Inflammatory molecules and pathways in the pathogenesis of diabetic nephropathy

The effect and mechanism of freeze-dried powder of Poecilobdella manillensis on improving inflammatory injury of rat glomerular mesangial cells through TXNIP / NLRP3 pathway

Objective

Diabetic kidney disease (DKD) is a common complication of diabetes mellitus. The pathophysiological changes in platelet function and the hypercoagulable state associated with DKD are closely linked to inflammatory processes. Poecilobdella manillensis (PM), a type of leech known for its anticoagulant and antithrombotic properties, has the potential to modulate the inflammatory response in DKD. This study aims to investigate the effect of freeze-dried powder of PM on improving inflammatory injury in rat glomerular mesangial cells and to explore its underlying mechanism.

Methods

Lipopolysaccharide (LPS) stimulated HBZY-1 rat mesangial cells to establish an in vitro DKD inflammation model. After the intervention with the water extract of freeze-dried powder of PM (FDPM), cell viability, NO content, and the levels of inflammatory factors such as IL-1β, IL-18, and TNF-α were assessed. Finally, utilizing transcriptomics technology, RT-qPCR, and Western blot methods, the mechanism by which FDPM improves inflammatory injury in rat glomerular mesangial cells was explored and preliminarily validated.

Results

FDPM effectively enhances cell viability and inhibits the production of NO and related inflammatory factors. Transcriptomic analysis suggests that FDPM may exert these effects by regulating the TXNIP/NLRP3 signaling pathway. The mRNA and protein expressions of TXNIP, NLRP3, and MCP-1 in the model cells were reversed by FDPM.

Conclusion

FDPM may improve the micro-inflammatory state of DKD and slow the progression of the disease by regulating the TXNIP/NLRP3 signaling pathway. This study provides a scientific basis for the clinical application of PM DKD treatment.

Molecular Therapeutics for Diabetic Kidney Disease: An Update

Diabetic kidney disease (DKD) is a common microvascular complication of diabetes mellitus (DM). With the increasing prevalence of DM worldwide, the incidence of DKD remains high. If DKD is not well controlled, it can develop into chronic kidney disease or end-stage renal disease (ESRD), which places considerable economic pressure on society. Traditional therapies, including glycemic control, blood pressure control, blood lipid control, the use of renin-angiotensin system blockers and novel drugs, such as sodium-glucose cotransporter 2 inhibitors, mineralocorticoid receptor inhibitors and glucagon-like peptide-1 receptor agonists, have been used in DKD patients. Although the above treatment strategies can delay the progression of DKD, most DKD patients still ultimately progress to ESRD. Therefore, new and multimodal treatment methods need to be explored. In recent years, researchers have continuously developed new treatment methods and targets to delay the progression of DKD, including miRNA therapy, stem cell therapy, gene therapy, gut microbiota-targeted therapy and lifestyle intervention. These new molecular therapy methods constitute opportunities to better understand and treat DKD. In this review, we summarize the progress of molecular therapeutics for DKD, leading to new treatment strategies.

Corilagin alleviates podocyte injury in diabetic nephropathy by regulating autophagy via the SIRT1-AMPK pathway

BACKGROUND

Diabetic nephropathy (DN) is the most frequent chronic microvascular consequence of diabetes, and podocyte injury and malfunction are closely related to the development of DN. Studies have shown that corilagin (Cor) has hepatoprotective, anti-inflammatory, antibacterial, antioxidant, anti-hypertensive, anti-diabetic, and anti-tumor activities.

AIM

To explore the protective effect of Cor against podocyte injury in DN mice and the underlying mechanisms.

METHODS

Streptozotocin and a high-fat diet were combined to generate DN mice models, which were then divided into either a Cor group or a DN group (n = 8 in each group). Mice in the Cor group were intraperitoneally injected with Cor (30 mg/kg/d) for 12 wk, and mice in the DN group were treated with saline. Biochemical analysis was used to measure the blood lipid profiles. Hematoxylin and eosin staining was used to detect pathological changes in kidney tissue. Immunohistochemistry and Western blotting were used to assess the protein expression of nephrin and podocin. Mouse podocyte cells (MPC5) were cultured and treated with glucose (5 mmol/L), Cor (50 μM), high glucose (HG) (30 mmol/L), and HG (30 mmol/L) plus Cor (50 μM). Real-time quantitative PCR and Western blotting were performed to examine the effects of Cor on podocyte autophagy.

RESULTS

Compared with the control group, the DN mice models had increased fasting blood glucose, glycosylated hemoglobin, triglycerides, and total cholesterol, decreased nephrin and podocin expression, increased apoptosis rate, elevated inflammatory cytokines, and enhanced oxidative stress. All of the conditions mentioned above were alleviated after intervention with Cor. In addition, Cor therapy improved SIRT1 and AMPK expression (P < 0.001), inhibited reactive oxygen species and oxidative stress, and elevated autophagy in HG-induced podocytes (P < 0.01).

CONCLUSION

Cor alleviates podocyte injury by regulating autophagy via the SIRT1-AMPK pathway, thereby exerting its protective impact on renal function in DN mice.

Factor XII signaling via uPAR-integrin β1 axis promotes tubular senescence in diabetic kidney disease

Coagulation factor XII (FXII) conveys various functions as an active protease that promotes thrombosis and inflammation, and as a zymogen via surface receptors like urokinase-type plasminogen activator receptor (uPAR). While plasma levels of FXII are increased in diabetes mellitus and diabetic kidney disease (DKD), a pathogenic role of FXII in DKD remains unknown. Here we show that FXII is locally expressed in kidney tubular cells and that urinary FXII correlates with kidney dysfunction in DKD patients. F12-deficient mice (F12-/-) are protected from hyperglycemia-induced kidney injury. Mechanistically, FXII interacts with uPAR on tubular cells promoting integrin β1-dependent signaling. This signaling axis induces oxidative stress, persistent DNA damage and senescence. Blocking uPAR or integrin β1 ameliorates FXII-induced tubular cell injury. Our findings demonstrate that FXII-uPAR-integrin β1 signaling on tubular cells drives senescence. These findings imply previously undescribed diagnostic and therapeutic approaches to detect or treat DKD and possibly other senescence-associated diseases.

Dihydromyricetin ameliorates diabetic renal fibrosis via regulating SphK1 to suppress the activation of NF-κB pathway

Dihydromyricetin (DHM) is a flavonoid from vine tea with broad pharmacological benefits, which improve inflammation by blocking the NF-κB pathway. A growing body of research indicates that chronic kidney inflammation is vital to the pathogenesis of diabetic renal fibrosis. Sphingosine kinase-1 (SphK1) is a key regulator of diabetic renal inflammation, which triggers the NF-κB pathway. Hence, we evaluated whether DHM regulates diabetic renal inflammatory fibrosis by acting on SphK1. Here, we demonstrated that DHM effectively suppressed the synthesis of fibrotic and inflammatory adhesion factors like ICAM-1, and VCAM-1 in streptozotocin-treated high-fat diet-induced diabetic mice and HG-induced glomerular mesangial cells (GMCs). Moreover, DHM significantly suppressed NF-κB pathway activation and reduced SphK1 activity and protein expression under diabetic conditions. Mechanistically, the results of molecular docking, molecular dynamics simulation, and cellular thermal shift assay revealed that DHM stably bound to the binding pocket of SphK1, thereby reducing sphingosine-1-phosphate content and SphK1 enzymatic activity, which ultimately inhibited NF-κB DNA binding, transcriptional activity, and nuclear translocation. In conclusion, our data suggested that DHM inhibited SphK1 phosphorylation to prevent NF-κB activation thus ameliorating diabetic renal fibrosis. This supported the clinical use and further drug development of DHM as a potential candidate for treating diabetic renal fibrosis.

Association between systemic immune-inflammation index and cardiovascular-kidney-metabolic syndrome

This study aims to explore the relationship between the Systemic Immune-Inflammation Index (SII) and Cardiovascular-Kidney-Metabolic (CKM) Syndrome and its components. Data from the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2018 were analyzed. CKM Syndrome is defined as the coexistence of Cardiometabolic Syndrome (CMS) and Chronic Kidney Disease (CKD). The SII is calculated using the formula: SII = (Platelet count × Neutrophil count)/Lymphocyte count. Weighted logistic regression models were used to examine the associations between SII and CKM, as well as its specific components. Restricted cubic splines explored non-linear relationships, and piecewise linear regression models assessed threshold effects. A consistent positive correlation was observed between elevated SII levels and the likelihood of CKM and its related diseases. In the fully adjusted Model 3, an increase of 1000 units in SII was associated with a 1.48-fold increase in the odds of CKM (95% CI 1.20-1.81, p < 0.001). Quartile analysis revealed a dose-response relationship, with the highest quartile of SII (Q4) showing the strongest association with CKM and its components. Nonlinear analyses revealed inflection points for waist circumference, triglycerides, low HDL-C, and cardiometabolic syndrome at specific SII levels, indicating a change in the direction or strength of associations beyond these points. Conversely, a linear relationship was observed between SII and chronic kidney disease. The SII is positively correlated with the risk of CKM Syndrome and its individual components, with evidence of non-linear relationships and threshold effects for some components.

Role of Extracellular Vesicle-Derived Noncoding RNAs in Diabetic Kidney Disease

Background

Diabetic kidney disease (DKD), a metabolism-related syndrome characterized by abnormal glomerular filtration rate, proteinuria, and renal microangiopathy, is one of the most common forms of chronic kidney disease, whereas extracellular vesicles (EVs) have been recently evidenced as a novel cell communication player in DKD occurrence and progress via releasing various bioactive molecules, including proteins, lipids, and especially RNA, among which noncoding RNAs (including miRNAs, lncRNAs, and circRNAs) are the major regulators. However, the functional relevance of EV-derived ncRNAs in DKD is to be elucidated.

