Clinical and functional characterization of a novel KCNJ11 (c.101G > A, p.R34H) mutation associated with maturity-onset diabetes mellitus of the young type 13.

PURPOSE: This study aimed to describe the clinical features, diagnostic and therapeutic course of a patient with MODY13 caused by KCNJ11 (c.101G > A, p.R34H) and how it contributes to the pathogenesis of MODY13, and to explore new therapeutic targets. METHODS: Whole-exome sequencing was used to screen prediagnosed individuals and family members with clinically suspected KCNJ11 mutations. Real-time fluorescence quantitative PCR, western blotting, thallium flux of potassium channels, glucose-stimulated insulin secretion (GSIS), and immunofluorescence assays were used to analyze the regulation of insulin secretion by the KCNJ11 mutant in MIN6 cells. Daily blood glucose levels were continuously monitored for 14 days in the proband using the ambulatory blood glucose meter (SIBIONICS). RESULTS: Mutation screening of the entire exon of the gene identified a heterozygous KCNJ11 (c.101G > A, p.R34H) mutation in the proband and his mother. Cell-based GSIS assays after transfection of MIN6 using wild-type and mutant plasmids revealed that this mutation impaired insulin secretory function. Furthermore, we found that this impaired secretory function is associated with reduced functional activity of the mutant KCNJ11 protein and reduced expression of the insulin secretion-associated exocytosis proteins STXBP1 and SNAP25. CONCLUSION: For the first time, we revealed the pathogenic mechanism of KCNJ11 (c.101G > A, p.R34H) associated with MODY13. This mutant can cause alterations in KATP channel activity, reduce sensitivity to glucose stimulation, and impair pancreatic ß-cell secretory function by downregulating insulin secretion-associated exocytosis proteins. Therefore, oral sulfonylurea drugs can lower blood glucose levels through pro-insulinotropic effects and are more favorable for patients with this mutation.

LncRNA KCNQ1OT1 predicts further cerebral events in patients with transient ischemic attack.

Transient ischemic attack (TIA) poses a great threat of cerebrovascular diseases to a large number of patients, despite its reversible neurological dysfunction. Long non-coding RNAs (lncRNAs) have been proven to play critical roles in the pathophysiological development of cerebrovascular events. Exploring the function of lncRNAs in modulating TIA prognosis would help to develop individualized therapeutics. A total of 231 participants with the first onset of TIA were recruited in the study, including 65 subsequent stroke patients. The expression of lncRNA potassium voltage-gated channel subfamily Q member 1 opposite strand 1 (KCNQ1OT1) was upregulated in patients with recurrent ischemic events after TIA. Additionally, KCNQ1OT1 could be regarded as an independent predictor for subsequent ischemic stroke. The optimal diagnostic value was determined at 1.29 with a sensitivity of 63% and a specificity of 72%. Fewer patients would survive from further ischemic stroke with their KCNQ1OT1 level over 1.29. Furthermore, the expression of KCNQ1OT1 was elevated with a growing serum high-sensitivity C-reactive protein (hs-CRP) level. KCNQ1OT1 might be involved in the regulation of early inflammatory response during recurrence of TIA.

Effect of Impact Velocity and Angle on Impact Wear Behavior of Zr-4 Alloy Cladding Tube.

In the pressurized water reactor nuclear power plant, 316L SS chips were captured by the support grid and continued to affect the Zr-4 cladding tube, causing the fuel rods to wear and perforate. In this work, a 60° acute angle cone of 316L SS was used to simulate the cyclic impact of debris on a Zr-4 alloy tube with different initial impact velocities and impact angles. Results showed that increasing the initial impact velocity will generate a wear debris accumulation layer with a wear-reducing effect, but also promote the extension and expansion of fatigue cracks, resulting in the delamination of Zr-4 alloy tubes. The inclination of the impact angle increases the energy loss. The energy loss rate of the 45° impact is as high as 69.68%, of which 78% is generated by the impact-sliding stage. The normal force is mainly responsible for the wear removal and plastic deformation of Zr-4 alloy tubes. Tangential forces cause severe cutting in Zr-4 alloys and pushes the resulting wear debris away from the contact surfaces.

