Immune Infiltration Landscape on Identified Molecular Subtypes of Chronic Kidney Disease.

Immune imbalance has become an important factor in the progression of chronic kidney disease (CKD). Molecular typing of CKD may be key to achieving precise treatment. xCell allows immune cell phenotyping in CKD. We integrated two independent microarray datasets and divided 87 CKD patients into two subgroups using unsupervised consensus clustering to study the correlation between CKD and patient sex, age, and CKD stage. We found different expression patterns and clinical characteristics between the two groups. CKD stage was more advanced in cluster I than in cluster II, and the weighted gene coexpression network analysis module characteristics showed enrichment of interferon and leukocyte-associated immune pathways in cluster I. Differentially expressed gene analysis revealed the 12 most significantly changed genes, of which sirtuin 1 (SIRT1) was significantly downregulated in cluster I. Gene set enrichment analysis identified multiple immune-related processes involved in CKD. xCell immune infiltration analysis revealed the significant upregulation of natural killer T (NKT) cells and the significant downregulation of most T and B cell types in cluster I. SIRT1 showed a significant negative correlation with NKT cell infiltration but a positive correlation with CD4+ T cell and natural killer cell infiltration. We systematically studied the molecular typing of the CKD transcriptome and estimated the degree of immune cell infiltration based on molecular subtypes. Our results indicate that different subgroups may have unique gene expression patterns and immune dysregulation patterns, thus providing a basis for precise treatment and immune research in CKD.

Valsartan Alleviates Insulin Resistance in Skeletal Muscle of Chronic Renal Failure Rats.

BACKGROUND Studies on insulin resistance (IR) in chronic kidney disease (CKD) patients are rare, and its exact mechanism remains unclear. In this study, we explored the molecular mechanism of IR with chronic renal failure (CRF) and interventions to alleviate IR in patients with CRF. MATERIAL AND METHODS In vivo and in vitro models of CRF were established by 5/6 nephrectomy and urea stimulation C2C12 cells, respectively. Based on the CRF model, angiotensin II (Ang II) and valsartan groups were established to observe the effect of drug intervention on IR. Western blot assays were performed to detect the expression and phosphorylation of IRS-1 and Akt, which are 2 critical proteins in the insulin signaling pathway. RESULTS Both urea stimulation and 5/6 nephrectomy induced glucose uptake disorder in skeletal muscle cells (P<0.01). Skeletal muscle IR was aggravated in the Ang II group (P<0.05) but alleviated in the valsartan group (P<0.01). Regardless of the experimental method (in vivo or in vitro), tyrosine phosphorylation of IRS-1 and Akt were significantly lower (P<0.01) and serine phosphorylation was significantly higher (P<0.01) in the model group than in the sham/control group. Compared to the model group, additional Ang II aggravated abnormal phosphorylation (P<0.05); conversely, additional valsartan alleviated abnormal phosphorylation to some extent (P<0.05). CONCLUSIONS There is skeletal muscle insulin resistance in the presence of CRF. This phenomenon can be aggravated by Ang II and partially relieved by valsartan. One of the mechanisms of IR in CRF patients may be associated with the critical proteins in the IRS-PI3k-Akt pathway by changing their phosphorylation levels.

Albuminuria and Endothelial Dysfunction in Patients with Non-Diabetic Chronic Kidney Disease.

BACKGROUND Albuminuria has been associated with cardiovascular events, but whether such an association can be explained by endothelial dysfunction is not fully understood. In this study, we examined the relationship between the urine albumin-to-creatinine ratio (UACR) and biomarkers of endothelial function in patients with chronic kidney disease (CKD). MATERIAL AND METHODS The cross-sectional associations of renal dysfunction and UACR with procoagulant and inflammatory factors were evaluated for 151 consecutive CKD (stage 3-5) patients. Subjects were grouped by UACR (≤300 mg/g or >300 mg/g) and estimated glomerular filtration rate (eGFR) (30≤ eGFR <60, 15≤ eGFR <30, or eGFR <15 ml/min per 1.73 m²). RESULTS A higher UACR level was associated with an increase in von Willebrand factor antigen (vWF: Ag) levels, vWF activity, factor VIII, interleukin-2, and log (interleukin-6), even after adjustment for risk factors. Linear regression analysis indicated that for every 88.5 mg/g increase in UACR, the vWF activity and factor VIII were elevated by 8.3% and 6.3%, respectively. The factorial design ANOVA data showed no statistically significant interaction between UACR and CKD stage with procoagulant and inflammatory factors. CONCLUSIONS Our study shows an eGFR-independent association of higher UACR with elevations in markers of endothelial dysfunction and inflammatory factors in CKD patients.

Decreased Serum C3 Levels in Immunoglobulin A (IgA) Nephropathy with Chronic Kidney Disease: A Propensity Score Matching Study.

BACKGROUND The effects of low serum C3 levels and the activation of the complement system on the development and the prognosis of IgAN are unclear. The present study aimed to determine whether decreased levels of complement C3 influence the prognosis of IgAN patients with chronic kidney disease. MATERIAL AND METHODS We enrolled a total of 1564 patients with primary IgAN diagnosed by renal biopsy at the Chinese PLA General Hospital from January 2011 to March 2015. The endpoint was end-stage renal disease (ESRD) or a doubling of the baseline serum creatinine (D-SCr) level. All patients were using 1: 1 propensity score matching (PSM), and the baseline values were not significantly different between these 2 groups (P>0.05). RESULTS During a follow-up period, 14 patients in the group with decreased C3 levels reached the endpoint, with 12 patients with normal C3 levels. There was no significant difference between the 2 groups in achieving D-SCr or ESRD (P=0.676). In multivariate Cox analysis, adjusted for demographic and laboratory examination, the risk of reaching the endpoint was comparable in the 2 groups (HR, 0.70; 95% CI, 0.27-1.78; P=0.449;). Furthermore, the risk of reaching ESRD (HR, 0.83; 95% CI, 0.25-2.75; P=0.757) and D-SCr (HR, 1.45; 95% CI, 0.20-10.60; P=0.718) did not differ between the 2 groups. CONCLUSIONS Decreased serum C3 levels in IgA nephropathy with chronic kidney disease did not play a decisive role in renal progression.

Hypercoagulable state evaluated by thromboelastography in patients with idiopathic membranous nephropathy.

The aims of this study were to evaluate the characteristics of hypercoagulable states in patients with membranous nephropathy (MN) via thromboelastography (TEG) and to identify risk factors. 235 MN patients who had undergone TEG examinations from 2011 to 2014 were included. An abnormality in at least two TEG parameters is considered a hypercoagulable state. Patient data was compared between the hypercoagulable and non-hypercoagulable groups. Potential risk factors for hypercoagulability were analyzed by logistic regression models. Subgroup analysis was performed in hypercoagulable patients. Compared to the non-hypercoagulable MN patients, the hypercoagulable patients showed a significantly higher proportion of female patients, urinary protein, platelet count, triglyceride and fibrinogen level, along with more severe hypoproteinemia and a reduction of serum antithrombin III. Correlation analysis showed that hypoproteinemia was the primary risk factor for hypercoagulability in MN patients. Among the hypercoagulable MN patients, a subgroup TEG parameter analysis showed that glucocorticoids-used subgroup and smoker subgroup had shortened time to initial fibrin formation (R value) and increased coagulation index respectively (P < 0.05), indicating a more serious hypercoagulable state. Meanwhile, the time to initial fibrin formation (R value) and time to clot formation (K value) of the statin-used patients were remarkably higher than those of the non-statin patients. TEG examinations facilitated the detection of hypercoagulable states in MN patients, and hypoproteinemia was the most important risk factor for hypercoagulability in these patients. The use of glucocorticoids and smoking may help to aggravate hypercoagulable states, while statin drugs may alleviate hypercoagulability.

Shenhua Tablet inhibits mesangial cell proliferation in rats with chronic anti-Thy-1 nephritis.

