Pathogen distribution in pulmonary infection in chinese patients with lung cancer: a systematic review and meta-analysis.

BACKGROUND: The immunity of patients with lung cancer decreases after treatment; thus, they are easily infected with pathogenic bacteria that causes pulmonary infections. Understanding the distribution characteristics of pathogenic bacteria in pulmonary infection in patients with lung cancer after treatment can provide a basis to effectively prevent infection and rationally use antibacterial drugs. However, no meta-analyses have assessed the distribution characteristics of pathogenic bacteria in mainland China. Therefore, our meta-analysis aimed to investigate the pathogen distribution in pulmonary infection in Chinese patients with lung cancer. METHODS: A literature search was conducted to study the pathogen distribution in pulmonary infection in Chinese patients with lung cancer between January 1, 2020 and December 31, 2022, using English and Chinese databases. The relevant data were extracted. The meta-analysis was performed using a random-effects model ( I2 > 50%) with 95% confidence intervals for forest plots. Data were processed using RevMan 5.3. RESULTS: Fifteen studies (2,683 strains in 2,129 patients with pulmonary infection were cultured) met the evaluation criteria. The results showed that Gram-negative bacteria had the highest detection rate (63%), followed by Gram-positive bacteria (23%), and fungi (12%). Among the Gram-negative bacteria detected, the distribution of the main pathogenic bacteria was Klebsiella pneumonia (17%), Pseudomonas aeruginosa (14%), Escherichia coli (13%), Acinetobacter baumannii (7%), Enterobacter cloacae (4%), and Hemophilus influenza (4%). Moreover, the prevalence of pulmonary infections after chemotherapy (53%) was significantly higher than that after surgery (10%), P < 0.05. CONCLUSIONS: The prevalence of pulmonary infections after treatment, especially after chemotherapy, is high in Chinese patients with lung cancer, and Gram-negative bacteria are the predominant pathogens. Further studies are needed to monitor the prevalence of pulmonary infections and pathogen distribution in lung cancer patients in mainland China.

Combination of tolvaptan and valsartan improves cardiac and renal functions in doxorubicin-induced heart failure in mice.

Heart failure (HF) is often complicated by renal dysfunction. Tolvaptan and valsartan are two well-known agents for the treatment of HF. However, the role of tolvaptan/valsartan combination on HF with renal dysfunction remains unclear. To establish a mice model with HF with renal dysfunction, mice were intraperitoneally injected with doxorubicin (Dox). Echocardiogram was applied to assess the left ventricular function. Additionally, serum aldosterone (ALD) and angiotensin II (Ang II) level in mice were determined by ELISA. Meanwhile, western blot assay was used to evaluate the expressions of B cell lymphoma-2 (Bcl-2), Bcl-2 associated X (Bax) and cleaved caspase 3 in the heart and kidney tissues of mice. In this study, we found that compared to tolvaptan or valsartan alone treatment group, tolvaptan/valsartan combination obviously improved the left ventricular ejection fraction (LVEF) and the left ventricular fractional shortening (LVFS), and reduced serum ALD and Ang II level in Dox-treated mice. Additionally, tolvaptan/valsartan combination significantly prevented the inflammation and fibrosis of heart and kidney tissues in Dox-treated mice. Meanwhile, tolvaptan/valsartan combination notably inhibited the myocardial and renal cell apoptosis in Dox-treated mice via upregulation of Bcl-2 and downregulation of Bax and cleaved caspase 3, compared to the single drug treatment. Collectively, tolvaptan/valsartan combination could improve cardiac and renal functions, as well as prevent the fibrosis, inflammation and apoptosis of heart and kidney tissues in Dox-treated mice. Taken together, combining tolvaptan with valsartan might be a promising approach to achieve enhanced therapeutic effect for treatment of HF with renal dysfunction.

Adherence to Healthy Lifestyle and the Risk of Function Limitations in Late Life: The Atherosclerosis Risk in Communities Study.

