Renal outcome in multiple myeloma patients with cast nephropathy: a retrospective analysis of potential predictive values on clinical and renal outcome

OBJECTIVE

Cast nephropathy (CN) is the leading cause of acute kidney injury (AKI) in multiple myeloma (MM). Since it is sparsely documented why some patients with CN do achieve a renal response while others do not, we describe a single-center cohort of patients with multiple myeloma and biopsy-confirmed CN to evaluate potential markers of renal response.

METHODS

The data was collected as a retrospective, single-center analysis of CN-patients treated at the Medical University Vienna between 01/01/2004 and 01/01/2022. Baseline parameters and clinical outcome was compared between renal responders and non-responders.

RESULTS

Among 28 patients with CN, n = 23 were assessed for renal response (14 responders; 9 non-responders). Renal responders were younger (median age: 61 years; 77 years, p = 0.039), showed higher overall survival (153months; 58months, p = 0.044) and achieved hematologic response (≥PR) to first-line therapy (p = 0.029), and complete hematologic response (CR) at any time (p = 0.025) significantly more often. Further, we could show that rapid initiation of anti-myeloma therapy after initial presentation correlated significantly with renal response (median 9 days; 27 days, p = 0.016). Analyses of kidney biopsy specimens revealed that patients with a high IF/TA score showed end stage renal disease (dialysis ≥ 3 months) significantly more often (p = <0.001).

DISCUSSION

In summary, our data suggests, that a rapid start with systemic hematologic treatment in patients with MM and CN is crucial and achieving an early hematologic response is important for renal recovery. Moreover, achieving a deep hematologic response and subsequent renal recovery improves clinical outcome as reflected by an overall survival benefit.

Canagliflozin attenuates kidney injury, gut-derived toxins, and gut microbiota imbalance in high-salt diet-fed Dahl salt-sensitive rats

PURPOSE

To investigate the effects of canagliflozin (20 mg/kg) on Dahl salt-sensitive (DSS) rat gut microbiota and salt-sensitive hypertension-induced kidney injury and further explore its possible mechanism.

METHODS

Rats were fed a high-salt diet to induce hypertension and kidney injury, and physical and physiological indicators were measured afterwards. This study employed 16S rRNA sequencing technology and liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based metabolic profiling combined with advanced differential and association analyses to investigate the correlation between the microbiome and the metabolome in male DSS rats.

RESULTS

A high-salt diet disrupted the balance of the intestinal flora and increased toxic metabolites (methyhistidines, creatinine, homocitrulline, and indoxyl sulfate), resulting in severe kidney damage. Canagliflozin contributed to reconstructing the intestinal flora of DSS rats by significantly increasing the abundance of Corynebacterium spp., Bifidobacterium spp., Facklamia spp., Lactobacillus spp., Ruminococcus spp., Blautia spp., Coprococcus spp., and Allobaculum spp. Moreover, the reconstruction of the intestinal microbiota led to significant changes in host amino acid metabolite concentrations. The concentration of uremic toxins, such as methyhistidines, creatinine, and homocitrulline, in the serum of rats was decreased by canagliflozin, which resulted in oxidative stress and renal injury alleviation.

CONCLUSION

Canagliflozin may change the production of metabolites and reduce the level of uremic toxins in the blood circulation by reconstructing the intestinal flora of DSS rats fed a high-salt diet, ultimately alleviating oxidative stress and renal injury.

The combination of kidney function variables with cell cycle arrest biomarkers identifies distinct subphenotypes of sepsis-associated acute kidney injury: a post-hoc analysis (the PHENAKI study)

BACKGROUND

The severity and course of sepsis-associated acute kidney injury (SA-AKI) are correlated with the mortality rate. Early detection of SA-AKI subphenotypes might facilitate the rapid provision of individualized care.

PATIENTS AND METHODS

In this post-hoc analysis of a multicenter prospective study, we combined conventional kidney function variables with serial measurements of urine (tissue inhibitor of metalloproteinase-2 [TIMP-2])* (insulin-like growth factor-binding protein [IGFBP7]) at 0, 6, 12, and 24 h) and then using an unsupervised hierarchical clustering of principal components (HCPC) approach to identify different phenotypes of SA-AKI. We then compared the subphenotypes with regard to a composite outcome of in-hospital death or the initiation of renal replacement therapy (RRT).

RESULTS

We included 184 patients presenting SA-AKI within 6 h of the initiation of catecholamines. Three distinct subphenotypes were identified: subphenotype A (99 patients) was characterized by a normal urine output (UO), a low SCr and a low [TIMP-2]*[IGFBP7] level; subphenotype B (74 patients) was characterized by existing chronic kidney disease (CKD), a higher SCr, a low UO, and an intermediate [TIMP-2]*[IGFBP7] level; and subphenotype C was characterized by very low UO, a very high [TIMP-2]*[IGFBP7] level, and an intermediate SCr level. With subphenotype A as the reference, the adjusted hazard ratio (aHR) [95%CI] for the composite outcome was 3.77 [1.92-7.42] (p < 0.001) for subphenotype B and 4.80 [1.67-13.82] (p = 0.004) for subphenotype C.

CONCLUSIONS

Combining conventional kidney function variables with urine measurements of [TIMP-2]*[IGFBP7] might help to identify distinct SA-AKI subphenotypes with different short-term courses and survival rates.

Novel immune cross-talk between inflammatory bowel disease and IgA nephropathy

The mechanisms underlying the complex correlation between immunoglobulin A nephropathy (IgAN) and inflammatory bowel disease (IBD) remain unclear. This study aimed to identify the optimal cross-talk genes, potential pathways, and mutual immune-infiltrating microenvironments between IBD and IgAN to elucidate the linkage between patients with IBD and IgAN. The IgAN and IBD datasets were obtained from the Gene Expression Omnibus (GEO). Three algorithms, CIBERSORTx, ssGSEA, and xCell, were used to evaluate the similarities in the infiltrating microenvironment between the two diseases. Weighted gene co-expression network analysis (WGCNA) was implemented in the IBD dataset to identify the major immune infiltration modules, and the Boruta algorithm, RFE algorithm, and LASSO regression were applied to filter the cross-talk genes. Next, multiple machine learning models were applied to confirm the optimal cross-talk genes. Finally, the relevant findings were validated using histology and immunohistochemistry analysis of IBD mice. Immune infiltration analysis showed no significant differences between IBD and IgAN samples in most immune cells. The three algorithms identified 10 diagnostic genes, MAPK3, NFKB1, FDX1, EPHX2, SYNPO, KDF1, METTL7A, RIDA, HSDL2, and RIPK2; FDX1 and NFKB1 were enhanced in the kidney of IBD mice. Kyoto Encyclopedia of Genes and Genomes analysis showed 15 mutual pathways between the two diseases, with lipid metabolism playing a vital role in the cross-talk. Our findings offer insights into the shared immune mechanisms of IgAN and IBD. These common pathways, diagnostic cross-talk genes, and cell-mediated abnormal immunity may inform further experimental studies.

adult population: results from the National Health and Nutrition Examination Survey

PURPOSE

Heavy metal exposure can cause impaired or reduced pathology in the kidneys, lungs, liver, and other vital organs. However, the relationship between heavy metal exposure and kidney stones has not been determined. The goal of this research was to determine the association between heavy metal exposure and kidney stones in a population of American adults in general.

MATERIALS AND METHODS

We evaluated 29,201 individuals (≥20 years) from the National Health and Nutrition Examination Survey (NHANES). The association between heavy metal exposure and kidney stones was verified by multiple logistic regression and restricted cubic spline (RCS) regression. Dose-response curves were generated to analyze the relationship between heavy metal concentrations and the occurrence of kidney stones. Moreover, we used propensity score matching (PSM) to exclude the effect of confounding variables.

RESULTS

After a rigorous enrollment screening process, we included 8518 participants. Logistic regression showed that urinary cadmium (U-Cd) and urinary cobalt (U-Co) concentrations were significantly different in the kidney stone group before PSM (p < 0.001). Dose-response curves revealed that the occurrence of kidney stones increased significantly with increasing U-Cd and U-Co concentrations. After adjustment for covariates, only biomarkers of U-Co were linked to the occurrence of kidney stones. When the lowest quartile was used as a reference, the 95% confidence intervals (95% CIs) for kidney stones across the other quartiles were 1.015 (0.767-1.344), 1.409 (1.059-1.875), and 2.013 (1.505-2.693) for U-Cos (p < 0.001).

CONCLUSION

In the U.S. population, high U-Co levels are positively correlated with the potential risk of kidney stones.

Advances in Traditional Chinese Medicine research in diabetic kidney disease treatment

CONTEXT

Diabetic kidney disease (DKD) is a prominent complication arising from diabetic microangiopathy, and its prevalence and renal impact have placed it as the primary cause of end-stage renal disease. Traditional Chinese Medicine (TCM) has the distinct advantage of multifaceted and multilevel therapeutic attributes that show efficacy in improving clinical symptoms, reducing proteinuria, protecting renal function, and slowing DKD progression. Over recent decades, extensive research has explored the mechanisms of TCM for preventing and managing DKD, with substantial studies that endorse the therapeutic benefits of TCM compounds and single agents in the medical intervention of DKD.

OBJECTIVE

This review lays the foundation for future evidence-based research efforts and provide a reference point for DKD investigation.

METHODS

The relevant literature published in Chinese and English up to 30 June 2023, was sourced from PubMed, Cochrane Library, VIP Database for Chinese Technical Periodicals (VIP), Wanfang Data, CNKI, and China Biology Medicine disc (CBM). The process involved examining and summarizing research on TCM laboratory tests and clinical randomized controlled trials for DKD treatment.

RESULTS AND CONCLUSIONS

The TCM intervention has shown the potential to inhibit the expression of inflammatory cytokines and various growth factors, lower blood glucose levels, and significantly affect insulin resistance, lipid metabolism, and improved renal function. Furthermore, the efficacy of TCM can be optimized by tailoring personalized treatment regimens based on the unique profiles of individual patients. We anticipate further rigorous and comprehensive clinical and foundational investigations into the mechanisms underlying the role of TCM in treating DKD.

Cardiovascular and renal safety outcomes of hypoxia-inducible factor prolyl-hydroxylase inhibitor roxadustat for anemia patients with chronic kidney disease: a systematic review and meta-analysis

This systematic review and meta-analysis were conducted to evaluate the cardiac and kidney-related adverse effects of roxadustat for the treatment of anemia in CKD patients. 18 trials with a total of 8806 participants were identified for analysis. We employed a fixed-effects model for analysis. The pooled result revealed no significant difference in the risk of occurrence of cardiac disorders when comparing CKD patients receiving roxadustat with the placebo (RR = 1.049; CI [0.918 to 1.200]) or ESA (RR = 1.066; CI [0.919 to 1.235]), in both dialysis-dependent (DD) (RR = 1.094; CI [0.925 to 1.293]) or non-dialysis-dependent (NDD) (RR = 1.036; CI [0.916 to 1.171]) CKD patients. No significant difference was observed in the risk of kidney-related adverse events when comparing roxadustat with the placebo (RR = 1.088; CI [0.980 to 1.209]) or ESA (RR = 0.968; CI [0.831 to 1.152]), in DD (RR = 2.649; CI [0.201 to 34.981]) or NDD (RR = 1.053; CI [0.965 to 1.149]) CKD patients. A high risk of hyperkalemia was observed in the roxadustat group in DD (RR = 0.939; CI [0.898 to 0.981]). Incidence of hypertension was higher in the roxadustat for NDD patients (RR = 1.198; CI [1.042 to 1.377]), or compared to the placebo (RR = 1.374; CI [1.153 to 1.638]). In summary, the risk of cardiac or kidney-related events observed in the roxadustat was not significantly increase whether in DD or NDD patients. However, attention must be paid to the occurrence of hyperkalemia for DD patients and hypertension in NDD patients using roxadustat.

Elevated ALOX12 in renal tissue predicts progression in diabetic kidney disease

Diabetic kidney disease (DKD) is one of the major causes of end-stage renal disease and one of the significant complications of diabetes. This study aims to identify the main differentially expressed genes in DKD from transcriptome sequencing results and analyze their diagnostic value. The present study sequenced db/m mouse and db/db mouse to determine the ALOX12 genetic changes related to DKD. After preliminary validation, ALOX12 levels were significantly elevated in the blood of DKD patients, but not during disease progression. Moreover, urine ALOX12 was increased only in macroalbuminuria patients. Therefore, to visualize the diagnostic efficacy of ALOX12 on the onset and progression of renal injury in DKD, we collected kidney tissue from patients for immunohistochemical staining. ALOX12 was increased in the kidneys of patients with DKD and was more elevated in macroalbuminuria patients. Clinical chemical and pathological data analysis indicated a correlation between ALOX12 protein expression and renal tubule injury. Further immunofluorescence double staining showed that ALOX12 was expressed in both proximal tubules and distal tubules. Finally, the diagnostic value of the identified gene in the progression of DKD was assessed using receiver operating characteristic (ROC) curve analysis. The area under the curve (AUC) value for ALOX12 in the diagnosis of DKD entering the macroalbuminuria stage was 0.736, suggesting that ALOX12 has good diagnostic efficacy. During the development of DKD, the expression levels of ALOX12 in renal tubules were significantly increased and can be used as one of the predictors of the progression to macroalbuminuria in patients with DKD.

The relationship between kidney disease and mitochondria: a bibliometric study

BACKGROUND

Due to its highly reabsorptive function, the kidney is a mitochondria-dependent organ. Research on the association between mitochondria and kidney disease has always been a serious focus of researchers, with many publications. Bibliometrics is a secondary analysis of published literature that extracts relevant information to gain insights into hotspots and trends in the field. Through bibliometric analysis, we aimed to understand the development trends and hotspots in the field of research on the association between kidney disease and mitochondria.

METHOD

Three bibliometric mapping tools (Biblimetrix R Package, VOS Viewer, CiteSpace) were used to provide an overview of the literature and analyze the co-occurrence of keywords and reference citations.

RESULTS

A total of 2672 relevant research articles were included. The co-occurrence network identified three clusters related to the association between mitochondria and kidney disease, including experimental methods, research mechanisms, and disease phenotypes. We found that research in this field has shifted from disease-level studies to mechanism-based studies, with the most prominent disease being diabetic nephropathy and the most prominent pathogenic mechanism being related to mitochondrial ROS production.

CONCLUSION

The bibliometric analysis provided a comprehensive understanding of the progress of research on the role of mitochondria in kidney disease, enriching the review literature in this field.

Association between the levels of urinary cell cycle biomarkers and non-recovery of renal function among critically ill geriatric patients with acute kidney injury

The lack of early renal function recovery among geriatric patients with acute kidney injury (AKI) in the intensive care unit (ICU) is a commonly observed and acknowledged poor prognostic factor, especially for older adults. However, no reliable prognostic biomarker is available for identifying individuals at risk of renal non-recovery or mortality in older adults. In this prospective observational cohort study, we enrolled critically ill older adults (aged ≥ 60 years) with AKI from the ICU and followed their disease progression. The primary endpoint was renal non-recovery within seven days of follow-up, while the secondary endpoint was the determinants of 30-day mortality after AKI. We assessed the predictive accuracy using receiver operating characteristic curves and performed between-group comparisons using the log-rank test. Among 209 older adults, 117 (56.0%) experienced renal recovery. Multiple regression analysis revealed that urine levels of tissue inhibitor of metalloproteinase-2 (TIMP-2) multiplied by insulin-like growth factor-binding protein 7 (IGFBP7) ([TIMP-2]*[IGFBP7]), AKI stages 2-3, and the Acute Physiology and Chronic Health Evaluation (APACHE II) score were independently associated with renal non-recovery. The regression model incorporating [TIMP-2]*[IGFBP7] demonstrated a fair predictive value (AUC 0.774, p < 0.001), with the optimal threshold set at 0.81 (ng/mL)2/1000. When [TIMP-2]*[IGFBP7] was combined with AKI severity and the APACHE score, the AUC increased to 0.851. In conclusion, urine [TIMP-2]*[IGFBP7] is a reliable biomarker associated with renal non-recovery in critically ill older adults, and its predictive efficacy can be further enhanced when combined with AKI severity and the APACHE score.

Recent advances in the application of Mendelian randomization to chronic kidney disease

OBJECTIVE

Chronic kidney disease (CKD) is a condition influenced by both genetic and environmental factors and has been a focus of extensive research. Utilizing Mendelian randomization, researchers have begun to untangle the complex causal relationships underlying CKD. This review delves into the advances and challenges in the application of MR in the field of nephrology, shifting from a mere summary of its principles and limitations to a more nuanced exploration of its contributions to our understanding of CKD.

METHODS

Key findings from recent studies have been pivotal in reshaping our comprehension of CKD. Notably, evidence indicates that elevated testosterone levels may impair renal function, while higher sex hormone-binding globulin (SHBG) levels appear to be protective, predominantly in men. Surprisingly, variations in plasma glucose and glycated hemoglobin levels seem unaffected by genetically induced changes in the estimated glomerular filtration rate (eGFR), suggesting an independent pathway for renal function impairment.

RESULTS

Furthermore, lifestyle factors such as physical activity and socioeconomic status emerge as significant influencers of CKD risk and kidney health. The relationship between sleep duration and CKD is nuanced; short sleep duration is linked to increased risk, while long sleep duration does not exhibit a clear causal effect. Additionally, lifestyle factors, including diet, exercise, and mental wellness activities, play a crucial role in kidney health. New insights also reveal a substantial causal connection between both central and general obesity and CKD onset, while no significant links were found between genetically modified LDL cholesterol or triglyceride levels and kidney function.

CONCLUSION

This review not only presents the recent achievements of MR in CKD research but also illuminates the path forwards, underscoring critical unanswered questions and proposing future research directions in this dynamic field.

A phenylalanine at the extracellular side of Kir1.1 facilitates potassium permeation

The Kir1.1 (ROMK) family of weak inward rectifiers controls K secretion in the renal CCT and K recycling in the renal TALH. A single point mutant of the inward rectifier, F127V-Kir1.1b was used to investigate the K transition between the selectivity filter and the outer mouth of the channel. We hypothesize that normally an aromatic Phe at the external entryway of Kir1.1b facilitates outward K secretion. We tested this by replacing F127-Kir1.1b with a small aliphatic Val. Results indicate that removal of the Phe at 127 suppresses outward currents that normally contribute to K secretion. Results with the F127V mutant could be explained by increased polyamine block and/or a decrease in the avidity of Kir1.1 for K ions near the outer mouth of the channel. The latter is supported by F127V-Kir1.1b having a lower affinity (Km = 33 mM) for K than wild-type Kir1.1b (Km = 7 mM) during external K elevation. Conversely, chelation of K with 18-Crown-6 ether reduced K conductance faster in F127V (half-time = 6s) than in wt-Kir1.1b (half-time = 120s), implying that F127V is less hospitable to external K. In other experiments, positive membrane potentials gated the F127V mutant channel closed at physiological levels of external Ca, possibly by electrostatically depleting K adjacent to the membrane, suggesting that the Phe residue is critical for outward K secretion at physiological Ca. We speculate that the avidity of wt-Kir1.1b for external K could result from a cation-Pi interaction between K and the aromatic F127.

Tiny clue reveals the general trend: a bibliometric and visualized analysis of renal microcirculation

BACKGROUND

Renal microcirculation plays a pivotal role in kidney function by maintaining structural and functional integrity, facilitating oxygen and nutrient delivery, and waste removal. However, a thorough bibliometric analysis in this area remains lacking. Therefore, we aim to provide valuable insights through a bibliometric analysis of renal microcirculation literature using the Web of Science database.

METHODS

We collected renal microcirculation-related publications from the Web of Science database from January 01, 1990, to December 31, 2022. The co-authorship of authors, organizations, and countries/regions was analyzed with VOSviewer1.6.18. The co-occurrence of keywords and co-cited references were analyzed using CiteSpace6.1.R6 software to generate visualization maps. Additionally, burst detection was applied to keywords and cited references to forecast research hotspots and future trends.

RESULTS

Our search yielded 7462 publications, with the American Journal of Physiology-Renal Physiology contributing the most articles. The United States, Mayo Clinic, and Lerman Lilach O emerged with the highest publication count, indicating their active collaborations. 'Type 2 diabetes' was the most significant keyword cluster, and 'diabetic kidney disease' was the largest cluster of cited references. 'Cardiovascular outcome' and 'diabetic kidney diseases' were identified as keywords in their burst period over the past three years.

CONCLUSION

Our bibliometric analysis illuminates the contours of nephrology and microcirculation research, revealing a landscape ripe for challenges and the seeds of future scientific innovation. While the trends discerned from the literature emerging opportunities in diagnostic innovation, renal microcirculation research, and precision medicine interventions, their translation to clinical practice is anticipated to be a deliberate process.

COVID-19 and renal allograft rejection: insight from controlled and non-controlled studies

AIM

Kidney transplant recipients (KTRs), due to their immunosuppressed status, are potentially more susceptible to both the severe effects of COVID-19 and complications in their transplanted organ. The aim of this study is to investigate whether COVID-19 infection increases the risk of rejection in kidney transplant recipients (KTRs).

