Attenuation of Sepsis-Induced Acute Kidney Injury by Exogenous H2S via Inhibition of Ferroptosis.

Sepsis-associated acute kidney injury (SA-AKI) results in significant morbidity and mortality, and ferroptosis may play a role in its pathogenesis. Our aim was to examine the effect of exogenous H2S (GYY4137) on ferroptosis and AKI in in vivo and in vitro models of sepsis and explore the possible mechanism involved. Sepsis was induced by cecal ligation and puncture (CLP) in male C57BL/6 mice, which were randomly divided into the sham, CLP, and CLP + GYY4137 group. The indicators of SA-AKI were most prominent at 24 h after CLP, and analysis of the protein expression of ferroptosis indicators showed that ferroptosis was also exacerbated at 24 h after CLP. Moreover, the level of the endogenous H2S synthase CSE (Cystathionine-γ-lyase) and endogenous H2S significantly decreased after CLP. Treatment with GYY4137 reversed or attenuated all these changes. In the in vitro experiments, LPS was used to simulate SA-AKI in mouse renal glomerular endothelial cells (MRGECs). Measurement of ferroptosis-related markers and products of mitochondrial oxidative stress showed that GYY4137 could attenuate ferroptosis and regulate mitochondrial oxidative stress. These findings imply that GYY4137 alleviates SA-AKI by inhibiting ferroptosis triggered by excessive mitochondrial oxidative stress. Thus, GYY4137 may be an effective drug for the clinical treatment of SA-AKI.

Pharmaceutical services based on therapeutic care pathway for kidney transplantation from donors of infants and young children: a single-center experience.

Background: The pharmaceutical services based on therapeutic care pathway for kidney transplantation from infants and young children (age <3 years, weight <15 kg) to pediatric recipients can detect and resolve medication-related problems. In this paper, we report our experience on pharmaceutical services based on therapeutic care pathway to evaluate the therapeutic effects and assess the feasibility of perioperative treatment protocols. Methods: We performed a retrospective study of 12 recipients who received their graft from infants and young children, between September 2011 and December 2013 at our institution. As providers of pharmaceutical services, the clinical pharmacists collected and reviewed the clinical data from all patients, including the clinical characteristics, outcome indices, and follow-up dates. A three-step-protocol of pharmaceutical services including clinician's application, pharmacist consultation, and ongoing direct pharmaceutical care and follow-up was used through the entire length of patient's admission, hospitalization, and discharge. This protocol was developed and refined based on the guidelines for transplant perioperative treatment and experiences of the clinical pharmacists to standardize the workflow, and improve the medical treatment and quality of life of patients. Results: There was no acute rejection, graft loss, or death in 10 recipients after transplantation, and another 2 received nephrectomy due to dysfunction. Postoperative follow-up of the patients who received the pharmaceutical services from the clinical pharmacist showed an effectiveness in managing medication-related complications, patient-related factors, and an improvement of the outcomes. Conclusions: The three-step protocol of pharmaceutical services for pharmaceutical care and individual dosing regimen sponsored by pharmacists facilitated access to personalized therapies for children undergoing kidney transplantation in our hospital.

Diagnostic value of plasma tryptophan and symmetric dimethylarginine levels for acute kidney injury among tacrolimus-treated kidney transplant patients by targeted metabolomics analysis.

Few literatures have evaluated the exact role of metabolomics in the identification process of potential biomarkers for acute kidney injury among the patients receiving renal transplantation. On top of this, the success of metabolomics in biomarker translation seems to lie in the robust quantitative method. As such, a single-center retrospective observational study was conducted enrolling 42 patients underwent renal transplantation with/without acute kidney injury, as well as 24 healthy volunteers, in Shanghai Changzheng Hospital. Plasma amino acid metabolic patterns for the participants were investigated by targeted UHPLC-MS/MS metabolic profiling. The most significant changes of the explored metabolites were related to the disturbance of tryptophan metabolism and arginine metabolism. Abnormal circulating tryptophan and symmetric dimethylarginine were identified to be potential biomarkers of acute kidney injury, combination of which showed a higher area under receiver-operator curve value (AUC = 0.901), improved sensitivity (0.889) and specificity (0.831) compared with creatinine only. Overall, these results revealed that targeted metabolomics analysis would be a potent and promising strategy for identification and pre-validation of biomarkers of acute kidney injury in renal transplantation patients.

