Adriamycin-induced Nephropathy Research Articles

Counteracting TGM2 by a Fibroin peptide ameliorated Adriamycin-induced nephropathy via regulation of lipid metabolism through PANX1-PPAR α/PANK1 pathway

Peptide drug discovery for the treatment of chronic kidney disease (CKD) has attracted much attention in recent years due to the urge to find novel drugs and mechanisms to delay the progression of the disease. In this study, we identified a novel short peptide (named YR-7, primary sequence ‘YEVEDYR’) from the natural Fibroin protein, and demonstrated that it significantly alleviated pathological renal changes in ADR-induced nephropathy. PANX1 was identified as the most notably upregulated component by RNA-sequencing. Further analysis showed that YR-7 alleviated the accumulation of lipid droplets via regulation of the lipid metabolism-related proteins PPAR α and PANK1. Using chemical proteomics, fluorescence polarization, microscale thermophoresis, surface plasmon resonance, and molecular docking, YR-7 was proven to directly bind to β-barrel domains of TGM2 protein to inhibit lipid accumulation. TGM2 knockdown in vivo increased the protein levels of PPAR α and PANK1 while decreased the levels of fibrotic-related proteins to alleviate nephropathy. In vitro, overexpression TGM2 reversed the protective effects of YR-7. Co-immunoprecipitation indicated that TGM2 interacted with PANX1 to promote lipid deposition, and pharmacological inhibition or knockdown of PANX1 decreased the levels of PPAR α and PANK1 induced by ADR. Taken together, our findings revealed that TGM2-PANX1 interaction in promoting lipid deposition may be a new signaling in promoting ADR-induced nephropathy. And a novel natural peptide could ameliorate renal fibrosis through TGM2-PANX1-PPAR α/PANK1 pathway, which highlight the potential of it in the treatment of CKD.

Development and Characterization of a Novel FVB-PrkdcR2140C Mouse Model for Adriamycin-Induced Nephropathy.

The Adriamycin (ADR) nephropathy model, which induces podocyte injury, is limited to certain mouse strains due to genetic susceptibilities, such as the PrkdcR2140C polymorphism. The FVB/N strain without the R2140C mutation resists ADR nephropathy. Meanwhile, a detailed analysis of the progression of ADR nephropathy in the FVB/N strain has yet to be conducted. Our research aimed to create a novel mouse model, the FVB-PrkdcR2140C, by introducing PrkdcR2140C into the FVB/NJcl (FVB) strain. Our study showed that FVB-PrkdcR2140C mice developed severe renal damage when exposed to ADR, as evidenced by significant albuminuria and tubular injury, exceeding the levels observed in C57BL/6J (B6)-PrkdcR2140C. This indicates that the FVB/N genetic background, in combination with the R2140C mutation, strongly predisposes mice to ADR nephropathy, highlighting the influence of genetic background on disease susceptibility. Using RNA sequencing and subsequent analysis, we identified several genes whose expression is altered in response to ADR nephropathy. In particular, Mmp7, Mmp10, and Mmp12 were highlighted for their differential expression between strains and their potential role in influencing the severity of kidney damage. Further genetic analysis should lead to identifying ADR nephropathy modifier gene(s), aiding in early diagnosis and providing novel approaches to kidney disease treatment and prevention.

Effect of intermittent fasting on adriamycin-induced nephropathy: Possible underlying mechanisms

PurposeIntermittent fasting (IF) has been shown to induce a well-organized adaptive defense against stress inside the cells, which increases the production of anti-oxidant defenses, repair of DNA, biogenesis of mitochondria, and genes that combat inflammation. So, the goal of the current investigation was to identify the effects of IF on rats with adriamycin (ADR)-induced nephropathy and any potential underlying mechanisms. MethodsFour groups of 40 mature Sprague-Dawley male rats were allocated as follow; control, fasting, ADR, and ADR plus fasting. After 8 weeks of ADR administration urine, blood samples and kidneys were taken for assessment of serum creatinine (Cr), BUN, urinary proteins, indicators of oxidative damage (malondialdehyde (MDA), reduced glutathione (GSH) and Catalase (CAT) levels), histopathological examinations, immunohistochemical examinations for caspase-3, Sirt1, aquaporin2 (AQP2) and real time PCR for antioxidant genes; Nrf2, HO-1 in kidney tissues. ResultsIF significantly improved serum creatinine, BUN and urinary protein excretion, oxidative stress (low MDA with high CAT and GSH), in addition to morphological damage to the renal tubules and glomeruli as well as caspase-3 production during apoptosis. Moreover, IF stimulates significantly the expression of Sirt1 and Nrf2/HO-1 and AQP2. ConclusionAQP2, Sirt1, Nrf2/HO-1 signaling may be upregulated and activated by IF, which alleviates ADR nephropathy. Enhancing endogenous antioxidants, reducing apoptosis and tubulointerstitial damage, and maintaining the glomerular membrane's integrity are other goals.

