Immunomodulatory activity of the lignan 7-hydroxymatairesinol potassium acetate (HMR/lignan™) extracted from the heartwood of Norway spruce (Picea abies)

The pharmacological profile of the lignan 7-hydroxymatairesinol (HMR/lignan™, HMR) includes chemopreventive effects, antioxidant properties, and mild proestrogenic activity. The present study was devised to investigate the effects of HMR on THP-1 cells, an established model of human monocytes, and on human polymorphonuclear leukocytes (PMNs). In THP-1 cells, HMR concentration-dependently reduced LPS-stimulated tumor necrosis factor (TNF)-α secretion in the supernatant. HMR at low, sub-μM concentrations also reduced TNF-α mRNA, which was however enhanced by supra-μM concentrations of HMR. In human PMNs, HMR concentration-dependently reduced ROS production induced by either N-formyl-Met-Leu-Phe, phorbol myristate acetate or angiotensin II, as well as interleukin-8 production induced by either N-formyl-Met-Leu-Phe or angiotensin II. Results indicate that HMR is an effective inhibitor of both monocytic THP-1 cells and of human PMNs and warrant further studies to assess their relevance for the prevention and treatment of several conditions characterized by chronic systemic inflammation.