Glycylprolyl beta-naphthylamidase activity in human serum

Area of Science:

• Biochemistry
• Clinical Chemistry

Background:

• Glycylprolyl beta-naphthylamidase is an enzyme found in human serum.
• Understanding its activity and variations is crucial for diagnostic purposes.

Purpose of the Study:

• To investigate the activity of glycylprolyl beta-naphthylamidase in normal individuals.
• To determine the enzyme's activity in relation to age, sex, and specific diseases.
• To explore the enzyme's electrophoretic behavior in various serum conditions.

Main Methods:

• Serum samples from 40 normal subjects were analyzed for enzyme activity at 37°C.
• Activity levels were compared between age groups (under and over 40) and sexes.
• Enzyme activity was assessed in patients with gastric cancer and hepatobiliary diseases.
• Cellulose acetate electrophoresis was performed on normal and diseased sera.

Main Results:

• Normal serum glycylprolyl beta-naphthylamidase activity was 22.6 +/- 0.9 I.U./L.
• Activity did not significantly differ with age but was higher in males, particularly those under 40.
• Enzyme levels were decreased in gastric cancer patients and elevated in hepatobiliary disease patients.
• Significant correlations were observed between enzyme activity and markers of hepatic disease (AST, ALT, ALP, bilirubin), but not LDH.
• Electrophoresis showed a single beta-globulin peak in normal sera, with additional alpha1 and alpha2-globulin peaks in hepatitis and liver cirrhosis.

Conclusions:

• Serum glycylprolyl beta-naphthylamidase activity is influenced by sex and is a potential biomarker for gastric cancer and hepatobiliary diseases.
• Electrophoretic analysis of this enzyme may aid in diagnosing liver conditions like hepatitis and cirrhosis.