Effects of N-acetyl-L-cysteine against apical periodontitis in rats with adriamycin-induced cardiomyopathy and nephropathy.

This study aimed to investigate the potential protective effects of N-acetyl-L-cysteine (NAC) against apical periodontitis (AP) in rats with adriamycin (ADR)-induced kidney and heart diseases. Fourty-eight Wistar albino rats were divided into six groups: (1) Control group, (2) ADR group (1 mg/kg/day ip for 10 days), (3) AP Group (1st mandibular molar tooth), (4) AP + ADR Group, (5) AP + NAC group (150 mg/kg/day ip), and (6) AP + ADR + NAC group. After 3 weeks, the rats were decapitated and blood and tissue samples (heart, kidney, and jaw) were collected. Tissue samples were evaluated by biochemical (inflammatory cytokines and hemodynamic parameters) and radiological analyses. One-way anova with Tukey post hoc tests was used to compare data, considering p < .05 as statistically significant. The serum levels of TNF-α, IL-1β, BUN, Creatinine, CK, and LDH were elevated in the test groups compared with the control group, and treatment with NAC reduced these levels (p < .05). Heart and kidney tissue analysis showed a higher heart-to-body weight ratio (HW/BW) and kidney-to-body weight ratio (KW/BW) in the test groups compared with the control group (p < .05). No significant differences in HW/BW and KW/BW were found between the control and AP + NAC groups. Volumetric apical bone resorption analysis showed an increase in periapical radiolucencies in AP-induced groups indicating apical periodontitis. NAC treatment reduced the total area and volume of resorption cavities (p < .05). The results suggest that NAC's antioxidant and anti-inflammatory effects can reduce adriamycin-mediated heart and kidney damage and may have a positive effect on apical periodontitis in individuals with nephropathy and cardiomyopathy.

Ameliorative effects of Modified Huangqi Chifeng decoction on podocyte injury via autophagy mediated by PI3K/AKT/mTOR and AMPK/mTOR pathways

Ethnopharmacological relevanceProteinuria is recognized as a risk factor for the exacerbation of chronic kidney disease. Modified Huangqi Chifeng decoction (MHCD) has distinct advantages in reducing proteinuria. Our previous experimental results have shown that MHCD can inhibit excessive autophagy. However, the specific mechanism by which MHCD regulates autophagy needs to be further explored. Aim of the studyIn this study, in vivo and in vitro experiments were conducted to further clarify the protective mechanism of MHCD on the kidney and podocytes by regulating autophagy based on phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) and adenosine monophosphate-activated protein kinase (AMPK)/mTOR signaling pathways. Materials and methodsBy a single injection via the tail vein, Sprague–Dawley rats received Adriamycin (5 mg/kg) to establish a model of proteinuria nephropathy. They were divided into control, model, MHCD, 3-methyladenine (3 MA), 3 MA + MHCD, and telmisartan groups and were administered continuously for 6 weeks. The MHCD-containing serum was prepared, and a model of podocyte injury induced by Adriamycin (0.2 μg/mL) was established. ResultsMHCD reduced the 24-h urine protein levels and relieved pathological kidney damage. During autophagy in the kidneys of rats with Adriamycin-induced nephropathy, the PI3K/AKT/mTOR signaling pathway is inhibited, while the AMPK/mTOR signaling pathway is activated. MHCD antagonized these effects, thereby inhibiting excessive autophagy. MHCD alleviated Adriamycin-induced podocyte autophagy, as demonstrated using Pik3r1 siRNA and an overexpression plasmid for Prkaa1/Prkaa2. Furthermore, MHCD could activate the PI3K/AKT/mTOR signaling pathway while suppressing the AMPK/mTOR signaling pathway. ConclusionsThis study demonstrated that MHCD can activate the interaction between the PI3K/AKT/mTOR and the AMPK/mTOR signaling pathways to maintain autophagy balance, inhibit excessive autophagy, and play a role in protecting the kidneys and podocytes.

