Respostas Transcriptômicas Musculares Esqueléticas ao Treinamento Concorrente com Polifenóis no Envelhecimento Adultos: Um Ensaio Randomizado

O que aconteceu

Transcriptomic adaptations of ageing skeletal muscle to concurrent resistance training (RT) and high-intensity interval training (HIIT) remain insufficiently characterized. We investigated the effects of a 12-week concurrent RT + HIIT intervention on the vastus lateralis transcriptome in middle-aged and older adults and whether polyphenol supplementation modulated these responses. Thirty-eight adults (55-70 years; 17 polyphenol [PP], 21 placebo [PLA]) with paired skeletal muscle RNA-sequencing data participated in a randomized, double-blind trial. Participants completed a 30-day supplementation phase followed by a 12-week supervised RT + HIIT programme with continued supplementation. Muscle biopsies were obtained before (PRE) and after (POST) training. Differential expression analyses were adjusted for age, sex and muscle fibre type composition. Differential expression was assessed using FDR ≤ 0.05, with |log2FC| > 1 applied as an additional effect-size criterion.

Trecho mantido em inglês: a tradução automática não passou na conferência de números.

O que encontraram

Baseline transcriptomic differences between PP and PLA groups were minimal, with three FDR-significant transcripts, of which only HMOX1 additionally exceeded |log2FC| > 1 (FDR = 0.011; log2FC = 1.16). The group-by-time interaction analysis identified 14 FDR-significant transcripts, of which eight additionally exceeded |log2FC| > 1; these signals were characterized by low or sparse expression and high inter-individual variability, without a coherent supplementation-related transcriptional response. In the pooled paired PRE-POST analysis, 60 transcripts reached FDR significance, of which seven additionally exceeded |log2FC| > 1, including upregulation of CLLU1 (log2FC = 3.10; FDR = 0.0155), PRND (log2 log2FC = 2.60; FDR = 0.02) and LOX, and downregulation of MYH1 (log2FC = -1.3; FDR = 0.0001). Most FDR-significant transcripts showed relatively small estimated effect sizes, and functional enrichment analyses did not identify robust pathway-level adaptations.

Trecho mantido em inglês: a tradução automática não passou na conferência de números.

Por que isso importa

Em adultos de meia-idade e idosos, 12 semanas de RT + HIIT concomitantes induziram uma resposta transcricional muscular esquelética predominantemente de baixa magnitude. Mudanças selecionadas no nível de transcrição foram consistentes com processos relacionados à remodelação da matriz extracelular e regulação contrátil; no entanto, a ausência de níveis robustos de enriquecimento no nível de via limita as conclusões sobre adaptações coordenadas da via biológica. A suplementação de polifenol não influenciou significativamente a resposta transcricional ao treinamento físico.