Xiaopeng Yuan

Triptolide attenuates renal interstitial fibrosis in rats with unilateral ureteral obstruction.

Aim:  Extracts of Tripterygium wilfordii Hook F. have been used to treat glomerulonephritis for more than 30 years in China. Most of the anti‐inflammatory and immunosuppressive activities of these extracts can be attributed to triptolide (Trip). The present study was to investigate the effect of Trip on renal interstitial fibrosis in a model of unilateral ureteral obstruction (UUO).

Effects of Ligustrazine on Ureteral Obstruction‐induced Renal Tubulointerstitial Fibrosis

Ligustrazine (LIG) is a purified and chemically identified component of the Chinese herb Ligusticum wallichii Franchat. It is a potent blocker of vasoconstriction and has strong scavenger of oxygen free radicals. We investigated the effect of LIG on renal tubulointerstitial fibrosis using a rat model of unilateral ureteral obstruction. Ligustrazine treatment significantly reduced the scores of interstitial collagen deposition, amounts of hydroxyproline, the density of myofibroblasts and macrophages, and amounts of transforming growth factor‐β1 (TGF‐β1) and connective tissue growth factor (CTGF) compared with their level in a saline‐treated control group. Using quantitative polymerase chain reaction we found that LIG treatment significantly reduced the mRNA expression of TGF‐β1, CTGF, monocyte chemoattractant protein‐1 and osteopontin. Moreover, the mRNA expression of hepatocyte growth factor and bone morphogenetic protein‐7 were significantly increased by LIG. In vitro, LIG inhibited the TGF‐β1‐induced loss of cytokeratin‐18 expression and de novo increase of the expression of α‐smooth muscle actin of HK‐2 cells in a dose‐dependent manner, which suggested that LIG could restrain the process of epithelial‐myofibroblast transition of tubular epithelial cells. This study indicates that LIG can attenuate renal tubulointerstitial fibrosis. It might be useful as a potential candidate in the treatment of chronic renal diseases. Copyright

Pretreatment of Transfused Donor Splenocytes and Allografts With Mitomycin C Attenuates Acute Rejection in Heart Transplantation in Mice

OBJECTIVE The aim of this study was to investigate the effect of pretreatment of donor splenocytes and grafts with mitomycin C (MMC) on heart allograft survival, as well as to demonstrate the mechanism of function. METHODS Donor splenocytes from Balb/C mice were incubated with MMC (40 μg/mL) in vitro and then transfused into recipients (C57BL/6 mice). The heart allograft was perfused with MMC before harvest. Graft survival and histopathology were examined. Lymphocyte activation, regulatory T cells, and donor splenocyte apoptosis were examined with the use of flow cytometry. RESULTS MMC incubation in vitro induced apoptosis of donor splenocytes (15.5 ± 2.3% vs 23.2 ± 4.2%; P < .01). Either intravenous injection of MMC-treated donor splenocytes or transplantation of allograft pretreated with MMC prolonged heart allograft mean survival time from 7 ± 0.8 days to 20.5 ± 1.9 days or 10 ± 0.9 days, respectively (both P < .01). A combination of MMC-pretreated donor splenocyte transfusion and allografts showed the best effect on prolongation of graft survival (28.5 ± 1.8 days). Activation of CD4(+) T cells in spleen and peripheral lymph nodes of recipients was significantly inhibited by either MMC-splenocyte transfusion or the combination treatment. Meanwhile, the percentage of CD4(+)CD25(+)Foxp3(+) regulatory T cells in the spleen was increased in the MMC-splenocyte transfusion group (15.5 ± 1.1% vs 18.2 ± 0.9%; P < .05). CONCLUSIONS Both injection of MMC-conditioned donor splenocytes and MMC-conditioned allograft have effects on prolongation of heart allograft survival in mice, and MMC-conditioned donor splenocytes might play an essential role. MMC pretreatment induced regulatory T cells likely through induction of donor splenocyte apoptosis, and thus it inhibited T-cell activation.

MicroRNA-34a regulates liver regeneration and the development of liver cancer in rats by targeting Notch signaling pathway

