Biodistribution and toxicity of epitope-functionalized dextran iron oxide nanoparticles in a pregnant murine model

Safety of nanoparticle therapies during pregnancy: A systematic review and meta-analysis

The exclusion of pregnant women from clinical trials has led to insufficient safety data for many treatments, making it necessary to evaluate their potential benefits and risks during preclinical stages. Nanomedicines show potential for reduced toxicity but there is limited evidence about their safety for pregnant women and their fetuses. We conducted the first systematic review and meta-analysis of the effect of nanoparticles (NPs) on a key outcome of fetal toxicity (low birth weight) in murine models. In the meta-analysis of mouse models, negatively charged NPs tended to decrease birth weight (-69.8 mg, 95 % CI: -196 to 56.5), as did small (-191 mg, 95 % CI: -369 to -13.3) and plain inorganic nanosystems (-249 mg, 95 % CI: -535 to 37.4). In contrast, positively charged NPs resulted in increased birth weight (+29.3 mg, 95 % CI: 23.4 to 35.2). All findings were validated in studies with low heterogeneity and low risk of publication bias. Neither large NPs (+4.37 mg; 95 % CI: -45.3 to 54.0) nor polymer-coated NPs (+16.5 mg; 95 % CI: -44.7 to 77.6) had any clear association with birth weight. Similar results were observed in other models and experimental designs from articles not included in the meta-analysis, although no conclusions were drawn for other parameters due to high variability. Our findings pave the way for future research and the rational development of safer nanomedicines for use during pregnancy.

A minimally invasive thrombotic model to study stroke in awake mice

Experimental stroke models in rodents are essential for mechanistic studies and therapeutic development. However, these models have several limitations negatively impacting their translational relevance. Here we aimed to develop a minimally invasive thrombotic stroke model through magnetic particle delivery that does not require craniotomy, is amenable to reperfusion therapy, can be combined with in vivo imaging modalities, and can be performed in awake mice. We found that the model results in reproducible cortical infarcts within the middle cerebral artery (MCA) territory with cytologic and immune changes similar to that observed with more invasive distal MCA occlusion models. Importantly, the injury produced by the model was ameliorated by tissue plasminogen activator (tPA) administration. We also show that MCA occlusion in awake animals results in bigger ischemic lesions independent of day/night cycle. Magnetic particle delivery had no overt effects on physiologic parameters and systemic immune biomarkers. In conclusion, we developed a novel stroke model in mice that fulfills many requirements for modeling human stroke.

In Vitro and In Vivo Biological Assays of Dextran Coated Iron Oxide Aqueous Magnetic Fluids

The iron oxide nanoparticles coated with different surface coatings were studied and characterized by multiple physicochemical and biological methods. The present paper aims at estimating the toxicity in vitro and in vivo of dextran coated iron oxide aqueous magnetic fluids. The in vitro studies were conducted by quantifying the viability of HeLa cells after their incubation with the samples (concentrations of 62.5−125−250−500 μg/mL at different time intervals). The estimation of the toxicity in vivo of administering dextran coated iron oxide aqueous magnetic fluids (DIO-AMF) with hydrodynamic diameter of 25.73 ± 4 nm to Male Brown Norway rats has been made. Different concentrations (62.5−125−250−500 μg/mL) of dextran coated iron oxide aqueous magnetic fluids were administered for 7 consecutive days. Hematology and biochemistry of the Male Brown Norway rats assessment was performed at various time intervals (24−72 h and 21−28 days) after intra-peritoneal injection. The results showed that high concentrations of DIO-AMF (250 and 500 μg/mL) significantly increased white blood cells, red blood cells, hemoglobin and hematocrit compared to the values obtained for the control group (p < 0.05). Moreover, following the administration of DIO-AMF, the levels of alkaline phosphatase and aspartate aminotransferase increased compared to the control group (p < 0.05). After DIO-AMF administration, no significant difference was observed in the levels of alanine aminotransferase, gamma-glutamyl transpeptidase, urea and creatinine compared to the control group (p < 0.05). The results of the present study showed that dextran coated iron oxide aqueous magnetic fluids in concentrations lower than 250 μg/mL are reliable for medical and pharmaceutical applications.

Assessment of the potential toxic effect of magnetite nanoparticles on the male reproductive system based on immunological and molecular studies

Magnetite nanoparticles (MNPs) are the most conventional type of iron oxide nanoparticles used in the food industrial processes, removal of heavy metals, and biomedical applications in vivo or in vitro. Until now, there is no sufficient information that can confirm its effect on the body's immune system and reproductive health in males. The purpose of this research is to estimate the immunotoxic and reproductive toxic effects of MNPs in male rats. This study included 36 adult male albino rats divided into three groups. The experimental groups were intraperitoneally injected with MNPs at doses of 5 and 10 mg/kg body weight 3 times/week for 60 days, while the control group was injected with saline solution. MNPs caused a significant decrease in the body weight change of the high-treated group. MNPs produced changes in the lymphocyte proliferation rate which referred to a significant immunotoxic effect measured by the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-di-phenyltetrazolium bromide reduction method. The testicular tissue of male-treated rats showed some moderate and severe degenerative changes. The sperm parameters of count, motility, and viability were significantly decreased. Sperm morphological abnormalities were detected in all treated animals. MNPs produced a significant decrease in testosterone levels, increased the level of malondialdehyde, impaired the activity of the antioxidant enzymes and induced testicular DNA damage. In conclusion, MNPs affected the normal immune state in male rats and facilitated the generation of reactive oxygen species subsequently triggering testicular oxidative stress damages. All these consequences had a negative impact on male reproductive health.

