Citrate Supplementation Restores the Impaired Mineralisation Resulting from the Acidic Microenvironment: An In Vitro Study.

Chronic metabolic acidosis leads to bone-remodelling disorders based on excessive mineral matrix resorption and inhibition of bone formation, but also affects the homeostasis of citrate, which is an essential player in maintaining the acid-base balance and in driving the mineralisation process. This study aimed to investigate the impact of acidosis on the osteogenic properties of bone-forming cells and the effects of citrate supplementation in restoring the osteogenic features impaired by the acidic milieu. For this purpose, human mesenchymal stromal cells were cultured in an osteogenic medium and the extracellular matrix mineralisation was analysed at the micro- and nano-level, both in neutral and acidic conditions and after treatment with calcium citrate and potassium citrate. The acidic milieu significantly decreased the citrate release and hindered the organisation of the extracellular matrix, but the citrate supplementation increased collagen production and, particularly calcium citrate, promoted the mineralisation process. Moreover, the positive effect of citrate supplementation was observed also in the physiological microenvironment. This in vitro study proves that the mineral matrix organisation is influenced by citrate availability in the microenvironment surrounding bone-forming cells, thus providing a biological basis for using citrate-based supplements in the management of bone-remodelling disorders related to chronic low-grade acidosis.

Therapeutic use of tetrasodium ethylenediaminetetraacetic acid solution for treatment of subcutaneous ureteral bypass device mineralization in cats.

BACKGROUND: Subcutaneous ureteral bypass (SUB) device placement is an increasingly popular treatment option for decompression of ureteral obstruction in cats. Mineralization occlusion of the device occurs in a minority of cases but is the most common complication. OBJECTIVE: To evaluate a 2% tetrasodium ethylenediaminetetraacetic acid (tEDTA) solution for treatment of mineralization occlusion in cats with SUBs. ANIMALS: Six client-owned cats (8 obstructed devices). METHODS: Case series. Each cat was found to have device occlusion based on a combination of ultrasound examination, SUB irrigation, and failure to identify another cause of device obstruction. Each SUB was drained, irrigated using sterile saline, and infused with 1-2 mL of 2% tEDTA solution. Success was defined as normalization of flow during subsequent ultrasound visualization while irrigating. The volume and frequency of tEDTA instillations, time to achieve device patency, follow-up biochemical and ultrasound findings, and future reobstruction events were recorded. RESULTS: Resolution of mineralization was documented in all 8 SUBs. Reobstruction events occurred in 2 cats, all of which resolved after additional tEDTA infusions, but 1 cat ultimately required device exchange at 356 days from the first tEDTA infusion. In 1 cat, a single infusion was prematurely discontinued because of persistent pelvic dilatation after 1.25 mL of tEDTA had been instilled. No complications were observed. CONCLUSIONS AND CLINICAL IMPORTANCE: Tetrasodium EDTA infusions can be safely considered as a treatment option for mineralized SUB devices in cats. This solution was easily infused, well tolerated, and avoided the need for SUB device exchange in the majority of cats in which it was used.

Citrate attenuates vascular calcification in chronic renal failure rats.

Vascular calcification (VC) is a major contributor of cardiovascular dysfunction in chronic renal failure (CRF). Citrate binds calcium and inhibits the growth of calcium crystals. This present study intends to evaluate the effect of citrate on VC in adenine-induced CRF rats. The rats were randomly divided into five groups: the control group, the citrate control group, model group, model rats with low-dose treatment of citrate (216 mg/kg) and model rats with high-dose treatment of citrate (746 mg/kg). The rats were euthanized at 5 weeks with their blood and aorta in detection. The results showed that serum level of blood urea nitrogen, serum creatinine, phosphorus, calcium, and related renal failure function marker were elevated in the model group. Furthermore, the aortic calcium accumulation and alkaline phosphatase activity were significantly increased in the model group compared with control groups. Additionally, hematoxylin-eosin staining results demonstrated that the vascular calcification in aorta is significantly increased in the model group. Finally, the expression of VC-related proteins including bone morphogenetic protein and osteocalcin were increased in the model group, whereas alpha-smooth muscle actin was decreased in the model group compared with the control group. However, treatment with citrate caused a reversal effect of all the above events in a dose-dependent manner. In conclusion, citrate may attenuate vascular calcification in adenine-induced CRF rats.

