Antibiotic-induced gut microbiota disruption promotes vascular calcification by reducing short-chain fatty acid acetate.

BACKGROUND: Vascular calcification is a common vascular lesion associated with high morbidity and mortality from cardiovascular events. Antibiotics can disrupt the gut microbiota (GM) and have been shown to exacerbate or attenuate several human diseases. However, whether antibiotic-induced GM disruption affects vascular calcification remains unclear. METHODS: Antibiotic cocktail (ABX) treatment was utilized to test the potential effects of antibiotics on vascular calcification. The effects of antibiotics on GM and serum short-chain fatty acids (SCFAs) in vascular calcification mice were analyzed using 16 S rRNA gene sequencing and targeted metabolomics, respectively. Further, the effects of acetate, propionate and butyrate on vascular calcification were evaluated. Finally, the potential mechanism by which acetate inhibits osteogenic transformation of VSMCs was explored by proteomics. RESULTS: ABX and vancomycin exacerbated vascular calcification. 16 S rRNA gene sequencing and targeted metabolomics analyses showed that ABX and vancomycin treatments resulted in decreased abundance of Bacteroidetes in the fecal microbiota of the mice and decreased serum levels of SCFAs. In addition, supplementation with acetate was found to reduce calcium salt deposition in the aorta of mice and inhibit osteogenic transformation in VSMCs. Finally, using proteomics, we found that the inhibition of osteogenic transformation of VSMCs by acetate may be related to glutathione metabolism and ubiquitin-mediated proteolysis. After adding the glutathione inhibitor Buthionine sulfoximine (BSO) and the ubiquitination inhibitor MG132, we found that the inhibitory effect of acetate on VSMC osteogenic differentiation was weakened by the intervention of BSO, but MG132 had no effect. CONCLUSION: ABX exacerbates vascular calcification, possibly by depleting the abundance of Bacteroidetes and SCFAs in the intestine. Supplementation with acetate has the potential to alleviate vascular calcification, which may be an important target for future treatment of vascular calcification.

Rivaroxaban versus vitamin K antagonist treatment on the progression of coronary calcification: the IRIVASC-trial.

Vitamin K antagonists (VKA) remain the only option of anticoagulation for people with mechanical valve replacement and due to their wider availability and lower acquisition costs, VKA's remain widely used in low- and middle-income countries. It has been suggested that prolonged use of VKAs can increase the development of vascular and valvular calcification, though this effect has not been examined in larger randomized prospective trials. This investigator-initiated multicenter, prospective, randomized, open-label interventional trial randomized patients with baseline coronary or valvular calcification and an indication for prolonged oral anticoagulation therapy to Marcumar or Rivaroxaban. Patients were followed-up through repeat coronary computed tomographies to measure the progression of coronary and valvular calcification for up to 24 months. 192 patients were randomized between 2013 and 2018 to receive either Rivaroxaban or Marcumar and followed for up to 24 months. Coronary calcification significantly increased over time although there was no significant difference in progression between the groups after 12 and 24 months as measured by the Agatston score [360.7 (90.2; 1075.3) vs 380.4 (136.4; 1546.9) p = 0.69], the volume score [295.8 (93.0; 995.3) vs 335.5 (128.7; 1316.9) p = 0.95] and the mass score [58.5 (15.9; 172.0) vs 71.1 (24.8; 257.3) p = 0.5]. Dephosphorylated, uncarboxylated matrix Gla Protein (Dp-ucMGP) significantly decreased in the VKA group [Δ dp-uc MGP - 95.2 (- 554.1; 156.0) vs 231.3 (- 59.7; 388.1) p < 0.001]. There does not appear to be a relevant effect of vitamin K inhibition by the vitamin K antagonist marcumar upon coronary calcification.

Target analysis and identification of curcumin against vascular calcification.

