Wild-type Group Research Articles

The clinical impact of EGFR alterations in elderly glioblastoma patients: results from a real-life cohort.

The incidence of glioblastoma in the elderly population is increasing as the worldwide population ages. The differential and poorer survival in the elderly population compared to younger patients is partially explained. The present study aimed to investigate the clinical impact of epidermal growth factor receptor EGFR-altered glioblastoma in a real-life elderly glioblastoma population. A bicentric and retrospective study was conducted. Patients were 70years or older and suffering from histomolecularly confirmed glioblastoma. Single nucleotide variants (SNV), amplification, or chromosome 7 polysomy were sought. The primary endpoint was the comparison of overall survival (OS) in patients with or without EGFR alteration. Secondary objectives were to determine other clinical parameters correlated with EGFR alteration status. Seventy-three patients were analyzed: 41.1% had at least one EGFR alteration. The presence of EGFR alteration did not impact overall survival: HR 0.97 [0.6-1.57], p = 0.9; the median overall survival was 6.5months [5.3-9.3] in the EGFR-altered group versus 7months [4.5-10] in the EGFR wild-type group, p = 0.75. In multivariate analysis, tumor resection was associated with a significant overall survival improvement: the median OS in the resected group (n = 20) was 11months [95% CI 7.8-22] versus a median OS of 5.5months [4.6-7.8] in the unresected group (n = 53), without correlation to EGFR alteration status. In the modern era of molecular characterization and improved treatment modalities, the presence of at least one EGFR alteration did not influence survival outcomes in an elderly population of glioblastoma patients.

Humanin-G Ameliorates Hemorrhage-Induced Acute Lung Injury in Mice Through AMPKα1-Dependent and -Independent Mechanisms

Background/Objectives: The severity of acute lung injury is significantly impacted by age and sex in patients with hemorrhagic shock. AMP-activated protein kinase (AMPK) is a crucial regulator of energy metabolism but its activity declines with aging. Humanin is a mitochondrial peptide that exerts cytoprotective effects in response to oxidative stressors and is associated with longevity. Using a mouse model of hemorrhagic shock that mimics the clinical condition of adult patients, we investigated whether treatment with a humanin analog, humanin-G, mitigates lung injury and whether its mechanisms of action are dependent on the catalytic AMPKα1 subunit activation. Methods: Male and female AMPKα1 wild-type (WT) and knock-out (KO) mice (8–13 months old) were subjected to hemorrhagic shock by blood withdrawal, followed by resuscitation with shed blood and lactated Ringer’s solution. The mice were treated with PEGylated humanin-G or vehicle and euthanized 3 h post-resuscitation. Results: Sex- and genotype-related differences were observed after hemorrhagic shock as lung neutrophil infiltration was more pronounced in the male AMPKα1 WT mice than the female WT mice; also, the male AMPKα1 KO mice experienced a significant decline in mean arterial blood pressure when compared to the male WT mice after resuscitation. The scores of histological lung injury were similarly elevated in all the male and female AMPKα1 WT and KO mice when compared to the control mice. At molecular analysis, acute lung injury was associated with the downregulation of AMPKα1/α2 catalytic subunits in the WT mice, whereas an increased activation of the signal transducer and activator of transcription-3 (STAT3) was observed in all the vehicle-treated groups. The in vivo administration of humanin-G ameliorated histological lung damage in all the groups of animals and ameliorated mean arterial blood pressure in the male AMPKα1 KO mice. The in vivo administration of humanin-G lowered lung neutrophil infiltration in the male and female AMPKα1 WT mice only but not in the KO mice. The beneficial results of humanin-G correlated with the lung cytosolic and nuclear activation of AMPKα in the male and female AMPKα1 WT groups, whereas STAT3 activation was not modified. Conclusions: In adult age, hemorrhage-induced acute lung injury manifests with sex-dependent characteristics. Humanin-G has therapeutic potential and the AMPKα1subunit is an important requisite for its inhibitory effects on lung leucosequestration, but not for the amelioration of lung alveolar structure or the hemodynamic effects of the peptide.

Abstract B073: Leveraging micronuclei DNA from erythrocytes for early detection of hepatocellular carcinoma

