Esterolytic activity of blood serum in infants with hypertrophic pyloric stenosis

Area of Science:

• Biochemistry
• Pediatric Gastroenterology
• Enzymology

Background:

• Hypertrophic pyloric stenosis (HPS) is a common infant condition affecting the stomach outlet.
• Serum esterase activity, particularly arylesterase, may play a role in HPS pathogenesis.
• Understanding enzyme kinetics in HPS is crucial for diagnostic and therapeutic insights.

Purpose of the Study:

• To investigate and compare serum esterolytic activity in infants with HPS versus healthy controls.
• To determine the specific esterase substrates most affected in infants diagnosed with HPS.
• To elucidate the role of arylesterase in the physiological changes associated with hypertrophic pyloric stenosis.

Main Methods:

• Serum samples were collected from infants diagnosed with HPS and from a healthy control group.
• The hydrolysis rates of p-nitrophenyl esters of acetic, propionic, and butyric acid were measured.
• Enzyme kinetics were analyzed to quantify esterolytic activity using specific substrates for arylesterase (EC. 3.1.1.2).

Main Results:

• Infants with HPS exhibited significantly higher hydrolysis rates for p-nitrophenyl propionate compared to acetate and butyrate.
• In healthy control infants, hydrolysis rates for all three substrates were similar.
• The overall esterolytic activity, particularly for propionate, was significantly elevated in the HPS group compared to controls.

Conclusions:

• Serum arylesterase activity is significantly altered in infants with hypertrophic pyloric stenosis.
• The preferential hydrolysis of p-nitrophenyl propionate suggests a specific enzymatic change associated with HPS.
• These findings may offer potential biomarkers for diagnosing or understanding the pathophysiology of HPS.