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The transcription factor NF-E2 p45-related factor 2 (Nrf2) is an established master regulator of the anti-oxidative and detoxifying cellular response. Thus, a role in inflammatory diseases associated with the generation of large amounts of reactive oxygen species (ROS) seems obvious. In line with this, data obtained in cell culture experiments and preclinical settings have shown that Nrf2 is important in regulating target genes that are necessary to ensure cellular redox balance. Additionally, Nrf2 is involved in the induction of phase II drug metabolizing enzymes, which are important both in degrading and converting drugs into active forms, and into putative carcinogens. Therefore, Nrf2 has also been implicated in tumorigenesis. This must be kept in mind when new therapy approaches are planned for the treatment of sepsis. Therefore, this review highlights the function of Nrf2 in sepsis with a special focus on the translation of rodent-based results into sepsis patients in the intensive care unit (ICU).
Depletion of yeast/fly Ataxin-2 rescues TDP-43 overexpression toxicity. In mouse models of Amyotrophic Lateral Sclerosis via TDP-43 overexpression, depletion of its ortholog ATXN2 mitigated motor neuron degeneration and extended lifespan from 25 days to >300 days. There is another ortholog in mammals, named ATXN2L (Ataxin-2-like), which is almost uncharacterized but also functions in RNA surveillance at stress granules. We generated mice with Crispr/Cas9-mediated deletion of Atxn2l exons 5-8, studying homozygotes prenatally and heterozygotes during aging. Our novel findings indicate that ATXN2L absence triggers mid-gestational embryonic lethality, affecting female animals more strongly. Weight and development stages of homozygous mutants were reduced. Placenta phenotypes were not apparent, but brain histology showed lamination defects and apoptosis. Aged heterozygotes showed no locomotor deficits or weight loss over 12 months. Null mutants in vivo displayed compensatory efforts to maximize Atxn2l expression, which were prevented upon nutrient abundance in vitro. Mouse embryonal fibroblast cells revealed more multinucleated giant cells upon ATXN2L deficiency. In addition, in human neural cells, transcript levels of ATXN2L were induced upon starvation and glucose and amino acids exposure, but this induction was partially prevented by serum or low cholesterol administration. Neither ATXN2L depletion triggered dysregulation of ATXN2, nor a converse effect was observed. Overall, this essential role of ATXN2L for embryogenesis raises questions about its role in neurodegenerative diseases and neuroprotective therapies.
Objectives: The aim of this study was to investigate the relationship between anamnestic, axiographic and occlusal parameters and postural control in healthy women aged between 41 and 50 years. Materials and methods: A total of 100 female participants aged between 41 and 50 (45.12 ± 2.96) years participated in the study. In addition to completing a general anamnesis questionnaire, lower jaw movements were measured axiographically, dental occlusion parameters were determined using a model analysis and postural parameters were recorded using a pressure measurement platform. The significance level was 5%. Results: An increasing weight and a rising BMI lead to a weight shifted from the rearfoot (p ≤ 0.01/0.04) to the forefoot (p ≤ 0.01/0.02). A limited laterotrusion on the right resulted in a lower forefoot load and an increased rearfoot load (p ≤ 0.01). Laterotrusion to the left (extended above the standard) showed a lower frontal sway (p ≤ 0.02) and a reduced elliptical area, height and width (p ≤ 0.01, 0.02, 0.03). Thus, the extent of deviation correlated with reduced right forefoot loading (p ≤ 0.03) and the extent of deflection correlated with increased left foot loading (p ≤ 0.01). The higher the extent of angle class II malocclusion, the larger the ellipse area (p ≤ 0.04) and the ellipse height (p ≤ 0.02) resulted. Conclusions: There is a connection between weight, BMI and laterotrusion, as well as between angle class II malocclusion and postural control in women aged between 41 and 50 years. Interdisciplinary functional examinations of mandibular movements treating possible limitations can be conducive for an improvement of postural control. Clinical relevance: Angle class II malocclusion has a negative influence on postural control.
