Evaluation of miR-146a expression level in macrophages exposed to Candida glabrata


1 Department of Medical Parasitology and Mycology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran

2 Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran

3 Department of Medical Genetics, School of Advanced Medical Technologies, Golestan University of Medical Sciences, Gorgan, Iran

4 Infectious Diseases and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran


Background and Purpose: MicroRNAs are small non-coding RNAs with 1924- nucleotides in length. Up- or downregulation
of many miRNAs has been shown by stimulation of Toll-like receptors (TLRs) in the innate immune system.
Up-regulation of miR-146a has been reported by both TLR and heat-killed Candida albicans. In this study, we aimed to
evaluate the expression of miR-146a in cultured monocyte-derived macrophages (MDMs) infected by Candida glabrata
at 12, 24, and 48 hours.
Materials and Methods: miR-146a expression was evaluated by qRT-real time polymerase chain reaction (PCR) at three
time points in C. glabrata-infected MDMs. The data was analyzed using repeated measures ANOVA.
Results: miR-146a expression was down-regulated in infected MDMs compared to the control group (p <0.018). The
expression of miR-146a was at its highest level at 48 h, as compared to 12 and 24 h (p <0.018). The differences between
the experimental group compared to the control group were statistically significant (p <0.018).
Conclusion: These results suggest that miR-146a can be involved in regulating macrophage function following TLR
stimulation in C. glabrata-infected MDMs.


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