The Therapeutic Mechanisms of Shenyan Oral Liquid I Against Chronic Kidney Disease Based on Network Pharmacology and Experimental Validation

Background: Chronic Kidney Disease (CKD) leads to structural and functional abnormalities of the kidneys and seriously jeopardizes human health. Shenyan Oral Liquid (SOLI), a Chinese medicinal preparation, has been reported to protect podocytes in patients with chronic kidney disease (CKD). Objective: The objective of this study is to investigate the mechanism of action of the Chinese medicinal preparation Senyan Oral Liquid (SOLI) in the treatment of CKD by protecting podocytes through network pharmacology technology and experimental validation. Methods: Compounds of SOLI and targets of CKD disease were collected and screened. The SOLI network of bioactive compounds targeting CKD and the protein-protein interaction (PPI) network were constructed using Cytoscape software and the STRING online database. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed using the R software Cluster Profiler package. Molecular docking was performed using Autodock software to verify the binding ability of bioactive compounds and target genes. Subsequently, the potential mechanism of SOLI on CKD predicted by network pharmacological analysis was experimentally studied and verified in an adriamycin-induced nephropathy rat model. Results: A total of 81 targets of SOLI components acting on CKD were identified. The results of the PPI analysis clarified that five key target genes (TNF, AKT1, IL6, VEGFA, and TP53) play a critical role in the treatment of CKD by SOLI. The GO analysis and KEGG enrichment analysis indicated that SOLI acts through multiple pathways, including the PI3K/AKT signaling pathway against CKD. Molecular docking showed that the main compounds of SOLI and five key genes had strong binding affinity. In a rat model of adriamycin-induced nephropathy, SOLI significantly ameliorated disease symptoms and improved renal histopathology. Mechanistic studies showed that SOLI upregulated the expression level of Nephrin, inhibited the PI3K/AKT pathway in renal tissues, and ultimately suppressed the activation of autophagy-related proteins in CKD Conclusion: SOLI exerted a renoprotective effect by regulating the Nephrin-PI3K/AKT autophagy signaling pathway, and these findings provide new ideas for the development of SOLI-based therapeutic approaches for CKD.

Podocyte-Specific Deletion of MCP-1 Fails to Protect Against Angiotensin II- or Adriamycin-Induced Nephropathy

Podocyte-Specific Deletion of MCP-1 Fails to Protect Against Angiotensin II- or Adriamycin-Induced Nephropathy

CDDO-Me ameliorates podocyte injury through anti-oxidative stress and regulation of actin cytoskeleton in adriamycin nephropathy

Podocyte injury is the common initiating event in focal segmental glomerulosclerosis (FSGS). Oxidative stress and inflammation mediate podocyte injury in FSGS. NRF2 pathway regulates the constitutive and inducible transcription of various genes that encode antioxidant proteins and anti-inflammatory proteins and have pivotal roles in the defense against cellular oxidative stress. In this study, we used adriamycin-induced nephropathy (ADR) in mice as a model of FSGS to confirm that CDDO-Me treatment ameliorated adriamycin-induced kidney damage by improving renal function and kidney histology. CDDO-Me inhibited the level of oxidative stress, inflammation, and apoptosis in adriamycin-induced podocyte injury by activating NRF2 pathway in vivo and in vitro. Furthermore, CDDO-Me stabled the cytoskeleton by regulating NRF2/srGAP2a pathway. Together, these findings show that by activating NRF2 pathway, CDDO-Me could be a therapeutic strategy to prevent the adverse effects of adriamycin-induced podocyte injury.

