Cell-specific image-guided transcriptomics identifies complex injuries caused by ischemic acute kidney injury in mice

Area of Science:

• Nephrology
• Molecular Biology
• Biochemistry

Background:

• Identifying cell-specific molecular pathways in the kidney during acute kidney injury (AKI) is challenging.
• Temporal association of cellular responses with AKI pathophysiology requires advanced tools.

Purpose of the Study:

• To develop and apply novel methods for cell-specific transcriptional analysis in AKI.
• To investigate the impact of AKI on mitochondrial pathways in kidney collecting duct cells.
• To evaluate the therapeutic potential of targeting mitochondrial dysfunction in AKI.

Main Methods:

• Utilized renal cell-specific luciferase reporter mice and chemoselective luciferin for cell-specific transcriptional profiling.
• Employed peroxy-caged-luciferin to monitor hydrogen peroxide generation and determine optimal time points for ribosome immunoprecipitation.
• Performed RNA-sequencing on labeled ribosomes to capture cell-specific transcriptomic changes.
• Integrated physiological imaging, transcriptomics, and drug testing (antioxidant treatment).

Main Results:

• Demonstrated a significant impact of AKI on mitochondrial pathways specifically within the collecting duct.
• Showed that antioxidant treatment targeting mitochondria ameliorated hydrogen peroxide generation and reduced oxidative stress.
• Observed a significant reduction in the expression of the AKI biomarker LCN2 following antioxidant intervention.
• Successfully linked physiological imaging with transcriptomic data to understand AKI-induced changes.

Conclusions:

• The collecting duct exhibits a profound response to AKI, particularly involving mitochondrial pathways.
• Targeting mitochondrial dysfunction with antioxidants is a viable therapeutic strategy for AKI.
• This integrative approach enables cell-specific monitoring and treatment strategies for AKI.
• The developed tools offer new avenues for studying kidney pathophysiology.