Process Of Vascular Calcification Research Articles

#899 The effect of exercise training on microRNAs in patients undergoing hemodialysis

Abstract Background and Aims Physical inactivity is a risk factor for mortality and morbidity in patients undergoing hemodialysis (HD). Therefore, physical exercise (PE) is recommended as part of the management of HD patients. Although the benefits of PE for HD patients have been well documented in the literature, the pathophysiological mechanism still needs to be fully understood. Recently, microRNAs (miRNAs) have come to light as potential mediators of PE's therapeutic effects in healthy individuals. Currently, no information is available about how PE affects the expression of miRNAs in HD patients, mainly for osteogenic differentiation, a critical process in forming vascular calcification. Therefore, this observational longitudinal study aims to assess the expression of miR-9 and miR-30b, two regulators of the osteogenic commitment from endothelial progenitor cells, in HD patients engaged in an interdialytic exercise program. Method Male HD patients aged between 50 and 80 could walk for at least six meters were enrolled. Exclusion criteria were uncorrected anemia, acute infectious disease, uncontrolled hyperparathyroidism, active oncologic disease, and severe cardio-respiratory, musculoskeletal, or neurological conditions inhibiting exercise training. Patients were engaged in a structured interdialytic program supervised by an exercise facilitator. Exercise training was performed at home or the dialysis centre based on the patient's needs and preferences. It consisted of a 10-minute session/day of low-intensity walking and/or resistance exercises. The speed was increased weekly and controlled with a metronome application on the patient's smartphone. The maximum distance covered evaluates the patients' physical performance, as measured by the 6-minute walking test (6MWT). It was assessed at baseline and the 6-month follow-up. Blood samples for miRNA analysis were collected during the short interdialytic period at baseline and at the 6-month follow-up. MiRNAs will be extracted from serum samples using the miRNeasy Serum/Plasma Advanced Kit. Statistical analysis will be performed using SPSS 21.0. The difference between the two groups was assessed using a t-test for paired data. P-values<0.05 were considered statistically significant. Results Patients’ characteristics at baseline are shown in Table 1. Five patients were enrolled in the study, three undergoing exercise training at the dialysis centre and two at home. At six months, miR-30b expression appeared significantly upregulated in all patients (p<0.03) (Fig. 1). At the same time, the upregulation of miR-9 did not reach significance (p = 0.07). In one patient, miR-9 was not detected (Fig. 2). The mean distance covered during the 6MWT did not improve at six months (255 ± 129 meters) compared to baseline (235 ± 118 meters) (p = 0.49). Conclusion Preliminary results of this longitudinal observational study show that miR-30b was upregulated in patients engaged in the exercise training period at the 6-month follow-up despite no improvement in physical performance. The upregulation of miR-30b levels can potentially reduce the dedifferentiation of vascular smooth muscle cells into an osteoblastic-like phenotype. At the end of our study, novel evidence concerning the potential effect of exercise training on miRNA expressions correlated to the vascular calcification process in HD patients will be available.

WCN24-62 Identification of an inhibitor of vascular calcification processes

WCN24-62 Identification of an inhibitor of vascular calcification processes

Association between BMD and coronary artery calcification: an observational and Mendelian randomization study.

Observational studies have reported inconsistent associations between bone mineral density (BMD) and coronary artery calcification (CAC). We examined the observational association of BMD with CAC in 2 large population-based studies and evaluated the evidence for a potential causal relation between BMD and CAC using polygenic risk scores (PRS), 1- and 2-sample Mendelian randomization (MR) approaches. Our study populations comprised 1414 individuals (mean age 69.9yr, 52.0% women) from the Rotterdam Study and 2233 individuals (mean age 56.5yr, 50.9% women) from the Framingham Heart Study with complete information on CAC and BMD measurements at the total body (TB-), lumbar spine (LS-), and femoral neck (FN-). We used linear regression models to evaluate the observational association between BMD and CAC. Subsequently, we compared the mean CAC across PRSBMD quintile groups at different skeletal sites. In addition, we used the 2-stage least squares regression and the inverse variance weighted (IVW) model as primary methods for 1- and 2-sample MR to test evidence for a potentially causal association. We did not observe robust associations between measured BMD levels and CAC. These results were consistent with a uniform random distribution of mean CAC across PRSBMD quintile groups (P-value > .05). Moreover, neither 1- nor 2-sample MR supported the possible causal association between BMD and CAC. Our results do not support the contention that lower BMD is (causally) associated with an increased CAC risk. These findings suggest that previously reported epidemiological associations of BMD with CAC are likely explained by unmeasured confounders or shared etiology, rather than by causal pathways underlying both osteoporosis and vascular calcification processes.