METHODS

This study involved a detailed literature review, conducted using PubMed, with the search being completed by September 7th, 2023. The search strategy incorporated a combination of relevant keywords: 'COVID', 'Renal', 'Kidney', 'Transplant', and 'Rejection'. The results from controlled and uncontrolled studies were separately collated and analyzed.

RESULTS

A total of 11 studies were identified, encompassing 1,179 patients. Among these, two controlled studies reported the incidence of rejection in KTRs infected with COVID-19. Pooling data from these studies revealed no significant statistical correlation between COVID-19 infection and biopsy-proven rejection (p = 0.26). In addition, nine non-controlled studies were found, with rejection incidences ranging from 0% to 66.7%. The majority of these studies (eight out of nine) had small sample sizes, ranging from 3 to 75 KTRs, while the largest included 372 KTRs. The combined rejection rate across these studies was calculated to be 11.8%.

CONCLUSION

In conclusion, the limited number of published controlled studies revealed no statistically significant association between COVID-19 infection and biopsy-proven rejection among KTRs. However, the broader analysis of non-controlled studies showed a variable rejection incidence with a pooled rejection rate of 11.8%. There is insufficient high-quality data to explore the association of COVID-19 infection and rejection.

A Mendelian randomization study: physical activities and chronic kidney disease

Increasing evidence has shown that physical activity is related to a lower risk of chronic kidney disease (CKD), thus indicating a potential target for prevention. However, the causality is not clear; specifically, physical activity may protect against CKD, and CKD may lead to a reduction in physical activity. Our study examined the potential bidirectional relationship between physical activity and CKD by using a genetically informed method. Genome-wide association studies from the UK Biobank baseline data were used for physical activity phenotypes and included 460,376 participants. For kidney function (estimated Glomerular Filtration Rate (eGFR) and CKD, with eGFR < 60 mL/min/1.73 m2), CKDGen Consortium data were used, which included 480,698 CKD participants of European ancestry. Mendelian randomization (MR) analysis was used to determine the causal relationship between physical activities and kidney function. Two-sample MR genetically predicted that heavy DIY (do it yourself) (e.g., weeding, lawn mowing, carpentry, and digging) decreased the risk of CKD (odds ratio [OR] = 0.287, 95% CI = 0.117-0.705, p = 0.0065) and improved the level of eGFR (β = 0.036, 95% CI = 0.005-0.067, p = 0.021). The bidirectional MR showed no reverse causality. It is worth noting that other physical activities, such as walking for pleasure, strenuous sports, light DIY (e.g., pruning and watering the lawn), and other exercises (e.g., swimming, cycling, keeping fit, and bowling), were not significantly correlated with CKD and eGFR. This study used genetic data to provide reliable and robust causal evidence that heavy physical activity (e.g., weeding, lawn mowing, carpentry, and digging) can protect kidney function and further lower the risk of CKD.

Acute kidney injury in patients treated with immune checkpoint inhibitors: a single-center retrospective study

BACKGROUND

Immune checkpoint inhibitor-associated acute kidney injury (ICI-AKI) is the most common renal complication and has attracted increasing amounts of attention. However, studies on this topic in Chinese cancer patients are very limited. Therefore, we conducted a retrospective study on the incidence, risk factors, clinical features and renal recovery of ICI-AKI in all patients with malignancies treated with ICIs in Shandong Provincial Hospital Affiliated to Shandong First Medical University.

METHODS

In this single-center retrospective cohort study, the data of 904 patients who received immune checkpoint inhibitors (ICIs) treatment were retrospectively analyzed. Multivariable logistic regression was used to identify the predictors of ICI-AKI.

RESULTS

A total of 46 of 904 patients receiving ICIs developed ICI-AKI, and the incidence of ICI-AKI was 5.1%. Patients developed ICI-AKI at a median of 9 weeks (IQR 3-23) after ICIs initiation. A lower baseline estimated glomerular filtration rate (eGFR) and use of antibiotics were associated with a higher risk of ICI-AKI. Renal recovery occurred in 17 patients (46%) at a median of 4 weeks (IQR 2-8) after ICI-AKI, including 16 (43%) with complete recovery and 1 (3%) with partial recovery. Of the 14 rechallenged patients, only one developed recurrent ICI-AKI.

CONCLUSIONS

Patients with ICI-AKI were more likely to have impaired renal function at baseline and after treatment with antibiotics. Approximately half of the patients achieved renal recovery.

Novel biomarkers in patients with uncontrolled hypertension with and without kidney damage

INTRODUCTION

Estimated glomerular filtration rate (eGFR) and urine albumin/creatinine ratio (ACR) are insensitive biomarkers for early detection of hypertension-mediated organ damage (HMOD). In this nationwide cross-sectional study, we assessed potential biomarkers for early HMOD in healthy persons and patients with hypertension. We hypothesised that plasma levels of biomarkers: (1) are different between healthy controls and patients with hypertension, (2): can classify patients with hypertension according to the degree of hypertension severity.

DESIGN AND METHODS

Patients with hypertension prescribed ≥2 antihypertensive agents were selected from a multicentre study. Healthy controls were selected from an ongoing study of living kidney donor candidates. Uncontrolled hypertension was defined as systolic daytime ambulatory blood pressure ≥135 mmHg. Kidney HMOD was defined by ACR > 3.0 mg/mmol or eGFR < 60 mL/min/1.73 m2. Patients with hypertension were categorised into three groups: (1) controlled hypertension; (2) uncontrolled hypertension without kidney HMOD; (3) uncontrolled hypertension with kidney HMOD. Fifteen biomarkers were analysed using a Luminex bead-based immunoassay, and nine fell within the specified analytical range.

RESULTS

Plasma levels of Interleukin 1 receptor antagonist (IL-1RA), neutrophil gelatinase-associated lipocalin (NGAL) and uromodulin were significantly different between healthy controls (n = 39) and patients with hypertension (n = 176). In regression models, with controlled hypertension (n = 55) as the reference category, none of the biomarkers were associated with uncontrolled hypertension without (n = 59) and with (n = 62) kidney HMOD. In models adjusted for cardiovascular risk factors and eGFR, osteopontin (OPN) was associated with uncontrolled hypertension without kidney HMOD (odds ratio (OR) 1.77 (1.05-2.98), p = 0.03), and regulated upon activation normal T-cell expressed and secreted (RANTES) with uncontrolled hypertension with kidney HMOD (OR 0.57 (0.34-0.95), p = 0.03).

CONCLUSIONS

None of the biomarkers could differentiate our hypertension groups when established risk factors were considered. Plasma OPN may identify patients with uncontrolled hypertension at risk for kidney HMOD.

The relationship between dietary inflammatory index (DII) and early renal injury in population with/without hypertension: analysis of the National health and nutrition examination survey 2001-2002

BACKGROUND

Inflammation plays a crucial role in occurrence of kidney injury, and specific dietary patterns can influence systemic inflammation levels. However, the relationship between dietary inflammatory potential and early-stage kidney damage remains unclear.

METHOD

2,108 participants was recruited from 2001-2002 National Health and Nutrition Examination Survey (NHANES). Dietary Inflammatory Index (DII) is utilized to assess dietary inflammatory potential, calculated through a 24-h dietary recall questionnaire. Early renal injury was evaluated using urinary albumin to creatinine (UACR), cystatin C (CysC), β-2 microglobulin (β2M), and estimated glomerular filtration rate (eGFR) based on serum creatinine (eGFRs), cystatin C (eGFRc), and both Scr and CysC (eGFRs&c). Participant characteristics were analyzed, and association between DII, hypertension, and early renal injury markers was explored using multiple linear and logistic regression models.

RESULTS

The average age of participants was 53.9 years. DII exhibited a positive correlation with UACR (β = -0.048[0.017,0.078]), β2M (β = 0.019[0.010,0.027]), CysC (β = 0.012 [0.004,0.021]). Conversely, a negative correlation was observed between DII and eGFRc (β = -1.126[-1.554, -0.699]), eGFRs&c (β=-1.101[-1.653, -0.549]). A significant association was observed between hypertension and abnormality of early kidney damage markers. Subgroup analysis reveals that the positive correlation between DII and the occurrence of abnormal markers of early kidney damage is only observed in individuals with hypertension. Furthermore, an interaction between DII and hypertension was detected in eGFRs&c (OR:1.250[1.042, 1.499], p for interaction = 0.03).

CONCLUSION

Higher levels of DII may be associated with occurrence of early kidney damage. For individuals with hypertension, avoiding excessive consumption of pro-inflammatory foods may reduce the risk of renal injury.

Therapeutic effects of acupuncture therapy for kidney function and common symptoms in patients with chronic kidney disease: a systematic review and meta-analysis

Purpose: The number of clinical reports of acupuncture therapy in chronic kidney disease (CKD) is gradually increasing. This systematic review and meta-analysis aim to examine the therapeutic role of acupuncture therapy in kidney function and common symptoms in CKD patients.Methods: We searched Embase, PubMed, Scopus, Web of Science, China National Knowledge Infrastructure, WanFang, and WeiPu for randomized controlled trials comparing acupuncture treatment with control or placebo groups. We assessed the effect of acupuncture therapy in CKD patients using a meta-analysis with the hartung-knapp-sidik-jonkman random effects model. In addition, we visualized keyword co-occurrence overlay visualization with the help of VOSviewer software to describe the research hotspots of acupuncture therapy and CKD.Results: A total of 24 studies involving 1494 participants were included. Compared to the control group, acupuncture therapy reduced serum creatinine levels (standardized mean difference [SMD]: -0.57; 95% CI -1.05 to -0.09) and relieved pruritus (SMD: -2.20; 95% CI -3.84, -0.57) in patients with CKD, while the TSA showed that the included sample size did not exceed the required information size. The included studies did not report acupuncture-related adverse events.Conclusions: Acupuncture is an effective and safe treatment for improving kidney function and relieving pruritic symptoms in patients with CKD, but the very low evidence may limit this conclusion. The TSA suggests that high-quality trials are needed to validate the efficacy of acupuncture therapy.

The association between bone density of lumbar spines and different daily protein intake in different renal function

BACKGROUND

Low protein intake (LPI) has been suggested as a treatment for chronic kidney disease (CKD). However, protein intake is essential for bone health.

METHODS

We studied the database of the National Health and Nutrition Examination Survey, 2005-2010. Basic variables, metabolic diseases, and bone density of different femoral areas were stratified into four subgroups according to different protein intake (DPI) (that is, <0.8, 0.8-1.0, 1.0-1.2, and >1.2 g/kg/day).

