ObjectiveTo interpret the mechanisms of vascular repair disorders in steroid-induced avascular necrosis of the femoral head (SANFH) via detection of the changes of proliferation, migration, and macrophage migration inhibitory factor (MIF)/vascular endothelial growth factor (VEGF) expressions of endothelial cells (ECs) under hypoxia/glucocorticoid. MethodsAccording to culture conditions, human umbilical vein ECs (HUVECs) at passage 3 were divided into group A (normal), group B (1.0×10-6 mol/L dexamethasone), group C (hypoxia), and group D (hypoxia+1.0×10-6 mol/L dexamethasone). The cell activity was detected by AlamarBlue; the number of viable cells was detected in live/dead cell staining; the cell morphology was observed after cytoskeleton staining; cell migration ability was compared by scratch test; and the levels of MIF and VEGF expressions were detected by ELISA. ResultsAt 24 hours after culture, the cell activity and the number of living cells in group C were significantly higher than those in the other 3 groups, showing significant difference between groups (P < 0.05), and group D had the worst cell activity and least living cells. Cytoskeleton staining showed that cells had normal morphology in groups A and B; cells had rich cytoskeleton and secretion granules in group C; cytoskeleton form disorder and nucleus pyknosis were observed in group D. Scratch test showed that the cell migration ability of group C was strongest while cell migration ability of group D was weakest. Accumulated concentration of MIF and VEGF in 4 groups significantly increased with time extending. Accumulated concentration of MIF in group C were significantly higher than that in other 3 groups at each time point (P < 0.05). Within 24 hours after intervention, stage concentration of MIF during 1-8 hours was significantly lower than that during 0-1 hour and 8-24 hours in every group (P < 0.05). Stage concentration of MIF in group C was significantly higher than other groups during 0-1 hour and 8-24 hours (P < 0.05). Within 2 hours after intervention, stage concentration of MIF in 4 groups during 0.5-1 hour was significantly higher than that during other stages (P < 0.05). Accumulated concentration of VEGF in group C was significantly higher than that in other groups at 8 and 24 hours (P < 0.05). The stage concentration of VEGF in groups C and D during 8-24 hours was significantly higher than that during 0-1 hour and 1-8 hours (P < 0.05). There was no significant difference in the stage concentration of VEGF within and among group A, B, C, and D at every stage within 2 hours after intervention (P > 0.05). ConclusionIn hypoxia environment, the proliferation and migration of ECs is enhanced, and the secretion of VEGF and MIF is increased. High concentration of dexamethasone will suppress the process above, which induces vascular repair disorders and aggravating SANFH.
Objective To investigate the effect of Wnt/β-catenin signal pathway on the apoptosis in steroid-induced avascular necrosis of femoral head (SANFH) in rats. Methods Seventy-two male Sprague Dawley rats (weighing, 200-230 g) were randomly divided into the control group (group A, n=24), the model group (group B, n=24), and the intervening group (group C, n=24). The rats in groups B and C were injected with lipopolysaccharide and methylprednisolone (MPS) to establish the SANFH model. The rats in group C were injected intramuscularly with human recombinant secreted frizzled related protein 1 (SFRP1) [1 μg/(kg·d)] at the first time of MPS administration for 30 days. The rats in group A received saline injection at the same injection time of group B. The general condition of rats in groups B and C was observed during modeling and after modeling. At 2, 4, and 8 weeks after last injection of MPS, 8 rats were sacrificed to harvest the femoral head. Histological staining was performed to evaluate osteonecrosis. Apoptosis was detected via TUNEL staining. The expressions of Wnt/β-cate nin pathway signaling molecules (activated β-catenin and c-Myc) were detected by immunohistochemistry and Western blot. Results Six rats were added in groups B and C because of 6 deaths. The other rats survived to the end of experiment. Normal bone structure was observed in group A; osteonecrosis of bone structure disturbance and disruption of the trabecula were found with time in groups B and C. Group C had the highest empty lacuna rate and apoptosis rate, followed by groups B and A, showing significant difference between groups (P < 0.05). The expression levels of activated β-catenin and c-Myc were significantly lower in group C than groups A and B (P < 0.05), and in group B than group A (P < 0.05). Conclusion Wnt/β-catenin signal pathway is involved in the pathogenesis in early SANFH model and its possible mechanism is to affect the cell cycle and cell apoptosis by the regulation of c-Myc expression.
ObjectiveTo systematically evaluate the outcomes of drug-eluting balloon (DEB) in treating coronary artery in-stent restenosis (ISR) by using meta-analysis and trial sequential analysis (TSA). MethodsWe searched PubMed, EMbase, The Cochrane Library（Issue 4, 2016）, CNKI, CBM, VIP and WanFang Data to collect randomized controlled trials (RCTs) regarding the treatment of ISR by DEB from inception to April 2016. After two reviewers independently screened citations, extracted data and assessed the bias risk of included studies, we carried out meta-analysis and TSA analysis by using RevMan 5.3 version and TSA v0.9 respectively. ResultsA total of 10 RCTs involving 1909 patients were included. Seven-hundred and forty-seven patients were included with regard to the comparison between DEB and POBA, 1162 patients were recruited to compare DEB and drug-eluting stents (DES). The results of meta-analysis revealed that DEB was associated with decreased mortality (OR=0.36, 95%CI 0.14 to 0.93, P=0.04), compared with that of plain old balloon angioplasty (POBA). And TSA showed that cumulative Z-curve strode the conventional threshold value but not the TSA threshold value which suggested a false positive result of meta-analysis. In comparison with that of POBA, DEB had a lower incidence of target lesion revascularization (TLR) (OR=0.16, 95%CI 0.07 to 0.38, P＜0.01). And the result of TSA displayed that the cumulative Z-curve strode both the conventional and TSA threshold value which validated the result of meta-analysis. Besides, the results of meta-analysis showed that there were no significant differences in mortality (OR=0.84, 95%CI 0.41 to 1.72, P=0.63) and TLR (OR=1.55, 95%CI 0.76 to 3.16, P=0.22) between DEB and DES. However, the result of TSA revealed that the cumulative Z-curve did not strode both the conventional and TSA threshold value, and the included sample size less was than required information size which suggested that the reliability of the meta-analysis needed more studies to confirm. While the subgroup analysis of EES revealed that DEB had a higher incidence of TLR than that of DEB (OR=3.37, 95%CI 1.59 to 7.15, P＜0.01). And the result of TSA displayed that the cumulative Z-curve strode both the conventional and TSA threshold value which validated the result of meta-analysis. ConclusionCurrent evidence shows, EES is superior to DEB in decreasing the incidence of TLR in patients with ISR, while DEB is superior to POBA. However, the comparison of DEB and other strategies on reducing of mortality in patients with ISR still needed more studies to prove.