Tubular-specific expression of HIV protein Vpr leads to severe tubulointerstitial damage accompanied by progressive fibrosis and cystic development.

Chronic kidney disease (CKD) is a common cause of morbidity in human immunodeficiency virus (HIV)-positive individuals. HIV infection leads to a wide spectrum of kidney cell damage, including tubular epithelial cell (TEC) injury. Among the HIV-1 proteins, the pathologic effects of viral protein R (Vpr) are well established and include DNA damage response, cell cycle arrest, and cell death. Several in vitro studies have unraveled the molecular pathways driving the cytopathic effects of Vpr in tubular epithelial cells. However, the in vivo effects of Vpr on tubular injury and CKD pathogenesis have not been thoroughly investigated. Here, we use a novel inducible tubular epithelial cell-specific Vpr transgenic mouse model to show that Vpr expression leads to progressive tubulointerstitial damage, interstitial inflammation and fibrosis, and tubular cyst development. Importantly, Vpr-expressing tubular epithelial cells displayed significant hypertrophy, aberrant cell division, and atrophy; all reminiscent of tubular injuries observed in human HIV-associated nephropathy (HIVAN). Single-cell RNA sequencing analysis revealed the Vpr-mediated transcriptomic responses in specific tubular subsets and highlighted the potential multifaceted role of p53 in the regulation of cell metabolism, proliferation, and death pathways in Vpr-expressing tubular epithelial cells. Thus, our study demonstrates that HIV Vpr expression in tubular cells is sufficient to induce HIVAN-like tubulointerstitial damage and fibrosis, independent of glomerulosclerosis and proteinuria. Additionally, as this new mouse model develops progressive CKD with diffuse fibrosis and kidney failure, it can serve as a useful tool to examine the mechanisms of kidney disease progression and fibrosis in vivo.

Risk Factors and Drug Efficacy for Severe Illness in Hemodialysis Patients Infected with the Omicron Variant of COVID-19.

INTRODUCTION: The Omicron variant of the novel coronavirus (COVID-19) has been spreading more rapidly and is more infectious, posing a higher risk of death and treatment difficulty for patients undergoing hemodialysis. This study aims to explore the severity rate and risk factors for hemodialysis patients infected with the Omicron variant and to conduct a preliminary analysis of the clinical efficacy of drugs. METHODS: Clinical and biochemical indicators of 219 hemodialysis patients infected with the Omicron variant were statistically analyzed. The patients were divided into two groups based on whether they were severely ill or not, and multiple regression analysis was conducted to determine the risk factors for severe illness. The severely ill patients were then grouped based on discharge or death, and the treatment drugs were included as influencing factors for multiple regression analysis to determine the risk factors and protective factors for death of severely ill patients, and drug efficacy analysis was conducted. RESULTS: Analysis showed that diabetes, low oxygen saturation, and high C-reactive protein (CRP) were independent risk factors for severe illness in hemodialysis patients infected with the Omicron variant. A history of diabetes and high C-reactive significantly increased the risk of severe illness in patients (aOR: 1.450; aOR: 1.011), while a high oxygen saturation level can reduce this risk (aOR: 0.871). In addition, respiratory distress was an independent risk factor for death in severely patients, significantly reducing the probability of discharge for patients (aOR: 0.152). The drugs thymalfasin and Tanreqing significantly increased the probability of discharge for patients (aOR: 1.472; aOR: 3.104), with the latter having a higher correlation, but with a relatively longer effective course. CONCLUSION: Hemodialysis patients infected with the Omicron variant of COVID-19 should pay special attention to their history of diabetes, CRP, and oxygen saturation levels, as well as respiratory distress symptoms, to reduce the risk of severe illness and death. In addition, thymalfasin and Tanreqing may be considered in treatment.

Kidney single-cell transcriptome profile reveals distinct response of proximal tubule cells to SGLT2i and ARB treatment in diabetic mice.