Summary

Studies have reported that EV-derived ncRNAs regulate gene expression via a diverse range of regulatory mechanisms, contributing to diverse phenotypes related to DKD progression. Furthermore, there are already many potential clinical diagnostic and therapeutic studies based on these ncRNAs, which can be expected to have potential applications in clinical practice for EV-derived ncRNAs.

Key Messages

In the current review, we summarized the mechanistic role of EVs in DKD according to biological function classifications, including inflammation and oxidative stress, epithelial-mesenchymal transition, cell death, and extracellular matrix deposition. In addition, we comprehensively discussed the potential applications of EV-derived ncRNAs as diagnostic biomarkers and therapeutic targets in DKD.

Investigating Interleukin-6 Levels in Type 2 Diabetes Mellitus Patients With and Without Diabetic Nephropathy

BACKGROUND AND OBJECTIVE

Diabetic nephropathy (DN), a severe complication affecting 40% of diabetic individuals, is a leading cause of chronic kidney disease (CKD). It involves a progressive increase in urinary albumin and a decline in the glomerular filtration rate. Early detection and intervention are crucial to preventing CKD progression. The current marker, albuminuria, measured as the urine albumin-to-creatinine ratio (UACR), has limitations, highlighting the need for alternative biomarkers. Researchers have linked the proinflammatory cytokine interleukin-6 (IL-6) to the progression of DN, observing elevated levels in DN patients compared to those without DN. IL-6 also regulates glucose metabolism, promoting insulin effectiveness and secretion. Inflammation and glucose control are two things that IL-6 does. This makes it a promising biomarker and therapeutic target for DN and type 2 diabetes mellitus (T2DM). This study focuses on IL-6 levels in T2DM patients with and without DN.

METHODS AND MATERIALS

From September 2022 to June 2024, the Department of General Medicine, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Dr. D. Y. Patil Vidyapeeth (Deemed to be University), Pune, conducted an observational cross-sectional comparative study on 80 T2DM patients, with 40 in group A (cases = T2DM patients with DN) and 40 in group B (controls = T2DM patients without DN). The study included patients with T2DM between the ages of 40 and 80. The study excludes conditions such as diabetic ketoacidosis, patients with end-stage renal disease, and conditions that increase IL-6, such as COVID-19. The study excluded autoimmune conditions with elevated IL-6, such as rheumatoid arthritis, systemic lupus erythematous, ankylosing spondylitis, psoriasis, and Crohn's disease. We obtained ethical approval and written consent from participants.

RESULTS

In the current study, 61 patients (76.2%) were 60 years old or younger, while 19 patients (23.8%) were older than 60 years. Among the participants, 38 were females (47.5%) and 42 were males (52.5%). The case group, which consisted of 40 T2DM patients with DN, had a mean glycated hemoglobin (HbA1c) of 7.1700 ± 0.71044. In contrast, the control group, comprising 40 T2DM patients without DN, had a mean HbA1c of 6.8650 ± 0.57179. This difference was statistically significant, with a p value of 0.038. Additionally, the mean UACR in the case group was 134.34 ± 95.56, significantly higher than the control group's mean UACR of 22.32 ± 9.90. This difference was highly significant, with a p value of 0.001. Furthermore, the case group exhibited elevated mean IL-6 levels of 15.48 ± 4.27 compared to the control group's 7.02 ± 2.46, which is also highly significant, reflected by a p value of 0.001.

CONCLUSION

As the concentration of IL-6 rises in diabetic patients with nephropathy, this study suggests that IL-6 may have an effect on the development of DN. This cytokine is necessary for both the initiation and progression of the condition. Using IL-6 as a supportive diagnostic test could help rule out other potential causes of DN in T2DM. Moreover, this marker does not require invasive procedures, and early measurement may help reduce mortality and morbidity.

Piperazine ferulate inhibits diabetic nephropathy by suppressing AGE/RAGE-mediated inflammatory signaling in rats and podocytes

Objective: Diabetic nephropathy (DN) is a serious complication that may occur during the later stages of diabetes, and can be further exacerbated by podocyte damage. Piperazine ferulate (PF) has well-defined nephroprotective effects and is used clinically in the treatment of chronic nephritis and other kidney diseases. However, the renoprotective effects and mechanisms of PF on DN are not clear. This study aims to investigate the protective effect of PF on DN and its mechanism of action, to inform the clinical application of PF in DN treatment. Methods: Network pharmacology was performed to predict the mechanism of action of PF in DN. Male Sprague Dawley rats were intraperitoneally injected with STZ (60 mg/kg) to establish a DN model, and then assessed for renal injury after 12 weeks of administration. In vitro, rat podocytes were treated with 25 mmol/L glucose and cultured for 24 h, followed by an assessment of cell injury. Results: Our results showed that PF significantly improved renal function, reduced renal pathological changes, decreased inflammatory response, and alleviated podocyte damage in DN rats. PF also attenuated glucose-induced podocyte injury in vitro. Regarding molecular mechanisms, our study demonstrated that PF downregulated the expression of genes and proteins related to AGE-RAGE-mediated inflammatory signaling. Conclusion: In summary, PF exerts its renoprotective effects by decreasing inflammation and protecting against podocyte injury through the inhibition of the AGE/RAGE/NF-κB/NLRP3 pathway. Overall, these data support the clinical potential of PF as a renoprotective agent in DN.

Advancements, Challenges, and clinical implications of integration of metabolomics technologies in diabetic nephropathy

BACKGROUND

Diabetic nephropathy (DN), a severe complication of diabetes, involves a range of renal abnormalities driven by metabolic derangements. Metabolomics, revealing dynamic metabolic shifts in diseases like DN and offering insights into personalized treatment strategies, emerges as a promising tool for improved diagnostics and therapies.

METHODS

We conducted an extensive literature review to examine how metabolomics contributes to the study of DN and the challenges associated with its implementation in clinical practice. We identified and assessed relevant studies that utilized metabolomics methods, including nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) to assess their efficacy in diagnosing DN.

RESULTS

Metabolomics unveils key pathways in DN progression, highlighting glucose metabolism, dyslipidemia, and mitochondrial dysfunction. Biomarkers like glycated albumin and free fatty acids offer insights into DN nuances, guiding potential treatments. Metabolomics detects small-molecule metabolites, revealing disease-specific patterns for personalized care.

CONCLUSION

Metabolomics offers valuable insights into the molecular mechanisms underlying DN progression and holds promise for personalized medicine approaches. Further research in this field is warranted to elucidate additional metabolic pathways and identify novel biomarkers for early detection and targeted therapeutic interventions in DN.

Circulating inflammatory factors and risk causality associated with type 2 diabetic nephropathy: A Mendelian randomization and bioinformatics study

The main causative factors of diabetic nephropathy (DN), a common complication of diabetes mellitus, are metabolic abnormalities and hemodynamic changes. However, studies have shown that the immune-inflammatory response also plays an important role in DN pathogenesis. Therefore, in this study, we analyzed the causal relationship and immune infiltration between inflammatory factors and DN using Mendelian randomization (MR) and bioinformatics techniques. We analyzed the causal relationship between 91 inflammatory factors and DN using two-sample MR dominated by the results of inverse variance-weighted analysis. Based on the MR analysis, the immune mechanism of inflammatory factors in DN was further explored using immune cell infiltration analysis. MR analysis indicated a positive causal relationship between DN and IL1A, caspase 8 (CASP8), macrophage colony-stimulating factor 1, IL10, STAM-binding protein, and tumor necrosis factor ligand superfamily member 12 (TNFSF12) and a negative causal relationship between DN and cystatin D, fibroblast growth factor 19, neurturin, and TNFSF14. The pathogenic mechanism of CASP8 may involve the recruitment of CD4+ T cells and macrophages for DN infiltration. In this study, we found a causal relationship between DN and IL1A, CASP8, macrophage colony-stimulating factor 1, IL10, STAM-binding protein, TNFSF12, cystatin D, fibroblast growth factor 19, neurturin, and TNFSF14. Bioinformatic immune infiltration analysis further revealed that CASP8 regulates DN by influencing the infiltration of immune cells, such as T cells and macrophages.

Modified Citrus Pectin (MCP) Confers a Renoprotective Effect on Early-Stage Nephropathy in Type-2 Diabetic Mice

Diabetic nephropathy (DN) is a significant global health concern with a high morbidity rate. Accumulating evidence reveals that Galectin-3 (Gal-3), a β-galactoside-binding lectin, is a biomarker in kidney diseases. Our study aimed to assess the advantageous impacts of modified citrus pectin (MCP) as an alternative therapeutic strategy for the initial and ongoing progression of DN in mice with type 2 diabetes mellitus (T2DM). The animal model has been split into four groups: control group, T2DM group (mice received intraperitoneal injections of nicotinamide (NA) and streptozotocin (STZ), T2DM+MCP group (mice received 100 mg/kg/day MCP following T2DM induction), and MCP group (mice received 100 mg/kg/day). After 4 weeks, kidney weight, blood glucose level, serum kidney function tests, histopathological structure alterations, oxidative stress, inflammation, apoptosis, and fibrosis parameters were determined in renal tissues. Our findings demonstrated that MCP treatment reduced blood glucose levels, renal histological damage, and restored kidney weight and kidney function tests. Additionally, MCP reduced malondialdehyde level and restored glutathione level, and catalase activity. MCP demonstrated a notable reduction in inflammatory and apoptosis mediators TNF-α, iNOS, TGF-βRII and caspase-3. Overall, MCP could alleviate renal injury in an experimental model of DN by suppressing renal oxidative stress, inflammation, fibrosis, and apoptosis mediators.

