Elucidation of the molecular mechanism underlying the anti-inflammatory activity of an effective and safe bipyrazole-based compound

Abstract

Introduction: Since the synthesis of acetylsalicylic acid by Hoffmann in 1897, new classes of NSAIDs have been introduced; however, their side effects have limited their clinical applications. Consequently, our team has recently synthesized a novel bipyrazole compound that showed a satisfactory efficacy and safety profile. The aim of the current study was to elucidate the molecular mechanism of this bipyrazole compound.

Method: The anti-inflammatory efficacy of the compound was assessed using formalin-induced paw edema test. Computer-assisted simulation docking experiments were carried out. Cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), neuronal nitric oxide synthase (nNOS), tumor necrosis factor-alpha (TNFα), interleukin-1 (IL1) and interleukin-10 (IL10) gene expression were quantified with real-time polymerase chain reaction (RT-PCR) using SYBR Green technology. The samples were taken from the plantar paw of mice after formalin local injection.

Results: The efficacy of the bipyrazole compound was similar to that of indomethacin, diclofenac, and celecoxib, as proven by the formalin-induced paw edema. Docking study indicated a superior binding score for the studied compound relative to celecoxib, indomethacin, and diclofenac. RT-PCR assessment revealed a significant decrease in iNOS, COX-2, and TNFα gene expression in the bipyrazole-treated group. Moreover, a reduction in IL1 and nNOS gene expression levels and an increase in IL10 level were detected despite being insignificant compared to the control group.

Conclusion: These findings revealed the superiority of the newly synthesized bipyrazole compound not only on the binding site, but also by inhibiting most of the inflammatory mediators including TNF-α.

Keywords: Bipyrazole; Cyclooxygenase-2 (COX-2); Inducible nitric oxide synthase (iNOS); Neuronal nitric oxide synthase (nNOS); Non-steroidal anti-inflammatory drugs; Tumor necrosis factor-alpha (TNF-α).