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Κυριακή 14 Ιουλίου 2019

Molecular and Cellular Biochemistry

Co-treatment with interferon-γ and 1-methyl tryptophan ameliorates cardiac fibrosis through cardiac myofibroblasts apoptosis

Abstract

Cardiac remodeling characterized by cardiac fibrosis is a pathologic process occurring after acute myocardial infarction. Fibrosis can be ameliorated by interferon-gamma (IFN-γ), which is a soluble cytokine showing various effects such as anti-fibrosis, apoptosis, anti-proliferation, immunomodulation, and anti-viral activities. However, the role of IFN-γ in cardiac myofibroblasts is not well established. Therefore, we investigated the anti-fibrotic effects of IFN-γ in human cardiac myofibroblasts (hCMs) in vitro and whether indoleamine 2,3-dioxygenase (IDO), induced by IFN-γ and resulting in cell cycle arrest, plays an important role in regulating the biological activity of hCMs. After IFN-γ treatment, cell signaling pathways and DNA contents were analyzed to assess the biological activity of IFN-γ in hCMs. In addition, an IDO inhibitor (1-methyl tryptophan; 1-MT) was used to assess whether IDO plays a key role in regulating hCMs. IFN-γ significantly inhibited hCM proliferation, and IFN-γ-induced IDO expression caused cell cycle arrest in G0/G1 through tryptophan depletion. Moreover, IFN-γ treatment gradually suppressed the expression of α-smooth muscle actin. When IDO activity was inhibited by 1-MT, marked apoptosis was observed in hCMs through the induction of interferon regulatory factor, Fas, and Fas ligand. Our results suggest that IFN-γ plays key roles in anti-proliferative and anti-fibrotic activities in hCMs and further induces apoptosis via IDO inhibition. In conclusion, co-treatment with IFN-γ and 1-MT can ameliorate fibrosis in cardiac myofibroblasts through apoptosis.

MicroRNA-132-3p represses Smad5 in MC3T3-E1 osteoblastic cells under cyclic tensile stress

Abstract

MicroRNAs (miRNAs) regulate osteogenic differentiation of bone cells, which has applications in orthodontics. Here we evaluated the miRNA expression profile of MC3T3-E1 osteoblasts under cyclic tensile stress with chip technology and found that miR-132-3p was up-regulated by 12% cyclic tensile stress. Alkaline phosphatase activity and osteocalcin expression in MC3T3-E1 cells were decreased under these conditions. Smad2 and Smad5 were identified as potential target genes of miR-132-3p. Native and phosphorylated Smad2 and Smad5 expression was negatively correlated with miR-132-3p levels in the cells under cyclic stretch; however, only Smad5 protein level was reduced upon miR-132-3p overexpression. The luciferase reporter assay confirmed a direct interaction between miR-132-3p and Smad5. Thus, miR-132-3p maybe regulates osteoblast differentiation via Smad5 in response to cyclic tensile stress.

Exosomes derived from microRNA-101-3p-overexpressing human bone marrow mesenchymal stem cells suppress oral cancer cell proliferation, invasion, and migration

Abstract

Dysregulation of microRNAs (miRNAs) has been found to disrupt the progression of oral cancer. However, which miRNAs are most effective against oral cancer and how these miRNAs should be delivered are major unanswered problems. We aimed at investigating if human bone marrow mesenchymal stem cells (hBMSCs)-derived exosomes affect oral cancer development, and the potential regulatory mechanism associated with COL10A1 and miR-101-3p. COL10A1 was upregulated, while miR-101-3p was downregulated in oral cancer, and miR-101-3p targeted COL10A1 as verified by dual-luciferase reporter gene assay. Meanwhile, exosomes derived from hBMSCs were isolated and then co-cultured with oral cancer cells to identify the role of exosomes, and the results suggested that hBMSCs-derived exosomes overexpressing miR-101-3p inhibited oral cancer progression. Furthermore, tumorigenicity assay in nude mice further confirmed the inhibitory effects of hBMSCs-derived exosomes, loaded with miR-101-3p, on oral cancer, which provides a new theoretical basis in the treatment of oral cancer.

Chronic effects of platinum(IV) complex and its diamine ligand on rat heart function: comparison with cisplatin