Angiotensin receptor blockers (ARBs) and sodium-glucose cotransporter 2 inhibitors (SGLT2i) have been used as the standard therapy for patients with diabetic kidney disease (DKD). However, how these two drugs possess additive renoprotective effects remains unclear. Here, we conducted single-cell RNA sequencing to profile the kidney cell transcriptome of db/db mice treated with vehicle, ARBs, SGLT2i, or ARBs plus SGLT2i, using db/m mice as control. We identified 10 distinct clusters of kidney cells with predominant proximal tubular (PT) cells. We found that ARBs had more anti-inflammatory and anti-fibrotic effects, while SGLT2i affected more mitochondrial function in PT. We also identified a new PT subcluster, was increased in DKD, but reversed by the treatments. This new subcluster was also confirmed by immunostaining of mouse and human kidneys with DKD. Together, our study reveals kidney cell-specific gene signatures in response to ARBs and SGLT2i and identifies a new PT subcluster, which provides new insight into the pathogenesis of DKD.

Total cholesterol and mortality in peritoneal dialysis: a retrospective cohort study.

BACKGROUND: Total cholesterol is inversely associated with mortality in dialysis patients, which seems implausible in real-world clinical practice. May there be an optimal range of total cholesterol associated with a lower mortality risk? We aimed to evaluate the optimal range for peritoneal dialysis (PD) patients. METHODS: We conducted a retrospective real-world cohort study of 3565 incident PD patients from five PD centers between January 1, 2005, and May 31, 2020. Baseline variables were collected within one week before the start of PD. The associations between total cholesterol and mortality were examined using cause-specific hazard models. RESULTS: 820 (23.0%) patients died, including 415 cardiovascular deaths, during the follow-up period. Restricted spline plots showed a U-curved association of total cholesterol with mortality. Compared with the reference range (4.10-4.50 mmol/L), high levels of total cholesterol (> 4.50 mmol/L) were associated with increased risks of all-cause (hazard ratio [HR] 1.35, 95% confidence index [CI] 1.08-1.67) and cardiovascular mortality (HR 1.38, 95% CI 1.09-1.87). Similarly, compared with the reference range, low levels of total cholesterol (< 4.10mmol/L) were also associated with high risks of all-cause (HR 1.62, 95% CI 1.31-1.95) and cardiovascular mortality (HR 1.72, 95% CI 1.27-2.34). CONCLUSION: Total cholesterol levels at the start of PD between 4.10 and 4.50 mmol/L (158.5 to 174.0 mg/dL), an optimal range, were associated with lower risks of death than higher or lower levels, resulting in a U-shaped association.

Association between disability in activities of daily living and phase angle in hemodialysis patients.

BACKGROUND: Disability in activities of daily living (ADL) significantly increases the risk of mortality among patients undergoing hemodialysis. Malnutrition and decreased exercise capacity are closely correlated with ADL disability. Phase angle (PhA) has been proposed as a measure of nutritional status and exercise capacity. This study aims to investigate the prevalence of ADL disability in hemodialysis patients and its association with PhA. METHODS: A prospective, observational study was conducted, involving hemodialysis patients treated between November 2019 and January 2020 in an affiliated hospital of Chinese university. ADL was measured using both basic ADL (BADL) scales and instrumental ADL (IADL) scales. PhA measurements were obtained using a BIA device while the patients were in the supine position after dialysis. RESULTS: A total of 237 hemodialysis patients with a mean age of 60.01 ± 13.55 years were included in this study. The prevalence of disability in ADL was 43.5%. Multivariable analysis results showed a robust association between low PhA and disability in both BADL and IADL (for each unit decrease in PhA: odds ratio 4.83 [95% CI: 2.56-9.0], and 3.57 [95% CI: 2.14-5.95], respectively). The optimal cut-off values of PhA for disability in BADL and IADL were 4.8 and 5.4, with the area under the ROC curve (AUC) were 0.783 (0.727, 0.835) and 0.799 (0.743, 0.848), respectively. CONCLUSIONS: Low PhA is strongly associated with disability in ADL in hemodialysis patients. These findings suggest that PhA may serve as a potentially objective measure of ADL disability in hemodialysis patients.

The Effects of Fluid Hydration Status on Ultrasound Muscle Measurement in Hemodialysis Patients.

