Association of Frailty With Nutritional Status in Patients With Chronic Kidney Disease.

OBJECTIVES: Frailty is commonly observed in patients with chronic kidney disease (CKD) and is associated with adverse outcomes. Protein-energy wasting (PEW), a state of decreased body stores of protein and energy fuels, may be associated with frailty. However, few data are available on the possible association between frailty and PEW in CKD. METHODS: We examined the association between frailty and nutritional status assessed using anthropometric and body composition measurements, serum albumin, handgrip strength, the Malnutrition Inflammation Score (MIS), and dietary protein and calorie intake in a cross-sectional analysis of nondialysis patients with CKD stages 3-5. Body composition was assessed using multifrequency bioelectrical impedance. Frailty was defined as a Clinical Frailty Scale ≥4. We performed logistic regression with different nutrition assessment tools as the main predictors and age, sex, comorbidity, estimated glomerular filtration rate (eGFR), and hemoglobin as covariates. RESULTS: A total of 157 patients (93 men and 64 women; mean age 64 years; diabetes prevalence 38.9%) with CKD (eGFR 24.4 ± 13.4 mL/min/1.73 m2) were included. Overall, 29.3% of patients were frail. Patients with frailty were older and had a significantly higher fat tissue index and MIS but a significantly lower lean tissue index, eGFR, hemoglobin value, serum albumin value, handgrip strength value, and dietary protein intake. In multivariate logistic regression analyses, a higher body mass index category (odds ratio [OR], 1.54; 95% confidence interval [CI], 1.03-2.31), higher fat tissue index (OR, 1.15; 95% CI, 1.03-1.28), larger waist circumference (OR, 1.05; 95% CI, 1.01-1.09), reduced handgrip strength (OR, 2.70; 95% CI, 1.17-6.21), PEW defined by MIS ≥5 (OR, 3.49; 95% CI, 1.35-9.01), and dietary protein intake ≤0.8 g/kg/day (OR, 2.70; 95% CI, 1.18-6.19) were associated with higher odds of frailty. CONCLUSION: Frailty is associated with nutritional status in patients with CKD. A comprehensive nutrition assessment may allow the implementation of strategies to prevent or reduce frailty.

Anti-Inflammatory and Anti-Oxidative Effects of Polysaccharides Extracted from Unripe Carica papaya L. Fruit.

This study evaluated the antioxidative and anti-inflammatory activities of polysaccharides extracted from unripe Carica papaya L. (papaya) fruit. Three papaya polysaccharide (PP) fractions, namely PP-1, PP-2, and PP-3, with molecular weights of 2252, 2448, and 3741 kDa, containing abundant xylose, galacturonic acid, and mannose constituents, respectively, were obtained using diethylaminoethyl-Sepharose™ anion exchange chromatography. The antioxidant capacity of the PPs, hydroxyl radical scavenging assay, ferrous ion-chelating assay, and reducing power assay revealed that the PP-3 fraction had the highest antioxidant activity, with an EC50 (the concentration for 50% of the maximal effect) of 0.96 mg/mL, EC50 of 0.10 mg/mL, and Abs700 nm of 1.581 for the hydroxyl radical scavenging assay, ferrous ion-chelating assay, and reducing power assay, respectively. In addition, PP-3 significantly decreased reactive oxygen species production by 45.3%, NF-κB activation by 32.0%, and tumor necrosis factor-alpha and interleukin-6 generation by 33.5% and 34.4%, respectively, in H2O2-induced human epidermal keratinocytes. PP-3 exerts potent antioxidative and anti-inflammatory effects; thus, it is a potential biofunctional ingredient in the cosmetic industry.

Association of malnutrition with SARS-CoV-2 vaccine response in patients undergoing hemodialysis.