Background: Physiological function impairment is the main precursor of assisted living, movement disorder, and disability in the elderly. The relationship between a combination of healthy lifestyle factors and functional limitations is unclear. We investigated the association between healthy lifestyle scores and the risk of functional impairment in community residents. Methods: A total of 10,602 participants (aged 40-64 years) of the Atherosclerosis Risk in Communities (ARIC) study with no history of cardiovascular events and tumors and who came for their fourth visit (1997-1999) were included in the final analysis. Primary outcomes were recorded during the fourth visit; these included impaired lower extremity function, activities of daily living, and instrumental activities of daily living. A logistic regression model was used to test the associations between healthy lifestyle scores and functional impairment. The lifestyle score comprised six factors: healthy diet, moderate alcohol consumption, coffee consumption, physical activity, normal body weight, and no smoking. Results: Among the 10,602 participants with a median follow-up of 9 years, the prevalence rates of impaired lower extremity function, activities of daily living, and instrumental activities of daily living were 50.6%, 14.7%, and 21.6%, respectively. In the adjusted Cox regression model, participants with a healthy lifestyle score of 5 plus 6 had a significant lower risk of impaired lower extremity function (odds ratio = 0.252, 95% confidence interval: 0.184-0.344, P < 0.001), activities of daily living (odds ratio = 0.201, 95% confidence interval: 0.106-0.380, P < 0.001), and instrumental activities of daily living (odds ratio = 0.274, 95% confidence interval: 0.168-0.449, P < 0.001) than did participants with a score of 0. The association of healthy lifestyle scores with impaired activities of daily living and instrumental activities of daily living was stronger for individuals without diabetes than for those with it (P for interaction < 0.05). This can be partly explained by the fact that the lowest risk of functional impairment among the participants with diabetes was associated with being overweight. Conclusion: Adherence to an overall healthy lifestyle was associated with a lower risk of physiological function limitation. This study highlights the importance of behavioral interventions in the prevention of disabilities. Clinical Trial Registration: www.ClinicalTrials.gov; Unique identifier: NCT00005131.

Adherence to a Healthy Lifestyle and the Risk of All-Cause Mortality and Cardiovascular Events in Individuals With Diabetes: The ARIC Study.

Objective: The relationship between combined healthy lifestyle and cardiovascular (CV) events in diabetes is unclear. We aim to investigate the association between a healthy lifestyle score (HLS) and the risk of mortality and CV events in diabetes. Methods: We examined the associations of six lifestyle factors scores (including healthy diet, moderate alcohol and regular coffee intakes, never smoking, physical activity, and normal weight) with diabetes in the Atherosclerosis Risk in Communities (ARIC) study of 3,804 participants with diabetes from the United States at baseline. Primary outcomes included all-cause mortality, CV mortality, and composite CV events (heart failure hospitalizations, myocardial infarction, fatal coronary heart disease, and stroke). Results: Among these diabetic participants, 1,881 (49.4%), 683 (18.0%), and 1,600 (42.0%) cases of all-cause mortality, CV mortality, and CV events were documented, respectively, during the 26 years of follow-up. Further, the prevalence of these adverse events became lower with the increase of HLS (all P < 0.001). In the risk-factors adjusted Cox regression model, compared to participants with HLS of 0, participants with HLS of 2 had significant lower risk of all-cause mortality (HR = 0.811, 95% CI: 0.687-0.957, P = 0.013), CV mortality (HR = 0.744, 95% CI: 0.576-0.962, P = 0.024), and CV events (HR = 0.789, 95% CI: 0.661-0.943, P = 0.009). The association of HLS with CV events was stronger for women than men (P for interaction <0.05). Conclusion: Adherence to a healthy lifestyle was associated with a lower risk of CV events and mortality in diabetics. Our findings suggest that the promotion of a healthy lifestyle would help reduce the increasing healthcare burden of diabetes. Clinical Trial Registration: https://clinicaltrials.gov, Identifier: NCT00005131.

