title: Shikonin Isolated from Lithospermum erythrorhizon Downregulates Proinflammatory Mediators in Lipopolysaccharide-Stimulated BV2 Microglial Cells by Suppressing Crosstalk between Reactive Oxygen Species and NF-κB.
abstract: According to the expansion of lifespan, neuronal disorder based on inflammation has been social problem. Therefore, we isolated shikonin from Lithospermum erythrorhizon and evaluated anti-inflammatory effects of shikonin in lipopolysaccharide (LSP)-stimulated BV2 microglial cells. Shikonin dose-dependently inhibits the expression of the proinflammatory mediators, nitric oxide (NO), prostaglandin E2 (PGE2), and tumor necrosis factor-α (TNF-α) as well as their main regulatory genes and products such as inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and TNF-α in LPS-stimulated BV2 microglial cells. Additionally, shikonin suppressed the LPS-induced DNA-binding activity of nuclear factor-κB (NF-κB) to regulate the key regulatory genes of the proinflammatory mediators, such as iNOS, COX-2, and TNF-α, accompanied with downregulation of reactive oxygen species (ROS) generation. The results indicate that shikonin may downregulate the expression of proinflammatory genes involved in the synthesis of NO, PGE2, and TNF-α in LPS-treated BV2 microglial cells by suppressing ROS and NF-κB. Taken together, our results revealed that shikonin exerts downregulation of proinflammatory mediators by interference the ROS and NF-κB signaling pathway.
authors.affiliation: Department of Marine Life Sciences, Jeju National University, Jeju 690-756, Republic of Korea.
authors.forename: Rajapaksha Gedara
authors.initials: RG
authors.lastname: Prasad
authors.affiliation: Department of Biochemistry, College of Oriental Medicine, Dongeui University, Busan 614-051, Republic of Korea.
authors.forename: Yung Hyun
authors.initials: YH
authors.lastname: Choi
authors.affiliation: Department of Marine Life Sciences, Jeju National University, Jeju 690-756, Republic of Korea.
authors.forename: Gi-Young
authors.initials: GY
authors.lastname: Kim
keywords: Nuclear factor-κB; Proinflammatory mediators; Reactive oxygen species; Shikonin