Deferoxamine Mitigates Ferroptosis and Inflammation in Hippocampal Neurons After Subarachnoid Hemorrhage by Activating the Nrf2/TXNRD1 Axis.

Ferroptosis is a distinct peroxidation-driven form of cell death tightly involved in subarachnoid hemorrhage (SAH). This study delved into the mechanism of deferoxamine (DFO, an iron chelator) in SAH-induced ferroptosis and inflammation. SAH mouse models were established by endovascular perforation method and injected intraperitoneally with DFO, or intraventricularly injected with the Nrf2 pathway inhibitor ML385 before SAH, followed by detection of neurological function, blood-brain barrier (BBB) permeability, and brain water content. Apoptotic level of hippocampal neurons, symbolic changes of ferroptosis, and levels of pro-inflammatory cytokines were assessed using TUNEL staining, Western blotting, colorimetry, and ELISA. The localization and expression of nuclear factor-erythroid 2-related factor 2 (Nrf2) were detected. HT22 cells were exposed to Hemin as in vitro SAH models and treated with FIN56 to induce ferroptosis, followed by evaluation of the effects of DFO on FIN56-treated HT22 cells. The regulation of Nrf2 in thioredoxin reductase 1 (TXNRD1) was analyzed by co-immunoprecipitation and Western blotting. Moreover, HT22 cells were treated with DFO and ML385 to identify the role of DFO in the Nrf2/TXNRD1 axis. DFO extenuated brain injury, and ferroptosis and inflammation in hippocampal neurons of SAH mice. Nrf2 localized at the CA1 region of hippocampal neurons, and DFO stimulated nuclear translocation of Nrf2 protein in hippocampal neurons of SAH mice. Additionally, DFO inhibited ferroptosis and inflammatory responses in FIN56-induced HT22 cells. Nrf2 positively regulated TXNRD1 protein expression. Indeed, DFO alleviated FIN56-induced ferroptosis and inflammation via activation of the Nrf2/TXNRD1 axis. DFO alleviated neurological deficits, BBB disruption, brain edema, and brain injury in mice after SAH by inhibiting hippocampal neuron ferroptosis via the Nrf2/TXNRD1 axis. DFO ameliorates SAH-induced ferroptosis and inflammatory responses in hippocampal neurons by activating the Nrf2/TXNRD1 axis.

Association between soluble neprilysin and diabetes: Findings from a prospective longitudinal study.

Background: The potential role of neprilysin (NEP) in glucose metabolism has been found by basic studies but lacks population evidence. The objective of this study was to examine the association between serum NEP and diabetes in Chinese adults. Methods: In a prospective longitudinal cohort study - the Gusu cohort (n=2,286, mean age: 52 years, 61.5% females), the cross-sectional, longitudinal, and prospective associations between serum NEP and diabetes were systemically examined by logistic regression adjusting for conventional risk factors. Serum NEP was measured at baseline using commercial ELISA assays. Fasting glucose was repeatedly measured 4 years apart. Results: The cross-sectional analysis found a positive association between serum NEP and fasting glucose at baseline (ß=0.08, P=0.004 for log-transformed NEP). This association persisted after controlling for the dynamic risk profiles during follow-up (ß=0.10, P=0.023 for log-transformed NEP). The prospective analysis found that a higher level of serum NEP at baseline was associated with a higher risk of diabetes during follow-up (OR=1.79, P=0.039 for log-transformed NEP). Conclusions: Serum NEP was not only associated with prevalent diabetes but also predicted the future risk of diabetes development in Chinese adults, independent of many behavioral and metabolic factors. Serum NEP may be a predictor and even a new therapeutic target for diabetes. However, the casualty and mechanisms of NEP in the development of diabetes require further investigation.

miR-1297 sensitizes glioma cells to temozolomide (TMZ) treatment through targeting adrenomedullin (ADM).

