The global burden of chronic kidney disease: estimates, variability and pitfalls. Nat Rev Nephrol. 2017;13:104-114. [PMID: 27941934 DOI: 10.1038/nrneph.2016.163]

Association of tea consumption with all-cause/cardiovascular disease mortality in the chronic kidney disease population: an assessment of participation in the national cohort

BACKGROUND

While there are numerous benefits to tea consumption, its long-term impact on patients with chronic kidney disease (CKD) remains unclear.

METHOD

Our analysis included 17,575 individuals with CKD from an initial 45,019 participants in the National Health and Nutrition Examination Survey (NHANES) (1999-2018). Individuals with extreme dietary habits, pregnancy, or non-CKD conditions were excluded. Key cohort demographics revealed a mean age of 62.3 years, with 52.1% female participants, and 57.3% identified as non-Hispanic White. A total of 5,835 deaths were recorded during follow-up, including 1,823 cardiovascular-related deaths. Cox and restricted cubic spline regression was used to examine the linear or nonlinear association of tea consumption with mortality. The substitution analysis explored the effects of replacing a specific type of tea with another type of tea. Subgroup analysis stratified by sex, age, body mass index (BMI), diabetes, cancer, cardiovascular disease (CVD), and urinary albumin. Sensitivity analysis was performed to ensure the reliability of our findings.

RESULTS

After adjusting for age, sex, race, education level, marital, annual household income, energy intake, total water intake, protein intake, carbohydrate intake, dietary fiber, sugar beverages, milk whole, total monounsaturated fatty acids, total polyunsaturated fatty acids, total saturated fatty acids, smoking, metabolic equivalent of task for physical activity level (MET-PA), BMI, diabetes, hypertension, urinary albumin, estimated glomerular filtration rate (eGFR), CVD, cancer, serum sodium, serum potassium, and serum phosphorus, setting the individuals without tea consumption record as reference. Consuming up to 4 cups of tea per day was significantly associated with lower all-cause mortality compared with that never drinking tea, among CKD patients at 1-2 stages [Hazard Ratio (HR) = 0.89; 95% Confidence Interval (CI) = 0.79, 0.99; p = 0.04], while the association between tea consumption and CVD mortality didn't reach statistical significance. Dose-response effect was observed, showing that consuming up to three to five cups of tea per day was associated with mitigated risks of all-cause mortality, particularly in early CKD stages (non-linear p > 0.05). A 1 cup per day higher intake of oxidized tea was associated with a 10% lower risk of all-cause mortality in CKD stage 1-2 [HR = 0.90; 95%CI = 0.82, 0.99; p = 0.03]. Replacing 1 cup of green tea with 1 cup of oxidized tea per day was associated with an 8% and 11% lower risk of all-cause mortality [HR = 0.92; 95%CI = 0.86, 0.98; p = 0.01] and CVD mortality [HR = 0.89; 95%CI = 0.80, 1.00; p < 0.05], respectively, in individuals with CKD stages 1-2.

CONCLUSION

Tea consumption showed protective effects on all-cause mortality in CKD population, with potential benefits observed in terms of both the cups quantity and types of tea consumed. These findings appeared to be more prominent among early stages CKD population.

Regulatory roles of noncanonical inflammasomes in kidney diseases

Inflammation is a body's immune defense against infection and injury. The inflammatory response has two main phases: the priming and triggering phases. The triggering phase involves the activation of inflammasomes, cytoplasmic platforms for initiating inflammation, and Inflammasomes are classified into two categories: canonical and noncanonical. Kidney disease, or renal disease, refers to damage or illness affecting the kidneys, leading to a progressive decline in their function. Although the roles of canonical inflammasomes in kidney diseases are well-documented, recent research highlights novel roles of noncanonical inflammasomes in managing various inflammatory conditions. In particular, emerging studies emphasize the regulatory functions of noncanonical inflammasomes in a range of kidney diseases. This review explores recent discoveries regarding the regulatory functions of noncanonical inflammasomes, including human caspase-4/5 and murine caspase-11, in the progression of kidney diseases. It also examines the potential of targeting these inflammasomes as a novel therapeutic approach.

Burdock Fructooligosaccharide Protects Against Diabetic Nephropathy in Mice by Regulating Nrf2 Signaling

Diabetic nephropathy (DN) is a common complication of diabetes mellitus, with oxidative stress playing a critical role in its development. Burdock fructooligosaccharide (BFO), a major compound in Burdock, exhibits antioxidative effects. However, its mechanisms of action and effects on diabetic nephropathy are not clear enough. This study aims to explore the mechanisms of BFO and its impact on streptozotocin-induced diabetic nephropathy in mice. Male C57BL/6J mice were randomly divided into normal control, DN, and BFO groups. Relevant serum biochemical parameters were detected using kits. Renal injury was evaluated through fluorescence microscopy, histopathology, and transmission electron microscopy. Nrf2/HO-1 signaling was analyzed via quantitative real-time PCR, western blotting, and immunohistochemistry. In DN mice, BFO significantly reduced fasting blood glucose, kidney index, urine protein, serum creatinine, blood urea nitrogen, total cholesterol, triglyceride, and low-density lipoprotein cholesterol, while significantly increasing high-density lipoprotein, SOD, and CAT levels. Additionally, BFO protected against streptozotocin-induced renal injury, restored podocyte function, increased both mRNA and protein expression of Nrf2, HO-1, and Bcl-2, and decreased those of Bax. In conclusion, BFO can be used to treat streptozotocin-induced renal injury in mice and is a promising candidate for diabetic nephropathy treatment.

Sex-specific association of co-exposures to melamine and phthalates in children with their early renal injury

Studies concerning the effect of co-exposure to melamine and phthalates on kidney function in children are rare. Thus, this study examines the above-mentioned relationship and their sex-different effect. Whether the exposure of the two chemicals from their mothers, when children were in the womb during the third trimester, affected renal injury markers in children afterwards is also examined. This study was from Taiwan Maternal and Infant Cohort Study cohort established in October 2012 to enroll third-trimester pregnant mothers up to May 2015. Their offspring were subsequently recruited between 2016 and 2020 as our study children. One-spot urine specimens were collected from both pregnant mothers (2012-2015) and study children (2016-2020) for the simultaneous measurement of melamine and 11 phthalate metabolites. Daily intakes of melamine and five phthalates, including DEHP (di-2-ethylhexylphthalate), DiBP (Dibutyl phthalate), DnBP (Di-n-butyl phthalate), BBzP (Butyl benzyl phthalate), and DEP (Diethyl phthalate), were estimated using a creatinine excretion-based model in both study children and their mothers. Two early markers of renal injury, microalbumin and N-acetyl-beta-D-glucosaminidas (NAG), were measured in urine samples of study children (2016-2020). A total of 552 eligible children were studied, with a mean age of 4 years. We found that boys in the highest quartile of estimated melamine intake (≥0.68 μg/kg/day) had significantly higher urine ACR levels and in the highest quartile of estimated phthalate intake of DEHP (≥5.36 μg/kg/day), DEP (≥0.89 μg/kg/day), and DiBP (≥1.19 μg/kg/day) had significantly higher urine NAG levels when compared to the combined three lowest quartile ones as comparison groups. No significant associations were found between their mothers' phthalates and melamine intake during the third trimester and urine ACR and NAG in children. We conclude that children (particularly boys) with high co-exposure of melamine and certain phthalate chemicals among children have increased early markers of kidney injury.

Engineered extracellular vesicles as imaging biomarkers and therapeutic applications for urological diseases

With the ever-increasing burden of urological diseases, the need for developing novel imaging biomarkers and therapeutics to manage these disorders has never been greater. Extracellular vesicles (EVs) are natural membranous nanoparticles and widely applied in both diagnostics and therapeutics for many diseases. A growing body of research has demonstrated that EVs can be engineered to enhance their efficiency, specificity, and safety. We systematically examine the strategies for achieving targeted delivery of EVs as well as the techniques for engineering them in this review, with a particular emphasis on cargo loading and transportation. Additionally, this review highlights and summarizes the wide range of imaging biomarkers and therapeutic applications of engineered EVs in the context of urological diseases, emphasizing the potential applications in urological malignancy and kidney diseases.

Physical activity is associated with renal function in middle-aged and elderly populations in China: first cross-sectional and longitudinal evidence from CHARLS

OBJECTIVE

Chronic kidney disease (CKD) has become a common health problem among middle-aged and elderly people in China. The aim of this study was to investigate the effects of physical activity on renal function in Chinese middle-aged and elderly people.

STUDY DESIGN

Nationwide cohort study.

METHODS

3599 participants in the 2011 China Health and Aging Longitudinal Study (CHARLS) were used in the cross-sectional study, with estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m2 as the endpoint event. 2309 participants in the 2015 CHARLS were used in the longitudinal study, with eGFR <60 ml/min/1.73 m2 or ≥25 % decrease in eGFR as the endpoint events. 2190 participants from the longitudinal study, after excluding those with baseline eGFR < 60 ml/min/1.73m2, were included in a sensitivity analysis to reassess the associations. Physical activity intensity was assessed by self-report. Associations between physical activity levels and renal function were analyzed using logistic regression.

RESULTS

In cross-sectional analyses, engaging in moderate (MPA) or vigorousphysical activity (VPA) for more than 300 min/week was associated with a significantly lower likelihood of renal endpoint events compared to physically inactive participants (OR = 0.39, 95 % CI: 0.30-0.51). After correction for clinical characteristics and blood test results, VPA and MPA >300 min/week remained independent protective factors for renal function. In the longitudinal cohort, VPA and MPA >300 min/w reduced the risk of renal endpoint events by 45 % (OR = 0.55, 95 % CI = 0.38-0.80). After correcting for clinical characteristics and blood test results, VPA and MPA >300min/w still reduced the risk of renal endpoint events by 37 % (OR = 0.63, 95 % CI = 0.43-0.92) and 39 % (OR = 0.61, 95 % CI: 0.42-0.89), respectively. Sensitivity analysis further confirmed the robustness of these findings, with VPA and MPA > 300 min/week consistently identified as independent protective factors.

CONCLUSIONS

Physical activity is associated with a reduced risk and delayed onset of renal insufficiency. The results of this study provide additional evidence for the renoprotective effects of exercise in non-CKD populations.

Matrix metalloproteinase-10 promotes kidney fibrosis by transactivating β-catenin signaling

Kidney fibrosis is characterized by excessive accumulation of extracellular matrix (ECM) and serves as a hallmark of chronic kidney disease (CKD). The turnover of ECM is controlled by a family of matrix metalloproteinases (MMPs), endopeptidases that play a crucial role in ECM remodeling and other cellular processes. In this study, we demonstrate that MMP-10 was upregulated in a variety of animal models of kidney fibrosis and human kidney biopsies from CKD patients. Bioinformatics analyses and experimental validation reveal that MMP-10 activated β-catenin in a Wnt-independent fashion. Knockdown of endogenous MMP-10 expression in vivo inhibited β-catenin activation and ameliorated kidney injury and fibrotic lesions, whereas over-expression of exogenous MMP-10 aggravated β-catenin activation and kidney fibrosis after injury. We found that MMP-10 cleaved and activated heparin-binding EGF-like growth factor (HB-EGF) via ectodomain shedding, leading to EGF receptor (EGFR) tyrosine phosphorylation and β-catenin transactivation via a cascade of events involving extracellular signal-regulated kinases and glycogen synthase kinase-3β. Consistently, treatment with erlotinib, a small-molecule EGFR inhibitor, effectively mitigated MMP-10-mediated kidney injury and fibrotic lesions in a dose-dependent fashion. Furthermore, β-catenin activation reciprocally upregulated the expression of MMP-10, thereby perpetuating kidney damage by forming a vicious cycle. Collectively, these results underscore that MMP-10 promotes kidney fibrosis through EGFR-mediated transactivating β-catenin in a Wnt-independent fashion. Our findings suggest that targeting MMP-10 could be a novel strategy for treatment of fibrotic CKD.

