Mechanisms In Diabetic Kidney Disease Research Articles

Leech granules inhibit ferroptosis and alleviate renal injury in mice with diabetic kidney disease

Ethnopharmacological relevanceThe underlying mechanisms of diabetic kidney disease (DKD) and effective treatment strategies remain unclear. DKD progression is closely associated with abnormal iron metabolism and ferroptosis in vivo. Leeches, used in traditional Chinese medicine for promoting blood circulation and resolving blood stasis, are utilized to treat diabetes and its associated complications. Leeches effectively antagonize oxidative stress injury and exert protective effects on renal function. However, whether leeches can inhibit ferroptosis by modulating oxidative stress and iron metabolism remains unclear. Aim of the studyTo investigate the therapeutic potential of leech granules in DKD and, specifically, their effects on ferroptosis. Materials and methodsWe used a mouse model of DKD. The mice were treated with leech granules via gavage. Component identification and analysis of leech granules were performed using UPLC-MS, and efficacy was assessed by histopathology and analysis of blood glucose, lipids, and renal function. Additionally, the pharmacological mechanisms of leech granules were explored via proteomics, immunohistochemical staining, western blotting, and cell culture. ResultsProteomic analysis showed that iron metabolism was dysregulated and ferroptosis increased in DKD mice. Leech granules significantly reduced iron accumulation and renal pathological damage, decreased ROS levels, upregulated GSH levels, and inhibited ferroptosis in the kidneys of DKD mice. Furthermore, in vitro cellular experiments demonstrated that leech granules could inhibit erastin-induced ferroptosis and protect renal cells. ConclusionsThe regulation of renal iron metabolism and inhibition of ferroptosis mediates the therapeutic effect of leech granules on DKD. Leech granules represent a promising approach for DKD treatment.

RBBP6-Mediated ERRα Degradation Contributes to Mitochondrial Injury in Renal Tubular Cells in Diabetic Kidney Disease.

Diabetic Kidney Disease (DKD), a major precursor to end-stage renal disease, involves mitochondrial dysfunction in proximal renal tubular cells (PTCs), contributing to its pathogenesis. Estrogen-related receptor α (ERRα) is essential for mitochondrial integrity in PTCs, yet its regulation in DKD is poorly understood. This study investigates ERRα expression and its regulatory mechanisms in DKD, assessing its therapeutic potential. Using genetic, biochemical, and cellular approaches, ERRα expression Was examined in human DKD specimens and DKD mouse models. We identified the E3 ubiquitin ligase retinoblastoma binding protein 6 (RBBP6) as a regulator of ERRα, promoting its degradation through K48-linked polyubiquitination at the K100 residue. This degradation pathway significantly contributed to mitochondrial injury in PTCs of DKD models. Notably, conditional ERRα overexpression or RBBP6 inhibition markedly reduced mitochondrial damage in diabetic mice, highlighting ERRα's protective role in maintaining mitochondrial integrity. The interaction between RBBP6 and ERRα opens new therapeutic avenues, suggesting that modulating RBBP6-ERRα interactions could be a strategy for preserving mitochondrial function and slowing DKD progression.

Gender-associated features in diabetic kidney disease

Diabetic kidney disease (DKD) is the leading cause of end-stage renal failure. Evidence indicates gender differences in the progression of this disease. This study aimed to determine gender differences in prevalence and identify gender-associated risk factors contributing to the development of diabetic kidney disease in individuals with type 2 diabetes mellitus (T2DM). The cross-sectional study included 132 patients with T2DM ranging in age from 50 to 65 years. Subjects were stratified by sex (80 women and 52 men). Gender differences have been studied in relation to the incidence and prevalence of DKD, their phenotypes and clinical manifestations, and several risk factors that have different effects on both sexes. The outcome of clinical kidney function assessment showed that 70% subjects were diagnosed with DKD (71% of women and 67% of men). The study indicated an association between the duration of T2DM and urinary albumin levels, as well as between arterial hypertension and triglyceride levels, which are independent risk factors for DKD development. Notably, older women with T2DM have a higher prevalence of DKD than older men. The albuminuric component of DKD was more frequently observed in men. Additionally, men were more likely to have adverse risk factors, including dyslipidemia, lower high-density lipoprotein cholesterol, and glomerular filtration rate, which are factors involved in the mechanisms of DKD. In summary, the results indicate that: 1) women with type 2 diabetes mellitus are at a higher risk of developing a normoalbuminuric phenotype of diabetic kidney disease, while men are at a higher risk of developing an albuminuric phenotype of diabetic kidney disease leading to renal failure and end-stage renal disease; 2) gender differences are most noticeable among older adults and may have significant implications for the development of more effective diagnostic and treatment methods for diabetic kidney disease, tailored to individual needs.

