Fibrosis in Chronic Kidney Disease: Pathogenesis and Consequences

Panaxatriol saponins exert anti-renal fibrosis by suppressing TNF-α mediated inflammation and TGF-β1/Smad3 signaling pathway

Renal fibrosis is a key pathological process in the progression of chronic kidney disease (CKD). Panaxatriol saponins (PTS), the main bioactive compounds extracted from Panax notoginseng (Burk.) F.H. Chen, have demonstrated antioxidative and anti-inflammatory activities. This study aimed to investigate the potential protective effects of PTS against renal fibrosis and explore the underlying pharmacological mechanisms. A unilateral ureteral obstruction (UUO) model was established in Sprague-Dawley (SD) rats to induce renal fibrosis. Histopathological changes were assessed using hematoxylin and eosin (HE) staining, Masson's trichrome staining, and transmission electron microscopy (TEM). Network pharmacology and molecular docking approaches were employed to identify potential signaling molecules through which PTS may mitigate renal fibrosis. Western blotting, quantitative real-time PCR (qRT-PCR), and immunohistochemistry were utilized to validate the involvement of specific signaling pathways in PTS-mediated anti-fibrotic effects. Our data demonstrated that PTS alleviated renal dysfunction and provided protective effects against renal fibrosis, primarily through the TNF-α and TGF-β1 signaling pathways. Moreover, PTS treatment significantly downregulated pro-inflammatory cytokines such as TNF-α, IL-6, and Smad3 activity. Additionally, PTS inhibited the expression of key fibrosis markers, including α-SMA, collagen I, and fibronectin. Our study suggests that PTS exert a prevention effect in renal fibrosis by blocking the TGF-β1/Smad3 signaling pathway.

Role of local complement activation in kidney fibrosis and repair

The complement system is an important component of the innate immune system involved in host defense and maintaining homeostasis. While the liver is the main source of complement proteins in the bloodstream, recent research has shown that various tissues, including the kidneys, can produce complement components locally in response to both acute and chronic inflammation. This Review highlights evidence from animal models of glomerular and tubulointerstitial kidney disease showing increased expression of intracellular complement in the kidneys. Studies using knockout mice for complement and complement receptors, along with complement inhibitors, have demonstrated that reduced complement activation in animal models of kidney fibrosis led to reduced inflammation and fibrosis, thereby supporting the pathogenic role of complement activation. Data from single-cell RNA-sequencing, spatial transcriptomics, and proteomics studies further demonstrate that alterations in local complement levels contribute to the fibrotic microenvironment observed in these models. Additionally, kidney biopsy results from patients with acute kidney injury and chronic kidney disease (CKD) indicate an increased expression of intracellular complement components as disease progresses. Developing drugs aimed at diminishing the expression and activation of local complement in glomerular and tubulointerstitial kidney disease could provide a novel approach to managing CKD.

Activation of mannose receptor C type 1 in macrophages improves renal fibrosis through mediating fibronectin endocytosis

AIMS

Excess extracellular matrix (ECM) deposition is the characteristic of renal fibrosis, owing to the imbalance between synthesis and degradation. Fibronectin could regulate the deposition of other ECM, thus plays a crucial role in the progression of renal fibrosis. Mannose receptor C type 1 (MRC1), largely expressed on macrophages, owns an extracellular fibronectin type II domain that binds to and internalizes collagen and thus involves in fibrosis modulation. The purpose of the present study was to investigate whether MRC1 participates in the internalization of fibronectin and whether alginate oligosaccharides (AOSC), a degradation product of alginate, has beneficial effects in the resolution of renal fibrosis via MRC1.

MATERIALS AND METHODS

Renal fibrosis models were constructed by unilateral ureteral obstruction (UUO) and unilateral ischemia-reperfusion injury (UIRI) in MRC1-WT and MRC1-KO mice. RAW264.7 cells were treated with TGF-β1 to induce pro-fibrotic responses. Expression of fibrotic markers and fibronectin endocytosis were examined.

KEY FINDINGS

MRC1 gene knockout aggravated renal fibrosis in UUO and UIRI models. Inhibition of MRC1 exacerbated TGF-β1-induced pro-fibrotic responses in RAW264.7 cells. MRC1 regulated integrin β1-mediated fibronectin endocytosis through Arp2/3-Kindlin-2 signaling pathway. AOSC improved renal fibrosis by increasing MRC1 expression and endocytosis of fibronectin.

SIGNIFICANCE

Our findings highlight the importance of MRC1 and fibronectin endocytosis in the development of renal fibrosis, suggesting that activation of MRC1 by AOSC is probably a therapeutic option to delay the progress of kidney fibrosis.

Aptamer-targeted anti-miR RNA construct based on 3WJ as a new approach for the treatment of chronic kidney disease in an experimental model

The treatment of chronic disease (CKD) is a great challenge in healthcare that requires an innovative approach to address its complex nature. RNA nanotechnology has emerged rapidly and received attention in the last few years because of its significant aptitude for therapies. Hence, the present study aimed to design, construct, and characterize a multifunctional (anti-miR-34a DNA aptamer-kidney targeted) RNA nanoparticle (RNPs) based on bacteriophage phi29 packaging RNA three-way junction (pRNA-3WJ), and then explore their in vivo toxicity and therapeutic potentials in mice model of CKD. After confirming the safety and specific targeting capability of the prepared core 3WJ (3WJ) and the therapeutic 3WJ (3WJ-Kapt/anti-miR-34a) RNPs to renal tissue using healthy mice, CKD was induced in C57BL/6 mice using adenine. CKD mice were treated with a single intravenous injection of 3WJ or 3WJ-Kapt/anti-miR-34a. Every week, 5 mice of each group were selected randomly for sample collection for 4 weeks post-treatment. The anti-miR-34a 3WJ-RNPs have shown stability, safety, and efficacy in renal targeting using DNA aptamer, by targeting miR-34a in renal tissue, 3WJ-Kapt/anti-miR-34a suppressed profibrotic gene expression and induced anti-fibrotic pathways' expression. Our present study provides preliminary and pioneering evidence for the promising treatment of renal fibrosis and CKD through targeting miR-34a in the renal tissue by 3WJ-RNPs. The CKD mice showed marked time-dependent up-regulation of the renal profibrotic pathways, including TGF-β, FGF2, and WNT/β-catenin pathways. The same mice showed suppressed renal expression of the antifibrotic pathways, including α and β Klotho, SMAD7, and SIRT1. The prepared anti-miR-34a 3WJ-RNPs have shown stability, safety, and efficacy in renal targeting using DNA aptamer. By targeting miR-34a in renal tissue, 3WJ-Kapt/anti-miR-34a suppressed profibrotic gene expression and induced anti-fibrotic pathways' expression. Our present study provides preliminary and pioneer evidence for the promising treatment of renal fibrosis and CKD through targeting miR-34a in the renal tissue by 3WJ-RNPs.

Time-dose response and mechanistic specificity of berberine in renal fibrosis from a multi-model integration perspective: a systematic review and meta-analysis on animal models

Objective

This research intends to comprehensively evaluate the efficacy of berberine (BBR) and the specificity of its mechanisms of action in different animal models of renal fibrosis through a multi-model integration strategy.

Methods

A comprehensive search of animal experimental studies was carried out across 10 different databases, including PubMed, Embase, Web of Science, Scopus, Cochrane Library, SCIELO, CNKI, Wanfang database, CBM and VIP Information Chinese Periodical Service Platform, spanning from their inception up to November 2024. The included studies' methodological quality was assessed using the SYRCLE's risk of bias tool for animal experiment, and statistical analyses were carried out with Stata 18.0.

Results

In total, 26 animal studies (2010-2024) were included, encompassing diverse models of renal fibrosis. The Meta-analysis revealed that BBR significantly lowered serum creatinine, blood urea nitrogen, α-SMA, and TGF-β1 levels, alongside reductions in renal fibrosis area and oxidative stress markers. The time-dose response analysis indicated that BBR was most efficacious within the 100-400 mg/kg dose range over a 5-12-week intervention period. Still, the mechanism of action was model-dependent: in the UUO model, BBR predominantly modulated the AMPK/PPARα pathway and ferroptosis, while in the DN model, it primarily targeted glycolipid metabolism and epigenetic regulation.

Conclusion

BBR significantly ameliorates renal fibrosis progression through a multi-targeted mechanism that is model-specific. Although preclinical evidence supports its therapeutic potential, the interpretation of the conclusions requires caution, considering the significant heterogeneity and methodological quality differences among the included experiments.

Systematic Review Registration

https://www.crd.york.ac.uk/, identifier CRD42024619202.

The threat of microplastics to human kidney health: Mechanisms of nephrotoxicity and future research directions

Following the inadequacy of global plastic pollution control measures, microplastic (MP) pollution is posing new challenges to human health. In recent years, MPs have been detected in various human tissues, including their first identification in human kidneys in 2023. MPs can reach the kidneys through inhalation, oral ingestion, and intravascular injection, and they can be excreted via urine. Based on the latest research, this article reviews the nephrotoxicity of MPs and proposes a filtration-reabsorption-translocation hypothesis regarding the potential renal excretion mechanism of MPs. Short-term exposure to MPs can induce oxidative stress, resulting in endoplasmic reticulum (ER) stress, inflammatory responses, and lipid metabolism disorders, while long-term exposure may result in renal fibrosis mediated by ferroptosis. The nephrotoxicity of MPs is associated with particle size, though not in a linear manner. A specific size range appears to exhibit more significant kidney toxicity. Furthermore, oral exposure may activate the complement system in the kidneys through the gut-kidney axis, with the C5a/C5aR pathway playing an important role in this process. In conclusion, MPs present a substantial threat to human kidney health. Considering the existing research limitations, it is imperative to urgently investigate the effects of MPs at realistic environmental exposure concentrations on human kidneys and to explore strategies for mitigating their nephrotoxicity.

Klotho Protein: A Multifaceted Guardian of Healthy Aging and Its Therapeutic Potential

The Klotho protein, encoded by the KL gene, has garnered significant attention as a pivotal biomolecule in the field of aging research. Its expression levels are closely correlated with both lifespan and overall health status, exerting influence over critical physiological processes such as metabolic homeostasis, oxidative stress response, and inflammation modulation. This review aims to systematically examine the multifaceted roles of Klotho within the context of aging and its implications for various age-associated disorders. We highlight the emerging evidence suggesting that Klotho may serve as a key regulator in age-related pathologies, including cardiovascular diseases, neurodegenerative disorders, and metabolic syndromes. Furthermore, we explore the potential of Klotho as a therapeutic target, positing that interventions aimed at enhancing Klotho activity could offer novel strategies for alleviating the health burdens experienced by the aging population.

Incidence and risk factors of new clinical disorders in patients with COVID-19 hyperinflammatory syndrome

This study investigated new incident clinical disorders in patients with COVID-19-related hyperinflammatory syndrome (cHIS) 3.5 years post infection. We analyzed 14,335 patients hospitalized with COVID-19 from March-2020 to July-2023. cHIS was defined based on a point system that included elevated body temperature, macrophage activation, hematological dysfunction, coagulopathy, and hepatic enzyme. Outcomes were newly diagnosed disorders of hypertension, diabetes, cardiovascular diseases, chronic kidney disease (CKD), chronic obstructive pulmonary disease (COPD), and asthma post COVID-19. Cumulative incidences and hazard ratios were computed. Compared to non-cHIS patients, cHIS patients were older, fewer female, more Blacks, higher prevalence of pre-existing comorbidities. Patients with cHIS had higher risk of developing cardiovascular disease (HR = 1.24 [1.04,1.47] p < 0.05), CKD (1.24 [1.01, 1.53] p < 0.05), and obesity (1.61 [1.31,1.98], p < 0.001) but not hypertension, diabetes, COPD, and asthma. Cumulative incidence analysis showed that patients ≥ 50 years old showed markedly higher new incidences of individual new disorders compared to patients < 50 years old. COVID-19 related hyperinflammatory syndrome confers a significantly higher risk for developing new common clinical disorders. Identifying risks for developing new clinical disorders in patients with COVID-19 related hyperinflammatory syndrome may encourage diligent follow-up of high-risk individuals.

Renal transplant ultrasound: assessment of complications and advanced applications

Renal transplantation is the most commonly performed solid organ transplant procedure. Monitoring renal transplants with ultrasound is a critical component in the management of transplant patients both in the immediate aftermath of surgery and longitudinally. Many complications are detectable via ultrasound evaluation with relative prevalence dependent on the time since surgery. It is critical for the practicing radiologist to recognize these complications to help guide appropriate treatment. Fundamental understanding of the procedure, including various surgical techniques is of great importance. In this article, the sonographic findings of the most common postoperative and long-term complications of renal transplantation are reviewed. As complications are highly related to surgical technique, the most common surgical techniques are presented first. Comprehensive ultrasound evaluation of the allograft is discussed next, followed by extensive review of the ultrasound findings of common complications. Finally, select recent advances in ultrasound are presented with their current and potential applications to renal transplant evaluation.

Mesenchymal Stem Cells Mediated Suppression of GREM2 Inhibits Renal Epithelial-Mesenchymal Transition and Attenuates the Progression of Diabetic Kidney Disease

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease worldwide. Despite advancements in various treatments, the prevalence of DKD continues to rise, leading to a significant increase in the demand for dialysis and kidney transplantation. This study aimed to evaluate the effects of a Small cell＋Ultra Potent＋Scale UP cell (SMUP-Cell), a type of human umbilical cord blood-derived mesenchymal stem cell, on DKD in the db/db mouse model of type 2 diabetes mellitus. After administering SMUP-Cells via tail vein injection in db/db mice, the animals were monitored over a three-month period. The db/db mice exhibited an increased urine albumin-to-creatinine ratio (UACR). However, the administration of SMUP-Cells resulted in a reduction of the UACR. The expression levels of desmin, α-smooth muscle actin, and fibronectin-markers of epithelial-mesenchymal transition (EMT)-as well as kidney injury molecule 1, a sensitive marker of tubular injury, were significantly elevated in db/db mice. Treatment with SMUP-Cells ameliorated all of these changes. Notably, Gremlin isoform 2 (Grem2) exhibited the most significant difference in expression according to the transcriptome analysis. The elevated expression of Grem2 in db/db mice was significantly reduced following SMUP-Cell treatment. In vitro, treatment with high glucose and cholesterol induced Grem2 expression in renal tubular epithelial cells (RTECs), while Grem2 knockdown effectively prevented fibrosis and senescence induced by high glucose and cholesterol in RTECs. These observations suggest that SMUP-Cells inhibit the progression of DKD by inhibiting EMT through the reduction of Grem2 expression in RTECs.

Multiplatform Metabolomic Profiling of the Unilateral Ureteral Obstruction Murine Model of CKD

In chronic kidney disease (CKD) research, animal models such as the unilateral ureteral obstruction (UUO) rodent model are crucial to understanding disease progression, particularly renal fibrosis. Despite its widespread use, the molecular mechanisms driving CKD remain incompletely understood. Given the interplay between metabolism and fibrosis, a comprehensive metabolomic analysis of UUO renal tissue is necessary. This study involved untargeted multiplatform analysis using liquid chromatography (LC), gas chromatography (GC), and capillary electrophoresis (CE) coupled with mass spectrometry (MS) to examine murine kidney tissue from the UUO model. The results highlight metabolic changes associated with tubulointerstitial fibrosis, which affect pathways such as the tricarboxylic acid (TCA) cycle, the urea cycle, and lipid metabolism. In particular, fibrosis impacts the lipidomic profile, with decreases in most lipid classes and increases in specific glycerophospholipids, hexosylceramides, and cholesterol esters. These findings demonstrate the value of a multiplatform approach in elucidating metabolic alterations in CKD, providing information on the underlying molecular mechanisms and paving the way for further research.

Endogenous Galectin-8 protects against Th17 infiltration and fibrosis following acute kidney injury

BACKGROUND

Acute kidney injury (AKI) is a serious clinical condition characterized by a rapid decline in renal function, often progressing to chronic kidney disease (CKD) and fibrosis. The endogenous mechanisms influencing kidney injury resolution or maladaptive repair remain poorly understood. Galectin-8 (Gal-8), a tandem-repeat β-galactoside-binding lectin, plays a role in epithelial cell proliferation, epithelial-mesenchymal transition, and immune regulation, all of which are critical in AKI outcomes. While exogenous Gal-8 administration has shown renoprotective effects, its endogenous role in kidney injury progression and resolution remains unclear.

METHODS

To investigate the endogenous role of Gal-8 in AKI, we compared the responses of Gal-8 knockout (Gal-8-KO; Lgals8-/- bearing a β-gal cassette under the Lgals8 gene promoter) and wild-type (Lgals8+/+) mice in a nephrotoxic folic acid (FA)-induced AKI model. Renal Gal-8 expression was assessed by β-galactosidase staining, lectin-marker colocalization, and RT-qPCR. Renal function, structure, and immune responses were evaluated at the acute (day 2) and fibrotic (day 14) phases of injury. Plasma creatinine levels were measured to assess renal function, while histological analyses evaluated tubular damage, renal inflammation, and extracellular matrix deposition. Flow cytometry was performed to characterize the immune response, focusing on pro-inflammatory T cells.

RESULTS

Galectin-8 was predominantly expressed in the renal cortex, localizing to tubules, glomeruli, and blood vessels, with its levels decreasing by half following AKI. Both Lgals8+/+ and Lgals8-/- mice exhibited similar renal function and structure impairments during the acute phase, though Lgals8+/+ mice showed slightly worse damage. By the fibrotic phase, Lgals8-/- mice exhibited more pronounced cortical damage and fibrosis, characterized by increased type I and III collagen deposition and enhanced Th17 cell infiltration, while myofibroblast activation remained comparable to that of Lgals8+/+ mice.

CONCLUSIONS

Endogenous Gal-8 does not significantly protect the kidney during the acute phase and is dispensable for cell proliferation and death in response to AKI. However, it is crucial in preventing maladaptive repair by regulating extracellular matrix homeostasis and mitigating fibrosis. Additionally, Gal-8 contributes to inflammation resolution by limiting persistent immune cell infiltration, particularly IL-17-secreting cells.

ShenQi ShenKang Granule Alleviates Chronic Kidney Disease by Inhibiting the PI3K/AKT/mTOR Pathway and Restoring Autophagy Flux and Mitochondrial Integrity

Purpose

This study investigates the effect of Shenqi Shenkang granule (SQSKG) on chronic kidney disease (CKD), focusing on regulating the PI3K/AKT/mTOR pathway, autophagy, and mitochondrial homeostasis.

Methods

The compounds and targets of SQSKG on CKD were identified by network pharmacology and validated by molecular docking. LC-MS/MS was used to verify the compounds screened by network pharmacology. In vitro experiments based on HK-2 cells were used to assess its impact on cell migration, viability, oxidative stress, and key proteins of the PI3K/AKT/mTOR pathway, autophagy, and fibrosis. Mitochondrial function and autophagic flux were evaluated via JC-1, Mito-Tracker, and Ad-mCherry-GFP-LC3B assays. In vivo, an adenine-induced CKD rat model was used to analyze renal function, fibrosis, and autophagy through serum/urine tests, histology, and immunofluorescence.

Results

Network pharmacology identified 49 compounds and 149 targets associated with SQSKG's therapeutic effects on CKD, highlighting critical targets such as AKT1, MAPK1, EGFR, HSP90AA, and IGF1R. The primary mechanism involves the PI3K/AKT pathway. In vitro experiments demonstrated that SQSKG significantly enhanced cell migration, colony formation, viability in AGEs-treated HK-2 cells, and exhibited robust antioxidant properties by increasing SOD levels and reducing MDA and ROS production. SQSKG effectively inhibited the phosphorylation of PI3K, AKT, and mTOR, and reduced TGF-β fluorescence intensity in kidney tissue. Autophagic flux analysis showed that SQSKG increased autophagic activity and reduced p62 accumulation. Additionally, JC-1 and Mito-Tracker Green assays demonstrated that SQSKG improved mitochondrial membrane potential and morphology. In vivo, SQSKG significantly improved renal function and alleviated renal fibrosis in a dose-dependent manner, reversing fibrosis marker overexpression (Col-I, α-SMA, TGF-β) and activating autophagy.