BACKGROUND: In China, mesangial proliferative glomerulonephritis (MsPGN) is one of the most common kidney diseases. In this study, we treated a rat model of chronic anti-Thy-1 MsPGN with Shenhua Tablet and evaluated whether the tablet was able to protect the kidney function. Thirty-six Wistar rats were randomly divided into six groups: (1) Sham surgery (Sham); (2) anti-Thy-1 nephritis model (Thy-1); (3) anti-Thy-1 nephritis model + irbesartan-treated (Irb); (4) anti-Thy-1 nephritis model + low-dose of Shenhua Tablet (SHL); (5) anti-Thy-1 nephritis model + medium-dose of Shenhua Tablet (SHM); (6) anti-Thy-1 nephritis model + high-dose of Shenhua Tablet (SHH). RESULTS: Thirteen weeks after drug treatment, urinary proteins were quantified and renal pathological changes were thoroughly examined at the time point of 24 h. Meanwhile, the expression levels of p-Erk1/2, cyclin D1 and p21 at the renal cortex were also tested. The levels of urinary proteins and total cholesterol in the blood were significantly reduced in rats treated with any drug tested in this study. The level of triglyceride was significantly reduced in all three Shenhua Tablet-treated groups. Renal pathomorphological scores were significantly improved in groups of Irb, SHM and SHH. Mesangial cell proliferation was significantly inhibited in any drug-treated group. p-Erk1/2 and cyclin D1 were downregulated whereas p21 was upregulated in the renal cortex. CONCLUSIONS: Our study indicated that Shenhua Tablet is able to inhibit the abnormal proliferation of mesangial cells and to prevent kidney damage, which is likely associated with downregulation of p-Erk1/2 and reduced activity of its downstream target-cyclin D1.

Therapeutic effect of double-filtration plasmapheresis combined with methylprednisolone to treat diffuse proliferative lupus nephritis.

OBJECTIVE: The efficacy of double-filtration plasmapheresis (DFPP), combined with methylprednisolone, to treat diffuse proliferative lupus nephritis (LN) was studied. METHODS: Twenty-four patients who were admitted to the hospital and diagnosed with diffuse proliferative LN (LN Class IV-G(A)) through renal biopsy from 2011 to 2013 were recruited as the study subjects. The patients' clinical manifestations were nephritic syndrome and/or renal insufficiency. The pathological features were glomerular diffuse proliferative lesions. The patients were divided into two groups: the treatment group and the control group, with 12 patients in each group. The patients in the treatment group were first treated with DFPP combined with methylprednisolone (0.8-1.0 mg/kg/day); subsequently, they were put on methylprednisolone therapy only. The patients in the control group were first put on methylprednisolone pulse therapy (500-1,000 mg) for 3 days; subsequently, they were treated with methylprednisolone (0.8-1.0 mg/kg/day) combined with mycophenolate mofetil (1.5 g/day). The patients were observed for 24 months. Levels of hemoglobin, platelet, albumin, serum creatinine, 24-h urinary protein, serum C3 , antinuclear antibody (ANA), anti-dsDNA, and anti-Smith were measured at 0, 3, 6, 12, and 24 months. Complete remission and recurrence standards were established. The total dosages of methylprednisolone were calculated. Repeated renal biopsy was performed on several patients. RESULTS: There was no statistical significance in the baseline conditions of the treatment and the control groups. For the treatment group, no plasmapheresis-related complications occurred. The two groups showed no significant difference in complete remission. The patients' edema and serous effusion resolved, urine volume, serum creatinine, and albumin levels returned to normal, urine protein decreased in treatment group more rapidly than the patients in the control group. The mean dose of methylprednisolone received in the treatment group was lower than in the control group. The complement C3 levels in the treatment group were significantly higher than in the control group. The recurrence rate in the treatment group was lower than in the control group. Repeated renal biopsies on several patients in the treatment group indicated that their pathology improved significantly, changing from LN (IV) to LN(II-III). CONCLUSIONS: Appropriate application of DFPP combined with glucocorticoid therapy could accelerate the remission of diffuse proliferative LN, reduce overall glucocorticoid dosage, prevent recurrence, and maintain C3 level in a higher level. J. Clin. Apheresis 31:375-380, 2016. © 2015 Wiley Periodicals, Inc.

Renal Protective Effect of Probucol in Rats with Contrast-Induced Nephropathy and its Underlying Mechanism.

