Dietary sanguinarine supplementation recovers the decrease in muscle quality and nutrient composition induced by high-fat diets of grass carp (Ctenopharyngodon idella)

The intake of high-fat diets (HFD) has been shown to diminish the muscle quality of aquatic animals. Sanguinarine, as an excellent additive, exhibits the capability to reduce fat deposition and alleviate inflammation. However, its role in the muscle quality reduction caused by HFD remains unclear. An eight-week trial was conducted to investigate the impacts of dietary supplementation of sanguinarine at 1200 μg/kg (HFDS; crude fat = 10%) on the muscle quality of grass carp (Ctenopharyngodon idellus) in comparison to a basic diet (CON, crude fat = 5%). Each group had 3 replicates, with 40 fish per replicate. This experiment employed one-way ANOVA and Duncan's multiple comparisons of the means. The results showed that the HFD exhibited lower growth performance, reduced protein deposition, myofiber diameter, and muscle hardness, coupled with higher levels of fat deposition and inflammation when compared with the CON. However, HFDS improved growth performance, fat metabolism (ppar-α, lpl, atgl, and cpt1 expression exhibited a significant elevation), protein deposition (the protein and mRNA levels of AKT, PI3K, TOR, and S6K demonstrated a marked increase), myofiber diameter, muscle hardness, and the total content of eicosapentaenoic acid and docosahexaenoic acid. Furthermore, the HFDS reduced oxidative damage caused by fat deposition by significantly downregulating nf-κb, il-1β, il-6, il-8, and tnf-α expression and markedly upregulated nrf2, gpx4, cat, sod, and gr expression. The findings from this study suggest that sanguinarine has the potential to alleviate the adverse effects of HFD on growth and muscle quality, providing a theoretical foundation for its practical implementation.