Single-Nucleus RNA Sequencing Reveals Sex-Specific Renoprotective Mechanisms in Diabetic Kidney Disease

Single-Nucleus RNA Sequencing Reveals Sex-Specific Renoprotective Mechanisms in Diabetic Kidney Disease

Acteoside protects podocyte against apoptosis through regulating AKT/GSK-3β signaling pathway in db/db mice

BackgroundPodocyte apoptosis is one of the important pathological mechanisms of diabetic kidney disease (DKD). Acteoside (Act), a major active component of Rehmannia glutinosa leaves total glycoside, has a strong renoprotective action. Our study aims to demonstrate Act’s renoprotective actions in db/db mice.MethodsWe adopted C57BLKS/J db/db mice as DKD animal models. After 8 weeks of Act administration, the 24-hour urine albumin, renal function index, and blood lipid levels were quantified using matching kits. Renal pathology was evaluated by HE and PAS staining. The podocyte damage and apoptosis-related signaling pathway were observed by using immunohistochemistry, western blot, and TUNEL staining.ResultsThe albuminuria of db/db mice was reduced from 391 ug/24 h to 152 ug/24 h, and renal pathology changes were alleviated after Act administration. The western blot and immunohistochemistry showed that Act treatment upregulated the synaptopodin and podocin expression compared with db/db mice, while the TUNEL staining indicated podocyte apoptosis was inhibited. The B-cell lymphoma-2 (Bcl-2) level was upregulated in the Act group, but cleaved caspase-3 and Bcl-2 associated X protein (Bax) expression declined, while the protein kinase B/glycogen synthase kinase-3β (AKT/GSK-3β) signaling pathway was repressed.ConclusionsBy inhibiting the AKT/GSK-3β signaling pathway, Act protected podocytes from apoptosis, decreasing the urine albumin of db/db mice and delaying the course of DKD.

Metabolic Differences in Diabetic Kidney Disease Patients with Normoalbuminuria versus Moderately Increased Albuminuria.

The pathophysiological mechanisms of diabetic kidney disease with normal versus moderately increased albuminuria (NA-DKD and A-DKD) are currently not well understood and could have implications for diagnosis and treatment. 14 NA-DKD patients with urine albumin/creatinine ratio <3mg/mmol, 26 A-DKD patients with albumin/creatinine ratio 3-29mg/mmol, and 60 age- and sex-matched healthy controls were randomly chosen from a population-based cohort study (HUNT-3, Norway). 74 organic acids, 21 amino acids, 21 biogenic acids, 40 acylcarnitines, 14 sphingomyelins, and 88 phosphatidylcholines were quantified in urine. 146 diabetic patients from the US-based CRIC study were used to verify main findings. NA-DKD and A-DKD had similar age, kidney function, diabetes treatment and other traditional risk factors. Still, partial least-square discriminant analysis (PLS-DA) showed strong metabolite-based separation (R2 0.82, Q2 0.52) with NA-DKD positioned between healthy controls and A-DKD patients. 75 metabolites contributed significantly to separation between NA-DKD and A-DKD (VIP scores ≥1.0) with propionyl-carnitine (c3), phosphatidylcholine C38:4, medium-chained (C8) fatty acid octenedioic acid, and lactic acid as top metabolites (VIP scores 2.7-2.2). Compared to NA-DKD, A-DKD had higher short-chained acylcarnitines, higher long-chained fatty acids with more double-bounds, higher branched-chain amino acids, and lower TCA-cycle intermediates. Main findings were similar by random-forest analysis and in the CRIC cohort. Formal enrichment analysis indicated that fatty acid biosynthesis and oxydation, gluconeogenesis, TCA cycle, and glucose-alanine cycle were more disturbed in A-DKD patients compared to NA-DKD with identical eGFR. We also found indications of a Warburg-like effect in A-DKD, i.e., metabolism of glucose to lactate despite adequate oxygen. DKD patients with normo-albuminuria differ substantially in their metabolic disturbances compared to patients with moderately increase albuminuria and could represent different clinical phenotypes.