BACKGROUND: Contrast-induced nephropathy (CIN) refers to acute renal damage that occurs after the use of contrast agents. This study investigated the renal protective effect of probucol in a rat model of contrast-induced nephropathy and the mechanism of its effect. MATERIAL AND METHODS: Twenty-eight Wistar rats were randomly divided into the control group, model group, N-acetylcysteine(NAC) group, and probucol group. We used a rat model of iopromide-induced CIN. One day prior to modeling, the rats received gavage. At 24 h after the modeling, blood biochemistry and urine protein were assessed. Malondialdehyde (MDA) and superoxide dismutase (SOD) were measured in renal tissue. Kidney sections were created for histopathological examination. RESULTS: The model group of rats showed significantly elevated levels of blood creatinine, urea nitrogen, 24-h urine protein, histopathological scores, and parameters of oxidative stress (P<0.05). Both the NAC and probucol groups demonstrated significantly lower Scr, BUN, and urine protein levels compared to the model group (P<0.05), with no significant difference between these 2 groups. The NAC group and the probucol group had significantly lower MDA and higher SOD than the model group at 24 h after modeling (P<0.05). The 8-OHdG-positive tubule of the probucol group and NAC group were significantly lower than those of the model group (p=0.046, P=0.0008), with significant difference between these 2 groups (P=0.024). CONCLUSIONS: Probucol can effectively reduce kidney damage caused by contrast agent. The underlying mechanism may be that probucol accelerates the recovery of renal function and renal pathology by reducing local renal oxidative stress.

Na+/H+ exchanger-1 reduces podocyte injury caused by endoplasmic reticulum stress via autophagy activation.

Podocyte injury has a critical role in the pathogenesis of proteinuria. Induction of endoplasmic reticulum (ER) stress is thought to lead to podocyte injury; however, no effective strategy for reducing ER stress-induced injury has been identified. We investigated specific mechanisms for reducing podocyte injury caused by ER stress. We found that the induction of ER stress in podocytes was related to cytoskeleton injury and increased proteinuria, which was associated with autophagy activation and downregulation of Na(+)/H(+) exchanger-1 (NHE-1) in the rat model of passive Heymann nephritis. Using mouse podocyte cells (MPCs), we showed that ER stress could lead to podocyte injury accompanied by autophagy activation, and the disturbance of autophagy aggravated cytoskeleton loss under conditions of ER stress. The balance between autophagy activation and ER stress was critical to podocyte survival, in which the efficiency of autophagy could have a pivotal role. Strikingly, the overexpression and small interfering RNA knockdown of NHE-1 results suggested that NHE-1 exerts a protective effect by reducing the loss of synaptopodin in MPCs exposed to ER stress. This protective mechanism involves NHE-1 activation of autophagy via the PI3K/Akt pathway to reduce ER stress injury in podocytes. This mechanism may provide a new pathway to prevent podocyte injury.

Applicability of chronic kidney disease epidemiology collaboration equations in a Chinese population.

BACKGROUND: Accurate estimated glomerular filtration rates (eGFR) is an important step in the diagnosis of chronic kidney disease (CKD). The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, based on creatinine alone (eGFRcr), was developed to improve on the Modification of Diet in Renal Disease equation, in particular by addressing the systematic underestimation of high GFR. Whether the CKD-EPI equation, based on cystatin C alone (eGFRcys), or the combined creatinine-cystatin C CKD-EPI equation (eGFRcr-cys C), actually perform better than the CKD-EPI equation based on creatinine (eGFRcr) remains unknown, especially in Asians including Chinese populations, where eGFR equations may overestimate true GFR. METHODS: A standard dual plasma sampling method (DPSM) of estimating (99m)Tc-diethylene triamine penta-acetic acid clearance was used to determine the reference or measured GFR (mGFR). Linear regression analysis, Bland-Altman analysis, bias, absolute bias and accuracy (P30) were used to compare the performance of the combined creatinine-cystatin C equation (eGFRcr-cys) and equations based on each marker alone (eGFRcr and eGFRcys) in Chinese subjects, including both patients with CKD and healthy individuals. RESULTS: We enrolled 617 Chinese participants (49.11% female, 47.11 ± 17.25 years old), with a mean mGFR of 73.80 ± 37.55 mL/min/1.73 m(2). The predictive abilities (r), the accuracy (P15, P30, P50), bias and absolute bias of the eGFRcr-cys equation were superior to eGFRcr equation and the eGFRcys equation in overall samples. Bland-Altman analysis also demonstrated a consistent result. When compared in subgroups, the accuracy (P30) of all three equations exceeded 90% at mGFR ≥90 mL/min/1.73m(2); the eGFRcr-cys equation had the highest accuracy (P30: 95.56%). At mGFR 60-89 mL/min/1.73 m(2), the accuracies (P30) of the eGFRcr-cys and eGFRcr equations exceeded the acceptable level (≥70%), and there was no significant difference between them (P = 0.58). At mGFR <60 mL/min/1.73 m(2), the accuracy (P30) of all three equations was below 70%, but the eGFRcr-cys equation had the greatest precision. CONCLUSIONS: The performances of the eGFRcr-cys and eGFRcr equations were similar to superior to that of the eGFRcys equation at higher GFR levels in an Asian population, especially in normal and mild to moderate kidney disease. Further improvement is needed for these equations at GFR <60 mL/min per 1.73 m(2).

