Pinoresinol is a common component of the lignan fraction found in olive oil, in Styrax sp. and in Forsythia suspense and in other plants. Many experimental studies have been focused on the strong antioxidant activity of pinoresinol. Enzymatic hydrolysis of maltose is inhibited by (+)-pinoresinol through competitive and noncompetitive manners. Pinoresinol caused an upregulation of the CDK inhibitor p21(WAF1/Cip1) both at mRNA and protein levels so suggesting that this could be a mechanism by which pinoresinol reduced proliferation and induced differentiation on HL60 leukemia cells. Pinoresinol may have a therapeutic potential to prevent breast cancer development via the reduction of intracellular oxidative stress and DNA damage in human mammary epithelial cells. In vivo, pinoresinol ameliorates CCl4-induced acute liver injury, and this protection is likely due to anti-oxidative activity and down-regulation of inflammatory mediators through inhibition of NF-kappaB and AP-1.