Current Evidence on Bisphenol A Exposure and the Molecular Mechanism Involved in Related Pathological Conditions

Bisphenol A (BPA) is one of the so-called endocrine disrupting chemicals (EDCs) and is thought to be involved in the pathogenesis of different morbid conditions: immune-mediated disorders, type-2 diabetes mellitus, cardiovascular diseases, and cancer. The purpose of this review is to analyze the mechanism of action of bisphenol A, with a special focus on mesenchymal stromal/stem cells (MSCs) and adipogenesis. Its uses will be assessed in various fields: dental, orthopedic, and industrial. The different pathological or physiological conditions altered by BPA and the related molecular pathways will be taken into consideration

Escape from cell death through authophagy in Human Gingival Fibroblast/Streptococcus mitis co-culture treated with Chitlac n-Ag

Since ancient times, silver has been extensively used to control infections. Silver based medical products have been proved to be effective in retarding and preventing bacterial infections (Chen et al., 2007). In order to prevent silver nanoparticles aggregation a lactose-modified chitosan was shown to be effective in stabilizing colloidal solutions of silver nanoparticles: “Chitlac-nAg” (Travan et al., 2009). Silver ions and nanoparticle are capable to destroy the bacterial cell wall by reacting with sulfhydryl groups on membrane proteins (Kruszewski et al., 2003). Since the cells are capable of internalizing nanoparticles there is the risk of a massive uptake by eukaryotic cells, which eventually leads to their death through oxidative DNA damage (Li et al. 2013) In the present work we investigated the effects of Chitlac-nAg on primary human gingival fibroblast (HGFs) co-cultured with Streptococcus mitis in the presence of saliva. HGFs were obtained from fragments of healty marginal gingival tissue, co-cultured with the clinical strain of S. mitis and treated for 24-48h with Chitlac or Chitlac-nAg. Cytotoxicity evaluated by LDH assay showed an increment in LDH release in co-culture in the presence of Chitlac n-Ag and saliva. Oxidative stress detected by means of Reactive Oxygen Species formation highlighted an early ROS presence in samples with Chitlac-nAg and saliva, but this value was similar to control after 48h; apoptotic and necrotic cells were detected by means of Annexin V/PI showing an increase in cell death in HGFs treated with Ag and saliva after 24h, and returned to basal levels after 48h; the uptake of nanoparticles by cells was determined by optical and electronic microscopy revealing the Ag uptake in vesicles. The presence of lysosomes and autophagosomes was verified by Lysotracker and by LC3 respectively. In vitro results showed that in our co-culture model, which mimics the microenvironment of the oral cavity, chitlac n-Ag does not exert cytotoxic effect towards HGFs that are able to execute a homeostasis mechanism through autophagy promoting cell survival

The Beneficial Effect of Carvacrol in HL-1 Cardiomyocytes Treated with LPS-G: Anti-Inflammatory Pathway Investigations

Carvacrol (CAR), a natural phenolic monoterpene, possesses different biological activities, such as anti-inflammatory and antioxidant activities. The current study aimed to evaluate the response of HL-1 cardiomyocytes to an inflammatory stimulus triggered by lipopolysaccharide from Porphyromonas gingivalis (LPS-G), alone or in co-treatment with CAR, to investigate the potential protective role of CAR in the inflammatory process through modulation of the TLR4/NFκB/NALP3/IL-1β pathway and ROS production. In an in vitro experiment, HL-1 cardiomyocytes were exposed to LPS-G and incubated with CAR. We evaluated the anti-inflammatory effect of CAR by the reduction in TLR4, NFκB, NALP3, and IL-1β expression using immunofluorescence staining. Western blot analysis also validated the modulation of the TLR4/NFκB/NALP3/IL-1β pathway. ROS analyses confirmed the protective effects of CAR. Our results suggest that CAR could provide a significant protection role against inflammatory stimulus generated by LPS-G, involving the suppression of the TLR4/NFκB/NALP3/IL-1β signaling pathway

Three-Dimensional Culture Systems for Dissecting Notch Signalling in Health and Disease

Three-dimensional (3D) culture systems opened up new horizons in studying the biology of tissues and organs, modelling various diseases, and screening drugs. Producing accurate in vitro models increases the possibilities for studying molecular control of cell-cell and cell-microenvironment interactions in detail. The Notch signalling is linked to cell fate determination, tissue definition, and maintenance in both physiological and pathological conditions. Hence, 3D cultures provide new accessible platforms for studying activation and modulation of the Notch pathway. In this review, we provide an overview of the recent advances in different 3D culture systems, including spheroids, organoids, and "organ-on-a-chip" models, and their use in analysing the crucial role of Notch signalling in the maintenance of tissue homeostasis, pathology, and regeneration. Keywords: 3D culture systems; Notch signalling; cancer; drug screening; microfluidics; organ-on-a-chip; organoids; regeneration; spheroids; therapy

