ABSTRACT
Objective:To investigate the effects of piperine on experimental colon carcinogenesis induced by 1, 2-dimethylhydrazine (DMH)/sodium dextran sulfate (DSS) and its mechanism.Methods:36 mice were divided into control group, model group and piperine group, 12 mice in each group. The control group was given normal saline by gavage; The model group and piperine group were given 3.6 mg/(kg·d) of normal saline and piperine respectively after establishing the experimental colon cancer model induced by DMH/DSS. Tumor load and volume were observed. Hematoxylin and eosin (HE) staining was used to observe the histological change of colon in mice. RAS/PI3K/AKT related pathway protein expression was detected by Western blot.Results:The body weight gain, protein expression levels of cleaved poly-ADP ribose polymerase (PARP), cleaved caspase-3 in model group were significantly lower than those in the control group (all P<0.05). The protein expression levels of Bcl-2, Bax, pan-Ras, p-MEK, p-ERK, PI3K, p-AKT, NF-κBP65, c-Myc and cyclin D1 in model group were significantly higher than those in the control group (all P<0.05). The body weight gain, protein expression levels of cleaved PARP and cleaved caspase-3 in piperine group were significantly higher than those in model group (all P<0.05). The protein expression levels of Bcl-2, Bax, pan-Ras, p-MEK, p-ERK, PI3K, p-AKT, NF-κBP65, c-Myc and cyclin D1 in piperine group were significantly lower than those in model group (all P<0.05). Conclusions:Piperine can inhibit the occurrence of experimental colon cancer induced by DMH/DSS, which may involve multiple components of RAS/PI3K/AKT signal axis.
ABSTRACT
Objective:To investigate the regulation effect of miR-125b in the gastric cancer cell growth mediated by apoptosis related protein (Fas)/apoptosis related protein ligand (FasL) signal.Methods:Gastric cancer SGC-7901 cells were cultured in vitro. MiR-125b inhibitor sequence, NC sequence and transfection reagent were transfected into SGC-7901 cells and divided into three groups: miR-125b inhibited group, NC group and control group. The expression of miR-125b in transfected cells was detected by real-time fluorescence quantitative polymerase chain reaction (qRT-PCR), and cell proliferation was detected by cell counting kit-8 (CCK-8) method. The colony formation was detected by plate cell clone formation assay. Cell apoptosis and cycle were detected by flow cytometry. The protein expression of Fas and FasL was detected by Western blot. The targeted regulation of Fas by miR-125b was detected by luciferase activity assay. Results:The expression level of miR-125 and the number of cell colony in miR-125b inhibited group was significantly lower than those in control group and NC group, and the inhibition rate of cell proliferation and apoptosis rate were significantly higher than that in control group and NC group (all P<0.05). The DNA content in G 1 phase in miR-125b inhibited group was significantly higher than that in control group and NC group, and the DNA content in S phase in miR-125b inhibited group was significantly lower than that in control group and NC group (all P<0.05). The expression of Fas and FasL protein in miR-125b inhibited group was significantly higher than that in control group and NC group (all P<0.05). The target site of miR-125b was found in 3′-UTR of Fas mRNA, and compared with the NC+ Fas 3′UTR-Wt group, the activity of luciferase in the miR-125b inhibited group+ Fas 3′-UTR-Wt group decreased significantly ( P<0.05). Conclusions:Inhibition of miR-125b expression can activate Fas/FasL signal and inhibit SGC-7901 cell proliferation, induce G 1 phase arrest of cell cycle and promote apoptosis.
ABSTRACT
Objective To investigate the effect of astrocytes activated by TNF? on the relapse of epilepsy. Methods The purified astrocytes of cultured rat hippocampus were stimulated by TNF?.The expression of NF\|? Bp65 was checked by immunocytochemical method and the release of glutamate(Glu) from astrocytes was measured by high performance liquid chromatography(HPLC).The astrocytes conditioned medium(ACM) stimulated by TNF? was collected and injected into lateral ventricle of chronic Coriaria Lactone kindled rats during the interictal period.The changes both in behavior and electroencephalogram(EEG) were recorded.The expression of NF\|? Bp65 and glial fibrillary acidic protein(GFAP) of hippocampus were also studied by immunocytochemical method. Results 1.TNF? could promote the release of Glu by astrocytes and quickly induce the nuclear expression of NF\|? Bp65 in cultured astrocytes.2.After lateral ventricular injection,four class epileptic behaviors were induced,which were confirmed by epileptic charge EEG.At 0^5?h after injection of ACM,NF ? Bp65 expression in hippocampal cells especially in the CAl area were induced.It reached to the maximal levels at 2\|4?h and returned to control level at 8h.At 1h after injection of ACM,the increase of the number of positive GFAP \|immunoreactivity(IR) cells of hippocampus could be observed.The expression of GFAP reached to the top level at 4h and still maintained at a higher level than the control group until 8h.Conclusion\ Astrocytes activa\|ted by TNF? could induce the relapse of epilepsy by some solube neuro\|active substance.