Expression and regulation of metalloproteinases-2,-9 and tissue inhibitors of metallo-proteinases in rat corpus luteum

The expression and regulation of metallopro-teinases-2, -9 (MMP-2, -9) and their tissue inhibitors TIMP-1, -2, -3 mRNA were studied in this experiment. In the PMSG-hCG primed pseudopregnant rat, MMP-2, -9 mRNA levels were the highest at Day 1, decreased from Day 4, and reached the minimal level at Day 8, then increased at Day 14; no significant changes were observed in TIMP-2 mRNA expression from Day 1 to Day 14; TIMP-3 mRNA expression was the lowest at Day 1, increased from Day 4, reached the maximal level at Day 8, and persisted to Day 14. TNF-α could significantly increase the expression of MMP-2, -9 and TIMP-1 mRNA in the in vitro perfused pseudopregnant CL, and decrease the expression of TIMP-3 mRNA, but had no effect on TIMP-2 mRNA expression. The results indicate that MMP-2, -9 and TIMP-1, -2, -3 might be involved in the regulation of CL function and maintenance of CL structure via their coordinated gene expression. TNF-a could inhibit luteal regression via increasing MMP-2, -9 and TIMP-1 mRNA

Expression of gelatinases and tissue inhibitors of metallo-proteinases in the rhesus monkey(Macaca mulatta) corpus luteum

Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) are believed to play important roles in the formation and regression of corpus luteum (CL). This study is to investigate the expression of gelatinases (MMP-2, -9) and TIMPs in the rhesus monkey CL in both early and late luteal phases and during the early stages of pregnancy. Ovaries were collected from regularly cycling rhesus monkey at D5 and D15 following ovulation and at D12, D18 and D26 of pregnancy. In situ hybridization revealed that in the CL MMP-2 niRNA was expressed during both formation and regression, while MMP-9 mRNA was mainly localized in the late luteal phase. Reduction of MMP-2, -9 transcripts in the CL was observed during pregnancy. MMP-2 mRNA in the CL reduced to an undetectable level at D26 of pregnancy. TIMP-1 mRNA was highly expressed in the CL in both early and late luteal phases and persisted throughout the early stages of pregnancy. Strong signal for TIMP-2 mRNA was also detected in both luteal phases, and the

Effects of Tribulus terrestris saponins on proliferation and invasion of A549 cells

Objective:Tribulus terrestris saponin is a traditional Chinese medicine in China.This experiment was designed to investigate the effects of tribulus terrestris saponin on the proliferation and invasion ability of non-small cell lung cancer A549 cells.Methods:A549 cells were divided into normal control and experimental groups(Tribulus terrestris saponin 250μg/mL group,Tribulus terrestris saponin 200μg/mL group,Tribulus terrestris saponin 150μg/mL group,Tribulus terrestris saponin 100μg/mL group,Tribulus terrestris saponin 50μg/mL group).The proliferation viability of the cells in each group was detected by CCK8,the invasion of tumor cells was detected by Transwell model.The mRNA expression of MMP9 and caspase-3 in each group of cells was detected by RT-PCR.Immunofluorescence staining was used to observe the fluorescence intensity of caspase-3 in each group of cells.Results:Compared with the normal control group,tribulus terrestris saponin significantly inhibited the proliferation activity and invasion ability of A549 cells,which was statistically significant(P<0.01).In the invasion assay,compared with the control group,MMP9 expression was significantly reduced and caspase-3 expression was significantly increased in the tribulus terrestris saponin group,and both were concentration-dependent,with statistically significant differences(P<0.01).By cellular immunofluorescence staining experiments,it was found that the fluorescence expression of caspase-3 was enhanced in the experimental group compared with the normal control group,in which the high concentration saponin group was significantly higher than the low concentration group.Conclusion:Tribulus terrestris saponin can inhibit the invasive ability of A549 cells by down-regulating the expression of MMP9,and induce irreversible apoptosis by up-regulating the activation of caspase-3 expression to form caspase-3.

Specific shRNA targeting of FAK influenced collagen metabolism in rat hepatic stellate cells

AIM:To investigate the effects and mechanism of disruption of focal adhesion kinase(FAK) expression on collagen metabolism in rat hepatic stellate cells(HSC).METHODS:The plasmids expressing FAK short hairpin RNA(shRNA) were transfected into HSC-T6 cells,and the level of FAK expression was determined by both real-time quantitative polymerase chain reaction(QPCR) and Western blotting analysis.The production of type collagen and type collagen in FAK-disrupted cells was analyzed by real-time Q-PCR.The level of collagen metabolism proteins,including matrix metalloproteinases-13(MMP-13) and tissue inhibitors of metalloproteinases-1(TIMP-1) was also determined by both real-time Q-PCR and Western blotting analysis.RESULTS:The transfection of FAK shRNA plasmids into HSC resulted in disrupted FAK expression.Compared with the HK group,the levels of type collagen and type collagen mRNA transcripts in FAK shRNA plas-mid group were signif icantly decreased(0.69 ± 0.03 vs 1.96 ± 0.15,P = 0.000;0.59 ± 0.07 vs 1.62 ± 0.12,P = 0.020).The production of TIMP-1 in this cell type was also signif icantly reduced at both mRNA and protein levels(0.49 ± 0.02 vs 1.72 ± 0.10,P = 0.005;0.76 ± 0.08 vs 2.31 ± 0.24,P = 0.000).However,the expression of MMP-13 mRNA could be significantly up-regulated by the transfection of FAK shRNA plasmids into HSC(1.74 ± 0.20 vs 1.09 ± 0.09,P = 0.000).CONCLUSION:These data support the hypothesis that shRNA-mediated disruption of FAK expression could attenuate extracellular matrix(ECM) synthesis and promote ECM degradation,making FAK a potential target for novel anti-f ibrosis therapies.

Techniques for colorectal anastomosis

Colorectal anastomotic leak remains one of the most feared post-operative complications, particularly after anterior resection of the rectum with, the shift from abdomino-peritoneal resections to total mesorectal excision and primary anastomosis. The literature fails to demonstrate superiority of stapled over hand-sewn techniques in colorectal anastomosis, regardless of the level of anastomosis, although a high stricture rate was noted in the former technique. Thus, improvements in safety aspects of anastomosis and alternatives to handsewn and stapled techniques are being sought. Here, we review alternative anastomotic techniques used to fashion bowel anastomosis. Compression anastomosis using compression anastomotic clips, endoluminal compression anastomotic rings, AKA-2, biofragmental anastomotic rings, or Magnamosis all involve the concept of creating a sutureless end-to-end anastomosis by compressing two bowel ends together, leading to a simultaneous necrosis and healing process that joins the two lumens. Staple line reinforcement is a new approach that reduce the drawbacks of staplers used in colorectal practice, i.e. leakage, bleeding, misfi ring, and inadequate tissue approximation. Various nonabsorbable, semi or fully absorbable materials are now available. Two other techniques can provide alternative anastomotic support to the suture line: a colorectal drain and a polyester stent, which can be utilized in ultra-low rectal excision and can negate the formation of a defunctioning stoma. Doxycycline coated sutures have been used to overcome the post-operative weakness in anastomosis secondary to rapid matrix degradation mediated by matrix metalloproteinase. Another novel technique, the electric welding system, showed promising results in construction of a safe, neat, smooth sutureless bowel anastomosis. Various anastomotic techniques have been shown to be comparable to the standard techniques of suturing and stapling. However, most of these alternatives need to be accepted and optimized for future use.