Proteomics unite traditional toxicological assessment methods to evaluate the toxicity of iron oxide nanoparticles

Iron oxide nanoparticles (IONPs) are the first generation of nanomaterials approved by the Food and Drug Administration for use as imaging agents and for the treatment of iron deficiency in chronic kidney disease. However, several IONPs-based imaging agents have been withdrawn because of toxic effects and the poor understanding of the underlying mechanisms. This study aimed to evaluate IONPs toxicity and to elucidate the underlying mechanism after intravenous administration in rats. Seven-week-old rats were intravenously administered IONPs at doses of 0, 10, 30, and 90 mg/kg body weight for 14 consecutive days. Toxicity and molecular perturbations were evaluated using traditional toxicological assessment methods and proteomics approaches, respectively. The administration of 90 mg/kg IONPs induced mild toxic effects, including abnormal clinical signs, lower body weight gain, changes in serum biochemical and hematological parameters, and increased organ coefficients in the spleen, liver, heart, and kidneys. Toxicokinetics, tissue distribution, histopathological, and transmission electron microscopy analyses revealed that the spleen was the primary organ for IONPs elimination from the systemic circulation and that the macrophage lysosomes were the main organelles of IONPs accumulation after intravenous administration. We identified 197 upregulated and 75 downregulated proteins in the spleen following IONPs administration by proteomics. Mechanically, the AKT/mTOR/TFEB signaling pathway facilitated autophagy and lysosomal activation in splenic macrophages. This is the first study to elucidate the mechanism of IONPs toxicity by combining proteomics with traditional methods for toxicity assessment.

Toxicity and biodistribution assessment of curcumin-coated iron oxide nanoparticles: Multidose administration

AIM

Iron oxide nanoparticles (IONPs) have been widely used in diagnosis, drug delivery, and therapy. However, the biodistribution and toxicity profile of IONPs remain debatable and incomplete, thus limiting their further use. We predict that coating iron oxide nanoparticles using curcumin (Cur-IONPs) will provide an advantage for their safety profile.

MATERIALS AND METHODS

In this study, an evaluation of the multidose effect (6 doses of 5 mg/kg Cur-IONPs to male BALB/c mice, on alternating days for two weeks) on the toxicity and biodistribution of Cur-IONPs was conducted.

KEY FINDINGS

Serum biochemical analysis demonstrated no significant difference in enzyme levels in the liver and kidney between the Cur-IONP-treated and control groups. Blood glucose level measurements showed a nonsignificant change between groups. However, the serum iron concentration was found to initially increase significantly but then decreased at 10 days after the final injection. Histopathological examination of the liver, spleen, kidneys, and brain showed no abnormalities or differences between the Cur-IONP-treated and control groups. There were no abnormal changes in mouse body weight. The biodistribution results showed that Cur-IONPs accumulated mainly in the liver, spleen, and brain, while almost no Cur-IONPs were found in the kidney. The iron content in the liver remained high even 10 days after the final injection, while the iron content in the spleen and brain had returned to normal levels by this time point, indicating their complete clearance.

SIGNIFICANCE

These results are significant and promising for the further application of Cur-IONPs as theragnostic nanoparticles.

The Intrinsic Biological Identities of Iron Oxide Nanoparticles and Their Coatings: Unexplored Territory for Combinatorial Therapies

Over the last 20 years, iron oxide nanoparticles (IONPs) have been the subject of increasing investigation due to their potential use as theranostic agents. Their unique physical properties (physical identity), ample possibilities for surface modifications (synthetic identity), and the complex dynamics of their interaction with biological systems (biological identity) make IONPs a unique and fruitful resource for developing magnetic field-based therapeutic and diagnostic approaches to the treatment of diseases such as cancer. Like all nanomaterials, IONPs also interact with different cell types in vivo, a characteristic that ultimately determines their activity over the short and long term. Cells of the mononuclear phagocytic system (macrophages), dendritic cells (DCs), and endothelial cells (ECs) are engaged in the bulk of IONP encounters in the organism, and also determine IONP biodistribution. Therefore, the biological effects that IONPs trigger in these cells (biological identity) are of utmost importance to better understand and refine the efficacy of IONP-based theranostics. In the present review, which is focused on anti-cancer therapy, we discuss recent findings on the biological identities of IONPs, particularly as concerns their interactions with myeloid, endothelial, and tumor cells. Furthermore, we thoroughly discuss current understandings of the basic molecular mechanisms and complex interactions that govern IONP biological identity, and how these traits could be used as a stepping stone for future research.