gluconeogenesis

fat -> acetone -> methylglyoxal -> pyruvate

it's quantitatively insignificant though

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88KB, 983x646px

>>8453428

>>8453452
Yeah, but during long fasts isn't it the main source of gluconeogenesis?

>Wikipedia says no
>Gluconeogenesis is one of several main mechanisms used by humans and many other animals to maintain blood glucose levels, avoiding low levels (hypoglycemia). Other means include the degradation of glycogen (glycogenolysis),[1] fatty acid breakdown.
What the fuck are you talking about OP

>>8453465
>>8453465
iirc, non-ketogenic amino acids and glycerol do the bulk of net glucose synthesis

see eg here

https://www.ncbi.nlm.nih.gov/pubmed/438326

>>8453452
Only this, which only occurs in minor scale after prolonged starvation I think.

>>8453484
That's for all organisms, not humans.

>The existence of glyoxylate cycles in humans has not been established, and it is widely held that fatty acids cannot be converted to glucose in humans directly. However, carbon-14 has been shown to end up in glucose when it is supplied in fatty acids.[13] Despite these findings, it is considered unlikely that the 2-carbon acetyl-CoA derived from the oxidation of fatty acids would produce a net yield of glucose via the citric acid cycle - however, acetyl-CoA can be converted into pyruvate and lactate through the ketogenic pathway.[10][14] Put simply, acetic acid (in the form of acetyl-CoA) is used to partially produce glucose; acetyl groups can only form part of the glucose molecules (not the 5th carbon atom) and require extra substrates (such as pyruvate) in order to form the rest of the glucose molecule. But a roundabout pathway does lead from acetyl-coA to pyruvate, via acetoacetate, acetone, hydroxyacetone (acetol) and then either propylene glycol or methylglyoxal.[14][15][16]

>>8453428
Of course. People's glycogen isn't infinite, and blood cells have no mitochondria.

>Wikipedia says no

It says yes.

>>8453608
So human metabolic pathways are fucked up and we shouldn't properly be alive. What's new about that?