#4941 A METABOLOMIC FINGERPRINT PERSPECTIVE OF GUT-DERIVED METABOLITES ON EARLY DIABETIC KIDNEY DISEASE IN TYPE 2 DIABETES MELLITUS PATIENTS

Abstract Background and Aims Type 2 diabetes mellitus (T2DM) is the first cause of end stage renal disease worldwide. Metabolite profiling is an emerging field of great significance, as T2DM prevalence is continuously rising. The subtle dynamics of gut microbiota derived metabolites may have important implications in diabetic kidney disease (DKD) development. Nitrogen metabolic pathway and retinoic acid signaling pathway seem to be involved in early pathogenic mechanisms of DKD. The aim of study was to discover new putative gut-derived biomarkers that interfere with early physio-pathological mechanisms in DKD, regarding the podocyte, tubule, and the renal endothelium. Method The serum and urine of 90 T2DM patients (P group) and 20 healthy subjects (C group), were assessed in a cross-sectional study, by ultra-high-performance liquid chromatography coupled with electrospray ionization-quadrupole-time of flight-mass spectrometry (UHPLC-QTOF-ESI+-MS) techniques. P group was divided in 3 subgroups (normoalbuminuria-P1, microalbuminuria-P2, macroalbuminuria-P3). Statistical analysis was performed by untargeted multivariate (PLSDA, VIP scores, Random Forest, Biomarker analysis) and univariate (One Way ANOVA, Biomarker Analysis) methods. Results Multivariate analysis, by which the P group vs. C group were compared, displayed: (1) in serum samples: increased levels (P&amp;gt;C) of all-trans retinoic acid, cysteine-S sulfate, oleoylglicine, threonylglycine and decreased levels (P&amp;lt;C) of phenylalanine, tyrosine, kynurenic acid; (2) in urine samples, there were increased levels of: all-trans retinoic acid, indoxyl suflate, serotonin sulfate and glycylprolylarginine. Subsequently, by applying univariate analysis, the biomarkers derived from gut microbiota were selected: (1) in serum: all-trans retinoic acid (C&amp;lt;P1&amp;lt;P2&amp;lt;3), phenylalanine, tyrosine, and kynurenic acid with levels decreasing progressively from C to P1-P2-P3 (2) in urine: all trans retinoic acid, indoxyl sulfate, and serotonin sulfate, showing good differentiation between C and P1, and slight differences between P1∼P2∼P3 subgroups. The study suggests that ATRAs dynamic is disturbed in the normoalbuminuric stage of DKD. While its urinary levels correlated significantly with albuminuria, the changes observed in P1 subgroup, in serum and urine, may be correlated to the loss of renal tubular tight junction as a result of claudin downregulation. Phenylalanine and tyrosine, a part of nitrogen metabolic pathway, are indicators of the new-onset DKD. Their levels were upregulated in serum vs. urine, indicating their possible involvement in early DKD when comparing C vs. P1-P2-P3. Kynurenic acid and indoxyl-sulfate result from tryptophan metabolism. Low levels in serum of kynurenic acid may suggest its possible implication in incipient endothelial dysfunction in DKD. Indoxyl-sulfate (IS) urinary excretion is dependent on albuminuria. The study shows an elevated excretion of IS, in the normoalbuminuric group compared to controls and may suggest a tubular damage that precedes the glomerular modifications in DKD. Conclusion UHPLC-QTOF-ESI+-MS untargeted analysis reveals a particular metabolite fingerprint in early DKD. The study describes all-trans retinoic acid, phenylalanine, tyrosine, kynurenic acid, and indoxyl sulfate, as potential key biomarkers involved in early DKD pathogenesis, their levels being expressed in P1 subgroup compared with C group, and P2, P3 subgroups.

