Effect of propofol preconditioning on endoplasmic reticulum stress induced by hypoxia-reoxygenation in HEPG2 cells / 中华麻醉学杂志

Objective To evaluate the effect of propofol preconditioning on endoplasmic reticulum stress induced by hypoxia-reoxygenation (H/R) in HEPG2 cells.Methods HEPG2 cells were randomly divided into 4 groups using a random number table:control group (group C),propofol group (group P),H/R group and H/R + propofol preconditioning group (group PP).In group C,the cells were cultured routinely for 42 h.In group H/R,after being cultured routinely for 6 h,the cells were exposed to 1％ O2 + 5％ CO2 + 94％ N2 for 12 h followed by 12 h reoxygenation.In group PP,the cells were cultured for 6 h in the culture medium containing propofol 10 μmol/L (final concentration),and then H/R was induced.The cell viability was detected by MTT assay.The expression of immunoglobulin heavy chain-binding protein (BIP),C/EBP homologous protein (CHOP) and activated caspase-3 was determined by Western blot.The expression of BIP,CHOP and caspase-3 mRNA was determined by RT-PCR.Results Compared with group C,the cell viability was significantly decreased,and the expression of BIP,CHOP and activated caspase-3 protein and mRNA was up-regnlated in H/R and PP groups,and no significant changes were found in the parameters mentioned above in group P.Compared with group H/R,the cell viability was significantly increased,and the expression of BIP,CHOP and activated caspase-3 protein and mRNA was down-regulated in PP group.Conclusion Propofol preconditioning can promote the cell proliferation and attenuate H/R injury to HEPG2 cells through inhibiting endoplasmic reticulum stress.

Effect of propofol pretreatment on endoplasmic reticulum stress-mediated apoptosis during focal cerebral ischemia-reperfusion in rats / 中华麻醉学杂志

Objective To evaluate the effect of propofol on the endoplasmic reticulum stress-mediated apoptosis during focal cerebral ischemia-reperfusion (I/R) in rats.Methods Eighty adult male Sprague-Dawley rats,weighing 240-280 g,were randomly divided into 4 groups (n =20 each):shame operation group (group S) ; focal cerebral I/R group (group FCIR); propofol pretreatment group (group P); intralipid pretreatment group (group Ⅰ).Focal cerebral I/R was induced by 4 h middle cerebral artery occlusion followed by reperfusion.Propofol was infused at a rate of 12 mg· kg-1 · h-1 starting from 30 min before ischemia until 15 min of ischemia in group P,while intralipid was given instead of propofol in group I.Neurological deficit scores (NDSs) were measured at 6 h of reperfusion in 10 rats chosen from each group and the rats were then sacrificed.Their left brains were removed for determination of brain water content.The left 10 rats were sacrificed and their brains were immediately removed for determination of the expression of C/EBP homologous protein (CHOP),Bcl-2,and activated caspase-3 in the left hippocampi by Western blot.Results Compared with group S,NDSs and brain water content were significantly increased,the expression of CHOP and activated caspase-3 was up-regulated,and the expression of Bcl-2 was down-regulated in group FCIR,NDSs was increased in group P (P ＜ 0.05).Compared with group FCIR,NDSs and brain water content were significantly decreased,the expression of CHOP and activated caspase-3 was down-regulated,and the expression of Bcl-2 was up-regulated in group P,and no significant change was found in each parameter in group Ⅰ (P ＞ 0.05).Conclusion Propofol can reduce focal cerebral I/R injury through inhibition of the endoplasmic reticulum stress-mediated apoptosis in rats.

The potential of osteopontin as a therapeutic target for human colorectal cancer.

OBJECTIVE: Osteopontin (OPN), a phosphorylated glycoprotein, is involved in tumor progression and metastasis. Previously, we have reported that high OPN mRNA expression level possessed clinicopathological or prognostic significance in human colorectal cancer (CRC). The aim of this study is to investigate whether OPN can serve as a novel molecular target for CRC therapy. MATERIAL AND METHODS: Western Blot assay was performed to detect the expression of OPN protein in 18 CRC and corresponding nontumor colon tissue samples. RNA interference (RNAi) was employed to knockdown endogenous OPN expression in CRC cell line (LoVo). MTT, colony formation, and tumorigenicity assays were performed to analyze the effect of OPN downregulation on the in vitro and in vivo proliferation of CRC cells. Wound healing and Matrigel invasion assays were performed to analyze the effect of OPN downregulation on migration and invasion of CRC cells. A clonogenic cell survival assay after radiation was performed to analyze the effect of OPN downregulation on the radiosensitivity of CRC cells. RESULTS: The relative level of OPN protein expression in CRC tissues was significantly higher than that in corresponding nontumor colon tissues (P < 0.05). We found that RNAi-mediated OPN downregulation could inhibit not only in vitro proliferation but also in vivo tumorigenicity of CRC cells. In addition, OPN downregulation could suppress in vitro invasion capacity and enhance in vitro radiosensitivity of CRC cells, which might be associated with decreased levels of MMP-2 and -9 expression. CONCLUSION: RNAi-targeting OPN could inhibit proliferation, invasion and enhance radiosensitivity of human CRC cells. Therefore, OPN could serve as a novel molecular target for gene therapy of CRC.

Clinical significance of the upregulated osteopontin mRNA expression in human colorectal cancer.

