Anti-inflammatory effects of thymoquinone in activated BV-2 microglial cells

Abstract

Thymoquinone (TQ), the main pharmacological active ingredient within the black cumin seed (Nigella sativa) is believed to be responsible for therapeutic effects on chronic inflammatory conditions such as arthritis, asthma and neurodegeneration. In this study, we evaluated the potential anti-inflammatory role of TQ in lipopolysaccharide (LPS)-stimulated BV-2 murine microglia cells. The results obtained indicated that TQ was effective in reducing NO2- with an IC50 of 5.04 μM, relative to selective iNOS inhibitor LNIL- L-N6-(1-Iminoethyl)lysine (IC50 4.09 μM). TQ mediated reduction in NO2- was found to parallel the decline of iNOS protein expression as confirmed by immunocytochemistry. In the next study, we evaluated the anti-inflammatory effects of TQ on ninety – six (96) cytokines using a RayBio AAM-CYT-3 and 4 cytokine antibody protein array. Data obtained establish a baseline protein expression profile characteristic of resting BV-2 cells in the order of osteopontin > MIP-1alpha > MIP-1g > IGF-1 and MCP-I. In the presence of LPS [1ug/ml], activated BV-2 cells produced a sharp rise in specific pro-inflammatory cytokines/chemokine’s IL-6, IL-12p40/70, CCL12 /MCP-5, CCL2 / MCP-1, and G-CSF which were attenuated by the addition of TQ (10μM). The TQ mediated attenuation of MCP-5, MCP-1 and IL-6 protein in supernatants from activated BV-2 cells were corroborated by independent ELISA and mRNA expression profiling using RT2 Profiler PCR cytokine arrays. Moreover, the data obtained from the RT2 PCR demonstrated a similar pattern where the LPS mediated elevation of mRNA for IL-6, CCL12 /MCP-5, CCL2 / MCP-1 were significantly attenuated by TQ (10μM). Also, in this study, consistent data were obtained for both protein antibody array densitometry and ELISA assays. In addition, TQ was found to reduce LPS mediated elevation in gene expression of Cxcl10 and a number of other cytokines in the panel. These findings demonstrate the significant anti-inflammatory properties of TQ in LPS activated microglial cells. Therefore, the obtained results might indicate the usefulness of TQ in delaying the onset of inflammation-mediated neurodegenerative disorders involving activated microglia cells.

Thymoquinone increases the expression of neuroprotective proteins while decreasing the expression of pro-inflammatory cytokines and the gene expression NFκB pathway signaling targets in LPS/IFNγ -activated BV-2 microglia cells

“…Previously our lab has demonstrated the anti-inflammatory properties of TQ in BV-2 microglia solely activated with LPS (Taka et al, 2015). However, in this study we co-activated the BV-2 microglial cells with LPS and INFγ because the two pro-inflammatory agents work synergistically to induce maximal transcriptional responses, enhancing the release of NO in microglia upon activation (Paludan, 2000, Pawate et al, 2004, Yoo et al, 2008).…”

“…Studies have shown that TQ is a ROS scavenger (Mansour et al, 2002; Badary et al, 2003) capable of reducing the levels of several ROS and lipid/protein oxidation markers in liver and kidney tissue, microglia and macrophages (El-Mahmoudy et al, 2002; Attia et al, 2010; Mahmoud et al, 2014; Cobourne-Duval et al, 2016). Likewise, the anti-inflammatory properties of TQ treatment have been demonstrated in mast cells, microglia, kidney, and liver (El Gazzar et al, 2007; Al-Malki and Sayed, 2014; Mahmoud et al, 2014; Taka et al, 2015). Furthermore, studies have also indicated that TQ treatment provides neuroprotection against amyloid β-induced and α-synuclein-induced neurotoxicity (Khan et al, 2012, Alhebshi et al, 2013, Alhebshi et al, 2014), traumatic brain injury (Gülşen et al, 2016), environmental neurotoxins (Kanter, 2008; Radad et al, 2009; Radad et al, 2014), and transient forebrain ischemia (Al-Majed et al, 2006).…”

Olanzapine-induced renal damage and metabolic side effects: the protective effect of thymoquinone

“…TQ is a principal active ingredient of the Nigella sativa seeds (5). It has been informed to exhibit various pharmacological activities, such as antihypertensive (6), anti-inflammatory and anti-cancer (7,8), antidiabetic (9) and analgesic properties (10). TQ is also reported to possess strong antioxidant properties.…”

The attenuating effects of plumbagin on pro-inflammatory cytokine expression in LPS-activated BV-2 microglial cells

“…Based on a previously conducted optimization study in our lab, 1 μg/mL of LPS was found to be the optimum concentration for BV-2 microglial cells activation. (Taka et al, 2015). Others also indicated similar LPS dose (Pinho et al, 2011).…”