Youhua Zhu

Preconditioning with physiological levels of ethanol protect kidney against ischemia/reperfusion injury by modulating oxidative stress.

Background Oxidative stress due to excessive production of reactive oxygen species (ROS) and subsequent lipid peroxidation plays a critical role in renal ischemia/reperfusion (IR) injury. The purpose of current study is to demonstrate the effect of antecedent ethanol exposure on IR-induced renal injury by modulation of oxidative stress. Materials and Methods Bilateral renal warm IR was induced in male C57BL/6 mice after ethanol or saline administration. Blood ethanol concentration, kidney function, histological damage, inflammatory infiltration, cytokine production, oxidative stress, antioxidant capacity and Aldehyde dehydrogenase (ALDH) enzymatic activity were assessed to evaluate the impact of antecedent ethanol exposure on IR-induced renal injury. Results After bilateral kidney ischemia, mice preconditioned with physiological levels of ethanol displayed significantly preserved renal function along with less histological tubular damage as manifested by the reduced inflammatory infiltration and cytokine production. Mechanistic studies revealed that precondition of mice with physiological levels of ethanol 3 h before IR induction enhanced antioxidant capacity characterized by significantly higher superoxidase dismutase (SOD) activities. Our studies further demonstrated that ethanol pretreatment specifically increased ALDH2 activity, which then suppressed lipid peroxidation by promoting the detoxification of Malondialdehyde (MDA) and 4-hydroxynonenal (HNE). Conclusions Our results provide first line of evidence indicating that antecedent ethanol exposure can provide protection for kidneys against IR-induced injury by enhancing antioxidant capacity and preventing lipid peroxidation. Therefore, ethanol precondition and ectopic ALDH2 activation could be potential therapeutic approaches to prevent renal IR injury relevant to various clinical conditions.

Effective induction of immune tolerance by portal venous infusion with IL-10 gene-modified immature dendritic cells leading to prolongation of allograft survival

Dendritic cells (DC) not only initiate T cell responses, but are also involved in the induction of tolerance. The functional properties of DC are strictly dependent on their state of maturation. It has been shown that immature DC can induce immune tolerance and prolong allograft survival. Interleukin-10 (IL-10) is an important immunosuppressive cytokine which inhibits maturation and function of DC. In order to improve the tolerogenicity of DC, we and others showed that adenovirus vectors can effectively mediate IL-10 genetic modification of DC, and IL-10 genetic modification can inhibit MHC II, B7.2, and CD40 expression, IL-12 secretion and the T cell stimulatory capacity of DC. The primary aim of this study is to examine the in vivo effects of this approach on allograft survival in a murine cardiac allograft transplantation model. To our surprise, we observed that infusion of immature DC genetically modified to express IL-10 (DC-IL-10) via the tail vein could not prolong allograft survival in the recipients, but shortened their survival. More interestingly, portal venous infusion of DC-IL-10 markedly prolonged allograft survival. The diverse effects of DC-IL-10 infusion through different routes may be due to the different immune responses to alloantigens in recipients that received DC-IL-10 via either the portal or the tail vein. Decreased cytotoxicity, polarization of Th2 response, poor T cell stimulating activity of liver DC and enhanced incidence of donor DC in the recipients may contribute to the more efficient prolongation of allograft survival observed after portal venous infusion of DC-IL-10. These results suggest that portal venous infusion may be an effective approach for immature DC to induce immune tolerance or hyporesponsiveness against donor antigens, and prolong allograft survival.

En bloc kidneys transplanted from infant donors less than 5 kg into pediatric recipients.

Background Given the shortage of donor kidneys, the use of grafts from deceased infant donors is a potential approach to expand the donor pool. Four infant en bloc kidney transplants in pediatric recipients were reported, performed between 2012 and 2013 in the center. Methods The en bloc graft was implanted extraperitoneally in the right iliac fossa. The distal end of the donor aorta was anastomosed end-to-end to the internal iliac artery, while the donor vena cava was anastomosed (end-to-side) to the external iliac vein. Both ureters were anastomosed individually to the bladder, with the exception of one case in which a donor bladder patch was anastomosed to the bladder. After the operation, the recipients received basiliximab as induction therapy followed by tacrolimus and mycophenolic acid for immunosuppression. Prophylactic anticoagulation was used postoperatively. Results Recipients included two girls and two boys with age ranging from 4.6 to 11.6 years. Donor age ranged from 33 to 56 days with weight ranging from 2.5 to 5.0 kg. After a follow-up of 2 to 14 months, patient and graft survivals were 100% and 75%, respectively. Complications included delayed graft function in one patient, urine leak in one, and anticoagulation-related hemorrhage in one. One graft was lost early from vascular thrombosis. The remaining three recipients had excellent graft function with median serum creatinine of 1.1 mg/dL (range, 0.8–1.3 mg/dL) at last follow-up. Conclusions Promising outcomes can be obtained from en bloc transplantation from infant donors. The use of this donor population for pediatric recipients should be encouraged.

