Trypanosomatid parasites cause diseases like African sleeping sickness, Chagas’ disease and leishmaniasis. Leishmaniasis affects about 12 million people worldwide, mostly in developing countries. Current drug treatments are inadequate due to drug toxicity and resistance.
Now, a group of European scientists has discovered new compounds that may help to fight these diseases more effectively. The project was carried out by research groups headed by Maria Paola Costi (University of Modena and Reggio Emilia, Italy), Rebecca Wade (HITS, Heidelberg Institute for Theoretical Studies, Germany) and Paul Michels (De Duve Institute , Belgium). It was supported by the Cassa di Risparmio di Modena Foundation. The research results have been published in the Journal of Medicinal Chemistry.
Trypanosomatids require folates and biopterins. These are reduced by the enzymes dihydrofolate reductase (DHFR) and pteridine reductase (PTR1). When DHFR is inhibited, DNA replication is impaired, resulting in cell death. However in trypanosomatids, PTR1 is overexpressed when DHFR is inhibited, and PTR1 can take on the role of DHFR by reducing folates, ensuring parasite survival. For the treatment of anti-parasitic diseases, it is thus necessary to block two metabolic pathways by simultaneously inhibiting DHFR and PTR1 by a single drug or a combination of two specific inhibitors. PTR1 is not present in humans and is thus an excellent target for the design of specific compounds that target the parasite.
In this project, the scientists used a virtual screening approach combined with experimental screening methodologies, to identify non-folate-like inhibitors of Leishmania PTR1. Optimization was performed in two rounds of structure-based drug design cycles to improve specificity for PTR1 and selectivity against human DHFR, resulting in 18 drug-like molecules with low micromolar affinities and high in-vitro specificity profiles. Assays of efficacy in cultured Leishmania cells showed six compounds that were active in combination with a DHFR inhibitor. One of these was also effective alone. Several of these compounds showed low toxicity profiles, and one of them is a known drug approved for treatment of diseases of the central nervous system, suggesting potential for label extension of this compound as an anti-parasitic drug candidate.The original scientific article:
http://www.unimore.itHITS (Heidelberg Institute for Theoretical Studies)
http://www.h-its.orgDe Duve Institute, Université catholique de Louvain
Dr. Peter Saueressig | idw
Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden
The pyrenoid is a carbon-fixing liquid droplet
22.09.2017 | Max-Planck-Institut für Biochemie
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
22.09.2017 | Life Sciences
22.09.2017 | Medical Engineering
22.09.2017 | Physics and Astronomy