Investigation of hydrogen peroxide and nitric oxide signaling utilızing genetically encoded biosensors.

The relationship between hydrogen peroxide (H2O2) and nitric oxide (NO) is a criticalyet complex aspect of redox biology, with significant implications for cellular signalingand oxidative stress-related diseases. This study aims to demonstrate this relationshipusing genetically encoded biosensors, HyPer7 for H2O2 and O-geNOp for NO, in livecellimaging. We developed and optimized these tools to achieve high selectivity andspatial resolution, addressing challenges related to simultaneous measurement of reactiveoxygen species (ROS) and reactive nitrogen species (RNS). Our experimentsdemonstrated that cells adapted to physiological normoxia (5 kPa O2) exhibit enhancedantioxidant capacity and NO bioavailability compared to those adapted to hyperoxia (18kPa O2). Using a dual-biosensor endothelial cell line, we investigated the effects of H2O2production on NO dynamics and discovered that physiological normoxia conditionssignificantly improve cellular redox balance. These findings provide new insights into theinterplay between H2O2 and NO, highlighting the importance of maintainingphysiological O2 levels for optimal cellular function. The results also underscore thepotential of genetically encoded biosensors as powerful tools for studying redox signalingin live cells, paving the way for novel therapeutic strategies targeting oxidative stressrelatedpathologies.