BACKGROUND: Gliomas account for about 80% of all malignant brain and other central nervous system (CNS) tumors. Temozolomide (TMZ) resistance represents a major treatment hurdle. Adrenomedullin (ADM) has been reported to induce glioblastoma cell growth. METHODS: Cell viability was measured using the CCK-8 assay. The apoptosis analysis was performed using the Annexin V-FITC Apoptosis Detection Kit. The mitochondrial membrane potential was determined by JC-1 staining. A nude mouse tumor assay was used to detect tumor formation. Hematoxylin and eosin (H&E) and immunohistochemical (IHC) staining were performed in tissue sections. Activation of Akt and Erk and expression of apoptosis-related proteins were determined by immunoblotting. RESULTS: ADM expression has been found upregulated in TMZ -resistant glioma samples based on bioinformatics and experimental analyses. Knocking down ADM in glioma cells enhanced the suppressive effects of TMZ on glioma cell viability, promotive effects on cell apoptosis, and inhibitory effects on mitochondrial membrane potential. Moreover, ADM knockdown also enhanced TMZ effects on Bax/Bcl-2, Akt phosphorylation, and Erk1/2 phosphorylation. Bioinformatics and experimental investigation indicated that miR-1297 directly targeted ADM and inhibited ADM expression. miR-1297 overexpression exerted similar effects to ADM knockdown on TMZ-treated glioma cells. More importantly, under TMZ treatment, inhibition of miR-1297 attenuated TMZ treatment on glioma cells; ADM knockdown partially attenuated the effects of miR-1297 inhibition on TMZ-treated glioma cells. CONCLUSIONS: miR-1297 sensitizes glioma cells to TMZ treatment through targeting ADM. The Bax/Bcl-2, Akt, and Erk1/2 signaling pathways, as well as mitochondrial functions might be involved.

Evaluating the efficacy and safety of percutaneous coronary intervention (PCI) versus the optimal drug therapy (ODT) for stable coronary heart disease: a systematic review and meta-analysis.

Background: Many studies have reported potential benefits of percutaneous coronary intervention (PCI) versus optimal drug therapy (ODT) for patients with stable coronary heart disease but with inconsistent results. To examine this, an explicit systematic review and meta-analysis was conducted to compared the clinical outcomes of PCI and ODT in these patients. Methods: The following terms were combined to search relative articles through databases PubMed, Cochrane Central Register of Controlled Trials, Embase, and Web of Science published from January 2010 to November 2021 according to Participants, Intervention, Control, Outcomes, Study (PICOS) criteria: "coronary heart disease", "stable coronary heart disease", "stable angina pectoris", "percutaneous coronary intervention", "PCI", "percutaneous transluminal coronary angioplasty", "drug therapy", "optimized drug treatment", and "optimized drug therapy". The meta-analysis was performed by RevMan 5.2, and the Cochrane risk of bias tool was used to evaluate the quality of the included studies. Results: A total of 12 articles were included in the final analysis. There were 4,288 cases of PCI patients and 4,261 cases of ODT patients. The results showed that, when comparing PCI with ODT, there was a significant difference in the probability of myocardial infarction [relative risk (RR) =0.63; 95% confidence intervals (CI): 0.45-0.90] and the patient mortality (RR =0.51; 95% CI: 0.40-0.64). However, there was no significant difference in the prevalence of stroke (RR =1.33; 95% CI: 0.82-2.17), revascularization (RR =0.86; 95% CI: 0.46-1.62) and patient quality of life (MD =10.44; 95% CI: -1.84 to 22.73). Performance bias and detection bias were all unclear in the included studies and should be warned. Discussion: Compared with ODT, PCI reduced the mortality and myocardial infarction rate of patients with CTO or severe coronary artery stenosis. However, the incidence of stroke, revascularization, and quality of life of patients were not significant different between PCI and ODT. Performance bias and detection bias should be cautioned.

Increased serum C1q/TNF-related protein 4 concentration in patients with acute coronary syndrome.