Treatment of 5/6 nephrectomy rats with sulodexide: a novel therapy for chronic renal failure.

AIM: Sulodexide, a glycosaminoglycan, could reduce albuminuria in diabetic patients. The aim of this study was to determine whether sulodexide could be used to treat chronic kidney failure in rats. METHODS: Sixty Wistar rats undergone 5/6 nephrectomy, then were randomly divided into 4 groups: the model group, sulodexide group (sulodexide 5 mg/kg per day, im), irbesartan group irbesartan (20 mg/kg per day, ig) and sulodexide plus irbesartan group. Another 12 rats were enrolled into the sham operation group. After the treatments for 4, 8 and 12 weeks, urinary protein and serum creatinine levels were measured. After 12 weeks, serum cholesterin and triglycerides levels were measured, and the degrees of glomerular sclerosis and renal tubulointerstitial fibrosis were scored. The expression of aminopeptidase P (JG-12) in the renal tissue was examined using immunohistochemical staining. The renal expressions of endothelial nitric oxide synthase (eNOS) and tissue type plasminogen activator (tPA) were detected with RT-PCR and Western blot. RESULTS: Proteinuria was markedly attenuated in the sulodexide-treated groups. After 4 and 8 weeks only the sulodexide-treated groups showed significant reduction in serum creatinine; while after 12 weeks all the three treatment groups showed significant reduction in serum creatinine. Furthermore, all the three treatment groups showed significant reduction in the scores of glomerular sclerosis and tubulointerstitial fibrosis. The glomerular expression of JG-12 was increased in both the sulodexide group and the sulodexide plus irbesartan group, but not in the irbesartan group. The eNOS mRNA and protein expression was decreased and the tPA mRNA and protein expression was significantly increased in the model group compared with Sham group. Sulodexide, irbesartan, and their combination reversed the decrease of eNOS expression but increased the tPA expression much more compared with model group. CONCLUSION: Sulodexide was similar to irbesartan that can decrease proteinuria and attenuate renal lesions in 5/6 nephrectomy rats. The renal protection by sulodexide might be achieved via its impact on renal vascular endothelial cells.

Clinical and pathological analysis of hepatitis B virus-related membranous nephropathy and idiopathic membranous nephropathy.

OBJECTIVE: The Hepatitis B virus infection rate is high in the Chinese population. The implications of HBV infection are widely recognized, and membranous glomerulonephritis is the most common renal lesion associated with HBV infection. We compared the clinicopathologic features of 119 HBV-related membranous nephropathy (HBV-MN) and 143 idiopathic membranous nephropathy (IMN) patients to identify those factors that facilitate their discrimination. METHODS: Cohort analysis of demographic information, clinical manifestations, laboratory parameters, renal pathology and prognostic features of the two groups. RESULTS: Most HBV-MN patients were young or middle-aged; the onset age in the HBVMN group was younger than the IMN group (p < 0.05). A male predominance was found in both groups. And the two groups both presented with heavy proteinuria or nephrotic syndrome. In contrast to IMN patients, the HBV-MN group was presented with a high occurrence of microscopic hematuria (73.95 vs. 35.66%) and renal insufficiency (47.06 vs. 24.48%). Plasma complement C3 and C4 in HBV-MN patients were significantly lower than in IMN patients (p < 0.05). The hyperlipidemia was more severe in IMN patients (p < 0.05). The occurrences of segmental glomerular damage, mesangial cell proliferation and tubulointerstitial damage were more common in the HBV-MN group (p < 0.05). Immunofluorescence staining of polyclonal immunoglobulin and polytypic complement immunoglobulin were more frequent in the HBV-MN group. The followup data showed there were no statistic differences in the prognosis between HBV-MN and IMN. CONCLUSION: HBV-MN patients commonly showed nephrotic syndrome accompanied with renal and hepatic dysfunction which was different from IMN patients. The primary pathological feature of HBVMN was atypical membranous nephropathy, which is usually associated with the inflammatory changes in HBV infection. The renal survival rates did not differ between HBVMN patients and IMN patients.

