Dietary vitamin K3 activates mitophagy, improves antioxidant capacity, immunity and affects glucose metabolism in Litopenaeus vannamei

Abstract

An 8-week feeding experiment was conducted to appraise the influence of dietary vitamin K₃ on the growth performance, antioxidant capacities, immune responses, mitophagy and glucose metabolism in Litopenaeus vannamei. Six diets containing graded dietary vitamin K₃ (0.40(control), 9.97, 20.29, 39.06, 79.81 and 156.02 mg kg^-1 of vitamin K₃, 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 K₃ didn't affect the growth performance in L. vannamei. In general, compared with the control group, 39.06 mg kg^-1 vitamin K₃ 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 K₃ 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 K₃ 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 K₃ group. In conclusion, the present results indicated that although dietary supplementing vitamin K₃ had no influence on the growth performance, 39.06 mg kg^-1 vitamin K₃ could activate ampkα/pink1/parkin mediated mitophagy, improve antioxidant capacity and immune response. Moreover, vitamin K₃ could trigger ILPs/AKT/PI3K signaling pathways and influence glucose metabolism in L. vannamei. This finding would help to advance the field of vitamin K₃ nutrition and guide the development of future crustacean feeds.