Conclusion

Our findings provide novel insights into the therapeutic potential of SQSKG in CKD management, highlighting its ability to modulate PI3K/AKT/mTOR pathway, activating autophagy flux, and restoring mitochondrial integrity, thereby offering a promising complementary or alternative treatment option for patients with CKD.

HNF3α Targets Nckap1l and Promotes Renal Fibrosis Following Ischemia-Reperfusion Injury

Chronic Kidney Disease (CKD) is a global health challenge, with acute kidney injury (AKI) from ischemia-reperfusion injury (IRI) as a common cause. This study explored the role of Hepatocyte Nuclear Factor 3 alpha (HNF3α/FOXA1) in renal fibrosis and CKD after IRI. Kidney biopsy specimens from CKD patients and mouse models (IRI or unilateral ureteral obstruction) showed HNF3α upregulation in fibrotic kidneys, linked to renal function decline. Additional experiments demonstrated that deletion of HNF3α mitigated IRI-induced renal fibrosis, and that overexpression of HNF3α led to increased fibrosis. Examination of the potential mechanism by transcriptome sequencing and CUT&Tag sequencing suggested that HNF3α promoted renal fibrosis by increasing the expression of the NCK associated protein 1 like (Nckap1l, formerly known as hematopoietic protein 1 [Hem1]), a vital component of the WAVE complex which plays a significant role in cytoskeletal regulation and cell migration. These results underscore the critical function of HNF3α in renal fibrosis following IRI, and also identify Nckap1l as a potential therapeutic target, thus opening new avenues for research and potential therapeutic interventions for CKD and renal fibrosis.

Raspberry ameliorates renal fibrosis in rats with chronic kidney disease via the PI3K/Akt pathway

BACKGROUND

Renal fibrosis is a hallmark of chronic kidney disease (CKD). In traditional Chinese medicine, Rubus chingii Hu (raspberry) is believed to have kidney-tonifying properties. However, whether raspberry can effectively treat CKD, along with the specific active compounds and underlying mechanisms, remains unclear.

PURPOSE

This study aims to investigate the potential of raspberries in treating CKD and elucidate the mechanisms involved.

METHODS

CKD model was established in rats using adenine. The effects of raspberry treatment on CKD were assessed through macroscopic observations and pathological changes in the kidney. The expression of fibrotic proteins in renal tissues was analyzed to evaluate the impact of raspberry on renal fibrosis. Data mining combined with compositional analysis were employed to identify the active ingredients, targets, and pathways of raspberry that may improve CKD. Subsequently, Western blotting and immunofluorescence analysis were conducted to confirm the involvement of the PI3K/AKT signaling pathway in the renoprotective mechanism of raspberry.

RESULTS

Raspberry treatment significantly alleviated renal pathological damage, fibrosis and inflammation in model rats, showing effects comparable to irbesartan (Avapro). Chemical composition analysis and network pharmacology predicted AKT1 as the core target, and the PI3K/AKT pathway plays a pivotal role in mediating the therapeutic effects of raspberry extract in CKD. Molecular docking studies further confirmed that active compounds in raspberry have a strong binding affinity with AKT1. Western blotting and immunofluorescence results demonstrated that raspberry inhibited phosphorylation, thereby suppressing the PI3K/AKT pathway, leading to its antifibrotic effect on the kidney.

CONCLUSION

Raspberry was firstly discovered to potentially treat CKD by alleviating renal fibrosis through inhibition of the PI3K/AKT pathway. Raspberry, as a medicinal and edible traditional herb, could serve as a promising therapeutic agent or health supplement for improving renal fibrosis and slowing CKD progression.

Perturbed gut microbiota and serum metabolites are associated with progressive renal fibrosis

Introduction

The intricate pathogenesis of renal fibrosis necessitates identifying biomarkers at various stages to facilitate targeted therapeutic interventions, which would enhance patient survival rates and significantly improve prognosis.

Methods

We investigated the changes in gut microbiota and serum metabolites during the early, middle, and late stages of renal fibrosis in rats using 16S rDNA sequencing and UPLC-QTOF/MS-based metabolomics.

Results

We identified 5, 21, and 14 potential gut microbial markers and 19, 23, and 31 potential metabolic markers in the MOD1, MOD2, and MOD4 groups, respectively. Bifidobacterium was identified as a shared microbial marker between the MOD1 and MOD2 groups; Prevotellaceae_NK3B31_group and Bacteroides were identified as shared microbial markers between the MOD2 and MOD4 groups. The pathways of arachidonic acid metabolism and retinol metabolism were found to play a significant role in the modulation of renal fibrosis at 1, 2, and 4 weeks. Notably, the metabolic biomarkers 8,9-EET and 5(S)-HPETE within these pathways emerged as critical determinants influencing renal fibrosis.

Discussion

Our findings demonstrated that the severity of renal fibrosis is associated with dysbiosis of the gut microbiota and alterations in serum metabolites.

The Effect of Increased Plant Protein Intake on the Lipid Profile of Chronic Kidney Disease Patients: A Meta-Analysis of Controlled Clinical Trials

Background/Objectives: Chronic kidney disease (CKD) is associated with increased mortality, with cardiovascular disease (CVD) being the primary cause of death. Proper lipid regulation may reduce CVD risk and slow CKD progression. While there is evidence that a higher plant protein intake could ameliorate lipid levels in the general population, the effects of this dietary regimen within the CKD population remain uncertain, with studies providing conflicting results. We aim to investigate the impact of increased plant protein intake on the lipid levels of CKD patients. Methods: Two electronic databases (PubMed, Scopus) were reviewed for controlled clinical trials assessing the effect of increased plant protein intake versus the usual CKD animal-based diet in CKD patients, published until June 2024. Results: Eleven trials, encompassing 248 patients, were included in this meta-analysis. Overall, compared to the usually recommended CKD diet, increased plant protein intake was associated with statistically significant reductions in total cholesterol (-24.51 mg/dL, 95% CI -40.33, -8.69), low-density lipoprotein (LDL) (-21.71 mg/dL, 95% CI -38.32, -5.1), triglycerides (- 21.88 mg/dL, 95% CI -35.34, -8.40), and Apolipoprotein B levels (-11.21 mg/dL, 95% CI -18.18, -4.25). No significant changes were observed in high-density lipoprotein (HDL) (0.09 mg/dL, 95% CI -1.82, 1.99) and Apolipoprotein A levels (0.04 mg/dL, 95% CI -7.14, 7.21). Conclusions: Increased plant protein intake, mainly from soy, reduces total cholesterol, LDL, triglycerides, and ApoB in adult CKD patients. Further research is needed to assess these effects in dialysis patients and explore non-soy plant sources.

Histone deacetylases and their inhibitors in kidney diseases

Histone deacetylases (HDACs) have emerged as key regulators in the pathogenesis of various kidney diseases. This review explores recent advancements in HDAC research, focusing on their role in kidney development and their critical involvement in the progression of chronic kidney disease (CKD), acute kidney injury (AKI), autosomal dominant polycystic kidney disease (ADPKD), and diabetic kidney disease (DKD). It also discusses the therapeutic potential of HDAC inhibitors in treating these conditions. Various HDAC inhibitors have shown promise by targeting specific HDAC isoforms and modulating a range of biological pathways. Their protective effects include modulation of apoptosis, autophagy, inflammation, and fibrosis, underscoring their broad therapeutic potential for kidney diseases. However, further research is essential to improve the selectivity of HDAC inhibitors, minimize toxicity, overcome drug resistance, and enhance their pharmacokinetic properties. This review offers insights to guide future research and prevention strategies for kidney disease management.

The association of non-exercise estimated cardiorespiratory fitness with hypertension and all-cause mortality in American and Chinese populations: evidence from NHANES and CHARLS

Background

The Non-Exercise Estimated Cardiorespiratory Fitness (NEE-CRF) method has gained attention in recent years due to its simplicity and effectiveness. Hypertension and all-cause mortality are significant public health issues worldwide, highlighting the importance of exploring the association between NEE-CRF and these two conditions.

Methods

The data from the National Health and Nutrition Examination Survey (NHANES) and the China Health and Retirement Longitudinal Study (CHARLS) were utilized to validate the association between NEE-CRF and hypertension as well as all-cause mortality. NEE-CRF was calculated using a sex-specific longitudinal non-exercise equation. To investigate the relationship between hypertension and all-cause mortality, multivariable regression analysis, generalized additive models, smooth curve fittings, and threshold effect analysis were employed. Logistic regression was used for hypertension analysis, while Cox proportional hazards regression was applied for all-cause mortality. Additionally, we conducted stratified analyses and interaction tests among different groups.

Results

In the NHANES, after fully adjusting for covariates, each unit increase in NEE-CRF was associated with a 24% reduction in the risk of hypertension (OR: 0.76, 95% CI: 0.74-0.78) and a 12% reduction in the risk of all-cause mortality (HR: 0.88, 95% CI: 0.79-0.86). Subgroup analyses showed that the relationship between NEE-CRF and both hypertension and all-cause mortality remained negatively correlated across different subgroups. The negative association was also validated in the CHARLS.

Conclusions

Higher NEE-CRF levels may reduce the risk of developing hypertension and all-cause mortality.

