HMP shunt

The hexose monophosphate pathway has several names just to confuse you. It s called the hexose monophosphate shunt or pathway (HMP shunt or pathway), or the pentose phosphate pathway, or the phospho-gluconate pathway (Fig. 15-1). The pathway in its full form is complicated and has complicated stoichiometry. Usually it s not necessary to remember all of it. The important points are that it makes NADPH for biosynthesis and riboses (C-5 sugars) for DNA and RNA synthesis. 

Transketolase HMP shunt Korsakoff (confebulation, psychosis) High-output cardiac failure (wet beri-beri)... 

Answer E. Most important TPP-dependent enzymes include pyruvate dehydrogenase, a-keto-glutarate dehydrogenase, and transketolase. Transketolase is in the HMP shunt and is not strictly essential for glucose oxidation. 

The hexose monophosphate (HMP) shunt (pentose phosphate pathway) occurs in the cytoplasm of all cells, where it serves two major functions ... 

In the cytoplasm, citrate lyase splits citrate back into acetyl CoA and oxaloacetate. The oxaloacetate returns to the mitochondria to transport additional acetyl CoA. This process is shown in Figure I-15-I and includes the important malic enzyme. This reaction represents an additional source of cytoplasmic NAD PH in liver and adipose tissue, supplementing that from the HMP shunt. 

Cholesterol is required for membrane synthesis, steroid synthesis, and in the liver, bile acid synthesis. Most cells derive their cholesterol from LDL or HDL, but some cholesterol may be synthesized de novo. Most de novo synthesis occurs in the liver, vfhere cholesterol is synthesized from acetyl CoA in the cytoplasm. The citrate shutde carries mitochondrial acetyl CoA into the cytoplasm, and NADPH is provided by the HMP shunt and malic enzyme. Important points are noted in Figure 1-15-9,... 

BCNU 1,3-bis(2-chloroethyl)-1 - HMP shunt hexose monophosphate shunt... 

Exposure of various cells to ROIs (H2O2, OC1-) in vitro causes a multitude of biochemical alterations including (a) loss of intracellular ATP and NAD+, (b) stimulation of HMP shunt activity, (c) DNA strand breakage, (d) increase in oxidized protein thiol groups, (e) increase in intracellular Ca2+, (f) activation of poly(ADP-ribose) polymerase, (g) alterations in cell morphology, (h) inhibition of many biosynthetic pathways, (i) 51Cr release, (j) intracellular enzyme... 

GLYCOLYSIS HMP SHUNT PROTEIN SYNTHESIS FATTY ACID SYNTHESIS PART OF UREA CYCLE PART OF... 

Fatty acid synthesis Gluconeogenesis Heme synthesis HMP shunt... 

Since red blood cells do not contain mitochondria, they have no Krebs cycle the main hallway (glycolysis) section does, however, function to produce some of the energy in red blood cells, in addition to the HMP shunt (to be discussed in Carbohydrateiand). 

The DNA Funhouse. Ribose from the HMP shunt provides the sugar group that is part of purine and pyrimidine nucleotides. 

As red blood cells do not have mitochondria or a Krebs cycle, their energy is derived from glycolysis (ATP production) and from the HMP shunt (NADPH production). Defects either in glycolysis or in the HMP shunt may result in red ceU abnorm ities. Sometimes the defect centers in red blood cells. In other cases, it is more generalized. as glycolysis and the HMP shunt are generalized processes. Conditions that affect glycolysis or the HMP shunt include conditions 1-10). 

The series of cytoplasmic reactions known as the pentose phosphate pathway is also called the hexose monophosphate (HMP) shunt (or cycle) or the phosphogluconate pathway. The qualitative interconversions that take place... 

In addition, two patients with recurrent bacterial infections ingested opsonized and nonopsonized particles, but only IgG-coated latex induced the stimulation of O2 consumption, Oi formation, H2O2 production, and HMP shunt activity (W3). The turning on of the metabolic stimulation would then depend on the nature of the stimulus, which could modulate a variable membrane perturbation [the ingestion of very small particles (0.088 fim diameter) have been shown to be accompanied by no change in the resting oxygen uptake (R3)]. 

No situation has been reported in which the existence of stimulated oxygen metabolites was observed without increased oxygen consumption on the contrary, it has been found (T3) that latex particles failed to stimulate superoxide production alone, although the responses of O2 consumption, H2O2 production, and the HMP shunt were similar to these initiated by opsonized zymosan. 

A variety of pharmacological agents have been investigated. The administration of corticosteroids is usually associated with enhancement of infections. It was found that bactericidal activity and HMP shunt activity of leukocytes were depressed following ACTH administration, whereas the glycolytic activity was not altered (S2). As a concomitant, increased... 

The pentose phosphate pathway is also called the hexose monophosphate shunt (HMP shunt). It shunts hexoses from glycolysis, forming pentoses, which may be reconverted to glycolytic intermediates. 

The polyol pathway of sorbitol production and the HMP shunt pathway are linked by which of the following ... 

A) The HMP shunt produces 6-phosphogluconate, an intermediate in the polyol pathway. 

Rossi et al., 1972). As described in figure 1, there is an increase in glucose metabolism via the dehydrogenases of the hexose monophosphate (HMP) shunt, as well as ein increase in the non-mitochondrial consiomption of (Rossi et al.,... 

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