Effects of TCMP-1 on the changes of platelet endothelial cell adhesion molecule-1 expression in acute edematous pancreatitis

BACKGROUND: Traditional Chinese medicine is a potent agent in the management of clinical and experimental acute pancreatitis (AP), but the molecular mechanism of its the- rapeutic action is unclear. Numerous experimental and clinical studies have shown that platelet endothelial cell ad- hesion molecule-1 (PECAM-1) is pivotal to leukocyte re- cruitment, which results in microcirculatory injury during inflammation, but its role in acute pancreatitis is poorly un- derstood. We investigated the effects of a compound of tra- ditional Chinese medicine pancreatitis-1 (TCMP-1) on the changes of platelet endothelial cell adhesion molecule-1 (PECAM-1) expression on polymorphonuclear leukocytes (PMNs) in acute edematous pancreatitis (AEP). METHODS: The model of acute pancreatitis was estab- lished by subcutaneous injection of caerulein, and TCMP-1 treated groups were given TCMP-1 by catheterization from mouth to stomach (20 ml/kg) immediately after first time subcutaneous injection of caerulein. The changes of expres- sion of PECAM-1 on leukocytes from the blood of the splenic vein and inferior vena cava were determined by flow cytometry. RESULTS: In the AEP group, expression of PECAM-1 on PMNs was not significantly different between pancreatic microcirculation and systemic circulation at AEP2h and AEP4h time point. Then from AEP4h time point to AEP8h time point, expression of PECAM-1 was up-regulated in systemic circulation while it was down-regulated in pancre- atic microcirculation and was significantly different be- tween pancreatic microcirculation and systemic circulation at AEP8h time point (P<0.05). In the TCMP-1 treated group, compared with the AEP group, expression of PE-CAM-1 on PMNs decreased in different levels between pan- creatic microcirculation and systemic circulation and was of significant difference at AEP8h time point (P <0.05). CONCLUSION: Inhibition of PECAM-1 expression on PMNs may prevent PMNs from transmigration through the endo- thelium and may be one of the treatment mechanisms of TCMP-1 decoction on AEP.

Differences in platelet endothelial cell adhesion molecule-1 expression between peripheral circulation and pancreatic microcirculation in cerulein-induced acute edematous pancreatitis

AIM: To investigate the changes of platelet endothelial cell adhesion molecule-1 (PECAM-1) expression on polymorphonuclear leukocytes (PMNs) in peripheral circulation and pancreatic microcirculation in cerulein-induced acute edematous pancreatitis (AEP).METHODS: Fifty Wistar rats were randomly divided into control group (n=10) and AEP group (n=40). A model of AEP was established by subcutaneous injection of cerulein 5.5 and 7.5 μg/kg at 0 and 1 h after the beginning of experiment respectively. PECAM-1 expression on PMNs from splenic vein and inferior vena cava was determined by RT-PCR at mRNA level and determined by flow cytometry at protein level.RESULTS: In experimental rats, an increased PECAM-1mRNA expression was seen from 4 to 8 h of AEP in peripheral circulation (0.77±0.25%, 0.76±0.28%, 0.89±0.30%,1.00±0.21% ), while in pancreatic microcirculation,expression decreased from 2 h and reached the lowest level at 6 h of AEP (0.78±0.29%, 0.75±0.26%, 0.62±0.28%,0.66±0.20%). There were significant differences at 8-h time point of AEP between peripheral circulation and pancreatic microcirculation (1.00±0.21% vs0.66±0.20%, P＜0.05).Meanwhile,the difference at protein level was also found.CONCLUSION: A reverse expression of PECAM-1 on PMNs was found between peripheral circulation and pancreatic microcirculation, suggesting that inhibition of PECAM-1expression may improve the pathological change of AEP.

