NADPH oxidase 2 inhibitors CPP11G and CPP11H attenuate endothelial cell inflammation & vessel dysfunction and restore...

Area of Science:

• Biochemistry
• Immunology
• Pharmacology

Background:

• Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (Nox2)-derived reactive oxygen species (ROS) are implicated in diverse cellular responses, but their role in inflammation requires further elucidation.
• Tumor necrosis factor-alpha (TNFα) is a key pro-inflammatory cytokine that induces ROS generation and signaling in endothelial cells.

Purpose of the Study:

• To investigate the therapeutic potential of novel Nox2 inhibitors (CPP11G and CPP11H) in mitigating TNFα-induced inflammation.
• To elucidate the mechanism of action of these inhibitors on Nox2 activity and downstream signaling pathways.

Main Methods:

• In silico modeling of Nox2 inhibitors.
• In vitro studies using human cells to assess inhibitor effects on p47phox translocation, ROS production, MAPK signaling, and transcription factor nuclear translocation (AP-1, NFκB).
• In vivo studies in mouse models of inflammation to evaluate the efficacy of Nox2 inhibition on ROS levels, inflammatory markers, and hind-limb blood flow.

Main Results:

• CPP11G and CPP11H effectively inhibited p47phox translocation to the plasma membrane, abolishing Nox2-derived ROS production.
• Inhibitors attenuated stress-responsive MAPK signaling and downstream AP-1 and NFκB activation in human cells.
• Targeted Nox2 inhibition significantly reduced endothelial cell adhesion molecule expression, monocyte adherence, and TNFα-induced inflammation in vivo, leading to improved hind-limb blood flow.

Conclusions:

• Nox2 plays a critical role in propagating TNFα-induced inflammatory signaling.
• Novel Nox2 inhibitors, CPP11G and CPP11H, demonstrate significant therapeutic potential for treating inflammatory diseases by targeting ROS generation and downstream signaling pathways.