Markers Of Renal Injury Research Articles

Dual Immunoglobulin Domain-Containing Cell Adhesion Molecule Increases Early in Renal Tubular Cell Injury and Plays Anti-Inflammatory Role.

Dual immunoglobulin domain-containing cell adhesion molecule (DICAM) is a type I transmembrane protein that presents in various cells including renal tubular cells. This study evaluated the expression and protective role of DICAM in renal tubular cell injury. HK-2 cells were incubated and treated with lipopolysaccharide (LPS, 30 μg/mL) or hydrogen peroxide (H2O2, 100 μM) for 24 h. To investigate the effect of the gene silencing of DICAM, small interfering RNA of DICAM was used. Additionally, to explain its role in cellular response to injury, DICAM was overexpressed using an adenoviral vector. DICAM protein expression levels significantly increased following treatment with LPS or H2O2 in HK-2 cells. In response to oxidative stress, DICAM showed an earlier increase (2-4 h following treatment) than neutrophil gelatinase-associated lipocalin (NGAL) (24 h following treatment). DICAM gene silencing increased the protein expression of inflammation-related markers, including IL-1β, TNF-α, NOX4, integrin β1, and integrin β3, in H2O2-induced HK-2 cell injury. Likewise, in the LPS-induced HK-2 cell injury, DICAM knockdown led to a decrease in occludin levels and an increase in integrin β3, IL-1β, and IL-6 levels. Furthermore, DICAM overexpression followed by LPS-induced HK-2 cell injury resulted in an increase in occludin levels and a decrease in integrin β1, integrin β3, TNF-α, IL-1β, and IL-6 levels, suggesting an alleviating effect on inflammatory responses. DICAM was elevated in the early stage of regular tubular cell injury and may protect against renal tubular injury through its anti-inflammatory properties. DICAM has a potential as an early diagnostic marker and therapeutic target for renal cell injury.

Early Renal Denervation Attenuates Cardiac Dysfunction in Heart Failure With Preserved Ejection Fraction.

The renal sympathetic nervous system modulates systemic blood pressure, cardiac performance, and renal function. Pathological increases in renal sympathetic nerve activity contribute to the pathogenesis of heart failure with preserved ejection fraction (HFpEF). We investigated the effects of renal sympathetic denervation performed at early or late stages of HFpEF progression. Male ZSF1 obese rats were subjected to radiofrequency renal denervation (RF-RDN) or sham procedure at either 8 weeks or 20 weeks of age and assessed for cardiovascular function, exercise capacity, and cardiorenal fibrosis. Renal norepinephrine and renal nerve tyrosine hydroxylase staining were performed to quantify denervation following RF-RDN. In addition, renal injury, oxidative stress, inflammation, and profibrotic biomarkers were evaluated to determine pathways associated with RDN. RF-RDN significantly reduced renal norepinephrine and tyrosine hydroxylase content in both study cohorts. RF-RDN therapy performed at 8 weeks of age attenuated cardiac dysfunction, reduced cardiorenal fibrosis, and improved endothelial-dependent vascular reactivity. These improvements were associated with reductions in renal injury markers, expression of renal NLR family pyrin domain containing 3/interleukin 1β, and expression of profibrotic mediators. RF-RDN failed to exert beneficial effects when administered in the 20-week-old HFpEF cohort. Our data demonstrate that early RF-RDN therapy protects against HFpEF disease progression in part due to the attenuation of renal fibrosis and inflammation. In contrast, the renoprotective and left ventricular functional improvements were lost when RF-RDN was performed in later HFpEF progression. These results suggest that RDN may be a viable treatment option for HFpEF during the early stages of this systemic inflammatory disease.

Does Hypertension Affect the Recovery of Renal Functions after Reversal of Unilateral Ureteric Obstruction?

Research has demonstrated that hypertension can lead to an exaggeration in the renal functional and histological changes caused by ureteral obstruction. These changes were particularly observed shortly after the release of a relatively brief period of unilateral ureteral obstruction (UUO). However, the long-term impact of hypertension on the recovery of renal functions has not been investigated beyond the immediate period after UUO reversal. In order to investigate this effect, a group of spontaneously hypertensive rats (G-SHR, n = 11) and a group of normotensive Wistar Kyoto rats (G-NTR, n = 11) were subjected to a 48 h reversible left UUO. The impact of UUO was then examined 45 days after the reversal of obstruction. The glomerular filtration rate, renal blood flow, and the fractional excretion of sodium in the post-obstructed left kidney (POK) showed similarities to the non-obstructed right kidney (NOK) in both groups. However, the changes in the albumin creatinine ratio, renal injury markers, pro-apoptotic markers, and histological changes in the G-SHR were much more pronounced compared to the G-NTR. We conclude that hypertension continues to have a significant impact on various aspects of renal injury and function, even several weeks after UUO reversal.

Higher Renal Net Acid Excretion, but Not Higher Phosphate Excretion, during Childhood and Adolescence Associates with the Circulating Renal Tubular Injury Marker Interleukin-18 in Adulthood.

High dietary phosphorus intake (P-In) and high acid loads may adversely affect kidney function. In animal models, excessive phosphorus intake causes renal injury, which, in humans, is also inducible by chronic metabolic acidosis. We thus examined whether habitually high P-In and endogenous acid production during childhood and adolescence may be early indicators of incipient renal inflammatory processes later in adulthood. P-In and acid-base status were longitudinally and exclusively determined by biomarker-based assessment in 277 healthy children, utilizing phosphate and net acid excretion (NAE) measurements in 24 h urine samples repeatedly collected between the ages of 3 and 17 years. Standard deviation scores (by sex and age) were calculated for anthropometric data and for the urinary biomarkers available within age range 3-17 years. Multivariable linear regression was used to analyze the relations of phosphate excretion and NAE with the adulthood outcome circulating interleukin-18 (IL-18), a marker of inflammation and kidney dysfunction. After adjusting for growth- and adulthood-related covariates and pro-inflammatory biomarkers to rule out confounding by non-renal inflammatory processes, regression models revealed a significant positive relationship of long-term NAE (p = 0.01), but not of long-term phosphate excretion with adult serum IL-18. Similar significant positive regression results were obtained after replacing NAE with 24 h urinary ammonium excretion as the exposition variable. Our results suggest that even moderate elevations in renal ammonia production, as caused by habitually higher acid loading during growth, may affect the intrarenal pro-inflammatory system in the long-term, known to be boosted by acidosis-induced raised ammoniagenesis.

Effect of a Combination of Citric Acid and Selenium Nanoparticles on Male Rats Nephrotoxicity Caused by Carbon Tetrachloride

Background: To investigate the therapeutic effects of a combination of citric acid and Se-NPs against carbon tetrachloride (CCl4)-induced renal damage in rats. Methods: Twenty-four rats were divided into three groups (n = 8 each). Group 1 (control) received the vehicle, while Group 2 received a single dose of 1 ml/kg CCl4 in liquid paraffin (1:1 volume) via intraperitoneal injection. Group 3 was administered a single dose of 1 ml/kg CCl4 in liquid paraffin and then treated twice a week for three weeks with a dose of 2.5 mg/kg Se-NPs. One-way ANOVA and Tukey’s method were used to compare the overall effects of each treatment. Result: CCL4 elevated MDA levels and decreased GSH levels in group 2 animals compared with those in the control group. Se-NPs significantly restored the oxidative stability in group 3. We found that CCL4 significantly increased its effect on renal function, whereas Se-NPs restored the renal structure affected by CCL4. As a result, Se-NPs can potentially reduce the markers of renal injury caused by CCl4, while also restoring oxidative stability and renal structure and function.

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.

Single-cell sequencing dissects the transcriptional identity of activated fibroblasts and identifies novel persistent distal tubular injury patterns in kidney fibrosis

Examining kidney fibrosis is crucial for mechanistic understanding and developing targeted strategies against chronic kidney disease (CKD). Persistent fibroblast activation and tubular epithelial cell (TEC) injury are key CKD contributors. However, cellular and transcriptional landscapes of CKD and specific activated kidney fibroblast clusters remain elusive. Here, we analyzed single cell transcriptomic profiles of two clinically relevant kidney fibrosis models which induced robust kidney parenchymal remodeling. We dissected the molecular and cellular landscapes of kidney stroma and newly identified three distinctive fibroblast clusters with “secretory”, “contractile” and “vascular” transcriptional enrichments. Also, both injuries generated failed repair TECs (frTECs) characterized by decline of mature epithelial markers and elevation of stromal and injury markers. Notably, frTECs shared transcriptional identity with distal nephron segments of the embryonic kidney. Moreover, we identified that both models exhibited robust and previously unrecognized distal spatial pattern of TEC injury, outlined by persistent elevation of renal TEC injury markers including Krt8 and Vcam1, while the surviving proximal tubules (PTs) showed restored transcriptional signature. We also found that long-term kidney injuries activated a prominent nephrogenic signature, including Sox4 and Hox gene elevation, which prevailed in the distal tubular segments. Our findings might advance understanding of and targeted intervention in fibrotic kidney disease.

Improved pregnancy outcome in gestational diabetes mellitus patients treated with insulin aspart and metformin: a comparative study.

To investigate the impact of combining metformin with insulin aspart on blood glucose control, renal injury, and pregnancy outcome in gestational diabetes mellitus (GDM) patients. In this retrospective analysis, the clinical data of 140 GDM patients treated at Baoji Maternal and Child Health Hospital between March 2020 and March 2022 were studied. The patients were divided into a control group (insulin aspart alone, n=64) and an observation group (combination of insulin aspart and metformin, n=76) according to their treatment regimen. The blood glucose metabolism, renal injury markers, and pregnancy outcomes between the two groups were assessed and compared. The observation group demonstrated significantly lower levels of blood glucose metabolism markers (fasting plasma glucose [FPG], fasting insulin [FINS], mean amplitude of glycemic excursions [MAGE], and mean of daily differences [MODD]), renal injury indicators (microalbuminuria [mAlb], serum cystatin C [CysC], free fatty acids [FFA], and neutrophil gelatinase-associated lipocalin [NGAL]), and inflammatory markers (interleukin-6 [IL-6], transforming growth factor-β1 [TGF-β1], and lipoprotein-associated phospholipase A2 [Lp-PLA2]) compared to the control group (all P<0.05). Additionally, the incidence of adverse pregnancy outcomes in both newborns and mothers was lower in the observation group (P<0.05). Logistic regression analysis identified the treatment regimen, patient age, and pre-pregnancy BMI as independent risk factors for adverse pregnancy outcome. The combination of metformin and insulin aspart in treating GDM can effectively reduce blood glucose levels, mitigate renal injury, and improve pregnancy outcome. This treatment approach presents a viable option for optimizing maternal and fetal health in GDM cases.

Mitigative role of cysteamine against unilateral renal reperfusion injury in Wistar rats.

Ischemia-reperfusion injury (IRI) is unavoidable during kidney transplant and it is responsible for delayed or non-function after kidney transplantation. Cysteamine is the standard drug in the management of nephropathic cystinosis and its extra-renal complications. Thus, we designed this study to investigate its potential against renal reperfusion injury. Significant elevation of H2O2, MDA, and nitrite and reduced GPx, GSH, and protein thiol in the Ischemia-reperfusion injury rats was reversed by cysteamine (50 and 100mg/kg). Serum MPO, TNF-α, IL-1β, creatinine, and AOPP were significantly elevated in IRI while rats treated with cysteamine revealed a significant decrease (p < 0.05) in the activities of these pro-inflammatory and renal injury markers. Based on its activity against inflammation, apoptosis, and free radical-induced stress, cysteamine has great potential to be used as a kidney transplant pre-operative drug to prevent renal reperfusion injury.

Association of high vibration perception threshold with reduced renal function in patients with type 2 diabetes.