The E3 ligase Trim63 promotes podocyte injury and proteinuria by targeting PPARα to inhibit fatty acid oxidation

Podocyte injury is a hallmark of glomerular disease and one of the leading causes of chronic kidney disease (CKD). Peroxisome proliferator-activated receptor α (PPARα) plays a key role in podocyte fatty acid oxidation (FAO). However, the underlying regulatory mechanisms remain unresolved. Trim63 is an E3 ubiquitin ligase that has been shown to inhibit PPARα activity; however, its role in fatty acid metabolism in the kidney has not been elucidated to date. In this study, we investigated the effects of overexpression and knockdown of Trim63 in Adriamycin (ADR)-induced nephropathy and diabetic nephropathy models and a podocyte cell line. In both rodents and human patients with proteinuric CKD, Trim63 was upregulated, particularly in the podocytes of injured glomeruli. In the ADR-induced nephropathy model, ectopic Trim63 application aggravated FAO deficiency and mitochondrial dysfunction and triggered intense lipid deposition, podocyte injury, and proteinuria. Notably, Trim63 inhibition alleviated FAO deficiency and mitochondrial dysfunction, and markedly restored podocyte injury and renal fibrosis in ADR-induced and diabetic nephropathy (DN) models. Additionally, Trim63 was observed to mediate PPARα ubiquitination and degradation, leading to podocyte injury. We demonstrate the pathological role of Trim63, which was previously unrecognized in kidney tissue, in FAO deficiency and podocyte injury. Targeting Trim63 may represent a viable therapeutic strategy for podocyte injury and proteinuria.

Asparagine endopeptidase protects podocytes in adriamycin-induced nephropathy by regulating actin dynamics through cleaving transgelin

Focal segmental glomerulosclerosis (FSGS) is the most common glomerular disorder causing end-stage renal diseases worldwide. Central to the pathogenesis of FSGS is podocyte dysfunction, which is induced by diverse insults. However, the mechanism governing podocyte injury and repair remains largely unexplored. Asparagine endopeptidase (AEP), a lysosomal protease, regulates substrates by residue-specific cleavage or degradation. We identified the increased AEP expression in the primary proteinuria model which was induced by adriamycin (ADR) to mimic human FSGS. Invivo, global AEP knockout mice manifested increased injury-susceptibility of podocytes in ADR-induced nephropathy (ADRN). Podocyte-specific AEP knockout mice exhibited much more severe glomerular lesions and podocyte injury after ADR injection. In contrast, podocyte-specific augmentation of AEP in mice protected against ADRN. Invitro, knockdown and overexpression of AEP in human podocytes revealed the cytoprotection of AEP as a cytoskeleton regulator. Furthermore, transgelin, an actin-binding protein regulating actin dynamics, was cleaved by AEP, and, as a result, removed its actin-binding regulatory domain. The truncated transgelin regulated podocyte actin dynamics and repressed podocyte hypermotility, compared to the native full-length transgelin. Together, our data reveal a link between lysosomal protease AEP and podocyte cytoskeletal homeostasis, which suggests a potential therapeutic role for AEP in proteinuria disease.

#5466 CSF-1R SYSTEM ACTIVATES PARIETAL EPITHELIAL CELLS LEADING TO FOCAL SEGMENTAL GLOMERULOSCLEROSIS (FSGS)

