Untersuchungen des maternalen und fetalen Serumlipidprofils und des oxidierten ‚Low Density‘ Lipoproteins im plazentaren Gewebe bei Präeklampsie und normotensiven Schwangerschaften

Zusammenfassung

Hintergrund:

Oxidierte ‚Low Density‘ Lipoproteine (oxLDL) gelten als Schlüsselmoleküle in der Pathogenese der Atherosklerose. Da die Prä­eklampsie Parallelen zur Atherosklerose aufweist, gingen wir von der Hypothese einer vermehrten Anreicherung von oxLDL im plazentaren Gewebe an der materno-fetalen und feto-fetalen Grenzfläche aus. Zudem analysierten wir das Lipidprofil des mütterliches und fetales Serums bei Präeklampsie und einer Kontrollgruppe normotensiver Schwangerschaften.

Patientinnen und Methodik:

oxLDL wurde in plazentaren Paraffinschnitten von 14 Präeklampsien (30.–39. SSW) sowie 28 Früh- und Termingeburten (25.–40. SSW) immunhistochemisch dargestellt. 10 ‚High Power Fields‘ wurden mit der newCAST Software randomisiert ausgewählt und nach standardisiertem Verfahren von 2 unabhängigen Untersuchern ohne Kenntnis der ­Diagnosen auf die Intensität von oxLDL bewertet. Triglyzeride, Gesamt-Cholesterin, LDL- und HDL-Cholesterin wurden in mütterlichem und fetalem (Nabelschnur) Serum gemessen. Die statistische Auswertung erfolgte durch den Mann-Whitney Test.

Ergebnis:

oxLDL war sowohl im villösen Trophoblast als auch in plazentaren Endothelzellen nachweisbar. Immunhistochemisch ließen sich keine signifikanten Unterschiede in der oxLDL-Intensität in den verschiedenen Kompartimenten der Patientinnen mit Präeklampsie und unkomplizierter Schwangerschaft nachweisen. Die Serum-Triglyzeridkonzentrationen waren sowohl bei den Müttern als auch bei den Kindern nach Präeklampsie signifikant erhöht (Mutter Präeklampsie 293 [St.abw. 87,4] mg/dL, Kontrolle 214 [Stabw. 89,4] mg/dL, p=0,0097; Fet Prä­eklampsie 26 [St.abw. 16,6] mg/dL, Kontrolle 18 [Stabw. 10,4] mg/dL, p=0,0463). Hinsichtlich der anderen Serumparameter zeigten sich keine signifikanten Unterschiede.

Schlussfolgerung:

Unsere Hypothese einer vermehrten oxLDL Anreicherung im plazentaren Gewebe bei Präeklampsie im Vergleich zu unkomplizierten Schwangerschaften ließ sich nicht bestätigen. Wir fanden allerdings signifikante Unterschiede hinsichtlich der Triglyzeridkonzentration bei Mutter und Kind zwischen Präeklampsie und normotensivem Schwangerschaftsverlauf. Diese Untersuchungsergebnisse bieten Ansatzpunkte für weitere Studien im Rahmen der Entstehung und Programmierung kardiovaskulärer Erkrankungen bei Mutter und Kind.

Abstract

Background:

Oxidised low density lipoproteins (oxLDL) are key players in the development of atherosclerotic cardiovascular diseases. Since there are similarities between the pathogenesis of preeclampsia and atherosclerosis we hypothesised an increased accumulation of oxLDL at the materno-foetal and foeto-foetal interface within the placental tissue of preeclamptic women compared to women with normotensive pregnancies (controls). Moreover, we analysed maternal and foetal serum lipid parameters.

Patients and Methods:

oxLDL was determined by immunohistochemistry in placental paraffin sections of 14 women suffering from preeclampsia (30^th–39^th week of gestation) and compared to 28 preterm and term deliveries (25^th–40^th week of gestation). 10 high power fields were chosen randomly by the newCAST software and oxLDL expression was analysed via standardised methods by 2 independent and blinded investigators. Maternal and foetal triglycerides, total cholesterol, LDL cholesterol and HDL cholesterol were measured. Statistical examination was carried out by the Mann-Whitney test.

Results:

oxLDL was found in villous trophoblast and placental endothelium. No significant differences were observed in expression intensity between preeclampsia and controls. Maternal and foetal triglyceride levels were significantly increased in preeclampsia compared to controls (pre­eclampsia mothers: 293 [SD 87.4] mg/dL, con­trols: 214 [SD 89.4] mg/dL, p=0.0097; preeclampsia foetuses: 26 [SD 16.6] mg/dL, controls: 18 [SD 10.4] mg/dL, p=0.0463). No significant differences in other lipid concentrations were found.

Conclusions:

We could not confirm our initial hypothesis of an increased oxLDL accumulation in placental tissue of preeclampsia. However, preeclampsia is a condition of dyslipidaemia affecting both maternal and foetal serum with implications for development and programming of cardiovascular diseases in later life.

Schlüsselwörter

oxLDL - Plazenta - Präeklampsie - Lipoproteine

Key words

oxLDL - placenta - preeclampsia - lipoproteins

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