Altered Mitochondrial Function Research Articles

Unveiling the molecular networks underlying cellular impairment in Saccharomyces cerevisiae: investigating the effects of magnesium oxide nanoparticles on cell wall integrity and endoplasmic reticulum stress response.

Nanoparticles, particularly magnesium oxide nanoparticles (MgO-NPs), are increasingly utilized in various fields, yet their potential impact on cellular systems remains a topic of concern. This study aimed to comprehensively investigate the molecular mechanisms underlying MgO-NP-induced cellular impairment in Saccharomyces cerevisiae, with a focus on cell wall integrity, endoplasmic reticulum (ER) stress response, mitochondrial function, lipid metabolism, autophagy, and epigenetic alterations. MgO-NPs were synthesized through a chemical reduction method, characterized for morphology, size distribution, and elemental composition. Concentration-dependent toxicity assays were conducted to evaluate the inhibitory effect on yeast growth, accompanied by propidium iodide (PI) staining to assess membrane damage. Intracellular reactive oxygen species (ROS) accumulation was measured, and chitin synthesis, indicative of cell wall perturbation, was examined along with the expression of chitin synthesis genes. Mitochondrial function was assessed through Psd1 localization, and ER structure was analyzed using dsRed-HDEL marker. The unfolded protein response (UPR) pathway activation was monitored, and lipid droplet formation and autophagy induction were investigated. Results demonstrated a dose-dependent inhibition of yeast growth by MgO-NPs, with concomitant membrane damage and ROS accumulation. Cell wall perturbation was evidenced by increased chitin synthesis and upregulation of chitin synthesis genes. MgO-NPs impaired mitochondrial function, disrupted ER structure, and activated the UPR pathway. Lipid droplet formation and autophagy were induced, indicating cellular stress responses. Additionally, MgO-NPs exhibited differential cytotoxicity on histone mutant strains, implicating specific histone residues in cellular response to nanoparticle stress. Immunoblotting revealed alterations in histone posttranslational modifications, particularly enhanced methylation of H3K4me. This study provides comprehensive insights into the multifaceted effects of MgO-NPs on S. cerevisiae, elucidating key molecular pathways involved in nanoparticle-induced cellular impairment. Understanding these mechanisms is crucial for assessing nanoparticle toxicity and developing strategies for safer nanoparticle applications.

Molecular mechanisms of mitochondria-mediated ferroptosis: a potential target for antimalarial interventions

Ferroptosis is an iron-dependent form of regulated cell death characterized by glutathione (GSH) depletion, glutathione peroxidase 4 (GPX4) inactivation, and the build-up of lipotoxic reactive species. Ferroptosis-targeted induction is a promising therapeutic approach for addressing antimalarial drug resistance. In addition to being the primary source of intracellular energy supply and reactive oxygen species (ROS) generation, mitochondria actively participate in diverse forms of regulated cell death, including ferroptosis. Altered mitochondrial morphology and functionality are attributed to ferroptosis. Diverse mitochondria-related proteins and metabolic activities have been implicated in fine-tuning the action of ferroptosis inducers. Herein, we review recent progress in this evolving field, elucidating the numerous mechanisms by which mitochondria regulate ferroptosis and giving an insight into the role of the organelle in ferroptosis. Additionally, we present an overview of how mitochondria contribute to ferroptosis in malaria. Furthermore, we attempt to shed light on an inclusive perspective on how targeting malaria parasites’ mitochondrion and attacking redox homeostasis is anticipated to induce ferroptosis-mediated antiparasitic effects.

Revisiting the Mitochondrial Function and Communication in Neurodegenerative Diseases.

Neurodegenerative disorders are distinguished by the progressive loss of anatomically or physiologically relevant neural systems. Atypical mitochondrial morphology and metabolic malfunction are found in many neurodegenerative disorders. Alteration in mitochondrial function can occur as a result of aberrant mitochondrial DNA, altered nuclear enzymes that interact with mitochondria actively or passively, or due to unexplained reasons. Mitochondria are intimately linked to the Endoplasmic reticulum (ER), and ER-mitochondrial communication governs several of the physiological functions and procedures that are disrupted in neurodegenerative disorders. Numerous researchers have associated these disorders with ER-mitochondrial interaction disturbance. In addition, aberrant mitochondrial DNA mutation and increased ROS production resulting in ionic imbalance and leading to functional and structural alterations in the brain as well as cellular damage may have an essential role in disease progression via mitochondrial malfunction. In this review, we explored the evidence highlighting the role of mitochondrial alterations in neurodegenerative pathways in most serious ailments, including Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD).

Follicular metabolic alterations are associated with obesity in mares and can be mitigated by dietary supplementation

Obesity is a growing concern in human and equine populations, predisposing to metabolic pathologies and reproductive disturbances. Cellular lipid accumulation and mitochondrial dysfunction play an important role in the pathologic consequences of obesity, which may be mitigated by dietary interventions targeting these processes. We hypothesized that obesity in the mare promotes follicular lipid accumulation and altered mitochondrial function of oocytes and granulosa cells, potentially contributing to impaired fertility in this population. We also predicted that these effects could be mitigated by dietary supplementation with a combination of targeted nutrients to improve follicular cell metabolism. Twenty mares were grouped as: Normal Weight [NW, n = 6, body condition score (BCS) 5.7 ± 0.3], Obese (OB, n = 7, BCS 7.7 ± 0.2), and Obese Diet Supplemented (OBD, n = 7, BCS 7.7 ± 0.2), and fed specific feed regimens for ≥ 6 weeks before sampling. Granulosa cells, follicular fluid, and cumulus-oocyte complexes were collected from follicles ≥ 35 mm during estrus and after induction of maturation. Obesity promoted several mitochondrial metabolic disturbances in granulosa cells, reduced L-carnitine availability in the follicle, promoted lipid accumulation in cumulus cells and oocytes, and increased basal oocyte metabolism. Diet supplementation of a complex nutrient mixture mitigated most of the metabolic changes in the follicles of obese mares, resulting in parameters similar to NW mares. In conclusion, obesity disturbs the equine ovarian follicle by promoting lipid accumulation and altering mitochondrial function. These effects may be partially mitigated with targeted nutritional intervention, thereby potentially improving fertility outcomes in the obese female.

Increased Vulnerability to Ferroptosis in FUS-ALS

Ferroptosis, a regulated form of cell death characterized by iron-dependent lipid peroxide accumulation, plays a pivotal role in various pathological conditions, including neurodegenerative diseases. While reasonable evidence for ferroptosis exists, e.g., in Parkinson’s disease or Alzheimer’s disease, there are only a few reports on amyotrophic lateral sclerosis (ALS), a fast progressive and incurable neurodegenerative disease characterized by progressive motor neuron degeneration. Interestingly, initial studies have suggested that ferroptosis might be significantly involved in ALS. Key features of ferroptosis include oxidative stress, glutathione depletion, and alterations in mitochondrial morphology and function, mediated by proteins such as GPX4, xCT, ACSL4 FSP1, Nrf2, and TfR1. Induction of ferroptosis involves small molecule compounds like erastin and RSL3, which disrupt system Xc− and GPX4 activity, respectively, resulting in lipid peroxidation and cellular demise. Mutations in fused in sarcoma (FUS) are associated with familial ALS. Pathophysiological hallmarks of FUS-ALS involve mitochondrial dysfunction and oxidative damage, implicating ferroptosis as a putative cell-death pathway in motor neuron demise. However, a mechanistic understanding of ferroptosis in ALS, particularly FUS-ALS, remains limited. Here, we investigated the vulnerability to ferroptosis in FUS-ALS cell models, revealing mitochondrial disturbances and increased susceptibility to ferroptosis in cells harboring ALS-causing FUS mutations. This was accompanied by an altered expression of ferroptosis-associated proteins, particularly by a reduction in xCT expression, leading to cellular imbalance in the redox system and increased lipid peroxidation. Iron chelation with deferoxamine, as well as inhibition of the mitochondrial calcium uniporter (MCU), significantly alleviated ferroptotic cell death and lipid peroxidation. These findings suggest a link between ferroptosis and FUS-ALS, offering potential new therapeutic targets.

Abstract 3980: Investigating the role of host obesity in promoting immunotherapy resistance

Abstract Obesity is linked to an increased risk of various cancers, including renal cell carcinoma (RCC). Many RCC patients have obesity at diagnosis and treatment initiation, and our lab has found that this significantly impairs immunotherapy outcomes. Both preclinical and clinical reports, from our lab and others, have demonstrated that obesity reduces the efficacy of CD8+ T cell-dependent immunotherapy by increasing pro-tumorigenic IL-1β. Combining anti-PD-1 based therapy with anti-IL-1β triggers the recruitment of CD8+ T cells and improves the efficacy of anti-PD-1 based immunotherapy. However, the mechanistic links between obesity and increased IL-1β production remains unknown. Our objective is to identify mechanisms promoting IL-1 β-driven immunosuppression within renal tumors of obese mice. In our in vivo studies, we utilized a BALB/c mouse model of diet-induced obesity (DIO) and lean controls in combination with the Renca-Luc RCC cell line. Using flow cytometry and western blot, we respectively assessed leukocyte populations producing IL-1β and tumor energetics. Flow cytometry revealed that intra-tumoral IL-1β is produced primarily by tumor associated macrophages (TAMS). Immunoblotting demonstrated that increased IL-1β production is linked to altered mitochondrial function and ATP production. These early findings support the hypothesis that obesity driven IL-1β expression is mediated by tumor-associated macrophages and that mitochondrial dysfunction drives immune suppression. Understanding these molecular and immune-related mechanisms may pave the way for novel strategies to reduce immunosuppression in obese RCC patients, thus improving immunotherapeutic efficacy and overall clinical outcomes. Citation Format: Henry Nnaemeka Ogbonna, Zachary Roberts, Haley Kvarnberg, Francesca Dempsey, Patrick N. Song, Anna G. Sorace, Lyse Norian. Investigating the role of host obesity in promoting immunotherapy resistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3980.

Mitochondrial Dysfunction Causes Cell Death in Patients Affected by Fragile-X-Associated Disorders.

Mitochondria are involved in multiple aspects of neurodevelopmental processes and play a major role in the pathogenetic mechanisms leading to neuro-degenerative diseases. Fragile-X-related disorders (FXDs) are genetic conditions that occur due to the dynamic expansion of CGG repeats of the FMR1 gene encoding for the RNA-binding protein FMRP, particularly expressed in the brain. This gene expansion can lead to premutation (PM, 56-200 CGGs), full mutation (FM, >200 CGGs), or unmethylated FM (UFM), resulting in neurodegeneration, neurodevelopmental disorders, or no apparent intellectual disability, respectively. To investigate the mitochondrial mechanisms that are involved in the FXD patients, we analyzed mitochondrial morphology and bioenergetics in fibroblasts derived from patients. Donut-shaped mitochondrial morphology and excessive synthesis of critical mitochondrial proteins were detected in FM, PM, and UFM cells. Analysis of mitochondrial oxidative phosphorylation in situ reveals lower respiration in PM fibroblasts. Importantly, mitochondrial permeability transition-dependent apoptosis is sensitized to reactive oxygen species in FM, PM, and UFM models. This study elucidated the mitochondrial mechanisms that are involved in the FXD phenotypes, and indicated altered mitochondrial function and morphology. Importantly, a sensitization to permeability transition and apoptosis was revealed in FXD cells. Overall, our data suggest that mitochondria are novel drug targets to relieve the FXD symptoms.

Metabolic alterations and mitochondrial dysfunction in human airway BEAS-2B cells exposed to vanadium pentoxide

Vanadium pentoxide (V+5) is a hazardous material that has drawn considerable attention due to its wide use in industrial sectors and increased release into environment from human activities. It poses potential adverse effects on animals and human health, with pronounced impact on lung physiology and functions. In this study, we investigated the metabolic response of human bronchial epithelial BEAS-2B cells to low-level V+5 exposure (0.01, 0.1, and 1 ppm) using liquid chromatography-high resolution mass spectrometry (LC-HRMS). Exposure to V+5 caused extensive changes to cellular metabolism in BEAS-2B cells, including TCA cycle, glycolysis, fatty acids, amino acids, amino sugars, nucleotide sugar, sialic acid, vitamin D3, and drug metabolism, without causing cell death. Altered mitochondrial structure and function were observed with as low as 0.01 ppm (0.2 μM) V+5 exposure. In addition, decreased level of E-cadherin, the prototypical epithelial marker of epithelial-mesenchymal transition (EMT), was observed following V+5 treatment, supporting potential toxicity of V+5 at low levels. Taken together, the present study shows that V+5 has adverse effects on mitochondria and the metabolome which may result in EMT activation in the absence of cell death. Furthermore, results suggest that high-resolution metabolomics could serve as a powerful tool to investigate metal toxicity at levels which do not cause cell death.

Abcb10 regulates murine hematopoietic stem cell potential and erythroid differentiation

Erythropoiesis in the adult bone marrow relies on mitochondrial membrane transporters to facilitate heme and hemoglobin production. Erythrocytes in the bone marrow are produced although the differentiation of erythroid progenitor cells that originate from hematopoietic stem cells (HSCs). Whether and how mitochondria transporters potentiate HSCs and affect their differentiation toward erythroid lineage remains unclear. Here, we show that the ATP-binding cassette (ABC) transporter 10 (Abcb10), located on the inner mitochondrial membrane, is essential for HSC maintenance and erythroid-lineage differentiation. Induced deletion of Abcb10 in adult mice significantly increased erythroid progenitor cell and decreased HSC number within the bone marrow (BM). Functionally, Abcb10-deficient HSCs exhibited significant decreases in stem cell potential but with a skew toward erythroid-lineage differentiation. Mechanistically, deletion of Abcb10 rendered HSCs with excess mitochondrial iron accumulation and oxidative stress yet without alteration in mitochondrial bioenergetic function. However, impaired hematopoiesis could not be rescued through the in vivo administration of a mitochondrial iron chelator or antioxidant to Abcb10-deficient mice. Abcb10-mediated mitochondrial iron transfer is thus pivotal for the regulation of physiologic HSC potential and erythroid-lineage differentiation.

The role of mitochondria in eosinophil function: implications for severe asthma pathogenesis.

Mitochondria are key metabolic hubs involved in cellular energy production and biosynthesis. ATP is generated primarily by glucose and fatty acid oxidation through the tricarboxylic acid (TCA) cycle and oxidative phosphorylation (OXPHOS) in the mitochondria. During OXPHOS there is also production of reactive oxygen species (ROS), which are involved in the regulation of cellular function. Mitochondria are also central in the regulating cell survival and death, particularly in the intrinsic apoptosis pathway. Severe asthma is a heterogeneous disease driven by various immune mechanisms. Severe eosinophilic asthma entails a type 2 inflammatory response and peripheral and lung eosinophilia, associated with severe airflow obstruction, frequent exacerbations and poor response to treatment. Mitochondrial dysfunction and altered metabolism have been observed in airway epithelial and smooth muscle cells from patients with asthma. However, the role of mitochondria in the development of eosinophilia and eosinophil-mediated inflammation in severe asthma is unknown. In this review, we discuss the currently limited literature on the role of mitochondria in eosinophil function and how it is regulated by asthma-relevant cytokines, including interleukin (IL)-5 and granulocyte-macrophage colony-stimulating factor (GM-CSF), as well as by corticosteroid drugs. Moreover, we summarise the evidence on the role of mitochondria in the regulation of eosinophils apoptosis and eosinophil extracellular trap formation. Finally, we discuss the possible role of altered mitochondrial function in eosinophil dysfunction in severe asthma and suggest possible research avenues in order to better understand their role in disease pathogenesis, and identify novel therapeutic targets.

Novel Multi-Antioxidant Approach for Ischemic Stroke Therapy Targeting the Role of Oxidative Stress.

