Shear Stress Induces Phenotypic Modulation of Vascular Smooth Muscle Cells via AMPK/mTOR/ULK1-Mediated Autophagy.

Phenotypic modulation of vascular smooth muscle cells (VSMCs) is involved in the pathophysiological processes of the intracranial aneurysms (IAs). Although shear stress has been implicated in the proliferation, migration, and phenotypic conversion of VSMCs, the molecular mechanisms underlying these events are currently unknown. In this study, we investigated whether shear stress(SS)-induced VSMC phenotypic modulation was mediated by autophagy involved in adenosine monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR)/Unc-51-like kinase 1 (ULK1) pathway. The results show that shear stress could inhibit the expression of key VSMC contractile genes and induce pro-inflammatory/matrix-remodeling genes levels, contributing to VSMCs phenotypic switching from a contractile to a synthetic phenotype. More importantly, Shear stress also markedly increased the levels of the autophagy marker microtubule-associated protein light chain 3-II (LC3II), Beclin-1, and p62 degradation. The autophagy inhibitor 3-methyladenine (3-MA) significantly blocked shear-induced phenotypic modulation of VSMCs. To further explore the molecular mechanism involved in shear-induced autophagy, we found that shear stress could activate AMPK/mTOR/ULK1 signaling pathway in VSMCs. Compound C, a pharmacological inhibitor of AMPK, significantly reduced the levels of p-AMPK and p-ULK, enhanced p-mTOR level, and finally decreased LC3II and Beclin-1 level, which suggested that activated AMPK/mTOR/ULK1 signaling was related to shear-mediated autophagy. These results indicate that shear stress promotes VSMC phenotypic modulation through the induction of autophagy involved in activating the AMPK/mTOR/ULK1 pathway.

Green synthesis of selenium nanoparticles with extract of hawthorn fruit induced HepG2 cells apoptosis.

CONTEXT: Selenium nanoparticles (SeNPs) have attracted worldwide attention due to their unique properties and potential bioactivities. Considering that hawthorn is both a traditional medicine and a common edible food, hawthorn fruit extract (HE) was chosen as a reductant to prepare SeNPs. OBJECTIVE: SeNPs were synthesized by using an aqueous HE as a reductant and stabilizer. The antitumor activities and potential mechanisms of SeNPs were explored by using a series of cellular assays. MATERIALS AND METHODS: The HE mediated SeNPs (HE-SeNPs) were examined using various characterisation methods. The cytotoxicity was measured against HepG2 cells after treated with 0, 5, 10 and 20 µg/mL of HE-SeNPs for 24 h. Annexin V-FITC/PI staining analysis was performed to observe the apoptosis of HepG2 cells. Additionally, mitochondrial membrane potential (MMP), intracellular reactive oxygen species (ROS) levels were evaluated. Finally, the protein expression levels of caspase-9 and Bcl-2 were identified by Western blot. RESULTS: The mono-dispersed and stable SeNPs were prepared with an average size of 113 nm. HE-SeNPs showed obvious antitumor activities towards HepG2 cells with an IC50 of 19.22 ± 5.3 µg/mL. Results from flow cytometry revealed that both early and total apoptosis rates increased after treating with HE-SeNPs. After cells were treated with various concentrations of HE-SeNPs (5, 10 and 20 µg/mL) for 24 h, the total rate increased to 7.3 ± 0.5, 9.7 ± 1.7 and 19.2 ± 1.6%, respectively. Meanwhile, treatment of HE-SeNPs up-regulated intracellular ROS levels and reduced the MMP. In addition, HE-SeNPs induced the up-regulation of caspase-9 and down-regulation of Bcl-2. DISCUSSION AND CONCLUSIONS: HE-SeNPs induced intracellular oxidative stress and mitochondrial dysfunction to initiate HepG2 cell apoptosis through the mitochondrial pathway. Therefore, HE-SeNPs may be a candidate for further evaluation as a chemotherapeutic agent for human liver cancer.

MiR-29b Downregulation Induces Phenotypic Modulation of Vascular Smooth Muscle Cells: Implication for Intracranial Aneurysm Formation and Progression to Rupture.

BACKGROUND/AIMS: Our previous microarray results identified numerous microRNAs (miRNAs), including miR-29b, that were differentially expressed in the serum of intracranial aneurysm (IA) patients. The current study aimed to investigate whether miR-29b downregulation in IA could promote the phenotypic modulation of vascular smooth muscle cells (VSMCs) involved in the pathogenesis of aneurysm by activating ATG14-mediated autophagy. METHODS: First, the levels of miR-29b and autophagy related genes (ATGs) between IA patients and normal subjects were compared. Next, we modified the level of miR-29b via lentivirus particles in the VSMCs and examined the effects of miR-29b on proliferation, migration, and phenotypic modulation of VSMCs from a contractile phenotype to a synthetic phenotype, as well as the levels of autophagy. Finally, the binding of miR-29b to the 3'UTR of ATG14 mRNA and its effects on ATG14 expression were analysed by a luciferase reporter assay and Western blot, respectively. RESULTS: The level of miR-29b was decreased, and autophagy markers were increased in the IA patients compared to that of the normal subjects. Knockdown of miR-29b significantly promoted VSMCs proliferation and migration and, more importantly, induced the phenotypic modulation associated with autophagy activation, whereas miR-29b overexpression showed the opposite effects. The luciferase reporter assay demonstrated that ATG14 was a functional target gene of miR-29b. Notably, knockdown of ATG14 by siRNA apparently abrogated miR-29b inhibition-mediated phenotypic modulation. CONCLUSION: Downregulation of miR-29b induced VSMCs phenotypic modulation by directly activating ATG14-mediated autophagy, which is associated with the formation, growth and rupture of IAs.

Neuroprotective effects of miR-27a against traumatic brain injury via suppressing FoxO3a-mediated neuronal autophagy.

MicroRNA-27a (miR-27a) has been reported to be a brain-specific miRNA and aberrantly expressed in the brain suffered from traumatic brain injury (TBI). The present study is designed to investigate the potential role and molecular mechanism of miR-27a in the pathogenesis of TBI. The level of miR-27a in brain was manipulated by intracerebroventricular injection of lentiviral-encoding miR-27a before TBI induction. Real-time PCR was used to detected miR-27a and Forkhead box O3a (FoxO3a) levels in the hippocampus. Then, we evaluated the impact of miR-27a overexpression on neurological function, brain edema, lesion volume and neuronal autophagy after TBI. The blinding of miR-27a to the 3'UTR of FoxO3a mRNA and its effects on FoxO3a translation were analyzed by luciferase reporter assay and Western blot. The downregulation of miR-27a and the increase in FoxO3a level were observed in the hippocampus post-TBI. Overexpression of miR-27a significantly attenuated neurological deficits and brain injury, especially suppressed autophagic activation after TBI. Furthermore, we identified that miR-27a directly targeted the FoxO3a 3'UTR region to reduced FoxO3a protein expression. Knockdown of FoxO3a significantly reversed high levels of autophagy-related genes induced by TBI. Taken together, Overexpression of miR-27a may protect against brain injury via suppressing FoxO3a-mediated neuronal autophagy following TBI.

Risk Score for Neurological Complications After Endovascular Treatment of Unruptured Intracranial Aneurysms.

BACKGROUND AND PURPOSE: Procedure-related neurological complications are common after endovascular treatment of unruptured intracranial aneurysms. We aimed to develop a score to quantify individual patient risk. METHODS: We retrospectively analyzed consecutive patients who underwent endovascular treatment for unruptured intracranial aneurysms between January 2012 and September 2015. After excluding those who lost to follow-up and those with fusiform unruptured intracranial aneurysms, included patients were randomly divided into a derivation group (60%) and a validation group (40%). A neurological complication was defined as any transient or permanent increase in the modified Rankin Scale score after aneurysm embolization. A risk score for neurological complications was derived from multivariable logistic regression analyses in the derivation group and validated in the validation group. RESULTS: Overall, 1060 patients were included (636 in the derivation group and 424 in the validation group). The incidence of neurological complications was 5.5% (95% confidence interval, 3.8%-7.4%). A 3-point risk score (S-C-C) was derived to predict neurological complications (size [≥10 mm=1], core areas [yes=1], and cerebral ischemic comorbidity [yes=1]). The incidence of neurological complications varied from 2.2% in 0-point patients to 25.0% in 3-point patients. The score demonstrated significant discrimination (C-statistic, 0.714; 95% confidence interval, 0.624-0.804) and calibration (McFadden R(2), 0.102) in the derivation group. Excellent prediction, discrimination, and calibration properties were reproduced in the validation group. CONCLUSIONS: One in 20 patients will develop neurological complications after endovascular treatment of unruptured intracranial aneurysms. The S-C-C score may be useful for predicting these adverse outcomes based on variables in daily practice.

