Fig. 7

Experimental validation of pioglitazone’s proposed mechanism-of-action in Alzheimer’s disease (AD). a Network analysis highlighting the inferred mechanism-of-action for pioglitazone in AD. The potential molecular mechanisms of pioglitazone were inferred through integration of known drug targets and predicted AD risk or AD seed genes into brain-specific co-expressed protein–protein interactome network (see “Material and methods”). The green shadow emphasizes the two key proteins (GSK3B and CDK5) related to drug’s mechanism-of-action. Node size indicates the protein-coding gene expression level in brain compared with other 31 tissues from GTEx database (GTEx V8 release, 2020). Larger size highlighting the high expression level in brain compared with other tissues. We excluded the literature-derived protein–protein interactions. b Effects of pioglitazone on the cell viability of HMC3 cells. HMC3 cells were treated with indicated concentrations of pioglitazone for 48 h and cell viability was determined using MTT. Data are represented as mean ± SEM (n = 3) and each experiment was performed at least three times in duplicate. c Effects of pioglitazone on LPS-induced activation of GSK3β (d) and CDK5 (e) in human microglia HMC3 cells. HMC3 cells were pre-treated with pioglitazone and followed LPS treatment (1 μg/mL, 30 min). The total cell lysates were collected and subjected to Western blot analysis. Quantification data represent mean ± sd. of two independent experiments