Cardiovascular Calcification Heterogeneity in Chronic Kidney Disease

Endothelial injury is one of the risk factors for the progression of vascular calcification in patients receiving maintenance dialysis

BACKGROUND

Vascular calcification is common and progressive in patients with chronic kidney disease. However, the risk factors associated with the progression of vascular calcification in patients receiving maintenance dialysis have not been fully elucidated. Here, we aimed to evaluate vascular calcification and identify the factors associated with its progression in patients receiving maintenance hemodialysis.

METHODS

This is a prospective longitudinal study that included 374 patients receiving maintenance hemodialysis. The participants received assessments of coronary artery calcification (CAC) and abdominal aortic calcification (AAC), as measured by computed tomography. After the baseline investigation, a 2 years follow-up was performed. We also detected the markers of endothelial injury [E-selectin and soluble intercellular adhesion molecule-1 (sICAM-1)]. Finally, the risk factors affecting the CAC and AAC progression were examined by multivariate logistic regression analysis.

RESULTS

Among 374 patients, the median [interquartile range (IQR)] age was 54.0 (40.0-62.0) years; 59.9% of patients were male. The median (IQR) follow-up time was 1.9 (1.8-2.0) years for all patients. By the end of 2-year follow-up, progression of vascular calcification (including CAC and AAC) was observed in 58.0% of patients. Further, compared with the patients without progression of vascular calcification, the endothelial injury (including E-selectin and sICAM-1) of patients with progression of vascular calcification was markedly enhanced. Moreover, after adjustment for the confounders, endothelial injury was a risk factor for the progression of vascular calcification.

CONCLUSION

The present study indicated that endothelial injury is one of the risk factors for the progression of vascular calcification in patients receiving maintenance hemodialysis.

The m6A reader YTHDF2 protects vascular smooth muscle cells against the osteogenic differentiation through targeting Runx2

Vascular calcification (VC) is an important pathological development progress in chronic kidney disease (CKD) and may increase mortality but lacks effective treatments. N6-methyladenosine (m6A) has been verified to be the most prevalent internal chemical RNA modification in mammalian mRNAs. The M6A-modified mRNA degradation process is mediated by the reader YTHDF2 in an m6A-dependent manner. Nevertheless, the exact role and molecular mechanism of YTHDF2 in VC remain unclear. This study aimed to investigate the potential role of YTHDF2 in the osteogenic differentiation of vascular smooth muscle cells (VSMCs). It was found that YTHDF2 was markedly downregulated in both in vivo and in vitro calcified models. Functionally, YTHDF2 plays a protective role in VC. The overexpression of YTHDF2 inhibited the transdifferentiation of VSMCs from a contractile to an osteogenic phenotype, thus decreasing the expression of mineralization regulatory proteins and calcium deposition. Conversely, YTHDF2 deficiency aggravated this process. At the mechanistic level, YTHDF2 suppressed osteogenic transdifferentiation of VSMCs by regulating the Runt-related transcription factor 2 (Runx2). RNA immunoprecipitation-qPCR (RIP-qPCR) confirmed the binding of YTHDF2 to Runx2, and luciferase reporter assays confirmed the presence of the m6A site in Runx2. In addition, an actinomycin D assay showed that the half-life of Runx2 mRNA was dramatically shortened in VSMCs overexpressing YTHDF2. These results suggest that YTHDF2 directly binds to the m6A modification site of Runx2 to mediate the mRNA degradation that prevents VC by inhibiting the osteogenic development of VSMCs. Therefore, YTHDF2 can be considered a potential therapeutic target for managing VC.

Extracellular matrix in vascular homeostasis and disease

The extracellular matrix is an essential component and constitutes a dynamic microenvironment of the vessel wall with an indispensable role in vascular homeostasis and disease. From early development through to ageing, the vascular extracellular matrix undergoes various biochemical and biomechanical alterations in response to diverse environmental cues and exerts precise regulatory control over vessel remodelling. Advances in novel technologies that enable the comprehensive evaluation of extracellular matrix components and cell-matrix interactions have led to the emergence of therapeutic strategies that specifically target this fine-tuned network. In this Review, we explore various aspects of extracellular matrix biology in vascular development, disorders and ageing, emphasizing the effect of the extracellular matrix on disease initiation and progression. Additionally, we provide an overview of the potential therapeutic implications of targeting the extracellular matrix microenvironment in vascular diseases.

Association of serum Klotho and fibroblast growth factor-23 levels with vascular calcification severity in patients with chronic kidney disease: an observational cohort study

PURPOSE

In patients with chronic kidney disease (CKD), vascular calcification (VC) is common and influences patient's outcome and prognosis. However, evaluation methods for VC severity are limited. Klotho and fibroblast growth factor-23 (FGF-23) are biomarkers associating with VC development. This study aimed to explore the association of serum Klotho and FGF-23 levels with VC severity in patients with non-dialysis CKD.

METHODS

Patients with non-dialysis CKD were enrolled during hospitalization and were divided into the following four groups on the basis of their coronary artery calcification (CAC) scores: non-VC (CAC scores = 0), mild VC (0 < CAC scores ≤ 100), moderate VC (100 < CAC scores ≤ 400), and severe VC groups (CAC scores > 400). Serum Klotho and FGF-23 levels among the different groups were compared.

RESULTS

A total of 154 non-dialysis CKD patients were enrolled. Correlation analysis showed that serum FGF-23 level (rho = 0.185, p = 0.022) was positively correlated with VC severity, whereas serum Klotho level (rho =  -  0.196, p = 0.015) was negatively correlated with VC severity in patients with CKD. Multivariable regression analysis showed that Klotho level [odd ratio (OR) = 0.998, 95% confidence interval (CI) 0.996-0.999, p = 0.001] served as a protective factor for VC severity in patients with CKD, whereas FGF-23 level (OR = 1.005, 95% CI 1.001-1.009, p = 0.020) was identified as risk factor for VC severity.

CONCLUSION

Serum Klotho and FGF-23 levels are potential predictors of VC severity in patients with non-dialysis CKD.

Advances in Pathophysiological Mechanisms of Degenerative Aortic Valve Disease

Degenerative aortic valve disease (DAVD) represents the most prevalent valvular ailment among the elderly population, which significantly impacts their physical well-being and potentially poses a lethal risk. Currently, the underlying mechanisms of DAVD remain incompletely understood. While the progression of this disease has traditionally been attributed to degenerative processes associated with aging, numerous recent studies have revealed that heart valve calcification may represent a response of valve tissue to a specific initiating factor, involving the interaction of various genes and signaling pathways. This calcification process is further influenced by a range of factors, including genetic predispositions, environmental exposures, metabolic factors, and hemodynamic considerations. Based on the identification of its biomarkers, potential innovative therapeutic targets are proposed for the treatment of this complex condition. The present article primarily delves into the underlying pathophysiological mechanisms and advancements in diagnostic and therapeutic modalities pertaining to this malady.

Uric acid promotes aortic valve calcification via mediating valve interstitial cell osteogenic differentiation and endothelial dysfunction

Aortic valve calcification is a lethal valvular heart disease lacking effective drug therapy. However, whether uric acid is involved in the development of aortic valve calcification is unclear. Two-sample Mendelian randomization (MR) analyses confirmed the causal relationship between uric acid and valvular heart disease. Uric acid levels were assessed in aortic valve tissue from patients with/without aortic valve calcification. To investigate the impact of hyperuricemia on aortic valve calcification, apolipoprotein E knockout (ApoE-/-) mice fed a high-fat diet (HFD) were also given an adenine diet, with some receiving allopurinol in their drinking water. RNA sequencing was performed on valve interstitial cells (VICs) and endothelial cells (VECs) with/without uric acid. MR analysis has revealed a causal effect of uric acid levels on valvular heart disease. Furthermore, our clinical data indicate a positive correlation between elevated serum uric acid levels and aortic valve calcium score. Specifically, uric acid levels were upregulated in calcified valves. In ApoE-/- mice, an adenine-diet-induced hyperuricemia accelerated aortic valve calcification. RNA sequencing analysis demonstrated that uric acid-promoted osteogenic differentiation, primarily through the activation of hypoxia-inducible factor-1alpha (HIF-α). Additionally, uric acid impaired endothelial barrier function by activating HIF-α, resulting in increased macrophage infiltration in ApoE-/- mice. Inhibiting HIF-1α suppressed osteogenic differentiation and reduced endothelial injury both in vitro and in vivo in the presence of uric acid. This study reveals a new role of hyperuricemia in aortic valve calcification, suggesting uric acid-lowering drugs or HIF-1α inhibition as potential treatments for associated aortic valve calcification.

Vascular inflammation in chronic kidney disease: the role of uremic toxins in macrophage activation

Chronic kidney disease (CKD) is a progressive condition characterized by the gradual loss of kidney function, leading to the accumulation of uremic toxins in the bloodstream. These toxins play a pivotal role in mediating vascular inflammation, a key contributor to the high cardiovascular morbidity and mortality observed in CKD patients. This review article explores the intricate mechanisms by which uremic toxins accelerate vascular inflammation. Macrophages, as versatile immune cells, are central to the inflammatory response. Evidence suggests that the uremic milieu influences macrophage biology. In this review article, we focus on the signaling through which uremic toxins, particularly indoxyl sulfate-an independent risk factor for cardiovascular complications in CKD patients, modulate macrophage activation and function, and how these changes contribute to vascular inflammation, leading to the increased cardiovascular risk. Investigation of such mechanisms provide molecular bases for the development of new therapies that retard the development of cardiovascular disorders in CKD patients.

GLSP mitigates vascular aging by promoting Sirt7-mediated Keap1 deacetylation and Keap1-Nrf2 dissociation

Background and Purpose: Vascular aging is a prior marker of human aging and a significant contributor to atherosclerosis and vascular calcification. However, there are limited pharmacological options available to mitigate vascular aging. Thus, understanding the mechanisms underlying vascular aging and age-related atherosclerosis and vascular calcification is crucial. This study investigates the targets of vascular aging and elucidates the role and mechanisms of Ganoderma lucidum spore powder (GLSP) in mitigating vascular aging and aging-associated atherosclerosis as well as vascular calcification. Methods: The anti-vascular aging effects of GLSP was determined in aged C57BL/6J mice and the targets of GLSP was identified through transcriptome sequencing. Additionally, the protective effects of GLSP on the aged vasculature were assessed by examining atherosclerosis in apoE-/- mice and vascular calcification in VD3 and nicotine-induced mice. In vitro, the protective effects of GLSP triterpenes against vascular aging and calcification was determined in vascular smooth muscle cells (VSMCs). Results: GLSP exerted anti-vascular aging effects by regulating the cell cycle and senescence-associated secretory phenotype (SASP), mitigating DNA damage, reducing oxidative stress, improving mitochondrial function and modulating metabolic levels. Furthermore, GLSP improved vascular aging-associated atherosclerosis and vascular calcification in vivo. Mechanistically, RNA sequencing revealed an upregulation of Sirt7 expression after GLSP treatment. Sirt7 inhibitor exacerbated VSMCs senescence and calcification in senescent VSMCs and abolished the anti-senescence and the inhibitory effect of GLSP triterpenes on VSMCs senescence and calcification. Innovatively, we found that Sirt7 interacted with Keap1 and facilitated Keap1 deacetylation, which promoted Keap1-Nrf2 dissociation and consequently enhanced Nrf2 nuclear translocation and activation. Conclusion: GLSP alleviates vascular aging by exerting antioxidant effects through the activation of the Sirt7-Nrf2 axis, providing a promising new strategy for delaying vascular aging, atherosclerosis and vascular calcification.

Bibliometric analysis of treatment modalities in calcific aortic valve stenosis

Background

Calcific aortic valve stenosis (CAVS) is a common cardiovascular condition associated with significant adverse events and high mortality rates. Unfortunately, there are currently no effective pharmacological treatments to halt or prevent its progression. Through our analysis of global trends and treatment strategies, we have identified valuable insights and promising therapeutic possibilities. Additionally, by utilizing bibliometric and visualization techniques, we provide a comprehensive overview of the current research landscape in this field.

Method

According to our design idea, we used the Web of Science database to select publications on aortic stenosis and related treatments. Through our VOSviewer and CiteSpace analysis, a total of 787 articles have been analyzed by September 2024. We also summarize and explore the most prolific authors, the most prolific countries, and the journals and institutions that publish the most articles.

Results

A visual analysis of the collected articles reveals that Canada and the United States have the highest publication volumes in this field. Among institutions, Harvard University in the U.S. leads in publication count, followed by Laval University in Canada and the University of California in the U.S. The top three research hotspots are stenosis, calcification, and progression. The journal with the highest number of publications in this area is Frontiers in Cardiovascular Medicine, followed by Catheterization and Cardiovascular Interventions and Arteriosclerosis, Thrombosis and Vascular Biology. Furthermore, research on CAVS treatment spans various directions and focuses, including therapeutic approaches, pathogenesis, and diagnostic methods.

Conclusion

Research into CAVS treatment has advanced significantly over the years. While interventional and surgical valve replacement remains the mainstay treatments for aortic stenosis, they are insufficient to fully meet the needs of the patient. Emerging priorities now focus on improving diagnostics, exploring innovative therapies, uncovering disease mechanisms, and developing novel drugs. These findings highlight the evolving demands in this field and underscore the need for continued research to address these challenges.

Transcriptome Reveals the Promoting Effect of Beta-Sitosterol on the Differentiation of Bovine Preadipocytes

Natural small molecule compounds play crucial roles in regulating fat deposition. Beta-sitosterol exhibits multiple biological activities such as cholesterol reduction and anticancer effects. However, its regulatory mechanism in the differentiation of bovine preadipocytes remains unclear. We identified potential associations of Beta-sitosterol with biological processes such as cholesterol regulation and lipid metabolism through the prediction of its targets. We utilized techniques such as Oil Red O staining, Western blotting, RNA-seq, and others to elucidate the promoting effect of Beta-sitosterol on the differentiation of bovine preadipocytes. Furthermore, reducing the expression of the most downregulated gene among differential expressed genes (DEGs), MGP, promotes the differentiation of bovine preadipocytes. After interfering with MGP, RNA-seq analysis on the sixth day of differentiation revealed that DEGs were most significantly enriched in the PPAR signaling pathway. In this pathway, the expression levels of genes related to adipocyte differentiation, including CD36, RXRα, RXRγ, FABP4, PLIN1, ADIPO, and CAP, were significantly upregulated (P < 0.01). Western blot and ELISA analysis on genes related to the PPAR signaling pathway showed that interfering with MGP increased the expression of proteins such as RXRα, indicating the possible activation of the PPAR signaling pathway. In summary, Beta-sitosterol may promote the differentiation of bovine preadipocytes by reducing the expression of MGP, thereby activating the PPAR signaling pathway.

Correlation of Vascular Calcification With Frailty and Quality of Life in Chronic Kidney Disease Stage 4 and 5 Non-dialysis Patients

AIM

Vascular calcification (VC) is known to be associated with higher cardiovascular risk in chronic kidney disease (CKD). However, its impact on morbidity factors like frailty and quality of life is understudied. This study aims to address this gap by assessing the correlation of VC with frailty and quality of life.

METHODS

Consecutive patients with CKD stage 4 and 5, not on dialysis, were enrolled over one year. Pregnant patients and renal transplant recipients were excluded. VC was assessed using lateral abdominal radiographs, echocardiography, and cardiac computed tomography scans. Frailty was assessed using the Fried frailty phenotype. A Kidney Disease Quality of Life-36 (KDQoL-36TM) questionnaire was used for quality-of-life assessment which included physical, mental, and kidney disease-related components. We then investigated the relationships between VC, laboratory parameters, quality of life, and frailty.

RESULTS

A total of 202 patients were enrolled, of which, 26% of patients had detectable VC. Older age, smoking, and coronary artery disease were associated with higher prevalence of VC. Stage of CKD or mineral bone disease markers did not show any significant difference between patients with and without VC. Individuals with VC were significantly more likely to be frail than those without (57.4% vs 30.4%, p-value- 0.001). Patients with VC had significantly lower quality of life scores as compared to those without VC (physical component scores - 45.84±18.98 vs 62.34±22.06; mental component scores - 51.18±20.17 vs 65.99±23.75; kidney disease component scores - 64.90±13.65 vs 74.28±16.32, p-value <0.001).

CONCLUSION

Patients with VC showed higher prevalence of frailty and significantly impaired quality of life. This highlights the profound clinical implications of VC on functional decline in CKD patients.

Evaluation of Individual Cardiovascular Risk in Pre-Dialysis CKD Patients by Using the Ratio of Calcium-Phosphorus Product to Estimated Glomerular Filtration Rate (Ca × P/eGFR)

BACKGROUND

Chronic kidney disease (CKD) patients have an increased risk of cardiovascular disease (CVD), necessitating effective risk assessment methods. This study evaluates the calcium-phosphorus product (Ca × P) to estimated glomerular filtration rate (Ca × P/eGFR) ratio as a potential biomarker for predicting CV risk in pre-dialysis CKD patients.

METHODS

Eighty-four CKD patients in stages G1-G4, according to the KDIGO criteria, were classified into CVD (n = 43) and non-CVD (n = 41) groups. Biochemical parameters, including serum creatinine (SCr), blood urea nitrogen (BUN), calcium (Ca), inorganic phosphate (Pi), parathyroid hormone (PTH), alkaline phosphatase (ALP), Ca × P, eGFR, and the Ca × P/eGFR ratio, were measured and calculated. Statistical analyses were performed to identify predictors of CV risk and evaluate the diagnostic reliability of the Ca × P/eGFR ratio for predicting the risk.

RESULTS

Significant differences were observed in SCr, BUN, eGFR (p < 0.001), and the Ca × P/eGFR ratio (p = 0.007) between the groups. Regression analysis indicated the Ca × P/eGFR ratio as a significant CVD risk predictor (p = 0.012, OR = 1.206, 95% CI: 1.042-1.395). Receiver Operating Characteristic (ROC) curve analysis revealed an AUC of 0.751 (p < 0.001, 95% CI: 0.645-0.857), with a sensitivity and specificity of the method of 74.4% and 70.7%, respectively. Significant correlations were found between the Ca × P/eGFR ratio and SCr, BUN, UA, Ca, Pi, PTH, and ALP.

CONCLUSIONS

The Ca × P/eGFR ratio may serve as a significant predictor of CVD risk in pre-dialysis CKD patients, suggesting that its integration into routine evaluations could enhance CV risk stratification and management.

Sinomenine attenuates uremia vascular calcification by miR-143-5p

Vascular calcification is considered to be a killer of the cardiovascular system, involved inflammation and immunity. There is no approved therapeutic strategy for the prevention of vascular calcification. Sinomenine exhibited anti-inflammatory and immunosuppressive effects. Objective of this study was to investigate the effect of sinomenine in vascular calcification and its potential molecular mechanism. Adenine-induced uremic rats were constructed and administrated with sinomenine. Optical clearing of aortas, alizarin red staining, von Kossa staining, calcification quantification, micro-CT analyses of vascular calcification were performed to analyze calcification in aortas. Administration of 40 mg/kg/d sinomenine effectively alleviated vascular calcification in uremic rats. The miRNA sequencing revealed differentially expressed miRNAs in aortas and bioinformatic analysis assisted with miRNA screening. We screened 9 differential expressed miRNAs and their predicted target genes. By qRT-PCR, we validated that the expression of rno-miR-143-5p was corresponding to our prediction. Sinomenine inhibited vascular smooth muscle cells (VSMCs) calcification, accompanied with miR-143-5p upregulation. MiR-143-5p mimic decreased VSMCs calcification in high phosphate condition. On the contrary, miR-143-5p inhibitor increased VSMCs calcification in high phosphate condition, which was inhibited by sinomenine. In chronic kidney disease patients with vascular calcification, the expression level of circulating miR-143-5p was lower than those without vascular calcification. Sinomenine significantly inhibited vascular calcification in VSMCs and uremic rat. MiR-143-5p was one of the collection of miRNAs modified by sinomenine in vascular calcification. Reduction of miR-143-5p in VSMCs was not only a concomitant phenomenon in pro-calcification condition but also contribute to VSMCs calcification. Circulating miR-143-5p was supposed to be a potential biomarker for vascular calcification in chronic kidney disease patients. In conclusion, sinomenine effectively alleviated vascular calcification, which was attributed to miR-143-5p regulation partly.

4-Octyl itaconate inhibits vascular calcification partially via modulation of HMOX-1 signaling

Vascular calcification frequently occurs in patients with chronic conditions such as chronic kidney disease (CKD), diabetes, and hypertension and represents a significant cause of cardiovascular events. Thus, identifying effective therapeutic targets to inhibit the progression of vascular calcification is essential. 4-Octyl itaconate (4-OI), a derivative of itaconate, exhibits anti-inflammatory and antioxidant activity, both of which play an essential role in the progression of vascular calcification. However, the role and molecular mechanisms of 4-OI in vascular calcification have not yet been elucidated. In this study, we investigated the effects of exogenous 4-OI on vascular calcification using vascular smooth muscle cells (VSMCs), arterial rings, and mice. Alizarin red staining and western blot revealed that 4-OI inhibited calcification and osteogenic differentiation of human VSMCs. Similarly, 4-OI inhibited calcification of rat and human arterial rings and VitD3-overloaded mouse aortas. Mechanistically, RNA sequencing analysis revealed that 4-OI treatment is most likely to affect heme oxygenase 1 (HMOX-1) mRNA expression. The study demonstrated that 4-OI treatment increased HMOX-1 mRNA and protein levels, but suppressed inflammation and oxidative stress in VSMCs under osteogenic conditions. Moreover, HMOX-1 knockdown by siRNA or treatment with the HMOX-1 inhibitor ZnPP9 significantly reversed the suppression effect on calcification of VSMCs and aortas of VitD3-overloaded mice by 4-OI. Furthermore, HMOX-1 knockdown by siRNA markedly abrogated the inhibitory effect of 4-OI on inflammation in VSMCs. These findings suggest that 4-OI alleviates vascular calcification and inhibits oxidative stress and inflammation through modulation of HMOX-1, indicating its potential as a therapeutic target for vascular calcification.