Identification of immune-associated biomarkers of diabetes nephropathy tubulointerstitial injury based on machine learning: a bioinformatics multi-chip integrated analysis

BACKGROUND

Diabetic nephropathy (DN) is a major microvascular complication of diabetes and has become the leading cause of end-stage renal disease worldwide. A considerable number of DN patients have experienced irreversible end-stage renal disease progression due to the inability to diagnose the disease early. Therefore, reliable biomarkers that are helpful for early diagnosis and treatment are identified. The migration of immune cells to the kidney is considered to be a key step in the progression of DN-related vascular injury. Therefore, finding markers in this process may be more helpful for the early diagnosis and progression prediction of DN.

METHODS

The gene chip data were retrieved from the GEO database using the search term ' diabetic nephropathy '. The ' limma ' software package was used to identify differentially expressed genes (DEGs) between DN and control samples. Gene set enrichment analysis (GSEA) was performed on genes obtained from the molecular characteristic database (MSigDB. The R package 'WGCNA' was used to identify gene modules associated with tubulointerstitial injury in DN, and it was crossed with immune-related DEGs to identify target genes. Gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed on differentially expressed genes using the 'ClusterProfiler' software package in R. Three methods, least absolute shrinkage and selection operator (LASSO), support vector machine recursive feature elimination (SVM-RFE) and random forest (RF), were used to select immune-related biomarkers for diagnosis. We retrieved the tubulointerstitial dataset from the Nephroseq database to construct an external validation dataset. Unsupervised clustering analysis of the expression levels of immune-related biomarkers was performed using the 'ConsensusClusterPlus 'R software package. The urine of patients who visited Dongzhimen Hospital of Beijing University of Chinese Medicine from September 2021 to March 2023 was collected, and Elisa was used to detect the mRNA expression level of immune-related biomarkers in urine. Pearson correlation analysis was used to detect the effect of immune-related biomarker expression on renal function in DN patients.

RESULTS

Four microarray datasets from the GEO database are included in the analysis : GSE30122, GSE47185, GSE99340 and GSE104954. These datasets included 63 DN patients and 55 healthy controls. A total of 9415 genes were detected in the data set. We found 153 differentially expressed immune-related genes, of which 112 genes were up-regulated, 41 genes were down-regulated, and 119 overlapping genes were identified. GO analysis showed that they were involved in various biological processes including leukocyte-mediated immunity. KEGG analysis showed that these target genes were mainly involved in the formation of phagosomes in Staphylococcus aureus infection. Among these 119 overlapping genes, machine learning results identified AGR2, CCR2, CEBPD, CISH, CX3CR1, DEFB1 and FSTL1 as potential tubulointerstitial immune-related biomarkers. External validation suggested that the above markers showed diagnostic efficacy in distinguishing DN patients from healthy controls. Clinical studies have shown that the expression of AGR2, CX3CR1 and FSTL1 in urine samples of DN patients is negatively correlated with GFR, the expression of CX3CR1 and FSTL1 in urine samples of DN is positively correlated with serum creatinine, while the expression of DEFB1 in urine samples of DN is negatively correlated with serum creatinine. In addition, the expression of CX3CR1 in DN urine samples was positively correlated with proteinuria, while the expression of DEFB1 in DN urine samples was negatively correlated with proteinuria. Finally, according to the level of proteinuria, DN patients were divided into nephrotic proteinuria group (n = 24) and subrenal proteinuria group. There were significant differences in urinary AGR2, CCR2 and DEFB1 between the two groups by unpaired t test (P < 0.05).

CONCLUSIONS

Our study provides new insights into the role of immune-related biomarkers in DN tubulointerstitial injury and provides potential targets for early diagnosis and treatment of DN patients. Seven different genes ( AGR2, CCR2, CEBPD, CISH, CX3CR1, DEFB1, FSTL1 ), as promising sensitive biomarkers, may affect the progression of DN by regulating immune inflammatory response. However, further comprehensive studies are needed to fully understand their exact molecular mechanisms and functional pathways in DN.

Strategies to address diabetic kidney disease burden in Mexico: a narrative review by the Mexican College of Nephrologists

Chronic kidney disease (CKD) is a growing global public health challenge worldwide. In Mexico, CKD prevalence is alarmingly high and remains a leading cause of morbidity and mortality. Diabetic kidney disease (DKD), a severe complication of diabetes, is a leading determinant of CKD. The escalating diabetes prevalence and the complex regional landscape in Mexico underscore the pressing need for tailored strategies to reduce the burden of CKD. This narrative review, endorsed by the Mexican College of Nephrologists, aims to provide a brief overview and specific strategies for healthcare providers regarding preventing, screening, and treating CKD in patients living with diabetes in all care settings. The key topics covered in this review include the main cardiometabolic contributors of DKD (overweight/obesity, hyperglycemia, arterial hypertension, and dyslipidemia), the identification of kidney-related damage markers, and the benefit of novel pharmacological approaches based on Sodium-Glucose Co-Transporter-2 Inhibitors (SGLT2i) and Glucagon-Like Peptide-1 Receptor Agonists (GLP-1 RA). We also address the potential use of novel therapies based on Mineralocorticoid Receptor Antagonists (MRAs) and their future implications. Emphasizing the importance of multidisciplinary treatment, this narrative review aims to promote strategies that may be useful to alleviate the burden of DKD and its associated complications. It underscores the critical role of healthcare providers and advocates for collaborative efforts to enhance the quality of life for millions of patients affected by DKD.

Clinical characteristics and treatment compounds of obesity-related kidney injury

Disorders in energy homeostasis can lead to various metabolic diseases, particularly obesity. The obesity epidemic has led to an increased incidence of obesity-related nephropathy (ORN), a distinct entity characterized by proteinuria, glomerulomegaly, progressive glomerulosclerosis, and renal function decline. Obesity and its associated renal damage are common in clinical practice, and their incidence is increasing and attracting great attention. There is a great need to identify safe and effective therapeutic modalities, and therapeutics using chemical compounds and natural products are receiving increasing attention. However, the summary is lacking about the specific effects and mechanisms of action of compounds in the treatment of ORN. In this review, we summarize the important clinical features and compound treatment strategies for obesity and obesity-induced kidney injury. We also summarize the pathologic and clinical features of ORN as well as its pathogenesis and potential therapeutics targeting renal inflammation, oxidative stress, insulin resistance, fibrosis, kidney lipid accumulation, and dysregulated autophagy. In addition, detailed information on natural and synthetic compounds used for the treatment of obesity-related kidney disease is summarized. The synthesis of detailed information aims to contribute to a deeper understanding of the clinical treatment modalities for obesity-related kidney diseases, fostering the anticipation of novel insights in this domain.

Zn(II)-curcumin prevents cadmium-aggravated diabetic nephropathy by regulating gut microbiota and zinc homeostasis

Background: Diabetic nephropathy (DN) is known as the most common complication of diabetes, resulting from a complex inheritance-environment interaction without effective clinical treatments. Herein, we revealed the protective effects and mechanisms of Zn(II)-curcumin, a curcumin derivative, against streptozotocin-induced DN in rats in the presence or absence of cadmium exposure. Methods: The present study focused on investigating the therapy of Zn(II)-curcumin against cadmium-aggravated DN by regulating gut microbiota, metabolism, inflammation and zinc homeostasis based on pathological changes, TLR4/NF-κB signaling pathway, inductively coupled plasma-mass spectrometry (ICP-MS), 16S rRNA gene sequencing and gas chromatography-mass spectrometer (GC-MS). Results: We found Zn(II)-curcumin significantly mitigated the cadmium-aggravated phenotypes of diabetic nephropathy, as indicated by the remission of renal dysfunction, pathological changes, inflammation and zinc dyshomeostasis in streptozotocin-treated rats exposed to cadmium. Administration of Zn(II)-curcumin significantly alleviated the dysbiosis of gut microbiota and the changes of serum metabolite profiles in rats treated with streptozotocin in combination with cadmium. Notably, fecal microbial transplantation identified the ability of Zn(II)-curcumin to regulate renal function, inflammation and zinc homeostasis was partly dependent on the gut microbiota. Conclusion: These findings revealed that Zn(II)-curcumin alleviated cadmium-aggravated diabetic nephropathy by reshaping the gut microbiota and zinc homeostasis, which provided unique insights into the mechanisms of the treatment and prevention of diabetic nephropathy.

Anti-inflammatory benefits of semaglutide: State of the art

Individuals with diabetes often have chronic inflammation and high levels of inflammatory cytokines, leading to insulin resistance and complications. Anti-inflammatory agents are proposed to prevent these issues, including using antidiabetic medications with anti-inflammatory properties like semaglutide, a GLP-1 analogue. Semaglutide not only lowers glucose but also shows potential anti-inflammatory effects. Studies suggest it can modulate inflammatory responses and benefit those with diabetes. However, the exact mechanisms of its anti-inflammatory effects are not fully understood. This review aims to discuss the latest findings on semaglutide's anti-inflammatory effects and the potential pathways involved.

Scutellarin ameliorates diabetic nephropathy via TGF-β1 signaling pathway

Breviscapine, a natural flavonoid mixture derived from the traditional Chinese herb Erigeron breviscapus (Vant.) Hand-Mazz, has demonstrated a promising potential in improving diabetic nephropathy (DN). However, the specific active constituent(s) responsible for its therapeutic effects and the underlying pharmacological mechanisms remain unclear. In this study, we aimed to investigate the impact of scutellarin, a constituent of breviscapine, on streptozotocin-induced diabetic nephropathy and elucidate its pharmacological mechanism(s). Our findings demonstrate that scutellarin effectively ameliorates various features of DN in vivo, including proteinuria, glomerular expansion, mesangial matrix accumulation, renal fibrosis, and podocyte injury. Mechanistically, scutellarin appears to exert its beneficial effects through modulation of the transforming growth factor-β1 (TGF-β1) signaling pathway, as well as its interaction with the extracellular signal-regulated kinase (Erk) and Wnt/β-catenin pathways.