Targeted metabolomic analysis of 33 amino acids and biogenic amines in human urine by ion-pairing HPLC-MS/MS: Biomarkers for tacrolimus nephrotoxicity after renal transplantation.

Calcineurin inhibitor nephrotoxicity, especially for the widely used tacrolimus, has become a major concern in post-transplant immunosuppression. Multiparametric amino acid metabolomics is useful for biomarker identification of tacrolimus nephrotoxicity, for which specific quantitative methods are highlighted as a premise. This article presents a targeted metabolomic assay to quantify 33 amino acids and biogenic amines in human urine by high-performance liquid chromatography coupled with tandem mass spectrometry. Chromatographic separation was carried out on an Agilent Zorbax SB-C18 column (3.0 × 150 mm, 5 µm) with addition of an ion-pairing agent in the mobile phase, and MS/MS detection was achieved in both the positive and negative multiple reaction monitoring modes. Good correlation coefficients (r2 > 0.98) were obtained for most analytes. Intra- and inter-day precision, stability, carryover and incurred sample reanalysis met with the acceptance criteria of the guidance of the US Food and Drug Administration. Analysis on urine from healthy volunteers and renal transplantation patients with tacrolimus nephrotoxicity confirmed symmetric dimethylarginine and serine as biomarkers for kidney injury, with AUC values of 0.95 and 0.81 in receiver operating characteristic analysis, respectively. Additionally, symmetric dimethylarginine exhibited a tight correlation with serum creatinine, and was therefore indicative of renal function. The targeted metabolomic assay was time and cost prohibitive for amino acid analysis in human urine, facilitating the biomarker identification of tacrolimus nephrotoxicity.

Sirtinol regulates the balance of Th17/Treg to prevent allograft rejection.

BACKGROUND: Current immunosuppressive medications used after transplantation induce significant toxicity , and a new medication regimen is needed. Based on recent research, Sirt1 exerts a proinflammatory effect on the immune response. Sirtinol is a Sirt1 inhibitor, but its impact on allograft rejection and its molecular mechanisms of action have not yet been reported. RESLUTS: In this study, we examined the effect of sirtinol on prolonging allograft survival in a mouse cervical heterotopic heart transplantation model. Based on an examination of the allograft, allografts from sirtinol-treated recipients show significantly lower levels of IL-17A expression and higher levels of Foxp3 expression. In vivo, sirtinol reduces the proportion of Th17 cells and increases the proportion of Treg cells in splenocytes from recipients. In vitro, sirtinol reduces the proportion of Th17 cells and decreases the expression of IL-17A and RORγt in an isolated CD4+ T cell population. Moreover, we identified synergistic effects of sirtinol and FK506 on prolonging allograft survival, and sirtinol synergizes with FK506 to promote Foxp3 expression. CONCLUSION: Sirtinol, a Sirt1 inhibitor, may be a promising immunosuppressive drug to prevent the rejection reaction in combination with FK506.

Applied Research on Laparoscopic Simulator in the Resident Surgical Laparoscopic Operation Technical Training.