Phenotypic switching of vascular smooth muscle cells in atherosclerosis, hypertension, and aortic dissection.

Vascular smooth muscle cells (VSMCs) play a critical role in regulating vasotone, and their phenotypic plasticity is a key contributor to the pathogenesis of various vascular diseases. Two main VSMC phenotypes have been well described: contractile and synthetic. Contractile VSMCs are typically found in the tunica media of the vessel wall, and are responsible for regulating vascular tone and diameter. Synthetic VSMCs, on the other hand, are typically found in the tunica intima and adventitia, and are involved in vascular repair and remodeling. Switching between contractile and synthetic phenotypes occurs in response to various insults and stimuli, such as injury or inflammation, and this allows VSMCs to adapt to changing environmental cues and regulate vascular tone, growth, and repair. Furthermore, VSMCs can also switch to osteoblast-like and chondrocyte-like cell phenotypes, which may contribute to vascular calcification and other pathological processes like the formation of atherosclerotic plaques. This provides discusses the mechanisms that regulate VSMC phenotypic switching and its role in the development of vascular diseases. A better understanding of these processes is essential for the development of effective diagnostic and therapeutic strategies.

In vitro Evaluation of the Calcification Inhibitory Properties of Policosanol, Genistein, and Vitamin D (Reduplaxin®) either Alone or in Combination.

The process of vascular calcification has severe clinical consequences in a number of diseases, including diabetes, atherosclerosis, and end-stage renal disease. In the present study, we investigated the effect of policosanol (Poli), genistein (Gen), and vitamin D (VitD) separately and in association to evaluate the possible synergistic action on inorganic phosphate (Pi)-induced calcification of vascular smooth muscle cells (VSMCs). Primary human VSMCs were cultured with either growth medium or growth medium supplemented with calcium and phosphorus (calcification medium) in combination with Poli, Gen, and VitD. Alizarin Red staining, mineralization, and the protein expression of RUNX2 and superoxide dismutase-2 (SOD2) were investigated. All three substances tested were effective at reducing osteogenic differentiation of VSMCs in a dose-dependent manner. Poli+Gen, Poli+VitD, Gen+VitD treatment induced a greater inhibition of calcification and RUNX2 expression compared to single compounds treatments. Moreover, the association of Poli+Gen+VitD (Reduplaxin®) was more effective at inhibiting VSMCs mineralization and preventing the increase in RUNX2 expression induced by calcification medium but not modified SOD2 expression. The association of Pol, Gen, and VitD (Reduplaxin®) has an additive inhibitory effect on the calcification process of VSMCs induced in vitro by a pro-calcifying medium.

The functional role of cellular senescence during vascular calcification in chronic kidney disease.

Vascular calcification (VC) has emerged as a key predictor of cardiovascular events in patients with chronic kidney disease (CKD). In recent years, an expanding body of research has put forth the concept of accelerated vascular aging among CKD patients, highlighting the significance of vascular cells senescence in the process of VC. Within the milieu of uremia, senescent vascular endothelial cells (VECs) release extracellular microvesicles (MV) that promote vascular smooth muscle cells (VSMCs) senescence, thereby triggering the subsequent osteogenic phenotypic switch and ultimately contributing to the VC process. In addition, senescent vascular progenitor or stem cells with diminished ability to differentiate into VECs and VSMCS, compromise the repair of vascular integrity, on the other hand, release a cascade of molecules associated with senescence, collectively known as the senescence-associated secretory phenotype (SASP), perpetuating the senescence phenomenon. Furthermore, SASP triggers the recruitment of monocytes and macrophages, as well as adjacent VECs and VSMCs into a pro-adhesive and pro-inflammatory senescent state. This pro-inflammatory microenvironment niche not only impacts the functionality of immune cells but also influences the differentiation of myeloid immune cells, thereby amplifying the reduced ability to effectively clear senescent cells of senescent macrophages, promoted calcification of VSMCs. The objective of this paper is to provide a comprehensive review of the contribution of vascular cell senescence to the emergence and advancement of VC. Gaining a comprehensive understanding of the involvement of cellular senescence within the vessel wall is pivotal, especially when it comes to its intersection with VC. This knowledge is essential for advancing groundbreaking anti-aging therapies, aiming to effectively mitigate cardiovascular diseases.