Abstract Background: Hepatocellular carcinoma (HCC) is the most common form of liver cancer and accounts for ∼90% of cases globally. Detection of early-stage HCC is vital as it allows for potentially curative treatment, yet remains a significant challenge. Micronuclei (MN) are a hallmark of genomic instability. An increased frequency of MN is commonly observed in tumor cells as well as other somatic cells, including erythrocytes, in cancer patients. Here, we have established a technique (WO2021/228246 A1), for the isolation and analysis of micronuclei DNA (MN-DNA) in erythrocytes from peripheral blood. Significant changes in read densities at specific genomic locations within MN-DNA were identified in patients, termed as tumor- associated MN-DNA (taMN-DNA) features. This study evaluates the potential of these taMN- DNA features for early-stage HCC detection across human and murine model. Methods: To explore the potential of MN-DNA in cancer detection, we first collected 1-2 mL of whole blood from HDs (N = 53) and HCC patients (N = 53). MN-DNA was isolated and purified from erythrocytes, followed by whole-genome sequencing. Participants were randomly divided into training, test cohorts in an 8:2 ratio. We applied machine learning algorithms to leverage these features for cancer detection in the human model. Additionally, to investigate the formation of taMN-DNA features, we employed a well-established mouse model that mimics HCC development. Mice were injected with the genotoxic agent diethylnitrosamine (DEN) 2 weeks after birth, and developed malignant macroscopic liver nodules at approximately 40 weeks of age. Results: In the human cohort, we enrolled 106 participants, with more than half of the HCC cases were diagnosed at early-stage (stage 0-II). The cancer detection model utilizing taMN- DNA features achieved an overall accuracy of 86.3%, with a sensitivity of 81.8% and specificity of 90.9%. For early-stage, the model demonstrated sensitivities of 54.5% at a specificity of 90.9%. In the DEN-induced HCC mouse model, unsupervised hierarchical clustering based on these selected taMN-DNA features clearly separated WT and tumor mice into two distinct groups. Notably, mice that were not tumorigenic at 36 weeks post-treatment in the DEN-treated group fell into the WT group when classified by the same taMN-DNA features, indicating that the formation of taMN-DNA signatures is associated with the presence of tumors specifically. Conclusions: This pilot study highlights the potential of MN-DNA as a promising tool for early HCC detection. Leveraging these taMN-DNA features can accurately distinguish early-stage HCC patients from HDs with high sensitivity. In both human and murine models, there is a significant relationship between these signatures and tumor presence, suggesting that taMN- DNA features might reflect the diseased state across mammalian species. Research sponsor: Timing Biotech. Citation Format: Hui Lin, Haobo Sun, Xingyun Yao, Xiaoxiao Fan, Fei Meng, Honghao Liang, Xiaofei Gao. Leveraging micronuclei DNA from erythrocytes for early detection of hepatocellular carcinoma [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr B073.

Complete inhibition of liver acetyl-CoA carboxylase activity is required to exacerbate liver tumorigenesis in mice treated with diethylnitrosamine.

The metabolic pathway of de novo lipogenesis (DNL) is upregulated in fatty liver disease and liver cancer. Inhibitors of DNL are in development for the treatment of these disorders; however, our previous study showed that blocking DNL unexpectedly exacerbated liver tumorigenesis when liver acetyl-CoA carboxylase (ACC) 1 and 2 enzymes were deleted in mice treated with diethylnitrosamine (DEN) and fed high fat diet. Herein, we used 3 new approaches including ACC1 vs. ACC2 isotype-selective inhibition, delaying ACC inhibition until after carcinogen treatment, and feeding mice normal chow diet to better understand the impact of ACC inhibition on liver tumorigenesis. Six genotypes of female C57BL/6J mice with floxed ACC1 and/or ACC2 alleles were injected with DEN at 2 weeks of age followed by liver-specific knockout of ACC genes at 9 weeks. Mice were fed a normal chow diet and evaluated at 52 weeks for liver tumours. Compared to the wildtype control group, no genotype decreased tumour multiplicity or burden; however, mice completely lacking liver ACC1 and ACC2 had > 5-fold increases in liver tumour multiplicity and burden. ACC inhibition exacerbated DEN-induced liver tumorigenesis only when both ACC isotypes were completely inhibited. The pro-tumour phenotype of ACC inhibition was strongly reproducible irrespective of chow or high fat feeding, and irrespective of ACC inhibition prior to or after DEN treatment. Retaining partial ACC activity at either isotype prevented tumour exacerbation in mice at risk for developing liver tumours.

RNF213 p.Arg4810Lys Variant Is Associated with Higher Stenosis Progression in Asymptomatic Intracranial Artery Stenosis.

Intracranial artery stenosis (ICAS) is a significant contributor to ischemic stroke, with the RNF213 p.Arg4810Lys variant identified as a related genetic factor. We explored the clinical outcomes of the RNF213 genotype in patients with asymptomatic ICAS. Between November 2011 and March 2019, 139 patients with asymptomatic ICAS were enrolled in this study. Genotyping for RNF213 p.Arg4810Lys was performed using Sanger sequencing. A comprehensive analysis was conducted to compare the RNF213 genotype with background characteristics and clinical outcomes such as ipsilateral ischemic cerebrovascular events and stenosis progression. RNF213 p.Arg4810Lys was found in 25% of cases, revealing distinct clinical features between carriers and non-carriers. The incidence of ipsilateral ischemic cerebrovascular events was 4.3% (6/139 cases), and stenosis progression was observed in 13% (18/139 cases) during a mean follow-up period of 58months. Stenosis progression rates were notably higher in the RNF213 variant group (25.7%; 9/35 cases) than in the RNF213 wild-type group (8.7%; 9/104 cases). Cumulative stenosis progression rate was significantly higher in the RNF213 variant group than in the RNF213 wild-type group (log-rank test, P = 0.0004). Multivariate Cox regression analysis indicated a significant association between the RNF213 p.Arg4810Lys variant and an increased risk of stenosis progression (P = 0.03, odds ratio 3.2; 95% confidence interval, 1.1-9.0). The RNF213 p.Arg4810Lys variant exhibits clinical disparities in asymptomatic ICAS and is notably linked to a heightened risk of stenosis progression. These results suggest a distinct difference in the vascular stenosis mechanism associated with this variant, warranting further investigation into its clinical implications and potential mechanistic insights.

