Abstract
This study aimed to evaluate the modulatory effect of dietary taurine supplementation on protein turnover of meagre juveniles fed semi-purified plant-based diets. For that purpose, fish (3.2 ± 0.2 g) were fed with five isoproteic (61.2%), isolipidic (16.6%) and isoenergetic (21.9 kJ g−1) experimental diets supplemented with 0.5% (Tau0.5), 1% (Tau1), 1.5% (Tau1.5) and 2% (Tau2) taurine or not (Tau0) for 38 days. The resulting growth parameters, protein expression levels and the activity of several proteolytic markers involved in the two major degradation pathways in vertebrates (autophagy-lysosomal and ubiquitin-proteasome) were assessed in the liver, intestine and white muscle of meagre. Increasing dietary taurine concentrations promoted fish growth, feed utilization and whole-body protein, lipid and energy contents. Dietary taurine seemed to modulate the activity of cathepsins D and B in white muscle and cathepsin L in the liver. Although, no significant effects were observed on proteasome activity, 1% dietary taurine supplementation decreased the expression of the Psmb4 proteasome subunit in the liver of fish when compared to lower taurine concentrations. No taurine effects were detected on the proteolytic markers analysed in the intestine of meagre. Hsp70 expression levels were also not affected by any of the experimental dietary taurine concentrations. Overall, experimental diet Tau2 promoted the highest growth rate which can be explained by a significant decrease in protein degradation in the liver and white muscle preferentially via the autophagy-lysosomal pathway (cathepsins) over the ubiquitin-proteasome route.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.