Cross-Domain Text Mining of Pathophysiological Processes Associated with Diabetic Kidney Disease

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease worldwide. This study's goal was to identify the signaling drivers and pathways that modulate glomerular endothelial dysfunction in DKD via artificial intelligence-enabled literature-based discovery. Cross-domain text mining of 33+ million PubMed articles was performed with SemNet 2.0 to identify and rank multi-scalar and multi-factorial pathophysiological concepts related to DKD. A set of identified relevant genes and proteins that regulate different pathological events associated with DKD were analyzed and ranked using normalized mean HeteSim scores. High-ranking genes and proteins intersected three domains-DKD, the immune response, and glomerular endothelial cells. The top 10% of ranked concepts were mapped to the following biological functions: angiogenesis, apoptotic processes, cell adhesion, chemotaxis, growth factor signaling, vascular permeability, the nitric oxide response, oxidative stress, the cytokine response, macrophage signaling, NFκB factor activity, the TLR pathway, glucose metabolism, the inflammatory response, the ERK/MAPK signaling response, the JAK/STAT pathway, the T-cell-mediated response, the WNT/β-catenin pathway, the renin-angiotensin system, and NADPH oxidase activity. High-ranking genes and proteins were used to generate a protein-protein interaction network. The study results prioritized interactions or molecules involved in dysregulated signaling in DKD, which can be further assessed through biochemical network models or experiments.

Mitochondrial DNA and Inflammation Are Associated with Cerebral Vessel Remodeling and Early Diabetic Kidney Disease in Patients with Type 2 Diabetes Mellitus

Cerebrovascular disease accounts for major neurologic disabilities in patients with type 2 diabetes mellitus (DM). A potential association of mitochondrial DNA (mtDNA) and inflammation with cerebral vessel remodeling in patients with type 2 DM was evaluated. A cohort of 150 patients and 30 healthy controls were assessed concerning urinary albumin/creatinine ratio (UACR), synaptopodin, podocalyxin, kidney injury molecule-1 (KIM-1), N-acetyl-β-(D)-glucosaminidase (NAG), interleukins IL-17A, IL-18, IL-10, tumor necrosis factor-alpha (TNFα), intercellular adhesion molecule-1 (ICAM-1). MtDNA-CN and nuclear DNA (nDNA) were quantified in peripheral blood and urine by qRT-PCR. Cytochrome b (CYTB) gene, subunit 2 of NADH dehydrogenase (ND2), and beta 2 microglobulin nuclear gene (B2M) were assessed by TaqMan assays. mtDNA-CN was defined as the ratio of the number of mtDNA/nDNA copies, through analysis of the CYTB/B2M and ND2/B2M ratio; cerebral Doppler ultrasound: intima-media thickness (IMT)-the common carotid arteries (CCAs), the pulsatility index (PI) and resistivity index (RI)- the internal carotid arteries (ICAs) and middle cerebral arteries (MCAs), the breath-holding index (BHI). The results showed direct correlations of CCAs-IMT, PI-ICAs, PI-MCAs, RI-ICAs, RI-MCAs with urinary mtDNA, IL-17A, IL-18, TNFα, ICAM-1, UACR, synaptopodin, podocalyxin, KIM-1, NAG, and indirect correlations with serum mtDNA, IL-10. BHI correlated directly with serum IL-10, and serum mtDNA, and negatively with serum IL-17A, serum ICAM-1, and NAG. In neurologically asymptomatic patients with type 2 DM cerebrovascular remodeling and impaired cerebrovascular reactivity may be associated with mtDNA variations and inflammation from the early stages of diabetic kidney disease.

Targeting Macrophages: Therapeutic Approaches in Diabetic Kidney Disease

Diabetes is not solely a metabolic disorder but also involves inflammatory processes. The immune response it incites is a primary contributor to damage in target organs. Research indicates that during the initial phases of diabetic nephropathy, macrophages infiltrate the kidneys alongside lymphocytes, initiating a cascade of inflammatory reactions. The interplay between macrophages and other renal cells is pivotal in the advancement of kidney disease within a hyperglycemic milieu. While M1 macrophages react to the inflammatory stimuli induced by elevated glucose levels early in the disease progression, their subsequent transition to M2 macrophages, which possess anti-inflammatory and tissue repair properties, also contributes to fibrosis in the later stages of nephropathy by transforming into myofibroblasts. Comprehending the diverse functions of macrophages in diabetic kidney disease and regulating their activity could offer therapeutic benefits for managing this condition.

Human umbilical cord mesenchymal stem cell-derived exosomes ameliorate renal fibrosis in diabetic nephropathy by targeting Hedgehog/SMO signaling

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease globally. Currently, there are no effective drugs for the treatment of DN. Although several studies have reported the therapeutic potential of mesenchymal stem cells, the underlying mechanisms remain largely unknown. Here, we report that both human umbilical cord MSCs (UC-MSCs) and UC-MSC-derived exosomes (UC-MSC-exo) attenuate kidney damage, and inhibit epithelial-mesenchymal transition (EMT) and renal fibrosis in streptozotocin-induced DN rats. Strikingly, the Hedgehog receptor, smoothened (SMO), was significantly upregulated in the kidney tissues of DN patients and rats, and positively correlated with EMT and renal fibrosis. UC-MSC and UC-MSC-exo treatment resulted in decrease of SMO expression. In vitro co-culture experiments revealed that UC-MSC-exo reduced EMT of tubular epithelial cells through inhibiting Hedgehog/SMO pathway. Collectively, UC-MSCs inhibit EMT and renal fibrosis by delivering exosomes and targeting Hedgehog/SMO signaling, suggesting that UC-MSCs and their exosomes are novel anti-fibrotic therapeutics for treating DN.

Jiawei Shengjiangsan's Effect on Renal Injury in Diabetic Nephropathy Mice is Investigated via the PI3K/Akt/NF-κB Signaling Pathway

Purpose

This study aimed to investigate the intervention mechanism of Jiawei Shengjiangsan (JWSJS) on kidney injury in diabetic nephropathy mice.

Methods

Thirty 8-week-old db/db mice were randomly divided into five groups: model group, Perindopril group, and JWSJS low-, medium-, and high-dose groups (n=6 per group) based on body weight. Additionally, a blank control group was established consisting of 6 db/m mice aged 8 weeks. The blank and model groups received daily intragastric administration of 7g/kg/d pure water. The remaining groups were assigned to JWSJS low (3.5g/kg/d), medium (7g/kg/d), high (14g/kg/d) dosage groups, and perindopril positive control group (0.48mg/kg/d) for 12 weeks. Post-experiment, serum creatinine (SCr) and blood urea nitrogen (BUN) were analyzed using an automatic biochemical analyzer. Enzyme-linked immunosorbent assay (ELISA) measured 24-hour urinary albumin, neutrophil gelatinase-associated lipocalin (NGAL), TNF-α, IL-1β, VCAM-1, MCP-1, and HbA1c. Western blot assessed the protein expressions of p-PI3K, p-Akt, and p-NF-κB p65, while pathological kidney changes were observed.

Results

Compared to the blank group, the model group exhibited increased SCr, BUN, 24-hour urinary albumin, serum NGAL, TNF-α, IL-1β, VCAM-1, MCP-1, HbA1c, p-PI3K, and p-Akt, alongside increased p-NF-κB p65 expression, indicating significant kidney pathology. After treatment, the JWSJS group showed decreased SCr, BUN, 24-hour urinary microalbumin, NGAL, HbA1c, TNF-α, IL-1β, VCAM-1, MCP-1 levels, increased p-PI3K and p-Akt expression (P<0.05), and reduced p-NF-κB p65 content (P<0.05). Histopathological analysis revealed that JWSJS ameliorated renal tubular epithelial cell damage, glomerular capillary and basement membrane injuries, and facilitated the repair of damaged podocytes in diabetic nephropathy mice.

Conclusion

JWSJS demonstrated efficacy in reducing renal inflammation in diabetic nephropathy mice, with its mechanism likely associated with the inhibition of the PI3K/Akt/NF-κB signaling pathway.

Phloretamide Protects against Diabetic Kidney Damage and Dysfunction in Diabetic Rats by Attenuating Hyperglycemia and Hyperlipidemia, Suppressing NF-κβ, and Upregulating Nrf2

Potent hypoglycemic and antioxidant effects were recently reported for the apple-derived phenolic compound phloretamide (PLTM). The renoprotective effects of this compound are yet to be shown. This study aimed to examine the potential of PLTM to prevent diabetic nephropathy in streptozotocin-induced diabetic rats and to examine the possible mechanisms of protection. Non-diabetic and STZ-diabetic male rats were treated orally by gavage with either the vehicle or with PTLM (200 mg/kg; twice/week) for 12 weeks. PTLM significantly increased urine volume and prevented glomerular and tubular damage and vacuolization in STZ-diabetic rats. It also increased creatinine excretion and reduced urinary albumin levels and the renal levels of kidney injury molecule-1 (KIM-1), 8-hydroxy-2'-deoxyguanosine (8-OHdG), neutrophil gelatinase-associated lipocalin (NGAL), and nephrin in the diabetic rats. PTLM also prevented an increase in the nuclear levels of NF-κβ, as well as the total levels of tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), caspase-3, and Bax in the kidneys of diabetic rats. These effects were associated with reduced serum levels of triglycerides, cholesterol, and low-density lipoprotein cholesterol. In both the control and diabetic rats, PTLM significantly reduced fasting plasma glucose and enhanced the renal mRNA and cytoplasmic levels of Nrf2, as well as the levels of Bcl2, superoxide dismutase (SOD), and glutathione (GSH). However, PTLM failed to alter the cytoplasmic levels of keap1 in diabetic rats. In conclusion, PTLM prevents renal damage and dysfunction in STZ-diabetic rats through its hypoglycemic and hypolipidemic activities, as well as through its antioxidant potential, which is mediated by activating the Nrf2/antioxidant axis.

