bluuebunny/crossref_metadata_2025_split huggingface dataset:
#1431 Risk factors of adverse cardiovascular events in the early postoperative period in kidney transplant recipients
Authors: Smaliakova Maria , Kalachyk Aleh 
Published: May 2024

Abstract

Background and Aims
Kidney transplantation improves quality of life and increases life expectancy in patients with Stage 5 Chronic Kidney Disease. However, the frequency of adverse cardiovascular events in the postoperative period remains high and reduces the effectiveness of transplantation.
The aim was to study the incidence of cardiovascular risk factors in the preoperative period in kidney transplant recipients with adverse cardiovascular events in the early postoperative period.

Method
The study included 51 kidney transplant recipients whose age was 46.1 ± 4.6 years. 12 (23.5%) recipients had adverse cardiovascular events (acute myocardial infarction, unstable angina, rhythm disturbance, complicated hypertensive crisis) in the early postoperative period. 39 (76.5%) recipients with uncomplicated postoperative period formed the comparison group. The study groups were comparable by gender and age.

Results
Traditional cardiovascular risk factors were assessed. The study groups had comparable rates of arterial hypertension, obesity, hyperglycemia, dyslipidemia and smoking in the preoperative period and graft function in the postoperative period.
The study groups didn't have significant differences in the incidence of anemia and hemoglobin blood concentration. But the erythropoietin blood level in the preoperative period in recipients with adverse cardiovascular events was higher—38.5 (23.5-155.0) mU/mL versus 16.0 (10.0-32.0) mU/mL, p &lt; 0.01, and hypererythropoietinemia was diagnosed more often—58.3% (n = 7) versus 25.6% (n = 10), p &lt; 0.05, than in patients without cardiovascular events.
The incidence of elevated interleukin-6 blood level in the preoperative period was higher in recipients with adverse cardiovascular events—25.0% (n = 3) versus 5.1% (n = 2), p &lt; 0.05. At the same time C-reactive protein levels and white blood cell counts were not significantly different.
Recipients with adverse cardiovascular events had a lower left ventricular ejection fraction—59.5 ± 10.6% versus 65.6 ± 7.1%, p &lt; 0.05, and a higher incidence of left ventricular diastolic dysfunction in the preoperative period—75.0% (n = 9) versus 35.9% (n = 14), p &lt; 0.05, than in recipients without cardiovascular complications.

Conclusion
Kidney transplant recipients with adverse cardiovascular events in the early postoperative period had a higher incidence of left ventricular diastolic dysfunction, increased blood levels of erythropoietin and interleukin-6 and a lower left ventricular ejection fraction before transplantation than recipients with an uncomplicated postoperative period.
#1315 Management and long-term outcome of recurrent idiopathic FSGS in pediatric renal transplant recipients
Authors: Toder Moran Plonsky , Magen Daniella , Pollack Shirley , Eisenstein Israel , Tibi Rami , Yakubov Renata , Zebegret Irina Libinson 
Published: May 2024

Abstract

Background and Aims
Focal segmental glomerulosclerosis (FSGS) is a leading cause of pediatric end-stage renal disease (ESRD). While approximately 30% of pediatric FSGS is attributed to monogenic disorders, most cases are idiopathic, carrying a high risk of post-transplantation recurrence and graft loss. Commonly used protocols for recurrent FSGS (rFSGS) include plasmapheresis or immunoadsorption, and/or immunomodulatory therapy. We retrospectively evaluated the efficacy and safety of early plasmapheresis followed by rituximab therapy for induction of remission in rFSGS.

Method
Between 2014-2023, 8/65 pediatric renal transplant recipients at our center were diagnosed with idiopathic FSGS. Five patients underwent preventive plasmapheresis initiated between day 7 pre-transplantation to day 1 post-transplantation, depending on donor source (living/deceased). rFSGS, was diagnosed based on nephrotic range proteinuria of no other cause, and managed with daily plasmapheresis, followed by frequency tapering. Failure to achieve complete remission while on prolonged plasmapheresis was managed with Rituximab therapy.

Results
6/8 patients (75%) experienced rFSGS. All achieved partial or complete remission with plasmapheresis therapy. Nevertheless, 5/6 patients exhibited plasmapheresis-dependence, thereby necessitating rituximab therapy. Of these, 3/5 patients achieved sustained remission enabling plasmapheresis cessation, while in 2/5 showed markedly improved proteinuria, enabling reduction of plasmapheresis frequency to once weekly. Adverse effects included rituximab-induced serum sickness in one patient, requiring therapy discontinuation. While one patient suffered from graft loss due to humoral rejection, no graft was lost to rFSGS, and all other grafts remained functional over an average follow-up period of 50 months.