Abstract Background and Aims Focal segmental glomerulosclerosis (FSGS) is the most common glomerular cause leading to end-stage kidney disease. Actual treatment of primary FSGS by immunosuppressive agents presents inconsistent results. Thus, new innovative strategies different from those used to date by taking into consideration podocyte renewal and maintenance or even strategies complementary to immunosuppression are needed. In FSGS, parietal epithelial cells (PECs) switch to an activated phenotype (aPECs) in response to podocyte damage promoting glomerulosclerosis. Colony-stimulating factor (CSF-1) is a hematopoietic growth factor that acts via its specific receptor, the tyrosine kinase receptor CSF-1R. CSF-1 has been detected in sera and renal biopsies from patients with different renal complications, including FSGS, attributing their role and presence to macrophage but not to glomerular cells. The potential cellular and molecular mechanisms involved are also unknown. In this work, we evaluated the implication of CSF-1/CSF-1R axis in the pathogenesis of FSGS and its potential as new pharmacological target point by using specific CSF-1R inhibitors. Specifically, we focused on the modulation of PECS activation by de novo production of CD44 and the preservation of podocyte loss. Method We evaluated the role of the CSF-1/CSF-1R axis as a driver of glomerular damage in FSGS in adriamycin-induced nephropathy (ADR) in mice, the main experimental model to study human FSGS. To this end, we treated or not ADR-animals with CSF-1R specific inhibitors, GW2580 or Ki20227 (n = 5-7 group). We determined the expression and localization of CSF-1R in the glomerulus in tissue by triple immunofluorescence (WT-1, SSeCks and CSF-1R) and their relevance in glomerulosclerosis (PAS and pro-fibrotic genes), the determination of de novo CD44 formation and its correlation with ERK1/2 pathway by immunohistochemistry (IH). We detected podocyte in the glomerulus by WT-1 IH and the localization of aPECS in the glomerular tuff by Claudin-1 and SSeCkS markers. Finally, we used isolated human kidney progenitor cells with and without CSF-1 treatment (n = 6/group) to identify potential key interactors of CSF-1 by RNAseq. We validated genes of interest in the FSGS experimental model. Results We observed a constitutively expression of CSF-1R in the glomerulus of control mice that significantly increased in ADR-treated mice, specifically in podocytes (WT1) and PECs (SSeCks), confirmed with mRNA expression. ADR-treated mice showed important events of sclerotic glomerulus and pro-fibrotic genes as collagen that was significantly reversed by the treatment with CSF-1R inhibitors (p&amp;lt;0.001). Results reflected a CSF-1R inhibitor-dependent renal function recovery with the use of the inhibitors with a reduction of proteinuria and an increase of glomerular filtration rate (p&amp;lt;0.001). We found a positive CD44 staining both in Bowman's capsule and inner the tuff of ADR-treated mice, accompanied by an increase of ERK1/2 activation. CSF-1R inhibitors significantly reduced the percentage of glomeruli with de novo CD44 production. Remarkably, podocyte depletion was also preserved with very similar levels to non-treated animals (p&amp;lt;0.001). For RNAseq results, 227 differentially expressed genes (considering a criterion of a probability of differential expression &amp;gt;0.9 and a |M| &amp;gt; 1) were subjected to enrichment analysis. The top significant gene ontology terms were mainly involved with interferon-induced genes. Genes involved in this pathway were validated in the FSGS model, showing an increase in mice treated with ADR compared to controls and alleviated with CSF-1R inhibitors (p&amp;lt;0.001). Conclusion In this study we propose a novel therapeutic strategy to FSGS-associated pathology based on the inhibition of CSF1-R activity having an impact on reducing aPECs, glomerulosclerosis, proteinuria, improving renal function and preserving the podocyte-progenitor phenotype, thus, in podocyte preservation against damage.

Epimedium sagittatum Maxim ameliorates adriamycin-induced nephropathy by restraining inflammation and apoptosis via the PI3K/AKT signaling pathway.

Modern pharmacological studies show that Epimedium sagittatum Maxim (EPI) has antioxidant, antiapoptotic, anti-inflammatory effects. However, the effects of EPI on adriamycin-induced nephropathy are unclear. The main purpose of this study is to investigate the effects of EPI on adriamycin-induced nephropathy in rats. The chemical composition of EPI was detected by high performance liquid chromatography. Network pharmacology was used to collect the effects of EPI on adriamycin nephropathy; renal histological changes, podocyte injury, inflammatory factors, oxidative stress levels, apoptosis levels, and the PI3K/AKT signaling pathway were examined. Moreover, analyze the effects of icariin (the representative component of EPI) on adriamycin-induced apoptosis and PI3K/AKT signaling pathway of NRK-52e cells. Network pharmacological results suggested that EPI may ameliorate adriamycin-induced nephropathy by inhibiting inflammatory response and regulating the PI3K/AKT signaling pathway. The experimental results showed that EPI could improve pathological injury, renal function, podocyte injury, and inhibit inflammation, oxidative stress, apoptosis in adriamycin-induced nephropathy rats through the PI3K/AKT signaling pathway. Furthermore, icariin inhibited adriamycin-induced mitochondrial apoptosis in NRK-52e cells. This study suggested that EPI ameliorates adriamycin-induced nephropathy by reducing inflammation and apoptosis through the PI3K/AKT signaling pathway, icariin may be the pharmacodynamic substance basis for this effect.

Yue-bi-tang attenuates adriamycin-induced nephropathy edema through decreasing renal microvascular permeability via inhibition of the Cav-1/ eNOS pathway.

