH rat model. In addition, micro (miR)-340-5p was verified as a direct target of circ_0016070 and negatively regulated TCF4 (transcription factor 4) expression. TCF4 formed a transcriptional complex with ß-catenin to activate TWIST1 (Twist family bHLH transcription factor 1) expression. Functional rescue experiments showed that neither miR-340-5p inhibition nor TWIST1 or TCF4 upregulation significantly impeded the biological roles of circ_0010670 silencing in PH. Conclusions These results uncovered a novel mechanism by which circ_0016070 play as a competing endogenouse RNA of miR-340-5p to aggravate PH progression by promoting TCF4/ß-catenin/TWIST1 complex, which may provide potential therapeutic targets for PH.

The MFF-SIRT1/3 axis, regulated by miR-340-5p, restores mitochondrial homeostasis of hypoxia-induced pulmonary artery smooth muscle cells.

Mitochondrial dynamics and quality control play a central role in the maintenance of the proliferation-apoptosis balance, which is closely related to the progression of pulmonary arterial hypertension (PAH). However, the exact mechanism of this balance remains unknown. Pulmonary artery smooth muscle cells (PASMCs) were cultured in hypoxia condition for constructing a PAH model in vitro. The expression of genes and proteins were determined by qRT-PCR and western bolt assays. Cell proliferation-apoptosis balance were tested by MTT, EdU and TUNEL assays. The mitochondrial functions were assessed by flow cytometry, JC-1, Mito tracker red staining, and corresponding kits. Besides, the molecular interaction was validated by dual-luciferase reporter assay. MFF was overexpressed in hypoxia-treated PAMSCs. Knockdown of MFF significantly repressed the excessive proliferation but enhanced cell apoptosis in hypoxia-treated PAMSCs. Moreover, MFF silencing improved mitochondrial function of hypoxia-treated PAMSCs by increasing ATP production and decreasing ROS release and mitochondrial fission. Mechanistically, MFF was a directly target of miR-340-5p, and could negatively regulate SIRT1/3 expression. Subsequently, functional rescue assays showed that the biological effects of MFF in hypoxia-treated PAMSCs were negatively regulated by miR-340-5p and depended on the regulation on SIRT1/3 pathway. These results provided evidences that miR-340-5p regulated MFF-SIRT1/3 axis to improve mitochondrial homeostasis and proliferation-apoptosis imbalance of hypoxia-treated PAMSCs, which provided a theoretical basis for the prevention and treatment of PAH.

Renal denervation ameliorates cardiac metabolic remodeling in diabetic cardiomyopathy rats by suppressing renal SGLT2 expression.

This study aimed to investigate the effects of renal denervation (RDN) on diabetic cardiomyopathy (DCM) and explore the related mechanisms. Male Sprague-Dawley rats were fed high-fat chow and injected with low-dose streptozotocin to establish a DCM model. Six rats served as controls. The surviving rats were divided into three groups: control group, DCM group and DCM + RDN group. RDN surgery was performed in the fifth week. At the end of the experiment, all rats were subjected to 18F-FDG PET/CT and metabolic cage studies. Cardiac function and structure were evaluated by echocardiography and histology. Myocardial substrate metabolism and mitochondrial function were assessed by multiple methods. In the 13th week, the DCM rats exhibited cardiac hypertrophy and interstitial fibrosis accompanied by diastolic dysfunction. RDN ameliorated DCM-induced cardiac dysfunction (E/A ratio: RDN 1.07 ± 0.18 vs. DCM 0.93 ± 0.12, P < 0.05; E/E' ratio: RDN 10.74 ± 2.48 vs. DCM 13.25 ± 1.99, P < 0.05) and pathological remodeling (collagen volume fraction: RDN 5.05 ± 2.05% vs. DCM 10.62 ± 2.68%, P < 0.05). Abnormal myocardial metabolism in DCM rats was characterized by suppressed glucose metabolism and elevated lipid metabolism. RDN increased myocardial glucose uptake and oxidation while reducing the absorption and utilization of fatty acids. Meanwhile, DCM decreased mitochondrial ATP content, depolarized the membrane potential and inhibited the activity of respiratory chain complexes, but RDN attenuated this mitochondrial damage (ATP: RDN 30.98 ± 7.33 µmol/gprot vs. DCM 22.89 ± 5.90 µmol/gprot, P < 0.05; complexes I, III and IV activity: RDN vs. DCM, P < 0.05). Furthermore, both SGLT2 inhibitor and the combination treatment produced similar effects as RDN alone. Thus, RDN prevented DCM-induced cardiac dysfunction and pathological remodeling, which is related to the improvement of metabolic disorders and mitochondrial dysfunction.

