Elevated fibrinogen to pre-albumin ratio predicts mortality in peritoneal dialysis patients.

BACKGROUND: Fibrinogen to pre-albumin ratio (FPR) is a promising predictor of mortality in various cancers. The aim of this study was to explore the prognostic value of FPR to predict mortality in peritoneal dialysis (PD) patients. METHODS: We retrospectively analyzed 324 incident PD patients form January 2011 to December 2020. Patients were stratified based on the optimal thresholds for FPR at baseline to predict overall and cardiovascular mortality during follow-up. The association of FPR and all-cause and cardiovascular mortality was evaluated by Kaplan-Meier curve and Cox regression analysis. RESULTS: All patients were divided into three groups based on the optimal cutoff value of FPR. Higher FPR levels were strongly correlated with worse overall and cardiovascular mortality in PD patients. Compared with patients in the lowest FPR tertile (<14.3), those in the highest terile (≥18.8) had multivariable-adjusted hazard ratios (95% CI confidence interval) of 3.37 (1.76-6.49) and 2.86 (1.31-6.23) for all-cause and cardiovascular mortality, respectively. Significant differences in overall survival were observed across nearly all subgroups after stratification. CONCLUSIONS: Patients with a high FPR had increased all-cause and cardiovascular mortality. FPR is a potential prognostic indicator in PD patients.

Relaxin attenuates aristolochic acid induced human tubular epithelial cell apoptosis in vitro by activation of the PI3K/Akt signaling pathway.

Aristolochic acid nephropathy remains a leading cause of chronic kidney disease (CKD), however few treatment strategies exist. Emerging evidence has shown that H2 relaxin (RLX) possesses powerful antifibrosis and anti-apoptotic properties, therefore we aimed to investigate whether H2 relaxin can be employed to reduce AA-induced cell apoptosis. Human proximal tubular epithelial (HK-2) cells exposed to AA-I were treated with or without administration of H2 RLX. Cell viability was examined using the WST-8 assay. Apoptotic morphologic alterations were observed using the Hoechst 33342 staining method. Apoptosis was detected using flow cytometry. The expression of caspase 3, caspase 8, caspase 9, ERK1/2, Bax, Bcl-2, and Akt proteins was determined by Western blot. Co-treatment with RLX reversed the increased apoptosis observed in the AA-I only treated group. RLX restored expression of phosphorylated Akt which found to be decreased in the AA-I only treated cells. RLX co-treatment led to a decrease in the Bax/Bcl-2 ratio as well as the cleaved form of caspase-3 compared to the AA-I only treated cells. This anti-apoptotic effect of RLX was attenuated by co-administration of the Akt inhibitor LY294002. The present study demonstrated H2 RLX can decrease AA-I induced apoptosis through activation of the PI3K/Akt signaling pathway.

Prognostic value of preoperative NLR, dNLR, PLR and CRP in surgical renal cell carcinoma patients.

BACKGROUND: Emerging evidences indicate that inflammation plays a crucial role in carcinogenesis and tumor progression. Inflammatory response biomarkers are recognized as promising prognostic factors for improving predictive accuracy in renal cell carcinoma (RCC). We aimed to evaluate the prognostic significance of preoperative neutrophil-to-lymphocyte ratio (NLR), derived neutrophil-to-lymphocyte ratio (dNLR), platelet-to-lymphocyte ratio (PLR) and serum C-reactive protein (CRP) in RCC. METHODS: 484 surgical RCC patients were enrolled from 2006 to 2010 in this study. Receiver operating curve (ROC) was applied to assess the optimal cutoff levels for four biomarkers, and the prognostic values were determined by Kaplan-Meier curve, univariate and multivariate COX regression models. The predictive accuracy was evaluated by concordance index (c-index). RESULTS: The median follow-up duration after surgical resection was 36 months. The optimal cutoff levels were 2.78 for NLR, 2.05 for dNLR, 185 for PLR and 5.1 for CRP by ROC curves analysis. Elevated NLR, dNLR, PLR and CRP were significantly correlated with worse overall survival (OS). Multivariate analysis showed that elevated NLR was an independent risk factor for OS, and NLR was superior to dNLR, PLR and CRP based on hazard ratio (HR 2.10, 95 % CI 1.21-3.64, P = 0.008). Additionally, the nomogram could more effectively work in predicting OS (c-index: 0.749) in surgical RCC patients. CONCLUSION: Pre-operation NLR can be considered as a potential prognostic biomarker in patients with RCC who underwent surgical resection.

