Vascular Calcification in Chronic Kidney Disease: Diversity in the Vessel Wall

Efficacy and safety of tenapanor vs placebo in treating CKD patients on dialysis and with hyperphosphatemia: a systematic review and meta-analysis of 2251 patients

BACKGROUND

Hyperphosphatemia is common in chronic kidney disease (CKD) patients, especially patients on hemodialysis. Tenapanor is a novel drug with fewer side effects and high compliance compared to traditional phosphate binders. We conducted a systematic review and meta-analysis to evaluate the efficacy and safety of tenapanor.

METHODS

A comprehensive search was conducted on PubMed, Scopus, Web of Science, and Cochrane Library, from inception to June 25, 2024. Nine randomized controlled trials (RCTs) and three single-arm studies comparing tenapanor to placebo were included. By adopting a random-effect empirical Bayes model, STATA and RevMan were used to pool dichotomous and continuous data. The primary outcome assessed was serum phosphate. Secondary outcomes included intact parathyroid hormone (iPTH), serum calcium, potassium, and sodium, bowel movement frequency, stool consistency using BSFS score and safety outcomes.

RESULTS

Twelve studies with a total of 2,251 patients were included. Tenapanor was superior to placebo in reducing phosphate at all assessed end points, week 1 (MD = -1.28 mg/dL, P < 0.001), week 2 (MD = -1.07 mg/dL, P < 0.001), week 3 (MD = -1.22 mg/dL, P < 0.001), and week 4 (MD = -0.91 mg/dL, P < 0.001). In addition, iPTH was almost statistically significantly lower in the tenapanor group (MD = -36.53 ng/L, P = 0.07). Moreover, it led to a statistically significant reduction in sodium level (MD = -0.7 mmol/L, P = 0.0003). On the contrary, tenapanor had no statistically significant effect on calcium or potassium levels. Bowel movement frequency and stool consistency were significantly higher in the tenapanor group at all assessed end points. Regarding safety analysis, diarrhea and nausea were statistically significantly higher in the tenapanor group, (RR = 3.71, P < 0.001) and (RR = 1.97, P < 0.001), respectively. There were no significant differences in other adverse events.

CONCLUSION

Based on our meta-analysis, tenapanor can effectively reduce serum phosphate, iPTH, and sodium. Additionally, it improves bowel movement frequency and stool consistency. However, it is associated with a higher risk of GIT symptoms that should be considered and managed during treatment. We recommend conducting further RCTs to perform head-to-head comparisons against other active comparators such as phosphate binders.

Serum midkine level and its association with subclinical coronary artery calcification and carotid atherosclerosis in chronic kidney disease

BACKGROUND

There are no studies investigating the role of midkine (MK) in vascular calcification (VC) or vascular disease associated with chronic kidney disease (CKD). This study assessed serum MK level and investigated its relationship with carotid atherosclerosis and coronary artery calcification (CAC) in non-dialysis CKD.

METHODS

The study comprised 80 controls and 185 adult patients with CKD at stages 3-5 who were free of cardiovascular diseases. Acute renal failure, chronic hemodialysis, severe liver disease, inflammatory states, anticoagulation therapy and cancer were excluded. The patients were classified based on presence of CAC score into severe and mild to moderate CAC groups. They were also divided into atherosclerotic and non-atherosclerotic groups based on carotid atherosclerosis. CBC, kidney function tests, lipid profile, intact parathyroid hormone (iPTH), and phosphorus were assessed. Serum levels of MK, tumor necrosis factor- α (TNF- α), interleukin-6 (IL-6), and high-sensitivity C-reactive protein (hs-CRP) were quantitatively tested using ELISA. Cardiac CT scan was done to calculate CAC score. Carotid ultrasonography was used to evaluate carotid intima media thickness (CIMT) and identify plaques.

RESULTS

All CKD categories, including CKD-3, CKD-4, and CKD-5, showed higher rates of carotid plaques (p = 0.007, p < 0.001, and p < 0.001, respectively), higher levels of MK (p < 0.001 for each), and higher CAC scores (p < 0.001 for each) as CKD worsened. Compared to mild to moderate CAC patients, severe CAC patients showed increased CIMT (p < 0.001) and raised serum levels of MK (p < 0.001), TNF-α (p = 0.001), IL-6 (p = 0.002), hs-CRP (p = 0.003), iPTH (p = 0.02), phosphorus (p < 0.001), total cholesterol (TC), and low density lipoprotein-cholesterol (LDL-C). Multivariate linear regression revealed that CAC was reliably predicted by MK (p = 0.008) and serum creatinine (p = 0.001). Carotid atherosclerotic patients had higher serum levels of MK, TNF-α, IL-6, hs-CRP, iPTH, phosphorus, TC, total triglycerides and LDL-C (p < 0.001 for each). Multivariate logistic regression showed that serum MK (p = 0.001), serum creatinine (p = 0.005), age (p < 0.001), iPTH (p = 0.007), and IL-6 (p = 0.024) were significant predictors of carotid atherosclerosis.

CONCLUSIONS

As CKD worsened, MK levels, carotid atherosclerosis and CAC increased. Serum MK was a reliable biomarker for asymptomatic carotid atherosclerosis and CAC in non-dialysis CKD, allowing prompt early diagnosis to avert cardiovascular morbidity and death in the future.

TRIAL REGISTRATION

The trial number was 1138 and its registration was approved by the hospital's Research Ethics Committee in 4/2024.

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.

Simulating Arterial Stress for Rapid Evaluation of Antivascular Calcification Therapies from Herbal Extracts

Vascular calcification severely disrupts cardiovascular hemodynamics, leading to high rates of morbidity and mortality. Despite their clinical impact, the development of effective treatments remains limited, underscoring an urgent need for efficient and reliable drug screening methods. Vascular smooth muscle cells (VSMCs) are known to play a central role in driving the calcification process, undergoing an osteogenic transition in response to pathological conditions. To mimic this process, we developed a cyclic stretching device that replicates the physiological mechanical stresses experienced by VSMCs during arterial pulsation. This device dramatically accelerates the osteogenic transition of VSMCs, reducing phenotypic switching from 13 days under static conditions to just 4 h. Using this device, we screened 20 herbal extracts for anticalcification properties and identifiedSalvia miltiorrhizaas a candidate with therapeutic potential that inhibits VSMC osteogenic transdifferentiation in vitro. The anticalcification efficacy ofSalvia miltiorrhizawas further validated in a vitamin D-induced rat model of cardiovascular calcification, highlighting its translational potential. This screening platform provides a rapid and physiologically relevant method for evaluating potential antivascular calcification therapies, significantly improving the efficiency of drug discovery for clinical translation.

Nutrition support for patients with renal dysfunction in the intensive care unit: A narrative review

Providing optimal nutrition support in the intensive care unit (ICU) is a challenging and dynamic process. Energy, protein, fluid, electrolyte, and micronutrient requirements all can be altered in patients with acute, chronic, and acute-on-chronic kidney disease. Given that renal dysfunction occurs in up to one-half of ICU patients, it is imperative that nutrition support providers understand how renal dysfunction, its metabolic consequences, and its treatments, including renal replacement therapy (RRT), affect patients' nutrition needs. Data on nutrient requirements in critically ill patients with renal dysfunction are sparse. This article provides an overview of renal dysfunction in the ICU and identifies and addresses the unique nutrition challenges present among these patients, including those receiving RRT, as supported by the available literature and guidelines.

Qianyang Yuyin granules alleviate hypertension-induced vascular remodeling by inhibiting the phenotypic switch of vascular smooth muscle cells

ETHNOPHARMACOLOGICAL RELEVANCE

Qianyang Yuyin granules (QYYY) have been used clinically to treat hypertension for over two decades. Previous clinical trials have shown that QYYY can improve vascular elastic function in hypertensive patients. However, the underlying pharmacological mechanism is unclear.

AIM OF THE STUDY

To elucidate the effects and mechanisms of QYYY on vascular remodeling using a multidisciplinary approach that includes network pharmacology, proteomics, and both in vitro and in vivo experiments.

MATERIALS AND METHODS

The main components of QYYY were identified using ultra-high-performance liquid chromatography and high-resolution mass spectrometry. Network pharmacology and molecular docking were employed to predict QYYY's primary active ingredients, potential therapeutic targets and intervention pathways in hypertensive vascular remodeling. We induced hypertension in male C57BL/6 mice by infusing angiotensin II (Ang II) via osmotic minipumps, and performed pre-treatment with QYYY or Sacubitril/valsartan (Entresto). Blood pressure was monitored in vivo, followed by the extraction of aortas to examine pathological structural changes and alterations in protein expression patterns. The expression and location of proteins involved in the HIF-1α/TWIST1/P-p65 signaling pathway were investigated, as well as markers of vascular smooth muscle cells (VSMCs) phenotypic switch. In vitro, we studied the effects of QYYY water extract on Ang II-stimulated human aortic VSMCs. We investigated whether QYYY could affect the HIF-1α/TWIST1/P-p65 signaling pathway, thereby ameliorating apoptosis, autophagy, and phenotype switch in VSMCs.

RESULTS

We identified 62 main compounds in QYYY, combined with network pharmacology, speculated 827 potentially active substances, and explored 1021 therapeutic targets. The KEGG pathway analysis revealed that the mechanisms of action associated with QYYY therapy potentially encompass various biological processes, including metabolic pathways, TNF signaling pathways, apoptosis, Ras signaling pathways, HIF-1 signaling pathways, autophagy-animal pathways. In hypertensive mice, QYYY restored abnormally elevated blood pressure, vascular remodeling, and inflammation with a dose-response relationship while altering abnormal protein patterns. In vitro, QYYY could inhibit abnormal proliferation, migration, intracellular Ca2+ accumulation and cytoskeletal changes of VSMCs. It improved mitochondrial function, reduced ROS levels, stabilized membrane potential, prevented cell death, and reduced overproduction of TGF-β1, TNF-a, and IL-1β.

CONCLUSION

QYYY may be able to inhibit the overactivation of the HIF-1α/TWIST1/P-p65 signaling pathway, improve the phenotypic switch, and balance apoptosis and autophagy in VSMCs, thereby effectively improving vascular remodeling caused by hypertension.

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.

Prevalence of Vitamin K2 Deficiency and Its Association with Coronary Artery Disease: A Case-Control Study

BACKGROUND/OBJECTIVES

Vitamin K2 analogs are associated with decreased vascular calcification, which may provide protective benefits for individuals with coronary artery disease (CAD) by stimulating anti-calcific proteins like matrix Gla protein and adjusting innate immune responses. This study addresses a significant gap in understanding the association between serum levels of vitamin K2 analogs in different CAD types and examines their correlations with clinical risk parameters in CAD patients.

METHODS

This case-control study enrolled CAD patients and healthy controls to assess and compare serum concentrations of two vitamin K2 analogs including menaquinone-4 (MK-4) and menaquinone-7 (MK-7) via ultra-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS). CAD risk factors were evaluated and related to serum levels of vitamin K2 analogs. The CAD group was further subdivided into stable angina, STEMI, NSTEMI, and unstable angina groups to investigate potential differences in vitamin K2 analog levels.

RESULTS

Patients experiencing acute coronary syndrome exhibited notably reduced serum levels of MK-4 and MK-7 (1.61 ± 0.66, and 1.64 ± 0.59 ng/mL, respectively) in comparison to the control group (2.29 ± 0.54, and 2.16 ± 0.46 ng/mL, respectively), with MK-4 and MK-7 displaying stronger associations with CAD risk indicators. Notable variations in vitamin K2 analog levels were found between CAD patients and control groups (p < 0.001). Unstable angina patients showed the lowest serum levels of MK-4 and MK-7.

CONCLUSIONS

The present study demonstrated a higher prevalence rate of vitamin K2 deficiency among patients with CAD. The most pronounced decrease in MK-4 and MK-7 was observed in unstable angina patients. Moreover, these outcomes indicate the imperative requirement for an integrative approach that incorporates metabolic, lipid, and vitamin K2-related pathways in the risk stratification and management of CAD.

Role of macrophages in vascular calcification: From the perspective of homeostasis

Vascular calcification (VC) is a crucial risk factor for the high morbidity and mortality associated with cardiovascular and cerebrovascular diseases. With the global population aging, the incidence of VC is escalating annually. However, due to its silent clinical process, VC often results in irreversible clinical outcomes. Inflammation is a core element in the VC process, and macrophages are the major inflammatory cells. Due to their diverse origins, microenvironments, and polarization states, macrophages exhibit significant heterogeneity, exerting strong effects on the occurrence, development, and even the regression of VC. In this review, we summarize the origin, distribution, classification, and surface markers of macrophages. Simultaneously, we explore the mechanisms by which macrophages maintain homeostasis or regulate inflammation, including the macrophage-mediated regulation of VC through the release of inflammatory factors, osteogenic genes, extracellular vesicles, and alterations in efferocytosis. Finally, we discuss research targeting inflammation and macrophages to develop novel therapeutic regimens for preventing and treating VC.

Impact of serum cholinesterase on calcified nodules in patients with stable coronary artery disease

BACKGROUND

Calcified nodules (CNs) are an advanced stage of coronary calcification that can have significant clinical implications. We investigated factors associated with CNs, the etiology of which is not fully understood.

METHODS

We retrospectively evaluated 619 patients with stable coronary artery disease who underwent intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI). CNs in the culprit lesion were evaluated via IVUS, and all-cause mortality and major cardiovascular and cerebrovascular events (MACCEs) were compared between the CN and non-CN groups.

RESULTS

The CN group ( n  = 40 patients) had a significantly lower survival rate and a higher incidence of MACCE than the non-CN group ( P  = 0.020 and P  < 0.001, respectively). Multivariate logistic regression analysis models revealed that chronic kidney disease and serum cholinesterase (ChE) level were associated with CN formation [odds ratio (OR): 3.15, 95% confidence interval (CI): 1.30-7.69, P  = 0.001 and OR: 0.94, 95% CI: 0.88-0.99, P  = 0.042]. The optimal cutoff of serum ChE level as per the receiver operating characteristic curve was 309 units/l (Area under the curve = 0.67, sensitivity = 93%, specificity = 40%, P  = 0.001). The low-ChE group divided according to the optimal cutoff value showed significantly higher cumulative incidence of MACCEs after PCI than the high-ChE group as per Kaplan-Meier analysis.

CONCLUSION

The presence of CNs is significantly associated with a poor prognosis and MACCE after PCI among patients with stable coronary artery disease. Serum ChE levels may affect CN formation.

Advances in the mechanisms of vascular calcification in chronic kidney disease

Vascular calcification (VC) is common in patients with advanced chronic kidney disease (CKD).A series of factors, such as calcium and phosphorus metabolism disorders, uremic toxin accumulation, inflammation and oxidative stress and cellular senescence, cause osteoblast-like differentiation of vascular smooth muscle cells, secretion of extracellular vesicles, and imbalance of calcium regulatory factors, which together promote the development of VC in CKD. Recent advances in epigenetics have provided better tools for the investigation of VC etiology and new approaches for finding more accurate biomarkers. These advances have not only deepened our understanding of the pathophysiological mechanisms of VC in CKD, but also provided valuable clues for the optimization of clinical predictors and the exploration of potential therapeutic targets. The aim of this article is to provide a comprehensive overview of the pathogenesis of CKD VC, especially the new advances made in recent years, including the various key factors mentioned above. Through the comprehensive analysis, we expect to provide a solid theoretical foundation and research direction for future studies targeting the specific mechanisms of CKD VC, the establishment of clinical predictive indicators and the development of potential therapeutic strategies.

