Effects of tristetraprolin on doxorubicin (adriamycin)-induced experimental kidney injury through inhibiting IL-13/STAT6 signal pathway.

To study the effects of Tristetraprolin (TTP) on Doxorubicin (DOX)-induced experimental kidney injury (KI). DOX was used to induce kidney injury in Balb/c male mice (in vivo) and in human kidney proximal tubular epithelial cell line (HK-2) and normal rat kidney epithelial cell line (NRK-52E) (in vitro). Body weight of experimental mice were recorded daily. Histological changes were observed using hematoxylin-eosin (HE) staining, and levels of blood urea nitrogen, serum creatinine and serum cystatin C in KI mice, and MDA, LDH and SOD in cells were detected using the corresponding kits. Meanwhile, the 2, 7-dichlorodihydrofluorescein diacetate (DCF-DA) fluorescent staining was used to assess intracellular levels of reactive oxygen species (ROS). TTP and Kim-1 expressions were measured by immunohistochemistry and western blot. The TNF-α, IL-1β and IL-6 levels were evaluated by ELISA. Expressions of IL-13, STAT6, p-STAT6, Bcl-2, Bax, cleaved-caspase3 were detected using western blot, respectively. Cell Counting Kit-8 (CCK-8) was conducted for analyzing cell viability, and cells apoptosis were assessed by DAPI staining and flow cytometry. DOX treatment decreased body weight and aggravated renal injury without changes in water and food intake. DOX significantly reduced TTP expression, stimulated IL-13/STAT6 pathway and elevated the levels of several factors related to renal injury, including inflammatory response, oxidative stress and cell apoptosis, which were significantly restored by the treatment of overexpression TTP in vitro. Overexpression of TTP significantly reduces DOX-induced adverse outcomes so as to prevent renal injury. Inhibition of IL-13/STAT6 pathway may be the functional mechanism under TTP in experimental KI. AJTR