Accumulated evidence have revealed profound associations between C1q/TNF-related proteins (CTRPs) and coronary artery disease (CAD); yet, the relationship of CTRP4 to CAD has not been investigated. We examined the role of CTRP4 in CAD, and especially in acute coronary syndrome (ACS). METHODS: A total of 138 patients referred for coronary angiography were included in this study and were classified into 3 groups (ACS, CAD and control group). Comparisons regarding clinical data and CTRP4 concentration were performed among 3 groups. Weighted least-squares regression analysis was used to identify the independent predicting factors for CTRP4. RESULTS: Compared with either CAD (median 7.19 vs. 9.43, P < 0.05) or control group (median 7.22 vs. 9.43, P < 0.01), ACS group showed higher CTRP4 concentration. In addition, trend χ2 test revealed the presence of ACS increased with increased CTRP4 concentration (P = 0.010). Finally, in the weighted least-squares regression analysis, ACS was the only independent variable influencing CTRP4 concentration (ß- coefficient = 3.082, P = 0.004), even after adjusting for high-sensitivity C reactive protein (ß- coefficient = 3.050, P = 0.007). CONCLUSIONS: CTRP4 was associated with ACS; moreover, ACS was the independent factor in predicting CTRP4 concentration. The potentially important implications of CTRP4 in ACS may offer a novel insight into understanding the link between inflammation and ACS.

Acute cardiac complications and subclinical myocardial injuries associated with pheochromocytoma and paraganglioma.

BACKGROUND: Catecholamine excess arising from pheochromocytomas and paragangliomas (PPGLs) can cause a wide spectrum of cardiac manifestations, including acute cardiac complications (ACCs) and subclinical myocardial injuries (SMIs). In this study, we aimed to conduct a comprehensive analysis of ACCs and SMIs in a large cohort of patients with PPGLs. METHODS: We retrospectively analyzed the clinical data of consecutive patients with PPGLs admitted between January 2013 and July 2020 (n = 189). The prevalence of ACCs and SMIs and characteristics of patients identified with ACCs and SMIs were investigated. Moreover, comparisons were performed between patients with and without ACCs. RESULTS: Fourteen patients (7.4%) fulfilled the criteria for ACCs, including nine (4.8%) who presented with Takotsubo-like cardiomyopathy, four (2.1%) with heart failure with preserved ejection fraction, and finally one (0.5%) with catecholamine-induced cardiomyopathy. Compared to those without ACCs (n = 175), patients with ACCs had a higher prevalence of epinephrine-producing PPGLs (81.8% vs 33.9%, P = 0.006) and were more likely to show invasive behavior (61.5% vs 27.3%, P = 0.022) or hemorrhage/necrosis (53.9% vs 17.4%, P = 0.005) on histology. The apical sparing pattern (5/7, 71.4%) was the dominant impairment pattern of longitudinal strain (LS) for patients displaying Takotsubo-like cardiomyopathy. In patients without cardiac symptoms, a fairly high proportion (21/77, 27.3%) of patients who underwent screening for troponin and/or natriuretic peptide and/or echocardiography had SMIs. CONCLUSIONS: One in every fourteen PPGL patients presented with ACCs, and in the patients with Takotsubo-like cardiomyopathy, the apical sparing pattern was the primary impairment pattern of LS. Additionally, nearly one-third of patients without symptoms had SMIs. The diagnosis of PPGLs should be considered in patients with acute reversible cardiomyopathy, especially in those exhibiting an apical sparing pattern of LS.

Next-generation sequencing of microRNAs reveals a unique expression pattern in different types of pituitary adenomas.

