Kidney Inflammation Research Articles

Mitigation of hypobaric hypoxia induced renal inflammatory alterations by quercetin prophylaxis

The objective of the present study is to decipher the role of NF-κB and its associated downstream genes involved in causing inflammation in kidneys of rats under acute hypobaric hypoxia exposure. The study also aims at finding out the efficacy of quercetin in comparison with dexamethasone in prevention of hypobaric hypoxia induced renal inflammation. Sprague Dawley (SD) rats (n = 6) were preconditioned with 50 mg/Kg BW of quercetin, 1 h prior to hypobaric hypoxia exposure (12 h). The results revealed a significant increase in reactive oxygen species (ROS) generation and malondialdehyde (MDA) (p < 0.001) levels along with down regulation of GPx and SOD levels in kidney tissue of hypobaric hypoxia exposed rats as compared to control. However, ROS production and MDA levels in kidney tissues were reduced significantly (p < 0.001) with enhanced antioxidant enzyme levels (GPx and SOD) in rats fed with quercetin as compared to hypobaric hypoxia exposed control (p < 0.001). Protein expression analysis through western blotting and EMSA performed in nuclear extracts of kidneys, exhibited a significant upregulation of NF-κB under hypobaric hypoxic stress as compared to control. Whereas pretreatment with quercetin aids in downregulation of NF-κB expression in kidneys of rats as compared to the hypobaric hypoxia exposed group. Further, quercetin prophylaxis significantly reduced the expression of pro-inflammatory cytokines (TNF-α, IL-2 and IL-6), increased the anti-inflammatory cytokines (IL-10, IL-4 and TGF-β) along with reduced expression of cell adhesion molecules (ICAM-1, VCAM-1, E-selectin and P-selectin) in kidneys of rats under hypobaric hypoxia as compared to hypobaric hypoxia control. However, pre-treatment with dexamethasone was not as effective as quercetin, in controlling the renal inflammation. Furthermore, improved hematological parameters such as WBC, RBC, and platelet count indicated that quercetin is a well-functioning effective molecule under hypobaric hypoxic exposure. The histopathological and TEM findings, manifested the structural changes in tubular arrangements in kidneys of rats, and these changes were found to be modified by quercetin prophylaxis under hypobaric hypoxic stress. Hence, the present study indicates that, quercetin can be considered as a potential phytochemical flavonoid moiety in preventing the acute renal inflammation under hypobaric hypoxia.

Investigating the indirect therapeutic effect of hAMSCs utilizing a novel scaffold (PGS-co-PCL/PGC/PPy/Gelatin) in myocardial ischemia-reperfusion-induced renal failure in male Wistar rats

BackgroundMyocardial ischemia-reperfusion (MI/R) occurs due to temporary or permanent interruptions in the coronary and circulatory system, indirectly affecting kidney function through reduced cardiac output for metabolic needs. In this study, the aim was to explore the indirect effects of using human amniotic membrane mesenchymal stem cells (hAMSCs) with the PGS-co-PCL/PGC/PPy/Gelatin scaffold in male rats with renal failure induced by miocardial ischemia-reperfusion. MethodsMI/R injury was induced in 48 male Wistar rats through left anterior descending artery ligation, divided into four groups (n=12); control group, cell group, scaffold group, and celss+scaffold group. Evaluations were conducted at two and thirty days post MI/R injury, encompassing echocardiography, biochemical, inflammatory markers analysis, and histological assessment. ResultsEchocardiographic findings exhibited notable enhancement in ejection fraction, fractional shortening, and stroke volume of treated groups compared to controls after 30 days (P< 0.05). Serum creatinine (P< 0.001) and urea (P< 0.05) levels significantly decreased in the scaffold+cells group) compared to the control group. The treated cells+ scaffold group displayed improved kidney structure, evidenced by larger glomeruli and reduced Bowman's space compared to the control group (P< 0.01). Immunohistochemical analysis indicated reduced TNF-α protein in the scaffold+ cells group (P< 0.05) in contrast to the control group (P< 0.05). Inflammatory factors IL-6, TNF-α, and AKT gene expression in renal tissues were improved in scaffold+ cells-treated animals. ConclusionOur research proposes the combination of hAMSCs and the PGS-co-PCL/PGC/PPy/Gelatin scaffold in MI/R injured rats appears to enhance renal function and reduce kidney inflammation by improving cardiac output.

Lycopene Protects against Atrazine-Induced Kidney STING-Dependent PANoptosis through Stabilizing mtDNA via Interaction with Sam50/PHB1.