Protective effects of sirtuin 3 in a murine model of sepsis-induced acute kidney injury

Acute kidney injury (AKI) is a rapid loss of kidney function characterized by damage to renal tubular cells driven by mitochondrial dysregulation and oxidative stress. Here, we used a murine caecal ligation and puncture (CLP) model of sepsis-induced AKI to study the role of sirtuin 3 (SIRT3), a NAD+ dependent deacetylase critical for the maintenance of mitochondrial viability, in AKI-related renal tubular cell damage and explored the underlying mechanisms. CLP induced alterations in kidney function and morphology were associated with SIRT3 downregulation, and SIRT3 deletion exacerbated CLP-induced kidney dysfunction, renal tubular cell injury and apoptosis, mitochondrial alterations, and ROS production in a knockout mouse model. SIRT3 deletion increased the CLP-induced upregulation of the NLRP3 inflammasome and apoptosis-associated speck-like protein, resulting in the activation of oxidative stress, increased production of the proinflammatory cytokines interleukin (IL)-1β and IL-18, and the enhancement of apoptosis, and these effects were reversed by antioxidant NAC. Our results suggest that SIRT3 plays a protective role against mitochondrial damage in the kidney by attenuating ROS production, inhibiting the NRLP3 inflammasome, attenuating oxidative stress, and downregulating IL-1β and IL-18.

In vitro effects of polyethylene glycol in University of Wisconsin preservation solution on human red blood cell aggregation and hemorheology.

Addition of hydroxyethyl starch (HES) to UW (University of Wisconsin) solution increases viscosity of the solution and red blood cell (RBC) aggregation. Recently, it was suggested that HES could be replaced by a new colloid, polyethylene glycol (PEG), in UW solution. The aim of this study was to see whether and how PEG affected RBC aggregation, and whether RBC aggregation parameters had any correlation with the molecular weight and concentration of PEG. After giving informed consent and signing consent documents, 12 healthy volunteers were enrolled in the study. Blood samples obtained from these volunteers were mixed with the test solutions with blood/solutions ratios of 5:1 and 1:1. Human RBC aggregation was investigated with an automatic hemorheological analyzer. Blood viscosity was measured with a cone-plate viscometer. Morphological characters of RBC aggregates were evaluated by light microscopy. It was found that viscosity was not affected by the Colloid-free UW solution. PEG20kDa (1 and 10 g/L) and PEG35kDa (1 g/L) had little effect on RBC aggregation, while PEG20kDa (30 g/L) and PEG35kDa (10 and 30 g/L) had a significant hyperaggregating effect on RBC. In conclusion, PEGs had a potential hyperaggregating effect on human RBC. This effect is correlated with PEG molecular weight and concentration. The use of large molecular weight and high concentration PEG in UW solution accounts for extended and accelerated aggregation of erythrocytes. The use of low concentration PEG35kDa (1 g/L) would be the optimal choice.

Optimizing the utilization of kidneys from small pediatric deceased donors under 15 kg by choosing pediatric recipients

Currently, most kidneys from small pediatric deceased donors are transplanted into adult recipients (i.e., PTA). However, due to the weight mismatch, there is a high discard rate and a high ratio of EBKTs if adopting PTA. Here, we sought both to optimize utilization of these challenging but scarce donor grafts by selecting pediatric recipients and to characterize the feasibility and efficacy of this PTP allocation strategy. From February 2012 to October 2014, kidneys from 27 infant donors ≤15 kg were procured and distributed to 38 pediatric candidates in our center. The grafts were utilized for EBKT if the donor weighed 2.5–5 kg and for SKT if the donor weighed 5–15 kg, leading to 10 EBKTs and 28 SKTs. The overall utilization rate from small pediatric deceased donors was 94.12%. After a follow‐up of 3–26 months, the graft survival rate was 89.47%, with four graft losses due to vascular thrombosis. Kidneys from low‐body‐weight donors should be applied to pediatric recipients, and the kidneys from infant donors ≥5 kg can be used in single‐kidney‐transplant procedures at experienced centers to optimize utilization.

