Aldolase B deficiency

Fnictokinase Defidenc)r (Essoitial Fnictosuria) Fructose l-Phoq>hate Aldolase (Aldolase B) Deficiency (Hereditary Iroctose Intolerance)... 

Hereditary fructose intolerance is due to aldolase B deficiency and is often diagnosed when babies are switched from formula or mother s milk to a diet containing fructose-based sweetening, such as sucrose or honey. 

Aldolase B. Deficiency of aldolase B causes hereditary fructose intolerance (Chapter 22). Aldolase B occurs in the liver, kidney and small intestine. 

Deficiency of aldolase B, although this isozyme is not expressed in red blood cells, is responsible for hereditary fructose intolerance, an autosomal recessive dis-... 

Cause and treatment of hereditary fructose intolerance A deficiency of fructokinase causes a benign condition, but a deficiency of aldolase B causes hereditary fructose intolerance, in which severe hypoglycemia and liver damage can lead to death if the amount of fructose (and, therefore, sucrose) in the diet are not severely limited. 

Individuals with a deficiency in aldolase B have the condition known as fructose intolerance. As with most enzyme deficiencies, this is an autosomal recessive disease it does not cause difficulty as long as the patient does not consume any foods with fructose or sucrose. Frequently, children with fructose intolerance avoid candy and fruit, which should raise some eyebrows Likewise, they usually do not have many dental caries. However, if chronically exposed to fractose-containing foods, infants and small children may have poor weight gain and abdominal cramping or vomiting. 

Fructose intolerance A genetic deficiency in the liver enzyme aldolase B. The absence of this enzyme leads to a build up of fructose 1-phosphate and depletion of liver ATP and phosphate stores. 

In the liver, kidney, and intestine, fructose can be converted to glycolytic/ gluconeogenic intermediates by the actions of three enzymes—fructokinase, aldolase B, and triokinase (also called triose kinase)—as shovra in Figure 24-1. In these tissues, fructose is rapidly phosphorylated to fructose 1-phosphate (FIP) by fructokinase at the expense of a molecule of adenosine triphosphate (ATP). This has the effect of trapping fructose inside the cell. A deficiency in this enzyme leads to the rare but benign condition known as essential fmcto-suria. In other tissues such as muscle, adipose, and red blood cells, hexokinase can phosphorylate fructose to the glycolytic intermediate fmctose 6-phosphate (F6P). 

The toxic effects of FIP can also be exhibited in patients that do not have a deficiency in aldolase B if they are parenterally fed with solutions containing fructose. Parenteral feeding with solutions containing fructose can result in blood fructose concentrations that are several times higher than can be achieved with an oral load. Since the rate of entry into the hepatocyte is dependent on the fructose gradient across the cell, intravenous loading results in increased entry into the liver and increased formation of FIP. Since the rate of formation of FIP is much faster than its further metabolism, this can lead to hyperuricemia and hyperuricosuria by the mechanisms described above. 

A deficiency in aldolase B leads to the condition known as fructose intolerance. 

Essential fructosuria is a rare and benign genetic disorder caused by a deficiency of the enzyme fructok-inase. Why is this disease benign, when a deficiency of aldolase B (hereditary fructose intolerance) can be fatal Could Candice Sucher have essential fructosuria ... 

Pyruvate dehydrogenase complex deficiency Hereditary fructose Aldolase B intolerance... 

Volk, B. W., S. M. Aronson, and A. Saifer Fructose-1-phosphate aldolase deficiency in Tay-Sachs disease. Amer. J. Med. 36, 481 (1964). 

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