Ulinastatin administration is associated with a lower incidence of acute kidney injury after cardiac surgery: a propensity score matched study.

BACKGROUND: Systemic inflammation is involved in the development of acute kidney injury (AKI) after cardiac surgery with cardiopulmonary bypass (CPB). Ulinastatin, a urinary trypsin inhibitor (UTI), possesses a variety of anti-inflammatory effects. Therefore, we hypothesized that the administration of ulinastatin would reduce the occurrence of AKI in patients undergoing cardiac surgery with CPB. METHODS: A retrospective propensity score matched analysis was used to evaluate the effect of ulinastatin on the development of AKI in patients undergoing first documented cardiac surgery with CPB between January 2008 and December 2012 in our hospital. Multiple logistic regression models were also employed to identify the association between UTI administration and development of AKI. RESULTS: A total of 2072 patients who underwent cardiac surgery with CPB met the inclusion criteria. Before propensity score matching, variables such as age, baseline creatinine, CPB duration, red blood cells transfused, and hematocrit were statistically different between the ulinastatin (UTI) group and the control group. On the basis of propensity scores, 409 UTI patients were successfully matched to the 409 patients from among those 1663 patients without UTI administration. After propensity score matching, no statistically significant differences in the baseline characteristics were found between the UTI group and the control group. The propensity score matched cohort analysis revealed that AKI and the need for renal replacement therapy occurred more frequently in the control group than in the UTI group (40.83% vs. 30.32%, P = 0.002; 2.44% vs. 0.49%, P = 0.02, respectively). However, there were no significant differences in mortality, length of intensive care unit stay, and length of hospital stay between the UTI group and the control group. Using multivariate logistic regression analysis, we found ulinastatin played a protective role in the development of AKI after cardiac surgery (odds ratio 0.71, 95% confidence interval 0.56-0.90, P = 0.005). CONCLUSIONS: This study shows that ulinastatin was associated with a lower incidence of AKI after cardiac surgery, suggesting that the administration of ulinastatin may be favorable for those patients undergoing cardiac surgery with CPB.

Association of estrogen receptor-beta (ESR2) polymorphism and cancer risk: a meta-analysis.

Estrogen signal medicated by estrogen receptor (ER), which is involved in various diseases related to steroid hormone, such as cancer. A number of association studies have focused on ESR2 polymorphisms to investigate the relationship with cancer risk. However, the results are inconsistent and inconclusive. To examine this controversy, 33 studies were enrolled for the pooled analysis for three poly-morphisms (rs3020450, rs4986938, and rs1256049) in cancer risk using odds ratios (ORs) with 95% confidence intervals (CIs). Regarding rs4986938, A allele was associated with decreased breast cancer. Ethnicity subgroup analysis observed a decreased risk in both Asian and Caucasian descendent. Regarding rs1256049, cancer type subgroup analysis revealed a significant association with increased prostate and endometrial cancer risk. rs3020450 was not associated with cancer risk in any model. Further studies for clarifying the roles of ESR2 polymorphisms in cancer risk seem of vital importance.

Relaxin Inhibits High Glucose-Induced Matrix Accumulation in Human Mesangial Cells by Interfering with TGF-ß1 Production and Mesangial Cells Phenotypic Transition.

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease (ESRD). DN is characterized by glomerular extracellular matrix accumulation, mesangial expansion, basement membrane thickening, and renal interstitial fibrosis. To date, mounting evidence has shown that H2 relaxin possesses powerful antifibrosis properties; however, the mechanisms of H2 relaxin on diabetic nephropathy remain unknown. Here, we aimed to explore whether H2 relaxin can reduce production of extracellular matrix (ECM) secreted by human mesangial cells (HMC). HMC were exposed to 5.5 mM glucose (NG) or 30 mM glucose (HG) with or without H2 relaxin. Fibronectin (FN) and collagen type IV levels in the culture supernatants were examined by solid-phase enzyme-linked immunoadsorbent assay (ELISA). Western blot was used to detect the expression of α-smooth muscle actin (α-SMA) protein. Quantitative polymerase chain reaction (qPCR) method was employed to analyze transforming growth factor (TGF)-ß1 mRNA expression. Compared with the normal glucose group, the levels of fibronectin and collagen type were markedly increased after being cultured in high glucose medium. Compared with the high glucose group, remarkable decreases of fibronectin, collagen type IV, α-smooth muscle actin, and TGF-ß1 mRNA expression were observed in the H2 relaxin-treated group. The mechanism by which H2 relaxin reduced high glucose-induced overproduction of ECM may be associated with inhibition of TGF-ß1 mRNA expression and mesangial cells' phenotypic transition. H2 relaxin is a potentially effective modality for the treatment of DN.

