## 1 Introduction  
The liver is a vital organ in the human body responsible for detoxification and metabolism. Alcohol abuse damages the liver, and the metabolic disorders caused by ethanol and its metabolites lead to alcoholic liver disease (ALD), including steatosis, hepatitis, fibrosis, and cirrhosis [1]. The pathogenesis of ALD is associated with oxidative stress (OS), lipid peroxidation, and inflammatory cytokine production caused by ethanol and its metabolites [2]. The liver metabolites ethanol via three enzymatic pathways: alcohol dehydrogenase, cytochrome p450 (also known as the microsomal ethanol oxidizing system [MEOS]), and catalase (CAT) [3]. Alcohol abuse activates the cytochrome P450 family 2 (CYP2E1) in the MEOS, leading to the production and accumulation of reactive oxygen species (ROS) in the hepatocytes [4]. Excess ROS causes OS and lipid peroxidation, which induces hepatocyte steatosis and disrupts membrane permeability [5]. Exposure of hepatocytes to OS and lipid peroxidation causes hepatic inflammation, fatty liver, and fibrosis [6; 7; 8].  
There is growing interest in identifying natural compounds that can protect the liver from ethanol-induced damage. Apples are readily available and contain various beneficial compounds, including sugars, organic acids, and polyphenols [9]. Apples improve overall health, and their wide range of pharmacological properties is indicated by the ancient proverb, \"An apple a day keeps the doctor away\" [10]. Apples have antioxidant and antimicrobial properties and regulate cholesterol metabolism [11; 12]. Given the safety and accessibility of natural food products, the development of dietary therapies has attracted widespread interest in recent years, and many natural foods are alternatives to pharmacological therapies [13; 14; 15]. Components such as quercetin and phloretin in apples have hepatoprotective effects that can counteract the damaging effects of alcohol on the liver. Previous studies have shown that quercetin has potent antioxidant and anti-inflammatory properties, which may help protect the liver against OS and inflammation induced by alcohol consumption [16; 17; 18]. However, the effects of apple consumption on ALD are unknown.  
The significance of this study lies in the potential for apple consumption to provide a simple and natural solution for protecting against liver injury caused by alcohol consumption. Apples have high antioxidant activity, which is a rich source of quercetin, and improve lipid metabolism [11; 12], indicating the potential of apples in improving ALD. This study assessed the hepatoprotective effects of apples against acute alcohol-induced liver injury in rats by performing enzyme activity assays, a real-time polymerase chain reaction, and an enzyme-linked immunosorbent assay. While further research is needed to determine whether the protective effects seen in rats can be replicated in humans, given the significant health risks associated with alcohol consumption, finding simple and accessible ways to protect against its harmful effects is of great importance. If further research confirms these findings, the consumption of apples may provide a safe and natural way to protect against liver injury caused by alcohol consumption.