To investigate the mechanism of curcumin (CUR) on vascular calcification (VC), we screen for common targets of CUR and atherosclerosis and verify the targets genes in vivo and in vitro experiments. The common targets of CUR and AS were screened and obtained using different databases. These target genes were analyzed by GO and KEGG pathway enrichment analysis. PPI network analysis was performed and to analyze the key targets. A rat VC model was constructed and CUR was fed for three weeks. The changes of vascular structure and calcium salt deposition were observed in H&E and Von Kossa staining. Further, the expression of these target proteins was detected in the primary VSMCs of VC. The 31 common targets were obtained. GO functional enrichment analysis obtained 1284 terms and KEGG pathway enriched 66 pathways. The key genes were identified in the cytoHubba plugin. The molecular docking analysis showed that CUR bound strongly to EGFR, STAT3 and BCL2. The animal experiments showed the deposition calcium salt reduced by the CUR administration. These proteins BMP2, RUNX2, EGFR, STAT3 and BAX expression were upregulated in VC group and CUR attenuated the upregulated expression. The signal protein Akt and p65 expression increased in VC group and decreased in CUR group. We identified some common target genes of CUR and AS and identified these key genes. The anti-VC effect of CUR was associated with the inhibition of upregulation of EGFR, STAT3 and RUNX2 expression in VSMCs.

STING1-accelerated vascular smooth muscle cell senescence-associated vascular calcification in diabetes is ameliorated by oleoylethanolamide via improved mitochondrial DNA oxidative damage.

Vascular calcification is a prevalent hallmark of cardiovascular risk in elderly and diabetic individuals. Senescent vascular smooth muscle cells (VSMCs) participate in calcification; however, the associated underlying mechanisms remain unknown. Aberrant activation of the cytosolic DNA sensing adaptor stimulator of interferon gene 1 (STING1) caused by cytosolic DNA, particularly that leaked from damaged mitochondria, is a catalyst for aging-related diseases. Although oleoylethanolamide (OEA) is an endogenous bioactive lipid mediator with lipid overload-associated vasoprotective effects, its benefit in diabetic vascular calcification remains uncharacterized. This study focused on the role of STING1 in mitochondrial dysfunction-mediated calcification and premature VMSC senescence in diabetes and the effects of OEA on these pathological processes. In diabetic in vivo rat/mouse aorta calcification models and an in vitro VSMC calcification model induced by Nε-carboxymethyl-lysine (CML), senescence levels, STING1 signaling activation, and mitochondrial damage markers were significantly augmented; however, these alterations were markedly alleviated by OEA, partially in a nuclear factor erythroid 2-related factor 2 (Nrf2)-dependent manner, and similar anti-calcification and senescence effects were observed in STING1-knockout mice and STING1-knockdown VSMCs. Mechanistically, mitochondrial DNA (mtDNA) damage was aggravated by CML in a reactive oxygen species-dependent manner, followed by mtDNA leakage into the cytosol, contributing to VSMC senescence-associated calcification via STING1 pathway activation. OEA treatment significantly attenuated the aforementioned cytotoxic effects of CML by enhancing cellular antioxidant capacity through the maintenance of Nrf2 translocation to the nucleus. Collectively, targeting STING1, a newly defined VSMC senescence regulator, contributes to anti-vascular calcification effects.

Non-nitrogen-containing bisphosphonates and nitrogen-containing bisphosphonates for the treatment of atherosclerosis and vascular calcification: A meta-analysis.

BACKGROUND: The role of non-nitrogen-containing bisphosphonates (non-N-BPs) and nitrogen-containing bisphosphonates (N-BPs) in the treatment of atherosclerosis (AS) and vascular calcification (VC) is uncertain. This meta-analysis was conducted to evaluate the efficacy of non-N-BPs and N-BPs in the treatment of AS and VC. METHODS: The PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, and Wanfang databases were searched from their inception to July 5th, 2023. Eligible studies comparing bisphosphonates (BPs) versus no BPs in the treatment of AS and VC were included. The data were analyzed using Review Manager Version 5.3. RESULTS: Seventeen studies were included in this meta-analysis. Twelve were randomized control trials (RCTs), and 5 were nonrandomized studies. Overall, 813 patients were included in the BPs group, and 821 patients were included in the no BPs group. Compared with no BP treatment, non-N-BP or N-BP treatment did not affect serum calcium (P > .05), phosphorus (P > .05) or parathyroid hormone (PTH) levels (P > .05). Regarding the effect on serum lipids, non-N-BPs decreased the serum total cholesterol (TC) level (P < .05) and increased the serum triglyceride (TG) level (P < .01) but did not affect the serum low-density lipoprotein cholesterol (LDL-C) level (P > .05). N-BPs did not affect serum TC (P > .05), TG (P > .05) or LDL-C levels (P > .05). Regarding the effect on AS, non-N-BPs did not have a beneficial effect (P > .05). N-BPs had a beneficial effect on AS, including reducing the intima-media thickness (IMT) (P < .05) and plaque area (P < .01). For the effect on VC, non-N-BPs had a beneficial effect (P < .01), but N-BPs did not have a beneficial effect (P > .05). CONCLUSION: Non-N-BPs and N-BPs did not affect serum calcium, phosphorus or PTH levels. Non-N-BPs decreased serum TC levels and increased serum TG levels. N-BPs did not affect serum lipid levels. Non-N-BPs had a beneficial effect on VC, and N-BPs had a beneficial effect on AS.

