ACE2 and viral infectious disease: NF-κB-dependent induction of miR-200c-3p is a shared mechanism of H5N1-vRNA, poly (I:C), LPS and LTA induced ACE2 reduction, suggesting a molecular mechanism of ALI/ARDS caused by bacterial and viral infections: the elevated miR-200c-3p downregulated ACE2 expression, increased Ang II levels and caused lung injury through Ang II type 1 receptor.