Impact of diabetes duration and hyperglycemia on the progression of diabetic kidney disease: Insights from the KNHANES 2019-2021

BACKGROUND

Diabetes is a significant risk factor for chronic kidney disease, and diabetic kidney disease (DKD) is prevalent among patients with diabetes. Previous studies have indicated that the duration of diabetes and poor glycemic control are associated with an increased risk of DKD, but data on how the duration and severity of hyperglycemia specifically relate to DKD progression are limited.

AIM

To investigate the relationship between diabetes duration and glycemic control, and DKD progression in South Korea.

METHODS

We included 2303 patients with diabetes using the 2019-2021 Korea National Health and Nutrition Examination Surveys data. DKD was defined as an estimated glomerular filtration rate (eGFR) < 60 mL/min per 1.73 m², urinary albumin-to-creatinine ratio ≥ 30 mg/g, or both. Diabetes duration and severity were classified into six categories each.

RESULTS

DKD prevalence was 25.5%. The DKD risk significantly increased in diabetes lasting 10-15 years or hemoglobin A1C (HbA1c) ≥ 8% compared to patients with newly diagnosed diabetes or HbA1c < 6.5%. Albuminuria developed with shorter diabetes duration and lower HbA1c than eGFR decline. The adjusted odds ratios for DKD were 3.77 [95% confidence interval (95%CI): 2.60-5.45] and 4.91 (95%CI: 2.80-8.63) in patients with diabetes lasting ≥ 20 years and HbA1c ≥ 10%, respectively, compared to those with new-onset diabetes and HgA1c < 6.5%.

CONCLUSION

Patients with diabetes lasting > 10 years or HbA1c > 8% had a higher risk of DKD, emphasizing the importance of early monitoring and management is crucial to prevent DKD progression.

Construction and validation of a nomogram for detecting chronic kidney disease in patients with nonalcoholic fatty liver disease: Insights from the NHANES database

BACKGROUND AND OBJECTIVES

Fatty liver disease is often associated with renal impairment in many patients. Early detection and prompt intervention are crucial for improving patient quality of life and reducing mortality rates. This study aimed to develop and validate a nomogram for detecting the risk of Chronic Kidney Disease (CKD) comorbidity in adults with Nonalcoholic Fatty Liver Disease (NAFLD) in the United States.

METHODS

From the NHANES (2017‒2020) database, the authors enrolled 2848 NAFLD participants, of whom 633 also had CKD. The authors employed the Least Absolute Shrinkage and Selection Operator (LASSO) regression and multivariate logistic regression to identify variables with predictive value. The overlapping features were selected to construct a predictive model, which was presented as a nomogram. The effectiveness of the nomogram was evaluated using Receiver Operating Characteristic (ROC) curves, calibration plots, and decision curve analysis.

RESULTS

Six indicators were included in the model: age, systolic blood pressure, serum albumin, high-sensitivity C-reactive protein, total cholesterol, and triglycerides. The area under the curve of the nomogram for predicting CKD in the training set was 0.772, with a 95 % Confidence Interval (95 % CI) of 0.746 to 0.797. In the validation set, the area under the curve was 0.722, with a 95 % CI of 0.680 to 0.763. The calibration curve analyses demonstrated that the prediction outcomes of the model aligned well with the actual outcomes, indicating good clinical applicability.

CONCLUSIONS

The nomogram demonstrated excellent performance and has the potential to serve as an auxiliary tool for detecting CKD in NAFLD patients.

A second act for spironolactone: cognitive benefits in renal dysfunction - a critical review

Renal dysfunction or Chronic kidney disease (CKD) are increasingly associated with cognitive deficit and memory impairment, suggesting a crucial kidney-brain axis. This review examines spironolactone's emerging role as a neuroprotective agent in the context of renal dysfunction-induced cognitive impairment. As a selective mineralocorticoid receptor (MR) antagonist, spironolactone demonstrates multifaceted protective mechanisms beyond its well established renoprotective effects. Evidences also suggests that spironolactone attenuates neuroinflammation, mitigates oxidative stress in brain, preserve blood-brain barrier (BBB) integrity and regulates hormonal imbalances associated with renal dysfunction. This review focuses on the reported beneficial effects of spironolactone in various neurodegenerative diseases (NDDs). These mechanisms collectively protect against the neurodegeneration in memory impairment induced by renal dysfunction. The dual action of spironolactone on both renal and cerebral tissues presents a novel therapeutic advantage in addressing this complex pathophysiology. This study elucidates multiple beneficial mechanisms by which spironolactone addresses cognitive impairment associated with renal dysfunction. Spironolactone enhances BBB protection and restores BBB integrity which is often compromised with renal dysfunction. It promotes neuroplasticity (allowing for improved neural adaptation and cognitive function), additionally mediates cerebral blood flow (CBF) ensuring adequate oxygen and nutrient delivery to brain. Spironolactone's anti-inflammatory effects by inhibiting the nuclear factor-kappa B (NF-κB) pathway and modulation of neuregulin1 (NRG1)/v-erb-b2 avian erythroblastic leukemia viral oncogene homolog 4 (ERBB4) signaling effectively reduce neuroinflammation that contributes to memory impairment. It also mitigates oxidative stress by targeting NADPH-oxidase (NOX), a major source of reactive oxygen species (ROS) in the central nervous system (CNS). Spironolactone also maintains hormonal balance, particularly regarding aldosterone levels, which become dysregulated in renal dysfunction and negatively impact brain function. These insights provide new possibilities for developing targeted therapies against renal dysfunction-induced memory impairment.

Frailty, genetic predisposition, and incident chronic kidney disease

Frailty is common among individuals with chronic kidney disease (CKD), whereas its impact on incident CKD risk remains unknown. This study aimed to prospectively evaluate the association between frailty and incident CKD risk, exploring the potential modification role of genetic risk factors (GRS). A cohort of 275,442 UK Biobank participants (mean age 55.3 ± 8.1 years, 43.4% male) without CKD were included. Physical frailty was defined by Fried Frailty phenotypes (FP) and Rockwood Frailty Index (FI). New-onset CKD was identified through hospital inpatient records and death register. GRS for CKD were calculated based on 27 single-nucleotide variants. Cox proportional hazards models and Fine-Gray competing risk models were applied to evaluate the hazard ratios (HRs) and 95% confidence intervals (CIs). During a median follow-up of 14.1 years, 5771 incident CKD cases were documented. Cox models indicated that prefrailty and frailty were associated with an increased CKD risk, with HRs (95% CI) of 1.17 (1.10-1.24) and 1.74 (1.58-1.91) for FP, and 1.33 (1.24-1.41) and 1.87 (1.72-2.04) for FI. These associations remained significant after adjusting for competing risks. Estimated population attributable fractions of frailty for CKD were 5.6% (FP) and 9.9% (FI). A positive non-linear relationship between FI and CKD incidence was observed in women (P non-linearity < 0.001). Associations were strengthened in women and those under 60 years of age (P for interaction < 0.05). Frailty significantly interacted with genetic susceptibility (P for interaction < 0.001), with the highest CKD risk observed in participants with high genetic risk and frailty (HR, 95% CI; FI: 2.28, 1.90-2.74; FP: 1.88, 1.52-2.33). Pre-frailty and frailty associated with incident CKD, with further modulation by GRS. These findings have important implications of frailty assessment and management in CKD prevention.

On the Path to a Sustainable Diet: Native Brazilian Fruits of the Caryocar spp. (Pequi and Piquiá) and Potential Health Benefits in Chronic Kidney Disease

The Caryocar genus includes Caryocar brasiliense, Caryocar villosum, and Caryocar coriaceum, known as pequi, piquiá, and piqui, respectively. They grow in the Cerrado and Amazonian biomes, significantly impacting the local economy. Caryocar spp. fruits are rich in carotenoids, lipids (oleic and palmitic acid), dietary fiber, zinc, magnesium, calcium, and polyphenols. These bioactive compounds potentially prevent and treat several non-communicable diseases, including chronic kidney disease (CKD). This narrative review discusses the potential advantages of Caryocar spp. including antioxidant and anti-inflammatory properties and the effects on renal insufficiency. The literature review shows that nutritional interventions are essential for CKD patients. Previous studies with Caryocar spp. demonstrate that cardiovascular protective effects due to their antioxidant and anti-inflammatory properties. Additionally, it emphasizes the importance of biodiversity in human health promotion. In conclusion, this review offers a theoretical foundation for Caryocar spp. as a potential nutraceutical in the context of CKD and highlights its value as a key component of a sustainable diet.

Development of a Long-Acting Interleukin-11 Antagonist for the Treatment of Renal Fibrosis

Renal fibrosis, a key progression of chronic kidney disease (CKD), remains a major challenge in nephrology, with no FDA-approved drugs specifically targeting this condition. Interleukin-11 (IL-11) has emerged as a potential therapeutic target for renal fibrosis. In this study, we identified the antifibrotic effects of a recombinant human IL-11 analogue, IL-11-6M, in a mouse model of unilateral ureteral obstruction (UUO). We generated additional IL-11-6M variants via an optimized Escherichia coli expression system, with one variant (D46C) exhibiting comparable efficacy. Further modified through cysteine-specific PEGylation, analogue 13 demonstrated similar potency to IL-11-6M with an IC50 value of 61.5 ± 26.2 nM and maintained strong binding affinity to IL-11Rα (KD = 3.0 nM). Notably, analogue 13 exhibited a prolonged half-life and showed significant therapeutic effects in the UUO-induced renal fibrosis model. These findings suggest analogue 13 should be a promising candidate for the treatment of renal fibrosis.

Osteoarthritis is a risk factor for renal function injury based on the National Health and Nutrition Examination Survey and Mendelian Randomized study

This study aims to investigate the association and causality between osteoarthritis (OA) and chronic kidney disease (CKD) using data from the National Health and Nutrition Examination Survey (NHANES) and Mendelian Randomization (MR) analysis. Participants with OA, urinary albumin, urinary creatinine, urinary albumin-to-creatinine ratio (UACR), blood creatinine, and estimated glomerular filtration rate (eGFR) were selected from NHANES. CKD was calculated using the CKD-EPI equation, and logistic regression assessed by the OA-CKD association. A two-sample MR analysis was conducted using Genome-wide association studies (GWAS) data for OA, hip OA (HOA), knee OA (KOA), acute renal failure (ARF), chronic renal failure (CRF), cystatin C, serum creatinine (eGFRcrea), and microalbuminuria. The inverse variance weighted (IVW) method was used, with heterogeneity, sensitivity, and pleiotropy assessments. The cross-sectional analysis showed a significant positive association between OA and CKD [unadjusted OR: 2.398 (95% CI: 2.176-2.643), p < 0.001], which persisted after adjustment for demographic factors, socioeconomic status, lifestyle factors, and medical history [adjusted OR: 1.161 (95% CI: 1.029-1.310), p = 0.015]. The MR analysis revealed no significant causal relationship between overall OA and renal function markers but found a significant genetic association between HOA and cystatin C [IVW p = 0.0014, OR = 1.02, 95% CI: 1.01-1.03], and between KOA and cystatin C [IVW p < 0.0001, OR = 1.06, 95% CI: 1.04-1.08]. Our study indicates that HOA and KOA are risk factors for renal function injury, providing new insights for clinical OA management.

Improving polygenic risk prediction of renal function by removing biomarker-specific effects

Biomarkers are frequently used in clinical practice; however, it is essential to consider the genetics that may independently impact their baseline levels in-turn impacting interpretation of results. For example, estimated glomerular filtration rate (eGFR) equations are based on two biomarkers, cystatin C and creatinine, and widely employed in clinical practice. In this work we demonstrate how genetics of the underlying biomarkers impact measurement variability and may explain some of the discrepancies among eGFR equations. To do this we used shared genetic-architecture to identify "shared" (renal-specific) and "biomarker-specific" regions of the genome. The shared polygenic risk score (PRS) explained 60% more of the variability in the most-common creatinine-derived eGFR estimates than either the biomarker-specific PRS or a PRS including all regions. Our findings highlight the necessity of considering biomarker-specific genetics when constructing PRS for eGFR and other biomarker-derived clinical risk estimates.

Sarcopenic obesity and the risk of atrial fibrillation in non-diabetic older adults: A prospective cohort study

BACKGROUND

Evidence of an association between sarcopenic obesity (SO) and the risk of long-term atrial fibrillation (AF) is lacking, and the underlying involvement of insulin resistance (IR) and inflammation is not clear.

METHODS

This community-based prospective cohort study evaluated sarcopenia, obesity, and baseline clinical characteristics in 4321 non-diabetic older adults between 2007 and 2011. Sarcopenia was identified using skeletal muscle mass/body weight (SMM/BW), appendicular lean mass (ALM)/BW, and handgrip strength (HGS), and obesity was identified by fat mass (FM)/BW. The association of sarcopenia and obesity with AF risk was determined by Kaplan-Meier analysis and a Cox proportional hazards model. Interaction analysis, a restricted cubic splines model, mediation analysis, and a Fine-Gray competing-risk model were also used.

RESULTS

Over an average of 10.9 years of follow-up, 546 (11.98 per 1000 person-years) participants developed AF. Low SMM/BW, low ALM/BW, low HGS, high FM/BW, sarcopenia and obesity, were significantly associated with an increased AF risk. There was a significant synergistic relationship between sarcopenia and obesity in the increased AF risk [hazard ratio (HR): 2.029, 95 % confidence interval (CI): 1.639-2.512]. Compared with participants without sarcopenia and obesity, AF risk was the highest in those with SO (HR: 2.669, 95 % CI: 2.110-3.377], followed by sarcopenia alone (HR: 1.980, 95%CI: 1.453-2.699) and obesity (HR: 1.839, 95%CI: 1.475-2.292). Mediation analysis found that estimated glucose disposal rate (a surrogate marker of IR), high-sensitivity C-reactive protein, and galectin-3 were mediating factors in the increased AF risk caused by SO, accounting for 34.87 %, 27.56 %, and 21.05 % of the total effect, respectively.

CONCLUSIONS

SO significantly increased AF risk in these non-diabetic older individuals. Sarcopenia and obesity not only acted alone but also exhibit had a synergistic relationship to increase AF risk. IR and inflammation mediated the increased AF risk associated with SO.

Identifying a cohort of hospitalized chronic kidney disease patients using electronic health records: lessons learnt and implications for future research and clinical practice guidelines

Background

Safe medication prescribing for hospitalized chronic kidney disease (CKD) patients is challenging. Leveraging electronic health records (EHRs) offers potential for decision support. A first step is to capture the CKD cohort through so called electronic phenotypes (e-phenotypes). However, available e-phenotypes, defined by logical rules applied to EHR data, lack consensus and are often inconsistently aligned with the Kidney Disease - Improving Global Outcomes (KDIGO) guideline for CKD (KDIGO-CKD). Therefore, local analyses and formalization efforts are essential to derive logical rules for CKD cohort selection.

Methods

We analyzed routinely collected EHR data from adults hospitalized at Amsterdam University Medical Centre (2018-23). Six logical rules were investigated: four derived from KDIGO-CKD (reduced glomerular filtration rate, albuminuria, kidney replacement therapy, and other markers of kidney damage) and two from published studies (diagnosis codes and medications).

Results

The study included 108 854 hospitalized patients. Extensive efforts were needed to formalize the clinical CKD definition from KDIGO-CKD and adapt it to EHR data, including selecting appropriate CKD diagnosis codes, medications, and computable criteria. Pooling six logical rules resulted in identifying 17 805 hospitalized CKD patients (16.4%), showcasing varying CKD patient counts per rule (with proportions ranging from 2.1% to 8.4%). Nonetheless, baseline characteristics across cohorts were comparable. Over one-third of patients identified by decreased eGFR or albuminuria/proteinuria measurements lacked a corresponding diagnosis code.

Conclusions

Deriving and formalizing six logical rules required close collaboration between nephrologists, EHR data experts, and medical informaticians. Our study provides groundwork towards a computer-interpretable CKD definition to standardize cohort capture in EHR-based studies.

Dietary index for gut microbiota, a novel protective factor for the prevalence of chronic kidney diseases in the adults: insight from NHANES 2007-2018

Introduction

This study explore the association between the dietary index for gut microbiota (DI-GM) and the prevalence of chronic kidney disease (CKD).

Method

A cross-sectional study of participants aged ≥20 years using the data drawn from NHANES (2007-2018). DI-GM is comprised 14 dietary components (10 beneficial and 4 unfavorable). CKD diagnosis based on urine albumin-to-creatinine ratio (uACR) and estimated glomerular filtration rate (eGFR). Logistic regression models were employed to evaluate the relationship between DI-GM and CKD while controlling for various covariates. Additionally, a spline smooth analysis was performed. Subgroup and interaction analyses were conducted to investigate whether any factors modified this relationship.

Results

A total of 28,843 participants were eligible for the study, of whom 5,461 were diagnosed with CKD, while 23,382 were not. Patients with CKD exhibited significantly lower DI-GM scores compared to healthy individuals. A negative association between DI-GM and the prevalence of CKD was observed across all models, with the relationship being more pronounced in individuals with DI-GM scores greater than 5 compared to those with scores ≤3. Beneficial components, such as dietary fiber, whole grains, and coffee, were identified as protective factors. Moreover, sex make an effect on this relationship, with stronger effects noted in women.

Conclusion

Higher DI-GM scores correlate with reduced CKD prevalence, and the effect appears to be more pronounced in women than in men. These findings suggest that enhancing gut health through diet may serve as a viable strategy for the prevention and management of CKD, with particular attention to sex-based differences in prevention.

Morroniside Ameliorates High-Fat and High-Fructose-Driven Chronic Kidney Disease by Motivating AMPK-TFEB Signal Activation to Accelerate Lipophagy and Inhibiting Inflammatory Response

Studies have substantiated that dietary-fat- and fructose-overconsumption-caused lipid metabolism disorders can trigger renal lipotoxicity to drive the progression of chronic kidney disease (CKD). This study was conducted to evaluate the efficacy of morroniside, a natural active substance extracted from the fruit of Cornus officinalis, in inhibiting the progression of CKD in high-fat and high-fructose-fed mice. Our results showed histological changes such as fatty degeneration of renal tubular cells, tubular dilatation, glomerular fibrosis, and abnormal renal function in the kidneys of high-fat- and high-fructose-fed mice, which was significantly improved after morroniside treatment. Mechanistically, morroniside maintained renal lipid metabolism homeostasis and inhibited NLRP3 inflammatory vesicle activation by activating AMPKα to promote TFEB nuclear translocation-mediated lipophagy. Consistent results were observed in palmitic acid-induced HK-2 cells. Notably, silencing AMPKα or TFEB both reversed the effects of morroniside in promoting lipophagy and inhibiting the activation of inflammatory responses in vivo and in vitro. Therefore, our study provides compelling evidence that morroniside delays CKD progression by promoting AMPK/TFEB-mediated lipophagy and inhibiting NLRP3 inflammasome activation, suggesting that dietary supplementation with morroniside and morroniside-rich foods (such as Cornus officinalis) might be an effective strategy for the prevention of CKD.

Association of body round index with chronic kidney disease: a population-based cross-sectional study from NHANES 1999-2018

BACKGROUND

Complex nexuses between obesity and chronic kidney disease (CKD) have been reported. Nevertheless, the link between the body roundness index (BRI), an indicator utilized to measure body fat distribution, and CKD risk has been unexplored.

METHODS

We utilized publicly available data from ten survey cycles (1999-2018) of the National Health and Nutrition Examination Survey (NHANES) in the United States. We examined the association between BRI and CKD risk using multivariable logistic regression, subgroup analysis, interaction tests, and smooth curve fitting.

RESULTS

The study ultimately involved 41,953 participants, 3,123 (7.44%) of whom had CKD. Multivariable logistic regression, adjusted for covariates, identified high BRI levels in quartile 4 as a risk factor for CKD (OR = 1.30, 95% CI 1.12-1.50, P = 0.0005). This association remained consistent across subgroups (P for interaction > 0.05). Smoothed curve fitting exhibited a roughly linear positive correlation between BRI and CKD.

CONCLUSION

According to our study, BRI was related to CKD in a roughly linear way, suggesting a novel indicator for improving prevention and treatment for the CKD population. Nevertheless, additional research is needed to identify the association.

Oxidative stress and NRF2 signaling in kidney injury

Oxidative stress plays a crucial role in the pathogenesis of acute kidney injury (AKI), chronic kidney disease (CKD), and the AKI-to-CKD transition. This review examines the intricate relationship between oxidative stress and kidney pathophysiology, emphasizing the potential therapeutic role of nuclear factor erythroid 2-related factor 2 (NRF2), a master regulator of cellular redox homeostasis. In diverse AKI and CKD models, diminished NRF2 activity exacerbates oxidative stress, whereas genetic and pharmacological NRF2 activation alleviates kidney damage induced by nephrotoxic agents, ischemia-reperfusion injury, fibrotic stimuli, and diabetic nephropathy. The renoprotective effects of NRF2 extend beyond antioxidant defense, encompassing its anti-inflammatory and anti-fibrotic properties. The significance of NRF2 in renal fibrosis is further underscored by its interaction with the transforming growth factor-β signaling cascade. Clinical trials using bardoxolone methyl, a potent NRF2 activator, have yielded both encouraging and challenging outcomes, illustrating the intricacy of modulating NRF2 in human subjects. In summary, this overview suggests the therapeutic potential of targeting NRF2 in kidney disorders and highlights the necessity for continued research to refine treatment approaches.

Development and evaluation of a kidney health questionnaire and estimates of chronic kidney disease prevalence in the Cooperative Health Research in South Tyrol (CHRIS) study

BACKGROUND

Kidney diseases are a public health burden but are poorly investigated in the general population. In light of inadequate survey tools, we developed a novel questionnaire for use in population-based studies, to retrospectively assess kidney diseases.

METHODS

The questionnaire covered general kidney diseases, reduced kidney function, and renal surgeries. It was administered between 2011 and 2018 to 11,684 participants (median age = 45 years) of the Cooperative Health Research in South Tyrol (CHRIS) study. Fasting estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio (UACR) were measured. By factor analysis we contextualized the questionnaire content with respect to the biochemical measurements. We estimated overall and sex-stratified prevalence of kidney diseases, including possible CKD, calibrating them to the general target population via relative sampling weights.

RESULTS

Population-representative prevalence of glomerulonephritis, pyelonephritis, and congenital kidney diseases was 1.0%, 3.0%, and 0.2%, respectively, with corresponding odds ratios for females versus males of 1.4 (95% confidence interval: 1.0, 2.0), 8.7 (6.2, 12.3), and 0.7 (0.3, 1.6), respectively. Prevalence of kidney dysfunction (eGFR < 60 mL/min/1.73 m2 or UACR > 30 mg/g) was 8.59%, while prevalence of self-reported CKD was 0.69%, indicating 95.3% of lack of disease awareness, with a similar figure in people with diabetes or hypertension. Overall, 15.76% of the population was affected by a kidney disease of any kind.

CONCLUSION

In the Val Venosta/Vinschgau alpine district, CKD prevalence aligned with Western European estimates. Kidney health questionnaire implementation in population studies is feasible and valuable to assess CKD awareness, which we found to be dramatically low.

Use of Aspirin and Initial Cardiovascular and Bleeding Risk in Patients with Chronic Kidney Disease

Key Points

The association between aspirin use and risk of the first cardiovascular event was NS in patients with CKD. Compared with nonusers, aspirin users had an increased risk of significant bleeding events. Aspirin prescription for the primary prevention of cardiovascular disease in patients with CKD needs careful consideration.

Background

Despite the high cardiovascular risk in patients with CKD, the role of aspirin in primary prevention remains unclear. This study aimed to investigate the association between aspirin initiation in adults with CKD without prior cardiovascular disease (CVD) and the first cardiovascular and bleeding events using Korean nationwide cohort data.

Methods

Among individuals aged 40–79 years with an eGFR between 15 and 59 ml/min per 1.73 m2 who underwent routine health examinations between 2011 and 2016, 15,861 individuals who were newly prescribed aspirin at a dose of 100 mg/d were matched with 79,305 aspirin non-users by propensity score matching. The primary efficacy outcome was a composite of nonfatal atherosclerotic CVD or cardiovascular death. The primary safety outcome was hospitalization due to intracranial or gastrointestinal bleeding.

Results

During a mean follow-up of 6.9±2.9 years, the incidence rates for the primary efficacy outcome in aspirin users and nonusers were 8.0 and 9.0 per 1000 person-years, respectively. Aspirin therapy initiation was not associated with the primary efficacy outcome (hazard ratio, 0.93; 95% confidence intervals, 0.86 to 1.04). However, the primary safety outcome of major bleeding was more frequent in aspirin users than in nonusers (6.7 versus 4.7 per 1000 person-years). The hazard ratio for this outcome in aspirin users versus nonusers was 1.45 (95% confidence intervals, 1.32 to 1.59).

Conclusions

No association was observed between aspirin use and the risk of nonfatal atherosclerotic CVD or cardiovascular death in patients with CKD stages G3 and G4 without prior CVD. Aspirin use was associated with higher risk of major bleeding.

Associations of metabolic variabilities and cardiovascular outcomes according to estimated glomerular filtration rate in chronic kidney disease: a nationwide observational cohort study

BACKGROUND

The impact of baseline estimated glomerular filtration rate (eGFR) on the risk of adverse outcomes according to metabolic parameter variabilities in chronic kidney disease has rarely been investigated.

METHODS

We conducted a retrospective nationwide cohort study using the National Health Insurance System data in Korea from 2007 to 2013 to identify individuals with three or more health screenings. The metabolic components variability was defined as intraindividual variability between measurements using the variability independent of the mean. The metabolic variability score was defined as the total number of high-variability metabolic components. Multivariable-adjusted Cox regression analysis was conducted to evaluate the risks of all-cause mortality, myocardial infarction, and ischemic stroke.

RESULTS

During a mean follow-up of 6.0 ± 0.7 years, 223,531 deaths, 107,140 myocardial infarctions, and 116,182 ischemic strokes were identified in 9,971,562 patients. Low eGFR categories and higher metabolic variability scores were associated with a higher risk of adverse outcomes. The degree of association between metabolic variability and adverse outcomes was significantly larger in those with low eGFR categories than in those with preserved eGFR (p for interaction < 0.001). Representatively, those with high metabolic variability in the eGFR of <15 mL/min/1.73 m2 group showed a prominently higher risk for all-cause mortality (adjusted hazard ratio [aHR], 5.28; 95% confidence interval [CI], 4.02-6.94) when the degree was compared to the findings in those with preserved (eGFR of ≥60 mL/min/1.73 m2) kidney function (aHR, 2.55; 95% CI, 2.41-2.69).

CONCLUSION

The degree of adverse association between metabolic variability and poor prognosis is accentuated in patients with impaired kidney function.

Ubiquitin-specific peptidase 10 promotes renal interstitial fibrosis progression through deubiquitinating and stabilizing P53 protein

Renal interstitial fibrosis is the main factor determining chronic kidney disease (CKD) progression, and renal tubular epithelial cells are the key drivers of this pathological process. Herein, we revealed significantly increased ubiquitin-specific peptidase 10 (USP10) expression in the kidney tissues of both patients with CKD and mice induced by unilateral ureteral obstruction, as well as in transforming growth factor-beta 1 (TGFβ1)-induced renal tubular epithelial cells. In vivo, treatment with the USP10 small molecule inhibitor Spautin-1, which inhibits its deubiquitinating activity, weakened renal interstitial fibrosis progression and alleviated the subsequent inflammatory response and oxidative stress in male mice. In vitro, knocking down USP10 or inhibiting its deubiquitinating activity through Spautin-1 significantly reduced fibronectin expression and ameliorated TGFβ1-induced renal tubular epithelial cell dedifferentiation. Additionally, our results revealed that USP10 directly binds to P53 and removes the K48-linked polyubiquitin chains from P53, thereby affecting its ubiquitination, stability, and nuclear translocation, which subsequently leads to the upregulation of P21 and promotes fibrotic gene expression in injured renal tubular epithelial cells, ultimately exacerbating renal interstitial fibrosis. In conclusion, USP10 is inhibited through the P53 signaling pathway to alleviate the progression of renal interstitial fibrosis and serve as a potential target for treating CKD.

Bioinformatics analysis of the expression of potential common genes and immune-related genes between atrial fibrillation and chronic kidney disease

Research objective

This study is based on bioinformatics analysis to explore the co-expressed differentially expressed genes (DEGs) between atrial fibrillation (AF) and chronic kidney disease (CKD), identify the biomarkers for the occurrence and development of the two diseases, investigate the potential connections between AF and CKD, and explore the associations with immune cells.

Methods

We downloaded Two AF gene chip datasets (GSE79768, GSE14975) and two CKD gene chip datasets (GSE37171, GSE120683) from the GEO database. After pre-processing and standardizing the datasets, two DEGs datasets were obtained. The DEGs were screened using R language, and the intersection was taken through Venn diagrams to obtain the co-expressed DEGs of AF and CKD. To obtain the signal pathways where the co-expressed DEGs were significantly enriched, GO/KEGG enrichment analyses were used to analysis the co-expressed DEGs. The Cytoscape software was used to further construct a PPI network and screen key characteristic genes, and the top 15 co-expressed DEGs were screened through the topological algorithm MCC. To further screen key characteristic genes, two machine-learning algorithms, LASSO regression and RF algorithm, were performed to screen key characteristic genes for the two disease datasets respectively to determine the diagnostic values of the characteristic genes in the two diseases. The GeneMANIA online database and Networkanalyst platform were used to construct gene-gene and TFs-gene interaction network diagrams respectively to predict gene functions and find key transcription factors. Finally, the correlation between key genes and immune cell subtypes was performed by Spearman analysis.

Research results

A total of 425 DEGs were screened out from the AF dataset, and 4,128 DEGs were screened out from the CKD dataset. After taking the intersection of the two, 82 co-expressed DEGs were obtained. The results of GO enrichment analysis of DEGs showed that the genes were mainly enriched in biological processes such as secretory granule lumen, blood microparticles, complement binding, and antigen binding. KEGG functional enrichment analysis indicated that the genes were mainly enriched in pathways such as the complement coagulation cascade, systemic lupus erythematosus, and Staphylococcus aureus infection. The top 15 DEGs were obtained through the MCC topological algorithm of Cytoscape software. Subsequently, based on LASSO regression and RF algorithm, the key characteristic genes of the 15 co-expressed DEGs of AF and CKD were further screened, and by taking the intersection through Venn diagrams, five key characteristic genes were finally obtained: PPBP, CXCL1, LRRK2, RGS18, RSAD2. ROC curves were constructed to calculate the area under the curve to verify the diagnostic efficacy of the key characteristic genes for diseases. The results showed that RSAD2 had the highest diagnostic value for AF, and the diagnostic values of PPBP, CXCL1, and RSAD2 for CKD were all at a relatively strong verification level. Based on AUC >0.7, co-expressed key genes with strong diagnostic efficacy were obtained: PPBP, CXCL1, RSAD2. The results of the GeneMANIA online database showed that the two biomarkers, BBPB and CXCL1, mainly had functional interactions with cytokine activity, chemokine receptor activity, cell response to chemokines, neutrophil migration, response to chemokines, granulocyte chemotaxis, and granulocyte migration. The TFs-gene regulatory network identified FOXC1, FOXL1, and GATA2 as the main transcription factors of the key characteristic genes. Finally, through immune infiltration analysis, the results indicated that there were various immune cell infiltrations in the development processes of AF and CKD.

Research conclusion

PPBP, CXCL1, and RSAD2 are key genes closely related to the occurrence and development processes between AF and CKD. Among them, the CXCLs/CXCR signaling pathway play a crucial role in the development processes of the two diseases likely. In addition, FOXC1, FOXL1, and GATA2 may be potential therapeutic targets for AF combined with CKD, and the development of the diseases is closely related to immune cell infiltration.

