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P30 NAHS and STS treatment in ischemia–reperfusion injury in rats
Abstracts / Nitric Oxide 39 (2014) S16–S49
Conclusion: The endogenous H2S/CBS pathway was downregulated during the development of salt-sensitive hypertensive in Dahl rats. http://dx.doi.org/10.1016/j.niox.2014.03.078
P29 Dialysate sulfate levels reflect nutrional status Anne M. Koning a,b, Esmee M. Ettema c, Marinda M. Bakker a, Henri G.D. Leuvenink b, Andreas Pasch d, Stephan J.L. Bakker c, Casper F.M. Franssen c, Harry van Goor a a Department of Pathology and Medical Biology, University Medical Center Groningen (UMCG), University of Groningen (RUG), Groningen, The Netherlands b Department of Surgery, University Medical Center Groningen (UMCG), University of Groningen (RUG), Groningen, The Netherlands c Department of Nephrology, University Medical Center Groningen (UMCG), University of Groningen (RUG), Groningen, The Netherlands d Department of Nephrology, Bern University Hospital, Bern, Switzerland Higher urinary sulfate is associated with a favorable cardiovascular profile in renal transplant recipients. Sulfate can be derived from the intake of sulfur-containing amino acids, but is also an end product of, and thus may reflect, hydrogen sulfide metabolism. Since cardiovascular problems are likely to originate pre-transplantation, we hypothesized that the same association could be found for sulfate levels in dialysate of patients with end stage renal disease. Data were taken from a cohort of 29 patients who underwent 240 min of standard hemodialysis. Patient characteristics, including protein catabolic rate (PCR) and data from several time points on dialysis and hemodynamic parameters were available. Sulfate levels in dialysate from 6 time points were measured by Ion Chromatography and total excretion was determined by computing the area under the curve (1.10 ± 0.475 mmol/L). No associations were found between levels of sulfate in dialysate and hemodynamic parameters (systolic and diastolic blood pressure, mean arterial pressure and heart frequency), although we did observe positive trends. Above average sulfate excretion was found to associate with a higher PCR (+0.212 ± 0.0589 g/kg/day, p = 0.0012). Also, total sulfate excretion correlated with total ultrafiltration volume (R = 0.492, p = 0.007). We thus conclude that dialysate sulfate levels relate to a favorable nutritional intake, rather than to hemodynamics, in hemodialysis patients. http://dx.doi.org/10.1016/j.niox.2014.03.079
P30 NAHS and STS treatment in ischemia–reperfusion injury in rats Anne M. Koning a,b, Henri G.D. Leuvenink b, Dane H. Hoeksma b, Andreas Pasch c, Harry van Goor a a Department of Pathology and Medical Biology, University Medical Center Groningen (UMCG), University of Groningen (RUG), Groningen, The Netherlands b Department of Surgery, University Medical Center Groningen (UMCG), University of Groningen (RUG), Groningen, The Netherlands c Department of Nephrology, Bern University Hospital, Bern, Switzerland Ischemia–reperfusion injury (IRI) is a major cause of renal transplant dysfunction. Hydrogen sulfide (H2S) can attenuate IRI in mice by metabolic suppression and vasodilatory, anti-inflammatory and anti-oxidant effects. We now investigated the protective properties of
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H2S (sodium hydrosulfide (NaHS)) and its endogenous donor thiosulfate (sodium thiosulfate (STS)) in unilateral IRI in rats and in isolated rat kidneys. In vivo, rats underwent 35 min of unilateral warm ischemia (WI) and received vehicle, NaHS (5.6 mg/kg/day) or STS (1 g/kg/day) via intra-peritoneal injections twice daily from 48 h before WI until sacrifice at 24 or 96 h after reperfusion (n = 7/group). Kidneys were studied for tubular epithelial damage (KIM-1), macrophages (ED1), early fibrotic changes (alphaSMA) and oxidative stress (MDA). Ex vivo, kidneys were exposed to 1 mM NaHS (n = 4) for 40 min and O2 consumption and ATP were compared to controls (n = 3). Immunohistochemistry (KIM-1, ED1, alphaSMA) showed no benefit from NaHS or STS treatment. Also, at mRNA level no differences were found (KIM-1, alphaSMA). MDA levels were the same for all treatment groups. Ex vivo, H2S reduced O2 consumption and ATP both by over 50% (p < 0.05). In conclusion, in vivo, NaHS and STS treatment do not protect from IRI in rats. Ex vivo data however, show metabolic suppression in isolated rat kidneys. These data indicate a possible role for H2S as a treatment modality for ex vivo kidney transplant protection. http://dx.doi.org/10.1016/j.niox.2014.03.080