Neuronal nitric oxide synthase in dorsal raphe nucleus mediates PTSD-like behaviors induced by single-prolonged stress through inhibiting serotonergic neurons activity.

The pathogenesis of post-traumatic stress disorder (PTSD) remains largely unclear. A large body of evidence suggests that the abnormal level of serotonin (5-HT) is closely related to the onset of PTSD. Several reports reveal that nitric oxide (NO) affects extracellular 5-HT levels in various brain regions, but no consistent direction of change was found and the underlying mechanisms remain unknown. The most of serotonergic neurons in dorsal raphe nucleus (DRN), a major source of serotonergic input to the forebrain, co-expresses neuronal nitric oxide synthase (nNOS), a synthase derived nitric oxide (NO) in the central nervous system. Here, we found that the excessive expression of nNOS and thereby the high concentration of NO followed by single-prolonged stress (SPS) caused suppression of the activity of DRN 5-HT neurons, inducing PTSD-like phenotype including increased anxiety-like behaviors, enhanced contextual fear memory, and fear generalization. Our study uncovered an important role of DRN nNOS-NO pathway in the pathology of PTSD, which may contribute to new understanding of the molecular mechanism of PTSD.

Intestinal Barrier Dysfunction Exacerbates Neuroinflammation via the TLR4 Pathway in Mice With Heart Failure.

AIMS: The present study aimed to investigate alterations in neuroinflammation after heart failure (HF) and explore the potential mechanisms. METHODS: Male wild-type (WT) and Toll-like receptor 4 (TLR4)-knockout (KO) mice were subjected to sham operation or ligation of the left anterior descending coronary artery to induce HF. 8 weeks later, cardiac functions were analyzed by echocardiography, and intestinal barrier functions were examined by measuring tight junction protein expression, intestinal permeability and plasma metabolite levels. Alterations in neuroinflammation in the brain were examined by measuring microglial activation, inflammatory cytokine levels and the proinflammatory signaling pathway. The intestinal barrier protector intestinal alkaline phosphatase (IAP) and intestinal homeostasis inhibitor L-phenylalanine (L-Phe) were used to examine the relationship between intestinal barrier dysfunction and neuroinflammation in mice with HF. RESULTS: Eight weeks later, WT mice with HF displayed obvious increases in intestinal permeability and plasma lipopolysaccharide (LPS) levels, which were accompanied by elevated expression of TLR4 in the brain and enhanced neuroinflammation. Treatment with the intestinal barrier protector IAP significantly attenuated neuroinflammation after HF while effectively increasing plasma LPS levels. TLR4-KO mice showed significant improvements in HF-induced neuroinflammation, which was not markedly affected by intestinal barrier inhibitors or protectors. CONCLUSION: HF could induce intestinal barrier dysfunction and increase gut-to-blood translocation of LPS, which could further promote neuroinflammation through the TLR4 pathway.

Renal Denervation Attenuates Neuroinflammation in the Brain by Regulating Gut-Brain Axis in Rats With Myocardial Infarction.