Conclusion
We suggest that early introduction of plasmapheresis and rituximab therapy effectively induces remission in most post-transplantation rFSGS, is well tolerated, and prevents graft loss. Additional, large scale studies are needed to establish our observation.
#1076 DNA hypomethylation of Syk induces oxidative stress and apoptosis via the PKCβ/ P66shc signaling pathway in diabetic kidney disease
Authors: Liu Fang , Qin Chunmei 
Published: May 2024

Abstract

Background and Aims
Epigenetic alterations, especially DNA methylation, have been shown to play a role in the pathogenesis of diabetes mellitus (DM) and its complications, including diabetic kidney disease (DKD). Spleen tyrosine kinase (Syk) is known to be involved in immune and inflammatory disorders. We, therefore, investigated the possible involvement of Syk promoter methylation in DKD, and the mechanisms underlying this process.

Method
Kidney tissues were obtained from renal biopsies of patients with early and advanced DKD. A diabetic mouse model (ApoE−/−DM) was generated from ApoE knockout (ApoE−/−) mice using a high fat and high glucose diet combined with low-dose streptozocin (STZ) intraperitoneal injection. We also established an in vitro model using HK2 cells.

Results
A marked elevation in the expression levels of Syk, PKCβ, and P66shc in renal tubules was observed in patients with DKD. In ApoE−/− DM mice, Syk expression and the binding of Sp1 to the Syk gene promoter were both increased in the kidney. In addition, the promoter region of the Syk gene exhibited hypomethylation. Syk inhibitor (R788) intervention improved renal function and alleviated pathologic changes in ApoE−/− DM mice. Moreover, R788 intervention alleviated oxidative stress and apoptosis and down-regulated the expression of PKCβ/ P66shc signaling pathway proteins. In HK2 cells, oxLDL combined with high glucose stimulation upregulated Sp1 expression in the nucleus (compared with control and oxLDL groups), and this was accompanied by an increase in the binding of Sp1 to the Syk gene promoter. SP1 silencing down-regulated the expression of Syk and inhibited the production of reactive oxygen species and cell apoptosis. Finally, PKC agonist intervention reversed the oxidative stress and apoptosis induced by Syk inhibitor (R406).

Conclusion
In DKD, hypomethylation at the Syk gene promoter was accompanied by an increase in Sp1 binding at the promoter. As a consequence of this enhanced Sp1 binding, Syk gene expression was upregulated. Syk inhibitors could attenuate DKD-associated oxidative stress and apoptosis via down-regulation of PKCβ/ P66shc signaling pathway proteins. Together, our results identify Syk as a promising target for intervention in DKD.
#2683 Targeted antibiotic modulation of the gut microbiome ameliorates hypertensive kidney damage
Authors: Bartolomaeus Hendrik , Wimmer Moritz , Anandakumar Harithaa , Vecera Valentin , Löber Ulrike , Forslund Sofia K , Müller Dominik N , Wilck Nicola 
Published: May 2024

Abstract

Background and Aims
High blood pressure is associated with measurable inflammation, which precedes and promotes damage to the heart and kidneys. Microbiome-derived metabolites, particularly indole metabolites, modulate inflammation and host physiology, partially through aryl hydrocarbon receptor (AhR) signaling. To better understand the potential of a microbiome-targeting therapeutic approach to achieve organ protection in hypertension, we used narrow-spectrum antibiotics without enteral absorption to specifically deplete gram-negative or -positive bacteria in double transgenic rats (dTGR).

Method
Four-week-old dTGR (transgenic for human renin and angiotensinogen) were treated with oral Vancomycin (Vanco), Polymyxin B (Poly) or Vehicle (Veh) for 3 weeks. Seven-week-old SD rats were included as healthy controls. Microbiome, clinical and immune phenotype were analyzed by shotgun metagenomic sequencing, echocardiography, telemetric blood pressure (BP) measurement, clinical chemistry, bulk RNAseq and flow cytometry.

Results
Hypertensive kidney damage was ameliorated in Vanco treated dTGR, as assessed by renal Lcn2 expression, blood urea nitrogen and albuminuria. Vanco treated dTGR had significantly decreased cardiac hypertrophy. Poly treatment showed no effect. BP levels for both antibiotic treatments were not significantly different from Veh, despite a significantly improved endothelium-dependent and -independent vasorelaxation in isolated mesenteric arteries in both treated groups. Surprisingly, Vanco treatment led to a massive increase of gram-positive Lactobacilli and associated gene abundance for the production of indole lactic acid (ILA, via araT). We could previously show that ILA inhibits differentiation of pathological Th17 cells through AhR modulation. In line, Vanco treatment reduced the increased number of pathological Th17 in the kidney and intestine of dTGR. Poly treatment did not alter the inflammatory signature.

