can someone explain how hormones regulate metabolic pathways and how metabolic pathways linkup?

[Kemosabe]

I think I have the basic idea down, but I may be a bit confused. There are two kinds of metabolic processes:
Anabolic - building molecules up which requires energy
Catabolic - breaking molecules down for energy.

Anabolic processes include - Gluconeogenesis, Glycogenesis, Pentose Phosphate cycle, and fatty acid synthesis.
Catabolic processes include - beta oxidation, glycolysis, TCA, etc, PDH, glycogenolysis, and fermentation.

In terms of hormonal control and allosteric control i'm a bit confused. Insulin involves signaling for glucose to be stored within cells so it'd make sense that it activates Glycogenesis, but instead it activates glycolysis, while glucagon for some reason inhibits glycolysis, which doesn't make much sense to me because glucagon is responsible for bringing glucose into blood and is associated with epinephrine and breaking down molecules into energy (catabolic processes). Can someone explain this? Epinephrine also should activate all the major catabolic metabolic pathways if i'm correct too. It also seems like acetyl-coa activates a good portion of anabolic processes, but also the TCA. Is that accurate? What are some other important details?

My other question is about connections between metabolic pathways. Do I have all of the major ideas?:
Basically from what I understand they're all linked to each other and various substrates can enter pathways at certain points, amino acids can be broken into acetyl-coa with amino transferases, other sugars can enter glycolysis at certain points, fatty acids can be converted into acetyl-coa and used for TCA or if the body is deprived of nutrition can be used converted to ketone bodies and then converted to acetyl coa once they're inside the brain.

catabolic and anabolic pathways are linked and depending on the body's needs a different set of metabolic pathways will be stimulated.

Gluconeogenesis is the reverse of glycolysis with a few changes and is done when the body needs more glucose.
Pentose phosphate pathway supplies the body with building blocks for Nucleic acids and NADPH that can be used in fatty acid synthesis. Anabolic pathways allow the body to build up macromolecules to use for catabolic pathways.

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[NeuroMaster316]

First, glycolysis ==> Using glucose and transforming it to pyruvate, i.e. this process would DECREASE glucose blood levels. With that in mind, when you have high blood glucose levels insulin will activate both Glycogenesis and Glycolysis.
Glucagon will obviously inhibit Glycolysis and activate Glycogenolysis AND Gluconeogenesis.
To keep things simple, epinephrine will stimulate the increase in blood glucose levels and glycolysis so that ATP is produced for the muscles. It will also stimulate lipolysis. But be careful glycolysis is actually inhibited in the liver and stimulated in the muscles, and that's because glucose is required by the muscles and the liver is the reservoir for glucose.
Acetyl-CoA is part of the TCA cycle.
Regarding everything else, you seem to be getting confused by the different biochemical pathway available which is normal but don't overthink anything. Everything you need to know is available in your review books.

 

[Kemosabe]

First, glycolysis ==> Using glucose and transforming it to pyruvate, i.e. this process would DECREASE glucose blood levels. With that in mind, when you have high blood glucose levels insulin will activate both Glycogenesis and Glycolysis.
Glucagon will obviously inhibit Glycolysis and activate Glycogenolysis AND Gluconeogenesis.
To keep things simple, epinephrine will stimulate the increase in blood glucose levels and glycolysis so that ATP is produced for the muscles. It will also stimulate lipolysis. But be careful glycolysis is actually inhibited in the liver and stimulated in the muscles, and that's because glucose is required by the muscles and the liver is the reservoir for glucose.
Acetyl-CoA is part of the TCA cycle.
Regarding everything else, you seem to be getting confused by the different biochemical pathway available which is normal but don't overthink anything. Everything you need to know is available in your review books.

Thank you so much for your response. What you said about insulin, glucagon, and epinephrine makes a lot of sense. One question - Where else do I seem to be getting confused about metabolic pathways in my post or anything else that I said that's wrong/what else am I missing? I've been reviewing metabolic pathways a lot in the books I have, so if there's anything else you think I may be missing I'll definitely do some research on it.

 

[NeuroMaster316]

Thank you so much for your response. What you said about insulin, glucagon, and epinephrine makes a lot of sense. One question - Where else do I seem to be getting confused about metabolic pathways in my post or anything else that I said that's wrong/what else am I missing? I've been reviewing metabolic pathways a lot in the books I have, so if there's anything else you think I may be missing I'll definitely do some research on it.

Honestly, I think you're doing great. What I meant by you're getting confused is that the complexity of biochemistry can be overwhelming at times. Just keep on studying from your books, and keep asking yourself questions. The easiest way to learn something is to understand as opposed to simply memorizing it, and you seem to be able to integrate different concepts quite well.