Investigate the genetic mechanisms of diabetic kidney disease complicated with inflammatory bowel disease through data mining and bioinformatic analysis.

Patients with diabetic kidney disease (DKD) often have gastrointestinal dysfunction such as inflammatory bowel disease (IBD). This study aims to investigate the genetic mechanism leading to IBD in DKD patients through data mining and bioinformatics analysis. The disease-related genes of DKD and IBD were searched from the five databases of OMIM, GeneCards, PharmGkb, TTD, and DrugBank, and the intersection part of the two diseases were taken to obtain the risk genes of DKD complicated with IBD. A protein-protein interaction (PPI) network analysis was performed on risk genes, and three topological parameters of degree, betweenness, and closeness of nodes in the network were used to identify key risk genes. Finally, Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed on the risk genes to explore the related mechanism of DKD merging IBD. This study identified 495 risk genes for DKD complicated with IBD. After constructing a protein-protein interaction network and screening for three times, six key risk genes were obtained, including matrix metalloproteinase 2 (MMP2), hepatocyte growth factor (HGF), fibroblast growth factor 2 (FGF2), interleukin (IL)-18, IL-13, and C-C motif chemokine ligand 5 (CCL5). Based on GO enrichment analysis, we found that DKD genes complicated with IBD were associated with 3,646 biological processes such as inflammatory response regulation, 121 cellular components such as cytoplasmic vesicles, and 276 molecular functions such as G-protein-coupled receptor binding. Based on KEGG enrichment analysis, we found that the risk genes of DKD combined with IBD were associated with 181 pathways, such as the PI3K-Akt signaling pathway, advanced glycation end product-receptor for AGE (AGE-RAGE) signaling pathway and hypoxia-inducible factor (HIF)-1 signaling pathway. There is a genetic mechanism for the complication of IBD in patients with CKD. Oxidative stress, chronic inflammatory response, and immune dysfunction were possible mechanisms for DKD complicated with IBD.

Identification of ferroptosis-related genes and pathways in diabetic kidney disease using bioinformatics analysis

Diabetic kidney disease (DKD) is a major public health issue because of its refractory nature. Ferroptosis is a newly coined programmed cell death characterized by the accumulation of lipid reactive oxygen species (ROS). However, the prognostic and diagnostic value of ferroptosis-related genes (FRGs) and their biological mechanisms in DKD remain elusive. The gene expression profiles GSE96804, GSE30566, GSE99339 and GSE30528 were obtained and analyzed. We constructed a reliable prognostic model for DKD consisting of eight FRGs (SKIL, RASA1, YTHDC2, SON, MRPL11, HSD17B14, DUSP1 and FOS). The receiver operating characteristic (ROC) curves showed that the ferroptosis-related model had predictive power with an area under the curve (AUC) of 0.818. Gene functional enrichment analysis showed significant differences between the DKD and normal groups, and ferroptosis played an important role in DKD. Consensus clustering analysis showed four different ferroptosis types, and the risk score of type four was significantly higher than that of other groups. Immune infiltration analysis indicated that the expression of macrophages M2 increased significantly, while that of neutrophils and mast cells activated decreased significantly in the high-risk group. Our study identified and validated the molecular mechanisms of ferroptosis in DKD. FRGs could serve as credible diagnostic biomarkers and therapeutic targets for DKD.

What's New in the Molecular Mechanisms of Diabetic Kidney Disease: Recent Advances.

