Interactions of two neurosteroids, inhibiting membrane-bound N-Methyl-d-aspartate receptors, with phospholipid membranes are studied. Namely, endogenous pregnanolone sulfate is compared with pregnanolone glutamate, the latter being a novel synthetic steroidal inhibitor of these receptors with potential pharmaceutical use. Molecular-level details of steroid-phospholipid membranes interactions are scrutinized employing molecular dynamics simulations supported by quantum chemical calculations to assess steroid lipophilicity. Moreover, permeability of both species across membranes is experimentally evaluated by immobilized artificial membrane chromatography. We demonstrate that while there is no significant difference of lipophilicity and membrane permeability between the two steroids, they differ significantly regarding detailed localization in phospholipid membranes. The bulky glutamate moiety of pregnanolone glutamate is flexible and well exposed to the water phase while the sulfate group of pregnanolone sulfate is hidden in the membrane headgroup region. This dissimilarity of behavior in membranes can potentially account for the observed different activities of the two steroids toward membrane-bound N-Methyl-d-aspartate receptors.
Herein, we report a new class of amide-based inhibitors (1-4) of N-methyl-d-aspartate receptors (NMDARs) that were prepared as analogues of pregnanolone sulfate (PAS) and pregnanolone glutamate (PAG) - the steroidal neuroprotective NMDAR inhibitors. A series of experiments were conducted to evaluate their physicochemical and biological properties: (i) the inhibitory effect of compounds 3 and 4 on NMDARs was significantly improved (IC50=1.0 and 1.4μM, respectively) as compared with endogenous inhibitor - pregnanolone sulfate (IC50=24.6μM) and pregnanolone glutamate (IC50=51.7μM); (ii) physicochemical properties (logP and logD) were calculated; (iii) Caco-2 assay revealed that the permeability properties of compounds 2 and 4 are comparable with pregnanolone glutamate; (iv) compounds 1-4 have minimal or no adverse hepatic effect; (v) compounds 1-4 cross blood-brain-barrier.
- MeSH
- amidy MeSH
- buňky Hep G2 MeSH
- Caco-2 buňky MeSH
- hematoencefalická bariéra účinky léků metabolismus MeSH
- lidé MeSH
- magnetická rezonanční spektroskopie MeSH
- molekulární struktura MeSH
- neurotransmiterové látky chemie farmakologie MeSH
- reaktivní formy kyslíku metabolismus MeSH
- receptory N-methyl-D-aspartátu antagonisté a inhibitory metabolismus MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH