Ketone bodies are protective against oxidative stress in neocortical neurons.
Level 5 - mechanism / opinion, no new human data
Preclinical laboratory experiment using rat neuronal cultures, tissue slices, and isolated mitochondria (no human data).
PubMed 17403035 · doi:10.1111/j.1471-4159.2007.04483.x
What was done
Researchers investigated the neuroprotective mechanisms of ketone bodies against oxidative stress using rat neocortical preparations. Cultured rat neocortical neurons, brain slices, and isolated neocortical mitochondria were exposed to hydrogen peroxide or diamide (a thiol oxidant and activator of mitochondrial permeability transition, mPT). The study measured inward membrane currents, cell death via propidium iodide labeling, reactive oxygen species (ROS) levels, and the threshold for calcium-induced mPT, comparing ketone body effects to known mPT inhibitors and antioxidants.
What was found
The abstract reports directional findings without numerical values, effect sizes, or variance measures: - Ketone bodies completely blocked large inward currents induced by hydrogen peroxide or diamide, mimicking the actions of mPT inhibitors and antioxidants. - Ketone bodies significantly decreased propidium iodide-labeled cell death in neocortical slices exposed to hydrogen peroxide or diamide. - Ketone bodies significantly decreased ROS levels in dissociated neurons and isolated neocortical mitochondria. - Diamide alone did not significantly alter basal ROS levels in neurons. - Ketone bodies significantly increased the threshold for calcium-induced mPT in isolated mitochondria.
Why it matters
This study provides cellular-level mechanistic evidence that ketone bodies protect cortical neurons from oxidative injury, primarily by suppressing mitochondrial ROS production and inhibiting mitochondrial permeability transition pore opening.
Limits
The study is entirely in vitro and ex vivo using rat brain tissue, lacking in vivo validation and human clinical data. The abstract provides no quantitative data, effect sizes, statistical confidence intervals, or sample sizes (n = ?).
Cited by
- supports Metabolizing ketones generates fewer free radicals than metabolizing glucose in cells.