After being weaned, pups were housed in collective cages and were given the standard pellet diet until the end of the experiment. Age-matched virgin female rats, subjected to the same dietary regimens for the first 12 days of experiment as the pregnant rats, were studied in parallel. Rats were sacrificed by decapitation and after their exsanguinations liver and lumbar adipose tissue were dissected, placed in liquid nitrogen, and, after weighing, kept at -80��C. Offspring at 1 day of age and male adults of 12 months were sacrificed and their liver was collected as indicated above. Liver and adipose tissues were used for miRNA analysis. To determine whether dietary consumption of a particular fatty acid during the first 12 days of pregnancy influences the expression of specific miRNAs, we performed an unbiased genomewide miRNA analysis of liver samples. In pregnant liver tissue, 700 Ponatinib Src-bcr-Abl inhibitor miRNAs were measured by qRT-PCR. 15 miRNAs were found to be significantly modulated by any of the source of fatty acids used. To test whether the effect of a particular fatty acid on miRNA expression was observed in other tissues, we also analyzed the adipose tissue whole miRNome by qRT-PCR. In lumbar adipose tissue of pregnant, we observed 13 miRNAs that were significantly modulated by any kind of fatty acids. Again, to test whether the same effects were observed in virgin rats receiving the different diets, we evaluated the 13 miRNAs which significantly changed in pregnant rats. In the adipose tissue of virgin rats, only four of the miRNA previously analyzed in pregnant rats changed significantly. Understanding the molecular consequences of specific fatty acid supplementations during the first half of pregnancy��in terms of offspring development��is important to promote and/or reinforce recommendations of the consumption of adequate amounts of a particular type of fatty acid. This study provides in vivo evidence that different miRNAs are BAY 73-4506 induced or repressed in the liver and adipose tissues of pregnant and virgin rats according to diets added with different types of fatty acids. We firstly demonstrated that miRNA expression in the liver is distinctively regulated by the type of fatty acid consumed and, secondly, we found that miRNAs expression in adipose tissue is different from their expression in liver, after the intake of diets with different fatty acid profiles. These results suggest that it is important to assess the expression of miRNAs tissue-by-tissue, in order to assess the final effect of the intake of diets with different types of fatty acids. Not surprisingly, tissue distribution or development stage strongly influences miRNA function. Indeed, some miRNAs are highly expressed in or restricted to a specific tissue or cell type.