Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

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Supplemental carnitine affects the microRNA expression profile in skeletal muscle of obese Zucker rats

ABSTRACT: Background In the past, numerous studies revealed that supplementation with carnitine has multiple effects on performance characteristics and gene expression in livestock and model animals. The molecular mechanisms underlying these observations are still largely unknown. Increasing evidence suggests that microRNAs (miRNAs), a class of small non-coding RNA molecules, play an important role in post-transcriptional regulation of gene expression and thereby influencing several physiological and pathological processes. Based on these findings, the aim of the present study was to investigate the influence of carnitine supplementation on the miRNA expression profile in skeletal muscle of obese Zucker rats using miRNA microarray analysis. Results miRNA expression profiling in skeletal muscle revealed a subset of 152 miRNAs out of the total number of miRNAs analysed (259) were identified to be differentially regulated (adjusted P-value ˂ 0.05) by carnitine supplementation. Compared to the obese control group, 111 miRNAs were up-regulated and 41 down-regulated by carnitine supplementation (adjusted P-value ˂ 0.05). 14 of these miRNAs showed a log2 ratio ≥ 0.5 and 7 miRNAs showed a log2 ratio ≤ -0.5 (adjusted P-value ˂ 0.05). Conclusion The present study shows for the first time that supplementation of carnitine affects a large set of miRNAs in skeletal muscle of obese Zucker rats suggesting a novel mechanism through which carnitine exerts its multiple effects on gene expression, which were observed during the past. For microarray analyses, six RNA samples each, for the obese control group (n = 6) and the obese carnitine group (n = 6), were prepared from skeletal muscle tissue.

ORGANISM(S): Rattus norvegicus

SUBMITTER: Janine Keller

PROVIDER: E-GEOD-58537 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Supplemental carnitine affects the microRNA expression profile in skeletal muscle of obese Zucker rats

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