Gadodiamide Induced Autophagy and Apoptosis in Human Keratinocytes

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.

Metformin induces autophagy of cisplatin-resistant human gastric cancer cells in addition to apoptosis

Metformin has been used to treat cases of type 2 diabetes mellitus, and mounting studies have shown that metformin can act alone or in synergy with other anticancer agents to achieve anti-cancer efficacies on various types of tumors. However, the role of metformin in either inducing autophagy and cisplatin-resistance of human gastric cancer (GC) cells has never been examined. The study has established a cisplatin-resistant GC cell line and investigated the effects of metformin on inducing autophagy on it. The results demonstrated that treatment with metformin can concentration-dependently suppress the cell viability and cell confluence of cisplatin-resistant GC cells, while having no effects on human primary stomach epithelial cells (HPSEC). For the first time, we found that metformin can significantly increase the acidic vesicular organelles (AVO) level and decrease the acridine orange (AO) level spontaneously in the cisplatin-resistant GC cells. Thus, we further checked the other markers, Atg5, Atg12 and LC3-II, which showed that metformin indeed induced autophagy in the cisplatin-resistant GC cells. In addition, treatment of 3-Methyladenine (3-MA) can significantly rescue the metformin-induced autophagy. At the same time, metformin can induce the alterations of apoptosis-associated signal molecules, such as caspase-3 and caspase-7 activities. Overall, the pilot study provided evidence for metformin induced autophagy in addition to apoptosis, making it as an effective anticancer drug for the therapy of cisplatin-resistant GC. Killing the cisplatin-resistant GC cells with non-toxic metformin via both autophagy and apoptosis might extend its usefulness in our fighting with chemo-resistance of gastric cancer cells.

Protective Effects of Jujubosides on 6-OHDA-Induced Neurotoxicity in SH-SY5Y and SK-N-SH Cells

6-hydroxydopamine (6-OHDA) is used to induce oxidative damage in neuronal cells, which can serve as an experimental model of Parkinson’s disease (PD). Jujuboside A and B confer free radical scavenging effects but have never been examined for their neuroprotective effects, especially in PD; therefore, in this study, we aimed to investigate the feasibility of jujubosides as protectors of neurons against 6-OHDA and the underlying mechanisms. 6-OHDA-induced neurotoxicity in the human neuronal cell lines SH-SY5Y and SK-N-SH, was used to evaluate the protective effects of jujubosides. These findings indicated that jujuboside A and B were both capable of rescuing the 6-OHDA-induced loss of cell viability, activation of apoptosis, elevation of reactive oxygen species, and downregulation of the expression levels of superoxide dismutase, catalase, and glutathione peroxidase. In addition, jujuboside A and B can reverse a 6-OHDA-elevated Bax/Bcl-2 ratio, downregulate phosphorylated PI3K and AKT, and activate caspase-3, -7, and -9. These findings showed that jujubosides were capable of protecting both SH-SY5Y and SK-N-SH neuronal cells from 6-OHDA-induced toxicity via the rebalancing of the redox system, together with the resetting of the PI3K/AKT apoptotic signaling cascade. In conclusion, jujuboside may be a potential drug for PD prevention.