Reversal of Vascular Calcification and Aneurysms in a Rat Model Using Dual Targeted Therapy with EDTA- and PGG-Loaded Nanoparticles.

Degeneration of elastic lamina and vascular calcification are common features of vascular pathology such as aortic aneurysms. We tested whether dual therapy with targeted nanoparticles (NPs) can remove mineral deposits (by delivery of a chelating agent, ethylene diamine tetraacetic acid (EDTA)) and restore elastic lamina (by delivery of a polyphenol, pentagalloyl glucose (PGG)) to reverse moderate aneurysm development. EDTA followed by PGG NP delivery led to reduction in macrophage recruitment, matrix metalloproteinase (MMP) activity, elastin degradation and calcification in the aorta as compared to delivery of control blank NPs. Such dual therapy restored vascular elastic lamina and improved vascular function as observed by improvement in circumferential strain. Therefore, dual targeted therapy may be an attractive option to remove mineral deposits and restore healthy arterial structures in moderately developed aneurysms.

Effect of photon induced photoacoustic streaming (PIPS) on bond strength to dentine of two root canal filling materials.

OBJECTIVES: The aim of this study was to evaluate the effect of photon induced photoacoustic streaming (PIPS) technique in combination with EDTA on bond strength of gutta-percha/AH Plus and Resilon/RealSeal SE root canal fillings to root dentine. MATERIALS AND METHODS: Forty freshly extracted human maxillary anterior teeth with intact straight roots, were instrumented endodontically with rotating ProTaper instruments and randomly divided into two experimental groups. In group 1 (n = 20), root canals were rinsed for 1 minute with 2 ml of 17% EDTA. In group 2 (n = 20), Er:YAG laser, with a 14 mm long 400 µ diameter tapered PIPS tip, was used for 1 minute with 2 ml of 17% EDTA. The laser parameters used were: 20 mJ per pulse, 15 Hz, 50 microsecond. In each experimental group, half of the root canals (n = 10) were obturated with gutta-percha/AH Plus and other half (n = 10) with Resilon/RealSeal SE. A micropush-out test was performed on sectiond specimens of the filled roots using a universal testing machine and resistance to failure plus failure modes were determined. RESULTS: Both gutta-percha/AH Plus groups had higher bond strength to root dentin than the Resilon/RealSeal SE groups (P < 0.05). The smear layer removal protocol, with EDTA only or combining PIPS technique with EDTA, had no influence on bond strength of either gutta-percha/AH Plus, or Resilon/RealSeal SE (P > 0.05). CONCLUSION: Within the limitations of this study, it was found that the application of the PIPS technique did not have an affect on the push-out bond strength of Resilon/RealSeal SE root canal filling to dentin nor on the gutta-percha/AH Plus. A significant difference in bond strength was noted between the two root canal filling materials. Lasers Surg. Med. 48:951-954, 2016. © 2016 Wiley Periodicals, Inc.

Edetate Disodium-Based Treatment for Secondary Prevention in Post-Myocardial Infarction Patients.

An abundance of data, known for decades, is available linking metals, such as lead and cadmium, with cardiovascular disease. However, the idea that these toxic metals could be a modifiable risk factor for atherosclerosis did not become apparent clinically until the completion of the Trial to Assess Chelation Therapy in 2012. This pivotal study was the first double-blind, randomized, controlled trial of its kind to demonstrate a clear improvement in cardiovascular outcomes with edetate disodium therapy in a secondary prevention, post-myocardial infarction population. This effect size was most striking in diabetic patients, where the efficacy of edetate disodium was comparable, if not superior, to that of current guideline-based therapies. Given the economic burden of diabetes and cardiovascular disease, the potential impact of this therapy could be enormous if the results of this study are replicated.

Safety and efficacy of a novel plastic stent coated with stone-dissolving agents for the treatment of biliary stones in a porcine model.