Edema is one of the most typical symptoms of nephrotic syndrome. Increased vascular permeability makes a significant contribution to the progression of edema. Yue-bi-tang (YBT) is a traditional formula with excellent clinical efficacy in the treatment of edema. This study investigated the effect of YBT on renal microvascular hyperpermeability-induced edema in nephrotic syndrome and its mechanism. In our study, the content of target chemical components of YBT was identified using UHPLC-Q-Orbitrap HRMS analysis. A nephrotic syndrome model was replicated based on male Sprague-Dawley rats with Adriamycin (6.5mg/kg) by tail vein injection. The rats were randomly divided into control, model, prednisone, and YBT (22.2g/kg, 11.1g/kg, and 6.6g/kg) groups. After 14d of treatment, the severity of renal microvascular permeability, edema, the degree of renal injury, and changes in the Cav-1/eNOS pathway were assessed. We found that YBT could regulate renal microvascular permeability, alleviate edema, and reduce renal function impairment. In the model group, the protein expression of Cav-1 was upregulated, whereas VE-cadherin was downregulated, accompanied by the suppression of p-eNOS expression and activation of the PI3K pathway. Meanwhile, an increased NO level in both serum and kidney tissues was observed, and the above situations were improved with YBT intervention. It thus indicates YBT exerts therapeutic effects on the edema of nephrotic syndrome, as it improves the hyperpermeability of renal microvasculature, and that YBT is engaged in the regulation of Cav-1/eNOS pathway-mediated endothelial function.

Inhibition of Importin-α-mediated Nuclear Localization of Dendrin Attenuates Podocyte Loss and Glomerulosclerosis.

Nuclear translocation of dendrin is observed in the glomeruli in numerous human renal diseases, but the mechanism remains unknown. This study investigated that mechanism and its consequence in podocytes. The effect of dendrin deficiency was studied in adriamycin (ADR)- nephropathy model and membrane-associated guanylate kinase inverted 2 ( MAGI2) podocyte-specific knockout ( MAGI2 podKO) mice. The mechanism and the effect of nuclear translocation of dendrin were studied in podocytes overexpressing (OE) full-length dendrin and nuclear localization signal 1 (NLS1)- deleted dendrin. Ivermectin was used to inhibit importin-α. Dendrin ablation reduced albuminuria, podocyte loss, and glomerulosclerosis in ADR-induced nephropathy and MAGI2 podKO mice. Dendrin deficiency also prolonged the lifespan of MAGI2 podKO mice. Nuclear dendrin promoted JNK phosphorylation that subsequently altered focal adhesion, reducing cell attachment and enhancing apoptosis in cultured podocytes. Classical bipartite NLS sequence and importin-α mediate nuclear translocation of dendrin. The inhibition of importin-α/β reduced dendrin nuclear translocation and apoptosis in vitro as well as albuminuria, podocyte loss, and glomerulosclerosis in ADR-induced nephropathy and MAGI2 podKO mice. Importin-α3 colocalized with nuclear dendrin in the glomeruli of focal segmental glomerulosclerosis and IgA nephropathy patients. Nuclear translocation of dendrin promotes cell detachment-induced apoptosis in podocytes. Therefore, inhibiting importin-α-mediated dendrin nuclear translocation is a potential strategy to prevent podocyte loss and glomerulosclerosis.

Deciphering the pharmacological mechanisms of Rostellularia procumbens (L) Nees. Extract alleviates adriamycin‐induced nephropathy in vivo and in vitro

BackgroundRostellularia procumbens (L) Nees. is an effective traditional Chinese herbal medicine for the treatment of patients with chronic glomerulonephritis (CGN) in the clinic. However, the underlying molecular mechanisms need further elucidation. PurposeThis study aims to investigate the renoprotective mechanisms of n-butanol extract from Rostellularia procumbens (L) Nees. (J-NE) in vivo and in vitro. MethodsThe components of J-NE were analyzed by UPLC-MS/MS. In vivo, the nephropathy model was induced in mice by tail vein injection with adriamycin (10 mg·kg−1), and mice were treated with vehicle or J-NE or benazepril by daily gavage. In vitro, MPC5 cells exposed to adriamycin (0.3 μg/ml) were treated with J-NE. The effects of J-NE inhibit podocyte apoptosis and protect against adriamycin-induced nephropathy were determined by Network pharmacology, RNA-seq, qPCR, ELISA, immunoblotting, flow cytometry, and TUNEL assay, according to the experimental protocols. ResultThe results showed that treatment significantly improved ADR‐induced renal pathological changes, and the therapeutic mechanism of J-NE was related to the inhibition of podocyte apoptosis. Further molecular mechanism studies found that J-NE inhibited inflammation, increase the proteins expression levels of Nephrin and Podocin, reduce TRPC6 and Desmin expression levels and calcium ion levels in podocytes, and decrease the proteins expression levels of PI3K, p-PI3K, Akt and p-Akt to attenuated apoptosis. Furthermore, 38 compounds of J-NE were identified. ConclusionJ-NE exerted the renoprotective effects by inhibiting podocyte apoptosis, which provides effective evidence for the treatment of J-NE targeting renal injury in CGN.