BACKGROUND & AIMS: Patients undergoing dialysis are less likely to develop immune responses to SARS-CoV-2 vaccine. Malnutrition is common in the dialysis population. However, whether malnutrition contributes to the impaired immunogenicity remains unknown. The aim of this study was to assess the association between nutritional status and SARS-CoV-2 vaccine response in patients receiving maintenance hemodialysis. METHODS: A total of 206 hemodialysis patients (mean age, 67 ± 13 years) without prior SARS-CoV-2 infection were examined for the primary outcome of seroconversion, defined as the detection of IgG antibodies (≥50 AU/mL) to the receptor-binding domain of the S1 spike protein of SARS-CoV-2 one month after a priming dose of ChAdOx1 nCoV-19, an adenovirus-vectored vaccine. Nutritional status was assessed by using the Controlling Nutritional Status (CONUT) score, an objective indicator of nutrition incorporating serum albumin, total cholesterol, and total lymphocyte count, as well as the subjective global assessment (SGA). RESULTS: Overall, 16.5% of patients were classified as malnourished, and 64.1% of patients were at risk for malnutrition based on the CONUT score. Anti-SARS-CoV-2 IgG were the highest in patients with normal nutrition. In multivariate logistic regression analyses adjusted for age, sex, comorbidities, and use of immunosuppressants, patients with malnutrition remained less likely to develop an antibody response than those with normal nutrition (odds ratio 0.23, 95% CI, 0.07-0.76). SGA was a significant predictor of anti-SARS-CoV-2 IgG seroconversion in univariate but not multivariate analyses. CONCLUSIONS: Malnutrition according to CONUT score is associated with impaired humoral responses to SARS-CoV-2 vaccination in patients undergoing hemodialysis. Our results highlight the importance of incorporating nutritional assessment into routine dialysis care to identify patients at risk for suboptimal immune responses after SARS-CoV-2 vaccination. Further research is needed to determine whether nutritional intervention can improve immune responses in these vulnerable patients.

Serum lipopolysaccharide-binding protein levels and cardiovascular events in hemodialysis patients: A prospective cohort study.

INTRODUCTION: Patients with end-stage kidney disease (ESKD) exhibit an elevated cardiovascular risk. Chronic inflammation is one of the main mechanisms of cardiovascular disease (CVD). Lipopolysaccharide has been proposed as a link between systemic inflammation and CVD. Herein, we evaluated whether lipopolysaccharide-binding protein (LBP), a surrogate marker of lipopolysaccharide and consequent inflammation, is associated with cardiovascular events in ESKD. METHODS: We performed a prospective cohort study of maintenance haemodialysis patients. Baseline serum LBP levels were categorized into tertiles and also modelled continuously for analyses. Cox regression methods were used to evaluate the association of serum LBP levels with cardiovascular events. RESULTS: A total of 360 haemodialysis patients were included in this analysis. During a median follow-up of 3.1 years, 90 (25.0%) patients had cardiovascular events. Patients in the upper tertile of serum LBP levels had a significantly greater risk of cardiovascular events [hazard ratio (HR) 4.87; 95% confidence intervals (CI), 2.12-11.15] than those in the lower tertile, independent of age, sex, hypertension, diabetes, CVD, dialysis vintage, body mass index, non-high-density lipoprotein cholesterol, albumin, phosphorus, high-sensitivity C-reactive protein, and interleukin-6. The association was consistent regardless of whether competing risk of death was accounted for (subdistribution HR 4.87; 95% CI, 1.96-12.11 for upper versus lower tertiles) or serum LBP was analysed as a continuous variable (HR 1.30; 95% CI, 1.02-1.66 per 1 SD increment). CONCLUSIONS: Serum LBP levels were independently associated with cardiovascular events in heomodialysis patients. LBP might serve as a novel biomarker for CVD in ESKD.

Aging is associated with slower renal progression in patients with chronic kidney disease.

Objectives: Chronic kidney disease (CKD) is prevalent among the elderly. However, little is known about how the clinical course of CKD vary with age. The purpose of this study was to examine the impact of aging on the risk of end-stage kidney disease (ESKD) in patients with moderate to advanced CKD. Materials and Methods: A total of 454 patients with stages 3-5 CKD were prospectively followed for a median of 5.1 years. The primary outcome was ESKD needing chronic dialysis therapy or preemptive kidney transplantation. The secondary outcome was a composite of ESKD or all-cause mortality. Results: The mean age of the patients was 65 ± 13 years. 65.4% were men, 44.9% had diabetes mellitus, and 22.7% had cardiovascular disease. Overall, 142 participants progressed to ESKD and 63 participants died. Compared with young patients (age <65 years, n = 205), elderly patients (age ≥65 years, n = 249) were associated with a significantly decreased risk of ESKD in Cox proportional hazards models adjusted for sex, smoking history, diabetes mellitus, cardiovascular disease, systolic blood pressure, estimated glomerular filtration rate, urine protein: Creatinine ratio, use of renin-angiotensin-aldosterone blocker, hemoglobin, phosphate, interleukin-6, body mass index, and N-terminal pro-brain natriuretic peptide (hazard ratio [HR]: 0.66; 95% confidence interval [CI]: 0.45, 0.96; P = 0.028). The results remained statistically significant when death as a competing risk was taken into account (subdistribution HR: 0.65; 95% CI: 0.45, 0.95, P = 0.026). Notably, elderly did not predict a higher risk for the composite outcome (HR: 0.94; 95% CI: 0.67, 1.32; P = 0.723). Conclusion: Elderly confers a decreased risk of ESKD in Taiwanese patients with moderate to advanced CKD. Our findings suggest that age is an important effect modifier for CKD progression.

Malnutrition is Associated with Increased Morbidity and Death in Dialysis Patients Undergoing Endovascular Therapy for Peripheral Artery Disease.

OBJECTIVE: Revascularisation for peripheral artery disease (PAD) is increasingly common in dialysis patients. Patients with PAD who have undergone revascularisation are at high risk of subsequent complications. Malnutrition is an important modifiable risk factor for dialysis patients, yet few data exist on the prognostic impact of malnutrition on post-procedure long term outcomes. The objective was to assess the prevalence and prognostic association of malnutrition using the Controlling Nutritional Status (CONUT) score in a prospective cohort of dialysis patients undergoing endovascular therapy (EVT) for PAD. METHODS: A total of 395 consecutive dialysis patients undergoing endovascular revascularisation for lower extremity PAD between 2005 and 2019 were examined for the primary outcome of all cause death. Secondary outcomes included major adverse limb events (MALEs), defined as acute limb ischaemia, major amputation, and clinically driven revascularisation; and major adverse cardiovascular events (MACEs). Nutritional status was assessed by CONUT score, a screening tool for malnutrition, incorporating albumin, cholesterol, and total lymphocyte count. RESULTS: According to the CONUT score, 40.8% of patients were moderately or severely malnourished. During a median follow up of 2.2 years, 218 (55.2%) patients died; 211 (53.4%) patients had MALEs, and MACEs occurred in 135 (34.2%) patients. Compared with normal nutritional status, severe malnutrition was associated with a significantly increased risk of all cause death (adjusted hazard ration [aHR] 4.83, 95% confidence interval [CI] 2.56 - 9.12) and MALEs (aHR 2.42, 95% CI 1.23 - 4.74) but not MACEs (aHR 1.81, 95% CI 0.74 - 4.40). Similar results were observed when the CONUT score was analysed as a continuous variable. CONCLUSION: Malnutrition is common in dialysis patients with PAD requiring endovascular therapy and is strongly associated with increased death and MALEs. Clinical trials are needed to evaluate whether nutritional interventions improve outcomes for dialysis patients after peripheral revascularisation.

Effect of Pholiota nameko Polysaccharides Inhibiting Methylglyoxal-Induced Glycation Damage In Vitro.

