Anti-Neuroinflammatory Effects of Arecae pericarpium on LPS-Stimulated BV2 Cells

Abstract

Arecae pericarpium (AP), the fruit peel of the betel palm, is a traditional Oriental herbal medicine. AP is used to treat various diseases and conditions, such as ascites, edema, and urinary retention, in traditional Korean medicine. Recent studies have demonstrated its anti-obesity and antibacterial effects; however, its anti-neuroinflammatory effects have not yet been reported. Therefore, we investigated the anti-neuroinflammatory effects of AP on lipopolysaccharide (LPS)-stimulated mouse microglia in this study. To determine the anti-neuroinflammatory effects of AP on BV2 microglial cells, we examined the production of nitric oxide (NO) using Griess assay and assessed the mRNA expression levels of inflammatory mediators, such as inducible NO synthase (iNOS) and cyclooxygenase (COX)-2, and pro-inflammatory cytokines, such as interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α, using a real-time reverse transcription-polymerase chain reaction. Furthermore, we determined the levels of mitogen-activated protein kinases and IκBα via Western blotting to understand the regulating mechanisms of AP. AP treatment decreased NO production in LPS-stimulated BV2 cells. Additionally, AP suppressed the expression of iNOS and COX-2 and the production of pro-inflammatory cytokines. AP also inhibited the activation of p38 and nuclear factor-kappa B (NF-κB) in LPS-stimulated BV2 cells. Therefore, AP exerts anti-neuroinflammatory effects via inactivation of the p38 and NF-κB pathways.

In Vitro and In Vivo Anti-Inflammatory and Antidepressant-like Effects of Cannabis sativa L. Extracts

“…Animals that did not receive drugs were injected with the corresponding vehicle (control group). In vitro, LPS (1 µg/mL) was treated for 24 h in nitrite oxide concentration experiments and for 6 h in RT-PCR experiments [ 63 ].…”

“…The cells were cultured in the Roswell Park Memorial Institute-1640 medium (Gibco, Billings, MT, USA), supplemented with 10% fetal bovine serum (Gibco, USA) and 1% penicillin/streptomycin (100 U/mL, Gibco, USA), and incubated at 37 °C and 5% CO 2 . Cells were grown to 70–80% confluency and used in the experiments [ 63 ].…”

“…In order to extract total RNA, BV2 microglial cells were seeded at a density of 1 × cells/well in a 6-well plate [ 63 , 69 ]. Cannabis sativa L. extracts (200, 400, 800, and 1600 µg/mL) were pretreated for 1 h and co-treated with LPS (1 µg/mL) for 6 h. Then, the supernatant was removed, and the cells were lysed using the Easy-Blue RNA extraction kit (iNTRON Biotechnology, Sungnam, Republic of Korea).…”