BACKGROUND AND STUDY AIM: We previously reported on a plastic stent that was coated with ethylenediaminetetraacetic acid (EDTA) and sodium cholate, which dissolved common bile duct (CBD) stones ex vivo. The aim of this study was to investigate the safety and efficacy of such stents on biliary stones in a live porcine model. METHODS: Stents without coating or with degradable membranes containing 0 % or 50 % EDTA and sodium cholate were inserted together with human CBD stones into the porcine CBD. Serum laboratory variables, histological examinations of the bile duct, and the weight change in stones were compared during and after stent placement for 6 months. RESULTS: A total of 16 pigs were included (5 no coating, 5 0 % coating, 6 50 % coating). Biliary stones showed decreased weight in all groups; however, stones in the group with 50 % coated stents showed a greater reduction in weight compared with the no coating and the 0 % coating groups (269 ±â€Š66 mg vs. 179 ±â€Š51 mg [P = 0.09]; 269 ±â€Š66 mg vs. 156 ±â€Š26 mg [P = 0.01], respectively). CONCLUSIONS: The plastic stent coated with 50 % agent enhanced CBD stone dissolution in vivo and may be a promising tool for patients with difficult biliary stones.

L-carnitine is a calcium chelator: a reason for its useful and toxic effects in biological systems.

BACKGROUND: Investigation of the direct link between l-carnitine (LC), a quaternary ammonium compound that facilitates the passage of unsaturated fatty acids into the mitochondrial matrix, and free calcium (Ca2+) is needed to explain a number of varying results obtained from different in vitro and in vivo studies of LC as a supplement. METHODS: The chemical structure of LC, which contains oxygen ligand atoms, prompted to measure its activity asa Ca2+ chelator. The measurement was carried out spectrophotometri cally by measuring the reduction in the formation of Ca2+-o-cresolphthalein complexone (Ca-CPC) in the presence of different doses of LC (0.075, 0.75, and 7.5 mM) compared to the control (0.0 mM LC). RESULTS: The effect of LC was measured as a free entity in solution and when added to human serum. Our results showed a significant decrease (p < 0.05) in the average absorbance of Ca-CPC in the presence of LC compared to the control. CONCLUSIONS: In conclusion, LC exhibits a significant Ca2+ chelating activity. As Ca2+ is vital in the biochemical and physiological processes of living cells, LC could be affecting the calcium-dependent biological systems by limiting the levels of free Ca2+. Examples include decelerating the blood clotting process, amplifying the effect of anticoagulants, reducing nitric oxide synthase activity, inhibiting

Quality-of-life outcomes with a disodium EDTA chelation regimen for coronary disease: results from the trial to assess chelation therapy randomized trial.

BACKGROUND: The National Institutes of Health.funded Trial to Assess Chelation Therapy (TACT) randomized 1708 stablecoronary disease patients aged .50 years who were .6 months post.myocardial infarction (2003.2010) to 40 infusions ofa multicomponent EDTA chelation solution or placebo. Chelation reduced the primary composite end point of mortality,recurrent myocardial infarction, stroke, coronary revascularization, or hospitalization for angina (hazard ratio, 0.82; 95%confidence interval, 0.69.0.99; P=0.035). METHODS AND RESULTS: In a randomly selected subset of 911 patients, we prospectively collected a battery of quality-of-life(QOL) instruments at baseline and at 6, 12, and 24 months after randomization. The prespecified primary QOL measures were the Duke Activity Status Index (Table I in the Data Supplement) and the Medical Outcomes Study Short-Form 36 Mental Health Inventory-5. All comparisons were by intention to treat. Baseline clinical and QOL variables were well balanced in the 451 patients randomized to chelation and in the 460 patients randomized to placebo. The Duke Activity Status Index improved in both groups during the first 6 months of therapy, but we found no evidence for a treatment-related difference (mean difference [chelation.placebo] during follow-up, 0.9 [95% confidence interval, .0.7 to 2.6; P=0.27]).There was no statistically significant evidence of a treatment-related difference in the Mental Health Inventory-5 during follow-up (mean difference, 1.0; 95% confidence interval, .0.1 to 2.0; P=0.08). None of the secondary QOL measures showed a consistent treatment-related difference. CONCLUSIONS: In stable, predominantly asymptomatic coronary disease patients with a history of myocardial infarction,EDTA chelation therapy did not have a detectable effect on QOL during 2 years of follow-up. CLINICAL TRIAL REGISTRATION: URL: http://clinicaltrials.gov. Unique identifier: NCT00044213.