Biomedical Engineering Reference
In-Depth Information
Gojova et al.
49
found that the incubation of human aortic endothelial cells (HAECs) with differ-
ent concentrations (0.001-50 μg/mL) of Fe
2
O
3
nanoparticles for 1-8 h did not change the expression
levels of mRNA and proteins of the three inflammatory markers (ICAM-1, IL-8, and MCP-1) as com-
pared to the untreated control, indicating the absence of an inflammatory response. Sun et al.
50
found
that Fe
2
O
3
and Fe
3
O
4
nanoparticles did not have significant effects on the cytotoxicity, permeability,
and inflammation response in human cardiac microvascular endothelial cells (HCMECs) within the
concentration range of 0.001-100 μg/mL after 12-24 h of exposure. Au et al.
51
demonstrated that
ESCs labeled with 50 μg/mL superparamagnetic iron oxide nanoparticles (SPIONPs) for 24 h showed
cardiogenic capacities similar to their unlabeled counterparts, and SPIONPs labeling did not affect
the calcium-handling property of ESC-derived cardiomyocytes. In another study, Mahmoudi et al.
52
found that human cardiac myocytes (HCMs) were tolerable to various SPIONPs including negatively
charged, positively charged, and bare SPIONPs, showing IC
50
values between 20-30 mM.
On the other hand, magnemite γ-Fe
2
O
3
nanoparticles of around 10 nm caused the death of HUVECs
within 24 h of exposure, and an even more severe drop-off of cell viability was revealed after 48 h and
persisted until 72 h.
53
It was interesting to note that this effect was not dose related, because a similar
cell viability was observed at concentrations ranging from 1 to 100 μg/mL. When administered to
Wistar rats via a single IV injection at the dose of 0.8 mg/kg, the γ-Fe
2
O
3
nanoparticles did not induce
any toxic effects after 2 weeks as examined by staining tissues with hematoxylin and eosin. As to
the blood parameters at the end of the experiments, white blood cells showed an increased number,
suggesting an inflammatory process, while the red blood cell number remained unchanged, indicat-
ing the low toxicity of these particles toward erythrocytes.
53
Iversen et al.
54
intravenously injected
PAA-coated γ-Fe
2
O
3
nanoparticles (10 mg/kg) into healthy BALB/cJ mice, a commonly use inbred
which is susceptible to developing the demyelinating disease upon infection, and monitored the car-
diovascular effects. It was found that the arterial acid-base status did not change over the next 12 h
after injection, neither did the arterial PCO
2,
or (HCO
−
). However, the MAP decreased 12-24 h after
inject ion (111.1 ± 11.5 vs. 123.0 ± 6.1/min), associated with a decreased contractility of small mesen-
teric arteries as revealed by myography to characterize endothelial function.
12.2.3.3 Quantum Dots
Semiconductor quantum dots (QDs) have drawn great interests because of their superior optical prop-
erties and wide utilization in biological and biomedical studies. Most QDs are composed of heavy
metals such as cadmium (Cd), selenide (Se), and/or tellurium (Te), which have hepatic, renal, neuro-
logic, and/or genetic toxicity as ions in solution.
55
Recently, there have been intense concerns on the
toxicity assessments of QDs,
56
while their cardiovascular effects are still less frequently reported.
The IV application of multimodal, silica-shelled QDs in rats at the dose of 80 pmol did not show
significant acute cardiovascular toxicity.
57
10 min after the injection, the heart rate increased slightly
with a subsequent normalization to baseline levels within 40 min. The blood pressure was stable
within 20 min after the injection and decreased about 10% after 80 min. In addition, the QDs did not
affect the diameter and structure of the blood vessels.
57
In another study, biocompatible, lysine cross-
linked mercaptoundecanoic acid (MUA) CdSe
0.25
Te
0.75
/CdS QDs were used as a near-infrared (NIR)
probe, and the long-term toxicity was investigated.
58
Results from histological analyses showed that no
toxic effects were found 100 days after IV injection in the hearts of mice with 10.5 mg/kg of NIR QDs.
Haque et al.
59
intraperitoneally injected mercaptopropionic acid (MPA)-conjugated CdSe/CdS
QDs into BALB/c mice every 3 days for a period of 15 days with various doses of QDs (0, 5, 10, and
25 mg/kg). The QDs were not observed in the heart, and the histopathological examination did not
show any toxicity against the heart. Zhang et al.
60
demonstrated that the incubation of thioglycolic
acid (TGA)-CdTe QDs affected the heartbeats of zebrafish embryos, indicating cardiovascular tox-
icity. Treatments with 25 and 50 nM QDs resulted in a significantly lowered heartbeat as compared
to the control and 1 nM treatment; notably, even lower heartbeats were observed with 100, 200, and
300 nM treatments.
