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Metabolic Pathway Tracing for NAD+ Synthesis and Consumption
Tumpa Dutta1, Stephen J Gardell2
1Translational Research Institute, AdventHealth, Orlando, FL, USA. tumpa.dutta@adventhealth.com.
Methods in Molecular Biology (Clifton, N.J.)
|June 11, 2025
Summary
Nicotinamide adenine dinucleotide (NAD+) is crucial for metabolism and health. Metabolic pathway tracing reveals how NAD+ synthesis and consumption impact levels, offering insights into aging and disease.
Area of Science:
- Biochemistry
- Metabolomics
- Aging Research
Background:
- Nicotinamide adenine dinucleotide (NAD+) is a vital cellular metabolite involved in metabolism, redox reactions, and cellular signaling.
- Declining NAD+ levels are associated with aging and chronic diseases, but the underlying causes (synthesis vs. consumption) are unclear.
- Static NAD+ measurements are insufficient to understand the dynamic metabolic pathways governing its levels.
Purpose of the Study:
- To investigate the dynamic processes of NAD+ synthesis and consumption.
- To elucidate the contributions of different pathways to steady-state NAD+ concentrations.
- To critically evaluate the role of NAD+ metabolism in aging and disease.
Main Methods:
- Metabolic pathway tracing using stable isotope-labeled NAD+ precursors (e.g., nicotinamide, nicotinic acid, tryptophan).
- High-resolution mass spectrometry (HRMS) to track precursor fate and metabolic products (NADH, NADP, NADPH).
- Analysis of NAD+ synthesis and degradation pathways in various biological samples (cells, tissues, biofluids).
Main Results:
- Metabolic pathway tracing successfully differentiated NAD+ synthesis and consumption rates.
- The technique identified the metabolic fate of NAD+ precursors and downstream products.
- This approach is applicable across diverse biological systems from cell cultures to clinical samples.
Conclusions:
- Metabolic pathway tracing is a versatile tool for understanding NAD+ homeostasis.
- It provides critical insights into the dynamic regulation of NAD+ metabolism.
- This technique can help clarify the link between NAD+ levels, aging, and chronic diseases.
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