RESULTS

Significant differences were found among all lumbar area bone mineral density (BMD) and T-scores (p < 0.0001). There was an apparent trend between a decreasing BMD in the CKD groups with increasing DPI in all single lumbar spines (L1, L2, L3, and L4) and all L spines (L1-L4). Compared with DPI (0.8-1.0 g/day/kg), higher risks of osteoporosis were noticed in the subgroup of >1.2 g/day/kg over L2 (relative risk (RR)=1.326, 95% confidence interval (CI)=1.062-1.656), subgroup >1.2 g/day/kg over L3 (RR = 1.31, 95%CI = 1.057-1.622), subgroup <0.8 g/day/kg over L4 (RR = 1.276, 95%CI = 1.015-1.605), subgroup <0.8 g/day/kg over all L spines (RR = 11.275, 95%CI = 1.051-1.548), and subgroup >1.2 g/day/kg over all L spines (RR = 0.333, 95%CI = 1.098-1.618). However, a higher risk of osteoporosis was observed only in the non-CKD group. There was an apparent trend of higher DPI coexisting with lower BMD and T scores in patients with CKD. For osteoporosis (reference:0.8-1.0 g/day/kg), lower (<0.8 g/day/kg) or higher DPI (>1.2 g/day/kg) was associated with higher risks in the non-CKD group, but not in the CKD group.

CONCLUSIONS

In the CKD group, LPI for renal protection was safe without threatening L spine bone density and without causing a higher risk of osteoporosis.

Intra-abdominal pressure and residual renal function decline in peritoneal dialysis: a threshold-based investigation

BACKGROUND

The potential impact of elevated intra-abdominal pressure (IAP) on residual renal function (RRF) has not been determined. The objective of this study was to investigate the relationship between IAP and the rate of RRF decline in newly initiated peritoneal dialysis (PD) patients, and to identify the optimal IAP threshold value for delaying the deterioration of RRF.

METHODS

A cohort of 62 newly initiated PD patients who completed both 6- and 12-month follow-up evaluations was obtained using the Durand method. A logistic regression model was used to identify variables associated with a rapid decline in RRF. Receiver operating characteristic (ROC) curves were generated to determine the optimal threshold value. Another retrospective cohort analysis was performed to validate the identified critical value.

RESULTS

For each 1 cmH2O increase in IAP, the risk of a rapid decline in the RRF increased by a factor of 1.679. Subsequent analysis revealed that patients in the high IAP group had more significant decreases in residual renal estimated glomerular filtration rate (eGFR) (Z = -3.694, p < 0.001) and urine volume (Z = -3.121, p < 0.001) than did those in the non-high IAP group. Furthermore, an IAP ≥15.65 cmH2O was a robust discriminator for the prediction of the rate of RRF decline.

CONCLUSION

Patients in the high IAP group experienced a more rapid decline in RRF. Additionally, an optimal critical pressure of 15.65 cmH2O was identified for predicting the rate of RRF decline. IAP, as one of the factors contributing to the rapid decline in RRF in the first year of PD, should be given due attention.

Gut microbiota in the association between obesity and kidney function decline: a metagenomics-based study in a rat model

OBJECTIVES

Obesity can induce dysbiosis in the gut microbiota and is considered a separate risk factor for kidney function decline. Nonetheless, the precise function of intestinal microorganisms in facilitating the connection between obesity and kidney function decline remains uncertain. Hence, the objective of this study was to investigate the alterations in the gut microbiota composition that take place during obesity and their correlations with renal function utilizing a rat model.

METHODS

For 20 weeks, 25 Sprague-Dawley rats were fed either a high-fat diet (HFD) or a normal-fat normal diet (ND). Physiological indices, peripheral plasma, kidney tissue, and colon contents were collected for comparison between groups. Metagenomic analysis of intestinal flora was performed.

RESULTS

The HFD group demonstrated significantly increased levels of creatinine and urea nitrogen in the peripheral blood. Additionally, the HFD rats exhibited a significantly larger glomerular diameter compared to the ND group, accompanied by the presence of glomerulosclerosis, tubular vacuolar transformation, and other pathological changes in certain glomeruli. Metagenomics analysis revealed a notable rise in the prevalence of the Firmicutes phylum within the HFD group, primarily comprising the Rumenococcus genus. Functional analysis indicated that the gut microbiota in the HFD group primarily correlated with infectious diseases, signal transduction, and signaling molecules and interactions.

CONCLUSIONS

This study provides evidence that the consumption of a HFD induces modifications in the composition and functionality of the gut microbiome in rats, which may serve as a potential mechanism underlying the relationship between obesity and the progression of kidney function decline.

Chronic kidney disease and orthostatic hypotension in hospitalised older adults

PURPOSE

Orthostatic hypotension (OH) may predispose older adults to health complications leading to functional impairment. Despite the central role of the kidney in blood pressure control, the contribution of renal function in orthostatic hypotension is poorly investigated. To verify the association between Chronic Kidney Disease (CKD) and OH a population of hospitalised elderly patients with comorbidities was studied.

MATERIALS AND METHODS

174 patients were consecutively admitted to Acute Geriatric Wards. On admission, patients underwent postural systolic (SBP) and diastolic (DBP) blood pressure evaluation by automatic oscillometric device after 10 min rest in lying position, and in standing position at time 0, 1, 3 and 5 min. CKD was assumed for estimated glomerular filtration rate (e-GFR) less than 60 mL/min/1.73 m2.

RESULTS

The mean age of the population enrolled was 74.4 ± 7.0. OH was found in 46.0% and CKD in 56.3% of patients, respectively. A lower e-GFR was observed in patients with (56.1 ± 16.7 mL/min/1.73 m2) than in those without OH (61.1 ± 15.9 mL/min/1.73 m2) (p < 0.05). A greater fall in SBP at 0-min (12.8 ± 6.3 vs. 7.7 ± 3.2 mmHg) and at 1-min (8.4 ± 4.5 vs. 5.7 ± 2.8 mmHg) was found in CKD patients in respect to patients without CKD during active standing test (p < 0.05). Similarly, a DBP reduction at 0-min and at 1-min was observed in CKD patients in respect to patients without CKD (p < 0.05). A multivariate logistic regression analysis showed that CKD was associated to OH (OR 2.426; 95%CI 1.192-4.937; p = 0.014).

CONCLUSIONS

CKD is associated to OH in hospitalised older adults.

Shen Shuai II recipe improves renal hypoxia to attenuate renal injury in 5/6 renal ablation/infarction rats and effect evaluation using blood oxygenation level-dependent functional magnetic resonance imaging

Background: Renal hypoxia plays a key role in the progression of chronic kidney disease (CKD). Shen Shuai II Recipe (SSR) has shown good results in the treatment of CKD as a common herbal formula. This study aimed to explore the effect of SSR on renal hypoxia and injury in CKD rats. Methods: Twenty-five Wistar rats underwent 5/6 renal ablation/infarction (A/I) surgery were randomly divided into three groups: 5/6 (A/I), 5/6 (A/I) + losartan (LOS), and 5/6 (A/I) + SSR groups. Another eight normal rats were used as the Sham group. After 8-week corresponding interventions, blood oxygenation level-dependent functional magnetic resonance imaging (BOLD-fMRI) was performed to evaluate renal oxygenation in all rats, and biochemical indicators were used to measure kidney and liver function, hemoglobin, and proteinuria. The expression of fibrosis and hypoxia-related proteins was analyzed using immunoblotting examination. Results: Renal oxygenation, evaluated by BOLD-fMRI as cortical and medullary T2* values (COT2* and MET2*), was decreased in 5/6 (A/I) rats, but increased after SSR treatment. SSR also downregulated the expression of hypoxia-inducible factor-1α (HIF-1α) in 5/6 (A/I) kidneys. With the improvement of renal hypoxia, renal function and fibrosis were improved in 5/6 (A/I) rats, accompanied by reduced proteinuria. Furthermore, the COT2* and MET2* were significantly positively correlated with the levels of creatinine clearance rate (Ccr) and hemoglobin, but negatively associated with the levels of serum creatinine (SCr), blood urea nitrogen (BUN), serum cystatin C (CysC), serum uric acid (UA), 24-h urinary protein (24-h Upr), and urinary albumin:creatinine ratio (UACR). Conclusion: The degree of renal oxygenation reduction is correlated with the severity of renal injury in CKD. SSR can improve renal hypoxia to attenuate renal injury in 5/6 (A/I) rats of CKD.

The acute toxic effect of Chinese medicine Fuzi is exacerbated in kidney yang deficiency mice due to metabolic difference

ETHNOPHARMACOLOGICAL RELEVANCE

The proper application of toxic medicines is one of the characteristics of traditional Chinese medicines, and the use of traditional Chinese medicines follows the principle of dialectical treatment. It is necessary to combine different "syndrome" or "disease" states with the toxicity of traditional Chinese medicines to form a reliable toxicity evaluation system. Fuzi, the lateral root of Aconitum carmichaelii Debx, is recognized as a panacea for kidney yang deficiency syndrome, however, its toxic effects significantly limit its clinical application.

AIM OF THE STUDY

Herein, our research aimed to explore the toxic effects of Fuzi on syndrome models, and tried to reveal the underlying mechanisms.

MATERIALS AND METHODS

Firstly, the mouse model of kidney yang deficiency syndrome was established through intramuscular injection of 25 mg/kg hydrocortisone per day for 10 consecutive days. Then, the acute toxicity of Fuzi in normal mice and kidney yang deficiency model mice was explored. Finally, the plasma metabolite concentrations and liver CYP3A4 enzyme activity were analyzed to reveal the possible mechanisms of the different pharmacological and toxicological effects of Fuzi in individuals with different physical constitutions.

RESULTS

It was found that the treatment with Fuzi (138 g/kg) had serious toxic effects on kidney yang deficiency mice, leading to the death of 80% of the mice, whereas it showed no lethal toxicity in normal mice. This indicates that Fuzi induced greater toxicity in kidney yang deficiency mice than in normal ones. The liver CYP3A4 enzyme activity in kidney yang deficiency mice was decreased by 20% compared to the controls, resulting in slower metabolism of the toxic diester diterpenoid alkaloids in Fuzi.

CONCLUSION

In conclusion, our study showed that changes of the metabolic enzyme activity in individuals with different syndromes led to different toxic effects of Chinese medicines, emphasizing the crucial importance of considering individual physical syndromes in the clinical application of traditional Chinese medicine, and the significance of conducting safety evaluations and dose predictions on animal models with specific syndromes for traditional Chinese medicines.