Diabetic kidney disease (DKD) is the leading cause of chronic kidney disease, including end-stage kidney disease, and increases the risk of cardiovascular mortality. Although the treatment options for DKD, including angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, sodium-glucose cotransporter 2 inhibitors, and mineralocorticoid receptor antagonists, have advanced, their efficacy is still limited. Thus, a deeper understanding of the molecular mechanisms of DKD onset and progression is necessary for the development of new and innovative treatments for DKD. The complex pathogenesis of DKD includes various different pathways, and the mechanisms of DKD can be broadly classified into inflammatory, fibrotic, metabolic, and hemodynamic factors. Here, we summarize the recent findings in basic research, focusing on each factor and recent advances in the treatment of DKD. Collective evidence from basic and clinical research studies is helpful for understanding the definitive mechanisms of DKD and their regulatory systems. Further comprehensive exploration is warranted to advance our knowledge of the pathogenesis of DKD and establish novel treatments and preventive strategies.

Molecular Mechanisms of Diabetic Kidney Disease.

The inflammatory component of diabetic kidney disease has become of great interest in recent years, with genetic and epigenetic variants playing a fundamental role in the initiation and progression of the disease. Cells of the innate immune system play a major role in the pathogenesis of diabetic kidney disease, with a lesser contribution from the adaptive immune cells. Other components such as the complement system also play a role, as well as specific cytokines and chemokines. The inflammatory component of diabetic kidney disease is of great interest and is an active research field, with the hope to find potential innovative therapeutic targets.

Cellular Senescence and Regulated Cell Death of Tubular Epithelial Cells in Diabetic Kidney Disease.

Cellular senescence is frequently evident at etiologic sites of chronic diseases and involves essentially irreversible arrest of cell proliferation, increased protein production, resistance to apoptosis, and altered metabolic activity. Regulated cell death plays a vital role in shaping fully functional organs during the developmental process, coordinating adaptive or non-adaptive responses, and coping with long-term harmful intracellular or extracellular homeostasis disturbances. In recent years, the concept of ‘diabetic tubulopathy’ has emerged. tubular epithelial cells are particularly susceptible to the derangements of diabetic state because of the virtue of the high energy requirements and reliance on aerobic metabolism render. Hyperglycemia, oxidative stress, persistent chronic inflammation, glucose toxicity, advanced glycation end-products (AGEs) accumulation, lipid metabolism disorders, and lipotoxicity contribute to the cellular senescence and different patterns of regulated cell death (apoptosis, autophagic cell death, necroptosis, pyroptosis, and ferroptosis) in tubular epithelial cells. We now explore the ‘tubulocentric’ view of diabetic kidney disease(DKD). And we summarize recent discoveries regarding the development and regulatory mechanisms of cellular senescence, apoptosis, autophagic cell death, necroptosis, pyroptosis, and ferroptosis in the pathogenesis of DKD. These findings provide new perspectives on the mechanisms of DKD and are useful for designing novel therapeutic approaches for the treatment of DKD.

Puerarin attenuates diabetic kidney injury through interaction with Guanidine nucleotide-binding protein Gi subunit alpha-1 (Gnai1) subunit.

Radix puerariae, a traditional Chinese herbal medication, has been used to treat patients with diabetic kidney disease (DKD). Our previous studies demonstrated that puerarin, the active compound of radix puerariae, improves podocyte injury in type 1 DKD mice. However, the direct molecular target of puerarin and its underlying mechanisms in DKD remain unknown. In this study, we confirmed that puerarin also improved DKD in type 2 diabetic db/db mice. Through RNA‐sequencing odf isolated glomeruli, we found that differentially expressed genes (DEGs) that were altered in the glomeruli of these diabetic mice but reversed by puerarin treatment were involved mostly in oxidative stress, inflammatory and fibrosis. Further analysis of these reversed DEGs revealed protein kinase A (PKA) was among the top pathways. By utilizing the drug affinity responsive target stability method combined with mass spectrometry analysis, we identified guanine nucleotide‐binding protein Gi alpha‐1 (Gnai1) as the direct binding partner of puerarin. Gnai1 is an inhibitor of cAMP production which is known to have protection against podocyte injury. In vitro, we showed that puerarin not only interacted with Gnai1 but also increased cAMP production in human podocytes and mouse diabetic kidney in vivo. Puerarin also enhanced CREB phosphorylation, a downstream transcription factor of cAMP/PKA. Overexpression of CREB reduced high glucose‐induced podocyte apoptosis. Inhibition of PKA by Rp‐cAMP also diminished the effects of puerarin on high glucose‐induced podocyte apoptosis. We conclude that the renal protective effects of puerarin are likely through inhibiting Gnai1 to activate cAMP/PKA/CREB pathway in podocytes.