Exosomes as Carriers for Notch Molecules

Exosomes are extracellular vesicles involved in cell-to-cell communication as well as extrusion of biological material. Using dental pulp stem cells culture as a model, we hereby describe a method for the packaging of Delta-like 4 (DLL4), a representative Notch ligand, into newly generated exosomes. We then provide methods of analysis to confirm the presence of Notch proteins and transcripts internalization and transport via exosomes

The Up-Regulation of Oxidative Stress as a Potential Mechanism of Novel MAO-B Inhibitors for Glioblastoma Treatment

Gliomas are malignant brain tumors characterized by rapid spread and growth into neighboring tissues and graded I−IV by the World Health Organization. Glioblastoma is the fastest growing and most devastating IV glioma. The aim of this paper is to evaluate the biological effects of two potent and selective Monoamine Oxidase B (MAO-B) inhibitors, Cmp3 and Cmp5, in C6 glioma cells and in CTX/TNA2 astrocytes in terms of cell proliferation, apoptosis occurrence, inflammatory events and cell migration. These compounds decrease C6 glioma cells viability sparing normal astrocytes. Cell cycle analysis, the Mitochondrial Membrane Potential (MMP) and Reactive Oxygen Species (ROS) production were detected, revealing that Cmp3 and Cmp5 induce a G1 or G2/M cell cycle arrest, as well as a MMP depolarization and an overproduction of ROS; moreover, they inhibit the expression level of inducible nitric oxide synthase 2, thus contributing to fatal drug-induced oxidative stress. Cmp5 notably reduces glioma cell migration via down-regulating Matrix Metalloproteinases 2 and 9. This study demonstrated that our novel MAO-B inhibitors increase the oxidative stress level resulting in a cell cycle arrest and markedly reduces glioma cells migration thus reinforcing the hypothesis of a critical role-played by MAO-B in mediating oncogenesis in high-grade gliomas

Inhibition of LPS-Induced Inflammatory Response of Oral Mesenchymal Stem Cells in the Presence of Galectin-3

Galectin-3 (GAL-3) is a beta-galactoside binding lectin produced by mesenchymal stem cells (MSCs) and other cell sources under inflammatory conditions. Several studies have reported that GAL-3 exerts an anti-inflammatory action, regulated by its natural ligand GAL-3 BP. In the present study, we aimed to assess the GAL-3 mediated regulation of the MSC function in an LPS-induced inflammation setting. Human gingival mesenchymal stem cells (hGMSCs) were stimulated in vitro with LPSs; the expression of TLR4, NFκB p65, MyD88 and NALP3 were assessed in the hGMSCs via immunofluorescence imaging using confocal microscopy, Western blot assay, and RT-PCR before and after the addition of GAL-3, both alone and with the addition of its inhibitors. LPSs stimulated the expression of TLR4, NFκB p65, MyD88 and NALP3 in hGMSCs, which was inhibited by GAL-3. The addition of either GAL3-BP or the antibody to GAL-3 were able to revert the GAL-3-mediated effects, restoring the expression of TLR4, NFκB p65, MyD88 and NALP3. GAL-3 induces the downregulation of the LPS-induced inflammatory program in MSCs

Microplastics Affect the Inflammation Pathway in Human Gingival Fibroblasts: A Study in the Adriatic Sea

The level of environmental microplastics in the sea is constantly increasing. They can enter the human body with food, be absorbed through the gut and have negative effects on the organism’s health after its digestion. To date, microplastics (MPs) are considered new environmental pollutants in the air sea and they are attracting wide attention. The possible toxic effects of MPs isolated at different sea depths of 1, 24 and 78 m were explored in an in vitro model of human gingival fibroblasts (hGFs). MPs isolated from the sea showed different size and were then divided into different sample groups: 1, 24 and 78 m. The results obtained revealed that MPs are able to activate the inflammatory pathway NFkB/MyD88/NLRP3. In detail, the exposure to MPs from 1 and 78 m led to increased levels of inflammatory markers NFkB, MyD88 and NLRP3 in terms of proteins and gene expression. Moreover, cells exposed to MPs showed a lower metabolic activity rate compared to unexposed cells. In conclusion, these findings demonstrate that the inflammation process is stimulated by MPs exposure, providing a new perspective to better understand the intracellular mechanism