Gla-Rich Protein Is Associated with Vascular Calcification, Inflammation, and Mineral Markers in Peritoneal Dialysis Patients

Background/Objectives: Vascular calcification (VC) is a crucial risk factor for cardiovascular diseases (CVD), particularly in chronic kidney disease (CKD) populations. However, the specific relationship between VC and end-stage renal disease (ESRD) patients undergoing peritoneal dialysis (PD) remains to be fully understood. The identification of new biomarkers to improve VC diagnosis and monitoring would significantly impact cardiovascular risk management in these high-risk patients. Gla-rich protein (GRP) is a VC inhibitor and an anti-inflammatory agent and thus is a potential VC marker in CKD. Here we explored the potential role of GRP as a marker for CVD and investigated the impact of VC in 101 PD patients. Methods: Circulating total Gla-rich protein (tGRP) was quantified in serum and in 24 h dialysate samples. VC score (VCS) was determined using the Adragão method. Results: Serum tGRP was negatively associated with VCS, serum calcium (Ca), phosphate (P), and high-sensitivity C-reactive protein (hsCRP), while it was positively associated with magnesium (Mg). A total of 35.6% of PD patients presented with extensive calcifications (VCS ≥ 3), and the lowest tGRP serum levels were present in this group (419.4 ± 198.5 pg/mL). tGRP in the 24 h dialysate was also negatively associated with VCS and with serum Ca and P. Moreover, serum Ca, P, and VCS were identified as independent determinants of serum tGRP levels. Conclusions: The association of serum tGRP with VC, mineral, and inflammation markers reinforces its potential use as a novel VC biomarker in CKD patients undergoing PD.

Understanding Vascular Calcification in Chronic Kidney Disease: Pathogenesis and Therapeutic Implications

Vascular calcification (VC) is a biological phenomenon characterized by an accumulation of calcium and phosphate deposits within the walls of blood vessels causing the loss of elasticity of the arterial walls. VC plays a crucial role in the incidence and progression of chronic kidney disease (CKD), leading to a significant increase in cardiovascular mortality in these patients. Different conditions such as age, sex, dyslipidemia, diabetes, and hypertension are the main risk factors in patients affected by chronic kidney disease. However, VC may occur earlier and faster in these patients if it is associated with new or non-traditional risk factors such as oxidative stress, anemia, and inflammation. In chronic kidney disease, several pathophysiological processes contribute to vascular calcifications, including osteochondrogenic differentiation of vascular cells, hyperphosphatemia and hypercalcemia, and the loss of specific vascular calcification inhibitors including pyrophosphate, fetuin-A, osteoprotegerin, and matrix GLA protein. In this review we discuss the main traditional and non-traditional risk factors that can promote VC in patients with kidney disease. In addition, we provide an overview of the main pathogenetic mechanisms responsible for VC that may be crucial to identify new prevention strategies and possible new therapeutic approaches to reduce cardiovascular risk in patients with kidney disease.

Causal associations between kidney function and aortic valve stenosis: a bidirectional Mendelian randomization analysis

BACKGROUND

Aortic valve stenosis (AVS) is currently the most common heart valve disease. The results of observational studies on the incidence of AVS in the renal dysfunction population are contradictory due to the short follow-up period and different diagnostic criteria, etc. This study aimed to explore the causal relationship between kidney function and AVS using Mendelian randomization (MR) analysis.

METHODS

We acquired summary statistics of estimated glomerular filtration rate (eGFR) and chronic kidney disease (CKD) from the CKDGen Consortium and a study on AVS from the FinnGen biobank. Univariate and multivariable MR analyses were conducted to evaluate the causal associations. The MR-Egger intercept and MR-PRESSO Global test were applied to assess the pleiotropic effects. The heterogeneity of MR results was tested by Cochran's Q statistic. Moreover, the Bonferroni and FDR corrections were performed for multiple tests.

RESULTS

Genetically predicted decreased eGFR may be associated with a raised risk of AVS (OR = 0.045, p = 1.317e-04 by IVW; OR = 0.002, p = 0.004 by MR-Egger, OR = 0.091, p = 0.057 by WM). The causal association still established after multiple comparisons. Quality control analyses indicated the absence of heterogeneity and pleiotropy in our MR research. In addition, the causality of eGFR and AVS remained significant in multivariable MR analysis after adjusting BMI, hypertension, T2DM, LDL-C, and smoking.

CONCLUSION

Our MR study discovered that reduced eGFR may be a causative risk factor for AVS. In addition, the evidence did not support a significant causal association of AVS on kidney function.

Adenine-induced animal model of chronic kidney disease: current applications and future perspectives

Chronic kidney disease (CKD) with high morbidity and mortality all over the world is characterized by decreased kidney function, a condition which can result from numerous risk factors, including diabetes, hypertension and obesity. Despite significant advances in our understanding of the pathogenesis of CKD, there are still no treatments that can effectively combat CKD, which underscores the urgent need for further study into the pathological mechanisms underlying this condition. In this regard, animal models of CKD are indispensable. This article reviews a widely used animal model of CKD, which is induced by adenine. While a physiologic dose of adenine is beneficial in terms of biological activity, a high dose of adenine is known to induce renal disease in the organism. Following a brief description of the procedure for disease induction by adenine, major mechanisms of adenine-induced CKD are then reviewed, including inflammation, oxidative stress, programmed cell death, metabolic disorders, and fibrillation. Finally, the application and future perspective of this adenine-induced CKD model as a platform for testing the efficacy of a variety of therapeutic approaches is also discussed. Given the simplicity and reproducibility of this animal model, it remains a valuable tool for studying the pathological mechanisms of CKD and identifying therapeutic targets to fight CKD.

Estimated versus measured aortic stiffness: implications of diabetes, chronic kidney disease, sex and height

BACKGROUND

Aortic stiffness is measured by carotid-femoral pulse wave velocity (PWV), but it can also be estimated (ePWV) based on age and brachial mean arterial pressure (MAP). However, diabetes mellitus and/or chronic kidney disease (DM/CKD) may cause more pronounced damage to the arterial wall, changing the pressure and PWV relationship. Furthermore, sex and height could affect PWV through their relationship to the arterial diameter and path length. The aim of the present study was to quantify the extent to which DM/CKD, sex and height affect the validity of ePWV in predicting PWV.

METHODS

This cross-sectional study evaluated PWV in adult participants at high risk of aortic stiffness, using Complior and the second derivative transit time algorithm (PWV 2nd ). PWV 2nd was converted into intersecting tangent PWV (PWV ITc ), and ePWV was calculated using the Reference Values for Arterial Stiffness Collaboration formulas.

RESULTS

Among 825 patients (62% males), the mean age was 60 ± 17 years, 34% had diabetes mellitus, 69% had CKD, and 24% did not have DM/CKD. MAP, ePWV, PWV 2nd , and PWV ITc were, respectively, 96 ± 14 mmHg, 9.8 (8.1-11.8) m/s, 9.5 (7.8-11.9) m/s and 11.3 (8.8-15.9) m/s. There was a significant interaction between DM/CKD, sex, and the predictive value of ePWV. Increasing height lowered the intercept but did not affect the slope of the relationship between estimated and measured PWVs.

CONCLUSION

These findings suggest that the current ePWV equations do not accurately predict PWV in patients with DM/CKD, and that sex and height should also be considered in the future ePWV equations.

