| Title: |
Carbohydrate improves exercise capacity but does not affect subcellular lipid droplet morphology, AMPK and p53 signalling in human skeletal muscle |
| Authors: |
Fell, JM; Hearris, MA; Ellis, DG; Moran, JEP; Jevons, EFP; Owens, DJ; Strauss, JA; Cocks, MS; Louis, JB; Shepherd, SO; Morton, JP |
| Publisher Information: |
Wiley |
| Publication Year: |
2021 |
| Collection: |
Liverpool John Moores University: LJMU Research Online |
| Subject Terms: |
RC1200 Sports Medicine |
| Description: |
We examined the effects of carbohydrate (CHO) feeding on lipid droplet (LD) morphology, muscle glycogen utilisation and exercise‐induced skeletal muscle cell signalling. After a 36 h CHO loading protocol and pre‐exercise meal (12 and 2 g kg–1, respectively), eight trained males ingested 0, 45 or 90 g CHO h–1 during 180 min cycling at lactate threshold followed by an exercise capacity test (150% lactate threshold). Muscle biopsies were obtained pre‐ and post‐completion of submaximal exercise. Exercise decreased (P < 0.01) glycogen concentration to comparable levels (∼700 to 250 mmol kg–1 DW), though utilisation was greater in type I (∼40%) versus type II fibres (∼10%) (P < 0.01). LD content decreased in type I (∼50%) and type IIa fibres (∼30%) (P < 0.01), with greater utilisation in type I fibres (P < 0.01). CHO feeding did not affect glycogen or IMTG utilisation in type I or II fibres (all P > 0.05). Exercise decreased LD number within central and peripheral regions of both type I and IIa fibres, though reduced LD size was exclusive to type I fibres. Exercise induced (all P < 0.05) comparable AMPKThr172 (∼4‐fold), p53Ser15 (∼2‐fold) and CaMKIIThr268 phosphorylation (∼2‐fold) with no effects of CHO feeding (all P > 0.05). CHO increased exercise capacity where 90 g h–1 (233 ± 133 s) > 45 g h–1 (156 ± 66 s; P = 0.06) > 0 g h–1 (108 ± 54 s; P = 0.03). In conditions of high pre‐exercise CHO availability, we conclude CHO feeding does not influence exercise‐induced changes in LD morphology, glycogen utilisation or cell signalling pathways with regulatory roles in mitochondrial biogenesis. |
| Document Type: |
article in journal/newspaper |
| File Description: |
text |
| Language: |
English |
| ISSN: |
0022-3751 |
| Relation: |
https://researchonline.ljmu.ac.uk/id/eprint/15022/1/Carbohydrate%20improves%20exercise%20capacity%20but%20does%20not%20affect%20subcellular%20lipid%20droplet%20morphology,%20AMPK%20and%20p53%20signalling%20in%20human%20skeletal%20muscle.pdf; Fell, JM, Hearris, MA, Ellis, DG, Moran, JEP, Jevons, EFP, Owens, DJ, Strauss, JA, Cocks, MS, Louis, JB, Shepherd, SO and Morton, JP (2021) Carbohydrate improves exercise capacity but does not affect subcellular lipid droplet morphology, AMPK and p53 signalling in human skeletal muscle. The Journal of Physiology. ISSN 0022-3751 |
| DOI: |
10.1113/JP281127 |
| Availability: |
https://researchonline.ljmu.ac.uk/id/eprint/15022/; https://researchonline.ljmu.ac.uk/id/eprint/15022/1/Carbohydrate%20improves%20exercise%20capacity%20but%20does%20not%20affect%20subcellular%20lipid%20droplet%20morphology,%20AMPK%20and%20p53%20signalling%20in%20human%20skeletal%20muscle.pdf; https://doi.org/10.1113/JP281127 |
| Rights: |
cc_by |
| Accession Number: |
edsbas.A8095A33 |
| Database: |
BASE |