Methanolic Alnus glutinosa bark extract affect ROS and TNF-α production

Alnus glutinosa (L.) Gaertn., commonly known as 'European alder', presents several types of secondary plant metabolites, including anthraquinones, phenolic glycosides, flavonol glycosides, terpenoids or xanthones, that had been previously reported in barks, buds, leaves and pollens.

Alnus glutinosa stem bark (AGSB) is traditionally used as alterative, astringent, cathartic, febrifuge, emetic (fresh), haemostatic and tonic. In addition, a decoction of AGSB is used to treat swelling, inflammation and rheumatism. These traditional uses suggest that AGSB may contain active metabolites related to the inflammation process.

Inflammation is associated with the progression of numerous diseases and is accompained by the chronic release of cytokines and reactive oxygen species (ROS), which may be involved in tissue injury increment. Moreover, ROS, as well, contribute to the expression of a variety of different inflammatory cytokines such as TNF-α, which is considered to be a primary mediator of the inflammatory response. In this sense, the present study was designed to evaluate the capacity of the AGBS extract to reduce ROS generation in H2O2-induced oxidative stress in HeLa cells. In addition, the extract effect on TNF-α production using HL60 cell line, was also tested.

Results show that the AGSB extract is able to protect cells from induced oxidative stress and may be able to decrease TNF-α production. These biological properties are linked to a successful reduction in inflammatory processes and may support, in part, its ethnopharmacological use.

Keywords: Alnus glutinosa. TNF-α. ROS