Model Of Kidney Disease Research Articles

Recent advances in extracellular matrix manipulation for kidney organoid research

The kidney plays a crucial role in maintaining the body’s microenvironment homeostasis. However, current treatment options and therapeutic agents for chronic kidney disease (CKD) are limited. Fortunately, the advent of kidney organoids has introduced a novel in vitro model for studying kidney diseases and drug screening. Despite significant efforts has been leveraged to mimic the spatial-temporal dynamics of fetal renal development in various types of kidney organoids, there is still a discrepancy in cell types and maturity compared to native kidney tissue. The extracellular matrix (ECM) plays a crucial role in regulating cellular signaling, which ultimately affects cell fate decision. As a result, ECM can refine the microenvironment of organoids, promoting their efficient differentiation and maturation. This review examines the existing techniques for culturing kidney organoids, evaluates the strengths and weaknesses of various types of kidney organoids, and assesses the advancements and limitations associated with the utilization of the ECM in kidney organoid culture. Additionally, it presents a discussion on constructing specific physiological and pathological microenvironments using decellularized extracellular matrix during certain developmental stages or disease occurrences, aiding the development of kidney organoids and disease models.

ASK-1 activation exacerbates kidney dysfunction via increment of glomerular permeability and accelerates cellular aging in diabetic kidney disease model mice

Diabetic kidney disease (DKD) is a major disease characterized by early albuminuria and heightened risk of renal deterioration. Increased reactive oxygen species (ROS) production, especially in glomeruli, plays an important role in the progression of DKD. ROS also cause activation of Apoptosis signal-regulating kinase 1 (ASK-1), which is implicated in various organ injuries. However, the detailed mechanisms remain unclear. This study investigates ASK-1 activation in advanced DKD and its underlying mechanisms using GS442172, an ASK-1 inhibitor. In the DKD mouse model, activation of ASK-1 was observed. Although inhibition of ASK-1 activation improved hyperpermeability in glomerular endothelial cells. ASK-1 inhibition significantly reduced glomerular injury and albuminuria, while also attenuating tubular damage and interstitial fibrosis. RNA-seq analysis revealed an aging phenotype associated with ASK-1 activation in DKD. In vitro experiments demonstrated ASK-1 activation-induced cellular senescence in tubular cells via redox signaling. These results suggested that the critical role of ASK-1 activation in DKD pathogenesis, implicating glomerular injury, tubular damage, and cellular senescence. ASK-1 inhibitors are promising therapeutic strategies to mitigate the progression of DKD.

DOT1L protects against podocyte injury in diabetic kidney disease through phospholipase C-like 1

BackgroundPodocyte injury causes proteinuria and accelerates glomerular sclerosis during diabetic kidney disease (DKD). Disruptor of telomeric silencing 1-like (DOT1L), an evolutionarily conserved histone methyltransferase, has been reported in preventing kidney fibrosis in chronic kidney disease models. However, whether DOT1L exerts beneficial effects in diabetes induced podocyte injury and the underlying molecular mechanisms need further exploration.MethodsThe expression of DOT1L was confirmed by Western blotting in MPC-5 cells and cortex of kidney from db/db mice, as well as immunofluorescence staining in human renal biopsy samples. The effect of DOT1L on podocyte injury was obtained using MPC-5 cells and db/db mice. The potential target genes regulated by DOT1L was measured by RNA-sequencing. Then, a series of molecular biological experiments was performed to investigate the regulation of PLCL1 by DOT1L in MCP-5 cells and db/db mice. Lipid accumulation was assessed by UPLC-MS/MS analysis and Oil Red O staining.ResultsDOT1L expression was significantly declined in high glucose (HG)-treated MPC-5 cells, podocyte regions of kidney tissues from db/db mice and human renal biopsy samples. Subsequent investigations revealed that upregulation of DOT1L ameliorated HG-induced cell apoptosis in MPC-5 cells as well as primary podocytes. Furthermore, podocyte-specific DOT1L overexpression inhibited diabetic podocyte injury in db/db mice. Mechanistically, we revealed that DOT1L upregulated phospholipase C-like 1 (PLCL1) expression by mediating H3K79me2 at its promoter and PLCL1 silencing suppressed the protective role of DOT1L on podocyte injury. Moreover, DOT1L improved diabetes induced abnormal fatty acid metabolism in podocytes and PLCL1 knockdown reversed its protective effects.ConclusionsTaken together, our results indicate that DOT1L protects podocyte injury via PLCL1-mediated fatty acid metabolism and provides new insights into the therapeutic target of DKD.

