Dynamic and differential renal cortical cell-specific mitochondrial metabolism in response to fasting.
Level 5 - mechanism / opinion, no new human data
Preclinical animal model study (CEBM Level 5).
PubMed 41428383 · doi:10.1152/ajprenal.00235.2025
What was done
Researchers developed transgenic mouse models to isolate cell-specific mitochondria from the kidney using the MITO-Tag system combined with Cre drivers targeting the early proximal tubule (PT; Slc34a1-CreERT2), late PT (Ggt1-Cre), and distal convoluted tubule (DCT; Pvalb-Cre). Mitochondria were immunoprecipitated using anti-HA antibodies from ad libitum-fed and 24-hour fasted male mice to assess mitochondrial respiratory capacity, fatty acid oxidation (FAO) capacity, and metabolomic profiles across nephron segments.
What was found
The authors observed that baseline mitochondrial respiratory and FAO capacities varied across early PT, late PT, and DCT segments, and that these functional capacities adapted dynamically and differentially in response to 24 hours of fasting. The abstract did not report specific numerical values, effect sizes, or statistical metrics.
Why it matters
This establishes the utility of the MITO-Tag system in the kidney and demonstrates that distinct nephron segments have distinct mitochondrial functional capacities and metabolic responses to nutrient deprivation.
Limits
The study was conducted exclusively in a preclinical mouse model, and the abstract omitted sample sizes. The experiments evaluated only male mice during acute fasting and did not assess female animals, chronic metabolic conditions, or human kidney tissue.
Cited by
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