P31 Hydrogen sulfide treatment improves graft function and survival following prolonged cold ischemia and allogeneic renal transplantation Ian Lobb a,b, Michael Davison b, Zhu Lan b, Jifu Jian b, Alp Sener a,b a Department of Microbiology and Immunology, Western University, London, Ontario, Canada b Matthew Mailing Centre for Translational Transplant Studies, London Health Sciences Centre, London, Ontario, Canada Introduction: Organ procurement is inherently associated with ischemia–reperfusion injury (IRI), resulting from loss and subsequent restoration of blood flow, and is detrimental to graft function and survival. Treatment of donor organs with small molecules such as hydrogen sulfide (H2S) may be a novel method of mitigating IRI during transplantation. We postulated that H2S treatment could mitigate IRI during cold organ storage and subsequent genetically mismatched (allogeneic) renal transplantation (RTx), improving allograft function and survival. Methods: Following bilateral native nephrectomy, recipient Lewis rats underwent RTx with kidneys obtained from Brown Norway donor rats that were flushed with either University of Wisconsin preservation solution (UW group) or UW + H2S (150 lM NaHS; H2S group) and stored for 24 h at 4°C in the same solution. Serum was obtained on subsequent post-operative (PO) days and creatinine was used as a surrogate marker of graft function. Results: H2S treated animals exhibited significantly improved survival compared to UW animals (p < 0.01), with UW animals exhibiting 0% survival by PO day 4 and H2S treated animals retaining 20% survival by PO day 14 (end of time course). As well, UW treated animals exhibited markedly increased serum creatinine levels at both PO days 2 and 4 compared to H2S animals. Conclusion: These findings indicate that H2S treatment can mitigate graft injury following prolonged periods of cold IRI, improving initial graft function and possibly delaying graft rejection. H2S treatment could represent a novel method of mitigating IRI during transplantation, thereby improving clinical outcomes. http://dx.doi.org/10.1016/j.niox.2014.03.081
Conclusion: The endogenous H2S/CBS pathway was downregulated during the development of salt-sensitive hypertensive in Dahl rats. http://dx.doi.org/10.1016/j.niox.2014.03.078
P29 Dialysate sulfate levels reflect nutrional status Anne M. Koning a,b, Esmee M. Ettema c, Marinda M. Bakker a, Henri G.D. Leuvenink b, Andreas Pasch d, Stephan J.L. Bakker c, Casper F.M. Franssen c, Harry van Goor a a Department of Pathology and Medical Biology, University Medical Center Groningen (UMCG), University of Groningen (RUG), Groningen, The Netherlands b Department of Surgery, University Medical Center Groningen (UMCG), University of Groningen (RUG), Groningen, The Netherlands c Department of Nephrology, University Medical Center Groningen (UMCG), University of Groningen (RUG), Groningen, The Netherlands d Department of Nephrology, Bern University Hospital, Bern, Switzerland Higher urinary sulfate is associated with a favorable cardiovascular profile in renal transplant recipients. Sulfate can be derived from the intake of sulfur-containing amino acids, but is also an end product of, and thus may reflect, hydrogen sulfide metabolism. Since cardiovascular problems are likely to originate pre-transplantation, we hypothesized that the same association could be found for sulfate levels in dialysate of patients with end stage renal disease. Data were taken from a cohort of 29 patients who underwent 240 min of standard hemodialysis. Patient characteristics, including protein catabolic rate (PCR) and data from several time points on dialysis and hemodynamic parameters were available. Sulfate levels in dialysate from 6 time points were measured by Ion Chromatography and total excretion was determined by computing the area under the curve (1.10 ± 0.475 mmol/L). No associations were found between levels of sulfate in dialysate and hemodynamic parameters (systolic and diastolic blood pressure, mean arterial pressure and heart frequency), although we did observe positive trends. Above average sulfate excretion was found to associate with a higher PCR (+0.212 ± 0.0589 g/kg/day, p = 0.0012). Also, total sulfate excretion correlated with total ultrafiltration volume (R = 0.492, p = 0.007). We thus conclude that dialysate sulfate levels relate to a favorable nutritional intake, rather than to hemodynamics, in hemodialysis patients. http://dx.doi.org/10.1016/j.niox.2014.03.079
