A Water-Soluble Manganese(II) Octanediaoate/Phenanthroline Complex Acts as an Antioxidant and Attenuates Alpha-Synuclein Toxicity

The overproduction of reactive oxygen species (ROS) induces oxidative stress, a well-known process associated with aging and several human pathologies, such as cancer and neurodegenerative diseases. A large number of synthetic compounds have been described as antioxidant enzyme mimics, capable of eliminating ROS and/or reducing oxidative damage. In this study, we investigated the antioxidant activity of a water-soluble 1,10-phenantroline-octanediaoate Mn2+-complex on cells under oxidative stress, and assessed its capacity to attenuate alpha-synuclein (aSyn) toxicity and aggregation, a process associated with increased oxidative stress. This Mn2+-complex exhibited a significant antioxidant potential, reducing intracelular oxidation and increasing oxidative stress resistance in S. cerevisiae cells and in vivo, in G. mellonella, increasing the activity of the intracellular antioxidant enzymes superoxide dismutase and catalase. Strikingly, the Mn2+-complex reduced both aSyn oligomerization and aggregation in human cell cultures and, using NMR and DFT/molecular docking we confirmed its interaction with the C-terminal region of aSyn. In conclusion, the Mn2+-complex appears as an excellent lead for the design of new phenanthroline derivatives as alternative compounds for preventing oxidative damages and oxidative stress - related diseases.

A yeast with muscle does not run faster: full humanization of the glycolytic pathway in Saccharomyces cerevisiae

While transplantation of single genes in yeast plays a key role in elucidating gene functionality in metazoans, technical challenges hamper the humanization of full pathways and processes. Empowered by advances in synthetic biology, this study demonstrates the feasibility and implementation of full humanization of glycolysis in yeast. Single gene and full pathway transplantation revealed the remarkable conservation of both glycolytic and moonlighting functions and, combined with evolutionary strategies, brought to light novel, context-dependent responses. Remarkably, human hexokinase 1 and 2, but not 4, required mutations in their catalytic or allosteric sites for functionality in yeast, while hexokinase 3 was unable to complement its yeast ortholog. Comparison with human tissues cultures showed the preservation of turnover numbers of human glycolytic enzymes in yeast and human cell cultures. This demonstration of transplantation of an entire, essential pathway paves the way to the establishment of species, tissue and disease-specific metazoan models.

Two engineered AAV capsid variants for efficient transduction of human cortical neurons directly converted from iPSC

Recombinant adeno-associated virus (AAV) is the most widely used vector for gene therapy in clinical trials. To increase transduction efficiency and specificity, novel engineered AAV variants with modified capsid sequences are evaluated in human cell cultures and non-human primates. In the present study, we tested two novel AAV capsid variants, AAV2-NNPTPSR and AAV9-NVVRSSS, in human cortical neurons, which were directly converted from human induced pluripotent stem cells and cocultured with rat primary astrocytes. AAV2-NNPTPSR variant efficiently transduced both induced human cortical glutamatergic neurons and induced human cortical GABAergic interneurons. By contrast, AAV9-NVVRSSS variant transduced both induced human cortical neurons and cocultured rat primary astrocytes. High viral titers (1x10E5 viral genomes per cell) caused a significant decrease in viability of induced human cortical neurons. Low viral titers (1x10E4 viral genomes per cell) lead to a significant increase in the neuronal activity marker c-Fos in transduced human neurons following treatment with a potassium channel blocker, which may indicate functional alterations induced by viral transduction and/or transgene expression.

Recovery of Bioactive Compounds from Strawberry (Fragaria × ananassa) Pomace by Conventional and Pressurized Liquid Extraction and Assessment Their Bioactivity in Human Cell Cultures

Pressing strawberries for juice generates large amounts of pomace, containing valuable nutrients and therefore requiring more systematic studies for their valorization. This study compared conventional solid-liquid (SLE) and pressurized liquid (PLE) extractions with ethanol (EtOH) and H2O for the recovery of bioactive compounds from strawberry pomace. The composition and bioactivities of the products obtained were evaluated. Among 15 identified compounds, quercetin-3-glucuronide, kaempferol-3-glucuronide, tiliroside, ellagic, malic, succinic, citric and p-coumaric acids were the most abundant constituents in strawberry pomace extracts. SLE-EtOH and PLE-H2O extracts possessed strong antioxidant capacity in DPPH• and ABTS•+ scavenging and oxygen radical absorbance capacity (ORAC) assays. Cytotoxicity, antiproliferative and cellular antioxidant activities in human cells of PLE-EtOH and PLE-H2O extracts were also evaluated. PLE-EtOH and PLE-H2O extracts possessed strong antioxidant activity, protecting Caco-2 cells upon stress stimuli, while PLE-EtOH extract showed higher antiproliferative activity with no cytotoxicity associated. In general, the results obtained revealed that properly selected biorefining schemes enable obtaining from strawberry pomace high nutritional value functional ingredients for foods and nutraceuticals.

