Tuesday, December 17, 2019

Cellular Stress-Modulating Drugs Can Potentially Be Identified by in Silico Screening with Connectivity Map (CMap)

Gao Y, Sungwoo Kim, Lee YI, Lee J; International Journal of Molecular Sciences, 09 Nov 2019, 20(22) DOI: 10.3390/ijms20225601

A target-based drug discovery method currently being used widely (reverse pharmacology) may not be adequate to uncover novel drugs targeting cellular stresses and related diseases. The connectivity map (CMap) is an online pharmacogenomic database cataloging gene expression data from cultured cells treated individually with various chemicals, including a variety of phytochemicals. Moreover, by querying through CMap, researchers may screen registered chemicals in silico and obtain the likelihood of drugs showing a similar gene expression profile with desired and chemopreventive conditions. Thus, CMap is an effective genome-based tool to discover novel chemopreventive drugs.


Drug discovery using the connectivity map (CMap). (A) Target-based drug discovery. (B) Phenotypic drug discovery. (C) CMap-based drug discovery. Gene signature of the biological or pathological state of interest can be used as a query to search through CMap. CMap provides the search result as a list of small molecules scored to predict their probability to mimic or reverse gene expression profiles of the state of interest. Candidate chemicals can be further tested in in vitro cell culture and in vivo animal experiments before proceeding with clinical trials to human subjects.

Monday, December 16, 2019

Functional characterization of frataxin isoforms and mechanisms of regulation of frataxin expression

Autores: Mauro Agrò. Directores de la Tesis: Javier Díaz Nido (dir. tes.), Alfredo Giménez-Cassina Sendón (codir. tes.). Lectura: En la Universidad Autónoma de Madrid ( España ) en 2019. Idioma: español.


The regulation of frataxin gene expression is another issue of major interest for its possible therapeutic relevance. Several factors including Erythropoietin and some Epo-mimetic molecules have been reported to increase frataxin levels. There are some drawbacks, since canonical Epo can cause hematocrit problems, while some of the derivative peptides described are known to be highly unstable, with a very low half-life in the organism. For this reason, we decided to focus on a retro-enantiomeric version of a HBSP-based peptide, called EPO2. We described in this work the positive regulatory effects on frataxin of this synthetic epomimetic peptide, both in vitro in several cell models and in vivo in the cerebellum of wild type mice.
Finally, we reported the effects of spontaneous physical activity in wild type mouse cerebellum on frataxin expression. Frataxin levels appeared positively modulated after exercise, suggesting a post-transcriptional regulation mechanism. We investigated for possible mediators of this beneficial effect by qPCRs and through a cytokine array which highlighted the upregulation of several factors, including the neurotrophin NT-3, SHH protein, MIP-1α and IFN-γ, pointing the way to a multi-layered regulatory complex behind frataxin modulation set up by physical exercise.