OBJECTIVE: This study aimed to explore the effects of fluid hydration status on ultrasound muscle measurement in hemodialysis (HD) patients. METHODS: Ultrasound muscle examination of the right rectus femoris and bioelectrical impedance analysis measurement of the right lower limb were performed in HD patients at the periods of predialysis and postdialysis. The correlations between the changes in the corresponding ultrasound and bioelectrical impedance analysis variables were analyzed. RESULTS: A total of 50 patients on maintenance HD were included, with mean age of 52.6 ± 13.5 years. Patients were 40% female (n = 20), and average dialysis duration was 2.62 ± 2.42 years. Compared to predialysis, the measurements of cross-sectional area, muscle thickness, echo intensity (EI), and their percentage changes all decreased significantly after the HD procedure (P < .05). The change in EI and its percentage change were significantly correlated with changes in total body water, intracellular water, and extracellular water (P < .05). CONCLUSIONS: The HD session may have significant effects on ultrasound muscle measurement. Both the indicators of muscle quantity (cross-sectional area and muscle thickness) and quality (EI) significantly decreased after HD, which may contribute to the change in fluid hydration status and the change in fluid composition.

[Discussions Concerning the Generalist-Specialist Combination Management Model of Chronic Kidney Disease]. / æ ¢æ€§è‚¾è„ç— "å ¨-专"结合管理模式探讨.

In recent years, the effective management of patients with chronic kidney disease (CKD) is gaining growing attention. In 2014, our hospital established the CKD generalist-specialist combination management model, which incorporates a set of CKD management processes. The generalist component incorporates the following, general practitioners from 6 community health centers in the surrounding areas (with about 650 000 permanent residents in the region) joining hands, setting up a management team composed of doctors and nurses, and formulating management protocols for patient follow-up, patient record management, screening, risk assessment, examination and treatment, nutrition and exercise, and two-way referrals. The specialist component of the model incorporates the following, providing trainings for general practitioners in the in the community in the form of lectures on special topics and case discussion sessions, and organizing 7 national-level workshops for continuing medical education in the past decade, covering about 1 400 participants. In addition, regular meetings of the support groups of patients with renal diseases were organized to carry out information and education activities for patients. We have set up 4 community-based training centers and 6 specialized disease management centers, including one for diabetic nephropathy. We have retrospectively analyzed the risk factors of elderly CKD patients by establishing the elderly physical examination database (which has a current enrollment of 26 000 people), the elderly community CKD cross-sectional survey database, and the elderly CKD information management system. After 10 years of management practice, the level of institutionalization and standardization of CKD specialty management in our hospital has been improved. Moreover, we have expanded the management team and extended the management base from the hospital to community. We have improved the level of CKD management in community health centers and improved the specialty competence of the general practitioners in the communities. The generalist-specialist combination management model makes it possible for CKD patients to receive early screening and treatment, obtain effective and convenient follow-up and referral services, and improve their quality of life. Patients with complications such as diabetes, hypertension, and sarcopenia could access treatments with better precision. It is necessary to carry out the generalist-specialist integrated management of CKD, which is worthy of further development and improvement.

Relationships among the Dosage of Erythropoiesis-Stimulating Agents, Erythropoietin Resistance Index, and Mortality in Maintenance Hemodialysis Patients.

BACKGROUND: Erythropoiesis-stimulating agents (ESAs) constitute an important treatment option for anemia in hemodialysis (HD) patients. We investigated the relationships among the dosage of ESA, erythropoietin resistance index (ERI) scores, and mortality in Chinese MHD patients. METHODS: This multicenter observational retrospective study included MHD patients from 16 blood purification centers (n = 824) who underwent HD in 2011-2015 and were followed up until December 31, 2016. We collected demographic variables, HD parameters, laboratory values, and ESA dosages. Patients were grouped into quartiles according to ESA dosage to study the effect of ESA dosage on all-cause mortality. The ERI was calculated as follows: ESA (IU/week)/weight (kg)/hemoglobin levels (g/dL). We also compared outcomes among the patients stratified into quartiles according to ERI scores. We used the Cox proportional hazards model to measure the relationships between the ESA dosage, ERI scores, and all-cause mortality. Using propensity score matching, we compared mortality between groups according to ERI scores, classified as either > or ≤12.80. RESULTS: In total, 824 patients were enrolled in the study; 200 (24.3%) all-cause deaths occurred within the observation period. Kaplan-Meier analyses showed that patients administered high dosages of ESAs had significantly worse survival than those administered low dosages of ESAs. A multivariate Cox regression identified that high dosages of ESAs could significantly predict mortality (ESA dosage >10,000.0 IU/week, HR = 1.59, 95% confidence intervals (CIs) (1.04, 2.42), and p = 0.031). Our analysis also indicated a significant increase in the risk of mortality in patients with high ERI scores. Propensity score matching-analyses confirmed that ERI > 12.80 could significantly predict mortality (HR = 1.56, 95% CI [1.11, 2.18], and p = 0.010). CONCLUSIONS: Our data suggested that ESA dosages >10,000.0 IU/week in the first 3 months constitute an independent predictor of all-cause mortality among Chinese MHD patients. A higher degree of resistance to ESA was related to a higher risk of all-cause mortality.

