Impacts of a polyphenol mixture on skeletal muscles in growing rats
Year: 2025
Type: conference-paper
Abstract: Background: Skeletal muscle atrophy occurs in various pathophysiological conditions, such as aging, sedentary lifestyles, and chronic inflammatory diseases. The usual recommendations to combat this atrophy include adequate protein intake combined with regular physical exercise. However, providing regular exercise at healthy levels is not always feasible for certain vulnerable populations. An alternative approach focuses on the polyphenols provided by plant-based food sources. Indeed, the consumption of flavonoids, in particular, appears to offer benefits for muscle quality due to their antioxidant and anti-inflammatory actions, which enhance muscle performance. Some studies highlight the ability of polyphenols to reduce muscle damage induced by intense exercise. However, the impact of chronic polyphenol consumption on healthy muscle has never been studied. Method: Sprague-Dawley male rats were fed a standard diet (SD) and a standard diet supplemented with a 0.3% w/w polyphenol mixture (PP), mimicking the daily polyphenol intake (both qualitatively and quantitatively) for 6 weeks. Food intake, body weight, and body composition were monitored weekly throughout the intervention. At the end of the intervention, the EDL, gastrocnemius, tibialis and soleus muscles were collected and weighed. The EDL and soleus muscles were fixed in PFA for histology, frozen in isopentane/nitrogen for immunofluorescence staining, and directly frozen in nitrogen for gene expression assays. Results: Dietary intervention did not modify daily intake, weight gain, or body composition (fat mass vs. lean mass). The mean polyphenol intake was 158 ± 10 mg/day/kg. The muscle mass/body weight ratio was not affected by polyphenol supplementation. Immunostaining against BAF8 (marker of type I fibers), SC71 (type IIa fibers), and BAF3 (type IIb fibers) on cryosections of EDL and soleus is ongoing. This will allow the evaluation of the proportion and mean area of type I versus type II fibers. Fiber composition will be completed by the analysis of the expression of key muscular markers. Conclusion: This study will describe for the first time the effects of a complex polyphenol supplementation on the structure of growing skeletal muscle, thereby enhancing our understanding of the biological effects of polyphenols.
Source: HAL
Language: English
Subfield: Physiology (medical)
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W7205094396