These small RNA elements are powerful post-transcriptional regulators in altering gene expression to orchestrate the normalization of physiological activities under stress conditions

These small RNA elements are powerful post-transcriptional regulators in altering gene expression to orchestrate the normalization of physiological activities under stress conditions. The data demonstrate for the first time a critical function of microRNAs in fine-tuning the regulation of glucose transport in skeletal muscle. Chronic starved conditions (IPGR) in sk. muscle up-regulates microRNA changing the target protein expression patterns, such as SMAD4, to alter the glucose transport pathways for the survival. The innovative outcome of this paper identifies a critical pathway (TGF-beta) that may act negatively for the mammalian glucose transport machinery. Introduction Tissue-specific, developmental and stress-induced expression patterns of a group of microRNAs regulate essential functions in biological systems [1]C[3]. These small RNA elements are powerful post-transcriptional regulators in altering gene BDP9066 expression to orchestrate the normalization of physiological activities under stress conditions. Thus, it is likely that aberrant expression of microRNA leads to disease conditions including carcinogenesis and metabolic syndromes. The glucose transporters in peripheral tissues, such as skeletal muscles, are pivotal in regulating glucose transport activity and thus balance glucose homeostasis in the blood. In response to insulin, ischemia and exercise, GLUT4 molecules translocate into the plasma membrane and orchestrate facilitative glucose transport into the cells [4]. Insulin-dependent translocation of GLUT4 vesicles into the plasma membrane is the major mechanism by which glucose uptake into the sk. muscles and NFKBI cardiac muscle tissues can be often regulated [5], [6]. Aberration in skeletal muscle glucose transport pathway can cause metabolic diseases including insulin resistance and diabetes [7]C[12]. Groups of tissue-specific (e.g., miR-1, miR-206, miR-208) and non-tissue-specific (e.g., miR-29a, miR-23a) microRNAs have been found to control skeletal muscle development in growth and differentiation [13]C[19]. The tissue-specific microRNAs can regulate glucose homeostasis and the pathophysiology of metabolic disease [20]C[22]. The expression of GLUT4, both transcriptional and translational, and its membrane trafficking from cytoplasmic vesicles upon insulin signaling, is critical in glucose transport activity of sk. muscles in both normal physiological and metabolic disease conditions [23]C[26]. Intrauterine growth restriction (IUGR) model mediated by various causes (e.g., semi-calorie food restriction, protein restriction, hypoxic condition in rodents) has been shown to alter the insulin signaling in offspring, leading to the development of insulin resistance in the sk. muscles [27]C[31]. The transcriptional changes of GLUT4 expression in female rat under these conditions has been attributed to the epigenetic changes including histone modifications, histone deacetylation (HDAC recruitment) and other associated changes in key enzymes of this process [32]. The histone code modifications were also been inferred in IGF1 transcription of IUGR rat offspring in programmed obesity [33]. The improper nutrition in the early intrauterine growth phase can have a deleterious effect on the adult life, such as metabolic syndrome [34]. All of these observations raise the possibility of trans-generational epigenetic changes that may have occurred in the intrauterine environment upon nutritional interruptions/aberrations, therefore the offspring get susceptible to the development of phenotype leading to metabolic disorders. While investigating the GLUT4 status of the male counterpart skeletal muscle mass, no switch was observed in total GLUT4 manifestation overall in comparison to the female counterpart in IPGR offspring. This differential, gender-specific transcriptional control of GLUT4 under this food restriction protocol led me to investigate the global microRNA gene manifestation pattern in male sk. muscle tissue and thus the involvement of these small regulatory genetic elements in the glucose transport process. MiR-223 and miR-133 regulate the manifestation of glucose transporter 4 in cardiomyocytes either by directly focusing on GLUT4 3UTR or indirectly focusing on additional protein-coding mRNA, e.g., KLF15 [35], [36]. MiR-223 up-regulation in cardiomyocytes causes the phosphatidylinositol-3-kinase (PI-3K) self-employed increase of glucose transport activity [36]. The miR-29 group of microRNAs was found to be up-regulated in muscle mass and fat cells of GotoCKakizaki rats, a non-obese rat model of.6, ?,11).11). of microRNAs in fine-tuning the rules of glucose transport in skeletal muscle mass. Chronic starved conditions (IPGR) in sk. muscle mass BDP9066 up-regulates microRNA changing the prospective protein manifestation patterns, such as SMAD4, to alter the glucose transport pathways for the survival. The innovative end result of this paper identifies a critical pathway (TGF-beta) that may take action negatively for the mammalian glucose transport machinery. Intro Tissue-specific, developmental and stress-induced manifestation patterns of a group of microRNAs regulate essential functions in biological systems [1]C[3]. These small RNA elements are powerful post-transcriptional regulators in altering gene manifestation to orchestrate the normalization of physiological activities under stress conditions. Thus, it is likely that aberrant manifestation of microRNA prospects to disease conditions including carcinogenesis and metabolic syndromes. The glucose transporters in peripheral cells, such as skeletal muscle tissue, are pivotal in regulating glucose transport activity and thus balance glucose homeostasis in the blood. In response to insulin, ischemia and exercise, GLUT4 molecules translocate into the plasma membrane and orchestrate facilitative glucose transport into the cells [4]. Insulin-dependent translocation of GLUT4 vesicles into the plasma membrane is the major mechanism by which glucose uptake into the sk. muscle tissue and cardiac muscle tissues can be often regulated [5], [6]. Aberration in skeletal muscle mass glucose transport pathway can cause metabolic diseases including insulin resistance and diabetes [7]C[12]. Groups of tissue-specific (e.g., miR-1, miR-206, miR-208) and non-tissue-specific (e.g., miR-29a, miR-23a) microRNAs have been found to control skeletal muscle mass development in growth and differentiation [13]C[19]. The tissue-specific microRNAs can regulate glucose homeostasis and the pathophysiology of metabolic disease [20]C[22]. The manifestation of GLUT4, both transcriptional and translational, and its membrane trafficking from cytoplasmic vesicles upon insulin signaling, is critical in glucose transport activity of sk. muscle tissue in both normal physiological and metabolic disease conditions [23]C[26]. Intrauterine growth restriction (IUGR) model mediated by numerous causes (e.g., semi-calorie food restriction, protein restriction, hypoxic condition in rodents) offers been shown to BDP9066 alter the insulin signaling in offspring, leading to the development of insulin resistance in the sk. muscle tissue [27]C[31]. The transcriptional changes of GLUT4 manifestation in female rat under these conditions has been attributed to the epigenetic changes including histone modifications, histone deacetylation (HDAC recruitment) and additional associated changes in important enzymes of this process [32]. The histone code modifications were also been inferred in IGF1 transcription of IUGR rat offspring in programmed obesity [33]. The improper nutrition in the early intrauterine growth phase can have a deleterious effect on the adult life, such as metabolic syndrome [34]. All of these observations raise the possibility of trans-generational epigenetic changes that may have occurred in BDP9066 the intrauterine environment upon nutritional interruptions/aberrations, therefore the offspring get susceptible to the development of phenotype leading to metabolic disorders. BDP9066 While investigating the GLUT4 status of the male counterpart skeletal muscle mass, no switch was observed in total GLUT4 manifestation overall in comparison to the female counterpart in IPGR offspring. This differential, gender-specific transcriptional control of GLUT4 under this food restriction protocol led me to investigate the global microRNA gene manifestation pattern in male sk. muscle tissue.