CSIG-28. DISSECTING THE FUNCTIONAL IMPAIRMENT OF WILD-TYPE P53 IN HUMAN GLIOBLASTOMA

Abstract Glioblastoma (GBM) is the most common malignant brain tumor in adults and is characterized by heterogeneous nature, invasive potential, and poor treatment response. Work from The Cancer Genome Atlas (TCGA) identified the tumor suppressor gene TP53 as a GBM driver. In contrast to several cancers, only ~35% of GBM cases carry mutations in TP53. Work from our lab showed that TP53 mutations emerge as ‘late’ events during GBM growth. Therefore, we hypothesized that wild-type (wt) p53 function is impaired in GBM. We used the TCGA data of 591 GBM patients to compare the clinical and molecular characteristics of wt and mutant TP53 patients. Gene expression data were analyzed to compare the correlation of TP53 with the expression of key p53 regulators and identify differentially expressed regulators between our groups. Furthermore, we evaluated the expression of p53 and selected regulators in patient-derived cells (PDCs) and control lines with known TP53 status. Our results show that wt TP53 patients live less than mutant patients and both groups respond similarly to treatment. No differences in age, sex, race, TP53 levels, and MGMT methylation status were observed between the groups. Gene expression analyses revealed that MAPK8, a p53 activator, negatively correlates with TP53 in the wt group. Moreover, ~21% of p53 regulators are differentially expressed between wt and mutant patients. Among these, we selected SIRT3, a p53 repressor, for experimental validation. We verified the p53 genetic status of PDCs through western blot and confirmed Sirt3 expression in wt and mutant TP53 PDCs. By CRISPR-Cas9-based genomic editing, we are currently evaluating the impact of SIRT3 knockout in GBM-PDC and patient-derived xenografts. We expect that SIRT3 knockout will restore p53 function in the wt group. In conclusion, our results suggest that p53 function is impaired in wt patients and provide insights into mechanisms affecting its activity.

The Role of FLT3-ITD Mutation, PI3K/AKT Pathway, and Leukemia Stem Cells in D3A7 Induction therapy – the Outcomes of Adult Indonesian Patients with Acute Myeloid Leukemia

Objective. This cohort study aimed to examine the impact of the FLT3-ITD mutation on the downstream signaling pathway of PI3K/AKT pathway, the percentage of leukemia stem cells, and the survival of patients receiving D3A7 induction therapy. Method. Bone marrow mononuclear cells were collected from 20 adult AML patients who had completed D3A7 induction therapy at Cipto Mangunkusumo National General Hospital and Dharmais Cancer Hospital. FLT3-ITD gene mutation was examined by the PCR-sequencing method. Expression of phosphorylated PI3K and AKT was detected using the sandwich ELISA method. Flow cytometry was used for detecting the number of apoptosis and proliferation cells, and biomarkers of leukemia stem cells. Result. The expression levels of PI3K and AKT proteins were higher in FLT3-ITD, both in the mutant group compared to the non-mutation group, and in the patient group with treatment failure outcomes compared to the patient group with treatment response. The percentage of the leukemia stem cell population did not differ significantly between the FLT3-ITD mutation group and the wild type group, and between the treatment failure outcome group and the response outcome group. Conclusion. This study presents the important role of FLT3-ITD mutation via its downstream signaling (PI3K/AKT) in the outcome of D3A7 induction therapy. The FLT3-ITD mutation plays an important role in the 12-month survival of AML patients after D3A7 therapy. However, the outcome of D3A7 therapy and FLT3-ITD mutation were not associated with leukemia stem cells.

