Search results for "Catalysis"

2020

Progressive bladder cancer growth is associated with abnormal activation of the mammalian target of the rapamycin (mTOR) pathway, but treatment with an mTOR inhibitor has not been as effective as expected. Rather, resistance develops under chronic drug use, prompting many patients to lower their relapse risk by turning to natural, plant-derived products. The present study was designed to evaluate whether the natural compound, sulforaphane (SFN), combined with the mTOR inhibitor everolimus, could block the growth and proliferation of bladder cancer cells in the short- and long-term. The bladder cancer cell lines RT112, UMUC3, and TCCSUP were exposed short- (24 h) or long-term (8 weeks) to ev…

Few layer 2D pnictogens catalyze the alkylation of soft nucleophiles with esters

2019

Group 15 elements in zero oxidation state (P, As, Sb and Bi), also called pnictogens, are rarely used in catalysis due to the difficulties associated in preparing well–structured and stable materials. Here, we report on the synthesis of highly exfoliated, few layer 2D phosphorene and antimonene in zero oxidation state, suspended in an ionic liquid, with the native atoms ready to interact with external reagents while avoiding aerobic or aqueous decomposition pathways, and on their use as efficient catalysts for the alkylation of nucleophiles with esters. The few layer pnictogen material circumvents the extremely harsh reaction conditions associated to previous superacid–catalyzed alkylations…

Tight Junctions as a Key for Pathogens Invasion in Intestinal Epithelial Cells

2021

Tight junctions play a major role in maintaining the integrity and impermeability of the intestinal barrier. As such, they act as an ideal target for pathogens to promote their translocation through the intestinal mucosa and invade their host. Different strategies are used by pathogens, aimed at directly destabilizing the junctional network or modulating the different signaling pathways involved in the modulation of these junctions. After a brief presentation of the organization and modulation of tight junctions, we provide the state of the art of the molecular mechanisms leading to permeability breakdown of the gut barrier as a consequence of tight junctions’ attack by pathogens, including…

A Dehydrogenase Dual Hydrogen Abstraction Mechanism Promotes Estrogen Biosynthesis: Can We Expand the Functional Annotation of the Aromatase Enzyme?

2018

Cytochrome P450 (CYP450) enzymes are involved in the metabolism of exogenous compounds and in the synthesis of signaling molecules. Among the latter, human aromatase (HA) promotes estrogen biosynthesis, which is a key pharmacological target against breast cancers. After decades of debate, interest in gaining a comprehensive picture of HA catalysis has been renewed by the recent discovery that compound I (Cpd I) is the reactive species of the peculiar aromatization step. Herein, for the first time, a complete atomic-level picture of all controversial steps of estrogen biosynthesis is presented. By performing cumulative quantum-classical molecular dynamics and metadynamics simulations of abou…

Taking Advantage of Nature’s Gift: Can Endogenous Neural Stem Cells Improve Myelin Regeneration?

2016

Irreversible functional deficits in multiple sclerosis (MS) are directly correlated to axonal damage and loss. Neurodegeneration results from immune-mediated destruction of myelin sheaths and subsequent axonal demyelination. Importantly, oligodendrocytes, the myelinating glial cells of the central nervous system, can be replaced to some extent to generate new myelin sheaths. This endogenous regeneration capacity has so far mainly been attributed to the activation and recruitment of resident oligodendroglial precursor cells. As this self-repair process is limited and increasingly fails while MS progresses, much interest has evolved regarding the development of remyelination-promoting strateg…

Resveratrol-Induced Temporal Variation in the Mechanical Properties of MCF-7 Breast Cancer Cells Investigated by Atomic Force Microscopy

2019

Atomic force microscopy (AFM) combined with fluorescence microscopy has been used to quantify cytomechanical modifications induced by resveratrol (at a fixed concentration of 50 &micro

Gut-CNS-Axis as Possibility to Modulate Inflammatory Disease Activity-Implications for Multiple Sclerosis.

2017

In the last decade the role of environmental factors as modulators of disease activity and progression has received increasing attention. In contrast to classical environmental modulators such as exposure to sun-light or fine dust pollution, nutrition is an ideal tool for a personalized human intervention. Various studies demonstrate a key role of dietary factors in autoimmune diseases including Inflammatory Bowel Disease (IBD), rheumatoid arthritis or inflammatory central nervous system (CNS) diseases such as Multiple Sclerosis (MS). In this review we discuss the connection between diet and inflammatory processes via the gut–CNS-axis. This axis describes a bi-directional communication syst…

2020

The periodontal ligament (PDL) is exposed to different kinds of mechanical stresses such as bite force or orthodontic tooth movement. A simple and efficient model to study molecular responses to mechanical stress is the application of compressive force onto primary human periodontal ligament fibroblasts via glass disks. Yet, this model suffers from the need for primary cells from human donors which have a limited proliferative capacity. Here we show that an immortalized cell line, PDL-hTERT, derived from primary human periodontal ligament fibroblasts exhibits characteristic responses to glass disk-mediated compressive force resembling those of primary cells. These responses include inductio…

Immune response to tick-borne hemoparasites: Host adaptive immune response mechanisms as potential targets for therapies and vaccines

2020

This article belongs to the Section Molecular Immunology.

Proton Leakage Is Sensed by IM30 and Activates IM30-Triggered Membrane Fusion

2020

The inner membrane-associated protein of 30 kDa (IM30) is crucial for the development and maintenance of the thylakoid membrane system in chloroplasts and cyanobacteria. While its exact physiological function still is under debate, it has recently been suggested that IM30 has (at least) a dual function, and the protein is involved in stabilization of the thylakoid membrane as well as in Mg2+-dependent membrane fusion. IM30 binds to negatively charged membrane lipids, preferentially at stressed membrane regions where protons potentially leak out from the thylakoid lumen into the chloroplast stroma or the cyanobacterial cytoplasm, respectively. Here we show in vitro that IM30 membrane binding…