Science and Technology Production
Congress
Authorship
Echeverría E
;
RIPOLL, SONIA
;
Fabián L
;
Monczor F
;
Shayo C
;
Lorenzano-Menna P
;
Fernández N
Date
2018
Publishing House and Editing Place
Fundación Revista Medicina
Summary
Information provided by the agent in
SIGEVA
GPCR kinase 2 (GRK2) plays a major role in GPCRs desensitization and hasbeen extensively validated as an effective target for heart failure (HF)treatment. Its overexpression is associated to disease progression due to thelack of cardiac BAR responsiveness. Accordingly, we have previously obtainedfour compounds (C2, C3, C4, C5) that exert significant in vitro GRK2 inhibitoryactivity, postulating them as suitable candidates for in vivo testing. However,there are several risks inherent in preclini...
GPCR kinase 2 (GRK2) plays a major role in GPCRs desensitization and hasbeen extensively validated as an effective target for heart failure (HF)treatment. Its overexpression is associated to disease progression due to thelack of cardiac BAR responsiveness. Accordingly, we have previously obtainedfour compounds (C2, C3, C4, C5) that exert significant in vitro GRK2 inhibitoryactivity, postulating them as suitable candidates for in vivo testing. However,there are several risks inherent in preclinical drug discovery that might leadto drugs attrition in late stages. Therefore, the objective of this work was toidentify potential early failures of our hits before reaching in vivo phases. To achieve this, we evaluated their ADMET (Absorption-Distribution-Metabolism-Excretion-Toxicity)properties. As a lipophilicity descriptor, experimental logP was obtained byRP-HPLC. Hits cytotoxicity was assessed in U937 and HepG2 cells by trypan blueexclusion test after 48hs treatment. Even though all compounds exhibited anappropriate lipophilicity, with logP values ranging from 1 to 3, compounds C3and C5 stood out as they did not affect cellular viability, while C2 presentedan EC50=10,5µM and C4 an EC50=17,2µM. Moreover, GRK2 desensitizes GPCRs that couple to different G-proteins.Since compounds that specifically potentiate cAMP could be of interest for HFtreatment, we compared their ability to increase responsiveness of GPCRs thatcouple to different G-proteins. Initial cell-based screening assays proved thatthe hits increased cAMP response of H2R (histamine type 2 receptor).Nonetheless we observed that compound C5 also increased histamine-stimulatedintracellular calcium release in A549 cell line endogenously expressing H1R(histamine type 1 receptor), revealing an undesirable promiscuous behavior. In conclusion, we applied strategies to mitigate the risks of drugattrition in late phases of clinical trials, increasing the confidence in ourcandidate compound C3 for proceeding to HF animal models research.
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Key Words
SIGNALINGRGSGRK2DESENSITIZATION