Zinc finger proteins (ZNF) are a large group of transcription factors with diverse functions. We recently discovered that endothelial cells harbour a specific mechanism to limit the action of ZNF354C, whose function in endothelial cells is unknown. Given that ZNF354C has so far only been studied in bone and tumour, its function was determined in endothelial cells. ZNF354C is expressed in vascular cells and localises to the nucleus and cytoplasm. Overexpression of ZNF354C in human endothelial cells results in a marked inhibition of endothelial sprouting. RNA-sequencing of human microvascular endothelial cells with and without overexpression of ZNF354C revealed that the protein is a potent transcriptional repressor. ZNF354C contains an active KRAB domain which mediates this suppression as shown by mutagenesis analysis. ZNF354C interacts with dsDNA, TRIM28 and histones, as observed by proximity ligation and immunoprecipitation. Moreover, chromatin immunoprecipitation revealed that the ZNF binds to specific endothelial-relevant target-gene promoters. ZNF354C suppresses these genes as shown by CRISPR/Cas knockout and RNAi. Inhibition of endothelial sprouting by ZNF354C is dependent on the amino acids DV and MLE of the KRAB domain. These results demonstrate that ZNF354C is a repressive transcription factor which acts through a KRAB domain to inhibit endothelial angiogenic sprouting.
Background: Recently, RBFOX1, a gene encoding an RNA binding protein, has consistently been associated with aggressive and antisocial behavior. Several loci in the gene have been nominally associated with aggression in genome-wide association studies, the risk alleles being more frequent in the general population. We have hence examined the association of four RBFOX1 single nucleotide polymorphisms, previously found related to aggressive traits, with aggressiveness, personality, and alcohol use disorder in birth cohort representative samples.
Methods: We used both birth cohorts of the Estonian Children Personality Behavior and Health Study (ECPBHS; original n = 1,238). Aggressiveness was assessed using the Buss–Perry Aggression Questionnaire and the Lifetime History of Aggressiveness structured interview at age 25 (younger cohort) or 33 (older cohort). Big Five personality at age 25 was measured with self-reports and the lifetime occurrence of alcohol use disorder assessed with the MINI interview. RBFOX1 polymorphisms rs809682, rs8062784, rs12921846, and rs6500744 were genotyped in all participants. Given the restricted size of the sample, correction for multiple comparisons was not applied.
Results: Aggressiveness was not significantly associated with the RBFOX1 genotype. RBFOX1 rs8062784 was associated with neuroticism and rs809682 with extraversion. Two out of four analyzed RBFOX1 variants, rs8062784 and rs12921846, were associated with the occurrence of alcohol use disorder.
Conclusions: In the birth cohort representative sample of the ECPBHS, no association of RBFOX1 with aggressiveness was found, but RBFOX1 variants affected basic personality traits and the prevalence of alcohol use disorder. Future studies on RBFOX1 should consider the moderating role of personality and alcohol use patterns in aggressiveness.
The influence of delayed auditory feedback on action evaluation and execution of real-life action-induced sounds apart from language and music is still poorly understood. Here, we examined how a temporal delay impacted the behavioral evaluation and neural representation of hurdling and tap-dancing actions in a functional magnetic resonance imaging (fMRI) experiment, postulating that effects of delay diverge between the two, as we create action-induced sounds intentionally in tap dancing, but incidentally in hurdling. Based on previous findings, we expected that conditions differ regarding the engagement of the supplementary motor area (SMA), posterior superior temporal gyrus (pSTG), and primary auditory cortex (A1). Participants were videotaped during a 9-week training of hurdling and tap dancing; in the fMRI scanner, they were presented with point-light videos of their own training videos, including the original or the slightly delayed sound, and had to evaluate how well they performed on each single trial. For the undelayed conditions, we replicated A1 attenuation and enhanced pSTG and SMA engagement for tap dancing (intentionally generated sounds) vs. hurdling (incidentally generated sounds). Delayed auditory feedback did not negatively influence behavioral rating scores in general. Blood-oxygen-level-dependent (BOLD) response transiently increased and then adapted to repeated presentation of point-light videos with delayed sound in pSTG. This region also showed a significantly stronger correlation with the SMA under delayed feedback. Notably, SMA activation increased more for delayed feedback in the tap-dancing condition, covarying with higher rating scores. Findings suggest that action evaluation is more strongly based on top–down predictions from SMA when sounds of intentional action are distorted.
