Murine Fibroblast NIH3T3 Cells Research Articles

Aurothioglucose inhibits induced NF-kB and AP-1 activity by acting as an IL-1 functional antagonist

We have designed a series of recombinant CAT genes to study IL-1 signal transduction in murine fibroblast NIH 3T3 cells. We demonstrate that the HSV thymidine kinase (tk) promoter does not respond to IL-1, but that IL-1 induction of this promoter is observed after insertion of either NF-kB or AP-1 binding sites upstream of the HSV tk cap-site. We have studied the effects of indomethacin, dexamethasone and aurothioglucose (which have been used in the treatment of patients affected by rheumatoid arthritis) in the IL-1 inducible CAT assay. We show that aurothioglucose or dexamethasone is able to inhibit IL-1 induced CAT activity whereas a non-steroidal anti-inflammatory drug (indomethacin) is inactive. Order of addition experiments indicate that aurothiglucose, which has disease-modifying activity in treated patients, ats as an IL-1 functional antagonist in this system.

Enhanced in vitro growth of murine fibroblast cells and preimplantation embryos cultured in medium supplemented with an amphipathic peptide.

Preliminary studies on the proliferative effects of lytic peptides were carried out using NIH 3T3 murine fibroblast cells and human lymphocytes. Cells were cultured in various concentrations of three different amphipathic peptides (SB-37, Shiva-1, and Vishnu), and enhanced proliferation was determined by uptake of 3H-thymidine with treated cells compared with control cultures. Enhanced proliferation of 3T3 cells was observed in cultures containing 50 microM or less SB-37. The primary study consisted of 263 four-cell- to eight-cell-stage mouse embryos from naturally bred mice and incubated in Whitten's medium containing 0.2, 1, or 10 microM of the amino terminus of an amphipathic cecropin B analog (Vishnu) or in Whitten's medium alone. Embryos were cultured to the hatched blastocyst stage, and effect of treatment was determined by the rate of growth to that stage of development. Statistical analysis revealed that culture in all three levels of Vishnu significantly accelerated in vitro growth of these stages of preimplantation embryos compared with controls. These results indicate that Vishnu promotes increased cleavage rates of embryos in vitro. A growth factor receptor clustering mechanism of action is proposed. This peptide may have some potential as an embryo culture medium additive to enhance in vitro growth rate.