Atrazine (ATR) is a widely used herbicide worldwide that can cause kidney damage in humans and animals by accumulation in water and soil. Lycopene (LYC), a carotenoid with numerous biological activities, plays an important role in kidney protection due to its potent antioxidant and anti-inflammatory effects. The current study sought to investigate the role of interactions between mtDNA and the cGAS-STING signaling pathway in LYC mitigating PANoptosis and inflammation in kidneys induced by ATR exposure. In our research, 350 mice were orally administered LYC (5 mg/kg BW/day) and ATR (50 or 200 mg/kg BW/day) for 21 days. Our results reveal that ATR exposure induces a decrease in mtDNA stability, resulting in the release of mtDNA into the cytoplasm through the mPTP pore and the BAX pore and the mobilization of the cGAS-STING pathway, thereby inducing renal PANoptosis and inflammation. LYC can inhibit the above changes caused by ATR. In conclusion, LYC inhibited ATR exposure-induced histopathological changes, renal PANoptosis, and inflammation by inhibiting the cGAS-STING pathway. Our results demonstrate the positive role of LYC in ATR-induced renal injury and provide a new therapeutic target for treating renal diseases in the clinic.

Aromadendrin alleviates LPS-induced kidney apoptosis and inflammation by inhibiting phosphorylation of MAPK and NF-κB signaling pathways.

Excessive inflammation and apoptosis in kidneys are critical players in the pathogenesis of acute kidney injury (AKI). Aromadendrin is a natural flavonoid characterized by anti-inflammatory, anti-apoptotic, and antioxidant actions. Thus, we investigated the roles and mechanisms of aromadendrin in the development of AKI. Lipopolysaccharide (LPS) was used to induce AKI mice, and one hour after LPS challenge, the mice received oral administration of aromadendrin or vehicle. Renal functions were assessed by measuring blood urea nitrogen and creatinine in serum. Histological changes were determined by hematoxylin and eosin staining. Apoptotic cells of renal tissues were detected by TUNEL staining. Gene expression was measured by western blotting and RT-qPCR. Aromadendrin alleviated LPS-induced renal dysfunctions and histological defects in mice. Additionally, aromadendrin suppressed excessive inflammation and tissue apoptosis in the kidneys of LPS-induced AKI mice. Mechanistically, aromadendrin blocked the activation of NF-κB and MAPK pathways in LPS-induced AKI mice. Aromadendrin alleviates LPS-stimulated inflammation and tissue cell apoptosis in kidneys by inactivating the NF-κB and MAPK pathways.

A Potential Anti-inflammatory Effect of Ertugliflozin in Animal Model

Background: Acute kidney injury (AKI) accounts for up to 60% of hospitalized patients in intensive care units and is a widespread diagnosis. Recent years have seen an increase in risk factors for it, including old age, chronic diabetes, and kidney disease (CKD). The definition of acute kidney injury (AKI), formerly known as acute renal failure, is a rapid decrease in the glomerular filtration rate. Nephrotoxicity is mainly caused by drugs and auto-immune-induced kidney injury, which is defined by immune cell infiltration in the tubulointerstitial. Interleukin-1B (IL-1B) and tumor necrosis factor-alpha (TNF-α) are signs of kidney inflammation. Objective: Evaluate the Anti-inflammatory effect of ertugliflozin. Materials &amp; Methods: Thirty adult male albino rats were recruited. These rats were raised in an animal house with a special commercial diet and water. After ten days of acclimatization, the selected rats were separated at random into three groups. Each experimental group consisted of ten rats. This study ran from December 18, 2023, to January 1, 2024, and was carried out in the Animal House of the College of Medicine/University of Babylon. Serum samples were taken for measuring IL-1B and TNF-α. Result: The results demonstrated that ertugliflozin provides anti-inflammatory in the treated groups. The two parameters manifest it. Conclusion: The results emphasize that ertugliflozin has an anti-inflammatory effect.

Signaling through cAMP-Epac1 induces metabolic reprogramming to protect podocytes in glomerulonephritis

Unlike classical protein kinase A, with separate catalytic and regulatory subunits, EPACs are single chain multi-domain proteins containing both catalytic and regulatory elements. The importance of cAMP-Epac-signaling as an energy provider has emerged over the last years. However, little is known about Epac1 signaling in chronic kidney disease. Here, we examined the role of Epac1 during the progression of glomerulonephritis (GN). We first observed that total genetic deletion of Epac1 in mice accelerated the progression of nephrotoxic serum (NTS)-induced GN. Next, mice with podocyte-specific conditional deletion of Epac1 were generated and showed that NTS-induced GN was exacerbated in these mice. Gene expression analysis in glomeruli at the early and late phases of GN showed that deletion of Epac1 in podocytes was associated with major alterations in mitochondrial and metabolic processes and significant dysregulation of the glycolysis pathway. In vitro, Epac1 activation in a human podocyte cell line increased mitochondrial function to cope with the extra energy demand under conditions of stress. Furthermore, Epac1-induced glycolysis and lactate production improved podocyte viability. To verify the in vivo therapeutic potential of Epac1 activation, the Epac1 selective cAMP mimetic 8-pCPT was administered in wild type mice after induction of GN. 8-pCPT alleviated the progression of GN by improving kidney function with decreased structural injury with decreased crescent formation and kidney inflammation. Importantly, 8-pCPT had no beneficial effect in mice with Epac1 deletion in podocytes. Thus, our data suggest that Epac1 activation is an essential protective mechanism in GN by reprogramming podocyte metabolism. Hence, targeting Epac1 activation could represent a potential therapeutic approach.

Is resveratrol really effective in kidney disease?: A different perspective than ever before

Background Chronic kidney disease (CKD) is a global health problem and it is stated that the use of resveratrol supplement contributes to the protection of kidney health. In this study, it was aimed to evaluate the effect of resveratrol supplementation on kidney function, inflammation and histopathological findings in rats with experimental adenine-induced kidney damage. Methods Three different groups of 10 randomly selected rats were formed. The first group was the negative control group, the second group was the uremic control group (KDG), and the third group was the group in which uremia was created and resveratrol was applied (RG). Kidney damage was induced by administration of 200 mg/kg adenine. Resveratrol supplementation was administered at 20 mg/kg after kidney damage. Serum urea, creatinine, indoxyl sulfate (IS), p-cresol, glomerular filtration rate, C-reactive protein (CRP); interleukin (IL)-6 and tumor necrosis factor (TNF)-α gene expression levels and histopathological findings were evaluated. Results It was determined that resveratrol supplement applied after the formation of connective tissue in renal failure didn’t have an improvement effect on the urine amount, kidney function and inflammatory parameters and histopathological changes (p > 0.05). Just, the increase in the CRP value of KDG (p < 0.05) was not observed in RG. Conclusion The findings suggest that resveratrol administered after kidney damage with adenine has no effect on kidney disease.

#921 Interferon regulatory factor 4 (IRF4)-specific deletion on dendritic cells protects against kidney inflammation and injury in IRI-induced AKI/AKD

Abstract Background and Aims Ischemia-reperfusion injury (IRI) is a frequent clinical cause of acute kidney injury and disease (AKI/AKD) which can lead to acute tubular necrosis and irreversible kidney function loss. Mononuclear phagocytes, including dendritic cells (DCs), Monocytes, and macrophages, play important roles in various phases of injury and repair processes. Previous research has indicated that conventional dendritic cells (cDCs) are subdivided into cDC1s and cDC2s, and these two subsets could have opposing functions. We also demonstrated that cDC1s have a protective role as deficiency of cDC1s results in aggravated inflammation and injury in the IRI-induced AKI/AKD model in our previous study. Based on these researches, we aim to investigate the function of cDC2s in the IRI-induced AKI/AKD model. Method We used interferon regulatory factor 4 (IRF4)-deficient mice (IRF4fl/flClec9acre) to specifically delete IRF4 on DC lineage cells as our experimental group, and used wide-type mice as our control group. After unilateral IRI (UIRI) surgery, we measured the GFR and plasma creatinine of the mice on day 1 (D1) and day 5 (D5), then collected the injured kidney issue after sacrificing mice. We compared the differences between IRF4fl/flClec9acre mice and wild-type mice in terms of DC subpopulation changes, neutrophil accumulation, T cell differentiation, intensity of inflammatory responses, and tissue repair capabilities in damaged kidney tissue, by using techniques such as immunohistochemistry, immunofluorescence, flow cytometry, qRT-PCR, etc. Results ([KOMean-WTMean] ± SEM): IRF4fl/flClec9acre mice showed a lower percentage of cDC2s without affecting cDC1s in the kidney compared with wide-type mice (D1: −0.04467 ± 0.01356, P = 0.0301; D5: −1.108 ± 0.2248, P = 0.0004). During post-ischemic AKI/AKD, IRF4 deficiency in cDCs had several beneficial effects compared to wild-type mice, including reducing renal tubular cell injury (PAS score D1: −0.9375 ± 0.1523, P &amp;lt; 0.0001; PAS score D5: −1.119 ± 0.1445, P &amp;lt; 0.0001), decreasing loss of kidney function (GFR D1: 8.983 ± 4.091, P = 0.1041; GFR D5: 14.9 ± 5.01, P = 0.0172), and promoting kidney function recovery. This was associated with increased expression of anti-inflammatory cytokines (IL-4 D1: 4.486 ± 1.363, P = 0.0079; IL-4 D5: 3.403 ± 1.447, P = 0.0366; IL-10 D1: 2.103 ± 0.7342, P = 0.0299; IL-10 D5: 2.654 ± 0.8859, P = 0.0166), decreased expression of pro-inflammatory cytokines(TNF-α D1: −1.418 ± 0.5467, P = 0.0433; TNF-α D5: −2.434 ± 1.919, P = 0.0074; IL-23a D1: −1.320 ± 0.3432, P = 0.0061; IL-23a D5: −16.12 ± 3.587, P = 0.0004) and acute tubular cell death, reduced neutrophil chemoattractant expression (CXCL-2) (Fig. 6) and recruitment of neutrophils (−6.107 ± 1.664, P = 0.0214), and differentiation of Th2 (−0.1867 ± 0.03333, P = 0.005) and Th17 cells (−0.1767 ± 0.01333, P = 0.0002). Conclusion In conclusion, our data demonstrate a critical role of IRF4 in the kidney cDC2 subset and highlight that deficiency of cDC2s can protect against kidney inflammation, reduce kidney injury, and promote kidney recovery in the IRI-induced AKI/AKD model. This suggests that cDC2s have an immunoregulatory role in AKI/AKD and could serve as a potential therapeutic target for kidney inflammation.

