In VitroToxicological Assessment of Gadodiamide in Normal Brain SVG P12 Cells

Abstract

Background/Aim: Magnetic resonance imaging (MRI) is a technique for evaluating patients with primary and metastatic tumors. The contrast agents improve the diagnostic accuracy of MRI. Large quantities of a contrast agent must be administrated into the patient to obtain useful images, which leads to cell injury. Gadolinium has been reported to cause central lobular necrosis of the liver and nephrogenic systemic fibrosis. However, the toxicity caused on brain tissue is uncertain. Materials and Methods: This study mainly aimed on the in vitro study of high concentration (2 and 5-fold of normal concentration) gadolinium-based contrast agents (GBCAs), gadodiamide (Omniscan ® ), on normal brain glial SVG P12 cells. MTT assay, DAPI staining, immunofluorescent staining, LysoTracker Red staining, and western blotting analysis were applied on the cells. Results: The viability of gadodiamide (1.3, 2.6, 5.2, 13 and 26 mM)-treated SVG P12 cells was significantly reduced after 24 h of incubation. Gadodiamide caused significant autophagic flux at 2.6, 5.2 and 13.0 mM as seen by acridine orange (AO) staining, LC-3-GFP and LysoTracker Red staining. The expression levels of autophagy-related proteins such as beclin-1, ATG-5, ATG-14 and LC-3 II were up-regulated after 24 h of gadodiamide incubation. Autophagy inhibitors including 3-methyladenine (3-MA), chloroquine (CQ) and bafilomycin A1 (Baf) significantly alleviated the autophagic cell death effect of gadodiamide on normal brain glial SVG P12 cells. Gadodiamide induced significant apoptotic effects at 5.2 mM and 13.0 mM as seen by DAPI staining and the pan-caspase inhibitor significantly alleviated the apoptotic effect. Gadodiamide at 5.2 mM and 13.0 mM inhibited antiapoptotic protein expression levels of Bcl-2 and Bcl-XL, while promoted pro-apoptotic protein expression levels of Bax, BAD, cytochrome c, Apaf-1, cleaved-caspase-9 and cleaved-caspase-3. Conclusion: Normal brain glial SVG P12 cells treated with high concentrations of gadodiamide can undergo autophagy and apoptosis.Magnetic resonance imaging (MRI) is a non-invasive technique used to produce detailed images of internal structure in the human body and diagnose medical conditions. The density of adjacent organs is similar. Therefore, it is impossible to distinguish the shape, location 2621 This article is freely accessible online.

Gadodiamide Induced Autophagy and Apoptosis in Human Keratinocytes

“…However, the detailed mechanism remains unclear. It was hypothesized that the cytochrome c that is released from the mitochondria may bind to Apaf-1, which activates caspase cascade signalling (23,26). In the current study, we only provide evidence that cleaved-caspase-3 (Figure 5B), together with its activity (Figure 5C), is involved in gadodiamide-induced cytotoxicity.…”

“…Gadolinium has been reported to cause central lobular necrosis in the liver and NSF in the kidney (22). In our previous studies, we provided evidence that gadodiamide can induce cell death in normal brain glial SVG P12 cells (10,23). High levels of gadodiamide (with the same dosage used in the current study) may induce significant cytotoxicity in the brain, although gadodiamide has been proven by the FDA to be applied to the central nervous system (6,24).…”

“…To date, NSF seems to be the most severe symptom of gadodiamide retention in body tissues. Gadolinium metal ions are replaced by a contrast agent compound (transmetalation) and free gadolinium ions are deposited in various tissues, such as the skin, leading to fibrosis (23,25). However, the detailed mechanisms underlying skin toxicity have not yet been elucidated.…”

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

“…According to the gathered data, several signaling pathways have been implicated in Gd (III) mechanisms of toxicity, such as MAPK/ERK (mitogen-activated protein kinase/extracellular signal-regulated kinase), PI3K/Akt (phosphoinositide-3-kinase/protein kinase B), and EGFR (epidermal growth factor receptor) signaling [26,54,55,71,84,87,89,90,93], suggesting that Gd (III) interferes with the transduction of molecules involved in the regulation of inflammatory processes, and in cell metabolism, proliferation, growth, and survival. Upregulation of inflammation, oxidative stress, and apoptosis were highlighted as potential mechanisms of Gd (III) cytotoxicity [25,30,34,[38][39][40]42,[60][61][62]64,66,70,76,84,86,91,99,101,102,111,113]. It has been reported that exposure to Gd (III) or GBCAs may induce the expression of several profibrotic chemokines and cytokines, and alter cell growth [11,41,54,59,68,69,72,77,88,89,95,…”

“…Besides lipid peroxidation and ROS production, Gd (III) prompted the formation of autophagic vesicles, also revealing apoptotic and necrotic potential [42,110], pointing towards a multitude of cell death pathways being activated. Indeed, a decrease in cell viability, an increase in cell death through apoptosis, and autophagic activation have been associated with Gd (III) toxicity [10,30,34,40,[46][47][48]51,58,60,64,70,99,113]. Mitochondrial dysfunction [38,42,51,91,108,109] and suppressing mitochondria membrane potential [62,101] were also described.…”