Dihydromyricetin: An Overview

Introduction

Dihydromyricetin (DMY or DHM) is an extract derived from a wild woody vine plant belonging to the Ampelopsis genus in the Vitaceae family. The primary active components of this extract are flavonoids, which are known for their numerous beneficial effects, including free radical scavenging, antioxidant properties, antithrombotic, anti-tumor, and anti-inflammatory activities. Dihydromyricetin is a unique type of flavonoid that, in addition to the general characteristics of flavonoids, possesses the ability to alleviate alcohol intoxication, prevent alcoholic liver disease and fatty liver, inhibit the deterioration of liver cells, and reduce the incidence of liver cancer. It is highly regarded for its hepatoprotective properties and effectiveness in mitigating alcohol-related damage.

Alternate Names and Primary Functions

Dihydromyricetin, also known as ampelopsin, ampelopsin A, myricetin, and Ampelopsis flavonoid, is one of the main active ingredients in vine tea and is recognized for its multiple biological functions.

Key Functions

1. Antioxidant and Free Radical Scavenging: Vine tea extract, which contains Dihydromyricetin, can effectively reduce lipid peroxidation levels in mice, preventing oxidative damage induced by free radicals and significantly enhancing the body's antioxidant capacity.

2. Antimicrobial Effects: The extract shows strong inhibitory effects on Staphylococcus aureus and Bacillus subtilis, as well as varying degrees of inhibition on Aspergillus flavus, Aspergillus niger, Penicillium, and Streptomyces. Dihydromyricetin specifically exhibits inhibitory effects on Staphylococcus aureus, drug-resistant Staphylococcus aureus, and Pseudomonas aeruginosa.

3. Liver Protection: Dihydromyricetin significantly inhibits the elevation of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, as well as reduces total bilirubin in the serum, demonstrating a marked effect in lowering enzyme levels and reducing jaundice. Additionally, vine tea extract can inhibit the formation of liver fibrosis in rats.

4. Lipid and Blood Sugar Regulation: Dihydromyricetin lowers blood lipid levels in mice, enhances antioxidant capacity, and reduces liver cell damage caused by high fat. It also has a noticeable hypoglycemic effect on hyperglycemic mice.

5. Anti-inflammatory and Analgesic Effects: The extract can significantly inhibit ear swelling in mice induced by xylene and suppress acetic acid-induced writhing response in mice.

6. Antitumor Effects: Vine tea extract has a significant inhibitory effect on the proliferation of certain cancer cells.

Dihydromyricetin as a Novel Anti-Alcohol Intoxication Medication

Research conducted by Shen et al. at the University of California, Los Angeles, has identified Dihydromyricetin as a promising therapeutic candidate for alcohol use disorders (AUDs). AUDs involve repeated alcohol use that leads to tolerance, withdrawal symptoms, and physical and psychological dependence. Currently, there are no effective treatments for AUDs without significant side effects.

Key Findings

· Dihydromyricetin was found to counteract acute alcohol intoxication and alleviate withdrawal symptoms in rats, including tolerance, increased anxiety, and seizure susceptibility.

· Dihydromyricetin significantly reduced alcohol consumption in an intermittent voluntary alcohol intake model in rats.

· GABAA receptors (GABAARs) are major targets of both acute and chronic alcohol effects on the brain. At the cellular level, Dihydromyricetin antagonized the effects of acute alcohol-induced potentiation of GABAARs and prevented alcohol exposure/withdrawal-induced GABAAR plasticity.

· The anti-alcohol effects of Dihydromyricetin on both behavior and central nervous system neurons were blocked by flumazenil, a benzodiazepine antagonist, suggesting that Dihydromyricetin's interaction with alcohol involves the benzodiazepine sites on GABAARs.

Conclusion

Dihydromyricetin has demonstrated pharmacological properties consistent with those expected to support the successful treatment of AUDs. Thus, Dihydromyricetin is a potential therapeutic candidate for addressing alcohol intoxication and dependence, making it a significant focus of ongoing research.