#539 The active ingredient in the Nuphar lutea plant DTBN, ameliorates kidney damage and inflammation in a mouse model of chronic kidney disease (CKD)

Abstract Background and Aims Complications associated with Chronic Kidney Disease (CKD), such as disease progression and anemia, are closely linked to heightened inflammation mediated by the innate immune response. This inflammation can be mitigated through the use of anti-inflammatory agents. 6,6′-dihydroxythiobinupharidine (DTBN), an active compound derived from the aquatic plant Nuphar lutea, demonstrates notable anti-inflammatory properties, primarily by inhibiting NF-κB and LPS-induced cytokine activation. DTBN has shown efficacy in priming neutrophils, enhancing phagocytosis, regulating reactive oxygen species (ROS) production, and modulating NET formation. This study aimed to assess the impact of DTBN on CKD in mice. Method Male C57BL/6J mice, aged 8 weeks, were subjected to an adenine diet known to induce CKD through crystal deposition and tubulointerstitial inflammation. Both control and CKD-induced mice received intraperitoneal injections of DTBN (25 μg QOD) or saline and were euthanized after 8 weeks for evaluation. Results CKD mice treated with DTBN exhibited a significant decrease in serum urea and creatinine levels compared to untreated CKD mice (reduction by 1.4-fold and 1.3-fold, respectively). Histological analysis of kidney tissues revealed a notable reduction in F4/80 positive macrophage infiltration (3.4-fold decrease) and damaged renal areas (three-fold decrease), along with diminished kidney TGF-β levels in DTBN-treated CKD mice. Moreover, the p65 subunit of NF-κB showed a three-fold reduction in CKD mice treated with DTBN compared to untreated CKD mice. Indices of kidney inflammation (IL-1β, IL-6, and P-STAT3) were notably decreased in CKD mice treated with DTBN (reduction by 1.4-fold, 1.6-fold, and 2.9-fold, respectively) compared to untreated CKD mice. Notably, DTBN treatment in control mice did not induce apparent tissue damage; however, it led to reduced weight gain and mild hypoalbuminemia without proteinuria. Conclusion DTBN demonstrated significant improvements in renal function and inflammation indices in CKD mice. Hence, DTBN and substances similar to DTBN could be considered as supplementary treatments for CKD patients.

#2330 Fisetin supplement ameliorates aging related changes in the kidney

Abstract Background and Aims As the ageing population continues to grow worldwide, aging-related diseases are becoming an excessive burden on the global healthcare system. The kidney is one of the organs most affected by aging, which undergoes changes of decreased glomerular filtration rate (GFR), alterated renal blood flow, increased inflammation and fibrosis that increase the susceptibility to developing acute kidney injury (AKI) and chronic kidney disease (CKD). To date, the mechanisms underlying the changes of aged kidneys has not been fully elucidated and therapeutic strategies are still under exploration. Fisetin is a natural flavonol that has been shown to be beneficial to many age-related disorders, as well as increase lifespan in preclinical animal models. However, whether and how fisetin protects against kidney aging remains unclear. In the present study, we assessed the efficacy of fisetin as a senolytic to reduce cell senescence and SASP factors and improve renal function in old mice. Method 18 month-old C57BL/6 mice were randomly divided into the model group (n = 6), the fisetin low-dose group (100 mg/kg/d B.W., n = 6), fisetin high-dose group (100 mg/kg/d B.W., n = 6) and the rapamycin group (14 ppm, positive control, n = 6). The control group (n = 6) was composed of wild-type C57BL/6 mice of 4 month age. The fisetin and rapamycin were given in the diet for 4 months. Mice of model and treatment group were sacrificed at the age of 22 month and the blood and kidney samples were collected. The GFR of mice in each group was detected and the pathological morphology, lipid accumulation, collagen deposition of the kidneys were assessed. Additionally, the expressions of senescence markers including p53, p21,p16, and SASPs within the kidneys were analyzed. Results Fisetin treatment effectively restored the decline in GFR of old mice. Moreover, administration with fisetin significantly reduced age-related pathology including lipid accumulation and collagen fiber deposition in mice kidneys. The expression of aging markers of p53, p21,p16 and SASPs was remarkably upregulated in the kidneys of model mice, which was suppressed by fisetin treatment. Moreover, the kidney inflammation and oxidative stress as observed in aged kidneys was alleviated in mice of fisetin treatment group. Conclusion The natural product fisetin has senotherapeutic activity in mice kidneys. Intervention with fisetin is a promising therapy for clinical translation to target excess cell senescence to treat age-related kidney dysfunction.

