Regulation of the pentose cycle
As already stated above, the pentose cycle is regulated at the level of availability of the coenzyme NADP+ . If the result reduced form of NADPH is not pumped out and reoxidized in other metabolic processes, reactions that require the oxidized form of this coenzyme are inhibited. The reduction of NADP+ to NADPH is catalyzed by glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase. The synthesis of key enzymes is also induced by insulin. Prolactin does the same during lactation.
Clinical correlation:
Glucose-6-phosphate dehydrogenase deficiency is considered the most widespread enzymatic defect worldwide - the number of affected is estimated at 400 million people (mainly in Africa, the Mediterranean, the Middle East and Asia). One of its consequences is the development of hemolytic anemia (due to disruption of the antioxidant systems of erythrocytes). You can find more detailed information in the multimedia scripts Functions of cells and the human body, 3. LF UK.
| Transformation of substances and energy in the cell | |
|---|---|
| Nutrient Chemistry | |
| Overview of energy metabolism | |
| Compartmentation of metabolic pathways | |
| What drives our cells | |
| Chemical reactions in metabolism | |
| Enzymes | |
| The respiratory chain and the formation of ATP | |
| Krebs cycle | |
| Breakdown and synthesis of glucose | |
| Pentose cycle, metabolism of fructose, galactose and glucuronic acid | |
| Lipid breakdown and metabolism of ketone bodies | |
| Amino acid metabolism | |
| Energy storage in the human body - glycogen metabolism and the formation of fatty acids and triacylglycerols | |
| Regulation of metabolic pathways at the cell level | |
| Fontana J., Trnka J., Maďa P., Ivák P. et al.: Transformation of substances and energy in the cell. In: Functions of cells and the human body : Multimedia scripts. |
