Background Exposure to benzo[a]pyrene (BaP) may impair lung function through various mechanisms; however, it remains uncertain whether BaP induces ferroptosis in lung tissue cells, resulting in lung function impairment. Objective To investigate the ferroptosis of lung tissue cells triggered by subchronic BaP exposure in mice and its correlation with lung injury, and to explore the function of ferroptosis in BaP-induced lung tissue damage. Method Seventy-two healthy 3-weeks-old male C57BL/6J mice were acclimatized for 1 week and then randomly divided into six groups: control group (corn oil 10 mL·kg⁻¹), low-dose BaP group (2.5 mg·kg⁻¹), medium-dose BaP group (5 mg·kg⁻¹), high-dose BaP group (10 mg·kg⁻¹), BaP+ferrostatin-1 (Fer-1) group (10 mg·kg⁻¹+1 mg·kg⁻¹), and Fer-1 group (1 mg·kg⁻¹), with 12 mice each group. Corn oil and BaP were administered via gavage every other day, followed by an intraperitoneal injection of Fer-1 the subsequent day, throughout a period of 90 d. Whole-body plethysmography was applied to detect lung function; hematoxylin-eosin staining (HE) and Masson staining were used to observe lung tissue injury and fibrosis; microscopy of alveolar epithelial cells was conducted to reveal mitochondrial morphology; biochemical assays were used to measure the content of tissue iron, malondialdehyde (MDA), and glutathione (GSH), as well as the activity of glutathione peroxidase (GSH-Px); Western blotting and real-time quantitative PCR (RT-qPCR) analyses were performed to reveal the protein and mRNA expression of ferroptosis markers. Results Compared to the control group, the high-dose BaP group showed a significant increase in expiration time (Te) (P<0.01), and a significant decrease in ratio rate of achieving peak expiratory flow (Rpef), tidal volume (TVb), peak inspiratory flow (PIF), minute volume (MVb), and peak expiratory flow (PEF) (P<0.05 or 0.01). Based on the results of HE and Masson staining, partial destruction of alveolar structures, thickening of alveolar walls, infiltration of inflammatory cells, significant thickening of tracheal walls and a large deposition of collagen fibers in lung tissue were observed in the medium- and high-dose BaP groups. By microscopy, the alveolar epithelial cells exposed to low-dose BaP showed condensed chromatin, and the mitochondria exposed to medium and high-dose BaP showed wrinkles, increased mitochondrial membrane density, and diminished mitochondrial cristae. Compared to the control group, in the medium- and high-dose BaP groups, the lung tissue iron content and the expression levels of ACSL4 protein and mRNA significantly elevated (P<0.01 or 0.05), while the mRNA expression level of SLC7A11 significantly decreased (P<0.05); in the high-dose BaP group, the MDA content, COX2 protein, and PTGS2 mRNA expression levels significantly increased (P<0.05 or 0.01), GSH content and GSH-Px activity, GPX4 protein and mRNA expression levels, and the expression level of SLC7A11 protein significantly decreased (P<0.01 or 0.05). The ferroptosis inhibitor Fer-1 markedly reversed respiratory function, morphology, mitochondrial alterations, and the aforementioned ferroptosis-related biochemical indicators. Conclusion Subchronic exposure to BaP can induce ferroptosis in mice lung tissue cells, resulting in compromised lung function.

AIM:To investigate the role of minocycline on glutamate uptake in the periventricular zone and its putative mechanism after hypoxic exposure in neonatal rats.METHODS: A model of hypoxic-ischemic brain damage (HIBD) was developed by putting postnatal 1 d rat pups in 5%O2 for 3.5 h.The glutamate level in periventricular zone was measured by liquid chromatography coupled with tandem mass spectrometry assay ( LC-MS/MS) after hypoxic exposure for 4 h and 1 d.The dynamic changes of glutamate transporters EAAT1, and EAAT2 during developmental period in periventricular zone were determined by Western blot.Moreover, the expression of EAAT1, EAAT2, Iba-1, IL-1β, TNF-αand TGF-β1 was also detected by Western blot after hypoxic exposure for 4 h and 1 d in that region.The effects of mino-cycline on all parameters mentioned above were tested after minocycline treatment at the same time points and in the same region.RESULTS:After hypoxic exposure, glutamate level was increased, but it was decreased after minocycline treat-ment.EAAT1 and EAAT2 kept a low expression level at the first postnatal week, but a predominant elevation was found at the end of the second postnatal week.The expression of EAAT1, EAAT2, Iba-1, IL-1βand TGF-β1 was increased at 1 d after hypoxic exposure.EAAT1 and TNF-αexpression was significantly up-regulated, while EAAT2 was down-regulated af-ter minocycline treatment.CONCLUSION: Minocycline inhibits the increase in the glutamate level after hypoxia in periventricular region of the neonatal rats.The mechanism may relate to the selective regulation of glutamate transporters, rather than the inhibition of neuroinflammation in periventricular zone.

OBJECTIVE: To investigate the effects of LCL161, a Smac mimetic, on the proliferation and apoptosis in hepatocellular carcinoma cells and the underlying mechanisms. 
 METHODS: The effect of LCL161 on the cell viability of HepG2 and SMMC7721 cells was measured by MTT assay. The effect of LCL161 at lower concentrations on the proliferation in hepatocellular carcinoma (HCC) cells was detected by colony formation assay. Apoptosis was assessed by flow cytometry with PI staining. The mitochondrial membrane potential was measured by JC-1 staining. The expression of PARP, p-Akt, cIAP1 and XIAP protein was analyzed by Western blot.
 RESULTS: LCL161 displayed notable antiproliferative activity on HCC cells at the concentrations of 1-16 μmol/L (P<0.01), with IC50 values of 4.3 and 4.9 μmol/L for HepG2 and SMMC7721 cells, respectively, after treatment for 48 h. LCL161 at lower concentrations obviously inhibited the colony formation of HCC cells. LCL161 induced significant apoptosis in HCC cells (P<0.01), and resulted in the apoptotic rate at (1.5±0.8)% or (1.8±0.6)% , (15.2±2.8)% or (12.2±2.4)%, (28.7±3.0)% or (22.4±2.7)%, (34.6±2.3)% or (30.2±2.4)% for HepG2 cells or SMMC7721 cells at the concentration of 0, 2, 4 or 8 μmol/L, respectively. The result of JC-1 staining indicated that the mitochondrial membrane potential of HCC cells was reduced by LCL161. In addition, LCL161 promoted the cleavage of PARP, down-regulated the protein expression of p-Akt, and degraded cIAP1.
 CONCLUSION LCL161 possesses significant anti-proliferative activity and pro-apoptotic action in HepG2 and SMMC7721 cells, which might be correlated with reduction in mitochondrial membrane potential, down-regulation of p-Akt and degradation of cIAP1.
Apoptosis ; drug effects ; Carcinoma, Hepatocellular ; drug therapy ; genetics ; pathology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cell Survival ; Down-Regulation ; Hep G2 Cells ; Humans ; Inhibitor of Apoptosis Proteins ; metabolism ; Liver Neoplasms ; Membrane Potential, Mitochondrial ; drug effects ; Proto-Oncogene Proteins c-akt ; genetics ; Thiazoles ; pharmacology ; Ubiquitin-Protein Ligases ; metabolism ; X-Linked Inhibitor of Apoptosis Protein