Alterations in cancer cell metabolism have recently gained considerable attention as a possible cause of adaptation and resistance to therapy. However, the underlying molecular mechanisms, particularly in leukemia resistance occurring in the bone marrow microenvironment, remain unclear. Here, we explore the role of direct stroma-leukemia interactions and transfer of membrane vesicles along with proteins as a mechanism of stroma-driven protection. K562 CML leukemia cells and primary CD34 + CML blasts were cultured alone or co-cultured with HS-5 stromal cells to mimic the bone marrow microenvironment conditions. Imatinib treatment was used experimentally as it is a standard first-line treatment in CML. Assessment of vesicles transfer, metabolic parameters, mitochondrial function phenotyping, Trans-SILAC proteomics and metabolomics, together with apoptosis assessment, verified the influence of stroma on metabolic plasticity, protein transfer and adaptation to imatinib in leukemic cells. Trans-system evaluated necessity of direct cell-cell contact. Data from single-cell atlas of diagnostic CML bone marrow were used to correlate gene expression profiles with clinical outcome. Telaglenastat was used to validate the clinical potential of our findings. Stromal cells enhanced metabolic plasticity and oxidative capacity in leukemia, thereby protecting against metabolic decline and oxidative stress caused by imatinib. Direct stroma-leukemia contact was necessary for vesicles transfer, metabolic rearrangement and protection from imatinib-induced apoptosis. This was accompanied with shift towards OXPHOS activity, associated with increased utilization of non-glucose substrates. We found the presence of stromal TCA-related proteins in leukemic cells, associated with higher TCA cycle dynamics and activity, increased glutamine and reduced oxidative stress. The gene expression profiles correlated with clinical resistance to TKIs. Targeting the glutamine-TCA axis by telaglenastat in combination with imatinib reversed the stroma-driven protection, leading to increased apoptosis. This study describes a novel mechanism of direct bone marrow-mediated protection of leukemic cells from imatinib/TKI, related to transfer of metabolic proteins leading to higher activity of TCA cycle, metabolic plasticity and adaptation. Targeting the stroma-driven TCA cycle-related metabolism combined with imatinib presents a promising strategy to achieve therapeutic efficacy to overcome bone marrow microenvironment-mediated protection in CML.

Prostaglandin F2α receptor (FP receptor) signaling is a plausible target for promoting hair growth, but clinical data on topical latanoprost acid (the active free-acid FP agonist) in hair loss are lacking. This study aimed to evaluate the clinical efficacy, safety, and mechanistic basis of topical latanoprost acid in women with female androgenetic alopecia. In this investigator-initiated, randomized, double-blind, single-center, dose-ranging pilot trial, 29 adult women with hair loss predominantly consistent with female androgenetic alopecia were randomized to vehicle (n = 2) or topical latanoprost acid 0.01

Duchenne muscular dystrophy (DMD) is characterized by progressive muscle degeneration and neuropsychiatric abnormalities. Loss of full-length dystrophins is both necessary and sufficient to initiate DMD. These isoforms are expressed in the hippocampus, cerebral cortex (Dp427c), and cerebellar Purkinje cells (Dp427p). However, our understanding of the consequences of their absence, which is crucial for developing targeted interventions, remains inadequate. We combined RNA sequencing with genome-scale metabolic modelling (GSMM), immunodetection, and mitochondrial assays to investigate dystrophic alterations in the brains of the mdx mouse model of DMD. The cerebra and cerebella were analysed separately to discern the roles of Dp427c and Dp427p, respectively. Investigating these regions at 10 days (10d) and 10 weeks (10w) followed the evolution of abnormalities from development to early adulthood. These time points also encompass periods before onset and during muscle inflammation, enabling assessment of the potential damage caused by inflammatory mediators crossing the dystrophic blood–brain barrier. For the first time, we demonstrated that transcriptomic and functional dystrophic alterations are unique to the cerebra and cerebella and vary substantially between 10d and 10w. The common anomalies involved altered numbers of retained introns and spliced exons across mdx transcripts, corresponding with alterations in the mRNA processing pathways. Abnormalities in the cerebra were significantly more pronounced in younger mice. The top enriched pathways included those related to metabolism, mRNA processing, and neuronal development. GSMM indicated dysregulation of glucose metabolism, which corresponded with GLUT1 protein downregulation. The cerebellar dystrophic transcriptome, while significantly altered, showed an opposite trajectory to that of the cerebra, with few changes identified at 10 days. These late defects are specific and indicate an impact on the functional maturation of the cerebella that occurs postnatally. Although no classical neuroinflammation markers or microglial activation were detected at 10 weeks, specific differences indicate that inflammation impacts DMD brains. Importantly, some dystrophic alterations occur late and may therefore be amenable to therapeutic intervention, offering potential avenues for mitigating DMD-related neuropsychiatric defects.

During the September 2024 Science Festival in Warsaw, three unique events were organized in collaboration between the Nencki Institute of Experimental Biology PAS, the Academy of Fine Arts in Warsaw, and the Marceli Nencki Foundation for the Advancement of Biological Sciences. These events focused on exploring interactions between biological sciences and visual arts. As part of this collaboration, an exhibition titled “Vibration” was presented at the Hermitage in the Royal Łazienki Park. Additionally, lectures and an exhibition titled “Can Molecular Biology Inspire Visual Artists” were held at the Nencki Institute PAS. A unique event, the “Bio-Workshop”, was organized for high school students at the Graphic Arts Department of the Academy of Fine Arts in Warsaw. In addition to recounting and detailing these events, this article presents a broader context of the interplay between art and natural sciences. The benefits of creative interdisciplinary activities are discussed, highlighting the potential for mutual inspiration between these two fields, benefiting both artists and scientists.

Leukemia cells residing in the bone marrow often exhibit resistance to tyrosine kinase inhibitors. Metabolic rearrangement of cancer cells has recently gained particular attention as a possible cause of adaptation and insensitivity to drug treatment. We demonstrated here that stromal cells directly transferred the membrane vesicles together with proteins related to the tricarboxylic acid (TCA/Krebs) cycle to leukemic cells. This transfer was dependent on direct cell-to-cell contact and led to increased metabolic plasticity. In addition, co-culture increased activities of the TCA cycle, oxidative phosphorylation and oxidative capacity, therefore protected from loss of metabolic homeostasis and increased oxidative stress in response to imatinib. As a result of co-culture with stroma, the reductions in OXPHOS, mitochondria-related parameters and the maximal respiration observed in imatinib-treated leukemic cells, were substantially less present, and the spare respiratory capacity parameter was even higher compared to control cells. Metabolome profiling revealed that co-cultured leukemic cells treated with imatinib exhibit higher levels of TCA-related metabolites such as isocitric acid, L-malic acid ketoglutaric acid and cis-aconitic acid, as well as lower level of oxidative stress. The co-culture with rho0 stromal cells and analysis of horizontal transfer of GFP-positive mitochondria excluded transfer of mitochondria and their oxidative phosphorylation status as important for the stroma-driven metabolic protection. Altogether, our data provide insight into the novel mechanism of the bone marrow-mediated protection of leukemic cells, associated with metabolic adaptation to imatinib treatment. Metabolic plasticity as a resistance driver has been indicated in leukemia stem cells, however our data indicate that the presence of stromal cells may provide such support to all leukemic cells. In conclusion, we postulate that elements involved in the TCA-related metabolic plasticity in leukemia can be targeted to achieve a therapeutic effect and to overcome the resistance caused by the bone marrow microenvironment.

Calcification of dystrophic skeletal muscles was described previously and attributed, among others, to ER-stress, elevated phosphate concentration and chronic inflammation. Tauroursodeoxycholic acid (TUDCA) is considered an artificial chaperone protecting cells against ER-stress thus could prevent an ectopic mineralisation of soft tissues. Because an enhanced ER-stress is a feature of dystrophic muscles and it promotes soft tissue mineralisation we hypothesised that TUDCA treatment should reduce mineral deposits in dystrophic skeletal muscles, and tested this concept using two mouse models of DMD. Four-week old mdx, mdxβetageo and w/t mice were administered TUDCA in drinking water for 4 weeks. At 8 weeks, following tissue-clearing and calcium minerals staining with alizarin, mineralisation was evaluated using whole body scanning. Additionally, isolated skeletal muscles were analysed by Western blotting for ER-stress and calcification markers, and using various microscopic methods. Enzymatic activity of alkaline phosphatase was also assayed. Unexpectedly, TUDCA enhanced calcification of dystrophic but not dystrophin-positive muscles. TUDCA did not affect the elevated ER-stress markers found in dystrophic muscles nor impact pro-calcifying proteins RUNX2, Osterix and BMP2/4, which were also overexpressed in dystrophic muscles. The alkaline phosphatase levels, which were reduced in dystrophic muscles, were not affected by this treatment. The increase in ectopic calcification in dystrophic muscles induced by TUDCA is specific to muscles lacking dystrophin. This effect is not linked to the alleviation of ER stress or the overexpression of proteins directly involved in calcium mineral accumulation.

Energy metabolism homeostasis emerges as a dominant element influencing mesenchymal stem/stromal cells' trajectory of development. The predominant glycolysis activity is a primary driver of cell proliferation and maintenance of the high-energetic state. Here, we examined the functions of two crucial auxiliary pathways: the phosphate-pentose pathway (PPP) and fructose-2,6-biphosphate pathway (FBP) to evaluate their impact on the therapeutic potential of Adipose-Derived Stem/Stromal cells (ASCs) during prolonged culture in various oxygen conditions: 5 % O2 - physiological normoxia or 21 % O2 - atmospheric oxygen. Our findings demonstrate that ASCs cultured in 5 % O2 increased the rate of proliferation, migration, and expression of stemness factors, which is prominent during the initial and middle passages. Additionally, ASCs cultured in a 5 % O2 exhibited heightened protection mechanisms against free radicals, increased LDH gene expression, and elevated extracellular acidification rate (ECAR). By estimating the HIF-1α level, we concluded that 5 % oxygen conditions were insufficient to induce a profound hypoxic state in ASCs. However, at the protein level, both the PPP and FBP pathways appeared to be more active in young (2-passage) cells, regardless of oxygen conditions, and their activity diminished over time. Additionally, the chemical suppression of G6PDH by Polydatin and inhibition of PFKFB3 by PFK-158 in ASCs (passage-2) revealed dose- and time-dependent effect on decreasing migratory capabilities of cells. Nevertheless, our work underscores the adaptable nature of ASC metabolism to prevailing external conditions, with the aging of the culture contributing to the decline in glycolysis-associated auxiliary pathways.

Mitochondria are essential for the regulation of the metabolic state of skeletal muscle, making their structure and function crucial for muscle performance. Myosin VI (MVI), an unconventional minus-end-directed motor, is expressed in skeletal muscle and myogenic cells. To explore its role in mitochondrial function and muscle metabolism, we used MVI knockout mice (Snell's waltzer, SV MVI-KO) and their heterozygous littermates. We analyzed muscle samples from newborn (P0) and adult mice (3- and 12-mo-old) and found that both MVI mRNA and protein levels were highest in newborn muscles and decreased with age. MVI expression also varied by muscle type, being highest in the slow-twitch soleus muscle (SOL) of adult mice. Loss of MVI had the most significant effects on SOL, which contains the highest number of mitochondria compared with fast-twitch muscles. MVI loss resulted in reduced respiratory capacity and adenosine-5'-triphosphate production in myogenic cells, indicating impaired mitochondrial function. Furthermore, MVI deficiency caused a shift from glycolytic to oxidative fiber types, especially in SOL. We also observed increased phospho-AMP-activated protein kinase levels in MVI-KO SOL across all time points, along with downregulation of the mammalian target of rapamycin pathway and upregulation of proteins involved in lipolysis. These findings highlight MVI as a novel regulator of metabolic processes in skeletal muscle.NEW & NOTEWORTHY Myosin VI (MVI), a motor protein, regulates mitochondrial function and metabolism in skeletal muscle. In MVI-knockout mice, its expression peaked in neonatal muscles and remained highest in adult soleus. MVI loss impaired mitochondrial respiration, reduced ATP production, and promoted a shift toward oxidative fibers. It also increased AMPK, suppressed mTOR signaling, and altered lipid metabolism, including reduced triacylglycerol levels. These findings reveal MVI's important role in energy balance, protein synthesis, and lipid regulation in muscle.

Background:OATD-01 is a chitinase-1 (CHIT1) inhibitor, reducing inflammation and fibrosis in animal models where chronic inflammation leads to tissue remodeling. CHIT1, predominantly secreted by macrophages, is overexpressed in metabolic dysfunction-associated steatohepatitis (MASH). Methods and results:In the study, we demonstrated the therapeutic efficacy of OATD-01 in two murine models (STAM, DIAMOND) and one rat model (CDHFD) of MASH. RNA-Seq analysis of livers obtained from CDHFD rat model revealed that OATD-01 reversed MASH-dysregulated genes. In addition to reducing inflammation and fibrosis observed in the rat model, RNA-Seq demonstrated that OATD-01 regulated key metabolic processes such as acetyl-CoA metabolism, triglyceride metabolism, cholesterol synthesis, cholesterol flux, and glycolysis. Using functional assay performed on bone marrow-derived macrophages (BMDMs) we demonstrated that both genetic and pharmacological inactivation of CHIT1 resulted in inhibition of glucose uptake. As a consequence, our data suggest decreased glycolysis, accompanied by increased ATP levels, lower citrate, and increased acetate levels, ultimately leading to a reduced IL-1β secretion in BMDMs. Conclusions:These results revealed the key role for CHIT1 in regulating metabolism. OATD-01 is a macrophage modulator that can directly restore metabolic balance and consequently inhibit inflammation and fibrosis, supporting its use for MASH treatment.

Ubiquitin-specific proteases (USPs) are the main members of deubiquitinases (DUBs) that catalyze removing ubiquitin chains from target proteins, thereby modulating their half-life and function. Enzymatic activity of USP21 regulates protein degradation which is critical for maintaining cell homeostasis. USP21 determines the stability of oncogenic proteins and therefore is implicated in carcinogenesis. In this study, we investigated the effect of USP21 deletion on cancer cell metabolism. Transcriptomic and proteomic analysis of USP21 KO HAP-1 cells revealed that endogenous USP21 is critical for the expression of genes and proteins involved in mitochondrial function. Additionally, we have found that the deletion of USP21 reduced STAT3 activation and STAT3-dependent gene and protein expression in cancer cells. Genetic deletion of USP21 impaired mitochondrial respiration and disturbed ATP production. This resulted in cellular consequences such as inhibition of cell proliferation and migration. Presented results provide new insights into the biology of USP21, suggesting novel mechanisms for controlling STAT3 activity and mitochondrial function in tumor cells. Taken together, our findings indicate that targeting USP21 dysregulates the energy status of cancer cells offering new perspectives for anticancer therapy.

AbstractThere is increasing evidence of mitochondrial dysfunction in autism spectrum disorders (ASD), but the causal relationships are unclear. In an ASD patient whose identical twin was unaffected, we identified a postzygotic mosaic mutation p.Q639* in the TRAP1 gene, which encodes a mitochondrial chaperone of the HSP90 family. Additional screening of 176 unrelated ASD probands revealed an identical TRAP1 variant in a male patient who had inherited it from a healthy mother. Notably, newly generated knock-in Trap1 p.Q641* mice display ASD-related behavioral abnormalities that are more pronounced in males than in females. Accordingly, Trap1 p.Q641* mutation also resulted in sex-specific changes in synaptic plasticity, the number of presynaptic mitochondria, and mitochondrial respiration. Thus, the TRAP1 p.Q639* mutation is the first example of a monogenic ASD caused by impaired mitochondrial protein homeostasis.

Background: The tobacco use is one of the biggest public health threats worldwide. Cigarette smoke contains over 7000 chemicals among other aldehydes, regarded as priority toxicants. beta-escin (a mixture of triterpenoid saponins extracted from the Aesculus hippocastanum. L) is a potent activator of aldehyde dehydrogenase (ALDH) - an enzyme catalyzing oxidation of aldehydes to non-toxic carboxylic acids. Purpose: The aim of this study was to evaluate the effect of beta-escin on ALDH activity, ALDH isoforms mRNA expression and cytotoxicity in nasal epithelial cells exposed to cigarette smoke extract (CSE). Methods: Nasal epithelial cells from healthy non-smokers were treated with beta-escin (1 mu M) and exposed to 5% CSE. After 6- or 24-hours of stimulation cell viability, DNA damage, ALDH activity and mRNA expression of ALDH isoforms were examined. Results: 24 h beta-escin stimulation revised CSE induced cytotoxicity and DNA damage. Cells cultured with beta-escin or exposed to CSE responded with strong increase in ALDH activity. This effect was more pronounced in cultures treated with combination of beta-escin and CSE. The strongest stimulatory effect on ALDH isoform mRNA expression was observed in cells cultured simultaneously with beta-escin and CSE: at 6 h for ALDH1A1 and ALDH3A1, and at 24 h for ALDH1A3, ALDH3A2, ALDH3B1, and ALDH18A1. Combined beta-escin and CSE treatment prevented the CSE-induced inhibition of ALDH2 expression at 24 h. Conclusions: beta-escin is an effective ALDH stimulatory and cytoprotective agent and might be useful in the prevention or supportive treatment of tobacco smoke-related diseases.

Introduction: One of the key factors that may influence the therapeutic potential of mesenchymal stem/stromal cells (MSCs) is their metabolism. The switch between mitochondrial respiration and glycolysis can be affected by many factors, including the oxygen concentration and the spatial form of culture. This study compared the metabolic features of adipose-derived mesenchymal stem/stromal cells (ASCs) and dedifferentiated fat cells (DFATs) cultivated as monolayer or spheroid culture under 5% O-2 concentration (physiological normoxia) and their impact on MSCs therapeutic abilities. Results: We observed that the cells cultured as spheroids had a slightly lower viability and a reduced proliferation rate but a higher expression of the stemness-related transcriptional factors compared to the cells cultured in monolayer. The three-dimensional culture form increased mtDNA content, oxygen consumption rate (OCR) and extracellular acidification rate (ECAR), especially in DFATs-3D population. The DFATs spheroids also demonstrated increased levels of Complex V proteins and higher rates of ATP production. Moreover, increased reactive oxygen species and lower intracellular lactic acid levels were also found in 3D culture. Conclusion: Our results may suggest that metabolic reconfiguration accompanies the transition from 2D to 3D culture and the processes of both mitochondrial respiration and glycolysis become more active. Intensified metabolism might be associated with the increased demand for energy, which is needed to maintain the expression of pluripotency genes and stemness state.

This study aimed to investigate the putative role of nicotinamide N-methyltransferase in the metabolic response of human aortic endothelial cells. This enzyme catalyses S-adenosylmethionine-mediated methylation of nicotinamide to methylnicotinamide. This reaction is accompanied by the reduction of the intracellular nicotinamide and S-adenosylmethionine content. This may affect NAD+ synthesis and various processes of methylation, including epigenetic modifications of chromatin. Particularly high activity of nicotinamide N-methyltransferase is detected in liver, many neoplasms as well as in various cells in stressful conditions. The elevated nicotinamide N-methyltransferase content was also found in endothelial cells treated with statins. Although the exogenous methylnicotinamide has been postulated to induce a vasodilatory response, the specific metabolic role of nicotinamide N-methyltransferase in vascular endothelium is still unclear. Treatment of endothelial cells with bacterial lipopolysaccharide evokes several metabolic and functional consequences which built a multifaceted physiological response of endothelium to bacterial infection. Among the spectrum of biochemical changes substantially elevated protein level of nicotinamide N-methyltransferase was particularly intriguing. Here it has been shown that silencing of the nicotinamide N-methyltransferase gene influences several changes which are observed in cells treated with lipopolysaccharide. They include altered energy metabolism and rearrangement of the mitochondrial network. A complete explanation of the mechanisms behind the protective consequences of the nicotinamide N-methyltransferase deficiency in cells treated with lipopolysaccharide needs further investigation.

EDITORIAL article Front. Cardiovasc. Med., 23 September 2022Sec. Cardiovascular Metabolism https://doi.org/10.3389/fcvm.2022.1024917

•Autophagy and endothelial function.•Crosstalk between autophagy and inflammasome.•Endothelial mitochondria in inflammation.•Mitochondrial quality control in endothelium.

Treatment of endothelial cells with bacterial lipopolysaccharide (LPS) evokes a number of metabolic and functional consequences which built a multifaceted physiological response of endothelium to bacterial infection. Here effects of LPS on human aortic endothelial cells (HAEC) have been investigated. Among the spectrum of biochemical changes substantially elevated N-nicotinamide methyltransferase (NNMT) protein level was particularly intriguing. This important enzyme may potentially affect cellular metabolism by two means: direct regulation of methylnicotinamide level and availability of nicotinamide, that at least potentially may influence NAD + synthesis, and regulation of S-adenosylmethionine concentration and therefore controlling methylation of many proteins including chromatin. This may have epigenetic consequences. This paper is focused on NNMT, despite the fact that in the presence of LPS additional effects of this compound mask pure (canonical) consequences of the elevated NNMT protein which are an increased MNA synthesis or reduced NAD + level. On the other hand, however, it has been shown that silencing of the NNMT-encoding gene prevents several changes which are observed in control HAECs treated with LPS. They include significantly increased calcium response to thapsigargin (store-operated calcium entry), altered energy metabolism which is switched to anaerobic glycolysis and rearrangement of the mitochondrial network. However, a biochemical mechanism behind the protective consequences of the NNMT deficiency in cells treated with LPS remains unexplained.