Administration of Protein Hydrolysates from Anchovy (Engraulis encrasicolus) Waste for Twelve Weeks Decreases Metabolic Dysfunction‐Associated Fatty Liver Disease Severity in ApoE–/–Mice

Metabolic dysfunction‐associated fatty liver disease (MAFLD) includes several diseases, ranging from simple steatosis to steatohepatitis, fibrosis and cirrhosis. Fish‐rich diets are considered helpful in the prevention of MAFLD, and the enzymatic hydrolysis of fish waste has been explored as a means of obtaining high‐value protein hydrolysates, which have been proven to exert beneficial bioactivities including anti‐obesity and hypocholesterol effects. This study aimed to assess the effect of the administration of protein hydrolysates from anchovy waste (APH) for 12 weeks on attenuated high‐fat diet‐induced MAFLD in apolipoprotein E‐knockout mice (ApoE–/–). Thirty ApoE–/– mice were divided into two groups (n = 15/group) and fed a high‐fat diet (HFD), with and without the addition of 10% (w/w) APH. After 12 weeks, serum and hepatic lipid profiles, hepatic enzyme activities, liver histology and immunohistochemistry were analyzed to assess hepatic steatosis, inflammation and fibrosis. Twelve‐weeks on a 10% (w/w) APH diet reduces total cholesterol and triglyceride serum levels, hepatic enzyme activity and hepatic triacylglycerol content (p < 0.0001), and results in a reduction in hepatic fat accumulation and macrophage recruitment (p < 0.0001). The results suggest that a 10% APH diet has an anti‐obesity effect, with an improvement in lipid metabolism, hepatic steatosis and liver injury as a result of a high‐fat diet. Protein hydrolysates from fish waste may represent an efficient nutritional strategy in several diseases, and their use as nutraceuticals is worthy of future investigation.