To investigate the correlation between vibration sensory threshold (VPT) and renal function, including glomerulus and renal tubule, in patients with type 2 diabetes mellitus (T2DM). A total of 1274 patients with T2DM who were enrolled in the Department of Endocrinology of the First Affiliated Hospital of Fujian Medical University between January 2017 and June 2020 were included. Patients were grouped according to VPT levels and divided into three groups, including the normal VPT group (VPT<15V), the mild-moderate elevated VPT group (VPT15~25V), and the severely elevated VPT group (VPT≥25 V). Linear correlation analysis was used to analyze the correlation between VPT and renal functions, including glomerulus markers urine microalbumin (MA) and urinary immunoglobulin G (U-IgG), and renal tubule marker α1-microglobulin (α1-MG). Chronic kidney disease (CKD) was defined according to Kidney Disease Improving Global Outcomes (KDIGO) criteria. The binary logistic regression of the relation between VPT and CKD, eGFR<60 ml/min, and UACR >30 mg/g were expressed. In the mild-moderate and severely elevated VPT group, injury biomarkers of glomerulus (MA and U-IgG), renal tubule (α1-MG), and the incidence of CKD, eGFR<60 ml/min, and UACR > 30 mg/g were gradually increased compared with the normal VPT group. Furthermore, patients with diabetes and severely elevated VPT had significantly higher levels of MA (β=197.54, p=0.042) and α1-MG (β=11.69, p=0.023) compared to those with normal VPT. Also, patients with mild-moderate elevated VPT demonstrate significantly higher levels of MA (β=229.02, p=0.005). Patients in mild-moderate elevated VPT group (OR=1.463, 95% CI 1.005-2.127; OR=1.816, 95% CI 1.212-2.721) and severely elevated VPT group (OR=1.704, 95% CI 1.113-2.611; OR=2.027, 95% CI 1.248-3.294) are at a higher incidence of CKD and elevated levels of UACR>30mg/g compared to those in the VPT normal group. Moreover, the incidence of positive Upro was notably higher in the severely elevated VPT group (OR=1.738, 95% CI 1.182-2.556). However, this phenomenon was not observed in the incidence of eGFR <60 ml/min. A higher VPT is positively associated with the incidence of CKD in patients with T2DM, particularly with elevated UACR. VPT may serve as a marker for glomerulus and renal tubule injury.

CCR2 antagonist attenuates calcium oxalate-induced kidney oxidative stress and inflammation by regulating macrophage activation.

C-C chemokine receptor type 2 (CCR2) is a monocyte chemokine associated with oxidative stress and inflammation. Kidney stones (KS) are composed of calcium oxalate (CaOx), which trigger renal oxidative stress and inflammatory. This study aims to evaluate the effects of CCR2 on KS in vivo and in vitro. Eight-week-old male C57BL/6J mice were intraperitoneally injected with glyoxylate (GOX) daily to establish a KS model, and along with CCR2 antagonist (INCB3344) treatment on days 2, 4, and 6. The results showed that CCR2 antagonist reduced renal injury markers (blood urea nitrogen and serum creatinine), alleviated renal tubular injury and CaOx crystal deposition. CCR2 antagonist also decreased CCR2 expression induced by GOX treatment and increased Nrf2 expression. GOX treatment promoted malondialdehyde (MDA) production, decreased glutathione (GSH) content, and inhibited catalase (CAT) and superoxide dismutase (SOD) activity, however, CCR2 antagonist attenuated the above effects of GOX. CCR2 antagonist had inhibitory effects on GOX-induced inflammatory cytokine expression (IL1B, IL6 and MCP1), and inhibited apoptosis by increasing Bcl-2 expression and decreasing Bax and cleaved-caspase 3 expression. In vitro experiments were performed by co-culture model of CaOx-induced damaged HK-2 cells and macrophage-like THP-1 cells. CCR2 antagonist inhibited CaOx-induced THP-1 cell M1 polarization by decreasing the TNF-α, IL6 and iNOS levels, and further alleviated CaOx-induced oxidative stress damage, inflammatory response and apoptosis of HK-2 cells. The study suggests that CCR2 antagonist may be resistant to CaOx crystals-induced oxidative stress and inflammation by inhibiting macrophage M1 polarization.

Imperatorin ameliorates kidney injury in diabetic mice by regulating the TGF-β/Smad2/3 signaling axis, epithelial-to-mesenchymal transition, and renal inflammation

