Objective To observe effect of arginine on wound healing of diabetic rats.Meth- ods Forty male Lewis rats were equally and randomly divided into diabetic group and normal control group.The diabetic group were rendered with diabetic by using intraperitoneal(IP)streptozotocin seven days prior to surgery and underwent a dorsal skin incision with implantation of polyvinyl-alcohol sponges. Either of two groups were subdivided into arginine treatment group and saline treatment group,10 rats in each group,of which the arginine treatment group received arginine at 1 g/kg per day by IP injection, while the saline treatment group received saline injection only.Animals were sacrificed 10 days post wound to observe antibreakage tension,hydroxyproline content and mRNA expression of procollagenⅠandⅢ.Results Diabetic wounds had greatly decreased breaking strengths compared with controls. Arginine significantly enhanced wound breaking strengths,increased wound hydroxyproline levels and ele- vated mRNA for procollagenⅠandⅢin both diabetic and control animals as compared to their saline-trea- ted counterparts.Conclusion Arginine can effectively promote healing of diabetic wounds in rats.

OBJECTIVETo investigate the expression of R-spondin1 (RSpo1) in the intestinal epithelium of mice with intestinal ischemia-reperfusion injury and explore its significance.

METHODSFifty normal male Kunming mice were randomized into sham-operated group (n=10) and intestinal ischemia-reperfusion injury group (n=40), and in the latter group, the mice were subjected to 20-min intestinal mesenteric artery occlusion followed by reperfusion for 6, 12, 24, or 48 h. Enzyme-linked immunosorbent assay (ELISA) and RT-PCR were used to detect intestinal RSpo1 expression of the mice.

RESULTSThe results of RT-PCR and ELISA showed that RSpo1 expression was significantly decreased in mice at 6 h of reperfusion following the intestinal ischemia (P<0.05), and increased gradually with prolonged repersuion time, reaching the peak level at 24 h (P<0.05). The expression underwent rapid decrease afterwards to a significantly lower level than that in the control group at 48 h (P<0.05).

CONCLUSIONIntestinal ischemia-reperfusion injury may inhibit expression of RSpo1 in the early stage, and enhance its expression in the middle stage. RSpo1 can promote proliferation and differentiation of intestinal epithelial stem cells and plays an important role in the repair intestinal mucosal damage.

Animals ; Cell Proliferation ; Intestinal Mucosa ; cytology ; metabolism ; Intestines ; blood supply ; metabolism ; Male ; Mice ; Random Allocation ; Reperfusion Injury ; metabolism ; Stem Cells ; cytology ; Thrombospondins ; genetics ; metabolism

OBJECTIVETo investigate the regulatory effect of microRNA-221 (MIR221) on CDKN1C/p57 expression in colon carcinoma cells in vitro.

METHODSCaco2 cells were treated with or without anti-p57-siRNA prior to the addition of pre-MIR221 or anti-MIR221. The MIR221 expression pattern was detected by real-time RT-PCR, and the mRNA and protein levels of CDKN1C/p57 expression were detected using semi-quantitative RT-PCR and Western blotting. Caco2 cell proliferation following the treatment was detected with MTT assay. CDKN1C/p57 3'-UTR fragment was amplified by PCR from the genome DNA of human colon and inserted into a luciferase reporter plasmid. The luciferase reporter plasmid construct was then transfected into Caco2 cells along with pre-MIR221 or anti-MIR221, and the luciferase activity in the transfected cells was detected.

RESULTSMIR221-specific inhibitor significantly up-regulated CDKN1C/p57 protein expression in Caco2 cells (P<0.01). Anti-MIR221 could markedly inhibit Caco2 cell proliferation, and the inhibitory effect was obviously abolished by pretreatment with anti-p57-siRNA, suggesting that the inhibition was mediated by CDKN1C/p57 (P<0.01). A significant increase of luciferase activity was detected in Caco2 cells co-transfected with the luciferase reporter plasmid construct and anti-MIR221 (P<0.01).

