The transcriptome of muscle and liver is responding differently to a combined trenbolone acetate and estradiol implant in cattle

In the present study, an attempt to compare bovine transcriptome of two different tissue matrices (liver and muscle) treated with the same molecules (trenbolone acetate (TBA) and estradiol (E2)) was carried out in order to understand the response of different tissues to the same treatment on a genomic/transcriptomic level. The primary aim of this study was to compare, via transcriptomic approach, the response of both muscle and liver to anabolic steroids, and to point out the main differences and similarities between both matrices. In addition, a second aim was to list out the main differentially expressed (DE) genes that can be used as a “pool” for biomarker investigations in the future. A bovine oligo microarray platform (GPL7053) was used to profile gene expression from thirty (30) bovine liver and muscle (biceps brachii) samples. Isolated and purified total RNAs were individually hybridized to the Agilent bovine V1 4x44k DNA microarray. The comparison of untreated and treated bovine transcriptomes revealed a set of differentially expressed genes. After functional analysis and qPCR validation, the result showed that the two transcriptomes showed completely different patterns, in terms of altered pathways and involved biological processes, following the treatment with anabolic steroids. However, they had 20 commonly expressed genes in-between. A total of 30 animals was used in this study. Animals were randomly divided into two groups of 15 animals each. The first group was used as a control (CTRL), the second was treated for 71 days with 200 mg trenbolone acetate (TBA) + 40 mg estradiol (E2) formulated together in a slow-release subcutaneous ear implant. Following completion of the treatment, animals were slaughtered and tissue aliquots from both liver and muscle tissues were taken and stored for further use. All samples yielded high quality RNA that was tested prior the microarray setup.