#2307 Serum NGAL, MMP-9 and suPAR in the assessment of kidney impairment and cardiovascular risk in children and adolescents with type 1 diabetes or obesity

Abstract Background and Aims Type 1 diabetes mellitus (DM1) and obesity represent two chronic paediatric diseases with worryingly rising incidence, characterized by chronic inflammation, endothelial dysfunction and increased risk for kidney impairment and cardiovascular disease. The aim of this cross-sectional study was to explore the potential usefulness of serum Neutrophil Gelatinase-Associated Lipocalin (NGAL), Matrix Metalloproteinase-9 (MMP-9) and Soluble Urokinase Plasminogen Activator Receptor (suPAR) for predicting early kidney injury or increased cardiovascular risk in children and adolescents with DM1 or obesity. Method Serum samples were obtained from children and adolescents aged &amp;lt;18 years old with DM1 (n=35) or obesity (n=38) and normal renal function with no history of albuminuria, as well as from healthy controls (n=23). Serum NGAL, MMP-9 and suPAR concentrations were measured using commercially available sandwich ELISA kits (NGAL: (DY1757-05), MMP-9: (DMP900); suPAR: (DUP00); R&amp;D systems). All patients were evaluated for anthropometric indices (weight, height, BMI) while for different degrees of weight status we used the body mass index (BMI) z-score adjusted for age and sex. Estimated glomerular filtration rate (eGFR) was calculated according to the revised bedside Schwartz formula. Results Serum NGAL values were found significantly higher in patients with obesity but not in those with DM1. A positive correlation was found in patients with T1DM with diabetes duration (Spearman rho 0.364, p=0.044), and in all study participants with BMI z-score (Spearman rho 0.401, p=0.004). Furthermore, serum MMP-9 levels were significantly increased in patients with T1DM and in patients with obesity compared to controls. Mean serum suPAR levels were significantly higher in patients with obesity compared to patients with T1DM and controls, while children with T1DM had similar suPAR levels to controls (Table 1). Finally, serum suPAR levels showed a negative correlation with age (Spearman rho −0.359, p&amp;lt;0.001) and creatinine levels (Spearman rho −0.334, p=0.005), and a positive correlation with BMI z-score (Spearman rho 0.354, p=0.009). Conclusion Circulating NGAL, MMP-9 levels may prove useful as surrogate biomarkers to creatinine, GFR and albumin excretion rate for early detection of kidney injury, inflammation or endothelial dysfunction and cardiovascular complications in children and adolescents with T1DM or obesity. Children with obesity may have impaired inflammation status, kidney and endothelial function to a higher degree compared to children with T1DM, which may suggest that obesity may impose a greater health burden than T1DM, at least during childhood or the first years after T1DM diagnosis.

#753 Targeted anti-IL-1β bacteroides fragilis outer membrane vesicles alleviate inflammatory injury in diabetic nephropathy

Abstract Background and Aims It is accepted that diabetic nephropathy (DN) is not only a disease caused by impaired glucose metabolism, but also a chronic inflammatory disease. The interleukin-1β (IL-1β) plays an important role in inflammation-mediated renal injury in DN. IL-1β blocking therapy can prevent inflammatory cytokine-mediated kidney injury. However, the high cost and systemic side effects of IL-1β antibodies limit its application. Therefore, firstly this study aimed to construct kidney-targeting outer membrane vesicles (OMVs) of Bacteroides fragilis loaded with IL-1β single-chain variable fragment (scFv). These OMVs derived from human commensal non-toxigenic Bacteroides fragilis have been proven to play an immunosuppressive role in the intestine and distant organs. This targeted drug delivery platform built with this as a carrier is expected to relieve kidney inflammation in the development of DN. Methods We recombinantly expressed the scFv based on the Gevokizumab sequence in Escherichia coli, and loaded it into the OMVs derived from Bacteroides fragilis by multiple ultrasounds. The targeting peptide with the sequence (KKEEE)3{Lys(N3)} was connected to the membrane surface through a copper-free catalyzed click chemistry reaction. The package, which consisted of OMVs and the scFv targeting IL-1β in the kidney (OMV-KTP-scFv) was obtained. OMV-KTP-scFv treated in HK-2 cells and healthy mice respectively, and evaluated its in vitro and in vivo drug safety. The concentration of IL-1β scFv in blood and kidney tissues at different time points were measured using streptozotocin (STZ)-induced diabetic mice. DID-labeled OMVs was used for ex vivo infrared imaging of various organs to evaluate the delivery efficiency of the targeted carrier. In vitro, OMV-KTP-scFv was used to prevent inflammation in mouse primary renal tubular epithelial cells induced by high glucose, and in vivo to alleviate kidney injury in STZ-induced diabetic mice. Results We successfully prepared OMV-KTP-scFv and confirmed the co-localization of OMVs, KTP, and scFv using super-resolution microscopy. The prepared OMV-KTP-scFv had high stability, effectively extended the plasma half-life of scFv, and could deliver scFv accurately to the proximal renal tubules. Furthermore, OMV-KTP-scFv also had good safety in vitro and in vivo, and no obvious biotoxicity was found during long-term in vivo administration. In addition, our results show that OMV-KTP-scFv significantly inhibited the expression of inflammatory factors in renal tubular cells of DN, reduced the infiltration of renal interstitial inflammatory cells, and alleviated renal tubular injury. Conclusion Our findings demonstrated that OMVs of Bacteroides fragilis targeting the kidney can deliver the IL-1β scFv to the renal tubulointerstitium and reduce the renal interstitial injury in DN by antagonizing local inflammation.

#1524 SKLB023 alleviates kidney inflammation and apoptosis via inhibiting TLR4-mediated NF-κB p65 and MAPK signaling pathways in septic AKI mice

Abstract Background and Aims Sepsis is a severe and complex clinical syndrome resulting from the host's inflammatory response to infection. Acute kidney injury (AKI) is one of the major complications of sepsis with high morbidity and mortality, namely sepsis-associated acute kidney injury (S-AKI). Despite current advances, effective drugs for treatment of S-AKI are scarce. SKLB023 is a small molecule compound designed based on 5-benzylidene-thiazolidine-2,4-dione, which has a potent anti-inflammatory effect with favorable efficacy in rheumatoid arthritis. This study aims to evaluate the efficacy of SKLB023 in treating S-AKI and to explore the underlying mechanisms. Method S-AKI was induced by cecal ligation puncture (CLP) and intraperitoneal injection of LPS (10 mg/kg) in male C57BL/6 mice. SKLB023 (25 mg/kg, 50 mg/kg) was administrated by gavage three days in advance and 30 minutes earlier on the day of modeling. Mice death per group was recorded for 100 hours after CLP to evaluate the effect of SKLB023 on the survival rate of S-AKI mice. Other mice were sacrificed 16 hours after model establishment, blood and kidney specimens were collected. Renal function was measured by the detection of serum creatinine (SCr) and blood urea nitrogen (BUN). Kidney pathological injury was evaluated by the expression of kidney injury markers and the assessment of PAS/HE stainings. In vitro experiments were performed with LPS stimulation of TCMK-1 cells and SKLB023 intervention, and the doses were determined by CCK-8 assay. Possible molecular mechanisms involved in SKLB023 against S-AKI were screened by bioinformatics analysis and further validated in vivo and vitro. RT-PCR, western blot, immunofluorescence, and immunohistochemistry were applied to detect renal inflammation and apoptosis. To determine the role of TLR4, TLR4 siRNA and TLR4-KO mice were applied in S-AKI model, and TLR4 expression and the activities of NF-κB p65 and MAPK signaling pathway were assessed. One-way ANOVA was performed for comparison between groups, and logrank analysis was used for comparison of survival curve. P &amp;lt; 0.05 was considered as statistically significant. Results The S-AKI model was successfully established by CLP and LPS injection with obvious renal dysfunction and kidney pathological damage. The mice administrated with SKLB023 had a higher survival rate, lower levels of Scr and BUN, and improved kidney pathological injury than the mice in the CLP group. Transcriptomic analysis identified TLR4-mediated downstream signaling pathways as the potential mechanism of SKLB023 and further experiments in vivo and in vitro proved that SKLB023 regulated the expression of TLR4 and the activities of NF-κB p65 and MAPK signaling pathway in S-AKI mice and LPS-stimulated TCMK-1 cells. Moreover, TLR4 inhibited the expression of inflammatory cytokines including TNF-α, IL-1β, IL-6, iNOS, COX-2, HMGB-1 and alleviated kidney apoptosis in S-AKI mice and LPS-treated TCMK-1 cells. Additionally, knockout of TLR4 remarkably improved inflammation, apotosis, and kidney injury in LPS-treated mice and TCMK-1 cells. Conclusion SKLB023 confers renoprotective effects in S-AKI by modulating inflammation and apoptosis. TLR4 is a key target in S-AKI, and SKLB023 inhibits inflammation and apoptosis by inhibiting the activities of TLR4 mediated NF-κB p65 and MAPK pathways. SKLB023 may be proposed as one of the potential preventive and therapeutic agents for S-AKI.

Inhibition of mTORC2 promotes natriuresis in Dahl salt-sensitive rats via the decrease of NCC and ENaC activity.

We have previously observed that prolonged administration of rapamycin, an inhibitor targeting the mammalian target of rapamycin complex (mTORC)1, partially reduced hypertension and alleviated kidney inflammation in Dahl salt-sensitive (SS) rats. In contrast, treatment with PP242, an inhibitor affecting both mTORC1/mTORC2, not only completely prevented hypertension but also provided substantial protection against kidney injury. Notably, PP242 exhibited potent natriuretic effects that were not evident with rapamycin. The primary objective of this study was to pinpoint the specific tubular sites responsible for the natriuretic effect of PP242 in SS rats subjected to either 0.4% NaCl (normal salt) or 4.0% NaCl (high salt) diet. Acute effects of PP242 on natriuretic, diuretic, and kaliuretic responses were determined in unanesthetized SS rats utilizing benzamil, furosemide, or hydrochlorothiazide [inhibitors of epithelial Na+ channel (ENaC), Na-K-2Cl cotransporter (NKCC2), or Na-Cl cotransporter (NCC), respectively] either administered alone or in combination. The findings indicate that the natriuretic effects of PP242 in SS rats stem predominantly from the inhibition of NCC and a reduction of ENaC open probability. Molecular analysis revealed that mTORC2 regulates NCC activity through protein phosphorylation and ENaC activity through proteolytic cleavage in vivo. Evidence also indicated that PP242 also prevents the loss of K+ associated with the inhibition of NCC. These findings suggest that PP242 may represent an improved therapeutic approach for antihypertensive intervention, potentially controlling blood pressure and mitigating kidney injury in salt-sensitive human subjects.NEW & NOTEWORTHY This study explored mechanisms underlying the natriuretic effects of mammalian target of rapamycin protein complex 2 inhibition using PP242 and revealed both epithelial Na+ channel and Na-Cl cotransporter in the distal tubular segments were potentially inhibited. These observations, with prior lab evidence, indicate that PP242 prevents hypertension via its potent inhibitory effects on these specific sodium transporters and by reducing renal immune responses. This dual action, coupled with potassium sparing effects, suggests an improved approach for managing hypertension and associated kidney damage.