The float serve is an effective weapon to impede the attack of the opposing team. Because of its great importance in indoor and beach volleyball, we measured and quantified the float effect. We recorded 24 float serves of 12 top athletes in beach volleyball and indoor volleyball, respectively, and analyzed them using video analysis. We determined the 3D trajectories of the ball flight and developed two measures to describe the size of the float effect, the mean residuals and the anticipation error. Both were derived from regression models. These measures suggest that the float effect is greater in the vertical plane than in the horizontal plane, both for indoor and beach volleyball. Analyses of ball release velocities suggest that a certain ball release velocity is a necessary, but not sufficient, condition for ball floating. A validation of the float measurements with subjective expert ratings showed a correlation with the horizontal deviations. This study provides a new approach to analyze floating in on-court volleyball serves and broadens the knowledge for float effects in sports.
Simple Summary: Therapeutic antibodies are an integral part of treatment regimens for metastasized colorectal cancer. In KRAS wildtype tumors both bevacizumab and cetuximab are active. While bevacizumab has previously been shown to induce tumor hypoxia, we here report that EGFR inhibition by cetuximab protects colon cancer cells from hypoxia-induced cell death. This effect appears to be responsible for the inferior efficacy of a treatment sequence of bevacizumab followed by cetuximab versus an inverse sequence that we observed in a colorectal cancer mouse model. It also offers a mechanistic explanation for effects observed in clinical trials such as underadditive or even detrimental effects when combining bevacizumab and cetuximab (CAIRO2 trial) and the superior efficacy of first line cetuximab (FIRE-3 trial) under chemotherapy backbones in colorectal cancer.
Abstract: Monoclonal antibodies like cetuximab, targeting the epidermal growth factor receptor (EGFR), and bevacizumab, targeting the vascular endothelial growth factor (VEGF), are an integral part of treatment regimens for metastasized colorectal cancer. However, inhibition of the EGFR has been shown to protect human glioma cells from cell death under hypoxic conditions. In colon carcinoma cells, the consequences of EGFR blockade in hypoxia (e.g., induced by bevacizumab) have not been evaluated yet. LIM1215 and SW948 colon carcinoma and LNT-229 glioblastoma cells were treated with cetuximab, PD153035, and erlotinib and analyzed for cell density and viability. The sequential administration of either cetuximab followed by bevacizumab (CET->BEV) or bevacizumab followed by cetuximab (BEV->CET) was investigated in a LIM1215 (KRAS wildtype) and SW948 (KRAS mutant) xenograft mouse model. In vitro, cetuximab protected from hypoxia. In the LIM1215 model, a survival benefit with cetuximab and bevacizumab monotherapy was observed, but only the sequence CET->BEV showed an additional benefit. This effect was confirmed in the SW948 model. Our observations support the hypothesis that bevacizumab modulates the tumor microenvironment (e.g., by inducing hypoxia) where cetuximab could trigger protective effects when administered later on. The sequence CET->BEV therefore seems to be superior as possible mutual adverse effects are bypassed.
Photochemical internalization (PCI) is a technology to induce a localized, intracellular enhancement of therapeutics that are processed through endosomal pathways, including gemcitabine in malignant cells. In addition to a direct phototoxic and tumoricidal effect, PCI specifically disrupts endosomal membranes and, thereby, the compartmentalization of certain cytotoxic compounds to enhance a drug’s intended intracellular target reach within the tissue treated.
Non-resectable extrahepatic cholangiocarcinoma (eCCA) is a common primary tumor and gemcitabine/cisplatin chemotherapy is widely considered standard of care for it. PCI is well suited as an endoscopic intervention, and clinical observations in three subjects participating in a phase I/IIa dose escalation safety trial are described. The trial included patients with perihilar, non-resectable CCA suitable for standard-of-care chemotherapy. Per protocol, a single endoscopic PCI procedure with gemcitabine was conducted at the initiation of standard gemcitabine/cisplatin therapy. Sixteen patients enrolled in the initial dose escalation phase of the trial, which later was extended to explore the safety of a second PCI procedure during chemotherapy.
