Kefir peptides mitigate L-NAME-induced preeclampsia in rats through modulating hypertension and endothelial dysfunction.

Aim: Preeclampsia is a complex and serious pregnancy disorder that leads to maternal and neonatal mortality worldwide. Kefir peptides (KPs), derived from various prebiotic fermentations in whole milk by kefir grains, were investigated for their potential therapeutic effects. In this study, we used the L-NAME in drinking water to induce a preeclampsia-like condition in spontaneous hypertension stroke-prone (SHRSP) pregnant rats.

Main methods: The rats were assigned to five groups: the normal group (WKY rats), the untreated group (SHRSP rat control pregnant), the L-NAME/Mock group (SHRSP rats fed with L-NAME water), the L-NAME/KPs-LD group (SHRSP rats fed with L-NAME water and low-dose KPs diets), and the L-NAME/KPs-HD group (SHRSP rats fed with L-NAME water and high-dose KPs diets) for a 20-day experiment. Chorioallantois membrane (CAM) assay was applied for ex vivo angiogenesis study of KPs treatment.

Key findings: Data showed that rats in the L-NAME group developed severe hypertension, proteinuria, placental damage, and embryo resorption. Pre-administration of KPs significantly reduced hypertension, proteinuria, improved generalized endothelial dysfunction, and decreased levels of anti-HIF-1α, sFLT1, anti-TNF-α, and IL-6 in the placenta of SHRSP rats. In ex vivo CAM study, L-NAME administration in chicken embryos resulted in lower vessel density and hemorrhage; however, angiogenesis was observed after KPs-HD treatment.

Significance: The results indicate that kefir peptides improve renal lesions, prevent renal parenchyma damage, and balance endothelial and angiogenic dysfunction in both maternal and fetal sites in L-NAME-induced SHRSP pregnant rats.