Lumican silencing ameliorates β-glycerophosphate-mediated vascular smooth muscle cell calcification by attenuating the inhibition of APOB on KIF2C activity.

Adverse cardiovascular events are associated with vascular calcification (VC) process, where vascular smooth muscle cells (VSMCs) differentiate into osteoblastic phenotype and deposit hydroxyapatite crystals. Microtubule-associated protein kinesin family member 2C (KIF2C) expression is decreased obviously in VSMC during calcification induction. Accordingly, we investigate the role and potential mechanism of KIF2C on VSMC calcification. The effects of β-glycerophosphate (β-GP)/KIF2C/lumican (LUM) on calcification, calcium content, alkaline phosphatase (ALP) activity, calcification-related markers, Tubulin, the ratio of polymerized (Po) to free (Fr) tubulin, as well as levels of LUM, apolipoprotein B (APOB), and KIF2C were assessed by Alizarin red S staining, calcium assay kit, ALP assay kit, Western blot, immunofluorescence, and quantitative real-time PCR. The interplay between LUM and APOB was estimated using co-immunoprecipitation and immunofluorescence. As a result, β-GP promoted calcification of human VMSCs (HVMSCs) and repressed KIF2C expression. KIF2C overexpression reversed the effect of β-GP on HVSMCs. LUM silencing attenuated β-GP-induced promotion on HVSMC calcification and increased KIF2C expression by interacting with APOB. Collectively, LUM silencing can alleviate β-GP-induced VSMC calcification through mitigating the repression of APOB on KIF2C expression.

Kidney Function and the Use of Vitamin K Antagonists or Direct Oral Anticoagulants in Atrial Fibrillation

Abstract Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and is associated with a five-fold increase in the risk for ischemic stroke. Therefore, lifelong use of anticoagulants is crucial to reduce the morbidity and mortality burden of AF. The incidence of AF in chronic kidney disease (CKD) is two to three times greater than in the general population, and there is a mutual aggravation of the two conditions as well as the presence of both an increased thromboembolic risk in CKD and an increased bleeding risk in severe CKD. The preservation of kidney function in patients with cardiovascular diseases is important, as the latter is the leading cause of death in patients with eGFR <60 mL/min/1.73 m2. Similarly, kidney dysfunction is a serious limitation to the use of many cardiovascular drugs, including anticoagulants. Evidence is present for the faster progression of kidney disease with vitamin K antagonists, likely due to the vitamin K-related process of vascular calcification. Conversely, direct oral anticoagulants (DOACs) have been shown to reduce the progression of CKD and have a beneficial effect as far as the modulation of inflammation and oxidative stress are concerned in experimental models. Another less-discussed problem is the use of DOACs in advanced CKD.

Extracellular vesicles in atherosclerosis and vascular calcification: the versatile non-coding RNAs from endothelial cells and vascular smooth muscle cells.

Atherosclerosis (AS) is characterized by the accumulation of lipids, fibrous elements, and calcification in the innermost layers of arteries. Vascular calcification (VC), the deposition of calcium and phosphate within the arterial wall, is an important characteristic of AS natural history. However, medial arterial calcification (MAC) differs from intimal calcification and cannot simply be explained as the consequence of AS. Endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) are directly involved in AS and VC processes. Understanding the communication between ECs and VSMCs is critical in revealing mechanisms underlying AS and VC. Extracellular vesicles (EVs) are found as intercellular messengers in kinds of physiological processes and pathological progression. Non-coding RNAs (ncRNAs) encapsulated in EVs are involved in AS and VC, including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs). The effects of ncRNAs have not been comprehensively understood, especially encapsulated in EVs. Some ncRNAs have demonstrated significant roles in AS and VC, but it remains unclear the functions of the majority ncRNAs detected in EVs. In this review, we summarize ncRNAs encapsulated in EC-EVs and VSMC-EVs, and the signaling pathways that are involved in AS and VC.

