Pharmacological effects of ?-D-mannuronic acid (M2000) on miR-146a, IRAK1, TRAF6 and NF-?B gene expression, as target molecules in inflammatory reactions

Abstract

Background Impaired expression and function of microRNAs (miRNAs) are involved in the pathogenesis of many autoimmune and inflammatory diseases. Moreover, there is a close relationship between TLRs and miRNAs and impairment in regulating their expression which can play a vital role in the immunopathogenesis of many inflammatory reactions. This research aimed to study the pharmaceutical effects of M2000 (?-D-mannuronic acid) on the expression of miR-146a and its two target molecules (IRAK1 and TRAF6), and the transcription factor NF-?B in the HEK-Blue hTLR2 cell line. Methods The cytotoxicity of M2000 was assessed by the MTT assay, and the qRT-PCR technique was employed in the presence and absence of M2000 treatment to measure gene-expression levels of miR-146a, IRAK1, TRAF6, and NF-?B. Results MTT assay indicated that M2000 (before the concentration of 500ط¢آ ?g/ml) had no cytotoxic effect on HEK-Blue hTLR2 cells. Our results showed that M2000 at low and high doses (5 and 25ط¢آ ?g/well) could significantly reduce gene expression levels of miR-146a (pط¢آ <ط¢آ 0.01). Furthermore, it was found that this medication at two different doses could considerably decrease IRAK1 and TRAF6 gene expression (pط¢آ <ط¢آ 0.001). Moreover, this study revealed that expression level of NF-?B also significantly declined at these two doses (pط¢آ <ط¢آ 0.01). Conclusions This study for the first time shows that M2000 as a novel NSAID with immunosuppressive properties is able to modify TLR signaling through suppressing the adaptor molecules IRAK1 and TRAF6, the transcription factor NF-?B and miR-146a as a new therapeutic approach. ط¢آ© 2017 Institute of Pharmacology, Polish Academy of Sciences