MicroRNA-126 enhances the biological function of endothelial progenitor cells under oxidative stress via PI3K/Akt/GSK3ß and ERK1/2 signaling pathways.

Endothelial progenitor cell (EPC) transplantation is a safe and effective method to treat acute myocardial infarction (AMI). However, oxidative stress leads to the death of a large number of EPCs in the early stage of transplantation, severely weakening the therapeutic effect. Previous studies demonstrated that microRNAs regulate the biological function of EPCs. The aim of the current study was to investigate the effect of microRNA on the biological function of EPCs under oxidative stress. Quantitative reverse transcription PCR was performed to detect the expression of miR-126, miR-508-5p, miR-150, and miR-16 in EPCs from rats, among which miR-126 showed a relatively higher expression. Treatment with H2O2 decreased miR-126 expression in EPCs in a dose-dependent manner. EPCs were further transfected with miR-126 mimics or inhibitors, followed by H2O2 treatment. Overexpression of miR-126 enhanced the proliferation, migration, and tube formation of H2O2-treated EPCs. MiR-126 overexpression also inhibited reactive oxygen species and malondialdehyde levels and enhanced superoxide dismutase levels, as well as increased angiopoietin (Ang)1 expression and decreased Ang2 expression in H2O2-treated EPCs. Moreover, miR-126 participated in the regulation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/glycogen synthase kinase 3ß (GSK3ß) and extracellular signal-regulated kinase 1/2 (ERK1/2) signaling in EPCs, where both pathways were activated after miR-126 overexpression in H2O2-treated EPCs. Overall, we showed that miR-126 promoted the biological function of EPCs under H2O2-induced oxidative stress by activating the PI3K/Akt/GSK3ß and ERK1/2 signaling pathway, which may serve as a new therapeutic approach to treat AMI.

Anti­Nogo­A antibody promotes brain function recovery after cardiopulmonary resuscitation in rats by reducing apoptosis.

Brain injury after cardiac arrest (CA) and cardiopulmonary resuscitation (CPR) is the main cause of neurological dysfunction and death in cardiac arrest. To assess the effect of Nogo­A antibody on brain function in rats following CPR and to explore the underlying mechanisms, CA/CPR (ventricular fibrillation) rats were divided into the CPR+Nogo­A, CPR+saline and sham groups. Hippocampal caspase­3 levels were detected by RT­PCR and immunoblotting. Next, Nogo­A, glucose regulated protein 78 (GRP78), C/EBP homologous protein (CHOP), cysteinyl aspartate specific proteinase­12 (casapse­12), Bcl­2 and Bax protein levels in the hippocampus were detected by immunoblotting. Coronal brain sections were analyzed by TUNEL assay to detect apoptosis at 72 h, while Nissl staining and electron microscopy were performed to detect Nissl bodies and microstructure at 24 h, respectively. Finally, rats were assessed for neurologic deficits at various times. Nissl staining revealed morphological improvement after Nogo­A antibody treatment. Sub­organelle structure was preserved as assessed by electron microscopy in model animals post­antibody treatment; neurological function was improved as well (P<0.05), while the apoptosis index was decreased (26.2±9.85 vs. 46.6±12.95%; P<0.05). Hippocampal caspase­3 mRNA and protein, Nogo­A protein levels were significantly decreased after antibody treatment (P<0.05). Hippocampal Nogo­A expression was positively correlated with caspase­3 (Pearson's correlation; r=0.790, P=0.000). Hippocampal GRP78 and Bcl­2 protein levels were higher after antibody treatment than these levels noted in the model animals (P<0.05), while CHOP, caspase­12 and Bax levels were reduced (P<0.05). Nogo­A antibody ameliorates neurological function after restoration of spontaneous circulation (ROSC), possibly by suppressing apoptosis induced by endoplasmic reticulum stress.

