Pravastatin induces NO synthesis by enhancing microsomal arginine uptake in healthy and preeclamptic placentas

Abstract

BackgroundPravastatin, a known inducer of endothelial nitric-oxide synthase (eNOS) was demonstrated in human placenta, however the exact mechanism of it’s action is not fully understood. Since placental NO (nitric oxide) synthesis is of primary importance in the regulation of placental blood flow, we aimed to clarify the effects of pravastatin on healthy (n = 6) and preeclamptic (n = 6) placentas (Caucasian participants).MethodsThe eNOS activity of human placental microsomes was determined by the conversion rate of C14 L-arginine into C14 L-citrulline with or without pravastatin and Geldanamycin. Phosphorylation of eNOS (Ser1177) was investigated by Western blot. Microsomal arginine uptake was measured by a rapid filtration method.ResultsPravastatin significantly increased total eNOS activity in healthy (28%, p<0.05) and preeclamptic placentas (32%, p<0.05) using 1 mM Ca2+ promoting the dissociation of a eNOS from it’s inhibitor caveolin. Pravastatin and Geldanamycin (Hsp90 inhibitor) cotreatment increased microsomal eNOS activity. Pravastatin treatment had no significant effects on Ser1177 phosphorylation of eNOS in either healthy or preeclamptic placentas. Pravastatin induced arginine uptake of placental microsomes in both healthy (38%, p < 0.05) and preeclamptic pregnancies (34%, p < 0.05).ConclusionsThis study provides a novel mechanism of pravastatin action on placental NO metabolism. Pravastatin induces the placental microsomal arginine uptake leading to the rapid activation of eNOS independently of Ser1177 phosphorylation. These new findings may contribute to better understanding of preeclampsia and may also have a clinical relevance.

Pravastatin‐induced changes in expression of long non‐coding and coding RNAs in endothelial cells

“…Using a dose of 10 μM pravastatin (Abe et al., 2006; Panczel et al., 2019), we were able to profile all differentially expressed mRNAs and lncRNAs in human ECs in vitro . A total of 181 lncRNAs and 280 mRNAs were significantly differentially expressed in pravastatin‐treated versus control ECs (log 2‐fold > 2, adjusted p < .05).…”

“…However, to our knowledge, this is the first study highlighting the differential expression of endothelial lncRNAs and mRNAs following statin treatment. Using a dose of 10 μM pravastatin (Abe et al, 2006;Panczel et al, 2019), we were able to profile all differentially expressed mRNAs and lncRNAs in human ECs in vitro. A total of 181 lncRNAs and 280 mRNAs were significantly differentially expressed in pravastatin-treated versus control ECs (log 2-fold > 2, adjusted p < .05).…”

“…Passage 4–6 HUVECs were used for the experiments. Cells were (60%–70%) confluent and were starved over‐night in MCDB‐131 basal medium with 1% FBS, followed by treatment with pravastatin sodium salt hydrate (10 µM; Sigma) (Abe et al., 2006; Panczel et al., 2019) in the same MCDB‐131 basal medium with 1% FBS for 24 hr. Controls were treated with vehicle phosphate‐buffered saline.…”

A pravasztatin hatása tetrahidrobiopterin-érzékeny és -rezisztens praeeclampsiás placenták NO-szintáz-aktivitására

“…Korábbi munkánkban kimutattuk, hogy a pravasztatin gyorsan is képes expressziótól és foszforilációtól függetlenül a humán placenta NOS-aktivitását növelni. A hatás azon alapszik, hogy a pravasztatin növeli a NOS szubsztrátjának, az argininnak a felvételi sebességét, így az enzim argininellátottsága javul [9]. Praeeclampsiás terhességben megfigyelték, hogy csökkenhet a szérum argininszintje, ami hozzájárulhat a NOS-aktivitás csökkenéséhez, és emelheti az oxidatív stresszt [25].…”

“…A placebocsoport 40%-ánál praeeclampsia alakult ki, míg a pravasztatinos csoportban nem volt praeeclampsiás eset [7]. [8], emiatt késlekedés nélkül mikroszómát preparáltunk belőle a már közölt módon [9]. A mikroszóma-frakcióból fehérjemeghatározásra mintákat különítettünk el, majd legalább három részre osztva a mintákat -80 °C-on tároltuk felhasználásig.…”