Aims: The development of neuroinflammation deteriorates the prognosis of myocardial infarction (MI). We aimed to investigate the effect of renal denervation (RDN) on post-MI neuroinflammation in rats and the related mechanisms. Methods and Results: Male adult Sprague-Dawley rats were subjected to sham or ligation of the left anterior descending coronary artery to induce MI. One week later, the MI rats received a sham or RDN procedure. Their cardiac functions were analyzed by echocardiography, and their intestinal structures, permeability, and inflammatory cytokines were tested. The intestinal microbiota were characterized by 16S rDNA sequencing. The degrees of neuroinflammation in the brains of rats were analyzed for microglia activation, inflammatory cytokines, and inflammation-related signal pathways. In comparison with the Control rats, the MI rats exhibited impaired cardiac functions, intestinal injury, increased intestinal barrier permeability, and microbial dysbiosis, accompanied by increased microglia activation and pro-inflammatory cytokine levels in the brain. A RDN procedure dramatically decreased the levels of renal and intestinal sympathetic nerve activity, improved cardiac functions, and mitigated the MI-related intestinal injury and neuroinflammation in the brain of MI rats. Interestingly, the RDN procedure mitigated the MI-increased intestinal barrier permeability and pro-inflammatory cytokines and plasma LPS as well as ameliorated the gut microbial dysbiosis in MI rats. The protective effect of RDN was not significantly affected by treatment with intestinal alkaline phosphatase but significantly reduced by L-phenylalanine treatment in MI rats. Conclusions: RDN attenuated the neuroinflammation in the brain of MI rats, associated with mitigating the MI-related intestinal injury.

Depletion of Survivin suppresses docetaxel-induced apoptosis in HeLa cells by facilitating mitotic slippage.

The anticancer effects of taxanes are attributed to the induction of mitotic arrest through activation of the spindle assembly checkpoint. Cell death following extended mitotic arrest is mediated by the intrinsic apoptosis pathway. Accordingly, factors that influence the robustness of mitotic arrest or disrupt the apoptotic machinery confer drug resistance. Survivin is an inhibitor of apoptosis protein. Its overexpression is associated with chemoresistance, and its targeting leads to drug sensitization. However, Survivin also acts specifically in the spindle assembly checkpoint response to taxanes. Hence, the failure of Survivin-depleted cells to arrest in mitosis may lead to taxane resistance. Here we show that Survivin depletion protects HeLa cells against docetaxel-induced apoptosis by facilitating mitotic slippage. However, Survivin depletion does not promote clonogenic survival of tumor cells but increases the level of cellular senescence induced by docetaxel. Moreover, lentiviral overexpression of Survivin does not provide protection against docetaxel or cisplatin treatment, in contrast to the anti-apoptotic Bcl-xL or Bcl-2. Our findings suggest that targeting Survivin may influence the cell response to docetaxel by driving the cells through aberrant mitotic progression, rather than directly sensitizing cells to apoptosis.

Effects of Angiotensin Receptor Neprilysin Inhibitors on Inducibility of Ventricular Arrhythmias in Rats with Ischemic Cardiomyopathy.

The aims of the present study were to investigate the effects of angiotensin receptor neprilysin inhibitors (ARNi) on the susceptibility of ventricular arrhythmias (VAs) in rats with myocardial infarction (MI) and to explore the related mechanisms.A total of 32 adult male Sprague-Dawley rats were divided into 3 groups: a control group, MI group, and MI+ARNi group. MI was generated by ligation of the left anterior descending coronary artery. ARNi was given at 68 mg/kg/day for 4 weeks after MI surgery. At 4 weeks after MI, electrical programmed stimulation (EPS) was performed in all groups for the evaluation of VAs, and echocardiography was used to evaluate cardiac function. Indicators of sympathetic neural remodeling and cardiac remodeling were detected to further explore the related mechanisms.Four weeks after MI, rats in the ARNi group exhibited low susceptibility of VAs in comparison with that in the MI group, which was coincident with the attenuation of sympathetic nerve remodeling, amelioration of cardiac fibrosis, and regulation of Cx43 expression.ARNi is effective in reducing VAs in rats with ischemic cardiomyopathy, which is associated with attenuating sympathetic nerve remodeling and myocardial fibrosis.

Renal denervation ameliorates post-infarction cardiac remodeling in rats through dual regulation of oxidative stress in the heart and brain.