A synthetic toll-like receptor 7 agonist inhibits porcine reproductive and respiratory syndrome virus replication in piglets.

Toll-like receptor 7 (TLR7) agonists have been shown to exert therapeutic effects against several viruses. However, antiviral potential of TLR7 agonist in inhibiting porcine reproductive and respiratory syndrome virus (PRRSV) infection has not been assessed in vivo. In our previous study, a synthetic TLR7 agonist, SZU101, was confirmed to inhibit PRRSV infection of porcine alveolar macrophages (PAMs). Here, antiviral effects of SZU101 were evaluated in PRRSV-challenged piglets based on assessments of rectal temperature, viremia, gross and microscopic lung lesions, PRRSV-specific antibodies, PRRSV-specific lymphocyte proliferation and serum IFN-ß level. Our results revealed that SZU101 treatment alleviated PRRSV-induced rectal temperature spikes, pulmonary pathologic changes, and serum viral load. Meanwhile, administration of SZU101 led to increased proliferation of PRRSV-specific lymphocytes and serum IFN-ß levels, but did not enhance PRRSV-specific antibody production. These results demonstrate that SZU101 has potential as a therapeutic treatment for PRRS.

Advances in the Role of Endothelial Cells in Cerebral Small Vessel Disease.

Cerebral small vessel disease (CSVD) poses a serious socio-economic burden due to its high prevalence and severe impact on the quality of life of elderly patients. Pathological changes in CSVD mainly influence small cerebral arteries, microarteries, capillaries, and small veins, which are usually caused by multiple vascular risk factors. CSVD is often identified on brain magnetic resonance imaging (MRI) by recent small subcortical infarcts, white matter hyperintensities, lacune, cerebral microbleeds (CMBs), enlarged perivascular spaces (ePVSs), and brain atrophy. Endothelial cell (EC) dysfunction is earlier than clinical symptoms. Immune activation, inflammation, and oxidative stress may be potential mechanisms of EC injury. ECs of the blood-brain-barrier (BBB) are the most important part of the neurovascular unit (NVU) that ensures constant blood flow to the brain. Impaired cerebral vascular autoregulation and disrupted BBB cause cumulative brain damage. This review will focus on the role of EC injury in CSVD. Furthermore, several specific biomarkers will be discussed, which may be useful for us to assess the endothelial dysfunction and explore new therapeutic directions.

HOXC6/8/10/13 predict poor prognosis and associate with immune infiltrations in glioblastoma.

BACKGROUND: Glioblastoma (GBM), characterized by deregulated cell proliferation and immune cells infiltration, is a common and lethal tumor of the central nervous system. Recently, the infiltration of immune cells has attracted attention as a potential novel GBM immunotherapy option. Homeobox C cluster (HOXC) is an evolutionarily conserved family of transcriptional factors that are involved in embryogenesis and tumorigenesis. Nevertheless, the correlations of HOXCs with the prognosis and immune infiltration of GBM remain blurred. METHODS: The RNA-seq data with corresponding clinical characteristics were downloaded from TCGA and GTEx databases. The correlations between HOXCs and clinical characteristics were calculated using univariable and multivariate Cox regression. R language with ggplot2, survminer, survival, GSVA, and pROC packages were employed to analyze the data and present the plots. MethSurv, UALCAN and cBioPortal were employed to evaluate the DNA methylation and mutation status of HOXCs in GBM. We also verified the expression and prognosis of HOXCs by qPCR and immunohistochemistry in a cohort of 36 patients. RESULTS: We identified that HOXC6/8/10/13 were crucial biomarkers for diagnosis and prognostic judgement in GBM. Gene set variation analysis revealed that levels of expression of HOXCs were associated with the infiltration of various immune cells. The qPCR and immunohistochemistry data validated the prognostic values of HOXC6/8/10/13 in GBM. Finally, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that HOXCs might be involved in DNA-binding transcription activator activity and the apelin signaling pathway. CONCLUSION: This research highlights that HOXC6/8/10/13 are involved in the immune infiltrates, also provide potential clinical utility as therapeutic targets in GBM.