Single-cell transcriptomics reveals the ameliorative effect of rosmarinic acid on diabetic nephropathy-induced kidney injury by modulating oxidative stress and inflammation

Diabetic nephropathy (DN) is a severe complication of diabetes, characterized by changes in kidney structure and function. The natural product rosmarinic acid (RA) has demonstrated therapeutic effects, including anti-inflammation and anti-oxidative-stress, in renal damage or dysfunction. In this study, we characterized the heterogeneity of the cellular response in kidneys to DN-induced injury and RA treatment at single cell levels. Our results demonstrated that RA significantly alleviated renal tubular epithelial injury, particularly in the proximal tubular S1 segment and on glomerular epithelial cells known as podocytes, while attenuating the inflammatory response of macrophages, oxidative stress, and cytotoxicity of natural killer cells. These findings provide a comprehensive understanding of the mechanisms by which RA alleviates kidney damage, oxidative stress, and inflammation, offering valuable guidance for the clinical application of RA in the treatment of DN.

Adipose stem cells control obesity-induced T cell infiltration into adipose tissue

T cell infiltration into white adipose tissue (WAT) drives obesity-induced adipose inflammation, but the mechanisms of obesity-induced T cell infiltration into WAT remain unclear. Our single-cell RNA sequencing reveals a significant impact of adipose stem cells (ASCs) on T cells. Transplanting ASCs from obese mice into WAT enhances T cell accumulation. C-C motif chemokine ligand 5 (CCL5) is upregulated in ASCs as early as 4 weeks of high-fat diet feeding, coinciding with the onset of T cell infiltration into WAT during obesity. ASCs and bone marrow transplantation experiments demonstrate that CCL5 from ASCs plays a crucial role in T cell accumulation during obesity. The production of CCL5 in ASCs is induced by tumor necrosis factor alpha via the nuclear factor κB pathway. Overall, our findings underscore the pivotal role of ASCs in regulating T cell accumulation in WAT during the early phases of obesity, emphasizing their importance in modulating adaptive immunity in obesity-induced adipose inflammation.

Astragaloside IV attenuates renal tubule injury in DKD rats via suppression of CD36-mediated NLRP3 inflammasome activation

Background

In recent years, diabetic kidney disease (DKD) has emerged as a prominent factor contributing to end-stage renal disease. Tubulointerstitial inflammation and lipid accumulation have been identified as key factors in the development of DKD. Earlier research indicated that Astragaloside IV (AS-IV) reduces inflammation and oxidative stress, controls lipid accumulation, and provides protection to the kidneys. Nevertheless, the mechanisms responsible for its protective effects against DKD have not yet been completely elucidated.

Purpose

The primary objective of this research was to examine the protective properties of AS-IV against DKD and investigate the underlying mechanism, which involves CD36, reactive oxygen species (ROS), NLR family pyrin domain containing 3 (NLRP3), and interleukin-1β (IL-1β).

Methods

The DKD rat model was created by administering streptozotocin along with a high-fat diet. Subsequently, the DKD rats and palmitic acid (PA)-induced HK-2 cells were treated with AS-IV. Atorvastatin was used as the positive control. To assess the therapeutic effects of AS-IV on DKD, various tests including blood sugar levels, the lipid profile, renal function, and histopathological examinations were conducted. The levels of CD36, ROS, NLRP3, Caspase-1, and IL-1β were detected using western blot analysis, PCR, and flow cytometry. Furthermore, adenovirus-mediated CD36 overexpression was applied to explore the underlying mechanisms through in vitro experiments.

Results

In vivo experiments demonstrated that AS-IV significantly reduced hyperglycemia, dyslipidemia, urinary albumin excretion, and serum creatinine levels in DKD rats. Additionally, it improved renal structural abnormalities and suppressed the expression of CD36, NLRP3, IL-1β, TNF-α, and MCP-1. In vitro experiments showed that AS-IV decreased CD36 expression, lipid accumulation, and lipid ROS production while inhibiting NLRP3 activation and IL-1β secretion in PA-induced HK-2 cells.

Conclusion

AS-IV alleviated renal tubule interstitial inflammation and tubule epithelial cell apoptosis in DKD rats by inhibiting CD36-mediated lipid accumulation and NLRP3 inflammasome activation.

Jian-Pi-Gu-Shen-Hua-Yu Decoction Alleviated Diabetic Nephropathy in Mice through Reducing Ferroptosis

Background

Diabetic nephropathy (DN), one of the most frequent complications of diabetes mellitus, is a leading cause of end-stage renal disease. However, the current treatment methods still cannot effectively halt the progression of DN. Jian-Pi-Gu-Shen-Hua-Yu (JPGS) decoction can be used for the treatment of chronic kidney diseases such as DN, but the specific mechanism of action has not been fully elucidated yet.

Purpose

The aim of this study is to clarify whether JPGS alleviates the progression of diabetic nephropathy by inhibiting ferroptosis.

Materials and Methods

We established a DN mouse model to investigate the therapeutic effect of JPGS in a DN mouse model. Subsequently, we examined the effects of JPGS on ferroptosis- and glutathione peroxidase 4 (GPX4) pathway-related indices. Finally, we validated whether JPGS inhibited ferroptosis in DN mice via the GPX4 pathway using GPX4 inhibitor and ferroptosis inhibitors.

Results

The results indicate that JPGS has a therapeutic effect on DN mice by improving kidney function and reducing inflammation. Additionally, JPGS treatment decreased iron overload and oxidative stress levels while upregulating the expression of GPX4 pathway-related proteins. Moreover, JPGS demonstrated a similar therapeutic effect as Fer-1 in the context of DN treatment, and RSL3 was able to counteract the therapeutic effect of JPGS and antiferroptotic effect.

Conclusion

JPGS has significant therapeutic and anti-inflammatory effects on DN mice, and its mechanism is mainly achieved by upregulating the expression of GPX4 pathway-related proteins, thereby alleviating iron overload and ultimately reducing ferroptosis.

2-Dodecyl-6-Methoxycyclohexa-2, 5-Diene-1, 4-Dione isolated from Averrhoa carambola L. root inhibits high glucose-induced EMT in HK-2 cells through targeting the regulation of miR-21-5p/Smad7 signaling pathway

OBJECTIVE

2-Dodecyl-6-Methoxycyclohexa-2, 5-Diene-1, 4-Dione (DMDD) isolated from Averrhoa carambola L. root, has been proven therapeutic effects on diabetic kidney disease (DKD). This research aims to assess DMDD's effects on DKD and to investigate its underlying mechanisms, to establish DMDD as a novel pharmaceutical agent for DKD treatment.

METHODS

The human renal tubular epithelial (HK-2) cells were induced by high glucose (HG) to mimic DKD and followed by DMDD treatment. The cytotoxicity of DMDD was assessed using the Cell Counting Kit-8 (CCK-8) assay. The migratory capacity of HK-2 cells was evaluated through transwell and scratch-wound assays. To investigate the effect of Smad7 and miR-21-5p, lentiviral transfection was employed in HK-2 cells. Additionally, the expression of proteins related to epithelial-mesenchymal transition (EMT) and TGFβ1/Smad2/3 pathway was checked by QRT-PCR, Western blot, and immunofluorescence techniques.

RESULTS

This study has shown that DMDD significantly suppresses cell migration and the expression of Vimentin, α-SMA, TGFβ1, and p-Smad2/3 in HK-2 cells under HG conditions. Concurrently, DMDD enhances the protein expression of E-cadherin and Smad7. Intriguingly, the therapeutic effect of DMDD was abrogated upon Smad7 silencing. Further investigations revealed that DMDD effectively inhibits miR-21-5p expression, which is upregulated by HG. Downregulation of miR-21-5p inhibits the activation of the TGFβ1/Smad2/3 pathway and EMT induced by HG. In contrast, overexpression of miR-21-5p negates DMDD's therapeutic benefits.

CONCLUSION

DMDD mitigates EMT in HG-induced HK-2 cells by modulating the miR-21-5p/Smad7 pathway, thereby inhibiting renal fibrosis in DKD. These findings suggest that DMDD holds promise as a potential therapeutic agent for DKD.

Visceral adipose tissue and risk of diabetic nephropathy: A Mendelian randomization study

OBJECTIVE

Previous observational studies have established a correlation between visceral adipose tissue (VAT) and diabetic nephropathy (DN). However, the causality of this association remains unclear. Therefore, the aim of this study was to investigate the causal association between VAT and DN by employing two-sample Mendelian randomization (MR) methods.

METHODS

The primary MR approach employed was the random-effects inverse-variance weighted (IVW) method. Additionally, we employed alternative methods, including the weighted median (WM) approach, MR-Egger regression, and Mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO). Sensitivity analyses were conducted to evaluate the robustness of the MR analyses.

RESULTS

Genetically predicted higher VAT mass was causally associated with a higher risk of DN. The results of the MR analyses were as follows: IVW(Beta = 0.948, odds ratio (OR) = 2.581, 95 % confidence interval (CI) = 2.100-3.173, p = 1.980e-19), WM (Beta = 1.126, OR = 3.082, 95 % CI = 2.278-4.171, p = 2.997e-13), MR-Egger (Beta = 1.315, OR = 3.724, 95 % CI = 1.981-6.998, p = 6.446e-05), and MR-PRESSO (Beta = 0.914, OR = 2.493, 95 % CI = 2.292-2.695, p = 3.121e-16). No pleiotropy was detected (p = 0.230).

CONCLUSIONS

This study provided genetic evidence that higher VAT mass was causally associated with a higher risk of DN.

Impaired kidney function and the risk of all-cause mortality and cardiovascular disease among Chinese hypertensive adults: Using three different equations to estimate the glomerular filtration rate

OBJECTIVES

We aimed to seek accurate assessments of the glomerular filtration rate (GFR) in a Chinese hypertensive population to identify individuals at high risk for chronic kidney disease (CKD) progression. Then, the risk of cardiovascular disease (CVD) and all-cause death due to kidney injury were further investigated under appropriate GFR-estimation equations.

