Three-dimensional vascular and metabolic imaging using inverted autofluorescence.

Area of Science:

• Biomedical Imaging
• Physiology
• Vascular Biology

Background:

• Three-dimensional (3D) imaging of whole rodent organs offers vital insights into vascular networks and pathophysiology.
• Autofluorescence metabolic imaging, utilizing mitochondrial metabolites like NADH and FAD, is established for metabolic evaluation.

Purpose of the Study:

• To develop a 3D vascular segmentation technique for delineating vasculature and mitochondrial metabolic distribution in whole rodent organs.
• To integrate autofluorescence metabolic imaging with vascular segmentation for comprehensive organ analysis.

Main Methods:

• Utilized VMI by measuring natural fluorescence from mitochondrial metabolites and hemoglobin's light absorption.
• Applied 3D vascular segmentation to rodent lungs, kidneys, hearts, and livers.
• Employed exogenous fluorescent dye for lung airway separation and genetically engineered rats for kidney vasculature validation.

Main Results:

• Successfully mapped the 3D vascular tree structure in multiple rodent organs.
• Validated VMI against genetically engineered rat vasculature, aligning with Murray's law.
• Demonstrated vascular regression in rats induced by ionizing radiation using the VMI approach.

Conclusions:

• Simultaneous vascular and metabolic data from VMI yield quantitative diagnostic markers.
• This method avoids confounding effects from traditional vascular stains or contrast agents.
• VMI offers a powerful tool for studying vascular networks and metabolic states in animal models.