Schisandrins are lignans found in the fruit of Schisandra chinensis ("Wu Wei Zi"), a traditional Chinese medicinal plant. Historically, Schisandra has been used in traditional Chinese medicine (TCM) to promote liver health and treat hepatitis. However, in recent decades, scientific interest has focused on the bioactive components—primarily schisandrin, schisandrin A, B, and C—which have demonstrated hepatoprotective effects in laboratory and animal studies.

Experimental research indicates that schisandrins possess antioxidant, anti-inflammatory, and anti-fibrotic properties. These compounds have been shown to protect hepatocytes from damage induced by toxins, viruses, and oxidative stress. For example, studies in mice and rats with chemically-induced liver injury (such as by carbon tetrachloride or alcohol) found that schisandrin B reduced liver enzyme levels, lipid peroxidation, and inflammatory markers. In vitro studies suggest schisandrins may also inhibit hepatitis virus replication and modulate immune responses.

Despite these promising preclinical results, robust human clinical trials are limited. Some small clinical studies from China have reported improvements in liver function markers in hepatitis patients receiving Schisandra extracts, but these studies often lack rigorous controls or adequate sample sizes. As a result, while there is scientific support—mainly from animal and in vitro studies—for the hepatoprotective effects of schisandrins, high-quality clinical evidence is still pending.