Linc00475 promotes the progression of glioma by regulating the miR-141-3p/YAP1 axis.

Glioma is the most prevalent and lethal primary brain tumour. Abundant long non-coding RNAs ( lncRNAs) are aberrant and play crucial roles in the oncogenesis of glioma. The exact functions of linc00475 in glioma remain blurred. Here, we analysed the expression levels of linc00475 by qRT-PCR and discovered that linc00475 was up-regulated in glioma and predicted a poor prognosis in patients with glioma. Besides, inhibiting linc00475 restrained the progression of glioma in vitro and in vivo. Further experiments confirmed that linc00475 regulated the progression of glioma by acting as a sponge for miR-141-3p. Moreover, we detected the binding sites of linc00475 and miR-141-3p, the YAP1- 3'UTR and miR-141-3p by luciferase reporters. The rescue assays confirmed that inhibiting linc00475 restrained the progression of glioma through the miR-141-3p/YAP1 pathway. Collectively, our research demonstrates the key roles of linc00475 in glioma, which could be a promising therapeutic target.

MicroRNA-670 aggravates cerebral ischemia/reperfusion injury via the Yap pathway.

Apoptosis is an important programmed cell death process involved in ischemia/reperfusion injury. MicroRNAs are considered to play an important role in the molecular mechanism underlying the regulation of cerebral ischemia and reperfusion injury. However, whether miR-670 can regulate cell growth and death in cerebral ischemia/reperfusion and the underlying mechanism are poorly understood. In this study, we established mouse models of transient middle artery occlusion and Neuro 2a cell models of oxygen-glucose deprivation and reoxygenation to investigate the potential molecular mechanism by which miR-670 exhibits its effects during cerebral ischemia/reperfusion injury both in vitro and in vivo. Our results showed that after ischemia/reperfusion injury, miR-670 expression was obviously increased. After miR-670 expression was inhibited with an miR-670 antagomir, cerebral ischemia/reperfusion injury-induced neuronal death was obviously reduced. When miR-670 overexpression was induced by an miR-670 agomir, neuronal apoptosis was increased. In addition, we also found that miR-670 could promote Yap degradation via phosphorylation and worsen neuronal apoptosis and neurological deficits. Inhibition of miR-670 reduced neurological impairments after cerebral ischemia/reperfusion injury. These results suggest that microRNA-670 aggravates cerebral ischemia/reperfusion injury through the Yap pathway, which may be a potential target for treatment of cerebral ischemia/reperfusion injury. The present study was approved by the Institutional Animal Care and Use Committee of China Medical University on February 27, 2017 (IRB No. 2017PS035K).

Severe Acute Respiratory Syndrome Coronavirus 2-Induced Neurological Complications.

Our review aims to highlight the neurological complications of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the available treatments according to the existing literature, discussing the underlying mechanisms. Since the end of 2019, SARS-CoV-2 has induced a worldwide pandemic that has threatened numerous lives. Fever, dry cough, and respiratory symptoms are typical manifestations of COVID-19. Recently, several neurological complications of the central and peripheral nervous systems following SARS-CoV-2 infection have gained clinicians' attention. Encephalopathy, stroke, encephalitis/meningitis, Guillain-Barré syndrome, and multiple sclerosis are considered probable neurological signs of COVID-19. The virus may invade the nervous system directly or induce a massive immune inflammatory response via a "cytokine storm." Specific antiviral drugs are still under study. To date, immunomodulatory therapies and supportive treatment are the predominant strategies. In order to improve the management of COVID-19 patients, it is crucial to monitor the onset of new neurological complications and to explore drugs/vaccines targeted against SARS-CoV-2 infection.

