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| Author(s): |
Guilherme Defante Telles
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Escola de Educação Física e Esportes (EEFE/BT) |
| Defense date: | 2019-10-18 |
| Examining board members: |
Carlos Ugrinowitsch;
Carlos Roberto Bueno Júnior;
Edilamar Menezes de Oliveira;
Eduardo Oliveira de Souza
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| Advisor: | Carlos Ugrinowitsch |
| Abstract | |
DNA Methylation in myogenic genes related to satellite cells (SC) activation/proliferation/differentiation is a mechanism regarded to explain the lower muscle gains with concurrent exercise (CE) Training compared to resistance exercise (RE) Training alone, a phenomenon known as Interference Effect. Aim: To determine and compare the methylation and the mRNA expression levels of the myogenic regulatory factors (MyoD, Myf5, MYF6) and mitochondrial-related genes (PGC-1, TFAM, PPAR-) after Resistance Exercise (RE), Endurance Exercise (EE) and Concurrent Exercise (CE). Methods: 9 untrained young men volunteered to participate in a randomized and counterbalanced cross over design. Each volunteer performed a bout of RE, EE and CE. The RE was consisted of 2 exercises (Leg Press 45 and Leg extension), 2x8-12 maximum repetitions with 60s rest. In the EE condition participants performed 12 x 1 min sprints at 100% of the vVO2max with 1 minute rest at 50% of vVO2max. In the CE condition participants performed the RE and EE routines in the same exercise session. Twelve muscle samples were taken: immediately before, and 3 times after each exercise session (immediately (0h), 4 hours and 8 hours). Results: MYOD1 presented lower levels of DNA methylation after the EE bout 4H and 8H when compared to PRE, as well as at 8H when compared to 0H. It was also found a lower methylation percentage 4H hours after EE when compared to RE at the same time point. MYF5 and MYF6 methylation levels decreased significantly at 4H and 8H after the three conditions (main effect of time) compared to PRE and 0H. MYOD1 mRNA expression was increased 4H after all training sessions, when compared to PRE exercise values, and also increased at 8H when compared to the PRE, 0H and 4H. There was also a main effect of time for MYF5 gene expression, which showed lower mRNA levels at 4H when compared to 0H, returning to baseline- like values with a significant increase in 8H. MYF6 gene mRNA expression was higher under all conditions at 4H compared to PRE and 0H. Final considerations: Collectively, our results indicate that the acute changes in DNA methylation and mRNA expression of MRFs genes up to 8 hours may not be directly related to the interference effect (AU) | |
| FAPESP's process: | 17/01297-8 - Effects of concurrent training on the epigenetic mechanism of DNA methylation |
| Grantee: | Guilherme Defante Telles |
| Support Opportunities: | Scholarships in Brazil - Master |