Newsgroup: it.salute.alimentazione
Titolo: Chetoni A Scopo Terapeutico

Ma non erano dannosissimi per la salute?
Trans Am Clin Climatol Assoc. 2003;114:149-61; discussion 162-3.
Ketoacids? Good medicine?
Cahill GF Jr, Veech RL.
D-beta-hydroxybutyrate, the principal "ketone" body in starving man,
displaces glucose as the predominating fuel for brain, decreasing the need
for glucose synthesis in liver (and kidney) and accordingly spares its
precursor, muscle-derived amino acids. Thus normal 70 kg. man survives 2-3
months of starvation instead of several weeks, and obese man many months to
over a year. Without this metabolic adaptation, H. sapiens could not have
evolved such a large brain. Recent studies have shown that
D-beta-hydroxybutyrate, the principal "ketone", is not just a fuel, but a
"superfuel" more efficiently producing ATP energy than glucose or fatty
acid. In a perfused rat heart preparation, it increased contractility and
decreased oxygen consumption. It has also protected neuronal cells in tissue
culture against exposure to toxins associated with Alzheimer's or
Parkinson's. In a rodent model it decreased the death of lung cells induced
by hemorrhagic shock. Also, mice exposed to hypoxia survived longer. These
and other data suggest a potential use of beta-hydroxybutyrate in a number
of medical and non-medical conditions where oxygen supply or substrate
utilization may be limited. Efforts are underway to prepare esters of
beta-hydroxybutyrate which can be taken orally or parenterally to study its
potential therapeutic applications.
---
IUBMB Life. 2001 Apr;51(4):241-7.
Ketone bodies, potential therapeutic uses.
Veech RL, Chance B, Kashiwaya Y, Lardy HA, Cahill GF Jr.
Unit on Metabolic Control, LMMB/NIAAA, Rockville, Maryland, USA.
Ketosis, meaning elevation of D-beta-hydroxybutyrate (R-3hydroxybutyrate)
and acetoacetate, has been central to starving man's survival by providing
nonglucose substrate to his evolutionarily hypertrophied brain, sparing
muscle from destruction for glucose synthesis. Surprisingly,
D-beta-hydroxybutyrate (abbreviated "betaOHB") may also provide a more
efficient source of energy for brain per unit oxygen, supported by the same
phenomenon noted in the isolated working perfused rat heart and in sperm. It
has also been shown to decrease cell death in two human neuronal cultures,
one a model of Alzheimer's and the other of Parkinson's disease. These
observations raise the possibility that a number of neurologic disorders,
genetic and acquired, might benefit by ketosis. Other beneficial effects
from betaOHB include an increased energy of ATP hydrolysis (deltaG') and its
linked ionic gradients. This may be significant in drug-resistant epilepsy
and in injury and anoxic states. The ability of betaOHB to oxidize co-enzyme
Q and reduce NADP+ may also be important in decreasing free radical damage.
Clinical maneuvers for increasing blood levels of betaOHB to 2-5 mmol may
require synthetic esters or polymers of betaOHB taken orally, probably 100
to 150 g or more daily. This necessitates advances in food-science
technology to provide at least enough orally acceptable synthetic material
for animal and possibly subsequent clinical testing. The other major need is
to bring the technology for the analysis of multiple metabolic "phenotypes"
up to the level of sophistication of the instrumentation used, for example,
in gene science or in structural biology. This technical strategy will be
critical to the characterization of polygenic disorders by enhancing the
knowledge gained from gene analysis and from the subsequent steps and
modifications of the protein products themselves.
--------------------------------
Inviato via 
http://usenet.libero.it

 Ma non erano dannosissimi per la salute?
Per i più distratti aggiungo questo già citato link
http://www.ketosis-ketoacidosis-difference.com/
Ciao!
Gianni