The Physiological Functions and Therapeutic Potential of Hypoxia-Inducible Factor-1α in Vascular Calcification

HIF-1α plays a crucial regulatory role in vascular calcification (VC), primarily influencing the osteogenic differentiation of VSMCs through oxygen-sensing mechanisms. Under hypoxic conditions, the stability of HIF-1α increases, avoiding PHD and VHL protein-mediated degradation, which promotes its accumulation in cells and then activates gene expressions related to calcification. Additionally, HIF-1α modulates the metabolic state of VSMCs by regulating the pathways that govern the switch between glycolysis and oxidative phosphorylation, thereby further advancing the calcification process. The interaction between HIF-1α and other signaling pathways, such as nuclear factor-κB, Notch, and Wnt/β-catenin, creates a complex regulatory network that serves as a critical driving force in VC. Therefore, a deeper understanding of the role and regulatory mechanism of the HIF-1α signaling during the development and progression of VC is of great significance, as it is not only a key molecular marker for understanding the pathological mechanisms of VC but also represents a promising target for future anti-calcification therapies.

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.

Construction of a miR-15a-based risk prediction model for vascular calcification detection in patients undergoing hemodialysis

Vascular calcification (VC) is highly prevalent in patients undergoing hemodialysis, and is a significant contributor to the mortality rate. Therefore, biomarkers that can accurately predict the onset of VC are urgently required. Our study aimed to investigate serum miR-15a levels in relation to VC and to develop a predictive model for VC in patients undergoing hemodialysis at the Beijing Friendship Hospital hemodialysis center between 1 January 2019 and 31 December 2020. The patients were categorized into two groups: VC and non-VC. Logistic regression (LR) models were used to examine the risk factors associated with VC. Additionally, we developed an miR-15a-based nomogram based on the results of the multivariate LR analysis. A total of 138 patients under hemodialysis were investigated (age: 58.41 ± 13.22 years; 54 males). VC occurred in 79 (57.2%) patients. Multivariate LR analysis indicated that serum miR-15a, age, and WBC count were independent risk factors for VC. A miR-15a-based nomogram was developed by incorporating the following five predictors: age, dialysis vintage, predialysis nitrogen, WBC count, and miR-15a. The receiver operating characteristic (ROC) curve had an area under the curve of 0.921, diagnostic threshold of 0.396, sensitivity of 0.722, and specificity of 0.932, indicating that this model had good discrimination. This study concluded that serum miR-15a levels, age, and white blood cell (WBC) count are independent risk factors for VC. A nomogram constructed by integrating these risk factors can be used to predict the risk of VC in patients undergoing hemodialysis.

Systematic review and meta-analysis assessing the status of carotid intima-media thickness and lipid profiles in type 2 diabetes mellitus

OBJECTIVES

Carotid intima-media thickness (CIMT) is a measurement for subclinical atherosclerosis and has been associated with overall cardiovascular diseases, especially in type 2 diabetes mellitus (T2DM). We aimed to assess the status of carotid health and lipid profile in T2DM.

DESIGN

This systematic review and meta-analysis synthesised data published from clinical studies.

DATA SOURCES

Google Scholar, PubMed and Scopus were searched from inception to 18 January 2024.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies conducted in patients with T2DM and those without T2DM were included. Studies conducted in T2DM adults evaluating carotid status and lipid profile were considered.

DATA EXTRACTION AND SYNTHESIS

Two authors independently used standardised methods to comprehensively search, screen and extract data from all relevant studies. The risk of bias was assessed using the Newcastle-Ottawa checklist. Meta-analysis was conducted using Review Manager and metaHun through random effects models. The random effect model was used due to high heterogeneity.

RESULTS

Evidence was analysed from 57 studies with a sample size of 29 502 (8254 T2DM and 21 248 people without T2DM). There was a significantly higher CIMT, with a standardised mean difference (SMD) of 1.01 (95% CI 0.75, 1.26, p<0.00001). Additionally, there was an elevated triglyceride (TG) (SMD=1.12, 95% CI 0.82, 1.41, p<0.00001), total cholesterol (TC), (SMD=0.24, 95% CI 0.02, 0.46, p=0.03) and low-density lipoprotein-cholesterol (LDL-C), (SMD=0.35, 95% CI 0.11, 0.59, p=0.004) in patients with T2DM compared with those without T2DM. Furthermore, a significant decrease in high-density lipoprotein cholesterol (HDL-C) was observed in the T2DM compared with people without T2DM, SMD=-0.79, 95% CI -0.96, -0.62, p<0.00001). Age, body mass index and hypertension were associated with increased CIMT and TG and decreased HDL-C in T2DM. Additionally, age, gender and hypertension were associated with an increased LDL-C in T2DM.

CONCLUSION

Our findings suggest that an increased CIMT is accompanied by increased TG, TC, LDL-C and HDL-C reduction in patients with T2DM.

PROSPERO REGISTRATION NUMBER

CRD42023451731.

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.

Estimated glomerular filtration rate slope and risk of primary and secondary major adverse cardiovascular events and heart failure hospitalization in people with type 2 diabetes: An analysis of the EXSCEL trial

AIM

The decline in estimated glomerular filtration rate (eGFR), a significant predictor of cardiovascular disease (CVD), occurs heterogeneously in people with diabetes because of various risk factors. We investigated the role of eGFR decline in predicting CVD events in people with type 2 diabetes in both primary and secondary CVD prevention settings.

MATERIALS AND METHODS

Bayesian joint modelling of repeated measures of eGFR and time to CVD event was applied to the Exenatide Study of Cardiovascular Event Lowering (EXSCEL) trial to examine the association between the eGFR slope and the incidence of major adverse CV event/hospitalization for heart failure (MACE/hHF) (non-fatal myocardial infarction, non-fatal stroke, CV death, or hospitalization for heart failure). The analysis was adjusted for age, sex, smoking, systolic blood pressure, baseline eGFR, antihypertensive and lipid-lowering medication, diabetes duration, atrial fibrillation, high-density cholesterol, total cholesterol, HbA1c and treatment allocation (once-weekly exenatide or placebo).

RESULTS

Data from 11 101 trial participants with (n = 7942) and without (n = 3159) previous history of CVD were analysed. The mean ± SD eGFR slope per year in participants without and with previous CVD was -0.68 ± 1.67 and -1.03 ± 2.13 mL/min/1.73 m2, respectively. The 5-year MACE/hHF incidences were 7.5% (95% CI 6.2, 8.8) and 20% (95% CI 19, 22), respectively. The 1-SD decrease in the eGFR slope was associated with increased MACE/hHF risks of 48% (HR 1.48, 95% CI 1.12, 1.98, p = 0.007) and 33% (HR 1.33, 95% CI 1.18,1.51, p < 0.001) in participants without and with previous CVD, respectively.

CONCLUSIONS

eGFR trajectories over time significantly predict incident MACE/hHF events in people with type 2 diabetes with and without existing CVD, with a higher hazard ratio for MACE/hHF in the latter group.

Vitamin K for Vascular Calcification in Kidney Patients: Still Alive and Kicking, but Still a Lot to Learn

Patients with chronic kidney disease (CKD) suffer disproportionately from a high burden of cardiovascular disease, which, despite recent scientific advances, remains partly understood. Vascular calcification (VC) is the result of an ongoing process of misplaced calcium in the inner and medial layers of the arteries, which has emerged as a critical contributor to cardiovascular events in CKD. Beyond its established role in blood clotting and bone health, vitamin K appears crucial in regulating VC via vitamin K-dependent proteins (VKDPs). Among these, the matrix Gla protein (MGP) serves as both a potent inhibitor of VC and a valuable biomarker (in its inactive form) for reflecting circulating vitamin K levels. CKD patients, especially in advanced stages, often present with vitamin K deficiency due to dietary restrictions, medications, and impaired intestinal absorption in the uremic environment. Epidemiological studies confirm a strong association between vitamin K levels, inactive MGP, and increased CVD risk across CKD stages. Based on the promising results of pre-clinical data, an increasing number of clinical trials have investigated the potential benefits of vitamin K supplementation to prevent, delay, or even reverse VC, but the results have remained inconsistent.