Mitochondria-Targeted Natural Antioxidant Nanosystem for Diabetic Vascular Calcification Therapy.

The development of nanotherapy targeting mitochondria to alleviate oxidative stress is a critical therapeutic strategy for vascular calcification (VC) in diabetes. In this study, we engineered mitochondria-targeted nanodrugs (T4O@TPP/PEG-PLGA) utilizing terpinen-4-ol (T4O) as a natural antioxidant and mitochondrial protector, PEG-PLGA as the nanocarrier, and triphenylphosphine (TPP) as the mitochondrial targeting ligand. In vitro assessments demonstrated enhanced cellular uptake of T4O@TPP/PEG-PLGA, with effective mitochondrial targeting. This nanodrug successfully reduced oxidative stress induced by high glucose levels in vascular smooth muscle cells. In vivo studies showed prolonged retention of the nanomaterials in the thoracic aorta for up to 24 h. Importantly, experiments in diabetic VC models underscored the potent antioxidant properties of T4O@TPP/PEG-PLGA, as evidenced by its ability to mitigate VC and restore mitochondrial morphology. These results suggest that these nanodrugs could be a promising strategy for managing diabetic VC.

Overexpression of miR-204-5p Alleviates Osteogenic Differentiation and Calcification of Human Aortic Vascular Smooth Muscle Cells by Targeting Calcium/Calmodulin-dependent Protein Kinase 1.

ABSTRACT: Vascular calcification (VC), a major complication in chronic kidney disease (CKD), is predominantly driven by osteoblastic differentiation. Recent studies have highlighted the crucial role of microRNAs in CKD's pathogenesis. Here, our research focused on the effects of miR-204-5p and its molecular mechanisms within VC. We initially found a notable decrease in miR-204-5p levels in human aortic vascular smooth muscle cells stimulated with inorganic phosphate, using this as a VC model in vitro. Following the overexpression of miR-204-5p, a decrease in VC was observed, as indicated by alizarin red S staining and measurements of calcium content. This decrease was accompanied by lower levels of the osteogenic marker, runt-related transcription factor 2, and higher levels of α-smooth muscle actin, a marker of contractility. Further investigation showed that calcium/calmodulin-dependent protein kinase 1 (CAMK1), which is a predicted target of miR-204-5p, promotes VC. Conversely, overexpressing miR-204-5p reduced VC by suppressing CAMK1 activity. Overexpressing miR-204-5p also effectively mitigated aortic calcification in an in vivo rat model. In summary, our research indicated that targeting the miR-204-5p/CAMK1 pathway could be a viable strategy for mitigating VC in CKD patients.

Sodium-glucose cotransporter 2 inhibitors attenuate vascular calcification by suppressing endoplasmic reticulum protein thioredoxin domain containing 5 dependent osteogenic reprogramming.

AIMS: Vascular calcification is strongly linked to the development of major adverse cardiovascular events, but effective treatments are lacking. Sodium-glucose cotransporter 2 (SGLT2) inhibitors are an emerging category of oral hypoglycemic drugs that have displayed marked effects on metabolic and cardiovascular diseases, including recently reported vascular medial calcification. However, the roles and underlying mechanisms of SGLT2 inhibitors in vascular calcification have not been fully elucidated. Thus, we aimed to further determine whether SGLT2 inhibitors protect against vascular calcification and to investigate the mechanisms involved. METHODS AND RESULTS: A computed tomography angiography investigation of coronary arteries from 1554 patients with type 2 diabetes revealed that SGLT2 inhibitor use was correlated with a lower Agatston calcification score. In the vitamin D3 overdose, 5/6 nephrectomy chronic kidney disease-induced medial calcification and Western diet-induced atherosclerotic intimal calcification models, dapagliflozin (DAPA) substantially alleviated vascular calcification in the aorta. Furthermore, we showed that DAPA reduced vascular calcification via Runx2-dependent osteogenic transdifferentiation in vascular smooth muscle cells (VSMCs). Transcriptome profiling revealed that thioredoxin domain containing 5 (TXNDC5) was involved in the attenuation of vascular calcification by DAPA. Rescue experiments showed that DAPA-induced TXNDC5 downregulation in VSMCs blocked the protective effect on vascular calcification. Furthermore, TXNDC5 downregulation disrupted protein folding-dependent Runx2 stability and promoted subsequent proteasomal degradation. Moreover, DAPA downregulated TXNDC5 expression via amelioration of oxidative stress and ATF6-dependent endoplasmic reticulum stress. Consistently, the class effects of SGLT2 inhibitors on vascular calcification were validated with empagliflozin in intimal and medial calcification models. CONCLUSIONS: SGLT2 inhibitors ameliorate vascular calcification through blocking endoplasmic reticulum stress-dependent TXNDC5 upregulation and promoting subsequent Runx2 proteasomal degradation, suggesting that SGLT2 inhibitors are potentially beneficial for vascular calcification treatment and prevention.

Effects of Empagliflozin on Vascular and Skeletal Mineralization in Hyperlipidemic Mice.

Cardiovascular disease and osteoporosis, major causes of morbidity and mortality, are associated with hyperlipidemia. Recent studies show that empagliflozin (EMPA), an inhibitor of sodium-glucose cotransporter-2 (SGLT2), improves cardiovascular health. In preclinical animal studies, EMPA mitigates vascular calcification in the males but its effects in the females are not known. Thus, we used female mice to test the effects of EMPA on calcification in the artery wall, cardiac function, and skeletal bone. By serial in vivo microCT imaging, we followed the progression of aortic calcification and bone mineral density in young and older female Apoe-/- mice fed a high-fat diet with or without EMPA. The two different age groups were used to compare early vs. advanced stages of aortic calcification. Results show that EMPA treatment increased urine glucose levels. Aortic calcium content increased in both the controls and the EMPA-treated mice, and EMPA did not affect progression of aortic calcium content in both young and older mice. However, 3-D segmentation analysis of aortic calcium deposits on microCT images revealed that EMPA-treated mice had significantly less surface area and volume of calcified deposits as well as fewer numbers of deposits than the control mice. To test for direct effects on vascular cell calcification, we treated murine aortic smooth muscle cells with EMPA, and results showed a slight inhibition of alkaline phosphatase activity and inflammatory matrix calcification. As for skeletal bone, EMPA-treated mice had significantly lower BMD than the controls in both the lumbar vertebrae and femoral bones in both young and older mice. The findings suggest that, in hyperlipidemic female mice, unlike males, SGLT2 inhibition with empagliflozin does not mitigate progression of aortic calcification and may even lower skeletal bone density.

Glucagon-like peptide-1 receptor agonist exendin 4 ameliorates diabetes-associated vascular calcification by regulating mitophagy through the AMPK signaling pathway.

