miR-584 expressed in human gingival epithelial cells is induced by Porphyromonas gingivalis stimulation and regulates interleukin-8 production via lactoferrin receptor.
BACKGROUND
MicroRNAs (miRNAs) are short, non-coding RNAs that are involved in post-transcriptional regulation of gene expression. Differential miRNA expression in innate and acquired immunity has been shown to regulate immune cell development and function. miRNA expression has been demonstrated to affect pathophysiology of inflammatory diseases, such as rheumatoid arthritis and lupus. As such, this study explores the role of miRNA in the context of pathophysiology of destructive periodontitis. Specifically, this investigation profiles the differentially expressed miRNA of Porphyromonas gingivalis (Pg)-stimulated human gingival epithelial cells (HGECs).


METHODS
The specific miRNAs differentially expressed in Pg-stimulated OBA-9, immortalized HGECs, were analyzed using microarray. Real-time polymerase chain reaction (PCR) and Western blotting were performed to confirm the level of miRNA expression and determine target production of miRNA in OBA-9. The production of interleukin (IL)-8 was measured to determine the bioactivity of target protein regulated by miRNA.


RESULTS
miR-584, which targets lactoferrin receptor (LfR), was 3.39-fold upregulated by Pg stimulation. This upregulation of miR-584 was confirmed by real-time PCR. Pg stimulation resulted in the suppression of LfR at mRNA and protein levels. The transfection of the miR inhibitor for miR-584 in OBA-9 recovered Pg-induced suppression of LfR. The addition of human lactoferrin (hLf) had a suppressive effect on IL-8 production in Pg-stimulated OBA-9. However, hLf also decreased IL-8 production strongly in Pg-stimulated OBA-9 in the presence of the miR inhibitor for miR-584.


CONCLUSIONS
These findings suggest that the upregulation of miR-584 by Pg in OBA-9 inhibits the anti-inflammatory effects of hLf via the suppression of LfR.
Department of Periodontal Medicine, Division of Applied Life Sciences, Institute of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.
Kazuhisa
K
Ouhara
Irma Josefina
IJ
Savitri
Tsuyoshi
T
Fujita
Mizuho
M
Kittaka
Mikihito
M
Kajiya
Tomoyuki
T
Iwata
Tsuyoshi
T
Miyagawa
Masahiro
M
Yamakawa
Hideki
H
Shiba
Hidemi
H
Kurihara
D000328:Adult; D016976:Aggregatibacter actinomycetemcomitans / Q000276:immunology; D002461:Cell Line, Transformed; D002478:Cells, Cultured; D018920:Coculture Techniques; D004847:Epithelial Cells / Q000276:immunology / Q000382:microbiology; D005260:Female; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics; D055785:Gene Knockdown Techniques; D005881:Gingiva / Q000166:cytology* / Q000276:immunology / Q000382:microbiology; D006801:Humans; D018836:Inflammation Mediators / Q000032:analysis / Q000276:immunology; D016209:Interleukin-8 / Q000032:analysis / Q000235:genetics*; D007781:Lactoferrin / Q000032:analysis / Q000235:genetics*; D035683:MicroRNAs / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000276:immunology; D016966:Porphyromonas gingivalis / Q000276:immunology*; D011956:Receptors, Cell Surface / Q000032:analysis / Q000235:genetics*; D015854:Up-Regulation; D055815:Young Adult
C508606:CXCL8 protein, human; D018836:Inflammation Mediators; D016209:Interleukin-8; C552781:MIRN584 microRNA, human; D035683:MicroRNAs; D011956:Receptors, Cell Surface; C038340:lactoferrin receptors; D007781:Lactoferrin
Epithelial cells; Porphyromonas gingivalis; inflammation; interleukin-8; microRNAs; periodontitis