Research progress in the application of proteomics technology in brain injury.

The aim of this article is to review the application progress of proteomics technology in brain injury research in recent years, point out the current problems that need to be overcome, and explore the application prospects of proteomics analysis in brain injury. This study also aims to retrieve all literature on brain injury and proteomics and summarize it. Through searching and screening, the widespread application of proteomics technology in the treatment of traumatic brain injury (TBI) and the use of a large number of TBI biomarkers were discovered. The pathways mediated by some biomarkers and the physiological and pathological mechanisms of occurrence were elucidated. The current classification of brain injury is mainly based on subjective evaluation of clinical symptoms, combined with objective imaging. However, its practical value is often limited when applied to prognosis evaluation in brain injury. Proteomics technology can make up for this deficiency and provide a reference for the prevention and treatment of brain injury.

Dysfunctional Coupling of Cerebral Blood Flow and Susceptibility Value in the Bilateral Hippocampus is Associated with Cognitive Decline in Nondialysis Patients with CKD.

SIGNIFICANCE STATEMENT: Patients with end stage CKD often develop cognitive decline, but whether this is related to the underlying disease or to hemodialysis remains unclear. We performed three-dimensional pseudocontinuous arterial spin labeling and quantitative susceptibility mapping prospectively in 40 patients with stage 1-4 CKD, 47 nondialysis patients with stage 5 CKD, and 44 healthy controls. Our magnetic resonance imaging data demonstrate that changes in cerebral blood flow-susceptibility coupling might underlie this cognitive decline, perhaps in the hippocampus and thalamus. These results suggest that magnetic resonance imaging parameters are potential biomarkers of cognitive decline in patients with CKD. Moreover, our findings may lead to discovery of novel therapeutic targets to prevent cognitive decline in patients with CKD. BACKGROUND: Cerebral blood flow (CBF) and susceptibility values reflect vascular and iron metabolism, providing mechanistic insights into conditions of health and disease. Nondialysis patients with CKD show a cognitive decline, but the pathophysiological mechanisms underlying this remain unclear. METHODS: Three-dimensional pseudocontinuous arterial spin labeling and quantitative susceptibility mapping were prospectively performed in 40 patients with stage 1-4 CKD (CKD 1-4), 47 nondialysis patients with stage 5 CKD (CKD 5ND), and 44 healthy controls (HCs). Voxel-based global and regional analyses of CBF, susceptibility values, and vascular-susceptibility coupling were performed. Furthermore, the association between clinical performance and cerebral perfusion and iron deposition was analyzed. RESULTS: For CBF, patients with CKD 5ND had higher normalized CBF in the hippocampus and thalamus than HCs. Patients with CKD 5ND had higher normalized CBF in the hippocampus and thalamus than those with CKD 1-4. The susceptibility values in the hippocampus and thalamus were lower in patients with CKD 5ND than in HCs. Patients with CKD 5ND had higher susceptibility value in the caudate nucleus than those with CKD 1-4. More importantly, patients with CKD 5ND had lower CBF-susceptibility coupling than HCs. In addition, CBF and susceptibility values were significantly associated with clinical performance. CONCLUSIONS: Our findings demonstrate a new neuropathological mechanism in patients with CKD, which leads to regional changes in CBF-susceptibility coupling. These changes are related to cognitive decline, providing potential imaging markers for assessing clinical disability and cognitive decline in these patients.

Association of plasma microRNA-16-5p and abdominal aortic calcification in maintenance hemodialysis patients.

Recent studies have shown that microRNA-16-5p (miR-16-5p) plays a crucial role in the pathological mechanism of vascular calcification. Nevertheless, the expression profile of miR-16-5p in maintenance hemodialysis (MHD) patients who are predisposed to vascular calcification remains unknown. This study aims to investigate the potential associations between calcification risk and serum miR-16-5p expression among MHD patients. This cross-sectional study involved 132 MHD patients from the Dialysis Center of Beijing Friendship Hospital between 1 January 2019 and 31 December 2020. The degree of calcification in MHD patients was assessed using the Abdominal aortic calcification (AAC) score, and miR-16-5p expression was quantified using quantitative real-time polymerase chain reaction (qRT-PCR) with the 2-ΔΔCT method. Statistical analyses, including spearman correlation, linear regression and logistic regression analysis were used to explore the associations between laboratory parameters and AAC score. Calcifications were observed in 79(59.80%) patients. The linear regression showed a one-quartile decrease in miR-16-5p expression led to a significant increase in the AAC score by 5.336 (95% CI: 2.670-10.662, p = 0.000). Multivariate logistic regression analyses revealed that decreased miR-16-5p expression, reduced serum urea nitrogen, elevated white blood cell count, and longer dialysis vintage were significantly associated with an increased incidence of vascular calcification. The Area Under the Curve (AUC) of the Receiver Operating Characteristic (ROC) of the miR-16-5p-based logistic regression model was 0.842 (95% CI: 0.771-0.913, p = 0.000). There was an independent association between miR-16-5p expression and calcification degree. Lower miR-16-5p expression levels seem to be a potential risk factor of vascular calcification in MHD patients.