The relationship between platelet endothelial cell adhesion molecule-1 and paraquat-induced lung injury in rabbits

BACKGROUND:Platelet endothelial cell adhesion molecule-1(PECAM-1),also known as CD31,is mainly distributed in vascular endothelial cells.Studies have shown that PECAM-1 is a very significant indicator of angiogenesis,and has been used as an indicator for vascular endothelial cells.The present study aimed to explore the relationship between the expression of PECAM-1 and the degree of acute lung injury(ALI) and fibrosis in paraquat(PQ) induced lung injury in rabbits.METHODS:Thirty-six adult New Zealand rabbits were randomly divided into three groups(12rabbits in each group) according to PQ dosage:8 mg/kg(group A),16 mg/kg(group B),and 32 mg/kg(group C).After PQ infusion,the rabbits were monitored for 7 days and then euthanized.The lungs were removed for histological evaluation.Masson staining was used to determine the degree of lung fibrosis(LF),and semi-quantitative immune-histochemistry analysis to determine the expression of PECAM-1.Pearson's product-moment correlation analysis was performed to evaluate the relationship between the expression of PECAM-1 and the extent of lung injuries expressed by ALI score and degree of LF.RESULTS:Rabbits in the three groups showed apparent poisoning.The rabbits survived longer in group A than in groups B and C(6.47±0.99 days vs.6.09±1.04 days vs.4.77±2.04 days)(P<0.05).ALI score was lower in group A than in groups B and C(8.33±1.03 vs.9.83±1.17 vs.11.50±1.38)(P<0.05),and there was statistically significant difference between group B and group C(P=0.03).LF was slighter in group A than in groups B and C(31.09%±2.05%vs.34.37%±1.62%vs.36.54%±0.44%)(P<0.05),and there was statistically significant difference between group B and group C(P=0.026).The PEACAM-1 expression was higher in group A than in groups B and C(20.31%±0.70%vs.19.34%±0.68%vs.18.37%±0.46%)(P<0.05),and there was statistically significant difference between group B and group C(P=0.017).Pearson's correlation analysis showed that the expression of PECAM-1 was negatively correlated to both ALI score(Coe=-0.732,P=0.001)and degree of LF(Coe=-0.779,P<0.001).CONCLUSIONS:The PECAM-1 expression significantly decreases in New Zealand rabbits after PQ poisoning,and the decrease is dose-dependent.The PECAM-1 expression is negatively correlated with ALI score and LF,showing a significant role in the development of lung injuries induced by PQ.

Correlation of PECAM-1 gene C373G locus polymorphism with endothelial injury and placental pathological damage in patients with preeclampsia

Objective:To study the correlation of PECAM-1 gene C373G locus polymorphism with endothelial injury and placental pathological damage in patients with preeclampsia.Methods:Pregnant women with preeclampsia and healthy pregnant women delivering in Obstetrics Department of Yibin Second People's Hospital between May 2014 and September 2016 were selected and enrolled in PE group and control group respectively. Peripheral blood was collected to determine PECAM-1 gene C373G polymorphism as well as the contents of endothelial injury molecules sEng, PAR-1, sFlt-1 and ET-1;placenta tissue was collected to determine the contents of pathological damage molecules Gadd45 , TIMP2, Fas, Apaf-1 and caspase-3.Results:PECAM-1 gene C373G locus GC and GG genotype constituent ratio and allele G constituent ratio in peripheral blood of PE group were significantly higher than those of control group while CC genotype constituent ratio and allele C constituent ratio were significantly lower than those of control group. sFlt-1, sEng, PAR-1 and ET-1 contents in serum as well as Gadd45 , TIMP2, Fas, Apaf-1 and caspase-3 contents in placenta of PE group were significantly higher than those of control group;sFlt-1, sEng, PAR-1 and ET-1 contents in serum as well as Gadd45 , TIMP2, Fas, Apaf-1 and caspase-3 contents in placenta of PE patients with PECAM-1 gene C373G locus GC and GG genotypes were higher than those of PE patients with CC genotype.Conclusion: Increased allele G in PECAM-1 gene C373G loci is closely correlated with endothelial injury and placental pathological damage in patients with preeclampsia.