Spatial, temporal, and spatiotemporal analysis of malaria in Hubei Province, China from 2004-2011.

BACKGROUND: Malaria remains a public health concern in Hubei Province despite the significant decrease in malaria incidence over the past decades. Furthermore, history reveals that malaria transmission is unstable and prone to local outbreaks in Hubei Province. Thus, understanding spatial, temporal, and spatiotemporal distribution of malaria is needed for the effective control and elimination of this disease in Hubei Province. METHODS: Annual malaria incidence at the county level was calculated using the malaria cases reported from 2004 to 2011 in Hubei Province. Geographical information system (GIS) and spatial scan statistic method were used to identify spatial clusters of malaria cases at the county level. Pure retrospective temporal analysis scanning was performed to detect the temporal clusters of malaria cases with high rates using the discrete Poisson model. The space-time cluster was detected with high rates through the retrospective space-time analysis scanning using the discrete Poisson model. RESULTS: The overall malaria incidence decreased to a low level from 2004 to 2011. The purely spatial cluster of malaria cases from 2004 to 2011 showed that the disease was not randomly distributed in the study area. A total of 11 high-risk counties were determined through Local Moran's I analysis from 2004 to 2011. The method of spatial scan statistics identified different 11 significant spatial clusters between 2004 and 2011. The space-time clustering analysis determined that the most likely cluster included 13 counties, and the time frame was from April 2004 to November 2007. CONCLUSIONS: The GIS application and scan statistical technique can provide means to detect spatial, temporal, and spatiotemporal distribution of malaria, as well as to identify malaria high-risk areas. This study could be helpful in prioritizing resource assignment in high-risk areas for future malaria control and elimination.

Neuroprotective effect of ceftriaxone in a rat model of traumatic brain injury.

Traumatic brain injury (TBI) is a leading cause of mortality and disability in children and young adults worldwide. Neurologic impairment is caused by both immediate brain tissue disruption and post-injury cellular and molecular events that worsen the primary neurologic insult. The ß-lactam antibiotic ceftriaxone (CTX) has been reported to induce neuroprotection in animal models of diverse neurologic diseases via up-regulation of GLT-1. However, no studies have addressed the neuroprotective role of CTX in the setting of TBI, and whether the mechanism is involved in the modulation of neuronal autophagy remains totally unclear. The present study was designed to determine the hypothesis that administration of CTX could significantly enhance functional recovery in a rat model of TBI and whether CTX treatment could up-regulate GLT-1 expression and suppress post-TBI neuronal autophagy. The results demonstrated that daily treatment with CTX attenuated TBI-induced brain edema and cognitive function deficits in rats. GLT-1 is down-regulated following TBI and this phenomenon can be reversed by treatment of CTX. In addition, we also found that CTX significantly reduced autophagy marker protein, LC3 II, in hippocampus compared to the TBI group. These results suggest that CTX might provide a new therapeutic strategy for TBI and this protection might be associated with up-regulation of GLT-1 and suppression of neuronal autophagy.

The effects of BMSCs transplantation on autophagy by CX43 in the hippocampus following traumatic brain injury in rats.

Traumatic brain injury (TBI) can initiate a series of complicated pathological events, and induce various types of neuronal cell death including autophagy and apoptosis. Currently, the treatment of TBI is one of the main challenges in neurobiology. In this regard, the administration of bone marrow stromal cells (BMSCs) represents a novel treatment modality for TBI. However, the protective mechanism of BMSCs was unknown in the TBI. The aim of the present study was to assess the effects of BMSCs on connexin 43(CX43) and autophagy in the hippocampus following TBI in rats. A rat model of TBI was created using a modified weight-drop device. Double-membrane structures in the process of autophagy formation were frequently observed in injured brain by electron microscopy. The levels of autophagic pathway associated proteins and CX43 were also detected by western blot analysis. Specifically, immunoblotting results showed that BMSCs treatment after TBI could down-regulate light chain 3 (LC3), Beclin-1 and CX43 expression in the hippocampus. Taken together, our results demonstrated that BMSCs were able to significantly suppress TBI-induced autophagy activity, and the potential mechanism by regulating CX43 levels.