Advanced glycation end products (AGEs) can induce oxidative stress and inflammation. AGEs are major risk factors for the development of many aging-related diseases, such as cancer and diabetes. In this study, Pholiota nameko polysaccharides (PNPs) were prepared from water extract of P. nameko via graded alcohol precipitation (40%, 60%, and 80% v/v). We explored the in vitro antiglycation ability of the PNPs and inhibition of methylglyoxal (MG)-induced Hs68 cell damage. In a bovine serum albumin (BSA) glycation system, PNPs significantly inhibited the formation of Amadori products. Fluorescence spectrophotometry revealed that the PNPs trapped MG and reduced MG-induced changes in functional groups (carbonyl and ε-NH2) in the BSA. Pretreating Hs68 cells with PNPs enhanced the cell survival rate and protected against MG-induced cell damage. This was due to decreased intracellular ROS content. PNPs thus mitigate skin cell damage and oxidative stress resulting from glycation stress, making them a potential raw material for antiaging-related skincare products.

Loss of Function of von Hippel-Lindau Trigger Lipocalin 2-Dependent Inflammatory Responses in Cultured and Primary Renal Tubular Cells.

Previous studies have shown that mutations in the tumor suppressor gene von Hippel-Lindau (VHL) can result in the overproduction of reactive oxygen species (ROS) and chronic inflammation and are a significant predisposing factor for the development of clear-cell renal cell carcinoma (ccRCC). To study VHL's role in ccRCC formation, we previously developed a novel conditional knockout mouse model that mimicked the features of kidney inflammation and fibrosis that lead to cyst formation and hyperplasia. However, due to VHL's complex cellular functions, the mechanism of this phenomenon remains unclear. Here, we used the HK-2 cells and mouse primary renal tubule cells (mRTCs) carrying VHL mutations as models to study the effects and underlying molecular mechanisms of ROS accumulation. We also studied the role of lipocalin 2 (LCN2) in regulating macrophage recruitment by HK-2 cells. We measured the level of ROS in HK-2 cells in the presence or absence of LCN2 knockdown and found that the VHL mutation caused ROS overproduction, but an LCN2 knockdown could attenuate the process. VHL was also found to mediate the in vitro and in vivo expression and secretion of LCN2. Thus, VHL likely affects ROS production in an LCN2-dependent manner. Our findings also suggest that LCN2 sensitizes the inflammatory response of HK-2 cells and the chemotactic abilities of macrophage RAW264.7 cells. By demonstrating that the loss of function of von Hippel-Lindau triggers lipocalin 2-dependent inflammatory responses in cultured and primary renal tubular cells, our results offer novel insights into a potential therapeutic approach for interfering with the development of ccRCC.

Indoxyl Sulfate and Incident Peripheral Artery Disease in Hemodialysis Patients.

Peripheral artery disease (PAD) is highly prevalent among patients with chronic kidney disease (CKD) and portends a very poor prognosis. Indoxyl sulfate has been shown to induce atherothrombosis and impaired neovascularization in uremic mice. However, there is no clinical evidence regarding the role of indoxyl sulfate in PAD associated with CKD. We examined associations between indoxyl sulfate and incident symptomatic lower extremity PAD events as well as major adverse cardiovascular events (MACE) and all-cause mortality using Cox proportional hazards models in a prospective cohort of 200 hemodialysis patients free of PAD at baseline. Patients were considered as having PAD if they developed PAD symptoms confirmed by an ankle-brachial index with waveforms, duplex ultrasound or angiography, and/or major adverse limb events including revascularization and amputation. During a median follow-up of 6.5 years, 37 patients (18.5%) experienced incident symptomatic PAD. MACE occurred in 52 patients, and a total of 85 patients died. After adjusting for traditional risk factors for PAD, including age, current smoking, diabetes, and cardiovascular disease, indoxyl sulfate was significantly associated with the risk of PAD (hazard ratio (HR), 1.19 for every 10-µg/mL increase in indoxyl sulfate; 95% confidence interval (CI), 1.05-1.35). However, indoxyl sulfate was not associated with risk of MACE (HR, 1.00; 95% CI, 0.90-1.12) or death from any cause (HR, 0.98; 95% CI, 0.90-1.07). Indoxyl sulfate was associated with incident symptomatic PAD but not with MACE or all-cause mortality, suggesting that indoxyl sulfate toxicity may be unique to PAD among hemodialysis patients.

