Role of microRNAs in leukocyte adhesion to human brain microvascular endothelium

MicroRNAs (miRs) are small non-coding regulatory RNAs that act through repression of protein translation and/or mRNA degradation at the post-transcriptional level. MiRs are critical players in the pathogenesis of many diseases, including 'neuroinflammatory disorders such as multiple sclerosis (MS), MS is characterized by leukocyte adhesion and infiltration subsequently leading to demyelination of nerve fibres. Leukocyte adhesion on brain endothelial cells (BEC) - the main cellular constituent of the blood-brain barrier (BBB) - is a complex multi-step process where activated BEC overexpress chemokines such as CCL2 and endothelial adhesion molecules (CAM) such as selectins, VCAM1 and ICAM1. Several therapies for MS target the common known mechanisms of leukocyte adhesion. Here, we studied whether specific endothelial miRs act as regulators of leukocyte adhesion to cultured human BEC in vitro, and hence whether they could be a potential therapeutic tool to prevent adhesion to endothelium, First, we characterised leukocyte adhesion using the monocytic (THP1) and T cell (Jurkat) lines under static conditions, interacting with the immortalized hCMEC/ 03 endothelial cell line as an in vitro model of the human BBB. Increased adhesion of both leukocytic cell lines to BEC was observed following treatment with TNFu and IFNy compared to unstimulated cells. Increased expression of both ICAM1 and VCAM1 by hCMEC/D3 cells was also observed following cytokine treatment. Cytokine-induced maximal VCAM1 and ICAM1 expression coincided with the observed maximal leukocyte adhesion to BEC at 24 h, Next, we established a novel flow-based leukocyte adhesion assay coupled with time lapse image acquisition, to mimic more closely the in vivo conditions. We successfully cultured and transfected hCMEC/D3 cells in six-channel chambers, connected to a flow system, to study leukocyte-endothelium interactions and firm adhesion, Second, we performed an initial screening of five cytokine-regulated BEC miRs, Of these five, miR-126 and miR-155 appeared to have the most significant effects on leukocyte adhesion to hCMEC/D3cells, We further investigated the roles of miR-126, miR-126* (the complement of miR-126), and miR-155 in leukocyte adhesion to BEC. MiR-126 and - 126* were down-regulated in cytokine stimulated BEC low levels of miR-126 increased adhesion of both cell lines, while low levels of miR-l26* increased THP-1, but reduced Jurkat adhesion. Elevated miR-l26 and miR-126* levels significantly prevented Jurkat and THP-1 cell adhesion to BEC both in unstimulated and cytokine-treated conditions. Furthermore, elevated miR-126 partially prevented cytokine-induced VCAM1 and CCL2 expression on BEC and an increased level of miR-126* partially prevented cytokine-induced E-selectin expression. In cytokine stimulated-BEC miR-155 was up-regulated, and decreasing the level of miR-155 reduced both T cell and monocyte adhesion to endothelium and VCAMl expression both in basal and in cytokine-stimulated conditions, The opposite effect on leukocyte adhesion was observed when miR-155 expression was increased in unstimulated hCMEC/D3 cells, but not in cytokine-stimulated endothelium. These data suggest that miR-155, miR-126 and miR-126* modulate leukocyte adhesion on human brain microvascular endothelium. To our knowledge, this study is the first to report a role for miR-155 and miR-l26* in the interactions between human brain endothelium and immune cells and the first to confirm the regulation of VCAM1 and CCL2 by miR-126 in brain endothelium

Gut microbiota diversity and T1DM onset: Preliminary data of a case-control study

Type-1 diabetes incidence is increasing during the last decades. Recently, a role of microbiota alteration is proposed as pre-diabetic and diabetic risk factor. A bicentric case-control study is in progress in Northern Italy. Here preliminary results are shown. The microbiome clusterization showed a division between cases and controls even if fingerprint profiles are heterogenic. Methanobrevibacter smithii is highly present only in few patients. The diversity index and the microorganism sequenced in cases and controls, seems to be quite dissimilar. The conclusive results could show a significant predictive value for the bio-indicators evaluated. Keywords: Type 1 diabetes mellitus, Microbiota, Children, Methanobrevibacter smithii, qRT-PC

Cannabinoids reduce ErbB2-driven breast cancer progression through Akt inhibition.

RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.BACKGROUND: ErbB2-positive breast cancer is characterized by highly aggressive phenotypes and reduced responsiveness to standard therapies. Although specific ErbB2-targeted therapies have been designed, only a small percentage of patients respond to these treatments and most of them eventually relapse. The existence of this population of particularly aggressive and non-responding or relapsing patients urges the search for novel therapies. The purpose of this study was to determine whether cannabinoids might constitute a new therapeutic tool for the treatment of ErbB2-positive breast tumors. We analyzed their antitumor potential in a well established and clinically relevant model of ErbB2-driven metastatic breast cancer: the MMTV-neu mouse. We also analyzed the expression of cannabinoid targets in a series of 87 human breast tumors. RESULTS: Our results show that both Delta9-tetrahydrocannabinol, the most abundant and potent cannabinoid in marijuana, and JWH-133, a non-psychotropic CB2 receptor-selective agonist, reduce tumor growth, tumor number, and the amount/severity of lung metastases in MMTV-neu mice. Histological analyses of the tumors revealed that cannabinoids inhibit cancer cell proliferation, induce cancer cell apoptosis, and impair tumor angiogenesis. Cannabinoid antitumoral action relies, at least partially, on the inhibition of the pro-tumorigenic Akt pathway. We also found that 91% of ErbB2-positive tumors express the non-psychotropic cannabinoid receptor CB2. CONCLUSIONS: Taken together, these results provide a strong preclinical evidence for the use of cannabinoid-based therapies for the management of ErbB2-positive breast cancer

Risk factors for type 1 diabetes, including environmental, behavioural and gut microbial factors: a case–control study

Type 1 diabetes (T1D) is a common autoimmune disease that is characterized by insufficient insulin production. The onset of T1D is the result of gene-environment interactions. Sociodemographic and behavioural factors may contribute to T1D, and the gut microbiota is proposed to be a driving factor of T1D. An integrated preventive strategy for T1D is not available at present. This case-control study attempted to estimate the exposure linked to T1D to identify significant risk factors for healthy children. Forty children with T1D and 56 healthy controls were included in this study. Anthropometric, socio-economic, nutritional, behavioural, and clinical data were collected. Faecal bacteria were investigated by molecular methods. The findings showed, in multivariable model, that the risk factors for T1D include higher Firmicutes levels (OR 7.30; IC 2.26-23.54) and higher carbohydrate intake (OR 1.03; IC 1.01-1.05), whereas having a greater amount of Bifidobacterium in the gut (OR 0.13; IC 0.05 - 0.34) was a protective factor for T1D. These findings may facilitate the development of preventive strategies for T1D, such as performing genetic screening, characterizing the gut microbiota, and managing nutritional and social factors

IQGAP1 and NWASP promote human cancer cell dissemination and metastasis by regulating β1-integrin via FAK and MRTF/SRF

Attachment of circulating tumor cells to the endothelial cells (ECs) lining blood vessels is a critical step in cancer metastatic colonization, which leads to metastatic outgrowth. Breast and prostate cancers are common malignancies in women and men, respectively. Here, we observe that β1-integrin is required for human prostate and breast cancer cell adhesion to ECs under shear-stress conditions in vitro and to lung blood vessel ECs in vivo. We identify IQGAP1 and neural Wiskott-Aldrich syndrome protein (NWASP) as regulators of β1-integrin transcription and protein expression in prostate and breast cancer cells. IQGAP1 and NWASP depletion in cancer cells decreases adhesion to ECs in vitro and retention in the lung vasculature and metastatic lung nodule formation in vivo. Mechanistically, NWASP and IQGAP1 act downstream of Cdc42 to increase β1-integrin expression both via extracellular signal-regulated kinase (ERK)/focal adhesion kinase signaling at the protein level and by myocardin-related transcription factor/serum response factor (SRF) transcriptionally. Our results identify IQGAP1 and NWASP as potential therapeutic targets to reduce early metastatic dissemination

Brain endothelial miR-146a negatively modulates T-cell adhesion through repressing multiple targets to inhibit NF-κB activation.

Pro-inflammatory cytokine-induced activation of nuclear factor, NF-κB has an important role in leukocyte adhesion to, and subsequent migration across, brain endothelial cells (BECs), which is crucial for the development of neuroinflammatory disorders such as multiple sclerosis (MS). In contrast, microRNA-146a (miR-146a) has emerged as an anti-inflammatory molecule by inhibiting NF-κB activity in various cell types, but its effect in BECs during neuroinflammation remains to be evaluated. Here, we show that miR-146a was upregulated in microvessels of MS-active lesions and the spinal cord of mice with experimental autoimmune encephalomyelitis. In vitro, TNFα and IFNγ treatment of human cerebral microvascular endothelial cells (hCMEC/D3) led to upregulation of miR-146a. Brain endothelial overexpression of miR-146a diminished, whereas knockdown of miR-146a augmented cytokine-stimulated adhesion of T cells to hCMEC/D3 cells, nuclear translocation of NF-κB, and expression of adhesion molecules in hCMEC/D3 cells. Furthermore, brain endothelial miR-146a modulates NF-κB activity upon cytokine activation through targeting two novel signaling transducers, RhoA and nuclear factor of activated T cells 5, as well as molecules previously identified, IL-1 receptor-associated kinase 1, and TNF receptor-associated factor 6. We propose brain endothelial miR-146a as an endogenous NF-κB inhibitor in BECs associated with decreased leukocyte adhesion during neuroinflammation

