Interactions between SirT1 and STAT3 in the retinal pigmented epithelium cell / 眼科新进展

Objective To investigate the interactions between histone deacetylas-1 (silent information regulator of transcription 1,SirT1) and signal transducer and activator of transcription 3 (STAT3) following exposure to oxidative stress of retinal pigmented epithelium (RPE) cells through gene knockout and overexpression techniques.Methods RPE cell line was cultured in vitro,followed by addition of H2O2 for inducing oxidative stress.The targeting knockout strategy (siRNA/shRNA) was used for silencing SirT1/STAT3 gene and lentiviral vectors (pRC/CMV STAT3 and PCRC/CMV) were transfected to RPE cells.RT-qPCR and Western blot were used to detect the expression of SirT1/STAT3 due to gene knockout and overexpression and deeply analyze the effects of SirT1/STAT3 on RPE cells exposed to oxidative stress.Results SirT1 activator (resveratrol) significantly reduced the expression of STAT3 mRNA to (3.0 ± 0.2) (P =0.048);and after SifT1 knockout,the expression of STAT3 mRNA in RPE cells was significantly increased to (6.9 ± 1.1) (P =0.025).During the oxidative stress of RPE cells after SifT1 knockout,the expression of STAT3 and phosphorylated STAT3 protein were significantly increased to 0.990 ±0.031 and 0.544 ±0.019,respectively (P =0.000,0.003).With the condition of oxidative stress,the over-expression of STAT3 reduced the SirT1 mRNA expression to 0.42 ± 0.16 (P =0.022),but SifT1 mRNA expression was significantly increased to 2.8 ±0.85 (P =0.015) during STAT3 knockdown.Conclusion SifT1 has a negative effect on the regulation of STAT3 expression during oxidative stress,which suggests that there is an equilibrium mechanism between SirT1 and STAT3 against oxidative stress.

Relationship between expression of decoy receptor 3 and apoptosis in hepatocellular carcinoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the expression of decoy receptor 3 (DcR3) and its relationship with apoptosis and prognosis in hepatocellular carcinoma (HCC).</p><p><b>METHODS</b>The expression of DcR3 protein in 43 cases of HCC and 16 cases of non-cancerous liver (including cirrhotic liver tissue and normal liver tissue adjacent to cavernous hemangioma) was studied by immunohistochemistry (using EnVision method). The status of apoptosis was evaluated by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) technique. Statistic analysis was carried out to assess the correlation between DcR3 expression, apoptotic index (AI) and clinicopathologic parameters.</p><p><b>RESULTS</b>DcR3 protein was expressed in the cytoplasm of HCC cells. The positivity rate of DcR3 in HCC was 74.42% (32/43), which was significantly higher than that in the non-cancerous group (43.75%, P < 0.05). The positivity rate of DcR3 in HCC with metastasis detected within 20 months of diagnosis was 100% (22/22). This was significantly higher than that in HCC without metastasis (52.94%, P < 0.01). The DcR3 expression in HCC also correlated with serum alpha-fetoprotein level (r = 0.444, P < 0.01) and presence of tumor embolus in portal vein (r = 0.414, P < 0.01). However it had no relationship with the patient's age, sex, cirrhotic status, liver capsule invasion, number of tumor nodules and histologic differentiation (P > 0.05). The AI in HCC (0.78 +/- 0.64)% was significantly lower than that in the non-cancerous group [(3.32 +/- 1.81)%, P < 0.01]. The AI in clinical TNM stage I and II tumors (1.03 +/- 0.69)% was significantly higher than that in stage III and IV tumors [(0.52 +/- 0.48)%, P < 0.01]. The AI in HCC without metastasis (1.10 +/- 0.72)% was significantly higher than that in HCC without metastasis [(0.44 +/- 0.27)%, P < 0.05]. The AI correlated with serum alpha-fetoprotein level (r = -0.468, P < 0.01), presence of tumor embolus in portal vein (r = -0.434, P < 0.01) and liver capsule invasion (r = -0.331, P < 0.05). On the other hand, it had no relationship with patient's age, sex, cirrhotic status, number of tumor nodules and histologic differentiation (P > 0.05). The AI in DcR3-positive group (including both HCC and non-cancerous tissues) was significantly lower than that in DcR3-negative group (P < 0.01).</p><p><b>CONCLUSIONS</b>The expression of DcR3 in HCC correlates with apoptosis of tumor cells and may play a crucial role in tumor pathogenesis and progression. DcR3 protein expression and AI may also serve as important biologic indicators in predicting prognosis of HCC.</p>

