scholarly journals High Magnesium and Sirolimus on Rabbit Vascular Cells—An In Vitro Proof of Concept

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1970
Author(s):  
Giorgia Fedele ◽  
Sara Castiglioni ◽  
Jeanette A. Maier ◽  
Laura Locatelli

Drug-eluting bioresorbable scaffolds represent the last frontier in the field of angioplasty and stenting to treat coronary artery disease, one of the leading causes of morbidity and mortality worldwide. In particular, sirolimus-eluting magnesium-based scaffolds were recently introduced in clinical practice. Magnesium alloys are biocompatible and dissolve in body fluids, thus determining high concentrations of magnesium in the local microenvironment. Since magnesium regulates cell growth, we asked whether high levels of magnesium might interfere with the antiproliferative action of sirolimus. We performed in vitro experiments on rabbit coronary artery endothelial and smooth muscle cells (rCAEC and rSMC, respectively). The cells were treated with sirolimus in the presence of different concentrations of extracellular magnesium. Sirolimus inhibits rCAEC proliferation only in physiological concentrations of magnesium, while high concentrations prevent this effect. On the contrary, high extracellular magnesium does not rescue rSMC growth arrest by sirolimus and accentuates the inhibitory effect of the drug on cell migration. Importantly, sirolimus and magnesium do not impair rSMC response to nitric oxide. If translated into a clinical setting, these results suggest that, in the presence of sirolimus, local increases of magnesium concentration maintain normal endothelial proliferative capacity and function without affecting rSMC growth inhibition and response to vasodilators.

1982 ◽  
Vol 47 (02) ◽  
pp. 150-153 ◽  
Author(s):  
P Han ◽  
C Boatwright ◽  
N G Ardlie

SummaryVarious cardiovascular drugs such as nitrates and propranolol, used in the treatment of coronary artery disease have been shown to have an antiplatelet effect. We have studied the in vitro effects of two antiarrhythmic drugs, verapamil and disopyramide, and have shown their inhibitory effect on platelet function. Verapamil, a calcium channel blocker, inhibited the second phase of platelet aggregation induced by adenosine diphosphate (ADP) and inhibited aggregation induced by collagen. Disopyramide similarly inhibited the second phase of platelet aggregation caused by ADP and aggregation induced by collagen. Either drug in synergism with propranolol inhibited ADP or collagen-induced platelet aggregation. Disopyramide at high concentrations inhibited arachidonic add whereas verapamil was without effect. Verapamil, but not disopyramide, inhibited aggregation induced by the ionophore A23187.


1987 ◽  
Author(s):  
Lars Wallentin ◽  
Ingyar Nyman ◽  
ULF Berglund ◽  
Eva Swahn

In unstable coronary artery disease (UCAD), i.e. unstable angina pectoris (UAP) or non-Q-myocardial infarction (NMI), treatment with heparin or ASA have given encouraging results. The present study attempts to verify the effects of i.v. heparin (5 days) and to evaluate the utility of ASA 75 mg/day (one year). Patients, admitted because of chest pain, who either develops NMI or signs of ischemia in resting or exercise ECG.s are included. Within 72 hours patients are randomized to obtain Heparin+ASA, Heparin+Placebo, Placebo + ASA or Placebo+Placebo . Platelet reactivity is studied in vitro in platelet rich plasma (PRP) in a subgroup of patients.The aggregation response is studied after addition of collagen and ADP and after preincubation with prostacyclin before aggregation with ADP. The figures present results from 85 randomized patients tested before, 5 days, one month and one year after start of therapy.Conclusion: In patients with unstable CAD long term treatment with ASA 75 mg/day inhibits collagen induced platelet aggregation and hampers the ADP response. I.v. heparin tends to raise platelet reactivity and reduce the inhibitory effect of prostacyclin. Heparin induced platelet activation is reduced by simultaneous ASA therapy.


1989 ◽  
Vol 61 (02) ◽  
pp. 254-258 ◽  
Author(s):  
Margaret L Rand ◽  
Peter L Gross ◽  
Donna M Jakowec ◽  
Marian A Packham ◽  
J Fraser Mustard

SummaryEthanol, at physiologically tolerable concentrations, inhibits platelet responses to low concentrations of collagen or thrombin, but does not inhibit responses of washed rabbit platelets stimulated with high concentrations of ADP, collagen, or thrombin. However, when platelet responses to high concentrations of collagen or thrombin had been partially inhibited by prostacyclin (PGI2), ethanol had additional inhibitory effects on aggregation and secretion. These effects were also observed with aspirin- treated platelets stimulated with thrombin. Ethanol had no further inhibitory effect on aggregation of platelets stimulated with ADP, or the combination of ADP and epinephrine. Thus, the inhibitory effects of ethanol on platelet responses in the presence of PGI2 were very similar to its inhibitory effects in the absence of PGI2, when platelets were stimulated with lower concentrations of collagen or thrombin. Ethanol did not appear to exert its inhibitory effects by increasing cyclic AMP above basal levels and the additional inhibitory effects of ethanol in the presence of PGI2 did not appear to be brought about by further increases in platelet cyclic AMP levels.


2018 ◽  
Vol 24 (4) ◽  
pp. 397-401
Author(s):  
Gianluca Rigatelli ◽  
Marco Zuin

Backgrounds: Drug coated balloons (DCBs) are new on stented-based anti-proliferative drug delivery systems, recently introduced in interventional cardiology. Their primary aim is to transfer an anti-proliferative drug to reduce the subsequent neo-intima hyperplasia and to maintain the normal vessel diameter and function. Methods: A review of the most recent influential studies about DCBs in all the fields of interventional cardiology has been performed. Results: As demonstrated by different studies, DCBs have different theoretical advantages over Drug Eluting Stents (DESs), especially for the treatment of some endovascular lesions, as In-Stent Restenosis (ISR), coronary bifurcations, small vessels disease and peripheral artery disease at femoropopliteal and below the knee sites. Conclusion: Despite the need of further studies are needed to elucidate the optimal use of DCBs their current use in interventional cardiology appears promising.


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