METHODS

In this prospective follow-up cohort study of 10,171 hypertensive patients, we compared the discrimination power of a trio of GFR-estimation equations using Harrell's C-index, measuring the model fit by calculating the Akaike information criterion. Univariate and multivariable logistic regression analyses were respectively used to calculate the hazard ratio (HR) and 95% confidence interval [CI] values for CKD progression. In addition, we also assessed the risk of CVD and all-cause death with impaired renal function using multivariable-adjusted Cox regression models.

RESULTS

The Modification of Diet in Renal Disease (MDRD) equation showed the highest C-index range for the predicted probability of CKD progression in the fully adjusted model. During MDRD analysis, a low eGFR (60-89 mL/min/1.73m2 or < 60 mL/min/1.73m2) was an independent risk factor for CVD, especially stroke (1.28 [95% CI, 1.05-1.55] and 1.89 [95% CI, 1.08-3.31]), as well as all-cause mortality (1.28 [95% CI, 1.09-1.50] and 1.68 [95% CI, 1.01-2.78]).

CONCLUSIONS

The MDRD equation seems to be more suitable for screening CKD progression in Chinese hypertensive populations, targeting potential risk factors for effective prevention to reduce renal impairment so as to further limit CVD morbidity and mortality.

A clinical study on roxadustat for anemia in diabetic nephropathy: a 8-week study

PURPOSE

The development of roxadustat is a standard treatment for renal anemia, and multiple clinical trials have proved its safety and efficacy. However, less information is available from trials of the population with diabetic nephropathy (DN). This study aimed to determine whether roxadustat is effective for treating DN.

METHODS

This was a single-center, retrospective, institutional review board-approved cohort study. The patients with DN were chosen and given roxadustat or erythropoietin (EPO) for 8 weeks. The mean hemoglobin (Hb) level after 8 weeks of treatment served as the primary outcome. Alterations in the iron index and lipid levels were considered secondary objectives. Sub-group analysis was performed to observe the impact of inflammation and glycemic status on Hb.

RESULTS

A total of 80 patients were enrolled, 40 in each group. After 8 weeks of treatment, the Hb levels in the roxadustat group were higher than those in the control group. The number of patients who achieved Hb response was higher in the roxadustat group than in the control group (77.5% versus 27.5%; P < 0.001). In addition to lowering total cholesterol and low-density lipoprotein cholesterol, roxadustat decreased ferritin and elevated total iron-binding capacity. Compared to the control group, roxadustat was more beneficial for patients with an inflammatory condition and poor glycemic control.

CONCLUSIONS

Roxadustat treatment remarkably corrected anemia in patients with DN, and its effectiveness was unaffected by inflammation or glycemic control levels. In addition, roxadustat can also reduce a patient's blood lipid level and enhance the body's use of iron.

CLINICAL TRIAL REGISTRATION

ChiCTR2200057232.

Bone marrow-derived c-kit positive stem cell administration protects against diabetes-induced nephropathy in a rat model by reversing PI3K/AKT/GSK-3β pathway and inhibiting cell apoptosis

Stem cell-based therapy has been proposed as a novel therapeutic strategy for diabetic nephropathy. This study was designed to evaluate the effect of systemic administration of rat bone marrow-derived c-kit positive (c-kit+) cells on diabetic nephropathy in male rats, focusing on PI3K/AKT/GSK-3β pathway and apoptosis as a possible therapeutic mechanism. Twenty-eight animals were randomly classified into four groups: Control group (C), diabetic group (D), diabetic group, intravenously received 50 μl phosphate-buffered saline (PBS) containing 3 × 105 c-kit- cells (D + ckit-); and diabetic group, intravenously received 50 μl PBS containing 3 × 105 c-Kit positive cells (D + ckit+). Control and diabetic groups intravenously received 50 μl PBS. C-kit+ cell therapy could reduce renal fibrosis, which was associated with attenuation of inflammation as indicated by decreased TNF-α and IL-6 levels in the kidney tissue. In addition, c-kit+ cells restored the expression levels of PI3K, pAKT, and GSK-3β proteins. Furthermore, renal apoptosis was decreased following c-kit+ cell therapy, evidenced by the lower apoptotic index in parallel with the increased Bcl-2 and decreased Bax and Caspase-3 levels. Our results showed that in contrast to c-kit- cells, the administration of c-kit+ cells ameliorate diabetic nephropathy and suggested that c-kit+ cells could be an alternative cell source for attenuating diabetic nephropathy.

Parallelism and non-parallelism in diabetic nephropathy and diabetic retinopathy

Diabetic nephropathy (DN) and diabetic retinopathy (DR), as microvascular complications of diabetes mellitus, are currently the leading causes of end-stage renal disease (ESRD) and blindness, respectively, in the adult working population, and they are major public health problems with social and economic burdens. The parallelism between the two in the process of occurrence and development manifests in the high overlap of disease-causing risk factors and pathogenesis, high rates of comorbidity, mutually predictive effects, and partial concordance in the clinical use of medications. However, since the two organs, the eye and the kidney, have their unique internal environment and physiological processes, each with specific influencing molecules, and the target organs have non-parallelism due to different pathological changes and responses to various influencing factors, this article provides an overview of the parallelism and non-parallelism between DN and DR to further recognize the commonalities and differences between the two diseases and provide references for early diagnosis, clinical guidance on the use of medication, and the development of new drugs.

Role of novel biomarker monocyte chemo-attractant protein-1 in early diagnosis & predicting progression of diabetic kidney disease: A comprehensive review

Diabetic kidney disease (DKD) is the most devastating complication of diabetes mellitus. Identification of patients at the early stages of progression may reduce the disease burden. The limitation of conventional markers such as serum creatinine and proteinuria intensify the need for novel biomarkers. The traditional paradigm of DKD pathogenesis has expanded to the activation of the immune system and inflammatory pathways. Monocyte chemo-attractant protein-1 (MCP-1) is extensively studied, as a key inflammatory mediator that modulates the development of DKD. Recent evidence supports the diagnostic role of MCP-1 in patients with or without proteinuria in DKD, as well as a significant role in the early prediction and risk stratification of DKD. In this review, we will summarize and update present evidence for MCP-1 for diagnostic ability and predicting the progression of DKD.

Effect of human umbilical cord blood-mesenchymal stem cells on cisplatin-induced nephrotoxicity in rats

BACKGROUND

Cisplatin-containing regimen is an effective treatment for several malignancies. However, cisplatin is an important cause of nephrotoxicity. So, many trials were performed to transplant stem cells systemically or locally to control cisplatin-induced nephrotoxicity. Stem cell therapeutic effect may be dependent on the regulation of inflammation and oxidant stress.

AIM

To investigate the effect of human umbilical cord blood-mesenchymal stem cells (hUCB-MSCs) on the histological structure, the oxidant stress, and the inflammatory gene expression in an experimental model of cisplatin-induced nephrotoxicity in rats.

METHOD

The rats were divided into 6 equal groups (each of 10 rats): Group I included normal rats that received no treatment. Group II included healthy rats that received IV hUCB-MSCs. Group III included untreated cisplatin-induced nephrotoxic rats. Group IV included cisplatin-induced nephrotoxic rats that received magnesium (Mg) injections after injury. Group V was injected with hUCB-MSCs after injury. Group VI received both Mg and hUCB-MSCs after injury. In tissue homogenates, reduced glutathione (GSH), superoxide dismutase (SOD), and malondialdehyde (MDA) activities were measured. Quantitative real-time-polymerase chain reaction (qRT-PCR) was performed to assess iNOS, TLR4, and NF-kB gene expression. Hematoxylin and eosin (H&E) staining was performed to study the histological structure of the kidney. Immunohistochemical staining of iNOS and NF-κB was performed, as well.

RESULTS

Disturbed kidney functions, oxidative status, and histological structure were seen in the rats that received cisplatin. Treated groups showed improvements in kidney functions, oxidative status, and histological structure, particularly in the combined treatment group.

CONCLUSION

In the cisplatin-induced nephrotoxicity model, hUCB-MSCs could improve the functional and morphological kidney structure by modulation of oxidative and inflammatory status.

Complement Cascade Proteins Correlate with Fibrosis and Inflammation in Early-Stage Type 1 Diabetic Kidney Disease in the Ins2Akita Mouse Model

Diabetic kidney disease (DKD) is characterized by histological changes including fibrosis and inflammation. Evidence supports that DKD is mediated by the innate immune system and more specifically by the complement system. Using Ins2Akita T1D diabetic mice, we studied the connection between the complement cascade, inflammation, and fibrosis in early DKD. Data were extracted from a previously published quantitative-mass-spectrometry-based proteomics analysis of kidney glomeruli of 2 (early DKD) and 4 months (moderately advanced DKD)-old Ins2Akita mice and their controls A Spearman rho correlation analysis of complement- versus inflammation- and fibrosis-related protein expression was performed. A cross-omics validation of the correlation analyses' results was performed using public-domain transcriptomics datasets (Nephroseq). Tissue sections from 43 patients with DKD were analyzed using immunofluorescence. Among the differentially expressed proteins, the complement cascade proteins C3, C4B, and IGHM were significantly increased in both early and later stages of DKD. Inflammation-related proteins were mainly upregulated in early DKD, and fibrotic proteins were induced in moderately advanced stages of DKD. The abundance of complement proteins with fibrosis- and inflammation-related proteins was mostly positively correlated in early stages of DKD. This was confirmed in seven additional human and mouse transcriptomics DKD datasets. Moreover, C3 and IGHM mRNA levels were found to be negatively correlated with the estimated glomerular filtration rate (range for C3 rs = -0.58 to -0.842 and range for IGHM rs = -0.6 to -0.74) in these datasets. Immunohistology of human kidney biopsies revealed that C3, C1q, and IGM proteins were induced in patients with DKD and were correlated with fibrosis and inflammation. Our study shows for the first time the potential activation of the complement cascade associated with inflammation-mediated kidney fibrosis in the Ins2Akita T1D mouse model. Our findings could provide new perspectives for the treatment of early DKD as well as support the use of Ins2Akita T1D in pre-clinical studies.