Integrin alpha1 beta1 promotes interstitial fibrosis in a mouse model of polycystic kidney disease.

Fibrosis is the cause of end-stage kidney failure in patients with Autosomal Dominant Polycystic Kidney Disease (ADPKD). The molecular and cellular mechanisms involved in fibrosis are complex and anti-fibrotic therapies have so far failed to make an impact on patient welfare. Using unbiased proteomics analysis on the Pkd1 nl/nl mouse, we found that expression of the integrin α1 subunit is increased in this model of ADPKD. In human ADPKD tissue and two single cell RNA kidney disease datasets, ITGA1 was also upregulated. To investigate the functional role of this integrin subunit in ADPKD, we generated a Pkd1 nl/nl Itga1 -/- mouse. We observed a significant reduction in kidney volume and kidney dysfunction in mice lacking the integrin α1 subunit. Kidneys from Pkd1 nl/nl Itga1 -/- mice had smaller cysts and reduced interstitial expansion and tubular atrophy. Picrosirius red staining identified a restriction in collagen staining in the interstitium and the myofibroblast marker α smooth muscle actin was also downregulated. Myofibroblast cell proliferation was reduced in Pkd1 nl/nl Itga1 -/- mice and primary fibroblast cultures demonstrated an abrogated fibrogenic phenotype in integrin α1-depleted fibroblasts. These results highlight a previously unrecognised role for the integrin α1 subunit in kidney fibrosis.

Comparison of sGC activator and sGC stimulator in 5/6 nephrectomized rats on high-salt-diet.

Soluble guanylate cyclase (sGC) stimulators and activators are known to enhance kidney function in various models of chronic kidney disease (CKD) by increasing cyclic guanosine monophosphate (cGMP). Their differential effects on CKD progression, particularly under conditions of oxidative stress, remain unexplored by direct comparative studies. We conducted a side-by-side comparison using 5/6 nephrectomized rats on a high salt diet (5/6Nx+HSD) to evaluate the efficacy of the sGC stimulator BAY 41-8543 and the sGC activator BAY 60-2770 in CKD progression. BAY 41-8543 (1mg/kg; twice daily) and BAY 60-2770 (1mg/kg; once daily) were administered by gavage for 11 weeks. The 5/6Nx+HSD model led to increased plasma creatinine, proteinuria, and blood pressure. Both BAY 41-8543 and BAY 60-2770 significantly reduced systolic and diastolic blood pressure to a similar extent but did not improve renal function parameters. Notably, BAY 60-2770 reduced renal fibrosis, including interstitial fibrosis and glomerulosclerosis, whereas BAY 41-8543 did not. These antifibrotic effects of BAY 60-2770 were independent of blood pressure reduction. Proteomic analysis revealed that BAY 60-2770 corrected the upregulation of 9 proteins associated with apoptosis and fibrosis, including Caspase-3, MKK6 (Mitogen-Activated Protein Kinase Kinase 6), Prdx5 (Peroxiredoxin-5), in the 5/6Nx+HSD group. In contrast, BAY 41-8543 had no significant impact on these proteins. sGC activators were more effective than sGC stimulators in reducing renal fibrosis in 5/6 nephrectomized rats on a high salt diet, and this effect was due to modulation of apoptosis-associated proteins beyond the control of blood pressure.

Mechanosensitive Differentiation of Human iPS Cell-Derived Podocytes.

Stem cell fate decisions, including proliferation, differentiation, morphological changes, and viability, are impacted by microenvironmental cues such as physical and biochemical signals. However, the specific impact of matrix elasticity on kidney cell development and function remains less understood due to the lack of models that can closely recapitulate human kidney biology. An established protocol to differentiate podocytes from human-induced pluripotent stem (iPS) cells provides a promising avenue to elucidate the role of matrix elasticity in kidney tissue development and lineage determination. In this study, we synthesized polyacrylamide hydrogels with different stiffnesses and investigated their ability to promote podocyte differentiation and biomolecular characteristics. We found that 3 kPa and 10 kPa hydrogels significantly support the adhesion, differentiation, and viability of podocytes. Differentiating podocytes on a more compliant (0.7 kPa) hydrogel resulted in significant cell loss and detachment. Further investigation of the mechanosensitive proteins yes-associated protein (YAP) and synaptopodin revealed nuanced molecular distinctions in cellular responses to matrix elasticity that may otherwise be overlooked if morphology and cell spreading alone were used as the primary metric for selecting matrices for podocyte differentiation. Specifically, hydrogels with kidney-like rigidities outperformed traditional tissue culture plates at modulating the molecular-level expression of active mechanosensitive proteins critical for podocyte health and function. These findings could guide the development of physiologically relevant platforms for kidney tissue engineering, disease modeling, and mechanistic studies of organ physiology and pathophysiology. Such advances are critical for realizing the full potential of in vitro platforms in accurately predicting human biological responses.

