β-Arrestin-2 enhances endoplasmic reticulum stress-induced glomerular endothelial cell injury by activating transcription factor 6 in diabetic nephropathy

Figure 7 Adeno-associated virus injection induced gene silencing of β-arrestin-2 ameliorates renal injury in streptozotocin-induced diabetic nephropathy mice. A: Relative mRNA levels of β-arrestin-2 in the renal cortex of mice after adeno-associated virus (AAV)-null (scramble) and AAV-shRNA-β-arrestin-2 (shRNA-β-arrestin-2) tail injection (mean ± SD, ^aP < 0.05 vs scramble/control, ^bP < 0.01 vs scramble/control, ^dP < 0.05 vs scramble/streptozotocin (STZ) treatment, n = 8); B: Western blot images showing protein level of β-arrestin-2 in the renal cortex of mice after AAV-null (scramble) and AAV-shRNA-β-arrestin-2 (shRNA-β-arrestin-2) tail injection (mean ± SD, ^aP < 0.05 vs scramble/control, ^bP < 0.01 vs scramble/control, ^dP < 0.05 vs scramble/STZ treatment, n = 8); C: Urinary albumin-to-creatinine ratio (UACR) in different groups of mice (mean ± SD, ^aP < 0.05 vs scramble/control, ^bP < 0.01 vs scramble/control, ^dP < 0.05 vs scramble/STZ treatment, n = 8); D: Periodic-acid Schiff staining showing changes of glomerular structure in different groups of mice (black bars = 20 μm, n = 8); E: TUNEL staining showing apoptosis of cells in the kidneys in different groups of mice (white bars = 50 μm, n = 8); F: Representative images showing protein levels of eNOS, ZO-1, and Occludin in the renal cortex of different groups of mice (mean ± SD, ^aP < 0.05 vs scramble/control, ^dP < 0.05 vs scramble/STZ treatment, n = 8); G: Western blot analysis showing expression of endoplasmic reticulum stress related proteins BiP, CHOP, and activating transcription factor 6 in the renal cortex of different groups of mice (mean ± SD, ^aP < 0.05 vs scramble/control, ^dP < 0.05 vs scramble/STZ treatment, n = 8). ATF6: Activating transcription factor 6; STZ: Streptozotocin.