STAT6 correlates with response to immune checkpoint blockade therapy and predicts worse survival in thyroid cancer.

Aim: The signal transducer and activator of transcription (STAT) family has been documented. However, the role of STATs in thyroid cancer was not fully studied. Materials & methods: A survival analysis of STATs was performed. The function modulated by STAT6 was examined. The role of STAT6 in cancer immune infiltrates and immune checkpoint blockade molecules was investigated. Results: Only low STAT6 expression correlated with worse survival. STAT6 is involved in cell cycle, cell adhesion, apoptosis and notch signaling pathways. STAT6 was significantly positively associated with immune infiltration of B cells, CD4+ T cells, neutrophils, macrophages, dendritic cells and the immune checkpoint blockade molecules programmed cell death-ligand 1, programmed cell death-ligand 2 and cytotoxic T-lymphocyte-associated protein 4. Conclusion: STAT6 may act as a prognostic biomarker and provide useful information for immunotherapy in thyroid carcinoma.

FKBP5 Exacerbates Impairments in Cerebral Ischemic Stroke by Inducing Autophagy via the AKT/FOXO3 Pathway.

Cerebral ischemic stroke is regarded as one of the most serious diseases in the human central nervous system. The secondary ischemia and reperfusion (I/R) injury increased the difficulty of treatment. Moreover, the latent molecular regulating mechanism in I/R injury is still unclear. Based on our previous clinical study, we discovered that FK506 binding protein 5 (FKBP5) is significantly upregulated in patients, who suffered acute ischemic stroke (AIS), with high diagnostic value. Levels of FKBP5 were positively correlated with patients' neurological impairments. Furthermore, a transient middle cerebral artery occlusion (tMCAO) model of mice was used to confirm that FKBP5 expression in plasma could reflect its relative level in brain tissue. Thus, we hypothesized that FKBP5 participated in the regulation of cerebral I/R injury. In order to explore the possible roles FKBP5 acted, the oxygen and glucose deprivation and reoxygenation (OGD/R) model was established to mimic I/R injury in vitro. FKBP5 expressing levels were changed by plasmid stable transfection. The altered expression of FKBP5 influenced cell viability and autophagy after OGD/R injury notably. Besides, AKT/FOXO3 cascade was involved in the FKBP5-regulating process. In the present study, FKBP5 was verified upregulated in cerebral I/R injury, related to the severity of ischemia and reperfusion injury. Additionally, our analyses revealed that FKBP5 regulates autophagy induced by OGD/R via the downstream AKT/FOXO3 signaling pathway. Our findings provide a novel biomarker for the early diagnosis of ischemic stroke and a potential strategy for treatment.

Iron-Catalyzed Asymmetric Hydrosilylation of Vinylcyclopropanes via Stereospecific C-C Bond Cleavage.

An iron-catalyzed highly anti-Markovnikov selective, enantioselective hydrosilylation of vinylcyclopropanes with PhSiH3 was reported for the preparation of valuable chiral allylic silanes via stereospecific C-C bond cleavage. Simultaneously, difficultly prepared chiral VCPs could be also obtained with moderate to excellent enantioselectivity via this kinetic resolution pathway. The chiral Z-allylic silanes could be converted to various chiral allylic derivatives. A possible mechanism via an iron-silyl species was proposed based on experimental and computational studies.

Knockdown of linc01023 restrains glioma proliferation, migration and invasion by regulating IGF-1R/AKT pathway.