Influence of TMPRSS6 genotype on iron status parameters in stable COPD patients

Background: The SNP rs855791 has been linked to increased hepcidin levels, variations in serum iron, transferrin saturation and red blood cell indices. Our goal was to determine the prevalence of this polymorphism among COPD patients and to assess its impact on iron status parameters including hepcidin in patients with stable COPD. Methods: We analysed iron status parameters and genetic data form 94 COPD patient: 29 patients with wild-type genotype (WT group) and 65 patients with either homozygous or heterozygous genotype (HH group). Additionally, the prevalence of SNP rs855791 was assessed in 192 volunteers. Results: The frequency distribution of SNP rs855791 was comparable between the COPD patients and control subjects (p=0.791). Iron status parameters were within their respective reference values and did not show neither statistically nor clinically significant difference between the WT and HH group of COPD patients. However, after excluding patients with (sub)clinical vitamin B12 deficiency and/or hypoxemia, WT group of patients exhibited significantly lower erythropoietin levels (p=0.015). The area under the curve for EPO was 0.688 (95% CI: 0.545-0.830, p=0.015), with an optimal cut-off of 9.74, sensitivity of 61.2% (95% CI: 58.1-64.3) and specificity of 65.0% (95% CI: 61.8-68.3). Conclusion: In patients with stable COPD, iron status parameters do not differ between WT and HH group of patients. After excluding those with (sub)clinical vitamin B12 deficiency and/or hypoxia, only statistical and not clinical difference in EPO levels was observed suggesting that EPO may regulate hepcidin levels and thus influence the development of iron deficiency and/or anaemia.

A Novel Cell- and Virus-Free SARS-CoV-2 Neutralizing Antibody ELISA Based on Site-Specific Labeling Technology.

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) led to the global spread of coronavirus disease 2019 (COVID-19), creating an urgent need for updated methods to evaluate immune responses to vaccines and therapeutic strategies. In this study, we introduce a novel cell-free, virus-free SARS-CoV-2 neutralizing antibody ELISA (NAb-ELISA), which is based on competitive inhibition of the receptor binding domain (RBD) of spike protein binding to the angiotensin-converting enzyme 2 (ACE2) receptor. In this method, site-specific biotinylated hACE2-Fc-Avi recombinant protein is immobilized onto a 96-well plate for capture, and the RBD-Fc-vHRP recombinant proteins serve as detection probes. Evaluation of sera from wild type (WT) or Delta RBD-immunized mice using the NAb-ELISA and pseudovirus neutralization tests (pVNTs) demonstrated strong correlations between assays (R2 = 0.91 and 0.90 for the WT and Delta groups, respectively). Additionally, the NAb-ELISA successfully detected cross-neutralizing activity in sera, though with slightly lower correlation to pVNT (R2 = 0.70-0.83). By employing NAb-ELISA instead of an indirect ELISA for hybridoma screening, five monoclonal antibodies (mAbs) with neutralizing activities against WT, Delta, and BA.2 pseudoviruses were obtained. This assay offers a straightforward, rapid, and safe approach to characterizing vaccine-induced antibody responses and mAb neutralization activity. Notably, the NAb-ELISA platform can be quickly adapted to assess neutralizing antibody responses against emerging mutant strains, addressing the rapid mutation of the virus.

The GDF15 3′ UTR Polymorphism rs1054564 Is Associated with Diabetes and Subclinical Atherosclerosis

Growth differentiation factor 15 (GDF15) is a stress-response cytokine related to a wide variety of metabolic diseases. However, the impact of GDF15-specific genetic variants on the abovementioned conditions is poorly known. The aim of this study was to assess the impact of selected GDF15 single-nucleotide polymorphisms (SNPs) on metabolic disturbances and subclinical atherosclerosis. A cross-sectional study involving 153 participants of a metabolic patient-based cohort was performed. Three selected SNPs (rs888663, rs1054564 and rs1059369) in a locus on chromosome 19 including the GDF15 gene were genotyped by Polymerase Chain Reaction (PCR), and its relationship with the serum GDF15 levels, health status and clinical variables were analyzed. Of the three SNPs analyzed, only rs1054564 showed different distributions between the healthy volunteers and patients suffering lipid alterations and associated disorders. Accordingly, just the rs1054564 variant carriers showed a significant increase in GDF15 serum levels compared to the wild-type carriers. The group of variant carriers showed a higher frequency of individuals with diabetes, compared to the wild-type carrier group, without showing differences in other metabolic conditions. Additionally, the frequency of individuals with atherosclerotic carotid plaque was higher in the rs1054564 variant carriers than in the wild-type carriers. Logistic regression models identified that the presence of the rs1054564 variant carriers increase the likelihood for both diabetes and carotid plaque independently of confounding factors. Overall, the findings of this study identify the rs1054564 variant as a potential indicator for the likelihood of diabetes and subclinical atherosclerosis.

Co-mutation of TP53 and TTN is Correlated with the Efficacy of Immunotherapy in Lung Squamous Cell Carcinoma.

