Abstract
Dorzolamide (DZD), a Carbonic anhydrase (CA) inhibitor clinically used
to lower intraocular pressure, exhibits anti-inflammatory effects owing
to the drug’s ability to inhibit the TIR domain-containing adaptor
protein (TIRAP)-mediated signaling in macrophages. Here, we investigated
whether DZD intermediates also demonstrate any anti-inflammatory
property like DZD but with a reduced inhibition of CA. We found that
several intermediates of DZD show increased binding to TIRAP at the
common interface of kinases, such as Protein kinase C-delta (PKCδ) and
Bruton’s tyrosine kinase (BTK). Such binding results in a decreased
activity of TIRAP, p38 (Mitogen-activating protein kinases) MAPK, and
p65, which are essential for major inflammatory signaling pathways.
Remarkably, the DZD intermediates were more potent than DZD in
decreasing the mRNA expression levels of pro-inflammatory cytokines in
LPS-stimulated RAW 264.7 cells. The DZD intermediates also exhibit a
reduced binding energy to CA II and CA IV, highlighting their improved
specificity as anti-inflammatory compounds with decreased unwanted
biological effects. Furthermore, we validated the anti-inflammatory
effect of the most potent DZD intermediate, DRZ V, in a model of mouse
sepsis. DRZ V-treated septic mice exhibited improved survival compared
to DZD-treated septic mice. Our data indicate that the tested DZD
intermediates are more potent in dampening TIRAP-mediated inflammatory
signaling as compared to DZD. Thus, DZD intermediates may be a promising
option for developing novel anti-inflammatory therapeutics.