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.

Enhanced echo intensity of skeletal muscle is associated with poor physical function in hemodialysis patients: a cross-sectional study.

BACKGROUND: Patients on hemodialysis often suffer from reduced muscle strength and exercise capacity due to the decreased quantity and quality of muscle. Cumulative studies showed ultrasound echo intensity (EI) had great potential in evaluating muscle quality. The objective of this study was to evaluate the relationship between EI of skeletal muscle and physical function of patients on maintenance hemodialysis. METHODS: Cross-sectional area (CSA) and mean EI of the right rectus femoris were measured by ultrasound to evaluate the quantity and quality of the muscle, respectively. Physical function was measured by handgrip strength (HGS), gait speed, sit-to-stand 60 s (STS-60) test, and instrumental activities of daily living (IADL) scale. RESULTS: A total of 107 patients on hemodialysis were included, with women accounting for 37.3% (n = 40), and a mean age of 53.53 ± 12.52 years. Among the patients on hemodialysis, EI was moderately and negatively correlated with HGS (r = - 0.467, P < 0.001), gait speed (r = - 0.285, P = 0.003), and STS-60 (r = - 0.313, P = 0.001). Multiple regression analyses adjusted for CSA showed that the enhanced EI of patients on hemodialysis remained associated with worse HGS (ß = - 0.207, P = 0.047), lower gait speed (ß = - 0.002, P = 0.001), less STS-60 (ß = - 0.136, P = 0.049), and a higher likelihood of dependency in IADL (Odds Ratio: 1.070, 95% CI: [1.033-1.111], P = 0.001). CONCLUSIONS: In patients on hemodialysis, enhanced EI in the skeletal muscle measured via ultrasound was correlated with poor physical performance. The combined muscle quality and muscle quantity evaluation provide more information for assessing the level of physical function of the patients.

Hyperlipidemia and mortality in patients on peritoneal dialysis.

BACKGROUND: New lipid-lowering therapy at the start of dialysis and measurement of lipid parameters over the follow-up period is not recommended in dialysis patients, which seems unappropriated in clinical practice. We aimed to examine the effect of hyperlipidemia on mortality in patients undergoing continuous ambulatory peritoneal dialysis (CAPD). METHODS: A retrospective cohort study was performed, including 2939 incident CAPD patients from five dialysis facilities between January 1, 2005, and December 31, 2018. The primary outcome was all-cause mortality. The association between hyperlipidemia at the start of CAPD and all-cause mortality was evaluated using Cox proportional hazards regression. RESULTS: Of 2939 with a median age of 50.0 (interquartile range, 39.0-61.0), 1697 (57.7%) were men, 533 (18.1%) had hyperlipidemia, 549 (18.7%) had diabetes mellitus, 1915 (65.2%) had hypertension, and 410 (14.0%) had a history of CVD. During the median follow-up period of 35.1 months, 519 (17.7%) died, including 402 (16.7%, 47.4/1000 patient-years) in the non-hyperlipidemia group and 117 (22.0%, 71.1/1000 patient-years) in the hyperlipidemia group. Over the overall follow-up period, patients with hyperlipidemia had an equally high risk of all-cause mortality throughout follow-up as those without hyperlipidemia ([HR] 1.04, 95% confidence interval [CI] 0.83 to 1.31). However, from the 48-month follow-up onwards, hyperlipidemia was associated with a 2.26 (95% CI 1.49 to 3.43)-time higher risk of all-cause mortality than non-hyperlipidemia. Hypertension modified the association between hyperlipidemia and all-cause mortality (P for interaction < 0.001). A significantly increased risk of all-cause mortality was observed among patients with hypertension (HR 2.27, 95%CI 1.44-3.58). CONCLUSION: Among CAPD patients, hyperlipidemia at the beginning of CAPD was associated with a high risk of long-term mortality. Hypertension may mediate the association. Our findings suggested that long-term lipid-lowering treatment should be used in those patients with hyperlipidemia.