BACKGROUND: Myocardial remodeling is the key step in the development of ischemic cardiomyopathy. We aimed to compare effects of renal denervation (RDN) with those of angiotensin receptor neprilysin inhibitors (ARNi) on cardiac remodeling after myocardial infarction (MI), and explore underlying mechanism. METHODS: Sprague-Dawley rats (n = 40; male) were subjected to ligation of left anterior descending coronary artery to induce MI; six rats served as controls. ARNi was administered at a dose of 60 mg/kg/day for 4 weeks starting 1 week after MI. An RDN/Sham-RDN procedure was performed 1 week after MI. Rats in all groups were studied 5 weeks after MI. Echocardiography was used to evaluate cardiac function. Masson staining and TUNEL staining were used to determine the extent of cardiac remodeling. Indicators of oxidative stress in heart and brain were used to analyze the potential mechanisms involved. RESULTS: Five weeks after MI, both RDN and ARNi significantly improved cardiac function and cardiac remodeling; however, RDN was superior to ARNi at attenuating myocardial apoptosis. Compared to ARNi, RDN was also more effective at decreasing the abnormal oxidative stress caused by MI; this was especially true in case of the brain and was confirmed by evaluating the changes in reactive oxygen species (ROS) levels and other oxidative stress parameters following MI. CONCLUSIONS: RDN is not inferior to ARNi with respect to the improvement of cardiac remodeling in rats with ischemic cardiomyopathy. The effect of RDN might be associated with effective inhibition of oxidative stress in both the heart and brain.

Renal denervation attenuates pressure overload-induced cardiac remodelling in rats with biphasic regulation of autophagy.

AIM: This study aimed to investigate effects of renal denervation (RDN) on pressure overload-induced cardiac remodelling in rats and the related mechanisms. METHODS: Adult male Sprague-Dawley rats underwent transverse aortic constriction (TAC) to generate cardiac remodelling. RDN was performed 1 week after TAC. The animals were divided into four groups: control group, TAC group, TAC+RDN group and control+RDN group. Rats in all groups were studied at 3 and 10 weeks after TAC respectively. Echocardiography and histology were used to evaluate cardiac function and pathological changes. TUNEL staining and western blotting were used to assess apoptosis. Western blotting and transmission electron microscopy (TEM) were used to evaluate autophagy. RESULTS: Three weeks after TAC, the TAC rats exhibited cardiac hypertrophy with normal cardiac function and no myocardial interstitial fibrosis or apoptosis, accompanied by a lower LC3 II level and fewer autophagic vacuoles in the left ventricles, both in the presence and absence of chloroquine (CQ), indicating suppressed autophagy at this stage. RDN ameliorated these pathological changes and attenuated the decrease in autophagy. Ten weeks after TAC, the TAC rats had decreased cardiac function, obvious cardiac interstitial fibrosis and apoptosis, with increased autophagy. RDN prevented these pathological changes, coincident with attenuation of increased autophagy. CONCLUSION: Autophagy was suppressed at the early stage but activated at the late stage of TAC-induced cardiac remodelling. RDN attenuated the pathological changes of TAC rats, accompanied by attenuation of the changes in autophagy. Thus, RDN ameliorated TAC-induced cardiac remodelling partially associated with biphasic modulation of autophagy.

[Prevalence of human papilloma virus infection and its risk factors in some rural areas of Jiangsu, China].

OBJECTIVE: To investigate human papilloma virus (HPV) infection in the male genital tract and its risk factors in some rural areas of Jiangsu Province. METHODS: This study included 398 men from six rural areas in Jiangsu Province, whose female partners, based on the results of cervical cytological examination, were divided into a normal (n = 104), a cervical intraepithelial neoplasia grade Ⅰ (CIN-Ⅰ, n = 100), a CIN-Ⅱ (n = 95), and a CIN-Ⅲ group (n = 99). We examined the male subjects for genital warts and other lesions, collected urethral swab samples for HPV detection, and obtained their sociodemographic data by questionnaire investigation. RESULTS: No megascopic lesions were observed in the genitals of the 398 participants. The total prevalence rate of HPV infection was 11.31% and that of high-risk HPV was 8.54%. Logistic regression analysis showed that daily cleaning of the genitals significantly decreased the risk of HPV infection (OR = 3.030, P = 0.003). CONCLUSIONS: There is a relatively high prevalence rate of recessive infection of genital HPV among the seemingly healthy males in the rural area of Jiangsu Province. Daily cleaning of the genitals may be a protective measure against HPV infection.