Combined fit to the spectrum and composition data measured by the Pierre Auger Observatory including magnetic horizon effects

The measurements by the Pierre Auger Observatory of the energy spectrum and mass composition of cosmic rays can be interpreted assuming the presence of two extragalactic source populations, one dominating the flux at energies above a few EeV and the other below. To fit the data ignoring magnetic field effects, the high-energy population needs to accelerate a mixture of nuclei with very hard spectra, at odds with the approximate E$^{-2}$ shape expected from diffusive shock acceleration. The presence of turbulent extragalactic magnetic fields in the region between the closest sources and the Earth can significantly modify the observed CR spectrum with respect to that emitted by the sources, reducing the flux of low-rigidity particles that reach the Earth. We here take into account this magnetic horizon effect in the combined fit of the spectrum and shower depth distributions, exploring the possibility that a spectrum for the high-energy population sources with a shape closer to E$^{-2}$ be able to explain the observations

Correction to: Two years later: Is the SARS-CoV-2 pandemic still having an impact on emergency surgery? An international cross-sectional survey among WSES members

Background: The SARS-CoV-2 pandemic is still ongoing and a major challenge for health care services worldwide. In the first WSES COVID-19 emergency surgery survey, a strong negative impact on emergency surgery (ES) had been described already early in the pandemic situation. However, the knowledge is limited about current effects of the pandemic on patient flow through emergency rooms, daily routine and decision making in ES as well as their changes over time during the last two pandemic years. This second WSES COVID-19 emergency surgery survey investigates the impact of the SARS-CoV-2 pandemic on ES during the course of the pandemic. Methods: A web survey had been distributed to medical specialists in ES during a four-week period from January 2022, investigating the impact of the pandemic on patients and septic diseases both requiring ES, structural problems due to the pandemic and time-to-intervention in ES routine. Results: 367 collaborators from 59 countries responded to the survey. The majority indicated that the pandemic still significantly impacts on treatment and outcome of surgical emergency patients (83.1% and 78.5%, respectively). As reasons, the collaborators reported decreased case load in ES (44.7%), but patients presenting with more prolonged and severe diseases, especially concerning perforated appendicitis (62.1%) and diverticulitis (57.5%). Otherwise, approximately 50% of the participants still observe a delay in time-to-intervention in ES compared with the situation before the pandemic. Relevant causes leading to enlarged time-to-intervention in ES during the pandemic are persistent problems with in-hospital logistics, lacks in medical staff as well as operating room and intensive care capacities during the pandemic. This leads not only to the need for triage or transferring of ES patients to other hospitals, reported by 64.0% and 48.8% of the collaborators, respectively, but also to paradigm shifts in treatment modalities to non-operative approaches reported by 67.3% of the participants, especially in uncomplicated appendicitis, cholecystitis and multiple-recurrent diverticulitis. Conclusions: The SARS-CoV-2 pandemic still significantly impacts on care and outcome of patients in ES. Well-known problems with in-hospital logistics are not sufficiently resolved by now; however, medical staff shortages and reduced capacities have been dramatically aggravated over last two pandemic years

Studies of the mass composition of cosmic rays and proton-proton interaction cross-sections at ultra-high energies with the Pierre Auger Observatory

In this work, we present an estimate of the cosmic-ray mass composition from the distributions of the depth of the shower maximum (Xmax) measured by the fluorescence detector of the Pierre Auger Observatory. We discuss the sensitivity of the mass composition measurements to the uncertainties in the properties of the hadronic interactions, particularly in the predictions of the particle interaction cross-sections. For this purpose, we adjust the fractions of cosmic-ray mass groups to fit the data with Xmax distributions from air shower simulations. We modify the proton-proton cross-sections at ultra-high energies, and the corresponding air shower simulations with rescaled nucleus-air cross-sections are obtained via Glauber theory. We compare the energy-dependent composition of ultra-high-energy cosmic rays obtained for the different extrapolations of the proton-proton cross-sections from low-energy accelerator data