Immunotherapy has been a promising treatment in advanced lung cancer. However, only a few patients could benefit from it. Herein, we aimed to explore mutationrelated predictive biomarkers in lung squamous cell carcinoma (LUSC), which could help develop clinical immunotherapy strategies and screen beneficial populations. Co-occurrence and mutually exclusive analysis was conducted on the TCGA-LUSC cohort. Correlations between the gene mutation status and tumor mutation burden (TMB) levels, and neo-antigen levels were analyzed by Wilcoxon test. Kaplan-Meier method was employed to analyze the progression-free survival (PFS) of lung cancer patients with immunotherapy. Gene set enrichment analysis (GSEA) was used to investigate the functional changes affected by TP53mut/TTNmut. The immune cell infiltration landscape in co-mutation subgroups was analyzed using CIBERSORT. 1) TP53, TTN, CSMD3, MUC16, RYR2, LRP1B, USH2A, SYNE1, ZFHX4, FAM135B, KMT2D, and NAV3 were frequently mutated in LUSC patients. 2) TMB levels in highly mutated groups were higher than that in wild type groups. 3) There were higher neoantigen levels in mutation group compared to the wild-type group, and LUSC patients in mutation group had longer PFS. 4) TP53mut/TTNmut co-mutation group exhibited higher TMB levels and better response to immunotherapy. 5) A host of immune-related signaling pathways was inhibited in TP53mut/TTNmut subgroup. 6) There were more T follicular helper cells and NK cells were in TP53mut/TTNmut subgroup than in the WT subgroup. The LUSC patients with TP53 and TTN co-mutation had higher TMB levels and better response to immunotherapy. The TP53 and TTN co-mutation is a promising novel biomarker to assist LUSC immunotherapy evaluation.

Fibroblast-specific deletion of ERBB4 impairs cardiac regeneration in neonatal mice

Abstract Background Scarless regeneration of the neonatal mammalian heart is a remarkable but poorly understood process. Previous studies have shown that paracrine actions of neuregulin-1 (NRG1) are indispensable to stimulate cardiomyocyte proliferation in the injured neonatal heart, and are mediated by activation of the ERBB4 receptor. It remains unclear, however, whether NRG1 also contributes to other steps of neonatal cardiac regeneration, e.g. to the control of collagen synthesis by fibroblasts, hence contributing to scarless healing. Purpose To study temporal evolution of the infarct size during 21 days after myocardial infarction (MI) in neonatal fibroblast-specific Erbb4 knock-out (KO) and wild type (WT) mice. We hypothesized that scarless healing would be completed within 21 days in WT mice, and incomplete in KO mice. Methods Fibroblast-specific hemizygous Erbb4 KO (FB-Erbb4-KO) mice were generated (Erbb4F/+ Col1a2-Cre+, C57BL/6 background), because fibroblast-specific nullizygous Erbb4 KO were not viable. Validation of the KO was performed both on RNA (qPCR) and protein (western blot) level. MI was induced in one-day old FB-Erbb4-KO and WT littermates of both sexes by permanent ligation of the left anterior descending (LAD) coronary artery under hypothermic anaesthesia. Pups from both groups were euthanized at 4 (WT, n=9; KO, n=11), 7 (WT, n=12; KO, n=4), 10 (WT, n=11; KO, n=7) and 21 (WT, n=16; KO, n=8) days post-MI. Following dissection, hearts were formalin-fixed and paraffin embedded for histopathological evaluation. Transverse sections were cut at 4 distinct locations from the ligation site to the apex and stained with Masson’s Trichrome for infarct scar measurement. Genotyping was performed post-mortem and unblinded after data analysis. Results Both the transgenic mice model and the LAD ligation technique were successfully validated. No significant differences in the initial infarct scar size were observed between WT and FB-Erbb4-KO mice 4 days post-MI (p=0.6556). 7-days post-MI the infarct scar size was 6-fold smaller compared to 4 days post-MI in both FB-Erbb4-KO and WT mice, with a trend towards a larger infarct scar size in the FB-Erbb4-KO group compared to WT (p=0.0989). At day 10 post-MI, infarct scar size in the FB-Erbb4-KO group was significantly larger (p=0.0499) compared to WT. At 21 days post-MI, the infarct size had almost completely disappeared in the WT group, but remained clearly present in the FB-Erbb4-KO group (Fig. 1, p=0.0099). Infarct scar sizes at all timepoints are graphically shown in Fig. 2. Conclusion Fibroblast-specific deletion of the ERBB4 receptor causes incomplete resolution of the infarct scar in murine neonates 21 days after MI. While the initial infarct scar size 4 days after injury is the same, impaired scar resolution becomes progressively more evident towards day 21 post-MI. These findings indicate that scarless healing of the neonatal mammalian heart requires NRG1/ERBB4 signalling in fibroblasts.Fig. 1Fig. 2