Sirt7 protects against vascular calcification via modulation of reactive oxygen species and senescence of vascular smooth muscle cells

Vascular calcification is frequently seen in patients with chronic kidney disease (CKD), and significantly increases cardiovascular mortality and morbidity. Sirt7, a NAD+-dependent histone deacetylases, plays a crucial role in cardiovascular disease. However, the role of Sirt7 in vascular calcification remains largely unknown. Using in vitro and in vivo models of vascular calcification, this study showed that Sirt7 expression was significantly reduced in calcified arteries from mice administered with high dose of vitamin D3 (vD3). We found that knockdown or inhibition of Sirt7 promoted vascular smooth muscle cell (VSMC), aortic ring and vascular calcification in mice, whereas overexpression of Sirt7 had opposite effects. Intriguingly, this protective effect of Sirt7 on vascular calcification is dependent on its deacetylase activity. Unexpectedly, Sirt7 did not alter the osteogenic transition of VSMCs. However, our RNA-seq and subsequent studies demonstrated that knockdown of Sirt7 in VSMCs resulted in increased intracellular reactive oxygen species (ROS) accumulation, and induced an Nrf-2 mediated oxidative stress response. Treatment with the ROS inhibitor N-acetylcysteine (NAC) significantly attenuated the inhibitory effect of Sirt7 on VSMC calcification. Furthermore, we found that knockdown of Sirt7 delayed cell cycle progression and accelerated cellular senescence of VSMCs. Taken together, our results indicate that Sirt7 regulates vascular calcification at least in part through modulation of ROS and cellular senescence of VSMCs. Sirt7 may be a potential therapeutic target for vascular calcification.

In Vitro Models of Cardiovascular Calcification

Cardiovascular calcification, characterized by hydroxyapatite deposition in the arterial wall and heart valves, is associated with high cardiovascular morbidity and mortality. Cardiovascular calcification is a hallmark of aging but is frequently seen in association with chronic diseases, such as chronic kidney disease (CKD), diabetes, dyslipidemia, and hypertension in the younger population as well. Currently, there is no therapeutic approach to prevent or cure cardiovascular calcification. The pathophysiology of cardiovascular calcification is highly complex and involves osteogenic differentiation of various cell types of the cardiovascular system, such as vascular smooth muscle cells and valve interstitial cells. In vitro cellular and ex vivo tissue culture models are simple and useful tools in cardiovascular calcification research. These models contributed largely to the discoveries of the numerous calcification inducers, inhibitors, and molecular mechanisms. In this review, we provide an overview of the in vitro cell culture and the ex vivo tissue culture models applied in the research of cardiovascular calcification.

Small Charged Molecule-Mediated Fibrillar Mineralization: Implications for Ectopic Calcification

Numerous small biomolecules exist in the human body and play roles in various biological and pathological processes. Small molecules are believed not to induce intrafibrillar mineralization alone. They are required to work in synergy with noncollagenous proteins (NCPs) and their analogs, e.g. polyelectrolytes, for inducing intrafibrillar mineralization, as the polymer-induced liquid-like precursor (PILP) process has been well-documented. In this study, we demonstrate that small charged molecules alone, such as sodium tripolyphosphate, sodium citrate, and (3-aminopropyl) triethoxysilane, could directly mediate fibrillar mineralization. We propose that small charged molecules might be immobilized in collagen fibrils to form the polyelectrolyte-like collagen complex (PLCC) via hydrogen bonds. The PLCC could attract CaP precursors along with calcium and phosphate ions for inducing mineralization without any polyelectrolyte additives. The small charged molecule-mediated mineralization process was evidenced by Cryo-TEM, AFM, SEM, FTIR, ICP-OES, etc., as the PLCC exhibited both characteristic features of collagen fibrils and polyelectrolyte with increased charges, hydrophilicity, and density. This might hint at one mechanism of pathological biomineralization, especially for understanding the ectopic calcification process.

Post-translational modifications in kidney diseases and associated cardiovascular risk

Patients with chronic kidney disease (CKD) are at an increased cardiovascular risk compared with the general population, which is driven, at least in part, by mechanisms that are uniquely associated with kidney disease. In CKD, increased levels of oxidative stress and uraemic retention solutes, including urea and advanced glycation end products, enhance non-enzymatic post-translational modification events, such as protein oxidation, glycation, carbamylation and guanidinylation. Alterations in enzymatic post-translational modifications such as glycosylation, ubiquitination, acetylation and methylation are also detected in CKD. Post-translational modifications can alter the structure and function of proteins and lipoprotein particles, thereby affecting cellular processes. In CKD, evidence suggests that post-translationally modified proteins can contribute to inflammation, oxidative stress and fibrosis, and induce vascular damage or prothrombotic effects, which might contribute to CKD progression and/or increase cardiovascular risk in patients with CKD. Consequently, post-translational protein modifications prevalent in CKD might be useful as diagnostic biomarkers and indicators of disease activity that could be used to guide and evaluate therapeutic interventions, in addition to providing potential novel therapeutic targets.

Characteristics of calcified nodule attributable to culprit lesion in acute coronary syndrome: A systematic review and meta-analysis

The presence of calcified nodule (CN) is a significant characteristic of atherothrombosis in acute coronary syndrome (ACS). However, its characteristics continue to be understudied. This review aimed to further investigate these characteristics. This study found that CN was a distinctive feature of an atheromatous plaque, representing 6.3% of ACS. CN was more common in NSTE-ACS than in STEMI patients (9.4% vs. 6.6%). CN was also chiefly observed in the left anterior descendant artery (48%), followed by the right coronary (40.4%) and left circumflex (14.5%) arteries. Higher prevalence of hypertension (78.8%), diabetes mellitus (50.8%), multivessel disease (71.7%), and kidney disease (26.43%) were noted in CN compared to non-CN patients. CN-associated ACS also 6-fold increased the risk of target lesion revascularization compared to those without CN.

FOXO1 regulates RUNX2 ubiquitination through SMURF2 in calcific aortic valve disease

The prevalence of calcific aortic valve disease (CAVD) remains substantial while there is currently no medical therapy available. Forkhead box O1 (FOXO1) is known to be involved in the pathogenesis of cardiovascular diseases, including vascular calcification and atherosclerosis; however, its specific role in calcific aortic valve disease remains to be elucidated. In this study, we identified FOXO1 significantly down-regulated in the aortic valve interstitial cells (VICs) of calcified aortic valves by investigating clinical specimens and GEO database analysis. FOXO1 silencing or inhibition promoted VICs osteogenic differentiation in vitro and aortic valve calcification in Apoe-/- mice, respectively. We identified that FOXO1 facilitated the ubiquitination and degradation of RUNX2, which process was mainly mediated by SMAD-specific E3 ubiquitin ligase 2 (SMURF2). Our discoveries unveil a heretofore unacknowledged mechanism involving the FOXO1/SMURF2/RUNX2 axis in CAVD, thereby proposing the potential therapeutic utility of FOXO1 or SMURF2 as viable strategies to impede the progression of CAVD.

