11 research outputs found
Estrogen Receptor Subtypes Elicit a Distinct Gene Expression Profile of Endothelial-Derived Factors Implicated in Atherosclerotic Plaque Vulnerability
In the presence of established atherosclerosis, estrogens are potentially harmful. MMP-2 and MMP-9, their inhibitors (TIMP-2 and TIMP-1), RANK, RANKL, OPG, MCP-1, lysyl oxidase (LOX), PDGF-β, and ADAMTS-4 play critical roles in plaque instability/rupture. We aimed to investigate (i) the effect of estradiol on the expression of the abovementioned molecules in endothelial cells, (ii) which type(s) of estrogen receptors mediate these effects, and (iii) the role of p21 in the estrogen-mediated regulation of the aforementioned factors. Human aortic endothelial cells (HAECs) were cultured with estradiol in the presence or absence of TNF-α. The expression of the aforementioned molecules was assessed by qRT-PCR and ELISA. Zymography was also performed. The experiments were repeated in either ERα- or ERβ-transfected HAECs and after silencing p21. HAECs expressed only the GPR-30 estrogen receptor. Estradiol, at low concentrations, decreased MMP-2 activity by 15-fold, increased LOX expression by 2-fold via GPR-30, and reduced MCP-1 expression by 3.5-fold via ERβ. The overexpression of ERα increased MCP-1 mRNA expression by 2.5-fold. In a low-grade inflammation state, lower concentrations of estradiol induced the mRNA expression of MCP-1 (3.4-fold) and MMP-9 (7.5-fold) and increased the activity of MMP-2 (1.7-fold) via GPR-30. Moreover, p21 silencing resulted in equivocal effects on the expression of the abovementioned molecules. Estradiol induced different effects regarding atherogenic plaque instability through different ERs. The balance of the expression of the various ER subtypes may play an important role in the paradoxical characterization of estrogens as both beneficial and harmful
Empagliflozin Attenuates Non-Alcoholic Fatty Liver Disease (NAFLD) in High Fat Diet Fed ApoE (-/-) Mice by Activating Autophagy and Reducing ER Stress and Apoptosis
Aims/hypothesis: SGLT-2 inhibitors (SGLT-2i) have been studied as potential treatments against NAFLD, showing varying beneficial effects. The molecular mechanisms mediating these effects have not been fully clarified. Herein, we investigated the impact of empagliflozin on NAFLD, focusing particularly on ER stress, autophagy and apoptosis. Methods: Five-week old ApoE(-/-) mice were switched from normal to a high-fat diet (HFD). After five weeks, mice were randomly allocated into a control group (HFD + vehicle) and Empa group (HFD + empagliflozin 10 mg/kg/day) for five weeks. At the end of treatment, histomorphometric analysis was performed in liver, mRNA levels of Fasn, Screbp-1, Scd-1, Ppar-γ, Pck-1, Mcp-1, Tnf-α, Il-6, F4/80, Atf4, Elf2α, Chop, Grp78, Grp94, Χbp1, Ire1α, Atf6, mTor, Lc3b, Beclin-1, P62, Bcl-2 and Bax were measured by qRT-PCR, and protein levels of p-EIF2α, EIF2a, CHOP, LC3II, P62, BECLIN-1 and cleaved CASPASE-8 were assessed by immunoblotting. Results: Empagliflozin-treated mice exhibited reduced fasting glucose, total cholesterol and triglyceride serum levels, as well as decreased NAFLD activity score, decreased expression of lipogenic enzymes (Fasn, Screbp-1c and Pck-1) and inflammatory molecules (Mcp-1 and F4/80), compared to the Control group. Empagliflozin significantly decreased the expression of ER stress molecules Grp78, Ire1α, Xbp1, Elf2α, Atf4, Atf6, Chop, P62(Sqstm1) and Grp94; whilst activating autophagy via increased AMPK phosphorylation, decreased mTOR and increased LC3B expression. Finally, empagliflozin increased the Bcl2/Bax ratio and inhibited CASPASE-8 cleavage, reducing liver cell apoptosis. Immunoblotting analysis confirmed the qPCR results. Conclusion: These novel findings indicate that empagliflozin treatment for five weeks attenuates NAFLD progression in ApoE(-/-) mice by promoting autophagy, reducing ER stress and inhibiting hepatic apoptosis
Σημασία των επαναλαμβανόμενων εξωγονιδιακών αλληλουχιών στην έκφραση των γονιδίων των σφαιρινών
The Diagnostic, Prognostic and Therapeutic Role of miRNAs in Adrenocortical Carcinoma: A Systematic Review
Adrenocortical carcinoma (ACC) is a rare endocrine malignancy with a
dismal prognosis and a high rate of recurrence and mortality.