Conclusion
Modulation of the intestinal microbiome by narrow-spectrum antibiotics affects hypertensive organ damage. Our data underscores the importance of the gut microbiome in modulating hypertensive organ damage and helps to identify potential therapeutic strategies in the microbiome. Ongoing experiments investigate pro- and postbiotic therapeutic approaches and their AhR dependency.
#1838 SGLT2 computational structural studies investigating polypharmacy
Authors: Lloyd Aled , Austin-Muttitt Karl , Mullins Jonathan 
Published: May 2024

Abstract

Background and Aims
Sodium Glucose Cotransporter 2 (SGLT2) is the main active transport protein involved in sodium and glucose reabsorption in the kidney. SGLT2 inhibitors (SGLT2i) are widely recommended for patients with diabetes, heart failure and chronic kidney disease (CKD). Many multimorbid patients will be prescribed these compounds resulting in polypharmacy. We have performed a computational drug repurposing screen to identify other licensed drugs capable of binding at or near the SGLT2i active site aiming to identify compounds that could either compete with SGLT2i or inhibit sodium and glucose transport.

Method
The library of BNF listed compounds was obtained from NCBI PubChem. D-I-TASSER was used to generate monomeric structural models and MODELLER was used to incorporate MAP-17 and empaglifozin from a reference structure (PDB 7VSI). CHARM-GUI was used to insert the protein into a membrane. The centroid of a 5 nanosecond GROMACS molecular dynamics (MD) equilibration was used for docking studies using PLANTS. A bespoke tool was used to identify compounds interacting with key protein residues. CHARM-GUI and bespoke software were used to prepare membrane-bound systems to run in GROMACS using GPU's in Google Colab. 10 nanosecond simulations were undertaken (300 Kelvin and 1 bar) to discriminate between binding and non-binding events.

Results
The SGLT2-MAP17 structure in the inward-open conformation obtained showed good agreement with published structures. Existing SGLT2i (empaglifozin, dapaglifozin, canaglifozin, ertuglifozin) all feature in the top 1% of docked compounds in the repurposing screen. 17 compounds were investigated by MD, with all remaining bound to the protein in simulation. Ceftriaxone, tobramycin, clindamycin, fluvastatin, atorvastatin and ticagrelor were among the compounds with potentially significant interactions.
It is not clear whether the stable ligand interactions identified here would result in inhibition of sodium and glucose transport, or if the interactions might provide competitive inhibition for SGLT2i compounds currently used. The compounds identified have no hitherto recognised interactions with SGLT2i; nor do they result in adverse effects suggesting inhibition of the protein. This study is limited by considering only the protein-ligand interaction and not wider pharmacokinetic or pharmacodynamic factors.

Conclusion
The indication of interactions with several compounds likely to be prescribed alongside SGLT2 inhibitors, such as antibiotics, statins and antiplatelet agents, warrants further investigation of the potential for polypharmacological complications.
#1861 Association of the polymorphisms of the angiotensin converting enzyme and FRMD3 genes in the development of diabetic kidney disease
Authors: Garcia Juan Daniel Diaz 
Published: May 2024

Abstract

Background and Aims
Individual genetic biomarkers, called single nucleotide polymorphisms (SNPs), have been proposed that could represent potential non-invasive markers for the early diagnosis of diabetic kidney disease (DKD), in addition to their association with a characteristic phenotype.

Aim
To determine the association of polymorphisms of the Angiotensin Converting Enzyme and FRMD3 genes with the risk of developing ERD in patients with type 2 diabetes.

Method
Case-control study, comparative, observational, ambispective and cross-sectional, in which men and women, over 18 years of age with T2D with and without ERD and healthy patients, who underwent DNA extraction, participated. genomic and subsequent genotyping, and detection of SNPs by mass spectrometry.

Results
A total of 400 patients participated, 199 men and 201 women, within which they were divided into three groups: 100 patients with type 2 diabetes and ERD confirmed by renal biopsy, 100 patients with type 2 diabetes without ERD and 200 healthy controls.
A total of 3 polymorphisms of the ACE and FRMD3 genes were studied. Among the polymorphisms analyzed in the logistic regression, rs179975 CA (OR, 6.2; 95% CI: 1.15-7.48, p = 0.03), rs1888747 GA (OR, 6.6; 95% CI: 4.60-8.45, p = 0.002) and rs10868025 resulted. CG (OR, 4.1; 95% CI: 2.40-5.60, p = 0.002) Table 1.