P30 NAHS and STS treatment in ischemia–reperfusion injury in rats Anne M. Koning a,b, Henri G.D. Leuvenink b, Dane H. Hoeksma b, Andreas Pasch c, Harry van Goor a a Department of Pathology and Medical Biology, University Medical Center Groningen (UMCG), University of Groningen (RUG), Groningen, The Netherlands b Department of Surgery, University Medical Center Groningen (UMCG), University of Groningen (RUG), Groningen, The Netherlands c Department of Nephrology, Bern University Hospital, Bern, Switzerland Ischemia–reperfusion injury (IRI) is a major cause of renal transplant dysfunction. Hydrogen sulfide (H2S) can attenuate IRI in mice by metabolic suppression and vasodilatory, anti-inflammatory and anti-oxidant effects. We now investigated the protective properties of
S25
H2S (sodium hydrosulfide (NaHS)) and its endogenous donor thiosulfate (sodium thiosulfate (STS)) in unilateral IRI in rats and in isolated rat kidneys. In vivo, rats underwent 35 min of unilateral warm ischemia (WI) and received vehicle, NaHS (5.6 mg/kg/day) or STS (1 g/kg/day) via intra-peritoneal injections twice daily from 48 h before WI until sacrifice at 24 or 96 h after reperfusion (n = 7/group). Kidneys were studied for tubular epithelial damage (KIM-1), macrophages (ED1), early fibrotic changes (alphaSMA) and oxidative stress (MDA). Ex vivo, kidneys were exposed to 1 mM NaHS (n = 4) for 40 min and O2 consumption and ATP were compared to controls (n = 3). Immunohistochemistry (KIM-1, ED1, alphaSMA) showed no benefit from NaHS or STS treatment. Also, at mRNA level no differences were found (KIM-1, alphaSMA). MDA levels were the same for all treatment groups. Ex vivo, H2S reduced O2 consumption and ATP both by over 50% (p < 0.05). In conclusion, in vivo, NaHS and STS treatment do not protect from IRI in rats. Ex vivo data however, show metabolic suppression in isolated rat kidneys. These data indicate a possible role for H2S as a treatment modality for ex vivo kidney transplant protection. http://dx.doi.org/10.1016/j.niox.2014.03.080
P31 Hydrogen sulfide treatment improves graft function and survival following prolonged cold ischemia and allogeneic renal transplantation Ian Lobb a,b, Michael Davison b, Zhu Lan b, Jifu Jian b, Alp Sener a,b a Department of Microbiology and Immunology, Western University, London, Ontario, Canada b Matthew Mailing Centre for Translational Transplant Studies, London Health Sciences Centre, London, Ontario, Canada Introduction: Organ procurement is inherently associated with ischemia–reperfusion injury (IRI), resulting from loss and subsequent restoration of blood flow, and is detrimental to graft function and survival. Treatment of donor organs with small molecules such as hydrogen sulfide (H2S) may be a novel method of mitigating IRI during transplantation. We postulated that H2S treatment could mitigate IRI during cold organ storage and subsequent genetically mismatched (allogeneic) renal transplantation (RTx), improving allograft function and survival. Methods: Following bilateral native nephrectomy, recipient Lewis rats underwent RTx with kidneys obtained from Brown Norway donor rats that were flushed with either University of Wisconsin preservation solution (UW group) or UW + H2S (150 lM NaHS; H2S group) and stored for 24 h at 4°C in the same solution. Serum was obtained on subsequent post-operative (PO) days and creatinine was used as a surrogate marker of graft function. Results: H2S treated animals exhibited significantly improved survival compared to UW animals (p < 0.01), with UW animals exhibiting 0% survival by PO day 4 and H2S treated animals retaining 20% survival by PO day 14 (end of time course). As well, UW treated animals exhibited markedly increased serum creatinine levels at both PO days 2 and 4 compared to H2S animals. Conclusion: These findings indicate that H2S treatment can mitigate graft injury following prolonged periods of cold IRI, improving initial graft function and possibly delaying graft rejection. H2S treatment could represent a novel method of mitigating IRI during transplantation, thereby improving clinical outcomes. http://dx.doi.org/10.1016/j.niox.2014.03.081