Cost analysis of living donor kidney transplantation in China: A single-center experience

BACKGROUND Kidney transplantation is the most cost-effective option for the treatment of end-stage renal disease, but the financial aspects of kidney transplantation have not yet been fully investigated. The purpose of this study was to determine the hospital cost of living donor kidney transplantation in China and to identify factors associated with the high cost. MATERIAL/METHODS Demographic and clinical data of 103 consecutive patients who underwent living donor kidney transplantation from January 2007 to January 2011 at our center were reviewed, and detailed hospital cost of initial admission for kidney transplantation was analyzed. A stepwise multiple regression analysis was computed to determine predictors affecting the total hospital cost. RESULTS The median total hospital cost was US

Single kidneys transplanted from small pediatric donors less than 15 kilograms into pediatric recipients.

10,531, of which 69.2% was for medications, 13.2% for surgical procedures, 11.4% for para clinics, 3.7% for accommodations, 0.5% for nursing care, and 2.0% for other miscellaneous medical services. A multivariate stepwise logistic regression model for overall cost of transplantation revealed that the length of hospital stay, induction therapy, steroid-resistant rejection, maintenance therapy, infection status and body weight were independent predictors affecting the total hospitalization cost. CONCLUSIONS Although the cost of living donor kidney transplantation in China is much lower than that in developed countries, it is a heavy burden for both the government and the patients. As medications formed the greater proportion of the total hospitalization cost, efforts to reduce the cost of drugs should be addressed.

A New HC-A II Solution for Kidney Preservation: A Multi-Center Randomized Controlled Trial in China