Construction of a miR-15a-based risk prediction model for vascular calcification detection in patients undergoing hemodialysis.

Vascular calcification (VC) is highly prevalent in patients undergoing hemodialysis, and is a significant contributor to the mortality rate. Therefore, biomarkers that can accurately predict the onset of VC are urgently required. Our study aimed to investigate serum miR-15a levels in relation to VC and to develop a predictive model for VC in patients undergoing hemodialysis at the Beijing Friendship Hospital hemodialysis center between 1 January 2019 and 31 December 2020. The patients were categorized into two groups: VC and non-VC. Logistic regression (LR) models were used to examine the risk factors associated with VC. Additionally, we developed an miR-15a-based nomogram based on the results of the multivariate LR analysis. A total of 138 patients under hemodialysis were investigated (age: 58.41 ± 13.22 years; 54 males). VC occurred in 79 (57.2%) patients. Multivariate LR analysis indicated that serum miR-15a, age, and WBC count were independent risk factors for VC. A miR-15a-based nomogram was developed by incorporating the following five predictors: age, dialysis vintage, predialysis nitrogen, WBC count, and miR-15a. The receiver operating characteristic (ROC) curve had an area under the curve of 0.921, diagnostic threshold of 0.396, sensitivity of 0.722, and specificity of 0.932, indicating that this model had good discrimination. This study concluded that serum miR-15a levels, age, and white blood cell (WBC) count are independent risk factors for VC. A nomogram constructed by integrating these risk factors can be used to predict the risk of VC in patients undergoing hemodialysis.

Multitarget therapy with a corticosteroid, cyclosporine and mycophenolate mofetil for idiopathic membranous nephropathy: a prospective randomized controlled trial.

BACKGROUND: The effectiveness of multitarget combination therapy with a corticosteroid, cyclosporine and mycophenolate mofetil for idiopathic membranous nephropathy (IMN) is unclear. In the present study, we aimed to compare the efficacy and safety of multitarget therapy with a cyclical corticosteroid-cyclophosphamide regimen in patients with IMN. METHODS: This was a single-centre, prospective, randomized, controlled trial. We randomly assigned patients with IMN to receive multitarget therapy (a combination of prednisone, cyclosporine and mycophenolate mofetil) or 6-month cyclical treatment with a corticosteroid and cyclophosphamide. The study patients were followed up for 12 months. The primary outcome was a composite of complete or partial remissions at 12 months. Adverse events were also assessed. RESULTS: The study cohort comprised 78 patients, 39 of whom received multitarget therapy and the other 39 cyclical alternating treatment with a corticosteroid and cyclophosphamide. At 12 months, 31 of 39 patients (79%) in the multitarget therapy group and 34 of 39 (87%) in the corticosteroid-cyclophosphamide group had achieved complete or partial remissions (relative risk 0.93; 95% confidence interval 0.72-1.21; P = .85; log-rank test). The prevalence of adverse events was significantly lower in the multitarget therapy group than in the corticosteroid-cyclophosphamide group [46% (18 of 39) vs 74% (29 of 39); P < .05]. CONCLUSIONS: Multitarget therapy for IMN patients is noninferior to cyclical alternating treatment with corticosteroid and cyclophosphamide in inducing proteinuria remission and has a better safety profile than the corticosteroid-cyclophosphamide combination.

Renalase Prevents Renal Fibrosis by Inhibiting Endoplasmic Reticulum Stress and Down-Regulating GSK-3ß/Snail Signaling.

