The effect of lithium and dexamethasone on fetal rat metatarsal bones transcriptome

While dexamethasone impairs bone growth and adds to the development of osteoporosis, lithium enhances cell renewal. The aim of this project was to explore the genes and pathways affected by adding dexamethasone, lithium or both to the medium in which fetal rat metatarsal bones were cultivated. RNA sequencing and differential gene expression analysis were implemented to describe the transcriptome of the metatarsals. We identified significant opposite as well as independent effects of the substances on several cellular pathways. This may open up to identify the mechanisms of dexamethasone induced bone growth and structure impairment and possible preventive measures. Overall design: Primary cultured fetal rat metatarsal bones were incubated in one of the four conditions: standard medium only (control sample, C), standard medium + dexamethason (Dex), standard medium + lithium (Li), standard medium + dexamethason and lithium (DL), at 37°C in 5% CO2 for 72 hours. All samples were prepared in triplicates.