The role of cyadox and recombinant growth hormone (rGH) on the promotion of growth through epigenetics

Abstract Background: Cyadox is an effective growth-promoting antibiotic, which is similar to the role of recombinant growth hormone (rGH). Current studies have shown that cyadox can promote animal growth through altering intestinal microflora, improving protein utilization and increasing protein synthesis. Increasing evidence suggests that epigenetics are also closely related to growth. However, the potential role of epigenetics in the cyadox for growth has not been explored. Results: Here, we used recombinant growth hormone (rGH) and cyadox to study the relationship between growth and changes in epigenetics including DNA methylation, histone modification and chromatin structure. Bisulfite DNA sequencing (BSP) assay suggested that cyadox and rGH treatments increased IGF-1 expression partially by hypomethylation at CpG sites within the promoter region of IGF-1, which was regulated by DNA methyltransferases (DNMTs). We also observed an enrichment of H3K4me3 and H3K27ac at the promoter regions of IGF-1 by ChIP-qPCR assay, which contributed to an increase in IGF-1 transcription. In addition, immunofluorometric assay displayed cellular accessible chromatin structure following the treatment of cyadox and rGH, facilitating the combination of transcription factors and DNA and thus enhancing gene transcription. Conclusions: Taken together, our findings indicated that cyadox and rGH promote cell growth partially through epigenetic changes, providing a prospect for the development of animal growth-promoting drugs in the future.