Capsazepine (CPZ) Inhibits TRPC6 Conductance and Is Protective in Adriamycin-Induced Nephropathy and Diabetic Glomerulopathy.

Reactive oxygen species (ROS), which excessively arise in diabetes and systemic inflammatory diseases, modify cellular lipids and cellular lipid composition leading to altered biophysical properties of cellular membranes. The impact of lipid peroxidation on transmembrane signaling routes is not yet well studied. The canonical transient receptor potential channel 6 (TRPC6) is implicated in the pathogenesis of several forms of glomerular diseases. TRPC6 is sensitive to membrane stretch and relies on a distinct lipid environment. This study investigates the effect of oxidative alterations to plasma membrane lipids on TRPC6 activity and the function of the glomerular filter. Knockout of the anti-oxidative, lipid modifying enzyme paraoxonase 2 (PON2) leads to altered biophysical properties of glomerular epithelial cells, which are called podocytes. Cortical stiffness, quantified by atomic force microscopy, was largely increased in PON2-deficient cultured podocytes. PON2 deficiency markedly enhanced TRPC6 channel currents and channel recovery. Treatment with the amphiphilic substance capsazepine in micromolar doses reduced cortical stiffness and abrogated TRPC6 conductance. In in vivo studies, capsazepine reduced the glomerular phenotype in the model of adriamycin-induced nephropathy in PON2 knockout mice and wildtype littermates. In diabetic AKITA mice, the progression of albuminuria and diabetic kidney disease was delayed. In summary, we provide evidence that the modification of membrane characteristics affects TRPC6 signaling. These results could spur future research to investigate modification of the direct lipid environment of TRPC6 as a future therapeutic strategy in glomerular disease.

TYRO3 agonist as therapy for glomerular disease.

Podocyte injury and loss are key drivers of primary and secondary glomerular diseases, such as focal segmental glomerulosclerosis (FSGS) and diabetic kidney disease (DKD). We previously demonstrated the renoprotective role of protein S (PS) and its cognate tyrosine-protein kinase receptor, TYRO3, in models of FSGS and DKD and that their signaling exerts antiapoptotic and antiinflammatory effects to confer protection against podocyte loss. Among the 3 TAM receptors (TYRO3, AXL, and MER), only TYRO3 expression is largely restricted to podocytes, and glomerular TYRO3 mRNA expression negatively correlates with human glomerular disease progression. Therefore, we posited that the agonistic PS/TYRO3 signaling could serve as a potential therapeutic approach to attenuate glomerular disease progression. As PS function is not limited to TYRO3-mediated signal transduction but includes its anticoagulant activity, we focused on the development of TYRO3 agonists as an optimal therapeutic approach to glomerular disease. Among the small-molecule TYRO3 agonistic compounds screened, compound 10 (C-10) showed a selective activation of TYRO3 without any effects on AXL or MER. We also confirmed that C-10 directly binds to TYRO3, but not the other receptors. In vivo, C-10 attenuated proteinuria, glomerular injury, and podocyte loss in mouse models of Adriamycin-induced nephropathy and a db/db model of type 2 diabetes. Moreover, these renoprotective effects of C-10 were lost in Tyro3-knockout mice, indicating that C-10 is a selective agonist of TYRO3 activity that mitigates podocyte injury and glomerular disease. Therefore, C-10, a TYRO3 agonist, could be potentially developed as a new therapy for glomerular disease.

Differences in susceptibility to ADR nephropathy among C57BL/6 substrains.