Activity of matrix metalloproteinase type 9 and its relationship with calcification of the thoracic aorta in patients with resistant hypertension: cross-sectional comparative study

Background. The extracellular matrix of vessels is degraded under the influence of matrix metalloproteinases (MMPs). MMP type 9 is of particular interest in arterial hypertension (AH) since its activity is regulated by a tissue inhibitor of matrix metalloproteinase type 1 (TIMP1). The balance of their ratio can shift in either direction depending on the disease stage and provoke vascular wall calcification.
 Objective. This cross-sectional comparative study investigated the level of MMP9 and its type 1 tissue inhibitor and their relationship with the severity of thoracic aorta calcification in patients with resistant hypertension, depending on antihypertensive therapy effectiveness.
 Material and methods. The study included 92 patients with resistant hypertension. All patients underwent 24-hour blood (BP) pressure monitoring (ABPM), and had their index of the thoracic aorta (ТАС) and the plasma levels of MMP9 and TIMP1 assessed.
 Results. Patients were divided into groups based on whether they achieved the BP target level according to the results of ABPM: controlled (n=44) and uncontrolled (n=48) resistant AH. In the second group, most estimated parameters of ABPM were higher, and the variants of the daily BP profile for non-dipper and night-peaker systolic blood pressure (SBP) were more common than in the first group. In the second group, a more pronounced increase in TAC, TIMP1, and TIMP1/MMP9 levels was revealed. Evaluation of the relationship between the studied parameters revealed a positive relationship between TAC and age (r=0.683, p 0.00001), hypertension duration (r=0.610, p 0.00001) and a negative relationship with regular antihypertensive therapy duration (r=0.822, p 0.00001). ТАC was higher in individuals with higher values of SBP (r=0.513, р 0.00001), pulse BP (r=0.805, р 0.00001), rate of morning rise in BP (r=0.678, р 0.00001) and insufficient decrease in SBP at night (r=-0.822, р 0.00001). There was a positive correlation of moderate strength TAC with the level of low-density lipoproteins (r=0.490, p=0.0002), TIMP1 (r=0.344, p=0.005) and the TIMP1/MMP9 ratio (r=0.481, p 0.00001).
 Conclusion. In patients with resistant hypertension, an increase in the TAC was revealed, which has a statistically significant direct correlation with the value of pulse BP, the morning rise in BP, and an insufficient decrease in SBP at night. An imbalance in the TIMP1/MMP9 ratio, rather than an isolated increase in MMP9, can indicate the intensity of the formation and degradation of the extracellular matrix components in patients with resistant AH, which triggers the vascular wall calcification process.

FHL5 Controls Vascular Disease-Associated Gene Programs in Smooth Muscle Cells.

Genome-wide association studies have identified hundreds of loci associated with common vascular diseases, such as coronary artery disease, myocardial infarction, and hypertension. However, the lack of mechanistic insights for many GWAS loci limits their translation into the clinic. Among these loci with unknown functions is UFL1-four-and-a-half LIM (LIN-11, Isl-1, MEC-3) domain 5 (FHL5; chr6q16.1), which reached genome-wide significance in a recent coronary artery disease/ myocardial infarction GWAS meta-analysis. UFL1-FHL5 is also associated with several vascular diseases, consistent with the widespread pleiotropy observed for GWAS loci. We apply a multimodal approach leveraging statistical fine-mapping, epigenomic profiling, and ex vivo analysis of human coronary artery tissues to implicate FHL5 as the top candidate causal gene. We unravel the molecular mechanisms of the cross-phenotype genetic associations through in vitro functional analyses and epigenomic profiling experiments in coronary artery smooth muscle cells. We prioritized FHL5 as the top candidate causal gene at the UFL1-FHL5 locus through expression quantitative trait locus colocalization methods. FHL5 gene expression was enriched in the smooth muscle cells and pericyte population in human artery tissues with coexpression network analyses supporting a functional role in regulating smooth muscle cell contraction. Unexpectedly, under procalcifying conditions, FHL5 overexpression promoted vascular calcification and dysregulated processes related to extracellular matrix organization and calcium handling. Lastly, by mapping FHL5 binding sites and inferring FHL5 target gene function using artery tissue gene regulatory network analyses, we highlight regulatory interactions between FHL5 and downstream coronary artery disease/myocardial infarction loci, such as FOXL1 and FN1 that have roles in vascular remodeling. Taken together, these studies provide mechanistic insights into the pleiotropic genetic associations of UFL1-FHL5. We show that FHL5 mediates vascular disease risk through transcriptional regulation of downstream vascular remodeling gene programs. These transacting mechanisms may explain a portion of the heritable risk for complex vascular diseases.

