Variational autoencoders for generative modeling of drug dosing determinants in renal, hepatic, metabolic, and cardiac disease states.

Physiological determinants of drug dosing (PDODD) are a promising approach for precision dosing. This study investigates the alterations of PDODD in diseases and evaluates a variational autoencoder (VAE) artificial intelligence model for PDODD. The PDODD panel contained 20 biomarkers, and 13 renal, hepatic, diabetes, and cardiac disease status variables. Demographic characteristics, anthropometric measurements (body weight, body surface area, waist circumference), blood (plasma volume, albumin), renal (creatinine, glomerular filtration rate, urine flow, and urine albumin to creatinine ratio), and hepatic (R-value, hepatic steatosis index, drug-induced liver injury index), blood cell (systemic inflammation index, red cell, lymphocyte, neutrophils, and platelet counts) biomarkers, and medical questionnaire responses from the National Health and Nutrition Examination Survey (NHANES) were included. The tabular VAE (TVAE) generative model was implemented with the Synthetic Data Vault Python library. The joint distributions of the generated data vs. test data were compared using graphical univariate, bivariate, and multidimensional projection methods and distribution proximity measures. The PDODD biomarkers related to disease progression were altered as expected in renal, hepatic, diabetes, and cardiac diseases. The continuous PDODD panel variables generated by the TVAE satisfactorily approximated the distribution in the test data. The TVAE-generated distributions of some discrete variables deviated from the test data distribution. The age distribution of TVAE-generated continuous variables was similar to the test data. The TVAE algorithm demonstrated potential as an AI model for continuous PDODD and could be useful for generating virtual populations for clinical trial simulations.

An antibody that inhibits TGF-ß1 release from latent extracellular matrix complexes attenuates the progression of renal fibrosis.

Inhibitors of the transforming growth factor-ß (TGF-ß) pathway are potentially promising antifibrotic therapies, but nonselective simultaneous inhibition of all three TGF-ß homologs has safety liabilities. TGF-ß1 is noncovalently bound to a latency-associated peptide that is, in turn, covalently bound to different presenting molecules within large latent complexes. The latent TGF-ß-binding proteins (LTBPs) present TGF-ß1 in the extracellular matrix, and TGF-ß1 is presented on immune cells by two transmembrane proteins, glycoprotein A repetitions predominant (GARP) and leucine-rich repeat protein 33 (LRRC33). Here, we describe LTBP-49247, an antibody that selectively bound to and inhibited the activation of TGF-ß1 presented by LTBPs but did not bind to TGF-ß1 presented by GARP or LRRC33. Structural studies demonstrated that LTBP-49247 recognized an epitope on LTBP-presented TGF-ß1 that is not accessible on GARP- or LRRC33-presented TGF-ß1, explaining the antibody's selectivity for LTBP-complexed TGF-ß1. In two rodent models of kidney fibrosis of different etiologies, LTBP-49247 attenuated fibrotic progression, indicating the central role of LTBP-presented TGF-ß1 in renal fibrosis. In mice, LTBP-49247 did not have the toxic effects associated with less selective TGF-ß inhibitors. These results establish the feasibility of selectively targeting LTBP-bound TGF-ß1 as an approach for treating fibrosis.

Renal impairment in monoclonal gammopathies and multiple myeloma.

