Estradiol counteracts oxidized LDL-induced asymmetric dimethylarginine production by cultured human endothelial cells

Abstract

Estradiol completely reverses the effects induced by oxLDL on the DDAH/ADMA/NO pathway.

Estradiol, acting through estrogen receptor alpha, restores dimethylarginine dimethylaminohydrolase activity and nitric oxide production in oxLDL-treated human arterial endothelial cells

“…Both the unaltered PRMT-1 expression protein profile and the unaltered SDMA levels ruled out this hypothesis. In fact, SDMA remained unaltered when cells were exposed to the different treatments, which is in complete agreement with previous studies performed in HUVEC (Boger et al, 2000;Monsalve et al, 2007).…”

“…These concentrations were chosen based on our previous studies, and were able to modify DDAH/ADMA/NO pathway in other types of endothelial cells (Monsalve et al, 2007). LDL was isolated and pooled from fasting plasma samples from healthy donors (nLDL).…”

“…LDL was isolated and pooled from fasting plasma samples from healthy donors (nLDL). oxLDL was prepared by incubation with 10 lM CuSO 4 (4 h at 37°C) as previously described (Monsalve et al, 2007). The effectiveness of LDL oxidation was assured by measuring malondialdehyde levels in duplicate on the nLDL as well as the oxLDL samples.…”

“…Culture wells were then washed with PBS, and adherent cells were collected in 0.5 N NaOH solution for protein determination by the BCA method (Thermo Scientific Inc., Rockford, IL, USA). Endothelial NO production was determined using the ISONOP nitric oxide sensor (World Precision Instruments, Sarasota, FL, USA) an amperometric sensor specific for NO as described earlier (Monsalve et al, 2007).…”

“…Indeed, experimental evidence suggest that estrogen, particularly the endogenous 17b-estradiol, exerts cardiovascular protection via the promotion of endothelial vasodilator synthesis, including NO production through both increased expression and activity of eNOS (Mendelsohn, 2009) and prostacyclin (Sobrino et al, 2010) as well as through a reduction in endothelial production of ADMA (Holden et al, 2003;Monsalve et al, 2007). These effects are mainly mediated through classical estrogen receptor (ER) a and ERb, which are both expressed in endothelial cells (Sobrino et al, 2010).…”