ABSTRACT
Objective To explore the effect of Ginkgo biloba extract (EGb761) on apoptosis of K-ras mutational human colon cancer cells DLD1(DLD1/G13D)and its mechanism. Methods Human colon cancer cell lines DLD1/G13D and DLD1 with K-ras wild type(DLD1/WT)were cultured in vitro,the cell proliferation and apoptosis after 24 h of EGb761 were measured. Proteins involved in related signal pathway were detected by Western blot or ELISA. Results EGb761 reduced cell proliferation and induced cell apoptosis in a concentration-dependent manner in DLD1/WT and DLD1/G13D cells. EGb761 downregulated the expression of RIP1, impaired the phosphorylation of IκB and decreased the level of NF-κB in DLD1/WT and DLD1/G13D cells[DLD1/G13D: (24±4)%, DLD1/WT: (29±9)%(P<0.05). Conclusion EGb761 restrains the proliferation and induces the apoptosis of DLD1/WT and DLD1/G13D cells. The mechanism may be related to the degradation of RIP-1 and inhibition of activation of NF-κB signaling pathway.
ABSTRACT
Objective To explore the effect of Ginkgo biloba extract (EGb761) on apoptosis of K-ras mutational human colon cancer cells DLD1(DLD1/G13D)and its mechanism. Methods Human colon cancer cell lines DLD1/G13D and DLD1 with K-ras wild type(DLD1/WT)were cultured in vitro,the cell proliferation and apoptosis after 24 h of EGb761 were measured. Proteins involved in related signal pathway were detected by Western blot or ELISA. Results EGb761 reduced cell proliferation and induced cell apoptosis in a concentration-dependent manner in DLD1/WT and DLD1/G13D cells. EGb761 downregulated the expression of RIP1, impaired the phosphorylation of IκB and decreased the level of NF-κB in DLD1/WT and DLD1/G13D cells[DLD1/G13D: (24±4)%, DLD1/WT: (29±9)%(P<0.05). Conclusion EGb761 restrains the proliferation and induces the apoptosis of DLD1/WT and DLD1/G13D cells. The mechanism may be related to the degradation of RIP-1 and inhibition of activation of NF-κB signaling pathway.
ABSTRACT
It was reported that pancreatic arteries constricted during the early phase of bile salt-induced acute pancreatitis (AP), leading to pancreatic microcirculatory disturbance. We conducted this experiment to verify whether the above-mentioned finding was true. AP was induced with intraductal injection of taurodeoxyholate. Small pancreatic artery pressure in dogs was recorded. Functional capillaries were counted and calibrated by multiplying wet weight of pancreas. Pancreatic perfusion was measured with Laser Doppler flowmeter. Pancreatic arterioles of rats dilated during the initial 20 min of AP, and pancreatic arterial pressure declined during the early phase of AP in dogs (from 104.5 +/- 4.8 mmHg to 54.6 +/- 5.6 mmHg). The hematocrit of blood from inferior vena cava was significantly lower than that of portal vein at 5 min after pancreatitis induction. The "true" pancreatic functional capillary density increased. The early pancreatic microcirculatory disturbance coincided with a marked increase of portal vein pressure (PVP) as high as 9.18 +/- 0.78 mmHg. Reduction of PVP to baseline level was followed by a marked increase of pancreatic perfusion (by 1.4-fold). Arterial dilatation, but not constriction, occurred during the early phase of bile salt-induced AP. The pancreatic microcirculatory disturbance was due to a marked rise in PVP that greatly reduced the pressure difference in the pancreatic blood vessels and increased plasma extravasation which led. to local hemoconcentration.