Background: Treating renal fibrosis is crucial to delaying chronic kidney disease. The glycogen synthase kinase-3ß (GSK-3ß)/Snail pathway regulates renal fibrosis and Renalase can ameliorate renal interstitial fibrosis. However, it is not clear whether GSK-3ß/Snail signaling affects Renalase action. Here, we explored the role and mechanism of GSK-3ß/Snail in the anti-fibrosis action of Renalase. Materials and methods: We used mice with complete unilateral ureteral obstruction (UUO) and human proximal renal tubular epithelial (HK-2) cells with transforming growth factor-ß1 (TGF-ß1)-induced fibrosis to explore the role and regulatory mechanism of the GSK-3ß/Snail pathway in the amelioration of renal fibrosis by Renalase. Results: In UUO mice and TGF-ß1-induced fibrotic HK-2 cells, the expression of p-GSK-3ß-Tyr216/p-GSK-3ß-Ser9, GSK-3ß and Snail was significantly increased, and endoplasmic reticulum (ER) stress was activated. After Renalase supplementation, fibrosis was alleviated, ER stress was inhibited and p-GSK-3ß-Tyr216/p-GSK-3ß-Ser9, GSK-3ß and Snail were significantly down-regulated. The amelioration of renal fibrosis by Renalase and its inhibitory effect on GSK-3ß/Snail were reversed by an ER stress agonist. Furthermore, when an adeno-associated virus or plasmid was used to overexpress GSK-3ß, the effect of Renalase on delaying renal fibrosis was counteracted, although ER stress markers did not change. Conclusion: Renalase prevents renal fibrosis by down-regulating GSK-3ß/Snail signaling through inhibition of ER stress. Exogenous Renalase may be an effective method of slowing or stopping chronic kidney disease progression.

Effect of dialytic phosphate reduction rate on mortality in maintenance hemodialysis patients: a matched case-control study.

BACKGROUND: Phosphates, similar to urea, are small molecular substances that can be cleared during dialysis. Dialytic phosphate reduction rate (PRR) may, to some extent, be related to the relative amount of phosphates cleared during dialysis. However, few studies have evaluated the associations between PRR and mortality in maintenance hemodialysis (MHD) patients. In this study, we investigated the association between PRR and clinical outcomes in MHD patients. METHODS: This was a retrospective, matched case-control study. Data were collected from the Beijing Hemodialysis Quality Control and Improvement Center. Patients were divided into four groups according to PRR quartile. Age, sex, and diabetes were matched between the groups. The primary outcome was all-cause death, and the secondary outcome was cardiocerebrovascular death. RESULTS: The study cohort comprised 4063 patients who were divided into four groups according to the PRR quartile: group PRR1 (< 48.35%), group PRR2 (48.35% - 54.14%), group PRR3 (54.14% - 59.14%), and group PRR4 (≥ 59.14%). We enrolled 2172 patients (543 in each study group) by case-control matching. The all-cause death rates were as follows: group PRR1: 22.5% (122/543), group PRR2: 20.1% (109/543), group PRR3: 19.3% (105/543), and group PRR4: 19.3% (105/543). No significant differences in all-cause and cardiocerebrovascular death rates according to the Kaplan-Meier survival curves were found between the groups (log-rank test, P > 0.05). Multivariable Cox regression analysis revealed no significant differences in all-cause and cardiocerebrovascular death rates between the four groups (P = 0.461; adjusted hazard ratio, 0.99; 95% confidence interval, 0.97 - 1.02 versus P = 0.068; adjusted hazard ratio, 0.99; 95% confidence interval, 0.97 - 1.00, respectively). CONCLUSIONS: Dialytic PRR was not significantly associated with all-cause death and cardiocerebrovascular death in MHD patients.

Exosomes from high glucose-treated macrophages promote epithelial-mesenchymal transition of renal tubular epithelial cells via long non-coding RNAs.

BACKGROUND: Macrophages contribute to epithelial-mesenchymal transition (EMT) in diabetic nephropathy (DN). Exosomal long non-coding RNAs (lncRNAs) derived from macrophages play a major role in transmitting biological information, whereas related studies on DN are rare. Here we investigated the effects of exosomal lncRNAs from high glucose-treated macrophages on EMT. METHODS: High glucose-treated macrophage exosomes (HG-exos) were extracted by coprecipitation and stabilized. Then, mouse renal tubular epithelial cells were treated with HG-exos for 24 h. Expression of E-cadherin, α-smooth muscle actin (α-SMA), and fibronectin was detected by western blotting, qPCR, and immunofluorescence. High-throughput sequencing was then applied to analyze the bioinformatics of HG-exos. RESULTS: HG-exos inhibited the proliferation of tubular epithelial cells. Additionally, HG-exos markedly upregulated α-SMA and fibronectin expression and downregulated E-cadherin expression in tubular epithelial cells, indicating EMT induction. A total of 378 differentially expressed lncRNAs and 674 differentially expressed mRNAs were identified by high-throughput sequencing of HG-exos. Bioinformatics analysis and subsequent qPCR validation suggested 27 lncRNAs were enriched in the EMT-related MAPK pathway. Among them, ENSMUST00000181751.1, XR_001778608.1, and XR_880236.2 showed high homology with humans. CONCLUSION: Exosomes from macrophages induce EMT in DN and lncRNAs in exosomes enriched in the MAPK signaling pathway may be the possible mechanism.

