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when glucose is high in diabetics what happends to the activy of glycogen synthase? WHy?

when glucose is high in diabetics what happends to the activy of glycogen synthase? WHy?

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Expert Solution

Glycogen synthase (GS) is inactive in diabetics.

GS activity depends on the activity of enzymes GSK3 (kinase that activates phosphorylation of 3 serine residues of GS and inactivates GS) and PP1 (Phosphatase enzyme which activates GS by dephosphorylation). The regulation of GS activity is purely hormonal. The other type regulation is allosteric by glucose 6 phosphate.

Insulin activates PP1 and inhibits GSK 3 by inhibiting cAMP thus activates GS in normal persons by activating glucose transpoters on cell membrane and also by activating GS.

But in Diabetic condition due to the defect in insulin production /activity , the activation of GS is impaired. Glucose transport into cell is also decreased. So it can be concluded that GS activity reduced in insulin resisntance in muscle and liver cells.

gladiator answered 1 year ago
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