Podocytes Research Articles

Oxyfluorfen exposure can cause acute kidney injury by promoting ROS-induced oxidative stress and inflammation in zebrafish

Nephrotoxicity of oxyfluorfen to vertebrates remains unclear despite its wide use as a herbicide. In order to further study its nephrotoxicity and its underlying mechanism, we used human embryonic kidney cells and zebrafish to explore. HEK293T cells were exposed to 2, 4, 6 μg/mL oxyfluorfen for 24 h in vitro, and zebrafish were exposed to 0.4, 0.8, 1.2 mg/L oxyfluorfen for 72 h in vivo. We found that oxyfluorfen inhibits cell migration and induces oxidative stress and apoptosis, causing kidney damage or nephrotoxicity in embryonic and adult zebrafish. Oxyfluorfen triggered inflammation in zebrafish and causing severe periorbital and body edema in embryos. Oxyfluorfen induced the secretion of kidney injury markers, including urea nitrogen (BUN), creatinine (CR), and β-n-acetyl-glucosaminidase (NAG) in zebrafish. Additionally, oxyfluorfen affected the homeostasis of oxidant and antioxidant systems, leading to reactive oxygen species (ROS) overload. Oxyfluorfen also damaged the glomerular podocytes and induced apoptosis of proximal tubules, which is harmful to normal body function and the renal filtration system. These results indicate that oxyfluorfen is a potential environmental hazard that can cause severe kidney injury and affect the health of organisms.

Programmed Cell Death in Diabetic Nephropathy: A Review of Apoptosis, Autophagy, and Necroptosis.

Diabetic nephropathy is a common complication of type I and type II diabetes, in which renal glomeruli are destroyed, resulting in renal damage, proteinuria, and hypertension. Apoptosis, autophagy, and necroptosis are 3 forms of programmed cell death that have been implicated in the pathogenesis of diabetic nephropathy. Apoptosis of podocytes leads to glomerular injury and podocyte depletion, which are associated with proteinuria and glomerular structural damage in diabetic nephropathy. Additionally, epithelial cells in the proximal convoluted tubules also undergo apoptosis in diabetic nephropathy, leading to tubular atrophy, which causes tubular cell depletion and the subsequent formation of atubular glomeruli in association with the loss of renal function. On the other hand, insufficiency of autophagy has been correlated with the pathogenesis of diabetic nephropathy. For instance, decreased autophagic activity has been shown in podocytes of the diabetic kidney, causing variations in podocyte function and subsequent disruption to the glomerular filtration barrier. Furthermore, attenuated autophagic activity has also been demonstrated in proximal tubular cells of the diabetic kidney, resulting in the buildup of impaired molecules and organelles, which are normally broken down by autophagy, leading to proteinuria. Moreover, necroptosis might have a key role in podocyte damage and subsequent decline in diabetic nephropathy. Thus, this article aims to review the mechanisms and effects of programmed cell death in diabetic nephropathy, including the roles of apoptosis, autophagy, and necroptosis.

Hydrodynamic model for renal microvascular filtration: Effects of physiological and hemodynamic changes on glomerular size-selectivity.

The first step in renal urine formation is ultrafiltration across the glomerular barrier. The change in its nanostructure has been associated with nephrotic syndromes. Effects of physiological and hemodynamic factor alterations associated with diabetic nephropathy (DN) on glomerular permselectivity are examined through a mathematical model employing low-Reynolds-number hydrodynamics and hindered transport theory. Glomerular capillaries are represented as networks of cylindrical tubes with multilayered walls. Glomerular basement membrane (GBM) is a fibrous medium with bimodal fiber sizes. Epithelial slit fiber spacing follows a lognormal distribution based on reported electron micrographs with the highest resolution. Endothelial fenestrae are filled with fibers the size of glycosaminoglycans (GAGs). Effects of fiber-macromolecule steric and hydrodynamic interactions are included. Focusing on diabetic nephropathy, the physiological and hemodynamic factors employed in the computation are those reported for healthy humans and patients with early-but-overt diabetic nephropathy. The macromolecule concentration is obtained as a finite element solution of the convection-diffusion equation. Computed sieving coefficients averaged along the capillary length agree well with ficoll sieving coefficients from studies in humans for most solute radii. GBM thickening and the loss of the slit diaphragm hardly affect glomerular permselectivity. GAG volume fraction reduction in the endothelial fenestrae, however, significantly increases macromolecule filtration. Increased renal plasma flow rate (RPF), glomerular hypertension, and reduction of lumen osmotic pressure cause a slight sieving coefficient decrease. These effects are amplified by an increased macromolecule size. Our results indicate that glomerular hypertension and the reduction in the oncotic pressure decreases glomerular macromolecule filtration. Reduction of RPF and changes in the glomerular barrier structure associated with DN, however, increase the solute sieving. Damage to GAGs caused by hyperglycemia is likely to be the most prominent factor affecting glomerular size-selectivity.

Deposition of platelet-derived microparticles in podocytes contributes to diabetic nephropathy.

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease in the developed world. Podocyte injury is a critical cellular event involved in the progression of DN. Our previous studies demonstrated that platelet-derived microparticles (PMPs) mediated endothelial injury in diabetic rats. This study aimed to investigate whether PMPs are deposited in podocytes and to assess their potential effects on podocyte injury in DN. The deposition of PMPs in podocytes was assessed by immunofluorescent staining and electron microscopy. The changes in renal pathology and ultra-microstructure were assessed by periodic acid-Schiff staining and electron microscopy, respectively. The expression of inflammatory cytokines and extracellular matrix proteins was measured by immuno-histochemical staining and western blot. PMPs were widely deposited in podocytes of glomeruli in diabetic patients and animal models and closely associated with DN progression. Interestingly, aspirin treatment significantly inhibited the accumulation of PMPs in the glomeruli of diabetic rats, alleviated mesangial matrix expansion and fusion of foot processes, and decreased the protein expression of inflammatory cytokines and extracellular matrix secretion. An in vitro study further confirmed the deposition of PMPs in podocytes. Moreover, PMP stimulation induced the phenotypic transition of podocytes through decreased podocin protein expression and increased protein expression of α-SMA and fibronectin, which was correlated with increased production of inflammatory cytokines. Our findings demonstrated for the first time that the deposition of PMPs in podocytes contributed to the development of DN.

Selective endocytosis controls slit diaphragm maintenance and dynamics in Drosophila nephrocytes.

The kidneys generate about 180 l of primary urine per day by filtration of plasma. An essential part of the filtration barrier is the slit diaphragm, a multiprotein complex containing nephrin as major component. Filter dysfunction typically manifests with proteinuria and mutations in endocytosis regulating genes were discovered as causes of proteinuria. However, it is unclear how endocytosis regulates the slit diaphragm and how the filtration barrier is maintained without either protein leakage or filter clogging. Here, we study nephrin dynamics in podocyte-like nephrocytes of Drosophila and show that selective endocytosis either by dynamin- or flotillin-mediated pathways regulates a stable yet highly dynamic architecture. Short-term manipulation of endocytic functions indicates that dynamin-mediated endocytosis of ectopic nephrin restricts slit diaphragm formation spatially while flotillin-mediated turnover of nephrin within the slit diaphragm is needed to maintain filter permeability by shedding of molecules bound to nephrin in endosomes. Since slit diaphragms cannot be studied in vitro and are poorly accessible in mouse models, this is the first analysis of their dynamics within the slit diaphragm multiprotein complex. Identification of the mechanisms of slit diaphragm maintenance will help to develop novel therapies for proteinuric renal diseases that are frequently limited to symptomatic treatment.

Yishen Huashi Granules Ameliorated the Development of Diabetic Nephropathy by Reducing the Damage of Glomerular Filtration Barrier.

Background: Diabetic nephropathy (DN) is one of the most common complications of diabetes and the primary cause of end-stage renal disease. At present, renin–angiotensin–aldosterone system (RAAS) blockers have been applied as first-class drugs to restrain development of DN; however, its long-term effect is limited. Recent evidence has shown definite effects of Chinese medicine on DN. Yishen Huashi (YSHS) granule is a traditional Chinese Medicine prescription that has been used in the clinic to treat DN, but its mechanism is not understood. Methods: In the present study, both in vitro and in vivo studies were carried out. The DN model was induced by STZ in Wistar rats, and GEnC and HPC cell lines were applied in the in vitro study. Quality of YSHS was evaluated by LC-MS/MS. A metabolomic study of urine was carried out by LC-MS; influence of YSHS on composition of DN was analyzed by network pharmacology. Mechanism of the YSHS on DN was analyzed by Q-PCR, Western Blot, and multi-immunological methods. Results: We found YSHS administration significantly reduced levels of HbA1c and mALB. Histopathological analysis found that YSHS preserved integrity of glomerular filtration barrier by preserving viability of glomerular endothelial cells and podocytes, inhibiting glomerular fibrosis, reducing oxidative stress damage, and enhancing cross-talk among glomerular endothelial cells and podocytes. Network pharmacology, differential metabolite analysis, as well as intracellular pathway experimental study demonstrated that the PI3K/AKT/mTOR signaling pathway played a pivotal role in it. Conclusion: Our present findings supplied new understanding toward the mechanism of YSHS on inhibiting DN.

Essential role of Wtip in mouse development and maintenance of the glomerular filtration barrier.

Wilms' tumor interacting protein (Wtip) has been implicated in cell junction assembly and cell differentiation and interacts with proteins in the podocyte slit diaphragm, where it regulates podocyte phenotype. To define Wtip expression and function in the kidney, we created a Wtip-deleted mouse model using β-galactosidase-neomycin (β-geo) gene trap technology. Wtip gene trap mice were embryonic lethal, suggesting additional developmental roles outside kidney function. Using β-geo heterozygous and normal mice, Wtip expression was identified in the developing kidneys, heart, and eyes. In the kidney, expression was restricted to podocytes, which appeared initially at the capillary loop stage coinciding with terminal podocyte differentiation. Heterozygous mice had an expected lifespan and showed no evidence of proteinuria or glomerular pathology. However, heterozygous mice were more susceptible to glomerular injury than wild-type littermates and developed more significant and prolonged proteinuria in response to lipopolysaccharide or adriamycin. In normal human kidneys, WTIP expression patterns were consistent with observations in mice and were lost in glomeruli concurrent with loss of synaptopodin expression in disease. Mechanistically, we identified the Rho guanine nucleotide exchange factor 12 (ARHGEF12) as a binding partner for WTIP. ARHGEF12 was expressed in human podocytes and formed high-affinity interactions through their LIM- and PDZ-binding domains. Our findings suggest that Wtip is essential for early murine embryonic development and maintaining normal glomerular filtration barrier function, potentially regulating slit diaphragm and foot process function through Rho effector proteins.NEW & NOTEWORTHY This study characterized dynamic expression patterns of Wilms' tumor interacting protein (Wtip) and demonstrates the novel role of Wtip in murine development and maintenance of the glomerular filtration barrier.

Structure of PLA2R reveals presentation of the dominant membranous nephropathy epitope and an immunogenic patch

Membranous nephropathy is an autoimmune kidney disease caused by autoantibodies targeting antigens present on glomerular podocytes, instigating a cascade leading to glomerular injury. The most prevalent circulating autoantibodies in membranous nephropathy are against phospholipase A2 receptor (PLA2R), a cell surface receptor. The dominant epitope in PLA2R is located within the cysteine-rich domain, yet high-resolution structure-based mapping is lacking. In this study, we define the key nonredundant amino acids in the dominant epitope of PLA2R involved in autoantibody binding. We further describe two essential regions within the dominant epitope and spacer requirements for a synthetic peptide of the epitope for drug discovery. In addition, using cryo-electron microscopy, we have determined the high-resolution structure of PLA2R to 3.4 Å resolution, which shows that the dominant epitope and key residues within the cysteine-rich domain are accessible at the cell surface. In addition, the structure of PLA2R not only suggests a different orientation of domains but also implicates a unique immunogenic signature in PLA2R responsible for inducing autoantibody formation and recognition.

MTOR-Dependent Autophagy Regulates Slit Diaphragm Density in Podocyte-like Drosophila Nephrocytes.

Both mTOR signaling and autophagy are important modulators of podocyte homeostasis, regeneration, and aging and have been implicated in glomerular diseases. However, the mechanistic role of these pathways for the glomerular filtration barrier remains poorly understood. We used Drosophila nephrocytes as an established podocyte model and found that inhibition of mTOR signaling resulted in increased spacing between slit diaphragms. Gain-of-function of mTOR signaling did not affect spacing, suggesting that additional cues limit the maximal slit diaphragm density. Interestingly, both activation and inhibition of mTOR signaling led to decreased nephrocyte function, indicating that a fine balance of signaling activity is needed for proper function. Furthermore, mTOR positively controlled cell size, survival, and the extent of the subcortical actin network. We also showed that basal autophagy in nephrocytes is required for survival and limits the expression of the sns (nephrin) but does not directly affect slit diaphragm formation or endocytic activity. However, using a genetic rescue approach, we demonstrated that excessive, mTOR-dependent autophagy is primarily responsible for slit diaphragm misspacing. In conclusion, we established this invertebrate podocyte model for mechanistic studies on the role of mTOR signaling and autophagy, and we discovered a direct mTOR/autophagy-dependent regulation of the slit diaphragm architecture.

The role of dendrin in IgA nephropathy.

Immunoglobulin A nephropathy (IgAN) and its systemic variant IgA vasculitis (IgAV) damage the glomeruli, resulting in proteinuria, hematuria and kidney impairment. Dendrin is a podocyte-specific protein suggested to be involved in the pathogenesis of IgAN. Upon cell injury, dendrin translocates from the slit diaphragm to the nucleus, where it is suggested to induce apoptosis and cytoskeletal changes, resulting in proteinuria and accelerated disease progression in mice. Here we investigated gene and protein expression of dendrin in relation to clinical and histopathological findings to further elucidate its role in IgAN/IgAV. Glomerular gene expression was measured using microarray on 30 IgAN/IgAV patients, 5 patients with membranous nephropathy (MN) and 20 deceased kidney donors. Dendrin was spatially evaluated on kidney tissue sections by immunofluorescence (IF) staining (IgAN patients, n=4; nephrectomized kidneys, n=3) and semi-quantified by immunogold electron microscopy (IgAN/IgAV patients, n=21; MN, n=5; living kidney donors, n=6). Histopathological grading was performed according to the Oxford and Banff classifications. Clinical data were collected at the time of biopsy and follow-up. Dendrin mRNA levels were higher (P=.01) in IgAN patients compared with MN patients and controls and most prominently in patients with preserved kidney function and fewer chronic histopathological changes. Whereas IF staining did not differ between groups, immunoelectron microscopy revealed that a higher relative nuclear dendrin concentration in IgAN patients was associated with a slower annual progression rate and milder histopathological changes. Dendrin messenger RNA levels and relative nuclear protein concentrations are increased and associated with a more benign phenotype and progression in IgAN/IgAV patients.

Urinary Podocyte Excretion Predicts Urinary Protein Selectivity and Renal Prognosis.

Background Urinary podocyte excretion is related to a reduction in glomerular podocyte numbers, glomerulosclerosis, and urinary protein selectivity. To elucidate the role of urinary podocytes in proteinuria and renal prognosis and to identify the factors that cause podocyte detachment, we examined urinary podocytes in 120 renal biopsy patients. Methods Podocytes were identified in urinary sediments stained with fluorescent-labeled anti-podocalyxin antibodies in ten high power fields. The amounts of protein bands, separated by SDS-polyacrylamide gel electrophoresis, were calculated using an image software program and the correlation with urinary podocytes was analyzed. Podocyte surface pores were observed using a low-vacuum scanning electron microscope. The renal prognosis, including induction of hemodialysis or 30% reduction in eGFR, was investigated. Results Urinary podocyte excretion showed a higher positive correlation with albumin excretion compared to IgG, prealbumin, and transferrin. There were no significant correlations between urinary podocyte count and low molecular weight proteins, including β2-microglobulin and α1-microglobulin. The number of podocyte surface pores was positively correlated with proteinuria, suggesting enhanced albumin transcytosis. The hemodynamic pressure on the glomerular capillary wall, including products of pulse pressure and pulse rate (water hammer pressure), was positively correlated with urinary podocyte excretion. Urinary podocyte excretion and Tamm–Horsfall protein (THP) were independent risk factors for renal prognosis but were not related to response to treatment. Conclusion Urinary podocyte excretion was correlated with urinary albumin excretion, indicating specific albumin transport by podocytes. Podocytes were detached from the glomerular capillaries by water hammer pressure and THP was involved in the renal prognosis.

A critical role of the podocyte cytoskeleton in the pathogenesis of glomerular proteinuria and autoimmune podocytopathies.

Selective glomerular filtration relies on the membrane separating the glomerular arterioles from the Bowman space. As a major component of the glomerular filtration barrier, podocytes form foot processes by the actin cytoskeleton, which dynamically adjusts in response to environmental changes to maintain filtration barrier integrity. The slit diaphragms bridge the filtration slits between neighboring foot processes and act as signaling hubs interacting with the actin cytoskeleton. Focal adhesions relay signals to regulate actin dynamics while allowing podocyte adherence to the basement membrane. Mutations in actin regulatory and signaling proteins may disrupt the actin cytoskeleton, resulting in foot process retraction, effacement, and proteinuria. Large-scale gene expression profiling platforms, transgenic animal models, and other in vivo gene delivery methods now enhance our understanding of the interactions among podocyte focal adhesions, slit diaphragms, and actin dynamics. In addition, our team found that at least 66% of idiopathic nephrotic syndrome (INS) children have podocyte autoantibodies, which was defined as a new disease subgroup-, autoimmune podocytopathies. This review outlines the pathophysiological mechanisms of podocyte cytoskeleton protein interactions in proteinuria and glomerular podocytopathy.

Metabolic Syndrome-Related Kidney Injury: A Review and Update.

Metabolic syndrome (MetS) includes visceral obesity, hyperglycemia, dyslipidemia, and hypertension. The prevalence of MetS is 20-25%, which is an important risk factor for chronic kidney disease (CKD). MetS causes effects on renal pathophysiology, including glomerular hyperfiltration, RAAS, microalbuminuria, profibrotic factors and podocyte injury. This review compares several criteria of MetS and analyzes their differences. MetS and the pathogenesis of CKD includes insulin resistance, obesity, dyslipidemia, inflammation, oxidative stress, and endothelial dysfunction. The intervention of MetS-related renal damage is the focus of this article and includes controlling body weight, hypertension, hyperglycemia, and hyperlipidemia, requiring all components to meet the criteria. In addition, interventions such as endoplasmic reticulum stress, oxidative stress, gut microbiota, body metabolism, appetite inhibition, podocyte apoptosis, and mesenchymal stem cells are reviewed.

Nephrin expression in human epidermal keratinocytes and its implication in poor wound closure.

Nephrin is a type-1 transmembrane protein and a component of the slit diaphragm renal-filtration barrier. It has several functions in actin remodeling and cell-cell adhesion. Nephrin is principally located in the kidney glomerulus, but several studies have reported that nephrin is found in the pancreas, brain, and placenta. However, nephrin expression and its role in human skin have not yet been reported. First, using single-cell RNA sequencing, immunohistochemistry, and immuno-electron microscopy, nephrin expression was confirmed in human-skin epidermal keratinocytes. Nephrin expression colocalized with the expression of zonula occludens-1 in keratinocytes and was closely related to keratinocyte cell density, proliferation, and migration. High glucose treatment decreased nephrin expression and compromised keratinocyte cell migration without yes-associated protein nuclear entry. This reduced cell migration under high glucose conditions was improved in nephrin-overexpressing keratinocytes. Nephrin was highly expressed on the margins of re-epithelized epidermis based on in vivo mice and ex vivo human skin wound models. The results demonstrate that nephrin is expressed in human-skin keratinocytes and functions in cell adhesion, proliferation, and migration. In conclusion, this study suggests that nephrin may have a variety of physiological roles in human skin.

Isolated steroid-resistant nephrotic syndrome in a Chinese child carrying a de novo mutation in WT1 gene:a case report and literature review

BackgroundIsolated steroid-resistant nephrotic syndrome (ISRNS) is caused by mutations in the Wilms’ tumor-1 (WT1) gene, which encodes glomerular podocytes and podocyte slit diaphragm.We report a novel 8-year-old female patient with ISRNS carrying a de novo missense mutation in WT1 gene and presenting a new type of pathology, have never been reported.We also systematically review previous reports of ISRNS in Chinese children.Case presentationA 8-year-old Chinese patient who had steroid-resistant nephrotic syndrome,responded poorly to immunosuppressant, and had no extrarenal manifestations. The patient had a female phenotype and karyotype of 46, XX. A new type of renal pathology, proliferative sclerosing glomerulonephritis (PSG),and a de novo missense mutation in WT1 gene, c.748C > T (p.R250W),which have not yet been reported, were identified. She was diagnosed with ISRNS.The patient progressed to end-stage renal disease at the age of 10 years,underwent dialysis and kidney transplant. Renal function and urine protein were normal during 4-year follow-up.ConclusionsWT1 gene testing should be performed to guide treatment for patients with steroid-resistant nephrotic syndrome, especially for isolated cases and female patients.

Nutrient sensing, signaling transduction, and autophagy in podocyte injury: implications for kidney disease.

Podocytes are terminally differentiated epithelial cells of the renal glomerular tuft and these highly specialized cells are essential for the integrity of the slit diaphragm. The biological function of podocytes is primarily based on a complex ramified structure that requires sufficient nutrients and a large supply of energy in support of their unique structure and function in the glomeruli. Of note, the dysregulation of nutrient signaling and energy metabolic pathways in podocytes has been associated with a range of kidney diseases i.e., diabetic nephropathy. Therefore, nutrient-related and energy metabolic signaling pathways are critical to maintaining podocyte homeostasis and the pathogenesis of podocyte injury. Recently, a growing body of evidence has indicated that nutrient starvation induces autophagy, which suggests crosstalk between nutritional signaling with the modulation of autophagy for podocytes to adapt to nutrient deprivation. In this review, the current knowledge and advancement in the understanding of nutrient sensing, signaling, and autophagy in the podocyte biology, injury, and pathogenesis of kidney diseases is summarized. Based on the existing findings, the implications and perspective to target these signaling pathways and autophagy in podocytes during the development of novel preventive and therapeutic strategies in patients with podocyte injury-associated kidney diseases are discussed.

Suppressing the activity of CXCR4 down-regulates the expression of renal fibrosis related genes in primary glomerular cells.

BackgroundC-X-C chemokine receptor type 4 (CXCR4) has a certain effect on renal fibrosis, and there are few specific studies in cells. We want to investigate the impact of suppressing CXCR4 activity on the expression of renal fibrosis-related genes in primary glomerular endothelial cells, mesangial cells, and podocytes.MethodsImmunofluorescence assays were used to determine the purity of isolated glomerular endothelial cells, mesangial cells, and podocytes. CXCR4 knockdown cell lines were established by transfecting the short hairpin (sh)RNA against CXCR4. T140 and AMD3100 were used to inhibit the activity of CXCR4. LY294002 was used to inhibit the activity of phosphoinositide 3-kinase (PI3K). The mRNA expression of CXCR4 was determined by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). The protein expression of CXCR4, collagen IV, matrix metallopeptidase (MMP)-9, PI3K, Rac1, and vascular cell adhesion protein 1 (VCAM-1) was evaluated by Western blot analysis.ResultsHigh purity was observed on isolated primary glomerular endothelial cells and podocytes. However, the purity of isolated mesangial cells was relatively low. The mRNA expression of CXCR4 was significantly suppressed by the transfection of shRNA. Compared to control cells, the expression of CXCR4, collagen IV, MMP-9, PI3K, Rac1, and VCAM-1 were dramatically downregulated in cell lines transfected with shRNA against CXCR4. Furthermore, cell lines treated with T140, AMD3100, or LY294002 also showed downregulated expression of these proteins compared to untreated cells. No significant differences were observed in the protein expression of these proteins between control cells and cells transfected with the shRNA negative control (NC).ConclusionsSuppressing the activity of CXCR4 downregulated the expression of renal fibrosis-related genes in primary glomerular cells, even under a non-inflammatory state.

Clinical Significance of Glomerular Autophagy in Evaluation of Diabetic Kidney Disease Progression.

BackgroundDiabetic kidney disease (DKD) is closely associated with the death or survival of resident kidney cells.AimThe purpose of this study was to determine the changes in renal cell survival and death in DKD and their diagnostic values in DKD progression.Materials and MethodsThis study analyzed a dataset of renal tissues from DKD patients to identify changes in genes associated with renal cell death and survival. Our findings were subsequently validated in human kidney tissues. Differential indicators of DKD patients’ clinicopathological data screened by stepwise regression and glomerular P62 protein expression were included in binary logistic regression analysis to assess the impact of these parameters on DKD progression. A receiver operating characteristic (ROC) curve analysis was employed to evaluate the diagnostic value of P62 protein in DKD progression.ResultsBioinformatics analysis results revealed that glomerular autophagy in DKD was more significantly altered, which was consistent with the semi-quantitative results of P62 in glomeruli. Further studies established that P62 expression was mainly increased in podocytes. Stepwise regression analysis indicated that changes in the expressions of glomerular P62 and apolipoprotein A1 (ApoA1) might be involved in the progression of DKD. However, binary logistic regression analysis results suggested that only P62 was significantly associated with DKD development. ROC curve analysis showed that the area under the curve (AUC) of P62 for the detection of DKD was 0.905.ConclusionAutophagy inhibition occurred in both glomeruli and tubules, and was most pronounced in glomerular podocytes. The levels of P62 protein in glomeruli, as an autophagy activity indicator, was one of the predictors of entering the stage of macroalbuminuria in DKD.

Creating bioinformatics matrix of molecular markers to predict risk-associated health disorders

Long-term or permanent chemical ambient air pollution in residential areas is among priority factors that cause medical and demographic losses. It is necessary to achieve greater precision when assessing risks of changes in homeostasis at their early reversible stage (molecular level). These changes are highly likely to transform into pathological processes at an older age in case the exposure persists. Our research goal was to create a bioinformatics matrix of molecular markers to predict risk-associated health disorders (exemplified by a marker of exposure). We introduced a stepwise research algorithm that involved using the proteome technology to identify expressed proteins and cause-effect relations between them and influencing factors; revealing molecular-cellular and functional relationships within the “exposure factor – gene – protein – negative outcome” system to predict risk-associated health disorders. The algorithm was implemented to examine the proteomic blood plasma profile of children aged 3–6 years living under long-term aerogenic exposure to fluoride-containing compounds. We established certain changes in the proteomic profiles of the exposed children in comparison with non-exposed ones as per 27 identified proteins. A bioinformatics matrix was created on the example of cathepsin L1; we established that changes in the level of this protein had a cause-effect relationship with fluoride ion concentrations in urine. Qualitative synthesis of molecular-cellular localization, functional and tissue belonging showed that cathepsin L1 expression caused by elevated fluoride ion levels in urine could affect extracellular matrix remodeling, degradation and post-translation modification of proteins in cells of the lungs, large intestine, and pancreas, in cardiomyocytes and in glomerular podocytes. It also mediated proteolysis of the subunits of the SARS-CoV-2 S1 protein necessary for the virus penetration into a cell and its replication. This created bioinformatics matrix exemplified by cathepsin L1 made it possible to predict risk-associated negative outcomes in exposed people including cardiomyopathy, colitis, glomerulonephritis, diabetes mellitus, atherosclerosis, and coronavirus infection. These predictive estimates raise effectiveness of early detection and development of preventive measures aimed at minimizing possible negative outcomes.

Создание биоинформационной матрицы молекулярных маркеров для прогнозирования риск-ассоциированных нарушений здоровья

Long-term or permanent chemical ambient air pollution in residential areas is among priority factors that cause medical and demographic losses. It is necessary to achieve greater precision when assessing risks of changes in homeostasis at their early reversible stage (molecular level). These changes are highly likely to transform into pathological processes at an older age in case the exposure persists. Our research goal was to create a bioinformatics matrix of molecular markers to predict risk-associated health disorders (exemplified by a marker of exposure). We introduced a stepwise research algorithm that involved using the proteome technology to identify expressed proteins and cause-effect relations between them and influencing factors; revealing molecular-cellular and functional relationships within the “exposure factor – gene – protein – negative outcome” system to predict risk-associated health disorders. The algorithm was implemented to examine the proteomic blood plasma profile of children aged 3–6 years living under long-term aerogenic exposure to fluoride-containing compounds. We established certain changes in the proteomic profiles of the exposed children in comparison with non-exposed ones as per 27 identified proteins. A bioinformatics matrix was created on the example of cathepsin L1; we established that changes in the level of this protein had a cause-effect relationship with fluoride ion concentrations in urine. Qualitative synthesis of molecular-cellular localization, functional and tissue belonging showed that cathepsin L1 expression caused by elevated fluoride ion levels in urine could affect extracellular matrix remodeling, degradation and post-translation modification of proteins in cells of the lungs, large intestine, and pancreas, in cardiomyocytes and in glomerular podocytes. It also mediated proteolysis of the subunits of the SARS-CoV-2 S1 protein necessary for the virus penetration into a cell and its replication. This created bioinformatics matrix exemplified by cathepsin L1 made it possible to predict risk-associated negative outcomes in exposed people including cardiomyopathy, colitis, glomerulonephritis, diabetes mellitus, atherosclerosis, and coronavirus infection. These predictive estimates raise effectiveness of early detection and development of preventive measures aimed at minimizing possible negative outcomes.