Enzymatic changes in polymorphonuclear cells isolated from type II diabetics.
The absolute values of several enzymes present in polymorphonuclear (PMN) cells isolated from subjects catalogued as Type II diabetics that never received insulin to control their hyperglycemia are reported. PMN from the blood of fasting diabetics and a control group were isolated by the dextran flotation technique. The enzymes were assayed in whole homogenates prepared by sonication of the cells. Serum glucose and immunoreactive insulin (IRI) were also determined from the same blood sample. We found a 40% decrease in the levels of phosphofructokinase (39.7 +/- 3.0 vs 66.1 +/- 6.3 mU/mg, P less than 0.001) and lactate dehydrogenase (350 +/- 22 vs 583 +/- 49 mU/mg, P less than 0.001) and a 25% decrease in malate dehydrogenase (250 +/- 29 vs 341 +/- 20 mU/mg, P less than 0.01). No differences in hexokinase (16.3 +/- 1.7 vs 18.2 +/- 1.7 mU/mg, P greater than 0.1) and glucose-6-phosphate dehydrogenase (66.6 +/- 2.5 vs 76.3 +/- 5.7 mU/mg, P greater than 0.05) were detected. These patients had normal or elevated levels of IRI (22.9 +/- 2.8 vs 14.5 +/- 2.4 microU/ml, P less than 0.05) concomitant with hyperglycemia (162.7 +/- 10.2 vs 78.0 +/- 1.6 mg/dl, P less than 0.001), revealing some degree of insulin resistance. It appears that glycolysis is affected not only at the phosphofructokinase step but beyond this point, glucose-6-phosphate dehydrogenase is not affected, and defective insulin action more than the lack of insulin might be responsible for the metabolic alteration.
D050260:Carbohydrate Metabolism; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D005954:Glucosephosphate Dehydrogenase / Q000097:blood; D006593:Hexokinase / Q000097:blood; D006943:Hyperglycemia / Q000097:blood; D007328:Insulin / Q000502:physiology; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008291:Malate Dehydrogenase / Q000097:blood; D009504:Neutrophils / Q000201:enzymology*; D010732:Phosphofructokinase-1 / Q000097:blood
D007328:Insulin; D007770:L-Lactate Dehydrogenase; D008291:Malate Dehydrogenase; D005954:Glucosephosphate Dehydrogenase; D006593:Hexokinase; D010732:Phosphofructokinase-1