Predicting one-year mortality in peritoneal dialysis patients: an analysis of the China Peritoneal Dialysis Registry.

This study aims to investigate basic clinical features of peritoneal dialysis (PD) patients, their prognostic risk factors, and to establish a prognostic model for predicting their one-year mortality. A national multi-center cohort study was performed. A total of 5,405 new PD cases from China Peritoneal Dialysis Registry in 2012 were enrolled in model group. All these patients had complete baseline data and were followed for one year. Demographic and clinical features of these patients were collected. Cox proportional hazards regression model was used to analyze prognostic risk factors and establish prognostic model. A validation group was established using 1,764 new PD cases between January 1, 2013 and July 1, 2013, and to verify accuracy of prognostic model. Results indicated that model group included 4,453 live PD cases and 371 dead cases. Multivariate survival analysis showed that diabetes mellitus (DM), residual glomerular filtration rate (rGFR), , SBP, Kt/V, high PET type and Alb were independently associated with one-year mortality. Model was statistically significant in both within-group verification and outside-group verification. In conclusion, DM, rGFR, SBP, Kt/V, high PET type and Alb were independent risk factors for short-term mortality in PD patients. Prognostic model established in this study accurately predicted risk of short-term death in PD patients.

Albumin-to-alkaline phosphatase ratio as a novel prognostic indicator in patients undergoing peritoneal dialysis: a propensity score matching analysis.

Background: Though the albumin-to-alkaline phosphatase ratio (AAPR) is used as a biomarker in various diseases, little is known about its effect on outcomes after peritoneal dialysis (PD). Methods: This multicenter retrospective study comprised 357 incident PD patients stratified according to the AAPR. Propensity score matching (PSM) was performed to identify 85 patients for a well-matched comparison of all-cause and cardiovascular mortality. Using Cox regression, we performed univariate and multivariate analyses to investigate the prognostic value of the AAPR and established a Kaplan-Meier curve-predicted nomogram to estimate expected overall survival (OS). We assessed the predictive accuracy using the concordance index (c-index). Results: We found that the optimal cut-off of the AAPR to predict mortality was 0.36. In the present cohort of patients undergoing PD, a low AAPR strongly correlated with worse OS. In the multivariate analysis, the AAPR was shown to be an independent marker predicting reduced OS both before [hazard ratio (HR) 1.68, 95% confidence interval (CI) 1.08-2.60, P = 0.020] and after PSM (HR 1.96, 95% CI 1.06-3.62, P = 0.020). We also observed significant differences in OS in several subgroups, but not the group of patients with comorbidities. A nomogram was established to predict overall survival, with a c-index for prediction accuracy was 0.71 after PSM. Conclusion: AAPR has potential as an independent prognostic biomarker in patients undergoing PD.

Asiaticoside ameliorates renal ischemia/reperfusion injury by promoting CD4+CD25+FOXP3+ treg cell differentiation.

