Manganese ferrite-based nanoparticles induce ex vivo, but not in vivo, cardiovascular effects

Abstract

Magnetic nanoparticles (MNPs) have been used for various biomedical applications. Importantly, manganese ferrite-based nanoparticles have useful magnetic resonance imaging characteristics and potential for hyperthermia treatment, but their effects in the cardiovascular system are poorly reported. Thus, the objectives of this study were to determine the cardiovascular effects of three different types of manganese ferrite-based magnetic nanoparticles: citrate-coated (CiMNPs); tripolyphosphate-coated (PhMNPs); and bare magnetic nanoparticles (BaMNPs). The samples were characterized by vibrating sample magnetometer, X-ray diffraction, dynamic light scattering, and transmission electron microscopy. The direct effects of the MNPs on cardiac contractility were evaluated in isolated perfused rat hearts. The CiMNPs, but not PhMNPs and BaMNPs, induced a transient decrease in the left ventricular end-systolic pressure. The PhMNPs and BaMNPs, but not CiMNPs, induced an increase in left ventricular end-diastolic pressure, which resulted in a decrease in a left ventricular end developed pressure. Indeed, PhMNPs and BaMNPs also caused a decrease in the maximal rate of left ventricular pressure rise (+dP/dt) and maximal rate of left ventricular pressure decline (−dP/dt). The three MNPs studied induced an increase in the perfusion pressure of isolated hearts. BaMNPs, but not PhMNPs or CiMNPs, induced a slight vasorelaxant effect in the isolated aortic rings. None of the MNPs were able to change heart rate or arterial blood pressure in conscious rats. In summary, although the MNPs were able to induce effects ex vivo, no significant changes were observed in vivo. Thus, given the proper dosages, these MNPs should be considered for possible therapeutic applications.

Precise determination of the heat delivery duringin vivomagnetic nanoparticle hyperthermia with infrared thermography

“…This nanoparticle was chosen because of its excellent response at low field amplitude in the frequency studied (301 kHz) (Branquinho et al 2013, Rodrigues et al 2013. Details of the synthesis of this nanoparticle can be found elsewhere (Branquinho et al 2013, Rodrigues et al 2013, Nunes et al 2014. For the coating process, the magnetic material was diluted at room temperature in approximately 50 ml of water and then 2 g of DMSA (Sigma) was added.…”

Manganese Ferrite Nanoparticles (MnFe2O4): Size Dependence for Hyperthermia and Negative/Positive Contrast Enhancement in MRI

“…MnFe 2 O 4 nanoparticles are of great interest for their remarkable inherent biocompatibility because of the presence of Mn 2+ ions, tunable magnetic properties, higher transition temperature, and excellent chemical stability for room temperature applications. There are recent reports on MnFe 2 O 4 nanoparticles as one novel agent for magnetic hyperthermia and MRI contrast [ 42 , 43 , 44 , 45 ]. Manganese based ferrites have added advantages than other cations because manganese can be consumed in the amount of 0.67–4.99 mg with a mean value of 2.21 mg per day [ 46 ].…”

“…Ferrites are ideal MRI contrast agents for higher transverse relaxation time (T 2 ), and MnFe 2 O 4 is one among them [ 45 ]. However, recently, applications of MnFe 2 O 4 are explored as the contrast agent for magnetic resonance angiography (MRA).…”

Real-time in vivo monitoring of magnetic nanoparticles in the bloodstream by AC biosusceptometry

“…Another aspect that has drawn attention with regard to intravenous nanoparticle applications is the physiological effect of the administration protocol. The cardiovascular effects of intravenous MNP administration have been investigated [ 28 , 29 ].…”