Titanium dioxide nanoparticles promote arrhythmias via a direct interaction with rat cardiac tissue

Abstract

BackgroundIn light of recent developments in nanotechnologies, interest is growing to better comprehend the interaction of nanoparticles with body tissues, in particular within the cardiovascular system. Attention has recently focused on the link between environmental pollution and cardiovascular diseases. Nanoparticles <50 nm in size are known to pass the alveolar–pulmonary barrier, enter into bloodstream and induce inflammation, but the direct pathogenic mechanisms still need to be evaluated. We thus focused our attention on titanium dioxide (TiO2) nanoparticles, the most diffuse nanomaterial in polluted environments and one generally considered inert for the human body.MethodsWe conducted functional studies on isolated adult rat cardiomyocytes exposed acutely in vitro to TiO2 and on healthy rats administered a single dose of 2 mg/Kg TiO2 NPs via the trachea. Transmission electron microscopy was used to verify the actual presence of TiO2 nanoparticles within cardiac tissue, toxicological assays were used to assess lipid peroxidation and DNA tissue damage, and an in silico method was used to model the effect on action potential.ResultsVentricular myocytes exposed in vitro to TiO2 had significantly reduced action potential duration, impairment of sarcomere shortening and decreased stability of resting membrane potential. In vivo, a single intra-tracheal administration of saline solution containing TiO2 nanoparticles increased cardiac conduction velocity and tissue excitability, resulting in an enhanced propensity for inducible arrhythmias. Computational modeling of ventricular action potential indicated that a membrane leakage could account for the nanoparticle-induced effects measured on real cardiomyocytes.ConclusionsAcute exposure to TiO2 nanoparticles acutely alters cardiac excitability and increases the likelihood of arrhythmic events.Electronic supplementary materialThe online version of this article (doi:10.1186/s12989-014-0063-3) contains supplementary material, which is available to authorized users.

Zinc oxide nanoparticle-induced atherosclerotic alterations in vitro and in vivo

“…9,13,23 There are two main mechanisms to explain how pulmonary NPs exposure can initiate cardiovascular responses. One hypothesis states that NPs deposited in the lung elicit local inflammatory responses via oxidative stress that further develop into systemic oxidative stress/inflammation.…”

“…12 A recent animal study has shown that a single intratracheal administration of saline solution containing TiO 2 nanoparticles increases cardiac conduction velocity and tissue excitability, resulting in an enhanced propensity for inducible arrhythmias. 13 In addition, both multiwalled carbon nanotubes and ZnO-NPs have been demonstrated to induce procoagulant effects.…”

Effect of titanium dioxide nanoparticles on the cardiovascular system after oral administration

“…Consistent with this, some respiratory toxicity studies have shown that TiO 2 NPs indeed can affect the cardiovascular system. Savi et al (2014) found that in vivo a single intra-tracheal administration of saline solution containing TiO 2 NPs at dose of 2 mg/kg increased cardiac conduction velocity and tissue excitability on healthy rats, resulting in an enhanced propensity for inducible arrhythmias). Kan et al (2014) demonstrated that pulmonary inhalation of ultrafine titanium dioxide (UF TiO 2 ) significantly increased heart rate and elevated mean and diastolic blood pressure in response to norepinephrine (Kan et al, 2014).…”

Synthesis and Characterization of Zinc Oxide and Iron Oxide Nanoparticles Using Sesbania grandiflora Leaf Extract as Reducing Agent

“…Similar kind of result was found by [20] synthesizing the zinc oxide nanoparticles by micro emulsion method. From the UV-visible spectrometer analysis concluded that zinc oxide and iron oxide nanoparticles had an intense absorbance at ∼250 nm which indicates that the synthesized particles were photosensitive in UV region [21].…”