Epidemiological analysis of death among patients on maintenance hemodialysis: results from the beijing blood purification quality Control and Improvement Center.

BACKGROUND: China has the largest number of patients on maintenance hemodialysis (MHD) worldwide. Despite continuous improvements in hemodialysis techniques, patients on MHD have a higher mortality rate than the general population. Understanding the characteristics of death in this population can better promote clinical practice, thereby improving patients' survival. METHODS: We collected demographic and clinical data for patients on MHD registered in the Beijing Blood Purification Quality Control and Improvement Center database from 2014 to 2020. The annual mortality rate was calculatedand the primary cause of end-stage renal disease (ESRD), dialysis vintage, and cause of death among deceased patients were analyzed. RESULTS: (1) 24,363 patients on MHD were included, of which 6,065 patients died from 2014 to 2020. The annual mortality rate fluctuated between 7.4% and 8.0%. The median age of death was 70.0 (60.8-79.0) years and the male to female ratio was 1.27:1 (2). The top three primary causes of ESRD in deceased patients were chronic glomerulonephritis (CGN), diabetic nephropathy (DN), and hypertensive nephropathy (HN). Comparison of the annual mortality rate showed DN > HN > CGN (3). The median dialysis vintage of deceased patients was 3.7 (1.8-6.9) years, which slowly increased annually. Patients with diabetes had a shorter dialysis vintage than patients without diabetes (3.4 vs. 4.1 years, Z = 8.3, P < 0.001) (4). The major causes of death were cardiovascular disease (20.2%), sudden death (18.1%), infection (17.9%), and cerebrovascular disease (12.6%). Proportions of death from cardiovascular disease, infection, and sudden death were higher in patients with diabetes (22.2%, 20.2%, and 20.0%) than patients without diabetes (18.4%, 15.8%, and 16.3%). Sudden death was the leading cause of death in young (18-44 years; 27.0%) and middle aged (45-64 years; 20.8%) patients, whereas infection was the leading cause of death in patients aged ≥ 75 years (24.5%). CONCLUSION: The annual mortality rate of patients on MHD in Beijing was relatively stable from 2014 to 2020. Sudden death was more likely to occur in young and middle-aged patients, and more patients aged ≥ 75 years died from infections.

Title: Bioinformatic Identification of Genes Involved in Diabetic Nephropathy Fibrosis and their Clinical Relevance.

Tubulointerstitial fibrosis is an important pathological feature of diabetic nephropathy that is associated with impaired renal function. However, the mechanism by which fibrosis occurs in diabetic nephropathy is unclear. Differentially expressed genes were identified from transcriptome profiles of renal tissue from diabetic patients and unilateral ureteral obstruction mice and intersected to obtain genes that may be involved in diabetic fibrosis. Biological function analysis and protein-protein interaction network analysis were performed. ROC curve and Pearson correlation analysis between hub genes were performed and glomerular filtration rate estimated. Finally, the RNA levels of hub genes were measured using real-time PCR. A total of 283 genes were identified as potentially involved in diabetic nephropathy fibrosis. TYROBP, CTSS, LCP2, LUM and TLR7 were identified as aberrantly expressed hub genes. Immune cell infiltration analysis demonstrated higher numbers of cytotoxic lymphocytes, B lineage cells, monocyte lineage cells, myeloid dendritic cells, neutrophils, and fibroblasts in the diabetic nephropathy group. The areas under ROC curves for TYROBP, CTSS, LCP2, LUM and TLR7 were 0.9167, 0.9583, 0.9917, 0.93333, and 0.9583, respectively (P < 0.001), and their correlation coefficients with estimated glomerular filtration rate were - 0.8332, - 0.752, - 0.7875, - 0.7567, and - 0.7136, respectively (P < 0.001). The RNA levels of TYROBP, CTSS, LUM and TLR7 were upregulated in high-glucose-treated human renal tubular epithelial cells (P < 0.005). Our study identified TYROBP, CTSS, LCP2, LUM and TLR7 as potentially involved in diabetic nephropathy fibrosis. Furthermore, TYROBP, CTSS, LUM and TLR7 may be associated with epithelial-mesenchymal transition of tubular epithelial cells.

