Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:4.1.2.13 (aldolase)
 3,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the differential diagnosis of intermittent claudication some rare myopathies have to be considered. The most frequent is phosphorylase deficiency (McArdle's disease). Exercise-induced muscular pain, weakness, contractures and occasionally myoglobinuria are the most prominent clinical signs. Serum creatine phosphokinase, aldolase and lactic dehydrogenase may be elevated after exertion. In the ischemic forearm test there is no rise of serum lactic acid. The enzyme deficiency can be demonstrated by histochemical and biochemical examination of a muscle specimen. Further, but more infrequent, enzymatic disturbances of glycolysis are phosphofructokinase deficiency and phosphohexoisomerase inhibitor, which also yield an abnormal ischemic forearm test and must be demonstrated histochemically and biochemically. Apart from muscular signs, myopathy with lactic acidosis is associated with palpitation, dyspnea and exhaustion, and a disproportionate rise in serum lactic acid level after exertion. Histochemically and electronmicroscopically demonstrable fat accumulation in the muscle can be a sign of a disturbance in lipid metabolism. This type of exercise-induced myopathy has been reported only in a few cases with carnitine-pylmityltransferase deficiency, which has to be demonstrated biochemically. Muscular contractures also exercise-induced but painless and reversible within seconds may be due to deficient uptake of sarcoplasmic calcium in the tubular system. Dyskalemic paralysis causes painless paresis within minutes of hours after exertion, which disappears within hours to a few days. Myopathy with tubular aggregates can be differentiated from other exercise-induced myopathies by morphology. Myotonia combined with painful contractures characterizes myopathia myotonica.
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PMID:[Exercise-induced muscular weakness, myalgia and contractures. I. A clinical review]. 13 80

An 8-month-old female, maintained on breast feeding for 6 months, experienced numerous attacks of hyperventilation when weaned to baby food and was admitted with severe lactic acidosis (20 mM) and hypoglycemia. Physical examination was negative except for hepatomegaly. Fasting (18 hr) after stabilization on a high carbohydrate diet resulted in hypoglycemia (plasma glucose 40 mg/100 ml), lactic acidosis (6-10 mM), and a rise in plasma alanine. Glucagon produced a glycemic response after 6 hr, but not after 18 hr fasting. Intravenous galactose increased plasma glucose (Delta 45 mg/100 ml) but intravenous fructose, glycerol, and alanine caused a 40-50% fall in plasma glucose and a significant rise in lactate (Delta 3-4 mM). Liver biopsy showed fatty infiltration. Liver slices incubated with galactose, lactate, fructose, alanine, or glycerol converted only galactose to glucose. Hepatic glycolytic intermediates were increased below the level of fructose-1,6-diphosphate and decreased above. Hepatic phosphorylase, glucose-6-phosphatase, amylo-1,6-glucosidase, phosphofructokinase, fructose-1-phosphate aldolase, and fructose-1,6-diphosphate aldolase levels were normal, but no fructose-1,6-diphosphatase (FDPase) activity was detected. Further studies on the liver homogenate of this patient revealed the presence of an acid-precipitable activator of FDPase. Normal plasma glucose and lactate levels were maintained on an 800 cal diet of 66% carbohydrate (sucrose and fructose excluded). 5% protein, and 20% fat. When carbohydrate was reduced to 35% and protein or fat increased to 23 and 53% respectively, lactic acidosis and hypoglycemia recurred. These studies show that a deficiency of FDPase produced infantile lactic acidosis and hypoglycemia and can be controlled by an appropriate diet.
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PMID:Hepatic fructose-1,6-diphosphatase deficiency. A cause of lactic acidosis and hypoglycemia in infancy. 434 Oct 15

In experiments on mongrel albino male rats, we studied the effects of 30 mmol/kg lactic acid, 30 mmol/kg NaHCO3, and 20 mmol/kg NH4Cl (intraventricular injections, daily for 7 days) on the contents of total protein, residual nitrogen, urea, and creatinine in the blood, as well as on the activities of aldolase and alanine aminotranspherase (ALT). We also studied the effects of the above agents on renal functions: glomerular filtration rate (GFR), diuresis, and excretion of ammonium, creatinine, and protein with urine. We have found that chronic, hyperchloremic, and lactic acidosis resulted both in a significant decrease in the levels of protein and residual nitrogen and in an increase in the concentration of the urea; these phenomena were accompanied by a considerable intensification of the urinary NH4+ excretion. In contrast, under conditions of chronic alkalosis we observed a drop in the level of urea in the blood with no changes in the concentrations of protein and residual nitrogen, as well as a dramatic depression of the urinary NH4+ excretion. In that case, the concentration of creatinine in the blood, GFR, diuresis, and excretion of creatinine and protein with urine did not correlate with the above-mentioned changes in protein metabolism. In all experiments, the activities of aldolase and ALT preserved their normal level giving evidence against damage to the liver. These results give evidence for spending a great number of amino acids on the renal ammoniogenesis at chronical acidosis; their saving at alkalosis; an impairment of the protein synthesis, and an increase in protein catabolism at acidosis to replenish the pool of amino acids, as well as for an activation of the urea synthesis to eliminate the excessive amount of NH4+ from the blood.
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PMID:[Effect of chronic acidosis on protein metabolism]. 1466 91

Since 1967, fructose has become the primary commercial sweetener in the food industry. Large amounts of fructose can be toxic and have been correlated with atherosclerosis, malabsorption, hyperuricemia, lactic acidosis, and cataracts. To understand the deleterious and critical role(s) fructose plays in normal metabolism, it is essential to know how and where fructose is metabolized. The fructose transporter, GLUT5, and the specialized enzymes ketohexokinase, aldolase, and triokinase comprise the well-defined fructose-specific metabolic pathway found in liver, kidney, and small intestine. It is estimated that 50-70% of ingested fructose is metabolized in these tissues; where and how the remaining 30-50% is metabolized is not well defined. Prediction of tissues capable of metabolizing fructose via this pathway was done using expressed sequence tags (ESTs) in Unigene and a gene-specific virtual northern blot (VNB) algorithm. Unigene and VNB combined correctly predicted the expression of the genes required for fructose metabolism in liver, kidney, and small intestine. Both methods indicated brain, breast, lymphocytes, muscle, placenta, and stomach additionally express this set of genes. Expression of the genes for GLUT5 (glut5) and ketohexokinase (khk) in neurons was validated by immunohistochemistry and RNA in situ hybridization, respectively. Using stringent controls, clear expression of glut5 and khk was localized to Purkinje cells in the cerebellum. Cerebellum was used to oxidize fructose to carbon dioxide. Together, these data suggest that these neurons in the brain are able to utilize fructose as a carbon source.
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PMID:Genes required for fructose metabolism are expressed in Purkinje cells in the cerebellum. 1626 70