The incidence of monoclonal gammopathy (MG) increases with age. In individuals over 80 years of age, we can diagnose the presence of monoclonal immunoglobulin (MIg) in up to 10 % of cases. Not only malignant diseases such as multiple myeloma (MM), but also benign forms such as MGUS (monoclonal gammopathy of undetermined significance) can lead to renal involvement. The light chains of immunoglobulins (LC) are the most damaging to the kidneys, as they are freely filtered into the urine due to their molecular weight. Detection of MIg relies mainly on a combination of immunofixation electrophoresis of serum (IELFO) and urine and determination of free light chains (FLC) of kappa and lambda and their ratio (κ/λ) in serum. The combination of these tests will detect the presence of MIg with 99 % sensitivity. Renal damage in MG may be caused by direct deposition of MIg in the glomeruli (e.g. AL amyloidosis, LC deposition disease) or tubules (in the distal tubule as a myeloma kidney or in the proximal tubule as Fanconi syndrome or proximal tubulopathy). Typical urinary findings in these diseases are moderate or severe proteinuria or nephrotic syndrome. Acute kidney injury (AKI) can be expected especially when serum FLC is >500 mg/l. Renal biopsy is crucial to establish an accurate diagnosis and thus initiate the correct treatment. Treatment of these types of renal damage involves the same treatment regimens used in the treatment of MM, including proteasome inhibitors or daratumumab.

[Obesity and kidney disease]. / Adipositas und Nierenerkrankungen.

INTRODUCTION: The obesity epidemic has led to an increased prevalence of obesity-related glomerulopathy (ORG). This disease is characte-rized by proteinuria, glomerulomegaly, progressive glomerulosclerosis and a decline in renal function. Individuals with obesity frequently display arterial hypertension and diabetes mellitus, exacerbating renal damage. The pathogenesis involves overactivation of the RAAS (Renin-Angiotensin-Aldosterone System), glomerular hyperfiltration, an inflammatory state with oxidative stress, hyperinsulinemia-induced hemodynamic alterations and lipotoxicity. Additionally, obesity represents a significant risk factor for kidney stone formation, further contributing to renal damage. The management of obesity-induced nephropathy primarily involves weight reduction strategies and optimized control of blood pressure and metabolic factors. Early detection is crucial to counteract the progression of kidney disease. Noteworthy, obesity significantly complicates the implementation of renal replacement procedures, including kidney transplantation, and increases the rate of complications. In summary, there are many reasons why obesity should gain attention in the field of nephrology.

Longitudinal Analysis of Renal Function Changes in Elderly Populations: Health Status Evaluation and Risk Factor Assessment.

Background: This study aims to investigate GFR decline in elderly subjects with varying physical conditions and analyze key risk factors impacting renal function changes. Methods: We obtained data from patients between 2017 and 2019, and matched healthy elderly subjects based on gender and age. Data collected for all subjects included annual measurements of fast blood glucose (GLU), glycated hemoglobin (HbA1c), low-density lipoprotein cholesterol (LDL-c), blood albumin (ALB), blood uric acid (UA), urine protein (UP), and systolic blood pressure (SBP). Additionally, information on coexisting diseases was gathered. The Full Age Spectrum (FAS) equation was used to calculate eGFR. Results: A total of 162 patients with complete 3-year renal dynamic imaging were included, including 84 patients in the kidney disease group (K group) and 78 patients in the non-kidney disease group (NK group). Ninety individuals were selected as the healthy group (H group). The annual decline rate in the K group was the fastest, which exceeded 5mL/min/1.73m2 (P < 0.05). Group (K group: ß=-40.31, P<0.001; NK group: ß=-26.96, P<0.001), ALB (ß=-0.38, P=0.038) and HbA1c (ß=1.36, P=0.029) had a significant negative impact on the eGFR changes. For participants who had negative proteinuria: K group had the most significant annual eGFR decline. Conclusion: The presence of kidney disease, along with proteinuria nor not, can lead to a marked acceleration in kidney function decline in elderly. We categorize elderly individuals with an annual eGFR decline of more than 5 mL/min/1.73m2 as the "kidney accelerated aging" population.

Salt-losing nephropathy associated with supraventricular arrhythmia.

We present a case of a young man with a new-onset supraventricular arrhythmia accompanied by polyuria and natriuresis with subsequent renal salt-wasting causing hypovolemic hyponatremia. Resolution of the electrolyte imbalance occurred only after successful atrial flutter ablation.

The ANGPTL4-HIF-1α loop: a critical regulator of renal interstitial fibrosis.