Methylation dependent gold adsorption behaviour identifies cancer derived extracellular vesicular DNA.

Extracellular vesicles (EV) play a major role in intercellular communication by transmitting cellular materials (e.g. protein, RNA) among distant cells. Recent evidence suggests that they could also contribute to carrying DNA which could inform on the mutational status of the parent tumour DNA. Thus, the fundamental analysis of evDNA could open a better understanding of tumour metastasis and provide new pathways for noninvasive detection and monitoring of cancer. To explore the potential of evDNA for diagnostics, the isolation of pure evDNA from body fluids free of cfDNA contamination is crucial. Herein, we use a liposome based model system to develop an improved evDNA isolation protocol free from cfDNA contamination and evaluate the methylation dependent physicochemical properties of evDNA to develop a simple test for detecting cancer evDNA. Using a highly sensitive multiplex microelectrode device, we demonstrate that serum-evDNA derived from cancer patients show different solution and surface based properties than normal evDNA due to their different methylation landscape (i.e. methylscape). This microdevice allows simultaneous analysis of multiple samples in a single platform from as low as 500 pg µL-1 of evDNA.

Characterization of Gut Microbiota Composition in Hemodialysis Patients With Normal Weight Obesity.

BACKGROUND: Normal weight obesity (NWO), defined by a normal body mass index (BMI) but increased body fat percentage (BF%), is associated with an increased risk of cardiovascular disease and mortality. NWO is characterized by inflammation and muscle wasting in chronic kidney disease (CKD), but the underlying mechanisms remain largely unknown. Gut microbiota has been implicated in the regulation of host metabolism and may play important roles in the development of NWO in CKD. METHODS: In this case-control study, we examined the gut microbial diversity and taxonomy in 96 hemodialysis patients with normal weight (BMI < 25 kg/m2 and BF% ≤ 25% for men or ≤ 35% for women; n = 32), NWO (BMI < 25 kg/m2 and BF% > 25% for men or > 35% for women; n = 32), and overweight/obesity (BMI ≥ 25 kg/m2; n = 32), matched for age, gender, and diabetes. BF% was measured using bioimpedance spectroscopy device. Gut microbiota was determined by 16S rRNA sequencing. RESULTS: We found that α-diversity was significantly different among the 3 adiposity phenotypes, with NWO being the least diverse. α-diversity was positively correlated with BMI, subjective global assessment score, and physical activity, but negatively correlated with interleukin-6 and tumor necrosis factor-α. Patients with or without NWO were distinguished with respect to principal coordinate analysis of ß-diversity. Notably, the relative abundance of butyrate-producing bacteria, such as Faecalibacterium prausnitzii and Coprococcus, was markedly reduced in patients with NWO. CONCLUSION: Our findings support associations between gut dysbiosis and a proinflammatory and catabolic state in hemodialysis patients with NWO.

Geriatric Nutritional Risk Index Is Associated with Unique Health Conditions and Clinical Outcomes in Chronic Kidney Disease Patients.

