Influence Of Hydroxamic Acid(SAHA)on Apoptosis Protein Expression In Kidney Of Rat After Hemorrhagic Shock

Objective:To investigate the effect of Suberoylanilide hydroxamic acid (SAHA) on the expression of apoptotic proteins in the kidney of rats of hemorrhagic shock.Methods:70 male Wistar rats were randomly divided into seven groups (n= 10):sham group (S group), no shock resuscitation group (HS group), Ringer fluid resuscitation group (LR group), Ringer solution SAHA complex resuscitation group (LR+SAHA group), SAHA resuscitation group (SAHA group),7.5% hypertonic saline resuscitation group (HSL group), and 7.5% hypertonic saline solution SAHA complex resuscitation group (HSL+SAHA group). A model of hemorrhagic shock was established. S group was placed catheter but had no bleeding and no recovery, and then was killed after observed for three hours; HS group had bleeding but no recovery, and then was killed immediately after shock for 60 min and specimens were to be tested; LR group was infused 1.5 times the amount of blood loss LR within 20 min in a constant rate; HSL group was infused of 4ml/kg HSL within 5 min in a constant rate; SAHA group was infused of 7.5mg/kg SAHA dissolved in 0.5ml saline within 5 min at a constant rate; LR+SAHA group was infused of 7.5 mg/kg SAHA dissolved in 1.5 times the amount of blood loss LR within 20 min in a constant rate; HSL+SAHA was infused of 7.5mg/kg SAHA dissolved in 4ml/kg HSL within 5 min at a constant rate; rats were sacrificed 3h after resuscitation. Light microscopy was used to observe renal pathological changes and renal injuries were scored using paller. The colorimetric method was employed to measure the levels of creatinine (CR) and blood urea nitrogen (BUN). Enzyme-linked immunosorbent assay (ELISA) was used to measure the damage index of urinary liver-type fatty acid binding protein (L-FABP). Superoxide dismutase (SOD) activity, malondialdehyde (MDA) activity, and levels of tumor necrosis factor (TNF-a) and interleukin IL-1β in renal tissues of rats were measured. Immunohistochemical technique was employed to detect the expression and distribution of renal tissues Bcl-2 and Bax. Western blot was used to detect changes in protein contents of renal tissue Bcl-2 and Bax.Results:Compared with the immediately after hemorrhagic shock, MAP of each recovery group was significantly higher (P<0.05).3h after recovery the MAP significantly decreased, and the LR+SAHA group, SAHA group, and HSL+SAHA group decreased to a lesser extent. Compared to HS pathological damage score which was 94.64±1.65, the damage score of the rest of recovery groups was significantly lower to different extent (P<0.05), wherein HSL+SAHA had a score of 33.45±1.03 (P<0.05). Compared with the HS group, the levels of BNU, CR, and L-FABP in all the recovery groups significantly decreased (P<0.05), wherein HSL+SAHA group decreased most (P<0.05). Compared with the HS group, MDA content in renal tissues of all the recovery groups declined (P<0.05), wherein HSL+SAHA group decreased most significantly (P<0.05). Compared with the HS group, SOD activity in renal tissues of HSL+SAHA group significantly increased (P<0.05) while the increase in the rest of the groups were not significant. Compared with the HS group, TNF-α and IL-1β content in LR group, LR+SAHA group, SAHA group, and HSL group remarkably increased (P<0.05) whereas significant declined (P<0.05) in HSL +SAHA group. Bax and Bcl-2 expression were mainly in tubular epithelial cells. Compared with the HS group, Bax in all the recovery groups was significantly lower (P<0.05), and lowest in HSL+SAHA group (P<0.05). Compared with the HS group, the content of Bcl-2 in renal tissues had different degrees of increase (P<0.05), wherein HSL+SAHA group increased most significantly (P<0.05).Conclusions:Hemorrhagic shock not only activated the expression of TNF-α and IL-1β in renal tissues, but also led to reduction of Bcl-2 in renal tissues and increase in the content of Bax protein, eventually causing apoptosis in renal cells; SAHA alone or compounded with recovery liquid can protect the kidney by enhancing the expression of Bcl-2 protein in the kidney and lowering the content of Bax protein, and SAHA compounded with HSL had most significant protective effects on the kidney, and its mechanism may be related to the activation of PI3K-AKT signaling pathway.