Treatment of diabetic retinopathy with herbs for tonifying kidney and activating blood circulation: A review of pharmacological studies

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetic retinopathy (DR) is a prevalent microvascular complication of diabetes. Chinese medicine believes that kidney deficiency and blood stasis are significant pathogenesis of DR. A characteristic therapeutic approach for this pathogenesis is the kidney-tonifying and blood-activating method. By literature retrieval from several databases, we methodically summarized the commonly used kidney-tonifying and blood-activating herbs for treating DR, including Lycii Fructus, Rehmanniane Radix Praeparata, and Corni Fructus with the function of nourishing kidney; Salvia Miltiorrhizae Radix et Rhizoma with the function of enhancing blood circulation; Rehmanniae Radix with the function of nourishing kidney yin; and Astragali Radix with the function of tonifying qi. It has been demonstrated that these Chinese herbs described above, by tonifying the kidney and activating blood circulation, significantly improve the course of DR.

AIM OF THE STUDY

Through literature research, to gain a thorough comprehension of the pathogenesis of DR. Simultaneously, through the traditional application analysis, modern pharmacology research and network pharmacology analysis of kidney-tonifying and blood-activating herbs, to review the effectiveness and advantages of kidney-tonifying and blood-activating herbs in treating DR comprehensively.

MATERIALS AND METHODS

PubMed, the China National Knowledge Infrastructure (CNKI), and Wanfang Data were used to filter the most popular herbs for tonifying kidney and activating blood in the treatment of DR. The search terms were "diabetic retinopathy" and "tonifying kidney and activating blood". Mostly from 2000 to 2023. Network pharmacology was applied to examine the key active components and forecast the mechanisms of kidney-tonifying and blood-activating herbs in the treatment of DR.

RESULTS

Kidney deficiency and blood stasis are the pathogenesis of DR, and the pathogenesis is linked to oxidative stress, inflammation, hypoxia, and hyperglycemia. Scientific data and network pharmacology analysis have demonstrated the benefit of tonifying kidney and activating blood herbs in treating DR through several channels, multiple components, and multiple targets.

CONCLUSIONS

This review first presents useful information for subsequent research into the material foundation and pharmacodynamics of herbs for tonifying kidney and activating blood, and offers fresh insights into the treatment of DR.

Demethylzeylasteral protects against renal interstitial fibrosis by attenuating mitochondrial complex I-mediated oxidative stress

ETHNOPHARMACOLOGICAL RELEVANCE

Renal interstitial fibrosis (RIF) is a main pathological process in chronic kidney disease (CKD). Demethylzeylasteral (DML), a major component of Tripterygium wilfordii Hook. f., has anti-renal fibrosis effects. However, its mechanism of action remains incompletely understood.

AIM OF THE STUDY

The present study was designed to comprehensively examine the effects of DML on RIF and the underlying mechanisms.

MATERIALS AND METHODS

Pathological experiments were performed to determine the therapeutic effect of DML on a mouse model of UUO-induced RIF. To determine the novel mechanisms underlying the therapeutic effects of DML against RIF, a comprehensive transcriptomics analysis was performed on renal tissues, which was further verified by a series of experiments.

RESULTS

Pathological and immunohistochemical staining showed that DML inhibited UUO-induced renal damage and reduced the expression of fibrosis-related proteins in mice. Transcriptomic analysis revealed that the partial subunits of mitochondrial complex (MC) I and II may be targets by which DML protects against RIF. Furthermore, DML treatment reduced mitochondrial reactive oxygen species (ROS) levels, consequently promoting ATP production and mitigating oxidative stress-induced injury in mice and cells. Notably, this protective effect was attributed to the inhibition of MC I activity, suggesting a crucial role for this specific complex in mediating the therapeutic effects of DML against RIF.

CONCLUSIONS

This study provides compelling evidence that DML may be used to treat RIF by effectively suppressing mitochondrial oxidative stress injury mediated by MC I. These findings offer valuable insights into the pharmacological mechanisms of DML and its potential clinical application for patients with CKD.

Xanthoceras sorbifolium leaves alleviate hyperuricemic nephropathy by inhibiting the PI3K/AKT signaling pathway to regulate uric acid transport

ETHNOPHARMACOLOGICAL RELEVANCE

In China, Xanthoceras sorbifolium Bunge was first documented as "Wen Guan Hua" in the "Jiu Huang Ben Cao" in 1406 A.D. According to the "National Compilation of Chinese Herbal Medicine," X. sorbifolium leaves are sweet and flat in nature and can dispel wind and dampness, suggesting that their extract can be used to treat rheumatoid arthritis. X. sorbifolium Bunge has also been used to treat arteriosclerosis, hyperlipidemia, hypertension, chronic hepatitis, and rheumatism, complications associated with hyperuricemic nephropathy (HN), a condition characterized by kidney damage resulting from high levels of uric acid (UA) in the blood.

AIM OF THE STUDY

The purpose of this study was to investigate the effects and underlying mechanisms of a 70% ethanol extract from X. sorbifolium leaves (EX) in alleviating HN.

MATERIALS AND METHODS

A mouse model of hyperuricemia was established to initially evaluate the hypouricemic effects and determine the effective dose of EX. Phytochemical analyses were conducted using ultra high-performance liquid chromatography and liquid chromatography-mass spectroscopy. The potential key pathways of EX in the alleviation of HN were inferred using network pharmacology and bioinformatics. An HN rat model was then established, and experiments including biomarker detection, western blotting, reverse transcription quantitative polymerase chain reaction, immunohistochemical and Masson's trichrome staining, and transmission electron microscopy were conducted to evaluate the effect of EX on UA transporter expression in vitro.

RESULTS

Network pharmacology and bioinformatics analyses revealed that the phosphoinositide 3-kinase (PI3K)/AKT signaling pathway was the key pathway for the alleviation of HN progression by EX. EX treatment reduced serum biomarkers in HN rats, downregulated the expression of p-PI3K, p-AKT, glucose transporter 9 (GLUT9), urate transporter 1 (URAT1), Collagen I, matrix metalloproteinase (MMP)-2, and MMP-9, and upregulated the expression of ATP binding cassette subfamily G member 2 (ABCG2) to improve renal interstitial fibrosis in HN rats. A high content of both quercitrin and cynaroside were identified in EX; their administration inhibited the increased expression of GLUT9 and URAT1 in damaged HK-2 cells.

CONCLUSION

Our study provides evidence that EX alleviates HN. The potential mechanism underlying this effect may be the regulation of UA transporters, such as GLUT9 and URAT1, by limiting the activation of the PI3K/AKT signaling pathway to improve renal injury.

Prevalence and risk factors for impaired renal function among Asian patients with nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is associated with impaired renal function, and both diseases often occur alongside other metabolic disorders. However, the prevalence and risk factors for impaired renal function in patients with NAFLD remain unclear. The objective of this study was to identify the prevalence and risk factors for renal impairment in NAFLD patients.

METHODS

All adults aged 18-70 years with ultrasound-diagnosed NAFLD and transient elastography examination from eight Asian centers were enrolled in this prospective study. Liver fibrosis and cirrhosis were assessed by FibroScan-aspartate aminotransferase (FAST), Agile 3+ and Agile 4 scores. Impaired renal function and chronic kidney disease (CKD) were defined by an estimated glomerular filtration rate (eGFR) with value of < 90 mL/min/1.73 m2 and < 60 mL/min/1.73 m2, respectively, as estimated by the CKD-Epidemiology Collaboration (CKD-EPI) equation.

RESULTS

Among 529 included NAFLD patients, the prevalence rates of impaired renal function and CKD were 37.4% and 4.9%, respectively. In multivariate analysis, a moderate-high risk of advanced liver fibrosis and cirrhosis according to Agile 3+ and Agile 4 scores were independent risk factors for CKD (P< 0.05). Furthermore, increased fasting plasma glucose (FPG) and blood pressure were significantly associated with impaired renal function after controlling for the other components of metabolic syndrome (P< 0.05). Compared with patients with normoglycemia, those with prediabetes [FPG ≥ 5.6 mmol/L or hemoglobin A1c (HbA1c) ≥ 5.7%] were more likely to have impaired renal function (P< 0.05).

CONCLUSIONS

Agile 3+ and Agile 4 are reliable for identifying NAFLD patients with high risk of CKD. Early glycemic control in the prediabetic stage might have a potential renoprotective role in these patients.

Plasma sodium during the recovery of renal function in critically ill adult patients: Multicenter prospective cohort study

BACKGROUND

Sodium increases during acute kidney injury (AKI) recovery. Both hypernatremia and positive fluid balances are associated with increased mortality. We aimed to evaluate the association between daily fluid balance and daily plasma sodium during the recovery from AKI among critical patients.

METHODS

Adult patients with AKI were enrolled in four ICUs and followed up for four days or until ICU discharge or hemodialysis initiation. Day zero was the peak day of creatinine. The primary outcome was daily plasma sodium; the main exposure was daily fluid balance.

RESULTS

93 patients were included. The median age was 66 years; 68% were male. Plasma sodium increased in 79 patients (85%), and 52% presented hypernatremia. We found no effect of daily fluid balance on plasma sodium (β -0.26, IC95%: -0.63-0.13; p = 0.19). A higher total sodium variation was observed in patients with lower initial plasma sodium (β -0.40, IC95%: -0.53 to -0.27; p < 0.01), higher initial urea (β 0.07, IC95%: 0.04-0.01; p < 0.01), and higher net sodium balance (β 0.002, IC95%: 0.0001-0.01; p = 0.05).

CONCLUSIONS

The increase in plasma sodium is common during AKI recovery and can only partially be attributed to the water and electrolyte balances. The incidence of hypernatremia in this population of patients is higher than in the general critically ill patient population.

Use of a donor kidney with known autosomal dominant polycystic kidney disease in a highly sensitised paediatric recipient

We report the use of an autosomal-dominant polycystic kidney disease (ADPKD) donor kidney in a paediatric recipient. A 14-year-old boy on haemodialysis for 4 years following loss of a first kidney transplant, highly sensitised, and with limited vascular options for ongoing dialysis access, was offered a deceased brain death donor transplant from a mid-30s donor with known ADPKD but normal kidney function and negligible proteinuria. After extensive discussion with the patient and family, discussing all alternative options and review of available literature, the kidney was accepted and implanted. Graft function was immediate. An early post-transplant creatinine rise was attributed to possible antibody-mediated rejection, treated with plasmapheresis and rituximab. Ten months post-transplant, the patient remains dialysis-free with stable function. Extended criteria kidneys are already considered for highly sensitised or long-waiting dialysis patients. Though the literature is limited, kidneys from patients with ADPKD could be considered within extended criteria offers on a case-by-case basis.