Higher HOMA-IR index and correlated factors of insulin resistance in patients with IgA nephropathy.

OBJECTIVE: To investigate the index of homeostasis model of insulin resistance (HOMA-IR) in IgA nephropathy (IgAN) patients, and to explore the possible correlated factors contributing to insulin resistance (IR) within these patients. MATERIAL: There were 255 IgAN patients and 45 membranous nephropathy (MN) patients in our database. We identified 89 IgAN subjects and 21 MN subjects without diabetes and undergoing glucocorticoid therapy for at least 6 months. METHODS: Data regarding physical examination, blood chemistry and renal pathology were collected from 89 IgAN subjects and 21 MN subjects. Then 62 IgAN patients and 19 MN patients with chronic kidney disease (CKD) Stage 1 - 2 were selected for the comparison of HOMA-IR index, 89 IgAN patients were selected for multiple regression analysis to test for correlated factors of HOMA-IR index with IgAN patients. RESULTS: Comparison between IgAN and MN show that HOMA-IR index was significantly higher in IgAN patients with CKD Stage 1 - 2. After logarithmic transformation with urine protein (UPr), Ln(UPr) (b = 0.186, p = 0.008), eGFR (b = -0.005, p = 0.014), > 50% of glomeruli with mesangial hypercellularity (b = 0.285, p = 0.027) and body mass index (BMI) (b = 0.039, p = 0.008) were correlated factors of HOMA-IR index in the multiple regression analysis. CONCLUSION: IgAN patients had higher HOMA-IR index compared with MN in the stages of CKD 1 - 2. For IgAN patients, more UPr, lower eGFR, > 50% of glomeruli with mesangial hypercellularity and higher BMI were correlated with IR.

[Protective effects of compound shenhua tablet on diabetic nephropathy rats].

OBJECTIVE: To observe the renal protection effects of Compound Shenhua Tablet (CST) on diabetic nephropathy (DN) rats. METHODS: DN rats were given a normal diet for 9 months after they were induced by intraperitoneal injection of STZ at the dose of 65 mg/kg after uninephrectomized. They were randomly divided into 4 groups, i. e., the normal control group, the model control group, the CST group, and the Irbesartan group. The intervention was given by gastrogavage for 6 weeks. The general state, 24 h urine protein, urine micro-albumin (mAlb), serum creatinine (SCr), blood urea nitrogen (BUN), glucose (GLU), triglyceride (TG), total cholesterol (TC), total protein (TP), and albumin (ALB) levels were observed before and after intervention. Renal pathological changes were observed by PAS staining and transmission electron microscope. RESULTS: After 6 weeks of drug intervention, when compared with the model control group, the general state was improved in the CST group and the Irbesartan group. The levels of 24 h urine protein, urine mAlb, SCr, BUN, GLU, TG, and TC were obviously lower in the CST group and the Irbesartan group than in the model group as well as in the same group before treatment (P<0.05, P<0.01). There was no statistical difference between the two treatment groups (P>0.05). The renal pathological changes and the renal ultrastructure were improved to some degree in the two groups when compared with those in the model control group. CONCLUSIONS: CST could attenuate the renal damage of diabetes and delay renal deterioration process. Its effectiveness was equivalent to that of Irbesartan.

Luteolin can ameliorate renal interstitial fibrosis-induced renal anaemia through the SIRT1/FOXO3 pathway.