Bioinformatics analysis of potential key ferroptosis-related genes involved in tubulointerstitial injury in patients with diabetic nephropathy.

Diabetic nephropathy (DN) is the primary complication of diabetes mellitus. Ferroptosis is a form of cell death that plays an important role in DN tubulointerstitial injury, but the specific molecular mechanism remains unclear. Here, we downloaded the DN tubulointerstitial datasets GSE104954 and GSE30529 from the Gene Expression Omnibus database. We examined the differentially expressed genes (DEGs) between DN patients and healthy controls, and 36 ferroptosis-related DEGs were selected. Pathway-enrichment analyses showed that many of these genes are involved in metabolic pathways, phosphoinositide 3-kinase/Akt signaling, and hypoxia-inducible factor-1 signaling. Ten of the 36 ferroptosis-related DEGs (CD44, PTEN, CDKN1A, DPP4, DUSP1, CYBB, DDIT3, ALOX5, VEGFA, and NCF2) were identified as key genes. Expression patterns for six of these (CD44, PTEN, DDIT3, ALOX5, VEGFA, and NCF2) were validated in the GSE30529 dataset. Nephroseq data indicated that the mRNA expression levels of CD44, PTEN, ALOX5, and NCF2 were negatively correlated with the glomerular filtration rate (GFR), while VEGFA and DDIT3 mRNA expression levels were positively correlated with GFR. Immune infiltration analysis demonstrated altered immunity in DN patients. Real-time quantitative PCR (qPCR) analysis showed that ALOX5, PTEN, and NCF2 mRNA levels were significantly upregulated in high-glucose-treated human proximal tubular (HK-2) cells, while DDIT3 and VEGFA mRNA levels were significantly downregulated. Immunohistochemistry analysis of human renal biopsies showed positive staining for ALOX5 and NCF2 protein in DN samples but not the controls. These key genes may be involved in the molecular mechanisms underlying ferroptosis in patients with DN, potentially through specific metabolic pathways and immune/inflammatory mechanisms.

Exosomes derived from bone marrow mesenchymal stem cells inhibit human aortic vascular smooth muscle cells calcification via the miR-15a/15b/16/NFATc3/OCN axis.

Cardiovascular events among patients with chronic kidney disease (CKD) are associated with vascular calcification (VC). Nevertheless, the process of vascular calcification is complicated. A mechanism of VC is cellular osteogenic transdifferentiation. The mechanism through which bone marrow mesenchymal stem cell-derived exosomes (BMSC-Exo) relieve VC is unknown. For the purpose of this study, we used human aortic vascular smooth muscle cells (HA-VSMCs) stimulated by high phosphate to investigate how BMSC-Exo works. Cell calcification was detected by Alizarin red S staining, AKP activity analysis, and the Ca2+ concentration test. The dual-luciferase reporter gene assays were utilized to confirm the targeting link between miR-15a-5p, miR-15b-5p, and miR-16-5p (miR-15a/15b/16) and nuclear factors of activated T cells 3 (NFATc3). The expression of osteogenic transdifferentiation biomarkers was detected using Western blot and RT-qPCR. Based on our findings, miR-15a/15b/16 plays a crucial role in BMSC-Exo's inhibitory effects on calcification and osteogenic transdifferentiation. We then confirmed that miR-15a/15b/16 specifically target the 3'UTR of NFATc3 mRNA and that three miRNAs are more effective than one miRNA. Moreover, we found that down-regulation of NFATc3 could inhibit osteocalcin (OCN) expression, thereby inhibiting the osteogenic transdifferentiation and calcification of HA-VSMCs. This study found that BMSC-Exo plays a role in calcification inhibition by transferring miR-15a/15b/16 and inhibiting their common target gene NFATc3, which down-regulates OCN expression and thus inhibits HA-VSMC osteogenic transdifferentiation. This study identifies a novel target for therapeutic therapy of CKD-VC.