BACKGROUND: Vascular calcification (VC) is a complication in diabetes mellitus (DM) patients. Osteogenic phenotype switching of vascular smooth muscle cells (VSMCs) plays a critical role in diabetes-related VC. Mitophagy can inhibit phenotype switching in VSMCs. This study aimed to investigate the role of the glucagon-like peptide-1 receptor (GLP-1R) agonist exendin 4 (EX4) in mitophagy-induced phenotype switching. MATERIALS AND METHODS: The status of VC in T2DM mice was monitored using Von Kossa and Alizarin Red S (ARS) staining in mouse aortic tissue. Human aortic smooth muscle cells were cultured in high glucose (HG) and ß-glycerophosphate (ß-GP) conditioned medium. Accumulation of LC3B and p62 was detected in the mitochondrial fraction. The effect of EX4 in vitro and in vivo was investigated by knocking down AMPKα1. RESULTS: In diabetic VC mice, EX4 decreased the percentage of von Kossa/ARS positive area. EX4 inhibited osteogenic differentiation of HG/ß-GP-induced VSMCs. In HG/ß-GP-induced VSMCs, the number of mitophagosomes was increased, whereas the addition of EX4 restored mitochondrial function, increased the number of mitophagosome-lysosome fusions, and reduced p62 in mitochondrial frictions. EX4 increased the phosphorylation of AMPKα (Thr172) and ULK1 (Ser555) in HG/ß-GP-induced VSMCs. After knockdown of AMPKα1, ULK1 could not be activated by EX4. The accumulation of LC3B and p62 could not be reduced after AMPKα1 knockdown. Knockdown of AMPKα1 negated the therapeutic effects of EX4 on VC of diabetic mice. CONCLUSION: EX4 could promote mitophagy by activating the AMPK signaling pathway, attenuate insufficient mitophagy, and thus inhibit the osteogenic phenotype switching of VSMCs.

Inhibition of vascular calcification by Compound Danshen Dripping Pill through multiple mechanisms.

BACKGROUND: Vascular calcification refers to the abnormal accumulation of calcium in the walls of blood vessels and is a risk factor often overlooked in cardiovascular disease. However, there is currently no specific drug for treating vascular calcification. Compound Danshen Dripping Pill (CDDP) is widely used to treat cardiovascular diseases, but its effect on vascular calcification has not been reported. PURPOSE: We investigated the effects of CDDP on vascular calcification in ApoE-/- mice and in vitro and elucidated its mechanism of action. STUDY DESIGN: Firstly, we found that CDDP has the potential to improve calcification based on network pharmacology analysis. Then, we performed the following experiments: in vivo, ApoE-/- mice were fed a high-fat diet randomly supplemented with CDDP for 16 weeks. Atherosclerosis and vascular calcification were determined. In vitro, human aortic smooth muscle cells (HASMCs), human umbilical vein endothelial cells (HUVECs), and human aortic endothelial cells (HAECs) were used to determine the mechanisms for CDDP-inhibited vascular calcification. RESULTS: In this study, we observed that CDDP reduced intimal calcification in atherosclerotic lesions of ApoE-deficient mice fed a high-fat diet, as well as the calcification in cultured SMCs and ECs. Mechanistically, CDDP inhibited the Wnt/ß-catenin pathway by up-regulating the expression of DKK1 and LRP6, which are upstream inhibitors of Wnt, leading to a reduction in the expression of osteoblastic transition markers (ALP, OPN, BMP2, and RUNX2). Furthermore, CDDP enhanced the secretion of DKK1, which plays a role in mediating EC-SMC crosstalk in calcification. Additionally, VC contributes to vascular aging by inhibiting Sirt1 and increasing senescence parameters (SA-ß-gal, p21, and p16). However, CDDP reversed these changes by activating Sirt1. CDDP also reduced the levels of pro-inflammatory cytokines and the senescence-associated secretory phenotype in vivo and in vitro. CONCLUSIONS: Our study suggests that CDDP reduces vascular calcification by regulating the DKK1/LRP6/ß-catenin signaling pathway in ECs/SMCs and interactions with the crosstalk of ECs and SMCs. It also reduces the senescence of ECs/SMCs, contributing to the Sirt1 activation, indicating CDDP's novel role in ameliorating vascular calcification.

Pilot study to evaluate the safety and effectiveness of etidronate treatment for arterial calcification due to deficiency of CD73 (ACDC).