Coexistence of diabetes mellitus and pre-existing cardiovascular disease and mortality in Chinese patients on peritoneal dialysis.

BACKGROUND: Little is known about the association between the coexistence of diabetes mellitus (DM) and pre-existing cardiovascular disease (CVD) and mortality in patients undergoing continuous ambulatory peritoneal dialysis (CAPD). METHODS: A retrospective cohort study of 2939 Chinese incident CAPD patients was conducted between January 1, 2005, and December 31, 2018. The primary and secondary outcomes were all-cause and CVD mortality. The association between the coexistence of DM and pre-existing CVD and mortality was evaluated using Cox proportional hazards regression. RESULTS: Over a median of 35.1 months of follow-up, 519 patients (17.7%) died, with 258 (8.8%) being CVD-related deaths. DM plus pre-existing CVD, DM, and pre-existing CVD were associated with a higher risk of all-cause mortality (adjusted hazard ratio [HR], 2.85; 95% confidence interval [CI], 2.18 to 3.72; adjusted HR, 1.89; 95% CI, 1.50 to 2.38; and HR, 1.43; 95% CI, 1.07 to 1.92; P for tend < 0.001) and CVD mortality (adjusted HR, 2.79; 95% CI, 1.91 to 4.08; HR, 1.88; 95% CI, 1.35 to 2.61; and HR, 1.82; 95% CI, 1.23 to 2.68; P for trend < 0.001) than no DM or pre-existing CVD. Subgroup analyses stratified by sex, hypertension status, and hyperlipidemia status showed a similar pattern. CONCLUSIONS: The coexistence of DM and pre-existing CVD at the start of CAPD was more strongly associated with a higher risk of all-cause and CVD mortality than DM or pre-existing CVD alone.

Dl-3-n-butylphthalide pretreatment attenuates renal ischemia/reperfusion injury.

BACKGROUND: Renal ischemia reperfusion injury (IRI) has become a growing concern in clinical practice with high morbidity and mortality rates. There is currently no effective prophylactic regimen available to prevent its occurrence and to improve its clinical prognosis. Dl-3-n-butylphthalide (NBP) has been used for stroke treatment in China for years. Little is known about its role in preventing kidney injury. METHODS: The kidneys of male C57BL/6J mice were subjected to 33 min of ischemia followed by 24 h of reperfusion. NBP was administered by gavage prior to surgery. The reno-protective effect of NBP was evaluated by serum creatinine, kidney injury markers and renal pathological changes. Furthermore, the inflammation, oxidative stress, and apoptosis markers in kidney tissue were examined. In vitro, HK2 cells were treated prophylactically with NBP and then exposed to hypoxia/reoxygenation (H/R). Cell viability and apoptosis related protein were quantified to verify the protective effect of NBP. Pro-inflammation genes expression as well as ROS generation were further investigated also. RESULTS: NBP pretreatment significantly improved renal dysfunction and alleviated pathological injury, renal inflammation response, oxidative stress and cell apoptosis. Consistently, NBP attenuated H/R induced increases in ROS, pro-inflammatory genes expression, apoptosis and cleaved caspase-3 levels in HK2 cells. CONCLUSION: Our promising results validated for the first time that NBP could ameliorate renal IRI via attenuating inflammation, oxidative stress, and apoptosis, which indicated that NBP might be a good candidate against AKI.

Sitagliptin ameliorates renal tubular injury in diabetic kidney disease via STAT3-dependent mitochondrial homeostasis through SDF-1α/CXCR4 pathway.