CONCLUSIONSMIR221 can interact with the target site on the 3'-UTR of CDKN1C/p57 mRNA to inhibit CDKN1C/p57 expression by post-transcriptional gene silencing to promote colon carcinoma cell proliferation, suggesting the value of MIR221 as a potential target for treatment of colon carcinoma.

3' Untranslated Regions ; Caco-2 Cells ; Cell Proliferation ; drug effects ; Cyclin-Dependent Kinase Inhibitor p57 ; genetics ; metabolism ; Down-Regulation ; Humans ; MicroRNAs ; pharmacology ; RNA, Messenger ; genetics ; metabolism

OBJECTIVETo observe the pathological changes of the intestinal mucosa in rats with severe abdominal infection.

METHODA total of 60 SD rats were divided randomly into control group and experimental group (n=30), and in the latter group, the rats underwent cecal ligation and puncture (CLP) while those in the former had only laparotomy. The jejunum and ileum were sampled on postoperative days 1, 2 and 4 for optical and electron microscopic observations. The positivity rate of blood bacterial culture and plasma level of endotoxin were determined in the rats.

RESULTSNo abnormal changes were observed with either optical and electron microscope in the small intestinal mucous membrane of rats in the control group, but in rats of the experimental group, microscopic examination revealed interstitial edema, vascular engorgement and neutrophil infiltration in the small intestine mucous membrane and the submucosa, and electron microscopy demonstrated loose and disorderly arrangement of the microvilli of the intestinal epithelium. Plasma endotoxin level in rats in the experimental group was 5- to 12-fold higher than that in the control group. The positivity rates of blood bacterial culture were 20%, 30% and 10% on postoperative days 1, 2 and 4 respectively in the experimental group, but were all zero in the control group.

CONCLUSIONPathologic lesions in the intestinal mucosa occur during the early stage of severe abdominal infection in rats as the result of bacteria and endotoxin translocation.

Animals ; Bacteria ; isolation & purification ; Bacterial Infections ; blood ; microbiology ; pathology ; Bacterial Translocation ; Cecum ; Endotoxins ; blood ; Female ; Intestinal Diseases ; etiology ; microbiology ; pathology ; Intestinal Mucosa ; microbiology ; pathology ; ultrastructure ; Intestine, Small ; microbiology ; pathology ; Ligation ; adverse effects ; Male ; Microscopy, Electron ; Punctures ; adverse effects ; Random Allocation ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the effect of FOLFOX4 neoadjuvant chemotherapy on the non-tumoral liver in patients with metastatic colorectal carcinoma.

METHODSA large series of surgically resected liver metastases(n=42) was selected and the morphological changes were examined by light and electron microscope. The mRNA and protein levels of connective tissue growth factor (CTGF) expression were detected by semi-quantitative RT-PCR and Western blotting analysis.

RESULTSTwelve (63.2%) of the 19 post-chemotherapy liver resection specimens had sinusoidal dilatation and hemorrhage. In contrast, 23 livers treated by surgery alone remained normal. Neoadjuvant chemotherapy could significantly enhance the mRNA and protein levels of CTGF expression in hepatic stellate cells.

CONCLUSIONSystemic FOLFOX4 neoadjuvant chemotherapy in metastatic colorectal carcinoma frequently causes morphological injuries involving hepatic microvasculature and induces CTGF expression in hepatic stellate cells to participate in hepatic fibrosis.

Adult ; Aged ; Aged, 80 and over ; Colorectal Neoplasms ; pathology ; Female ; Humans ; Liver ; pathology ; Liver Neoplasms ; drug therapy ; pathology ; secondary ; Male ; Middle Aged ; Neoadjuvant Therapy

OBJECTIVETo explore the effect of L-arginine (L-Arg) on intestinal mucosal cell apoptosis in rats with severe abdominal infection.