Abstract

The aim of the present study was to compare the cardiodynamic parameters in the isolated rat heart in animals chronically treated with cisplatin, platinum(IV) complex and its diamine ligand. Sixty Wistar albino rats (8 weeks old) were divided into five groups: three experimental and two control groups. Animals in all groups were treated with a dose of 4 mg/kg body weight once a week for 4 weeks with different substances; experimental groups received cisplatin, ligand and octahedral platinum(IV) complex, and control groups received saline and dimethyl sulfoxide. After sacrificing the animals, hearts were isolated and perfused according to the Langendorff technique at gradually increased coronary perfusion pressures (40–120 cmH2O). The following parameters of cardiac function were continuously recorded: maximum and minimum rate of change of pressure in the left ventricle, systolic and diastolic left ventricular pressure, heart rate and coronary flow. The results showed statistically significant differences between all experimental groups in maximum and minimum rate of pressure development as well as in systolic pressure of the left ventricle, whereas cisplatin, ligand and the platinum(IV) complex had effects on heart contractility without significant influences on coronary circulation. The findings of the present study could be important for a better understanding of anticancer drug cardiac side effects. Our results indicate that compared to cisplatin as a “gold standard”, novel platinum complexes and ligands do not possess fewer negative effects on the heart, indicating insufficient safety for their usage in terms of affecting cardiac function, a result that can be of great interest for further investigations.

Berberine enhances posttranslational protein stability of p21/cip1 in breast cancer cells via down-regulation of Akt

Abstract

Berberine has shown anticancer properties and has potential for a chemopreventive and/or chemotherapeutic agent for breast cancer. Berberine showed cytotoxicity to breast cancer cells, with an increase in the levels of p21/cip1 and p27/kip1, cyclin-dependent kinase inhibitors (CDKI), but mechanisms involved in up-regulating these molecules are largely unknown. Herein, we studied the key regulatory mechanisms involved in berberine-mediated up-regulation of p21/cip1 and p27/kip1. Berberine treatment for 24 and 48 h decreased the number of cells by 44–84% (P < 0.0001) and 38–78% (P < 0.0001), and increased cell death by 12–17% (P < 0.005) and 38–78% (P < 0.0001) in MCF-7 and MDA-MB-231 cells, respectively. Cells were arrested in G1 phase by berberine which was accompanied with up-regulation of mRNA and protein level of both p21/cip1 and p27/kip1. Berberine decreased the expression of protein levels of cyclin D1, cyclin E, CDK2, CDK4, and CDK6 to cause G1 phase arrest. Berberine caused nuclear localization of p21/cip1 in both the cell lines. Our data for the first time showed that the post-translational stability of both the proteins was strongly increased by berberine as examined by cycloheximide chase assay. Inhibition of Akt was associated with berberine-mediated up-regulation of p21/cip1 and also led to a decrease in cell viability accompanied with significant G1 phase cell cycle arrest. Our study revealed that berberine not only up-regulates mRNA and protein levels of p21/cip1 and p27/kip1 but also increases their nuclear localization and post-translational protein stability. Further, Akt inhibition was found to mediate berberine-mediated up-regulation of p21/cip1 but not the p27/kip1.

Novel insights of elevated systemic levels of bisphenol-A (BPA) linked to poor glycemic control, accelerated cellular senescence and insulin resistance in patients with type 2 diabetes

Abstract

There is a striking interaction of genes and environment in the etiology of type 2 diabetes mellitus (T2DM). While endocrine disrupting chemicals (EDCs) like bisphenol-A (BPA) have received special attention for their mechanistic role in metabolic disruption, there is a lack of clinically relevant data on BPA levels in Asian Indians, a population which is more susceptible to type 2 diabetes mellitus (T2DM) and cardiovascular diseases. Therefore, we measured systemic levels of BPA in patients with T2DM compared to individuals with normal glucose tolerance (n = 30 each). Serum BPA levels were estimated using ELISA kit, and biochemical determinations were done by standard protocols. Peripheral blood mononuclear cells (PBMCs) were used to profile the gene expression alterations with special reference to inflammation, estrogen receptors, and cellular senescence in these subjects. Serum levels of BPA were significantly higher in patients with T2DM compared to control individuals and positively correlated to poor glycemic control and insulin resistance. Patients with T2DM exhibited significantly elevated mRNA levels of senescence (GLB1, p16, p21, and p53) and inflammatory (IL6 and TNF-α) markers, shortened telomeres as well as elevated levels of estrogen-related receptor gamma (ERRγ), a recently identified receptor for BPA. BPA levels were positively correlated to senescence indicators, inflammatory markers and ERRγ and negatively correlated to telomere length. Our study is the first data in the clinical diabetes setting to demonstrate an association of increased BPA levels with cellular senescence, proinflammation, poor glycemic control, insulin resistance, and shortened telomeres in patients with T2DM.

Graphical abstract


Repetitive transcranial magnetic stimulation protects mice against 6-OHDA-induced Parkinson’s disease symptoms by regulating brain amyloid β 1–42 level

Abstract

Repetitive transcranial magnetic stimulation (rTMS) is a technique protecting neurons against diverse neurodegenerative disorders by delivering magnetic stimuli into the brain through the intact scalp. In the current study, the protection effect of rTMS on Parkinson’s disease (PD) and the associated mechanism driving the treatment were explored. The PD symptoms were induced using 6-OHDA in mice, and the effect of rTMS of two frequencies (1 Hz and 10 Hz) on the cognitive behaviors and neuron viability was detected. Afterwards, the level of Aβ1–42 and activity of MKK7-ERK-Fos-APP axis under the administration of rTMS were recorded as well. The intracranial injection of 6-OHDA impaired the cognitive behaviors of the mice in the test of Morris water maze as well as reducing the viability and number of neurons in PD mice. After the treatment of rTMS of both frequencies, the cognitive function of mice was improved and the neuron viability and number were restored in mice brain tissues. The administration of rTMS also increased the cerebrospinal fluid (CSF) level of Aβ1–42 in PD mice, which was accompanied by the suppressed levels of p-MKK7, p-ERK1/2, p–c-Fos, and APP. Moreover, the effect of rTMS on mice nerve system was all exerted in a frequency-dependent manner. In conclusion, the findings outlined in the current study affirmed the protection effect of rTMS against PD. The anti-PD function of rTMS was associated with the suppression of MKK7-ERK-Fos-APP axis, which subsequently resulted in the increased CSF Aβ1–42 level and decreased brain Aβ1–42 level.

FT Raman spectroscopy in the evaluation of biomarkers of normal and pathological placenta tissue

Abstract

The basic precondition of proper intrauterine growth is appropriate supply of nutrients transported through placenta. Placenta capacity in the scope of transportation is dependent on transport systems and the structure of the basement membrane and syncytiotrophoblast microvillous membrane. The present pilot study demonstrates preliminary results of the analysis of placenta structure in the course of selected pathologies by FT Raman spectroscopy analysis. The observed changes of the molecular structure in the so-called average spectra, independent of methodical processing, may be an indicator of the efficiency of transportation controlled by syncytiotrophoblast. In particular, an increase in the intensity of dispersion and transfer within the frequency of 3425–3300 cm−1 demonstrate the dynamics of the interaction in the scope of hydrogen bonds in healthy tissues. Changes in the molecular structure within the frequency of 950–750 cm−1 and conformational changes within disulphide bonds differentiate the healthy tissue from the pathological one. Changes in the molecular structure observed in the FTR spectra are a spectroscopic image of placenta functions in the course of various pathologies. They also document a complex goal of our research that is finding spectroscopic biomarkers of regular and pathological placental tissue.

Biological effects of cyclosporin A on CD3 − CD161 + and CD3 + CD161 + lymphocytes

Abstract

Cyclosporin A (CSA) is a widely used drug to prevent the immune cell function. It is well known that CSA blocks transcription of cytokine genes in activated T cells. The connection between T cells and CSA has been well established. However, the effect of CSA on natural killer (NK) cells is not thoroughly understood. Therefore, in the present study, splenocytes and peripheral blood mononuclear cells (PBMCs) were treated with CSA in the presence of concanavalin A (Con A) or interleukin-2 (IL-2). CSA at higher concentrations induces apoptosis and inhibition of proliferation, while lower concentrations showed synergistically enhanced proliferation in splenocytes and PBMCs. Further, CSA favored the in vitro conversion of CD3+CD161+ cells. Splenocytes and PBMC were found to have synergistic proliferation with Con A, and PBMC exhibited significantly higher expression of NKp30, NKp44, and granzyme B along with enhanced cytotoxicity against K-562 cells in CSA-treated animals. Proliferation assay also showed that proliferation of CD161+ cells was higher in CSA-treated animals. Collectively, our results suggest that CSA differentially influences the population, function, and expression of the NK cell phenotype.

Biochemical, machine learning and molecular approaches for the differential diagnosis of Mucopolysaccharidoses

Abstract

This study was aimed to construct classification and regression tree (CART) model of glycosaminoglycans (GAGs) for the differential diagnosis of Mucopolysaccharidoses (MPS). Two-dimensional electrophoresis and liquid chromatography–tandem mass spectrometry (LC–MS/MS) were used for the qualitative and quantitative analysis of GAGs. Specific enzyme assays and targeted gene sequencing were performed to confirm the diagnosis. Machine learning tools were used to develop CART model based on GAG profile. Qualitative and quantitative CART models showed 96.3% and 98.3% accuracy, respectively, in the differential diagnosis of MPS. The thresholds of different GAGs diagnostic of specific MPS types were established. In 60 MPS positive cases, 46 different mutations were identified in six specific genes. Among 31 different mutations identified in IDUA, nine were nonsense mutations and two were gross deletions while the remaining were missense mutations. In IDS gene, four missense, two frameshift, and one deletion were identified. In NAGLU gene, c.1693C > T and c.1914_1914insT were the most common mutations. Two ARSB, one case each of SGSH and GALNS mutations were observed. LC–MS/MS-based GAG pattern showed higher accuracy in the differential diagnosis of MPS. The mutation spectrum of MPS, specifically in IDUA and IDSgenes, is highly heterogeneous among the cases studied.

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