Alp Sener

Renal Perfusion Pump vs. Cold Storage for Donation After Cardiac Death Kidneys: A Systematic Review.

PURPOSE Static cold storage is generally used to preserve kidney allografts from deceased donors. Hypothermic machine perfusion may improve the outcome after transplantation but few studies with limited power have addressed this issue. We reviewed evidence of the effectiveness of storing kidneys from deceased donors after cardiac death before transplantation using cold static storage solution or pulsatile hypothermic machine perfusion. MATERIALS AND METHODS We searched electronic databases in September 2011 for systematic reviews and/or meta-analyses, randomized, controlled trials and studies of other designs that compared delayed graft function and graft survival. Sources included The Cochrane Library, PubMed® and EMBASE®. Studies excluded from review included those that did not discriminate between donation after cardiac death and donation from a neurologically deceased donor. Primary outcomes were delayed graft function and 1-year graft survival. Statistical analysis was done using RevMan (http://ims.cochrane.org/revman). RESULTS Nine studies qualified for review. Pulsatile perfusion pumped kidneys from donation after cardiac death donors had decreased delayed graft function compared to kidneys placed in cold storage (OR 0.64, 95% CI 0.43-0.95, p = 0.03). There was a trend toward improved 1-year graft survival in the pulsatile perfusion group but statistical significance was not attained (OR 0.74, 95% CI 0.48-1.13, p = 0.17). CONCLUSIONS Pulsatile machine perfusion of donation after cardiac death kidneys appears to decrease the delayed graft function rate. We noted no benefit in 1-year graft survival. Due to the great heterogeneity among the trials as well as several confounding factors, the overall impact on allograft function and survival requires more study.

Focal segmental glomerular sclerosis in renal transplant recipients: predicting early disease recurrence may prolong allograft function.

Abstract:  Recurrence of focal segmental glomerular sclerosis (FSGS) in the allograft following renal transplantation can be graft threatening. To assess risk factors associated with FSGS recurrence, we analyzed 22 patients with FSGS who underwent transplantation between 1996 and 2004. Five patients (Group I, 23%) developed FSGS post‐transplantation. Of these patients, 60% had undergone bilateral nephrectomy (BN) for progressive disease compared with none of the patients that were free of recurrence (Group II) (p = 0.0006). Other factors linked with recurrent FSGS were time to first dialysis (Group I: 3.1 ± 1.1 yr vs. Group II: 11.9 ± 1.9 yr; p = 0.03), pre‐transplant proteinuria (Group I: 7.0 ± 1.8 g/d vs. Group II: 2.5 ± 0.7 g/d; p = 0.02), young age at transplantation (p = 0.09) and female sex (Group I: 80% vs. Group II: 24%; p = 0.021). Eighty percent of Group I patients received a living related transplant vs. 24% in Group II (p = 0.021). All grafts continue to function at last follow‐up with comparable serum creatinines. Overall, post‐transplant FSGS recurrence may be associated with BN, severity of pre‐transplant FSGS, female gender, and living donation. These patients should be monitored closely for early recurrence and may benefit from early plasmapheresis to restore and facilitate long‐term graft function.

CASE REPORT: Nonpalpable Scarring of the Penile Septum As a Cause of Erectile Dysfunction: An Atypical Form of Peyronie’s Disease

INTRODUCTION Men with nonpalpable isolated septal scars (ISS) identified with color duplex ultrasonography (CDU) comprise a group of previously unrecognized patients with wide-ranging sexual concerns. AIM We aim to identify the clinical characteristics of patients presenting with this atypical form of Peyronies disease characterized by the absence of palpable deformity. MATERIALS AND METHODS Of 482 consecutive patients who presented to a tertiary care erectile dysfunction (ED) clinic and underwent CDU after satisfying inclusion criteria, 27 (5.6%) men with nonpalpable ISS and no dorsal or ventral plaque were identified. MAIN OUTCOME MEASURES International Index of Erectile Function (IIEF), CDU, and clinical characteristics. RESULTS The median age of the men with nonpalpable ISS was 49 years. The length of time from onset of symptoms to presentation was 22 months, and the pretreatment IIEF score was 14. The remaining 455 men who underwent CDU were of similar age (48 years) but had a markedly lower IIEF score of 9.5 (statistical median). ISS patients presented with decreased penile rigidity (20), penile shortening (13), chronic pain with erection (13; mean 33 months), and the inability to maintain an erection (7). Fourteen men had failed phosphodiesterase-5 inhibitor therapy, and four reported unsatisfactory results. Management options included retrial with oral agents, intracavernous pharmacotherapy, verapamil injections, and surgery. CONCLUSIONS The clinician should be suspicious for nonpalpable ISS in men with sexual concerns who present with decreased penile rigidity, length loss, and chronic pain with erection. Our findings support the use of CDU for this patient group, particularly when previous treatment has failed, because men with ISS had a greater likelihood of having no palpable deformity or curvature and ongoing penile pain.

