Glycyrrhizin health benefit, safety, caution, toxicity, adverse events and concerns

Glycyrrhizin has been used to treat chronic hepatitis in Japan and Europe. It is thought to induce pseudoaldosteronism via inhibition of type 2 11beta-hydroxysteroid dehydrogenase (11beta-HSD2) by glycyrrhetinic acid, a major metabolite of glycyrrhizin.

Glycyrrhizin protects brain cells
Glycyrrhizin Prevents 7-Ketocholesterol Toxicity Against Differentiated PC12 Cells by Suppressing Mitochondrial Membrane Permeability Change.
Neurochem Res. 2009. Department of Neurology, Seoul Veterans Hospital, Seoul, South Korea.
Defects in mitochondrial function participate in the induction of neuronal cell injury. In neurodegenerative conditions, oxidative products of cholesterol are elevated and oxysterols seem to be implicated in neuronal cell death. The present work was designed to study the inhibitory effect of licorice compounds glycyrrhizin and 18beta-glycyrrhetinic acid against the toxicity of 7-ketocholesterol in relation to the mitochondria-mediated cell death process. 7-Ketocholesterol induced the nuclear damage, loss of the mitochondrial transmembrane potential. Glycyrrhizin and 18beta-glycyrrhetinic acid prevented the 7-ketocholesterol-induced mitochondrial damage, leading to caspase-3 activation and cell death. The results obtained show that glycyrrhizin and 18beta-glycyrrhetinic acid may prevent the 7-ketocholesterol-induced neuronal cell damage by suppressing changes in the mitochondrial membrane permeability.

Glycyrrhizin protects liver cells
Protective effect of glycyrrhizin, glycyrrhetic acid and matrine on acute cholestasis induced by alpha-naphthyl isothiocyanate in rats.
Planta Med. 2007. Center of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing, Jiangsu, P. R. China.
Alpha-naphthyl isothiocyanate (ANIT) is a known hepatotoxicant that causes acute cholestatic hepatitis characterized by the infiltration of neutrophils around bile ducts and necrotic hepatocytes. The effects of glycyrrhizin, 18beta-glycyrrhetinic acid, matrine, oxymatrine (OMT), salvianolic acid B (SAB), silymarin (SI) and dexamethasone (DEX) on ANIT-induced acute cholestasis in rats were investigated. The protective effect of dexamethosone is directed toward cholangiocytes rather than hepatocytes whereas the natural products, glycyrrhetinic acid, glycyrrhizin and matrine exhibit significantly better protective effects against ANIT-induced liver damage including the protection of hepatocytes as well as cholangiocytes.

Glycyrrhizin influences methotrexate levels in the blood
Glycyrrhizin and Licorice Significantly Affect the Pharmacokinetics of Methotrexate in Rats.
J Agric Food Chem. 2009. Graduate Institute of Pharmaceutical Chemistry, School of Pharmacy, China Medical University, Taichung, Taiwan.
Glycyrrhizin and licorice (root of Glycyrrhiza uralensis) are worldwide food additives and important oriental phytomedicines. This study investigated the biological fate of Glycyrrhizin by orally giving glycyrrhizin and licorice decoction to rats. The concurrent use of glycyrrhizin or licorice with methotrexate should be with a good deal of caution.