S. Teno et al., Increased activity of membrane glycoprotein PC-1 in the fibroblasts from non-insulin-dependent diabetes mellitus patients with insulin resistance, DIABET RE C, 45(1), 1999, pp. 25-30
Although most of patients with non-insulin-dependent diabetes mellitus (NID
DM) have insulin resistance, it is unknown whether a molecule might interfe
re with insulin action. Membrane glycoprotein PC-1 (plasma cell antigen-1),
which inhibits insulin receptor tyrosine kinase activity, was isolated fro
m fibroblasts of NIDDM patients. Because PC-I content in skeletal muscle an
d adipose tissue correlated with whole body insulin sensitivity, PC-I might
play a role in insulin resistance. In order to know whether PC-1 activity
of fibroblasts is also elevated in Japanese NIDDM patients, and whether PC-
1 activity correlates with the parameters of insulin resistance in vivo or
not, we measured PC-1 activity of cultured fibroblasts from 17 patients wit
h NIDDM and seven healthy controls. PC-1 activity of the NIDDM patients was
85.2 +/- 33.1 nmol/mg per min (mean +/- S.D.), and was higher than that of
healthy controls (42.6 +/- 12.7 nmol/mg per min, P = 0.0002). Insulin sens
itivity was measured in 11 of 17 NIDDM patients by the artificial pancreas.
PC-1 activity of the patients with insulin resistance (glucose infusion ra
te < 3.0 mg/kg per min, n = 7) was elevated to 99.9 +/- 31.9 nmol/mg per mi
n, while that of the other patients (n = 4) was 55.3 +/- 7.5 nmol/mg per mi
n (P = 0.003). In conclusion, glycoprotein PC-1 activity of dermal fibrobla
sts is correlated with insulin resistance in patients with NIDDM. (C) 1999
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