Pathogenesis Of Chronic Kidney Disease Research Articles

Lactobacillus acidophilus KBL409 protects against kidney injury via improving mitochondrial function with chronic kidney disease.

Recent advances have led to greater recognition of the role of mitochondrial dysfunction in the pathogenesis of chronic kidney disease (CKD). There has been evidence that CKD is also associated with dysbiosis. Here, we aimed to evaluate whether probiotic supplements can have protective effects against kidney injury via improving mitochondrial function. An animal model of CKD was induced by feeding C57BL/6 mice a diet containing 0.2% adenine. KBL409, a strain of Lactobacillus acidophilus, was administered via oral gavage at a dose of 1 × 109CFU daily. To clarify the underlying mechanisms by which probiotics exert protective effects on mitochondria in CKD, primary mouse tubular epithelial cells stimulated with TGF-β and p-cresyl sulfate were administered with butyrate. In CKD mice, PGC-1α and AMPK, key mitochondrial energy metabolism regulators, were down-regulated. In addition, mitochondrial dynamics shifted toward fission, the number of fragmented cristae increased, and mitochondrial mass decreased. These alterations were restored by KBL409 administration. KBL409 supplementation also improved defects in fatty acid oxidation and glycolysis and restored the suppressed enzyme levels involved in TCA cycle. Accordingly, there was a concomitant improvement in mitochondrial respiration and ATP production assessed by mitochondrial function assay. These favorable effects of KBL409 on mitochondria ultimately decreased kidney fibrosis in CKD mice. In vitro analyses with butyrate recapitulated the findings of animal study. This study demonstrates that administration of the probiotic Lactobacillus acidophilus KBL409 protects against kidney injury via improving mitochondrial function.

The correlation between pentraxin-3, matrix metalloproteinase-9, and estimated glomerular filtration rate in patients with chronic kidney disease

Background: Chronic kidney disease (CKD) is diagnosed when there is a sustained decrease in the estimated glomerular filtration rate (EGFR) over a period of more than 3 months. While Pentraxin-3 (PTX-3) and Matrix Metalloproteinase-9 (MMP-9) levels increase during the acute phase of the kidney injury, chronic conditions often exhibit alteration in the epithelial mesenchymal transition (EMT).Objectives: This study aimed to elucidate the correlation between serum PTX-3, MMP-9, and eGFR in patients with CKD. Method: Thirty hypertensive patients with CKD stages 3, 4, and 5, aged between 16 and 65 years, were enrolled in the study (15 males and 15 females). Diagnosis of CKD was based on the 2012 Kidney Disease Improving Global Outcomes (KDIGO) criteria, utilizing serum creatinine, and CKD-epidemiology Collaboration (CKD-EPI) estimates. Subsequently, serum MMP-9 and PTX-3 levels were quantified. Result: Patients with CKD exhibited significantly higher serum levels of PTX3 and MMP9. Furthermore. a significant negative connection between PTX-3, MMP-9, and EGFR was observed. Additionally, CKD patients displayed a correlation between PTX-3 and MMP-9 concentrations.Conclusion: Plasma levels of PTX-3 and MMP-9 serve as unique, promising, and important markers that contribute to the pathogenesis of CKD.

Correlation between Urinary Angiotensinogen (AGT) and Albuminuria in Chronic Kidney Disease (CKD)

Chronic kidney disease (CKD) is a global health concern associated with significant morbidity and mortality. Albuminuria, a hallmark of kidney damage, is a strong predictor of CKD progression and adverse outcomes. Recent research has focused on understanding the correlation between urinary angiotensinogen (AGT) levels, a component of the renin-angiotensin system (RAS), and albuminuria in CKD patients. This review article synthesizes evidence from various studies exploring this correlation and elucidates its mechanistic insights and clinical implications. Clinical studies consistently demonstrate a positive correlation between urinary AGT levels and albuminuria in CKD patients. Elevated urinary AGT levels are associated with increased albuminuria, independent of traditional risk factors, suggesting a potential role for AGT in the pathogenesis of kidney damage and proteinuria in CKD. Mechanistic insights suggest that increased intrarenal RAS activity may lead to enhanced AGT production and secretion, contributing to glomerular hypertension, inflammation, and fibrosis, ultimately promoting albuminuria and CKD progression. The clinical implications of this correlation are profound. Elevated urinary AGT levels may serve as a non-invasive biomarker for assessing intrarenal RAS activity and predicting CKD progression and adverse outcomes. Furthermore, interventions targeting the RAS pathway, such as angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs), may help reduce urinary AGT levels and mitigate albuminuria, offering promising therapeutic opportunities for improving patient outcomes in CKD. In conclusion, the correlation between urinary AGT and albuminuria in CKD represents a complex interplay between renal physiology, RAS activation, and kidney damage. By elucidating this correlation, we gain valuable insights into the pathogenesis of CKD and identify urinary AGT as a potential biomarker and therapeutic target for personalized CKD management. Further research is warranted to validate these findings, explore the clinical utility of urinary AGT measurement, and develop targeted interventions aimed at mitigating albuminuria and slowing CKD progression. Through continued investigation, we can strive to improve outcomes and quality of life for patients living with CKD.

Both partial inactivation as well as activation of NF-κB signaling lead to hypertension and chronic kidney disease.

Activation of NF-κB-signalling is key in the pathogenesis of chronic kidney diseases (CKD). However, a certain level of NF-κB activity is necessary to enable tissue repair. To investigate the relationship between activated and inactivated NF-κB signaling on the pathogenesis of CKD using mouse models of NF-κB partial inactivation (mutating cysteine at position 59 of the sixth exon on the NF-κB gene into alanine) and activation (mutating cysteine at position 59 of the sixth exon on the NF-κB gene into serine). The density of CD3, CD8, CD68 positive cells, as well as the expression of IL-6, TRAF-1, and NAF-1 in the kidney tissues of NF-κBC59A mice were reduced, whereas an opposing pattern was observed in the NF-κBC59S mice. Blood pressure, kidney fibrosis (analyzed by PAS-, Masson trichrome-, and Sirius-Red-staining as well as α-SMA immunofluorescence), serum creatinine and urinary albumin-to-creatinine-ratio are markedly increased in NF-κB activated and inactivated mice compared to controls. Transmission electron microscopy indicated that the glomerular basement membrane was thicker in both NF-κBC59A and NF-κBC59S mice compared to wild-type mice. Using mice models with partially activated and inactivated NF-κB pathways suggests that there is an apparently U-shaped relationship between blood pressure, kidney function as well as morphology and the activation of the NF-κB pathway. A certain optimal activity of the NF-κB pathway seems to be important to maintain optimal kidney function and morphology.

Activation of Pannexin-1 channels causes cell dysfunction and damage in mesangial cells derived from angiotensin II-exposed mice.

Chronic kidney disease (CKD) is a prevalent health concern associated with various pathological conditions, including hypertensive nephropathy. Mesangial cells are crucial in maintaining glomerular function, yet their involvement in CKD pathogenesis remains poorly understood. Recent evidence indicates that overactivation of Pannexin-1 (Panx1) channels could contribute to the pathogenesis and progression of various diseases. Although Panx1 is expressed in the kidney, its contribution to the dysfunction of renal cells during pathological conditions remains to be elucidated. This study aimed to investigate the impact of Panx1 channels on mesangial cell function in the context of hypertensive nephropathy. Using an Ang II-infused mouse model and primary mesangial cell cultures, we demonstrated that in vivo exposure to Ang II sensitizes cultured mesangial cells to show increased alterations when they are subjected to subsequent in vitro exposure to Ang II. Particularly, mesangial cell cultures treated with Ang II showed elevated activity of Panx1 channels and increased release of ATP. The latter was associated with enhanced basal intracellular Ca2+ ([Ca2+]i) and increased ATP-mediated [Ca2+]i responses. These effects were accompanied by increased lipid peroxidation and reduced cell viability. Crucially, all the adverse impacts evoked by Ang II were prevented by the blockade of Panx1 channels, underscoring their critical role in mediating cellular dysfunction in mesangial cells. By elucidating the mechanisms by which Ang II negatively impacts mesangial cell function, this study provides valuable insights into the pathogenesis of renal damage in hypertensive nephropathy.