Development of a prediction model for the incidence of type 2 diabetic kidney disease and its application based on a regional health data platform

Objective: To construct a risk prediction model for diabetes kidney disease (DKD). Methods: Patients newly diagnosed with type 2 diabetes mellitus (T2DM) between January 1, 2015, and December 31, 2022, were selected as study subjects from the Yinzhou Regional Health Information Platform in Ningbo City. The Lasso method was used to screen the risk factors, and the DKD risk prediction model was established using Cox proportional hazard regression models. Bootstrap 500 resampling was applied for internal validation. Results: The study included 49 706 subjects, with an median (Q1, Q3) age of 60.00 (50.00, 68.00) years old, and 55% were male. A total of 4 405 subjects eventually developed DKD. Age at first diagnosis of T2DM, BMI, education level, fasting plasma glucose, glycated hemoglobin A1c, urinary albumin, past medical history (hyperuricemia, rheumatic diseases), triglycerides, and estimated glomerular filtration rate were included in the final model. The final model's C-index was 0.653, with an average of 0.654 after Bootstrap correction. The final model's area under the receiver operating characteristic curve for predicting 4-year, 5-year, and 6-year was 0.657, 0.659, and 0.664, respectively. The calibration curve was closely aligned with the ideal curve. Conclusions: This study constructed a DKD risk prediction model for newly diagnosed T2DM patients based on real-world data that is simple, easy to use, and highly practical. It provides a reliable basis for screening high-risk groups for DKD.

Changes in Skeletal Muscle Atrophy over Time in a Rat Model of Adenine-Induced Chronic Kidney Disease

This study evaluated changes over time in skeletal muscle atrophy, expressions of skeletal muscle anabolic and catabolic genes, and mitochondrial activity by skeletal muscle type in an adenine-induced chronic kidney disease (CKD) model. A CKD model was successfully established by feeding male Wistar rats a 0.75% adenine diet for 4 weeks starting at 8 weeks of age. Control and CKD groups were sacrificed at 12 and 20 weeks of age. The back muscles were analyzed histologically, and succinate dehydrogenase (SDH) staining was performed to evaluate mitochondrial activity. Gene expressions of myogenic determination gene number 1 and myogenin as indicators of muscle anabolism, atrogin-1 and muscle RING-finger protein-1 (MuRF1) as indicators of muscle catabolism, and peroxisome proliferator-activated receptor-γ coactivator-1-α as a marker of mitochondrial biogenesis were assessed. Type I and type II muscle cross-sectional areas (CSAs) were decreased at 12 weeks, but type I muscle CSA was recovered at 20 weeks. SDH staining was lower in CKD than in control rats at 12 weeks, but no significant difference was observed at 20 weeks. Increased expressions of myogenin, atrogin-1, and MuRF-1 were observed only at 12 weeks, but no differences were observed at 20 weeks. The adenine-induced CKD rat model appears to show changes in muscle atrophy over time.

Engineering of Kidney-Targeting Fluorophores with Tunable Emission from NIR-I to NIR-II for Early Diagnosis of Kidney Disease.

The development of rapidly distributed and retained probes within the kidneys is important for accurately diagnosing kidney diseases. Although molecular imaging shows the potential for non-intrusively interrogating kidney disease-related biomarkers, the limited kidney contrast of many fluorophores, owing to their relatively low distribution in the kidney, hinders their effectiveness for kidney disease detection. Herein, for the first time, an amino-functionalization strategy is proposed to construct a library of kidney-targeting fluorophores NHcy with tunable emissions from NIR-I to NIR-II. Among these, NHcy-8 is the first small-molecule NIR-II dye without a renal clearance moiety, designed specifically for kidney-targeting imaging. Building on this class of NIR-II fluorophore, the first NIR-II small-molecule kidney-targeting pH probe NIR-II-pH is developed, which exhibits a desirable kidney distribution after intravenous injection and is fluorescent only after activation by acidosis. NIR-II in vivo fluorescence/photoacoustic imaging of kidney disease models induced by cisplatin and renal I/R injury using NIR-II-pH reveals increasingly severe metabolic acidosis as the disease progressed, enabling sensitive detection of the onset of acidosis 36h (cisplatin group) earlier than clinical methods. Thus, this study introduces a practical NIR-II kidney-targeting probe and provides a useful molecular blueprint for guiding kidney-targeting NIR-II fluorophores as diagnostic aids for kidney diseases.