The glycolytic enzyme PFKFB3 drives kidney fibrosis through promoting histone lactylation-mediated NF-κB family activation

Persistently elevated glycolysis in kidney has been demonstrated to promote chronic kidney disease (CKD). However, the underlying mechanism remains largely unclear. Here, we observed that 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3), a key glycolytic enzyme, was remarkably induced in kidney proximal tubular cells (PTCs) following ischemia-reperfusion injury (IRI) in mice, as well as in multiple etiologies of patients with CKD. PFKFB3 expression was positively correlated with the severity of kidney fibrosis. Moreover, patients with CKD and mice exhibited increased urinary lactate/creatine levels and kidney lactate, respectively. PTCs-specific deletion of PFKFB3 significantly reduced kidney lactate levels, mitigated inflammation and fibrosis, and preserved kidney function in the IRI mouse model. Similar protective effects were observed in mice with heterozygous deficiency of PFKFB3 or those treated with a PFKFB3 inhibitor. Mechanistically, lactate derived from PFKFB3-mediated tubular glycolytic reprogramming markedly enhanced histone lactylation, particularly H4K12la, which was enriched at the promoter of NF- κB signaling genes like Ikbkb, Rela, and Relb, activating their transcription and facilitating the inflammatory response. Further, PTCs-specific deletion of PFKFB3 inhibited the activation of IKKβ, I κ B α, and p65 in the IRI kidneys. Moreover, increased H4K12la levels were positively correlated with kidney inflammation and fibrosis in patients with CKD. These findings suggest that tubular PFKFB3 may play a dual role in enhancing NF- κB signaling by promoting both H4K12la-mediated gene transcription and its activation. Thus, targeting the PFKFB3-mediated NF- κB signaling pathway in kidney tubular cells could be a novel strategy for CKD therapy.

Study on the anti–inflammatory effect of 3–(4–hydroxyphenyl) propionic acid in an in vitro LPS–stimulated acute kidney inflammation model

Acute kidney injury (AKI) is a syndrome defined by a rapid decrease in glomerular filtration that can be caused by sepsis, ischemia/reperfusion injury (IRI), or nephrotoxic drugs. Human microbiota makes significant contributions to human health by enzymatic transformation of such active substances and the release of molecules such as 3–4 hydroxyphenyl propionic acid (4–HPPA). Biological effects of 4–HPPA such as anti–inflammatory and antioxidant have been reported in many studies. The aim of the research is to reveal the anti–inflammatory activity of 4–HPPA, one of the microbiota products of flavonoids (especially naringin) found in many fruits, in an in vitro LPS (lipopolysaccharide) stimulated kidney inflammation model. HEK 293 kidney cells of human origin were used as material in the research. The trial consisted of 4 groups: control group, LPS group, 4–HPPA group and 4–HPPA+LPS group. LPS and 4–HPPA were applied to the cells at different concentrations for 24 hours. Effective concentrations of LPS and 4–HPPA were investigated by MTT viability test. Finally, IL–1β, TNF–α and NFkβ gene expression analyzes responsible for inflammatory responses were investigated by qRT–PCR method. According to the findings, after 24 hours of incubation, LPS at 2.5 ng·mL-1 and 4–HPPA at 6.25 μg·mL-1 were determined to be effective concentrations for the experiment. Again, it was observed that 4–HPPA downregulated LPS–induced IL–1β, TNF–α and NFkβ gene expressions by 7, 42 and 40%, respectively. According to the data obtained from the research, it was revealed that 4–HPPA had effective anti–inflammatory properties in the in vitro LPS–stimulated kidney inflammation model. However, it was concluded that in vivo and more advanced molecular methods are needed to fully elucidate the issue.

Insights into Kidney Dysplasia in Duplex Kidneys: From Radiologic Diagnosis to Histopathologic Understanding.