Emergence of KRAS p.G13D mutation and acquired resistance to cetuximab in colorectal cancer with vulvar metastasis: A case report.

RATIONALE: Vulvar metastasis of colorectal cancer (CRC) and acquired resistance to cetuximab is a very rare phenomenon. To our knowledge, few cases have been reported in the English literatures. PATIENT CONCERNS: A 55-year-old woman was diagnosed as adenocarcinoma of the rectum and the primary tumor was detected to be Kirsten-RAS (KRAS) wild type. DIAGNOSES: The patient was diagnosed with rectal adenocarcinoma by colonoscopy. Positron emission tomography/computed tomography (PET-CT) revealed multiple lymph node and bone metastases. INTERVENTIONS: The patient received a first-line course of palliative chemotherapy with FOLFOX combined with cetuximab. OUTCOMES: After an initial response, acquired resistance to cetuximab occurred and vulvar metastasis was established by a second biopsy. Further molecular analysis showed that the KRAS mutation was detected in plasma samples and tumor tissues. LESSONS: Vulvar metastasis from CRC is relatively rare and indicates a poor prognosis. Routine physical examinations of cutaneous and subcutaneous may facilitate early detection of metastases and timely intervention of medical technology. Moreover, combining serial tumor biopsy, liquid biopsy, and radiologic imaging could help to define mechanisms of drug resistance and to guide selection of therapeutic strategies.

Preconditioning but not postconditioning treatment with resveratrol substantially ameliorates post­resuscitation myocardial dysfunction through the PI3K/Akt signaling pathway.

Post­resuscitation myocardial dysfunction (PRMD) is a severe complication that arises in patients after cardiac arrest (CA). However, there are no safe or effective treatment strategies that are currently available to treat these patients. In the present study, it was investigated whether resveratrol administration could inhibit myocardial nitrative stress to alleviate PRMD. CA was induced in Sprague­Dawley rats by trans­oesophageal alternating electrical stimulation, followed by cardiopulmonary resuscitation. Rats were then randomly divided into a preconditioning or a postconditioning group. Left ventricular function (+dP/dtmax and ­dP/dtmin) was recorded for 4 h after the return of spontaneous circulation (ROSC), after which the animals were euthanized. Myocardial nitrative stress was analysed using enzyme­linked immunosorbent assay, western blotting and immunohistochemistry. Wortmannin (a PI3K inhibitor) was used to investigate the involvement of the PI3k/Akt signalling pathway in the cardio­protective activity of resveratrol. After ROSC, resveratrol improved PRMD compared to the vehicle control; however, resveratrol administration significantly improved PRMD in the preconditioning group compared to the postconditioning group. Likewise, resveratrol preconditioning significantly decreased the expression of iNOS and nitrotyrosine in rat hearts but did not significantly ameliorate myocardial nitrative stress. Wortmannin partially inhibited the protective effect of resveratrol preconditioning and resulted in the deterioration of cardiac function and increase in iNOS and nitrotyrosine levels. Resveratrol preconditioning could alleviate PRMD by inhibiting myocardial nitrative stress. The PI3K/Akt signalling pathway may be partially involved in the process.

Qiliqiangxin Protects against Renal Injury in Rat with Cardiorenal Syndrome Type I through Regulating the Inflammatory and Oxidative Stress Signaling.

