Changes of Acute-Phase Proteins in Streptozotocin-Induced Diabetic Rats
L. Saso, P. Tommasino, G. Italiano1, E. Grippa, M.G. Leone, M.T.
Gatto, B. Silvestrini
Department of Pharmacology of Natural Substances and General Physiology,
University of Rome, Rome and 1Fidia Research Laboratories, Abano
Terme, Italy
Received July 19, 1999
Accepted January 20, 2000
Summary
Quantitative and qualitative changes of serum proteins, apart
from glycation, have not been sufficiently studied in streptozotocin-induced
diabetic rats (D), the most common experimental model for diabetes. Thus, we
decided to analyze the serum of diabetic rats by concanavalin A-blotting in
comparison with rats with acute inflammation induced by fermented yeast (Y), in
which characteristic alterations of serum proteins have been described. Two
months after the streptozotocin treatment, the blood glucose levels were highly
elevated (456± 24 vs. 124±
10 mg/dl, p<0.001, n=12), the body weight was significantly lower than normal
(279± 10 vs. 392± 6 g,
p<0.001, n=12), and serum proteins appeared to be highly glycated
(p<0.001) when analyzed by the fructosamine assay, without any significant
change in the total serum protein concentration. Analysis by concanavalin
A-blotting, revealed a significant decrease of a1-inhibitor-3
(a1-I3,
p<0.05) and an increase of the b
chain of haptoglobin (b-Hp,
p<0.05) in both D and Y rats (n=3) compared with control animals. However,
acute inflammation caused a marked rise of two prominent acute phase proteins, a2-macroglobulin
and hemopexin, which did not change appreciably in diabetic rats. Further work
will be necessary to evaluate the physiopathological significance of these
phenomena which could result from changes of both concentration and
glycosylation of the aforementioned proteins.
Key words
Streptozotocin · Acute phase
protein(s) · a1-inhibitor-3 · Haptoglobin ·
Glycosylation
Reprint requests
B. Silvestrini, Department of Pharmacology of Natural
Substances and General Physiology, University of Rome ”La Sapienza”, P.le
Aldo Moro 5, 00185 Rome, Italy. Fax: +39-06-49912480, E-mail: silvestrini@uniroma1.it
|