PKCδ modulates SP1 mediated mitochondrial autophagy to exacerbate diacetylmorphine-induced ferroptosis in neurons.

Diacetylmorphine (DA) is widely implicated in neuronal injury; however, the underlying mechanisms remain unclear. We investigated the role of iron metamorphosis in DA-induced neurotoxicity using Sprague-Dawley rats and PC12 and SH-SY5Y cells. Tandem mass tag proteomics analysis showed that the upregulation of protein kinase C delta (PKCδ) and iron metabolism-related protein transferrin receptor (TFRC) significantly the enriched iron metabolism pathway. Subsequent experiments showed that DA exposure significantly upregulated PKCδ in PC12 cells, which increased the nuclear translocation of specificity protein 1 (SP1), and the intracellular free iron and lipid peroxide levels. In addition, silencing of PKCδ in rats improved behaviour and restored the expression level of glutathione peroxidase 4 (GPX4). In addition, DA exposure activated mitochondrial autophagy in PC12 cells, leading to a decrease in the mitochondrial membrane potential, accumulation of reactive oxygen species (ROS), elevation of LC3 (which plays a key role in autophagy), and a decrease in p62 expression. Following the inhibition of autophagy, the mitochondrial membrane potential and ROS were restored, as was the expression of voltage-dependent anion channel 1 (VDAC1) and GPX4. In conclusion, the present study suggests that PKCδ regulates SP1, further exacerbating DA-induced neuronal ferroptosis. Therefore, inhibition of PKCδ and mitochondrial autophagy or ferroptosis may be a key therapeutic target to ameliorate neurotoxicity following DA exposure.

Zhuang M ，Zhu S ，Su L ，Liu L ，Ji M ，Dai C ，Liu J ，Zhang W ，Pu H ... -  《-》

Ferroptosis contributes to lead-induced cochlear spiral ganglion neurons injury.

Huang H ，Mei L ，Wang L ，Bai Y ，Gao K ，Song J ，Jiang M ，Chen Y ，Zhang S ，Pang B ，He Y ，Wu X ... -  《-》

Lycium barbarum polysaccharide alleviates ferroptosis in Sertoli cells through NRF2/SLC7A11/GPX4 pathway and ameliorates DEHP-induced male reproductive damage in mice.

Di-(2-ethylhexyl)phthalate (DEHP) is a common plasticizer that has been shown to significantly negatively affect male reproductive health. On the other hand, Lycium barbarum polysaccharide (LBP) has been shown to improve reproductive function. Therefore, we hypothesized that LBP may ameliorate DEHP-induced male reproductive damage. Herein, we found that LBP could alleviate DEHP-induced testicular damage and sperm abnormalities. Furthermore, histomorphological analysis of mice testis revealed that LBP primarily ameliorated the DEHP-induced male reproductive damage by targeting Sertoli cells. Moreover, the detection of the function-related genes of Sertoli cells confirmed this finding. The serum of mice in the Control, DEHP, and DEHP+LBP groups was analyzed using non-targeted metabolomics to further elucidate the mechanism of action of LBP in improving DEHP-induced male reproductive damage. According to the results, the differential metabolites were mainly enriched in the glutamate metabolism pathway, implying that LBP may alleviate the ferroptosis-related DEHP-induced testicular injury. Related ferroptosis markers were also found in mice testis. These findings collectively suggest that LBP may ameliorate DEHP-induced testicular injury via alleviating ferroptosis in Sertoli cells. To clarify the specific mechanism, we constructed a cell model in vitro by treating TM4 cells (the Sertoli cell line) with LBP and MEHP (the in vivo DEHP metabolite). Our findings revealed that LBP can improve the function of DEHP-affected Sertoli cells. Furthermore, the analysis of lipid peroxidation, Fe2+ content, and ferroptosis-related protein expressions demonstrated that LBP could ameliorate MEHP-induced ferroptosis in TM4 cells. To clarify the specific mechanism, glutamate metabolism-related proteins involved in the ferroptosis pathway were detected. According to the results, there were significant changes in the expression of NRF2, SLC7A11 and GPX4 proteins, which are involved in the ferroptosis glutamate metabolism pathway. Furthermore, supplementation of NRF2, SLC7A11, and GPX4 inhibitors (ML385, Erastin, and RSL3, respectively) blocked the therapeutic effect of LBP in alleviating MEHP-induced ferroptosis in TM4 cells, implying that LBP could also ameliorate MEHP-induced ferroptosis via the NRF2/SLC7A11/GPX4 pathway. In summary, these findings show that LBP can alleviate DEHP/MEHP-induced ferroptosis through the NRF2/SLC7A11/GPX4 pathway, ameliorating Sertoli cell dysfunction and improving the DEHP-induced male reproductive damage. Therefore, the clinical administration of LBP could be an effective strategy for preventing DEHP-induced male reproductive injury.

Yang H ，Ding L ，Xu B ，Zhang Z ，Dai W ，He T ，Liu L ，Du X ，Fu X ... -  《-》

Ophiopogon japonicus polysaccharide reduces doxorubicin-induced myocardial ferroptosis injury by activating Nrf2/GPX4 signaling and alleviating iron accumulation.

Chen Y ，Ma L ，Yan Y ，Wang X ，Cao L ，Li Y ，Li M ... -  《-》

Caveolin-1 ameliorates hepatic injury in non-alcoholic fatty liver disease by inhibiting ferroptosis via the NOX4/ROS/GPX4 pathway.

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease globally, with a complex and contentious pathogenesis. Caveolin-1 (CAV1) is an important regulator of liver function and can mitigate liver injury by scavenging reactive oxygen species (ROS). Evidence suggests that NOX4 is a source of ROS production, that oxidative stress and ferroptosis are closely related, and that both are involved in the onset and progression of NAFLD. However, whether CAV1 attenuates liver injury in NAFLD caused by high-fat diet via the NOX4/ROS/GPX4 pathway remains unclear. An in vivo fatty liver model was established by feeding mice with a high-fat diet for 16 weeks. In addition, an in vitro fatty liver model was established by incubating AML-12 cells with free fatty acids for 24 h using an in vitro culture method. In our study, it was observed that a high-fat diet induces mitochondrial damage and worsens oxidative stress in NAFLD. This diet also hinders GPX4 expression, leading to an escalation of ferroptosis and lipid accumulation. To counteract these effects, intraperitoneal administration of CSD peptide in mice attenuated the high-fat diet-induced liver mitochondrial damage and ferroptosis. Likewise, overexpression of CAV1 resulted in an increase in GPX4 expression and a reduction in levels of ROS-mediated iron metamorphosis, thus mitigating the progression of the disease. However, the effects of CAV1 on GPX4-mediated ferroptosis and lipid deposition could be reversed by CAV1 small interfering RNA (SiRNA). Finally, NOX4 inhibitor (GLX351322) treatment increased CAV1 siRNA-mediated GPX4 expression and decreased the level of ROS-mediated ferroptosis. These findings suggest a potential mechanism underlying the protective role of CAV1 against high-fat diet-induced hepatotoxicity in NAFLD, shedding new light on the interplay between CAV1, GPX4, and ferroptosis in liver pathology.

Wu S ，Guo N ，Xu H ，Li Y ，Sun T ，Jiang X ，Fu D ，You T ，Diao S ，Huang Y ，Hu C ... -  《-》