BACKGROUND: Renal interstitial fibrosis (RIF) is a progressive, irreversible terminal kidney disease with a poor prognosis and high mortality. Angiopoietin-like 4 (ANGPTL4) is known to be associated with fibrosis in various organs, but its impact on the RIF process remains unclear. This study aimed to elucidate the role and underlying mechanisms of ANGPTL4 in the progression of RIF. METHODS: In vivo, a chronic kidney disease (CKD) rat model of renal interstitial fibrosis was established via intragastric administration of adenine at different time points (4 and 6 weeks). Blood and urine samples were collected to assess renal function and 24-h urinary protein levels. Kidney tissues were subjected to HE and Masson staining for pathological observation. Immunohistochemistry and real-time quantitative PCR (qRT‒PCR) were performed to evaluate the expression of ANGPTL4 and hypoxia-inducible factor-1α (HIF-1α), followed by Pearson correlation analysis. Subsequently, kidney biopsy tissues from 11 CKD patients (6 with RIF and 5 without RIF) were subjected to immunohistochemical staining to validate the expression of ANGPTL4. In vitro, a fibrosis model of human renal tubular epithelial cells (HK2) was established through hypoxic stimulation. Subsequently, an HIF-1α inhibitor (2-MeOE2) was used, and ANGPTL4 was manipulated using siRNA or plasmid overexpression. Changes in ANGPTL4 and fibrosis markers were analyzed through Western blotting, qRT‒PCR, and immunofluorescence. RESULTS: ANGPTL4 was significantly upregulated in the CKD rat model and was significantly positively correlated with renal injury markers, the fibrotic area, and HIF-1α. These results were confirmed by clinical samples, which showed a significant increase in the expression level of ANGPTL4 in CKD patients with RIF, which was positively correlated with HIF-1α. Further in vitro studies indicated that the expression of ANGPTL4 is regulated by HIF-1α, which in turn is subject to negative feedback regulation by ANGPTL4. Moreover, modulation of ANGPTL4 expression influences the progression of fibrosis in HK2 cells. CONCLUSION: Our findings indicate that ANGPTL4 is a key regulatory factor in renal fibrosis, forming a loop with HIF-1α, potentially serving as a novel therapeutic target for RIF.

Potential effects of Resatorvid and alpha lipoic acid on gentamicin-induced nephrotoxicity in rats.

Gentamicin is an aminoglycoside antibiotic with a rapid bactericidal effect on the treatment of many infections. However, its use at high concentrations for more than 7 days causes nephrotoxic side effects. This study investigated the potential of Resatorvid and alpha lipoic acid (ALA) in mitigating gentamicin-induced nephrotoxicity in rats, considering biochemical, histopathological, and molecular parameters. This study randomly distributed 34 Wistar albino rats into four groups: healthy control (n = 6), Gentamicin (80 mg/kg, n = 7), Gentamicin + Sham (%10 hydroalcoholic solution, n = 7), Gentamicin + Resatorvid (5 mg/kg, n = 7), and Gentamicin + ALA (100 mg/kg, n = 7). Resatorvid treatment led to a statistically significant decrease in urinary IL-18, KIM-1, and NGAL levels, whereas ALA treatment significantly reduced KIM-1 levels compared to the gentamicin-only group. Both Resatorvid and ALA showed partial reductions in urine creatinine levels. Moreover, treatments with Resatorvid and ALA resulted in statistically significant decreases in NRF-2, CAS-3, and NR4A2 expressions. However, only Resatorvid demonstrated a statistically significant decrease in NF-B expression. These findings highlight the potential of Resatorvid in ameliorating gentamicin-induced nephrotoxicity, thereby expanding the therapeutic utility of gentamicin and enhancing its efficacy against infections.

Role of the Innate Immune Response in Glomerular Disease Pathogenesis: Focus on Podocytes.