Diabetic nephropathy (DN) is a serious concern in patients with diabetes mellitus. Prolonged hyperglycemia induces oxidative damage, chronic inflammation, and build-up of extracellular matrix (ECM) components in the renal cells, leading to kidney structural and functional changes. Imperatorin (IMP) is a naturally occurring furanocoumarin derivative with proven antioxidative and anti-inflammatory properties. We investigated whether IMP could improve DN and employed high glucose (HG)-induced HK-2 cells and high-fat diet-fed streptozotocin (HFD/STZ)-generated DN experimental model in C57BL/6 J mice. In vitro, IMP effectively reduced the HG-activated reactive oxygen species generation, disturbance in the mitochondrial membrane potential (MMP) and epithelial-to-mesenchymal transition (EMT)-related markers, and the transforming growth factor (TGF)-β and collagen 1 expression in HK-2 cells. In vivo, we found an elevation of serum creatinine, kidney histology alterations, and collagen build-up in the kidneys of the DN control group. Also, we found that altered expression of EMT-related markers, upregulation of the TGF-β/Smad2/3 axis, and elevated pro-inflammatory molecules, TNF-α, IL-1β, IL-18 and phospho–NF–kB (p65) in the DN control group. IMP treatment did not significantly reduce the blood glucose level compared to the DN control group. However, IMP treatment effectively improved renal damage by ameliorating kidney histological changes and serum renal injury markers. IMP treatment restored renal antioxidants and exhibited anti-inflammatory effects in the kidneys. Moreover, the abnormal manifestation of EMT-related attributes and elevated levels of TGF-β, phospho-Smad2/3, and collagen 1 were also normalized in the IMP treatment group. Our findings highlight that IMP may be a potential candidate for treating DN.

Novel renal injury markers in dogs with ehrlichiosis

Canine monocytic ehrlichiosis (CME) has been observed to impact renal function. Currently, the recognition of acute kidney injury is through the nonspecific biomarker serum creatinine (sCr). Novel markers of renal injury such as urinary clusterin (uClust) and urinary cystatin B (uCysB) may increase our understanding of the relationship between ehrlichiosis and renal cellular injury. The aim of this study was to evaluate novel renal injury biomarkers in dogs with acute CME. Twenty healthy dogs were enrolled in the control group (CG), and 16 dogs naturally infected with Ehrlichia canis were included in the Ehrlichia Group (EG). All dogs were followed for 45 days. EG dogs were treated with doxycycline twice daily for the first 30 days. Urine and serum were collected at: 0, 0.5, 1, 15, 30, and 45 days after start of treatment. Urine concentrations of uClust and uCysB were determined using a research ELISA immunoassay. A linear mixed model was used to estimate population mean of renal injury markers with patient as the random effect, and day and treatment as fixed effects. EG was observed to have higher uClust values compared to CG (estimated population mean EG: 213 ng/dL vs. CG: 84 ng/dL, P &lt; 0.001). EG was observed to have higher uCysB values compared to CG (estimated population mean EG: 248 ng/dL vs. CG: 38 ng/dL, P &lt; 0.001). Increases in uCysB and uClust suggest the presence of renal injury and a possible mechanism for the observed predisposition to chronic kidney disease in dogs with ehrlichiosis.

Serum Uric Acid to Creatinine Ratio with Estimated Glomerular Filtration Rate in Type 2 Diabetes Patients.

Diabetes mellitus is a metabolic disorder associated with cardiovascular and renal complications. The serum uric acid to creatinine ratio and estimated glomerular filtration rate are important markers used to assess kidney function in patients with type 2 diabetes. This study aimed to find the correlation between serum uric acid to creatinine ratio and estimated glomerular filtration rate to various parameters among the diabetes patients. It is an observational hospital-based, cross-sectional study. Patients with a diagnosis of diabetes for three years or more duration were selected. This study designed to serum uric acid to creatinine ratio with estimated glomerular filtration rate and its relationship with other biochemical parameters. The Modification of Diet in Renal Disease formula was used to calculate estimated glomerular filtration rate (eGFR). eGFR (mL/min∙1.73 m2) = 186 × (Scr) -1.154 × (age) - 0.203 × (0.742 female). Low eGFR was defined as eGFR<60 mL/min∙1.73 m2. The data were analyzed by SPSS version 20. Mean values of different variables, standard deviations and p-values were calculated. Mean serum uric acid to creatinine ratio was 6.09±1.71 and elevated among 49.1%. Mean blood urea and serum creatinine levels were 28.0±10.72 and 1.01±0.18, respectively. There was a significant positive correlation between eGFR and serum uric acid : serum creatinine ( r = 0.246, p = 0.007) in this study. The serum uric acid to creatinine ratio can serve as an early marker for renal injury, showing a positive correlation with estimated glomerular filtration rate (eGFR). Monitoring serum uric acid to creatinine ratio levels alongside eGFR can assistance in the identification and management of kidney damage in its early stages.