BACKGROUND: Arterial calcification due to deficiency of CD73 (ACDC; OMIM 211800) is a rare genetic disease resulting in calcium deposits in arteries and small joints causing claudication, resting pain, severe joint pain, and deformities. Currently, there are no standard treatments for ACDC. Our previous work identified etidronate as a potential targeted ACDC treatment, using in vitro and in vivo disease models with patient-derived cells. In this study, we test the safety and effectiveness of etidronate in attenuating the progression of lower-extremity arterial calcification and vascular blood flow based on the computed tomography (CT) calcium score and ankle-brachial index (ABI). METHODS: Seven adult patients with a confirmed genetic diagnosis of ACDC were enrolled in an open-label, nonrandomized, single-arm pilot study for etidronate treatment. They took etidronate daily for 14 days every 3 months and were examined at the NIH Clinical Center bi-annually for 3 years. They received a baseline evaluation as well as yearly follow up after treatment. Study visits included imaging studies, exercise tolerance tests with ABIs, clinical blood and urine testing, and full dental exams. RESULTS: Etidronate treatment appeared to have slowed the progression of further vascular calcification in lower extremities as measured by CT but did not have an effect in reversing vascular and/or periarticular joint calcifications in our small ACDC cohort. CONCLUSIONS: Etidronate was found to be safe and well tolerated by our patients and, despite the small sample size, appeared to show an effect in slowing the progression of calcification in our ACDC patient cohort.(ClinicalTrials.gov Identifier NCT01585402).

Empagliflozin ameliorates vascular calcification in diabetic mice through inhibiting Bhlhe40-dependent NLRP3 inflammasome activation.

Type 2 diabetes mellitus (T2DM) patients exhibit greater susceptibility to vascular calcification (VC), which has a higher risk of death and disability. However, there is no specific drug for VC therapy. NLRP3 inflammasome activation as a hallmark event of medial calcification leads to arterial stiffness, causing vasoconstrictive dysfunction in T2DM. Empagliflozin (EMPA), a sodium-glucose co-transporter 2 inhibitor (SGLT2i), restrains hyperglycemia with definite cardiovascular benefits. Given the anti-inflammatory activity of EMPA, herein we investigated whether EMPA protected against VC in the aorta of T2DM mice by inhibiting NLRP3 inflammasome activation. Since db/db mice receiving a normal diet developed VC at the age of about 20 weeks, we administered EMPA (5, 10, 20 mg·kg-1·d-1, i.g) to 8 week-old db/db mice for 12 weeks. We showed that EMPA intervention dose-dependently ameliorated the calcium deposition, accompanied by reduced expression of RUNX2 and BMP2 proteins in the aortas. We found that EMPA (10 mg·kg-1·d-1 for 6 weeks) also protected against VC in vitamin D3-overloaded mice, suggesting the protective effects independent of metabolism. We showed that EMPA (10 mg·kg-1·d-1) inhibited the abnormal activation of NLRP3 inflammasome in aortic smooth muscle layer of db/db mice. Knockout (KO) of NLRP3 significantly alleviated VC in STZ-induced diabetic mice. The protective effects of EMPA were verified in high glucose (HG)-treated mouse aortic smooth muscle cells (MOVASs). In HG-treated NLRP3 KO MOVASs, EMPA (1 µM) did not cause further improvement. Bioinformatics and Western blot analysis revealed that EMPA significantly increased the expression levels of basic helix-loop-helix family transcription factor e40 (Bhlhe40) in HG-treated MOVASs, which served as a negative transcription factor directly binding to the promotor of Nlrp3. We conclude that EMPA ameliorates VC by inhibiting Bhlhe40-dpendent NLRP3 inflammasome activation. These results might provide potential significance for EMPA in VC therapy of T2DM patients.

Comparative efficacy of sodium thiosulfate, bisphosphonates, and cinacalcet for the treatment of vascular calcification in patients with haemodialysis: a systematic review and network meta-analysis.

