Preeclampsia and phototherapy
Authors: Griffin Jakara , Krolikowski John G. , Kounga Kenisha , Keszler Agnes , Lohr Nicole , Weihrauch Dorothee 
Published: April 2020

Preeclampsia is a leading cause of maternal morbidity and mortality worldwide, complicating 2–8% of pregnancies, and is recognized as an independent risk factor for CVD by the ACC/AHA. The etiology of preeclampsia is poorly understood. However, the role of placental extracellular matrix (pECM) and extravillous trophoblast in placental blood vessel formation and preeclampsia is understood.

The objective is to identify phenotypical changes in extravillous trophoblast (HTR8/SVneo) in a preeclampsia microenvironment using healthy and preeclamptic patient placental samples vs Dahl S rats (SS) as an animal model of superimposed preeclampsia and explore a novel therapeutic modality restoring trophoblastic phenotype by phototherapy using a 670nm light (NIR).

Placentas from rats and patients were decellularized and characterized using pECM markers galectin‐3 and heparan sulfate proteoglycan 2 (HSP2) by western blot and immunofluorescence. pECM was used as substrate for HTR8/SVneo. Proliferation, migration, and apoptosis assays were used to determine cell behavior in the placental microenvironment. Immunofluorescence for placental growth factor (PLGF) and transforming growth factor (TGFβ) was performed on HTR8/SVneo cultured on both pECM. NIR was applied to HTR8/SVneo cultured on patient and rat pECM with 4J/cm2 intensity.

In patient samples galectin‐3 expression was reduced by 34.21%±13.16 in preeclamptic PE compared to control patient pECM. HSP2 was reduced by 14.75%±6.11 in PE compared to control patient pECM. In rats galectin‐3 expression was reduced to 51.58%±3.78 in SS compared to control rat pECM. HSP2 was reduced to 45.15%± 0.63 in SS compared to control rat pECM.

Migration of HTR8/SVneo on pECM (patient: control 11.08±0.82, PE 6.45±0.88; rats: control 3.87±0.96, SS 4.42±1.18) and proliferation of HTR8/SVneo on pECM were decreased in patients (# of cells X 1000) control: 59.125±6262.9, PE:67.125±7706.5 and rat control 5.16±0.79, SS 4.25±0.6 samples. Proliferation and migration were restored by NIR treatment: proliferation patient: control 101.375±2075.4; PE 106.875±4870.7, migration rat: control 12.58±7.06, SS 5.11±2.55. An increased number of apoptotic HTR8/SVneo was observed in preeclamptic pECM compared to healthy pECM: patient control 2.4±0.24, PE 3±0.4 and rat apoptotic cells control 5.2±0.89; SS 7.4±1.23). NIR decreased the number of apoptotic cells, patient:1.2 ±0.58, PE 1.4±0.5; rat control 3.9±0.43, SS 5.4±0.73.

PLGF and TGFβ were downregulated in HTR8/SVneo when cultured on preeclamptic pECM from patients compared to healthy pECM and unchanged in rats. Fluorescence Intensity of PLGF in patient pECM; control 102.12±14.91, PE 68.77±9.73, TGFβ control 88.86±2.51, PE 63.59±4.83 and rats; PLGF control 65.18±0.79, SS 61.09±0.68; TGFβ control 60.78±0.48, SS 61.47 ± 0.45. The decrease was reversed by NIR treatment in patients; PLGF control 165.05±12.32, PE 175.14±12.48, TGFβ control 74.99±7.17, PE 91.03±2.27; rat PLGF control 66.58±0.99, SS 65.57±1.52, TGFβ control 66.67±1.58, SS 63.82±1.53).

Extracellular matrix is altered in preeclampsia, and HTR8/SVneo trophoblasts respond similarly to altered matrix in preeclamptic placentas from patients and rats. 670nm light application restored the phenotype of HTR8/SVneo on preeclamptic pECM in patients and rats suggesting NIR as a therapeutic.