Adriamycin (ADR) nephropathy is the most widely used nephropathy model to study the pathophysiological mechanisms of chronic kidney disease (CKD) in mice. However, its application is limited to a few mouse strains such as the BALB/c strain; the standard strain, C57BL/6J (B6J), does not develop ADR nephropathy. Nevertheless, Arif et al. reported that C57BL/6N (B6N), another standard strain, is ADR-susceptible. Since then, no follow-up reports or other studies have been published on ADR nephropathy in B6N mice. Therefore, the goal of this study was to determine whether B6N mice are indeed susceptible to ADR nephropathy and whether there are differences in ADR susceptibility among the substrains of C57BL/6NCrl (NCrl) and C57BL/6NJcl (NJcl). NCrl mice showed marked albuminuria and mesangial cell proliferation, which are associated with mild ADR nephropathy, confirming that NCrl mice were susceptible to ADR nephropathy. On the other hand, NJcl mice did not exhibit these symptoms. ADR nephropathy models are usually generated by administering ADR through the tail vein, but Arif et al. administered ADR through the orbital vein. Therefore, we investigated the effect of the route of administration on ADR nephropathy. The degree of ADR nephropathy was found to vary based on the route of administration: more severe nephropathy was observed upon administration through the tail vein than through the orbital vein. Therefore, we conclude that NCrl mice are susceptible to ADR nephropathy, and the severity of ADR-induced nephropathy through orbital vein administration is relatively lower than that through the tail vein.

Susceptibility to adriamycin-induced hepatotoxicity in mice depends on PRKDC polymorphism.

Adriamycin (ADR) is an effective chemotherapy drug for various cancers but has serious side effects. ADR-induced liver damage is a common problem during therapy, but the underlying mechanism remains to be fully understood. In contrast, ADR-induced glomerular damage is well studied in rodents, and sensitivity to ADR-induced nephropathy is because of the R2140C polymorphism of Prkdc gene. To investigate whether strain differences or sensitivity to ADR-induced liver damage are related to Prkdc polymorphism, this study compared the sensitivity to ADR-induced liver damage among C57BL/6J (B6J), B6-PrkdcR2140C, and BALB/c mice. Although B6J exhibits resistance to ADR-induced liver injury, BALB/c and B6-PrkdcR2140C are more susceptible to liver injury, which is exacerbated by the presence of R2140C mutation in PRKDC.

Paricalcitol Improves the Angiopoietin/Tie-2 and VEGF/VEGFR2 Signaling Pathways in Adriamycin-Induced Nephropathy.

Renal endothelial cell (EC) injury and microvascular dysfunction contribute to chronic kidney disease (CKD). In recent years, increasing evidence has suggested that EC undergoes an endothelial-to-mesenchymal transition (EndoMT), which might promote fibrosis. Adriamycin (ADR) induces glomerular endothelial dysfunction, which leads to progressive proteinuria in rodents. The activation of the vitamin D receptor (VDR) plays a crucial role in endothelial function modulation, cell differentiation, and suppression of the expression of fibrotic markers by regulating the production of nitric oxide (NO) by activating the endothelial NO synthase (eNOS) in the kidneys. This study aimed to evaluate the effect of paricalcitol treatment on renal endothelial toxicity in a model of CKD induced by ADR in rats and explore mechanisms involved in EC maintenance by eNOS/NO, angiopoietins (Angs)/endothelium cell-specific receptor tyrosine kinase (Tie-2, also known as TEK) and vascular endothelial growth factor (VEGF)-VEGF receptor 2 (VEGFR2) axis. The results show that paricalcitol attenuated the renal damage ADR-induced with antiproteinuric effects, glomerular and tubular structure, and function protection. Furthermore, activation of the VDR promoted the maintenance of the function and structure of glomerular, cortical, and external medullary endothelial cells by regulating NO production. In addition, it suppressed the expression of the mesenchymal markers in renal tissue through attenuation of (transforming growth factor-beta) TGF-β1/Smad2/3-dependent and downregulated of Ang-2/Tie-2 axis. It regulated the VEGF/VEGFR2 pathway, which was ADR-deregulated. These effects were associated with lower AT1 expression and VDR recovery to renal tissue after paricalcitol treatment. Our results showed a protective role of paricalcitol in the renal microvasculature that could be used as a target for treating the beginning of CKD.