Changes in the composition of the gut microbiota and content of microbial-derived uremic toxins in patients undergoing hemodialysis

Recent data highlight a significant role of the gut microbiota in the pathogenesis of chronic kidney disease, particularly in its terminal stage. However, little is known about the features of intestinal dysbiosis in people undergoing programed hemodialysis. Changes in the intestinal microbiota and blood levels of uremic toxins of microbial origin in patients with terminal renal insufficiency receiving hemodialysis were analyzed. This cross-sectional study included 80 patients receiving hemodialysis and 20 individuals with normal kidney function. The state of the microbiocenosis of the colon was studied using a polymerase chain reaction with a commercial set Colonoflor 16 (premium) manufactured by Alfalab (Russia). Serum levels of trimethylamine and its metabolite trimethylamine-N-oxide were determined by liquid chromatography/mass spectrometry. The concentrations of indoxyl sulfate and p-cresyl sulfate were evaluated by enzyme immunoassay according to the instructions of a commercial kit. In patients undergoing programed hemodialysis, increased colonization of enterococci was combined with the reduction of lacto and bifidophlora, E. coli, ruminococci, bacteria producing short-chain fatty acids (Faecalibacterium prausnitzii, Eubacterium rectale, Roseburia inulinivorans, and Blautia spp.) and microorganisms involved in maintaining the integrity of the intestinal barrier (Bacteroides thetaomicron and Akkermansia muciniphila). In addition, high titer levels of representatives of opportunistic and even pathogenic flora were often found in this group. Intestinal dysbiosis in patients undergoing programed hemodialysis was accompanied by a significant increase in the concentration of uremic toxins in the blood. Compared with individuals with normal renal function, the trimethylamine level in patients undergoing programed hemodialysis was increased 22 times; trimethylamine-N-oxide, 23 times; indoxyl sulfate, 21 times; and p-cresyl sulfate, 5 times. Thus, patients receiving hemodialysis exhibited pronounced pathological changes in intestinal microbiocenosis, accompanied by a significant increase in serum levels of uremic toxins of microbial origin.

Wnt/β-catenin Pathway Aggravates Renal Fibrosis by Activating PUM2 Transcription to Repress YME1L-mediated Mitochondrial Homeostasis.

Chronic kidney disease (CKD) affects more than 10% of people worldwide and is a leading cause of death. However, the pathogenesis of CKD remains elusive. The oxidative stress and mitochondrial membrane potential were detected using Enzyme-linked immunosorbent assay and JC-1 assay. Co-immunoprecipitation, dual-luciferase assay, chromatin IP, RNA IP and RNA pull-down were used to validate the interactions among genes. Exploiting a H2O2-induced fibrosis model in vitro, PUM2 expression was upregulated in Human kidney 2 cell (HK-2) cells, along with reduced cell viability, enhanced oxidative stress, impaired mitochondrial potential, and upregulated expressions of fibrosis-associated proteins. While PUM2 knockdown reversed the H2O2-induced injury in HK-2 cells. Mechanically, Wnt/β-catenin pathway activated PUM2 transcription via TCF4. It was further identified that Wnt/β-catenin pathway inhibited YME1L expression through PUM2-mediated destabilizing of its mRNA. PUM2 aggravated H2O2-induced oxidative stress, mitochondrial dysfunction, and renal fibrosis in HK-2 cell via suppressing YME1L expression. Our study revealed that Wnt/β-catenin aggravated renal fibrosis by activating PUM2 transcription to repress YME1L-mediated mitochondrial homeostasis, providing novel insights and potential therapeutic targets for the treatment of kidney fibrosis.

Novel cardioprotective and nephroprotective combination in patients with type 2 diabetes and chronic kidney disease: perspectives of use

Chronic kidney disease (CKD) is a common complication of diabetes mellitus. It increases significantly cardiovascular risk and decreases the quality of life. CKD requires treatment, and the treatment paradigm for type 2 diabetes has shifted from a glucose-centric approach towards disease-modifying therapy. Attention is being paid to cardioprotective and nephroprotective effects. In patients with type 2 diabetes and CKD, drugs that affect the renin-angiotensin-aldosterone system, as well as sodium-glucose cotransporter type 2 inhibitors (iSGLT2) are widely used. Despite the proven positive effect of these drugs in preservation of renal functions, the pathogenesis of CKD contains links that have not yet been covered. In particular, the activity of fibrosis processes in the renal parenchyma is increased in patients with CKD due to high expression of mineracorticoid receptors. It may be a potential target for nephroprotective drugs. Thus, mineralocorticoid receptor antagonists (MCRA) may influence the residual risk of CKD progression. In particular, the effectiveness of the non-steroid selective AMCR finerenone has been proven in a number of large clinical studies, which confirmed its nephroprotective potential. In this regard, studies aimed at studying the joint effect of known nephroprotective drugs, as well as their combined effect on cardiovascular risk, are highly needed.This review marks the main mechanisms of the combined action of iSGLT2 and finerenone. Discussion of the results of main clinical studies with combined use of standard nephroprotective therapy, SGLT2 and finerenone is also presented.

