Ferroptosis has recently emerged as an iron-dependent form of nonapoptotic cell death, which is also a regulated necrosis process and a response to tumor suppression. However, whether ferroptosis is involved in ulcerative colitis (UC) is unknown. The aims of this study were to investigate whether the ferroptosis is involved in UC, particularly intestinal epithelial cell (IEC) death, and to analyze the effect of the nuclear factor kappa Bp65 subunit (NF-κBp65) on ferroptosis. The gene expression of ferroptosis-related proteins was assessed in intestinal mucosal samples from human UC. The experimental model of UC was induced with dextran sulfate sodium (DSS). Ferroptosis of IECs was evaluated, the effect of NF-κBp65 on ferroptosis was analyzed by using IEC-specific NF-κBp65-deleted mice (p65IEC-KO), and the ferroptosis signaling pathway was investigated in vitro and in vivo. The results showed that ferroptosis was significantly induced in the IECs from UC patients and mice with colitis, and the ferroptosis was mediated by endoplasmic reticulum (ER) stress signaling. The specific deletion of IEC NF-κBp65 clearly upregulated ferroptosis and exacerbated colitis, and the result showed that phosphorylated-NF-κBp65 significantly inhibited ER stress signaling by directly binding eukaryotic initiation factor 2α. These data indicate that ferroptosis contributes to UC via ER stress-mediated IEC cell death, and that NF-κBp65 phosphorylation suppresses ER stress-mediated IEC ferroptosis to alleviate UC. The results suggest that ferroptosis involves in IEC death in UC, NF-κBp65 play a critical role in the ferroptotic inhibition, and ferroptosis is a potential therapeutic target for UC.
Alzheimer’s disease (AD) is a common neurodegenerative disorder with progressive cognitive impairment in the elderly. Beta-amyloid (Aβ) formation and its accumulation in the brain constitute one of the pathological hallmarks of AD. Until now, how to modulate Aβ formation in hippocampal neurons remains a big challenge. Herein, we investigated whether the exosomal transfer of microRNA (miR) relates to amyloid pathology in the recipient neuron cells. We isolated circulating small extracellular vesicles (sEVs) from AD patients and healthy controls, determined the miR-342-5p level in the sEVs by RT-PCR, and evaluated its diagnostic performance in AD. Then, we took advantage of biomolecular assays to estimate the role of miR-342-5p in modulating the amyloid pathway, including amyloid precursor protein (APP), beta-site APP cleaving enzyme 1 (BACE1), and Aβ42. Furthermore, we subjected HT22 cells to the sEVs from the hippocampal tissues of transgenic APP mice (Exo-APP) or C57BL/6 littermates (Exo-CTL), and the Exo-APP enriched with miR-342-5p mimics or the control to assess the effect of the sEVs’ delivery of miR-342-5p on Aβ formation. We observed a lower level of miR-342-5p in the circulating sEVs from AD patients compared with healthy controls. MiR-342-5p participated in Aβ formation by modulating BACE1 expression, specifically binding its 3′-untranslated region (UTR) sequence. Exo-APP distinctly promoted Aβ42 formation in the recipient cells compared to Exo-CTL. Intriguingly, miR-342-5p enrichment in Exo-APP ameliorated amyloid pathology in the recipient cells. Our study indicated that miR-342-5p was dysregulated in human circulating sEVs from AD patients; sEV transfer of miR-342-5p ameliorates Aβ formation by modulating BACE1 expression. These findings highlight the promising potential of exosomal miRNAs in AD clinical therapy.
Introduction Based on the available data on ovarian cancer during pregnancy, we performed a review and meta-analysis to evaluate the efficacy and safety of platinum-based chemotherapy against ovarian cancer during pregnancy. Methods We systematically searched three databases including the PubMed, Embase, and Cochrane Library databases for articles published from January 1986 to December 2020 using the following terms: “ovarian tumors OR ovarian carcinoma OR adnexal masses OR ovarian cancer” AND “pregnancy” AND “chemotherapy.” Two authors (Yaping Pei and Yuanfeng Gou) independently searched the literature and extracted data from each eligible study. The outcome measures were overall survival (OS) and progression-free survival (PFS). The OS and PFS of all patients were estimated by Kaplan–Meier survival curves and log-rank tests. Results A total of 43 studies including 55 cases of ovarian cancer during pregnancy were selected. Forty-eight patients were comprehensively staged using the International Federation of Gynecology and Obstetrics (FIGO) staging system. Twenty-six of the 48 patients (54.17%) were diagnosed with early-stage disease, while the remaining had advanced stages (II, III, and IV). The mean age at diagnosis was 29.31 years. The majority of patients in this meta-analysis were diagnosed at a mean gestational age of 16.05 weeks. The mean GA at chemotherapy administration was 17.42 weeks. Overall, 55 women gave birth to 56 newborns, including a pair of twins. At the end of follow-up (median 10 months, range 0–73 months), all the children were healthy, except for one child who died 5 days after delivery due to a congenital abnormality. During 2–204 months of follow-up, there were five cases of recurrence, with no evidence of recurrence in the remaining cases. Unfortunately, one patient died 29 months after diagnosis. Neither median overall survival nor median progression-free survival was obtained. Conclusion Platinum-based chemotherapy may be a good choice for pregnant women with ovarian cancer who want to continue their pregnancy.