547 research outputs found
Sevoflurane induces ho-1-mrna expression by regulating P13K/Akt/P70S6K signaling pathway and affects neuronal apoptosis
Purpose: To determine the effect of sevoflurane (SE) on neuronal apoptosis, and the mechanism involved.Methods: Sixty healthy male Sprague-Dawley rats were assigned to control, model and SE groups. Sham surgery was performed in control group, while middle cerebral artery infarction (MCAO) was established in model group. The expression of HO-1 mRNA was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Apoptosis, autophagy and protein content of P13K/Akt/P70S6K signaling pathway were assessed by Western blot assay.Results: Apoptosis was significantly lower in SE rats, relative to model rats. There were markedly higher protein levels of LC3 II / I, beclin-1, bad, Bcl-2 and caspase-3 in model and SE groups than in control rats (p < 0.05). The HO-1 mRNA was significantly up-regulated in model and SE groups, relative to controls, but it was significantly up-regulated in SE group, relative to model rats (p < 0.05). The expression levels of phosphorylated proteins of the P13K/Akt /P70S6K signal-related proteins in model and SE groups were significantly up-regulated, relative to control, but elevated in SE mice, when compared to model mice (p < 0.05).Conclusion: SE improves the behavior of MCAO rats, reduces cerebral infarction, and inhibits apoptosis and autophagy of nerve cells by regulating autophagy and apoptosis-related proteins through a mechanism that may be related to the induction of HO-1-mRNA expression by regulating P13K/Akt /P70S6K signal pathway. This provides new insights for the development of anti-neuronal apoptosis drugs
Biological Activities of Chinese Propolis and Brazilian Propolis on Streptozotocin-Induced Type 1 Diabetes Mellitus in Rats
Propolis is a bee-collected natural product and has been proven to have various bioactivities. This study tested the effects of Chinese propolis and Brazilian propolis on streptozotocin-induced type 1 diabetes mellitus in Sprague-Dawley rats. The results showed that Chinese propolis and Brazilian propolis significantly inhibited body weight loss and blood glucose increase in diabetic rats. In addition, Chinese propolis-treated rats showed an 8.4% reduction of glycated hemoglobin levels compared with untreated diabetic rats. Measurement of blood lipid metabolism showed dyslipidemia in diabetic rats and Chinese propolis helped to reduce total cholesterol level by 16.6%. Moreover, oxidative stress in blood, liver and kidney was improved to various degrees by both Chinese propolis and Brazilian propolis. An apparent reduction in levels of alanine transaminase, aspartate transaminase, blood urea nitrogen and urine microalbuminuria-excretion rate demonstrated the beneficial effects of propolis in hepatorenal function. All these results suggested that Chinese propolis and Brazilian propolis can alleviate symptoms of diabetes mellitus in rats and these effects may partially be due to their antioxidant ability
Differential responses to genotoxic agents between induced pluripotent stem cells and tumor cell lines
Given potential values of induced pluripotent stem (iPS) cells in basic biomedical research and regenerative medicine, it is important to understand how these cells regulate their genome stability in response to environmental toxins and carcinogens. The present study characterized the effect of Cr(VI), a well-known genotoxic agent and environmental carcinogen, on major molecular components of DNA damage response pathways in human iPS cells. We compared the effect of Cr(VI) on human iPS cells with two established cell lines, Tera-1 (teratoma origin) and BEAS-2B (lung epithelial origin). We also studied the effect of hydrogen peroxide and doxorubicin on modulating DNA damage responses in these cell types. We demonstrated that ATM and p53 phosphorylation is differentially regulated in human iPS cells compared with Tera-1 and BEAS-2B cells after exposure to various genotoxic agents. Moreover, we observed that inhibition of CK2, but not p38, promotes phosphorylation of p53(S392) in iPS cells. Combined, our data reveal some unique features of DNA damage responses in human iPS cells
Characteristics of High Risk People with Cardiovascular Disease in Chinese Rural Areas: Clinical Indictors, Disease Patterns and Drug Treatment