Serum proteomics unveil characteristic protein diagnostic biomarkers and signaling pathways in patients with esophageal squamous cell carcinoma.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a common digestive tract malignant tumor with high incidence and dismal prognosis worldwide. However, the reliable biomarkers for clinical diagnosis and the underlying signaling pathways insights of ESCC are not unequivocally understood yet. The serum proteome may provide valuable clues for the early diagnosis of ESCC and the discovery of novel molecular insights. METHODS: In the current study, an optimized proteomics approach was employed to discover novel serum-based biomarkers for ESCC, and unveil abnormal signal pathways. Gene ontology (GO) enrichment analysis was done by Gene Set Enrichment Analysis (GSEA) and Metascape database, respectively. Pathway analysis was accomplished by GeneCards database. The correlation coefficient was assessed using Pearson and distance correlation analyses. Prioritized candidates were further verified in two independent validation sets by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC) staining. RESULTS: A total of 633 non-redundant proteins were identified in the serum of patients with ESCC, of which 59 and 10 proteins displayed a more than 1.5-fold increase or decrease compared with healthy controls. Verification was performed for six candidate biomarkers, including S100A8/A9, SAA1, ENO1, TPI1 and PGAM1. Receiver operating characteristics (ROC) curve plotting showed the high diagnostic sensitivity and specificity of these six protein molecules as a biomarker panel: the area under characteristic curve (AUC) is up to 0.945. Differentially expressed proteins were subjected to functional enrichment analysis, which revealed the dysregulation of signaling pathways mainly involved in glycolysis, TLR4, HIF-1α, Cori cycle, TCA cycle, folate metabolism, and platelet degranulation. The latter finding was all the more noteworthy as a strong positive correlation was discovered between activated glycolysis and TLR4 pathways and unfavorable clinicopathological TNM stages in ESCC. CONCLUSIONS: Our findings propose a potential serum biomarker panel for the early detection and diagnosis of ESCC, which could potentially broaden insights into the characteristics of ESCC from the proteomic perspective.

Association of abdominal aortic calcification with longitudinal changes in left ventricular mass of patients on hemodialysis and its prognostic value.

Vascular calcification (VC) and myocardial hypertrophy are very common in patients on hemodialysis (HD). Previous studies have only assessed the cross-sectional associations of VC with left ventricular mass (LVM) and the predictive value of individual factors. The present study investigated the relationship between abdominal aortic calcification (AAC) and LVM increment over time, and the combined effect of these factors on the outcomes of HD patients. 104 HD patients were enrolled. AAC scores were evaluated on left lateral lumbar spine radiographs. Echocardiography was performed to calculate the LVM changes during a 2-year period. At baseline, 91 patients (87.5%) had varying degrees of AAC (median score 6.0, range 2.0 - 11.0). After 2 years, the mean LVM change was 7.49 g (range -5.03 - 26.00 g), and 68 patients (65%) had an increased LVM. Patients with higher baseline AAC scores had significantly larger LVM and LVM index increments. Patients with increased LVM had significantly higher baseline AAC scores and hemoglobin, serum phosphate, and hypersensitive C-reactive protein levels. Multiple stepwise linear regression demonstrated that the baseline AAC was the only independent predictor of increased LVM after 2 years. 28 patients (26.9%) died in the subsequent 5 years. Patients with lower baseline AAC scores had a significantly higher cumulative survival rate than those with higher AAC scores. However, the LVM change (either alone or in combination with the AAC score) had no significant effect on survival. In conclusion, AAC is an independent predictor of LVM increase over time in HD patients. Prevention and treatment of VC may be a promising intervention target to improve left ventricular remodeling and outcomes in HD patients.

Randomized Control Study on Hemoperfusion Combined with Hemodialysis versus Standard Hemodialysis: Effects on Middle-Molecular-Weight Toxins and Uremic Pruritus.

INTRODUCTION: Classic hemodialysis schedules present inadequate middle-molecular-weight toxin clearance due to limitations of membrane-based separation processes. Accumulation of uremic retention solutes may result in specific symptoms (e.g., pruritus) and may affect clinical outcome and patient's quality of life. Hemoperfusion (HP) is a blood purification modality based on adsorption that can overcome such limitations, and thus, it may be interesting to test the efficacy of at least one session per week of HP combined with hemodialysis. This is a randomized, open-label trial, controlled, multicenter clinical study to investigate the effect of long-term HP combined with hemodialysis on middle-molecular-weight toxins and uremic pruritus in maintenance hemodialysis (MHD) patients. METHODS: 438 MHD patients from 37 HD centers in China with end-stage kidney disease (63.9% males, mean age 51 years) suffering from chronic intractable pruritus were enrolled in the study. Eligible patients were randomized into four groups: low-flux hemodialysis (LFHD), high-flux hemodialysis (HFHD), HP + LFHD, and HP + HFHD at a 1:1:1:1 ratio. Beta-2 microglobulin (ß2M) and parathyroid hormone (PTH) were measured at baseline, 3-6, and 12 months. At the same time points, the pruritus score was evaluated. The primary outcome was the reduction of ß2M and PTH, while the secondary outcome was the reduction of the pruritus score. RESULTS: In the two groups HP + LFHD and HP + HFHD, there was a significant decrease of ß2M and PTH levels after 12 months compared to the control groups. No significant differences were noted between HP + LFHD and HP + HFHD. Pruritus score reduction was 63% in the HP + LFHD group and 51% in the HP + HFHD group, respectively. CONCLUSION: The long-term HP + HD can reduce ß2M and PTH levels and improve pruritus in MHD patients independently on the use of high- or low-flux dialyzers, showing that the results are linked to the effect of adsorption.