Objective This study aimed to investigate the role of microRNA-34a (miR-34a) in regulating liver regeneration (LR) and the development of liver cancer in rats by targeting Notch signaling pathway. Methods Thirty male Sprague-Dawley (SD) rats were randomly assigned into partial hepatectomy (PH) group and sham hepatectomy (SH) group. Hematoxylin and eosin (HE) staining was used to observe the histological change in liver tissues. Enzyme-linked immunosorbent assay (ELISA) was used to measure the serum tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) levels. Dual-luciferase reporter gene assay was performed to examine whether miR-34a targeted Notch1 gene. Human liver cancer Huh7 cells were transfected and divided into blank, negative control (NC), miR-34a mimics and miR-34a inhibitors groups. MTT and flow cytometry were used to detect cell growth, and cell cycle and apoptosis, respectively. Quantitative real-time polymerase chain reaction (qRT-PCR) was applied detect to the expressions of miR-34a and Notch receptor mRNA. Western blotting was performed to detect the protein expressions of Notch receptors, P21, Bax, Bcl-2 and Bcl-xL. Tumor xenograft in nude mice was done to observe tumor formation in different groups. Results Compared to the SH group, miR-34a expression in liver tissues in the PH group decreased first and then increased to the normal level during LR. In early stage of LR, the expressions of Notch receptors and miR-34a were negatively correlated. Compared to the blank and NC groups, the cell growth was inhibited, cell cycle was mainly arrested in the G2/M phase and cell apoptosis rate increased in the miR-34a mimics group. Moreover, the expressions of miR-34a, P21 and Bax were up-regulated, while the expressions of Notch receptors, and Bcl-2 and Bcl-xL were down-regulated in this group. Additionally, the tumor growth in the miR-34a mimics group was reduced. The miR-34a inhibitors group showed contrary tendencies. Conclusion Our study demonstrates that miR-34a regulated LR and the development of liver cancer by inhibiting Notch signaling pathway.

En Bloc Dual Kidney Transplantation from Pediatric Donors after Cardiac Death: Initial Experience in China

Objective: To report 9 cases of en bloc kidney transplantation from pediatric donors in China and share the clinical experience. Methods: From February 2010 to February 2014, 9 pediatric donors (aged 5 months to 6 years) were assigned to us by the modern donation and allocation system after cardiac death. The en bloc kidneys were recovered in all 9 patients. The inferior vena cava and aorta of the donors were anastomosed to the external vein and artery of the recipients (7 adults and 2 children). Alprostadil or enoxaparin sodium was used for anticoagulation. Results: The kidneys attained immediate perfusion after vascular anastomosis, except for one renal artery that developed thrombosis several minutes later, necessitating nephrectomy of the unilateral graft. The other eight en bloc grafts maintained normal function during the follow-up period of 1-50 months and all the patients survived. There were no rejections or other complications. Based on ultrasonography, the grafts increased in size during the follow-up period. Conclusions: These results indicate that en bloc renal transplantation from pediatric donors is an acceptable procedure, and more widespread use could increase the number of potential donors. Splitting of pediatric donor en bloc kidneys for transplantation into two recipients may also be feasible in well-matched cases.

Ginkgo biloba extract EGb761 attenuates brain death-induced renal injury by inhibiting pro-inflammatory cytokines and the SAPK and JAK-STAT signalings

This study aimed to investigate the protective effects of EGb761, a Ginkgo Biloba extract, against brain death-induced kidney injury. Sixty male Sprague Dawley rats were randomly divided into six groups: sham, brain-death (BD), BD + EGb b48h (48 hours before BD), BD + EGb 2 h (2 hours after BD), BD + EGb 1 h, and BD + EGb 0.5 h. Six hours after BD, serum sample and kidney tissues were collected for analyses. The levels of blood urea nitrogen (BUN) and serum creatinine significantly elevated in the BD group than in sham group. In all the EGb761-treated BD animals except for the BD + Gb 2 h group, the levels of BUN and serum creatinine significantly reduced (all P < 0.01). EGb761 attenuated tubular injury and lowered the histological score. In addition, the longer duration of drug treatment was, the better protective efficacy could be observed. EGb761 significantly reduced IL-1β, IL-6, TNF-α, MCP-1, IP-10 mRNA expression and macrophage infiltration in the kidney. EGb761 treatment at 48 hour before brain death significantly attenuate the levels of p-JNK-MAPK, p-p38-MAPK, and p-STAT3 proteins (all P < 0.05, compared to BD group). In summary, our data showed that EGb761 treatment protected donor kidney from BD-induced damages by blocking SAPK and JAK-STAT signalings. Early administration of EGb761 can provide better protective efficacy.