Long wavelength light exposure reduces systemic inflammation coagulopathy and acute organ injury following multiple injuries in mice.

Evidence suggests that variation in light exposure strongly influences the dynamic of inflammation, coagulation, and the immune system. Multiple injuries induce systemic inflammation that can lead to end-organ injury. Here, we hypothesize that alterations in light exposure influence posttrauma inflammation, coagulopathy, and end-organ injury. C57BL/6 mice underwent a validated multiple-injury and hemorrhage model performed following 72 hours of exposure to red (617 nm, 1,700 lux), blue (321 nm, 1,700 lux), and fluorescent white light (300 lux) (n = 6-8/group). The animals were sacrificed at 6 hours posttrauma. Plasma samples were evaluated and compared for proinflammatory cytokine expression levels, coagulation parameters, markers of liver and renal injury, and histological changes (Carstairs staining). One-way analysis of variance statistical tests were applied to compare study groups. Preexposure to long-wavelength red light significantly reduced the inflammatory response at 6 hours after multiple injuries compared with blue and ambient light, as evidenced by decreased levels of interleukin 6, monocyte chemoattractant protein-1 (both p < 0.001), liver injury markers (alanine transaminase, p < 0.05), and kidney injury markers (cystatin C, p < 0.01). In addition, Carstairs staining of organ tissues revealed milder histological changes in the red light-exposed group, indicating reduced end-organ damage. Furthermore, prothrombin time was significantly lower ( p < 0.001), and fibrinogen levels were better maintained ( p < 0.01) in the red light-exposed mice compared with those exposed to blue and ambient light. Prophylactic light exposure can be optimized to reduce systemic inflammation and coagulopathy and minimize acute organ injury following multiple injuries. Understanding the mechanisms by which light exposure attenuates inflammation may provide a novel strategy to reducing trauma-related morbidity.

Klotho activation of Nrf2 inhibits the ferroptosis signaling pathway to ameliorate sepsis-associated acute kidney injury.

Sepsis-associated acute kidney injury (SA-AKI) is a common complication of sepsis and greatly increases patient mortality. Recombinant human Klotho protein (Klotho) is a protective protein that can be secreted by the kidney. The aim of this study was to explore the protective effect of Klotho on SA-AKI and its molecular mechanism. In vivo, a mouse SA-AKI model was constructed by cecum ligation perforation (CLP). In vitro, a human renal tubular cell epithelial cell line (HK2) was induced with lipopolysaccharide (LPS) in the SA-AKI model. Determine renal injury markers, inflammatory factors, oxidative stress and molecular proteins related to the ferroptosis signaling pathway. Klotho reduced the release of renal injury markers and inflammatory cytokines, decreased oxidative stress, improved renal histopathological changes, ameliorated mitochondrial damage in mouse renal tubular epithelial cells, increased HK2 cell viability and reduced reactive oxygen species (ROS) accumulation. Exogenous supplementation with Klotho increased the Klotho content in circulating blood, renal tissue and HK2 cells. In the SA-AKI model, Klotho attenuated renal tissue injury, increased HK2 cell viability, decreased inflammatory factor expression and oxidative stress, restored tubular epithelial mitochondrial function, and increased its level in circulating blood, renal tissue and HK2 cells. Klotho probably exerts its protective effects by activating Nrf2 to inhibit the ferroptosis signaling pathway.