Using Electrical Stimulation to Enhance the Efficacy of Cell Transplantation Therapies for Neurodegenerative Retinal Diseases: Concepts, Challenges, and Future Perspectives.

Disease or trauma-induced loss or dysfunction of neurons in any central nervous system (CNS) tissue will have a significant impact on the health of the affected patient. The retina is a multilayered tissue that originates from the neuroectoderm, much like the brain and spinal cord. While sight is not required for life, neurodegeneration-related loss of vision not only affects the quality of life for the patient but also has societal implications in terms of health care expenditure. Thus, it is essential to develop effective strategies to repair the retina and prevent disease symptoms. To address this need, multiple techniques have been investigated for their efficacy in treating retinal degeneration. Recent advances in cell transplantation (CT) techniques in preclinical, animal, and in vitro culture studies, including further evaluation of endogenous retinal stem cells and the differentiation of exogenous adult stem cells into various retinal cell types, suggest that this may be the most appropriate option to replace lost retinal neurons. Unfortunately, the various limitations of CT, such as immune rejection or aberrant cell behavior, have largely prevented this technique from becoming a widely used clinical treatment option. In parallel with the advances in CT methodology, the use of electrical stimulation (ES) to treat retinal degeneration has also been recently evaluated with promising results. In this review, we propose that ES could be used to enhance CT therapy, whereby electrical impulses can be applied to the retina to control both native and transplanted stem cell behavior/survival in order to circumvent the limitations associated with retinal CT. To highlight the benefits of this dual treatment, we have briefly outlined the recent developments and limitations of CT with regard to its use in the ocular environment, followed by a brief description of retinal ES, as well as described their combined use in other CNS tissues.

A Meta-analysis of Central Corneal Thickness Changes With Overnight Orthokeratology.

OBJECTIVES: To assess the change of central corneal thickness (CCT) in the treatment of orthokeratology in patients with myopia. METHODS: A systematic search of all relevant studies published through April 2014 was conducted, and 95% confidence intervals (CI) of CCT change were calculated. Random or fixed-effects models were used according to heterogeneity. Publication bias of the articles was evaluated using funnel plots and Begg test. RESULTS: A total of 10 studies with 239 patients (339 eyes) from clinical studies were included. Central corneal thickness reduced significantly from 1 day to 1 week by 5.73 µm (95% CI, 1.75-9.70 µm; P=0.005), and a significant mean reduction of 5.89 µm also occurred from 1 day to 1 month (95% CI, 3.50-8.29 µm; P<0.001). No significant reduction was found between 1 week and 1 month (P=0.32). CONCLUSIONS: Our meta-analysis demonstrated that most reduction of CCT occurred during the first week and remained thinner for 1 month. Further randomized controlled trials with larger sample sizes, standardized outcome measurements, and different follow-up periods are warranted to find the precise change.

Mesenchymal Stem Cells Stabilize Atherosclerotic Vulnerable Plaque by Anti-Inflammatory Properties.