Involvement of Activation of C-Met Signaling Pathway in CD151-induced HUVECs Angiogenesis

CD151 is a member of the tetraspanin family that is implicated as a promoter of pathological or physiological angiogenesis. C-Met is expressed on a variety of cells including vascular endothelial cells（VECs） and up-regulated during angiogenesis. In this study, we investigated whether CD151 regulated migration, proliferation, tube formation and angiogenesis of human umbilical VECs（HUVECs） with activation of C-Met. Moreover, we studied whether CD151 could affect the angiogenic molecules such as nitric oxide（NO）, vascular cell adhesion molecule-1（VCAM-1） and vascular endothelial growth factor（VEGF）. The expression of CD151 was determined by Western blotting. The cell proliferation assay was performed using the cell counting kit-8（CCK-8） method and cell migration was assessed in microchemotaxis chambers by using fetal bovine serum（FBS） as the chemotactic stimulus. The angiogenic molecules were evaluated using ELISA. The NO level was detected using NO detection kit. The potential involvement of various signaling pathways was explored using relevant antibodies. We found that proliferation, migration and tube formation of HUVECs were promoted by CD151 with activation of C-Met, FAK and CDC42, while they were suppressed with CD151 knockdown by RNAi. Similarly, the levels of NO, VCAM-1 and VEGF in HUVECs were increased by CD151, but they were inhibited with CD151 knockdown by RNAi. These data suggested that CD151 could promote migration, proliferation, tube formation and angiogenesis of HUVECs, which was possibly related to the C-Met signaling pathways.

Temporal alterations in pericytes at the acute phase of ischemia/reperfusion in the mouse brain

Pericytes,as the mural cells surrounding the microvasculature,play a critical role in the regulation of microcirculation;however,how these cells respond to ischemic stroke remains unclear.To determine the temporal alterations in pericytes after ischemia/reperfusion,we used the 1-hour middle cerebral artery occlusion model,which was examined at 2,12,and 24 hours after reperfusion.Our results showed that in the reperfused regions,the cerebral blood flow decreased and the infarct volume increased with time.Furthermore,the pericytes in the infarct regions contracted and acted on the vascular endothelial cells within 24 hours after reperfusion.These effects may result in incomplete microcirculation reperfusion and a gradual worsening trend with time in the acute phase.These findings provide strong evidence for explaining the“no-reflow”phenomenon that occurs after recanalization in clinical practice.

Biocompatibility, biodegradation, and neovascularization of human single-unit platelet-rich fibrin glue： an in vivo analysis

Background The clinical applications of fibrin glue span over several surgical modalities.The aim of this study was to evaluate the biocompatibility and biodegradation of different formulations of platelet-rich fibrin glue in vivo and examine its effects on the neovascularization of wound sites.Methods Human-derived single-unit fibrin glue was prepared.Incisions were made on the backs of rats,and these were coated with homemade glues containing different concentrations of aminomethylbenzoic acid （Groups A-F） or commercial adhesives （Group G）.A sham control group was included （Group H）.The wounds were examined by histological analysis and immunohistochemistry at several time points.Results Successful wound closure was achieved in all groups by day 12.Acute inflammation occurred during the first six days,but gradually disappeared.The longest sealant duration was achieved using the lowest concentration of antifibrinolytic agent in a 1：10 volume ratio with cryoprecipitate.Expression levels of the platelet endothelial cell adhesion molecule-1 were significantly higher in Groups A and C compared to the control groups （Groups G and H） on day 3 （P ＜0.05）.Conclusions Single-unit platelet-rich fibrin glue has excellent biocompatibility and is associated with the upregulation of neovascularization.The addition of aminomethylbenzoic acid could prevent the degradation of fibrin glue.