Development and evaluation of a chronic kidney disease risk prediction model using random forest

This research aims to advance the detection of Chronic Kidney Disease (CKD) through a novel gene-based predictive model, leveraging recent breakthroughs in gene sequencing. We sourced and merged gene expression profiles of CKD-affected renal tissues from the Gene Expression Omnibus (GEO) database, classifying them into two sets for training and validation in a 7:3 ratio. The training set included 141 CKD and 33 non-CKD specimens, while the validation set had 60 and 14, respectively. The disease risk prediction model was constructed using the training dataset, while the validation dataset confirmed the model's identification capabilities. The development of our predictive model began with evaluating differentially expressed genes (DEGs) between the two groups. We isolated six genes using Lasso and random forest (RF) methods-DUSP1, GADD45B, IFI44L, IFI30, ATF3, and LYZ-which are critical in differentiating CKD from non-CKD tissues. We refined our random forest (RF) model through 10-fold cross-validation, repeated five times, to optimize the mtry parameter. The performance of our model was robust, with an average AUC of 0.979 across the folds, translating to a 91.18% accuracy. Validation tests further confirmed its efficacy, with a 94.59% accuracy and an AUC of 0.990. External validation using dataset GSE180394 yielded an AUC of 0.913, 89.83% accuracy, and a sensitivity rate of 0.889, underscoring the model's reliability. In summary, the study identified critical genetic biomarkers and successfully developed a novel disease risk prediction model for CKD. This model can serve as a valuable tool for CKD disease risk assessment and contribute significantly to CKD identification.

Coronary Artery Disease in Patients Undergoing Hemodialysis: A Problem that Sounds the Alarm

Chronic kidney disease (CKD) is affecting more and more individuals over time. The importance of the increased prevalence is enhanced by the close association with the increased risk of poor individual outcomes such as death, fatal and non-fatal cardiovascular (CV) events and progression to end stage kidney disease (ESKD). ESKD requires replacement treatment such as hemodialysis (HD), a particular and complex context that unfortunately has been rarely considered in observational studies in the last few decades. The current perspective of HD as a bridge to kidney transplant requires greater attention from observational and experimental research both in the prevention and treatment of CV events in ESKD patients. We present a narrative review by performing a literature review to extrapolate the most significant articles exploring the CV risk, in particular coronary artery disease (CAD), in ESKD and evaluating possible innovative diagnostic and therapeutic tools in these patients. The risk of CAD increases linearly when the estimated glomerular filtration rate (eGFR) declines and reached the most significant level in ESKD patients. Several diagnostic techniques have been evaluated to predict CAD in ESKD such as laboratory tests (Troponin-T, N-terminal pro b-type natriuretic peptide, alkaline phosphatase), echocardiography and imaging techniques for vascular calcifications evaluation. Similarly, treatment is based on lifestyle changes, medical therapy and invasive techniques such as coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI). Unfortunately in the literature there are no clear indications of the usefulness and validity of biomarkers and possible treatments in ESKD patients. Considering the ESKD weight in terms of prevalence and costs it is necessary to implement clinical research in order to develop prognostic reliable biomarkers for CV and CAD risk prediction, in patients with ESKD. It should be highlighted that HD is a peculiar setting that offers the opportunity to implement research and facilitates patient monitoring by favoring the design of clinical trials.

Multi-Omic Analysis Reveals Genetic Determinants and Therapeutic Targets of Chronic Kidney Disease and Kidney Function

Chronic kidney disease (CKD) presents a significant global health challenge, characterized by complex pathophysiology. This study utilized a multi-omic approach, integrating genomic data from the CKDGen consortium alongside transcriptomic, metabolomic, and proteomic data to elucidate the genetic underpinnings and identify therapeutic targets for CKD and kidney function. We employed a range of analytical methods including cross-tissue transcriptome-wide association studies (TWASs), Mendelian randomization (MR), summary-based MR (SMR), and molecular docking. These analyses collectively identified 146 cross-tissue genetic associations with CKD and kidney function. Key Golgi apparatus-related genes (GARGs) and 41 potential drug targets were highlighted, with MAP3K11 emerging as a significant gene from the TWAS and MR data, underscoring its potential as a therapeutic target. Capsaicin displayed promising drug-target interactions in molecular docking analyses. Additionally, metabolome- and proteome-wide MR (PWMR) analyses revealed 33 unique metabolites and critical inflammatory proteins such as FGF5 that are significantly linked to and colocalized with CKD and kidney function. These insights deepen our understanding of CKD pathogenesis and highlight novel targets for treatment and prevention.

Management Considerations for Acute Coronary Syndromes in Chronic Kidney Disease

PURPOSE OF REVIEW

Propensity of patients with chronic kidney disease (CKD) to adverse outcomes of acute coronary syndromes (ACS) derives, in part, from imperfection in management. Dearth of data resulting from underrepresentation of patients with CKD in ACS trials and underuse of evidence-based testing and therapy compound biological risks inherent to CKD. We sought in this narrative review to critically appraise contemporary evidence and offer suggested approaches to practicing clinicians for the optimization of ACS management in patients with CKD.

RECENT FINDINGS

Updated multisociety chest pain guidelines emphasize the diversity of clinical presentations of ACS, pertinent to recognition of ACS in patients with CKD. Evolving tools to predict and prevent acute kidney injury complicating invasive management of ACS serve to support improved access to and safety of percutaneous coronary intervention (PCI) in CKD patients, who remain at elevated risk. Growth in use of radial access, advances in PCI quality, incorporation of intravascular imaging, and new options and insights in pharmacotherapy contribute to an evolving calculus of ischemic and bleeding risk in ACS with bearing on management in CKD patients. Key opportunities to improve outcomes of ACS for patients with CKD center on avoiding underuse of beneficial medical and invasive therapies; enhancing safety of therapies by leveraging evidence-based strategies to prevent acute kidney injury; and devoting specific effort to investigation of ACS management in the context of CKD.

[Arterial mediacalcinosis in patients with diabetes mellitus: etiopathogenetic and histopathological aspects]

In a review of the generalized results of foreign and domestic studies on the development mechanism and pathogenesis of vascular calcification. The etiopathogenetic, pathophysiological and histomorphological features of mediacalcinosis, which reveal changes in the vascular bed in patients with DM, are considered. The role of risk factors for diseases, such as increased glycemia, changes in insulin levels, impaired lipid metabolism, obesity, arterial hypertension, CKD and aging, is indicated. The role of procalcifying and anticalcifying factors in colonic vascular remodeling is discussed. Identification of informative molecular markers and factors of CS will allow in the future to develop effective strategies for drug management of the risk of their progression and individual prevention programs to improve the quality and life expectancy in patients with cardiovascular diseases.

Vascular Calcification Heterogeneity from Bench to Bedside: Implications for Manifestations, Pathogenesis, and Treatment Considerations

Vascular calcification (VC) is the ectopic deposition of calcium-containing apatite within vascular walls, exhibiting a high prevalence in older adults, and those with diabetes or chronic kidney disease. VC is a subclinical cardiovascular risk trait that increases mortality and functional deterioration. However, effective treatments for VC remain largely unavailable despite multiple attempts. Part of this therapeutic nihilism results from the failure to appreciate the diversity of VC as a pathological complex, with unforeseeable variations in morphology, risk associates, and anatomical and molecular pathogenesis, affecting clinical management strategies. VC should not be considered a homogeneous pathology because accumulating evidence refutes its conceptual and content uniformity. Here, we summarize the pathophysiological sources of VC heterogeneity from the intersecting pathways and networks of cellular, subcellular, and molecular crosstalk. Part of these pathological connections are synergistic or mutually antagonistic. We then introduce clinical implications related to the VC heterogeneity concept. Even within the same individual, a specific artery may exhibit the strongest tendency for calcification compared with other arteries. The prognostic value of VC may only be detectable with a detailed characterization of calcification morphology and features. VC heterogeneity is also evident, as VC risk factors vary between different arterial segments and layers. Therefore, diagnostic and screening strategies for VC may be improved based on VC heterogeneity, including the use of radiomics. Finally, pursuing a homogeneous treatment strategy is discouraged and we suggest a more rational approach by diversifying the treatment spectrum. This may greatly benefit subsequent efforts to identify effective VC therapeutics.