Renal nerves in physiology, pathophysiology and interoception.

Sympathetic efferent renal nerves have key roles in the regulation of kidney function and blood pressure. Increased renal sympathetic nerve activity is thought to contribute to hypertension by promoting renal sodium retention, renin release and renal vasoconstriction. This hypothesis led to the development of catheter-based renal denervation (RDN) for the treatment of hypertension. Two RDN devices that ablate both efferent and afferent renal nerves received FDA approval for this indication in 2023. However, in animal models, selective ablation of afferent renal nerves resulted in comparable anti-hypertensive effects to ablation of efferent and afferent renal nerves and was associated with a reduction in sympathetic nerve activity. Selective afferent RDN also improved kidney function in a chronic kidney disease model. Notably, the beneficial effects of RDN extend beyond hypertension and chronic kidney disease to other clinical conditions that are associated with elevated sympathetic nerve activity, including heart failure and arrhythmia. These findings suggest that the kidney is an interoceptive organ, as increased renal sensory nerve activity modulates sympathetic activity to other organs. Future studies are needed to translate this knowledge into novel therapies for the treatment of hypertension and other cardiorenal diseases.

Indoxyl Sulfate as Potential Kidney Tubular Function Marker across Kidney Disease Models

Indoxyl Sulfate as Potential Kidney Tubular Function Marker across Kidney Disease Models

Total alkaloids of Aconitum carmichaelii Debx alleviate cisplatin-induced acute renal injury by inhibiting inflammation and oxidative stress related to gut microbiota metabolism

BackgroundCisplatin-induced acute kidney injury (AKI) is a complex and serious clinical issue, representing a major cause of hospital-acquired AKI. Alkaloids are the main active constituents of Aconitum carmichaelii Debx, which exhibit protective effects in several kidney disease models and against other acute organ injuries. However, its activity and mechanism of action in AKI treatment remain unclear. PurposeThis study aimed to elucidate the effect of Aconitum carmichaelii Debx (ACA) in a model of cisplain-induced AKI and comprehensively investigate its underlying mechanisms. MethodsThe major alkaloids in ACA were analyzed using high-performance liquid chromatography. Blood urea nitrogen (BUN) and serum creatine levels were measured using automated biochemical instruments. 16S rRNA sequencing, short-chain fatty acid (SCFA) analysis, fecal microbiota transplantation (FMT), non-targeted metabolomics, and transcriptomics were performed to systematically identify prospective biomarkers after ACA treatment. Anti-inflammatory and anti-oxidative stress activities were monitored using ELISA and western blotting. ResultsFour main compounds (fuziline, neoline, talatisamine, and songorine) were identified in ACA. ACA significantly alleviated cisplatin-induced AKI by reducing (BUN) and serum creatine levels and improving histopathological scores. Moreover, ACA balanced cisplatin-mediated confoundments in microbial composition and function, including decreasing the levels of Escherichia-Shigella, Clostridium, and Ruminococcus, as well as increasing Ligilactobacillus, Anaerotruncus, Bacteroides and Desulfovibrio levels, accompanied by uremic toxin reduction, and augmenting serum SCFAs. The FMT experiments further confirmed that ACA exerts anti-AKI effects by affecting gut microbiota. A multi-omics study has shown that ACA regulates glutathione and tryptophan metabolism and mediates pathways that trigger inflammatory responses. Finally, ACA reduced serum levels of inflammatory factors (IL-1β, IL-6, and TNF-α), restored enzymes of the antioxidative system (SOD and CAT) and GSH values, and decreased monoester diterpene alkaloid levels in the kidney by inhibiting the expression of NF-κB pathway-related proteins and increasing Nrf2/HO-1 pathway-related protein expression. ConclusionACA protects against cisplatin-induced AKI through its anti-inflammatory and antioxidant functions, which may be associated with the restoration of gut microbiota metabolism. ACA is a potential drug for AKI and other forms of organ damage related to the disruption of the gut microbiota.