Tweak/Fn14 system is involved in rhabdomyolysis-induced acute kidney injury

BackgroundRhabdomyolysis is a severe clinical syndrome associated to acute kidney injury (AKI) and chronic kidney disease (CKD). TWEAK/Fn14 signaling axis regulates renal inflammation and tubular cell death. However, the functional role of TWEAK/Fn14 in rhabdomyolysis remains unknown. MethodsRhabdomyolysis was induced in wild-type, TWEAK- and Fn14-deficient mice or mice treated with TWEAK blocking antibody. Renal injury, inflammation, fibrosis and cell death were assessed. Additionally, we performed in vivo and in vitro studies to explore the possible signalling pathways involved in Fn14 regulation. FindingsFn14 renal expression was increased in mice with rhabdomyolysis, correlating with decline of renal function. Mechanistically, myoglobin (Mb) induced Fn14 expression via ERK and p38 pathway, whereas Nrf2 activation diminished Mb-mediated Fn14 upregulation in cultured renal cells. TWEAK or Fn14 genetic depletion ameliorated rhabdomyolysis-associated loss of renal function, histological damage, tubular cell death, inflammation, and expression of both tubular and endothelial injury markers. Deficiency of TWEAK or Fn14 also decreased long-term renal inflammation and fibrosis in mice with rhabdomyolysis. Finally, pharmacological treatment with a blocking TWEAK antibody diminished the expression of acute renal injury markers and cell death and lessened residual kidney fibrosis and chronic inflammation in rhabdomyolysis. InterpretationTWEAK/Fn14 axis participates in the pathogenesis of rhabdomyolysis-AKI and subsequent AKI-CKD transition. Blockade of this signaling pathway may represent a promising therapeutic strategy for reducing rhabdomyolysis-mediated renal injury. FundingSpanish Ministry of Science and Innovation, ISCIII and Junta de Andalucía.

Circulating extracellular vesicles in human cardiorenal syndrome promote renal injury in a kidney-on-chip system.

BACKGROUNDCardiorenal syndrome (CRS) - renal injury during heart failure (HF) - is linked to high morbidity. Whether circulating extracellular vesicles (EVs) and their RNA cargo directly impact its pathogenesis remains unclear.METHODSWe investigated the role of circulating EVs from patients with CRS on renal epithelial/endothelial cells using a microfluidic kidney-on-chip (KOC) model. The small RNA cargo of circulating EVs was regressed against serum creatinine to prioritize subsets of functionally relevant EV-miRNAs and their mRNA targets investigated using in silico pathway analysis, human genetics, and interrogation of expression in the KOC model and in renal tissue. The functional effects of EV-RNAs on kidney epithelial cells were experimentally validated.RESULTSRenal epithelial and endothelial cells in the KOC model exhibited uptake of EVs from patients with HF. HF-CRS EVs led to higher expression of renal injury markers (IL18, LCN2, HAVCR1) relative to non-CRS EVs. A total of 15 EV-miRNAs were associated with creatinine, targeting 1,143 gene targets specifying pathways relevant to renal injury, including TGF-β and AMPK signaling. We observed directionally consistent changes in the expression of TGF-β pathway members (BMP6, FST, TIMP3) in the KOC model exposed to CRS EVs, which were validated in epithelial cells treated with corresponding inhibitors and mimics of miRNAs. A similar trend was observed in renal tissue with kidney injury. Mendelian randomization suggested a role for FST in renal function.CONCLUSIONPlasma EVs in patients with CRS elicit adverse transcriptional and phenotypic responses in a KOC model by regulating biologically relevant pathways, suggesting a role for EVs in CRS.TRIAL REGISTRATIONClinicalTrials.gov NCT03345446.FUNDINGAmerican Heart Association (AHA) (SFRN16SFRN31280008); National Heart, Lung, and Blood Institute (1R35HL150807-01); National Center for Advancing Translational Sciences (UH3 TR002878); and AHA (23CDA1045944).

Correlation between Neutrophil gelatinase-associated lipocalin and ß2-Microglobulin with serum protein electrophoresis in multiple myeloma patients

Objective: To find the correlation between neutrophil gelatinase-associated lipocalin and beta2-microglobulin inpatients with multiple myeloma.Method: The case-control study was conducted from November 2021 to March 2022, after approval from ethics reviewcommittees of three major medical establishments in Baghdad, Iraq. There were randomly selected multiple myelomapatients of either gender with normal concentration of urea and creatinine in group A, multiple myeloma patients ofeither gender with increased concentration of urea and creatinine in group B and healthy controls in group C.Neutrophil gelatinase-associated lipocalin and beta2-microglobulin were assessed using enzyme-linkedimmunosorbent assay technique. Data was analysed using SPSS 26.Results: Of the 180 subjects, there were 60(33.3%) in each of the 3 groups, with each group having 40(66.5%) malesand 20(33.3%) females, and overall age ranging 40-79 years. Protein electrophoresis in group A patients wassignificantly higher (p=0.001) in alpha1, beta and gamma globulin. Among group B patients, a highly significantincrease (p=0.001) was noted in alpha1, alpha2, beta and gamma globulin. Beta2-microglobulin was a more sensitiveand specific marker for renal injury than neutrophil gelatinase-associated lipocalin in myeloma patients(p&lt;0.05).Conclusion: Beta2-microglobulin and neutrophil gelatinase-associated lipocalin were both more sensitive markersthan serum urea and creatinine in the diagnosis of acute kidney injury in multiple myeloma patients.Keywords: Lipocalin, Creatinine, Multiple myeloma, Microglobulin, Urea, Electrophoresis, Globulins, Albumins,Enzyme, Immunosorbent assay, Kidney injury.