While limited to a case series, the various clinical observations described here serve to illustrate the effects of localized, perihilar tumor targeting in appropriate patients by any safe methodology, including PCI. As previously indicated by clinical data using other localized treatment modalities, adding a directed, tumor-targeting treatment to systemic therapy to ameliorate the progressively expanding extrahepatic tumor burden can have important effects on the overall outcome of systemic treatment in many patients who have incurable eCCA.
Correct cellular function is ensured by a complex network of proteins and enzymes, regulating protein synthesis and degradation. This protein network, maintaining the so-called protein homeostasis, regulates those processes on multiple levels, producing new or degrading old proteins to cope with changing intra- and extracellular environments. Disturbance of this tightly regulated machinery can have severe effects on the cell and can lead to a variety of pathologies on organism level. Diseases including cancer, neurodegeneration and infections are associated with causative or consequent alterations in protein homeostasis. To understand the pathologies of these diseases, it is therefore critical to examine how perturbations of protein homeostasis affect cellular pathways and physiology. In the recent years, analysis of protein homeostasis networks has resulted in the development of novel therapeutic approaches. However, for many factors it remains unclear how the cell is affected, if they are disturbed. Protein synthesis and degradation represent immediate responses of the cell to changes and need to be studied in the right timeframe, making them difficult to access by common methodology. In this work we developed a new mass spectrometry (MS) based method to study protein synthesis and degradation on a system-wide scale. Multiplexed enhanced protein dynamic (mePROD) MS was developed, overcoming these limitations by special sample mixing and novel data analysis protocols. MePROD thereby enables the measurement of rapid and transient (e.g. minutes) changes in protein synthesis of thousands of proteins. During responses of the cell to stressors (e.g. protein misfolding, oxidation or infection), two major pathways regulate the protein synthesis: the Integrated Stress Response (ISR) and mammalian target of rapamycin (mTOR). Both pathways have been connected with various diseases in the past and are common therapy targets. Although both pathways target protein synthesis in stress responses, the set of targets regulated by these pathways was believed to differ. Through the new mePROD MS method we could measure a comprehensive comparison of both pathways for the first time, revealing comparable system-wide patterns of regulation between the two pathways. This changed the current view on the regulation elicited by these pathways and furthermore represents a useful resource for the whole field of research. We could further develop the mePROD method and decrease MS measurement time needed to obtain an in-depth dataset. Through implementation of logic based instrument methods, it was possible to enhance the number of measured proteins by approximately three-fold within the same measurement time.
The dynamics of protein synthesis and degradation are frequently modulated by pathogens infecting the cell to promote pathogen replication. At the same time, the cell counteracts the infection by modulating protein dynamics as well. To develop useful therapy approaches to fight infections, it therefore is necessary to understand the complex changes within the host cell during infections on a system-wide scale. In 2019, a novel coronavirus spread around the world, causing a world-wide health-crisis. To better understand this novel virus and its infection of the host cell we conducted a study applying the mePROD methodology and classical proteomics to characterize the dynamic changes during the infection course in vitro. We discovered that the infection remodeled a diverse set of host cell pathways (e.g. mRNA splicing, glycolysis, DNA synthesis and protein homeostasis) and thereby showed possible targets for antiviral therapy. By targeted inhibition of these pathways, we could observe that these pathways indeed are necessary for SARS-CoV-2 replication and their inhibition could reduce viral load in the cells. Another experimental approach focused on the dynamic changes of protein modification, namely phosphorylation, after infection with SARS-CoV-2. Here, we could show the very important participation of growth factor signaling pathways in viral proliferation. Both studies together revealed critical pathways that are needed for the viral proliferation and hence are promising candidates for further therapies. Subsequent targeting of these pathways by either already approved drugs (Ribavirin and Sorafenib) or drugs in clinical trials (2-deoxyglucose, Pladienolide-B, NMS-873, Pictilisib, Omipalisib, RO5126766 and Lonafarnib) could block viral replication in vitro and suggests important clinical approaches targeting SARS-COV-2 infection.