Arsenite induces testicular oxidative stress in vivo and in vitro leading to ferroptosis.

Ferroptosis is a newly identified form of cell death characterized by accumulation of intracellular iron and requirement of lipid peroxidation. However, whether arsenite triggers testicular cell death via ferroptosis remains unclear. In this study, after administrating of adult male mice with 0.5, 5 and 50 mg/L arsenite for six months via drinking water, the results showed that arsenite caused the pathological changes in mouse testis and significantly reduced the number of sperm. Mitochondrial injuries were observed as the major ultrastructural damages induced by arsenite, and these damages were accompanied by the apparent mitochondrial oxidative damage in the testis, manifested by accumulation of iron, production of reactive oxygen species and lipid peroxidation products. We also demonstrated that arsenite significantly activated ferroptosis-related signal pathways in the mouse testis. To further verify the results obtained in the animal model, GC-2spd cells were employed as the in vitro culture system. Consistently, the results revealed arsenite remarkably triggered the ferroptotic cell death in vitro, and inhibition of ferroptosis by ferrostatin-1 could attenuate this adverse effect in cells. These findings together indicate that arsenite can trigger oxidative stress thus leading to testicular cell death by ferroptosis, suggesting that inhibition of ferroptosis would be a potential strategy for treatment of arsenite-related male reproductive toxicity.

Meng P ，Zhang S ，Jiang X ，Cheng S ，Zhang J ，Cao X ，Qin X ，Zou Z ，Chen C ... -  《-》

Ferroptosis is newly characterized form of neuronal cell death in response to arsenite exposure.

Ferroptosis is a novel iron-dependent form of cell death implicated in brain pathology. However, whether arsenite is an inducer of ferroptosis in the neuron remains completely unknown. In this study, the seven-week-old healthy C57BL/6 J male mice were treated with environmental related doses (0.5, 5 and 50 mg/L) of arsenite for 6 months via drinking water, and the ferroptosis-related indicators were further determined. Our results demonstrated for the first time that, arsenite exposure significantly reduced the number of neuron and caused the pathological changes of mitochondria in the cerebral cortex of mice. We further revealed that arsenite induced ferroptotic cell death in neuron by accumulation of reactive oxygen species and lipid peroxidation products, disruption of Fe2+ homeostasis, depletion of glutathione and adenosine triphosphate, inhibition of cysteine/glutamate antiporter, activation of mitogen-activated protein kinases and mitochondrial voltage-dependent anion channels pathways, up-regulation of endoplasmic reticulum stress, all of which were involved in the process of ferroptosis. These findings were also verified in the cultured PC-12 cells by using ferropotosis inhibitor, desferoxamine. Taken together, our results not only reveal a novel mechanism that chronic arsenite exposure may trigger the new form of cell death, ferroptosis, but also shed a new light on a potential clue for the intervention and prevention against arsenite-related neurodegenerative diseases.

Tang Q ，Bai L ，Zou Z ，Meng P ，Xia Y ，Cheng S ，Mu S ，Zhou J ，Wang X ，Qin X ，Cao X ，Jiang X ，Chen C ... -  《-》

Induction of ferroptosis in response to graphene quantum dots through mitochondrial oxidative stress in microglia.

Wu T ，Liang X ，Liu X ，Li Y ，Wang Y ，Kong L ，Tang M ... -  《Particle and Fibre Toxicology》

Arsenite induces ferroptosis in the neuronal cells via activation of ferritinophagy.

Ferroptosis is a novel form of cell death that involves in the pathophysiological process of diverse brain diseases. However, how arsenite induces ferroptosis in the neuronal cells remains unsolved. In this study, by using in vitro and in vivo models, we demonstrated that arsenite was able to trigger ferroptosis in the neuronal cells. Exposure of arsenite for 6 months at 0.5, 5 and 50 mg/L arsenite via drinking water significantly reduced the number of neurons and caused the pathological changes in the mitochondria of hippocampus. Treatment of arsenite elevated the contents of lipid peroxidation products, disrupted the iron homeostasis, altered the expressions of ferroptosis-related proteins in the hippocampus and PC-12 cells. The results also showed that arsenite significantly decreased the expressions of ferritin and NCOA4, but sharply enhanced the level of autophagy marker LC3B, suggesting the activation of ferritinophagy by arsenite. Co-treatment of arsenite with ferroptosis inhibitor ferrostatin-1, or autophagy inhibitors 3-MA and BafA1, all remarkably attenuated the cytotoxic effects of arsenite. These findings not only present a novel mechanism that arsenite triggers ferroptosis in the neuronal cells via activation of ferritinophagy, but also indicate that regulating ferritinophagy to control iron level may provide a clue for prevention against arsenite neurotoxicity.

Xiao J ，Zhang S ，Tu B ，Jiang X ，Cheng S ，Tang Q ，Zhang J ，Qin X ，Wang B ，Zou Z ，Chen C ... -  《-》

PM2.5 induces ferroptosis in human endothelial cells through iron overload and redox imbalance.

PM2.5 is becoming a worldwide environmental problem, which profoundly endangers public health, thus progressively capturing public attention this decade. As a fragile target of PM2.5, the underlying mechanisms of endothelial cell damage are still obscure. According to the previous microarray data and signaling pathway analysis, a new form of cell death termed ferroptosis in the current study is proposed following PM2.5 exposure. In order to verify the vital role of ferroptosis in PM2.5-induced endothelial lesion and further understand the potential mechanism involved, intracellular iron content, ROS release and lipid peroxidation, as well as biomarkers of ferroptosis were detected, respectively. As a result, uptake of particles increases cellular iron content and ROS production. Meanwhile, GSH depletion, and the decrease of GSH-Px and NADPH play significant roles in PM2.5-induced endothelial cell ferroptosis. Moreover, significantly changed expression of TFRC, FTL and FTH1 hinted that dysfunction of iron uptake and storage is a major inducer of ferroptosis. Importantly, index monitored above can be partially rescued by lipid peroxidation inhibitor ferrostatin-1 and iron chelator deferoxamine mesylate, which mediated antiferroptosis activity mainly depends on the restoration of antioxidant activity and iron metabolism. In conclusion, our data basically show that PM2.5 enhances ferroptosis sensitivity with increased ferroptotic events in endothelial cells, in which iron overload, lipid peroxidation and redox imbalance act pivotal roles.

Wang Y ，Tang M 《-》