Select Skeletal Muscle mRNAs Related to Exercise Adaptation Are Minimally Affected by Different Pre-exercise Meals that Differ in Macronutrient Profile

Abstract

Background: Substantial research has been done on the impact of carbohydrate and fat availability on endurance exercise adaptation, though its role in the acute adaptive response to resistance exercise has yet to be fully characterized.Purpose: We aimed to assess the effects of a pre-resistance exercise isocaloric mixed meal containing different amounts of carbohydrates and fat, on post-resistance exercise gene expression associated with muscle adaptation.Methods: Thirteen young (age 21.2 ± 1.6 year), recreationally trained (VO2max 51.3 ± 4.8 ml/kg/min) men undertook an aerobic exercise session of 90-min continuous cycling (70% VO2max) in the morning with pre- and post-exercise protein ingestion (10 and 15 g casein in a 500 ml beverage pre- and post-exercise, respectively). Subjects then rested for 2 h and were provided with a meal consisting of either 3207 kJ; 52 g protein; 51 g fat; and 23 g carbohydrate (FAT) or 3124 kJ; 53 g protein; 9 g fat; and 109 g carbohydrate (CHO). Two hours after the meal, subjects completed 5 × 8 repetitions (80% 1-RM) for both bilateral leg press and leg extension directly followed by 25 g of whey protein (500 ml beverage). Muscle biopsies were obtained from the vastus lateralis at baseline (morning) and 1 and 3 h post-resistance exercise (afternoon) to determine intramuscular mRNA response.Results: Muscle glycogen levels were significantly decreased post-resistance exercise, without any differences between conditions. Plasma free fatty acids increased significantly after the mixed meal in the FAT condition, while glucose and insulin were higher in the CHO condition. However, PDK4 mRNA quantity was significantly higher in the FAT condition at 3 h post-resistance exercise compared to CHO. HBEGF, INSIG1, MAFbx, MURF1, SIRT1, and myostatin responded solely as a result of exercise without any differences between the CHO and FAT group. FOXO3A, IGF-1, PGC-1α, and VCP expression levels remained unchanged over the course of the day.Conclusion: We conclude that mRNA quantity associated with muscle adaptation after resistance exercise is not affected by a difference in pre-exercise nutrient availability. PDK4 was differentially expressed between CHO and FAT groups, suggesting a potential shift toward fat oxidation and reduced glucose oxidation in the FAT group.

Mechanical loading of bioengineered skeletal muscle in vitro recapitulates gene expression signatures of resistance exercise in vivo

“…These genes were therefore analyzed at 0.5, 3, and 24 h post-loading in bioengineered mouse muscle to enable a direct comparison with humans after acute RE. First, the majority of these genes predominantly increased at 3 h post-loading and returned to basal levels at 24 h. This temporal gene regulatory profile has been observed several times in response to exercise in vivo in which gene expression tends to peak at 3-8 h post-exercise (Barrès et al, 2012;Chen et al, 2002;Drummond et al, 2008;Knuiman et al, 2018;Kuang et al, 2020) and generally returns to basal levels within 24 h Liu et al, 2010;Yang et al, 2005).…”

“…It is also worth noting that analysis of human muscle involved pooling transcriptomic datasets across 110 biopsies (37 pre/57 post after outlier removal) over multiple studies (Turner et al, 2019b ), and therefore encompassed all timepoints from immediately post and up to 24 h post‐acute RE. Where, gene expression is typically greatest at 3–8 h post exercise (Barrès et al, 2012 ; Chen et al, 2002 ; Drummond et al, 2008 ; Knuiman et al, 2018 ; Kuang et al, 2020 ) and generally returns to basal levels within 24 h (Egan & Zierath, 2012 ; Liu et al, 2010 ; Yang et al, 2005 ). Therefore, the majority of transcriptional alterations detected at 3 h in the bioengineered muscle may also be exemplifying this temporal activation in gene expression post‐loading.…”

Cytoskeletal Remodeling Mimics Endothelial Response to Microgravity

“…Cytoskeletal remodeling is a common feature of eukaryotic cells exposed to real and simulated microgravity, including endothelial cells ( Cotrupi et al, 2005 ; Versari et al, 2013 ; Barravecchia et al, 2018 ). In HUVEC grown in the RWV, we have shown that cytoskeletal disorganization plays a role in triggering mitophagy ( Locatelli et al, 2020 ).…”

“…In this paper, we investigated the role of cytoskeletal disorganization in orchestrating endothelial response to simulated microgravity. Because of the heterogeneity of the endothelium, we used two different types of EC, i.e., human endothelial cells from umbilical vein (HUVEC) and human dermal microvascular endothelial cells (HDMEC), a model of macro- and microvascular EC, respectively, which have been used for studies in real and simulated microgravity ( Shi et al, 2012 ; Grenon et al, 2013 ; Versari et al, 2013 ; Barravecchia et al, 2018 ; Cazzaniga et al, 2019 ; Locatelli et al, 2020 ).…”

Relieving Cellular Energy Stress in Aging, Neurodegenerative, and Metabolic Diseases, SIRT1 as a Therapeutic and Promising Node

“…These effectors include the activators of pyruvate dehydrogenase kinase 4 (PDK4), forkhead box O1 (FoxO1), ERRα, and PPARs gene expression. And enhanced PDK4 can phosphorylate PDH to inactivate it and prevent pyruvate from entering TCA, converting cells from glucose metabolism to lipid metabolism and then meet the energy needs of exercise (Knuiman et al, 2018 ). In addition, as a downstream factor activated by the SIRT1-PGC-1α axis, TFAM can play a role in diseases such as diabetes and diabetic peripheral neuropathy by enhancing the function of mitochondria, promote the complete oxidation of fatty acids in mitochondria, and provide a large number of sources of ATP for cells (Chandrasekaran et al, 2019 ).…”