Cardiorenal syndrome (CRS) is a frequently encountered clinical condition when the dysfunction of either the heart or kidneys amplifies the failure progression of the other organ. CRS remains a major global health problem. Qiliqiangxin (QLQX) is a traditional Chinese herbs medication, which can improve cardiac function, urine volume, and subjective symptoms in patients with chronic heart failure. In the present study, we aim to investigate the role of QLQX in the treatment of CRS type I and the possible mechanism through establishment of a rat model of myocardial infarction. Rats in CRS-Q group were orally treated with QLQX daily for 2 weeks or 4 weeks, while in sham group and CRS-C group were treated with saline at the same time. Enzyme-linked immunosorbent assay (ELISA) analysis showed that QLQX significantly reduced the levels of angiotensin II (AngII), brain natriuretic peptides (BNP), creatinine (CRE), cystatin C (CysC), tumor necrosis factor (TNF)-α, interleukin (IL)-6, microalbuminuria (MAU), and neutrophil gelatinase-associated lipocalin (NGAL) in plasma induced by myocardial infarction. Western blot analysis showed that QLQX significantly reduced the expressions of AngII, non-phagocytic cell oxidase (NOX)2, and B-cell lymphoma (Bcl)2 associated X protein (Bax), and increased the expressions of Bcl2 and Angiotensin II Type 1 receptor (ATR) in the kidney as compared with the CRS-C group. Fluorescence microscopy showed that the content of reactive oxygen species (ROS) was significantly reduced in the kidney as compared with the CRS-C group. We also examined the apoptosis level in kidney by using terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) staining, and the result showed that QLQX significantly reduced the apoptosis level in kidney induced by myocardial infarction. Taken together, we suggest that QLQX may be a potentially effective drug for the treatment of CRS by regulating inflammatory/oxidative stress signaling.

Hypoxic Preconditioning Enhances Biological Function of Endothelial Progenitor Cells via Notch-Jagged1 Signaling Pathway.

BACKGROUND Hypoxic preconditioning may be a key influence on functions of endothelial progenitor cells (EPCs). MATERIAL AND METHODS To investigate the role and mechanism of the Notch-Jagged1 pathway on endothelial progenitor cells in hypoxic preconditioning, endothelial progenitor cells were randomly allocated into 5 groups: 1 Normoxic control group; 2 Hypoxic blank group; 3 Hypoxic+25 µM DAPT group; 4 Hypoxic+50 µM DAPT group; 5 Hypoxic+100 µM DAPT group. After reoxygenation, protein and mRNA levels of Jagged1 were measured by Western blot and quantitative RT-PCR. The MTT test was used to assess proliferation. ELISA was used to measure NO and VEGF secretion. RESULTS Hypoxic preconditioning treatment significantly upregulated both protein and mRNA levels of Jagged1 in endothelial progenitor cells. It also enhanced proliferation ability and elevated secretion of NO and VEGF. Furthermore, after blocking the Notch pathway by using DAPT, Jagged1 expression and EP proliferation, migration, and secretion of NO and VEGF were decreased in a dose-dependent manner. CONCLUSIONS Our results suggest the Notch-Jagged1 pathway enhances EPCs proliferation and secretion ability during hypoxic preconditioning.

RTEF-1 protects against oxidative damage induced by H2O2 in human umbilical vein endothelial cells through Klotho activation.

Oxidative stress is a main risk factor of vascular aging, which may lead to age-associated diseases. Related transcriptional enhancer factor-1 (RTEF-1) has been suggested to regulate many genes expression which are involved in the endothelial angiogenesis and vasodilation. However, whether RTEF-1 has a direct role in anti-oxidation and what specific genes are involved in RTEF-1-driven anti-oxidation have not been elucidated. In this study, we found that overexpressing RTEF-1 in H2O2-treated human umbilical vein endothelial cells decreased senescence-associated-ß-galactosidase (SA-ß-gal)-positive cells and G0/G1 cells population. The expressions of p53 and p21 were decreased in H2O2-treated RTEF-1 o/e human umbilical vein endothelial cells. However, specific small interfering RNA of RTEF-1 totally reversed the anti-oxidation effect of RTEF-1 and inhibited RTEF-1-induced decreased p53 and p21 expressions. It demonstrated that RTEF-1 could protect cells from H2O2-induced oxidative damage. In addition, we demonstrated that RTEF-1 could up-regulate Klotho gene expression and activate its promoter. Furthermore, Klotho small interfering RNA significantly blocked RTEF-1-driven endothelial cell protection from H2O2-induced oxidative damage and increased p53 and p21 expressions. These results reveal that RTEF-1 is a potential anti-oxidation gene and can prevent H2O2-induced endothelial cell oxidative damage by activating Klotho.