Network pharmacology and experimental validation to investigate the mechanism of Nao-Ling-Su capsule in the treatment of ischemia/reperfusion-induced acute kidney injury

ETHNOPHARMACOLOGICAL RELEVANCE

Nao-Ling-Su Capsule (NLSC) is a traditional prescription, which is composed of fifteen herbs such as epimedium, Polygala tenuifolia, and Schisandra chinensis. It has the effect of strengthening the brain, calming nerves, and protecting the kidney, which has been used clinically for many years to strengthen the brain and kidney. However, the effect of NLSC in the treatment of acute kidney injury (AKI) is still unclear.

AIM OF THE STUDY

The present study aims to elucidate the pharmacological actions of NLSC in the treatment of AKI.

MATERIALS AND METHODS

Molecular targets for NLSC and AKI were obtained from various databases, and then we built networks of interactions between proteins (PPI) by employing string databases. Additionally, we employed the DAVID database to conduct gene ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Molecular docking was conducted to analyze the interaction between core components and their corresponding core targets. Next, the C57BL male mice model of ischemia/reperfusion damage (IRI) was developed, and the nephridial protective effect of NLSC was evaluated. The accuracy of the expected targets was confirmed using real-time quantitative polymerase chain reaction (RT-qPCR). The renal protective effect of NLSC was assessed using an immortalized human kidney tubular (HK-2) cell culture produced by oxygen-glucose deprivation (OGD).

RESULTS

Network pharmacology analysis identified 199 common targets from NLSC and AKI. STAT3, HSP90AA1, TP53, MAPK3, JUN, JAK2, and VEGFA could serve as potential drug targets and were associated with JAK2/STAT3 signaling pathway, PI3K-Akt signaling pathway, etc. The molecular docking analysis confirmed significant docking activity between the main bioactive components and core targets, including STAT3 and KIM-1. Moreover, the AKI mice model was successfully established and NLSC pretreatment could improve renal function and alleviate renal damage. NLSC could alleviate renal inflammation and tubular cell apoptosis, and decrease the expression of STAT3 and KIM-1 in AKI mice. In vitro, both NLSC and drug-containing serum may protect HK-2 cells by inhibiting STAT3 signaling, especially STAT3-mediated apoptosis and KIM-1 expression.

CONCLUSION

NLSC could alleviate renal inflammation and apoptosis, exerting its beneficial effects by targeting the STAT3/KIM-1 pathway. NLSC is a promising candidate for AKI treatment and provides a new idea and method for the treatment of AKI.

Phytochemical profiling and nephroprotective potential of ethanolic leaf extract of Polyalthia longifolia against cisplatin-induced oxidative stress in rat model

ETHNOPHARMACOLOGICAL RELEVANCE

Kidney problems are becoming more common globally and are considered a major health issue in the modern world with high mortality rate. Polyalthia longifolia (Sonn.) Thwaites is a tropical ethnomedicinal plant used to treat various diseases like diabetes, hypertension and urinary disorders and possess antioxidant and anti-inflammatory properties.

AIM OF THE STUDY

This study aimed to investigate the phytochemical composition of 70% ethanolic leaf extract of Polyalthia longifolia (Sonn.) Thwaites (PL) and evaluates its nephroprotective effects against cisplatin-induced nephrotoxicity in Wistar rats.

MATERIALS AND METHODS

The leaves of PL were extracted with 70% ethanol and performed the phytochemical profiling using Liquid Chromatography-Mass Spectrometry (LC-MS). The nephroprotective effect of PL leaf extract was evaluated at three doses (150, 300 and 600 mg/kg, p.o.) for 14 days against cisplatin toxicity (16 mg/kg, i.p., once) in male Wistar rats. Body and kidney weight indices, kidney function markers and lipid profile markers in serum, and oxidative stress markers in kidney tissue were performed along with the histopathological analysis of kidney.

RESULTS

The LC-MS chromatograph confirmed the presence of various phytocompounds include N-Methylhernagine (aporphine alkaloid), 4-Acetamidobutanoic acid (gamma amino acid) and choline, etc. in the PL leaf extract. Exposure of cisplatin (16 mg/kg, i.p., once only) to the animals significantly elevated the levels of kidney functional markers (i.e. serum urea, uric acid, creatinine) and the lipid markers (triglyceride and total cholesterol) in blood circulation with depletion of serum albumin which were reversed by the therapy of PL leaf extract (150, 300 and 600 mg/kg) in dose-dependent manner. The altered level of body and kidney weight in cisplatin treated group was also restored by the therapy. PL leaf extract effectively improved the antioxidant defense system of kidney at all doses by restoring the levels of tissue glutathione, superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase with the dose-dependent reduction of lipid peroxidation against cisplatin-induced renal oxidative stress. The histopathological observations also showed the significant recovery in cellular morphology after PL treatment when compared to the cisplatin toxicity group. The highest dose 600 mg/kg of PL leaf extract showed more pronounced renal recovery (p < 0.001) followed by other two doses, which was similar to the silymarin treatment group (a reference drug) against nephrotoxicity.

CONCLUSION

The results of this study revealed the nephroprotective effects of PL leaves against cisplatin-induced nephrotoxicity by reversing the level of biochemical markers and mitigating oxidative stress as well as improving the architecture of renal tissues. This renal protection by PL might be due to the synergistic effect of its phytoconstituents and antioxidant efficacy.

Reactive oxygen/nitrogen species scavenging and inflammatory regulation by renal-targeted bio-inspired rhodium nanozymes for acute kidney injury theranostics

Acute kidney injury (AKI) results from the rapid deterioration of renal function, which is mainly treated by transplantation and dialysis, and has a high mortality rate. Inflammation induced by excess reactive oxygen/nitrogen species (RONS) plays a crucial role in AKI. Although small molecule antioxidants have been utilized to alleviate AKI, low bioavailability and side-effect of these drugs tremendously limit their clinical use. Hence, we successfully construct ultra-small (2-4 nm) rhodium nanoparticles modified with l-serine (denoted as Rh-Ser). Our results show that Rh-Ser with multiple enzyme-mimicking activities, allows remove various RONS to protect damaged kidney cells. Additionally, the ultrasmall size of Rh-Ser is conducive to enrichment in the renal tubules, and the modification of l-serine enables Rh-Ser to bind to kidney injury molecule-1, which is highly expressed on the surface of damaged renal cells, thereby targeting the damaged kidney and increasing the retention time. Moreover, Rh-Ser allows the production of oxygen at the inflammatory site, thus further improving hypoxia and inhibiting pro-inflammatory macrophages to relieve inflammation, and increasing the survival rate of AKI mice from 0 to 80%, which exhibits a better therapeutic effect than that of small molecule drug. Photoacoustic and fluorescence imaging can effectively monitor and evaluate the enrichment and therapeutic effect of Rh-Ser. Our study provides a promising strategy for the targeted treatment of AKI via RONS scavenging and inflammatory regulation.

Long-term changes in cardiac remodelling in prevalent kidney graft recipients

BACKGROUND

Approximately 15% of kidney transplant (KT) recipients develop de novo heart failure after KT. There are scarce data reporting the long-term changes in cardiac structure and function among KT recipients. Despite the improvement in renal function, transplant-related complications as well as immunosuppressive therapy could have an impact on cardiac remodelling during follow-up. We aimed to describe the long-term changes in echocardiographic parameters in prevalent KT recipients and identify the clinical and laboratory factors associated with these changes.

METHODS

A centralised blinded review of two echocardiographic examinations after KT (on average after 17 and 39 months post-KT respectively) was performed among 80 patients (age 50.4 ± 16.2, diabetes 13.8% pre-KT), followed by linear regression to identify clinico-biological factors related to echocardiographic changes.

RESULTS

Left atrial volume index (LAVI) increased significantly (34.2 ± 10.8 mL/m2vs. 37.6 ± 15.0 mL/m2, annualised delta 3.1 ± 11.4 mL/m2/year; p = 0.034) while left ventricular ejection fraction (LVEF) decreased (62.1 ± 9.0% vs. 59.7 ± 9.9%, annualised delta -2.7 ± 13.6%/year; p = 0.04). Male sex (β = 8.112 ± 2.747; p < 0.01), pre-KT hypertension (β = 9.725 ± 4.156; p < 0.05), graft from expanded criteria donor (β = 3.791 ± 3.587; p < 0.05), and induction by anti-thymocyte globulin (β = 7.920 ± 2.974; p = 0.01) were associated with an increase in LAVI during follow-up. Higher haemoglobin (>12.9 g/dL) at the time of the first echocardiography (β = 6.029 ± 2.967; p < 0.05) and ACEi/ARB therapy (β = 8.306 ± 3.161; p < 0.05) were associated with an increase in LVEF during follow-up.

CONCLUSION

This study confirms the existence of long-term cardiac remodelling after KT despite dialysis cessation, characterised by an increase in LAVI and a decrease in LVEF. A better management of anaemia and using ACEi/ARB therapy may prevent such remodelling.

Safety of herbal decoctions: A scoping review of clinical studies in South Korea focusing on liver and kidney functions

ETHNOPHARMACOLOGICAL RELEVANCE

Approximately 27% of individuals seeking Korean medicine (KM) services in South Korea are prescribed herbal decoctions. The South Korean government has considered the validity of providing National Health Insurance coverage for herbal decoctions. Therefore, it is important to investigate their safety.

AIM OF THE STUDY

To investigate the safety of herbal decoctions commonly prescribed by KM doctors and to assess their effects on liver and kidney function by comprehensively analyzing Korean clinical studies in a scoping review.

MATERIALS AND METHODS

The Arksey and O'Malley framework and modified methods were applied in this scoping review. A comprehensive search of seven electronic health databases was conducted, and relevant clinical studies published between 2000 and 2022 were identified. Subsequently, only clinical studies reporting the results of liver and/or renal function tests in patient prescribed herbal decoctions by KM doctors were included. The characteristics of the included clinical studies and the reported proportion of each liver and/or renal function indicator were analyzed. Meta-analyses of the effects of herbal decoction on liver and/or renal function reported in prospective cohort studies were also performed.

RESULTS

Fifty-nine clinical studies were included in this review. The proportion of prospective cohort studies markedly decreased in the 2010s compared to the 2000s, while there was no noticeable change in the number of relevant clinical studies. Herbal decoctions were prescribed for less than one month in most included studies. Abnormal changes in liver or renal function indicators were identified in a small number of studies (3.70% and 7.69%, respectively). In a meta-analysis of 15 prospective cohort studies, no statistically significant changes in four liver function indices and two renal function indices were observed before and after the prescription of herbal decoctions.