The purpose of this study was to estimate the effects of surgical laparoscopic operation course on laparoscopic operation skills after the simulated training for medical students with relatively objective results via data gained before and after the practice course of laparoscopic simulator of the resident standardized trainees. Experiment 1: 20 resident standardized trainees with no experience in laparoscopic surgery were included in the inexperienced group and finished simulated cholecystectomy according to simulator videos. Simulator data was collected (total operation time, path length, average speed of instrument movement, movement efficiency, number of perforations, the time cautery is applied without appropriate contact with adhesions, number of serious complications). Ten attending doctors were included in the experienced group and conducted the operation of simulated cholecystectomy directly. Data was collected with simulator. Data of two groups was compared. Experiment 2: Participants in inexperienced group were assigned to basic group (receiving 8 items of basic operation training) and special group (receiving 8 items of basic operation training and 4 items of specialized training), and 10 persons for each group. They received training course designed by us respectively. After training level had reached the expected target, simulated cholecystectomy was performed, and data was collected. Experimental data between basic group and special group was compared and then data between special group and experienced group was compared. Results of experiment 1 showed that there is significant difference between data in inexperienced group in which participants operated simulated cholecystectomy only according to instructors' teaching and operation video and data in experienced group. Result of experiment 2 suggested that, total operation time, number of perforations, number of serious complications, number of non-cauterized bleeding and the time cautery is applied without appropriate contact with adhesions in special group were all superior to those in basic group. There was no statistical difference on other data between special group and basic group. Comparing special group with experienced group, data of total operation time and the time cautery is applied without appropriate contact with adhesions in experienced group was superior to that in special group. There was no statistical difference on other data between special group and experienced group. Laparoscopic simulators are effective for surgical skills training. Basic courses could mainly improve operator's hand-eye coordination and perception of sense of the insertion depth for instruments. Specialized training courses could not only improve operator's familiarity with surgeries, but also reduce operation time and risk, and improve safety.

SAHA, an HDAC inhibitor, attenuates antibody-mediated allograft rejection.

BACKGROUND: Antibody-mediated rejection (AMR) is gaining increasing recognition as a critical causative factor contributing to graft loss in organ transplantation. However, current therapeutic options for prevention and treatment of AMR are very limited and ineffective. The impact of epigenetic modification in B-cell function and its involvement in AMR is still yet to be explored. METHODS: The impacts of suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor, on isolated murine B-cell viability, proliferation, apoptosis, expression of surface marker, and secretion of immunoglobulin and interleukin-10 were investigated. In vivo, a murine cardiac transplant model was used to evaluate the effect of SAHA on splenic B-cell subsets and on AMR in Rag1(-/-) recipient mice after reconstitution of allostimulated B cells. RESULTS: SAHA possesses capability to repress B-cell function. Specifically, SAHA is potent to decrease the viability of isolated B cells by inducing apoptosis. SAHA was also found capable of suppressing the expression of B-cell costimulatory molecules and, as a result, addition of SAHA into the cultures attenuated B-cell proliferation and immunoglobulin secretion. In line with these results, administration of SAHA significantly suppressed AMR in Rag1(-/-) recipient mice after reconstitution of allostimulated B cells along with enhanced cardiac allograft survival time. Mechanistic studies revealed that SAHA promotes B-cell secretion of interleukin-10. CONCLUSIONS: Our data support that SAHA could be a promising immunosuppressive agent with potential beneficial effect on prevention and treatment of AMR.

The argument for the use of mizoribine in renal transplantation: a meta-analysis and systemic review.

OBJECTIVE: The aim of this study is to evaluate the efficacy and safety of mizoribine (MZR) for immunosuppressive therapy in renal transplantation. METHODS: A systematic search of the eligible studies that compared MZR with azathioprine (AZA) for post renal transplant immunosuppressive therapy was performed by using MEDLINE, EMBASE, and the Cochrane Library. Meta-analyses were performed to study the pooled effects of relative risk (RR) and weighted mean difference with 95% confidence intervals (CI). RESULTS: A total of 486 participants from seven clinical trials were included. MZR demonstrated comparable efficacy in terms of acute rejection, patient/graft survival, and serum creatinine. However, MZR was associated with a significantly lower incidence of adverse events as compared with AZA (RR 0.39, CI 0.21-0.73, p=0.003). Specifically, recipients receiving MZR suffered from significantly fewer episodes of myelosuppression (RR 0.12, CI 0.02-0.54, p=0.006) and leukopenia (RR 0.20, CI 0.06-0.70, p=0.01). Also, MZR seemed to offer more favorable outcomes in terms of hepatic dysfunction, infection and diabetes, although the differences were not statistically significant. CONCLUSIONS: MZR is a safe, well-tolerated and effective immunosuppressive agent that can be recommended as an alternative to AZA in renal transplant recipients, although further studies are needed to balance its effect with mycophenolate mofetil.