Association of osteocalcin, osteoprotegerin, and osteopontin with cardiovascular disease and retinopathy in type 2 diabetes.

Novel biomarkers of vascular disease in diabetes could help identify new mechanistic pathways. Osteocalcin, osteoprotegerin, and osteopontin are key molecules involved in bone and vascular calcification processes, both of which are compromised in diabetes. We aimed to evaluate possible associations of osteocalcin, osteoprotegerin, and osteopontin with cardiovascular disease (CVD) and diabetic retinopathy (DR) among people with type 2 diabetes (T2D). Osteocalcin, osteoprotegerin, and osteopontin concentrations were measured at enrolment in 848 participants with T2D from the Sapienza University Mortality and Morbidity Event Rate (SUMMER) Study (ClinicalTrials.gov: NCT02311244). Logistic regression models and propensity score matching were used to assess possible associations of osteocalcin, osteoprotegerin, and osteopontin with a history of CVD and with evidence of any grade of DR adjusting for confounders. Previous CVD was reported in 139 (16.4%) participants, while 144 (17.0%) had DR. After adjusting for possible confounders, osteocalcin but not osteoprotegerin or osteopontin concentrations were associated with a history of CVD (Odds Ratio [OR] and 95% CI for one standard deviation (SD) increase in osteocalcin concentrations (natural log): 1.35 (1.06-1.72), p=0.014). Associations with prevalent DR were seen for osteoprotegerin (OR for one SD increase in osteoprotegerin concentrations (natural log): 1.25 (1.01-1.55), p=0.047) and osteopontin (OR for one SD increase in osteopontin concentrations (natural log): 1.25 (1.02-1.53), p=0.022), but not osteocalcin. In T2D, higher serum osteocalcin concentrations are associated with macrovascular complications and higher osteoprotegerin and osteopontin concentrations with microvascular complications, suggesting that these osteokines might be involved in pathways directly related to vascular disease.

Inflammatory, Metabolic, and Coagulation Effects on Medial Arterial Calcification in Patients with Peripheral Arterial Disease

Calcium deposits in the vessel wall in the form of hydroxyapatite can accumulate in the intimal layer, as in atherosclerotic plaque, but also in the medial layer, as in medial arterial calcification (MAC) or medial Möenckeberg sclerosis. Once considered a passive, degenerative process, MAC has recently been shown to be an active process with a complex but tightly regulated pathophysiology. Atherosclerosis and MAC represent distinct clinical entities that correlate in different ways with conventional cardiovascular risk factors. As both entities coexist in the vast majority of patients, it is difficult to estimate the relative contribution of specific risk factors to their development. MAC is strongly associated with age, diabetes mellitus, and chronic kidney disease. Given the complexity of MAC pathophysiology, it is expected that a variety of different factors and signaling pathways may be involved in the development and progression of the disease. In this article, we focus on metabolic factors, primarily hyperphosphatemia and hyperglycemia, and a wide range of possible mechanisms by which they might contribute to the development and progression of MAC. In addition, we provide insight into possible mechanisms by which inflammatory and coagulation factors are involved in vascular calcification processes. A better understanding of the complexity of MAC and the mechanisms involved in its development is essential for the development of potential preventive and therapeutic strategies.