Increased cardiovascular risk in patients with chronic kidney disease

Cardiovascular disease (CVD) is highly prevalent in patients suffering from chronic kidney disease (CKD). The risk of patients with CKD developing CVD is manifested already in the early stages of CKD development. The impact of declined kidney function on increased cardiovascular risk and the underlying mechanisms are complex and multifactorial. This review discusses the impact of (a) traditional cardiovascular risk factors such as smoking, dyslipidemia, diabetes, and hypertension as well as (b) CKD-specific pathophysiological and molecular mechanisms associated with an increased cardiovascular risk. The latter include uremic toxins, post-translational modifications and uremic lipids, innate immune cell activation and inflammation, oxidative stress, endothelial cell dysfunction, increased coagulation and altered platelet responses, vascular calcification, renin-angiotensin-aldosterone-system (RAAS) and sympathetic activation, as well as anemia. Unraveling the complex interplay of different risk factors, especially in the context of patient subcohorts, will help to find new therapeutic approaches in order to reduce the increased cardiovascular risk in this vulnerable patient cohort.

Phosphate in Cardiovascular Disease: From New Insights Into Molecular Mechanisms to Clinical Implications

Hyperphosphatemia is a common feature in patients with impaired kidney function and is associated with increased risk of cardiovascular disease. This phenomenon extends to the general population, whereby elevations of serum phosphate within the normal range increase risk; however, the mechanism by which this occurs is multifaceted, and many aspects are poorly understood. Less than 1% of total body phosphate is found in the circulation and extracellular space, and its regulation involves multiple organ cross talk and hormones to coordinate absorption from the small intestine and excretion by the kidneys. For phosphate to be regulated, it must be sensed. While mostly enigmatic, various phosphate sensors have been elucidated in recent years. Phosphate in the circulation can be buffered, either through regulated exchange between extracellular and cellular spaces or through chelation by circulating proteins (ie, fetuin-A) to form calciprotein particles, which in themselves serve a function for bulk mineral transport and signaling. Either through direct signaling or through mediators like hormones, calciprotein particles, or calcifying extracellular vesicles, phosphate can induce various cardiovascular disease pathologies: most notably, ectopic cardiovascular calcification but also left ventricular hypertrophy, as well as bone and kidney diseases, which then propagate phosphate dysregulation further. Therapies targeting phosphate have mostly focused on intestinal binding, of which appreciation and understanding of paracellular transport has greatly advanced the field. However, pharmacotherapies that target cardiovascular consequences of phosphate directly, such as vascular calcification, are still an area of great unmet medical need.

Intracellular proteomics and extracellular vesiculomics as a metric of disease recapitulation in 3D-bioprinted aortic valve arrays

In calcific aortic valve disease (CAVD), mechanosensitive valvular cells respond to fibrosis- and calcification-induced tissue stiffening, further driving pathophysiology. No pharmacotherapeutics are available to treat CAVD because of the paucity of (i) appropriate experimental models that recapitulate this complex environment and (ii) benchmarking novel engineered aortic valve (AV)-model performance. We established a biomaterial-based CAVD model mimicking the biomechanics of the human AV disease-prone fibrosa layer, three-dimensional (3D)-bioprinted into 96-well arrays. Liquid chromatography-tandem mass spectrometry analyses probed the cellular proteome and vesiculome to compare the 3D-bioprinted model versus traditional 2D monoculture, against human CAVD tissue. The 3D-bioprinted model highly recapitulated the CAVD cellular proteome (94% versus 70% of 2D proteins). Integration of cellular and vesicular datasets identified known and unknown proteins ubiquitous to AV calcification. This study explores how 2D versus 3D-bioengineered systems recapitulate unique aspects of human disease, positions multiomics as a technique for the evaluation of high throughput-based bioengineered model systems, and potentiates future drug discovery.

Cardiovascular Consequences of Uremic Metabolites: an Overview of the Involved Signaling Pathways

The crosstalk of the heart with distant organs such as the lung, liver, gut, and kidney has been intensively approached lately. The kidney is involved in (1) the production of systemic relevant products, such as renin, as part of the most essential vasoregulatory system of the human body, and (2) in the clearance of metabolites with systemic and organ effects. Metabolic residue accumulation during kidney dysfunction is known to determine cardiovascular pathologies such as endothelial activation/dysfunction, atherosclerosis, cardiomyocyte apoptosis, cardiac fibrosis, and vascular and valvular calcification, leading to hypertension, arrhythmias, myocardial infarction, and cardiomyopathies. However, this review offers an overview of the uremic metabolites and details their signaling pathways involved in cardiorenal syndrome and the development of heart failure. A holistic view of the metabolites, but more importantly, an exhaustive crosstalk of their known signaling pathways, is important for depicting new therapeutic strategies in the cardiovascular field.

Food to Prevent Vascular Calcification in Chronic Kidney Disease

Vascular calcification (VC) is a consequence of chronic kidney disease (CKD) which is of paramount importance regarding the survival of CKD patients. VC is far from being controlled with actual medication; as a result, in recent years, diet modulation has become more compelling. The concept of medical nutritional therapy points out the idea that food may prevent or treat diseases. The aim of this review was to evaluate the influence of food habits and nutritional intervention in the occurrence and progression of VC in CKD. Evidence reports the harmfulness of ultra-processed food, food additives, and animal-based proteins due to the increased intake of high absorbable phosphorus, the scarcity of fibers, and the increased production of uremic toxins. Available data are more supportive of a plant-dominant diet, especially for the impact on gut microbiota composition, which varies significantly depending on VC presence. Magnesium has been shown to prevent VC but only in experimental and small clinical studies. Vitamin K has drawn considerable attention due to its activation of VC inhibitors. There are positive studies; unfortunately, recent trials failed to prove its efficacy in preventing VC. Future research is needed and should aim to transform food into a medical intervention to eliminate VC danger in CKD.

Variability in structure, morphology, and mechanical properties of the descending thoracic and infrarenal aorta around their circumference

Aortic diseases, such as aneurysms, atherosclerosis, and dissections, demonstrate a preferential development and progression around the aortic circumference, resulting in a highly heterogeneous disease state around the circumference. Differences in the aorta's structural composition and mechanical properties may be partly responsible for this phenomenon. Our goal in this study was to analyze the mechanical and structural properties of the human aorta at its lateral, anterior, posterior, and medial quadrants in two regions prone to circumferentially inhomogeneous diseases, descending Thoracic Aorta (TA) and Infrarenal Aorta (IFR). Human aortas were obtained from 10 donors (64 ± 11 years) and dissected from their loose surrounding tissue. Mechanical properties were determined in all four quadrants of TA and IFR using planar biaxial testing and fitted to three common constitutive models. The structure of tissues was assessed using Movat Pentachrome stained histology slides. We observed that the anterior quadrant exhibited the greatest thickness, followed by the lateral region, in both the TA and IFR. In TA, the posterior wall appeared as the stiffest location in most samples, while in IFR, the anterior wall was the stiffest. We observed a higher glycosaminoglycans content in the lateral and posterior regions of the IFR. We found elastin density to be similar in TA lateral, anterior, and posterior quadrants, while in IFR, the anterior region demonstrated the highest elastin density. Despite significant variations between subjects, this study highlights the distinct morphometrical, mechanical, and structural properties between the quadrants of both TA and IFR.