High-Throughput Metabolomics and Diabetic Kidney Disease Progression: Evidence from the Chronic Renal Insufficiency (CRIC) Study

Introduction: Metabolomics could offer novel prognostic biomarkers and elucidate mechanisms of diabetic kidney disease (DKD) progression. Via metabolomic analysis of urine samples from 995 CRIC participants with diabetes and state-of-the-art statistical modeling, we aimed to identify metabolites prognostic to DKD progression. Methods: Urine samples (N = 995) were assayed for relative metabolite abundance by untargeted flow-injection mass spectrometry, and stringent statistical criteria were used to eliminate noisy compounds, resulting in 698 annotated metabolite ions. Utilizing the 698 metabolites’ ion abundance along with clinical data (demographics, blood pressure, HbA1c, eGFR, and albuminuria), we developed univariate and multivariate models for the eGFR slope using penalized (lasso) and random forest models. Final models were tested on time-to-ESKD (end-stage kidney disease) via cross-validated C-statistics. We also conducted pathway enrichment analysis and a targeted analysis of a subset of metabolites. Results: Six eGFR slope models selected 9–30 variables. In the adjusted ESKD model with highest C-statistic, valine (or betaine) and 3-(4-methyl-3-pentenyl)thiophene were associated (p < 0.05) with 44% and 65% higher hazard of ESKD per doubling of metabolite abundance, respectively. Also, 13 (of 15) prognostic amino acids, including valine and betaine, were confirmed in the targeted analysis. Enrichment analysis revealed pathways implicated in kidney and cardiometabolic disease. Conclusions: Using the diverse CRIC sample, a high-throughput untargeted assay, followed by targeted analysis, and rigorous statistical analysis to reduce false discovery, we identified several novel metabolites implicated in DKD progression. If replicated in independent cohorts, our findings could inform risk stratification and treatment strategies for patients with DKD.

Identification of Key Candidate Genes and Chemical Perturbagens in Diabetic Kidney Disease Using Integrated Bioinformatics Analysis.

Globally, nearly 40 percent of all diabetic patients develop serious diabetic kidney disease (DKD). The identification of the potential early-stage biomarkers and elucidation of their underlying molecular mechanisms in DKD are required. In this study, we performed integrated bioinformatics analysis on the expression profiles GSE111154, GSE30528 and GSE30529 associated with early diabetic nephropathy (EDN), glomerular DKD (GDKD) and tubular DKD (TDKD), respectively. A total of 1,241, 318 and 280 differentially expressed genes (DEGs) were identified for GSE30258, GSE30529, and GSE111154 respectively. Subsequently, 280 upregulated and 27 downregulated DEGs shared between the three GSE datasets were identified. Further analysis of the gene expression levels conducted on the hub genes revealed SPARC (Secreted Protein Acidic And Cysteine Rich), POSTN (periostin), LUM (Lumican), KNG1 (Kininogen 1), FN1 (Fibronectin 1), VCAN (Versican) and PTPRO (Protein Tyrosine Phosphatase Receptor Type O) having potential roles in DKD progression. FN1, LUM and VCAN were identified as upregulated genes for GDKD whereas the downregulation of PTPRO was associated with all three diseases. Both POSTN and SPARC were identified as the overexpressed putative biomarkers whereas KNG1 was found as downregulated in TDKD. Additionally, we also identified two drugs, namely pidorubicine, a topoisomerase inhibitor (LINCS ID- BRD-K04548931) and Polo-like kinase inhibitor (LINCS ID- BRD-K41652870) having the validated role in reversing the differential gene expression patterns observed in the three GSE datasets used. Collectively, this study aids in the understanding of the molecular drivers, critical genes and pathways that underlie DKD initiation and progression.

