Publications by authors named "Galkin A"

Mitochondrial function is modulated by its interaction with the endoplasmic reticulum (ER). Recent research indicates that these contacts are disrupted in familial models of amyotrophic lateral sclerosis (ALS). We report here that this impairment in the crosstalk between mitochondria and the ER impedes the use of glucose-derived pyruvate as mitochondrial fuel, causing a shift to fatty acids to sustain energy production.

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is the oldest classic model object in developmental genetics. It may seem that various structures of the fruit fly at all developmental stages have been well studied and described. However, recently we have shown that some specialized structures of the eggshell contain an amyloid fibril network.

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Alternative oxidase (AOX) is an enzyme that transfers electrons from reduced quinone directly to oxygen without proton translocation. When AOX from Ciona intestinalis is xenotopically expressed in mice, it can substitute the combined electron-transferring activity of mitochondrial complexes III/IV. Here, we used brain mitochondria from AOX-expressing mice with such a chimeric respiratory chain to study respiratory control bioenergetic mechanisms.

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Article Synopsis
  • Scientists are studying how to tell if a donated liver is healthy enough to use for transplant by looking at special markers during a process called HOPE.
  • They collected samples from livers in 10 different centers across 7 countries and found that the levels of a marker called FMN can help predict if the liver will work well after being transplanted.
  • The study showed that FMN is better at predicting liver problems compared to older methods, making it a promising tool for doctors to decide which livers are suitable for transplant.
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Mitochondrial bioenergetics in females and males is different. However, whether mitochondria from male and female brains display differences in enzymes of oxidative phosphorylation remains unknown. Therefore, we characterized mitochondrial complexes from the brains of male and female macaques (Macaca mulatta).

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Article Synopsis
  • Research shows that both Normothermic Regional Perfusion (NRP) and Hypothermic-Oxygenated-Perfusion (HOPE) improve outcomes in liver transplants from donors after circulatory death (DCD), but direct comparisons and mechanisms are not well-studied.
  • In a rat study, DCD livers experienced more damage and inflammation after NRP compared to HOPE, which resulted in better mitochondrial health and lower inflammation.
  • The findings suggest that high-risk DCD livers benefit more from HOPE, indicating a need for further clinical studies to confirm these results and improve transplant outcomes.
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Chronic activation of inflammatory pathways and suppressed interferon are hallmarks of immunosuppressive tumors. Previous studies have shown that CD11b integrin agonists could enhance anti-tumor immunity through myeloid reprograming, but the underlying mechanisms remain unclear. Herein we find that CD11b agonists alter tumor-associated macrophage (TAM) phenotypes by repressing NF-κB signaling and activating interferon gene expression simultaneously.

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Functional amyloids have been identified in a wide variety of organisms including bacteria, fungi, plants, and vertebrates. Intracellular and extracellular amyloid fibrils of different proteins perform storage, protective, structural, and regulatory functions. The structural organization of amyloid fibrils determines their unique physical and biochemical properties.

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Amyloids are fibrillar proteins with a cross-β structure. Pathological amyloids are associated with the development of a number of incurable diseases, while functional amyloids regulate vital processes. The detection of unknown amyloids in living objects is a difficult task, and therefore the question of the prevalence and biological significance of amyloids remains open.

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Metformin is an antihyperglycemic drug which is being examined as a repurposed treatment for cardiovascular disease for individuals without diabetes mellitus. Despite evidence that mitochondrial respiratory complex I is a target of metformin and inhibition of the enzyme is one of the mechanisms of its therapeutic actions, no systematic studies of the metformin effect on intact mitochondria have been reported. In the presented paper, we described the effect of metformin on respiration and ROS release by intact mitochondria from the liver and brain.

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Functional amyloids are fibrillary proteins with a cross-β structure that play a structural or regulatory role in pro- and eukaryotes. Previously, we have demonstrated that the RNA-binding FXR1 protein functions in an amyloid form in the rat brain. This RNA-binding protein plays an important role in the regulation of long-term memory, emotions, and cancer.

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Background: Signalling through platelet-derived growth factor receptor (PDGFR), colony-stimulating factor 1 receptor (CSF1R) and mast/stem cell growth factor receptor kit (c-KIT) plays a critical role in pulmonary arterial hypertension (PAH). We examined the preclinical efficacy of inhaled seralutinib, a unique small-molecule PDGFR/CSF1R/c-KIT kinase inhibitor in clinical development for PAH, in comparison to a proof-of-concept kinase inhibitor, imatinib.

Methods: Seralutinib and imatinib potency and selectivity were compared.

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In this population-based case-control study conducted in the Chelyabinsk region of Russia, we examined the distribution of HLA-A, -B, -C, -DRB1, -DQB1 and -DPB1, in a group of 100 patients with confirmed COVID-19 bilateral pneumonia. Typing was performed by NGS and statistical calculations were carried out with the Arlequin program. HLA-A, -B, -C, -DRB1, -DQB1 and -DPB1 alleles were compared between patients with COVID-19 and 99 healthy controls.