Inactive Matrix Gla Protein in Relation to Renal and Cardiac Functions and Cardiac Valvular Calcification Among Type 2 Diabetes Patients.

Matrix Gla protein (MGP) is a robust innate suppressor of the detrimental process of vascular calcification in the human body. The interrelationship between circulating MGP levels and renal and cardiac dysfunction, besides echocardiographic calcification score (ECS) was investigated in a sample of type 2 diabetes (T2D) patients. The study included 130 subjects. They were 95 patients with T2D and 35 age- and sex-matched healthy controls. Patients were further subdivided into 52 T2D patients without DKD (eGFR ⩾ 60 ml/minute/1.73 m²) and 43 T2D persons with DKD (eGFR > 60 ml/minute/1.73 m²). Serum MGP levels, determined by ELISA, renal function tests, lipid profile, and echocardiography were studied in all participants. Significantly elevated circulating inactive MGP level was noted in individuals having T2D compared to controls. It correlated negatively with eGFR and left ventricular (LV) diastolic and systolic functions and positively with indices of LV hypertrophy. ECS was significantly increased in both T2D groups compared to controls and in DKD group compared to the diabetic group without DKD. A significant positive correlation was observed between inactive MGP and ECS. Serum inactive MGP may contribute to the development of DKD and to the associated process of cardiac valvular calcification. It may be a beneficial diagnostic marker for early prediction of cardiac calcification and preclinical LV systolic and diastolic dysfunction in T2D patients, especially in those complicated with DKD.

Interleukin-29 Accelerates Vascular Calcification via JAK2/STAT3/BMP2 Signaling.

Background Vascular calcification (VC), associated with enhanced cardiovascular morbidity and mortality, is characterized by the osteogenic transdifferentiation of vascular smooth muscle cells. Inflammation promotes VC initiation and progression. Interleukin (IL)-29, a newly discovered member of type III interferon, has recently been implicated in the pathogenesis of autoimmune diseases. Here we evaluated the role of IL-29 in the VC process and underlying inflammatory mechanisms. Methods and Results The mRNA expression of IL-29 was significantly increased and positively associated with an increase in BMP2 (bone morphogenetic protein 2) mRNA level in calcified carotid arteries from patients with coronary artery disease or chronic kidney disease. IL-29 and BMP2 proteins are colocalized in human calcified arteries. IL-29 binding to its specific receptor IL-28Rα (IL-28 receptor α) (IL-29/IL-28Rα) inhibited the proliferation of rat vascular smooth muscle cellswithout altering cell apoptosis or migration. IL-29 promoted the calcification of rat vascular smooth muscle cellsand their osteogenic transdifferentiation in vitro as well as the rat aortic ring calcification ex vivo, induced by the calcification medium or osteogenic medium. The procalcification effect of IL-29 was reduced by pharmacological inhibition of IL-29/IL-28Rα binding as well as suppression of janus kinase 2/signal transducer and activator of transcription pathway activation, accompanied by decreased BMP2 expression in the cultured rat vascular smooth muscle cells. Conclusions These results suggest an important role of IL-29 in VC development, at least partly, via activating the janus kinase 2/signal transducer and activator of transcription 3 signaling. Inhibition of IL-29 or its specific receptor, IL-28Rα, may provide a novel strategy to reduce VC in patients with vascular diseases.

Panax notoginseng Suppresses Bone Morphogenetic Protein-2 Expression in EA.hy926 Endothelial Cells by Inhibiting the Noncanonical NF-κB and Wnt/β-Catenin Signaling Pathways