Liquid chromatography coupled with high resolution mass spectrometry reveals the inhibitory effects of Huangkuisiwu formula on biosynthesis of protein-binding uremic toxins in rats with chronic kidney disease

Chronic kidney disease (CKD) is recognized as a common disorder worldwide. Protein-binding uremic toxins that cannot be efficiently removed by extracorporeal renal replacement therapies, such as indoxyl sulfate (IS) and p-cresyl sulfate (PCS), are associated with high risks of cardiovascular complications and high mortality in CKD population. This study aimed to explore the therapeutical effects of Huangkuisiwu formula (HKSWF) on CKD rats. Moreover, the underlying mechanisms of HKSWF to inhibit the biosynthesis of IS and PCS were studied. Untargeted metabolomics based on UHPLC-QTOF/MS was conducted to analyze the alterations of endogenous metabolites in plasma. Levels of IS and PCS in plasma and peripheral tissues, as well as levels of amino acids in colonic contents were analyzed by UHPLC-TQ/MS. Levels of indole and p-cresol, the precursors of IS and PCS, in feces and colonic contents were quantified by HPLC-FLD. mRNA and protein expression of sulfotransferase 1 a1 (SULT1A1) were determined by qPCR and Western blotting, respectively. The ability of colonic microbiota to metabolize amino acids into precursors, as well as the activity of sulfotransferase to catalyze precursors into uremic toxins were evaluated by detecting corresponding products from specific substrates. 16S rRNA sequencing were conducted to analyze the profile of gut microbiota. The results showed that HKSWF significantly alleviated the structural and functional impairment of kidney, as well as improved the global metabolic disorders in CKD rats. IS and PCS were identified as the key differential metabolites that contributed to the effects of HKSWF. HKSWF significantly reduced the levels of IS and PCS in plasma, kidney, liver and heart of CKD rats. HKSWF showed no significant effects on the expression of SULT1A1 or the activity of sulfotransferase. HKSWF significantly decreased the levels of indole and p-cresol in the colonic contents and feces of CKD rats, by inhibiting the ability of colonic microbiota to metabolize tryptophan and tyrosine into indole and p-cresol. Alterations in the profile of amino acids and gut microbiota in CKD rats were significantly improved by HKSWF treatment. Conclusively, HKSWF inhibited gut-microbiota mediated biosynthesis of indole and p-cresol, to alleviate the accumulation of IS and PCS in CKD rats.

Sarcopenia and Insulin Resistance Collective Effect on Atrial Fibrillation Risk: A Non-Diabetic Elderly Cohort Study

BACKGROUND

Appendicular skeletal muscle mass index (ASMI), a crucial indicator of sarcopenia and estimated glucose disposal rate (eGDR), a surrogate marker of insulin resistance (IR), are associated with the risk of cardiovascular diseases. However, it remains unclear whether the collective effects, including the impact of the temporal progression of ASMI and eGDR, affect atrial fibrillation (AF) risk. This study aims to elucidate the association between the collective effects of ASMI and eGDR and AF risk in the non-diabetic older population.

METHODS

A total of 8060 non-diabetic older individuals from a community-based cohort study were used to prospectively analyse the association between the collective effects of baseline ASMI and eGDR and AF risk. Among them, 7651 were eligible and used for dual-trajectory analysis of the association between dual trajectory of ASMI and eGDR and AF risk. The temporal development of ASMI and eGDR over time was determined using a dual-trajectory model. Statistical analyses involved restricted cubic splines and Fine-Gray competing risk models, adjusting for potential confounders.

RESULTS

In the prospective analysis, the hazard ratio (HR) of AF was 1.762 (95% confidence interval [CI]: 1.528-2.032) in the low ASMI group compared to the normal ASMI group in total participants. Restricted cubic splines analysis demonstrated L-shaped associations between AF risk and ASMI and eGDR, with inflection points at 7.23 kg/m2 and 7.85 mg/kg/min, respectively. Low ASMI and moderate and low eGDR exhibited a significant interplay for increasing AF risk (HR: 1.290 and 1.666, 95% CI: 1.136-1.464 and 1.492-1.861, respectively, padj. < 0.001). One-SD increment ASMI and eGDR synergistically reduced AF risk (HR: 0.896, 95% CI: 0.839-0.957, padj. < 0.001). In the dual-trajectory analysis for total participants, five distinct dual trajectories of ASMI and eGDR were identified. Group 4, characterized by moderate-stable ASMI and moderate-stable eGDR, exhibited the lowest incidence of AF (7.03 per 1000 person-years) and was used as a reference for further analyses. Group 1, characterized by high-decrease ASMI and high-decrease eGDR, had the highest AF risk (HR: 2.255, 95% CI: 1.769-2.876, padj. < 0.001), followed by Group 5, with high-decrease ASMI and low-stable eGDR (HR: 1.893, 95% CI: 1.491-2.403, padj. < 0.001) when compared to Group 4 after adjustment for potential confounders including baseline ASMI and eGDR.

CONCLUSIONS

The collective effects of ASMI and eGDR are significantly associated with AF risk in the non-diabetic older population. Collective management of skeletal muscle mass and IR might be a useful and effective management strategy for preventing and controlling AF.

Investigating the role of the metabolic score for visceral Fat in assessing the prevalence of chronic kidney disease from the NHANES 1999-2018

This study investigates the association between the Metabolic Score for Visceral Fat (METS-VF) and chronic kidney disease (CKD), assessing METS-VF as a potential predictor of CKD risk. Utilizing data from the 1999-2018 National Health and Nutrition Examination Survey (NHANES), this cross-sectional study included 24,387 adult participants. Multivariable logistic regression, restricted cubic spline models, and threshold effect analyses were employed to explore the relationship. The results revealed a significant positive association, with multivariable logistic regression showing that each unit increase in METS-VF was associated with an 86% higher risk of CKD (OR: 1.86, 95% CI: 1.48-2.34). Critical METS-VF thresholds (6.10 and 7.55) were identified, at which CKD risk increased substantially. Subgroup analyses indicated that the association was particularly pronounced among older adults and males. These findings suggest that METS-VF is a reliable predictor for assessing CKD risk and that lifestyle interventions, including dietary modifications and exercise programs, may mitigate this risk.

An eCIRP inhibitor attenuates fibrosis and ferroptosis in ischemia and reperfusion induced chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is a leading cause of death in the United States, and renal fibrosis represents a pathologic hallmark of CKD. Extracellular cold-inducible RNA-binding protein (eCIRP) is a stress response protein involved in acute inflammation, tissue injury and regulated cell death. However, the role of eCIRP in chronic inflammation and tissue injury has not been elucidated. We hypothesize that eCIRP is involved in renal ischemia/reperfusion (RIR)-induced CKD and that C23, an antagonist to eCIRP, is beneficial in attenuating renal fibrosis and ferroptosis in RIR-induced CKD.

METHODS

C57BL/6 (WT) or CIRP-/- mice underwent renal injury with total blockage of blood perfusion by clamping bilateral renal pedicles for 28 min. In the WT mice at the time of reperfusion, they were treated with C23 (8 mg/kg) or vehicle. Blood and kidneys were harvested for further analysis at 21 days thereafter. In a separate cohort, mice underwent bilateral RIR and treatment with C23 or vehicle and were then subjected to left nephrectomy 72 h thereafter. Mice were then monitored for additional 19 days, and glomerular filtration rate (GFR) was assessed using a noninvasive transcutaneous method.

RESULTS

In the RIR-induced CKD, CIRP-/- mice showed decreased collagen deposition, fibronectin staining, and renal injury as compared to the WT mice. Administration of C23 ameliorated renal fibrosis by decreasing the expression of active TGF-β1, α-SMA, collagen deposition, fibronectin and macrophage infiltration to the kidneys. Furthermore, intervention with C23 significantly decreased renal ferroptosis by reducing iron accumulation, increasing the expression of glutathione peroxidase 4 (GPX4) and lipid peroxidation in the kidneys of RIR-induced CKD mice. Treatment with C23 also attenuated BUN and creatinine. Finally, GFR was significantly decreased in RIR mice with left nephrectomy and C23 treatment partially prevented their decrease.

CONCLUSION

Our data show that eCIRP plays an important role in RIR-induced CKD. Treatment with C23 decreased renal inflammation, alleviated chronic renal injury and fibrosis, and inhibited ferroptosis in the RIR-induced CKD mice.

The Effect of Dietary Fiber on Hyperkalemia in Maintenance Hemodialysis Patients: A Cross-Sectional Study

OBJECTIVE

To explore the relationship between dietary fiber (DF) intake and hyperkalemia in maintenance hemodialysis (MHD) patients.

METHODS

A total of 110 MHD patients were included, including 67 males and 43 females. Patients were divided into normal serum potassium group (N) and a hyperkalemia group (H) according to the serum potassium level before dialysis. The daily diet was recorded by the 3-day dietary recording method. The daily dietary nutrient intake of patients was analyzed. Logistic regression was used to analyze the relationship between hyperkalemia and DF intake. A receiver operating characteristic curve was used to analyze the cutoff value of DF intake to prevent hyperkalemia.

RESULTS

Of the 110 patients, 38 had hyperkalemia (serum potassium >5.5 mmol/L) before dialysis. There was no difference in sex, residual kidney function, body mass index, energy intake, fat intake, protein intake, calcium intake, sodium intake, phosphorus intake or the administration history of potassium-lowering drugs between the 2 groups (P > .05). Compared with the H group, patients in the N group had higher carbohydrate intake (315 ± 76 g/d vs. 279 ± 66 g/d, P = .016), dietary fiber intake (19 ± 5 g/d vs. 12 ± 8 g/d, P < .0001), and potassium intake (1,698 ± 392 mg/d vs. 1,533 ± 413 mg/d, P = .041), and more patients in group N used renin-angiotensin-aldosterone system inhibitors (52.78% vs. 23.68%, P = .003). However, the number of patients with constipation in group N was less than that in group H (20.83% vs. 42.11%, P = .018). Logistic regression analysis showed that DF intake was an independent protective factor for hyperkalemia [P < .0001, odds ratio = 0.766 (95% confidence intervals: 0.675-0.870)]. Receiver operating characteristic analysis showed that daily intake of DF greater than 15.33 g may be helpful to prevent hyperkalemia.

CONCLUSION

Insufficient dietary nutrient intake is prevalent in MHD patients, especially DF intake, which may be associated with hyperkalemia. Clinically, attention should be given to the dietary balance of MHD patients, especially DF intake.

Exosomes derived from TREM-2 knocked-out macrophages alleviated renal fibrosis via HSPa1b/AKT pathway

Macrophages are recognized as vital players in renal fibrosis, with a high degree of heterogeneity and plasticity, and the triggering receptor expressed on myeloid cell-2 (TREM-2) is highly expressed on macrophages and participates in the progression of tissue fibrosis. However, the mechanism by which TREM-2 mediates the progression of renal fibrosis is still unclear. Our study revealed that exosomes derived from TREM-2-deficient (TREM-2-/-) macrophages suppressed the progression of fibrosis, as indicated by a greater matrix metalloproteinase-9 (MMP-9)/tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) ratio at the protein level in secreted exosomes than in exosomes from wild-type (WT) macrophages in the fibrotic microenvironment. In addition, renal tubular epithelial cells (TECs) engulfed these nanoscale vesicles, and the expression of collagen I and α-smooth muscle actin (α-SMA) (a fibrosis-related marker) was obviously decreased. Through RNA-seq, we found that TREM-2-/- macrophages increase the MMP-9/TIMP-1 ratio in their exosomes via the heat shock protein a1b (HSPa1b)/AKT pathway. Notably, renal fibrosis was effectively alleviated in the obstructed kidneys of mice that received a renal pelvis injection of an adeno-associated virus (AAV-shTREM-2) containing the sequence used to silence TREM-2. However, VER-155008 (an inhibitor of HSPa1b) and Ly294002 (an inhibitor of AKT) reversed this effect. Moreover, polyclonal antibodies against TREM-2 also effectively relieved unilateral ureteral obstruction (UUO)-induced renal fibrosis. Overall, we validated that knocking down TREM-2 expression can inhibit the progression of renal fibrosis through a macrophage exosome-dependent pathway both in vitro and in vivo. Hence, our findings suggest that TREM-2 is a potential therapeutic target for chronic kidney disease (CKD).NEW & NOTEWORTHY Renal fibrosis is a common pathological feature of CKD, resulting in irreversible loss of function and structure. However, effective therapies for CKD are currently limited. We found that the deletion of TREM-2 in macrophages increased the MMP-9/TIMP-1 ratio in exosomes, shifting toward the degradation of the extracellular matrix (ECM) and the alleviation of renal fibrosis. Furthermore, polyclonal antibodies against TREM-2 effectively suppressed renal fibrosis. These findings provide evidence that TREM-2 is a potential therapeutic target for CKD.