Accumulating evidence indicates that inflammatory and immunologic processes play a significant role in the development and progression of glomerular diseases. Podocytes, the terminally differentiated epithelial cells, are crucial for maintaining the integrity of the glomerular filtration barrier. Once injured, podocytes cannot regenerate, leading to progressive proteinuric glomerular diseases. However, emerging evidence suggests that podocytes not only maintain the glomerular filtration barrier and are important targets of immune responses but also exhibit many features of immune-like cells, where they are involved in the modulation of the activity of innate and adaptive immunity. This dual role of podocytes may lead to the discovery and development of new therapeutic targets for treating glomerular diseases. This review aims to provide an overview of the innate immunity mechanisms involved in podocyte injury and the progression of proteinuric glomerular diseases.

Predictive value of inflammatory prognostic index for contrast-induced nephropathy in patients undergoing coronary angiography and/or percutaneous coronary intervention.

The purpose of this study was to investigate the relationship between Inflammatory Prognostic Index (IPI) levels and Contrast-Induced Nephropathy (CIN) risk and postoperative clinical outcomes in patients undergoing coronary angiography (CAG) and/or percutaneous coronary intervention (PCI). A total of 3,340 consecutive patients who underwent CAG and/or PCI between May 2017 and December 2022 were enrolled in this study. Based on their baseline IPI levels, patients were categorized into four groups. Clinical characteristics and postoperative outcomes were compared among these groups. In-hospital outcomes focused on CIN risk, repeated revascularization, major bleeding, and major adverse cardiovascular events (MACEs), while the long-term outcome examined the all-cause readmission rate. Quartile analysis found a significant link between IPI levels and CIN risk, notably in the highest quartile (P < 0.001). Even after adjusting for baseline factors, this association remained significant, with an adjusted Odds Ratio (aOR) of 2.33 (95%CI 1.50-3.64; P = 0.001). Notably, baseline IPI level emerged as an independent predictor of severe arrhythmia, with aOR of 0.50 (95%CI 0.35-0.69; P < 0.001), particularly driven by the highest quartile. Furthermore, a significant correlation between IPI and acute myocardial infarction was observed (P < 0.001), which remained significant post-adjustment. For patients undergoing CAG and/or PCI, baseline IPI levels can independently predict clinical prognosis. As a comprehensive inflammation indicator, IPI effectively identifies high-risk patients post-procedure. This study underscores IPI's potential to assist medical professionals in making more precise clinical decisions, ultimately reducing mortality and readmission rates linked to cardiovascular disease (CVD).

Angiotensin II-independent abnormal renal vascular reactivity during puromycin nephropathy.

Experimental glomerulonephritis results in hypertension that is sensitive to salt. Nevertheless, salt retention alone cannot explain the increase in blood pressure. Angiotensin antagonistic therapy reduces hypertension caused by puromycin amino nucleosides (PAN). We investigated the hypothesis that PAN modifies renal vascular reactivity through processes dependent on angiotensin. Long-Evans rats were given an intraperitoneal injection of either puromycin (150 mg/kg) or saline (controls). Group 1 was fed a normal sodium diet (NSD, n = 9). Group 2 was given 30 mg/L of quinapril (Q) in addition to NSD (NSD + Q; n = 6). Group 3 received a high sodium diet (HSD, n = 7), and Group 4 received HSD + Q (n = 7). Systolic blood pressure (SBP), plasma creatinine, proteinuria, and sodium balance were monitored for 12 days. On day 15, renal vascular reactivity was assessed by administering increasing doses of angiotensin II, acetylcholine (ACh), and sodium nitroprusside (SNP) directly into the renal artery. SBP progressively increased in all PAN groups. This increase in SBP was greater in the HSD groups and was not significantly altered by Q treatment. SBP increased by 22 ± 4% (NSD), 51 ± 5% (NSD + Q), 81 ± 10% (HSD), and 65 ± 8% (HSD + Q). The renal blood flow of PAN rats did not return to baseline despite their normal renal vasoconstrictor responses to angiotensin II. Additionally, they showed reduced renal vasodilator responses to SNP and Ach. The vasodilator responses to both vasodilators were surprisingly unaffected by the inhibition of the angiotensin-converting enzyme (ACE). Renal vasodilator responses to both endothelium-dependent and independent variables were reduced in early PAN-induced hypertension. We found that the angiotensin-mediated mechanism is not responsible for this altered renal vasoreactivity.