LncRNAs have been proved to be involved in the promotion of glioma cell malignant development. However, the exact roles and molecular mechanisms of linc01023 in glioma remain blurred. In this study, we confirm linc01023 is up-regulated in glioma tissues and cell lines. In addition, elevated linc01023 expression indicates shorter survival times in patients with glioma. Moreover, loss-of-function studies reveal that restoration of linc01023 restrains glioma cell proliferation, migration and invasion by regulating IGF1R/AKT pathway in vitro and in vivo. Collectively, the study indicates that linc01023 plays an oncogenic role in glioma through activation of IGF1R/AKT signal pathway, and it could be a candidate therapeutic target.

KCNQ1OT1 promotes autophagy by regulating miR-200a/FOXO3/ATG7 pathway in cerebral ischemic stroke.

Dysregulation of long noncoding RNAs (lncRNAs) is associated with abnormal development and pathophysiology in the brain. Increasing evidence has indicated that ischemic stroke is becoming the most common cerebral disease in aging populations. The treatment of ischemic stroke is challenging, due in part to ischemia and reperfusion (I/R) injury. In this study, we revealed that potassium voltage-gated channel subfamily Q member 1 opposite strand 1 (KCNQ1OT1) was significantly upregulated in ischemic stroke. Knockdown of KCNQ1OT1 remarkably reduced the infarct volume and neurological impairments in transient middle cerebral artery occlusion (tMCAO) mice. Mechanistically, KCNQ1OT1 acted as a competing endogenous RNA of miR-200a to regulate downstream forkhead box O3 (FOXO3) expression, which is a transcriptional regulator of ATG7. Knockdown of KCNQ1OT1 might inhibit I/R-induced autophagy and increase cell viability via the miR-200a/FOXO3/ATG7 pathway. This finding offers a potential novel strategy for ischemic stroke therapy.

Over-Expressed FEZF1 Predicts a Poor Prognosis in Glioma and Promotes Glioma Cell Malignant Biological Properties by Regulating Akt-ERK Pathway.

FEZ family zinc finger 1 (FEZF1) is an essential transcription factor during olfactory development. In gastrointestinal tumors, FEZF1 plays an oncogenic role through DNA demethylation. However, the role of FEZF1 in the prognosis of human glioma prognosis remains unclear. In this research, we discovered that FEZF1 was significantly increased in glioma tissues in contrast to normal brain tissues (NBTs; P < 0.05). Moreover, the expression of FEZF1 showed a significant correlation with Eastern Cooperative Oncology Group performance status, World Health Organization grade, isocitrate dehydrogenase 1 mutation, over-expression of glial fibrillary acidic protein and 1p19q co-deletion. Furthermore, a high level of FEZF1 in patients with glioma acted as an independent biomarker to predict reduced survival (P = 0.026). In an in vitro experiment, FEZF1 can promote the proliferation, migration, and invasion of glioma cells and inhibit cell apoptosis by activating Akt-ERK pathway. All these findings suggest that FEZF1 acts as a key oncogene and predicts a poor prognosis in glioma.

Artificial Neural Network: A Method for Prediction of Surgery-Related Pressure Injury in Cardiovascular Surgical Patients.

PURPOSE: The aim of this study was to build an artificial neural network (ANN) model for predicting surgery-related pressure injury (SRPI) in cardiovascular surgical patients. DESIGN: Prospective cohort study. SUBJECTS AND SETTING: One hundred forty-nine patients who had cardiovascular surgery were included in the study. This study was conducted in a 1000-bed teaching hospital in Eastern China where 250 to 350 cardiac surgeries are performed each year. METHODS: We performed a prospective cohort study among consecutive patients undergoing cardiovascular surgery between January and December 2015. The ANN model was built based on possible SRPI risk factors. The model performance was tested by a receiver operating characteristic curve and the C-index. A C-index from 0.5 to 0.7 is classified as having low accuracy, 0.7 to 0.9 as having moderate accuracy, and 0.9 to 1.0 as having high accuracy. We also compared the actual SRPI incidences based on the ANN stratification. RESULTS: Thirty-seven of 147 patients developed SRPIs, yielding an incidence rate of 24.8% (95% CI, 18.1-32.6). The C-index was 0.815, which showed the ANN model had a moderate prediction value for SRPI. According to the ANN model, the SRPI predicting incidence ranged from 6.4% to 67.7%. Surgery-related pressure injury incidences were significantly different among 3 risk groups stratified by the ANN (P < .05). CONCLUSION: We established an ANN model that provides moderate prediction of SRPI in patients undergoing cardiovascular surgical procedures. Identification and additional associated factors should be incorporated into the ANN model to increase its predictive ability.