Endoplasmic reticulum stress aggravates ferroptosis via PERK/ATF4/HSPA5 pathway in UUO-induced renal fibrosis

Renal fibrosis, resulting from the transformation of damaged tubular epithelial cells (TECs), serves as a prevalent pathological condition observed in nearly all forms of advancing chronic kidney disease (CKD). Although crucial in fibrotic diseases, the association between endoplasmic reticulum stress (ERS) and ferroptosis remains incompletely elucidated. Herein, increased levels of heat shock protein family A member 5 (HSPA5), acting as a co-molecular in ERS and ferroptosis, along with EMT-associated alterations, including increased α-smooth muscle actin (α-SMA) and Col1a1 levels and decreased E-cad expression, were observed in fibrotic kidneys of Unilateral Ureteral Obstruction (UUO)-induced mouse models and TGF-β-induced EMT in HK-2 cells. The employment of ferrostatin-1 (Fer-1) improved these alterations and reversed TGF-β-induced EMT in vitro. More importantly, Inhibiting ERS by Tauroursodeoxycholate (TUDCA) reversed the alterations of ferroptosis, including GPX4 expression, reactive oxygen species (ROS) accumulation, iron overload, increased lipid peroxidation production, as well as EMT progression in vivo and in vitro. Whereas the overexpression of HSPA5 strikingly attenuated the inhibitory effects of TUDCA on ferroptosis and TGF-β-induced EMT in vitro. Mechanistically, Co-immunoprecipitation (Co-IP) tests showed that ATF4 engaged with and SUMOylated HSPA5 to trigger the HSPA5 signaling pathway in response to TGF-β. These findings illuminate that focusing on HSPA5 may present a promising therapeutic approach to enhance tubular epithelial cells' survival and alleviate the progression of CKD.

Wnt/β-catenin Pathway Aggravates Renal Fibrosis by Activating PUM2 Transcription to Repress YME1L-mediated Mitochondrial Homeostasis

Chronic kidney disease (CKD) affects more than 10% of people worldwide and is a leading cause of death. However, the pathogenesis of CKD remains elusive. The oxidative stress and mitochondrial membrane potential were detected using Enzyme-linked immunosorbent assay and JC-1 assay. Co-immunoprecipitation, dual-luciferase assay, chromatin IP, RNA IP and RNA pull-down were used to validate the interactions among genes. Exploiting a H2O2-induced fibrosis model in vitro, PUM2 expression was upregulated in Human kidney 2 cell (HK-2) cells, along with reduced cell viability, enhanced oxidative stress, impaired mitochondrial potential, and upregulated expressions of fibrosis-associated proteins. While PUM2 knockdown reversed the H2O2-induced injury in HK-2 cells. Mechanically, Wnt/β-catenin pathway activated PUM2 transcription via TCF4. It was further identified that Wnt/β-catenin pathway inhibited YME1L expression through PUM2-mediated destabilizing of its mRNA. PUM2 aggravated H2O2-induced oxidative stress, mitochondrial dysfunction, and renal fibrosis in HK-2 cell via suppressing YME1L expression. Our study revealed that Wnt/β-catenin aggravated renal fibrosis by activating PUM2 transcription to repress YME1L-mediated mitochondrial homeostasis, providing novel insights and potential therapeutic targets for the treatment of kidney fibrosis.

Ultrasonic renal length as an indicator of renal fibrosis severity in non-diabetic patients with chronic kidney disease

BACKGROUND

Debate continues regarding the potential of the ultrasonic renal length to serve as an indicator for evaluating the advancement of renal fibrosis in chronic kidney disease (CKD). This study investigates the independent association between renal length and renal fibrosis in non-diabetic CKD patients and assesses its diagnostic performance.

METHODS

From April 2019 to December 2021, 144 non-diabetic patients diagnosed with CKD who underwent a renal ultrasound examination and kidney biopsy were prospectively enrolled. Patients were categorized into the mild fibrosis group (n = 70) and the moderate-severe group (n = 74) based on the extent of fibrotic involvement. Ultrasonic renal length was measured from pole-to-pole in the coronal plane. A receiver operating characteristic (ROC) curve, multivariable logistic regression analysis, and a generalized additive model were performed.

RESULTS

A negative linear correlation was found between renal length and moderate-severe renal fibrosis risk. Each centimeter increase in renal length decreased the odds of moderate-severe fibrosis by 38% (OR: 0.62; 95% CI 0.41-0.93; P = 0.020). After adjusting for confounders, the relationship persisted (OR: 0.58; 95% CI 0.33-1.00; P = 0.048). However, renal length presented limited discrimination ability in distinguishing degrees of renal fibrosis while controlling the key confounding factors, yielding an area under the ROC curve of only 0.58 (95% CI 0.45-0.70).

CONCLUSION

While an inverse relationship exists between renal length and risk of having moderate-severe renal fibrosis in non-diabetic CKD patients, renal length alone is insufficient for diagnosing fibrosis severity, underscoring the need for additional diagnostic parameters in CKD assessment.

Renal and Peripheral Blood Transcriptome Signatures That Predict Treatment Response in Proliferative Lupus Nephritis-A Prospective Study

Mechanisms contributing to non-response to treatment in lupus nephritis (LN) are unclear. We characterised the transcriptome of paired peripheral blood mononuclear cells (PBMCs) and renal tissues in LN before and after cyclophosphamide (CYC) treatment and identified markers that predicted treatment response. Total RNA isolated from paired PBMCs (n = 32) and renal tissues (n = 25) of 16 proliferative LN before CYC treatment, 6 months post-treatment, and during renal flare, was sequenced on Illumina Novaseq-6000 platform. Post-treatment, eight patients were clinical responders (CR), of whom four flared (FL), and eight were non-responders (NR). Comparative transcriptomic analyses before and after treatment within CR, NR, and FL groups was performed using DESeq2. Weighted gene co-expression network analysis (WGCNA) and ROC analysis was performed to identify and validate hub genes predictive of treatment response. Based on this, we observed that pathways such as degradation of cell cycle proteins, expression of G0 and G1 phase proteins, and apoptosis, were upregulated in CR PBMCs post-treatment, while IFN-γ signalling and ECM organisation were downregulated. In NR PBMCs, ECM molecules, neddylation and BCR signalling were upregulated post-CYC treatment, while in NR renal tissue, TLR, IFN and NF-κB signalling pathways were upregulated. In FL PBMCs, neutrophil degranulation and ROS and RNS production in phagocytes were downregulated following treatment, whereas, in the corresponding renal tissue, cell-ECM interactions and ISG15 antiviral mechanism were downregulated. After WGCNA and subsequent ROC analysis, TENM2, NLGN1 and AP005230.1 from PBMCs each predicted NR (AUC-0.91; p = 0.03), while combined model improved prediction (AUC-0.94; p = 0.02). AP005230.1 from renal tissue also predicted non-response (AUC-0.94; p = 0.01) and AC092436.3 from PBMCs predicted renal flare (AUC-0.81; p = 0.04). Our study identified significant DEGs/pathways specific to different treatment outcomes and hub genes that predicted non-response and renal flare.

Effects of Deoxynivalenol Contamination on Growth Performance, Blood Biochemistry, Histology, Metabolomics, and the Microbiota: A Subacute Dose Oral Toxicity Study in Rats

Deoxynivalenol (DON), one of the most common mycotoxins, is frequently found in foods. This study investigated the effects of orally administered DON on the blood biochemical parameters, growth performance, histology, microbial composition, and metabolism of rats. After a 1-week adaptation period, 4-week-old rats were administered 0.9% saline (control), 1 mg/L DON (T1), 10 mg/L DON (T2), or 50 mg/L DON (T3) by gavage for 49 days. The DON-treated groups had significantly lower body weights than the control group (p < 0.05). Blood alkaline phosphatase, phosphate, cholesterol, amylase, and creatinine levels differed significantly between the DON-treated and control groups (p < 0.05). With increasing DON doses, fibrosis and apoptosis were observed in several tissues. In terms of metabolites, the bile acid biosynthesis pathway emerged as a potential biomarker, while the tryptophan metabolism pathway was found to be the most affected. The fecal microbiota showed significant differences in both alpha and beta diversity between the DON-treated and control groups (p < 0.05). In the cecal and fecal microbiota, the relative abundance of Firmicutes increased in the control and T1 groups, whereas Bacteroidota and Campylobacterota were more abundant in the T2 and T3 groups. In conclusion, our results showed that high DON exposure induces several dose-dependent adverse effects on rats.

Exploring disulfiram mechanisms in renal fibrosis: insights from biological data and computational approaches

Background

Disulfiram (DSF) is an anti-alcoholic drug that has been reported to inhibit the epithelial-to-mesenchymal transition and crosslinking during fibrosis, pyroptosis, and inflammatory NF-κB and Nrf-2 signaling pathways. However, there is insufficient evidence to support the mechanisms of DSF in preventing renal fibrosis (RF). Therefore, the current study aimed to elucidate the DSF-modulated targets and pathways in renal fibrosis.

Methods

The common proteins between DSF and RF were screened for protein-protein interaction, pathway enrichment, cluster, and gene ontology analysis. Molecular docking was executed for core genes using AutoDock Vina through the POAP pipeline. Molecular dynamics (MD) simulation (100 ns) was performed to infer protein-ligand stability, and conformational changes were analyzed by free energy landscape (FEL).

Results

A total of 78 targets were found to be common between DSF and RF, of which NFKB, PIK3CA/R1, MTOR, PTGS2, and MMP9 were the core genes. PI3K-Akt signaling followed by JAK-STAT, TNF, Ras, ErbB, p53, phospholipase D, mTOR, IL-17, NF-κB, AMPK, VEGF, and MAPK signaling pathways were modulated by DSF in RF. DSF showed a direct binding affinity with active site residues of core genes, and except for DSF with NF-κB, all other complexes, including the standard, were found to be stable during 100 ns MD simulation with minimal protein-ligand root mean squared deviation and residual fluctuations and higher compactness with broad conformational changes.

Conclusion

DSF protects against renal fibrosis, and this study paves the way for experimental investigation to repurpose DSF for treating RF.

Benefits of aldosterone receptor antagonism in chronic kidney disease: the BARACK-D RCT

Background

Chronic kidney disease affects around 10% of the global population and is associated with significant risk of progression to end-stage renal disease and vascular events. Aldosterone receptor antagonists such as spironolactone have shown prognostic benefits in patients with heart failure, but effects on patients with chronic kidney disease are uncertain.

Objectives

To determine the effect of low-dose spironolactone on mortality and cardiovascular outcomes in people with chronic kidney disease stage 3b.

Design

Prospective randomised open blinded end-point trial.

Settings

Three hundred and twenty-nine general practitioner practices throughout the United Kingdom.

