Dietary vitamin K 3 activates mitophagy, improves antioxidant capacity, immunity and affects glucose metabolism in Litopenaeus vannamei .

An 8-week feeding experiment was conducted to appraise the influence of dietary vitamin K 3 on the growth performance, antioxidant capacities, immune responses, mitophagy and glucose metabolism in Litopenaeus vannamei . Six diets containing graded dietary vitamin K 3 (0.40(control), 9.97, 20.29, 39.06, 79.81 and 156.02 mg kg -1 of vitamin K 3 , respectively) levels were formulated. A total of 900 shrimp with 0.90 g initial weight were randomly assigned to six diets with three replications. Our results revealed that diets supplemented with 9.97-156.02 mg kg -1 vitamin K 3 didn't affect the growth performance in L. vannamei . In general, compared with the control group, 39.06 mg kg -1 vitamin K 3 group significantly increased ( P < 0.05) the total antioxidative capacity, and the activities of catalase, glutathione, nitric oxide synthase, alkaline phosphatase and acid phosphatase in serum and hepatopancreas. 39.06 mg kg -1 vitamin K 3 group significantly decreased ( P < 0.05) the malondialdehyde in serum and hepatopancreas. The mRNA levels of antioxidant and immune related genes were increased synchronously ( P < 0.05). In addition, 39.06 mg kg -1 vitamin K 3 group increased glycogen content and levels of mitophagy ( pink1 , ampkα , parkin , lc3 , atg13 , atg12 ) genes. Expression levels of glucose transport related gene ( glut1 ), glycolysis related genes ( hk , pfk ), glycogen synthesis related genes ( gsk-3β , gys ), insulin-like peptides (ILPs)/AKT/PI3K pathway related genes ( insr , irsl , akt , pi3k , pdpk1 ) were increased in the hepatopancreas of 39.06 mg kg -1 vitamin K 3 group. In conclusion, the present results indicated that although dietary supplementing vitamin K 3 had no influence on the growth performance, 39.06 mg kg -1 vitamin K 3 could activate ampkα / pink1 / parkin mediated mitophagy, improve antioxidant capacity and immune response. Moreover, vitamin K 3 could trigger ILPs/AKT/PI3K signaling pathways and influence glucose metabolism in L. vannamei . This finding would help to advance the field of vitamin K 3 nutrition and guide the development of future crustacean feeds.