Chronic rhein treatment improves recognition memory in high-fat diet-induced obese male mice.

High-fat (HF) diet modulates gut microbiota and increases plasma concentration of lipopolysaccharide (LPS) which is associated with obesity and its related low-grade inflammation and cognitive decline. Rhein is the main ingredient of the rhubarb plant which has been used as an anti-inflammatory agent for several millennia. However, the potential effects of rhein against HF diet-induced obesity and its associated alteration of gut microbiota, inflammation and cognitive decline have not been studied. In this study, C57BL/6J male mice were fed an HF diet for 8 weeks to induce obesity, and then treated with oral rhein (120 mg/kg body weight/day in HF diet) for a further 6 weeks. Chronic rhein treatment prevented the HF diet-induced recognition memory impairment assessed by the novel object recognition test, neuroinflammation and brain-derived neurotrophic factor (BDNF) deficits in the perirhinal cortex. Furthermore, rhein inhibited the HF diet-induced increased plasma LPS level and the proinflammatory macrophage accumulation in the colon and alteration of microbiota, including decreasing Bacteroides-Prevotella spp. and Desulfovibrios spp. DNA and increasing Bifidobacterium spp. and Lactobacillus spp. DNA. Moreover, rhein also reduced body weight and improved glucose tolerance in HF diet-induced obese mice. In conclusion, rhein improved recognition memory and prevented obesity in mice on a chronic HF diet. These beneficial effects occur via the modulation of microbiota, hypoendotoxinemia, inhibition of macrophage accumulation, anti-neuroinflammation and the improvement of BDNF expression. Therefore, supplementation with rhein-enriched food or herbal medicine could be beneficial as a preventive strategy for chronic HF diet-induced cognitive decline, microbiota alteration and neuroinflammation.

Teasaponin improves leptin sensitivity in the prefrontal cortex of obese mice.

SCOPE: Obesity impairs cognition, and the leptin-induced increase of brain-derived neurotrophic factor (BDNF) and neurogenesis. Tea consumption improves cognition and increases brain activation in the prefrontal cortex. METHODS AND RESULTS: This study examined whether teasaponin, an active ingredient in tea, could improve memory and central leptin effects on neurogenesis in the prefrontal cortex of obese mice, and in vitro in cultured prefrontal cortical neurons. Teasaponin (10 mg/kg, intraperitoneal) for 21 days improved downstream leptin signaling (JAK2 and STAT3), and leptin's effect on BDNF, in the prefrontal cortex of high-fat diet (HFD) fed mice. Prefrontal cortical neurons were cultured with teasaponin and palmitic acid (the most abundant dietary saturated fatty acid) to examine their effects on neurogenesis and BDNF expression in response to leptin. Palmitic acid decreased leptin's effect on neurite outgrowth, postsynaptic density protein 95, and BDNF expression in cultured cortical neurons, which was reversed by teasaponin. CONCLUSION: Teasaponin improved the leptin sensitivity of prefrontal cortical neurons in obese mice or when treated by palmitic acid. This in turn increased BDNF expression and neurite growth. Therefore, teasaponin supplementation may be used to prevent obesity-associated neurodegeneration and improve cognitive function.

[Clinical evaluation of the consistency between two diagnostic criteria for diabetic peripheral neuropathy].