The role of macrophage polarization in vascular calcification

Vascular calcification is an important factor in the high morbidity and mortality of Cardiovascular and cerebrovascular diseases. Vascular damage caused by calcification of the intima or media impairs the physiological function of the vascular wall. Inflammation is a central factor in the development of vascular calcification. Macrophages are the main inflammatory cells. Dynamic changes of macrophages with different phenotypes play an important role in the occurrence, progression and stability of calcification. This review focuses on macrophage polarization and the relationship between macrophages of different phenotypes and calcification environment, as well as the mechanism of interaction, it is considered that macrophages can promote vascular calcification by releasing inflammatory mediators and promoting the osteogenic transdifferentiation of smooth muscle cells and so on. In addition, several therapeutic strategies aimed at macrophage polarization for vascular calcification are described, which are of great significance for targeted treatment of vascular calcification.

Role of klotho and fibroblast growth factor 23 in arterial calcification, thickness, and stiffness: a meta-analysis of observational studies

This meta-analysis was conducted to clarify the role of klotho and fibroblast growth factor 23 (FGF-23) in human arterial remodeling across recent studies, in terms of arterial calcification, thickness, and stiffness. A systematic literature search was conducted on five databases for articles up to December 2023. Arterial calcification, thickness, and stiffness were determined using the calcification score and artery affected, carotid intima-media thickness (CIMT), and pulse wave velocity (PWV), respectively. Sixty-two studies with a total of 27,459 individuals were included in this meta-analysis. Most studies involved chronic kidney disease patients. Study designs were mostly cross-sectional with only one case-control and nine cohorts. FGF-23 was positively correlated with arterial calcification (r = 0.446 [0.254-0.611], p < 0.0001 and aOR = 1.36 [1.09-1.69], p = 0.006), CIMT (r = 0.188 [0.02-0.354], p = 0.03), and PWV (r = 0.235 [0.159-0.310], p < 0.00001). By contrast, Klotho was inversely correlated with arterial calcification (r = - 0.388 [- 0.578 to - 0.159], p = 0.001) and CIMT (r = - 0.38 [- 0.53 to - 0.207], p < 0.00001). In conclusion, FGF-23 and Klotho were associated with arterial calcification, thickness, and stiffness, clarifying their role in arterial remodeling processes.

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.

Novel Glycomimetics Protect against Glycated Low-Density Lipoprotein-Induced Vascular Calcification In Vitro via Attenuation of the RAGE/ERK/CREB Pathway

Heparan sulphate (HS) can act as a co-receptor on the cell surface and alterations in this process underpin many pathological conditions. We have previously described the usefulness of mimics of HS (glycomimetics) in protection against β-glycerophosphate-induced vascular calcification and in the restoration of the functional capacity of diabetic endothelial colony-forming cells in vitro. This study aims to investigate whether our novel glycomimetic compounds can attenuate glycated low-density lipoprotein (g-LDL)-induced calcification by inhibiting RAGE signalling within the context of critical limb ischemia (CLI). We used an established osteogenic in vitro vascular smooth muscle cell (VSMC) model. Osteoprotegerin (OPG), sclerostin and glycation levels were all significantly increased in CLI serum compared to healthy controls, while the vascular calcification marker osteocalcin (OCN) was down-regulated in CLI patients vs. controls. Incubation with both CLI serum and g-LDL (10 µg/mL) significantly increased VSMC calcification vs. controls after 21 days, with CLI serum-induced calcification apparent after only 10 days. Glycomimetics (C2 and C3) significantly inhibited g-LDL and CLI serum-induced mineralisation, as shown by a reduction in alizarin red (AR) staining and alkaline phosphatase (ALP) activity. Furthermore, secretion of the osteogenic marker OCN was significantly reduced in VSMCs incubated with CLI serum in the presence of glycomimetics. Phosphorylation of cyclic AMP response element-binding protein (CREB) was significantly increased in g-LDL-treated cells vs. untreated controls, which was attenuated with glycomimetics. Blocking CREB activation with a pharmacological inhibitor 666-15 replicated the protective effects of glycomimetics, evidenced by elevated AR staining. In silico molecular docking simulations revealed the binding affinity of the glycomimetics C2 and C3 with the V domain of RAGE. In conclusion, these findings demonstrate that novel glycomimetics, C2 and C3 have potent anti-calcification properties in vitro, inhibiting both g-LDL and CLI serum-induced VSMC mineralisation via the inhibition of LDLR, RAGE, CREB and subsequent expression of the downstream osteogenic markers, ALP and OCN.

Association of carotid intima-media thickness and dyslipidaemia in patients with type 2 diabetes: a protocol for systematic review and meta-analysis

INTRODUCTION

Patients with diabetes mellitus (DM) often present with comorbidities such as hypertension, dyslipidaemia, insulin resistance, obesity and hyperglycaemia, which increases their risk of cardiovascular diseases (CVDs)-related mortality. Carotid intima-media thickness (CIMT), a biomarker for subclinical atherosclerosis, has been associated with overall CVD, especially in type 2 DM (T2DM). Hence, this protocol for systematic review and meta-analysis aims to review existing literature on the association of CIMT and dyslipidaemia in patients with T2DM.

METHODS AND ANALYSIS

The proposed systematic review and meta-analysis will be conducted according to an updated Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Protocols guideline. A comprehensive search of peer-reviewed studies on Google Scholar, PubMed, Science Direct and Web of Sciences databases will be conducted up to 30 June 2023. A meta-analysis of data extracted from selected studies will be performed to explore the association between dyslipidaemia and CIMT in patients with diabetes. The effect estimates will be reported as standardised mean differences/Cohen's d and 95% CIs. A random effect model will be used in case of high heterogeneity whereas fixed-effect model will be used in the absence of heterogeneity. All statistical analysis will be performed using SPSS V.29.0 software. In cases of high heterogeneity, subgroup analysis will be performed based on study design, countries of publication and body mass index to identify potential sources of heterogeneity. Publication bias will be assessed graphically via funnel plots and statistically using Egger's regression test. Sensitivity analysis will also be performed to evaluate the stability of the overall effect size and the grading of recommendations assessment, development and evaluation will be used to grade the quality of analysed evidence.

ETHICS AND DISSEMINATION

As the proposed study will use secondary published data, approval will not be sought from the ethics committee.

PROSPERO REGISTRATION NUMBER

CRD42023451731.

D-box-binding protein alleviates vascular calcification in rats with chronic kidney disease by activating microRNA-195-5p and downregulating cyclin D1

Vascular calcification (VC) is a critical complication in chronic kidney disease (CKD), where transcription factors (TFs) and microRNAs (miRs) could potentially play a pivotal role in its pathogenesis and progression. To explore the potential molecular mechanism by which the TF D-box-binding protein (DBP) regulates the miR-195-5p/cyclin D1 (CCND1) axis and its impact on aortic VC in CKD rats, we established a rat model of CKD with VC through a 5/6 nephrectomy procedure. This model was treated with lentivirus overexpressing DBP or CCND1 to analyze their roles in aortic VC. Additionally, an in vitro cell model of VC was induced by high phosphorus. This model underwent transfection with lentivirus overexpressing DBP or miR-195-5p mimic/inhibitor to confirm their regulatory roles in aortic VC in vitro. We assessed the interactions between DBP and miR-195-5p, as well as between miR-195-5p and CCND1. Our results indicated that the expression of DBP and miR-195-5p was reduced, while CCND1 levels were elevated in both the rat and cell models.  Overexpression of miR-195-5p inhibited VC in vascular smooth muscle cells (VSMCs). Bioinformatics prediction and dual luciferase assays confirmed that DBP could act as a TF to enhance miR-195-5p expression, with Ccnd1 identified as a downstream target gene of miR-195-5p. Overexpression of DBP inhibited aortic calcification in CKD rats, whereas overexpression of CCND1 produced the opposite effect. In conclusion, the TF DBP can inhibit CCND1 expression through transcriptional activation of miR-195-5p, thereby preventing VC in rats with CKD.