Background and Aims: Current cardiovascular disease (CVD) prevention is based on diagnosis and treatment of specific disease. Little is known for high risk people with CVD at the community level. In rural China, health records of all residents were established after the recent health reforms. This study aims to describe the characters of the rural population with high CVD risk regarding their clinical indicators, disease patterns, drug treatment and adherence. Methods and Results: 17042 (87%) of all the 19500 rural residents in the two townships had valid health records in 2009. We employed a validated tool, the Asian Equation, to screen 8182 (48%) resident health records of those aged between 40-75 years in 2010. Those who were identified with a CVD risk of 20% or higher were selected for a face-to-face questionnaire survey regarding their diagnosed disease and drug treatment. 453 individuals were identified as high risk of CVD, with an average age of 53 years, 62% males, 50% smoking rate and average systolic blood pressure of 161 mmHg. 386 (85%) participated in the survey, while 294 (76%) were diagnosed with and 88 (23%) were suspects of CVD, hypertension, diabetes or hyperlipidaemia. 75 (19%) took drug regularly and 125 (32%) either stopped treatment or missed drugs. The most often used drugs were calcium channel blockers (20%). Only 2% used aspirins and 0.8% used statins. The median costs of drugs were 17 RMB (USD2.66) per month. Conclusion: The majority of the high risk population in our setting of rural China had already been diagnosed with a CVD related disease, but very few took any drugs, and less still took highly effective drugs to prevent CVD. A holistic strategy focused on population with high risk CVD and based on the current China public health reform is suggested in the context of primary care. Β© 2013 Wei et al.published_or_final_versio
Loss of miR-638 in vitro promotes cell invasion and a mesenchymal-like transition by influencing SOX2 expression in colorectal carcinoma cells
BACKGROUND: Colorectal carcinoma (CRC) is a major cause of cancer mortality. The aberrant expression of several microRNAs is associated with CRC progression; however, the molecular mechanisms underlying this phenomenon are unclear. METHODS: miR-638 and SRY-box 2 (SOX2) expression levels were detected in 36 tumor samples and their adjacent, non-tumor tissues from patients with CRC, as well as in 4 CRC cell lines, using real-time quantitative RT-PCR (qRT-PCR). SOX2 expression levels were detected in 90 tumor samples and their adjacent tissue using immunohistochemistry. Luciferase reporter and Western blot assays were used to validate SOX2 as a target gene of miR-638. The regulation of SOX2 expression by miR-638 was assessed using qRT-PCR and Western blot assays, and the effects of exogenous miR-638 and SOX2 on cell invasion and migration were evaluated in vitro using the HCT-116 and SW1116 CRC cell lines. RESULTS: We found that miR-638 expression was differentially impaired in CRC specimens and dependent on tumor grade. The inhibition of miR-638 by an antagomiR promoted cell invasion and a mesenchymal-like transition (lamellipodium stretching increased and cell-cell contacts decreased, which was accompanied by the suppression of the epithelial cell marker ZO-1/E-cadherin and the upregulation of the mesenchymal cell marker vimentin). A reporter assay revealed that miR-638 repressed the luciferase activity of a reporter gene coupled to the 3β²-untranslated region of SOX2. miR-638 overexpression downregulated SOX2 expression, and miR-638 inhibition upregulated SOX2 expression. Moreover, miR-638 expression levels were correlated inversely with SOX2 mRNA levels in human CRC tissues. The RNAi-mediated knockdown of SOX2 phenocopied the invasion-inhibiting effect of miR-638; furthermore, SOX2 overexpression blocked the miR-638-induced CRC cell transition to epithelial-like cells. CONCLUSIONS: These results demonstrate that the loss of miR-638 promotes invasion and a mesenchymal-like transition by directly targeting SOX2 in vitro. These findings define miR-638 as a new, invasion-associated tumor suppressor of CRC
Methylcap-Seq Reveals Novel DNA Methylation Markers for the Diagnosis and Recurrence Prediction of Bladder Cancer in a Chinese Population