Ischemia/reperfusion injury (I/R) is the major cause of acute kidney injury, which becomes a global health problem. The effects of asiaticoside, as an anti-inflammatory drug, on renal ischemia-reperfusion injury have not been well defined. After the CD4+ cells were treated with asiaticoside, the CD4+CD25+FOXP3+ Treg cell differentiation was detected by flow cytometry. The viability and release of inflammatory factors of CD4+CD25+FOXP3+ Treg cell were detected by CCK-8 and ELISA. Renal I/R injury mice model was established, and the mice were pre-treated with asiaticoside or CD25 antibody or infused with Treg cells. The histological changes of renal tissue were evaluated by Hematoxylin-eosin, PAS, and Masson staining. The renal function markers were evaluated by colorimetry, the release of inflammatory factors was determined by ELISA. The Th17 and Treg cells in the blood and spleen were quantified by flow cytometry. The expressions of FOXP3 and RoR-γt in renal tissues were determined by western blotting. Asiaticoside promoted CD4+CD25+FOXP3+ Treg cell differentiation, increased the cell viability and down-regulated TNF-α, IL-1ß, and IL-6, while up-regulated IL-10 of CD4+CD25+FOXP3+ Treg cells. Moreover, asiaticoside ameliorated the histological damage, decreased the Th17 cells and increased Treg cells, and down-regulated the TNF-α, IL-1ß, IL-6, blood urea nitrogen, serum creatinine, and RoR-γt, while up-regulated IL-10 and FOXP3 of renal I/R injury mice. Effect of asiaticoside on renal I/R injury mice was reversed by CD25 antibody whose role was further reversed by Treg cell infusing. In conclusion, asiaticoside ameliorated renal I/R injury due to promoting CD4+CD25+FOXP3+ Treg cell differentiation.

Effect of external therapies of traditional Chinese medicine on constipation in patients with CRF: A meta-analysis.

OBJECTIVE: The purpose of this study was to evaluate the curative effect of external therapies of traditional Chinese medicine on constipation in patients with chronic renal failure and to provide scientific theoretical basis for clinical practice. METHOD: We searched the English database of PubMed, EMBASE, the Cochrane Library and the Web of Science and Chinese database of CNKI, Wan fang database, VIP Database and China Biomedical Literature Database up to December 2022. Randomized controlled trials (RCTs) involving constipation in patients with CRF that compared external therapies of traditional Chinese medicine and routine treatment to routine treatment were eligible for the analysis. A meta-analysis of the outcome indicators including total efficiency, weekly defecation times, defecation time, defecation difficulty score, patient-assessment of constipation quality of life and adverse events of treatment were performed. The analysis was performed by using Review Manager version 5.3. RESULT: A total of 23 studies were included, with 1764 patients. Meta-analysis results showed that compared with the control group, the test group could significantly increase weekly defecation times(MD = 0.94, 95%CI(0.70, 1.18), Z = 7.74, P < 0.00001), reduce defecation time(MD = -2.92, 95%CI(-3.69, -2.16), Z = 7.49, P < 0.00001), reduce defecation difficulty score(MD = -1.92, 95%CI(-2.45, -1.39), Z = 7.11, P < 0.00001), improve the quality of life in patients with constipation(MD = -7.57, 95%CI(-10.23, -4.91), Z = 5.58, P < 0.00001) and obtain a higher total effective rate of treatment(OR = 4.53, 95%CI(3.27, 6.29), Z = 9.07, P < 0.00001). In terms of safety, there was no statistical significance in the incidence of adverse events between two groups(OR = 0.35, 95%CI(0.04, 2.95), Z = 0.96, P = 0.34). CONCLUSION: The combination of external therapies of traditional Chinese medicine and routine treatment could achieve an excellent curative effect, and there was no specific adverse event. However because of the limited level of current evidence, more high-quality trials are needed in the future.5.

Protective effects of asiaticoside on renal ischemia reperfusion injury in vivo and in vitro.

Ischemia/reperfusion injury (I/R) is the main causes of acute kidney injury (AKI), which is a global health concern. Evidence suggests that asiaticoside plays vital roles on anti-inflammatory and, anti-kidney fibrosis effects, and promotes tissue repair. However, the effects of asiaticoside on AKI caused by ischemia-reperfusion have not been well defined. Herein, we explored the protective effect of asiaticoside on renal ischemia-reperfusion injury (IRI) using in vivo and in vitro studies, and elucidated the potential mechanism of asiaticoside-mediated repair. Results showed that asiaticoside attenuated the levels of blood urea nitrogen (BUN) and serum creatinine (Scr) in the IRI model. Meanwhile, asiaticoside reduced the secretion of IL-6, IL-1ß and TNF-α, but increased IL-10 secretion in a dose-dependent manner. Treating Raw264.7 cells with lipopolysaccharide (LPS) induced an inflammatory response, but the LPS-induced effects were attenuated after administering asiaticoside. Furthermore, asiaticoside significantly inhibited the expression of inducible Nitric Oxide Synthase (iNOS) and promoted the expression of Arginase1 induced by LPS, which are the polarization marker proteins. In conclusion, this study shows that asiaticoside possesses protective action in AKI after ischemia-reperfusion, due to the inhibition of inflammatory mediators and promoting transformation of macrophages from M1 type to M2 type.