Renal effects of GLP-1 receptor agonists and tirzepatide in individuals with type 2 diabetes: seeds of a promising future.

Chronic kidney disease (CKD) is one of the most common complications of type 2 diabetes (T2D), and CKD-related disability and mortality are increasing despite the recent advances in diabetes management. The dual GIP/GLP-1 receptor agonist tirzepatide is among the furthest developed multi-agonists for diabetes care and has so far displayed promising nephroprotective effects. This review aims to summarize the evidence regarding the nephroprotective effects of glucagon-like peptide-1 receptor agonists (GLP-1RA) and tirzepatide and the putative mechanisms underlying the favorable renal profile of tirzepatide. A comprehensive literature search was performed from inception to July 31st 2023 to select research papers addressing the renal effects of GLP-1RA and tirzepatide. The pathogenesis of CKD in patients with T2D likely involves many contributors besides hyperglycemia, such as hypertension, obesity, insulin resistance and glomerular atherosclerosis, exerting kidney damage through metabolic, fibrotic, inflammatory, and hemodynamic mechanisms. Tirzepatide displayed an unprecedented glucose and body weight lowering potential, presenting also with the ability to increase insulin sensitivity, reduce systolic blood pressure and inflammation and ameliorate dyslipidemia, particularly by reducing triglycerides levels. Tirzepatide is likely to counteract most of the pathogenetic factors contributing to CKD in T2D, potentially representing a step forward in incretin-based therapy towards nephroprotection. Further evidence is needed to understand its role in renal hemodynamics, fibrosis, cell damage and atherosclerosis, as well as to conclusively show reduction of hard renal outcomes.

RAS protein activator-like 2 (RASAL2) initiates peritubular capillary rarefaction in hypoxic renal interstitial fibrosis

The progression of chronic kidney disease (CKD) often involves renal interstitial fibrosis (RIF) and subsequent loss of peritubular capillaries (PTCs), which enhances disease severity. Despite advancements in our understanding of fibrosis, effective interventions for reversing capillary loss remain elusive. Notably, RIF exhibits reduced capillary density, whereas renal cell carcinoma (RCC) shows robust angiogenesis under hypoxic conditions. Using RNA sequencing and bioinformatics, we identified differentially expressed genes (DEGs) in hypoxic human renal tubular epithelial cells (HK-2) and renal cancer cells (786-0). Analysis of altered Ras and PI3K/Akt pathways coupled with hub gene investigation revealed RAS protein activator-like 2 (RASAL2) as a key candidate. Subsequent in vitro and in vivo studies confirmed RASAL2′s early-stage response in RIF, which reduced with fibrosis progression. RASAL2 suppression in HK-2 cells enhanced angiogenesis, as evidenced by increased proliferation, migration, and branching of human umbilical vein endothelial cells (HUVECs) co-cultured with HK-2 cells. In mice, RASAL2 knockdown improved Vascular endothelial growth factor A (VEGFA) and Proliferating cell nuclear antigen (PCNA) levels in unilateral ureteral occlusion (UUO)-induced fibrosis (compared to wild type). Hypoxia-inducible factor 1 alpha (HIF-1α) emerged as a pivotal mediator, substantiated by chromatin immunoprecipitation (ChIP) sequencing, with its induction linked to activation. Hypoxia increased the production of RASAL2-enriched extracellular vesicles (EVs) derived from tubular cells, which were internalized by endothelial cells, contributing to the exacerbation of PTC loss. These findings underscore RASAL2′s role in mediating reduced angiogenesis in RIF and reveal a novel EV-mediated communication between hypoxic tubular- and endothelial cells, demonstrating a complex interplay between angiogenesis and fibrosis in CKD pathogenesis.