PURPOSE: There is a need to supplement or supplant the conventional diagnostic tools, namely, cystoscopy and B-type ultrasound, for bladder cancer (BC). We aimed to identify novel DNA methylation markers for BC through genome-wide profiling of BC cell lines and subsequent methylation-specific PCR (MSP) screening of clinical urine samples. EXPERIMENTAL DESIGN: The methyl-DNA binding domain (MBD) capture technique, methylCap/seq, was performed to screen for specific hypermethylated CpG islands in two BC cell lines (5637 and T24). The top one hundred hypermethylated targets were sequentially screened by MSP in urine samples to gradually narrow the target number and optimize the composition of the diagnostic panel. The diagnostic performance of the obtained panel was evaluated in different clinical scenarios. RESULTS: A total of 1,627 hypermethylated promoter targets in the BC cell lines was identified by Illumina sequencing. The top 104 hypermethylated targets were reduced to eight genes (VAX1, KCNV1, ECEL1, TMEM26, TAL1, PROX1, SLC6A20, and LMX1A) after the urine DNA screening in a small sample size of 8 normal control and 18 BC subjects. Validation in an independent sample of 212 BC patients enabled the optimization of five methylation targets, including VAX1, KCNV1, TAL1, PPOX1, and CFTR, which was obtained in our previous study, for BC diagnosis with a sensitivity and specificity of 88.68% and 87.25%, respectively. In addition, the methylation of VAX1 and LMX1A was found to be associated with BC recurrence. CONCLUSIONS: We identified a promising diagnostic marker panel for early non-invasive detection and subsequent BC surveillance
Silencing SARS-CoV Spike protein expression in cultured cells by RNA interference
AbstractThe severe acute respiratory syndrome (SARS) has been one of the most epidemic diseases threatening human health all over the world. Based on clinical studies, SARS-CoV (the SARS-associated coronavirus), a novel coronavirus, is reported as the pathogen responsible for the disease. To date, no effective and specific therapeutic method can be used to treat patients suffering from SARS-CoV infection. RNA interference (RNAi) is a process by which the introduced small interfering RNA (siRNA) could cause the degradation of mRNA with identical sequence specificity. The RNAi methodology has been used as a tool to silence genes in cultured cells and in animals. Recently, this technique was employed in anti-virus infections in human immunodeficiency virus and hepatitis C/B virus. In this study, RNAi technology has been applied to explore the possibility for prevention of SARS-CoV infection. We constructed specific siRNAs targeting the S gene in SARS-CoV. We demonstrated that the siRNAs could effectively and specifically inhibit gene expression of Spike protein in SARS-CoV-infected cells. Our study provided evidence that RNAi could be a tool for inhibition of SARS-CoV
Curdlan Prevents the Cognitive Deficits Induced by a High-Fat Diet in Mice via the Gut-Brain Axis
A high-fat (HF) diet is a major predisposing factor of neuroinflammation and cognitive deficits. Recently, changes in the gut microbiota have been associated with neuroinflammation and cognitive impairment, through the gut-brain axis. Curdlan, a bacterial polysaccharide widely used as food additive, has the potential to alter the composition of the microbiota and improve the gut-brain axis. However, the effects of curdlan against HF diet-induced neuroinflammation and cognitive decline have not been investigated. We aimed to evaluate the neuroprotective effect and mechanism of dietary curdlan supplementation against the obesity-associated cognitive decline observed in mice fed a HF diet. C57Bl/6J male mice were fed with either a control, HF, or HF with curdlan supplementation diets for 7 days (acute) or 15 weeks (chronic). We found that acute curdlan supplementation prevented the gut microbial composition shift induced by HF diet. Chronic curdlan supplementation prevented cognitive declines induced by HF diet. In addition, curdlan protected against the HF diet-induced abnormities in colonic permeability, hyperendotoxemia, and colonic inflammation. Furthermore, in the prefrontal cortex (PFC) and hippocampus, curdlan mitigated microgliosis, neuroinflammation, and synaptic impairments induced by a HF diet. Thus, curdlan-as a food additive and prebiotic-can prevent cognitive deficits induced by HF diet via the colon-brain axis
- β¦