Predictor's analysis of anterior circulation cerebral infarction after the endovascular treatment of anterior communicating artery aneurysms.

BACKGROUND: Despite increasing acceptance of endovascular coiling for treating anterior communicating artery (ACoA) aneurysms, anterior circulation cerebral infarction (ACI) after embolization remains a limitation. With higher incidence, higher morbidity and higher mortality, it is one of the main factors influencing the ACoA aneurysms prognosis. Determining the risk factors leading to ACI after embolization will have clinical significance. Through retrospective case analysis, this study investigated the risk factors related to ACI after embolization in order to provide information to serve the clinical practice. MATERIALS AND METHODS: A retrospective review was performed of patients who had undergone coiling of ACoA aneurysms from 2008 to 2012. All patients had ruptured prior to the completion of embolization. Cases with acute stroke symptoms without alternative diagnoses after embolization were diagnosed as ACI. A total of 32 risk factors such as age, sex, hypertension, diabetes mellitus, modified Fisher grade, Hunt-Hess grade, ventricular hemorrhage, etc. were analyzed using univariate and logistic regression analysis. RESULTS: Univariate analysis showed that negative fluid volume balance (P = 0.041 <0.05) and modified Fisher grade (P = 0.049 <0.05) reached statistical significance, suggesting that they might be risk factors for ACI after embolization. Multiple logistic regression analysis showed that modified Fisher grade was significantly associated with ACI after embolization, suggesting that it was an independent risk factor (odds ratios (OR): 4.968, 95% confidence intervals (CI): 1.013-24.360, P = 0.048). CONCLUSION: Modified Fisher grade is an independent risk factor for ACI after embolization.

A meta-analysis of internal mammary lymph node metastasis in breast cancer patients.

BACKGROUND: Knowing the status of the internal mammary lymph (IML) nodes is important for accurate staging and appropriate selection of subsequent treatment in breast cancer. We conducted a meta-analysis to clarify the rate of IML node metastasis in breast cancer patients and discussed the importance of this finding. METHODS: We retrieved articles from the literature that reported positive rates of IML node metastasis in breast cancer patients. The quality of the selected articles was assessed using the 'Methodological Index for Non-Randomized Studies'. The heterogeneity was tested, and publication bias was assessed using a funnel plot. Finally, the positive rate of IML node metastasis in breast cancer patients was calculated using the random-effects model. RESULTS: 15 articles met the inclusion criteria and a total of 4,248 patients were included in the analysis. Heterogeneity across the studies was statistically significant (p = 0.014); thus, the random-effects model was used and the calculated positive rate of IML node metastasis was 23% (95% confidence interval (CI), 0.21-0.25). CONCLUSIONS: Approximately 23% of the breast cancer patients had IML node metastases, for which the prognosis is generally poor. Accurate staging and integrated treatment are necessary to improve the survival of these patients.

A pivotal role of selective autophagy in mitochondrial quality control: Implications for zinc oxide nanoparticles induced neurotoxicity.

Excessive occupational, medical, and environmental exposure of zinc oxide nanoparticles (ZnONPs) caused its accumulation in the nervous system and raised global concerns over its detrimental effects. However, very few researches had been conducted on the impact of mitochondrial quality control process on central nervous system (CNS) after ZnONPs administration, including mitochondrial fission, fusion, biogenesis, and autophagy. In present study, mitochondrial dysfunction and apoptosis were triggered in ZnONPs-exposed human neuroblastoma SH-SY5Y cells. Upregulation of mitochondrial biogenesis regulator (PGC-1α) and fission proteins (Drp1) and downregulation of fusion proteins (OPA1 and Mfn2) were observed in 3 and 6 µg/mL ZnONPs-treated cells. Meanwhile, loss of mitochondrial dynamics and biogenesis was observed in the severe impaired cells (treated with 12 µg/mL ZnONPs). More, autophagy and mitophagy were significantly activated in ZnONPs-treated cells. The increased Beclin1 and LC3 II proteins, decreases of p62 protein, and activated PINK1/Parkin signaling were quantified. The autophagy agonist (Rapamycin), inhibitor (3-MA), and mitophagy inhibitor (Cyclosporine A, CsA) were employed to verify the roles of autophagy and mitophagy in ZnONPs-treated cells. Consequently, mitochondrial dysfunction and apoptosis were aggravated by the blockage of autophagy and mitophagy. Our research could be used to evaluate the risk assessment of ZnONPs exposure in CNS neurons so as to provide a crucial guideline for their future biological applications.

