Kohlenhydrate, Kaloric Restriction and how to lose Fat

[sekt88]

Erste Lekture: Sorry but the journal is in English.

CR: Caloric Restriction
ROS: Reactive Oxygen Species

Falls Jemand Interesse hat, kann ich gerne das gesamtes Pdf zu schicken.

Cell, Vol 132, 171-176, 25 January 2008
Essay
Mitochondria—A Nexus for Aging, Calorie Restriction, and Sirtuins?
Leonard Guarente1,∗
1 Department of Biology, Massachusetts Institute of Technology, Cambridge MA 02139, US
Mitochondrial Reprogramming to Fat Oxidation

CR changes the way in which different available energy sources in food are handled by the body. In caloric excess, carbohydrates are used for energy and fat is stored, presumably because it has a higher energy content per gram. However, during CR all energy sources are used, notably fat and amino acids, and the animal minimizes carbohydrate use in peripheral tissues to maintain adequate blood glucose levels for the brain (Weindruch et al., 1988). Therefore, in energy-producing tissues like muscle, there is a shift toward the β-oxidation of fatty acids to derive energy during CR, a process that occurs in mitochondria.

Unlike carbohydrate catabolism, in which most of the reducing power generated for electron transport is in the form of NADH, β-oxidation of fatty acids produces FADH at a molar equivalence of NADH. FADH must enter the electron transport chain not via complex I but via the electron transfer flavoprotein dehydrogenase (ETF) (coupled to acyl-CoA dehydrogenase) (Figure 2). ETF passes electrons to ubiquinone, which then donates them to complex III and thence onward down the chain. Therefore, use of fat as an energy source increases the frequency with which electrons enter the electron transport chain by bypassing complex I. Given that complex I is one of the primary stations of ROS production, this simple metabolic shift from carbohydrate to fat utilization may reduce ROS production.

But what about the increase in mitochondrial biogenesis observed during CR? When electrons enter the electron transport chain at complex I, their transport results in the synthesis of three molecules of ATP by oxidative phosphorylation. However, when electrons enter at ETF only two ATP molecules are made because the proton-pumping complex I has been bypassed. Thus, it is possible that the observed mitochondrial biogenesis during CR compensates for the reduction in ATP production per reducing equivalent when fat is used as an energy source. This model would suggest that it is not an increase in respiration or even mitochondrial biogenesis per se that is beneficial during CR but rather the partial bypass of complex I in the production of ATP. In this regard, it is interesting to note that the human CR trial did not record any increase in respiration but actually showed a decrease in whole body energy expenditure (Civitarese et al., 2007), even though there was an increase in mitochondrial components.

As for model three, this idea is appealing for its simplicity but bears the caveat of placing great emphasis on the importance of ROS in aging. It is interesting to note that one of the most effective drugs for diabetes, metformin, can act as a partial inhibitor of complex I (Owen et al., 2000). Much of the benefit of this drug in treating metabolic disease has been attributed to the resulting activation of AMP-dependent protein kinase (AMPK) (Zhou et al., 2001), which helps to reduce gluconeogenesis in liver and to drive the oxidation of fat in muscle. However, it is clearly possible that the inhibition of complex I per se can help to reduce cellular damage and to foster long-term health benefits in metformin-treated individuals. The activation of AMPK may still serve an important regulatory role by inducing fatty-acid oxidation to ensure the maintenance of energy production.

[sprudel]

...der teamname in der sig ist falsch!

[sekt88]

Zitat von sprudel

...der teamname in der sig ist falsch!

Ja, Ja....CR bietet einen interessantes wirkung für Ausdauer training, aber nur wenn es Kapiert ist.


Doctor for Team Nucking Futz,

Sektt8

[pisskopp]

Man sollte hierbei auch beachten, dass eine ausgeglichene, nerosynaptische modifikationssyntese, das reziproge Ergebnis, speziell im GA1, impliziert.
Daraus lässt sich ein derivat bilden welches redundant den Schluss zulässt, dass das alles blöder Mist ist.
Geht biken

[x-rossi]

ich bin so froh, dass pisskopf auf meiner ignore-liste ist. echt jetzt!

[pisskopp]

Warum schreibst du das hier?
Wenn Du mich doch ignorieren würdest, müsstest Du hier und jetzt nix posten?

[prozak]

pisskopp, welchen sinn hast du?

[pisskopp]

frägt wer?

Ach ja und bitte, erkläre mir,allwissend, den Sinn des threads

[Karwendelfuchs]

Hab das Paper gestern bekommen, Danke nochmal!

Der Sinn hinter solchen Sachen besteht darin etwas über den Tellerrand zu blicken und zu verstehen wieso die ganzen Wundermittelchen á la L- Carnitin, Creatin, Protein usw... nichts bringen sondern die ausgewogene Ernährung der Schlüssel zu GESUNDEM Erfolg ist!

[sekt88]

Zitat von Karwendelfuchs

Hab das Paper gestern bekommen, Danke nochmal!

Der Sinn hinter solchen Sachen besteht darin etwas über den Tellerrand zu blicken und zu verstehen wieso die ganzen Wundermittelchen á la L- Carnitin, Creatin, Protein usw... nichts bringen sondern die ausgewogene Ernährung der Schlüssel zu GESUNDEM Erfolg ist!

Danke für diese ANtwort. Mein Deutsch ist nicht gut genug solche satz zu formulieren.

[sekt88]

Zitat von pisskopp

den Sinn des threads

Hinweis für pisskopp: CR fordert MITOCHONDRIAL BIOGENESIS.

Falls das dir nicht etwas sagt, dann tu mir ein gefallen und kein mehr Antwort in diesen Thread schreiben.

Danke,

Sekt88

[pisskopp]

Ok ich halte mich raus, ich bekehre mich nur zur Protein phosphorylation in yeast mitochondria.

Schikkes Bild