Iron-carbohydrate complexes treating iron anaemia: Understanding the nano-structure and interactions with proteins through orthogonal characterisation

Evaluation of therapeutic response and tolerability to intravenous iron sucrose and ferric carboxymaltose among pregnant women with iron?deficiency anemia: A 6?year experience in a tertiary care center

Iron-deficiency anemia (IDA) is a global health concern in pregnancy associated with adverse fetal and maternal outcomes. The present study aimed to evaluate and compare the therapeutic response and tolerability of intravenous (IV) iron sucrose and ferric carboxymaltose (FCM) administered to pregnant women with IDA. The present prospective observational study was conducted among 334 pregnant women who were in the second or third trimester of pregnancy with moderate to severe IDA and who were treated with IV iron sucrose or FCM at a large tertiary care center between April, 2018 and March, 2024. The therapeutic response was assessed by analyzing the increase in hemoglobin (Hb) and serum ferritin levels at 3 and 6 weeks following the first dose of IV iron treatment. Tolerability was assessed by analyzing the adverse events to drug administration. A statistically significant increase in the mean Hb and serum ferritin levels was observed in both the iron sucrose and FCM groups at 3 and 6 weeks post-infusion (P<0.0001 for all); however, the increase in the FCM group was significantly higher (P<0.0001) than that in the iron sucrose group. Minor temporary adverse drug reactions were comparable (P=0.232) between the both treatment groups, with no major serious adverse events observed in any group. IV iron sucrose and FCM both were efficacious and well tolerated in pregnant women with moderate to severe IDA during the second and third trimester. However, there was an improved overall response to FCM as it caused a greater increase in the Hb and serum ferritin levels than iron sucrose. Therefore, FCM is recommended as an effective and safe alternative to iron sucrose for the treatment of IDA during pregnancy.

Best practice for the size analysis of nanomedicines - An iron sucrose case study

Iron sucrose is used in the parenteral treatment of iron deficiency anaemia. A number of iron sucrose similars have been developed alongside the original product. These products consist of colloidal iron with particles in the nanometre range stabilised by sucrose molecules. Dynamic light scattering (DLS) is the method of choice for the qualification of iron sucrose products in terms of particle size. However, the broad range of instrumentation and accessories available today for the execution of these measurements requires that best laboratory practice is established to ensure measurement comparability and consistent product quality. In this work, we have examined the measurement of iron sucrose particle size by DLS using a range of instrument models and manufacturers and compared results. We performed transmission electron microscopy with cryogenic capability to support DLS data interpretation. We find that DLS results are consistent when equivalent settings are selected across instruments, we discuss the experimental parameters of importance for high-quality measurements and present preliminary data for emerging modalities. Although focussed on iron sucrose products, the outcome of this work is relevant to the analysis of other types of nanoparticle-based products.

Molecular mechanism of enhancing antitumor activity through the interaction between monosaccharides and human serum albumin

This study investigated the molecular mechanisms of the interactions between three antitumor active monosaccharides and human serum albumin (HSA) using spectroscopic and electrochemical analyses, supplemented by molecular docking simulations. The antitumor efficacy of these monosaccharides can be significantly enhanced by covalent drug coupling, while HSA, with its long half-life and low immunogenicity, provides new opportunities for the development of advanced antitumor drug delivery systems. The results showed that these monosaccharides effectively burst the fluorescence of HSA. Thermodynamic analysis revealed that Fucose undergoes a spontaneous, exothermic process that decreases entropy, while the binding of Mannose and Galactose is entropy-driven. Notably, the addition of these three monosaccharides slightly compacts the structure of HSA, stabilizing its transport and delivery in vivo, with the binding strength categorized as Fucose > Mannose > Galactose. These variations in binding constants explain the differences in efficacy and potential side effects in antitumor therapy. Further studies have shown that the interaction between monosaccharides and HSA improves drug stability and targeting, thereby enhancing antitumor activity. An in-depth study of these interactions may provide new insights into the design and optimization of antitumor drugs and the further development of novel antitumor therapies.

Go with the flow: An in vitro model of a mature endothelium for the study of the bioresponse of IV injectable nanomedicines

The first exposure of intravenously (IV) administered nanomedicines in vivo is to endothelial cells (ECs) lining blood vessels. While it is known that in vitro endothelium models to assess responses to circulating nanoparticles require shear stress, there is no consensus on when and how to include it in the experimental design. Our experimental workflow integrates shear stress by featuring a flow-induced mature endothelium (14 days) and a flow-mediated nanoparticle treatment. The mature endothelium model exhibited distinct features that indicated a structurally stable and quiescent monolayer. Upon treatment with iron sucrose under dynamic conditions, there was a lower nanoparticle uptake, lower cytotoxicity, and decreased expression of activation markers compared to the static control. This response was attributed to glycocalyx expression, predominantly observed on the mature endothelium. In conclusion, our proposed in vitro endothelium model can be leveraged to understand the dynamics of IV injectable nanomedicines at the initial nano-bio interface in veins immediately post-injection.

Nano-scale characterization of iron-carbohydrate complexes by cryogenic scanning transmission electron microscopy: Building the bridge to biorelevant characterization

Iron deficiency and iron deficiency anemia pose significant health challenges worldwide. Iron carbohydrate nanoparticles administered intravenously are a mainstay of treatment to deliver elemental iron safely and effectively. However, despite decades of clinical use, a complete understanding of their physical structure and the significance for their behavior, particularly at the nano-bio interface, is still lacking, underscoring the need to employ more sophisticated characterization methods. Our study used cryogenic Scanning Transmission Electron Microscopy (cryo-STEM) to examine iron carbohydrate nanoparticle morphology. This method builds upon previous research, where direct visualization of the iron cores in these complexes was achieved using cryogenic Transmission Electron Microscopy (cryo-TEM). Our study confirms that the average size of the iron cores within these nanoparticles is approximately 2 nm across all iron-based products studied. Furthermore, our investigation revealed the existence of discernible cluster-like morphologies, not only for ferumoxytol, as previously reported, but also within all the examined iron-carbohydrate products. The application of cryo-STEM for the analyses of product morphologies provides high-contrast and high-resolution images of the nanoparticles, and facilitates the characterization at liquid nitrogen temperature, thereby preserving the structural integrity of these complex samples. The findings from this study offer valuable insights into the physical structure of iron-carbohydrate nanoparticles, a crucial step towards unraveling the intricate relationship between the structure and function of this widely used drug class in treating iron deficiency. Additionally, we developed and utilized the self-supervised machine learning workflow for the image analysis of iron-carbohydrate complexes, which might be further expanded into a useful characterization tool for comparability studies.