[The analysis of atrial cells conductivity based on epicardial mapping data of dog].

This paper discusses the law of atrial electrical activity propagation (the timing of signal and the conduction velocity) under the sinus rhythm before and after AF caused by high-frequency electrical stimulation. The paper analyzes how different doses of acetylcholine affect the conductivity of the atrial cells of dogs. This result can also help the diagnoses and treatment of human's AF.

[An adaptive filtering algorithm applied to inhibit the interference from the ventricular during atrial epicardial mapping experiment].

This paper introduces an adaptive filtering algorithm based on the LMS principle to inhibit the ventricular interference in the atrial epicardial mapping experiments.

[The development for real-time sampling and display in epicardial mapping system].

In order to realize real-time sampling and display in 128-channeled Epicardial Mapping System whose sampling frequency is 2 kHz per channel, the article introduces a mapping software and preliminarily validates its practicability. The software is designed in MFC, using multiple-thread technology and buffering and pumping values method.

Rare hand mass: malignant peripheral nerve sheath tumor.

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Effects of nanoparticle size on the interaction between zinc oxide nanoparticles and bovine serum albumin.

Communicated by Ramaswamy H. Sarma.

Selenium nanoparticles fabricated in laminarin polysaccharides solutions exert their cytotoxicities in HepG2 cells by inhibiting autophagy and promoting apoptosis.

Selenium nanoparticles (SeNPs) have been attracting increasing attention as potential cancer therapeutic agents. In the present study, laminarin polysaccharides (LP) decorated selenium nanoparticles (LP-SeNPs) with an average diameter of ca. 60 nm were synthesized. Transmission electron microscope (TEM), laser particle analyzer, UV-visible spectrometer and Energy dispersive X-ray (EDX) spectrometer were applied to characterize the prepared SeNPs. The cytotoxicity, apoptosis, and autophagy were examined using a series of cellular assays. The results revealed that LP-SeNPs exhibited cytotoxicity against HepG2 cells with IC50 value was 23.4 ±â€¯2.7 µM. After cells were treated with various concentrations of LP-SeNPs (10, 20 and 40 µM) for 24h, the total apoptosis rate increased to 17.4 ±â€¯1.6, 20.9 ±â€¯1.3 and 30.9 ±â€¯1.2%, respectively. Additionally, treatment of LP-SeNPs increased the expression of Bax and cleaved caspase-9 but decreased the level of Bcl-2. This suggested that LP-SeNPs induced mitochondria-mediated apoptosis. Further, exposure of cells to LP-SeNPs for 12 h induced the upregulation of LC3-II and p62. Treatment of chloroquine (CQ), the inhibitors of the autophagosome, resulted in further accumulation of p62 and LC3-II. These results demonstrated that LP-SeNPs induced the activation of early autophagy, but blocked the late phase of autophagy. Inhibition of late phase of autophagy resulted in the damaged organelles cannot be cleared and aggravating apoptosis. In conclusion, these results indicated that LP-SeNPs exerted its cytotoxicity in HepG2 cells by inhibiting autophagy and inducing apoptosis.

Cerebral Venous Malformations in a Chinese Population: Clinical Manifestations, Radiological Characteristics, and Long-Term Prognosis.

