SHIFTS IN MICRORNA EXPRESSION PROFILES WITHIN SKELETAL MUSCLE AND ADIPOSE ACROSS THE LIFESPAN

Skeletal muscle and adipose tissues are both involved in regulation of metabolism. In the skeletal muscle-adipose tissue crosstalk, exosomes may play an important role but the main components of exosomes are not clear. In this study, we found skeletal muscle-derived exosomes can inhibit adipogenesis of porcine preadipocytes. We identified microRNA expression profiles of muscle exosomes and adipose exosomes by high-throughput sequencing. There were 104 (both novel and known microRNAs) microRNAs differentially expressed (DE miRNAs) between M-EXO (muscle-derived exosomes) and A-EXO (adipose–derived exosomes) groups. A total of 2,137 target genes of DE miRNAs for M-EXO and 2,004 target genes of DE miRNAs for A-EXO were detected. Bioinformatic analyses revealed that some DE miRNAs of M-EXO (especially miR-221-5p) were mainly enriched in lipid-related metabolism processes. The findings may serve as a fundamental resource for understanding the detailed functions of exosomes between the skeletal muscle-adipose crosstalk and the potential relationship between skeletal muscle atrophy and obesity.

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Analysis of microRNA expression during the torpor-arousal cycle of a mammalian hibernator, the 13-lined ground squirrel

Physiological Genomics ◽

10.1152/physiolgenomics.00005.2016 ◽

2016 ◽

Vol 48 (6) ◽

pp. 388-396 ◽

Cited By ~ 19

Author(s):

Cheng-Wei Wu ◽

Kyle K. Biggar ◽

Bryan E. Luu ◽

Kama E. Szereszewski ◽

Kenneth B. Storey

Keyword(s):

Skeletal Muscle ◽

Ground Squirrel ◽

Muscle Development ◽

Expression Profiles ◽

Ground Squirrels ◽

Microrna Expression ◽

Metabolic Reprogramming ◽

Skeletal Muscle Atrophy ◽

Tissue Specific ◽

Go Annotation

Hibernation is a highly regulated stress response that is utilized by some mammals to survive harsh winter conditions and involves a complex metabolic reprogramming at the cellular level to maintain tissue protections at low temperature. In this study, we profiled the expression of 117 conserved microRNAs in the heart, muscle, and liver of the 13-lined ground squirrel ( Ictidomys tridecemlineatus) across four stages of the torpor-arousal cycle (euthermia, early torpor, late torpor, and interbout arousal) by real-time PCR. We found significant differential regulation of numerous microRNAs that were both tissue specific and torpor stage specific. Among the most significant regulated microRNAs was miR-208b, a positive regulator of muscle development that was found to be upregulated by fivefold in the heart during late torpor (13-fold during arousal), while decreased by 3.7-fold in the skeletal muscle, implicating a potential regulatory role in the development of cardiac hypertrophy and skeletal muscle atrophy in the ground squirrels during torpor. In addition, the insulin resistance marker miR-181a was upregulated by 5.7-fold in the liver during early torpor, which supports previous suggestions of hyperinsulinemia in hibernators during the early stages of the hibernation cycle. Although microRNA expression profiles were largely unique between the three tissues, GO annotation analysis revealed that the putative targets of upregulated microRNAs tend to enrich toward suppression of progrowth-related processes in all three tissues. These findings implicate microRNAs in the regulation of both tissue-specific processes and general suppression of cell growth during hibernation.

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Identification of Tumorigenic and Prognostic Biomarkers in Colorectal Cancer Based on microRNA Expression Profiles

BioMed Research International ◽

10.1155/2020/7136049 ◽

2020 ◽

Vol 2020 ◽

pp. 1-8

Author(s):

Yuntao Shi ◽

Yingying Zhuang ◽

Jialing Zhang ◽

Mengxue Chen ◽

Shangnong Wu

Keyword(s):

Target Genes ◽

Cox Regression ◽

Expression Profiles ◽

Survival Rates ◽

Enrichment Analysis ◽

Functional Enrichment Analysis ◽

Risk Groups ◽

Normal Mucosa ◽

Microrna Expression ◽

Functional Enrichment

Objective. Although noncoding RNAs, especially the microRNAs, have been found to play key roles in CRC development in intestinal tissue, the specific mechanism of these microRNAs has not been fully understood. Methods. GEO and TCGA database were used to explore the microRNA expression profiles of normal mucosa, adenoma, and carcinoma. And the differential expression genes were selected. Computationally, we built the SVM model and multivariable Cox regression model to evaluate the performance of tumorigenic microRNAs in discriminating the adenomas from normal tissues and risk prediction. Results. In this study, we identified 20 miRNA biomarkers dysregulated in the colon adenomas. The functional enrichment analysis showed that MAPK activity and MAPK cascade were highly enriched by these tumorigenic microRNAs. We also investigated the target genes of the tumorigenic microRNAs. Eleven genes, including PIGF, TPI1, KLF4, RARS, PCBP2, EIF5A, HK2, RAVER2, HMGN1, MAPK6, and NDUFA2, were identified to be frequently targeted by the tumorigenic microRNAs. The high AUC value and distinct overall survival rates between the two risk groups suggested that these tumorigenic microRNAs had the potential of diagnostic and prognostic value in CRC. Conclusions. The present study revealed possible mechanisms and pathways that may contribute to tumorigenesis of CRC, which could not only be used as CRC early detection biomarkers, but also be useful for tumorigenesis mechanism studies.

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