Panax notoginseng (PN) exerts cardiovascular-disease-protective effects, but the effect of PN on reducing vascular calcification (VC) is unknown. Under the VC process, however, endothelial bone morphogenetic protein-2 (BMP-2) signals connect endothelial and smooth muscle cells. To investigate the effects of PN water extract (PNWE) on BMP-2 expression, human EA.hy926 endothelial cells were pretreated with PNWE for 48 h, and BMP-2 expression was then induced using warfarin/β-glycerophosphate (W/BGP) for another 24 h. The expression of BMP-2, the degrees of oxidative stress and inflammation, and the activation of noncanonical NF-κB and Wnt/β-catenin signaling were analyzed. The results showed that the BMP-2 levels in EA.hy926 cells were reduced in the groups treated with 10, 50, or 100 μg/mL PNWE combined with W/BGP. PNWE combined with W/BGP significantly reduced thiobarbituric-acid-reactive substrate and reactive oxygen species levels as well as prostaglandin E2, IL-1β, IL-6, and TNF-α. PNWE (10, 50, and 100 μg/mL) reduced the p52 levels and p52/p100 protein ratio. Wnt and β-catenin protein expression was decreased in the groups treated with PNWE combined with W/BGP. These results showed that PNWE reduced BMP-2 expression in EA.hy926 cells by inhibiting the noncanonical NF-κB and Wnt/β-catenin signaling pathways.

The mechanosensitive Piezo1 channels contribute to the arterial medial calcification.

Vascular calcification (VC) is associated with a number of cardiovascular diseases, as well as chronic kidney disease. The role of smooth muscle cells (SMC) has already been widely explored in VC, as has the role of intracellular Ca2+ in regulating SMC function. Increased intracellular calcium concentration ([Ca2+]i) in vascular SMC has been proposed to stimulate VC. However, the contribution of the non-selective Piezo1 mechanosensitive cation channels to the elevation of [Ca2+]i, and consequently to the process of VC has never been examined. In this work the essential contribution of Piezo1 channels to arterial medial calcification is demonstrated. The presence of Piezo1 was proved on human aortic smooth muscle samples using immunohistochemistry. Quantitative PCR and Western blot analysis confirmed the expression of the channel on the human aortic smooth muscle cell line (HAoSMC). Functional measurements were done on HAoSMC under control and calcifying condition. Calcification was induced by supplementing the growth medium with inorganic phosphate (1.5mmol/L, pH 7.4) and calcium (CaCl2, 0.6mmol/L) for 7days. Measurement of [Ca2+]i using fluorescent Fura-2 dye upon stimulation of Piezo1 channels (either by hypoosmolarity, or Yoda1) demonstrated significantly higher calcium transients in calcified as compared to control HAoSMCs. The expression of mechanosensitive Piezo1 channel is augmented in calcified arterial SMCs leading to a higher calcium influx upon stimulation. Activation of the channel by Yoda1 (10μmol/L) enhanced calcification of HAoSMCs, while Dooku1, which antagonizes the effect of Yoda1, reduced this amplification. Application of Dooku1 alone inhibited the calcification. Knockdown of Piezo1 by siRNA suppressed the calcification evoked by Yoda1 under calcifying conditions. Our results demonstrate the pivotal role of Piezo1 channels in arterial medial calcification.

Exosomes derived from bone marrow mesenchymal stem cells inhibit human aortic vascular smooth muscle cells calcification via the miR-15a/15b/16/NFATc3/OCN axis

Cardiovascular events among patients with chronic kidney disease (CKD) are associated with vascular calcification (VC). Nevertheless, the process of vascular calcification is complicated. A mechanism of VC is cellular osteogenic transdifferentiation. The mechanism through which bone marrow mesenchymal stem cell-derived exosomes (BMSC-Exo) relieve VC is unknown. For the purpose of this study, we used human aortic vascular smooth muscle cells (HA-VSMCs) stimulated by high phosphate to investigate how BMSC-Exo works. Cell calcification was detected by Alizarin red S staining, AKP activity analysis, and the Ca2+ concentration test. The dual-luciferase reporter gene assays were utilized to confirm the targeting link between miR-15a-5p, miR-15b-5p, and miR-16-5p (miR-15a/15b/16) and nuclear factors of activated T cells 3 (NFATc3). The expression of osteogenic transdifferentiation biomarkers was detected using Western blot and RT-qPCR. Based on our findings, miR-15a/15b/16 plays a crucial role in BMSC-Exo's inhibitory effects on calcification and osteogenic transdifferentiation. We then confirmed that miR-15a/15b/16 specifically target the 3′UTR of NFATc3 mRNA and that three miRNAs are more effective than one miRNA. Moreover, we found that down-regulation of NFATc3 could inhibit osteocalcin (OCN) expression, thereby inhibiting the osteogenic transdifferentiation and calcification of HA-VSMCs. This study found that BMSC-Exo plays a role in calcification inhibition by transferring miR-15a/15b/16 and inhibiting their common target gene NFATc3, which down-regulates OCN expression and thus inhibits HA-VSMC osteogenic transdifferentiation. This study identifies a novel target for therapeutic therapy of CKD-VC.