VITAMIN D DEFICIENCY, BONE TURNOVER MARKERS AND ARTERIAL CALCIFICATIONS IN NON-DIALYSIS CHRONIC KIDNEY DISEASE PATIENTS

Introduction

Vitamin D [25(OH)D] deficiency is prevalent in chronic kidney disease (CKD), related to bone turnover and potentially involved in arterial calcifications.

Objective

To evaluate vitamin D status in non-dialysis CKD patients and its relationships with bone turnover markers (BTM) and arterial calcifications.

Design

Cross-sectional, prospective, multicentric study.

Subjects and methods

One hundred twenty-eight CKD patients (median age 61 years, 58% males, median eGFR 29mL/min) were included. Comorbidities, mineral and bone metabolism parameters were evaluated. Total alkaline phosphatase (T-ALP) was used to assess bone turnover. Atherosclerosis was evaluated by carotid intima-media thickness (CIMT), endothelial calcifications by aortic calcification score (ACS), and arterial stiffness by cardio-ankle vascular index (CAVI). Vitamin D deficiency was defined as 25(OH)D <15 ng/mL. Factors associated with vitamin D, T-ALP and vascular parameters were assessed in multivariate regression models.

Results

Prevalence of vitamin D deficiency was 63% and median 25(OH)D was 12.8 ng/mL. Older age, female sex and higher parathormone were predictors of vitamin D deficiency. Increased T-ALP was predicted by higher parathormone, suggesting high turnover bone disease. While age was a determinant of all evaluated vascular parameters, lower 25(OH)D was associated only with endothelial calcifications, which correlated with CAVI, suggesting a direct relation between vitamin D deficiency mediated plaques calcification and arterial stiffness.

Conclusion

Vitamin D deficiency was highly prevalent in this non-dialysis CKD cohort and was related to age, sex and parathormone. Vitamin D deficiency was associated with increased calcifications of endothelial plaques, which seemed to increase arterial stiffness.

Risk factors for the outcome after thrombolysis in acute ischemic stroke - the prominent role of kidney dysfunction: A retrospective cohort observational study

A complex interplay of factors reflecting the general biological, cardiovascular, neurological, renal, and metabolic status of patients influences the outcome of thrombolysis in stroke patients. This is a retrospective cohort observational study aimed to determine the importance of kidney dysfunction among these factors. Data (demographic, lifestyle, physical examination, laboratory, imaging, including metabolic and cardiovascular risk factors and comorbidities, neurological scores, and outcomes) of all stroke patients who underwent thrombolysis have been registered since January 1, 2016, in an online database. A total of 296 patients registered until December 31, 2020, were included in the study. The National Institutes of Health Stroke Scale, modified Rankin scale, Barthel index, percentage of hemorrhagic transformation, and in hospital death were used to evaluate the neurological status and outcomes of the patients. Regression analysis, Mann-Whitney test, Fisher exact test, logistic regression, and multivariate analysis were used for statistical analysis. Kidney dysfunction, as reflected by the estimated glomerular filtration rate, was associated with in hospital death and all but one of the neurological scores. Other risk factors most frequently associated with neurological scores were age, international normalized ratio, and cognitive decline. Multivariate analysis revealed estimated glomerular filtration rate (as determined by chronic kidney disease-EPI equation) as a determinant for all but one of these scores, and as the most important determinant for most of them, except for those reflecting the pre-intervention neurological status of the patient. Kidney dysfunction seems to be the most important determinant of the outcome of thrombolysed stroke patients, a result obtained by no other study.

Clinical Significance of Adropin and Afamin in Evaluating Renal Function and Cardiovascular Health in the Presence of CKD-MBD Biomarkers in Chronic Kidney Disease

AIM

The study aims to test the hypothesis that concentrations of adropin and afamin differ between patients in various stages of chronic kidney disease when compared with healthy controls. The study also investigates the association of the biomarkers (adropin and afamin) with CKD-MBD and traditional cardiovascular risk parameters in CKD patients.

METHODOLOGY

The cross-sectional study includes the subjects divided into four groups comprising the control group (healthy volunteers = 50), CKD stages 1-2 patients (n = 50), CKD stages 3-4 patients (n = 50), CKD stage 5 patients (n = 50). Serum concentrations of adropin and afamin were determined using ELISA. Clinical variables (renal, lipid, and CKD-MBD parameters) were correlated to adropin and afamin concentrations.

RESULTS

Afamin concentration was found to be higher in group IV, followed by groups III and II when compared to the control group, i.e., (83.243 ± 1.46, 64.233 ± 0.99, and 28.948 ± 0.72 vs. 14.476 ± 0.5) mg/L (p < 0.001), and adropin concentration was found to be lower in group IV as compared to groups III, II, and I (200.342 ± 8.37 vs. 284.682 ± 9.89 vs. 413.208 ± 12.32 vs. 706.542 ± 11.32) pg/mL (p < 0.001), respectively. Pearson correlation analysis showed that afamin was positively correlated with traditional cardiovascular risk biomarkers, while adropin showed a negative correlation.

CONCLUSIONS

Adropin and afamin may potentially serve as futuristic predictors for the deterioration of renal function and may be involved in the pathological mechanisms of CKD and its associated complications such as CKD-MBD and high lipid levels.

Association between estimated glomerular filtration rate slope and cardiovascular disease among individuals with and without diabetes: a prospective cohort study

BACKGROUND

Previous studies have reported an association between a significant decline in estimated glomerular filtration rate (eGFR) over time and an increased risk of cardiovascular disease (CVD). This study aimed to investigate the association between the eGFR slope and CVD among individuals with and without diabetes.

METHODS

This prospective cohort study was conducted within the Tehran Lipid and Glucose Study (TLGS) framework. We studied 6919 adults aged 20-70 years, including 985 with diabetes and 5934 without diabetes. The eGFR slope was determined based on repeated measurements of eGFR through linear mixed-effects models. A multivariable Cox proportional hazard model was employed to evaluate the association between eGFR slope, both in continuous and categorical form, and the risk of CVD.

RESULTS

The slopes of eGFR exhibited a bell-shaped distribution, with a mean (standard deviation (SD)) of -0.63 (0.13) and - 0.70 (0.14) ml/min per 1.73 m2 per year in individuals with and without diabetes, respectively. During a median follow-up of 8.22 years, following the 9-year eGFR slope ascertainment period, a total of 551 CVD events (195 in patients with diabetes) were observed. Among individuals with diabetes, a steeper decline in eGFR slope was significantly associated with a higher risk of CVD events, even after adjusting for baseline eGFR, demographic factors, and traditional risk factors for CVD; slopes of (-1.05 to -0.74) and (-0.60 to -0.52) were associated with 2.12 and %64 higher risks for CVD, respectively, compared with a slope of (-0.51 to 0.16). Among individuals without diabetes, the annual eGFR slope did not show a significant association with the risk of CVD.

CONCLUSION

Monitoring the eGFR slope may serve as a potential predictor of CVD risk in individuals with diabetes.