Assessment of genotoxic and mutagenic effects of food products by bioassay methods

The current state of studies on application and safety of food additives in various technologies for food production is examined. Considerable attention should be given to studies dedicated to analysis of food safety criteria due to a possibility of appearance of adverse consequences for human health and the trend towards increasing life quality. Special emphasis is placed on such parameters as genotoxicity and mutagenicity. It is shown that the most rapid and convenient tool for complex monitoring of product toxicity can be the bioassay procedure. Based on the review of the literature on bioassays for edible meat and meat products, canned foods, carbonated soft drinks, beer, milk and milk containing products as well as seasonings, the authors show that above mentioned products had the cyto- and genotoxic potential when tested on animal and human cell cultures, microorganisms and plants. With that, it was found that a list of relevant publications is quite small despite a significant growth in scientific research dedicated to food toxicity assessment using bioassays. A review on the conducted research on assessment of genotoxic and mutagenic effects of foods by bioassay methods will make it possible to extend the understanding of the processes and mechanisms of this toxicity and form more rational concept of consumption.

Therapeutic application of alpha-1-antitrypsin in COVID-19

Rationale: The treatment options for COVID-19 patients are sparse and do not show sufficient efficacy. Alpha-1-antitrypsin (AAT) is a multi-functional host-defense protein with anti-proteolytic and anti-inflammatory activities. Objectives: The aim of the present study was to evaluate whether AAT is a suitable candidate for treatment of COVID-19. Methods: AAT and inflammatory markers were measured in the serum of COVID-19 patients. Human cell cultures were employed to determine the cell-based anti-protease activity of AAT and to test whether AAT inhibits the host cell entry of vesicular stomatitis virus (VSV) particles bearing the spike (S) protein of SARS-CoV-2 and the replication of authentic SARS-CoV-2. Inhaled and / or intravenous AAT was applied to nine patients with mild-to-moderate COVID-19. Measurements and Main Results: The serum AAT concentration in COVID-19 patients was increased as compared to control patients. The relative AAT concentrations were decreased in severe COVID-19 or in non-survivors in ratio to inflammatory blood biomarkers. AAT inhibited serine protease activity in human cell cultures, the uptake of VSV-S into airway cell lines and the replication of SARS-CoV-2 in human lung organoids. All patients, who received AAT, survived and showed decreasing respiratory distress, inflammatory markers, and viral load. Conclusion: AAT has anti-SARS-CoV-2 activity in human cell models, is well tolerated in patients with COVID-19 and together with its anti-inflammatory properties might be a good candidate for treatment of COVID-19.

Complete Genome Sequence of Sphingomonas paucimobilis Strain Kira, Isolated from Human Neuroblastoma SH-SY5Y Cell Cultures Supplemented with Retinoic Acid

ABSTRACT Because of its small size, Gram-negative Sphingomonas paucimobilis can pose a risk of nosocomial infection. We report the complete circular genome sequence of S. paucimobilis strain Kira, which was isolated from retinoic acid-supplemented SH-SY5Y human cell cultures, to be 3,917,410 bp (G+C content, 65.7%; 3,672 protein-coding sequences), with two plasmids (79,575 bp and 44,333 bp).

Electrophysiological Analysis of Brain Organoids: Current Approaches and Advancements

Brain organoids, or cerebral organoids, have become widely used to study the human brain in vitro. As pluripotent stem cell-derived structures capable of self-organization and recapitulation of physiological cell types and architecture, brain organoids bridge the gap between relatively simple two-dimensional human cell cultures and non-human animal models. This allows for high complexity and physiological relevance in a controlled in vitro setting, opening the door for a variety of applications including development and disease modeling and high-throughput screening. While technologies such as single cell sequencing have led to significant advances in brain organoid characterization and understanding, improved functional analysis (especially electrophysiology) is needed to realize the full potential of brain organoids. In this review, we highlight key technologies for brain organoid development and characterization, then discuss current electrophysiological methods for brain organoid analysis. While electrophysiological approaches have improved rapidly for two-dimensional cultures, only in the past several years have advances been made to overcome limitations posed by the three-dimensionality of brain organoids. Here, we review major advances in electrophysiological technologies and analytical methods with a focus on advances with applicability for brain organoid analysis.

TOXIC EFFECTS OF POTENTIAL AGENTS FOR BORNEUTRON CAPTURE THERAPY

The aim of the investigation was to study the cytotoxicity of boron-containing compounds intended for boron neutron capture therapy of oncopathology. The studies were performed on human cell cultures. The results obtained indicate a low toxic effect of the GL-57 sample as compared to the GL-63 sample.

Meta-Analysis of Transcriptome Data Detected New Potential Players in Response to Dioxin Exposure in Humans

Dioxins are one of the most potent anthropogenic poisons, causing systemic disorders in embryonic development and pathologies in adults. The mechanism of dioxin action requires an aryl hydrocarbon receptor (AhR), but the downstream mechanisms are not yet precisely clear. Here, we performed a meta-analysis of all available transcriptome datasets taken from human cell cultures exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Differentially expressed genes from different experiments overlapped partially, but there were a number of those genes that were systematically affected by TCDD. Some of them have been linked to toxic dioxin effects, but we also identified other attractive targets. Among the genes that were affected by TCDD, there are functionally related gene groups that suggest an interplay between retinoic acid, AhR, and Wnt signaling pathways. Next, we analyzed the upstream regions of differentially expressed genes and identified potential transcription factor (TF) binding sites overrepresented in the genes responding to TCDD. Intriguingly, the dioxin-responsive element (DRE), the binding site of AhR, was not overrepresented as much as other cis-elements were. Bioinformatics analysis of the AhR binding profile unveils potential cooperation of AhR with E2F2, CTCFL, and ZBT14 TFs in the dioxin response. We discuss the potential implication of these predictions for further dioxin studies.