Duplex kidney is a urinary tract anomaly commonly associated with a wide range of primary and secondary parenchymal structural abnormalities. We present a unique comparison of US and MRI findings with histopathology following partial resection of duplex kidneys due to nephropathy. We examined a group of 21 children with duplex kidneys who were qualified for heminephrectomy (24 kidney units (KU)). All patients underwent US and MRI prior to the surgery. The imaging results were compared with histopathologic findings. In 21/24 KU, dysplastic changes were found on histopathology, including all with obstructive nephropathy and 7/10 specimens with refluxing uropathy. The loss of corticomedullary differentiation on US and increased signal on T2-weighted images (T2WI) on MRI were the imaging findings that best correlated with fibrosis. In children with megaureter, there were no statistical differences in histopathological findings between primary megaureter, megaureter with ureterocele, and megaureter with ectopia (p > 0.05). The extent of dysplasia of the affected pole correlated negatively with residual function in MRI. Kidney dysplasia and inflammation in the kidney with obstructive nephropathy are the most important histopathologic findings of this study. US is a valuable screening tool, and MRI enables morphologic and functional assessments of the nephropathy in duplex kidneys.

An anti-inflammatory active ingredients in Poriae cutis: Screening based on network pharmacology.

Hyperuricemia (HUA) is a disorder of uric acid metabolism, which can lead to the formation of gouty arthritis, kidney inflammation and other damages. Previous studies have found that the alcohol extract of Poria cutis can reduce the level of uric acid and protect against kidney injury. Based on network pharmacology, the core targets and main active components of P. cutis intervention in HUA were determined. Most of the potential active ingredients are triterpenoid acids such as tumulosic acid (TA) and eburicoic acid (EA), and the potential targets are TNF and IL-6, which are associated with inflammation. In vitro experiments have shown that TA can significantly inhibit the release of NO, TNF-α and IL-6 in inflammatory RAW264.7 cell culture medium and the expression of TNF-α and IL-6 in RAW264.7 cells. This study suggests that TA based on network pharmacological screening has obvious anti-inflammatory effect on inflammatory RAW264.7 cells and is a promising anti-inflammatory compound.

Up-regulation of long non-coding RNA H19 ameliorates renal tubulointerstitial fibrosis by reducing lipid deposition and inflammatory response through regulation of the microRNA-130a-3p/long-chain acyl-CoA synthetase 1 axis

Long non-coding RNA (lncRNA) H19 is an extensively studied lncRNA that is related to numerous pathological changes. Our previous findings have documented that serum lncRNA H19 levels are decreased in patients with chronic kidney disorder and lncRNA H19 reduction is closely correlated with renal tubulointerstitial fibrosis, an essential step in developing end-stage kidney disease. Nonetheless, the precise function and mechanism of lncRNA H19 in renal tubulointerstitial fibrosis are not fully comprehended. The present work utilized a mouse model of unilateral ureteral obstruction (UUO) and transforming growth factor-β1 (TGF-β1)-stimulated HK-2 cells to investigate the possible role and mechanism of lncRNA H19 in renal tubulointerstitial fibrosis were investigated. Levels of lncRNA H19 decreased in kidneys of mice with UUO and HK-2 cells stimulated with TGF-β1. Up-regulation of lncRNA H19 in mouse kidneys remarkably relieved kidney injury, fibrosis and inflammation triggered by UUO. Moreover, the increase of lncRNA H19 in HK-2 cells reduced epithelial-to-mesenchymal transition (EMT) induced by TGF-β1. Notably, up-regulation of lncRNA H19 reduced lipid accumulation and triacylglycerol content in kidneys of mice with UUO and TGF-β1-stimulated HK-2 cells, accompanied by the up-regulation of long-chain acyl-CoA synthetase 1 (ACSL1). lncRNA H19 was identified as a sponge of microRNA-130a-3p, through which lncRNA H19 modulates the expression of ACSL1. The overexpression of microRNA-130a-3p reversed the lncRNA H19-induced increases in the expression of ACSL1. The suppressive effects of lncRNA H19 overexpression on the EMT, inflammation and lipid accumulation in HK-2 cells were diminished by ACSL1 silencing or microRNA-130a-3p overexpression. Overall, the findings showed that lncRNA H19 ameliorated renal tubulointerstitial fibrosis by reducing lipid deposition via modulation of the microRNA-130a-3p/ACSL1 axis.

Increased Erythrocyte Sedimentation Rate in Dogs: Frequency in Routine Clinical Practice and Association with Hematological Changes.

(1) Background: the erythrocyte sedimentation rate (ESR) has been reported to increase in some infectious or inflammatory diseases in dogs, but no information on the frequency of increases in a routine clinical setting exists. The aim of this study was to assess the frequency of an increased ESR in dogs and to investigate its possible association with hematologic changes; (2) Methods: A total of 295 EDTA blood samples were randomly selected from the routine caseload of the Veterinary Teaching Hospital. Samples were grouped in controls and in pathologic groups based on the clinical presentation. A routine hemogram was performed, then the ESR was measured using the instrument MINI-PET; (3) Results: compared with controls, the ESR was significantly higher in all the pathologic groups, except for the hematological disorders group. The highest ESR was found in samples from dogs with chronic kidney disease or inflammation, followed by those from dogs with mild chronic disorders, severe/acute diseases, tumors and urinary disorders. The ESR negatively correlated with hematocrit and positively with neutrophil counts. (4) Conclusions: The ESR increases more frequently in dogs with clinically evident inflammation or CKD, but also in several other conditions, likely as a consequence of anemia and acute phase response.