OBJECTIVE: We elucidated the clinical and radiological characteristics and analyzed the risk factors for hemorrhage and poor outcomes of cerebral venous malformations (CVMs) in a northern Chinese population. METHODS: We included 60 consecutive patients with CVM patients in Beijing Tiantan Hospital from January 2011 to February 2018. The clinical manifestations, radiological characteristics, management, and outcomes were elucidated and analyzed. The patients were followed up for 5-64 months (median, 26). Poor outcomes included repeat bleeding, secondary infarction, severe disability (modified Rankin scale score ≥3), and death. RESULTS: Infratentorial CVMs were more prone to intracranial hemorrhage (75% vs. 28.6%; P < 0.001), dizziness (37.5% vs. 10.7%; P = 0.017), and focal neurological deficits (65.6% vs. 25%; P = 0.002) than were supratentorial CVMs. Supratentorial CVMs were more prone to seizure (32.1% vs. 0%; P = 0.001) than were infratentorial CVMs. Multivariate logistic regression revealed that the major risk factors for intracranial hemorrhage in CVMs were infratentorial lesions (P = 0.003) and complicated cavernous angiomas (P = 0.016). Compared with conservative treatment, resection of hematoma or cavernous angiomas with CVM preservation did not increase the risk of poor outcomes (P = 0.646). However, CVM resection significantly increased that risk (odds ratio, 44.0; P = 0.003). CONCLUSIONS: Our results have shown that conservative treatment of CVMs results in a relatively good prognosis. For those complicated by hemorrhage or cavernous angiomas requiring surgical interventions, the integrity of the CVM should be preserved, irrespective of the treatment. In exceptional cases, before CVM resection, the CVM drainage should be comprehensively evaluated.

Suppression of FoxO3a attenuates neurobehavioral deficits after traumatic brain injury through inhibiting neuronal autophagy.

Traumatic brain injury (TBI) is a serious insult that frequently leads to neurological impairments. Forkhead box O (FoxO) 3a, as transcription factor, has been confirmed to modulate autophagic process. Moreover, FoxO3a is expressed throughout the brain including the hippocampus. However, the role of FoxO3a in the pathophysiology of TBI is unclear. The present study is designed to investigate whether FoxO3a has the neuroprotective effects on rats subjected to TBI, and further to explore the potential molecular mechanisms. Thus, a rat model of TBI was created by using a modified weight-drop device to mimic the insults of TBI. The results showed that FoxO3a was significantly increased in the serum of patients with TBI as well as in experimental animals. Furthermore, our data also demonstrated that TBI stimulated the translocation of FoxO3a from the cytosol to the nucleus. Additionally, we found that knockdown of FoxO3a by siRNA silencing significantly improved neurobehavioral dysfunctions and conferred a better neuroprotective effects after TBI, evidenced by promoting motor behavioral recovery, attenuating learning and memory impairments, and partially reversing neuronal damage in the hippocampus. To further investigate the molecular mechanisms underlying this neuroprotection, we identified that nuclear accumulation of Foxo3a could induce highly expression of autophagy pathway genes including LC-3, Beclin-1, p62, ATG12, and ATG14, and finally initiate neurological impairments. Interestingly, silencing FoxO3a by siRNA remarkably inhibited the induction of neuronal autophagy after TBI, and activated autophagy was closely related to TBI-induced neurological deficits. Taken together, these findings indicated that FoxO3a knockdown conferred neuroprotective effects after TBI through inhibiting the activation of neuronal autophagy.

miR-23b improves cognitive impairments in traumatic brain injury by targeting ATG12-mediated neuronal autophagy.

Dysregulated microRNAs (miRNAs) have been reported to involve in the pathophysiological process of traumatic brain injury (TBI), and modulate autophagy-related genes (ATGs) expression. Our previous studies showed that neuronal autophagy was activated in the injury hippocampus post- TBI and associated with neurological and cognitive impairments. The present study was designed to investigate the possible role of miR-23b in TBI-induced cognitive impairments. We found the overexpression of miR-23b conferred a better neuronprotective effects after TBI by decreasing lesion volume, alleviating brain edema, inhibiting neuron apoptosis and attenuating long-term neurological deficits, and most interestingly, improving cognitive impairments. To further explore the molecular underlying this neuronprotection, we evaluated autophagic activity and ATG12 expression in the injury hippocampus CA1 region. The results identified that miR-23b directly targeted to the 3'UTR region of ATG12 mRNA to suppress the activation of neuronal autophagy by a dual-luciferase reporter system. Notably, overexpression of ATG12 abrogated the neuronprotective effects of miR-23b on TBI-induced neurological and cognitive impairments. Taken together, these date revealed inhibition of ATG12-mediated autophagic activity by miR-23b overexpression might be involve in cognitive improvement after TBI, indicating that miR-23b might be a potential therapeutic target for TBI.