Einfluss des Körpergewichts auf die enterale Sterolresorption und die endogene Cholesterinsynthese

Zusammenfassung

Neue Erkenntnisse bezüglich der molekularen Regulation des Sterolstoffwechsels sowie neue Marker der Cholesterinhomöostase erlauben heute eine präzisere Beurteilung des komplexen Cholesterinstoffwechsels und seiner Störungen. Erste Untersuchungen ergaben, dass Patienten mit Diabetes mellitus Typ I und Typ II sowie Adipositas charakteristische Veränderungen im Cholesterinstoffwechsel aufweisen. Typ II-Diabetiker und Patienten mit Adipositas zeigen eine verstärkte hepatische Synthese und biliäre Ausscheidung von Cholesterin. Mit Hilfe neuer massenspektrometrischer Methoden lassen sich Phytosterole als Marker der enteralen Sterolresorption und Lanosterol als Marker der endogenen Cholesterinresorption im Hochdurchsatz präzise analysieren. Dies ermöglicht erstmals eine Analyse des Cholesterinstoffwechsels in großen Populationsstudien. Erste Ergebnisse zeigen dass die Höhe des BMI unabhängig von anderen Risikofaktoren für das metabolische Syndrom positiv mit der Cholesterinsynthese korreliert. Diese Befunde müssen nun weiter analysiert werden, insbesondere der Einfluss fettgewebsassoziierter Faktoren und Hormone auf den Cholesterinstoffwechsel. Das verbesserte Verständnis des Cholesterinstoffwechsels sowie seiner Störungen im Rahmen von Adipositas und Diabetes mellitus wird die Möglichkeit einer differenzierten Diagnostik und Therapie eröffnen.

Summary

New findings regarding the cellular and molecular regulation of the sterol metabolism and new markers of the cholesterol homeostasis allow today a precise determination of the complex cholesterol metabolism and its disturbances. First investigations revealed, that patients suffering from type I diabetes, type II diabetes and obesity have characteristic changes in the cholesterol metabolism. In type II diabetes patients and obese persons the endogenous sterol synthesis and biliary excretion of cholesterol were increased in and the body mass index was positive correlated to endogenous cholesterol synthesis. New mass spectrometry methods for analyzing phytosterols as markers of intestinal sterol absorption and lanosterol as a marker of endogenous sterol synthesis facilitate the substantial analysis of the cholesterol metabolism in population-wide studies. First results show a positive association between elevated BMI and increased cholesterol synthesis independent from other risk factors of the metabolic syndrome. These primarily results have to be further analyzed. Especially, the influences of adipose tissue-related factors and hormones on cholesterol metabolism have to be further investigated. The understanding of the cholesterol metabolism and its disturbances, especially in patients suffering from metabolic diseases, will open up new opportunities for a differential diagnosis and therapy.

Schlüsselwörter

Cholesterinstoffwechsel - Sterolresorption - Cholesterinsynthese - Phytosterole

Keywords

Cholesterol metabolism - sterol resorption - cholesterol synthesis - phytosterols

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