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Preparation of Rat Skeletal Muscle Homogenates for Nitrate and Nitrite Measurements
Published on: July 29, 2021
Dietary inorganic nitrate improves mitochondrial efficiency in humans
Filip J Larsen1, Tomas A Schiffer, Sara Borniquel
1Department of Physiology and Pharmacology, Karolinska Institutet, 11486 Stockholm, Sweden. filip.larsen@ki.se
Cell Metabolism
|February 3, 2011
Summary
Dietary nitrate supplementation improves mitochondrial efficiency and reduces exercise oxygen cost in healthy adults. This mechanism involves enhanced oxidative phosphorylation and reduced proton leak in skeletal muscle mitochondria.
Area of Science:
- Exercise physiology
- Mitochondrial biology
- Nutritional science
Background:
- Dietary nitrate, found in vegetables, converts to nitric oxide (NO) in vivo.
- Previous research showed dietary nitrate reduces exercise oxygen cost, but the mechanism was unclear.
- Mitochondrial dysfunction is implicated in various lifestyle-related disorders.
Purpose of the Study:
- To investigate the effects of dietary nitrate on basal mitochondrial function and whole-body oxygen consumption.
- To elucidate the mechanism by which nitrate reduces exercise oxygen cost.
- To assess the impact of nitrate on skeletal muscle mitochondrial efficiency.
Main Methods:
- Double-blind, crossover trial in healthy volunteers.
- Dietary intervention with inorganic nitrate.
- Measurement of mitochondrial oxidative phosphorylation (P/O ratio) and respiration.
- Analysis of ATP/ADP translocase expression.
Main Results:
- Nitrate supplementation improved mitochondrial oxidative phosphorylation efficiency (P/O ratio).
- Reduced state 4 respiration and respiration without adenylates were observed.
- Improved P/O ratio correlated with reduced exercise oxygen cost.
- Nitrate decreased ATP/ADP translocase expression, a proton conductance regulator.
Conclusions:
- Dietary nitrate significantly enhances basal mitochondrial function.
- Improved mitochondrial efficiency is a key mechanism for reduced exercise oxygen cost.
- Findings suggest potential therapeutic implications for mitochondrial disorders and exercise performance.
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