Is it safe to withdraw steroids within seven days of renal transplantation?

BACKGROUND: The safety of very early steroid withdrawal (VESW) in renal transplant recipients remains unclear. METHODS: Literature searches for all randomized controlled trials comparing VESW with steroid maintenance regimens were performed using MEDLINE, EMBASE, and the Cochrane Library. Quality assessment was performed in each trial. Meta-analyses were performed to demonstrate the pooled effects of relative risk (RR) and weighted mean difference with 95% confidence intervals (CI). RESULTS: A total of 3520 participants from 15 RCTs were included. VESW regimen increased the incidence of acute rejection (AR) over controls (RR = 1.46, CI = 1.20-1.79, p = 0.04). Subsequent analysis demonstrated that such difference lost significance in patients receiving tacrolimus (p = 0.16), but remained significant in patients with cyclosporin (p < 0.00001). The increased AR episodes were predominantly mild. VESW was associated with an increased incidence of delayed graft function (DGF) when steroids were withdrawn within three d post-transplantation. Cardiovascular risk factors, including incidence of new onset diabetes and total cholesterol, were significantly reduced under VESW regimen. CONCLUSIONS: It is safe and practical to withdraw steroids very early after renal transplantation. However, a three- to seven-d course of steroids may decrease the risk for DGF relative to steroid withdrawal in <3 d. Antibody induction is effective in preventing early AR.

Alemtuzumab induction in renal transplantation: a meta-analysis and systemic review.

OBJECTIVE: To compare the efficacy and safety of alemtuzumab versus traditional antibodies for induction therapy in renal transplantation. METHODS: Literature searches for all randomized controlled trials comparing alemtuzumab with traditional antibodies for post renal transplant induction therapy were performed using MEDLINE, EMBASE and the Cochrane Library. Quality assessment was performed in each trial. Meta-analyses were performed to demonstrate the pooled effects of relative risk (RR) with 95% confidence intervals (CI). RESULTS: A total of 808 participants from six randomized controlled trials (RCTs) were included. Alemtuzumab was associated with lower incidence of biopsy-proven acute rejection over traditional antibodies (RR 0.63, CI 0.45-0.87, p=0.005). This difference remained when only studies comparing alemtuzumab with rabbit antithymocyte globulin were included (RR 0.32, CI 0.11-0.91, p=0.03), but lost significance when only patients at high-risk were included (RR 0.86, CI 0.48-1.55, p=0.62). No significant differences were detected between alemtuzumab and traditional antibodies in terms of delayed graft function, patient death, graft loss, and safety profile. CONCLUSIONS: Alemtuzumab induction is superior to traditional antibodies in preventing AR in renal transplantation, but this benefit may not extend to recipients at high immunologic risk. The lower rejection rates do not translate into a uniform increase in graft or patient survival.

SAHA, an HDAC inhibitor, synergizes with tacrolimus to prevent murine cardiac allograft rejection.