Secondary Hyperparathyroidism

Secondary hyperparathyroidism (SHPT) does not initiate as a primary dysfunction of parathyroid glands resulting from an intrinsic defect or disease but is the physiologic response of parathyroids to metabolic changes elsewhere in the body occurring over time. SHPT is a manifestation of a chronic condition that classically occurs from chronic kidney disease. In fact, given the relatively recent transition of populations from outside (agrarian) to indoor (industrial, information technology, and so forth) employment and a consequent reduction in sun exposure, combined with diets of highly processed food, vitamin D and calcium deficiencies are now the leading causes of SHPT.

Spice Up Your Kidney: A Review on the Effects of Capsaicin in Renal Physiology and Disease

Capsaicin, the organic compound which attributes the spicy flavor and taste of red peppers and chili peppers, has been extensively studied for centuries as a potential natural remedy for the treatment of several illnesses. Indeed, this compound exerts well-known systemic pleiotropic effects and may thus bring important benefits against various pathological conditions like neuropathic pain, rhinitis, itching, or chronic inflammation. Yet, little is known about the possible biological activity of capsaicin at the kidney level, as this aspect has only been addressed by sparse experimental investigations. In this paper, we aimed to review the available evidence focusing specifically on the effects of capsaicin on renal physiology, as well as its potential benefits for the treatment of various kidney disorders. Capsaicin may indeed modulate various aspects of renal function and renal nervous activity. On the other hand, the observed experimental benefits in preventing acute kidney injury, slowing down the progression of diabetic and chronic kidney disease, ameliorating hypertension, and even delaying renal cancer growth may set the stage for future human trials of capsaicin administration as an adjuvant or preventive therapy for different, difficult-to-treat renal diseases.

Medical Management of Coronary Artery Disease in Patients with Chronic Kidney Disease

Chronic kidney disease patients are at increased risk of cardiovascular disease, which is the leading cause of mortality among this population. In addition, chronic kidney disease is a major risk factor for the development of coronary artery disease and is widely regarded as a coronary artery disease risk equivalent. Medical therapy is the cornerstone of coronary artery disease management in the general population. However, there are few trials to guide medical therapy of coronary artery disease in chronic kidney disease, with most data extrapolated from clinical trials of mainly non-chronic kidney disease patients, which were not adequately powered to evaluate this subgroup. There is some evidence to suggest that the efficacy of certain therapies such as aspirin and statins is attenuated with declining estimated glomerular filtration rate, with questionable benefit among end-stage renal disease (ESRD) patients. Furthermore, chronic kidney disease and ESRD patients are at higher risk of potential side effects with therapy, which may limit their use. In this review, we summarize the available evidence supporting the safety and efficacy of medical therapy of coronary artery disease in chronic kidney disease and ESRD patients. We also discuss the data on new emerging therapies, including PCSK9i, SGLT2i, GLP1 receptor agonists, and nonsteroidal mineralocorticoid receptor antagonists, which show promise at reducing risk of cardiovascular events in the chronic kidney disease population and may offer additional treatment options. Overall, dedicated studies directly evaluating chronic kidney disease patients, particularly those with advanced chronic kidney disease and ESRD, are greatly needed to establish the optimal medical therapy for coronary artery disease and improve outcomes in this vulnerable population.

Association of dietary live microbe intake with abdominal aortic calcification in US adults: a cross-sectional study of NHANES 2013-2014

OBJECT

To explore the potential association between dietary live microbe intake and abdominal aortic calcification (AAC).

METHODS

We conducted a cross-section study based on the National Health and Nutrition Examination Survey (NHANES). We categorized the participants into three groups (low, medium, and high dietary intake of live microbes) according to Sanders's dietary live microbe classification system and participants' 24-h dietary recall data. AAC was quantified by using dual-energy X-ray absorptiometry (DXA) and diagnosed by using the Kauppila AAC-24 score system. The analyses utilized weighted logistic regression and weighted linear regression.

RESULTS

A total of 2,586 participants were included. After the full adjustment for covariates, compared to participants with a low dietary live microbe intake, participants with a high dietary live microbe intake had a significantly lower risk of severe AAC (OR: 0.39, 95% CI: 0.22, 0.68, p = 0.003), and the AAC score was also significantly decreased (β:-0.53, 95% CI: -0.83, -0.23, p = 0.002).

CONCLUSION

In this study, more dietary live microbial intake was associated with lower AAC scores and a lower risk of severe AAC. However, more research is needed to verify this.

Influence of sodium thiosulfate on coronary artery calcification of patients on dialysis: a meta-analysis

Coronary artery calcification (CAC) is common in dialysis patients and is associated with a higher risk of future cardiovascular events. Sodium thiosulfate (STS) is effective for calciphylaxis in dialysis patients; however, the influence of STS on CAC in dialysis patients remains unclear. This systematic review and meta-analysis were conducted to evaluate the effects of STS on CAC in patients undergoing dialysis. PubMed, Embase, Cochrane Library, CNKI, and Wanfang databases were searched from inception to 22 March 2023 for controlled studies comparing the influence of STS versus usual care without STS on CAC scores in dialysis patients. A random effects model incorporating the potential influence of heterogeneity was used to pool the results. Nine studies, including two non-randomized studies and seven randomized controlled trials, were included in the meta-analysis. Among these, 365 patients on dialysis were included in the study. Compared with usual care without STS, intravenous STS for 3-6 months was associated with significantly reduced CAC scores (mean difference [MD] = -180.17, 95% confidence interval [CI]: -276.64 to -83.70, p < 0.001, I2 = 0%). Sensitivity analysis limited to studies of patients on hemodialysis showed similar results (MD: -167.33, 95% CI: -266.57 to -68.09, p = 0.001; I2 = 0%). Subgroup analyses according to study design, sample size, mean age, sex, dialysis vintage of the patients, and treatment duration of STS also showed consistent results (p for subgroup differences all > 0.05). In conclusion, intravenous STS may be effective in attenuating CAC in dialysis patients.

Future treatment of vascular calcification in chronic kidney disease

INTRODUCTION

Cardiovascular disease (CVD) is one of the global leading causes of morbidity and mortality in chronic kidney disease (CKD) patients. Vascular calcification (VC) is a major cause of CVD in this population and is the consequence of complex interactions between inhibitor and promoter factors leading to pathological deposition of calcium and phosphate in soft tissues. Different pathological landscapes are associated with the development of VC, such as endothelial dysfunction, oxidative stress, chronic inflammation, loss of mineralization inhibitors, release of calcifying extracellular vesicles (cEVs) and circulating calcifying cells.

AREAS COVERED

In this review, we examined the literature and summarized the pathophysiology, biomarkers and focused on the treatments of VC.

EXPERT OPINION

Even though there is no consensus regarding specific treatment options, we provide the currently available treatment strategies that focus on phosphate balance, correction of vitamin D and vitamin K deficiencies, avoidance of both extremes of bone turnover, normalizing calcium levels and reduction of inflammatory response and the potential and promising therapeutic approaches liketargeting cellular mechanisms of calcification (e.g. SNF472, TNAP inhibitors).Creating novel scores to detect in advance VC and implementing targeted therapies is crucial to treat them and improve the future management of these patients.