onsdag 28 september 2016

Ketone bodies are protective against oxidative stress in neocortical neurons - Kim - 2007 - Journal of Neurochemistry - Wiley Online Library

http://onlinelibrary.wiley.com/doi/10.1111/j.1471-4159.2007.04483.x/full


"Abstract



Ketone bodies (KB) have been shown to
prevent neurodegeneration in models of Parkinson’s and Alzheimer’s diseases,
but the mechanisms underlying these effects remain unclear. One possibility is
that KB may exert antioxidant activity. In the current study, we explored the
effects of KB on rat neocortical neurons exposed to hydrogen peroxide (H
2O2) or diamide – a thiol oxidant
and activator of mitochondrial permeability transition (mPT). We found that:
(i) KB completely blocked large inward currents induced by either H
2O2 or diamide; (ii) KB
significantly decreased the number of propidium iodide-labeled cells in
neocortical slices after exposure to H
2Oor diamide; (iii) KB significantly decreased
reactive oxygen species (ROS) levels in dissociated neurons and in isolated
neocortical mitochondria; (iv) the electrophysiological effects of KB in
neurons exposed to H
2Oor diamide were mimicked by bongkrekic acid and cyclosporin A, known
inhibitors of mPT, as well as by catalase and DL
– dithiothreitol, known
antioxidants; (v) diamide alone did not significantly alter basal ROS levels in
neurons, supporting previous studies indicating that diamide-induced neuronal
injury may be mediated by mPT opening; and (vi) KB significantly increased the
threshold for calcium-induced mPT in isolated mitochondria. Taken together, our
data suggest that KB may prevent mPT and oxidative injury in neocortical
neurons, most likely by decreasing mitochondrial ROS production."

Kim, D. Y., Davis, L. M., Sullivan, P. G., Maalouf, M., Simeone, T. A., Brederode, J. v. and Rho, J. M. (2007), Ketone bodies are protective against oxidative stress in neocortical neurons. Journal of Neurochemistry, 101: 1316–1326. doi:10.1111/j.1471-4159.2007.04483.x

söndag 25 september 2016

Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. - PubMed - NCBI

https://www.ncbi.nlm.nih.gov/m/pubmed/20071648/?i=3&from=Siri-Tarino%20PW,%20Sun%20Q,%20Hu%20FB,%20Krauss%20RM



"CONCLUSIONS: A meta-analysis of prospective epidemiologic studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD. More data are needed to elucidate whether CVD risks are likely to be influenced by the specific nutrients used to replace saturated fat."


Siri-Tarino PW, Sun Q, Hu FB,
Krauss RM. Meta-analysis of prospective cohort studies evaluating the
association of saturated fat with cardiovascular disease. Am J Clin
Nutr 2010;91:535-46.