CONCLUSIONS

Qualitative and quantitative analyses demonstrated favorable safety profiles for herbal decoctions. This scoping review includes the gaps noted between clinical application and research regarding the safety profiles of herbal decoctions. These findings could be used as evidence to support the inclusion of herbal decoction prescriptions in the National Health Insurance coverage in South Korea.

Inhibition of both NOX and TNF-α exerts substantial renoprotective effects in renal ischemia reperfusion injury rat model

BACKGROUND AND AIMS

Acute kidney injury (AKI) due to renal ischemia-reperfusion injury (RIRI) is associated with high morbidity and mortality, with no renoprotective drug available. Previous research focused on single drug targets, yet this approach has not reached translational success. Given the complexity of this condition, we aimed to identify a disease module and apply a multitarget network pharmacology approach.

METHODS

Identification of a disease module with potential drug targets was performed utilizing Disease Module Detection algorithm using NADPH oxidases (NOXs) as seeds. We then assessed the protective effect of a multitarget network pharmacology targeting the identified module in a rat model of RIRI. Rats were divided into five groups; sham, RIRI, and RIRI treated with setanaxib (NOX inhibitor, 10 mg/kg), etanercept (TNF-α inhibitor, 10 mg/kg), and setanaxib and etanercept (5 mg/kg each). Kidney functions, histopathological changes and oxidative stress markers (MDA and reduced GSH) were assessed. Immunohistochemistry of inflammatory (TNF-α, NF-κB) apoptotic (cCasp-3, Bax/Bcl 2), fibrotic (α-SMA) and proteolysis (MMP-9) markers was performed.

RESULTS

Our in-silico analysis yielded a disease module with TNF receptor 1 (TNFR1A) as the closest target to both NOX1 and NOX2. Targeting this module by a low-dose combination of setanaxib, and etanercept, resulted in a synergistic effect and ameliorated ischemic AKI in rats. This was evidenced by improved kidney function and reduced expression of inflammatory, apoptotic, proteolytic and fibrotic markers.

CONCLUSIONS

Our findings show that applying a multitarget network pharmacology approach allows synergistic renoprotective effect in ischemic AKI and might pave the way towards translational success.

Impact of renal denervation on patients with coronary microvascular dysfunction: study rationale and design

AIMS

Long-standing hypertension may cause an impairment in microvascular coronary circulation, which is involved in many different cardiac conditions. Renal sympathetic denervation (RDN) has been successfully proven as a valuable therapeutic choice for patients with resistant hypertension; moreover, the procedure looks promising in other settings, such as heart failure and atrial fibrillation, given its ability to downregulate the sympathetic nervous system, which is a recognized driver in these conditions as well as in microvascular dysfunction progression. The aim of this study is to explore the effect of RDN on coronary physiology in patients with ascertained coronary microvascular dysfunction and resistant hypertension.

METHODS

This is a multicenter, prospective, nonrandomized, open-label, interventional study. Consecutive patients with resistant hypertension, nonobstructive coronary artery disease (NOCAD) and documented microvascular dysfunction will be enrolled. Patients will undergo RDN by Spyral Symplicity 3 (Medtronic Inc, Minneapolis, Minnesota, USA) and reassessment of coronary microvascular function 6 months after the procedure. Primary endpoint will be the difference in the index of microcirculatory resistance.

CONCLUSION

The IMPRESSION study seeks to evaluate if there is any pleiotropic effect of the RDN procedure that results in modulation of microvascular function; if observed, this would be the first evidence showing RDN as a valuable therapy to revert hypertension-related microvascular dysfunction.

Environmental fluoride exposure and implications on potential pediatric kidney health risks: an approach with urinary biomarkers

BACKGROUND

Environmental fluoride exposure at elevated levels is potentially linked to kidney injury, and may contribute to chronic kidney disease of uncertain etiology (CKDu) as a risk factor. However, this link remains unclear, and examining the risk of kidney damage from early life fluoride exposure may provide important insights. Hence, this study aimed to investigate associations of fluoride exposure with pediatric kidney health in CKDu impacted and unimpacted communities in Sri Lanka.

METHODS

Considering the geographical variations in environmental fluoride, climate, and prevalence of CKDu, four study groups were established within selected education zones in CKDu-endemic dry zone regions (D-En), and CKDu-nonendemic regions within the dry (D-NE), wet (W-NE), and intermediate (I-NE) climatic zones. The study population included 922 school students (11-18 years of age). Participants in each group were divided into four subgroups based on quartiles of respective urinary fluoride (UF) distribution for comparison of urinary kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), and albumin-creatinine ratio (ACR).

RESULTS

UF levels in participants particularly in CKDu endemic dry zone regions were significantly high compared to the other regions. Significantly high median urinary NGAL (in D-NE) and ACR (in D-EN, and W-NE) levels were observed in subgroups of higher UF quartiles. Albuminuria was not particularly identified in subjects with high UF excretion. Urinary KIM-1 showed no significant variation across the UF quartile subgroups. Linear regression identified weak associations of UF with kidney injury biomarkers.

CONCLUSIONS

Fluoride exposure is particularly high in CKDu-endemic dry zone communities. As implied by kidney injury biomarkers, a strong link between fluoride exposure and pediatric kidney health was not evident at the observed exposure levels in the study regions.

Cystatin C should be routinely available for estimating kidney function

PURPOSE OF REVIEW

In this report, we summarize why the availability of cystatin C is important across a variety of clinical scenarios, the recent literature on when, why and in whom cystatin C testing should be considered, and how nephrologists can take practical steps to incorporate cystatin C testing into their practice.

RECENT FINDINGS

Large intra-individual discrepancies between estimated glomerular filtration rate by creatinine (eGFRcr) and estimated glomerular filtration rate by creatinine eGFRcys (known as eGFRdiff) are observed in at least 1 in 4 people. These differences are seen more commonly among more vulnerable individuals: older adults, females, non-White individuals and those living with multiple medical conditions. A large eGFRdiff, where eGFRcys is lower than eGFRcr, is associated with a plethora of adverse outcomes, including medication-associated adverse events, acute kidney injury, cardiovascular disease, kidney failure and all-cause mortality. Among studies that have measured GFR, eGFRcr-cys usually provides the most accurate estimation of kidney function compared to mGFR, including among participants with large discrepancies between eGFRcr and eGFRcys.

SUMMARY

Cystatin C improves sensitivity and specificity of chronic kidney disease diagnosis, improves detection of harmful acute and chronic changes in kidney function, improves precision of treatment eligibility and safety, and may reduce healthcare inequalities. Better education, curiosity, and motivation among nephrologists could substantially improve the availability and utilization of cystatin C.

Unintentional Injury Death Among Solid Organ Transplant Recipients: Trends and Risk Factors

Unintentional injury death (UID) is a leading cause of mortality worldwide, and individuals with chronic diseases are at higher risk. Though organ transplant can improve the lives of those with chronic disease, these individuals remain in suboptimal physical and mental health after surgery that predisposes them to UID. To quantify the scale of UID among solid organ transplant recipients, we performed a retrospective analysis using United Network of Organ Sharing data from adults who underwent kidney, liver or pancreas transplant between 2000-2021. Our study aimed to identify risk factors for UID in this cohort by comparing basic patient, donor, and transplant characteristics of the groups (UID or all other cause death). The largest proportion of UID was seen in the kidney group (.8%), followed by liver (.7%) and then pancreas (.3%). Male sex was the most significant risk factor among kidney and liver recipients. Whites had a higher risk for UID relative to their non-White counterparts in the kidney and liver groups. In both groups, advancing age conferred a protective effect, whereas higher functional status was a risk factor. Our findings shed new light on a significant source of mortality within the transplant population.

Estimating risk of rapid disease progression in pediatric patients with autosomal dominant polycystic kidney disease: a randomized trial of tolvaptan

BACKGROUND

Tolvaptan preserves kidney function in adults with autosomal dominant polycystic kidney disease (ADPKD) at elevated risk of rapid progression. A trial (NCT02964273) evaluated tolvaptan safety and pharmacodynamics in children (5-17 years). However, progression risk was not part of study eligibility criteria due to lack of validated criteria for risk assessment in children. As risk estimation is important to guide clinical management, baseline characteristics of the study participants were retrospectively evaluated to determine whether risk of rapid disease progression in pediatric ADPKD can be assessed and to identify parameters relevant for risk estimation.

METHODS

Four academic pediatric nephrologists reviewed baseline data and rated participant risk from 1 (lowest) to 5 (highest) based on clinical judgement and the literature. Three primary reviewers independently scored all cases, with each case reviewed by two primary reviewers. For cases with discordant ratings (≥ 2-point difference), the fourth reviewer provided a secondary rating blinded to the primary evaluations. Study participants with discordant ratings and/or for whom data were lacking were later discussed to clarify parameters relevant to risk estimation.

RESULTS

Of 90 evaluable subjects, primary reviews of 69 (77%) were concordant. The proportion considered at risk of rapid progression (final mean rating ≥ 3.5) by age group was: 15-17 years, 27/34 (79%); 12- < 15, 9/32 (28%); 4- < 12, 8/24 (33%). The panelists agreed on characteristics important for risk determination: age, kidney imaging, kidney function, blood pressure, urine protein, and genetics.

CONCLUSIONS

High ratings concordance and agreement among reviewers on relevant clinical characteristics support the feasibility of pediatric risk assessment.

Novel indications for referral and care for simultaneous liver kidney transplant recipients

PURPOSE OF REVIEW

Kidney dysfunction is challenging in liver transplant candidates to determine whether it is reversible or not. This review focuses on the pertinent data on how to best approach liver transplant candidates with kidney dysfunction in the current era after implementing the simultaneous liver kidney (SLK) allocation policy and safety net.

RECENT FINDINGS

The implementation of the SLK policy inverted the steady rise in SLK transplants and improved the utilization of high-quality kidneys. Access to kidney transplantation following liver transplant alone (LTA) increased with favorable outcomes. Estimating GFR in liver transplant candidates remains challenging, and innovative methods are needed. SLK provided superior patient and graft survival compared to LTA only for patients with advanced CKD and dialysis at least 3 months. SLK can provide immunological protection against kidney rejection in highly sensitized candidates. Post-SLK transplant care is complex, with an increased risk of complications and hospitalization.

SUMMARY

The SLK policy improved kidney access and utilization. Transplant centers are encouraged, under the safety net, to reserve SLK for liver transplant candidates with advanced CKD or dialysis at least 3 months while allowing lower thresholds for highly sensitized patients. Herein, we propose a practical approach to liver transplant candidates with kidney dysfunction.