Renal sinus fat is associated with intrarenal hemodynamic abnormalities independent of visceral fat in patients with chronic kidney disease

ObjectiveObesity is a risk factor of chronic kidney disease (CKD), contributing to the rising incidence of cardiometabolic diseases. Renal sinus fat (RSF) is an ectopic fat depot located at the renal cavity that could impair renal function and hemodynamic through compression of renal structures. The major purpose of this study was to explore the relationship between RSF accumulation and renal dysfunction in CKD patients. MethodsWe evaluated the associations between computed tomography measured RSF volume and key clinical and histologic parameters involved in renal function and hemodynamics in 132 well-characterized CKD patients who underwent renal biopsy (median age: 62 years; 63.6% men). ResultsRSF volume normalized by renal volume (RSF%) positively correlated with obesity-related traits such body mass index and visceral fat volume (VFV) (all P < 0.001) whereas it negatively correlated with estimated glomerular filtration rate (eGFR) (ρ = −0.42, P < 0.001) and 24-h urinary creatinine clearance (CCr) (ρ = −0.34, P < 0.001). Notably, we found robust positive correlations between RSF% and renal resistive index (RRI) measured by the Doppler ultrasound (ρ = 0.40, P < 0.001), and the histological severity of global glomerular sclerosis (ρ = 0.48, P < 0.001) and interstitial fibrosis and tubular atrophy (IFTA) (ρ = 0.35, P < 0.001). In the multivariate linear regression models, after accounting for potential confounders including VFV, RSF% remained significantly associated with CCr (β = −0.26, P < 0.001), RRI (β = 0.17, P = 0.022), global glomerular sclerosis (β = 0.21, P = 0.002), and IFTA (β = 0.17, P = 0.012). ConclusionRSF accumulation is associated with renal dysfunction and hemodynamic abnormalities independent of visceral adiposity. Our results suggest that RSF may have a potential unique role in the pathogenesis of CKD.

Identification of Shared Signature Genes and Immune Microenvironment Subtypes for Heart Failure and Chronic Kidney Disease Based on Machine Learning.

A complex interrelationship exists between Heart Failure (HF) and chronic kidney disease (CKD). This study aims to clarify the molecular mechanisms of the organ-to-organ interplay between heart failure and CKD, as well as to identify extremely sensitive and specific biomarkers. Differentially expressed tandem genes were identified from HF and CKD microarray datasets and enrichment analyses of tandem perturbation genes were performed to determine their biological functions. Machine learning algorithms are utilized to identify diagnostic biomarkers and evaluate the model by ROC curves. RT-PCR was employed to validate the accuracy of diagnostic biomarkers. Molecular subtypes were identified based on tandem gene expression profiling, and immune cell infiltration of different subtypes was examined. Finally, the ssGSEA score was used to build the ImmuneScore model and to assess the differentiation between subtypes using ROC curves. Thirty-three crosstalk genes were associated with inflammatory, immune and metabolism-related signaling pathways. The machine-learning algorithm identified 5 hub genes (PHLDA1, ATP1A1, IFIT2, HLTF, and MPP3) as the optimal shared diagnostic biomarkers. The expression levels of tandem genes were negatively correlated with left ventricular ejection fraction and glomerular filtration rate. The CIBERSORT results indicated the presence of severe immune dysregulation in patients with HF and CKD, which was further validated at the single-cell level. Consensus clustering classified HF and CKD patients into immune and metabolic subtypes. Twelve immune genes associated with immune subtypes were screened based on WGCNA analysis, and an ImmuneScore model was constructed for high and low risk. The model accurately predicted different molecular subtypes of HF or CKD. Five crosstalk genes may serve as potential biomarkers for diagnosing HF and CKD and are involved in disease progression. Metabolite disorders causing activation of a large number of immune cells explain the common pathogenesis of HF and CKD.

Enhanced TRPC3 transcription through AT1R/PKA/CREB signaling contributes to mitochondrial dysfunction in renal tubular epithelial cells in D-galactose-induced accelerated aging mice.