Significance of Kidney Disease in Cardiovascular Disease Patients

Cardiorenal syndrome is a condition where is a bidirectional and mutually detrimental relationship between the heart and kidneys. The mechanisms underlying cardiorenal syndrome are multifactorial and complex. Patients with kidney disease exhibit increased cardiovascular risk, presenting as coronary and peripheral artery disease, structural heart disease, arrhythmias, heart failure, and sudden cardiac death, largely occurring because of a systemic proinflammatory state, causing myocardial and vascular remodeling, manifesting as atherosclerotic lesions, vascular and valvular calcification, and myocardial fibrosis, particularly among those with advanced disease. This review summarizes the current understanding and clinical implications of kidney disease in patients with cardiovascular disease.

[Long noncoding RNA H19 promotes vascular calcification by repressing the Bax inhibitor 1/optic atrophy 1 pathway]

OBJECTIVE

To investigate whether long noncoding RNA H19 (lncRNA H19) induces vascular calcification by promoting calcium deposition, osteogenic differentiation and apoptosis via inhibiting the Bax inhibitor 1/optic atrophy 1 (BI-1/ OPA1) pathway.

METHODS

β-glycerophosphate and calcium chloride were used to induce calcification in rat vascular smooth muscle cells (VSMCs), and the effects of siH19, alone or in combination with BI-1 or OPA1 knockdown, on calcification of the cells were investigated. Osteogenic differentiation was assessed by measuring Runt-related transcription factor 2 (Runx-2) and bone morphogenetic protein 2 (BMP-2) expression with Western blotting, and cell apoptosis was evaluated by TUNEL staining and Western blotting. An ApoE-/- diabetic mouse model with high-fat feeding for 32 weeks were given an intraperitoneal injection of siH19, and the changes in calcium deposition in the aortic arch were examined using Alizarin red S staining and von Kossa staining.

RESULTS

In rat VSMCs with calcification, the expression of lncRNA H19 was significantly increased, and the expressions of BI- 1 and OPA1 were significantly decreased. Downregulation of lncRNA H19 significantly increased the expressions of BI-1 and OPA1 proteins in the cells, and BI-1 knockdown further reduced OPA1 expression (P<0.001). The cells treated with siH19 showed total disappearance of the calcified nodules with significantly reduced expressions of Runx-2, BMP-2 and cleaved caspase-3 and a lowered cell apoptosis rate (P<0.001). Calcified nodules were again observed in the cells with lncRNA H19 knockdown combined with BI-1 or OPA1 knockdown, and the expressions of Runx-2, BMP-2, cleaved-caspase-3 and cell apoptosis rate all significantly increased (P<0.001). In the diabetic mouse model with high-fat feeding, siH19 treatment significantly reduced the calcification area and increased mRNA expressions of BI-I and OPA1 in the aortic arch.

CONCLUSION

LncRNA H19 promotes vascular calcification possibly by promoting calcium deposition, osteogenic differentiation and cell apoptosis via inhibiting the BI-1/OPA1 pathway.

Salt-Sensitive Hypertension: Mediation by Salt-Induced Hypervolemia and Phosphate-Induced Vascular Calcification

Preventing hypertension by restricting dietary salt intake, sodium chloride, is well established in public health policy, but a pathophysiological mechanism has yet to explain the controversial clinical finding that some individuals have a greater risk of hypertension from exposure to salt intake, termed salt-sensitive hypertension. The present perspective paper synthesizes interdisciplinary findings from the research literature and offers novel insights proposing that the pathogenesis of salt-sensitive hypertension is mediated by interaction of salt-induced hypervolemia and phosphate-induced vascular calcification. Arterial stiffness and blood pressure increase as calcification in the vascular media layer reduces arterial elasticity, preventing arteries from expanding to accommodate extracellular fluid overload in hypervolemia related to salt intake. Furthermore, phosphate has been found to be a direct inducer of vascular calcification. Reduction of dietary phosphate may help reduce salt-sensitive hypertension by lowering the prevalence and progression of vascular calcification. Further research should investigate the correlation of vascular calcification with salt-sensitive hypertension, and public health recommendations to prevent hypertension should encourage reductions of both sodium-induced hypervolemia and phosphate-induced vascular calcification.

Impaired renal ischemia reperfusion recovery after bilateral renal artery ligation in rats treated with adenine: role of renal mitochondria

Vascular calcification (VC) and ischemia reperfusion (IR) injury is characterised to have mitochondrial dysfunction. However, the impact of dysfunctional mitochondria associated with vascular calcified rat kidney challenged to IR is not explored and is addressed in the present study. Male Wistar rats were treated with adenine for 20 days to induce chronic kidney dysfunction and VC. After 63 days, renal IR protocol was performed with subsequent recovery for 24 h and 7 days. Various mitochondrial parameters and biochemical assays were performed to assess kidney function, IR injury and its recovery. Adenine-induced rats with VC, decreased creatinine clearance (CrCl), and severe tissue injury demonstrated an increase in renal tissue damage and decreased CrCl after 24 h of IR (CrCl in ml: IR-0.220.02, VC-IR-0.050.01). Incidentally, the 24 h IR pathology in kidney was similar in both VC-IR and normal rat IR. But, the magnitude of dysfunction was higher with VC-IR due to pre-existing basal tissue alterations. We found severed deterioration in mitochondrial quantity and quality supported by low bioenergetic function in both VC basal tissue and IR challenged sample. However, post 7 days of IR, unlike normal rat IR, VC rat IR did not improve CrCl and corresponding mitochondrial damage in terms of quantity and its function were observed. Based on the above findings, we conclude that IR in VC rat adversely affect the post-surgical recovery, mainly due to the ineffective renal mitochondrial functional restoration from the surgery.

Associations of Breast Arterial Calcifications with Cardiovascular Disease

Cardiovascular diseases (CVD), including coronary artery disease (CAD), continue to be the leading cause of global mortality among women. While traditional CVD/CAD prevention tools play a significant role in reducing morbidity and mortality among both men and women, current tools for preventing CVD/CAD rely on traditional risk factor-based algorithms that often underestimate CVD/CAD risk in women compared with men. In recent years, some studies have suggested that breast arterial calcifications (BAC), which are benign calcifications seen in mammograms, may be linked to CVD/CAD. Considering that millions of women older than 40 years undergo annual screening mammography for breast cancer as a regular activity, innovative risk prediction factors for CVD/CAD involving mammographic data could offer a gender-specific and convenient solution. Such factors that may be independent of, or complementary to, current risk models without extra cost or radiation exposure are worthy of detailed investigation. This review aims to discuss relevant studies examining the association between BAC and CVD/CAD and highlights some of the issues related to previous studies' design such as sample size, population types, method of assessing BAC and CVD/CAD, definition of cardiovascular events, and other confounding factors. The work may also offer insights for future CVD risk prediction research directions using routine mammograms and radiomic features other than BAC such as breast density and macrocalcifications.

Proton Pump Inhibitors and Risk of Chronic Kidney Disease: Evidence from Observational Studies

Previous epidemiological studies have raised the concern that the use of proton pump inhibitors (PPIs) is associated with an increased risk of kidney diseases. To date, no comprehensive meta-analysis has been conducted to assess the association between PPIs and the risk of chronic kidney disease (CKD). Therefore, we conducted a systematic review and meta-analysis to address the association between PPIs and CKD. The primary search was conducted in the most popular databases, such as PubMed, Scopus, and Web of Science. All observational studies evaluated the risk of CKD among PPI users, and non-users were considered for inclusion. Two reviewers conducted data extraction and assessed the risk of bias. Random-effect models were used to calculate pooled effect sizes. A total of 6,829,905 participants from 10 observational studies were included. Compared with non-PPI use, PPI use was significantly associated with an increased risk of CKD (RR 1.72, 95% CI: 1.02-2.87, p = 0.03). This updated meta-analysis showed that PPI was significantly associated with an increased risk of CKD. Association was observed in the same among moderate-quality studies. Until further randomized control trials (RCTs) and biological studies confirm these results, PPI therapy should not stop patients with gastroesophageal reflux disease (GERD). However, caution should be used when prescribing to patients with high-risk kidney disease.