Renal T1 Times on Cardiac Magnetic Resonance Reflect Renal Dysfunction and Are Associated with Adverse Outcomes: Insights from an All-Comer Cohort

Background: Renal disease is common in patients with cardiovascular disease (CVD) and is associated with adverse outcomes. Cardiac magnetic resonance (CMR) with advanced mapping techniques is the gold standard for characterizing myocardial tissue, and renal tissue is often visualized on these maps. However, it remains unclear whether renal T1 times accurately reflect renal dysfunction or predict adverse outcomes. Aim: To analyze the relationship between renal T1 times, renal dysfunction, and adverse outcomes. Adverse outcomes were defined as all-cause and cardiovascular death. Methods: Renal T1 times were measured in the native short-axis view in an all-comers cohort undergoing CMR. Renal function parameters were assessed at the time of CMR. Results: A total of 506 patients (mean age 60 ± 15 years, 53% male) were included in the analysis. A significant correlation was observed between log10 renal cortical T1 times and eGFR (r = -0.701, p < 0.001) and creatinine (r = 0.615, p < 0.001). Kaplan-Meier analysis showed an increased risk of all-cause (p < 0.001 by log-rank test) and cardiovascular mortality (p = 0.004 by log-rank test) in patients with renal cortical T1 times above the median. In the univariable Cox regression analysis, there was a significant association between renal cortical T1 times and increased risk of all-cause (HR = 1.73 [95% CI, 1.42-2.11] per every 100 ms increase p < 0.001) and cardiovascular mortality (HR = 1.41 [95% CI, 1.05-1.90] per every 100 ms increase, p = 0.021). This association remained statistically significant after adjustment for prespecified clinical factors (adjusted HR for all-cause death = 1.49 [95% CI, 1.10-2.02] per every 100 ms increase, p = 0.01; adjusted HR for cardiovascular death = 1.42 [95% CI, 1.05-1.90] per every 100 ms increase, p = 0.021). Conclusions: Our results indicate that there is a significant association between increased renal cortical T1 times and impaired renal function, as well as an increased risk of all-cause and cardiovascular mortality, although it should be noted that our results are preliminary and need to be validated in external cohorts performing renal biopsies.

Epidemiological shifts in chronic kidney disease: a 30-year global and regional assessment

BACKGROUND

Chronic kidney disease (CKD) presents a growing global health challenge, with significant variability in disease burden across different regions and countries. This study aimed to analyze the trends in incidence, prevalence, mortality, and disability-adjusted life years (DALYs) for CKD from 1990 to 2019, utilizing data from the Global Burden of Disease Study.

METHODS

We conducted an in-depth study on the global and age-standardized incidence, prevalence, mortality, and DALYs of CKD, and assessed trends over a 30-year period. Additionally, we explored the associations between healthcare access and quality (HAQ), the Socio-Demographic Index (SDI), and CKD. Furthermore, we conducted a detailed analysis of six risk factors closely related to CKD, and based on these findings, provided strong evidence for enhancing the management of CKD.

RESULTS

In 2019, there were 18,986,903 cases of CKD, with an average annual percent change (AAPC) of 1.82 (95% CI = 1.8 to 1.82) in incidence since 1990. The age-standardized incidence rate increased from 192.45 per 100,000 in 1990 to 233.65 per 100,000 in 2019. Prevalence also rose, with a total of 69,729,430 cases in 2019 and an AAPC of 1.19 (95% CI = 1.19 to 1.2). Mortality and DALYs have increased correspondingly, with the mortality rate reaching 18.29 per 100,000 and total DALYs at 41,538,592 in 2019. The analysis showed that higher HAQ levels are associated with better outcomes in terms of lower mortality and DALY rates, whereas lower HAQ levels correlate with poorer outcomes. In addition, high fasting plasma glucose and high systolic blood pressure are the main contributors to CKD-related deaths, with their population attributable fraction (PAF) significantly decreasing as the SDI decreases.

CONCLUSION

The burden of CKD has significantly increased over the past three decades, influenced by demographic changes and variations in healthcare quality and access. Effective public health strategies and improvements in healthcare delivery are needed to address the disparities in CKD outcomes globally.

Patient-related factors that link chronic kidney disease and periodontitis: a scoping review

Several studies have proposed the existence of an association between periodontitis and chronic kidney disease (CKD) based on biological premises. There is growing evidence that chronic inflammation caused by periodontitis may contribute to the progression of CKD. The present study aimed to investigate studies that link CKD and periodontitis, including periodontitis proxies such as oral hygiene and tooth loss, and patient-related factors such as inflammatory response and genetic polymorphisms. An electronic search was conducted on the MEDLINE (Pubmed), Cochrane Central Register of Controlled Trials (CENTRAL), Scopus, and Web of Science databases using an advanced search option up until August 2024. Thirty-two studies were included: 4 interventional, 16 cohort, and 12 case-control. Overall, the prevalence of periodontitis was significantly higher in patients with CKD: the diagnosis of periodontal disease was associated with an increase in the risk of incident CKD, and parameters of periodontal disease were negatively correlated with kidney function. Inside the field of periodontal medicine, the current evidence indicates a possible association between CKD and periodontitis and supports future longitudinal studies to investigate the two-way relationship between the diseases and their pathophysiology, and possibly to establish cause and effect.

Cross-country inequalities in disease burden and care quality of chronic kidney disease due to type 2 diabetes mellitus, 1990-2021: Findings from the global burden of disease study 2021

AIM

To explore the trend of burden and care quality of chronic kidney disease due to type 2 diabetes mellitus (CKD-T2DM) and their cross-country inequalities from 1990 to 2021.

MATERIALS AND METHODS

Data were from the Global Burden of Disease 2021 study. Disease burden and care quality were quantified using the disability-adjusted life years rate and the quality-of-care index (QCI). Trend analyses of the age-standardized disability-adjusted life years rate (ASDR) and age-standardized QCI from 1990 to 2021 were conducted using the estimated annual percentage change. The associations of disease burden and care quality with the socio-demographic index (SDI) were explored. Cross-country inequalities in disease burden and care quality were assessed using the slope index of inequality (SII) and concentration index.

RESULTS

From 1990 to 2021, the global ASDR for CKD-T2DM increased, while the age-standardized QCI slightly decreased, with an estimated annual percentage change of 0.81 [95% confidence interval (CI): 0.75, 0.87] and -0.08 (95% CI: -0.09, -0.07). The ASDR escalated with increasing SDI, reaching a peak at mid-level SDI, followed by a decrease. The age-standardized QCI was higher with increasing SDI. Globally, ASDR concentrated on countries/territories with a lower SDI. The SII of ASDR was -96.64 (95% CI: -136.94, -56.35) in 1990 and -118.15 (95% CI: -166.36, -69.94) in 2021,  with a concentration index of -0.1298 (95% CI: -0.1904, -0.0692) in 1990 and -0.1104 (95% CI: -0.1819, -0.0389) in 2021. In 1990 and 2021, countries/territories at higher SDI levels exhibited increased age-standardized QCI, indicated by an SII of 15.09 (95% CI: 10.74, 19.45) and 15.75 (95% CI: 10.92, 20.59), and a concentration index of 0.0393 (95% CI: 0.0283, 0.0503) and 0.0400 (95% CI: 0.0264, 0.0536).

CONCLUSIONS

Our study highlights considerable disparities in the burden and care quality of CKD-T2DM. Regions experiencing an increasing burden and a declining care quality simultaneously underscore the need for further research and tailored health interventions.

Impaired sensitivity to thyroid hormones is associated with all-cause and cause-specific mortality among chronic kidney disease patients: results from National Health and Nutrition Examination Survey (NHANES) 2007-2012

BACKGROUND

Resistance to thyroid hormone shows underlying mechanical link with chronic kidney disease (CKD) and is prevalent in CKD population. However, whether it attributes to mortality risk among CKD population is unknown. This study aimed to examine the association of thyroid hormone resistance (THR) with all-cause and cause-specific mortality among CKD individuals.

METHODS

This study extracted CKD population from the National Health and Nutrition Examination Survey (NHANES) 2007-2012. Death outcomes were ascertained by linkage to National Death Index records through 31 December 2019. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence interval (CI) for mortality from all causes, cardiovascular disease (CVD).

RESULTS

A total of 1,634 adults with CKD were included in the cohort, in which 663 deaths were recorded during an average follow-up of 8.72 years. After multivariate adjustment, resistance to thyroid hormone was significantly associated with higher all-cause and CVD mortality. There was an 18% and 31% increase in risks of all-cause and CVD mortality per-standard deviation (SD) increment in Parametric Thyroid Feedback Quantile-based Index (PTFQI) respectively. When PTFQI was analyzed as categorical variable (classified according to PTFQI percentiles), after adjusted for potential confounders and taking PTFQI ≤ P5 as reference, the HRs and 95% CIs in category with PTFQI > P95 for all-cause mortality and CVD mortality were 2.12 [1.10, 4.09] (p for trend 0.026) and 5.14 [1.81, 14.60] for (p for trend 0.018), respectively.

CONCLUSIONS

Resistance to thyroid hormone, centered on variations in the typical pituitary response to thyroid hormones, may independently correlate with all-cause and CVD mortality in CKD patients.

Association of life's essential 8 with prevalence and all-cause mortality of chronic kidney disease among US adults: Results from the National Health and Nutrition Examination Survey (2015-2018)

Background and Objectives

The association between chronic kidney disease (CKD) and cardiovascular disease has been previously evaluated. This study aimed to evaluate the association between the American Heart Association's Life's Essential 8 (LE8) and the prevalence and all-cause mortality of CKD in a nationally representative population of adults in the US.

Methods

This retrospective analysis included participants from the National Health and Nutrition Examination Survey spanning 2015-2018. We used multivariable survey logistic regression model to calculate the adjusted odds ratios (AORs) of the LE8 score for the prevalence of CKD. Survey-weighted Cox proportional hazards models were used to calculate the adjusted hazards ratios (AHRs) of the LE8 score for the risk of all-cause mortality among participants with CKD.