Aging-associated renal dysfunction promotes the pathogenesis of chronic kidney disease. Mitochondrial dysfunction in renal tubular epithelial cells is a hallmark of senescence and leads to accelerated progression of renal disorders. Dysregulated calcium profiles in mitochondria contribute to aging-associated disorders, but the detailed mechanism of this process is not clear. In this study, modulation of the sirtuin 1/angiotensin II type 1 receptor (Sirt1/AT1R) pathway partially attenuated renal glomerular sclerosis, tubular atrophy, and interstitial fibrosis in D-galactose (D-gal)-induced accelerated aging mice. Moreover, modulation of the Sirt1/AT1R pathway improved mitochondrial dysfunction induced by D-gal treatment. Transient receptor potential channel, subtype C, member 3 (TRPC3) upregulation mediated dysregulated cellular and mitochondrial calcium homeostasis during aging. Furthermore, knockdown or knockout (KO) of Trpc3 in mice ameliorated D-gal-induced mitochondrial reactive oxygen species production, membrane potential deterioration, and energy metabolism disorder. Mechanistically, activation of the AT1R/PKA pathway promoted CREB phosphorylation and nucleation of CRE2 binding to the Trpc3 promoter (-1659 to -1648 bp) to enhance transcription. Trpc3 KO significantly improved the renal disorder and cell senescence in D-gal-induced mice. Taken together, these results indicate that TRPC3 upregulation mediates age-related renal disorder and is associated with mitochondrial calcium overload and dysfunction. TRPC3 is a promising therapeutic target for aging-associated renal disorders.

Assessing the effects of tempol on renal fibrosis, inflammation, and oxidative stress in a high-salt diet combined with 5/6 nephrectomy rat model: utilizing oxidized albumin as a biomarker

BackgroundOxidative stress has been implicated in the pathogenesis of chronic kidney disease (CKD), prompting the exploration of antioxidants as a potential therapeutic avenue for mitigating disease progression. This study aims to investigate the beneficial impact of Tempol on the progression of CKD in a rat model utilizing oxidized albumin as a biomarker.MethodsAfter four weeks of treatment, metabolic parameters, including body weight, left ventricle residual weight, kidney weight, urine volume, and water and food intake, were measured. Systolic blood pressure, urinary protein, oxidized albumin level, serum creatinine (Scr), blood urea nitrogen (BUN), 8-OHdG, TGF-β1, and micro-albumin were also assessed. Renal fibrosis was evaluated through histological and biochemical assays. P65-NF-κB was quantified using an immunofluorescence test, while Smad3, P65-NF-κB, and Collagen I were measured using western blot. TNF-α, IL-6, MCP-1, TGF-β1, Smad3, and P65-NF-κB were analyzed by RT-qPCR.ResultsRats in the high-salt diet group exhibited impaired renal function, characterized by elevated levels of blood urea nitrogen, serum creatinine, 8-OHdG, urine albumin, and tubulointerstitial damage, along with reduced body weight. However, these effects were significantly ameliorated by Tempol administration. In the high-salt diet group, blood pressure, urinary protein, and oxidized albumin levels were notably higher compared to the normal diet group, but Tempol administration in the treatment group reversed these effects. Rats in the high-salt diet group also displayed increased levels of proinflammatory factors (TNF-α, IL-6, MCP1) and profibrotic factors (NF-κB activation, Collagen I), elevated expression of NADPH oxidation-related subunits (P65), and activation of the TGF-β1/Smad3 signaling pathway. Tempol treatment inhibited NF-κB-mediated inflammation and TGF-β1/Smad3-induced renal fibrosis signaling pathway activation.ConclusionThese findings suggest that Tempol may hold therapeutic potential for preventing and treating rats undergoing 5/6 nephrectomy. Further research is warranted to elucidate the mechanisms underlying Tempol’s protective effects and its potential clinical applications. Besides, there is a discernible positive relationship between oxidized albumin and other biomarkers, such as 8-OHG, urinary protein levels, mALB, Scr, BUN, and TGF-β1 in a High-salt diet combined with 5/6 nephrectomy rat model. These findings suggest the potential utility of oxidized albumin as a sensitive indicator for oxidative stress assessment.

Mannose and glycine: Metabolites with potentially causal implications in chronic kidney disease pathogenesis.