Exosome from indoleamine 2,3-dioxygenase-overexpressing bone marrow mesenchymal stem cells accelerates repair process of ischemia/reperfusion-induced acute kidney injury by regulating macrophages polarization.

BACKGROUND: Ischemia-reperfusion injury (IRI)-induced acute kidney injury (AKI) can repair itself completely. However, most moderate and severe patients undergoing IRI-AKI progress to chronic kidney disease due to incomplete repair. The present study is aimed to investigate the role of bone marrow mesenchymal stem cell-derived exosomes (MSC-Exo) with indoleamine 2,3-dioxygenase (IDO) overexpression on incomplete repair in mice after IRI. METHODS: IRI mice was established by clamping the unilateral renal pedicles and challenged with MSC-Exo. Blood biochemical indexes and inflammation factors contents were measured by ELISA assay. Histopathological examinations were monitored by HE, Masson, Immunohistochemical and TUNEL staining. Immunofluorescence, flow cytometry and immunoblotting were used to detect the polarization of macrophages, respectively. RESULTS: As compared to sham operation mice, IRI mice showed high contents of serum BUN and Scr, and more severe damaged kidney tissues on days 1 and 3, which all gradually declined over time, showing the lowest level on day 7 after injury. Once treated with MSCs-Exo that could directly transfer to kidney tubular cells, the restoration of kidney functions significantly accelerated by contrast to IRI mice, and the promotive effects were more obvious in IDO-overexpressed MSCs-Exo (MSCs-Exo-IDO)-treated IRI mice. Furthermore, MSCs-Exo-IDO administration also accelerated renal tubular cells proliferation, restrained tubular cells apoptosis, fibrosis and inflammation factor secretions during self-repair process compared to IRI mice, whose effects were higher than MSCs-Exo-NC-challenged IRI mice and IDO overexpressing plasmid-injected IRI mice. Mechanistically, MSCs-Exo-NC and MSCs-Exo-IDO exposure promoted the polarization from M1 macrophage to M2 macrophage, leading to more anti-inflammatory factors production, and subsequently altered the inflammatory microenvironment of renal tubular cells, which facilitated the self-repair process in mice after IRI. CONCLUSION: MSCs-derived exosome accelerated renal self-repair in IRI mice by activating M2 macrophages polarization, which effects were amplified by IDO overexpression in MSCs. Potentially, genetically modified MSCs-Exo is an effective approach to improve renal self-repair in IRI-AKI mice.

Mining bacterial NGS data vastly expands the complete genomes of temperate phages.

Temperate phages (active prophages induced from bacteria) help control pathogenicity, modulate community structure, and maintain gut homeostasis. Complete phage genome sequences are indispensable for understanding phage biology. Traditional plaque techniques are inapplicable to temperate phages due to their lysogenicity, curbing their identification and characterization. Existing bioinformatics tools for prophage prediction usually fail to detect accurate and complete temperate phage genomes. This study proposes a novel computational temperate phage detection method (TemPhD) mining both the integrated active prophages and their spontaneously induced forms (temperate phages) from next-generation sequencing raw data. Applying the method to the available dataset resulted in 192 326 complete temperate phage genomes with different host species, expanding the existing number of complete temperate phage genomes by more than 100-fold. The wet-lab experiments demonstrated that TemPhD can accurately determine the complete genome sequences of the temperate phages, with exact flanking sites, outperforming other state-of-the-art prophage prediction methods. Our analysis indicates that temperate phages are likely to function in the microbial evolution by (i) cross-infecting different bacterial host species; (ii) transferring antibiotic resistance and virulence genes and (iii) interacting with hosts through restriction-modification and CRISPR/anti-CRISPR systems. This work provides a comprehensively complete temperate phage genome database and relevant information, which can serve as a valuable resource for phage research.

miR-30a-5p targets Becn1 to ameliorate high-glucose-induced glomerular podocyte injury in immortalized rat podocyte cell line.