Pituitary adenomas (PAs) are considered the most common intracranial tumor to cause serious morbidity because of dysregulated pituitary hormone secretions. Aberrant expression of microRNAs (miRNAs) is correlated with the development and function of the pituitary gland as well as the tumorigenesis of hypothalamic-pituitary axis-related pituitary tumors. In this study, we showed the differential expression patterns of miRNAs in NFPAs (nonfunctioning pituitary adenomas), GHPAs (growth hormone-secreting pituitary adenomas) and PRLPAs (prolactin-secreting pituitary adenomas) compared to those in three normal pituitary glands using the HiSeq 2000 sequencing system (Illumina). We validated miRNA expression using real-time quantitative polymerase chain reaction (RT-qPCR) analyses of samples from 73 patients (13 GHPAs, 42 NFPAs, and 18 PRLPAs) and 6 normal pituitary gland. We observed that miR-34c-3p was significantly downregulated in our PRLPA samples (p < 0.01), along with miR-34b-5p, miR-378 and miR-338-5p (all p < 0.05). In NFPAs, miR-493-5p was downregulated, and miR-181b-5p was significantly upregulated (p < 0.01). In GHPAs, miR-184 was significantly upregulated (p < 0.05). We observed that the tumor suppressive miR-124-3p was downregulated in both NFPAs and GHPAs. Taken together, we showed distinctive miRNA expression patterns in these three PAs, and these miRNA signatures in PA may have therapeutic potential as novel biomarkers for each type of PA.

MicroRNA-186 targets SKP2 to induce p27Kip1-mediated pituitary tumor cell cycle deregulation and modulate cell proliferation.

Pituitary tumors are usually benign but can occasionally exhibit hormonal and proliferative behaviors. Dysregulation of the G1/S restriction point largely contributes to the over-proliferation of pituitary tumor cells. F-box protein S-phase kinase-interacting protein-2 (SKP2) reportedly targets and inhibits the expression of p27Kip1, a well-known negative regulator of G1 cell cycle progression. In this study, SKP2 expression was found to be upregulated while p27Kip1 expression was determined to be downregulated in rat and human pituitary tumor cells. Furthermore, SKP2 knockdown induced upregulation of p27Kip1 and cell growth inhibition in rat and human pituitary tumor cells, while SKP2overexpression elicited opposite effects on p27Kip1 expression and cell growth. The expression of microRNA-186 (miR-186) was reported to be reduced in pituitary tumors. Online tools predicted SKP2 to be a direct downstream target of miR-186, which was further confirmed by luciferase reporter gene assays. Moreover, miR-186 could modulate the cell proliferation and p27Kip1-mediated cell cycle alternation of rat and human pituitary tumor cells through SKP2. As further confirmation of these findings, miR-186 and p27Kip1 expression were downregulated, while SKP2 expression was upregulated in human pituitary tumor tissue samples; thus, SKP2 expression negatively correlated with miR-186 and p27Kip1 expression. In contrast, miR-186 expression positively associated with p27Kip1 expression. Taken together, we discovered a novel mechanism by which miR-186/SKP2 axis modulates pituitary tumor cell proliferation through p27Kip1-mediated cell cycle alternation.

Deep Sequencing of Small RNAs in Blood of Patients with Brain Arteriovenous Malformations.

BACKGROUND: Deregulation of circulating microRNAs (miRNAs) is always associated with development and progression of human diseases. We aimed to assess whether patients with brain arteriovenous malformations (BAVMs) possess a distinct miRNA signature compared with healthy subjects. METHODS: Three patients with unruptured BAVMs and 3 normal control subjects were recruited as case and control groups. Peripheral blood was collected, and miRNA signature was obtained by next-generation sequencing, followed by comparative, functional, and network analyses. Quantitative reverse transcription polymerase chain reaction was performed to validate expression of specific miRNAs. RESULTS: Deep sequencing detected 246 differentially expressed miRNAs in blood samples of patients with BAVMs compared with normal control subjects. For the top 5 miRNAs, 946 target genes were predicted, and a BAVM-specific miRNA-target gene regulatory network was constructed. Functional annotation suggested that 15 of the predicted miRNA-targeted genes were involved in vascular endothelial growth factor signaling, in which 3 critical miRNAs were involved: miR-7-5p, miR-199a-5p, and miR-200b-3p. CONCLUSIONS: We explored the miRNA expression signature of BAVMs, which will provide an important foundation for future studies on the regulation of miRNAs involved in BAVMs.

