[The effects of methionine and choline on the expression levels of CaMKII and CREB mRNA and proteins in rats exposed to lead].

OBJECTIVE: To study the effects of methionine and choline on the expression levels of CaMKII and CREB mRNA and proteins in hippocampus of rats exposed to lead. METHODS: Male SD rats were divided into five groups. (1) control group, (2) group exposed to lead+2 by drinking water with 0.40 g/L lead acetate, (3) group exposed to methionine and choline (1:1, 400 mg/kg), (4) group exposed to 0.40 g/L lead acetate plus methionine and choline (1:1, 100 mg/kg), (5) group exposed to 0.40 g/L lead acetate plus methionine and choline (1:1, 400 mg/kg). In 8 weeks after exposure, all rats were killed. Then CREB mRNA and CaMK II mRNA expression levels in hippocampus were detected by real-time PCR, CREB and CaMK II protein expression levels in hippocampus were measured by western blot assay. RESULTS: The expression levels (0.743 ± 0.185 and 0.729 ± 0.199) of CaMKII mRNA and CREB mRNA in the hippocampus of lead group were significantly lower than those (0.950 ± 0.238 and 0.901 ± 0.232) of control group (P < 0.05), also the expression levels (0.271 ± 0.045 and 0.212 ± 0.058) of CREB protein and pCREB protein in the hippocampus of lead group were significantly lower than those (0.319 ± 0.058 and 0.506 ± 0.125) of control group (P < 0.05). The expression levels (1.014 ± 0.210 and 1.126 ± 0.379) of CaMKII mRNA and the expression levels (1.029 ± 0.335 and 0.932 ± 0.251) of CREB mRNA in the hippocampus of 2 groups exposed to lead acetate plus methionine and choline were significantly higher than those of lead group (P < 0.05). The expression levels (0.407 ± 0.951 and 0.563 ± 0.178) of CREB protein and pCREB protein in the hippocampus of group exposed to lead acetate plus 400 mg/kg methionine and choline were significantly higher than those of lead group (P < 0.05). CONCLUSION: Methionine and choline could decrease the inhibition effects of lead on the expression of CaMKII and CREB mRNA or CREB and pCREB proteins in the hippocampus of rats.

[Knock-down of apollon gene by antisense oligodeoxynucleotide inhibits the proliferation of Lovo cells and enhances chemo-sensitivity].

In this study, the effects of apollon antisense oligodeoxynucleotide (ASODN) on the proliferation and apoptosis of human Lovo cells in vitro were investigated. Apollon ASODN was incubated with human colorectal Lovo cells for 48 h, the proliferation inhibition and the clone forming rates were detected by WST method and clone formation assay, respectively. The expression of apollon mRNA was analyzed by real time fluorescent quantitative reverse transcription polymerase chain reaction. The percentage of apoptotic cells and cell cycle distribution were determined by flow cytometry. The morphology of apoptotic cells was examined by fluorescence microscope. Lovo cells incubated with apollon ASODN combined with 5-fluorouracil (5-FU), cisplatin (DDP) or epirubicin (EPI) of different concentrations, cell proliferation inhibition rates were detected with WST method and IC50 was calculated. It was found that ASODN targeting apollon gene could all suppress the growth of Lovo cells and induce apoptosis of these cells significantly (P < 0.05). After Lovo cells treated with apollon ASODN for 48 hours, the expression of the apollon mRNA level was suppressed significantly. And a marked concentration-dependent decline of cell proliferation and clone forming, increasing of cell apoptosis levels were observed. The percentage of G0/G1 phage cells was abated and that of S phage cells was increased and the Lovo cells arrested at S phage of the cell cycle detected with flow cytometry. Many Lovo cells stained with Hoechst 33258 exhibited apoptotic morphology such as cell shrinkage, nuclear condensation and nuclear fragmentation. Cell proliferation inhibition was detected and their chemo-therapeutic effects of 5-FU, DDP and EPI on Lovo cells combined with apollon ASODN (0.08 micromol x L(-1)) were enhanced independently compared with single 5-FU, DDP and EPI groups, and the sensitivity enhanced about 2.58, 4.47, and 5.33 times respectively. It can be concluded that ASODN targeting apollon can suppress the expression of apollon mRNA, and inhibit the proliferation, induce apoptosis, arrest cell cycle at S phase of colorectal cancer Lovo cells in vitro and enhance the chemo-sensitivity to 5-FU, DDP and EPI.

[Antisense oligonucleotides targeting protein kinase C alpha inhibits the proliferation of A549 cells].

OBJECTIVE: To investigate the effects of antisense oligonucleotides (ASODN) targeting protein kinase C alpha (PKCalpha) on the proliferation of A549 cells. METHODS: PKCalpha ASODN and random oligonucleotides (RODN) were transfected into A549 cells mediated by polyethyleneimine, and the proliferation and clone formation of A549 cells were detected by CCK-8 and clone formation assay, respectively. The expression of PKCalpha in the transfected cells was analyzed by RT-PCR and Western blotting. RESULTS: Compared with those in the control group, PEI group and PEI-RODN group, the proliferation and clone formation of A549 cells treated with ASODN targeting PKCalpha were significantly inhibited (P<0.05). The expressions of PKCalpha mRNA and protein in PKCalpha ASODN-transfected A549 cells were significantly lower than those in the other 3 groups (P<0.05). CONCLUSION: The PKCalpha ASODN mediated by PEI down-regutates the expression of PKCalpha gene and suppress the proliferation and clone formation of A549 cells.