Modulation of mRNA Expression of Biomarkers in the UPR-PERK Pathway by Ellagic Acid in Metabolic Dysfunction-Associated Fatty Liver Disease

Obesity contributes to an increase in the prevalence of metabolic dysfunction-associated fatty liver disease (MAFLD) and is diagnosed when hepatic steatosis is accompanied by at least one of the following factors: obesity or overweight, diabetes mellitus, or signs of metabolic abnormalities. MAFLD is a term that encompasses a wide range of liver disorders, ranging from simple steatosis to metabolic steatohepatitis, which can progress to cirrhosis and eventually, hepatocellular carcinoma (HCC). Lipotoxicity generated by a high-fat diet causes liver inflammation, therefore, blocking inflammatory pathways is considered a promising strategy to prevent MAFLD progression. Inflammatory responses and oxidative stress are linked to endoplasmic reticulum stress, thereby activating the unfolded protein response (UPR) pathway. Although drugs such as resmetirom and semaglutide have recently been approved for the treatment of MAFLD, there is still a need to identify complementary therapies with different mechanisms of action. In this context, the present study evaluated the hepatoprotective effect of ellagic acid through the modulation of mRNAs of proteins in the UPR-Perk pathway in a murine model fed a high-calorie diet. This study revealed that the high-calorie diet activated the UPR pathway in response to stress, increasing the expression of the Grp78, Eif2ak3, Eif2α, Ddit3, Atf4, and Nfe2l2 genes in the liver and epididymal adipose tissue. Ellagic acid modulated the pathway genes and reduced levels of glucose, total cholesterol, HDL and VLDL, triglycerides, insulin, and glycated hemoglobin, and could therefore be considered a hepatoprotective agent.