Suberoylanilide hydroxamic acid (SAHA), as a histone deacetylase (HDAC) inhibitor (HDACi), was recently found to exhibit an immunosuppressive effect. However, whether SAHA can synergize with calcineurin inhibitors (CNIs) to inhibit allograft rejection and its underlying mechanism remain elusive. In this study, we demonstrated the synergistic effects of SAHA and non-therapeutic dose of tacrolimus (FK506) in prolonging the allograft survival in a murine cardiac transplant model. Concomitant intragraft examination revealed that allografts from SAHA-treated recipients showed significantly lower levels of IL-17 expression, and no discernable difference for IL-17 expressions was detected between SAHA- and SAHA/FK506-treated allograft as compared with allografts from FK506-treated animals. In contrast, administration of FK506 significantly suppressed interferon (IFN)-γ but increased IL-10 expression as compared with that of SAHA-treated animals, and this effect was independent of SAHA. Interestingly, SAHA synergizes with FK506 to promote Foxp3 and CTLA4 expression. In vitro, SAHA reduced the proportion of Th17 cells in isolated CD4⁺ T-cell population and decreased expressions of IL-17A, IL-17F, STAT3 and RORγt in these cells. Moreover, SAHA enhances suppressive function of regulatory T (Treg) cells by upregulating the expression of CTLA-4 without affecting T effector cell proliferation, and increased the proportion of Treg by selectively promoting apoptosis of T effector cells. Therefore, SAHA, a HDACi, may be a promising immunosuppressive agent with potential benefit in conjunction with CNI drugs.

Urological malignancy as a complication of renal transplantation: a report of twelve clinical cases.

OBJECTIVE: To analyze the epidemiographic features of urological malignancy in renal allograft recipients (RAR) in a single center METHODS: A retrospective analysis was made on 3150 patients who received renal allografts from June 1978 until the autumn of 2006 and anti-rejection treatment for at least 3 months. RESULTS: Of the 3150 recipients, 33 (1.05%) developed malignancies, including 12 patients (0.38%; eight males and four females) with urological tumors and 21 patients with skin carcinoma, right liver lobular cystic adenocarcinoma, hepatocellular carcinoma, gastric cancer, colorectal carcinoma, ileocecal adenoma, lip cancer, nasopharyngeal carcinoma, Kaposi's Sarcoma, pulmonary lymphoma, and breast cancer. The 12 cases of urological malignancies included one case of renal cell carcinoma, one case of transplanted kidney carcinoma, two cases of bilateral pelvic transitional cell carcinoma (TCC), three cases of unilateral pelvic TCC, one case of bilateral ureter TCC, one case of unilateral ureter TCC, and three cases of bladder TCC. The age at which the diagnosis was made ranged from 48 to 66 years with a mean of 58.3 +/- 4.6 years, and the mean course of immunosuppressive therapy ranged from 26 to 120 months with a mean of 62 +/- 18 months. Of the 12 patients who developed urological malignancies, six had been on a Oyclosporine A + Azaithioprine + Prednisone (OsA + Aza + Pred) protocol; five on a Oyclosporine A + Mycophenolate Mofetil + Prednisone (OsA + MMF + Pred) protocol; and one on a Tacrolimus + Mycophenolate Mofetil + Prednisone (FK506 + MMF + Pred) protocol. One of the 12 patients died soon after the diagnosis was made, and the remaining 11 patients received surgical resection. Of them, 10 patients survived well, and the other one died from cerebral hemorrhage soon after operation. CONCLUSION: Urological malignancies, especially TCC, are an important complication in renal transplanatation found in this center. The incidence of urological malignancy in renal allograft recipients (RAR) is about 10 times that found in the general population of Shanghai versus two times for other malignancies. The occurrence of the malignancies in PAR seems to be closely related to the use of immunosuppressive agents. lmmunosuppression results in the weakening of immnuologic surveillance function, leading to mutation, aberration, and carcinogenesis. The immunological status of patients after renal transplantation should be assessed regularly. Painless macroscopic hematuria should be considered a significant sign in assessing the potential occurrence of urological malignancy in RAR. Treatment includes early diagnosis, timely surgical resection, and reduction of immunosuppressive agents.