Cellular and molecular pathways underlying the nephrotoxicity of gadolinium

Gadoteric Acid and Gadolinium: Exploring Short- and Long-Term Effects on Healthy Animals

Regarding the safety of gadolinium (Gd (III))-based contrast agents, we aimed to evaluate the short- and long-term effects following a single exposure to gadoteric acid (DOTA) or to free Gd (III) using animal models. Biomarkers of kidney injury, inflammation, iron metabolism, dyslipidemia, hepatic and hematologic disturbances and kidney histopathological and differential gene expression (DGE) analyses were evaluated. In the short-term study, compared to the controls, exposure to Gd (III) was associated with higher inflammation; changes in lipid, iron and hepatic metabolisms; hematological alterations; and kidney damage. Exposure to DOTA revealed changes in hematological, lipid and hepatic biomarkers. In the long-term study, compared to the controls, exposure to Gd (III) or to DOTA showed much fewer changes than the short-term exposure. Comparing the kidney gene expression of Gd (III) or DOTA exposure versus the control, we found clearly different DGE patterns and a lower number of differently expressed genes in the long-term study, for both compounds. Our data show that a single-dose exposure to these compounds induces several short-term changes which over time return to normal or are sustained, although with less severity, especially in the case of DOTA.

FeCl3 and GdCl3 solutions as superfast relaxation modifiers for agarose gel: a quantitative analysis

OBJECT

This study aimed to evaluate the relaxivity and uniformity of agarose gel phantoms added with relaxation modifiers. It is hypothesized that the modifiers could manipulate the T1 and T2 relaxations as well as the signal uniformity.

MATERIALS AND METHODS

Twenty agarose gel phantoms with different GdCl₃ and FeCl₃ volume fractions were prepared. The phantoms were scanned using a 3-T scanner implementing a turbo spin echo sequence to acquire T1 and T2 images. The SNR of the images were computed using Image-J software from 1, 3, and 25 regions-of-interest (ROIs) and were inverted as T1 and T2 curves.

RESULTS

With the increase in relaxation modifier content, T1 SNR increased at a faster rate at very short TR and reached saturation at TR well below 400 ms. Agarose gel phantoms containing GdCl3 showed a higher saturation value as compared to phantoms containing FeCl3. For T2 SNR, differences between plots are observed at low TE. As TE gets larger, the SNR between plots is incomparable. The SNR for both groups was uniform among 1, 3, and 25 ROIs.

DISCUSSIONS

It can be concluded that GdCl₃ and FeCl₃ solutions can be used as effective relaxation modifiers to reduce T1 but not T2 relaxation times.

Cannabidivarin and cannabigerol induce unfolded protein response and angiogenesis dysregulation in placental trophoblast HTR-8/SVneo cells

Cannabidivarin (CBDV) and cannabigerol (CBG) are minor phytocannabinoids from Cannabis sativa, whose health benefits have been reported. However, studies about the impact of these cannabinoids on fundamental cellular processes in placentation are scarce. Placental development involves physiological endoplasmic reticulum (ER) stress, however when exacerbated it can lead to altered angiogenesis and pregnancy disorders, such as intrauterine growth restriction and preeclampsia. In this work, the effects of CBDV and CBG (1-10 µM) on placental extravillous trophoblasts were studied, using the in vitro model HTR-8/SVneo cells. Both cannabinoids induced anti-proliferative effects and reactive oxygen/nitrogen species generation, which was dependent on transient receptor potential vanilloid 1 (TRPV1) activation. Moreover, CBDV and CBG significantly upregulated, in a TRPV-1 dependent manner, the gene expression of HSPA5/Glucose-regulated protein 78 (GRP78/BiP), a critical chaperone involved in ER stress and unfolded protein response (UPR) activation. Nevertheless, the UPR pathways were differentially activated. Both cannabinoids were able to recruit the IRE branch, while only CBDV enhanced the expression of downstream effectors of the PERK pathway, namely p-eIF2α, ATF4 and CHOP. It also augmented the activity of the apoptotic initiator caspases-8 and -9, though the effector caspases-3/-7 were not activated. TRB3 expression was increased by CBDV, which may hinder apoptosis termination. Moreover, both compounds upregulated the mRNA levels of the angiogenic factors VEGFA, PGF and sFLT1, and disrupted the endothelial-like behavior of HTR-8/SVneo cells, by reducing tube formation. Thus, CBDV and CBG treatment interferes with EVTs functions and may have a negative impact in placentation and in pregnancy outcome.

Toxicity Mechanisms of Gadolinium and Gadolinium-Based Contrast Agents-A Review

Gadolinium-based contrast agents (GBCAs) have been used for more than 30 years to improve magnetic resonance imaging, a crucial tool for medical diagnosis and treatment monitoring across multiple clinical settings. Studies have shown that exposure to GBCAs is associated with gadolinium release and tissue deposition that may cause short- and long-term toxicity in several organs, including the kidney, the main excretion organ of most GBCAs. Considering the increasing prevalence of chronic kidney disease worldwide and that most of the complications following GBCA exposure are associated with renal dysfunction, the mechanisms underlying GBCA toxicity, especially renal toxicity, are particularly important. A better understanding of the gadolinium mechanisms of toxicity may contribute to clarify the safety and/or potential risks associated with the use of GBCAs. In this work, a review of the recent literature concerning gadolinium and GBCA mechanisms of toxicity was performed.

Applications of metal-phenolic networks in nanomedicine: a review

The exploration of nanomaterials is beneficial for the development of nanomedicine and human medical treatment. Metal-phenolic networks (MPNs) have been introduced as a nanoplatform for versatile functional hybrid nanomaterials and have attracted extensive attention due to their simple preparation, excellent properties and promising medical application prospects. This review presents an overview of recent synthesis methods for MPNs, their unique biomedical properties and the research progress in their application in disease detection and treatment. First, the synthesis methods of MPNs are summarised, and then the advantages and applicability of each assembly method are emphasised. The various functions exhibited by MPNs in biomedical applications are then introduced. Finally, the latest research progress in MPN-based nanoplatforms in the biomedical field is discussed, and their future research and application are investigated.