Luteolin is a natural flavonoid exhibiting multiple pharmacological activities. Renal anaemia is an important complication of chronic kidney disease (CKD). Whether luteolin can ameliorate renal interstitial fibrosis-induced renal anaemia remains unclear. We examined the therapeutic effects of luteolin in in vitro and in vivo models of renal interstitial fibrosis-induced renal anaemia. After high-throughput sequencing analysis of animal samples, we screened differentially expressed genes (DEGs) associated with luteolin-mediated improvements, performed GO and KEGG functional and pathway enrichment analyses, and validated the mechanism in vitro and in vivo. In vivo, haemoglobin and haematocrit were increased significantly, blood urea nitrogen and creatinine were decreased significantly, and the degree of renal interstitial injury and fibrosis was significantly alleviated in luteolin-treated mice compared with model mice. Erythropoietin (EPO) and hypoxia inducible factor 2A (HIF2A) levels were significantly increased and alpha smooth muscle actin (α-SMA), collagen I (COLI) and fibronectin (FN) levels were significantly decreased. Transcriptomic analysis revealed significant increases in sirtuin 1 (SIRT1) and forkhead box O3 (FOXO3) after luteolin intervention; these effects were validated in vitro and in vivo. Combined treatment with luteolin and the SIRT1 activator resveratrol or the SIRT1 inhibitor sirtinol and SIRT1-siRNA transfection revealed that blocking SIRT1 reduced FOXO3 expression and significantly decreased the benefits of luteolin, while resveratrol had the opposite effects. Molecular docking analysis indicated a stable conformation between luteolin and SIRT1. In vitro and in vivo systematic and transcriptomic studies showed that luteolin attenuates renal anaemia caused by renal fibrosis through the SIRT1/FOXO3 pathway.

NAD blocks high glucose induced mesangial hypertrophy via activation of the sirtuins-AMPK-mTOR pathway.

BACKGROUND/AIMS: Since the discovery of NAD-dependent deacetylases, Sirtuins, it has been recognized that maintaining intracellular levels of NAD is crucial for the management of stress-response of cells. Here we show that high glucose(HG)-induced mesangial hypertrophy is associated with loss of intracellular levels of NAD. This study was designed to investigate the effect of NAD on HG-induced mesangial hypertrophy. METHODS: The rat glomerular mesangial cells (MCs) were incubated in HG medium with or without NAD. Afterwards, NAD(+)/NADH ratio and enzyme activity of Sirtuins was determined. In addition, the expression analyses of AMPK-mTOR signaling were evaluated by Western blot analysis. RESULTS: We showed that HG induced the NAD(+)/NADH ratio and the levels of SIRT1 and SIRT3 activity decreased as well as mesangial hypertrophy, but NAD was capable of maintaining intracellular NAD(+)/NADH ratio and levels of SIRT1 and SIRT3 activity as well as of blocking the HG-induced mesangial hypertrophy in vitro. Activating Sirtuins by NAD blocked the activation of pro-hypertrophic Akt signaling, and augmented the activity of the antihypertrophic AMPK signaling in MCs, which prevented the subsequent induction of mTOR-mediated protein synthesis. By AMPK knockdown, we showed it upregulated phosphorylation of mTOR. In such, the NAD inhibited HG-induced mesangial hypertrophy whereas NAD lost its inhibitory effect in the presence of AMPK siRNA. CONCLUSION: These results reveal a novel role of NAD as an inhibitor of mesangial hypertrophic signaling, and suggest that prevention of NAD depletion may be critical in the treatment of mesangial hypertrophy.

Nomogram prediction model for renal anaemia in IgA nephropathy patients.

In this study, we focused on the influencing factors of renal anaemia in patients with IgA nephropathy and constructed a nomogram model. We divided 462 patients with IgA nephropathy diagnosed by renal biopsy into anaemic and non-anaemic groups. Then, the influencing factors of renal anaemia in patients with IgA nephropathy were analysed by least absolute shrinkage and selection operator (LASSO) regression and multivariable logistic regression, and a nomogram model for predicting renal anaemia was established. Eventually, nine variables were obtained, which are easy to apply clinically. The areas under the receiver operating characteristic (ROC) curve and precision-recall (PR) curve reached 0.835 and 0.676, respectively, and the C-index reached 0.848. The calibration plot showed that the model had good discrimination, accuracy, and diagnostic efficacy. In addition, the C-index of the model following internal validation reached 0.823. Decision curve analysis suggested that the model had a certain degree of clinical significance. This new nomogram model of renal anaemia combines the basic information, laboratory findings, and renal biopsy results of patients with IgA nephropathy, providing important guidance for predicting and clinically intervening in renal anaemia.

Grape seed extract enhances eNOS expression and NO production through regulating calcium-mediated AKT phosphorylation in H2O2-treated endothelium.