Participants

Patients meeting the criteria for chronic kidney disease stage 3b (estimated glomerular filtration rate 30-44 ml/minute/1.73 m2) according to National Institute for Health and Care Excellence guidelines were recruited. Due to the higher than anticipated measurement error/fluctuations, the eligible range was extended to 30-50 ml/minute/1.73 m2 following the initial recruitment period.

Intervention

Participants were randomised 1 : 1 to receive either spironolactone 25 mg once daily in addition to standard care, or standard care only.

Outcome measures

Primary outcome was the first occurring of all-cause mortality, first hospitalisation for heart disease (coronary heart disease, arrhythmia, atrial fibrillation, sudden death, failed sudden death), stroke, heart failure, transient ischaemic attack or peripheral arterial disease, or first occurrence of any condition not listed at baseline. Secondary outcome measures included changes in blood pressure, renal function, B-type natriuretic peptide, incidence of hyperkalaemia and treatment costs and benefits.

Results

One thousand four hundred and thirty-four participants were randomised of the 3022 planned. We found no evidence of differences between the intervention and control groups in terms of effectiveness with the primary combined vascular end points, nor with the secondary clinical outcomes, including progression in renal decline. These results were similar for the total treatment periods or a 3-year follow-up period as originally planned. More adverse events were experienced and more participants discontinued treatment in the intervention group. Two-thirds of participants randomised to spironolactone stopped treatment within six months because they met pre-specified safety stop criteria. The addition of low-dose spironolactone was estimated to have a cost per quality-adjusted life-year gained value above the National Institute for Health and Care Excellence's threshold of £30,000.

Limitations

Main limitations were difficulties in recruiting eligible participants resulting in an underpowered trial with poor ethnic diversity taking twice as long as planned to complete. We have explored the data in secondary analyses that indicate that, despite these difficulties, the findings were reliable.

Conclusions

The benefits of aldosterone receptor antagonism in chronic kidney disease trial found no evidence to support adding low-dose spironolactone (25 mg daily) in patients with chronic kidney disease stage 3b: there were no changes to cardiovascular events during the trial follow-up, either for the combined primary or individual components. There was also no evidence of benefit observed in rates of renal function decline over the trial, but much higher initial creatinine rise and estimated glomerular filtration rate decline, and to a higher percentage rate, in the intervention arm in the first few weeks of spironolactone treatment, which resulted in a high proportion of participants discontinuing spironolactone treatment at an early stage. These higher rates of negative renal change reduced in scale over the study but did not equalise between arms. The addition of 25 mg of spironolactone therefore provided no reno- or cardio-protection and was associated with an increase in adverse events.

Future work

These findings might not be applicable to different mineralocorticoid receptor antagonists.

Study registration

Current Controlled Trials ISRCTN44522369.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 12/01/52) and is published in full in Health Technology Assessment; Vol. 29, No. 5. See the NIHR Funding and Awards website for further award information.

Effect of β-catenin on hypoxia induced epithelial mesenchymal transition in HK-2 cells by regulating Brachyury

Background

Chronic kidney disease (CKD) has become a worldwide health problem and the incidence rate and mortality of CKD have been rising. Renal fibrosis (RF) is the final common pathological feature of almost all kinds of CKD and Epithelial-mesenchymal transition (EMT) is the predominant stage of RF. β-catenin is a key component of the Wnt signaling pathway, which has been fully proven to promote EMT. However, the underlying mechanism of β-catenin in EMT during the pathogenesis of RF is yet to be determined.

Objective

This study was designed to investigate the effects of β-catenin on RF-related EMT and further investigate its underlying mechanism.

Methods

Human proximal tubular epithelial cell (HK-2) was treated with hypoxia to construct RF injury cell model. The viability of cells was determined by CCK-8 assay. Immunofluorescence was used to detect α-SMA content. Expressions of β-catenin, Brachyury and RF-related proteins were measured by Western blot. The correlation between β-catenin and Brachyury was detected by ChIP-qPCR and dual luciferase reporter assay.

Results

We found β-catenin was overexpressed in hypoxia-induced HK-2 cells. In the RF cell model, silencing of β-catenin weakened the EMT and fibrogenesis activity of HK-2 cells. Mechanistically, we found β-catenin binds to T-cell factor (TCF) to activate Brachyury, which is a positive player in EMT. Further studies clarified that Brachyury was responsible for β-catenin-promoted the EMT and HK-2 cell injury under hypoxia condition.

Conclusions

Herein, we demonstrated that β-catenin is overexpressed in hypoxia-induced HK-2 cells and promotes EMT and cell injury via activating Brachyury. These findings suggest that targeting β-catenin/Brachyury may be an effective new approach for treating RF.

Plumbagin ameliorates renal fibrosis by suppressing epithelial-mesenchymal transition

Renal fibrosis is a common pathological feature of chronic kidney diseases (CKDs), driven by excessive extracellular matrix (ECM) accumulation. Despite its prevalence, therapeutic candidates specifically targeting fibrosis are limited, and the role of renal tubular epithelial cells in fibrosis pathogenesis remains unclear. In this study, we evaluated the anti-fibrotic effects of Plumbagin, a plant-derived natural compound, using a folic acid-induced renal fibrosis model that simulates proximal tubular injury-driven fibrosis. Plumbagin treatment significantly attenuated renal fibrosis in a folic acid-induced model. Furthermore, using the human proximal tubular epithelial cell line HK-2, we assessed EMT, a key fibrosis-promoting biological process, and the expression of fibrosis-related factors. Plumbagin treatment reduced TGF-β-induced EMT and fibrosis-related factor expression in HK-2 cells. In summary, Plumbagin suppresses EMT in renal tubular epithelial cells under fibrotic conditions and alleviates renal fibrosis. These findings highlight the potential of Plumbagin as a therapeutic drug for renal fibrosis and propose a shared therapeutic strategy for CKD patients.

Methylglyoxal Formation-Metabolic Routes and Consequences

Methylglyoxal (MGO), a by-product of glycolysis, plays a significant role in cellular metabolism, particularly under stress conditions. However, MGO is a potent glycotoxin, and its accumulation has been linked to the development of several pathological conditions due to oxidative stress, including diabetes mellitus and neurodegenerative diseases. This paper focuses on the biochemical mechanisms by which MGO contributes to oxidative stress, particularly through the formation of advanced glycation end products (AGEs), its interactions with antioxidant systems, and its involvement in chronic diseases like diabetes, neurodegeneration, and cardiovascular disorders. MGO exerts its effects through multiple signaling pathways, including NF-κB, MAPK, and Nrf2, which induce oxidative stress. Additionally, MGO triggers apoptosis primarily via intrinsic and extrinsic pathways, while endoplasmic reticulum (ER) stress is mediated through PERK-eIF2α and IRE1-JNK signaling. Moreover, the activation of inflammatory pathways, particularly through RAGE and NF-κB, plays a crucial role in the pathogenesis of these conditions. This study points out the connection between oxidative and carbonyl stress due to increased MGO formation, and it should be an incentive to search for a marker that could have prognostic significance or could be a targeted therapeutic intervention in various diseases.

Exploring the therapeutic potential of leriodenine and nuciferine from Nelumbo nucifera for renal fibrosis: an In-silico analysis

A major problem in chronic kidney illnesses is renal fibrosis. This research investigates the therapeutic potential of compounds derived from Nelumbo nucifera (Lotus). Comprehensive screening identified these compounds, which exhibit promising binding affinities with key targets associated with renal fibrosis. Leriodenine and Nuciferine demonstrate substantial potential by modulating critical targets such as PTGS2, JUN, EGFR, STAT3, mTOR, and AKT1. The identified biomolecule-target-pathway network highlights the intricate interactions underlying the therapeutic effects of lotus seed compounds in renal fibrosis. Strong binding affinities with PTGS2-PDBID:5F19, Leriodenine -8.99 kcal/mol and Nuciferine -9.33 kcal/mol, and JUN-PDBID:1S9K, Leriodenine -7.95 kcal/mol and Nuciferine -7.05 kcal/mol are shown by molecular docking investigations, indicating their potential as fibrotic process inhibitors. During 10 ns of molecular docking simulations, these compounds demonstrated robust hydrogen-bonding connections within the protein's active site, leading to a possible alteration in the conformation of the ligand-binding site. The research establishes the foundation for future experimental validation, clinical trials, to bridge the translational gap. The research combines target prediction, protein-protein interaction studies, and biomolecular screening to clarify the molecular pathways behind renal fibrosis. We also carried out Insilico molecular docking and carried out molecular dynamics simulation of the best compound identified to obtain more precise results.

Yiqi Juanshen decoction alleviates renal interstitial fibrosis by targeting the LOXL2/PI3K/AKT pathway to suppress EMT and inflammation

Chronic kidney disease (CKD) is a major health concern, with renal interstitial fibrosis (RIF) as a key feature. Effective management of RIF is crucial for treating CKD. Yiqi Juanshen decoction (YQJSD), as traditional Chinese medicine, has shown promising results in CKD treatment. This study evaluates YQJSD's effectiveness in ameliorating RIF and explores the underlying molecular mechanisms using the unilateral ureteral obstruction (UUO) model. YQJSD has been shown to effectively reduce serum creatinine and blood urea nitrogen levels, decrease extracellular matrix deposition, and down-regulate the expression of α-SMA, COL4α1, Fibronectin (FN). Mechanistically, YQJSD exerts its effects by modulating multiple pathways: it inhibits the NF-κB signaling pathway, inhibiting the expression of pro-inflammatory cytokines like NF-κB1, IL-1β, TNF-α, and CCR1. Simultaneously, YQJSD suppresses the epithelial-mesenchymal transition (EMT) by downregulating the expression of Snail1, Vimentin, Twist1, and FSP1, while increasing E-cadherin expression. Moreover, YQJSD can regulate the PI3K/AKT signaling pathway by decreasing the expression of LOXL2 and PIK3R1, along with p-AKT1/2/3. This modulation of the LOXL2/PI3K/AKT pathway contributes to the inhibition of both EMT and inflammation, highlighting a critical role in the therapeutic intervention against RIF. These findings suggest that YQJSD may serve as a promising therapeutic management of RIF in CKD patients.