Hydrogen sulfide treatment improves long-term renal dysfunction resulting from prolonged warm renal ischemia-reperfusion injury

INTRODUCTION The incidence of renal cell carcinoma (RCC) continues to rise concurrently with the increased prevalence of end-stage renal disease worldwide. Treatment for small renal masses continues to be partial nephrectomy mostly involving the clamping of renal blood vessels. Although necessary, this technique results in warm renal ischemia and reperfusion injury (IRI) to the afflicted kidney. We have recently demonstrated that hydrogen sulfide (H2S), a novel endogenous gaseous molecule, protects against prolonged cold and short-term warm renal IRI. In the current study, we examined whether exogenous H2S has long-term protective effects against warm renal IRI associated with renal surgical procedures. METHODS Uni-nephrectomized Lewis rats underwent 1 hour of warm ischemia induced by clamping of the renal pelvis. Animals underwent either intraperitoneal treatment with phosphate buffered saline (PBS; IRI group) or PBS supplemented with 150 μM NaHS (H2S group), and were compared against Sham-operated rats. RESULTS H2S treatment improved long-term renal function as serum creatinine at day 7 was significantly decreased in the H2S group compared to IRI animals (p < 0.05). H2S treatment decreased the expression of pro-inflammatory markers TLR-4, TNF-α, IFNγ, IL-2 and ICAM-1, increased the expression of pro-survival molecule Bcl-2 and decreased the expression of pro-apoptotic marker BID at postoperative day 1. H2S-treated kidneys also showed a significant decrease (p < 0.05) in infiltration of macrophages at day 7 post-IRI compared to no treatment. CONCLUSION H2S treatment improved long-term renal function and decreased long-term inflammation associated with warm IRI, and may offer a novel therapeutic approach to preventing warm IRI-induced renal injury associated with renal surgical procedures.

Detrimental effects of prolonged warm renal ischaemia-reperfusion injury are abrogated by supplemental hydrogen sulphide: an analysis using real-time intravital microscopy and polymerase chain reaction.

Whats known on the subject? and What does the study add?

Supplemental hydrogen sulphide protects transplant kidney function and prolongs recipient survival after prolonged cold ischaemia-reperfusion injury by mitigating renal graft apoptosis and inflammation.

Whats known on the subject? and What does the study add?

Is There a Role for Pancreas Transplantation in Type 2 Diabetes Mellitus

The use of pancreas transplantation for type 2 diabetes mellitus is an emerging concept. Several lines of laboratory and clinical evidence suggest that in a carefully selected group of patients, long-term glycemic control and allograft function are similar to that observed for pancreas transplants performed for type 1 diabetes.

Carbon monoxide releasing molecules inhibit cell death resulting from renal transplantation related stress.