METHODSEighteen Wistar rats were randomized into 3 groups, namely the CLP group (n=6) in which the rats were subjected to cecal ligation plus puncture (CLP) to induce severe abdominal infection, L-Arg group (n=6) where the rats received 300 mg/kg peritoneal L-Arg injection following CLP establishment, and the control group (n=6) where the rats underwent ventrotomy only. Intestinal epithelial apoptotic cells were quantified in each group using TUNEL assay 24 h after the operation.

RESULTSCompared with the control group, the rats in CLP and L-Arg groups showed significantly increased number of apoptotic cells in the intestinal epithelium 24 h after the operation (P<0.001). The apoptotic index (AI) in the L-Arg group (18.1-/+2.2) was significantly lower than that in CLP group (20.8-/+2.3, P=0.038).

CONCLUSIONSevere abdominal infection results in increased apoptosis of the intestinal epithelial cells in rats, and L-Arg treatment may reduce the cell apoptosis.

Abdominal Cavity ; Animals ; Apoptosis ; drug effects ; Arginine ; pharmacology ; Cecum ; injuries ; Disease Models, Animal ; Epithelial Cells ; drug effects ; Infection ; drug therapy ; pathology ; Intestinal Mucosa ; cytology ; drug effects ; Rats ; Rats, Wistar

OBJECTIVETo investigate the effects of atorvastatin on expressions of scavenger receptor A and secretion of monocyte chemoattractant protein-1 (MCP-1) in foam cells.

METHODSTHP-1 cells were induced to differentiate into macrophages by PMA and treated with 0.1% BSA (control), ox-LDL (100 mg/L) or ox-LDL plus atorvastatin (5, 10, 20 micromol/L) for 24 hours. MCP-1 concentration in cell substratum was measured by ELISA. Scavenger receptor A expression was observed under fluorescent microscope after incubated with DiI-Ac-LDL. The relationship between concentration of MCP-1 and the activity of scavenger receptor A was also analyzed.

RESULTSCompared to the control cells, MCP-1 concentration in ox-LDL treated cells was significantly increased after 6 hours, peaked at 12 hours and was still significantly increased after 24 hours (all P < 0.05 vs. baseline). The activity of scavenger receptor A was also significantly increased in ox-LDL treated cells (P < 0.01 vs. control). The activity of scavenger receptor A proteins correlated positively to the concentration of MCP-1 in ox-LDL treated cells (r = 0.683, P < 0.01). Atorvastatin significantly attenuated these changes in a dose-dependent manner.

CONCLUSIONSScavenger receptor A and MCP-1 expressions were significantly increased in the course of monocyte lines THP-1 differentiating into macrophages and foam cells. The anti-atherosclerosis effect of atorvastatin might be partly achieved by inhibiting the secretion of MCP-1 and expression of scavenger receptor A in foam cells.

Atorvastatin Calcium ; Cell Differentiation ; Cell Line ; Chemokine CCL2 ; metabolism ; Foam Cells ; cytology ; drug effects ; metabolism ; Heptanoic Acids ; pharmacology ; Humans ; Monocytes ; cytology ; drug effects ; metabolism ; Pyrroles ; pharmacology ; Scavenger Receptors, Class A ; metabolism

OBJECTIVETo investigate miRNA-221 expression in human colorectal carcinoma (CRC) cells and the effects of miR-221-specific inhibitor on the proliferation and apoptosis of CRC cells.

METHODSFour human CRC cell lines (HT-29, Lovo, SW-480, and CaCO2) were examined for miRNA-221 expression using real-time Q-PCR. The specific 2,-methoxy-modified RNA oligonucleotides of miR-221 (anti-miR-221) were synthesized and transfected into Caco2 cells via liposome, and the changes in the expression of miR-221 in the cells were detected by real-time Q-PCR. The proliferation and apoptosis of the transfected CRC cells were detected using MTT assay and flow cytometry.

RESULTSThe 4 human CRC cells showed significantly upregulated expression of miR-221 compare with HUVECs (P<0.01). The miR-221-specific inhibitor, anti-miR-221, significantly inhibited the expression of miR-221 in Caco2 cells and suppressed the cell proliferation, causing also obvious cell apoptosis (P<0.01).