Donkey milk supplementation alleviates renal fibrosis of chronic kidney disease by enhancing anti-inflammatory ability

Donkey milk, rich in essential nutrients, is not only able to meet the nutritional needs of patients with chronic kidney disease (CKD) according to the National Kidney Foundation's Kidney Disease Outcomes Quality Initiative Clinical Practice Guideline for Nutrition in CKD, but also has strong anti-inflammatory properties. Inflammation is the main driving force of renal fibrosis, which directly determines renal function in CKD. However, the impact of donkey milk on CKD and the underlying mechanisms remain unclear. We hypothesized that donkey milk supplementation could enhance anti-inflammatory abilities in individuals with CKD, thereby inhibiting renal fibrosis and improving renal function. Therefore, we investigated the influence of a 6-wk treatment with donkey milk on unilateral ureteral ligation-induced CKD rats. The results demonstrated that the level of miR-223-3p was decreased in the kidneys of CKD rats compared with normal rats. However, donkey milk supplementation activated miR-223-3p, thereby inhibiting the expression of inhibitor of kappa-B kinase (IKKα) and nuclear factor kappa-B (NF-κB) proteins. Consequently, the expression of inflammatory factors such as monocyte chemotactic protein-1 (MCP-1) and IL-6 was suppressed, leading to reduced aggregations of macrophages in the kidney and decreased transforming growth factor β1 (TGF-β1) expression. Ultimately, renal fibrosis was inhibited, which was confirmed by decreased collagen type I α 1 (COL1A1) mRNA, thereby the renal function of CKD rats was improved. These results indicate that miR-223-3p may be another potential therapeutic target for CKD. Moreover, the contribution of donkey milk to alleviating the inflammatory response and renal fibrosis of CKD is obvious, indicating that donkey milk may be a new functional food for CKD patients to promote health.

Unveiling the substantial role of rutin in the management of drug-induced nephropathy using network pharmacology and molecular docking

INTRODUCTION

Flavonoids including quercetin, kaempferol, myricetin, rutin etc. have always been a part of traditional Chinese medicine for the treatment of several ailments. Rutin (RT), also known as rutoside, sophorin is one of the flavanol glycoside having structure resemblance with quercetin. It is found to exhibit several biological activities viz. anti-inflammatory, anticancer, antioxidant, cardioprotective, antidepressant, neuroprotective etc. but the mechanisms by which it exhibits these effects is still under research.

AIM

The protective effects of rutin against drug induced nephropathy have already been discovered. Therefore, in this study, the main focus is to explore the mechanism by which rutin provides protection against drug-induced nephropathy using modern method like network pharmacology and molecular docking.

MATERIALS AND METHODS

Genes linked to drug-induced nephropathy and targets connected with rutin were obtained by searching through a number of extensive databases, including David software, Venn plot database, Swiss target prediction database, String database, Gene card & OMIM database, and Pubchem. In order to locate mapping targets, the acquired targets were examined and intersected. A protein-protein interaction (PPI) network was then built to find potential targets.

RESULTS

From the KEGG pathway, the target pathway responsible for drug-induced nephropathy were found to be XDH, HSD17B2, MET, PRKCB, CD38, ALDH2, CDK1, PTK2, CYP19A1, TNF, F2, PTGS2, ESR1, GSK3B, GLO1, ALOX12, MMP3, PRKCZ, CXCR1, CA4, EGFR, PDE5A, F10, AKR1B1, DRD4, TERT, CA3, PLG, TP53, PRKCH, PIK3R1, PRKACA, CYP1B1, ALOX5, PLK1, CHEK1, KCNH2, PRKCD, MAPT, MPO, NOX4, AVPR2, ACHE, MCL1, KDR, ABCG2, CCR1, PIK3CG, FLT3, ADORA1, IL2, SYK, IGF1R, CA2, SERPINE1, INSR, PRKCA, APP, MMP9. From these identified targets, the 14 selected pathways which have major role in providing protection in drug-induced nephropathy have been discussed.

CONCLUSION

As RT can inhibit various metabolic and proinflammatory pathways involved, it can help in prevention and treatment of drug-induced nephropathy.

FUTURE ASPECTS

The revelation of mode of action of bioactive constituent rutin against drug-induced nephropathy provides a theoretical basis for designing more promising compounds in future for treatment of nephropathy.

The application of mind mapping in the standardized education of inpatient physicians in nephrology

This study aims to investigate the effectiveness of mind mapping in the standardized training and education of internal medicine resident physicians in nephrology. Sixty trainees undergoing rotations in the Nephrology Department at Chengdu University Affiliated Hospital between January 2021 and December 2023 were randomly assigned to control and observation groups, each comprising 30 trainees. The observation group received mind mapping teaching, while the control group received traditional teaching methods. The clinical thinking training of the two groups was then compared. The observation group outperformed the control group in all aspects of the Mini-CEX assessment, including medical interviews, humanistic care, clinical judgment, communication skills, overall performance, and total score, with statistical significance (P < 0.05). However, there were no statistically significant differences between the two groups in the areas of physical examination and organizational effectiveness (P > 0.05). Furthermore, the observation group achieved higher scores than the control group in the final theory exam, skill exam results, and satisfaction, with statistically significant differences (P < 0.05). Mind mapping not only aids in the consolidation of fundamental memorized knowledge but also enhances clinical thinking skills, thereby playing a pivotal role in assisting resident physicians in establishing a comprehensive knowledge base in nephrology and improving the effectiveness of their training.

Weekly administration of betulinic acid prevents development of chronic renal failure from acute renal failure in folic acid-induced mouse model of kidney injury

Betulinic acid (BA) has been shown to exhibit various pharmacological activities and it has shown the protective effect on acute renal failure (ARF) and chronic renal failure (CRF); however, no reports are available on its effect on ARF-CRF transition. Therefore, we aimed to investigate the effects of BA on ARF-CRF transition. A single dose of 250 mg/kg body weight (BW) intraperitoneal injection of folic acid was given in mice for inducing ARF-CRF transition (injury group; I) on day 1. Further, excess of these mice received BA at 30 mg/kg BW dose for 3 days (on days 1, 2, 3) in one group (IT3) and for 7 days (on days 1, 2, 3, 7, 14, 21, 28) in another group (IT7). All mice were sacrificed on day 28. Mice in injury group (I) showed elevated serum creatinine along with oxidative stress markers like urine nitrite, tissue lipid peroxidation, nitrotyrosine and fibrotic markers such as tissue α-smooth muscle actin and matrix metalloproteinase-2 activity. They had attenuated levels of urine creatinine and tissue reparative cytokines viz. interleukin-4 and interleukin-13. Excess of fibroblasts and extracellular matrix in the interstitia and periglomerular area in microscopy further support these findings. Seven days of BA treatment regimen (IT7) significantly improved serum and urine parameters accompanied by reduced oxidative stress, improved reparative cytokines and lesser maladaptive matrix deposition. The above findings reveal that weekly BA treatment regimen has potential to prevent development of CRF after ARF.

End-to-End CT Radiomics-Based Pipeline for Predicting Renal Interstitial Fibrosis Grade in CKD Patients

RATIONALE AND OBJECTIVES

Non-invasive assessment of renal fibrosis in patients with chronic kidney disease (CKD) remains a clinical challenge. This study aims to integrate radiomics and clinical factors to develop an end-to-end pipeline for predicting interstitial fibrosis (IF) in CKD patients.

MATERIALS AND METHODS

This retrospective study included 80 patients with CKD, with 53 patients in training set and 27 patients in test set. All patients underwent renal computed tomography (CT) scans and biopsy. Patients were classified into two groups based on their renal IF grade: mild-moderate and severe. Radiomics features were extracted from the automatically segmented right renal region on CT images, and univariate analysis along with multiple Least Absolute Shrinkage and Selection Operator (LASSO) was employed to construct the radiomics signature. Subsequently, logistic regression models were developed to create the radiomics model and the combined model. The predictive performance of both models was evaluated through discrimination, calibration, and decision curve analysis (DCA), and a nomogram was constructed for the model demonstrating superior performance.

RESULTS

The combined model significantly outperformed the radiomics model, achieving a cross-validated AUC of 0.935±0.041 in the training set, compared to 0.804±0.024 for the radiomics model. In the test set, the combined model outperformed the radiomics model, with an AUC of 0.918 [95% CI 0.799-1] vs. 0.764 [95% CI 0.549-0.979], p=0.031 (DeLong test, Statistic: -2.152). Calibration curves and DCA indicated that the combined model demonstrated good calibration and better clinical net benefit.

CONCLUSION

This end-to-end workflow could serve as a potential non-invasive tool to predict renal IF grade (mild-moderate vs. severe) in CKD patients.

LncRNA TUG1 mitigates chronic kidney disease through miR-542-3p/HIF-1α/VEGF axis

Renal interstitial fibrosis (RIF) is a common pathway in chronic kidney disease (CKD) that ultimately leads to end-stage renal failure, worsening both glomerulosclerosis and interstitial fibrosis. Ten percent of the adult population in the world suffers from CKD, and as the ageing population continues to rise, it is increasingly regarded as a global threat-a silent epidemic. CKD has been discovered to be closely associated with both long noncoding RNAs (lncRNAs) and microRNAs (miRNAs), while the precise molecular processes behind this relationship are still unclear. This study evaluated the impact of miR-542-3p and lncRNA TUG1 on renal fibrosis, along with the underlying regulatory mechanisms. Through in vitro tube formation assays, research demonstrated that knocking down lncRNA TUG1 may enhance angiogenesis and repair damaged endothelial cell-cell connections. We used Western blot and qRT-PCR methods in the unilateral ureteral obstruction (UUO) model to identify tissue hypoxia and fibrotic lesions. Additionally, a cutting-edge method known as fluorescence microangiography (FMA) was employed to detect damage to the peritubular capillaries (PTCs), with MATLAB software utilised for data evaluation. Furthermore, the coexpression of CD31 and α-SMA helped identify cells in the obstructed kidney that were transitioning from endothelium to myofibroblasts. On the contrary, lncRNA TUG1 downregulation showed a protective effect against the transition from endothelial cells to myofibroblasts. Additionally, knocking down lncRNA TUG1 has been shown to reduce the expression of fibrotic markers by alleviating tissue hypoxia. This effect was significantly counteracted by the inhibition of miR-542-3p. Collectively, our findings offer fresh perspectives on how lncRNA TUG1 and the miR-542-3p/HIF-1α/VEGF axis are regulated as renal fibrosis advances.

