Study on the protective effect of active ingredients from goji berry sprouts and leaves on acute alcoholic liver injury
China is a big country of liver disease. With the widespread use of hepatitis B vaccine for newborns, viral liver disease is decreasing year by year, but with the change of people’s lifestyle, non viral liver disease is increasing year by year. Non viral liver diseases mainly include alcoholic liver disease (ALD), alcoholic fatty liver disease, non-alcoholic fatty liver disease, non-alcoholic liver disease, drug-induced liver disease, cirrhosis, and liver cancer, which seriously affect human health. ALD is the main representative of non viral liver disease and an important inducement of other liver diseases. Its incidence rate is increasing year by year and tends to be younger. The early stages of ALD are liver lesions caused by long-term heavy alcohol consumption, and its pathogenesis is complex and poorly studied. At present, there is a lack of effective drugs for the treatment of ALD, and there is an urgent need to develop new therapeutic drugs.

The Compendium of Materia Medica records that ‘picking goji berry leaves in spring is known as the Heavenly Essence Grass’. Tianjingcao has the effects of nourishing the liver, improving vision, and tonifying deficiency and nourishing essence. Goji berry is a traditional Chinese medicine that has the effect of protecting the liver and improving vision. Over the years, there have been many studies on goji berry fruit, but there are relatively few reports on the use of active ingredients from goji berry leaves for the treatment of ALD. This paper uses goji sprouts and leaves as raw materials to isolate and purify the active ingredients of goji sprouts and leaves (AILBL). The study found that the active ingredients mainly contain a group of antioxidant substances mainly composed of flavonoids. The pathogenesis of ALD is complex. Modern pathological research has found that the “second strike” theory refers to oxidative stress and inflammatory response, among which oxidative stress is a key factor in the occurrence and development of ALD. Therefore, the effective ingredients of goji berry leaves containing antioxidant active ingredients are natural medicinal resources for the development of clinical treatment of ALD. The aim of this study is to explore the protective effects and possible antioxidant mechanisms of active ingredients from goji berry sprouts and leaves on acute alcoholic liver injury in mice, providing a theoretical basis for the development of functional food additives or health products with the ability to prevent and treat alcoholic liver injury in the future.

Firstly, ABTS and DPPH methods were used to detect the antioxidant activity of AILBL; Next, 48 male ICR mice were randomly divided into six groups: normal control group, alcohol model group, positive drug control group, silymarin (200 mg/kg, i.g.), and AILBL low, medium, and high dose groups (30, 100, 300 mg/kg). They were orally administered once a day for one week. After the last administration for 12 hours, a mouse model of acute alcoholic liver injury was established by gavage with 6 g/kg alcohol at 12 hour intervals for a total of 3 times. Detect and analyze the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) in mouse serum, and malondialdehyde (MDA) and reduced glutathione (GSH) in liver tissue. Using hematoxylin eosin (H&E) and immunohistochemical staining to observe the pathological changes and oxidative stress-related proteins in liver tissue.

Goji berry is one of the classic traditional Chinese medicines, often appearing in the Book of Songs, Shennong Bencao Jing, and medicinal theory. Research has shown that goji berries have various pharmacological effects such as moistening the lungs, nourishing qi, protecting the liver and improving vision. People’s research focuses more on goji berries, while there is relatively less research on goji sprouts and leaves. Goji berries are rich in antioxidants such as goji polysaccharides and flavonoids, which can enhance the body’s learning and memory ability, anti fatigue ability, and immunity. They can also effectively eliminate free radicals, improve intracellular antioxidant enzyme activity, protect organs such as the liver and kidneys, and provide physiological and biochemical protection to the body. Compared to goji berries, our research has found that the content of flavonoids in goji berry leaves is higher, and it has a significant ability to scavenge free radicals in vitro, which has a good preventive and therapeutic effect on ALD experimental animal models. In the future, it can be developed into drugs or health products for the prevention and treatment of ALD.
Alcohol is a small molecule organic compound with high permeability, which is easily absorbed by cells and induces the production of large amounts of free radicals, causing oxidative stress damage to cells. The liver is the main organ for alcohol metabolism and an important target organ for alcohol induced injury. Alcohol and its metabolite acetaldehyde have toxic effects on the liver. Alcohol can upregulate the levels of genes related to lipid synthesis and downregulate the levels of genes related to fatty acid oxidation, accelerating the synthesis of fatty acids. However, lipids such as triglycerides and free fatty acids cannot be metabolized in a timely manner, resulting in deposition in the liver; Acetaldehyde can promote the activation of stellate cells, affect the production of ATP by mitochondria, and affect the normal synthesis and secretion of proteins, leading to obstacles in the secretion of fat and proteins, causing the deposition of extracellular matrix in the liver, resulting in fatty lesions, necrosis, and fibrosis of liver cells, and further developing into more severe hepatitis, cirrhosis, and liver cancer. Secondly, alcohol is metabolized through various pathways to produce a large amount of oxidative stress products, such as OH -, O2- ·, H2O2 and other free radicals, which disrupt the redox balance in liver cells, promote oxidative stress response, damage the normal function of mitochondria, deplete glutathione in mitochondria, reduce the self antioxidant protection ability of liver cells, and lead to the continuous accumulation of peroxides in liver cells, exacerbating liver damage. Oxidative stress is an important factor in the pathogenesis of ALD.

About 20% of people experience liver damage after excessive or long-term alcohol consumption, and the excessive production of reactive oxygen species and lipid metabolism disorders during alcohol metabolism are important factors that induce cell damage and apoptosis. When liver cells and mitochondria are attacked by reactive oxygen species, reducing macromolecules such as GSH in the cells rapidly decrease, DNA breaks, mitochondria and cell membranes are damaged, and ALT and AST are released into the bloodstream. Therefore, serum ALT and AST levels are commonly used to evaluate liver damage and liver function. This experiment established an acute alcoholic liver injury model through three consecutive rounds of alcohol gavage. The study found that the serum ALT and AST levels of the model group mice given alcohol gavage alone exceeded normal levels, while the ALT and AST levels in the serum of the mice given positive drug and different concentrations of AILBL for prevention and treatment significantly decreased. The pathological morphology of the liver tissue of the mice in the treatment group was well improved, and the expression of the oxidative stress key protein CYP2E1 was reduced, indicating that AILBL has a good protective effect on acute alcoholic liver injury.

AILBL is rich in various antioxidant substances such as flavonoids, which are important material basis for its antioxidant properties and protection against cellular oxidative damage. This study found that AILBL can significantly reduce MDA levels, promote GSH regeneration, enhance liver free radical scavenging ability in mice with acute alcoholic liver injury, thereby reducing the “secondary strike” damage to the liver caused by the accumulation of peroxidation products in the body, and has significant liver protective functions. Meanwhile, AILBL significantly reduced ethanol induced ROS accumulation in vitro by inhibiting CYP2E1 expression.

In summary, our laboratory found that AILBL can clear MDA in liver cells, increase GSH levels, inhibit CYP2E1 expression in liver cells, and improve alcohol induced oxidative stress, lipid peroxidation, and inflammation in liver cells by extracting effective ingredients from goji sprouts and leaves and studying their protective effects against acute alcoholic liver injury. This study will make the active ingredients of goji berry leaves effective drugs or health supplements for the prevention and treatment of liver diseases such as ALD, and make new contributions to the modernization of traditional Chinese medicine research in China.