MO635PRO-INFLAMMATORY CYTOKINES IL-6 AND IL-17 DISPLAY A PARTICULAR MOLECULAR PATTERN IN ASSOCIATION WITH DYSREGULATED MIRNAS IN PATIENTS WITH TYPE 2 DIABETES MELLITUS IN THE EARLY STAGES OF DIABETIC KIDNEY DISEASE

Abstract Background and Aims Glomerular injury and proximal tubule (PT) dysfunction have intricate mechanisms in diabetic kidney disease (DKD). Pro-inflammatory cytokines are involved in the initiation and progression of DKD through mediating the inflammatory response, both at glomerular and proximal tubular level. miRNAs are able to modulate cellular and biochemical functions, thus intervening in the pathogenesis of DKD. The aim of the study, performed on patients with type 2 diabetes mellitus (DM), was to evaluate selective pro-inflammatory cytokines in relation to biomarkers of podocyte lesion and of PT dysfunction. Particular molecular pathways, such as specific miRNA profiles operating in this relation, have also been studied. Method A number of 126 patients with type 2 DM, staged by albuminuria [39 normoalbuminuric – urinary albumin/creatinine ratio UACR)&amp;lt;30mg/g; 45 microalbuminuric–UACR-30–300mg/g; 42 macroalbuminuric–UACR&amp;gt;300mg/g], and 23 healthy control subjects were included in a cross-sectional study. All patients were evaluated concerning biomarkers of podocyte injury (nephrin, podocalyxin, synaptopodin) and of PT dysfunction [Kidney injury molecule-1(KIM-1), N-acetyl-beta-D-glucuronidase (NAG), alpha 1- microglobulin]. Also, serum and urinary levels of specific interleukins (IL-6, IL-17), serum cystatin C, and eGFR were determined. Serum and urinary miRNAs (miRNA-21, miRNA-124, miRNA-146a, miRNA-192) were assessed by RT-PCR. Results The biomarkers of podocyte lesion and of PT dysfunction were increased, even in normoalbuminuric type 2 DM patients. Serum and urinary IL-6 and IL-17 showed increased levels in type 2 DM patients, across all groups studied. The model provided by univariable regression analysis showed that IL-6 and IL-17 correlated directly with biomarkers of podocyte injury (nephrin, podocalyxin, synaptopodin), of PT dysfunction (KIM-1, NAG, alpha 1-microglobulin), as well as with UACR. Negative correlations have been identified regarding eGFR. In multivariable regression analysis, serum IL-6 correlated directly with synaptopodin, NAG, and negatively with eGFR (p&amp;lt;0.00001, R2=0.805); serum IL-17 correlated directly with synaptopodin, NAG, KIM-1, UACR, and negatively with eGFR (p&amp;lt;0.00001, R2=0.941); urinary IL-6 correlated directly with synaptopodin, NAG, and negatively with eGFR (p&amp;lt;0.00001, R2=0.889); urinary IL-17 correlated directly with synaptopodin, nephrin, NAG, and negatively with eGFR (p&amp;lt;0.00001, R2=0.905). Also, important associations were found between specific interleukins and miRNAs. In univariable regression analysis, IL-6 and IL-17 correlated directly with miRNA-21 and miRNA-124, and negatively with miRNA-146a and miRNA-192. The models provided by multivariable regression analysis showed that urinary IL-6 correlated directly with urinary miRNA-21, and negatively with urinary miRNA-192 (p&amp;lt;0.00001, R2=0.886). Urinary IL-17 displayed direct correlations with urinary miRNA-21, and negative correlations with urinary miRNA-192 (p&amp;lt;0.00001, R2=0.860). Serum IL-6 correlated directly with serum miRNA-21, miRNA-124, and indirectly with serum miRNA-146a, miRNA-192 (p&amp;lt;0.00001, R2=0.862). Serum IL-17 showed direct correlations with serum miRNA-21, miRNA-124, and negative correlations with serum miRNA-192 (p&amp;lt;0.00001, R2=0.745). Conclusion In the early stages of DKD, there is an association of pro-inflammatory cytokines with specific miRNAs, and with biomarkers of podocyte injury and of PT dysfunction. IL-6 and IL-17, as well as dysregulated miRNA-21, miRNA-124, miRNA-146a, and miRNA-192 display a particular molecular pattern, in relation to complex mechanisms that can initiate and maintain the chronic inflammatory response in DKD. Routine detection of these interleukins may provide biomarkers to refine the diagnosis of early renal involvement in the course of type 2 DM, independently of albuminuria and level of renal function.

