ABSTRACT
Objective Bacterial DNA is a pathogen-derived molecule which can regulate the innate immune system by stimulating NF-κB activation. The activity of bacterial DNA relies on its content of unmethylated CpG dinucleotides in particular base contexts("CpG motif"). In light of the pivotal role played by NF-κB in osteoclast differentiation, the ability of CpG oligodeoxynucleotides (CpG ODN) coming from bacterial DNA to modulate osteoclastogenesis was studied. Methods Bone marrow mononuclear cells (BMM) were purified from Balb/c mice, cultured in α-MEM media containing 10% FCS in the presence of mouse M-CSF, with either RANKL or ODNs for 5 days. Osteoclast formation was evaluated on day 5 according to TRAP and May-Grunwald-Giemsa staining. Results CpG ODN alone could induce osteoclast formation in the low degree in BMM culture. The relationship between CpG ODN and RANKL was that CpG ODN could inhibit RANKL-induced osteoclastogenesis when present from the beginning of BMM culture, but strongly increased RANKL-induced osteoclastogenesis in RANKL-pretreated BMMs. Conclusion The mechanism of CpG ODN regulating osteoclast differentiation was bidirectional, which might be a potential therapy for treating metabolic bone disease.
ABSTRACT
Purpose:To investigate the effect of in vitro antisense oligodeoxynucleotide of cyclin D 1 on the cyclin D 1 gene expression and cell proliferation of human stomach adenocarcinoma cell BGC 823 cell line.Methods:Phosphorothioate cyclin D 1 ASODN and random oligodeoxynucleotide (RODN) were synthesized and transfected into BGC 823 Cells. Their effects on cell proliferation were examined by MTT method,RT PCR method,immunohistochemical study.Results:Cyclin D 1 ASODN could significantly inhibit the growth of BGC 823 Cell lines.The RODN showed no such effect.The inhibition peaked at 48 hour after transfection by MTT method and was dose dependent.ASODN could downregulate the expression levels of cyclin D 1 mRNA and protein by RT PCR method and immunohistochemical study respectively.Conclusions:The data suggested that ASODN could specifically inhibit the expression of cyclin D 1 mRNA and protein and regulate cell cycle and cell proliferation of BGC 823 cells. [