Exome Sequencing Identifies LOXL2 Mutation as a Cause of Familial Intracranial Aneurysm.

BACKGROUND: Genetic risk factors can contribute to the etiology of intracranial aneurysms (IAs), and the genetic predisposition of IAs is largely unknown. Our study aimed to explore the role of rare variations in IA susceptibility. METHODS: Whole-exome sequencing (WES) was performed in a representative family with a history of multiple cases of IAs. WES variants were prioritized by various filtering strategies, including frequency, predicted pathogenicity, and functional prediction. Sanger sequencing also was performed in an additional 2 families and sporadic IA cases. RESULTS: After WES and filtering, 15 single-nucleotide variants and 3 insertion/deletions (indels) were prioritized in the family. Among them, we selected 5 candidate variants (located in DHRS3, OR2G3, LOXL2, FGL1, and KLC3) by considering known disease genes or ontology association with cardiovascular morphogenesis or other known diseases. Genotyping results revealed that only c.C133T/p.H45Y in exon 2 of LOXL2 gene was segregated fully with definite IA phenotypes in the family. Moreover, LOXL2 has been reported as a susceptibility gene for IAs. CONCLUSIONS: LOXL2 c.C133T is a pathogenic mutation that is responsible for a fraction of familial IAs.

The regulation of nitric oxide synthase isoform expression in mouse and human fallopian tubes: potential insights for ectopic pregnancy.

Nitric oxide (NO) is highly unstable and has a half-life of seconds in buffer solutions. It is synthesized by NO-synthase (NOS), which has been found to exist in the following three isoforms: neuro nitric oxide synthase (nNOS), inducible nitric oxide synthase (iNOS), and endothelial nitric oxide synthase (eNOS). NOS activity is localized in the reproductive tracts of many species, although direct evidence for NOS isoforms in the Fallopian tubes of mice is still lacking. In the present study, we investigated the expression and regulation of NOS isoforms in the mouse and human Fallopian tubes during the estrous and menstrual cycles, respectively. We also measured isoform expression in humans with ectopic pregnancy and in mice treated with lipopolysaccharide (LPS). Our results confirmed the presence of different NOS isoforms in the mouse and human Fallopian tubes during different stages of the estrous and menstrual cycles and showed that iNOS expression increased in the Fallopian tubes of women with ectopic pregnancy and in LPS-treated mice. Elevated iNOS activity might influence ovulation, cilia beats, contractility, and embryo transportation in such a manner as to increase the risk of ectopic pregnancy. This study has provided morphological and molecular evidence that NOS isoforms are present and active in the human and mouse Fallopian tubes and suggests that iNOS might play an important role in both the reproductive cycle and infection-induced ectopic pregnancies.

Aberrant alteration of vascular endothelial growth factor-family signaling in human tubal ectopic pregnancy: what is known and unknown?

More than 98% of ectopic pregnancies occur in the Fallopian tube. Because many facets of tubal ectopic pregnancy remain unclear, prediction, prevention and treatment of tubal ectopic pregnancy are still a major clinical challenge. Compelling evidence suggests that angiogenic growth factors are involved in normal and abnormal implantation. While acknowledging the importance of an intrauterine pregnancy requires the development of a local blood supply and angiogenesis, we hypothesize that the hypoxic- and estrogen-dependent regulation of vascular endothelial growth factor/placental growth factor expression, secretion, and signaling pathways that are possibly involved in the pathophysiology of tubal ectopic pregnancy. Our hypothesis may also lead to a new therapeutic strategy for women with tubal ectopic pregnancy.