OBJECTIVE: Osteopontin (OPN) is a phosphorylated glycoprotein which is associated with tumor progression, development, and metastasis. Recently, it has been reported that OPN is highly upregulated in a variety of human malignancies. The aim of this study is to investigate the clinical significance of OPN mRNA expression in colorectal cancer (CRC). MATERIAL AND METHODS: Conventional reverse transcription polymerase chain reaction (RT-PCR) and Western blot assays were performed to detect the expression of OPN mRNA and protein in human CRC cell lines and normal cell line. Real-time quantitative RT-PCR assay was performed to analyze the expression of OPN mRNA in 82 CRC tissue samples and corresponding non-tumor tissues. Immunohistochemistry was also performed to detect the expression of OPN protein in above tissues. Finally, the correlation between the status of OPN mRNA expression and clinicopathological factors and clinical outcome was evaluated. RESULTS: Compared with normal human intestinal epithelial cell line, human CRC cell lines showed high level of OPN gene expression at both transcriptional and translational levels. Moreover, the results of real-time quantitative RT-PCR and immunohistochemistry showed that the expression levels of OPN mRNA and protein in tumor tissues were significantly higher than those in the corresponding non-tumor tissues (P < 0.001). The expression level of OPN mRNA was significantly correlated with lymph node metastasis, lymphatic or venous invasion, and TNM stage (P = 0.0033, 0.0061, 0.0008, and 0.0012, respectively). Moreover, we also observed that the disease-free and overall survival rates in patients with high OPN mRNA expression were significantly shorter than those in patients with low OPN mRNA expression (P = 0.0047 and 0.0125). Additionally, the status of OPN mRNA expression was an independent prognostic factor for the prognosis of CRC patients (P = 0.008; RR, 2.775; 95% confidence interval, 2.334-3.811). CONCLUSION: OPN might play an important role in CRC progression and the status of OPN mRNA expression could be a novel prognostic molecular marker for CRC patients.

Prognostic role of myeloid cell leukemia-1 protein (Mcl-1) expression in human gastric cancer.

BACKGROUND: Myeloid cell leukemia-1 protein (Mcl-1), an anti-apoptotic member of Bcl-2 family, has been reported to be correlated with tumor progression. The purpose of this study was to establish the prognostic value of Mcl-1 expression in human gastric cancer. METHODS: Western blot assay was performed to detect the expression of Mcl-1 protein in human gastric cancer cell lines and tissues, while Mcl-1 expression in resected gastric cancer tissue samples was analysed by immunohistochemistry. RESULTS: The level of Mcl-1 protein expression in gastric cancer cell lines was significantly higher than that in gastric mucosa epithelial cell line. Moreover, the expression level of Mcl-1 protein was significantly higher in gastric cancer tissues than corresponding noncancerous tissues. Expression was correlated with T classification (P = 0.003), metastasis (P = 0.001), clinical stage (P = 0.010), and venous invasion (P = 0.004). Patients with high Mcl-1 expression showed poorer 5-year overall survival than patients with low Mcl-1 expression (P = 0.012; log-rank test). Further univariate and multivariate analysis suggested that high Mcl-1 expression was an independent prognostic marker for the disease. CONCLUSION: Mcl-1 is highly upregulated in gastric cancer and high Mcl-1 expression is correlated with a poor prognosis in gastric cancer patients. Thus, Mcl-1 can be utilized as an independent prognostic factor.

Effects of synthesized peptide S247 on the activation of p38MAPK during ventilator-induced lung injury / 中华急诊医学杂志

Objective To study the effect of synthesized peptide S247 on the activation of p38MAPK of ventilator- induced lung injury.Methods Thirty healthy male SD rats were divided into group A,group B,group C,n 10.All rats were performed with mechanical ventilation,group A with tidal volume(V_T)8 ml/kg,breathing rate(p)80/min;group B with tidal volume(V_T)40 ml/kg,breathing rate(p)=80/min;group C with tidal volume(V_T)40 ml/kg,breathing rate(p)80/min.The rats in group C were intraperitoneally injected with synthesized peptide S247(100 mg/kg)once a day for a week.The time of ventilation in all groups was two hours.Rats were sacrificed after the experiment was finished. The lung lavage liquid and lung tissue were collected and stored with correct methods.The measured indexes included lung pathology change,total protein,WBC,MPO and MIP-2.The expression of p38 and p-p38 were measured by Western Blot in lung tissue.Results Compared with group A,total protein,WBC,MPO,MIP-2 and p-p38 significantly increased in group B;compared with group B,total protein,WBC,MPO,MIP-2 and p-p38 significandy decreased in group C. Conclusion Synthesized peptide S247 significantly inhibited the activation of p38 and relieved the degree of ventilator induced lung injury.

The expressions of rat ?-defensin-2 gene and protein with ventilator-associated pneumonia in different ages / 中国医师杂志

Objective To evaluate the expression of ?-defensin-2(BD-2) gene and protein with ventilator-associated pneumonia(VAP) in the old and grown rats.Methods Fifty-eight normal healthy Sprague-Dawley rats were divided into the old group(400～460 g,15～18 months,n=29) and grown group(280～320 g,4～6 months,n=29).Each rat received ventilation(VT=12 ml/kg) through tracheal tube for 24h and was challenged intra-tracheally with Pseudomonas aeruginosa(0.2 ml).The mRNA and protein levels of BD-2 were detected by RT-PCR and Western blot analysis respectively. Results Compared with the grown group,the rats had more severe interstitial pulmonary edema in the old group.There was no dominant difference in BD-2 mRNA and protein expression between the grown group and old group within 3 h,but BD-2 expressions in the grown group were significantly higher at 3 h,6 h,12 h,1 d,2 d and 3 d than those in the old group(P