Protect effect of Delphinidin on light induced oxidative damage of retina / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate the mechanism of Delphinidin(Dp)in protecting retinal against light induced oxidative damage.<p>METHODS: All 661W photosensitive cells were treated with 2 000Lx light(48h)and/or different concentrations of Dp(5, 10, 20μmol/L, 24h). Cell activity, intracellular LDH activity, TBARS content and antioxidant enzymes(SOD, GSH-Px, GST)activity were determined respectively. After the healthy SD rats were treated with 3 000 Lx light(24h)and/or Dp \〖100mg/(kg·d)for 4wk\〗, then changes in retinal tissue structure were observed and fluctuations in oxidative stress index(SOD, GSH-Px, GST)were determined.<p>RESULTS: The results of <i>in vitro</i> experiments showed that the cell activity was significantly decreased after irradiation, the LDH activity and TBARS content were increased, and the activity of antioxidant enzyme system were decreased. However, Dp treatment could increase cell viability, decrease LDH activity and TBARS content, and increase the activity of antioxidant enzyme system. <i>In vivo</i> experiments showed that Dp can protect the structural integrity of retina, reduce the content of TBARS in retinal tissue, and increase the activity of SOD, GSH-Px and GST.<p>CONCLUSION: Dp may protect retinal against Photochemical factors -induced oxidative damage by regulating the oxidation-antioxidant system.

Proteomic research of biomarker of colorectal cancer metastasis / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To explore the potential markers of colorectal cancer metastasis and the influence of 5-FU on differentially expressed proteins by using proteomic technology, and to elucidate the mechanism of colorectal cancer metastasis.</p><p><b>METHODS</b>Human colorectal carcinoma cell lines of different metastatic potential, Lovo and SW480 were conventionally cultured, and the protein was extracted. 50% inhibitory concentration (IC(50)) of 5-FU to these two cell lines was measured by MTT assay. Proteins of these two cell lines after intervention by 5-FU at IC(50) were extracted, then 2-dimensional gel electrophoresis was conducted for the proteins. The differential protein spots were examined by mass spectrometry and analyzed by bioinformatics. Difference of expressed proteins in two cell lines before and after the intervention of 5-FU was validated by Western blot and immunofluorescence.</p><p><b>RESULTS</b>Eleven differentially expressed proteins were identified by 2-dimensional gel electrophoresis and mass spectrometry. The hnRNP K protein and PDI were selected to be examined by Western blot and immunofluorescence. Results revealed that the expression of hnRNP K in Lovo was higher than that in SW480, while the expression of PDI was lower in Lovo. After intervention by 5-FU at IC(50), the expression of hnRNP K in Lovo decreased more as compared to SW480, while the expression of PDI in SW480 increased more as compared to Lovo.</p><p><b>CONCLUSION</b>There are significant differences in expression of hnRNP K and PDI proteins between Lovo and SW480 cell lines, and the proteins alter regularly after 5-FU intervention.</p>

Study on specific metabonomic profiling of serum from colorectal cancer patients by gas chromatography-mass spectrometry / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To study the specific metabonomic profiling of serum from colorectal cancer patients to find out the low molecule metabolites associated intimately with colorectal cancer,and to establish specific metabolic model for the diagnosis of colorectal cancer.</p><p><b>METHODS</b>The metabonomic profiles of the serum samples from colorectal cancer(CRC) patients(n =31) and healthy adults(n =8) were investigated by gas chromatography-mass spectrometry (GC-MS) technique combined with a commercial mass spectral library for the peak clustering based on metabolites.</p><p><b>RESULTS</b>Thirty-four endogenous metabolites including some amino acids, carbohydrates, fatty acids and other intermediate metabolites were identified. By t test statistics with P<0.05, P<0.01 respectively, L-valine, L-threonine, 1-deoxyglucose, glycine and ribitol levels were decreased significantly, but 3-hydroxybutyric acid level was increased significantly in the CRC patient group as compared with healthy adult group. PLS-DA based on these metabolites discriminated two groups for each other. Hierarchical clustering based on above 6 significant differential metabolites revealed that the prediction accuracy of colorectal cancer group was 93.5%.</p><p><b>CONCLUSION</b>GC-MS technique is an alternative tool for the metabonomic study and would be certainly beneficial to the pathological research, early diagnosis and therapy evaluation of CRC.</p>

Comparative proteomic study at the different stages during initiation and evolution of experimental colorectal carcinoma / 肿瘤

Objective: To research the proteins differentially expressed during evolution of experimental colorectal carcinoma (normal mucosa→adenoma→carcinoma→liver metastasis) so as to find the early diagnostic biomarker of colorectal cancer as well as to understand its pathogenesis mechanism. Methods: Ninety male rats were injected with 1, 2-dimethylhydrazine intraperitoneally and sacrificed at different weeks to establish the experimental colorectal tumor models (from normal mucosa to liver metastasis). These samples at different stages were collected and divided into four groups (normal mucosa group, adenoma group, carcinoma group, and liver metastasis group). The proteins of these 4 groups were extracted to conduct 2-dimensional gel electrophoresis. The differential protein spots were examined by mass spectrometry and analyzed by bioinformatics. Results: Ten differentially expressed proteins were identified by 2-dimensional gel electrophoresis and mass spectrometry including α-enolase, cardiac α-actin (CA), transgelin protein, myosin regulatory light chain smooth muscle isoform (MRLC), glyceraldehydes-3-phosphate dehydrogenase (GAPDH), haptoglobin, disulfideisomerase (DI), creatine kinase mitochondrial (CKm), heat shock protein-8 (HSP-8) and Keratin complex-2 (KC-2). Conclusions: There exist differentially expressed proteins at various stages during the evolution of colorectal carcinoma. These proteins may be the candidate biomarkers for the early diagnosis of colorectal carcinoma. Proteomic technology is an effective way for preliminary identification of the tumor biomarkers.