Utilizing Conductance Assay to Study Efficacy of Flavonoid Compounds on ΔF508-CFTR Recovery

Cystic Fibrosis (CF) is a life threatening genetic disease affecting 1 in every 3,200 Americans.  Flavonoids are plant-derived heterocyclic compounds that have been found to potentiate mutated, inactive Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) protein channels that cause CF.  In this investigation, Fissure Rat Thyroid (FRT) cells with inhibited chloride channels are treated in either a DMSO control or a 951 corrector assay prior to the addition of a flavonoid compound.  The electrical conductance of chloride channel activity is measured following the addition of agonists (forskolin and PG01) and inhibitor (Inh 172) using a transepithelial current clamp.  Conductance values are used to evaluate the effectiveness of the flavonoid compounds on the CFTR protein, where a higher conductance corresponds to a more active CFTR channel.  Flavonoids yielding the highest conductance values are tested at different concentrations to determine the efficacy and potency of each compound.  Results indicate that cells treated in a 951 corrector have an increased conductance compared to cells treated in DMSO.  Electrical conductance varies in dose response treatments of FRT cells.  This data is useful in the development of more effective cystic fibrosis therapies tailored specifically to improving the function of the CFTR protein.