OBJECTIVE: Diabetic nephropathy (DN) is a serious kidney-based complication of diabetes, wherein podocyte injury is deemed crucial in the development of early stage. Various miRNAs, as report goes, is involved in the pathogenesis of varieties of kidney diseases including DN. In this study, we found a target relationship between miR-30a-5p and Becn1, of which there are few studies about the role in podocyte injury. We therefore used immortalized rat podocyte cell line to explore the role and molecular mechanism of miR-30a-5p targeting Becn1 gene in high-glucose-induced glomerular podocyte injury. METHODS: The mRNA and protein expressions of miR-30a-5p and Becn1 were detected respectively by quantitative reverse transcriptase PCR and western blotting. The proliferation, apoptosis, and the levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-α were detected by MTT assay, flow cytometry, and enzyme-linked immuno sorbent assay, respectively. Intracellular reactive oxygen species (ROS), superoxide dismutase (SOD) and malondialdehyde (MDA) levels were also determined. RESULTS: Compared with normal group, miR-30a-5p in model groups were down-regulated, while Becn1 expression was significantly up-regulated, with slower proliferation, higher apoptosis rate, lower SOD level, and significantly higher ROS, MDA, IL-6, and TNF-α levels (all P<0.05). Overexpression of miR-30a-5p or Becn1 knock-out could lower Becn1 expression, apoptosis rate, promote proliferation, with relatively higher SOD level and lower ROS, MDA, Il-6, and TNF-α levels of model cells (all P<0.05). CONCLUSION: Up-regulation of miR-30a-5p can suppress the expression of Becn1 to increase the growth and inhibit the apoptosis of immortalized rat podocyte cell line, therefore ameliorating podocyte injury induced by high glucose in vitro.

Multicenter Investigation of the Initial Hemodialysis Vascular Access and Its Related Factors in Hangzhou of China.

OBJECTIVE: To investigate the initial hemodialysis vascular access in Hangzhou and provide evidence for improving the use of autologous arteriovenous fistula by identifying factors associated with the choice of initial vascular access. METHODS: We retrospectively studied the initial hemodialysis vascular access of 257 patients in five hemodialysis units in Hangzhou of China during a 21-month period (January 2018 to September 2019). A logistic regression was used to identify the risk factors of failing to use an arteriovenous fistula at the initiation of hemodialysis. RESULTS: (1) 257 participants with mean age 67.65 ± 13.43 years old were reviewed, including 165 males (64.2%) and 92 females (35.8%). The etiologies of end-stage renal disease included diabetic nephropathy (37.35%), chronic glomerulonephritis (31.13%), hypertensive nephropathy (14.01%), and other diseases (17.51%). Only 51 patients (19.84%) received arteriovenous fistula, whereas the remaining 206 patients (80.16%) initiated dialysis with a central venous catheter. (2) Logistic regression analysis revealed that the independent risk factors for central venous catheter at the initial hemodialysis were age >70 years old (OR = 4.827, p < 0.01 versus ≤70 years old), chronic glomerulonephritis as the primary etiology (OR = 2.565, p < 0.05 versus nonchronic glomerulonephritis) and eGFR <8.5 mL/min/1.73m2 (OR = 2.283, p < 0.05 versus eGFR ≥8.5 mL/min/1.73m2). CONCLUSION: The proportion of patients using arteriovenous fistula as the initial hemodialysis vascular access in Hangzhou was still low. The choice of vascular access for the first hemodialysis was related to age, eGFR, and the primary etiology of end-stage renal disease. Increasing the proportion of planned vascular access and arteriovenous fistula at the initiation of hemodialysis is still our current goal.

Trib1 Contributes to Recovery From Ischemia/Reperfusion-Induced Acute Kidney Injury by Regulating the Polarization of Renal Macrophages.