BACKGROUND: Up to now, there is no unequivocal intervention to mitigate vascular calcification (VC) in patients with hemodialysis. This network meta-analysis aimed to systematically evaluate the clinical efficacy of sodium thiosulfate, bisphosphonates, and cinacalcet in treating vascular calcification. METHODS: A comprehensive study search was performed using PubMed, Web of Science, the Cochrane Library, EMBASE and China National Knowledge Internet (CNKI) to collect randomized controlled trials (RCTs) of sodium thiosulfate, bisphosphonates, and cinacalcet for vascular calcification among hemodialysis patients. Then, network meta-analysis was conducted using Stata 17.0 software. RESULTS: In total, eleven RCTs including 1083 patients were qualified for this meta-analysis. We found that cinacalcet (SMD - 0.59; 95% CI [-0.95, -0.24]) had significant benefit on vascular calcification compared with conventional therapy, while sodium thiosulfate or bisphosphonates did not show such efficiency. Furthermore, as for ranking the efficacy assessment, cinacalcet possessed the highest surface under the cumulative ranking curve (SUCRA) value (88.5%) of lessening vascular calcification and was superior to sodium thiosulfate (50.4%) and bisphosphonates (55.4%). Thus, above results suggested that cinacalcet might be the most promising drug for vascular calcification treatment in hemodialysis patients. Mechanistically, our findings illustrated that cinacalcet reduced serum calcium (SMD - 1.20; 95% CI [-2.08, - 0.33]) and showed the tendency in maintaining the balance of intact Parathyroid Hormone (iPTH) level. CONCLUSIONS: This network meta-analysis indicated that cinacalcet appear to be more effective than sodium thiosulfate and bisphosphonates in mitigating vascular calcification through decreasing serum calcium and iPTH. And cinacalcet might be a reasonable option for hemodialysis patients with VC in clinical practice. SYSTEMATIC REVIEW REGISTRATION: [ http://www.crd.york.ac.uk/PROSPERO ], identifier [CRD42022379965].

Phosphonoformic acid reduces hyperphosphatemia-induced vascular calcification via Pit-1.

OBJECTIVE: This study aimed to examine the mechanism of hyperphosphatemia-induced vascular calcification (HPVC). METHODS: Primary human aortic smooth muscle cells and rat aortic rings were cultured in Dulbecco's modified Eagle's medium supplemented with 0.9 mM or 2.5 mM phosphorus concentrations. Type III sodium-dependent phosphate cotransporter-1 (Pit-1) small interfering RNA and phosphonoformic acid (PFA), a Pit-1 inhibitor, were used to investigate the effects and mechanisms of Pit-1 on HPVC. Calcium content shown by Alizarin red staining, expression levels of Pit-1, and characteristic molecules for phenotypic transition of vascular smooth muscle cells were examined. RESULTS: Hyperphosphatemia induced the upregulation of Pit-1 expression, facilitated phenotypic transition of vascular smooth muscle cells, and led to HPVC in cellular and organ models. Treatment with Pit-1 small interfering RNA or PFA significantly inhibited Pit-1 expression, suppressed phenotypic transition, and attenuated HPVC. CONCLUSIONS: Our findings suggest that Pit-1 plays a pivotal role in the development of HPVC. The use of PFA as a Pit-1 inhibitor has the potential for therapeutic intervention in patients with HPVC. However, further rigorous clinical investigations are required to ensure the safety and efficacy of PFA before it can be considered for widespread implementation in clinical practice.

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

INTRODUCTION: 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). METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

ENPP1 in Blood and Bone: Skeletal and Soft Tissue Diseases Induced by ENPP1 Deficiency.

The enzyme ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) codes for a type 2 transmembrane glycoprotein that hydrolyzes extracellular ATP to generate pyrophosphate (PPi) and adenosine monophosphate, thereby contributing to downstream purinergic signaling pathways. The clinical phenotypes induced by ENPP1 deficiency are seemingly contradictory and include early-onset osteoporosis in middle-aged adults and life-threatening vascular calcifications in the large arteries of infants with generalized arterial calcification of infancy. The progressive overmineralization of soft tissue and concurrent undermineralization of skeleton also occur in the general medical population, where it is referred to as paradoxical mineralization to highlight the confusing pathophysiology. This review summarizes the clinical presentation and pathophysiology of paradoxical mineralization unveiled by ENPP1 deficiency and the bench-to-bedside development of a novel ENPP1 biologics designed to treat mineralization disorders in the rare disease and general medical population.

Vascular calcification and cellular signaling pathways as potential therapeutic targets.