Mitochondrial Oxidative Stress and Cardiac Dysfunction in TERT Knockout Mice

Abstract Background Heart failure (HF) is a major cause of hospitalization in the elderly, with its incidence increasing due to aging and associated risk factors like hypertension, diabetes, and myocardial fibrosis. Aging-related myocardial fibrosis, characterized by alterations in the extracellular matrix and myocardial structure, impairs cardiac function. Mitochondrial oxidative stress plays a pivotal role in cardiac electrical and structural remodeling, necessitating a deeper understanding of its involvement in aging-related heart failure. Purpose The purpose of this study is to investigate the mechanisms of aging-related ventricular electrical and structural remodeling by constructing an aging mouse model. This research aims to provide potential therapeutic targets for heart failure associated with aging. Methods We developed a third-generation homozygous telomerase reverse transcriptase (TERT) knockout mouse model. Comparing third-generation homozygous TERT knockout mice (F3 group) with age-matched wild-type males (WT group). The study encompassed blood pressure measurement, electrocardiographic analysis, echocardiography, ELISA for cardiac biomarkers, ventricular tissue electrophysiology, fibrosis assessment through staining, transcriptomic profiling via RNA-seq, and electron microscopy of ventricular mitochondria. Results Compared to the WT group, the F3 group demonstrated increased P53 and P16 protein expression. Decreased LVEF and FS, along with increased interventricular septum thickness, left ventricular diameter, and left ventricular volume. Elevated serum NT-pro-BNP and troponin I (cTnI) levels, with prolonged QRS duration. Decreased left and right ventricular conduction velocity, accompanied by increased conduction dispersion. Notable elevation in COLI, TGFβ, and α-SMA gene transcription and protein expression in ventricular tissue. Significant differences in mitochondrial oxidative stress signal pathways via RNA-seq analysis. Elevated serum MDA levels and decreased SOD levels, with up-regulated Mn-SOD gene transcription and protein expression, and down-regulated MFN2 and Drp1 gene transcription and protein expression in ventricular tissue. Electron microscopy revealed mitochondrial abnormalities such as loose arrangement, decreased number, swelling, vacuolation, and myofilament disintegration or breakage in the F3 group. Conclusion Third-generation TERT-/- senescent mice exhibit notable cardiac impairments, including electrical remodeling, structural changes, and mitochondrial dysfunction. These findings suggest a potential link between mitochondrial oxidative stress and aging-related heart failure, indicating novel therapeutic opportunities targeting mitochondrial dysfunction for managing such conditions.

Protective role of Metrnl on macrophage recruitment during the acute inflammatory phase in a mouse model of myocardial infarction

Abstract Introduction Meteorin-like protein (Metrnl) is a cytokine involved in the attenuation of inflammation. Previously, a cardioprotective role of Metrnl against cardiac hypertrophy and ischemia/reperfusion has been described. After myocardial infarction (MI), macrophages recruited from the spleen, and their capacity to shift from inflammatory (M1) to reparative (M2) phases determines the fate of cardiac repair. Purpose The aim of this study was to analyse the function of Metrnl in a mouse model of permanent MI during the acute inflammatory phase. Methods Wild-type (WT), Metrnl Knock-out (Metrnl-/-) and Metrnl-reconstituted Metrnl-/- mice (AAV9-Metrnl, with myocardial-specific tropism) were subjected to MI by coronary artery ligation. After 4 days, cardiac function was assessed using echocardiography at baseline and 4 days post-MI. Monocyte populations were analysed in spleen and blood by flow cytometry, and macrophages infiltrating the infarcted myocardium by gene expression analyses. Results Echocardiographic analysis demonstrated that Metrnl deficiency led to cardiac dysfunction (FAC p=0.02) accompanied by myocardial dilation 4 days post-MI (EDV p=0.02; ESV p=0.01). On the contrary, the overexpression of Metrnl in the myocardium of AVV9-Metrnl mice restored cardiac function compared to Metrnl-/- group (FAC p=0.01, EDV p=0.04, ESV p=0.09). Furthermore, we observed a reduction in splenic monocytes (CD11b+F4/80+) in Metrnl-/- mice compared to the WT group at 4 days post-MI (p=0.06). In particular, a significant decrease in pro-inflammatory Ly6CHigh and CD86+ monocytes was noted in the spleens of Metrnl-/- mice compared to the WT group (p=0.03; p=0.04 respectively), suggesting their mobilization out of the spleen, but not in the AVV9-Metrnl group. Although the total number of Ly6CHigh and Ly6CLow monocytes in the bloodstream was similar in all groups, there was a trend to different expression in the CCR2 and CCR5 chemokine receptors (p=0.07; p=0.06 respectively). At the same time, M1 macrophage recruitment chemokines (CCL2) and inflammatory markers (TNFα) were significantly induced in the ischemic area of the infarcted myocardium compared to the remote zone in the WT and Metrnl-/- groups (CCL2 p=0.03; p=0.01 respectively; TNFα p=0.008;p=0.04 respectively). In contrast, TNFα and CCL2 genes were not induced in the ischemic area of AVV9-Metrnl mice. Regarding M2 macrophages, the Arg1 marker was significantly reduced in the ischemic zone of Metrnl-/- mice compared to the WT group (p= 0.01), while in the AVV9-Metrnl group was recovered (p= 0.04). Conclusions Our results demonstrate that the absence of Metrnl promotes the recruitment of inflammatory macrophages to the ischemic myocardium and is associated to cardiac dysfunction.

Ninjurin1 deficiency differentially mitigates colorectal cancer induced by azoxymethane and dextran sulfate sodium in male and female mice.