Associations between Renin-Angiotensin System and Abnormal Renal Energy Metabolism in a Mouse Model of Diabetic Kidney Disease

Associations between Renin-Angiotensin System and Abnormal Renal Energy Metabolism in a Mouse Model of Diabetic Kidney Disease

Loss of ARL13B's Guanine Nucleotide Exchange Factor Activity for ARL3 in Cilia Suppresses Cystogenesis in Adult Mouse Models of Polycystic Kidney Disease

Loss of ARL13B's Guanine Nucleotide Exchange Factor Activity for ARL3 in Cilia Suppresses Cystogenesis in Adult Mouse Models of Polycystic Kidney Disease

Adeno-Associated Virus 1 (AAV1) CFTR Gene Therapy Successfully Reduces Cysts in a Mouse Model of Autosomal Dominant Polycystic Kidney Disease

Adeno-Associated Virus 1 (AAV1) CFTR Gene Therapy Successfully Reduces Cysts in a Mouse Model of Autosomal Dominant Polycystic Kidney Disease

Curcumin and its combination with a reduced dose of rosuvastatin: A promising therapy for chronic kidney disease and associated dyslipidemia in rat animal models.

The objective of this study was to confirm the effects of curcumin and to investigate the effects of its combination with a reduced dose of rosuvastatin in an adenine-induced model of chronic kidney disease (CKD) and associated dyslipidemia in rats. Renal function and morphology, as well as lipid status, were assessed using laboratory parameters and histopathological analysis. Male Wistar rats (n=36) randomly divided into six groups, were treated for 24 days: normal control (standard diet), CKD control (adenine diet, 0.75% w/w adenine-supplemented diet), curcumin (100 mg/kg/day + adenine diet), rosuvastatin minimal therapeutic dose (MTD) (5 mg/day + adenine diet), rosuvastatin reduced dose (RD, 25% of rosuvastatin MTD + adenine diet), and rosuvastatin RD + curcumin (25% of rosuvastatin MTD + curcumin 100 mg/kg/day + adenine diet) group. While rosuvastatin alone showed only antilipemic action, both curcumin alone and its combination with a reduced dose of rosuvastatin showed better renal protection with lower serum creatinine levels and milder renal morphological alterations, as well as better antilipemic action with lower levels of triglycerides, very low-density lipoprotein (VLDL), and low-density lipoprotein (LDL) cholesterols compared with the levels in CKD control rats. Treatment with curcumin alone also resulted in a significantly higher estimated glomerular filtration rate, lower uric acid levels, and higher high-density lipoprotein (HDL) cholesterol, while the combined therapy additionally resulted in higher serum albumin levels, lower total cholesterol, and both atherogenic and coronary risk indexes compared with CKD control rats. The results of this study confirmed the beneficial effects of curcumin alone and provided new evidence for the beneficial effects of its combination with a reduced dose of rosuvastatin in rats with CKD and associated dyslipidemia.

Early Treatment with 2-Deoxy-D-Glucose Reduces Proliferative Proteins in the Kidney and Slows Cyst Growth in a Hypomorphic Pkd1 Mouse Model of Autosomal Dominant Polycystic Kidney Disease

Early Treatment with 2-Deoxy-D-Glucose Reduces Proliferative Proteins in the Kidney and Slows Cyst Growth in a Hypomorphic Pkd1 Mouse Model of Autosomal Dominant Polycystic Kidney Disease

Deletion of the Homeobox Gene Cux1 Decreases Ciliogenesis in a Mouse Model of Polycystic Kidney Disease

Deletion of the Homeobox Gene Cux1 Decreases Ciliogenesis in a Mouse Model of Polycystic Kidney Disease

Modulation of Kidney Disorders in Type 2 Diabetes: Evaluating the Role of Probiotics in a Rat Model of Diabetic Kidney Disease

Modulation of Kidney Disorders in Type 2 Diabetes: Evaluating the Role of Probiotics in a Rat Model of Diabetic Kidney Disease

A Ketogenic Diet Alters Liver Cyst Progression in a Rodent Model of Polycystic Kidney Disease and Is Dependent on GPR109A

A Ketogenic Diet Alters Liver Cyst Progression in a Rodent Model of Polycystic Kidney Disease and Is Dependent on GPR109A