BACKGROUND AND OBJECTIVES: Formation and progression of atherosclerotic vulnerable plaque (VP) is the primary cause of many cardio-cerebrovascular diseases such as acute coronary syndrome and stroke. It has been reported that bone marrow mesenchymal stem cells (MSC) exhibit protective effects against many kinds of diseases including myocardial infarction. Here, we examined the effects of intravenous MSC infusion on a VP model and provide novel evidence of its influence as a therapy in this animal disease model. SUBJECTS AND METHODS: Thirty healthy male New Zealand white rabbits were randomly divided into a MSC, VP or stable plaque (SP) group (n = 10/group) and received high fat diet and cold-induced common carotid artery intimal injury with liquid nitrogen to form atherosclerotic plaques. Serum hs-CRP, TNF-α, IL-6 and IL-10 levels were measured by ELISA at 1, 2, 3, 7, 14, 21 and 28 days after MSC transplantation. The animals were sacrificed at 4 weeks after MSC transplantation. Lesions in the right common carotid were observed using H&E and Masson staining, and the fibrous cap/lipid core ratio of atherosclerotic plaques were calculated. The expression of nuclear factor κB (NF-κB) and matrix metalloproteinase 1, 2, 9 (MMP-1,2,9) in the plaque were detected using immunohistochemistry, and apoptotic cells in the plaques were detected by TUNEL. In addition, the level of TNF-α stimulated gene/protein 6 (TSG-6) mRNA and protein were measured by quantitative Real-Time PCR and Western blotting, respectively. RESULTS: Two rabbits in the VP group died of lung infection and cerebral infarction respectively at 1 week after plaque injury by liquid nitrogen. Both H&E and Masson staining revealed that the plaques from the SP and MSC groups had more stable morphological structure and a larger fibrous cap/lipid core ratio than the VP group. Serum hs-CRP, TNF-α and IL-6 were significantly down-regulated, whereas IL-10 was significantly up-regulated in the MSC group compared with the VP group. .Immunohistochemistry analysis revealed that NF-κB and MMP expression was reduced in the MSC and SP groups compared to the VP group. Cell apoptosis decreased significantly in both the MSC and SP groups in comparison to the VP group. TSG-6 mRNA and protein expression were higher in the plaques of the MSC group compared to the VP and SP groups. CONCLUSIONS: Our study results suggest that MSC transplantation can effectively stabilize vulnerable plaques in atherosclerotic rabbits. This may potentially offer a new clinical application of MSC in atherosclerosis.

Spliced XBP1 promotes macrophage survival and autophagy by interacting with Beclin-1.

Macrophage autophagy plays an important role in the development of atherosclerosis, but the precise mechanism mediating this process is unclear. The potential role of the X-box binding protein 1 (XBP1), a crucial transduction factor that is involved in endoplasmic reticulum stress and the unfolded protein response, in bone marrow-derived macrophage autophagy is unknown. This study mainly explores the roles of XBP1 mRNA splicing in bone marrow-derived macrophage autophagy. The present study shows that the transient overexpression of spliced XBP1 via adenovirus-mediated gene transfer induces autophagy and promotes proliferation in bone marrow-derived macrophages via the down-regulation of Beclin-1, but that the sustained overexpression of spliced XBP1 leads to apoptosis. When XBP1 is down-regulated in bone marrow-derived macrophages using siRNA, rapamycin-induced autophagosome formation is ablated. Furthermore, we have detected the overexpression of XBP1 in areas of atherosclerotic plaques in the arteries of ApoE-/- mice. These results demonstrate that XBP1 mRNA splicing plays an important role in maintaining the function of bone marrow-derived macrophages and provide new insight into the study and treatment of atherosclerosis.

[Protective effect of thymosin ß4 against oxidative damage in cultured rabbit corneal epithelial cells].

OBJECTIVE: The aim of this study was to investigate the effects of thymosin ß4 (Tß4) against oxidative damage in rabbit corneal epithelial cells in vitro. METHODS: Experimental study. Primary cultures of rabbit corneal epithelial cells were isolated and cultured from cornea tissue explants. Cell morphology was observed by phase-contrast microscope. The expression of keratin 12 and connexin 43 in cultured cells were examined with RT-PCR. The cultures were divided into 4 groups: control group, Tß4 group, hydrogen peroxide (H2O2) group, and H2O2+Tß4 group. The cell viability of cultured corneal epithelial cells was examined by MTT assay. TUNEL staining was used to detect the apoptotic cells. ROS levels were estimated by DCFH-DA using fluorescent microscopy. Cell migration was measured using the scratch wound technique. Data were analyzed using one-way analysis of variance (ANOVA) and secondary analysis for significance with post Hoc tests. RESULTS: The morphology of cultured cells was round, ovoid, polygonal or paving stone appearance. The results of RT-PCR showed that cultured corneal epithelial cells expressed both keratin 12 and connexin 43, the characteristic genes of corneal epithelial cells. The cell viability in H2O2 group was significantly reduced than that in control group (67.20% ± 5.87% vs. 100.00% ± 9.99%, P = 0.000); the cell viability was significantly improved in Tß4+ H2O2 group than that in H2O2 group (83.42% ± 7.23% vs. 67.20% ± 5.87%, P = 0.023) . Cell migration was significantly increased in Tß4 group compared with the controls (117.6% ± 2.22% vs. 100.00% ± 4.06%, P = 0.005) ; Compared with H2O2 group, cell migration was significant increase in H2O2 + Tß4 group (96.57% ± 8.22% vs. 64.38% ± 11.08%, P = 0.000) . Compared with the control group, the intracellular ROS level of the H2O2 group was significantly increased (234.42% ± 22.15% vs. 100.00% ± 5.28%, P = 0.000) . Intracellular ROS level of H2O2+Tß4 group was significantly decreased as compared with the H2O2 group (163.26% ± 10.53% vs. 234.42% ± 22.15%, P = 0.000). TUNEL staining indicated that Tß4 treatment markedly inhibited H2O2-induced apoptosis in cultured corneal epithelial cells. CONCLUSIONS: Tß4 has a strong protection effect against oxidative damage induced by H2O2 in corneal epithelial cells through promoting cell growth and cell migration, and the underlying mechanisms may due to the antioxidation and anti-apoptotic effects of Tß4.

