Repeatability of the "flash-replenishment" method in contrast-enhanced ultrasound for the quantitative assessment of hepatic microvascular perfusion

This study aimed to evaluate the feasibility and repeatability of the flash-replenishment method in contrast-enhanced ultrasound (CEUS) perfusion imaging and assess quantitatively microvascular perfusion in the liver. Twenty healthy New Zealand rabbits were submitted to CEUS perfusion imaging with continuous intravenous infusion. Using flash-replenishment kinetics, the dynamic process of depletion and refilling of microbubble contrast agent was recorded. The hepatic microvascular perfusion parameters were calculated, including region of interest, peak intensity (PI), area under the curve (AUC), and hepatic artery to vein transit time (HA-HVTT). A consistency test was performed for multiple measurements by the same operator and blind measurements by two different operators. The hepatic perfusion imaging of 3×108 bubbles/min had minimal error and the best imaging effect and repeatability. The variability of the perfusion parameter measured at 3 cm depth under the liver capsule was at a minimum with coefficient of variation of 3.9%. The interclass correlation coefficient (ICC) of measurements taken by the same operator was 0.985, (95% confidence interval, CI=0.927-0.998). Measurements taken by two operators had good consistency and reliability, with the ICC of 0.948 (95%CI=0.853-0.982). The PI and AUC of liver parenchyma after reperfusion were lower than before blocking; and HA-HVTT was significantly longer than before blocking (P<0.05). The flash-replenishment method in CEUS perfusion imaging showed good stability and repeatability, which provide a valuable experimental basis for the quantitative assessment of hepatic microvascular perfusion in clinical practice.

Saikosaponins-b suppresses tumor growth and angiogenesis of hepatocellular carcinoma by regulating VEGF/ERK/HIF-1α signal pathway / 中国药理学与毒理学杂志

OBJECTIVE Angiogenesis therapy has attracted interest as a potential treatment for hepatocellular carcinoma (HCC). In this study, we investigated the anti-proliferative activities and anti-angiogenesis effects of saikosaponins (SS)-b on hepatocellular carcinoma (HCC) and its regulation on VEGF/ERK/HIF-1α signal pathway. METHODS H22 hepatoma-bearing mice model and HepG-2 cells were used to study the anti-tumor and anti-angiogenesis effects of SS-b in vivo and in vitro. Pathological change of tumor tissue was observed by HE staining, the microvascular changes were detected by immunohistochemical method. The effects of SS-b on angiogenesis were examined by using the chick embryo chorioallantoic membrane (CAM) model. The effects of SS- b on proliferation, migration and invasion were investigated by MTT assay, scratch wound healing assay and transwell assay inhuman umbilical vein endothelial cell (HUVEC) and HepG2 cells in vitro. Vascular endothelial growth factor (VEGF), matrix metalloproteinase-2/9(MMP-2/9), hypoxia-inducible factor-1α (HIF-1α) expression and the phosphorylation of extracellular regulated kinase(ERK) were analyzed using RT-PCR and Western-blot. RESULTS SS-b effectively inhibited the tumor growth of H22 mice in vivo. The inhibitory rate of tumor was 49.1%, 50.7%, 66.1% in SS-b 5, 10 and 20 mg·kg-1 group respectively. HE staining results showed that SS-b induced tumor necrosis and nuclear dissolution in H22 mice. Moreover, SS-b also reduced the number of microvessels of tumor tissue in H22 mice significantly and suppressed the angiogenesis of CAM induced by b-FGF. SS-b had an obvious inhibitory effect on cell proliferation, migration and invasion of HUVEC cells and HepG-2 cells. These effects were associated with down-regulation of the expression of MMP2/9 and suppression of VEGF/ERK/HIF-1α signaling in H22 mice and Hep-G2 cells. CONCLUSION Our findings showed that SS-b exerts anti-tumor effects by inhibit?ing tumor angiogenesis via regulating VEGF/ERK/HIF-1α signal pathway in vivo and in vitro.

Saikosaponin-b regulates the proliferation and apoptosis of HepG2 cells by targeting the MACC1/c-Met/Akt signaling pathway / 中国药理学与毒理学杂志

OBJECTIVE Metastasis-associated in colon cancer-1 (MACC1) is an oncogene that has been newly identified. It promotes tumor proliferation and invasion via the MET pathway. Our study investigated the effects of Saikosaponin-b(SS-b) on the proliferation and apoptosis of HepG2 cells and its regulation on MACC1/c-Met/Akt signaling pathway. METHODS HepG2 cells were treated with SS-b (10-800 g·L-1) for 48 h in vitro. The CCK-8 assay was used to assess cell proliferation, and cell apoptosis was determined by Hoechst33258 staining, AnnexinⅤ/PI staining and caspase 3 assay. RT-PCR was used to examine the expression of MACC1, c- MET and hepatocyte growth factor (HGF) mRNA. MACC1 protein was detected by Western blot and immunohistochemistry. The protein expressions of p-c-MET, c-MET, p-AKT, AKT, p-BAD, BAD were measured by Western blot. RESULTS SS-b inhibited the growth of HepG2 cells in dose-dependent way and induced cell apoptosis significantly. HepG2 cells showed karyopyknosis, fragmentation and fluorescence highlight in SS-b treatment group. FCM results showed that apoptosis rate of HepG2 cells increased with SS- b concentration. The immunofluores?cence results showed that the MACC1 expression decreased significantly in HepG2 cells treated with SS-b. The expression levels of MACC1, c-MET and HGF mRNA in HepG2 cells were significantly inhibited by SS-b. SS-b also significantly decreased the protein expressions of MACC1, p-c-MET and p-AKT while increased the expression of p-BAD and caspase 3 in HepG2 cells(P<0.05). CONCLUSION SS-b inhibited the proliferation and induced the apoptosis of HepG2 cells by targeting the MACC1/c-Met/Akt signaling pathway.