Results

Of the 8907 included participants, 789 had stage 3 to 5 CKD, and 8118 were in the non-CKD group. The adjusted prevalence rate of CKD was 10.7% in the low LE8 score group, and lower in the moderate (7.9%) and high (7.7%) LE8 score groups. Compared with low LE8 scores, moderate LE8 score (adjusted odds ratio [AOR] 0.628, 95% confidence interval [CI]: 0.463 to 0.853, P = 0.004) and high LE8 scores (AOR 0.328, 95% CI: 0.142 to 0.759, P = 0.011) were associated with lower prevalence rates of CKD. A similar association was found for health factors scores. Additionally, an increase in the LE8 score was associated with a lower risk of all-cause mortality (adjusted hazard ratio [AHR] 0.702, 95% CI: 0.594 to 0.829, P < 0.001).

Conclusion

The results of this study suggest the association of higher LE8 and its subscale scores with a lower prevalence and all-cause mortality of CKD.

Effectiveness and safety of finerenone in Chinese CKD patients without diabetes: a retrospective, real-world study

BACKGROUND

Finerenone, a non-steroidal mineralocorticoid receptor antagonist, has previously demonstrated its efficacy and safety in chronic kidney disease (CKD) associated with diabetes mellitus. Given its therapeutic potential, finerenone has been preliminarily explored in clinical practice for non-diabetic CKD patients. The effectiveness and safety in this population require further investigation in a real-world setting.

METHODS

This retrospective, real-world analysis included non-diabetic CKD patients receiving finerenone. The main clinical outcomes assessed were changes in urinary albumin-to-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR). Serum potassium (sK+) levels were also monitored. Data were collected at baseline, and then at 1 month and 3 months following treatment initiation.

RESULTS

Totally, 16 patients were included. There was a notable decrease in UACR from 1-month post-treatment, with a further reduction at 3 months, resulting in a median reduction of 200.41 mg/g (IQR, 84.04-1057.10 mg/g; P = 0.028; percent change, 44.52% [IQR, 31.79-65.42%]). The average eGFR at baseline was 80.16 ml/min/1.73m2, with no significant change after 1 month (80.72 ml/min/1.73m2, P = 0.594) and a slight numerical increase to 83.45 ml/min/1.73m2 (P = 0.484) after 3 months. During the 3-month follow-up, sK+ levels showed only minor fluctuations, with no significant differences compared to baseline, and remained within the normal range throughout the treatment period. No treatment discontinuation or hospitalization due to hyperkalemia was observed.

CONCLUSION

In non-diabetic CKD patients, finerenone showed good effectiveness and safety within a 3-month follow-up period. This study provides valuable real-world evidence supporting the use of finerenone in non-diabetic CKD and highlights the need for future large-scale prospective research to further validate its efficacy.

Epidemiological analysis of chronic kidney disease from 1990 to 2019 and predictions to 2030 by Bayesian age-period-cohort analysis

BACKGROUND

Chronic Kidney Disease (CKD) has emerged as a significant global health issue. This study aimed to reveal and predict the epidemiological characteristics of CKD.

METHODS

Data from the Global Burden of Disease Study spanning the years 1990 to 2019 were employed to analyze the incidence, prevalence, death, and disability-adjusted life year (DALY) of CKD. Joinpoint analysis assessed epidemiological trends of CKD from 1990 to 2019. An age-period-cohort model evaluated risk variations. Risk factor analysis uncovered their influences on DALYs and deaths of CKD. Decomposition analysis explored the drivers to CKD. Frontier analysis evaluated the correlations between CKD burden and the sociodemographic index (SDI). A Bayesian Age-Period-Cohort model was employed to predict future incidence and death of CKD.

RESULTS

In 2019, there were 18,986,903 incident cases, 697,294,307 prevalent cases, 1,427,232 deaths, and 41,538,592 DALYs of CKD globally. Joinpoint analysis showed increasing age-standardized rates of CKD incidence, prevalence, mortality, and DALY from 1990 to 2019. High systolic blood pressure significantly contributed to CKD-related deaths and DALYs, particularly in the high SDI region. Decomposition analysis identified population growth as the primary driver of CKD incident cases and DALYs globally. Countries like Nicaragua showed the highest effective differences, indicating room for improvement in CKD management. By 2030, while incident cases of CKD were predicted to rise, the global deaths might decrease.

CONCLUSIONS

The study revealed a concerning upward trend in the global burden of CKD, emphasizing the need for targeted management strategies across different causes, regions, age groups, and genders.

Cost-effectiveness of dapagliflozin plus standard treatment compared to standard therapy for the management of chronic kidney disease in Colombia

BACKGROUND

The DAPA-CKD study showed that dapagliflozin added to standard treatment reduced the risk of chronic kidney disease progression, and death from renal or cardiovascular causes compared to placebo.

OBJECTIVE

Assess the cost-effectiveness of dapagliflozin and standard treatment versus standard treatment alone for chronic kidney disease within the Colombian health system.

METHODS

We employed a Markov model based on the DAPA-CKD study, tailored to the Colombian scenario. The model forecasted hospitalizations for heart failure, overall and cardiovascular mortality, and chronic kidney disease progression over a 10-year horizon with a 5% discount rate.

RESULTS

Dapagliflozin combined with standard treatment is a cost-effective intervention in treating stage 2-4 CKD. In the base case, the ICER was US $5,366, below 1 GDP (US $6.558) per capita. This was consistent in the sensitivity analyses.

CONCLUSION

Our study showed that dapagliflozin, when combined with standard treatment, is cost-effective against standard treatment alone, aligning with Colombia's willingness-to-pay threshold.

The association between monocyte to high-density lipoprotein cholesterol ratio and chronic kidney disease in a Chinese adult population: a cross-sectional study

BACKGROUND

Monocyte to high-density lipoprotein cholesterol ratio (MHR) was confirmed as a novel inflammatory marker and strongly associated with the risk of several diseases. This study aimed to investigate the relationship between MHR and chronic kidney disease (CKD) in a Chinese adult population.

METHODS

In this cross-sectional study, 232,775 community-dwelling adults in Binhai who completed health checkups in 2021 were enrolled. Participants were categorized based on the MHR quartiles. Clinical characteristics of participants across different groups were compared using one-way ANOVA, Kruskal-Wallis h-test, and Chi-squared test as appropriate. Univariate and multivariable logistic regression analyses were taken to assess the relationship between MHR and the presence of CKD, as well as its association with low estimated glomerular filtration rate (eGFR) and proteinuria. Subgroup analyses were further executed to confirm the reliability of this relationship.

RESULTS

A total of 21,014 (9.0%) individuals were diagnosed with CKD. Characteristic indicators including waist circumference, body mass index (BMI), blood pressure (BP), serum uric acid (SUA), triglyceride, and fasting blood glucose (FBG) showed a gradual increase with higher MHR quartiles, whereas parameters such as age, total cholesterol, high-density lipoprotein cholesterol (HDL-C), and eGFR decreased (p < .001). In the multivariable logistic regression analysis, we observed independent associations between MHR (per 1 SD increase) and CKD, as well as low eGFR and proteinuria, with odds ratio (ORs) and 95% confidence intervals (95%CIs) of 1.206 (1.186-1.225), 1.289 (1.260-1.319), and 1.150 (1.129-1.171), respectively (p < .001). Similar conclusions were confirmed in subgroup analysis stratified by gender, age, BMI, central obesity, hypertension, and diabetes mellitus, after justification for confounding factors.

CONCLUSION

Elevated MHR level was independently associated with the presence of CKD, suggesting that it might serve as a useful clinical tool for risk stratification, offering valuable insights to inform preventive and therapeutic approaches for clinicians in their routine medical practice.

Transcription factor Twist1 drives fibroblast activation to promote kidney fibrosis via signaling proteins Prrx1/TNC

The transcription factor Twist1 plays a vital role in normal development in many tissue systems and continues to be important throughout life. However, inappropriate Twist1 activity has been associated with kidney injury and fibrosis, though the underlying mechanisms involved remain incomplete. Here, we explored the role of Twist1 in regulating fibroblast behaviors and the development kidney fibrosis. Initially Twist1 protein and activity was found to be markedly increased within interstitial myofibroblasts in fibrotic kidneys in both humans and rodents. Treatment of rat kidney interstitial fibroblasts with transforming growth factor-β1 (a profibrotic factor) also induced Twist1 expression in vitro. Gain- and loss-of-function experiments supported that Twist1 signaling was responsible for transforming growth factor-β1-induced fibroblast activation and fetal bovine serum-induced fibroblast proliferation. Mechanistically, Twist1 protein promoted kidney fibroblast activation by driving the expression of downstream signaling proteins, Prrx1 and Tnc. Twist1 directly enhanced binding to the promoter of Prrx1 but not TNC, whereas the promoter of TNC was directly bound by Prrx1. Finally, mice with fibroblast-specific deletion of Twist1 exhibited less Prrx1 and TNC protein abundance, interstitial extracellular matrix deposition and kidney inflammation in both the unilateral ureteral obstruction and ischemic-reperfusion injury-induced-kidney fibrotic models. Inhibition of Twist1 signaling with Harmine, a β-carboline alkaloid, improved extracellular matrix deposition in both injury models. Thus, our results suggest that Twist1 signaling promotes the activation and proliferation of kidney fibroblasts, contributing to the development of interstitial fibrosis, offering a potential therapeutic target for chronic kidney disease.

Cardio-renal protective effect and safety of sodium-glucose cotransporter 2 inhibitors for chronic kidney disease patients with eGFR < 60 mL/min/1.73 m2: a systematic review and meta-analysis

OBJECTIVE

This meta-analysis was designed to investigate cardio-renal outcomes and safety of sodium-glucose cotransporter-2 inhibitors (SGLT2i) as a therapeutic option among chronic kidney disease(CKD) patients with GFR < 60 mL/min/1.73 m2, regardless of their diabetic status.

METHOD

We conducted a full-scale search from MEDLINE, EMBASE and the Cochrane Library database to identify eligible studies up to Jun 2024. All randomized controlled trials (RCTs) comparing cardio-renal outcomes and/or safety of SGLT2i in CKD patients with eGFR < 60 mL/min/1.73 m2 were involved. The relative risk (RR) and 95% confidence interval (CI) for primary outcomes and adverse events were computed by random-effects mode. We used I2 statistic to analyze heterogeneity. Publication bias was assessed by Egger's test.

RESULTS

Our study incorporated 17 RCTS, including 27,928 patients. In CKD patients with eGFR < 60 mL/min/1.73 m2, SGLT2i decreased risks of cardiovascular events (seven studies, 17,355 participants, RR 0.77, 95% CI 0.70-0.84), hospitalization for heart failure (HHF) (seven studies, 17,869 participants, RR 0.73, 95% CI 0.65-0.82), cardiovascular death (eight studies, 23,079 participants, RR 0.81, 95% CI 0.74 to 0.88) and renal composite outcomes (eight studies, 22,525 participants, RR 0.70, 95% CI 0.61-0.80) with lower risks of any serious adverse effects(fourteen studies, 19,654 participants, RR 0.91, 95% CI 0.87-0.95), hypoglycemia (nine studies, 16,412 participants, RR 0.91, 95% CI 0.84-0.98), hyperkalemia (four studies, 2693 participants, RR 0.68, 95% CI 0.51-0.93) and acute renal injury (five studies, 5424 participants, RR 0.79, 95% CI 0.65-0.95) compared to placebo. SGLT2i also slowed eGFR decline (total slopes: five studies, 10,370 participants, mean difference 1.17, 95%CI 0.86-1.49; chronic slopes: four studies, 8459 participants, mean difference 2.12, 95%CI 1.64-2.61). Further subgroup analyses revealed that SGLT2i decreased relative risks of cardiovascular outcomes(three studies, 1075 participants, RR 0.76, 95% CI 0.54-0.82), HHF(four studies, 1280 participants, RR 0.74, 95% CI 0.55-1.00) and renal composite outcomes (six studies,4375 participants, RR 0.78, 95% CI 0.68-0.88) with no increased adverse events in the CKD 4 patients.