Increasing evidence suggests that macrophage polarization is involved in the recovery from ischemia-reperfusion (I/R)-induced acute kidney injury (AKI), implying that the regulation of macrophage polarization homeostasis might mediate AKI recovery. Trib1 is a key regulator of macrophage differentiation, but its role in AKI remains unclear. Here, we aimed to investigate the role of Trib1 and its link with the macrophage phenotype in the process of adaptive recovery from I/R-induced renal injury. Lentiviral vector-mediated RNA interference (RNAi) was used to knock down Trib1 expression in vitro and in vivo, and a mouse model of moderate AKI was established by the induction of I/R injury. Renal function measurements and inflammatory factors were determined by the corresponding kits. Histomorphology was assessed by hematoxylin-eosin, Masson and PAS staining. Western blot and flow cytometry were employed for the analysis of signal transduction, cell apoptosis and macrophage phenotypes. Trib1 knockdown inhibited cell viability of tubular epithelial cells (TECs) by inhibiting proliferation and enhancing apoptosis in vitro. I/R-induced AKI significantly impaired renal function in mice via increasing the levels of BUN, Scr, NGAL and renal tubular damage, leading to renal fibrosis from days 1 to 3. Through the adaptive self-repair mechanism, renal dysfunction recovered over time and returned to almost normal levels on day 28 after I/R intervention. However, Trib1 depletion worsened renal damage on day 3 and blunted the adaptive repair process of the renal tissue. Mechanistically, Trib1 inhibition suppressed renal tubular cell proliferation under adaptive self-repair conditions by affecting the expression of the proliferation-related proteins cyclin D1, cyclin B, p21, and p27, the apoptosis-related proteins Bcl-2 and Bax, and the fibrosis-related proteins collagen I and III. Furthermore, the M1/M2 macrophage ratio increased in the first 3 days and decreased from day 7 to day 28, consistent with changes in the expression of inflammatory factors, including TNFα, IL-6, IL-12, IL-10, and IL-13. Trib1 inhibition blocked macrophage polarization during adaptive recovery from I/R-induced moderate AKI. Our results show that Trib1 plays a role in kidney recovery and regeneration via the regulation of renal tubular cell proliferation by affecting macrophage polarization. Thus, Trib1 might be a viable therapeutic target to improve renal adaptive repair following I/R injury.

Protective role of relaxin in a mouse model of aristolochic acid nephropathy.

BACKGROUND: Aristolochic acid nephropathy (AAN) is a chronic, progressive interstitial nephritis. To date, treatment strategies remain limited. Mounting evidence shows that relaxin (RLX) possesses powerful anti-fibrotic and anti-apoptotic characteristics, therefore, the present study aimed to investigate the possible protective role of RLX in aristolochic acid (AA) induced nephrotoxicity. METHODS: The in vitro cell tests were performed: the embryonic kidney cells 293 were treated with AA-I (40 µg/mL) or with AA-I (40 µg/mL) plus RLX (100 ng/mL) and the cell groups were then tested and the normal 293 cells were set as blank control. In addition, the in vivo animal tests were performed: mice were randomly divided into three groups: a control group injected intraperitoneally with an equal volume of saline every other day for 6 weeks, an AA group injected intraperitoneally with AA-I (5 mg/kg) every other day for 6 weeks, and an AA + RLX group treated with the AA-I for 6 weeks and subsequently received RLX (0.25 mg/kg/day) using an implanted osmotic mini-pump for an additional 2 weeks. 8 weeks post-AA-I, mice were sacrificed for analysis. RESULTS: In the in vivo animal tests, RLX administration prevented increased plasma creatinine and nitrogen levels caused by aristolochic acid as well as alleviated the severity of renal ultrastructural lesions induced by aristolochic acid. Both in the in vitro cell tests and in the in vivo animal tests, Western blotting of the AA-I group showed increased expression of the pro-apoptotic protein genes Bax and the cleaved form of caspase-3, both of which were reversed by RLX. In contrast, the expression of the anti-apoptotic gene Bcl-2 correlated inversely to Bax in RLX treated mice. RLX restored the decreased phosphorylated Akt induced by AA-I. The protein expression of eNOS was also reduced in AA-I treated group compared with control, which was reversed in the presence of RLX. Immunohistochemical staining of the animal tissue revealed that RLX markedly reduced the overexpression of type IV collagen, fibronectin, and alpha-smooth muscle actin in AA-I treated mice. CONCLUSIONS: Our results suggest that RLX alleviates AA-I induced kidney fibrosis by reducing apoptosis and up-regulation the expression of p-Akt.

Relaxin Attenuates Contrast-Induced Human Proximal Tubular Epithelial Cell Apoptosis by Activation of the PI3K/Akt Signaling Pathway In Vitro.

