Next Article in Journal
Behavioral, Physiological, Demographic and Ecological Impacts of Hematophagous and Endoparasitic Insects on an Arctic Ungulate
Previous Article in Journal
FDA Approvals and Consensus Guidelines for Botulinum Toxins in the Treatment of Dystonia
Open AccessArticle

Classical and Alternative Activation of Rat Microglia Treated with Ultrapure Porphyromonas gingivalis Lipopolysaccharide In Vitro

1
Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL 60515, USA
2
Biomedical Sciences Program, College of Graduate Studies, Midwestern University, Downer Grove, IL 60515, USA
3
College of Dental Medicine Illinois, Midwestern University, Downers Grove, IL 60515, USA
4
Department of Pharmacology, College of Graduate Studies, Midwestern University, Downers Grove, IL 60515, USA
*
Author to whom correspondence should be addressed.
Toxins 2020, 12(5), 333; https://doi.org/10.3390/toxins12050333
Received: 19 March 2020 / Revised: 13 May 2020 / Accepted: 14 May 2020 / Published: 19 May 2020
(This article belongs to the Section Bacterial Toxins)
The possible relationship between periodontal disease resulting from the infection of gingival tissue by the Gram-negative bacterium Porphyromonas gingivalis (P. gingivalis) and the development of neuroinflammation remains under investigation. Recently, P. gingivalis lipopolysaccharide (LPS) was reported in the human brain, thus suggesting it might activate brain microglia, a cell type participating in neuroinflammation. We tested the hypothesis of whether in vitro exposure to ultrapure P. gingivalis LPS may result in classical and alternative activation phenotypes of rat microglia, with the concomitant release of cytokines and chemokines, as well as superoxide anion (O2), thromboxane B2 (TXB2), and matrix metalloprotease-9 (MMP-9). After an 18-h exposure of microglia to P. gingivalis LPS, the concentration-dependent responses were the following: 0.1–100 ng/mL P. gingivalis LPS increased O2 generation, with reduced inflammatory mediator generation; 1000–10,000 ng/mL P. gingivalis LPS generated MMP-9, macrophage inflammatory protein 1α (MIP-1α/CCL3), macrophage inflammatory protein-2 (MIP-2/CXCL2) release and significant O2 generation; 100,000 ng/mL P. gingivalis LPS sustained O2 production, maintained MMP-9, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) release, and triggered elevated levels of MIP-1α/CCL3, MIP-2/CXCL2, and cytokine-induced neutrophil chemoattractant 1 (CINC-1/CXCL-1), with a very low release of lactic dehydrogenase (LDH). Although P. gingivalis LPS was less potent than Escherichia coli (E. coli) LPS in stimulating TXB2, MMP-9, IL-6 and interleukin 10 (IL-10) generation, we observed that it appeared more efficacious in enhancing the release of O2, TNF-α, MIP-1α/CCL3, MIP-2/CXCL2 and CINC-1/CXCL-1. Our results provide support to our research hypothesis because an 18-h in vitro stimulation with ultrapure P. gingivalis LPS resulted in the classical and alternative activation of rat brain microglia and the concomitant release of cytokines and chemokines. View Full-Text
Keywords: microglia; Porphyromonas gingivalis; Escherichia coli; lipopolysaccharide; neuroinflammation; periodontitis microglia; Porphyromonas gingivalis; Escherichia coli; lipopolysaccharide; neuroinflammation; periodontitis
Show Figures

Figure 1

MDPI and ACS Style

Memedovski, Z.; Czerwonka, E.; Han, J.; Mayer, J.; Luce, M.; Klemm, L.C.; Hall, M.L.; Mayer, A.M.S. Classical and Alternative Activation of Rat Microglia Treated with Ultrapure Porphyromonas gingivalis Lipopolysaccharide In Vitro. Toxins 2020, 12, 333.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop