Jarosław Czyż

Background: Cardiac fibrosis drives adverse myocardial remodelling through persistent fibroblast activation, ECM deposition, and impaired cardiac function. Current therapies offer limited protection against cardiac fibrosis progression. Elafibranor is a dual PPAR-α/δ agonist approved for the treatment of liver disease. However, its effects in human models of cardiac fibrosis remain insufficiently explored. Methods: Elafibranor was evaluated in complementary human in vitro TGF-β ₁ -induced cardiac fibrosis models: 2D primary fibroblasts, 3D fibroblast spheroids, spontaneously contracting 3D cardiac microtissues, and hiPSC-derived cardiomyocytes. Viability, apoptosis, fibroblast activation, ECM remodelling, mitochondrial respiration, nucleotide and NAD pools, calcium handling, contractility, and transcriptomic profiles were assessed. Results: At non-cytotoxic concentrations, elafibranor attenuated TGF-β ₁ -driven cardiac fibrosis responses. In 2D cardiac fibroblasts, it reduced myofibroblast differentiation, procollagen 1α1 secretion, and partially restored mitochondrial respiratory capacity. In 3D spheroids, it preserved viability, attenuated caspase-3/7 activation, and suppressed procollagen 1α1 release. In cardiac microtissues, elafibranor reduced ECM accumulation, shifted transcriptomic profiles toward redox-metabolic/cytoprotective pathways, altered adenine nucleotide and NAD pools, and partially recovered contraction parameters. In hiPSC-derived cardiomyocytes, elafibranor modulated calcium handling, contractility, and mitochondrial respiration. Conclusions: Elafibranor mitigates TGF-β ₁ -driven cardiac fibrosis by suppressing fibroblast activation and ECM remodelling while promoting adaptive metabolic, redox, and bioenergetic responses, supporting balanced PPAR-α/δ activation as a potential therapeutic strategy for cardiac fibrosis. Graphical

Chemotherapy-induced metabolic reprogramming of glioblastoma multiforme (GBM) cells increases intracellular levels of reductive and energetic carriers, thereby fueling drug-relocation and retention systems and enhancing GBM drug-resistance. We have previously shown the role of this process in the adaptation of poly(morpho)nuclear “giant” cells (PGCs) in T98G populations to doxorubicin (DOX)-induced stress. Here, we addressed the role of a “resistance triad”, which coordinates metabolic T98G reprogramming with the activation of the drug-relocation and drug-retention axis, in the recovery of GBM populations from chemotherapeutic stress. A combination of proteomic analyses with metabolic and phenotypic profiling of pulse DOX-treated T98G cells revealed the significance of mitochondrial dynamics for the efficiency of the T98G “resistance triad”. DOX-induced mobilization of ATP-generating systems and ATP-dependent anabolic pathways was accompanied by the formation of DOX-negative, “mosaic” mitochondrial networks and the upregulation of mitofusin-2 (MFN2) in T98G PGCs. Transient MFN2 down-regulation correlated with the respiratory capacity of T98G cells, while impairing cell welfare in the absence and presence of DOX. However, minute fractions of PGCs, which withstood combined MFN2 down-regulation and pulse DOX treatment, retained mitochondrial networks and displayed efficient ABC transporter-/V-type channel-dependent lysosomal DOX retention. Collectively, a “triad” of mitochondrial activation, ABC transporter-dependent perinuclear redistribution and V-type channel-mediated lysosomal DOX compartmentalization determines DOX resistance of T98G cells. Whereas MFN2-dependent mitochondrial rearrangements may contribute to these processes, complementary adaptative mechanisms can compensate MFN2 dysfunction, limiting its potential as a therapeutic target.

Receptor‐interacting protein kinase 4 (RIPK4) has been implicated in the progression of numerous tumours. In nonmelanoma skin cancer, RIPK4 plays a suppressor role, whereas in melanoma, it functions as an oncogene that modulates key signalling pathways involved in melanoma cell survival and expansion. Increased RIPK4 levels in metastatic melanoma biopsies prompted us to investigate the consequences of RIPK4 loss for the invasive and metastatic phenotype of melanoma cells. Using an integrated approach involving clinical samples, in vivo xenograft models, transcriptomic analysis and 3D functional assays, we show that RIPK4 deletion significantly reduces pulmonary metastasis formation. This reflects its role in late‐stage metastatic events, such as extravasation and colonization, particularly since this phenotype correlates with extensive transcriptional reprogramming of adhesion‐ and motility‐related genes in melanoma cells, as evidenced by next‐generation sequencing and functional validation in spheroid and collagen‐based models. Despite exhibiting features of a partial shift towards an amoeboid phenotype such as membrane blebbing and increased MLC2 phosphorylation, RIPK4 knockout cells display impaired motility and invasion. Re‐expression of RIPK4 restores mesenchymal morphology and migratory capacity. Together, our results establish RIPK4 as a critical regulator of melanoma invasion and metastasis. Nonetheless, they also demonstrate that the loss of RIPK4 function activates compensatory phenotypic shifts in melanoma cells that fail to fully rescue their invasive potential.

Early prevention of pathological changes underlying gastric cancer (GC) development is a critical strategy, offering the most effective opportunity to limit malignant progression and improve patient outcomes. We have previously demonstrated that Helicobacter pylori (Hp) (cagA⁺vacA⁺) contributes to GC development by activating gastric fibroblasts toward CAF-like phenotype, eliciting aggressive, cancer stem cells (CSCs)-related malignant transformation of LGR5⁺ normal epithelial cells. A key mediator of these processes appears to be the NF-κB/STAT3 axis. Therefore, our aim was to investigate the protective role of hydrogen sulfide (H₂S) as a potential novel strategy for counteracting Hp-induced fibroblast reprogramming. Human fibroblasts were infected with Hp (cagA+vacA+) for 120 h. The fast-releasing H₂S donor NaHS (50, 100, 200 and 400 µM) was added every 24 h. Activation markers, corresponding signaling pathways, H₂S release and activities of H₂S-metabolizing enzymes were determined. NaHS reduced Hp-induced fibroblast activation and their pro-inflammatory, pro-tumorigenic markers, which was associated with the inhibition of NF-κB/STAT3 axis and Twist expression. Additionally, it modulated sulfur metabolism while preserving sulfur-enzyme homeostasis. NaHS limited Hp adhesion (high doses), reduced reinfection-induced activation and increased sensitivity of Hp to metronidazole. These findings suggest that H₂S signaling may represent a modulatory factor of NF-κB/STAT3-driven inflammatory responses during Hp infection and warrant further investigation.

Background: The combination of manganese porphyrins (MnPs) and ascorbate (ASC) represents a promising redox-based therapeutic approach for selectively targeting cancer cells. We investigated the cytotoxic effects of two structurally distinct MnPs (MnTPPS and MnF₂BMet) with differing lipophilicity and potential membrane permeability in combination with ASC. Methods: Cancer cell lines (MCF-7, PANC-1, U87, T98G, AT-2) and normal human dermal fibroblasts (HDFs) were treated with MnTPPS and MnF₂BMet in the absence or presence of ASC. Viability, migration potential, and intracellular oxidative stress were assessed using single-cell methods. Results: MnPs alone exhibited no intrinsic cytostatic or cytotoxic activity, as confirmed by proliferation, viability, and motility assays. When combined with ASC, both MnTPPS and MnF₂BMet significantly enhanced ASC-induced oxidative stress, leading to lipid peroxidation, glutathione depletion, mitochondrial dysfunction, and cell membrane disruption. Time-lapse microscopy revealed rapid necrotic cell death under co-treatment. Catalase fully abolished cytotoxicity, indicating the essential role of hydrogen peroxide. In contrast, dehydroascorbate (DHA), which increases intracellular ASC levels, did not induce the same toxicity, suggesting that extracellular ROS generation contributes predominantly to the observed effects. Normal fibroblasts were minimally affected, supporting the MnPs–ASC system’s selectivity toward cancer cells. Conclusions: MnTPPS and MnF₂BMet enhance extracellular oxidation of ascorbate and subsequent ROS production, leading to selective oxidative-stress-mediated cancer cell death. This study supports the potential of MnPs–ASC redox catalysis as a complementary oxidative-stress-based anticancer strategy and highlights the need for further mechanistic and structure–activity investigations.

The aim of the Special Issue "Acta Biochimica Polonica Reviews | 2023-2024" published in Acta Biochimica Polonica was to gather review articles from various research areas, focusing on cellular and molecular biology, and biomedicine. This editorial paper provides a concise overview of four publications published within the frames of this Special Issue.Plant transcriptomes are highly complex entities shaped by a multitude of stressors in a spatiotemporally heterogeneous manner (Imadi et al., 2015). Numerous abiotic stressors represent part of the normal ecological niche to which plants are adapted, often triggering constitutive or primed stress-response programs. Two papers published in the Special Issue, the first (Rurek, 2025) and the third (Rurek and Smolibowski, 2024), provide a deepened meta-analysis of differences in plant transcriptomes under the impact of various stressors and across diverse vegetative and generative organs and tissues. Data were taken from numerous model, crop and medicinal plant species, and from various transcriptomic platforms, including single cell and spatial RNA-seq (Peirats-Llobet et al., 2023;Wang et al., 2024;Guo et al., 2025).The enriched gene ontology terms from affected gene families and the respective transcription factors were compared. The supplementary data in both papers provide summary of quantitative alterations in gene expression patterns and details on experimental conditions. In their review, Rurek and Smolibowski (2024) compared dynamic transcriptomic responses to selected abiotic and biotic stressors (Wang et al., 2020). Stress responses involved both species/stressor-specific but also shared gene families (coding mostly photosynthetic proteins and secondary metabolism enzymes).In turn, Rurek (2025) aimed to characterize the most relevant spatiotemporal transcriptomic responses in selected vegetative and generative plant organs and tissues in the developmental context (Huang et al., 2016). The dynamicity of organ/tissue-specific responses was also compared in the context of the complexity and diversity of recently characterized plant genomes and transcriptomes. The specificity of organ/tissue-specific transcriptomes related to the over-representation of certain gene families and transcription factors was also emphasized. In addition, the perspectives for the application of medicinal plant species in industrial synthesis of valuable secondary metabolites were outlined based on organ-specific transcriptomic responses (Guo et al., 2021).From the reviews by Rurek and Smolibowski (2024) and Rurek (2025), the relevance of current plant transcriptomic studies both for basic research as well as for agriculture can be visioned. Functional analyzes would allow for better characterization of stress-responsive genes and less-known stress acclimatory mechanisms. On this basis, more stress-resistant crop cultivars could be designed in the future, based on advanced tools of plant biotechnology (Sriboon et al., 2010;Liu et al., 2024). Such actions should also benefit more from plant metabolome heterogeneity. More consistent usage of the potential of medicinal species in the synthesis of pharmaceutically important compounds may help to combat a range of lifestyle-related diseases.Modulation of the gut microbiome is another promising option to deal with the fatal increase in lifestyle-related diseases. The second paper in the Special Issue (Gofron et al., 2024) provides the meta-analysis of the complex effects of Akkermansia muciniphila (A. municiphila) on human health and their therapeutic applications. This facultatively anaerobic, gram-negative microbial species, initially isolated in 2004, colonizes the mucosa of the colon and rectum crypts and specializes in mucin degradation. Intensity of crypt colonisation by A. muciniphila correlates with the increased likelihood of colorectal cancer (Derrien et al., 2010;Nath and Mukherjee, 2014). However, available data also indicate the participation of A. municiphila in cobalamin biogenesis and in the maintenance of intestinal and cardiovascular health; these bacteria hamper endothelium inflammation and atherosclerosis (Shin et al., 2014;Li et al., 2016;Mok et al., 2020). By various cellular and molecular mechanisms, they control body weight and cardiovascular disorders, including atrial fibrillation, and can be used in obesity therapy (Dao et al., 2016;Depommier et al., 2019;Luo et al., 2022). A. municiphila also participates in the biogenesis of the intestinal mucosa layer and in the host protection against several inflammatory diseases (Qu et al., 2021).However, because of the limited number of reports, the interconnections between these activities and their general effects on human welfare need further exploration. In addition, the safety and potential of consuming living cultures of A. municiphila to maintain their positive cardiovascular effects, as well as more specialized studies on the impact of A. municiphila on the circulatory system should be investigated.For a long time, mitochondria were mainly regarded as the centers of bioenergetical processes and cellular metabolism. Novel aspects of mitochondria function include their participation in cytoprotection, cellular senescence, tumorigenesis, fibrosis and inflammatory responses (Li et al., 2020;Barrera et al., 2021;Chapa-Dubocq et al., 2023;Szabo and Szewczyk, 2023). The fourth publication of this Issue, a mini-review by Szewczyk ( 2024), focuses on recent findings concerning the role of mitochondrial K-dependent (mitoK) channels in the regulation of mitochondrial and cellular physiology. The discovery of mitoK channels in 1991 (Inoue et al., 1991), although initially underestimated, led to their recognition as crucial players in multiple aspects of mitochondrial biogenesis across various taxa (Koszela-Piotrowska et al., 2009;Laskowski et al., 2015;Szabo and Szewczyk, 2023). In this paper, the research of multiple mitochondrial K-dependent...

Background: The combination of manganese porphyrins (MnPs) and ascorbate (ASC) represents a promising redox-based therapeutic approach for selectively targeting cancer cells. In this study, we investigated the cytotoxic effects of two structurally distinct MnPs (MnTPPS and MnF₂BMet) with differing lipophilicity and potential membrane permeability in combination with ASC. Methods: Human cancer cell lines (MCF-7, PANC-1, U87, T98G, AT-2), and normal human dermal fibroblasts (HDF), were treated with MnTPPS and MnF₂BMet in the absence or presence of ASC. Their viability and invasive potential were then assessed with single-cell methods along with the analyses of intracellular oxidative stress. Results: MnPs alone exhibited no intrinsic cytostatic or cytotoxic activity, as confirmed by proliferation, viability, and motility assays. When combined with ASC, both MnTPPS and MnF₂BMet significantly enhanced ASC-induced oxidative stress, leading to lipid peroxidation, glutathione depletion, mitochondrial dysfunction, and cell membrane disruption. Time-lapse microscopy revealed rapid necrotic cell death under co-treatment. The cytotoxic effect was completely abolished by catalase, indicating the essential role of hydrogen peroxide. In contrast, dehydroascorbate (DHA), which increases intracellular ASC levels, did not reproduce the same toxicity, suggesting that extracellular ROS gener ation contributes predominantly to the observed effects. Normal fibroblasts were minimally affected, supporting the selectivity of the MnPs–ASC system toward cancer cells. Conclusions: The results indicate that MnTPPS and MnF₂BMet enhance extracellular oxidation of ascorbate and subsequent ROS production, leading to selective oxidative stressmediated cancer cell death. This study supports the potential of MnPs–ASC redox catalysis as a complementary oxidative stress–based anticancer strategy and highlights the need for further mechanistic and structure–activity investigations.

Skin infiltration by neutrophils is a hallmark of the chronic inflammatory skin disease psoriasis, yet the mechanisms underlying neutrophil recruitment and positioning in chronically inflamed skin remain poorly understood. In this study, we demonstrate the significant impact of a total genetic deficiency of secretory leukocyte protease inhibitor (SLPI) on neutrophil migration in mouse skin. Without SLPI, neutrophils displayed an unconventional migratory pattern, characterized by altered interactions with vessel walls and reduced efficiency in extravasating from blood vessels into skin tissue during the early stages of experimental psoriasis. This was associated with changes in tissue motility, positioning neutrophils farther from the skin entry vessels and closer to the skin surface. Neutrophil diapedesis was partially dependent on SLPI within the neutrophils themselves. The impact of SLPI on neutrophil movement was further supported by the increased migration of human neutrophils in the presence of neutrophil-penetrant recombinant SLPI. Additionally, our data suggest that neutrophils with varying capacities for vessel wall interaction are released from the bone marrow into circulation in an SLPI-dependent manner. These findings establish a role for SLPI in regulating the spatiotemporal infiltration of neutrophils into the skin in psoriasis, highlighting its relevance to psoriasis pathophysiology.

Vascular endothelial growth factor‐A (VEGF‐A) plays a pivotal role in inflammatory rheumatic diseases, including spondyloarthritis (SpA). Recently, we have demonstrated that the expression of VEGF‐A in human classical monocytes is positively associated with the number of swollen and painful joints in SpA patients. Therefore, we tested whether the anti‐VEGF‐A therapy can affect the hallmarks of SpA in the SKG mouse model. When initiated at the disease onset, the administration of anti‐VEGF‐A monoclonal antibodies (mAbs) significantly reduced the objective symptoms of SpA in the curdlan suspension‐treated mice compared to their untreated and isotypic control‐treated counterparts. Micro‐computed tomography (CT) imaging revealed substantial benefits of the treatment, with anti‐VEGF‐A mAbs‐treated mice exhibiting preserved joint spaces, reduced number and depth of bone erosions, and limited new bone formation in hind paws, calcaneus, sacroiliac joints, and caudal vertebrae. These effects remained in contrast to the pronounced damage and osteogenesis in relevant skeletal regions of control animals. The histological assessment confirmed reduced synovial inflammation and bone erosions in anti‐VEGF‐A mAbs‐treated mice, underscoring the efficacy of the treatment in mitigating SpA bone damage. Collectively, anti‐VEGF‐A mAbs treatment favors the maintenance of joint and spine structures, alleviates bone destruction and osteogenesis, and reduces local inflammation in the mouse SpA model. Our study pinpoints anti‐VEGF‐A mAb therapy as a promising avenue to understand the SpA pathogenesis and as a treatment option. It also addresses vascular and inflammatory aspects of the disease and illustrates the potential of the SKG mouse SpA model for assessing the long‐term safety of anti‐VEGF‐A therapy before its clinical translation.

Background: Multi-drug resistance of poly(morpho)nuclear giant cells (PGCs) determines their cytoprotective and generative potential in cancer ecosystems. However, mechanisms underlying the involvement of PGCs in glioblastoma multiforme (GBM) adaptation to chemotherapeutic regimes remain largely obscure. In particular, metabolic reprogramming of PGCs has not yet been considered in terms of GBM recovery from doxorubicin (DOX)-induced stress. Methods: Long-term proteomic and metabolic cell profiling was applied to trace the phenotypic dynamics of GBM populations subjected to pulse DOX treatment in vitro, with a particular focus on PGC formation and its metabolic background. The links between metabolic reprogramming, drug resistance and drug retention capacity of PGCs were assessed, along with their significance for GBM recovery from DOX-induced stress. Results: Pulse DOX treatment triggered the transient formation of PGCs, followed by the appearance of small expanding cell (SEC) clusters. Development of PGCs was accompanied by the mobilization of their metabolic proteome, transient induction of oxidative phosphorylation (OXPHOS), and differential intracellular accumulation of NADH, NADPH, and ATP. The metabolic background of PGC formation was confirmed by the attenuation of GBM recovery from DOX-induced stress following the chemical inhibition of GSK-3β, OXPHOS, and the pentose phosphate pathway. Concurrently, the mobilization of reactive oxygen species (ROS) scavenging systems and fine-tuning of NADPH-dependent ROS production systems in PGCs was observed. These processes were accompanied by perinuclear mobilization of ABCB1 and ABCG2 transporters and DOX retention in the perinuclear PGC compartments. Conclusions: These data demonstrate the cooperative pattern of GBM recovery from DOX-induced stress and the crucial role of metabolic reprogramming of PGCs in this process. Metabolic reprogramming enhances the efficiency of self-defense systems and increases the DOX retention capacity of PGCs, potentially reducing DOX bioavailability in the proximity of SECs. Consequently, the modulation of PGC metabolism is highlighted as a potential target for intervention in glioblastoma treatment.