Trifluoperazine induces apoptosis through the upregulation of Bax/Bcl-2 and downregulated phosphorylation of AKT in mesangial cells and improves renal function in lupus nephritis mice

The inhibition of mesangial cell (MC) proliferation has become an important therapy in preventing glomerular proliferation diseases. Trifluoperazine (TFP) has been reported to inhibit the proliferation of several types of cancer cell, however, the effects of TFP in renal proliferation diseases remain to be fully elucidated. The present study examined the effects of TFP on the proliferation of MCs and quantified cell apoptosis progression in vivo and in vitro. The effects of various TFP concentrations and treatment durations on cell proliferation and cell apoptosis in vitro were analyzed using flow cytometry in conjunction with a Cell Counting kit-8 assay. Cell proliferation in vivo was determined using hematoxylin and eosin staining and immunohistochemistry of Ki67. The expression of the two cell apoptosis-related proteins, B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax), were estimated using western blot analysis and immunohistochemistry in vivo and in vitro. TFP-induced phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathways were also estimated using western blot analysis. These results suggested that TFP inhibited MC proliferation in a dose- and time-dependent manner. It was found that TFP inhibited the abnormal proliferation of MCs, which was stimulated by 20% fetal bovine serum in vitro and in lupus MRL/lpr mice. TFP promoted cell apoptosis, downregulated the expression of Bcl-2 and upregulated the expression of Bax in a dose-dependent manner at mRNA and protein levels. In addition, TFP inhibited phosphorylated AKT, potentially leading to the suppressed activation of PI3K/AKT signaling pathways. TFP treatment significantly decreased the levels of blood urea nitrogen and serum creatinine, but had no significant effects on the body weight and liver function of the lupus mice. These results validated and reinforced the potential of TFP in the treatment of mesangial proliferative diseases.