Lipidomics-based natural products for chronic kidney disease treatment

Chronic kidney disease (CKD) is by far the most prevalent disease in the world and is now a major global public health problem because of the increase in diabetes, hypertension and obesity. Traditional biomarkers of kidney function lack sensitivity and specificity for early detection and monitoring of CKD progression, necessitating more sensitive biomarkers for early diagnostic intervention. Dyslipidemia is a hallmark of CKD. Advancements in mass spectrometry (MS)-based lipidomics platforms have facilitated comprehensive analysis of lipids in biological samples and have revealed changes in the lipidome that are associated with metabolic disorders, which can be used as new biomarkers for kidney diseases. It is also critical for the discovery of new therapeutic targets and drugs. In this article, we focus on lipids in CKD, lipidomics methodologies and their applications in CKD. Additionally, we introduce novel biomarkers identified through lipidomics approaches and natural products derived from lipidomics for the treatment of CKD. We believe that our study makes a significant contribution to literature by demonstrating that natural products can improve CKD from a lipidomic perspective.

Current status and prospects of traditional Chinese medicine combined with stem cell therapy for chronic kidney disease

Renal fibrosis is one of the main pathological features of chronic kidney disease (CKD), and its treatment has been a hot research topic. Recent studies have shown that stem cell therapy can repair renal pathological changes and slow the progression of CKD. In addition, a large number of experiments have confirmed that traditional Chinese medicine (TCM), especially Chinese medicine compound preparations, has the advantage of multitargeting interventions to improve renal fibrosis. Therefore, stem cell therapy combined with TCM is expected to provide new therapeutic ideas and measures to solve kidney problems. This article reviews the current status of TCM combined with stem cell therapy for CKD, discusses existing problems, and proposes future prospects.

Increased NPM1 inhibit ferroptosis and aggravate renal fibrosis via Nrf2 pathway in chronic kidney disease

Recent findings underscore the significance of ferroptosis, an innovative iron-dependent mode of cell death, in the etiology and progression of chronic kidney disease (CKD). Nucleophosmin 1 (NPM1), a nucleolar protein, contributes to fibrogenesis and modulates cellular functions and mortality. Initial investigations utilized bioinformatics techniques to pinpoint genes with altered expression in CKD and to forecast the potential links between NPM1, ferroptosis, and renal fibrosis. Increased NPM1 expression was verified in the renal tissues of CKD patients. Experimental models of renal fibrosis in both animals and cells were then used for further study. The suppression of NPM1 led to an augmentation in iron metabolism and lipid peroxidation processes integral to ferroptosis, contributing to the mitigation of renal fibrosis. In contrast, an elevation in NPM1 expression had the opposite effect. This modulation may be interconnected with the nuclear factor erythroid 2-related factor 2 pathway. Moreover, the application of the ferroptosis inhibitor, Fer-1, not only obstructed ferroptosis but also diminished NPM1 expression, which, in turn, contributed to the alleviation of renal fibrosis. Thus, our findings suggest that in CKD the NPM1 level increased and led to decreased ferroptosis and aggravated renal fibrosis via an Nrf2 pathway. Ferroptosis inhibitor can alleviate renal fibrosis.

Novel drug delivery systems for hirudin-based product development and clinical applications

Hirudin, a natural biological polypeptide macromolecule secreted by the salivary glands of medicinal leech, is a specific thrombin inhibitor with multiple favourable bioactivities, including anti-coagulation, anti-fibrotic, and anti-tumour. Despite several anticoagulants have been widely applied in clinic, hirudin shows advantages in reducing the incidence of bleeding side effects by virtue of its high specificity in binding to thrombin. As a result, hirudin has been tested in clinical practice to prevent and treat several complex diseases. However, the application of this polypeptide macromolecule is compromised by its low bioavailability and bioactivity due to poor serum stability and susceptibility to protease degradation in vivo. To overcome these drawbacks, several studies have proposed novel drug delivery systems (NDDSs) to prevent the degradation and increase the targeting efficiency of hirudin. This systematic review summarises the clinical research on hirudin, including its classification and bioactivities, and highlights the opportunities and challenges in the clinical use of hirudin. The NDDSs designed to enhance the bioavailability and bioactivity of hirudin are discussed to explore its application in the treatment of related diseases. This review may considerably contribute to the advancement of delivery science and technology, particularly in the context of polypeptide-based therapeutics.

Repurposing Nano Curcumin: Unveiling its Therapeutic Potential in Diabetic Nephropathy

Currently, Diabetic Nephropathy (DN) stands as the predominant global cause of endstage renal disease. Many scientists believe that diabetes will eventually spread to pandemic levels due to the rising prevalence of the disease. While the primary factor leading to diabetic nephropathy is vascular dysfunction induced by hyperglycemia, several other pathological elements, such as fibrosis, inflammation, and oxidative stress, also contribute to the progression of the disease. The primary targets of current DN therapy approaches are the underlying abnormalities of hypertension and glucose. With several targets and fewer side effects, curcumin is a commonly utilized antioxidant in DN. The present study emphasizes the critical role of oxidative stress and inflammation in the development of diabetic nephropathy. It reveals how these factors induce damage in key kidney cell types, highlighting their potential as therapeutic targets for this disease. In addition, by concentrating on Nrf2, SIRT1, HMGB1, NF-κB, and NLRP3 of curcumin, has strong anti- inflammatory and antioxidant characteristics. This review describes the role of curcumin in the therapeutic application of diabetic nephropathy. In this attempt, we tried to elaborate on the bench-to-bedside aspects of curcumin in DN, including clinical and preclinical investigations. The rationales of curcumin's mechanisms in alleviating symptoms of the DN were discussed. Curcumin could serve as the potential therapeutic agent for the patient seeking to recover from DN.

Deubiquitinase inhibitor bAP-15 suppresses renal epithelial to mesenchymal transition via inhibition of p300 stability

Renal fibrosis is an irreversible disease that is common in patients with chronic kidney disease. Elevated levels of the histone acetyltransferase p300 have been reported in various fibrotic diseases, including renal fibrosis, suggesting that p300 may be a promising therapeutic target. To investigate the specific deubiquitinase (DUB) involved in the regulation of p300 protein stability in renal epithelial cells, we tested 13 DUB inhibitors using a kidney tubular epithelial cell line. We found that the p300-specific DUB inhibitor, bAP-15 reduces p300 protein stability by targeting ubiquitin-specific protease 14 (USP14) and ubiquitin C-terminal hydrolase L5 (UCHL5). The mRNA levels of USP14 and UCHL5 were increased in patients with chronic kidney disease, and increased protein levels of USP14 and UCHL5 during fibrosis progression were validated using a mouse renal fibrosis model. Both USP14 and UCHL5 interacted with p300 in kidney tubular epithelial cells, with increased binding affinity in response to TGF-β. Moreover, bAP-15-induced p300 degradation inhibited epithelial-to-mesenchymal transition and reduced the expression of pro-fibrotic target genes. Our findings demonstrate an anti-fibrotic effect of bAP-15 through the regulation of p300 stability and suggest that bAP-15 may be a potential therapeutic agent for renal fibrosis.

Decoding Kidney Pathophysiology: Omics-Driven Approaches in Precision Medicine

Chronic kidney disease (CKD) is a major worldwide health concern because of its progressive nature and complex biology. Traditional diagnostic and therapeutic approaches usually fail to account for disease heterogeneity, resulting in low efficacy. Precision medicine offers a novel approach to studying kidney disease by combining omics technologies such as genomics, transcriptomics, proteomics, metabolomics, and epigenomics. By identifying discrete disease subtypes, molecular biomarkers, and therapeutic targets, these technologies pave the way for personalized treatment approaches. Multi-omics integration has enhanced our understanding of CKD by revealing intricate molecular linkages and pathways that contribute to treatment resistance and disease progression. While pharmacogenomics offers insights into expected responses to personalized treatments, single-cell and spatial transcriptomics can be utilized to investigate biological heterogeneity. Despite significant development, challenges persist, including data integration concerns, high costs, and ethical quandaries. Standardized data protocols, collaborative data-sharing frameworks, and advanced computational tools such as machine learning and causal inference models are required to address these challenges. With the advancement of omics technology, nephrology may benefit from improved diagnostic accuracy, risk assessment, and personalized care. By overcoming these barriers, precision medicine has the potential to develop novel techniques for improving patient outcomes in kidney disease treatment.

Apocynin and Hyperbaric Oxygen Therapy Improve Renal Function and Structure in an Animal Model of CKD

BACKGROUND/OBJECTIVES

Chronic kidney disease (CKD) is a progressive pathological condition which results in the severe fibrosis of the kidneys. However, the mechanisms of CKD progression and fibrogenesis remain unclear. We wanted to examine the effects that apocynin and hyperbaric oxygen therapy (HBOT) have on renal function and structure in animals with CKD induced through 5/6 nephrectomy (5/6 Nx-L).

METHODS

Male Wistar rats were divided in 5 groups (n = 8/group) as follows: control-sham-operated rats; Nx-L-rats with 5/6 Nx-L; APO-5/6 Nx-L + apocynin treatment; HBOT-5/6 Nx-L + hyperbaric oxygen treatment, and APO+HBOT-5/6 Nx-L, treated with both treatments. All treatments started 4 weeks after the final step of CKD induction and lasted for 4 weeks. At the end of the experiment, urine samples were collected for the proteinuria assessment and the mean arterial pressure (MAP) was measured. Kidneys were collected for histopathological, Western blot, and immunohistochemical analyses.