OBJECTIVE: To evaluate the consistency between the clinical diagnostic criteria and the ascertained diagnostic criteria for diabetic peripheral neuropathy (DPN) in the Preventive and Treatment Guidelines of Diabetes in China (2013) and explore an economic, convenient, and accurate approach to DPN diagnosis. METHODS: The patients with type 2 diabetes admitted in our department from April to June, 2014 were examined for nerve conduction velocity, 10 g nylon silk, vibration threshold value, sense of temperature and pain, and ankle reflex. The sensitivity, specificity, positive predictive value, negative predictive value, Youden index, and Kappa value were calculated to assess the diagnostic power of the two diagnostic criteria. RESULTS: Of the 151 patients enrolled, 106 (70.2%) had a diagnosis of DPN consistent with the ascertained diagnostic criteria, as compared to 86 (56.95%) who were diagnosed according to the clinical diagnostic criteria; the latter patients accounted for 81.13% of former cases. The sensitivity, specificity, positive predictive value, negative predictive value, Youden index, and Kappa value of the clinical diagnostic criteria were 80.19%, 97.78%, 98.84%, 67.69%, 77.97%, and 0.69, respectively, which were highly consistent with those of the ascertained diagnostic criteria; the sensitivity to compression showed a poor consistency between the two diagnostic criteria. In the 5 screening tests, the combined test of temperature sensation, vibration perception, and ankle reflex showed the highest AUC value among their different combinations. CONCLUSION: The clinical diagnostic criteria for DPN show good consistency with the ascertained diagnostic criteria, and for patients with clinical symptoms or with only one positive sign, combination of the two diagnostic criteria can achieve the maximum diagnostic power.

[Alterations in reactive oxygen species and dimethylarginine dimethylaminohydrolase-asymmetric dimethyl-arginine system in the process of endothelial cell senescence induced by high glucose].

OBJECTIVE: To investigate the changes in reactive oxygen species (ROS) and dimethyl- arginine dimethylaminohydrolase-asymmetric dimethylarginine (DDAH-ADMA) system in the process of endothelial cell senescence after exposure to high glucose. METHODS: The human umbilical vein endothelial cells (HUVECs) were cultured with different concentrations of glucose, e.g. 5.5 mmol/L (normal level), and high levels as 11.0, 22.0 and 33.0 mmol/L, for 48 hours, respectively. Subsequently, SA-ß-gal staining was used to evaluate senescence of cells. Telomerase activity was detected by polymerase chain reaction-enzyme linked immunosorbent assay (PCR-ELISA). The intracellular ROS level was measured by flow cytometry. The ADMA concentration and DDAH activity were determined with high-performance liquid chromatography. RESULTS: Compared with normal glucose concentration group, after the endothelial cells were treated with high glucose concentration (11.0-33.0 mmol/L) for 48 hours, the number of SA-ß-gal positive cells was increased significantly [(7.00±1.73)%, (12.67±2.03)%, (16.00±2.26)% vs. (4.00±1.33)%, P>0.05, P<0.05, P<0.05] and the telomerase activity was inhibited dramatically [(91.32±4.01)%, (78.44±3.78)%, (56.04±3.35)% vs. 100%, all P<0.05]. The ROS level (mfi) was increased in all high glucose groups (159.84±27.52, 188.99±18.77, 244.56±20.96 vs.117.11±18.76, P<0.05 or P<0.01). At the same time, the ADMA (µmol/L) production was increas ed (0.78±0.14, 0.88±0.18, 1.08±0.15 vs. 0.70±0.12, P>0.05, P<0.05, P<0.05), and DDAH activity was decreased [(91.32±4.01)%, (78.44±3.78)%, (56.04±3.35)% vs.100%, all P<0.05]. CONCLUSION: High glucose can accelerate endothelial cells senescence in dose-dependent manner and the underlying mechanism may be related to an increased oxidative stress and change in DDAH-ADMA system.