Urinary N-acetyl-D-glucosaminidase can predict bleeding after a percutaneous kidney biopsy.

BACKGROUND: A percutaneous kidney biopsy (PKB) allows nephrologists to make informed decisions for treating various kidney diseases; however, the risk of bleeding complications should be considered, given the vascularity of the kidney. Many studies have reported risk factors for bleeding events after a PKB. However, while urinary N-acetyl-ß-D-glucosaminidase (NAG) is a useful biomarker of kidney disease severity, little is known about whether or not urinary NAG is related to the bleeding risk. METHODS: Medical records of patients who underwent a PKB at the National Defense Medical College Hospital between October 2018 and October 2023 were retrospectively studied. Hemoglobin (Hb) loss ≥ 1 g/dL was defined as a bleeding event. RESULTS: Of the 213 patients, 110 (51.6%) were men, and the median age was 56 years old (interquartile range 40-71). The most frequent diagnosis on a PKB was IgA nephropathy (N = 72; 34.0%). Fifty-four patients (25.3%) experienced Hb loss ≥ 1 g/dL after a PKB, and urinary NAG/Cr levels before the biopsy were able to predict a bleeding event, with an area under the receiver operating characteristic curve of 0.65 (p = 0.005). Using the optimal cutoff value of 35 U/gCr, urinary NAG/Cr was found to be an independent risk factor by multiple logistic regression analysis (odds ratio 3.21, 95% confidence interval 1.42-7.27, p = 0.005). Even after adjusting for previously-reported risk factors, the elevated urinary NAG/Cr ratio remained a statistically significant variable. Compared with the pathological findings, only the severity of multilayered elastic laminae of the small muscular artery was associated with both urinary NAG/Cr levels (p = 0.008) and bleeding events (p = 0.03). CONCLUSION: Urinary NAG successfully predicted not only the severity of kidney disorders but also bleeding events after a PKB. Arteriosclerosis in the kidneys may be the mechanism underlying these increased bleeding events.

Combined UPLC-QqQ-MS/MS and AP-MALDI Mass Spectrometry Imaging Method for Phospholipidomics in Obese Mouse Kidneys: Alleviation by Feeding Sea Cucumber Phospholipids.

Sea cucumber phospholipids have ameliorative effects on various diseases related to lipid metabolism. However, it is unclear whether it can ameliorate obesity-associated glomerulopathy (ORG) induced by a high-fat diet (HFD). The present study applied UPLC-QqQ-MS/MS and atmospheric pressure matrix-assisted laser desorption ionization mass spectrometry imaging (AP-MALDI MSI) to investigate the effects of sea cucumber phospholipids, including plasmalogen PlsEtn and plasmanylcholine PakCho, on phospholipid profiles in the HFD-induced ORG mouse kidney. Quantitative analysis of 135 phospholipids revealed that PlsEtn and PakCho significantly modulated phospholipid levels. Notably, PlsEtn modulated kidney overall phospholipids better than PakCho. Imaging the "space-content" of 9 phospholipids indicated that HFD significantly increased phospholipid content within the renal cortex. Furthermore, PlsEtn and PakCho significantly decreased the expression of transport-related proteins CD36, while elevating the expression of fatty acid ß-oxidation-related protein PPAR-α in the renal cortex. In conclusion, sea cucumber phospholipids reduced renal lipid accumulation, ameliorated renal damage, effectively regulated the content and distribution of renal phospholipids, and improved phospholipid homeostasis, exerting an anti-OGR effect.