RESULTS

All treatments significantly decreased MAP compared to the Nx-L group (p < 0.001). In the APO and APO+HBOT groups, the level of proteinuria was decreased compared to the Nx-L group (p < 0.05 and p < 0.01, respectively). All examined treatments significantly decreased the intensity of lesions in the kidney compared to those observed in the Nx-L group (p < 0.001). Isolated treatments with apocynin and HBOT induced a significant decrease in desmin expression compared to the Nx-L group (p < 0.05); meanwhile, they did not affect the levels of fibronectin (FN) and hypoxia-inducible factor-1α (HIF-1α). Combined treatment did not affect desmin expression levels; however, it induced a significant increase in fibronectin expression compared to Nx-L (p < 0.001).

CONCLUSIONS

Apocynin treatment decreased BP and protein loss, and it improved renal morphology at least partly through the downregulation of desmin expression without changing FN and HIF-1α. Hyperbaric oxygen therapy improved hypertension but failed to significantly affect the level of proteinuria. Combined treatment (apocynin and HBOT) normalized blood pressure (BP) values, renal function, and improved kidney structure by modulating FN and HIF-1α, without affecting desmin protein expression. Further studies are needed to elucidate the mechanisms of slowing down the progression of CKD in this experimental model.

Chlorogenic acid alleviate kidney fibrosis through regulating TLR4/NF-қB mediated oxidative stress and inflammation

ETHNOPHARMACOLOGICAL RELEVANCE

Chlorogenic acid (CGA), a phenolic acid produced by the interaction of Caffeic acid and Quinic acid, is considered to be the main active ingredient in many heat-clearing and detoxifying Chinese medicines, such as honeysuckle, Houttuynia, Artemisia annua, Gardenia, etc. CGA has anti-inflammatory, antioxidant, anticancer, antibacterial and other properties. However, the effect and process of CGA in kidney fibrosis remain unknown.

AIM OF THE STUDY

To investigate the therapeutic effects of CGA on alleviating kidney fibrosis and the underlying mechanisms.

MATERIALS AND METHODS

C57BL/6 mouse kidney fibrosis model was established by unilateral uretera obstruction (UUO), followed by treatment with CGA (40, 80 mg/kg/d) for 10 days. The serum and kidney tissue were collected. Network pharmacology, molecular docking and transcriptomic analysis were conducted to explore the possible mechanisms. The HK-2 cells were cultured and treated with TGF-β1(10 ng/mL) and CGA (50, 100 μM), to examine the role of TLR4/NF-қB signaling pathway in the therapeutic effect of CGA on kidney fibrosis.

RESULTS

CGA significantly alleviated kidney injury, inflammation, oxidative stress and fibrosis in UUO models. CGA also effectively inhibited the expression of inflammatory factors and the process of oxidative stress both in vivo and in vitro fibrosis models. Further, transcriptomic analysis, molecular docking, and network pharmacology results indicated that the therapeutic effect of CGA on fibrosis was through the regulation of TLR4/NF-қB signaling pathway.

CONCLUSION

CGA might provide benefits for the regulation of inflammatory response, oxidative stress and fibrogenesis by modulating TLR4/NF-қB signaling pathway on kidney fibrosis. Hence, CGA is an attractive agent for treating kidney fibrosis. The present study provided a basis for further research on the therapeutic strategies of kidney fibrosis.

Imperatorin ameliorates ferroptotic cell death, inflammation, and renal fibrosis in a unilateral ureteral obstruction mouse model

BACKGROUND

Imperatorin is a naturally occurring furocoumarin derivative found in traditional Chinese medicine Angelica dahurica for its anticancer, antihypertensive, and antidiabetic properties. Chronic kidney disease (CKD) is a global health issue, characterized by a high prevalence, significant morbidity and mortality, and a range of related complications.

OBJECTIVE

This study aims to investigate the protective effects of imperatorin treatment and the specific underlying mechanisms in progressive CKD.

METHODS

Imperatorin was orally administrated for 14 consecutive days to mice with unilateral ureteral obstruction (UUO) to investigate the renal pathological alternations, pro-inflammatory mediators, antioxidant response, and ferroptotic death signaling. Imperatorin was also tested in the erastin-induced injury of renal proximal tubular cells (NRK-52E). Cell viability, ferroptosis protein markers, erastin-induced oxidative stress, and lipid peroxidation were assessed.

RESULTS

In vivo, imperatorin treatment alleviated kidney histology alternations and attenuated the protein expression of fibrotic markers. Furthermore, imperatorin administration reduced inflammatory cell infiltration, and alleviated the oxidative stress burden by downregulating protein markers such as catalase, superoxide dismutase 2 (SOD-2), NADPH oxidase 4 (NOX-4), and thioredoxin reductase 1 (Trxr-1). It also mitigated ferroptosis markers such as glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11/cystine transporter (SLC7A11/xCT), and transferrin receptor 1 (TFR-1), and attenuated renal cell apoptosis. In vitro, imperatorin treatment effectively decreased erastin-induced feroptotic cell death, restored the antioxidant enzyme levels, and mitigated lipid peroxidation as well as the expression of ferroptosis-related markers (XCT, GPX4, and p-p53) in a dose-dependent manner.

CONCLUSION

Our finding demonstrated for the first time, that imperatorin treatment holds therapeutic potential in a UUO mouse model of CKD and inhibits the erastin-induced oxidative stress, ferroptosis, and subsequent lipid peroxidation in vitro. This highlights the potential of imperatorin as a future therapeutic target for ferroptosis to improve the progression of CKD.

Adenine-induced animal model of chronic kidney disease: current applications and future perspectives

Chronic kidney disease (CKD) with high morbidity and mortality all over the world is characterized by decreased kidney function, a condition which can result from numerous risk factors, including diabetes, hypertension and obesity. Despite significant advances in our understanding of the pathogenesis of CKD, there are still no treatments that can effectively combat CKD, which underscores the urgent need for further study into the pathological mechanisms underlying this condition. In this regard, animal models of CKD are indispensable. This article reviews a widely used animal model of CKD, which is induced by adenine. While a physiologic dose of adenine is beneficial in terms of biological activity, a high dose of adenine is known to induce renal disease in the organism. Following a brief description of the procedure for disease induction by adenine, major mechanisms of adenine-induced CKD are then reviewed, including inflammation, oxidative stress, programmed cell death, metabolic disorders, and fibrillation. Finally, the application and future perspective of this adenine-induced CKD model as a platform for testing the efficacy of a variety of therapeutic approaches is also discussed. Given the simplicity and reproducibility of this animal model, it remains a valuable tool for studying the pathological mechanisms of CKD and identifying therapeutic targets to fight CKD.

Identification of common and specific fibrosis-related genes in three common chronic kidney diseases

BACKGROUND

Kidney fibrosis is the common final pathway of virtually all advanced forms of chronic kidney disease (CKD) including diabetic nephropathy (DN), IgA nephropathy (IgAN) and membranous nephropathy (MN), with complex mechanism. Comparative gene expression analysis among these types of CKD may shed light on its pathogenesis. Therefore, we conducted this study aiming at exploring the common and specific fibrosis-related genes involved in different types of CKD.

METHODS

Kidney biopsy specimens from patients with different types of CKD and normal control subjects were analyzed using the NanoString nCounter® Human Fibrosis V2 Panel. Genes differentially expressed in all fibrotic DN, IgAN and MN tissues compared to the normal controls were regarded as the common fibrosis-related genes in CKD, whereas genes exclusively differentially expressed in fibrotic DN, IgAN or MN samples were considered to be the specific genes related to fibrosis in DN, IgAN and MN respectively. Quantitative real-time PCR (qRT-PCR) was performed to validate the expression of the selected genes.

RESULTS

Protein tyrosine phosphatase receptor type C (PTPRC), intercellular cell adhesion molecule-1 (ICAM1), vascular cell adhesion molecule-1 (VCAM1), interleukin 10 receptor alpha (IL10RA) and CC chemokine receptor 2 (CCR2) were identified as the potential common genes for kidney fibrosis in different types of CKD, while peroxisome proliferator-activated receptor alpha (PPARA), lactate oxidase (LOX), secreted phosphoprotein 1 (SPP1) were identified as the specific fibrosis-associated genes for DN, IgAN and MN respectively. qRT-PCR demonstrated that the expression levels of these selected genes were consistent with the NanoString analysis.

CONCLUSIONS

There were both commonalities and differences in the mechanisms of fibrosis in different types of CKD, the commonalities might be used as the common therapeutic targets for kidney fibrosis in CKD, while the differences might be used as the diagnostic markers for DN, IgAN and MN respectively. Inflammation was highly relevant to the pathogenesis of fibrosis. This study provides further insight into the pathophysiology and treatment of fibrotic kidney disease.

Screening of active components in Astragalus mongholicus Bunge and Panax notoginseng formula for anti-fibrosis in CKD: nobiletin inhibits Lgals1/PI3K/AKT signaling to improve renal fibrosis

The Astragalus mongholicus Bunge and Panax notoginseng formula (A&P) has been clinically shown to effectively slow down the progression of chronic kidney disease (CKD) and has demonstrated significant anti-fibrosis effects in experimental CKD model. However, the specific active ingredients and underlying mechanism are still unclear. The active ingredients of A&P were analyzed by Ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-HR-MS). A mouse model of CKD was constructed by 5/6 nephrectomy. Renal function was assessed by creatinine and urea nitrogen. Real-time PCR and Western Blot were performed to detect the mRNA and protein changes in kidney and cells. An in vitro fibrotic cell model was constructed by TGF-β induction in TCMK-1 cells. The results showed that thirteen active ingredients of A&P were identified by UPLC-HR-MS, nine of which were identified by analysis with standards, among which the relative percentage of NOB was high. We found that NOB treatment significantly improved renal function, pathological damage and reduced the expression level of fibrotic factors in CKD mice. The results also demonstrated that Lgals1 was overexpressed in the interstitial kidney of CKD mice, and NOB treatment significantly reduced its expression level, while inhibiting PI3K and AKT phosphorylation. Interestingly, overexpression of Lgals1 significantly increased fibrosis in TCMK1 cells and upregulated the activity of PI3K and AKT, which were strongly inhibited by NOB treatment. NOB is one of the main active components of A&P. The molecular mechanism by which NOB ameliorates renal fibrosis in CKD may be through the inhibition of Lgals1/PI3K/AKT signaling pathway.