OR35-02 Novel Androgen Receptor PROTAC Degrader ARV-110 Ameliorates Androgen Mediated Renal Injury in a Mouse Model of Polycystic Ovary Syndrome

Abstract Disclosure: J. Basnet: None. S. Rezq: None. A.M. Huffman: None. T.E. Asala: None. L.L. Yanes Cardozo: None. D.G. Romero: None. Background: Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in reproductive-age women. PCOS women often have increased central adiposity, insulin resistance, and renal injury. Hyperandrogenism is prevalent in PCOS women and is associated with renal injury and dysfunction. Androgens bind to the androgen receptor (AR) to impart downstream transcriptional activity. Targeting the AR may alleviate PCOS complications; however, the use of AR blockers is limited by their severe adverse effects in females; thus, safer alternative approaches are highly needed. The novel AR Proteolysis Targeting Chimera (PROTAC) degrader ARV-110 has shown high efficacy to prevent AR signaling in prostate cancer; however, its efficacy in PCOS is unknown. Using a well-established hyperandrogenemic mouse model of PCOS, we aim to test the hypothesis that decreasing AR protein levels with ARV-110 ameliorates androgen-mediated derangements in PCOS. Methods: Three-week old female mice (C57BL/6N) were implanted with Silastic tubes filled with the androgen dihydrotestosterone (DHT, 8mg, s.c., 90 days) or vehicle (n=6/grp). Four weeks post-DHT administration, mice were treated with ARV-110 (1 mg/kg/day, s.c.) for an additional 8 weeks. Body composition (EchoMRI) and oral glucose tolerance test (OGTT) were assessed. Kidney weight was measured by gravimetry. AR, extracellular matrix (ECM) remodeling marker MMP9, pro-fibrotic marker TGF-β, renal injury markers (urinary albumin to creatinine ration (UACR), KIM1, and NGAL) were assessed by Western-blot or ELISA. Results: DHT mice showed significant (p&amp;lt;0.05) increases in body weight (27.3±0.6 vs 23.9±0.26 g), fat mass (4.2±0.6 vs 2.1±0.1 g), lean mass (21.6±0.2 vs 19.8±0.2 g), as well as kidney weight (491.3±7.69 vs 303.1±5.5 mg) compared to controls. DHT increased fasting glucose (183.2±25.2 vs 141.5±9.9 mg/dL, p&amp;lt;0.05) and impaired OGTT (AUC:34557±6255 vs 23459±1896 mg.min/dL, p&amp;lt;0.05). ARV-110 treatment ameliorated all aforementioned DHT-mediated changes. At the molecular level, DHT-treated mice had higher renal AR (2.5-fold) and MMP9 (1.5-fold) protein expression. DHT upregulated renal TGF-β levels (2-fold, p&amp;lt;0.05), UACR (966.8±160.9 vs 381.5±41.2 ng albumin/mg creatinine), and urinary KIM1 (3.5-fold) and NGAL (6-fold). ARV-110 successfully decreased renal AR protein levels by 70% in DHT mice compared to vehicle-treated DHT. Excitingly, while ARV-110 did not modulate renal TGF-β levels, it completely abolished DHT-mediated increase in renal MMP9 while significantly lowering the levels of urinary renal injury markers UACR, KIM1 and NGAL. Conclusion and significance: Our findings suggest that DHT-mediated kidney hypertrophy, associated ECM remodeling and injury are ameliorated by ARV-110 in DHT-treated mice. AR PROTACs could be a novel therapeutic approach to treat renal dysfunction in PCOS. Supported by NIH P20GM121334. Presentation Date: Sunday, June 18, 2023