PURPOSE Organ cold storage and subsequent transplantation are associated with significant ischemia-reperfusion injury, leading to cell death, graft inflammation and decreased graft function. MATERIALS AND METHODS CORM-3s reduce oxidative stress and prevent inflammation in kidneys stored at 4C and subsequently transplanted. Graft survival and function are markedly improved compared to kidneys preserved and stored in University of Wisconsin solution alone. We determined whether CORM-3 has direct antiapoptotic effects on in vitro preparations of human HUVECs exposed to anoxic conditions. We also determined whether direct administration of CORM-3 to renal grafts before and/or after cold storage would prevent renal damage during the transplantation process. RESULTS CORM-3 supplementation led to a significantly increased frequency of live cells (mean ± SD 72.3% ± 1.9%, p <0.01), reduced apoptosis (14.9% ± 6.1%, p <0.01) and decreased mitochondrial transmembrane potential (40.2% ± 7.2%, p <0.05) in HUVECs exposed to 20 hours of cold storage compared to controls (11.6% ± 3.5%, 82.2% ± 2.3% and 78.2% ± 3.2%, respectively). In keeping with this antiapoptotic effect CORM-3 supplementation led to a mean 7.4 ± 2.1-fold up-regulation in Bcl-2 gene expression. CORM-3 supplementation in standard preservation solution was most beneficial at initial ischemic injury and before cold storage exposure. However, additional reflushing before vascular reperfusion showed an additive benefit to graft survival and function after transplantation. This was confirmed by decreased glomerular and tubular necrosis, and apoptosis in double flushed grafts. CONCLUSIONS CORM-3 supplementation in standard University of Wisconsin solution has a significant impact on decreasing cellular and graft injury, and improving survival through its antiapoptotic effects, which are likely mediated through mitochondrial membrane stabilization.

Hydrogen Sulfide Treatment Mitigates Renal Allograft Ischemia-Reperfusion Injury during Cold Storage and Improves Early Transplant Kidney Function and Survival Following Allogeneic Renal Transplantation

PURPOSE Ischemia-reperfusion injury is unavoidable during organ transplantation. Prolonged ischemia-reperfusion injury is detrimental to short-term and long-term graft function and survival. H2S is a recently characterized, endogenously produced gaseous molecule with important physiological roles that has been shown to be cytoprotective during tissue ischemia-reperfusion injury. The current study aimed to determine whether H2S could mitigate cold renal ischemia-reperfusion injury in the clinically relevant context of allogeneic renal transplantation. MATERIALS AND METHODS Following bilateral native nephrectomy Lewis rats underwent renal transplantation with kidneys from Brown Norway donor rats that were flushed with cold (4C) standard University of Wisconsin preservation solution (University of Wisconsin preservation solution group) or cold University of Wisconsin preservation solution plus 150 μM NaHS (H2S group) solution. Kidneys were stored for 6 hours at 4C in the same solution. Recipient animals were monitored for 14 days or until sacrifice using metabolic cages to assess various parameters of renal graft function. RESULTS H2S treatment improved early allograft survival and function, and decreased early levels of necrosis, apoptosis and Kim-1 compared to University of Wisconsin preservation solution alone. H2S treatment did not affect allograft rejection. Rather, it modulated the early allograft transcriptome to decrease the expression of renal injury, coagulation and cellular stress response genes, and increase the expression of cellular proliferation and Ifn-γ induced genes compared to University of Wisconsin preservation solution alone. CONCLUSIONS To our knowledge our findings are the first to show that H2S protects donor kidneys against cold ischemia-reperfusion injury in the context of allogeneic renal transplantation. This potentially represents a novel cost-effective therapeutic solution to mitigate ischemia-reperfusion injury and improve the clinical outcomes of renal transplantation.

Kidney Injury Molecule-1 Protects against Gα12 Activation and Tissue Damage in Renal Ischemia-Reperfusion Injury

Ischemic acute kidney injury is a serious untreatable condition. Activation of the G protein α12 (Gα12) subunit by reactive oxygen species is a major cause of tissue damage during renal ischemia-reperfusion injury. Kidney injury molecule-1 (KIM-1) is a transmembrane glycoprotein that is highly up-regulated during acute kidney injury, but the physiologic significance of this up-regulation is unclear. Here, we report for the first time that Kim-1 inhibits Gα12 activation and protects mice against renal ischemia-reperfusion injury. We reveal that Kim-1 physically interacts with and inhibits cellular Gα12 activation after inflammatory stimuli, including reactive oxygen species, by blocking GTP binding to Gα12. Compared with Kim-1(+/+) mice, Kim-1(-/-) mice exhibited greater Gα12 and downstream Src activation both in primary tubular epithelial cells after in vitro stimulation with H2O2 and in whole kidneys after unilateral renal artery clamping. Finally, we show that Kim-1-deficient mice had more severe kidney dysfunction and tissue damage after bilateral renal artery clamping, compared with wild-type mice. Our results suggest that KIM-1 is an endogenous protective mechanism against renal ischemia-reperfusion injury through inhibition of Gα12.