Aortic Stenosis and Aortic Valve Replacement among Patients with Chronic Kidney Disease: A Narrative Review

BACKGROUND

Aortic stenosis (AS) can present with dyspnea, angina, syncope, and palpitations, and this presents a diagnostic challenge as chronic kidney disease (CKD) and other commonly found comorbid conditions may present similarly. While medical optimization is an important aspect in management, aortic valve replacement (AVR) by surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR) is the definitive treatment. Patients with concomitant CKD and AS require special consideration as it is known that CKD is associated with progression of AS and poor long-term outcomes.

AIMS AND OBJECTIVES

The aim of the study was to summarize and review the current existing literature on patients with both CKD and AS regarding disease progression, dialysis methods, surgical intervention, and postoperative outcomes.

CONCLUSION

The incidence of AS increases with age but has also been independently associated with CKD and furthermore with hemodialysis (HD). Regular dialysis with HD versus peritoneal dialysis (PD) and female gender have been associated with progression of AS. Management of AS is multidisciplinary and requires planning and interventions by the heart-kidney team to decrease the risk of further inducing kidney injury among high-risk population. Both TAVR and SAVR are effective interventions for patients with severe symptomatic AS, but TAVR has been associated with better short-term renal and cardiovascular outcomes.

IMPLICATIONS FOR PRACTICE

Special consideration must be given to patients with both CKD and AS. The choice of whether to undergo HD versus PD among patients with CKD is multifactorial, but studies have shown benefit regarding AS progression among those who undergo PD. The choice regarding AVR approach is likewise the same. TAVR has been associated with decreased complications among CKD patients, but the decision is multifactorial and requires a comprehensive discussion with the heart-kidney team as many other factors play a role in the decision including preference, prognosis, and other risk factors.

The pathophysiology and management of vascular calcification in chronic kidney disease patients

INTRODUCTION

Vascular calcification (VC) which is the pathological mineral deposition in the vascular system, predominantly at the intimal and medial layer of the vessel wall, is an important comorbidity in patients with chronic kidney disease (CKD) leading to significant morbidity and mortality while necessitating appropriate treatment. Our review aims to provide an in-depth analysis of the current understanding of VC.

AREAS COVERED

In this review, we first discuss the pathophysiology of VC in CKD patients, then we explain the methods to predict and assess VC. Afterwards, we provide the currently available as well as the potential therapeutic approaches of VC. We finally discuss our understanding regarding the current situation surrounding VC in our expert opinion section.

EXPERT OPINION

Predicting, assessing and treating VC is crucial and the future advances in the field of research surrounding VC will potentially occur in one or more of these three areas of clinical management. There is a current lack of evidence and consensus regarding specific therapeutic options for alleviating VC and this situation may not necessitate VC to be determined, detected, and documented before the available options are implemented. Regardless, the prediction and assessment of VC is still important and requires further improvement together with the developments in therapeutic alternatives. The future has the potential to bring better research which would guide and improve the management of this patient group. A more specialized approach consisting of targeted therapies and more tailored management plans for patients with CKD and VC is on the horizon.

Six Decades of History of Hypertension Research at the University of Toledo: Highlighting Pioneering Contributions in Biochemistry, Genetics, and Host-Microbiota Interactions

PURPOSE OF REVIEW

The study aims to capture the history and lineage of hypertension researchers from the University of Toledo in Ohio and showcase their collective scientific contributions dating from their initial discoveries of the physiology of adrenal and renal systems and genetics regulating blood pressure (BP) to its more contemporary contributions including microbiota and metabolomic links to BP regulation.

RECENT FINDINGS

The University of Toledo College of Medicine and Life Sciences (UTCOMLS), previously known as the Medical College of Ohio, has contributed significantly to our understanding of the etiology of hypertension. Two of the scientists, Patrick Mulrow and John Rapp from UTCOMLS, have been recognized with the highest honor, the Excellence in Hypertension award from the American Heart Association for their pioneering work on the physiology and genetics of hypertension, respectively. More recently, Bina Joe has continued their legacy in the basic sciences by uncovering previously unknown novel links between microbiota and metabolites to the etiology of hypertension, work that has been recognized by the American Heart Association with multiple awards. On the clinical research front, Christopher Cooper and colleagues lead the CORAL trials and contributed importantly to the investigations on renal artery stenosis treatment paradigms. Hypertension research at this institution has not only provided these pioneering insights, but also grown careers of scientists as leaders in academia as University Presidents and Deans of Medical Schools. Through the last decade, the university has expanded its commitment to Hypertension research as evident through the development of the Center for Hypertension and Precision Medicine led by Bina Joe as its founding Director. Hypertension being the top risk factor for cardiovascular diseases, which is the leading cause of human mortality, is an important area of research in multiple international universities. The UTCOMLS is one such university which, for the last 6 decades, has made significant contributions to our current understanding of hypertension. This review is a synthesis of this rich history. Additionally, it also serves as a collection of audio archives by more recent faculty who are also prominent leaders in the field of hypertension research, including John Rapp, Bina Joe, and Christopher Cooper, which are cataloged at Interviews .

The association between weight-adjusted-waist index and abdominal aortic calcification in adults aged ≥ 40 years: results from NHANES 2013-2014

The negative effects of obesity on the cardiovascular health have drawn much attention. Weight-adjusted-waist index (WWI) has been proved to reflect weight-independent centripetal obesity. However, the association between WWI and abdominal aortic calcification (AAC) has not been reported before. Using data from National Health and Nutrition Examination Survey 2013-2014, we aimed to determine the relationship of WWI and AAC in adults aged ≥ 40 years. WWI was determined by dividing waist circumference by the square root of weight. AAC was measured by dual-energy X-ray absorptiometry and quantified by Kauppila scores. Severe AAC (SAAC) was defined as an AAC score > 6. We utilized weighed multivariable logistic regression and generalized additive model to explore the independent association between WWI and AAC. Threshold effects were further calculated by two-piecewise linear regression model. 3082 participants were enrolled in our analysis, of which 48.2% were male. WWI was positively associated with AAC scores (β = 0.34, 95% CI 0.05-0.63) and exhibited a nonlinear relationship with SAAC. On the left of the breakpoint (WWI = 11.11), WWI and SAAC were positively associated (OR = 2.86, 95% CI 1.40-5.84), while no such relationship was found on the right (OR = 1.07, 95% CI 0.77-1.48). Our findings indicated that WWI may serve as a simple biomarker of AAC in US adults aged ≥ 40 years.

Vascular Calcification: In Vitro Models under the Magnifying Glass

Vascular calcification is a systemic disease contributing to cardiovascular morbidity and mortality. The pathophysiology of vascular calcification involves calcium salt deposition by vascular smooth muscle cells that exhibit an osteoblast-like phenotype. Multiple conditions drive the phenotypic switch and calcium deposition in the vascular wall; however, the exact molecular mechanisms and the connection between vascular smooth muscle cells and other cell types are not fully elucidated. In this hazy landscape, effective treatment options are lacking. Due to the pathophysiological complexity, several research models are available to evaluate different aspects of the calcification process. This review gives an overview of the in vitro cell models used so far to study the molecular processes underlying vascular calcification. In addition, relevant natural and synthetic compounds that exerted anticalcifying properties in in vitro systems are discussed.

