Antioxidant effects of the aqueous extract of turmeric against hydrogen peroxide-induced oxidative stress in spotted seabass (Lateolabrax maculatus)

Abstract

Intensive aquaculture-induced oxidative stress is detrimental to fish health and yield. Medicinal plants show promise as natural health boosters and antioxidants in the aquaculture industry. Therefore, this work investigated the effects of turmeric aqueous extract (TAE) on the growth performance, antioxidant status, and hydrogen peroxide (H2O2)-induced oxidative stress in spotted seabass (Lateolabrax maculatus). Fish were fed diets supplemented with 0 (Con), 2 (TAE2), or 4 (TAE4) g/kg TAE for eight weeks, then were injected with H2O2. The results showed that dietary supplementation of TAE did not affect fish growth, feed utilization, or body composition. TAE treatment increased liver antioxidant enzyme activities and decreased liver malondialdehyde content and serum levels of glutamate oxalate transaminase, glutamate pyruvate transaminase, and lactate dehydrogenase. Furthermore, the increases in mortality, liver malondialdehyde content, and serum biomarkers of liver injury in the H2O2-treated fish were inhibited as a consequence of the TAE treatment. In addition, TAE treatment activated the Nrf2/Keap1 pathway in the liver, supported by the up-regulated expression of nrf2, ho-1, and gclc, and down-regulated keap1 expression. Overall, dietary incorporation of TAE protected against H2O2-induced oxidative stress in spotted seabass probably by enhancing antioxidant capacity through the Nrf2/Keap1 pathway.