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Mitochondrial complex I is the only enzyme responsible for oxidation of matrix NADH and regeneration of NAD for catabolism. Nuclear and mtDNA mutations, assembly impairments, and enzyme damage are implicated in inherited diseases, ischemia-reperfusion injury, neurodegeneration, and tumorogenesis. Here we introduce a novel method to measure the absolute content of complex I.

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A new theoretical model of epidemic kinetics is considered, which uses elements of the physical model of the kinetics of the atomic level populations of an active laser medium as follows: a description of states and their populations, transition rates between states, an integral operator, and a source of influence. It is shown that to describe a long-term epidemic, it is necessary to use the concept of the source of infection. With a model constant source of infection, the epidemic, in terms of the number of actively infected people, goes to a stationary regime, which does not depend on the population size and the characteristics of quarantine measures.

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Mitochondrial Ca-independent phospholipase Aγ (iPLAγ/PNPLA8) was previously shown to be directly activated by HO and release free fatty acids (FAs) for FA-dependent H transport mediated by the adenine nucleotide translocase (ANT) or uncoupling protein 2 (UCP2). The resulting mild mitochondrial uncoupling and consequent partial attenuation of mitochondrial superoxide production lead to an antioxidant effect. However, the antioxidant role of iPLAγ in the brain is not completely understood.

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Pathologies associated with tissue ischemia/reperfusion (I/R) in highly metabolizing organs such as the brain and heart are leading causes of death and disability in humans. Molecular mechanisms underlying mitochondrial dysfunction during acute injury in I/R are tissue-specific, but their details are not completely understood. A metabolic shift and accumulation of substrates of reverse electron transfer (RET) such as succinate are observed in tissue ischemia, making mitochondrial complex I of the respiratory chain (NADH:ubiquinone oxidoreductase) the most vulnerable enzyme to the following reperfusion.

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The selective inhibition of RET kinase as a treatment for relevant cancer types including lung adenocarcinoma has garnered considerable interest in recent years and prompted a variety of efforts toward the discovery of small-molecule therapeutics. Hits uncovered via the analysis of archival kinase data ultimately led to the identification of a promising pyrrolo[2,3-]pyrimidine scaffold. The optimization of this pyrrolo[2,3-]pyrimidine core resulted in compound , which demonstrated potent RET kinase inhibition and robust efficacy in RET-driven tumor xenografts upon multiday dosing in mice.

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Impairments in mitochondrial energy metabolism have been implicated in human genetic diseases associated with mitochondrial and nuclear DNA mutations, neurodegenerative and cardiovascular disorders, diabetes, and aging. Alteration in mitochondrial complex I structure and activity has been shown to play a key role in Parkinson's disease and ischemia/reperfusion tissue injury, but significant difficulty remains in assessing the content of this enzyme complex in a given sample. The present study introduces a new method utilizing native polyacrylamide gel electrophoresis in combination with flavin fluorescence scanning to measure the absolute content of complex I, as well as α-ketoglutarate dehydrogenase complex, in any preparation.

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Article Synopsis
  • Prions are unique proteins that can exist in different states, some of which can be passed down through generations, specifically in yeast proteins like Sup35 and Rnq1.
  • Studies indicate that these prion states form aggregates that may have amyloid characteristics, but prior evidence in living organisms was lacking.
  • The research successfully extracted native fibrils from yeast proteins, demonstrated their amyloid properties using Congo Red dye, and showed the potential to identify new amyloids across various organisms.
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Resistance to immune checkpoint inhibitors (ICI) and other anticancer therapies is often associated with the accumulation of myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs) in the tumor microenvironment (TME). Therefore, targeting MDSC recruitment or function is of significant interest as a strategy to treat patients with ICI-resistant cancer. The migration and recruitment of MDSCs to the TME is mediated in part by the CD11b/CD18 integrin heterodimer (Mac-1; αβ), expressed on both MDSCs and TAMs.

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Background: In the developing brain, the death of immature oligodendrocytes (OLs) has been proposed to explain a developmental window for vulnerability to white matter injury (WMI). However, in neonatal mice, chronic sublethal intermittent hypoxia (IH) recapitulates the phenotype of diffuse WMI without affecting cellular viability. This work determines whether, in neonatal mice, a developmental window of WMI vulnerability exists in the absence of OLs lineage cellular death.

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Patatin-like phospholipase domain-containing protein PNPLA8, also termed Ca-independent phospholipase A2γ (iPLA2γ), is addressed to the mitochondrial matrix (or peroxisomes), where it may manifest its unique activity to cleave phospholipid side-chains from both sn-1 and sn-2 positions, consequently releasing either saturated or unsaturated fatty acids (FAs), including oxidized FAs. Moreover, iPLA2γ is directly stimulated by HO and, hence, is activated by redox signaling or oxidative stress. This redox activation permits the antioxidant synergy with mitochondrial uncoupling proteins (UCPs) or other SLC25 mitochondrial carrier family members by FA-mediated protonophoretic activity, termed mild uncoupling, that leads to diminishing of mitochondrial superoxide formation.

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