Pyrrolidine dithiocarbamate attenuate shock wave induced MDCK cells injury via inhibiting nuclear factor-kappa B activation

Shock wave lithotripsy (SWL)-induced renal damage appears to be multifactorial. Recent data indicated that the mechanism of renal tissue damage secondary to SWL is similar to that of ischernia reperfusion injury. Nuclear factor-kappa B (NFKB) and its target genes, inducible nitric oxide synthase (WOS) and cyclooxygense-2 (COX-2), have been demonstrated to play a very important role in a variety of cells or tissues ischernia reperfusion injuries. Thus in the present study, using an in vitro model MDCK cells, we investigated the role of NFKB and its target cytotoxic enzyme in shock wave-induced renal cellular damage. We also examined whether inhibition this pathway by pyrrolidine dithiocarbarnate (PDTC) is contributed to alleviate SWL-caused cell damage. Suspensions of MDCK cells were placed in containers for shock wave exposure. Three groups of six containers each were examined: control group, no shock wave treatment and SWL group, which received 100 shocks at 18 kV; 3 SWL + PDTC group. PDTC were added to the suspensions before shock wave exposure. After shock wave 0, 2, 4, 6 and 8 h, respectively, the cell supernatants were detected for the level of MDA and release of LDH. At post-shock wave 8 h, cells were harvested to detect the nuclear translocation of NF kappa Bp65 by immunofluorescence staining. Degradation Of I kappa B-a (an inhibitor protein of NFKB) and expression of WOS and COX-2 were also examined by western blotting. Our results indicated that shock wave initiated the apparent activation of NFKB, which in turn induced high expression of WOS and COX-2. Blocking degradation Of l kappa B-a by PDTC was contributed to decrease the expression of WOS. And the level of MDA and the release of LDH were also significantly reduced by using PDTC. However, the degree of COX-2 expression does not differ significantly between SWL and SWL + PDTC groups. Activation of NFKB and subsequent expression of its target cytotoxic enzyme have been demonstrated to be a potential and crucial mechanism in SWL-induced renal cell damage. Blocking this pathway by PDTC is contributed to protect against cellular damage from shock wave.