Management of primary gastric small cell carcinoma in China.

BACKGROUND: Primary gastric small cell carcinomas (GSCCs) are increasingly identified by endoscopy, and account for 15-20% of all gastric neuroendocrine tumors (NETs). GSCCs have the worst prognosis with the highest rate of metastases. PURPOSE: To provide useful information for clinicians and researchers to better manage patients with GSCC, we studied the clinical features of GSCC and explored the corresponding therapies and prognosis. METHODS: A literature search was conducted through PUBMED, EMBASE, CNKI and WanFang Databases using search terms "stomach" or "gastric" and "small cell carcinoma" or "poorly differentiated neuroendocrine carcinoma", for the period 1999 to 2012. And the cases reported were all from China. Relevant articles were identified through manual review. The reference lists of these articles were reviewed to include further appropriate articles. RESULTS: Two hundred and five eligible cases were analyzed. The median age of patients was 62 years, with a male-to-female ratio of 5.4:1. Of the tumors, 53.17% were located in the upper stomach, 25.37% in the mid, 18.54% in the distal stomach, the remaining 2.93% were found in the total stomach. The mean size was 68mm in maximum diameter, with a range of 15-150 mm. Of the one hundred and thirty-five patients, fifty appeared to be pure GSCCs, eighty-five were mixed. The median overall survival time of 195 patients was 18.50 months. The 1-, 2-, and 5-year average survival rates of 142 patients were 66.75%, 37.13%, and 20.15%, respectively. CONCLUSIONS: GSCC is a rare tumor and it is notoriously aggressive with a strong propensity for both regional and distant spread. Therapies including surgical resection, chemotherapy, and local radiotherapy, by itself or in combination with other treatment, have been used to treat GSCCs in China. To identify the most effective treatment modalities for GSCCs, we still need prospective, multicenter, randomized clinical researches.

MAPK-PPARα/γ signal transduction pathways are involved in Chlamydia pneumoniae-induced macrophage-derived foam cell formation.

Chlamydia pneumoniae (C. pneumoniae) is now widely accepted as an independent risk of atherosclerosis development. In this paper, our results showed that C. pneumoniae infection significantly increased the number of foam cells in LDL-treated THP-1 macrophages. C-Jun NH2 terminal kinase (JNK1/2) inhibitor SP600125 and extracellular signal-regulated kinase (ERK1/2) inhibitor PD98059 strongly inhibited C. pneumoniae-induced accumulation of lipid droplet, whereas p38 inhibitor SB203580 had no obvious effect on lipid accumulation. Furthermore, we found that C. pneumoniae not only stimulated the phosphorylation of Mitogen-activated protein kinase (MAPK) including JNK1/2, ERK1/2 and p38 but also down-regulated the expression of peroxisome proliferator-activated receptors (PPARγ and PPARα) at mRNA and protein levels. However, the phosphorylation of JNK1/2, ERK1/2 and p38 MAPK by C. pneumoniae was substantially reversed after PPARγ agonist (rosiglitazone) or PPARα agonist (fenofibrate) treatment while PPARγ inhibitor (GW9662) and PPARα antagonist (MK886) enhanced C. pneumoniae-induced phosphorylation of JNK1/2, ERK1/2 and p38. In addition, we demonstrated that C. pneumoniae-induced PPARγ and PPARα down-regulation were significantly suppressed by JNK1/2 inhibitor (SP600125) and ERK1/2 inhibitor (PD98059), but not p38 inhibitor (SB203580). These results first declare that MAPK-PPARα/γ reciprocal signal pathways are involved in C. pneumoniae, which induces foam cell formation, thus facilitating atherogenesis.