[Material basis of kidney Yang deficiency rats before and after salt processing of Dipsacus asper based on spectrum-effect relationship].

This paper aims to study the spectrum-effect relationship between the fingerprints before and after salt processing of Dipsacus asper and the efficacy of warming and tonifying kidney Yang and find the main active components against kidney Yang deficiency before and after salt processing of D. asper, so as to provide the basis for clarifying the effect of salt processing on kidney Yang deficiency. The HPLC fingerprint before and after salt processing of D. asper was established by the HPLC-DAD. 15 common peaks were obtained, and 11 components were identified. The content changes of various components in rat serum were detected, and the difference in efficacy before and after salt processing was compared. The results of pharmacological experiments showed that salt processing of D. asper could enhance the kidney index. At the same dose, there was a significant difference between the raw D. asper and D. asper after salt processing groups. Compared with the model group, the contents of ACTH, cAMP, CORT, E_2, GH, Na~+-K~+-ATPase, T, and T4 in the serum of rats in the administration group increased to a certain extent, and the contents of cGMP and TNF-α decreased to a certain extent. Among them, there were significant differences in the above indexes in the serum of rats in the high-dose group of raw D. asper, middle-dose group of D. asper after salt processing, high-dose group of D. asper after salt processing, and the positive drug group. The overall results showed that D. asper after salt processing was more effective than raw D. asper in preventing kidney yang deficiency. The efficacy of D. asper was evaluated by grey correlation analysis, entropy method, and Pearson correlation analysis, and the components of D. asper after salt processing against kidney yang deficiency were screened out. According to the results of correlation degree ranking, the components with increased ranking before and after salt processing of D. asper were loganin, chlorogenic acid, dipsacoside A, asperosaponin Ⅵ, caffeic acid, and isochlorogenic acid B. It was preliminarily speculated that these compounds may be the potential pharmacodynamic components for the treatment of kidney yang deficiency before and after salt processing of D. asper. The changing components before and after the salt processing of D. asper were determined, which proved that D. asper after salt processing was superior to D. asper in the treatment of kidney yang deficiency. The spectrum-effect relationship between the efficacy of D. asper before and after salt processing and the treatment of kidney yang deficiency was established, which laid a foundation for the subsequent study on the pharmacodynamic components and molecular mechanism of salt processing of D. asper.

[Modified Fangji Huangqi Decoction alleviates renal interstitial fibrosis by inhibiting TGF-ß1/Smad/Snail signaling pathway during epithelial-mesenchymal transition].

This study investigated the effects of modified Fangji Huangqi Decoction on the expression of proteins related to epithelial-mesenchymal transition(EMT) in a mouse model of unilateral ureteral obstruction( UUO) and in a rat renal tubular epithelial cell(NRK-52E) model of fibrosis induced by transforming growth factor ß1(TGF-ß1). It aims to decipher the molecular mechanism by which modified Fangji Huangqi Decoction alleviates renal interstitial fibrosis. C57/BL mice were subjected to UUO.After the surgery, the mice were treated with 0. 5-fold and 2-fold concentrations of modified Fangji Huangqi Decoction and fosinopril sodium(positive control) for 7 days. The interstitial collagen deposition in the kidney was assessed by Masson staining. Western blot and RT-qPCR were employed to determine the expression levels of TGF-ß1, phosphorylated Smad2/3(p-Smad2/3), Smad2/3, Snail,epithelial cadherin(E-cadherin), alpha smooth muscle actin(α-SMA), and vimentin. The NRK-52E cell model induced by TGF-ß1was treated with the serum samples collected from SD rats treated with different concentrations of modified Fangji Huangqi Decoction.The CCK-8 assay was employed to examine the effects of the serum samples on NRK-52E cell proliferation. The cell morphology in different groups was observed under a microscope. Furthermore, the modeled cells were treated with the serum containing 1-fold decoction. Western blot and RT-qPCR were then employed to measure the expression levels of p-Smad2/3, Smad2/3, Snail,E-cadherin, α-SMA, and vimentin in the cells. Under the same conditions, sh RNA was used to silence the Snail gene, and measurements were repeated before and after treatment with the serum containing 1-fold decoction. The results indicated that modified Fangji Huangqi Decoction alleviated the fibrotic injury in the mouse model of UUO and the fibrosis in the NRK-52E cell model. The treatment with the decoction down-regulated the protein and m RNA levels of EMT-related indicators including p-Smad2/3, α-SMA,Snail, and vimentin, while it up-regulated the expression of E-cadherin. After sh RNA silencing of the Snail gene, the protein and m RNA levels of E-cadherin, α-SMA, and vimentin showed no significant differences before and after treatment with the serum containing the decoction. The results suggest that modified Fangji Huangqi Decoction may alleviate renal interstitial fibrosis by inhibiting the TGF-ß1/Smad/Snail signaling pathway and regulating the EMT process.

