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Renal Failure Dec 2023Artemisinin has immunomodulatory, anti-inflammatory, and antifibrotic effects. Some studies have demonstrated that artemisinins have a protective effect on the kidney....
Artemisinin has immunomodulatory, anti-inflammatory, and antifibrotic effects. Some studies have demonstrated that artemisinins have a protective effect on the kidney. DHA is a derivative of artemisinin and has effects similar to those of artemisinin. Human bone marrow-derived mesenchymal stem cells (BMSCs) accelerate renal repair following acute injury. In the study, we investigated the effects of combination therapy with DHA and BMSCs on membranous nephropathy (MN) mice. The 24-h urinary protein, serum total cholesterol (TC) and triglyceride (TG) levels, and renal histopathology, were measured to evaluate kidney damage. Anti-PLA2R, IgG, and complement 3 (C3) were detected by ELISA. The expression levels of the podocyte injury-related proteins were analyzed by immunohistochemistry. The protein expression levels of -SMA, ED-1, TGF-1, p-Smad2, and p-Smad3 were detected by western blot to analyze renal fibrosis and its regulatory mechanism. Results showed that combination therapy with DHA and BMSCs significantly ameliorated kidney damage in MN model mice by decreasing the levels of 24 h urinary protein, TC and TG. This combination therapy also improved renal histology and reduced the expression of IgG and C3 in the glomerulus. In addition, this combination therapy decreased the expression of podocin and nephrin and relieved renal fibrosis by downregulating -SMA and ED-1. Furthermore, this combination therapy suppressed TGF-1 expression and Smad2/3 phosphorylation. This result (i.e., this combination therapy inhibited the TGF-1/Smad pathway) was also supported . Taken together, combination therapy with DHA and BMSCs ameliorated podocyte injury and renal fibrosis in MN mice by downregulating the TGF1/Smad pathway.
Topics: Mice; Humans; Animals; Transforming Growth Factor beta1; Glomerulonephritis, Membranous; Podocytes; Kidney Diseases; Fibrosis; Immunoglobulin G; Smad Proteins
PubMed: 36648018
DOI: 10.1080/0886022X.2022.2120821 -
Physiological Reports Jan 2023Podocytes are terminally differentiated epithelial cells in glomeruli. Podocyte injury and loss are features of many diseases leading to chronic kidney disease (CKD)....
Podocytes are terminally differentiated epithelial cells in glomeruli. Podocyte injury and loss are features of many diseases leading to chronic kidney disease (CKD). The developmental origins of health and disease hypothesis propose an adverse intrauterine environment can lead to CKD later in life, especially when a second postnatal challenge is experienced. The aim of this study was to examine whether a suboptimal maternal environment would result in reduced podocyte endowment, increasing susceptibility to diabetes-induced renal injury. Female C57BL/6 mice were fed a low protein diet (LPD) to induce growth restriction or a normal protein diet (NPD) from 3 weeks before mating until weaning (postnatal Day 21, P21) when nephron and podocyte endowment were assessed in one male and one female offspring per litter. Littermates were administered streptozotocin or vehicle at 6 weeks of age. Urinary albumin excretion, glomerular size, and podometrics were assessed following 18 weeks of hyperglycemia. LPD offspring were growth restricted and had lower nephron and podocyte number at P21. However, by 24 weeks the podocyte deficit was no longer evident and despite low nephron endowment neither albuminuria nor glomerulosclerosis were observed. Podocyte number was unaffected by 18 weeks of hyperglycemia in NPD and LPD offspring. Diabetes increased glomerular volume reducing podocyte density, with more pronounced effects in LPD offspring. LPD and NPD diabetic offspring developed mild albuminuria with LPD demonstrating an earlier onset. LPD offspring also developed glomerular pathology. These findings indicate that growth-restricted LPD offspring with low nephron number and normalized podocyte endowment were more susceptible to alterations in glomerular volume and podocyte density leading to more rapid onset of albuminuria and renal injury than NPD offspring.
Topics: Mice; Animals; Male; Female; Podocytes; Albuminuria; Mice, Inbred C57BL; Diabetes Mellitus; Hyperglycemia; Renal Insufficiency, Chronic
PubMed: 36695822
DOI: 10.14814/phy2.15579 -
Kidney360 Mar 2022Diseases of the glomeruli, the renal filtration units, are a leading cause of progressive kidney disease. Assessment of the ultrastructure of podocytes at the glomerular...
BACKGROUND
Diseases of the glomeruli, the renal filtration units, are a leading cause of progressive kidney disease. Assessment of the ultrastructure of podocytes at the glomerular filtration barrier is essential for diagnosing diverse disease entities, providing insight into the disease pathogenesis, and monitoring treatment responses.
METHODS
Here we apply previously published sample preparation methods together with stimulated emission depletion and confocal microscopy for resolving nanoscale podocyte substructure. The protocols are modified and optimized in order to be applied to formalin-fixed paraffin-embedded (FFPE) samples.
RESULTS
We successfully modified our protocols to allow for deep three-dimensional stimulated emission depletion and confocal imaging of FFPE kidney tissue with similar staining and image quality compared with our previous approaches. We further show that quantitative analysis can be applied to extract morphometrics from healthy and diseased samples from both mice and humans.
CONCLUSIONS
The results from this study could increase the feasibility of implementing optical kidney imaging protocols in clinical routines because FFPE is the gold-standard method for storage of patient samples.
Topics: Animals; Glomerular Filtration Barrier; Humans; Kidney; Mice; Microscopy, Confocal; Paraffin Embedding; Podocytes
PubMed: 35582181
DOI: 10.34067/KID.0005882021 -
The Journal of Clinical Investigation Dec 2023Profilin1 belongs to a family of small monomeric actin-binding proteins with diverse roles in fundamental actin-dependent cellular processes required for cell survival....
Profilin1 belongs to a family of small monomeric actin-binding proteins with diverse roles in fundamental actin-dependent cellular processes required for cell survival. Podocytes are postmitotic visceral epithelial cells critical for the structure and function of the kidney filtration barrier. There is emerging evidence that the actin-related mode of cell death known as mitotic catastrophe is an important pathway involved in podocyte loss. In this issue of the JCI, Tian, Pedigo, and colleagues demonstrate that profilin1 deficiency in podocytes triggered cell cycle reentry, resulting in abortive cytokinesis with a loss in ribosomal RNA processing that leads to podocyte loss and glomerulosclerosis. This study demonstrates the essential role of actin dynamics in mediating this fundamental mode of podocyte cell death.
Topics: Humans; Podocytes; Actins; Kidney Diseases; Cell Cycle; Cell Death
PubMed: 38099501
DOI: 10.1172/JCI175594 -
Archives of Endocrinology and Metabolism Jun 2023The incidence of diabetic nephropathy (DN) is gradually increasing worldwide. Podocyte injury, such as podocyte apoptosis and loss of the slit diaphragm (SD)-specific...
OBJECTIVE
The incidence of diabetic nephropathy (DN) is gradually increasing worldwide. Podocyte injury, such as podocyte apoptosis and loss of the slit diaphragm (SD)-specific markers are early pathogenic features of DN.
MATERIALS AND METHODS
The cultured mouse podocytes were separated into a high glucose-treated (HG, 30mM) group to mimic DN , a low glucose-treated (LG, 5mM) group as a control and HG+ angiotensin-(1-7)(Ang-(1-7)) and HG+Ang-(1-7) + D-Ala7-Ang-(1-7) (A779, Ang-(1-7)/Mas receptor antagonist) experimental groups. The Cell Counting Kit-8 (CCK-8) method and flow cytometry was used to detect podocyte activity and podocyte apoptosis respectively. The expression of angiotensin type 1 receptor (AT1R), Mas receptor (MasR) and podocyte-specific markers were examined by q-PCR and Western blot, respectively.
RESULTS
The results showed that the decrease in podocyte activity; the increase in podocyte apoptosis; the decreased mRNA and protein expression of nephrin, podocin, WT-1 and MasR; and the upregulated expression of AT1R induced by HG could be reversed by Ang-(1-7). However, these effects were blocked by A779. The possible mechanisms of the Ang-(1-7)-mediated effect depended on MasR. In addition, the protective effect of Ang-(1-7) on podocyte activity was dose-dependent and most obvious at 10 µM. A779 had the greatest antagonistic action against Ang-(1-7) at a concentration of 10 μM.
CONCLUSION
This study reveals that binding of Ang-(1-7) to its specific receptor MasR may counteract the effects of Ang II mediated by AT1R to significantly attenuate podocyte injury induced by high glucose. Ang-(1-7)/MasR targeting in podocytes may be a therapeutic approach to attenuate renal injury in DN.
Topics: Animals; Mice; Angiotensin II; Diabetic Nephropathies; Glucose; Podocytes
PubMed: 37364145
DOI: 10.20945/2359-3997000000643 -
International Journal of Molecular... Feb 2023The use of mesenchymal stem cells (MSCs) has become a new strategy for treating diabetic kidney disease (DKD). However, the role of placenta derived mesenchymal stem...
The use of mesenchymal stem cells (MSCs) has become a new strategy for treating diabetic kidney disease (DKD). However, the role of placenta derived mesenchymal stem cells (P-MSCs) in DKD remains unclear. This study aims to investigate the therapeutic application and molecular mechanism of P-MSCs on DKD from the perspective of podocyte injury and PINK1/Parkin-mediated mitophagy at the animal, cellular, and molecular levels. Western blotting, reverse transcription polymerase chain reaction, immunofluorescence, and immunohistochemistry were used to detect the expression of podocyte injury-related markers and mitophagy-related markers, SIRT1, PGC-1α, and TFAM. Knockdown, overexpression, and rescue experiments were performed to verify the underlying mechanism of P-MSCs in DKD. Mitochondrial function was detected by flow cytometry. The structure of autophagosomes and mitochondria were observed by electron microscopy. Furthermore, we constructed a streptozotocin-induced DKD rat model and injected P-MSCs into DKD rats. Results showed that as compared with the control group, exposing podocytes to high-glucose conditions aggravated podocyte injury, represented by a decreased expression of Podocin along with increased expression of Desmin, and inhibited PINK1/Parkin-mediated mitophagy, manifested as a decreased expression of Beclin1, the LC3II/LC3I ratio, Parkin, and PINK1 associated with an increased expression of P62. Importantly, these indicators were reversed by P-MSCs. In addition, P-MSCs protected the structure and function of autophagosomes and mitochondria. P-MSCs increased mitochondrial membrane potential and ATP content and decreased the accumulation of reactive oxygen species. Mechanistically, P-MSCs alleviated podocyte injury and mitophagy inhibition by enhancing the expression of the SIRT1-PGC-1α-TFAM pathway. Finally, we injected P-MSCs into streptozotocin-induced DKD rats. The results revealed that the application of P-MSCs largely reversed the markers related to podocyte injury and mitophagy and significantly increased the expression of SIRT1, PGC-1α, and TFAM compared with the DKD group. In conclusion, P-MSCs ameliorated podocyte injury and PINK1/Parkin-mediated mitophagy inhibition in DKD by activating the SIRT1-PGC-1α-TFAM pathway.
Topics: Animals; Female; Pregnancy; Rats; Diabetic Nephropathies; Mesenchymal Stem Cells; Mitophagy; Placenta; Podocytes; Protein Kinases; Sirtuin 1; Streptozocin; Transcription Factors; Ubiquitin-Protein Ligases
PubMed: 36902127
DOI: 10.3390/ijms24054696 -
Advanced Science (Weinheim,... Mar 2024Podocytes are particularly sensitive to lipid accumulation, which has recently emerged as a crucial pathological process in the progression of proteinuric kidney...
Podocytes are particularly sensitive to lipid accumulation, which has recently emerged as a crucial pathological process in the progression of proteinuric kidney diseases like diabetic kidney disease and focal segmental glomerulosclerosis. However, the underlying mechanism remains unclear. Here, podocytes predominantly expressed protein dedicator of cytokinesis 5 (Dock5) is screened to be critically related to podocyte lipid lipotoxicity. Its expression is reduced in both proteinuric kidney disease patients and mouse models. Podocyte-specific deficiency of Dock5 exacerbated podocyte injury and glomeruli pathology in proteinuric kidney disease, which is mainly through modulating fatty acid uptake by the liver X receptor α (LXRα)/scavenger receptor class B (CD36) signaling pathway. Specifically, Dock5 deficiency enhanced CD36-mediated fatty acid uptake of podocytes via upregulating LXRα in an m A-dependent way. Moreover, the rescue of Dock5 expression ameliorated podocyte injury and proteinuric kidney disease. Thus, the findings suggest that Dock5 deficiency is a critical contributor to podocyte lipotoxicity and may serve as a promising therapeutic target in proteinuric kidney diseases.
Topics: Mice; Animals; Humans; Podocytes; Lipid Metabolism; Kidney Diseases; Fatty Acids; Lipids; Guanine Nucleotide Exchange Factors
PubMed: 38161229
DOI: 10.1002/advs.202306365 -
Journal of Nanobiotechnology Oct 2023Primary nephrotic syndrome (PNS) is characterized by edema, heavy proteinuria, hypoalbuminemia and hyperlipidemia. Moreover, podocyte injury is the key pathological...
BACKGROUND
Primary nephrotic syndrome (PNS) is characterized by edema, heavy proteinuria, hypoalbuminemia and hyperlipidemia. Moreover, podocyte injury is the key pathological change of PNS. Even though the pathophysiological etiology of PNS has not been fully understood, the production of excessive reactive oxygen species (ROS) plays an important role in the development and progression of the disease. Glucocorticoids are the first-line medications for patients with PNS, but their clinical use is hampered by dose-dependent side effects. Herein, we accelerated the rate of conversion from Ce to Ce by doping Zr in ceria-zirconia nanomedicines to treat the PNS rat model by removal of ROS.
RESULTS
The engineered CeZrO (7CZ) nanomedicines significantly improved the ROS scavenging ability of podocytes at a very low dose, enabling effective inhibition of podocyte apoptosis and actin cytoskeleton depolymerization induced by adriamycin (ADR). Accordingly, podocyte injury was effectively alleviated in rat models of ADR-induced nephrotic syndrome, as confirmed by serum tests and renal tissue staining. Moreover, the mRNA sequencing assay revealed the protective molecular signaling pathways of 7CZ nanomedicines in podocytes.
CONCLUSION
7CZ nanomedicines were highly effective in protecting against ADR-induced podocyte injury in vitro and in vivo at a very low concentration.
Topics: Humans; Rats; Animals; Nephrotic Syndrome; Doxorubicin; Podocytes; Antioxidants; Reactive Oxygen Species; Nanomedicine
PubMed: 37858242
DOI: 10.1186/s12951-023-02136-2 -
Journal of the American Society of... Aug 2021CKD is associated with the loss of functional nephr ons, leading to increased mechanical and metabolic stress in the remaining cells, particularly for cells constituting...
BACKGROUND
CKD is associated with the loss of functional nephr ons, leading to increased mechanical and metabolic stress in the remaining cells, particularly for cells constituting the filtration barrier, such as podocytes. The failure of podocytes to mount an adequate stress response can lead to further nephron loss and disease progression. However, the mechanisms that regulate this degenerative process in the kidney are unknown.
METHODS
We combined , and organ-on-chip approaches to identify the RE1-silencing transcription factor (REST), a repressor of neuronal genes during embryonic development, as a central regulator of podocyte adaptation to injury and aging.
RESULTS
Mice with a specific deletion of in podocytes exhibit albuminuria, podocyte apoptosis, and glomerulosclerosis during aging, and exhibit increased vulnerability to renal injury. This phenotype is mediated, in part, by the effects of REST on the podocyte cytoskeleton that promote resistance to mechanical stressors and augment podocyte survival. Finally, REST expression is upregulated in human podocytes during aging, consistent with a conserved mechanism of stress resistance.
CONCLUSIONS
These results suggest REST protects the kidney from injury and degeneration during aging, with potentially important therapeutic implications.
Topics: Adaptation, Physiological; Adult; Aged; Aged, 80 and over; Aging; Albuminuria; Animals; Apoptosis; Cell Line; Cell Survival; Cytoskeleton; Gene Expression Regulation; Homeostasis; Humans; Mice; Phenotype; Podocytes; Repressor Proteins; Sclerosis; Stress, Physiological; Young Adult
PubMed: 34078664
DOI: 10.1681/ASN.2021020231 -
Experimental Cell Research Sep 2020Podocytes are actin-rich epithelial cells whose effacement and detachment are the main cause of glomerular disease. Crk family proteins: Crk1/2 and CrkL are reported to...
Podocytes are actin-rich epithelial cells whose effacement and detachment are the main cause of glomerular disease. Crk family proteins: Crk1/2 and CrkL are reported to be important intracellular signaling proteins that are involved in many biological processes. However, the roles of them in maintaining podocyte morphology and function remain poorly understood. In this study, specific knocking down of Crk1/2 and CrkL in podocytes caused abnormal cell morphology, actin cytoskeleton rearrangement and dysfunction in cell adhesion, spreading, migration, and viability. The p130Cas, focal adhesion kinase, phosphatidylinositol 3-kinase/Akt, p38 and JNK signaling pathways involved in these alterations. Furthermore, knocking down CrkL alone conferred a more modest phenotype than did the Crk1/2 knockdown and the double knockdown. Kidney biopsy specimens from patients with focal segmental glomerulosclerosis and minimal change nephropathy showed downregulation of Crk1/2 and CrkL in glomeruli. In zebrafish embryos, Crk1/2 and CrkL knockdown compromised the morphology and caused abnormal glomerular development. Thus, our results suggest that Crk1/2 and CrkL expression are important in podocytes; loss of either will cause podocyte dysfunction, leading to foot process effacement and podocyte detachment.
Topics: Actin Cytoskeleton; Adaptor Proteins, Signal Transducing; Focal Adhesion Protein-Tyrosine Kinases; Glomerulosclerosis, Focal Segmental; Humans; Kidney Diseases; Kidney Glomerulus; Phosphatidylinositol 3-Kinase; Podocytes; Proto-Oncogene Proteins c-crk
PubMed: 32535035
DOI: 10.1016/j.yexcr.2020.112135