Suppression of telomere-binding protein TPP1 resulted in telomere dysfunction and enhanced radiation sensitivity in telomerase-negative osteosarcoma cell line.

Mammalian telomeres are protected by the shelterin complex that contains the six core proteins POT1, TPP1, TIN2, TRF1, TRF2 and RAP1. TPP1, formerly known as TINT1, PTOP, and PIP1, is a key factor that regulates telomerase recruitment and activity. In addition to this, TPP1 is required to mediate the shelterin assembly and stabilize telomere. Previous work has found that TPP1 expression was elevated in radioresistant cells and that overexpression of TPP1 led to radioresistance and telomere lengthening in telomerase-positive cells. However, the exact effects and mechanism of TPP1 on radiosensitivity are yet to be precisely defined in the ALT cells. Here we report on the phenotypes of the conditional deletion of TPP1 from the human osteosarcoma U2OS cells using ALT pathway to extend the telomeres.TPP1 deletion resulted in telomere shortening, increased apoptosis and radiation sensitivity enhancement. Together, our findings show that TPP1 plays a vital role in telomere maintenance and protection and establish an intimate relationship between TPP1, telomere and cellular response to ionizing radiation, but likely has the specific mechanism yet to be defined.

Suppression of Ku80 correlates with radiosensitivity and telomere shortening in the U2OS telomerase-negative osteosarcoma cell line.

Ku70/80 heterodimer is a central element in the nonhomologous end joining (NHEJ) DNA repair pathway, Ku80 playing a key role in regulating the multiple functions of Ku proteins. It has been found that the Ku80 protein located at telomeres is a major contributor to radiosensitivity in some telomerase positive human cancer cells. However, in ALT human osteosarcoma cells, the precise function in radiosensitivity and telomere maintenance is still unknown. The aim of this study was to investigate the effects of Ku80 depletion in the U2OS ALT cell line cell line. Suppression of Ku80 expression was performed using a vector-based shRNA and stable Ku80 knockdown in cells was verified by Western blotting. U2OS cells treated with shRNA-Ku80 showed lower radiobiological parameters (D0, Dq and SF2) in clonogenic assays. Furthermore, shRNA-Ku80 vector transfected cells displayed shortening of the telomere length and showed less expression of TRF2 protein. These results demonstrated that down-regulation of Ku80 can sensitize ALT cells U2OS to radiation, and this radiosensitization is related to telomere length shortening.

Mechanisms underlying protective effects of trimetazidine on endothelial progenitor cells biological functions against H2O2-induced injury: involvement of antioxidation and Akt/eNOS signaling pathways.

Trimetazidine (TMZ) is a widely used drug exerting cardioprotective effects against ischemic heart disease through a number of mechanisms in conditions of oxidative stress. However, there are few data regarding the effects of TMZ on endothelial lineage, especially endothelial progenitor cells (EPCs). Thus, we sought to investigate whether TMZ could protect EPCs against oxidative stress injury induced by H2O2 (100 µM) and the preliminary mechanisms involved in vitro. The results showed that pretreatment of EPCs with TMZ (10 µM) protected the proliferation, adhesion, migration, and apoptosis of EPCs against H2O2, accompanied by an increase in superoxide dismutase (SOD) activity, a decrease in malonaldehyde (MDA) content, and increases in eNOS, Akt phosphorylation, and NO production. These TMZ-mediated beneficial effects on EPCs could be attenuated by pre-incubation with the Akt inhibitor triciribine. In conclusion, the present study demonstrates that TMZ ameliorated H2O2-induced impairment of biological functions in EPCs with the involvement of antioxidation and Akt/eNOS signaling pathway. These findings suggest that TMZ mediating preservation of EPCs may contribute to its cardioprotective effects on ischemic heart disease.