CONCLUSIONS

SGLT2i significantly improved cardio-renal outcomes and were generally safe in CKD patients with eGFR < 60 mL/min/1.73 m2 and with eGFR < 30 mL/min/1.73 m2. Future large-scale RCTs are needed to confirm the robustness of these results.

What every clinician needs to know about chronic kidney disease: Detection, classification and epidemiology

Chronic kidney disease (CKD) is a major healthcare challenge, affecting >800 million people worldwide. Implications for population health result from the strong associations of CKD with increased rates of cardiovascular disease, heart failure, progressive CKD leading to kidney failure, acute kidney injury (AKI), and mortality. In addition to a single disease perspective, CKD commonly coexists alongside other long-term conditions, in particular type 2 diabetes and cardiovascular disease. CKD is therefore an important component of multimorbidity that influences individual management and impacts prognosis. CKD is defined by abnormalities of kidney structure or function of any cause with implications for health that are present for longer than 3 months. The diagnosis is usually made on the basis of an abnormal glomerular filtration rate (GFR < 60 mL/min/1.73 m2) and/or the presence of proteinuria (urine albumin to creatinine ratio > 30 mg/g or >3 mg/mmol). GFR is usually estimated from serum creatinine concentration using a variety of validated equations. However, serum creatinine is closely related to muscle mass and may therefore not be an accurate marker of GFR in people with high or low muscle mass (sarcopaenia). Cystatin C is an alternative endogenous marker of GFR that is increasingly being used but also has limitations. An estimate of GFR based on both creatinine and cystatin C is the most accurate. Diagnosis should be followed by classification and risk stratification to guide the development of a risk-based, personalized care plan. Improved detection and widespread implementation of optimal CKD management has the potential to bring major benefits to population health.

TRIM65 deficiency alleviates renal fibrosis through NUDT21-mediated alternative polyadenylation

Chronic kidney disease (CKD) is a major global health concern and the third leading cause of premature death. Renal fibrosis is the primary process driving the progression of CKD, but the mechanisms behind it are not fully understood, making treatment options limited. Here, we find that the E3 ligase TRIM65 is a positive regulator of renal fibrosis. Deletion of TRIM65 results in a reduction of pathological lesions and renal fibrosis in mouse models of kidney fibrosis induced by unilateral ureteral obstruction (UUO)- and folic acid. Through screening with a yeast-hybrid system, we identify a new interactor of TRIM65, the mammalian cleavage factor I subunit CFIm25 (NUDT21), which plays a crucial role in fibrosis through alternative polyadenylation (APA). TRIM65 interacts with NUDT21 to induce K48-linked polyubiquitination of lysine 56 and proteasomal degradation, leading to the inhibition of TGF-β1-mediated SMAD and ERK1/2 signaling pathways. The degradation of NUDT21 subsequently altered the length and sequence content of the 3'UTR (3'UTR-APA) of several pro-fibrotic genes including Col1a1, Fn-1, Tgfbr1, Wnt5a, and Fzd2. Furthermore, reducing NUDT21 expression via hydrodynamic renal pelvis injection of adeno-associated virus 9 (AAV9) exacerbated UUO-induced renal fibrosis in the normal mouse kidneys and blocked the protective effect of TRIM65 deletion. These findings suggest that TRIM65 promotes renal fibrosis by regulating NUDT21-mediated APA and highlight TRIM65 as a potential target for reducing renal fibrosis in CKD patients.

The efficacy and safety of retrograde ureteral stenting in the management of complicated cases of ureteral obstruction caused by urolithiasis

PURPOSE

To investigate the efficacy and safety of retrograde double J stent (RDJS) placement in the management of complicated obstructive uropathy caused by urolithiasis.

PATIENTS AND METHODS

An observational study done at a tertiary center was implemented in which a total of 27 patients (10 males, 17 females) with average age of 48.74 years (range: 15-88) who underwent RDJS or percutaneous nephrostomy (PCN) between 2017 and 2021 due to complicated obstruction caused by urolithiasis were included.

RESULTS

A total of 27 patients (10 males, 17 females) with average age of 48.74 years (range: 15-88) who underwent kidney decompression between 2017 and 2021 due to complicated unilateral or bilateral kidney obstruction caused by ureteral stones were included. Twenty-two patients (81.48%) underwent successful RDJS placement, two patients had RDJS placement then PCN was also placed, and two patients underwent PCN placement. Three patients needed an intensive care unit "ICU" after intervention, two of them were in the ICU before intervention. All septic parameters were normalized within a short period postoperatively. Two patients with failed previous ureteroscopy had a successful RDJS placement.

CONCLUSION

Retrograde DJS placement is a feasible option in the management of complicated cases of obstructive uropathy caused by urolithiasis. Short hospitalization period, low rate of complications and better quality of life are the most prominent advantages of RDJS placement. In the hands of experienced surgeons, RDJS should be offered as the first choice of decompression for obstructive uropathy caused by urolithiasis.

Exosomal let-7b-5p deriving from parietal epithelial cells attenuate renal fibrosis through suppression of TGFβR1 and ARID3a in obstructive kidney disease

As renal progenitor cells, parietal epithelial cells (PECs) have demonstrated multilineage differentiation potential in response to kidney injury. However, the function of exosomes derived from PECs has not been extensively explored. Immunofluorescent staining of Claudin-1 was used to identify primary PECs isolated from mouse glomeruli. Transmission electron microscopy, nanoparticle tracking analysis, and western blotting were used to characterize the properties of PECs-derived exosomes (PEC-Exo). The therapeutic role of PEC-Exo in tubulointerstitial fibrosis was investigated in the unilateral ureteral obstruction (UUO) mouse model and TGF-β1-stimulated HK-2 cells. High-throughput miRNA sequencing was employed to profile PEC-Exo miRNAs. One of the most enriched miRNAs in PEC-Exo was knocked down by transfecting miRNA inhibitor, and then we investigated whether this candidate miRNA was involved in PEC-Exo-mediated tubular repair. The primary PECs expressed Claudin-1, PEC-Exo was homing to obstructed kidney, and TGF-β1 induced HK-2 cells. PEC-Exo significantly alleviated renal inflammation and ameliorated tubular fibrosis both in vivo and in vitro. Mechanistically, let-7b-5p, highly enriched in PEC-Exo, downregulated the protein levels of transforming growth factor beta receptor 1(TGFβR1) and AT-Rich Interaction Domain 3A(ARID3a) in tubular epithelial cells (TECs), leading to the inhibition of p21 and p27 to restoring cell cycle. Furthermore, administration of let-7b-5p agomir mitigated renal fibrosis in vivo. Our findings demonstrated that PEC-derived exosomes significantly repressed the expression of TGFβR1 and ARID3a by delivering let-7b-5p, thereby alleviating renal fibrosis. This study provides novel insights into the role of PEC-Exo in the repair of kidney injury and new ideas for renal fibrosis intervention.

SGLT2 inhibitor downregulated oxidative stress via activating AMPK pathway for cardiorenal (CR) protection in CR syndrome rodent fed with high protein diet

This study tested the hypothesis that empagliflozin (EMPA) therapy effectively protected renal and heart functions via downregulating reactive oxygen species (ROS) and activating AMPK signaling in cardiorenal syndrome (CRS) (induced by doxorubicin-5/6 nephrectomy) rats. In vitro result showed that underwent p-Cresol treatment, the H9C2/NRK-52E cell viabilities, were significantly suppressed, whereas cellular levels of ROS and early/late apoptosis of these cells were significantly increased that were significantly reversed by EMPA treatment (all p < 0.001). The protein levels of the cell-stress/oxidative signaling (p-PI3K/p-Akt/p-mTOR/NOXs/p-DRP1) were significantly activated, whereas the mitochondrial biogenesis signaling (p-AMPK/SIRT-1/TFAM/PGC-1α) was significantly repressed in these two cell lines treated by p-Cresol and all of these were significantly reversed by EMPA treatment (all p < 0.001). Male-adult-SD rats were categorized into groups 1 [sham-operated control (SC)]/2 [SC + high protein diet (HPD) since day 1 after CKD induction]/3 (CRS + HPD)/4 (CRS + HPD+EMPA/20 mg/kg/day) and heart/kidney were harvested by day 60. By day 63, the renal function parameters (creatinine/BUN/proteinuria)/renal artery restrictive index/cellular levels of ROS/inflammation were significantly increased in group 3 than in groups 1/2, whereas heart function exhibited an opposite pattern of ROS among the groups, and all of these parameters were significantly reversed by EMPA treatment (all p < 0.0001). The protein levels of inflammation/ oxidative-stress/cell-stress signalings were highest in group 2, lowest in group 1 and significantly lower in group 4 than in group 2, whereas the AMPK-mitochondrial biogenesis displayed an opposite manner of oxidative-stress among the groups (all p < 0.0001). EMPA treatment effectively protected the heart/kidney against CRS damage via suppressing ROS signaling and upregulating AMPK-mediated mitochondrial biogenesis.

Therapeutic effects of Kangxian Yanshen formula on patients with chronic kidney disease stages 3-4: a retrospective cohort study

Background

This study retrospectively evaluated the actual efficacy of Kangxian Yanshen Formula Chinese medicine on renal function-related indicators in chronic kidney disease (CKD) stage 3-4 patients.

Methods

In this retrospective cohort study, we collected 212 adult CKD patients with baseline estimated glomerular filtration rate (eGFR) of 15-60 ml/min/1.73 m2. All participants received usual care (i.e., Western medications), and participants in the exposure group (n = 109) were additionally prescribed Kangxian Yanshen Formula Chinese medicine. The primary outcome was an adjusted hazard risk and 95% confidence interval (95% CI) of a 30% decrease in eGFR at month 36 from baseline.

Results

In terms of eGFR, among participants treated with additional Kangxian Yanshen Formula, after adjusting for covariates, there was a 57.1% reduction in the risk of a 30% decline from baseline in eGFR among participants in the Kangxian Yanshen Formula group compared with the Western medicine group (adjusted hazard risk: 0.429; 95% CI 0.269-0.682). In addition, participants in the Kangxian Yanshen Formula group had a significantly higher change in eGFR from baseline to month 12 than those in the western medicine group (3.40 ± 11.62 versus -3.87 ± 8.39; between-group difference Δ5.61 [± 2.26 standard deviation] mL/min/1.73 m2; P = 0.014). Participants in both groups showed a decreasing trend in eGFR at months 24 and 36.

Conclusion

In patients with stage 3-4 CKD, Kangxian Yanshen Formula Chinese medicine therapy may help delay eGFR decline, but high-quality randomized controlled trials are needed to validate the results further.