Endoplasmic reticulum stress mediates parathyroid hormone-induced apoptosis in vascular smooth muscle cells.

Vascular calcification is one of the most common complications of chronic kidney disease (CKD), which is closely associated with increased mortality and morbidity rates of CKD patients. It has been reported that increased parathyroid hormone (PTH) aggravates vascular calcification in CKD patients. However, the direct role of PTH in vascular smooth muscle cells (VSMCs) is less elucidated. Here, we present evidence that PTH promotes apoptosis of VSMCs and endoplasmic reticulum (ER) stress participates in this process. Human aorta vascular smooth muscle cells (HASMCs) were treated with different concentrations of PTH for various time. HASMC apoptosis was detected by flow cytometry. Expression of phosphorylated (p)-PERK, CHOP, IRE1, p-JNK, and cleaved caspase 3 was determined by Western blotting. We found that PTH induced HASMC apoptosis and increased the expression of cleaved caspase 3. Furthermore, PTH activated PERK-CHOP and IRE1-JNK ER stress pathways. Either inhibition of JNK by SP600125 or CHOP by siRNA ameliorated PTH-induced apoptosis in HASMCs. We therefore suggest that ER stress participates in PTH-induced apoptosis of VSMCs, which may be a possible mechanism of PTH-promoted vascular calcification in CKD patients.

Proteomics reveals the potential mechanism of Mrps35 controlling Listeria monocytogenes intracellular proliferation in macrophages.

Macrophages are sentinels in the organism which can resist and destroy various bacteria through direct phagocytosis. Here, we reported that expression level of mitochondrial ribosomal protein S35 (Mrps35) continued to decrease over infection time after Listeria monocytogenes (L. monocytogenes) infected macrophages. Our results indicated that knockdown Mrps35 increased the load of L. monocytogenes in macrophages. This result supported that Mrps35 played the crucial roles in L. monocytogenes infection. Moreover, we performed the comprehensive proteomics to analyze the differentially expressed protein of wild type and Mrps35 Knockdown Raw264.7 cells by L. monocytogenes infection over 6 h. Based on the results of mass spectrometry, we presented a wide variety of hypotheses about the mechanism of Mrps35 controlling the L. monocytogenes intracellular proliferation. Among them, experiments confirmed that Mrps35 and 60S ribosomal protein L22-like 1 (Rpl22l1) were a functional correlation or potentially a compensatory mechanism during L. monocytogenes infection. This study provided new insights into understanding that L. monocytogenes infection changed the basic synthesis or metabolism-related proteins of host cells.

Bioactive peptide apelin rescues acute kidney injury by protecting the function of renal tubular mitochondria.

Mitochondrial dysfunction in proximal tubular epithelial cells is a key event in acute kidney injury (AKI), which is a risk factor for the development of chronic kidney disease (CKD). Apelin is a bioactive peptide that protects against AKI by alleviating inflammation, inhibiting apoptosis, and preventing lipid oxidation, but its role in protecting against mitochondrial damage remains unknown. Herein, we examined the protective effects of apelin on mitochondria in cisplatin-stimulated human renal proximal tubular epithelial cells and evaluated its therapeutic efficacy in cisplatin-induced AKI mice. In vitro, apelin inhibited the cisplatin-induced mitochondrial fission factor (MFF) upregulation and the fusion-promoting protein optic atrophy 1 (OPA1) downregulation. Apelin co-treatment reversed the decreased levels of the deacetylase, Sirt3, and the increased levels of protein acetylation in mitochondria of cisplatin-stimulated cells. Overall, apelin improved the mitochondrial morphology and membrane potential in vitro. In the AKI model, apelin administration significantly attenuated mitochondrial damage, as evidenced by longer mitochondrial profiles and increased ATP levels in the renal cortex. Suppression of MFF expression, and maintenance of Sirt3 and OPA1 expression in apelin-treated AKI mice was also observed. Finally, exogenous administration of apelin normalized the serum level of creatinine and urea nitrogen and the urine levels of NGAL and Kim-1. We also confirmed a regulatory pathway that drives mitochondrial homeostasis including PGC-1α, ERRα and Sirt3. In conclusion, we demonstrated that apelin ameliorates renal functions by protecting tubular mitochondria through Sirt3 upregulation, which is a novel protective mechanism of apelin in AKI. These results suggest that apelin has potential renoprotective effects and may be an effective agent for AKI treatment to significantly retard CKD progression.