Increased vascular calcification (VC) is observed in patients with cardiovascular diseases such as atherosclerosis, diabetes, and chronic kidney disease. VC is divided into three types according to its location: intimal, medial, and valvular. Various cellular signaling pathways are associated with VC, including the Wnt, mitogen-activated protein kinase, phosphatidylinositol-3 kinase/Akt, cyclic nucleotide-dependent protein kinase, protein kinase C, calcium/calmodulin-dependent kinase II, adenosine monophosphate-activated protein kinase/mammalian target of rapamycin, Ras homologous GTPase, apoptosis, Notch, and cytokine signaling pathways. In this review, we discuss the literature concerning the key cellular signaling pathways associated with VC and their role as potential therapeutic targets. Inhibitors to these pathways represent good candidates for use as potential therapeutic agents for the prevention and treatment of VC.

AMPK-mediated autophagy is involved in the protective effect of canagliflozin in the vitamin D3 plus nicotine calcification model in rats.

Vascular calcification (VC) is a major risk factor for cardiovascular events. A mutual interplay between inflammation, oxidative stress, apoptosis, and autophagy is implicated in its development. Herein, we aimed to evaluate the potential protective effects of canagliflozin in a vitamin D3 plus nicotine (VDN) model of VC, and to explore potential mechanisms. VC was induced by VDN in adult male Wistar rats on day one. Then, rats were randomly assigned into three groups to receive canagliflozin (10 mg or 20 mg/kg/day) or its vehicle for 4 weeks. Age-matched normal rats served as a control group. After euthanization, aorta and kidneys were harvested for biochemical and histopathological evaluation of calcification. Aortic markers of oxidative stress, alkaline phosphatase (ALP) activity, runt-related transcription factor (Runx2) and bone morphogenic protein-2 (BMP-2) levels were determined. Additionally, the protein expression of autophagic markers, LC3 and p62, and adenosine monophosphate activated protein kinase (AMPK) were also assessed in aortic homogenates. Canagliflozin dose-dependently improved renal function, enhanced the antioxidant capacity of aortic tissues and reduced calcium deposition in rat aortas and kidneys. Both doses of canagliflozin attenuated ALP and osteogenic markers while augmented the expression of autophagic markers and AMPK. Histopathological examination of aortas and kidneys by H&E and Von Kossa stain further support the beneficial effect of canagliflozin. Canagliflozin could alleviate VDN-induced vascular calcification, in a dose dependent manner, via its antioxidant effect and modulation of autophagy. Further studies are needed to verify whether this effect is a member or a class effect.

Roxadustat ameliorates vascular calcification in CKD rats by regulating HIF-2α/HIF-1α.

Vascular calcification (VC) is a common complication of chronic kidney disease (CKD). VC is a gene-regulated process similar to osteogenic differentiation. There are still no convincing schemes to prevent and reduce the development of VC. It has been reported that hypoxia-inducing factor 1α (HIF-1α) and endothelin-1(ET-1) are related to VC. In this study, we found that the expression of ET-1 and HIF-1α was enhanced after VC, the interaction between HIF-1α and ET-1 was confirmed by CO-IP and luciferase experiments. We found that ET-1 was an upregulated differential gene of calcified vascular smooth muscle cells (VSMCs) through gene sequencing. However, hypoxia-inducing factor 2α (HIF-2α) and HIF-1α have antagonistic effects on each other. HIF-1α is a pro-inflammatory cytokine, and HIF-2α can improve inflammation and fibrosis. Roxadustat, as a selective PHD3 inhibitor, preferentially activates HIF-2α. It is still unclear whether roxadustat improves VC in CKD by regulating the expression of HIF-2α/HIF-1α. Alizarin red staining and western blot as well as immunohistochemical results showed that roxadustat could significantly reduce the degree of vascular and VSMCs calcification in CKD rats. Serum HIF-1α and ET-1 were significantly decreased after roxadustat treatment. In addition, western blot results showed that roxadustat could decrease the expression of HIF-1α and ET-1 in vascular tissues and calcified VSMC, but HIF-2α expression significantly increased. Interestingly, our study confirmed that activation of HIF-1α or inhibition of HIF-2α reversed the ameliorating effect of roxadustat on VC, proving that the effect mediated by roxadustat is HIF-2α/HIF-1α dependent. We have demonstrated for the first time that roxadustat improves VC in CKD rats by regulating HIF-2α/HIF-1α, thus providing a new idea for the application of roxadustat in VC of CKD.