MicroRNA-423-5p facilitates hypoxia/reoxygenation-induced apoptosis in renal proximal tubular epithelial cells by targeting GSTM1 via endoplasmic reticulum stress

It has been reported that microRNAs (miRs) can regulate renal response to acute injury and members of them are believed to be important in maintenance of renal function and development of renal injury. We investigated the actions of microRNA-423-5p (miR-423-5p) and glutathione-S-transferase (GST) M1 after acute kidney injury. MiR-423-5p was up-regulated and GSTM1 was down-regulated in human kidney (HK-2) cells subjected to hypoxia/reoxygenation (H/R) and in rat kidneys subjected to ischemia/reperfusion (I/R) injury. Dual luciferase assays revealed miR-423-5p binding to the 3′ untranslated region of GSTM1. Proliferation was lower and apoptosis, ER stress and oxidative stress were all higher in H/R-treated HK-2 cells transfected with or without miR-423-5p mimics and GSTM1 siRNA than in the same cells transfected with miR-423-5p inhibitors and a GSTM1 expression vector. Increased miR-423-5p and decreased GSTM1 mRNA and protein levels were observed in rat kidneys on days 1, 2 and 7 after I/R. Levels had normalized by days 14 and 21. On day 3 after treatment, rats receiving I/R or I/R plus miR-423-5p mimics exhibited higher serum creatinine and urea nitrogen levels than rats receiving I/R plus a miR-423-5p inhibitor. MiR-423-5p and lower GSTM1 mRNA and protein levels were higher in the I/R and I/R plus miR-423-5p mimic groups than in the I/R plus miR-423-5p inhibitors group. These findings demonstrate that after acute kidney injury, miR-423-5p induces ER stress and oxidative stress by inhibiting GSTM1and suppresses repair.

Suppression of alloimmunity in mice by regulatory T cells converted with conditioned media.

BACKGROUND Compared with rare CD4+CD25+ regulatory T cells (Tregs), CD4+CD25- T cells are abundant in peripheral blood. Studies have demonstrated that tumors can convert naive CD4+CD25- T cells into CD4+CD25+Foxp3+ Tregs; however, the potential application of the converted Tregs in transplant medicine has not well demonstrated. MATERIALS AND METHODS CD4+CD25- T cells isolated cultured for 5 d in various combinations of cell culture medium and conditioned medium from RenCa cells. Foxp3 levels were determined by flow cytometry and real-time polymerase chain reaction. BALB/c mouse mononuclear cells (responder) combined with different ratios of the converted CD4+CD25+ Tregs were co-cultured with inactivated C57BL/6 mononuclear cells (stimulator) in one-way mixed lymphocyte reaction (MLR). In addition, the converted Tregs were transferred into a mouse skin transplant model, and graft histology, survival time, and delayed-type hypersensitivity were assessed. RESULTS CD4+CD25- T cells cultured in media supplemented with increasing concentrations of RenCa conditioned medium were partially converted into CD4+CD25+ Tregs; conversion increased as the percentage of conditioned medium increased. Moreover, the converted CD4+CD25+ Tregs possessed characteristics similar to those of naturally occurring Tregs, including Foxp3 expression and the ability to suppress T cell proliferation in one-way MLR in a concentration-dependent manner. Immunosuppressive effects of the converted CD4+CD25+ Tregs were also similar to those of naturally occurring Tregs in vivo, suppressing allograft rejection and prolonging survival time of allogeneic skin grafts following adoptive transfer in mice (P<0.05). CONCLUSION Our findings indicate that CD4+CD25- T cells cultured with conditioned media from tumor cells may be useful for obtaining sufficient numbers of Tregs, which may help suppress acute rejection and prolong graft survival.

Comparison of outcomes of kidney transplantation from donation after brain death, donation after circulatory death, and donation after brain death followed by circulatory death donors

There are three categories of deceased donors of kidney transplantation in China, donation after brain death (DBD), donation after circulatory death (DCD), and donation after brain death followed by circulatory death (DBCD) donors. The aim of this study was to compare the outcomes of kidney transplantation from these three categories of deceased donors.

Kidney Transplantation From Donors After Brain or Cardiac Death in China—A Clinical Analysis of 94 Cases

BACKGROUND We analyzed outcomes of kidney transplantation (KTx) from donation after brain death (DBD) or cardiac death (DCD) in China under the current level of the health care system. METHODS Among 94 KTx performed from February 2007 to March 2012 in two organ transplant centers in the south of China, 50 KTx were used DBD and 44 DCD donors. We retrospectively analyzed the clinical outcomes. RESULTS At a mean follow-up of 25.5 months, the 1-year and 2-year graft survival rates were 96.8% and 95.2% respectively. Delayed graft function (DGF) occurred in 27.7% recipients, three of whom lost graft function. Among six observed acute rejection episodes, five were reversed. When compared to the DCD group in DBD patients were apt to recover from DGF. Serum creatinine decreased more promptly in the DBD than in DCD group. Serum creatinine in the DCD group increased after months 12, when it was significantly higher than that in the DBD group (P < .05). CONCLUSIONS Kidney transplantation from DBD donors showed good outcomes with few complications. Although KTx from DCD donors showed a higher DGF rate and longer duration of graft recovery, we achieved favorable short-term clinical outcome using this source.