CONCLUSIONThe miR-221-specific inhibitor shows potent inhibitory effect on the growth of CRC cells, suggesting its value as a potential anti-tumor candidate for treatment of CRC.

Apoptosis ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Colorectal Neoplasms ; pathology ; Humans ; MicroRNAs ; antagonists & inhibitors ; metabolism

OBJECTIVETo observe the effect of L-arginine on diabetic rats.

METHODSForty adult male Lewis rats were randomized equally into diabetic and normal control groups, and the former rats were treated intraperitoneally with streptozotocin to induce diabetes mellitus. Seven days later, half of the diabetic and normal rats were injected intraperitoneally with L-arginine at the daily dose of 1 g/kg, while the remainder were given saline instead. All the rats were euthanized on 10 days after L-arginine or saline treatment, and their body weight, plasma protein, arginine and sugar, food and water intake were analyzed.

RESULTSDiabetic rats had obviously decreased body weight, plasma protein and arginine but increased blood sugar and food and water intakes in comparison with the control rats. L-arginine significantly increased plasma protein and arginine, decreased food and water intakes, but failed to prevent weight loss and blood sugar increment in diabetic rats as compared to their saline-treated counterparts. L-arginine supplementation did not result in any changes other than arginine elevation in the control rats.

CONCLUSIONL-arginine supplementation can partially improve polydipsia and polyphagia and increase plasma protein in diabetic rats.

Animals ; Arginine ; administration & dosage ; blood ; therapeutic use ; Blood Glucose ; metabolism ; Blood Proteins ; metabolism ; Body Weight ; drug effects ; Diabetes Mellitus, Experimental ; blood ; drug therapy ; physiopathology ; Drinking ; drug effects ; Eating ; drug effects ; Injections, Intraperitoneal ; Male ; Rats ; Rats, Inbred Lew

OBJECTIVETo investigate the expression of microRNA-221 (miR-221) and CDKN1C/P57 in colorectal carcinoma (CRC) and adjacent non-cancerous tissues. The effect of miR-221-specific inhibitor on cell proliferation and apoptosis in CRC cells was also assessed.

METHODSThe expression of miR-221 was detected by real-time RT-PCR. CDKN1C/P57 mRNA and corresponding protein expression pattern were detected by semi-quantitative RT-PCR and Western-blot. The specific 2'-methoxy-modified RNA oligonucleotide of miR-221(miRNA inhibitor,anti-miR-221) was designed, synthesized and transfected into Caco2 cell by liposome. Finally, the status of CRC cell proliferation and apoptosis were detected by MTT assay and flow cytometry.

RESULTSThe expression of miR-221 was significantly up-regulated in CRC tissues as compared to the adjacent non-cancerous tissues(2.041±1.401 vs. 0.806±0.341, P<0.01). There was no significant difference in CDKN1C/P57 mRNA expression between CRC and non-cancerous tissues, whereas CDKN1C/P57 protein markedly decreased in CRC (3.019±1.708 vs. 0.972±0.316, P<0.01). miR-221-specific inhibitor significantly enhanced CDKN1C/P57 protein expression, inhibited proliferation of CRC cells and induced apoptosis of CRC cells(P<0.01).

CONCLUSIONSmiR-221 inhibits CDKN1C/P57 expression by post-transcriptional gene silencing to promote CRC development and progression. miR-221-specific inhibitor potentially inhibits the growth of CRC cells. Therefore, it may be a new target for the biologic therapy for CRC.

Adult ; Aged ; Apoptosis ; genetics ; Caco-2 Cells ; Cell Line, Tumor ; Cell Proliferation ; Colorectal Neoplasms ; genetics ; metabolism ; pathology ; Cyclin-Dependent Kinase Inhibitor p57 ; genetics ; metabolism ; Female ; Humans ; Male ; MicroRNAs ; genetics ; Middle Aged ; RNA Interference