Mitochondrial abnormalities play critical roles in diabetic tubular injury progression. Dipeptidyl peptidase-4 (DPP4) inhibitors are widely used antihyperglycemic agents that exert renal protective and positive effects against mitochondrial dysfunction in diabetic kidney disease (DKD). However, their underlying mechanism remains unclear. In this study, DPP4 upregulation, mitochondrial fragmentation, and altered mitochondrial dynamics-associated protein expression were observed in the tubules of DBA2/J (D2) diabetic mice with unilateral nephrectomy and in albumin-stimulated tubular cells. The inhibition of DPP4 by sitagliptin (Sita) ameliorated these mitochondrial perturbations both in vivo and in vitro, whereas DPP4 overexpression aggravated mitochondrial fusion-fission disorder and tubular cell injury in albumin-treated HK-2 cells. Downstream of DPP4, the SDF-1α/CXCR4 pathway was significantly suppressed in diabetic tubules. After Sita treatment, this signaling pathway was restored, and the mitochondrial dynamics was improved. Furthermore, a direct interaction between STAT3 and OPA1 was found in the mitochondria of tubular cells, and this effect was weakened by overloading albumin and by CXCR4 siRNA treatment, suggesting a possible link between DPP4-mediated SDF-1α/CXCR4/STAT3 signaling and mitochondrial dysfunction in diabetic tubular cells. The results suggest that a novel mechanism links the DPP4 enzyme to impaired mitochondrial dynamics homeostasis during tubular injury in DKD and highlight that the SDF-1α/CXCR4/STAT3 signaling pathway could become a potential target for managing DKD.

Association Between Sarcopenia and Its Components and Dependency in Activities of Daily Living in Patients on Hemodialysis.

OBJECTIVES: To investigate the association of sarcopenia and its components (muscle mass, muscle strength, and physical performance) with dependency in activities of daily living (ADLs) in maintaining patients on hemodialysis. DESIGN AND METHODS: This is a cross-sectional study. Sarcopenia was identified according to the Asian Working Group for Sarcopenia 2019 criteria. Basic ADLs (BADLs) and instrumental ADLs (IADLs) were assessed. Logistic regression was used to estimate the association of sarcopenia and its components with dependency. Area under the receiver-operating characteristic curve of gait speed corresponding with dependency was calculated. RESULTS: A total of 238 patients on hemodialysis were included. The proportion of enrolled male candidates was 67.6%, and the average age was 60.9 years. In all, 49.2% (n = 117) and 30.7% (n = 73) of patients on dialysis were diagnosed with sarcopenia and severe sarcopenia, respectively. Dependency in BADLs was 21.0% (n = 50), and dependency in IADLs was 41.2% (n = 98). Severe sarcopenia was significantly associated with dependency in BADLs and IADLs after adjustment of clinical covariables (odds ratio [OR], 4.68 [95% confidence interval (CI): 2.11-10.40]; OR, 3.24 [95% CI: 1.61-6.53], respectively), whereas those effects for sarcopenia were not significant. With all three sarcopenia components in the analysis model, high gait speed remained strongly associated with low function dependency in BADLs and IADLs (per 0.1 m/s increase of gait speed: OR, 0.52 [95% CI: 0.41-0.66]; and 0.46 [95% CI: 0.35-0.59], respectively). Area under the receiver-operating characteristic curve of gait speed corresponding with dependency in BADLs and IADLs was 0.827 (0.759, 0.896) and 0.878 (0.832, 0.925), respectively. CONCLUSIONS: Severe sarcopenia was closely related to dependency in ADL in patients on hemodialysis. Gait speed was the most important factor affecting dependency in sarcopenia and had good diagnostic accuracy for screening dependency in ADL.

Endogenous miR-204 Protects the Kidney against Chronic Injury in Hypertension and Diabetes.