Background. Contrast-induced acute kidney injury (CI-AKI) is one of the main causes of iatrogenic acute kidney injury (AKI); however, therapeutic strategies for AKI remain limited. This study aims to explore the effect of relaxin (RLX) on contrast-induced HK-2 apoptosis and its underlying mechanisms. Methods. Renal tubular epithelial cells (HK-2) were incubated either with or without ioversol, human H2 relaxin, and LY294002 (the inhibitor of the PI3K/Akt signal pathway). Cell viability was evaluated with a CCK-8 assay. Apoptotic morphologic alterations were observed using the Hoechst 33342 staining method. Apoptosis was detected with Annexin V staining. Western blot analysis was employed to measure the expression of pAkt (S473), Akt, cleaved caspase-3, Bcl-2, Bax, and actin proteins. Results. Ioversol reduced the viability of HK-2 cells. Western blotting results revealed decreased expression of phosphorylated Akt in cells treated with ioversol. The activities of caspase-3 and Bax protein increased, while the expression of Bcl-2 protein decreased. As a result, the Bax/Bcl-2 ratio increased after treatment with ioversol. These effects were reversed when HK-2 cells were cotreated with RLX. However, with preadministration of PI3K/Akt pathway inhibitor LY294002, the effect of RLX was blocked. Conclusion. Our study demonstrates that relaxin attenuates ioversol induced cell apoptosis via activation of the PI3K/Akt signaling pathway, suggesting that RLX might play a protective role in the treatment of CI-AKI.

Reassessment of Acute Kidney Injury after Cardiac Surgery: A Retrospective Study.

Objective To evaluate the incidence, risk, or protective factors of acute kidney injury (AKI) in patients after cardiac surgery based on the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Methods A retrospective analysis of 2,575 patients undergoing their first documented cardiac surgery with cardiopulmonary bypass (CPB) was conducted. Perioperative variables were collected and analyzed. Univariate and multiple logistic regression models were used for determining the association between the development of AKI and risk factors. Multiple Cox-proportional hazards modeling was performed to evaluate the impact of AKI on the mortality in the intensive care unit and hospital length of stay. Results Of 2,575 patients, 931 (36%) developed AKI. A total of 30 (1.2%) patients required renal replacement therapy. In the multivariate analysis, mechanical ventilation duration (OR1.446, 95% CI 1.195-1.749, p<0.001), CPB duration of ≥110 min (OR 1.314, 95% CI 1.072-1.611, p=0.009), erythrocytes transfusion (OR 1.078, 95% CI 1.050-1.106, p<0.001), and postoperative body temperature greater than 38°C within 3 days (OR 1.234, 95% CI 1.018-1.496, p=0.032) were independent risk factors for CSA-AKI, while ulinastatin use was associated with a reduced incidence of CSA-AKI (OR 0.694, 95% CI 0.557-0.881, p=0.006). CSA-AKI was significantly associated with in-hospital mortality (adjusted HR: 2.218, 95% CI 1.161-4.238, p=0.016), especially in patients needing renal replacement therapy (adjusted HR: 18.683, 95% CI 8.579-40.684, p<0.001). Conclusion Mechanical ventilation duration, erythrocytes transfusion, and postoperative body temperature above 38°C within 3 days were considered independent risk factors for CSA-AKI. The use of ulinastatin was associated with a reduced incidence of CSA-AKI.

Effects of Low-Protein Diets Supplemented with Ketoacid on Expression of TGF-ß and Its Receptors in Diabetic Rats.

TGF-ß 1 has been recognized as a key mediator in DN. This study aimed to observe the effects of low-protein diets supplemented with ketoacid on mRNA and protein expression of TGF-ß and TßRI and t TßRII receptors in the renal tissue of diabetic rats. A diabetes model was established in 72 male SD rats. They were then equally randomized to three groups: NPD group, LPD group, and LPD + KA group. Additional 24 male SD rats receiving normal protein diets were used as the control. Eight rats from each group were sacrificed at weeks 4, 8, and 12 after treatment, from which SCr, BUN, serum albumin, and 24 h urinary protein excretion were collected. The expressions of TGF-ß 1, TßRI, and TßRII in LPD and LPD + KA groups were significantly lower than those in NPD group and lower in LPD + KA group than those in LPD group. Low-protein diets supplemented with ketoacid have been demonstrated to provide a protective effect on the renal function as represented by reduced SCr, BUN, and urinary protein excretion, probably through downregulating the gene expression of TGF-ß 1 and its receptors in LPD + KA group.