The Effects Of Antisense Oligonucleotide For C-myc, Antisense Eukaryotic Expression Vectors For C-myc And Antisense Recombinant Adenoviral Vector For C-myc On The Proliferation Of Rat Airway Smooth Muscle Cells

Many factors participate in the process of airway inflammation in asthma. These include antigens, inflammatory mediators and cytokines et al. Airway remodelling occurs with airway inflammation. So, the airway remodelling is one of early events in the process of asthma. Airway remodelling includes the thickening and shedding of epithelium, subepithelial collagen deposition, airway smooth muscle hypertrophy/hyperplasia and increased submucosal vascularity and remodelling. The airway smooth muscle hypertrophy and hyperplasia is one of important factors in the process of airway remodelling. Because airway smooth muscle hypertrophy and hyperplasia can increase bronchial hyperresponsiveness and increase irreversible airflow obstruction. Antiproliferation of airway smooth muscle cells may help the treatment for asthma.The stimulation of inflammatory mediators and cytokines to rat airway smooth muscle cells are conducted by different signal pathways, so, the extracellular signals can be conducted into cells. This will start or depress certain genes expression. The cell cycles started at the end of the process. Proto-oncogenes are the final pathway of signal conduction. Interruption the proto-oncogenes expression may have antiproliferative effect.Antisense nucleotides can disturb genes expression. This is one of effective gene therapy ways. Several studies have showed that antisense oligonucleotide for c-myc could inhibit proliferation of vascular smooth muscle cells, vascular endothelial cells and hepatocyte. Antisense oligonucleotide for c-myc could inhibit the expression of c-Myc and proliferating cell nuclear antigen (PCNA). Antisense recombinant adenovirus for protein kinase C could inhibit human airway smooth muscle cells proliferation. Injection of antisense IL-5 could suppress of lung eosinophilia and antigen-mediated airway hyperresponsiveness. In order to observe the antiproliferative effects of antisense c-myc on rat airway smooth muscle cells, we designed the follow studies:1. Antisense oligonucleotide for c-myc on the proliferation of rat airway smooth muscle cellsAntisense oligonucleotide for c-myc was artificially synthesized and transfected into rat airway smooth muscle cells by cationic lipid. Cell growth was assayed by way of MTT. RT-PCR was used to detect the expression of c-myc mRNA. c-Myc was observed by immunohistochemistry staining. The results showed that antisense oligonucleotide for c-myc could inhibit rat airway smooth muscle cells proliferation. This effect could last 6 days after antisense oligonucleotide was transfected into cells. The antiproliferative effect was related with the concentration of antisense oligonucleotide. With the increasement of antisense oligonucleotide concentration, the antiproliferative effect was also increased. Antisense oligonucleotide for c-myc could decrease the expression of c-myc mRNA. The translation of c-myc was decreased too.2. The relationship between antiproliferative effect of antisense oligonucleotide for c-myc and apoptosisAntisense oligonucleotide for c-myc was transfected into rat airway smoothmuscle cells. Cell growth was inhibited. Apoptosis bodies were examined after Giemsa's staining. Flow cytometry technology was used to detect apoptosis peak. DNA ladder was observed after total DNA agarose electrophoresis. The expression of apoptosis associated gene productions Bax and Bcl-2 were detected by immunohistochemistry staining. The results showed there was no apoptosis body 72 h after antisense oligonucleotide for c-myc was transfected. No apoptosis peak was detected by flow cytometry technology. DNA ladder was not found after total DNA agarose electrophoresis. There were no difference in the expression of apoptosis associated gene productions Bax and Bcl-2 in the different groups. No relationship between antiproliferative effect of antisense oligonucleotide for c-myc in rat airway smooth muscle cells and cell apoptosis.3. Construction of antisense eukaryotic expression vectors for c-myc an...