Expression and role of nitric oxide synthase in the testis and epididymis of Macaca fascicularis / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the expression and the role of nitric oxide synthase (NOS) in the testis and epididymis of macaca fascicularis.</p><p><b>METHODS</b>The immunohistochemical ABC method was used to observe the localization of nitric oxide synthase in the testis and epididymis of the macaca fascicularis.</p><p><b>RESULTS</b>(1) nNOS immunoreactivity was found in the spermatogenic cells of seminiferous tubules, the epithelia of epididymal efferent ducts, sperm and the endothelia of blood vessels; (2) iNOS was expressed in the epididymal efferent duct, the sperm inside the duct, and the myoid cells and endothelia of blood vessels; (3) eNOS immunoreactivity was detected in the interstitial cells of the testis, the epididymal efferent duct, the sperm inside the duct, and the myoid cells and endothelia of blood vessels.</p><p><b>CONCLUSION</b>NOS is extensively expressed in the testis and epididymis of the macaca fascicularis and it may play an important role in such processes as spermatogenesis, sperm maturation and testosterone secretion.</p>

Plasma level of matrix metalloproteinase-9 in patients with acute coronary syndrome and its percutaneous coronary intervention / 第二军医大学学报

Objective: To determine the plasma MMP-9 levels in patients with coronary heart disease before and after percutaneous coronary intervention (PCI) and in healthy controls before and after coronary angiography, so as to assess the value of MMP-9 in evaluating the plaque stability in atherosclerosis. Methods: The plasma MMP-9 levels were determined by ELISA in 29 patients with acute myocardial infarction (AMI), 34 patients with unstable angina (UAP), 27 patients with stable angina (SAP), and 28 healthy controls. Meanwhile, their serum hs-CRP levels were measured by particle-enhanced immunonephelometry. Results: The baseline level of MMP-9 was higher in AMI group (171.30 ng/ ml) than those in SAP (52.00 ng/ml, P<0.01) and control (52.75 ng/ml, P<0.01) groups, and was higher in UAP group (143.55 ng/ml) than those in SAP and the control groups (P<0.05). The serum level of hs-CRP was higher in AMI group (5.260 mg/L) than those in UAP (2.040 mg/L, P<0.01), SAP (1.070 mg/L, P<0.01), and the control (0.550 mg/L, P<0.01) groups, and was higher in UAP group than those in the SAP (P<0.05) and the control groups (P<0.01). The levels of MMP-9 were obviously decreased after operation. The change of MMP-9 (ΔMMP-9) in AMI group (135.40 ng/ ml) was more obvious than those in SAP (29.50 ng/ml, P<0.01) and the control (26.50 ng/ml, P<0.01) groups. ΔMMP-9 in UAP (103.05 ng/ml) group was more obvious than those in SAP and the control groups (P<0.05). The plasma levels of MMP-9 were positively correlated with the levels of hs-CRP; neither MMP-9 nor hs-CRP was correlated with Gensini score or the number of diseased arteries. Conclusion: Plasma levels of MMP-9 and hs-CRP can be used for evaluation of plaque stability in coronary atherosclerosis. The post-PCI decrease of plasma MMP-9 level may be related to the improvements of ischemia and inflammation.