Roles of Gut Microbial Metabolites in Diabetic Kidney Disease.

Diabetes is a highly prevalent metabolic disease that has emerged as a global challenge due to its increasing prevalence and lack of sustainable treatment. Diabetic kidney disease (DKD), which is one of the most frequent and severe microvascular complications of diabetes, is difficult to treat with contemporary glucose-lowering medications. The gut microbiota plays an important role in human health and disease, and its metabolites have both beneficial and harmful effects on vital physiological processes. In this review, we summarize the current findings regarding the role of gut microbial metabolites in the development and progression of DKD, which will help us better understand the possible mechanisms of DKD and explore potential therapeutic approaches for DKD.

Influence of exercise training on diabetic kidney disease: A brief physiological approach.

Diabetic kidney disease (DKD) is associated with increased mortality in diabetic patients and has a negative impact on public health. The identification of potential therapies that help the management of DKD can contribute to the improvement of health and quality of life of patients. Thus, this paper is timely and relevant because, in addition to presenting a concise review of the pathogenesis and major pathophysiological mechanisms of DKD, it addresses the most recent findings on the impact of exercise training on this disease. Thus, since non-pharmacological interventions have gained increasing attention in the fight against chronic diseases, this paper appears as an important tool to increase knowledge and stimulate innovative research on the impact of exercise on kidney disease.

Targeting oxidative stress and anti-oxidant defence in diabetic kidney disease.

There is an unmet need for new strategies to prevent or postpone the development of diabetic kidney disease. The pathophysiology of this condition includes as a central mechanism an imbalance between the excessive production of reactive oxygen species (ROS) and inadequate anti-oxidant defense. Reduction of ROS is therefore an interesting therapeutic target that warrants further investigation. Herein, we review the drivers of oxidative stress in diabetic kidney disease including NADPH oxidases, mitochondrial ROS production, xanthine oxidase, cytochrome P450, uncoupled eNOS and lipoxygenase. Secondly, the role of anti-oxidative mechanisms in diabetic kidney disease is discussed including the role of the kelch-like ECH-associated protein 1- nuclear factor erythroid 2-related factor 2, lipoxin, oral anti-oxidants and glutathione peroxidase-1. We will also review data supporting the concept that the beneficial renal effects of anti-diabetic drugs that target the glucagon-like peptide 1 receptor and the sodium glucose transporter 2 are, at least in part, due to their impact on oxidative stress in diabetic kidney disease. In the present article we critically evaluate both preclinical studies with cell culture experiments and animal models of diabetic kidney disease as well as covering the current findings from clinical studies addressing targeted interventions towards these pathways.

Pathophysiologic mechanisms in diabetic kidney disease: A focus on current and future therapeutic targets.

Diabetic kidney disease (DKD) is the primary cause of chronic kidney disease around the globe and is one of the main complications in patients with type 1 and 2 diabetes. The standard treatment for DKD is drugs controlling hyperglycemia and high blood pressure. Renin angiotensin aldosterone system blockade and sodium glucose cotransporter 2 (SGLT2) inhibition have yielded promising results in DKD, but many diabetic patients on such treatments nevertheless continue to develop DKD, leading to kidney failure and cardiovascular comorbidities. New therapeutic options are urgently required. We review here the promising therapeutic avenues based on insights into the mechanisms of DKD that have recently emerged, including mineralocorticoid receptor antagonists, SGLT2 inhibitors, glucagon-like peptide-1 receptor agonist, endothelin receptor A inhibition, anti-inflammatory agents, autophagy activators and epigenetic remodelling. The involvement of several molecular mechanisms in DKD pathogenesis, together with the genetic and epigenetic variability of this condition, makes it difficult to target this heterogeneous patient population with a single drug. Personalized medicine, taking into account the genetic and mechanistic variability, may therefore improve renal and cardiovascular protection in diabetic patients with DKD.