Conclusion
Our study demonstrated the association of well-established genetic variants of the ACE and FRMD3 gene polymorphisms with the presence of ERD, showing that these SNPs, specifically rs179975 CA, rs1888747 GA and rs10868025 GC, may represent important genetic markers in the development of ERD and could be a predisposing factor due to the high frequency and strength of association that were observed in our studied population, this being the first study in Latin America.
#1591 Analysis of microvesicles and their relationship with oxidative stress as biomarkers of cardiovascular damage in chronic kidney disease
Authors: Arévalo Gemma Valera , Espada Paula Jara Caro , Alique Matilde , Lozano Claudia Yuste , del Mar Rodriguez San Pedro Maria , Garcia Victor Cabanillas , Rubio Andrea Figuer , Ruiz Enrique Morales , Chamond Manuel Ramírez , Carracedo Julia 
Published: May 2024

Abstract

Background and Aims
Chronic kidney disease (CKD) is associated with a higher incidence of cardiovascular diseases. These diseases are preceded by endothelial dysfunction and alterations in coagulation systems. One of the challenges of research in this field is the search for diagnostic and predictive biomarkers of cardiovascular pathology. Our hypothesis is that endothelial dysfunction and cardiovascular risk could be evidenced by the increased release of endothelial microvesicles (EMVs) and platelet microvesicles (PMVs), as well as a greater expression of tissue factor (TF). We also propose a relationship between the release of microvesicles and the oxidative stress observed in these patients. The aim of the study was to analyze the levels of MVEs and MVPs, the expression of FT and its relationship with pro-oxidant and antioxidant parameters as possible early biomarkers of cardiovascular and thrombotic risk in different stages and treatments of CKD.

Method
It is a cross-sectional study consisted of 116 patients (40 with advanced chronic disease (CKD), 40 undergoing hemodialysis (HD) and 36 undergoing peritoneal dialysis (PD)), as well as 17 healthy subjects (CT). Microvesicle phenotyping was performed by direct immunofluorescence and flow cytometry in plasma isolated by centrifugation from peripheral blood. The analysis of oxidative stress parameters was carried out by spectrophotometry, after isolation of plasma and mononuclear and polymorphonuclear leukocytes by means of a ficoll gradient.

Results
Patients on PD have higher plasma PMVs levels (p = 0.0005 vs ACKD and p = 0,0002 vs HD), while those on HD and PD have higher levels of EMVs compared to ACKD (p = 0,0001 and p = 0,0125, respectively). FT expression in PMVs is lower in HD (p &lt; 0.0001 vs ACKD) and FT expression in EMVs is lower in HD and PD compared to ACKD (p = 0,0004 and p= 0.0033, respectively) (Fig. 1). Patients with CKD have a higher activity of pro-oxidant enzymes (XO, GPx), as well as high levels of lipid peroxidation by-products (TBARS-MDA) and lower activity of antioxidant enzymes (GSH, CAT, SOD) at the plasma and cellular level. A positive relationship has been observed between pro-oxidant parameters and the release of MVP and MVE, as well as the expression of FT (Table 1). Patients with cardiovascular events during the years of follow-up have higher levels of FT expressed in microvesicles, and long-term survival decreases in patients with elevated FT levels.

Conclusion
Patients with CKD have higher plasma levels of PMVs and EMVs and higher FT expression, related to a state of oxidative stress. These parameters could be considered as biomarkers for predicting, diagnosing, and prognostic cardiovascular events in CKD.
#2704 Effects of high dietary salt on immunome and microbiome composition – results from a randomized clinical trial
Authors: Bartolomaeus Hendrik , Anandakumar Harithaa , Chen Chia-Yu , Mähler Anja , Müller Dominik N , Forslund Sofia K , Wilck Nicola 
Published: May 2024

Abstract

Background and Aims
Increased dietary salt intake ranks among the most prominent nutritional risk factors worldwide and has been tied to arterial hypertension and all-cause mortality. The mechanisms responsible are incompletely understood and have recently been extended to include inflammatory and microbiome-associated mechanisms. Building on our preliminary data, the present study investigates whether a moderate increase in salt intake in healthy subjects primes host physiology to a more transiently unstable state, potentially leading to changes in the microbiome-immune axis.