Point-of-Care Kidney and Genitourinary Ultrasound in Adults: Image Acquisition.

A range of conditions involving the kidneys and urinary bladder can cause organ-threatening complications that are preventable if diagnosed promptly with diagnostic imaging. Common imaging modalities include either computed tomography or diagnostic ultrasound. Traditionally, ultrasound of the kidney-genitourinary system has required consultative teams consisting of a sonographer performing image acquisition and a radiologist performing image interpretation. However, diagnostic point-of-care ultrasound (POCUS) has recently emerged as a useful tool to troubleshoot acute kidney injury at the bedside. Studies have shown that non-radiologists can be trained to perform diagnostic POCUS of the kidneys and bladder with high accuracy for a set number of important conditions. Currently, diagnostic POCUS of the kidney-genitourinary system remains underused in actual clinical practice. This is likely because image acquisition for this organ system is unfamiliar to most clinicians in specialties that encounter acute kidney injury, including primary care, emergency medicine, intensive care, anesthesiology, nephrology, and urology. To address this multi-specialty educational gap, this narrative review was developed by a multi-disciplinary group to provide a specialty-agnostic framework for kidney-genitourinary POCUS image acquisition: indications/contraindications, patient positioning, transducer selection, acquisition sequence, and exam limitations. Finally, we describe foundational concepts in kidney-genitourinary ultrasound image interpretation, including key abnormal findings that every bedside clinician performing this modality should know.

Mendelian Randomization Analysis of Systemic Iron Status and Risk of Different Types of Kidney Disease.

With rapid increases in incidence, diverse subtypes, and complicated etiologies, kidney disease remains a global public health problem. Iron, as an essential trace element, has pleiotropic effects on renal function and the progression of kidney diseases. A two-sample Mendelian randomization (MR) analysis was implemented to determine the potential causal effects between systemic iron status on different kidney diseases. Systemic iron status was represented by four iron-related biomarkers: serum iron, ferritin, transferrin saturation (TfSat), and total iron binding capacity (TIBC). For systemic iron status, 163,511, 246,139, 131,471, and 135,430 individuals were included in the genome-wide association study (GWAS) of serum iron, ferritin, TfSat, and TIBC, respectively. For kidney diseases, 653,143 individuals (15,658 cases and 637,485 controls), 657,076 individuals (8160 cases and 648,916 controls), and 659,320 individuals (10,404 cases and 648,916 controls) were included for immunoglobulin A nephropathy (IgAN), acute kidney disease (AKD), and chronic kidney disease (CKD), respectively. Our MR results showed that increased serum iron [odds ratio (OR): 1.10; 95% confidence interval (95% CI): 1.04, 1.16; p < 0.0042], ferritin (OR: 1.30; 95% CI: 1.14, 1.48; p < 0.0042), and TfSat (OR: 1.07; 95% CI: 1.04, 1.11; p < 0.0042)] and decreased TIBC (OR: 0.92; 95% CI: 0.88, 0.97; p < 0.0042) were associated with elevated IgAN risk. However, no significant associations were found between systemic iron status and AKD or CKD. In our MR study, the genetic evidence supports elevated systemic iron status as a causal effect on IgAN, which suggests a potential protective effect of iron chelation on IgAN patients.