Deep hybrid modeling of a HEK293 process: Combining long short-term memory networks with first principles equations

The combination of physical equations with deep learning is becoming a promising methodology for bioprocess digitalization. In this paper, we investigate for the first time the combination of long short-term memory (LSTM) networks with first principles equations in a hybrid workflow to describe human embryonic kidney 293 (HEK293) culture dynamics. Experimental data of 27 extracellular state variables in 20 fed-batch HEK293 cultures were collected in a parallel high throughput 250 mL cultivation system in an industrial process development setting. The adaptive moment estimation method with stochastic regularization and cross-validation were employed for deep learning. A total of 784 hybrid models with varying deep neural network architectures, depths, layers sizes and node activation functions were compared. In most scenarios, hybrid LSTM models outperformed classical hybrid Feedforward Neural Network (FFNN) models in terms of training and testing error. Hybrid LSTM models revealed to be less sensitive to data resampling than FFNN hybrid models. As disadvantages, Hybrid LSTM models are in general more complex (higher number of parameters) and have a higher computation cost than FFNN hybrid models. The hybrid model with the highest prediction accuracy consisted in a LSTM network with seven internal states connected in series with dynamic material balance equations. This hybrid model correctly predicted the dynamics of the 27 state variables (R2 = 0.93 in the test data set), including biomass, key substrates, amino acids and metabolic by-products for around 10 cultivation days.

Has the time come for age-adapted glomerular filtration rate criteria to define chronic kidney disease: how soon is now?

PURPOSE OF REVIEW

The conventional definition of chronic kidney disease (CKD) primarily relies on the identification of albuminuria or a decline in estimated glomerular filtration rate (eGFR). For many years, a straightforward eGFR threshold of <60 ml/min/1.73 m 2 has been widely adopted as the standard for defining CKD. Nonetheless, this criterion fails to consider the natural aging process of the kidney, and this oversight may affect the accurate diagnosis of kidney disease particularly at the extremes of age.

RECENT FINDINGS

The fixed eGFR threshold of <60 ml/min/1.73 m 2 for defining CKD misses crucial opportunities for risk prevention. Studies have revealed that the eGFR threshold at which the risks for adverse long-term health outcomes such as mortality, cardiovascular events, and kidney failure begin to rise varies substantially by age. Specifically, this threshold is lower for the elderly and higher for young adults. Consequently, this results in the over-diagnosis of kidney disease in the elderly and the under-diagnosis of kidney disease in young adults.

SUMMARY

To address these limitations of the current CKD definition, we discuss a number of proposed age-adapted eGFR criteria and weigh their pros and cons against the current, simple, and universally accepted approach.

Role of the complement system in kidney cell death induced by Loxosceles venom Sphingomyelinases D

Envenomation by Loxosceles spiders can result in local and systemic pathologies. Systemic loxoscelism, which can lead to death, is characterized by intravascular hemolysis, platelet aggregation, and acute kidney injury. Sphingomyelinase D (SMase D) in Loxosceles spider venom is responsible for both local and systemic pathologies, and has been shown to induce metalloprotease activity. As the complement system is involved in many renal pathologies and is involved in hemolysis in systemic loxoscelism, the aim of this study was to investigate its role and the role of complement regulators and metalloproteases in an in vitro model of Loxosceles venom induced renal pathology. We investigated the effects of the venom/SMase D and the complement system on the HK-2 kidney cell line. Using cell viability assays, western blotting, and flow cytometry, we show that human serum, as a source of complement, enhanced the venom/SMase D induced cell death and the deposition of complement components and properdin. Inhibitors for ADAM-10 and ADAM-17 prevented the venom induced release of the of the complement regulator MCP/CD46 and reduced the venom/SMase D induced cell death. Our results show that the complement system can contribute to Loxosceles venom induced renal pathology. We therefore suggest that patients experiencing systemic loxoscelism may benefit from treatment with metalloproteinase inhibitors and complement inhibitors, but this proposition should be further analyzed in future pre-clinical and clinical assays.

Artificial intelligence and machine learning trends in kidney care

BACKGROUND

The integration of artificial intelligence (AI) and machine learning (ML) in kidney care has seen a significant rise in recent years. This study specifically analyzed AI and ML research publications related to kidney care to identify leading authors, institutions, and countries in this area. It aimed to examine publication trends and patterns, and to explore the impact of collaborative efforts on citation metrics.

METHODS

The study used the Science Citation Index Expanded (SCI-EXPANDED) of Clarivate Analytics Web of Science Core Collection to search for AI and machine learning publications related to nephrology from 1992 to 2021. The authors used quotation marks and Boolean operator "or" to search for keywords in the title, abstract, author keywords, and Keywords Plus. In addition, the 'front page' filter was applied. A total of 5425 documents were identified and analyzed.

RESULTS

The results showed that articles represent 75% of the analyzed documents, with an average author to publications ratio of 7.4 and an average number of citations per publication in 2021 of 18. English articles had a higher citation rate than non-English articles. The USA dominated in all publication indicators, followed by China. Notably, the research also showed that collaborative efforts tend to result in higher citation rates. A significant portion of the publications were found in urology journals, emphasizing the broader scope of kidney care beyond traditional nephrology.

CONCLUSIONS

The findings underscore the importance of AI and ML in enhancing kidney care, offering a roadmap for future research and implementation in this expanding field.

Selective Partitioned Regression for Accurate Kidney Health Monitoring

The number of people diagnosed with advanced stages of kidney disease have been rising every year. Early detection and constant monitoring are the only minimally invasive means to prevent severe kidney damage or kidney failure. We propose a cost-effective machine learning-based testing system that can facilitate inexpensive yet accurate kidney health checks. Our proposed framework, which was developed into an iPhone application, uses a camera-based bio-sensor and state-of-the-art classical machine learning and deep learning techniques for predicting the concentration of creatinine in the sample, based on colorimetric change in the test strip. The predicted creatinine concentration is then used to classify the severity of the kidney disease as healthy, intermediate, or critical. In this article, we focus on the effectiveness of machine learning models to translate the colorimetric reaction to kidney health prediction. In this setting, we thoroughly evaluated the effectiveness of our novel proposed models against state-of-the-art classical machine learning and deep learning approaches. Additionally, we executed a number of ablation studies to measure the performance of our model when trained using different meta-parameter choices. Our evaluation results indicate that our selective partitioned regression (SPR) model, using histogram of colors-based features and a histogram gradient boosted trees underlying estimator, exhibits much better overall prediction performance compared to state-of-the-art methods. Our initial study indicates that SPR can be an effective tool for detecting the severity of kidney disease using inexpensive lateral flow assay test strips and a smart phone-based application. Additional work is needed to verify the performance of the model in various settings.

Cost-effectiveness of sodium zirconium cyclosilicate for advanced chronic kidney patients in Singapore

INTRODUCTION

Hyperkalaemia (HK) is prevalent among patients with chronic kidney disease (CKD) and chronic heart failure, especially if they are treated with renin-angiotensin-aldosterone system inhibitors (RAASi). This study evaluated the cost-effectiveness of a newly developed anti-HK therapy, sodium zirconium cyclosilicate (SZC), to the current standard of care for treating HK in advanced CKD patients from the Singapore health system perspective.

METHODS

We adapted a global microsimulation model to simulate individual patients' potassium level trajectories with baseline potassium ≥5.5 mmol/L, CKD progression, changes in treatment, and other fatal and non-fatal events. Effectiveness data was derived from ZS-004 and ZS-005 trials. Model parameters were localised using CKD patients' administrative and medical records at the Singapore General Hospital Department of Renal Medicine. We estimated the lifetime cost and quality-adjusted life years (QALYs) of each HK treatment, and the incremental cost-effectiveness ratio of SZC.

RESULTS

SZC demonstrated cost-effectiveness with an incremental cost-effectiveness ratsio of SGD 45 068 per QALY over a lifetime horizon, below the willingness-to-pay threshold of SGD 90 000 per QALY. Notably, SZC proved most cost-effective for patients with less severe CKD who were concurrently using RAASi. Sensitivity analyses confirmed the robustness of the findings, accounting for alternative parameter values and statistical uncertainty.

CONCLUSION

This study establishes the cost-effectiveness of SZC as a treatment for HK, highlighting its potential to mitigate the risk of hyperkalaemia and optimise RAASi therapy. These findings emphasise the value of integrating SZC into the Singapore health system for improved patient outcomes and resource allocation.

Eucalyptol regulates Nrf2 and NF-kB signaling and alleviates gentamicin-induced kidney injury in rats by downregulating oxidative stress, oxidative DNA damage, inflammation, and apoptosis

Gentamicin, an aminoglycoside antibiotic, is nowadays widely used in the treatment of gram-negative microorganisms. The antimicrobial, anti-inflammatory, and antioxidant activities of eucalyptol, a type of saturated monoterpene, have been reported in many studies. The aim of this study was to examine the possible effects of eucalyptol on gentamicin-induced renal toxicity. A total of 32 rats were divided into 4 groups; Control (C), Eucalyptol (EUC), Gentamicin (GEN), and Gentamicin + Eucalyptol (GEN + EUC). In order to induce renal toxicity, 100 mg/kg gentamicin was administered intraperitoneally (i.p.) for 10 consecutive days in the GEN and GEN + EUC groups. EUC and GEN + EUC groups were given 100 mg/kg orally of eucalyptol for 10 consecutive days. Afterwards, rats were euthanized and samples were taken and subjected to histopathological, biochemical, immunohistochemical, and real-time PCR examinations. The blood urea nitrogen (BUN) and creatinine (CRE) levels were significantly decreased in the GEN + EUC group (0.76 and 0.69-fold, respectively) compared to the GEN group. The glutathione peroxidase (GPx) and catalase (CAT) activities were significantly increased in the GEN + EUC group (1.35 and 2.67-fold, respectively) compared to the GEN group. In GEN group, Nuclear factor kappa B (NF-kB), Interleukin 1-beta (IL-1β), Inducible nitric oxide synthase (iNOS), Tumor necrosis factor-α (TNF-α), Caspase-3, 8-Hydroxy-2'-deoxyguanosine (8-OHdG) and Nuclear factor erythroid 2-related factor (Nrf2) expression levels were found to be quite irregular. GEN + EUC group decreased the expressions of NF-kB, IL-1β, iNOS, TNF-α, Caspase-3, and 8-OHdG (0.55, 0.67, 0.54, 0.54, 0.63 and 0.67-fold, respectively), while it caused increased expression of Nrf2 (3.1 fold). In addition, eucalyptol treatment ameliorated the histopathological changes that occurred with gentamicin. The results of our study show that eucalyptol has anti-inflammatory, antioxidative, antiapoptotic, nephroprotective, and curative effects on gentamicin-induced nephrotoxicity.