Method
We conducted a prospective, randomized, double-blinded trial to evaluate the effect of high dietary salt in healthy participants (NCT03024567), where the intervention group (n = 19) was given 6 g of salt (NaCl capsules) in addition to the habitual salt intake, resulting in an average doubling of the salt intake recommended by expert societies. A placebo group (n = 19) received gelatin capsules for 14 days. Clinical parameters, fecal samples and PBMC were collected at baseline and day 14. Shotgun metagenomic sequencing, metabolomics (stool and serum), and single-cell sequencing (Cellular Indexing of Transcriptomes and Epitopes by Sequencing (CITEseq)) of whole PBMCs and CD4+ sorted T cells (∼150 k single cells) was performed.

Results
Microbiome analysis confirms previous findings showing an increased dissimilarity of microbiome composition (Jensen-Shannon Divergence) under a high-salt. Differential abundance of the microbiome's functional space, as quantified by functional gut-specific modules, picked up a salt-specific module (M00494, NatK-NatR (sodium extrusion) two-component regulatory system) in the salt intervention group. CITEseq revealed a significant reduction of circulating NK cells and an increase in classical monocytes as well as changes to several T cell subsets. Furthermore, within several immune cell subsets, we detected differently expressed genes (DEGs) solely in the salt group. We found 602 DEG in naïve conventional T cells (Tconv) and 202 DEGs in non-naïve Tconv, e.g. belonging to NF-kB and T cell receptor signaling pathways.

Conclusion
Our placebo-controlled study is the first to utilize different omics techniques to investigate and identify high-salt-induced changes in the microbiome and immunome in healthy individuals that may be relevant for health-to-disease transition.
#1846 Oxalate nephropathy in diabetic kidney disease: another factor to take into account?
Authors: Roldán Deborah , Melero Eva López , Guerrero Maria Carmen , Arcos Hansely , Ocaña Javier , Gruss Enrique , Shabaka Amir 
Published: May 2024

Abstract

Background and Aims
Patients with diabetes mellitus (DM) have an increased urinary excretion of oxalate. Around 40% of patients with oxalate nephropathy have DM. The aim of this study was to describe the prevalence of tubular deposits of calcium oxalate (CaOx) crystals in patients with diabetic kidney disease (DKD) and investigate its association with renal survival.

Method
We performed an observational retrospective study that included patients with DKD in renal biopsies performed at our centre between January 1999 and December 2021. We revised the biopsy specimens for the presence of intratubular CaOx crystals. We excluded patients with a histological findings of non-diabetic kidney disease and those lost to follow-up. Renal survival was defined as a state free from developing end-stage kidney disease (ESKD) requiring renal replacement therapy.

Results
The study included 87 patients with a mean age of 63.1 ± 13 years, 73.5% were male, and 88.5% had type 2 DM (11.5% type 1 DM). Baseline GFR at the moment of kidney biopsy was 38.5 ± 23 ml/min, and baseline median proteinuria was 3.46 (1.35-5.70) g/day. We found intratubular CaOx deposits in 11 biopsies (12.6%). These findings were only found in patients with type 2 DM (14.3% vs 0%), and was more frequently present in patients with a history of renal stones (33.3% vs 11.1%). There were no differences in baseline GFR, proteinuria or vintage of DM between patients with intratubular CaOx deposits and those with no signs of oxalte nephropathy. CaOx deposition was not associated with other histological lesions such as percentage of glomerular sclerosis, grade of interstitial fibrosis and/or tubular atrophy, interstitial inflammation, arterial hyalinosis or arteriosclerosis.
After a median follow-up of 41 months, 49.4% of patients developed ESKD while 26.4% died without progressing to ESKD. The patients who progressed to ESKD had a higher baseline serum creatinine (2.56 ± 1.45 vs 1.98 ± 1.07 ml/min, p = 0.037) and lower serum albumin (3.08 ± 0.70 vs 3.57 ± 0.74 g/dl, p = 0.003). In the regression analysis there was no association between intratubular CaOx deposits and progression to ESKD (OR = 2.96, 95% CI 0.73-12.03). In the adjusted model, no histological lesions were associated with renal survival. In the survival analysis, the presence of intratubular CaOx deposits was not associated with neither renal nor patient survival.

Conclusion
Oxalate nephropathy, defined as the presence of intratubular CaOx deposits in kidney biopsies, may be found in patients with DKD. In our cohort, 14.3% of type 2 DM patients with DKD had concomitant oxalate nephropathy. Its presence was not associated with a worse renal or patient survival.