This study investigated the role of Ninjurin1 (Ninj1), encoding a small transmembrane protein, in colitis-associated colon tumorigenesis in relation to sex hormones. Male and female wild-type (WT) and Ninj1 knockout (KO) mice were treated with azoxymethane (AOM) and dextran sulfate sodium (DSS), with or without testosterone propionate (TP). At week 2 (acute colitis stage), Ninj1 KO exhibited an alleviation in the colitis symptoms in both male and female mice. The M2 macrophage population increased and CD8+ T cell population decreased only in the female Ninj1 KO than in the female WT AOM/DSS group. In the female AOM/DSS group, TP treatment exacerbated colon shortening in the Ninj1 KO than in the WT. At week 13 (tumorigenesis stage), male Ninj1 KO mice had fewer tumors, but females showed similar tumors. In the WT AOM/DSS group, females had more M2 macrophages and fewer M1 macrophages than males, but this difference was absent in Ninj1 KO mice. In the Ninj1 KO versus WT group, the expression of pro-inflammatory mediators and Ho-1 and CD8+ T cell populations decreased in both female and male Ninj1 KO mice. In the WT group, M2 macrophage populations were increased by AOM/DSS treatment and decreased by TP treatment. However, neither treatment changed the cell populations in the Ninj1 KO group. These results suggest that Ninj1 is involved in colorectal cancer development in a testosterone-dependent manner, which was different in male and female. This highlights the importance of considering sex disparities in understanding Ninj1's role in cancer pathogenesis.

Aerobic exercise prevents and improves cognitive dysfunction caused by morphine withdrawal via regulating endogenous opioid peptides in the brain.

Morphine withdrawal leads to serious cognitive deficits in which dynorphins are directly involved. Recently, exercise has been shown to prevent and improve cognition dysfunction in a variety of ways. Meanwhile, exercise can regulate the endogenous opioid peptides including dynorphins. However, it remains unclear whether exercise influences cognitive dysfunction caused by morphine withdrawal via dynorphins. In the current study, we investigate the physiological mechanism of exercise prevention and improvement aganist cognition dysfunction caused by morphine withdrawal. Male, adult C57BL/6 mice were randomly divided into 5 groups : Saline control (WT), exercise (EXE), morphine withdrawl (MW), exercise + morphine withdrawl (EMW), morphine withdrawl + exercise (MWE). We established aerobic exercise prevention/improvement models, and conducted behavioral tests including Open field test (OFT), Temporal order memory test (TOM) and Y-maze. Through Western Blotting and immunofluorescence staining, we detected endogenous opioid peptides in hippocampus and mPFC. Compared with MW group, EMW group and MWE group showed the same performance as WT group in TOM and Y-maze, with correct object recognition and memory ability. In Western Blotting and immunofluorescence staining experiments, it indicated that EMW group reduced the expression of PDYN and its fluorescence intensity in hippocampus; MWE group reduced the expression of OPRK1 and its fluorescence intensity in mPFC. Our data suggest that aerobic exercise can both prevent and improve cognitive dysfunction caused by acute morphine withdrawal via respectively down-regulating PDYN in the hippocampus and down-regulating OPRK1 in the mPFC. They may become new targets for drugs development in the future.

Analysis of low-density lipoprotein receptor gene mutations in a family with familial hypercholesterolemia.

Familial hypercholesterolemia (FH) is a common monogenic autosomal dominant disorder, primarily mainly caused by pathogenic mutations in the low-density lipoprotein receptor (LDLR) gene. Through phenotypic-genetic linkage analysis, two LDLR pathogenic mutations were identified in FH families: c.G1027A (p.Gly343Ser) and c.G1879A (p.Ala627Thr). Whole exome sequencing was conducted on the proband with familial hypercholesterolemia to identify the target gene and screen for potential pathogenic mutations. The suspicious responsible mutation sites in 14 family members were analyzed using Sanger sequencing to assess genotype-phenotype correlations. Mutant and wild type plasmids were constructed and transfected into HEK293T cells to evaluate LDLR mRNA and protein expression. In parallel, bioinformatics tools were employed to predict structural and functional changes in the mutant LDLR. Immunofluorescence analysis revealed no significant difference in the intracellular localization of the p.Gly343Ser mutation, whereas protein expression of the p.Ala627Thr mutation was decreased and predominantly localized in the cytoplasm. Western blotting has showed that protein expression levels of the mutant variants were markedly declined in both cell lysates and supernatants. Enzyme linked immunosorbent assay has demonstrated that LDLR protein levels in the supernatant of cell culture medium was not significant different from those of the wild-type group. However, LDLR protein levels in the cell lysate of both the Gly343Ser and Ala627Thr variants groups were significantly lower than those in the wild-type group. Bioinformatic predictions further suggested that these mutations may affect post-translational modifications of the protein, providing additional insight into the mechanisms underlying the observed reduction in protein expression. In this study, we identified two heterozygous pathogenic variants in the LDLR gene, c.G1027A (p.Gly343Ser) and c.G1879A (p.Ala627Thr), in a family with familial hypercholesterolemia. We also conducted preliminary investigations into the mechanisms by which these mutations contribute to disease pathology.