K idney transplantation is currently the best treatment option for children with end-stage renal disease and offers the best hope to avoid detrimental perturbations in both physical and cognitive developments in these children when compared with dialysis (1). However, although children are given priority in receiving grafts, the severe shortage of organ donors limits the number of pediatric transplants. To increase organ use, one approach that our center has adopted has been transplantation of kidneys from small pediatric donors (weight G 15 kg) into the pediatric recipients. Kidney transplantation from small pediatric donors may be performed as single or en bloc. The en bloc transplants technique could avoid small anastomotic vessel size and provide greater renal mass. More recently, our report of successful outcomes of pediatric en bloc transplantation from infant donors (weight G 5 kg) into pediatric recipients has provided evidence of its efficacy (2). However, the en bloc pediatric transplants halve the number of potential recipients and result in a high risk of vascular and urinary complications. Forced by the extreme shortage of organs, we have adopted some more aggressive approaches to expand the donor pool, including single use of kidneys from small pediatric donors. In this study, we reviewed our recent experience with single kidney transplantation of small pediatric donors less than 15 kg to pediatric recipients. From March 2013 to March 2014, 15 pediatric patients received single kidney transplants from pediatric donors less than 15 kg in our center. The single allograft was implanted extraperitoneally in the right iliac fossa. The donor artery with a Carrel patch was anastomosed endto-end to the internal iliac artery using continuous 6-0 absorbable suture. The donor renal vein was anastomosed (endto-side) to the external iliac vein using continuous 6-0 absorbable suture. The ureter was anastomosed to the bladder using separate extravesical ureteroneocystostomies, and double-J stent (4 French, 12 cm) was placed. In all cases, the stents were removed 6 weeks postoperatively. To prevent thrombosis, prophylactic anticoagulation was preceded by using a continuous intravenous infusion of heparin, at a dose of 5 U/kg/h for the first week after transplantation, after which aspirin with or without clopidogrel was given daily. For the first week, the activated partial thromboplastin time was maintained to less than 1.5 times as high as the normal value. All patients were given basiliximab as induction therapy at a dose of 1 mg/kg intravenously for a total of three doses. Intravenous methylprednisolone was started on the day of transplant at an initial dose of 10 mg/kg per day and gradually tapered off in the first week after transplantation. Maintenance immunosuppression consisted of tacrolimus and enteric-coated mycophenolate sodium (Myfortic). Considering the increased clearance of tacrolimus in children, pediatric patients were given higher initial dosage of tacrolimus in this study. To achieve a therapeutic level of tacrolimus early after transplantation, intravenous tacrolimus was started by postoperative day 2 at 0.05 mg/kg/day (target level of 10Y12 ng/mL) and switched to oral tacrolimus (0.15 mg/kg/dose twice daily) on postoperative day 10. Entericcoated mycophenolate sodium was started by postoperative day 3 at 540 mg/m per day in two divided doses. The hospital records of these patients were retrospectively reviewed, and the parameters recorded were demographic characteristics of the recipients and donors, serum creatinine levels at discharge and at last follow-up, complications, and the overall outcome of patient and graft. GFR was estimated with the Schwartz formula (3). Kidney graft sizes were evaluated by ultrasonography at 1 week and 3, 6, and 12 months postoperatively. Graft loss was defined as a permanent return to dialysis, graft nephrectomy, or recipient death. Delayed graft function (DGF) was defined as the need for dialysis during the first week after transplantation with eventual graft function. Continuous variables with normal distribution were expressed as mean T SD, whereas continuous variables with non-normal distribution were expressed as median (range). Demographic data are shown in Table 1. Of these 15 pediatric recipients, six were boys and nine were girls. Median age was 9.5 years (range, 5.4Y16.0 years), and their median pretransplant weight was 24 kg (range, 15Y37.5 kg). Median duration of dialysis was 15 months (range, 1Y72 months). Kidneys from eight small pediatric donors (Maastricht Category III) were recovered by local organ procurement organizations and allocated to our center by the China Organ Transplant Response System. The causes of death included brain injury, drowning, congenital heart disease, viral encephalitis, severe diarrhea, and diaphragmatic paralysis. Donor age ranged from 5 to 30 months with weight ranging from 5.5 to 14 kg. Cold ischemic times ranged from 7 to 14 hr, whereas the warm ischemic times (revascularization time) were 38 to 52 min. All kidneys initially arrived as en bloc, and they were split into two single grafts in our center. One single kidney was discarded because of severe vascular damage. Follow-up data are shown in Table 2. Patient and graft survivals were 100% and 93.3%, respectively during the follow-up period. One graft was lost early from vascular thrombosis on postoperative day 6. A dialysis-related hypotension in the previous day may be a potential cause. The median follow-up was 6.5 months (range, 3 to 16 months). Delayed graft function was present in seven patients (46.7%), which were managed by peritoneal dialysis for 1 to 2 weeks postoperatively. All patients recovered without long-term consequences. Acute rejection occurred in one patient (6.7%), who responded well to steroid bolus treatment. There was one reoperation for ureteral stenosis occurring in one patient. After surgical revision, this patient suffered no further complications. There were no complications of the anticoagulation therapy during the follow-up period. Of the remaining 14 recipients, all had excellent graft function with median serum creatinine of 0.97 mg/dL (range, 0.60Y2.52 mg/dL) at discharge and 0.78 mg/dL (range, 0.43Y1.75 mg/dL) at last follow-up. The estimated GFR was 72.9 mL/1.73 m/min (range, 27.1Y89.5 mL/1.73 m/min) at discharge and 89.8 mL/1.73 m per min (range, 37.6Y150.7 mL/1.73 m/min) at last follow-up. All kidney grafts showed significant growth in length by ultrasonography. The median length of the grafts increased from 6.75 cm at 1 week * 2014 Lippincott Williams & Wilkins Letters to the Editor e97

Cannabidiol Attenuates Palmitic Acid-Induced Injury in Cultured Hepatocytes Through Promoting Autophagic Flux

BACKGROUND Hypertonic citrate adenine (HC-A) solution, containing citrate and adenine, has become the most widely used preservation solution in isolated kidney preservation in China. More than 30 years of clinical application has demonstrated that HC-A is safe and effective. With higher requirement for kidney preservation and less tolerance of preservation-related graft dysfunction, a new solution, HC-A II, for kidney preservation was developed by Shanghai Changzheng Hospital. MATERIAL/METHODS Upon approval from the State Food and Drug Administration of China (SFDA), a multi-center randomized controlled trial was performed to study the efficacy and safety of HC-A II in kidney preservation from 2008 to 2012, using histidine-tryptophan-ketoglutarate solution (HTK) as control (HC-A, n=137, and HTK, n=140). There were no differences with regard to donor and recipient demographics or cold ischemia. RESULTS The trial results showed no significant difference in DGF rate, or patient or graft survival between the 2 groups. No significant difference between the 2 groups was found in the percentage of patients whose serum creatinine (SCr) test results returned to normal within 28 days (P>0.05), nor were there a significant difference in safety evaluation (P>0.05). CONCLUSIONS HC-A II and HTK appear to have similar efficacy in isolated kidney preservation.