Chronic Kidney Disease (CKD) represents a global health challenge, with its etiology and underlying mechanisms yet to be fully elucidated. Integrating genomics with metabolomics can offer insights into the putatively causal relationships between serum metabolites and CKD. Utilizing bidirectional Mendelian Randomization (MR), we assessed the putatively causal associations between 486 serum metabolites and CKD. Genetic data for these metabolites were sourced from comprehensive genome-wide association studies, and CKD data were obtained from the CKDGen Consortium. Our analysis identified four metabolites with a robust association with CKD risk, of which mannose and glycine showed the most reliable causal relationships. Pathway analysis spotlighted five significant metabolic pathways, notably including "Methionine Metabolism" and "Arginine and Proline Metabolism", as key contributors to CKD pathogenesis. This study underscores the potential of certain serum metabolites as biomarkers for CKD and illuminates pivotal metabolic pathways in CKD's pathogenesis. Our findings lay the groundwork for potential therapeutic interventions and warrant further research for validation.

Mitochondrial genetic variation and risk of chronic kidney disease and acute kidney injury in UK Biobank participants

Experimental models suggest an important role for mitochondrial dysfunction in the pathogenesis of chronic kidney disease (CKD) and acute kidney injury (AKI), but little is known regarding the impact of common mitochondrial genetic variation on kidney health. We sought to evaluate associations of inherited mitochondrial DNA (mtDNA) variation with risk of CKD and AKI in a large population-based cohort. We categorized UK Biobank participants who self-identified as white into eight distinct mtDNA haplotypes, which were previously identified based on their associations with phenotypes associated with mitochondrial DNA copy number, a measure of mitochondrial function. We used linear and logistic regression models to evaluate associations of these mtDNA haplotypes with estimated glomerular filtration rate by serum creatinine and cystatin C (eGFRCr-CysC, N = 362,802), prevalent (N = 416 cases) and incident (N = 405 cases) end-stage kidney disease (ESKD), AKI defined by diagnostic codes (N = 14,170 cases), and urine albumin/creatinine ratio (ACR, N = 114,662). The mean age was 57 ± 8 years and the mean eGFR was 90 ± 14 ml/min/1.73 m2. MtDNA haplotype was significantly associated with eGFR (p = 2.8E−12), but not with prevalent ESKD (p = 5.9E−2), incident ESKD (p = 0.93), AKI (p = 0.26), or urine ACR (p = 0.54). The association of mtDNA haplotype with eGFR remained significant after adjustment for diabetes mellitus and hypertension (p = 1.2E−10). When compared to the reference haplotype, mtDNA haplotypes I (β = 0.402, standard error (SE) = 0.111; p = 2.7E−4), IV (β = 0.430, SE = 0.073; p = 4.2E−9), and V (β = 0.233, SE = 0.050; p = 2.7E−6) were each associated with higher eGFR. Among self-identified white UK Biobank participants, mtDNA haplotype was associated with eGFR, but not with ESKD, AKI or albuminuria.

Abstract TP292: Chronic Kidney Disease Exacerbates Post-Stroke Cell Death and Inflammatory Mechanisms

Chronic kidney disease (CKD) is an important independent risk factor for stroke. To understand the mechanisms of CKD that exacerbates stroke pathogenesis, we developed a rodent CKD model by feeding adult C57BL/6 mice with adenine. There was a gradual progression of CKD from mild to severe stages between days 7 and 28 identified by a combination of hematological (creatinine, blood urea nitrogen, and total protein) and imaging (MRI, μCT, dual-energy X-ray absorptiometry, and ultrasound) markers. The CKD cohort showed significant vascular fibrosis, collagen deposition, microvascular rarefaction, and tubulointerstitial abnormalities in the kidneys compared to the control. Induction of transient focal ischemia (by MCA occlusion) on day 28 of adenine treatment led to bigger infarcts (estimated by MRI on day 1 of reperfusion) and worsened motor function (assessed by rotarod test and beam walk test on days 1, 3, 7 and 14 of reperfusion) compared with non-CKD control cohort. The CKD group also showed twice higher mortality by day 14 of reperfusion after transient MCAO compared to control. Proteomic profiling showed that pro cell death and inflammatory mechanisms were directly induced in the brain by CKD pathogenesis. Overall, these studies conclude that CKD-induced cell death and inflammatory mechanisms in the brain contribute to severe and disabling stroke.