BACKGROUND: Aberrant microRNA (miRNA) expression affects biologic processes and downstream genes that are crucial to CKD initiation or progression. The miRNA miR-204-5p is highly expressed in the kidney but whether miR-204-5p plays any role in the development of chronic renal injury is unknown. METHODS: We used real-time PCR to determine levels of miR-204 in human kidney biopsies and animal models. We generated Mir204 knockout mice and used locked nucleic acid-modified anti-miR to knock down miR-204-5p in mice and rats. We used a number of physiologic, histologic, and molecular techniques to analyze the potential role of miR-204-5p in three models of renal injury. RESULTS: Kidneys of patients with hypertension, hypertensive nephrosclerosis, or diabetic nephropathy exhibited a significant decrease in miR-204-5p compared with controls. Dahl salt-sensitive rats displayed lower levels of renal miR-204-5p compared with partially protected congenic SS.13BN26 rats. Administering anti-miR-204-5p to SS.13BN26 rats exacerbated interlobular artery thickening and renal interstitial fibrosis. In a mouse model of hypertensive renal injury induced by uninephrectomy, angiotensin II, and a high-salt diet, Mir204 gene knockout significantly exacerbated albuminuria, renal interstitial fibrosis, and interlobular artery thickening, despite attenuation of hypertension. In diabetic db/db mice, administering anti-miR-204-5p exacerbated albuminuria and cortical fibrosis without influencing blood glucose levels. In all three models, inhibiting miR-204-5p or deleting Mir204 led to upregulation of protein tyrosine phosphatase SHP2, a target gene of miR-204-5p, and increased phosphorylation of signal transducer and activator of transcription 3, or STAT3, which is an injury-promoting effector of SHP2. CONCLUSIONS: These findings indicate that the highly expressed miR-204-5p plays a prominent role in safeguarding the kidneys against common causes of chronic renal injury.

IL-17C has a pathogenic role in kidney ischemia/reperfusion injury.

Cytokines are necessary to trigger the inflammatory response in kidney ischemia/reperfusion injury. Interleukin-17C (IL-17C), a unique member of the IL-17 family, is a cytokine produced by epithelial cells implicated in host defense and autoimmune diseases. However, little is known about the role of IL-17C in acute kidney injury. We investigated this and found that IL-17C was significantly increased in kidney biopsies of patients and mice with acute kidney injury. Exposure to hypoxia induced upregulation of IL-17C in kidney tubular epithelial cells. To further investigate the role of IL-17C, kidney ischemia/reperfusion injury was induced in mice. Inhibition of IL-17C action with a neutralizing antibody or IL-17 receptor E (IL-17RE) knockout attenuated tubular injury, kidney oxidative stress, and kidney inflammation. Mechanistically, both IL-17C neutralization and IL-17RE knockout attenuated TH17 activation and IL-17A expression in kidneys of mice with acute kidney injury. TNF-α and IL-1ß, downstream cytokines of IL-17C, were also reduced in IL-17C antibody pretreated and IL-17RE knockout mice. Additionally, IL-17C knockdown with siRNA decreased hypoxia-induced inflammation in kidney tubular cells and silencing IL-17RE abrogated the effects of IL-17C in kidney tubular cells. Thus, IL-17C may participate in the inflammatory response of acute kidney injury and inhibition of IL-17C or blockade of IL-17 RE may be a novel therapeutic strategy for the treatment of acute kidney injury.

A protective role of renalase in diabetic nephropathy.

Renalase, a recently discovered secreted flavoprotein, exerts anti-apoptotic and anti-inflammatory effects against renal injury in acute and chronic animal models. However, whether Renalase elicits similar effects in the development of diabetic nephropathy (DN) remains unclear. The studies presented here tested the hypothesis that Renalase may play a key role in the development of DN and may have therapeutic potential for DN. Renalase expression was measured in human kidney biopsies with DN and in kidneys of db/db mice. The role of Renalase in the development of DN was examined using a genetically engineered mouse model: Renalase knockout mice with db/db background. The renoprotective effects of Renalase in DN was evaluated in db/db mice with Renalase overexpression. In addition, the effects of Renalase on high glucose-induced mesangial cells were investigated. Renalase was down-regulated in human diabetic kidneys and in kidneys of db/db mice compared with healthy controls or db/m mice. Renalase homozygous knockout increased arterial blood pressure significantly in db/db mice while heterozygous knockout did not. Renalase heterozygous knockout resulted in elevated albuminuria and increased renal mesangial expansion in db/db mice. Mesangial hypertrophy, renal inflammation, and pathological injury in diabetic Renalase heterozygous knockout mice were significantly exacerbated compared with wild-type littermates. Moreover, Renalase overexpression significantly ameliorated renal injury in db/db mice. Mechanistically, Renalase attenuated high glucose-induced profibrotic gene expression and p21 expression through inhibiting extracellular regulated protein kinases (ERK1/2). The present study suggested that Renalase protected against the progression of DN and might be a novel therapeutic target for the treatment of DN.