Impaired brain glucose metabolism in glucagon-like peptide-1 receptor knockout mice

BackgroundQuantitative mapping of the brain’s metabolism is a critical tool in studying and diagnosing many conditions, from obesity to neurodegenerative diseases. In particular, noninvasive approaches are urgently required. Recently, there have been promising drug development approaches for the treatment of disorders related to glucose metabolism in the brain and, therefore, against obesity-associated diseases. One of the most important drug targets to emerge has been the Glucagon-like peptide-1 (GLP-1) and its receptor (GLP-1R). GLP and GLP-1R play an important role in regulating blood sugar and maintaining energy homeostasis. However, the macroscopic effects on brain metabolism and function due to the presence of GLP-1R are unclear.MethodsTo explore the physiological role of GLP-1R in mouse brain glucose metabolism, and its relationship to brain function, we used three methods. We used deuterium magnetic resonance spectroscopy (DMRS) to provide quantitative information about metabolic flux, fluorodeoxyglucose positron emission tomography (FDG-PET) to measure brain glucose metabolism, and resting state-functional MRI (rs-fMRI) to measure brain functional connectivity. We used these methods in both mice with complete GLP-1R knockout (GLP-1R KO) and wild-type C57BL/6N (WT) mice.ResultsThe metabolic rate of GLP-1R KO mice was significantly slower than that of WT mice (p = 0.0345, WT mice 0.02335 ± 0.057 mM/min, GLP-1R KO mice 0.01998 ± 0.07 mM/min). Quantification of the mean [18F]FDG signal in the whole brain also showed significantly reduced glucose uptake in GLP-1R KO mice versus control mice (p = 0.0314). Observing rs-fMRI, the functional brain connectivity in GLP-1R KO mice was significantly lower than that in the WT group (p = 0.0032 for gFCD, p = 0.0002 for whole-brain correlation, p < 0.0001 for ALFF).ConclusionsGLP-1R KO mice exhibit impaired brain glucose metabolism to high doses of exogenous glucose, and they also have reduced functional connectivity. This suggests that the GLP-1R KO mouse model may serve as a model for correlated metabolic and functional connectivity loss.

Characterization of somatic mutations in sporadic uveal melanoma and uveal melanoma in patients with germline BAP1 pathogenic variants.

Genetic analyses were conducted on tumor samples from 88 patients with uveal melanoma (UM), 6 of whom carry pathogenic germline variants in BAP1. We assessed the frequency, pattern, and prognostic significance of somatic aberrations, and investigated differences between germline BAP1 variant carriers compared to sporadic cases. The frequency of the main oncogenic driver mutations was not significantly different between these groups. Patients with germline BAP1 variants did not have significantly different overall survival compared to the wildtype or somatic BAP1 mutation groups. Patients with a somatic BAP1 mutation (n = 24) had a significantly worse prognosis compared to wildtype (n = 58). All patients with stage III tumors and a somatic BAP1 mutation (n = 7) developed metastasis, however four of 28 stage I-II tumors without metastasis had somatic BAP1 mutations, with observation time >5 years. The tumor from one germline BAP1 carrier (stage IIIC) with a somatic EIF1AX splice variant, has not developed metastasis within a 22-year observation time.

Dynamic contrast enhanced MRI demonstrate altered placental perfusion in the STOX1A preeclampsia mouse model

IntroductionPreeclampsia, a hypertensive disorder of pregnancy triggered by placental dysfunction, is reproduced in the murine STOX1A model, with hypertension, proteinuria, and abnormalities in umbilical and uterine Dopplers. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is an innovative technique that provides insights into tissue perfusion. The present study aims at analyzing placental perfusion using DCE-MRI to further characterize placental defects in the STOX1A model. MethodsTwo study groups were formed: the "TgSTOX13 pregnancy group" from mating TgSTOX13 genotype males with wild-type females, and the "wild-type pregnancy group" from mating wild-type males with wild-type females. Blood pressure, urinary albumin to creatinine ratio, and fetal weights were measured and compared between the groups, while perfusion parameters were analyzed using both conventional compartmental (1C) and free-time point-Hermite (FTPH) models in the DCE analysis. ResultsSeventeen pregnant mice in the "TgSTOX13 pregnancy group" and thirteen in the "wild-type pregnant group" were included in the analysis. During late gestation, the TgSTOX13 pregnancy group exhibited higher blood pressure, elevated albumin/creatinine ratio, and decreased fetal weights compared to the wild-type pregnancy group. In the DCE analysis utilizing the 1C model, blood flow (Fb) was significantly reduced by approximately 31.8 % in the TgSTOX13 pregnancy group compared to the wild-type pregnancy group (p < 0.01), a finding corroborated by the FTPH model with a reduction estimated at 31.5 % (p < 0.01). DiscussionOur investigation successfully utilized DCE MRI to assess placental perfusion in a mouse model of preeclampsia, revealing a significant reduction of approximately 30 % in the preeclamptic mice, mirroring human pathophysiology.