The nuclear factor kappa B signaling pathway is a master regulator of renal fibrosis

Renal fibrosis is increasingly recognized as a global public health problem. Acute kidney injury (AKI) and chronic kidney disease (CKD) both result in renal fibrosis. Oxidative stress and inflammation play central roles in progressive renal fibrosis. Oxidative stress and inflammation are closely linked and form a vicious cycle in which oxidative stress induces inflammation through various molecular mechanisms. Ample evidence has indicated that a hyperactive nuclear factor kappa B (NF-ƙB) signaling pathway plays a pivotal role in renal fibrosis. Hyperactive NF-ƙB causes the activation and recruitment of immune cells. Inflammation, in turn, triggers oxidative stress through the production of reactive oxygen species and nitrogen species by activating leukocytes and resident cells. These events mediate organ injury through apoptosis, necrosis, and fibrosis. Therefore, developing a strategy to target the NF-ƙB signaling pathway is important for the effective treatment of renal fibrosis. This Review summarizes the effect of the NF-ƙB signaling pathway on renal fibrosis in the context of AKI and CKD (immunoglobulin A nephropathy, membranous nephropathy, diabetic nephropathy, hypertensive nephropathy, and kidney transplantation). Therapies targeting the NF-ƙB signaling pathway, including natural products, are also discussed. In addition, NF-ƙB-dependent non-coding RNAs are involved in renal inflammation and fibrosis and are crucial targets in the development of effective treatments for kidney disease. This Review provides a clear pathophysiological rationale and specific concept-driven therapeutic strategy for the treatment of renal fibrosis by targeting the NF-ƙB signaling pathway.

Special Issue IJMS-Molecular Mechanisms of Diabetic Kidney Disease

Diabetic kidney disease (DKD), as a major microvascular complication of both type 1 and type 2 diabetes mellitus (DM), accounts for over 40% of patients that reach end-stage renal disease and are referred to renal replacement therapies [...].

Crosstalk between proximal tubular epithelial cells and other interstitial cells in tubulointerstitial fibrosis after renal injury

The energy needs of tubular epithelial components, especially proximal tubular epithelial cells (PTECs), are high and they heavily depend on aerobic metabolism. As a result, they are particularly vulnerable to various injuries caused by factors such as ischemia, proteinuria, toxins, and elevated glucose levels. Initial metabolic and phenotypic changes in PTECs after injury are likely an attempt at survival and repair. Nevertheless, in cases of recurrent or prolonged injury, PTECs have the potential to undergo a transition to a secretory state, leading to the generation and discharge of diverse bioactive substances, including transforming growth factor-β, Wnt ligands, hepatocyte growth factor, interleukin (IL)-1β, lactic acid, exosomes, and extracellular vesicles. By promoting fibroblast activation, macrophage recruitment, and endothelial cell loss, these bioactive compounds stimulate communication between epithelial cells and other interstitial cells, ultimately worsening renal damage. This review provides a summary of the latest findings on bioactive compounds that facilitate the communication between these cellular categories, ultimately leading to the advancement of tubulointerstitial fibrosis (TIF).

Effects of conditioned media derived from human Wharton's jelly mesenchymal stem cells on diabetic nephropathy and hepatopathy via modulating TGF-β and apelin signaling pathways in male rats

BACKGROUND

Diabetic nephropathy and hepatopathy are health problems described by specific renal and hepatic structure and function disturbances. The protective effects of the stem cell secretome have been shown in several kidney and liver diseases. The current study aims to evaluate the capability of conditioned media derived from human Wharton's jelly mesenchymal stem cells (hWJ-MSCs-CM) to alleviate diabetic complications.

METHODS

Twenty Sprague Dawley rats were made diabetic through injection of STZ (60 mg/kg, i.p.). At week 8, diabetic rats were divided into two groups: treated [DM + hWJ-MSCs-CM (500 µl/rat for three weeks, i.p.)] and not treated (DM). At the 11th week, three groups (control, DM, and DM + hWJ-MSCs-CM) were kept in metabolic cages, and urine was collected for 24 h. The serum samples were maintained for measuring fasting blood glucose (FBG) and kidney and liver functional analysis. The left kidney and liver parts were kept at -80 °C to assess apelin and transforming growth factor-beta (TGF-β) expression. The right kidney, pancreas, and liver parts were used for histopathologic evaluation.

RESULTS

DM was detected by higher FBG, microalbuminuria, increased albumin/creatinine ratio, and pancreas, renal, and hepatic structural disturbances. Diabetic hepatopathy was determined by increasing liver enzymes and decreasing total bilirubin. The TGF-β gene expression was significantly upregulated in the diabetic kidney and liver tissues. Apelin gene expression was significantly downregulated in the diabetic liver tissue but did not change in kidney tissue. Administration of hWJ-MSCs-CM improved renal and hepatic functional and structural disturbances. Moreover, CM therapy significantly decreased TGF-β expression and enhanced apelin expression in the kidney and liver tissues.

CONCLUSION

Human WJ-MSCs-CM may have protective effects on diabetic renal and hepatic complications. These effects may happen through the regulation of TGF-β and apelin signaling pathways.

Progress and application of adipose-derived stem cells in the treatment of diabetes and its complications

Diabetes mellitus (DM) is a serious chronic metabolic disease that can lead to many serious complications, such as cardiovascular disease, retinopathy, neuropathy, and kidney disease. Once diagnosed with diabetes, patients need to take oral hypoglycemic drugs or use insulin to control blood sugar and slow down the progression of the disease. This has a significant impact on the daily life of patients, requiring constant monitoring of the side effects of medication. It also imposes a heavy financial burden on individuals, their families, and even society as a whole. Adipose-derived stem cells (ADSCs) have recently become an emerging therapeutic modality for DM and its complications. ADSCs can improve insulin sensitivity and enhance insulin secretion through various pathways, thereby alleviating diabetes and its complications. Additionally, ADSCs can promote tissue regeneration, inhibit inflammatory reactions, and reduce tissue damage and cell apoptosis. The potential mechanisms of ADSC therapy for DM and its complications are numerous, and its extensive regenerative and differentiation ability, as well as its role in regulating the immune system and metabolic function, make it a powerful tool in the treatment of DM. Although this technology is still in the early stages, many studies have already proven its safety and effectiveness, providing new treatment options for patients with DM or its complications. Although based on current research, ADSCs have achieved some results in animal experiments and clinical trials for the treatment of DM, further clinical trials are still needed before they can be applied in a clinical setting.

High sensitivity C-reactive protein and prediabetes progression and regression in middle-aged and older adults: A prospective cohort study

BACKGROUND

This study aimed to investigate the effect of systemic inflammation, assessed by high sensitivity C-reactive protein (hs-CRP) levels, on prediabetes progression and regression in middle-aged and older adults based on the China Health and Retirement Longitudinal Study (CHARLS).

METHODS

Participants with prediabetes from CHARLS were followed up 4 years later with blood samples collected for measuring fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c). The level of hs-CRP was assessed at baseline and categorized into tertiles (low, middle, and high groups). Prediabetes at baseline and follow-up was defined primarily according to the American Diabetes Association (ADA) criteria. Logistic regression models were used to estimate the odds ratios (ORs) and confidence intervals (CIs). We also performed stratified analyses according to age, gender, BMI, the presence of hypertension, and the disease history of heart disease and dyslipidemia and sensitivity analyses excluding a subset of participants with incomplete data.

RESULTS

Of the 2,874 prediabetes included at baseline, 834 participants remained as having prediabetes, 146 progressed to diabetes, and 1,894 regressed to normoglycemia based on ADA criteria with a 4 year follow-up. After multivariate logistics regression analysis, prediabetes with middle (0.67-1.62 mg/L) and high (>1.62 mg/L) hs-CRP levels had an increased incidence of progressing to diabetes compared with prediabetes with low hs-CRP levels (<0.67 mg/L; OR = 1.846, 95%CI: 1.129-3.018; and OR = 1.632, 95%CI: 0.985-2.703, respectively), and the incidence of regressing to normoglycemia decreased (OR = 0.793, 95%CI: 0.645-0.975; and OR = 0.769, 95%CI: 0.623-0.978, respectively). Stratified analyses and sensitivity analyses showed consistent results.

CONCLUSIONS

Low levels of hs-CRP are associated with a high incidence of regression from prediabetes to normoglycemia and reduced odds of progression to diabetes.

Human placenta-derived mesenchymal stem cells ameliorate diabetic kidney disease by modulating the T helper 17 cell/ regulatory T-cell balance through the programmed death 1 / programmed death-ligand 1 pathway

AIM

To investigate the therapeutic effects and immunomodulatory mechanisms of human placenta-derived mesenchymal stem cells (PMSCs) in diabetic kidney disease (DKD).

METHODS

Streptozotocin-induced DKD rats were administered an equivalent volume of saline or PMSCs (1 × 106 in 2 mL phosphate-buffered saline per rat) for 3 weeks. Eight weeks after treatment, we examined the biochemical parameters in the blood and urine, the ratio of T helper 17 cells (Th17) and regulatory T cells (Treg) in the blood, cytokine levels in the kidney and blood, and renal histopathological changes. In addition, we performed PMSC tracing and renal transcriptomic analyses using RNA-sequencing. Finally, we determined whether PMSCs modulated the Th17/Treg balance by upregulating programmed death 1 (PD-1) in vitro.