Secreted Frizzled-Related Protein 5 Ameliorates Vascular Calcification in a Rat Model of Chronic Kidney Disease through the Wnt/ß-Catenin Pathway.

INTRODUCTION: Vascular calcification (VC) is highly prevalent and a major cardiovascular risk factor in chronic kidney disease (CKD) patients. Secreted frizzled-related protein 5 (SFRP5), an inhibitor of the Wnt pathway, is an adipokine with a positive effect on metabolic and cardiovascular diseases. Our previous in vitro study showed that SFRP5 attenuates high phosphate-induced calcification in vascular smooth muscle cells by inhibiting the Wnt/ß-catenin pathway. Therefore, we hypothesized that SFRP5 may protect against CKD-associated VC (CKD-VC) through the same signalling. METHODS: The rat model of CKD with VC was induced by 0.75% adenine combined with 1.8% high phosphate diet, which were administered with adenovirus vectors of SFRP5. We evaluated the SFRP5 effect on VC by von Kossa staining and calcium content analysis and osteogenic markers by immunohistochemistry and Western blot. The components of Wnt/ß-catenin signalling were also evaluated. RESULTS: SFRP5 local and serum levels were significantly decreased in the CKD-VC rat model compared with the control group. Adenovirus-mediated overexpression of SFRP5 significantly inhibited VC, which was due to suppression of CKD-induced expression of calcification and osteoblastic markers. Additionally, SFRP5 abrogated activation of the Wnt/ß-catenin pathway that plays a major role in the pathogenesis of VC. The specificity of SFRP5 for inhibition of VC was confirmed using an empty adenovirus as a control. CONCLUSION: Our results suggest that SFRP5 ameliorates VC of CKD rats by inhibiting the expression of calcification and osteoblastic markers as well as the Wnt/ß-catenin pathway. Collectively, this study suggests that SFRP5 is a potential therapeutic target in CKD-VC.

Microwave ablation versus parathyroidectomy for severe secondary hyperparathyroidism in patients on hemodialysis: a retrospective multicenter study.

BACKGROUND: Microwave ablation is effective for severe secondary hyperparathyroidism, but the difference in efficacy between microwave ablation and parathyroidectomy remains unclear. In this multicenter retrospective cohort study, we compared the long-term clinical efficacy of microwave ablation and parathyroidectomy for severe secondary hyperparathyroidism undergoing hemodialysis. MATERIALS AND METHODS: The patients were divided into microwave ablation and parathyroidectomy groups. The primary endpoint was the proportion of patients with intact parathyroid hormone (iPTH) concentrations within the target range (100-600 pg/mL) during the efficacy assessment phase. The secondary endpoints were (i) differences in iPTH concentrations over time between the two groups, and (ii) decreases in iPTH concentrations over time in the two groups. RESULTS: Microwave ablation was performed in 47/92 patients and parathyroidectomy in 45/92. Primary endpoint: iPTH concentrations within the target range were achieved during the efficacy assessment phase in 26/47 patients (55.3%) and in 14/45 (31.1%) patients in the microwave ablation and parathyroidectomy groups, respectively (p = .02). Secondary endpoints: (i) Mean iPTH concentrations during the efficacy assessment phase were significantly higher in the microwave ablation versus parathyroidectomy groups (649 ± 519 pg/mL versus 136 ± 228 pg/mL, respectively; p < .01). (ii) Mean decrease in iPTH concentration from baseline was 725 ± 605 pg/mL versus 1369 ± 478 pg/mL in the MWA versus parathyroidectomy groups, respectively (p < .01). CONCLUSIONS: Ultrasound-guided percutaneous microwave ablation provides higher iPTH target-achieving rates than parathyroidectomy in patients with severe secondary hyperparathyroidism undergoing hemodialysis.