SAFit2

SAFit2 is a highly potent, highly selective FK506-binding protein 51 (FKBP51) inhibitor with a K_i of 6 nM and also enhances AKT2-AS160 binding^[1]. IC50 & Target: Ki: 6 nM (FKBP51)^[1] In Vitro: SAFit2 treatment increases the expression of pAKT2 (soleus and EDL muscle) and pAS160 (EDL muscle) in WT cells, but there is no effect of FKBP51 antagonism in 51KO cells. Moreover, following SAFit2 treatment, GLUT4 expression increases in the membrane fraction of primary EDL myotubes from WT mice, but not from 51KO mice^[2]. In Vivo: It is found that 30 days of SAFit2 administration leads to a reduction in body weight under both control and high-fat diet (HFD) conditions. SAFit2 significantly increases phosphorylated AKT2 and AS160 in EDL muscle and likewise increases expression of GLUT4 at the membrane in soleus muscle^[2]. When SAFit2 is applied 1 h before testing, no alterations in anxiety-related behavior are observed. However, SAFit2 treatment induces an anxiolytic phenotype in mice injected 16 h prior testing, which is reflected in a significantly increased open arm time in the elevated plus maze (EPM) (z=-2.183, p<0.05). SAFit2 treatment leads to a significantly reduced latency to enter the lit compartment (z=-2 to 265, p<0.05), as well as a significantly increased distance traveled (t₍₂₀₎=-2.371, p<0.05) in the lit compartment^[3].