RESULTS

The PMSCs significantly improved renal function, which was assessed by serum creatinine levels, urea nitrogen, cystatin C levels, urinary albumin-creatinine ratio, and the kidney index. Further, PMSCs alleviated pathological changes, including tubular vacuolar degeneration, mesangial matrix expansion, and glomerular filtration barrier injury. In the DKD rats in our study, PMSCs were mainly recruited to immune organs, rather than to the kidney or pancreas. PMSCs markedly promoted the Th17/Treg balance and reduced the levels of pro-inflammatory cytokines (interleukin [IL]-17A and IL-1β) in the kidney and blood of DKD rats. In vitro experiments showed that PMSCs significantly reduced the proportion of Th17 cells and increased the proportion of Treg cells by upregulating PD-1 in a cell-cell contact manner and downregulating programmed death-ligand 1 (PD-L1) expression in PMSCs, which reversed the Th17/Treg balance.

CONCLUSION

We found that PMSCs improved renal function and pathological damage in DKD rats and modulated Th17/Treg balance through the PD-1/PD-L1 pathway. These findings provide a novel mechanism and basis for the clinical use of PMSCs in the treatment of DKD.

Incretin Therapies for Patients with Type 2 Diabetes and Chronic Kidney Disease

Since the early 2000s, an influx of novel glucose-lowering agents has changed the therapeutic landscape for treatment of diabetes and diabetes-related complications. Glucagon-like peptide-1 (GLP-1) receptor agonists represent an important therapeutic class for the management of type 2 diabetes (T2D), demonstrating benefits beyond glycemic control, including lowering of blood pressure and body weight, and importantly, decreased risk of development of new or worsening chronic kidney disease (CKD) and reduced rates of atherosclerotic cardiovascular events. Plausible non-glycemic mechanisms that benefit the heart and kidneys with GLP-1 receptor agonists include anti-inflammatory and antioxidant effects. Further supporting their use in CKD, the glycemic benefits of GLP-1 receptor agonists are preserved in moderate-to-severe CKD. Considering current evidence, major guideline-forming organizations recommend the use of GLP-1 receptor agonists in cases of T2D and CKD, especially in those with obesity and/or in those with high cardiovascular risk or established heart disease. Evidence continues to build that supports benefits to the heart and kidneys of the dual GLP-1/glucose-dependent insulinotropic polypeptide (GIP) receptor agonist tirzepatide. Ongoing outcome and mechanistic studies will continue to inform our understanding of the role of GLP-1 and dual GLP-1/GIP receptor agonists in diverse patient populations with kidney disease.

Chronic Kidney Disease Interplay with Comorbidities and Carbohydrate Metabolism: A Review

Chronic kidney disease (CKD) poses a global health challenge, engendering various physiological and metabolic shifts that significantly impact health and escalate the susceptibility to severe illnesses. This comprehensive review delves into the intricate complexities of CKD, scrutinizing its influence on cellular growth homeostasis, hormonal equilibrium, wasting, malnutrition, and its interconnectedness with inflammation, oxidative stress, and cardiovascular diseases. Exploring the genetic, birth-related, and comorbidity factors associated with CKD, alongside considerations of metabolic disturbances, anemia, and malnutrition, the review elucidates how CKD orchestrates cellular growth control. A pivotal focus lies on the nexus between CKD and insulin resistance, where debates persist regarding its chronological relationship with impaired kidney function. The prevalence of insulin abnormalities in CKD is emphasized, contributing to glucose intolerance and raising questions about its role as a precursor or consequence. Moreover, the review sheds light on disruptions in the growth hormone and insulin-like growth factor axis in CKD, underscoring the heightened vulnerability to illness and mortality in cases of severe growth retardation. Wasting, a prevalent concern affecting up to 75% of end-stage renal disease (ESRD) patients, is analyzed, elucidating the manifestations of cachexia and its impact on appetite, energy expenditure, and protein reserves. Taste disturbances in CKD, affecting sour, umami, and salty tastes, are explored for their implications on food palatability and nutritional status. Independent of age and gender, these taste alterations have the potential to sway dietary choices, further complicating the management of CKD. The intricate interplay between CKD, inflammation, oxidative stress, and cardiovascular diseases is unraveled, emphasizing the profound repercussions on overall health. Additionally, the review extends its analysis to CKD's broader impact on cognitive function, emotional well-being, taste perception, and endothelial dysfunction. Concluding with an emphasis on dietary interventions as crucial components in CKD management, this comprehensive review navigates the multifaceted dimensions of CKD, providing a nuanced understanding essential for developing targeted therapeutic strategies.

Anti-VEGFR2 F(ab')2 drug conjugate promotes renal accumulation and glomerular repair in diabetic nephropathy

Poor renal distribution of antibody-based drugs is the key factor contributing to low treatment efficiency for renal diseases and side effects. Here, we prepare F(ab')2 fragmented vascular endothelial growth factor receptor 2 antibody (anti-VEGFR2 (F(ab')2) to block VEGFR2 overactivation in diabetic nephropathy (DN). We find that the anti-VEGFR2 F(ab')2 has a higher accumulation in DN male mice kidneys than the intact VEGFR2 antibody, and simultaneously preserves the binding ability to VEGFR2. Furthermore, we develop an antibody fragment drug conjugate, anti-VEGFR2 F(ab')2-SS31, comprising the anti-VEGFR2 F(ab')2 fragment linked to the mitochondria-targeted antioxidant peptide SS31. We find that introduction of SS31 potentiates the efficacy of anti-VEGFR2 F(ab')2. These findings provide proof of concept for the premise that antibody fragment drug conjugate improves renal distribution and merits drug validation in renal disease therapy.

Targeted drug delivery strategy: a bridge to the therapy of diabetic kidney disease

Diabetic kidney disease (DKD) is the main complication in diabetes mellitus (DM) and the main cause of end-stage kidney disease worldwide. However, sodium glucose cotransporter 2 (SGLT2) inhibition, glucagon-like peptide-1 (GLP-1) receptor agonist, mineralocorticoid receptor antagonists and endothelin receptor A inhibition have yielded promising effects in DKD, a great part of patients inevitably continue to progress to uremia. Newly effective therapeutic options are urgently needed to postpone DKD progression. Recently, accumulating evidence suggests that targeted drug delivery strategies, such as macromolecular carriers, nanoparticles, liposomes and so on, can enhance the drug efficacy and reduce the undesired side effects, which will be a milestone treatment in the management of DKD. The aim of this article is to summarize the current knowledge of targeted drug delivery strategies and select the optimal renal targeting strategy to provide new therapies for DKD.

Logic-Based Modeling of Inflammatory Macrophage Crosstalk with Glomerular Endothelial Cells in Diabetic Kidney Disease

Diabetic kidney disease is a complication in 1 out of 3 patients with diabetes. Aberrant glucose metabolism in diabetes leads to an immune response causing inflammation and to structural and functional damage in the glomerular cells of the kidney. Complex cellular signaling lies at the core of metabolic and functional derangement. Unfortunately, the mechanism underlying the role of inflammation in glomerular endothelial cell dysfunction during diabetic kidney disease is not fully understood. Computational models in systems biology allow the integration of experimental evidence and cellular signaling networks to understand mechanisms involved in disease progression. We built a logic-based ordinary differential equations model to study macrophage-dependent inflammation in glomerular endothelial cells during diabetic kidney disease progression. We studied the crosstalk between macrophages and glomerular endothelial cells in the kidney using a protein signaling network stimulated with glucose and lipopolysaccharide. The network and model were built using the open-source software package Netflux. This modeling approach overcomes the complexity of studying network models and the need for extensive mechanistic details. The model simulations were fitted and validated against available biochemical data from in vitro experiments. The model identified mechanisms responsible for dysregulated signaling in macrophages and glomerular endothelial cells during diabetic kidney disease. In addition, we investigated the influence of signaling interactions and species that on glomerular endothelial cell morphology through selective knockdown and downregulation. We found that partial knockdown of VEGF receptor 1, PLC-γ, adherens junction proteins, and calcium partially recovered the endothelial cell fenestration size. Our model findings contribute to understanding signaling and molecular perturbations that affect the glomerular endothelial cells in the early stage of diabetic kidney disease.

Soluble tumor necrosis factor receptor type 1 predicts cardiorenal outcomes and better associated with distinct cardiovascular or renal outcomes than precedential renal or cardiovascular events in type 2 diabetes mellitus

Background

Inflammations are the crucial pathogenesis of chronic complications of type 2 diabetes mellitus (T2DM).

Objectives

The timeline of cardiovascular and renal complications of T2DM and whether soluble tumor necrosis factor receptor type 1 (sTNFR1) levels predict cardiorenal outcomes were still elusive.

Design

Prospectively observational study.

Methods

Chinese patients with T2DM were enrolled. Cardiorenal composite events defined by either cardiovascular composite events (all-cause mortality, acute coronary syndrome, or non-fatal stroke) or renal composite events (a decline of >30% of renal function or worsening status of albuminuria) were followed. Associations of sTNFR1 levels and cardiovascular, renal, and cardiorenal composite events were analyzed in regression models presented by hazard ratio (HR) and 95% confidence interval (95% CI).

Results

Among 370 subjects, 42 cardiovascular and 86 renal composite events occurred. Higher sTNFR1 levels were related to higher frequency and risks of cardiovascular composite events (HR 1.07, 95% CI 1.01-1.13, p = 0.009) and renal composite events (HR 1.05, 95% CI 1.02-1.09, p < 0.001). Occurrences of cardiovascular composite events were not predicted by precedential renal composite events. sTNFR1 levels were proved to be associated with risks of cardiorenal composite events in Cox regression sequential models (adjusted HR 1.04, 95% CI 1.00-1.08, p = 0.03). The results were consistent in all subgroup analyses.

Conclusion

Levels of sTNFR1 were associated with cardiorenal complications of T2DM and the predictabilities of TNFR1 levels were better than precedential cardiovascular or renal events.