GSE (grape seed extract) has been shown to exhibit protective effects against cardiovascular events and atherosclerosis, although the underlying molecular mechanisms of action are unknown. Herein, we assessed the ability of GSE to enhance eNOS (endothelial nitric oxide synthase) expression and NO (nitric oxide) production in H2O2 (hydrogen peroxide)-treated HUVECs (human umbilical vein endothelial cells). GSE enhanced eNOS expression and NO release in H2O2-treated cells in a dose-dependent manner. GSE inhibited intracellular ROS (reactive oxygen species) and reduced intracellular calcium in a dose-dependent manner in H2O2-treated cells, as shown by confocal microscopy. ROS was inhibited in cells pretreated with 5.0 microM GSE, 2.0 microM TG (thapsigargin) and 20.0 microM 2-APB (2-aminoethoxydiphenyl borate) instead of 0.25 microM extracellular calcium. In addition, GSE enhanced eNOS expression and reduced ROS production via increasing p-AKT (AKT phosphorylation) with high extracellular calcium (13 mM). In conclusion, GSE protected against endothelial injury by up-regulation of eNOS and NO expression via inhibiting InsP3Rs (inositol 1,4,5-trisphosphate receptors)-mediated intracellular excessive calcium release and by activating p-AKT in endothelial cells.

Influences of renal anemia on the pathology of IgA nephropathy: a study based on propensity score matching.

OBJECTIVE: This study aims to investigate the influences of renal anemia on the pathogenesis of IgA nephropathy using propensity score matching (PSM). METHODS: Renal biopsies from 462 patients with IgA nephropathy were enrolled in this study. PSM was used to balance intergroup covariates, and matching results were verified using a dot-plot of standardized mean differences and histograms of the propensity score distribution and distance distribution. The matched data were used to analyze the impact of renal anemia on the pathological indicators of IgA nephropathy by logistic regression. RESULTS: A total of 132 pairs of patients from the renal anemia group and the non-renal anemia group were matched by PSM; after matching, the standard deviations of 13 covariates were within 0.25. Multivariate logistic regression results suggested that the CKD4-5 stage of IgA nephropathy and tubular atrophy/interstitial fibrosis >50% were independent risk factors for renal anemia. CONCLUSIONS: Via PSM, we demonstrated that decreased eGFR and severe tubular atrophy/interstitial fibrosis are correlated with renal anemia in IgA nephropathy. In clinical practice, renal anemia in patients with IgA nephropathy of CKD3 stage or above should be closely monitored and managed.

Clinical and pathological factors of renal anaemia in patients with IgA nephropathy in Chinese adults: a cross-sectional study.

OBJECTIVE: Few studies with large sample populations concerning renal anaemia and IgA nephropathy have been reported worldwide. The purpose of this cross-sectional study was to examine the clinical and pathological characteristics and influencing factors associated with renal anaemia in patients with IgA nephropathy, which is the most common aetiology of chronic kidney disease. METHODS: A total of 462 hospitalised patients with IgA nephropathy confirmed by renal biopsy who met the inclusion criteria were consecutively recruited from January 2014 to January 2016. Their general information, routine blood test results, blood chemistries, estimated glomerular filtration rates (eGFRs) and renal pathologies were collected. The Oxford classification was used to characterise the renal pathologies. Univariable and multivariate logistic regression models were used to analyse the influencing factors of anaemia associated with IgA nephropathy. RESULTS: The incidence of renal anaemia was 28.5% (132/462 patients) in our study (21.3% in males and 38.9% in females). The anaemia type was primarily normocytic and normochromic. The rate of anaemia in patients with eGFR values of 30-59 mL/min/1.73 m2 was higher than that in patients with an eGFR >60 mL/min/1.73 m2 (42.9% vs 17.8%, p<0.001). Notably, in the group with eGFR values <15 mL/min/1.73 m2, the anaemia rate was 100%. Logistic regression analysis showed that factors affecting anaemia in patients with IgA nephropathy included being female (OR 3.02, 95% CI 1.76 to 5.17), low albumin levels (OR 0.87, 95% CI 0.82 to 0.93), reduced eGFR values (OR 0.98, 95% CI 0.97 to 0.99) and renal tubulointerstitial lesions >50% (OR 2.57, 95% CI 1.22 to 5.40). CONCLUSIONS: The female sex, hypoalbuminaemia, reduced eGFR levels and severe renal tubulointerstitial lesions were correlated with renal anaemia in patients with IgA nephropathy. These results provide new insight into our understanding of anaemia in IgA nephropathy and may improve the management and treatment of clinical renal anaemia.