Therapeutic options are limited. In some cases, the distinction of ACCs
from benign adrenal neoplasms with the existing widely available
pathological and histopathological tools is difficult. Thus, new
biomarkers have been tested. We conducted a review of the recent
literature on the advances of the diagnostic, prognostic and therapeutic
role of miRNAs on ACC patients. More than 10 miRNAs validated by
multiple studies were found to present a diagnostic and prognostic role
for ACC patients, from which miR-483-5p and miR-195 were the most
frequently met biomarkers. In particular, upregulation of miR-483-5p and
downregulation of miR-195 were the most commonly validated molecular
alterations. Unfortunately, data on the therapeutic role of miRNA are
still scarce and limited mainly at the experimental level. Thus, the
role of miRNA regulation in ACC remains an area of active research
Adhesion molecules and high-sensitivity C-reactive protein levels in patients with sickle cell beta-thalassaemia
Background and aim The primary symptoms of sickle cell disease (SCD)
arise from vaso-occlusive crises. The pathogenesis of these crises is
complex phenomenon where endothelial activation and damage has a major
role. Chronic inflammation also plays an important role in the
pathophysiology of SCD. We aimed to investigate endothelial activation
in Caucasian Greek patients with SCD by means of measuring adhesion
molecules and markers of inflammation. Subjects and methods Twenty-eight
patients with SCD aged 563 years were included in the study. Most of the
patients (23/28) were double heterozygotes for sickle
cell/beta-thalassaemia, while five patients (5/28) were sickle cell
homozygotes. Patients were treated with one/or more of hydroxyurea,
therapeutic phlebotomies, blood transfusion or splenectomy. Twenty
apparently healthy individuals matched for age and sex formed the
control group. Measurements of soluble intercellular adhesion
molecule-1, (sICAM-1), soluble vascular cell adhesion molecule-1
(sVCAM-1), P-selectin, E-selectin, soluble thrombomodulin (sTM) and
high-sensitivity C-reactive protein (hs-CRP) levels were performed using
immunoassays in both patients and healthy individuals. Results We found
that all endothelial adhesion molecules and hs-CRP were significantly
increased (P < 0 center dot 001) in patients with SCD compared with
controls, while sTM levels did not differ significantly (P > 0 center
dot 05) and this increase was not influenced by the treatment.
Conclusion Our findings demonstrate the high degree of endothelial
activation and damage seen in sickle cell patients even in steady-state
condition, as well as the important chronic inflammation underlying the
pathophysiology of this widespread disease
Data on eNOS T786 and G894T polymorphisms and peripheral blood eNOS mRNA levels in Sickle Cell Disease
In this article, we present data on endothelial Nitric Oxide Synthase (eNOS) gene T786C and G894T polymorphisms in Greek steady-state Sickle Cell Disease patients in comparison to healthy controls. Moreover, eNOS mRNA levels were determined in peripheral blood samples from 18 patients and 9 controls. This article complements our recently published article named “Prognostic value of eNOS T786C and G894T polymorphisms in Sickle Cell Disease” (I. Armenis, V. Kalotychou, R. Tzanetea, Z. Kontogeorgiou, D. Anastasopoulou, M. Mantzourani, M. Samarkos, K. Pantos, K. Konstantopoulos, I. Rombos, 2016) [1]
Assessment of oxidative stress in patients with sickle cell disease: The glutathione system and the oxidant-antioxidant status
Continuous reactive oxygen species (ROS) production in individuals with
sickle cell disease (SCD) may alter their overall redox status and cause
tissue damage. The aim of this study was to evaluate oxidative stress in
patients with SCD using two new assays, FORT (free oxygen radical test)
and FORD (free oxygen radical defense) along with assessment of
glutathione system including superoxide dismutase (SOD), glutathione
reductase (GR) and glutathione peroxidase (GPx) activities, vitamins A C
and E, malondialdehyde (MDA), non-transferrin bound iron (NTBI) and
nitric oxide (NO) concentrations.
A total of 40 patients with SCD and 25 apparently healthy volunteers
(control group) were enrolled in the study. Components of glutathione
system, vitamins A, C, and E, and malondialdehyde were determined with
reverse-phase HPLC, non-transferrin bound iron (NTBI) was assessed with
atomic absorption spectroscopy using graphite furnace, superoxide
dismutase (SOD), glutathione reductase (GR) and glutathione peroxidase
(GPx) activities were determined spectrophotometrically in red cell
lysates, nitric oxide (NO) was detected colorimetrically, while FORT and
FORD using colorimetric assays, as two point-of-care tests. The findings
revealed significant impairment of the glutathione system indicated by
reduced GSH(total) (p<0.00001), GSH(reduced) (p<0.00001) and GSSG
(p>0.056) values of SCD patients compared to the control group. ROS
expressed as FORT were significantly increased (p<0.00001), while
antioxidant defense expressed as FORD was significantly reduced (p<0.02)
in SCD group compared to the control group. Age and genotype of the
patients as well as therapy of their disease appeared to play no role in
their oxidative status. (C) 2011 Elsevier Inc. All rights reserved
Time Lag between COVID-19 Diagnosis and Symptoms Onset for Different Population Groups: Evidence That Self-Testing in Schools Was Associated with Timely Diagnosis among Children
Early identification of COVID-19 cases has been vital for reducing transmission and enabling treatment. In Greece, in autumn 2021 when Delta was the predominant circulating variant, unvaccinated citizens had to be tested before attending activities, and self-testing was required twice a week for students (5–17 years). Here, we describe the time of diagnosis by age group and possible exposure to assess testing strategies (September to November 2021). Information on the presence of symptoms at the time of diagnosis was available for 69,298 cases; 24,855 (36%) were asymptomatic or tested the same day as onset (early diagnosis), 21,310 (31%) reported testing one day after, and 23,133 (33%) did so two or more days after the onset of symptoms. The median lag was 2 days (1–14). Early diagnosis significantly differed among age groups (p-value < 0.001) and was higher among children. For every one-year increase of age, the odds of an early diagnosis were reduced by 1%. Cases exposed during training activities or in settings such as accommodation centers and hospitals were more frequently diagnosed early. The percentage of persons having a positive self-test before a rapid test/PCR diagnosis ranged from 7% in the age group of 60 years and above to 86% in the age group of 5–17 years. The provision of self-tests in schools and increased testing in closed settings led to an earlier diagnosis and probably to a decreased transmission of the virus in the period during which Delta was the predominant variant in Greece. However, more effort is needed for early diagnosis of adults in the community, especially after the onset of symptoms