Figure 3.
Brp-39 protects against tubular cell apoptosis via activation of PI 3-kinase. (A) Representative images of outer medulla from kidney sections obtained from WT and Brp39−/− mice 3 days after 25 minutes of I/R and stained for TUNEL+ apoptotic cells (green staining indicating TUNEL+ nuclei). (B) Quantification of apoptotic tubular cells identified as in A. n=5. **P<0.01. (C) Representative images of outer medulla from kidney sections obtained as in A and stained for Ki-67+ proliferating cells (red staining indicates Ki-67+ nuclei). (D) Quantification of proliferating tubular cells identified as in C. n=5. **P<0.01. (E) Cultured MPT cells are serum starved overnight and stimulated for the indicated time with recombinant Brp-39 (10 μM), followed by lysis and immunoblotting with pAkt and total Akt (lower panel). Upper panel shows quantification of pAkt from three separate experiments normalized to tAkt. *P<0.05 versus baseline. (F) Cells treated as in E and immunoblotted for pErk (p42/44) and total Erk. n=3. *P<0.05 versus 0 or 1 hour. (G) PTECs treated for 6 hours with H2O2 ± Brp-39 ± LY294002 and then fixed and stained for apoptosis using TUNEL. n=4 separate experiments. *P<0.05 versus control; **P<0.05 versus H2O2 alone; ***P=NS versus H2O2 alone; ****P=0.02 versus H2O2 +Brp-39. Original magnification, ×400 in A and C.