Prognostic value of ultra-sensitive pregnancy associated plasma protein-A in patients with acute coronary syndrome.

OBJECTIVE: To investigate the prognostic value of ultra-sensitive pregnancy associated plasma protein-A (PAPP-A) level in the early phase of acute coronary syndrome (ACS) attack. METHODS: Patients diagnosed as ACS were enrolled and the level of circulatory PAPP-A was measured within 12 hours after ACS attack. The patients were followed at the time of 1st, 6th, and 12th months post-ACS attack in order to observe the incidence of the cardiovascular adverse events. According to the highest quintile, the patients were divided into 2 groups: high level (≥26.08 µg/L) group and low level (<26.08 µg/L) group, to evaluate the association between the level of PAPP-A and the incidence of the cardiovascular events. RESULTS: Compared with the low level group, the incidence of the composite outcome is significantly increased in the high level group, and the values of OR are 4.76, 4.38, 3.75 for 1st, 6th, 12th months respectively (P=0.000). For myocardial infarction (MI) + cardiac death (CD) the values of OR were 9.81, 6.08, 4.12 (P<0.01). Multivariate logistic regression analysis demonstrates that PAPP-A was an independent risk factor for the cardiovascular adverse events in the early, median, and late phase of ACS (P<0.05). CONCLUSION: In the early phase of ACS attack, the elevation of PAPP-A is an independent risk factor for the occurrence of cardiovascular adverse events.

Developing a novel rabbit model of atherosclerotic plaque rupture and thrombosis by cold-induced endothelial injury.

BACKGROUND: It is widely believed that atherosclerotic plaque rupture and subsequent thrombosis leads to acute coronary events and stroke. However, study of the mechanism and treatment of human plaque rupture is hampered by lack of a suitable animal model. Our aim was to develop a novel animal model of atherosclerotic plaque rupture to facilitate the study of human plaque disruption and thrombosis. METHODS: 28 healthy male New Zealand white rabbits were randomly divided into two groups: rabbits in group A (n = 12) were only fed a high-fat diet for eight weeks; rabbits in group B (n = 16) underwent cold-induced endothelial injury with liquid nitrogen, then were given a high-fat diet for eight weeks. After completion of the preparatory regimen, triggering of plaque rupture was attempted by local injection of liquid nitrogen in both groups. RESULTS: All rabbits in group B had disrupted plaques or rupture-driven occlusive thrombus formation, but none in group A showed any effects. More importantly, the cold-induced plaques in our model were reminiscent of human atherosclerotic plaques in terms of architecture, cellular composition, growth characteristics, and patterns of lipid accumulation. CONCLUSION: We successfully developed a novel rabbit model of atherosclerotic plaque rupture and thrombosis, which is simple, fast, inexpensive, and reproducible, and has a low mortality and a high yield of triggering. This model will allow us to better understand the mechanism of human plaque rupture and also to develop plaque-stabilizing therapies.