A novel enzyme-based functional correlation algorithm for multi-omics reveals the potential mechanisms of traditional Chinese medicines: Taking Jian-Pi-Yi-Shen formula as an example

The integrated analysis of host metabolome and intestinal microbiome is an opportunity to explore the complex therapeutic mechanisms of traditional Chinese medicines. Currently, researchers mainly employ various statistical correlation analytical methods to investigate metabolome-microbiome correlations. However, these conventional correlation techniques often focus on statistical correlations and their biological meanings are always ignored, especially the functional relevance between them. Here, we developed a novel enzyme-based functional correlation (EBFC) algorithm to further improve the interpretability and the identified scope of microbe-metabolite correlations based on the conventional Spearman’s analysis. The proposed EBFC algorithm is successfully utilized to reveal the therapeutic mechanisms of Jian-Pi-Yi-Shen (JPYS) formula on the treatment of adenine-induced chronic kidney disease (CKD) rats. JPYS, a TCM formula for treating CKD, has beneficial clinical effects. We tentatively revealed the potential mechanism of JPYS for treating CKD rats from the perspective of the serum metabolome, gut microbiome, and their interactions. Specifically, 11 metabolites and 19 bacterial genera in the CKD rats were significantly regulated to approaching normal status after JPYS treatment, suggesting that JPYS could ameliorate the pathological symptoms of CKD rats by reshaping the disturbed metabolome and gut microbiota. Further correlation analysis between the significantly perturbed metabolites, microbiota, and the related enzymes provided more strong evidence for the study of host metabolism-microbiota interactions and the therapeutic mechanism of JPYS on CKD rats. In conclusion, these findings will help us to deeply understand the pathogenesis of CKD and provide new insights into the therapeutic mechanism of JPYS.

Development of mitochondrial dysfunction and oxidative stress in chronic kidney disease

Finding new pathogenic factors that affect the progression of chronic diseases is an important step in the fight against these diseases. In this review, the causes and role of mitochondrial dysfunction in the pathogenesis of chronic kidney disease (CKD) are considered. In this context, the importance of mitochondria for kidney cells in general and proximal tubule cells in particular, as well as the role of oxidative stress in the pathogenesis of CKD, are also discussed. The causes of mitochondrial dysfunction in CKD and the consequences of the development of pathological conditions as a result of impaired mitochondrial activity are analyzed in detail.

Review of Structural and Functional Anatomy of Kidney in Ayurvedic Literature with Special Reference to Diseases of the Kidney

Description of organs and their treatment in Ayurvedic texts is very brief. In today’s world when the diseases of organs like kidneys, heart, liver, and brain etc., are becoming very common, Ayurvedic practitioners find these descriptions inadequate to treat patients with such diseases. An effort was made to assess whether critical analysis of references related to kidneys in classical Ayurvedic texts provide inputs to an Ayurvedic Practitioner to understand the pathogenesis of Chronic Kidney Disease (CKD). Tantrayukti based interpretation of references of kidneys in classical Ayurvedic texts establishes that kidneys were known to, and are elaborately described in Ayurveda, with their anatomical details such as embryological origin, name, number, relation with other abdominal organs, location etc. They are known by the name of Vrukka, which are the abdominal organs that are two in number and are described as Basti Marma (which includes the kidneys, ureter, and Bladder) for the purpose of diagnosis, prognosis, and treatment of all urine related diseases. Basti Marma is one of the three Maha Marmas i.e., most important vital organs of the body viz., Shiro (~brain), Hridaya (~heart) and Basti (~bladders). Vrukka (kidney) is formed from the nutritious part of Kapha, Meda and Rakta, gives the inputs to the practitioner to consider the metabolism of these factors in diagnosis and treatment of CKD. Physiology of formation of urine is also elaborately described in Ayurveda. The reference of Sushruta which discusses about Sahastrshaha Sukshma mukhani (~ thousands of minute openings invisible to naked eye) where urine is formed resembles the description of glomerular filtration. Formation and processing by Samaana, role of Jathar Agni, Dhatvagni and Bhutagni in formation of Mutra (~urine), storage and excretion at the level of Bladder, by Apaana is defined clearly, and this description is of immense value for practitioners. Relation of Basti Marma to Kleda (~body fluids) and its pathological connection with specific diseases is also evident. Understanding of various factors viz., Kleda (~body fluids), Marma (~vital organs), Prana (~life force), Oja (~vitality), Kalaa (~Internal membranes) Jathar Agni, Dhatvagni, Bhutagni etc., and their role in pathogenesis of CKD provides Vaidyas with inputs to devise the line of treatment of patients suffering from CKD, taking into consideration the individual condition of each patient.