The Risk of the Development and Relationship of Kidney Stone Disease and Osteoporosis (Literature review)

Urinary stone disease (USD) is a common pathology with the formation of calculi in the kidneys, ureter, and bladder. Besides the family history, hyperparathyroidism, hypo- and hypervitaminosis of vitamin D, hypercalciuria, and hyperoxaluria are the high risk factors for USD development. This is due primarily to the activation of bone resorption with increased hypercalciuria. It is known that in the urine of every person there is a small amount of urea, inorganic salts, uric acid, creatinine and other substances. The main reason for the formation of calculi is a certain metabolic disorder, which leads to the formation of insoluble salts from which stones are formed – urates, phosphates, oxalates, etc. One of the unsolved problems in the metaphylaxis of USD is the treatment and prevention of osteoporosis which is comorbid with it, since calcium and vitamin D preparations are widely used for the prevention and treatment of osteoporosis. Osteoporosis and arterial calcification often coincide in the nature of the manifestation, which indicates an imbalance in the redistribution of calcium with a predominant direction in the vascular the wall. Vitamin K2 deficiency is closely related to the process of vascular calcification. In the cardiovascular system, with the use of vitamin K antagonists or vitamin K deficiency, calcification of the endothelium of blood vessels occurs. The effect of osteocalcin protein on stone formation processes is controversial. For example, some researchers have found that high serum level of Glaprotein is associated with a lower risk of kidney stones. Based on the results of a daily urinalysis study, the EAU Guidelines (2022) updated the recommendations on metaphylactic USD regarding the benefit/harm of additional calcium and vitamin D use in patients with nephrolithiasis depending on the type of crystalluria. The absence of recommendations for the management of patients with combined pathologies (USD, osteoporosis, cardiovascular diseases) prompts a comprehensive assessment of common risk factors, as well as the formation of programs and algorithms for early diagnosis and the development of recommendations for the prevention and avoidance of complications. Based on the literature analysis, it was established that today the issue of choosing the optimal management for diagnosis and treatment of USD and osteoporosis is still very controversial and ambiguous. There is a necessity for detailed study of this problem, the development of a complex differentiated approach to diagnosis and treatment of patients.

Iron overload impairs renal function and is associated with vascular calcification in rat aorta

Vascular calcification (VC) has been associated with a risk of cardiovascular diseases. Iron may play a critical role in progressive VC. Therefore, we investigated the effects of iron overload on the aorta of rats. A rat model of iron overload was established by intraperitoneal injection of Iron-Dextran. The levels of iron, calcium, and ALP activity were detected. Von Kossa staining and Perl’s staining were conducted. The expression of iron metabolism-related and calcification related factors were examined in the aortic tissue of rats. The results showed serum and aortic tissue iron were increased induced by iron overload and excessive iron induced hepatic and renal damage. In iron overload rats, the expression of divalent metal transporter 1 (DMT1) and hepcidin were higher, but ferroportin1 (FPN1) was lower. Von Kossa staining demonstrated calcium deposition in the aorta of iron overload rats. The calcium content and ALP activity in serum and aortic tissue were increased and iron level in aortic tissue highly correlated with calcium content and ALP activity. The expressions of the osteogenic markers were increased while a decrease of Alpha-smooth muscle actin (α-SMA) in the aortic tissue of iron overload rats. IL-24 was increased during the calcification process induced by iron. Overall, we demonstrated excessive iron accumulation in the aortic tissue and induced organs damage. The iron metabolism-related factors were significantly changed during iron overload. Moreover, we found that iron overload leads to calcium deposition in aorta, playing a key role in the pathological process of VC by mediating osteoblast differentiation factors.