Malnutrition is prevalent in patients with chronic kidney disease (CKD). However, current nutrition screening tools are not specific to the CKD population. In the present study, we aimed to investigate whether the geriatric nutritional risk index (GNRI), a simple tool designed for assessing nutrition-related risks in the elderly population, is associated with unique aspects of CKD such as fluid status, residual renal function, proteinuria, and inflammation, and whether it predicts clinical outcomes. The GNRI was calculated by incorporating serum albumin and anthropometric measurements in 326 patients with nondialysis stage 3-5 CKD who were followed up from September 2011 to March 2017 for end-stage renal disease (ESRD) and the composite outcome of all-cause death and cardiovascular events. Patients were stratified into tertiles according to baseline GNRI levels. Patients in the lowest GNRI tertile were more likely to have significantly higher levels of overhydration, proteinuria, and serum inflammatory markers and tended to have lower lean body mass and estimated glomerular filtration rate when compared with patients in the middle and upper GNRI tertiles. In multivariate linear regression analyses, the GNRI was independently associated with overhydration, proteinuria, and interleukin-6. During a median follow-up of 4.9 years, 101 patients developed ESRD; 40 deaths, and 68 cardiovascular events occurred. Patients in the lowest GNRI tertile had significantly increased risks of ESRD (hazard ratio (HR): 3.15, 95% confidence interval (CI): 1.95-5.07, p < 0.001) and the composite outcome (HR: 1.79, 95% CI: 1.10-2.92, p = 0.019) in fully adjusted models (reference: middle and upper GNRI tertiles). The GNRI takes CKD-specific health conditions into account. In addition, CKD patients with lower GNRI scores had a significantly higher risk of adverse clinical outcomes. Our findings suggest that the GNRI is an appropriate tool for nutrition screening and a prognostic predictor among patients with nondialysis stage 3-5 CKD.

Interfacial nano-mixing in a miniaturised platform enables signal enhancement and in situ detection of cancer biomarkers.

Interfacial biosensing performs the detection of biomolecules at the bare-metal interface for disease diagnosis by comparing how biological species derived from patients and healthy individuals interact with bare metal surfaces. This technique retrieves clinicopathological information without complex surface functionalisation which is a major limitation of conventional techniques. However, it is still challenging to detect subtle molecular changes by interfacial biosensing, and the detection often requires prolonged sensing times due to the slow diffusion process of the biomolecules towards the sensor surface. Herein, we report on a novel strategy for interfacial biosensing which involves in situ electrochemical detection under the action of an electric field-induced nanoscopic flow at nanometre distance to the sensing surface. This nanomixing significantly increases target adsorption, reduces sensing time, and enables the detection of small molecular changes with enhanced sensitivity. Using a multiplex electrochemical microdevice that enables nanomixing and in situ label-free electrochemical detection, we demonstrate the detection of multiple cancer biomarkers on the same device. We present data for the detection of aberrant phosphorylation in the EGFR protein and hypermethylation in the EN1 gene region. Our method significantly shortens the assay period (from 40 min and 20 min to 3 minutes for protein and DNA, respectively), increases the sensitivity by up to two orders of magnitude, and improves detection specificity.

Factors Associated with Decreased Lean Tissue Index in Patients with Chronic Kidney Disease.

Muscle wasting is common and is associated with increased morbidity and mortality in patients with chronic kidney disease (CKD). However, factors associated with decreased muscle mass in CKD patients are seldom reported. We performed a cross-sectional study of 326 patients (age 65.8 ± 13.3 years) with stage 3-5 CKD who were not yet on dialysis. Muscle mass was determined using the Body Composition Monitor (BCM), a multifrequency bioimpedance spectroscopy device, and was expressed as the lean tissue index (LTI, lean tissue mass/height²). An LTI of less than 10% of the normal value (low LTI) indicates muscle wasting. Patients with low LTI (n = 40) tended to be diabetic, had significantly higher fat tissue index, urine protein creatinine ratio, and interleukin-6 and tumor necrosis factor-α levels, but had significantly lower serum albumin and hemoglobin levels compared with those with normal LTI. In multivariate linear regression analysis, age, sex, cardiovascular disease, and interleukin-6 were independently associated with LTI. Additionally, diabetes mellitus remained an independent predictor of muscle wasting according to low LTI by multivariate logistic regression analysis. We conclude that LTI has important clinical correlations. Determination of LTI may aid in clinical assessment by helping to identify muscle wasting among patients with stage 3-5 CKD.