Chenodeoxycholic acid therapy in erythrohepatic protoporphyria

Area of Science:

• Biochemistry
• Hepatology
• Clinical Medicine

Background:

• Erythropoietic protoporphyria (EPP) is a rare genetic disorder characterized by increased protoporphyrin accumulation.
• Current management strategies for EPP focus on symptom alleviation and photoprotection.
• Understanding the metabolic pathways of protoporphyrin is crucial for developing targeted therapies.

Purpose of the Study:

• To investigate the short-term effects of chenodeoxycholic acid (CDCA) on protoporphyrin excretion and levels in patients with EPP.
• To assess the impact of CDCA administration on hepatic protoporphyrin production.

Main Methods:

• A short-term study involving 5 patients diagnosed with erythrohepatic protoporphyria.
• Daily collection of faeces and bile, with blood sampling every 2-3 days.
• Administration of chenodeoxycholic acid at 15 mg/kg/day, followed by continued sample collection and analysis of protoporphyrin concentrations using high-pressure liquid chromatography and fluorometry.

Main Results:

• Significant reduction in protoporphyrin concentration in faeces and bile after CDCA administration.
• All patients exhibited a significant decrease in erythrocyte protoporphyrin levels.
• CDCA treatment led to a marked decrease in overall protoporphyrin excretion.

Conclusions:

• Chenodeoxycholic acid therapy effectively reduces protoporphyrin excretion in patients with erythrohepatic protoporphyria.
• The observed decrease in erythrocyte protoporphyrin suggests that CDCA may inhibit protoporphyrin production in the liver.
• CDCA shows potential as a therapeutic agent for managing protoporphyrin accumulation in EPP.