Autophagy‐related gene regulation in liver and muscle of rainbow trout ( Oncorhynchus mykiss ) upon exposure to chloroquine, deoxynivalenol and nutrient restriction

Abstract

Autophagy is important for maintaining homeostasis, nutrient availability and muscle mass in fish. The effect of chloroquine (CQ) and deoxynivalenol (DON) on autophagy-related gene (Atg) regulation was examined in rainbow trout fed with either CQ or DON and compared with pair-fed (nutrient restriction [NR]) and optimally-fed group. Rainbow trout were divided into four groups and, respectively, fed optimal diet (control), diet-containing CQ (6 mg/g), diet-containing DON (0.005 mg/g) or pair-fed the control diet. On days 0, 1, 3, 7, 14 and 21, liver and muscle were sampled to evaluate the expression of atg4, atg5, atg7, atg12, atg13, atg16, bec-1, gabarap and lc3. In both liver and muscle, CQ induced the highest number of Atgs, with eight in liver and seven in muscle; DON-induced six Atgs in liver and three in muscle; and pair-fed induced three Atgs in liver and two in muscle. In vitro, the effect of NR and CQ on Atg was examined in the RTL-W1 cell line. NR induced all Atg in RTL-W1, with the exception of bec-1. Furthermore, NR combined with CQ enhanced Atg expression greater than NR alone. Overall, CQ and DON can modulate Atg in rainbow trout, which can influence physiology and growth in aquaculture.