Dataset Information

Insight Into the Metabolic Adaptations of Electrically Pulse-Stimulated Human Myotubes Using Global Analysis of the Transcriptome and Proteome.

ABSTRACT: Electrical pulse stimulation (EPS) has proven to be a useful tool to interrogate cell-specific responses to muscle contraction. In the present study, we aimed to uncover networks of signaling pathways and regulatory molecules responsible for the metabolic effects of exercise in human skeletal muscle cells exposed to chronic EPS. Differentiated myotubes from young male subjects were exposed to EPS protocol 1 (i.e. 2 ms, 10 V, and 0.1 Hz for 24 h), whereas myotubes from middle-aged women and men were exposed to protocol 2 (i.e. 2 ms, 30 V, and 1 Hz for 48 h). Fuel handling as well as the transcriptome, cellular proteome, and secreted proteins of EPS-treated myotubes from young male subjects were analyzed using a combination of high-throughput RNA sequencing, high-resolution liquid chromatography-tandem mass spectrometry, oxidation assay, and immunoblotting. The data showed that oxidative metabolism was enhanced in EPS-exposed myotubes from young male subjects. Moreover, a total of 81 differentially regulated proteins and 952 differentially expressed genes (DEGs) were observed in these cells after EPS protocol 1. We also found 61 overlapping genes while comparing the DEGs to mRNA expression in myotubes from the middle-aged group exposed to protocol 2, assessed by microarray. Gene ontology (GO) analysis indicated that significantly regulated proteins and genes were enriched in biological processes related to glycolytic pathways, positive regulation of fatty acid oxidation, and oxidative phosphorylation, as well as muscle contraction, autophagy/mitophagy, and oxidative stress. Additionally, proteomic identification of secreted proteins revealed extracellular levels of 137 proteins were changed in myotubes from young male subjects exposed to EPS protocol 1. Selected putative myokines were measured using ELISA or multiplex assay to validate the results. Collectively, our data provides new insight into the transcriptome, proteome and secreted proteins alterations following in vitro exercise and is a valuable resource for understanding the molecular mechanisms and regulatory molecules mediating the beneficial metabolic effects of exercise.

SUBMITTER: Mengeste AM

PROVIDER: S-EPMC9298736 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Regular physical exercise evokes profound physiological responses which are strongly associated with many health benefits. However, the details of cellular networks and mechanisms underlying the adaptive responses to exercise remain to be elucidated. We have previously shown the usefulness of electrical pulse stimulation (EPS) to investigate metabolic effects of exercise in cultured human myotubes. The aim of the present study was to uncover networks of signaling pathways and regulatory molecules responsible for the metabolic effects of exercise in human skeletal muscle cells exposed to chronic EPS. Differentiated myotubes were subjected to two different EPS protocols (protocol 1; 2 ms, 10 V, 0.1 Hz for 24 h or protocol 2; 2 ms, 30 V, and 1 Hz for 48 h). Fuel handling was assessed using radiolabeled substrates. The transcriptome, cell proteome, and secreted proteins from EPS-treated and untreated myotubes were analyzed using a combination of high-throughput RNA sequencing, microarray, and high-resolution liquid chromatography mass spectrometry. Independent validation of selected putative myokines were measured using ELISA or multiplex assay. Oxidative metabolism was enhanced in human myotubes exposed to EPS protocol 1. A total of 81 differentially regulated proteins and 952 differentially expressed genes (DEGs) were observed in the cells after EPS protocol 1. Gene ontology (GO) analysis indicated that significantly regulated proteins and genes were enriched in biological processes related to glycolytic pathways, positive regulation of fatty acid oxidation, and oxidative phosphorylation, as well as muscle contraction, autophagy/mitophagy, and oxidative stress. Moreover, proteomic identification of secreted proteins revealed extracellular levels of 137 proteins were changed in myotubes subjected to EPS protocol 1. We also found some degree of overlap between the DEGs found in myotubes submitted to EPS protocol 1 and protocol 2. Among these DEGs was a myokine, leukemia inhibitory factor, which showed to enhance the glucose uptake in skeletal muscle cells, indicating autocrine mechanism to maintain metabolic homeostasis. Collectively, our data provides new insight into the transcriptome, proteome and secreted proteins alterations following in vitro exercise and is a valuable resource for understanding the molecular mechanisms and regulatory molecules mediating the beneficial metabolic effects of exercise.

Project description:BackgroundSkeletal muscle from lean and obese subjects elicits differential adaptations in response to exercise/muscle contractions. In order to determine whether obesity alters the adaptations in mitochondrial dynamics in response to exercise/muscle contractions and whether any of these distinct adaptations are linked to alterations in insulin sensitivity, we compared the effects of electrical pulse stimulation (EPS) on mitochondrial network structure and regulatory proteins in mitochondrial dynamics in myotubes from lean humans and humans with severe obesity and evaluated the correlations between these regulatory proteins and insulin signaling.MethodsMyotubes from human skeletal muscle cells obtained from lean humans (body mass index, 23.8 ± 1.67 kg·m-2) and humans with severer obesity (45.5 ± 2.26 kg·m-2; n = 8 per group) were electrically stimulated for 24 h. Four hours after EPS, mitochondrial network structure, protein markers of insulin signaling, and mitochondrial dynamics were assessed.ResultsEPS enhanced insulin-stimulated AktSer473 phosphorylation, reduced the number of nonnetworked individual mitochondria, and increased the mitochondrial network size in both groups (P < 0.05). Mitochondrial fusion marker mitofusin 2 was significantly increased in myotubes from the lean subjects (P < 0.05) but reduced in subjects with severe obesity (P < 0.05). In contrast, fission marker dynamin-related protein 1 (Drp1Ser616) was reduced in myotubes from subjects with severe obesity (P < 0.05) but remained unchanged in lean subjects. Reductions in DrpSer616 phosphorylation were correlated with improvements in insulin-stimulated AktSer473 phosphorylation after EPS (r = -0.679, P = 0.004).ConclusionsOur data demonstrated that EPS induces more fused mitochondrial networks, which are associated with differential adaptations in mitochondrial dynamic processes in myotubes from lean humans and human with severe obesity. It also suggests that improved insulin signaling after muscle contractions may be linked to the reduction in Drp1 activity.

Dataset Information

Insight Into the Metabolic Adaptations of Electrically Pulse-Stimulated Human Myotubes Using Global Analysis of the Transcriptome and Proteome.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets