bluuebunny/crossref_metadata_2025_split huggingface dataset:
#1521 EZH2 promotes cyst growth in autosomal dominant polycystic kidney disease
Authors: Mao Zhiguo , Xue Cheng 
Published: May 2024

Abstract

Background and Aims
Autosomal dominant polycystic kidney disease (ADPKD) is the leading hereditary kidney disease worldwide. Epigenetic modulations of genes and proteins play important roles in ADPKD pathogenesis. In this study, the role of enhancer of zeste homolog 2 (EZH2), a histone lysine methyltransferase, was investigated in ADPKD.

Method
To elucidate the role of EZH2 in ADPKD pathogenesis, we employed inducible knockout models, specifically targeting Pkd1 alone (Pkd1fl/fl) or both Pkd1 and EZH2 (Pkd1fl/fl: Ezh2fl/fl) in mouse models. Molecular analyses included assessing EZH2 expression levels and H3K27 trimethylation in Pkd1 knockout cells, kidney tissues from Pkd1 knockout mice, and samples from ADPKD patients. Functional investigations involved the use of EZH2-specific inhibitors, GSK126 and EPZ-6438, to inhibit EZH2 activity. Additionally, Ezh2 knockdown was employed to assess its impact on cystogenesis in MDCK cells. The embryonic kidney cyst model was utilized to evaluate the effects of GSK126 and EPZ-6438 on cyst growth.

Results
We found that EZH2 expression and the trimethylation of lysine 27 on histone H3 (H3K27) were upregulated in Pkd1 knockout cells and kidney tissues of Pkd1 knockout mice and ADPKD patients. Using EZH2-specific inhibitors GSK126/EPZ-6438 and knockdown of Ezh2 both suppressed cystogenesis in MDCK cells. GSK126 and EPZ-6438 delayed cyst growth in the embryonic kidney cyst model. Double knockout of Pkd1 and Ezh2 significantly decreased the kidney volume, cyst indexes, H3K27 methylation level, and the proliferation of renal cystic epithelial cells compared with Pkd1 knockout mice. Moreover, GSK126 delayed cyst growth and protected renal function in both early- and late-onset Pkd1 conditional knockout mice. EZH2 promoted the proliferation of renal cystic epithelial cells by activating STAT3 through H3K27 methylation.

Conclusion
Inhibiting EZH2 emerged as a promising strategy to impede cyst growth and attenuate disease progression across various PKD models. These findings establish a molecular foundation for the potential use of EZH2-specific inhibitors in delaying ADPKD cyst growth in the future.
#1558 Mutational spectrum of X-linked hypophosphatemia (XLH) in Hungarian patients
Authors: Balogh Istvan , Szabo Tamas , Reusz Gyorgy , Mikes Balint , Koczok Katalin , Madar Laszlo , Nagy Orsolya , Till Agnes , Meichelbeck Krisztina , Pfliegler Gyorgy , Szabo Andras , Lengyel Anna 
Published: May 2024

Abstract

Background and Aims
X-linked hypophosphatemia (XLH), the most common form of hypophosphatemic rickets, is caused by genetic alterations in the PHEX gene. Prevalence of the X-linked disease is ∼1/20,000. The PHEX gene has 22 exons and encodes a 749 amino acid protein with homology to zinc metallopeptidases. The physiological protein target for PHEX cleavage is unknown. PHEX promotes mineralization by regulating the expression of FGF23. To date, more than 800 disease-causing variants in the PHEX gene have been described in XLH patients. These variants might occur across the entire gene and include missense, nonsense, frameshift, splice site, copy-number variants with a consequence of loss of PHEX protein function. Genetic confirmation of XLH has significant clinical importance from risk prediction to modern treatment options. Here we describe the genetic results of 20 mutation-positive patients from 18 unrelated families, the first such report from Hungary.

Method
The cohort consisted of 8 male and 12 female patients (mean age at genetic diagnosis (range): 8.25 years (3-17 years) and 12 years (2-32 years)). Genomic DNA was isolated from peripheral blood leukocytes and in the mosaic case also from mouthwash sample. PHEX sequencing was performed using next generation sequencing with a custom designed library preparation kit (Twist Biosciences) on an Illumina MiSeq instrument. For the bioinformatic analysis, NextGene software was used. All small-scale mutations were confirmed by Sanger sequencing. For copy number variation (CNV) analysis, a coverage-based pipeline was used. Detected CNVs were confirmed using multiplex ligation-dependent probe amplification (MLPA). Mutation classification was performed according to the ACMG guidelines.

Results
All female patients were heterozygous, while all but one male patients were hemizygous. In case of one male patient, a mosaic deletion of exon 10 was observed. Most common mutation type was nonsense (n = 7) followed by small deletions/insertions (n = 6) and splicing alterations (n = 3). One missense mutation was detected. CNVs were responsible in three cases (two large deletions and one large duplication). From the 11 most common PHEX alleles known from the literature (Hum Mutat 2022;43:143-57), three (c.2104C &gt; T, c.2239C &gt; T, c.871C &gt; T) were detected in our cohort. Nine novel, previously undescribed alterations were found: c.264G &gt; A, c.1073_1074delGA, c.1148dupA, c.1645+1G &gt; C, c.1682G &gt; A, c.1701-1G &gt; C, c.2150T &gt; G, c.2172delT, e6-15dup.

Conclusion
Our data shed more light on the distribution of the PHEX causative variations in the Hungarian XLH patients and opens the possibility of the state-of-the-art treatment in many of them.
#3124 How well do risk assessment guidelines perform for ADPKD?
Authors: Cam Mauricio Alejandro Miranda 
Published: May 2024

Abstract

Background and Aims
The approval of Tolvaptan for treatment of ADPKD heralds a new era when mechanism-based therapy is now possible. However, Tolvaptan is an expensive drug associated with potentially serious side effects and is currently reserved for patients at high-risk for progression to ESKD. Two sets of risk assessment guidelines for ADPKD are now available based on the consensus of two panels of nephrologists from Canada and Europe. However, how well do these guidelines perform in risk assessment has not been formally assessed.

Method
We conducted a prospective study in 474 patients with typical imaging pattern of ADPKD by MRI who also had detailed clinical and laboratory data. We used age- and height-adjusted total kidney volume to derive the Mayo Clinic Imaging Class as a “gold-standard” for risk assessment (i.e. low-risk: 1A-1B; high-risk: 1C-1E). We then applied the revised Canadian guidelines (Can J Kidney Health Dis. 2018) and the updated European guidelines (NDT 2022) to our patient cohort to assess their performance.

Results
The study cohort consisted of 286/474 (60%) high-risk patients with MCIC 1C-1E. Applying the updated Canadian risk assessment algorithm resulted in exclusion of 245/474 (52%) patients including 86/286 (30%) of the high-risk patients. The resultant cohort (229/474) was enriched with 88% high-risk patients but also included 12% of low-risk patients. The updated European guidelines provide a 3-step hierarchal algorithm, when applied resulted in exclusion of 55% (157/286) of high-risk patients. During the last step, 122 patients could not be classified due to a lack of eGFR slope information. The resultant cohort (180/474) was enriched with 72% high-risk patients but also included 28%(51/180) of low-risk patients.

Conclusion
Risk assessment in ADPKD is an evolving process that needs to be redefined by new clinical data and test technologies. Clinical guidelines should be evaluated using real-life data and those that enrich high-risk patients while minimizing low-risk patients have the most clinical utility
#844 Renal manifestations of immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome: an updated systematic review
Authors: Lee Keum Hwa , Hwang Eun Jae , Shin Jae Il , Park Se Jin 
Published: May 2024

Abstract

Background and Aims
Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is a systemic autoimmune genetic disorder caused by mutation of the forkhead box protein 3 (FOXP3) gene. We performed this study to analyze the clinical and demographic characteristics of renal involvement in IPEX patients, genotype-phenotype correlations and the effect of renal involvement on patient outcome.

Method
We performed a literature search (PubMed and EMBASE) to systematically investigate the case reports of IPEX with renal involvement which were published before Dec 21st, 2023.

Results
A total of 37 patients were identified. All IPEX patients included had FOXP3 mutations which were most frequently located in the forkhead domain. Among 25 patients in whom detailed information is available, 22 showed single presentation (6 proteinuria, 8 nephrotic syndrome (nephrotic range proteinuria), 3 acute glomerulonephritis, 5 renal insufficiency), 2 showed multiple presentations (1 nephrotic range proteinuria, microscopic hematuria and 1 nephrotic range proteinuria, microscopic hematuria, renal insufficiency). Renal biopsy was documented in 19 patients. Membranous nephropathy (n = 9) was most common, followed by Interstitial nephritis (n = 3), membranoproliferative nephropathy (n = 2), tubulopathy (n = 2), mesangial proliferative glomerulonephritis (n = 2), autoimmune nephritis (n = 1). Nephrotic syndrome was more frequent in patients with intron 6 mutation (p &lt; 0.05). However, renal presentation of IPEX syndrome was not related to patient outcome (death).

Conclusion
We found renal involvement is one of the important manifestations of IPEX syndrome and membranous nephropathy was most common. Close renal monitoring is necessary to detect renal involvement of IPEX syndrome. Further studies are necessary to compare the course of glomerulonephritis between IPEX-related and IPEX-unrelated one. Response to treatment should also be elucidated in patients with IPEX in the future.
#1040 Correlation of genotype to disease onset age and hypertension diagnosis in autosomal dominant polycystic kidney disease
Authors: Evangelou Eirini , Konsta Maria , Gkalitsiou Dimitra , Vasileiou Kyriaki , Poula Angeliki , Markou Niki , Poulli Tsielestina , Palaiologou Danai , Kanellopoulou Konstantina , Tsirpanlis George 
Published: May 2024

Abstract

Background and Aims
Autosomal Dominant Polycystic Kidney Disease (ADPKD) is the predominant genetic disease leading to End Stage Kidney Disease (ESKD). Genetic identity could correlate to the disease profile. Correlations between genetic and phenotype characteristics in a cohort of ADPKD patients are investigated.

Method
Genetic analysis was conducted in 85 patients with an ADPKD phenotype, employing targeted Next Generation (tNGS) or Sanger Sequencing and Multiplex ligation-dependent probe amplification (MLPA). Medical history, clinical and laboratory data, including Renal Magnetic Resonance Imaging (MRI) for Total Kidney Volume (TKV) measurement (in 66 patients), were recorded and subsequently correlated to the respective genotypes.

Results
Eighty-five patients (43 females, 42 males, 33 ± 16 years old) were included in the study. The mean age at diagnosis of the disease was at 21.5 ± 13 (0.6-69) years. Fifty-eight out of 85 patients (68%) had a familial history of ADPKD. The mean age at which the affected parent reached ESKD was 53.0 ± 9 years. Hypertension was diagnosed in 60 individuals (71%) within the study cohort. The mean age at hypertension diagnosis was 31 ± 11 years. In the assessment based on height-adjusted TKV and age, the Mayo Clinic Imaging Categories revealed that 9% of patients were classified as 1A, 20% as 1B, 29% as 1C, 29% as 1D, and 13% as 1E. Mutations in PKD1 gene were detected in 70 patients (82%), with 61% exhibiting truncating mutations and 39% non-truncating mutations, while PKD2 mutations were identified in 15 patients (18%). The average age of ADPKD diagnosis differed among genetic subgroups. Patients carrying PKD1-truncating mutations were diagnosed at 17.6 ± 11 years, those with PKD1-non-truncating mutations at 24.5 ± 12 years, and those with PKD2 mutations at 27.3 ± 16 years (p = 0.01). Moreover, the mean age at which the affected parent reached ESKD was 50 ± 8 years, 55 ± 10 and 60 ± 7 years in PKD1-truncating, PKD1-non-truncating and PKD2 patients respectively (p = 0.04). Additionally, the mean age of hypertension diagnosis was 29 ± 12 years in PKD1-truncating, 30 ± 10 years in PKD1-non-truncating and 40 ± 7 years in PKD2 patients (p = 0.05).

Conclusion
Mutation type correlates with the age of ADPKD diagnosis, the renal survival within families and the hypertension onset. Patients with PKD1-truncating mutations manifest an earlier onset of both the disease and hypertension compared to those with PKD2 gene mutations.
#2372 Investigating the effects of low-level and transient DNA damage on kidney health in a novel mouse model of aging
Authors: Takasu Masanobu , Kishi Seiji , Kirita Yuhei , Nagasu Hajime , Kidokoro Kengo , Sasaki Tamaki , Hayano Motoshi , Kashihara Naoki 
Published: May 2024

Abstract

Background and Aims
Increasing life expectancy worldwide underscores the importance of addressing the effects of aging on organ and cell function. Aging is characterized by a gradual decline in organ function that varies among individuals and is influenced by lifestyle choices and various external factors that induce DNA stress. This mismatch between kidney aging and an individual's lifespan contributes to the increase in end-stage renal disease. Among the kidney's constituent cells, the proximal tubules are frequently damaged by external factors such as ischemia and drugs. Our research has focused on DNA damage and its repair mechanisms (DDR) caused by these injuries, and we have previously shown that extensive DNA damage beyond the capacity of DDR or abnormalities in DDR cause cellular senescence in proximal tubules, resulting in incomplete renal repair after injury (Kishi et al. Sci Transl Med 2019, J Clin Invest 2019). In this study, we extend these studies and test whether acquired and mild DNA stress induces renal senescence using a novel mouse model of aging, the Inducible Changes to the Epigenome (ICE) mouse (Hayano et al. Cell. 2023).

Method
ICE mice were generated by mating I-PpoI STOP/+ mice with CreERT2/+ mice. I-PpoI, an endonuclease, cleaves DNA only upon administration of tamoxifen and the resulting DNA damage is subsequently repaired by the DDR. To induce transient DNA damage, 4- to 6-month-old mice were fed a tamoxifen-containing diet for 3 weeks and then housed until they reached 14 months of age. A comprehensive renal analysis was then performed, which included renal tissue evaluation, single-nucleus RNA sequencing, q-PCR, and Western blot analysis for phenotypic analysis of mouse kidneys.

Results
No significant histological changes were observed in the kidney tissues between the ICE mice and the control group, and the levels of interstitial fibrosis were comparable. To ensure unbiased evaluation, we performed single-nucleus RNA-seq. In ICE mice, there was an increased presence of proximal tubules with incomplete repair expressing KIM-1 and VCAM-1. In addition, ICE mice showed increased gene expression of DNA repair-related enzymes (Mgmt) in proximal tubules and evidence of cellular senescence. No differences in mitochondrial number or biosynthetic capacity were observed.

Conclusion
The consequences of short-term and transient DNA damage were found to have lasting effects on the kidney. In particular, significant changes were observed in the proximal tubules, where DNA instability and accelerated cellular senescence were evident, suggesting an impaired repair phenotype within the proximal tubules. This may be related to increased susceptibility to various external stimuli. For further detailed analysis, studies using proximal tubule-specific ICE mice are currently performed.
#1144 Role of PPAR-alpha in folic acid-induced tubulointerstitial fibrosis
Authors: Estrela Gabriel , Arruda Adriano , Barrera-Chimal Jonatan , Araujo Ronaldo 
Published: May 2024

Abstract

Background and Aims
PPAR-alpha is a nuclear receptor that plays a major role in the regulation of lipid metabolism. Activation of PPAR-alpha has been shown to have beneficial effects in renal diseases. Acute kidney injury (AKI), even if followed by renal recovery, is a risk factor for the future development of chronic kidney disease (CKD) and end-stage renal disease (ESRD). Progressive tubulointerstitial fibrosis is the final common pathway for all kidney diseases leading to chronic renal failure. Our main objective was to determine the importance of PPAR-alpha in tubulointerstitial fibrosis in folic acid induced nephropathy.

Method
Male C57/Bl6 and PPARKO (C57Bl6 background) mice were divided into 4 groups, Control, Folic Acid, Gemfibrozil + Folic Acid and PPARKO + Folic Acid. Animals have been treated with a single dose of Folic Acid (250 mg/kg i.p) and Gemfibrozil (150 mg/kg gavage) euthanized after 28 days for. Renal parameters, histology, real time PCR were performed to investigate renal injury, inflammation, and fibrosis.

Results
After 28 days of folic acid inducing CKD. PPARKO showed the same levels of injury as folic acid alone treated mice, however PPAR-alpha activation with gemfibrozil decreased urinary volume (Folic Acid: 3.870 ± 0.679 Gemfibrozil: 1,242 ± 0,223), creatinine (Folic Acid: 0,7940 ± 0,0357 Gemfibrozil: 0,5820 ± 0,0288), urea levels (Folic Acid: 79,23 ± 3,20 Gemfibrozil: 46,11 ± 3,874), showed less tubulointerstitial fibrosis (Folic Acid: 0,5837 ± 0,0426), Gemfibrozil: 0,2423 ± 0,0293) and lower urine protein/creatinine ratio (Folic Acid: 5,486 ± 0,588 Gemfibrozil: 2,536 ± 0,127).

Conclusion
PPAR-alpha deletion did not show protection in chronic phase, in the other hand PPAR-alpha activation with gemfibrozil showed to be effective against tubulointerstitial fibrosis.
#2983 Correlation of microRNA expression with IgA nephropathy progression: preliminary results
Authors: Konieczniak Karolina , Jesiotr Marzenna , Rymarz Aleksandra , Niemczyk Stanisław 
Published: May 2024

Abstract

Background and Aims
IgA nephropathy (IgAN) is the most common cause of glomerulonephritis worldwide. IgAN is diagnosed based on the result of histopathological examination. The risk factors for disease progression primarily include the level of impairment of renal function at the time of diagnosis (GFR &lt; 60 ml/min/1.73 m2), the presence of hypertension, daily administration of more than 1.0 g, and the occurrence of hematuria. MicroRNAs (miRNAs) are important regulators of gene expression. Their role has a significant impact on the proper functioning of the body, and disorders related to their expression can lead to the development of many pathological processes in the body. The study aimed to assess the dependence of microRNA expression on the stage of the disease in patients with IgA nephropathy.

Method
A study was conducted involving patients newly diagnosed with IgA nephropathy based on histopathological examination results. The expression of microRNA molecules (miR-146a, miR-155, miR-200b, miR-429) was determined in urine sediment and blood. The analysis focused on examining the relationship between microRNA expression and the stage of disease progression (proteinuria, renal parameters). Blood and urine tests were performed before the start of immunosuppressive treatment with glucocorticosteroids according to the Pozzi regimen.

Results
Twenty-seven patients were included in the study group- 14 women (51.9%) and 13 men (48.1%). Nephrotic-range proteinuria (&gt;3000 mg/24 h) was observed in 5 patients (18.5%), while subnephrotic proteinuria was present in 22 patients (77.8%). Reserved kidney function (eGFR &gt; 90) was found in 17 patients (63%). The exact distribution of results according to the stage of renal failure is given in the Table 1.
Statistically significant positive correlation was found between serum creatinine concentration and miR-200b expression in urine (R = 0,398, p = 0,049). Initially, no statistically significant correlation was found between the expression of selected miRNA molecules and the degree of 24-hour proteinuria.

Conclusion
MiRNA molecules may be promising, non-invasive biomarkers widely used in clinical practice. Determining the viability of clinical use of microRNA molecules will require a panel of miRNAs or miRNAs used in combination with other biomarkers and clinical outcomes to improve diagnostic utility.
#2074 Aberrant m6A modification pattern and m6A-related proteins expression in SLE
Authors: Tang Chun , Liu Yu , Wang Xiaohua , Huang Mingcheng , Luo Ailing , Liu Shanshan , Cai Mansi , Li Weinian , Yuan Shiwen , Zheng Zhihua , Liu Xiaoping 
Published: May 2024

Abstract

Background and Aims
Systemic lupus erythematosus (SLE) is an autoimmune disease of unknown cause. N6-methyladenosine (m6A) is the most common mRNA modification and is involved in various immune processes leading to immune homeostasis disorders. However, the role of m6A in dysregulated immune response of SLE remains unknown. Here, we aim to explore the m6A pattern and expression of m6A-related proteins in the SLE.

Method
Peripheral blood mononuclear cells (PBMCs) from healthy controls and SLE patients were collected to compare the m6A modification profile by methylated RNA immunoprecipitation sequencing (MeRIP-seq). Expression of 3 m6A-related proteins, including methyltransferase 3 (METTL3), Alkb homologue 5 (ALKBH5), and Fat mass and obesity-associated protein (FTO) and in PBMCs of SLE patients were detected using western blotting (WB). Renal METTL3 expression was further examined in MRL/lpr mice using WB and immunofluorescence.

Results
SLE patients contained only 28.74% of the same m6A peaks as healthy controls, and 7.881% of the peaks were specific in SLE group (Fig. 1A). The m6A differential peaks were enriched in exon, intron and near 3’ UTR region (Fig. 1B). In addition, compared with healthy controls, m6A modified motifs were obviously aberrant in SLE patients (Fig. 1C). GO and KEGG enrichment analysis showed that some of the m6A peak differential genes were associated with regulation of cellular process, and cytokine-cytokine receptor interaction signaling pathway (Fig. 1D and 1E). Expression of METTL3 and ALKBH5 in SLE patients were significantly increased (METTL3, SLE-AP vs HC, p &lt; 0.001; SLE-SP vs HC, p = 0.0042; ALKBH5, SLE-AP vs HC, p &lt; 0.001; SLE-SP vs HC, p &lt; 0.001; Fig. 1F). There were no significant differences in FTO expressions between the two groups (SLE-AP vs HC, p = 0.167; SLE-SP vs HC, p = 0.477; Fig. 1F). Compared with C57BL/6 mice, renal METTL3 in the MRL/lpr mice was distinctly elevated (p &lt; 0.001; Fig. 1G), which co-localized with CD138 + plasma cells (Fig. 1H).

Conclusion
These results suggested a distinctly abnormal m6A modification features and m6A-related proteins in SLE patients, indicating the potential significant role of m6A in the pathogenesis of SLE.