Atherosclerosis Specific Features in Chronic Kidney Disease (CKD)

Atherosclerosis is the major cause of cardiovascular disease, leading to a high mortality rate worldwide. Several risk factors are known to favor atherogenesis, among which are high blood pressure, smoking, diabetes mellitus, and others. Chronic kidney disease is another serious health problem associated with significant health care costs, morbidity, and mortality. Chronic kidney disease shares several risk factors with atherosclerosis and cardiovascular diseases, such as hypertension and diabetes mellitus. Additional risk factors for cardiovascular disease development should be considered in patients with chronic kidney disease. Interestingly, patients suffering from chronic kidney disease are more prone to cardiovascular problems than the general population. Moreover, chronic kidney disease is characterized by an increased atherosclerotic burden from the very early stages. The purpose of this review was to summarize data on atherosclerosis in chronic kidney disease, highlighting the specific features of the disease combination.

The kidney reabsorption-related Magnesium Depletion Score is associated with increased likelihood of abdominal aortic calcification among US adults

BACKGROUND

Kidney reabsorption has a vital role in magnesium homeostasis. This study aimed to determine the relationship between the kidney reabsorption-related magnesium depletion score (MDS) and abdominal aortic calcification (AAC).

METHODS

We obtained the data of 2640 individuals from the National Health and Nutrition Examination Survey (NHANES) database and analyzed the relationship between MDS and AAC scores. MDS is a scoring system developed to predict status of magnesium deficiency that fully considered the pathophysiological factors influencing the kidneys' reabsorption capability. AAC was quantified by the Kauppila score system based on dual-energy X-ray absorptiometry. We performed stratified analysis and multiple equation regression analysis. R and EmpowerStats were used for data analysis.

RESULTS

A total of 2640 participants were included with the mean AAC score of 1.47 ± 0.07. Participants in higher MDS tended to have higher AAC scores (MDS scored 0: 0.75 (0.56, 0.93), MDS scored 1: 1.02 (0.84, 1.21), MDS scored 2: 2.34 (1.80, 2.87), MDS scored 3: 3.19 (2.46, 3.92), MDS ≥ 4: 4.99 (3.49, 6.49)). Compared with those in the lowest MDS scored 0, the highest subgroup (MDS ≥ 4) was associated with a higher AAC score (β = 4.24, 95% CI: 2.78-5.70, p < 0.001), and the association was not altered (β = 1.81, 95% CI: 0.54-3.09, p = 0.002) after adjusting for numerous covariates. Subgroup analyses showed that stronger associations between MDS and AAC score were detected in adults with lower levels of magnesium intake and older (all p for interaction < 0.05).

CONCLUSIONS

The MDS is a promising tool for identifying individuals with magnesium deficiency status who may benefit from dietary magnesium supplementation to reduce the risks of AAC.

Dirty Jobs: Macrophages at the Heart of Cardiovascular Disease

Cardiovascular disease (CVD) is one of the greatest public health concerns and is the leading cause of morbidity and mortality in the United States and worldwide. CVD is a broad yet complex term referring to numerous heart and vascular conditions, all with varying pathologies. Macrophages are one of the key factors in the development of these conditions. Macrophages play diverse roles in the maintenance of cardiovascular homeostasis, and an imbalance of these mechanisms contributes to the development of CVD. In the current review, we provide an in-depth analysis of the diversity of macrophages, their roles in maintaining tissue homeostasis within the heart and vasculature, and the mechanisms through which imbalances in homeostasis may lead to CVD. Through this review, we aim to highlight the potential importance of macrophages in the identification of preventative, diagnostic, and therapeutic strategies for patients with CVD.

A Reproducible Mouse Model of Moderate CKD With Early Manifestations of Osteoblastic Transition of Cardiovascular System

Chronic kidney disease (CKD) is a significant public health challenge with a substantial associated risk of mortality, morbidity, and health care expenditure. Culprits that lead to development and progression of CKD are multifaceted and heterogenous in nature. This notion underscores the need for diversification of animal models to investigate its pathophysiology, related complications, and to subsequently enable discovery of novel therapeutics. Importantly, animal models that could recapitulate complications of CKD in both genders are desperately needed. Cardiovascular disease is the most common cause of death in CKD patients that may be due in part to high prevalence of vascular calcification (VC). Using DBA/2 mice that are susceptible to development of VC, we sought to investigate the feasibility and reproducibility of a unilateral ischemia-reperfusion model followed by contralateral nephrectomy (UIRI/Nx) to induce CKD and its related complications in female and male mice. Our results demonstrate that irrespective of gender, mice faithfully displayed complications of moderate CKD following UIRI/Nx as evidenced by significant rise in serum creatinine, albuminuria, higher degree of collagen deposition, elevated expression of classic fibrotic markers, higher circulating levels of FGF-23, PTH and hepcidin. Moreover, we corroborate the osteoblastic transition of aortic smooth muscle cells and cardiomyocytes based on higher levels of osteoblastic markers namely, Cbfa-1, osteopontin, osteocalcin, and osterix. Our data confirms a viable, and consistent model of moderate CKD and its associated complications in both male and female mice. Furthermore, early evidence of osteoblastic transition of cardiovascular system in this model confirms its suitability for studying and implementing potential preventive and/or therapeutic approaches that are urgently needed in this field.

Vascular Calcification in Chronic Kidney Disease: Distinct Features of Pathogenesis and Clinical Implication

Chronic kidney disease (CKD) is associated with a higher prevalence of vascular calcification (VC) and cardiovascular disease. VC in CKD patients showed different pathophysiological features from those of the general population. The pathogenesis of VC in CKD is a highly organized process, and prior studies have suggested that patients with CKD have their own specific contributors to the phenotypic change of vascular smooth muscle cells (VSMCs), including uremic toxins, CKD-mineral and bone disease (CKD-MBD), inflammation, and oxidative stress. For the diagnosis and monitoring of VC in CKD, several imaging modalities, including plain radiography, ultrasound, and computed tomography have been utilized. VC in CKD patients has distinct clinical features and implications. CKD patients revealed a more intense and more prevalent calcification on the intimal and medial layers, whereas intimal calcification is predominantly observed in the general population. While a higher VC score is clearly associated with a higher risk of all-cause mortality and cardiovascular events, a greater VC score in CKD patients does not fully reflect the burden of atherosclerosis, because they have more calcification at equal volumes of atheromatous plaques. The primary goal of VC treatment in CKD is the prevention of VC progression, and the main management is to control the biochemical components of CKD-MBD. Cinacalcet and non-calcium-containing phosphate binders are the mainstay of VC prevention in CKD-MBD management. VC in patients with CKD is an ongoing area of research and is expected to advance soon.

Toxic Effects of Indoxyl Sulfate on Osteoclastogenesis and Osteoblastogenesis

Uremic toxins, such as indoxyl sulfate (IS) and kynurenine, accumulate in the blood in the event of kidney failure and contribute to further bone damage. To maintain the homeostasis of the skeletal system, bone remodeling is a persistent process of bone formation and bone resorption that depends on a dynamic balance of osteoblasts and osteoclasts. The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that regulates the toxic effects of uremic toxins. IS is an endogenous AhR ligand and is metabolized from tryptophan. In osteoclastogenesis, IS affects the expression of the osteoclast precursor nuclear factor of activated T cells, cytoplasmic 1 (NFATc1) through AhR signaling. It is possible to increase osteoclast differentiation with short-term and low-dose IS exposure and to decrease differentiation with long-term and/or high-dose IS exposure. Coincidentally, during osteoblastogenesis, through the AhR signaling pathway, IS inhibits the phosphorylation of ERK, and p38 reduces the expression of the transcription factor 2 (Runx2), disturbing osteoblastogenesis. The AhR antagonist resveratrol has a protective effect on the IS/AhR pathway. Therefore, it is necessary to understand the multifaceted role of AhR in CKD, as knowledge of these transcription signals could provide a safe and effective method to prevent and treat CKD mineral bone disease.