The Role of Mitochondrial Sirtuins (SIRT3, SIRT4 and SIRT5) in Renal Cell Metabolism: Implication for Kidney Diseases.

Kidney diseases, including chronic kidney disease (CKD), diabetic nephropathy, and acute kidney injury (AKI), represent a significant global health burden. The kidneys are metabolically very active organs demanding a large amount of ATP. They are composed of highly specialized cell types in the glomerulus and subsequent tubular compartments which fine-tune metabolism to meet their numerous and diverse functions. Defective renal cell metabolism, including altered fatty acid oxidation or glycolysis, has been linked to both AKI and CKD. Mitochondria play a vital role in renal metabolism, and emerging research has identified mitochondrial sirtuins (SIRT3, SIRT4 and SIRT5) as key regulators of renal cell metabolic adaptation, especially SIRT3. Sirtuins belong to an evolutionarily conserved family of mainly NAD+-dependent deacetylases, deacylases, and ADP-ribosyl transferases. Their dependence on NAD+, used as a co-substrate, directly links their enzymatic activity to the metabolic status of the cell. In the kidney, SIRT3 has been described to play crucial roles in the regulation of mitochondrial function, and the antioxidative and antifibrotic response. SIRT3 has been found to be constantly downregulated in renal diseases. Genetic or pharmacologic upregulation of SIRT3 has also been associated with beneficial renal outcomes. Importantly, experimental pieces of evidence suggest that SIRT3 may act as an important energy sensor in renal cells by regulating the activity of key enzymes involved in metabolic adaptation. Activation of SIRT3 may thus represent an interesting strategy to ameliorate renal cell energetics. In this review, we discuss the roles of SIRT3 in lipid and glucose metabolism and in mediating a metabolic switch in a physiological and pathological context. Moreover, we highlight the emerging significance of other mitochondrial sirtuins, SIRT4 and SIRT5, in renal metabolism. Understanding the role of mitochondrial sirtuins in kidney diseases may also open new avenues for innovative and efficient therapeutic interventions and ultimately improve the management of renal injuries.

Effectiveness of edaravone in preventing contrast-induced nephropathy in high-risk patients undergoing coronary angiography: A randomized, double-blind trial.

Contrast-induced nephropathy (CIN) is a serious complication that occurs subsequent to the administration of contrast media for therapeutic angiographic interventions. As of present, no effective therapy exists to prevent its occurrence. This single-center double-blind randomized controlled trial aimed to evaluate the effect of edaravone, an antioxidant, in a group of high-risk patients undergoing coronary angiography. Ninety eligible patients with chronic kidney disease Stages 3-4 were randomly assigned to either the control group (n = 45) or the intervention group (n = 45). In the intervention group, one dosage of edaravone (60 mg) in 1 L of normal saline was infused via a peripheral vein 1 h prior to femoral artery-directed coronary angiography. Patients in the control group received an equal amount of infusion in their last hour before angiography. Both groups received intravenous hydration with 0.9% sodium 1 mL/kg/h starting 12 h before and continuing for 24 h after angiography. The primary outcome measure was the onset of CIN, defined as a 25% increase in serum creatinine levels 120 h after administration of contrast media. The occurrence of CIN was observed in 5.5% (n = 5) of the studied population: 2.2% of patients in the intervention group (n = 1) and 8.9% of controls (n = 4). However, this difference was not statistically significant. Administration of a single dosage of edaravone 1 h prior to infusion of contrast media led to a reduction in the incidence of CIN. Further investigations, employing larger sample sizes, are warranted to gain a comprehensive understanding of its efficacy.