Poor Renal and Cardiovascular Outcomes in Patients with Biopsy-Proven Diabetic Nephropathy.

BACKGROUND: Despite the high mortality of cardiovascular disease (CVD) in diabetic patients with renal injury, few studies have compared cardiovascular characteristics and outcomes between patients with diabetic nephropathy (DN) and non-diabetic renal disease (NDRD). METHODS: A total of 326 type 2 diabetes mellitus patients with renal biopsy were assigned to DN and NDRD groups. Echocardiography and Doppler ultrasound were performed to evaluate left ventricular hypertrophy (LVH) and peripheral atherosclerosis disease (PAD). Renal and cardiovascular survival rates were compared between the DN and NDRD groups by Kaplan-Meier analysis. Risk factors for renal and cardiovascular events in DN patients were identified by a Cox proportional hazards model. RESULTS: In total, 179 patients entered the DN group (54.9%) and 147 made up the NDRD group (45.1%). The presence of diabetic retinopathy, family history of diabetes, and dependence on insulin therapy were associated with the presence of DN. DN patients had more CVD with more severe LVH and PAD. Poorer renal (log-rank χ2 = 26.534, p < 0.001) and cardiovascular (log-rank χ2 = 16.257, p < 0.001) prognoses were seen in the DN group. DR (HR 1.539, 95% CI 1.332-1.842), eGFR (HR 0.943, 95% CI 0.919-0.961), and 24-h proteinuria (HR 1.211, 95% CI 1.132-1.387) were identified as risk factors for renal endpoints. Age (HR 1.672, 95% CI 1.487-1.821), HbA1C (HR 1.398, 95% CI 1.197-1.876), and 24-h proteinuria (HR 1.453, 95% CI 1.289-1.672) were associated with cardiovascular endpoints. CONCLUSION: Patients with DN had more severe CVD along with poorer renal and cardiovascular prognoses than those with NDRD.

Influence of therapeutic drugs on different manifestations of renal involvement in 907 Chinese patients with ankylosing spondylitis
.

BACKGROUND: There is no systematic or large-scale study in the published literature in which the relationship between drug therapies and renal involvement in ankylosing spondylitis (AS) has been rigorously evaluated. In addition, the sensitivity of the kidneys to drugs varies significantly between races and regional populations. Therefore, the aim of the present study was to investigate the impact of drugs on renal involvement in Chinese AS patients. MATERIALS AND METHODS: The clinical characteristics and biochemical data of 907 AS patients were collected and analyzed, and the differences between patients who had received drugs and those who had not were analyzed using intergroup comparisons to screen out confounding factors. Multivariate logistic regression analysis that corrected for the confounding factors explored the impact of the AS therapeutic drugs on the clinical manifestations of renal involvement. RESULTS: Renal involvement in Chinese AS patients increased significantly following non-steroidal anti-inflammatory drug (NSAID) or conventional synthetic disease-modifying anti-rheumatic drug (csDMARD) monotherapy, and combination therapy with NSAIDs, csDMARDs, and TNF-α inhibitor. For AS patients, NSAID monotherapy increased the probability of hematuria 2.4-fold and the probability of mixed manifestations of renal involvement 3.0-fold. csDMARD monotherapy increased the probability of proteinuria 2.4-fold; combination therapy with NSAIDs, csDMARDs, and TNF-α inhibitor increased the probability of hematuria 4.1-fold. In addition, the study found that TNF-α inhibitor monotherapy and combination therapy with NSAIDs or csDMARDs caused no apparent impact on renal involvement in AS patients. CONCLUSION: NSAID or csDMARD monotherapy may significantly increase renal involvement in Chinese AS patients. Combination therapy with TNF-α inhibitor with NSAIDs and csDMARDs should be used prudently.