Stroke is a major contributor to global mortality and disability. While reperfusion is essential for preventing neuronal death in the penumbra, it also triggers cerebral ischemia-reperfusion injury, a paradoxical injury primarily caused by oxidative stress, inflammation, and blood-brain barrier disruption. An oxidative burst inflicts marked cellular damage, ranging from alterations in mitochondrial function to lipid peroxidation and the activation of intricate signalling pathways that can even lead to cell death. Thus, given the pivotal role of oxidative stress in the mechanisms of cerebral ischemia-reperfusion injury, the reinforcement of the antioxidant defence system has been proposed as a protective approach. Although this strategy has proven to be successful in experimental models, its translation into clinical practice has yielded inconsistent results. However, it should be considered that the availability of numerous antioxidant molecules with a wide range of chemical properties can affect the extent of injury; several groups of antioxidant molecules, including polyphenols, carotenoids, and vitamins, among other antioxidant compounds, can mitigate this damage by intervening in multiple signalling pathways at various stages. Multiple clinical trials have previously been conducted to evaluate these properties using melatonin, acetyl-L-carnitine, chrysanthemum extract, edaravone dexborneol, saffron, coenzyme Q10, and oleoylethanolamide, among other treatments. Therefore, multi-antioxidant therapy emerges as a promising novel therapeutic option due to the potential synergistic effect provided by the simultaneous roles of the individual compounds.

Anthocyanins and their metabolites promote white adipose tissue beiging by regulating mitochondria thermogenesis and dynamics

High-fat diet (HFD) consumption and excess nutrient availability can cause alterations in mitochondrial function and dynamics. We previously showed that anthocyanins (AC) decreased HFD-induced body weight gain and fat deposition. This study investigated: i) the capacity of AC to mitigate HFD-induced alterations in mitochondrial dynamics, biogenesis, and thermogenesis in mouse subcutaneous white adipose tissue (sWAT), and ii) the underlying mechanisms of action of cyanidin-3-O-glucoside (C3G), delphinidin-3-O-glucoside (D3G), and their gut metabolites on mitochondria function/dynamics in 3T3-L1 adipocytes treated with palmitate. Mice were fed control or HFD diets, added or not with 40 mg AC/kg body weight (BW). Compared to control and AC-supplemented mice, HFD-fed mice had fewer sWAT mitochondria that presented alterations of their architecture. AC supplementation prevented HFD-induced decrease of proteins involved in mitochondria biogenesis (PPARγ, PRDM16 and PGC-1α), and thermogenesis (UCP-1), and decreased AMPK phosphorylation. AC supplementation also restored the alterations in sWAT mitochondrial dynamics (Drp-1, OPA1, MNF-2, and Fis-1) and mitophagy (BNIP3L/NIX) caused by HFD consumption. In mature 3T3-L1, C3G, D3G, and their metabolites protocatechuic acid (PCA), 4-hydroxybenzaldehyde (HB), and gallic acid (GA) differentially affected palmitate-mediated decreased cAMP, PKA, AMPK, and SIRT-1 signaling pathways. C3G, D3G, and metabolites also prevented palmitate-mediated decreased expression of PPARγ, PRDM16, PGC-1α, and UCP1. Results suggest that consumption of select AC, i.e. cyanidin and delphinidin, could promote sWAT mitochondriogenesis and improve mitochondria dynamics in the context of HFD/obesity-induced dysmetabolism in part by regulating PKA, AMPK, and SIRT-1 signaling pathways.

Immortalised murine R349P desmin knock-in myotubes exhibit a reduced proton leak and decreased ADP/ATP translocase levels in purified mitochondria

Desmin gene mutations cause myopathies and cardiomyopathies. Our previously characterised R349P desminopathy mice, which carry the ortholog of the common human desmin mutation R350P, showed marked alterations in mitochondrial morphology and function in muscle tissue. By isolating skeletal muscle myoblasts from offspring of R349P desminopathy and p53 knock-out mice, we established an immortalised cellular disease model. Heterozygous and homozygous R349P desmin knock-in and wild-type myoblasts could be well differentiated into multinucleated spontaneously contracting myotubes. The desminopathy myoblasts showed the characteristic disruption of the desmin cytoskeleton and desmin protein aggregation, and the desminopathy myotubes showed the characteristic myofibrillar irregularities. Long-term electrical pulse stimulation promoted myotube differentiation and markedly increased their spontaneous contraction rate. In both heterozygous and homozygous R349P desminopathy myotubes, this treatment restored a regular myofibrillar cross-striation pattern as seen in wild-type myotubes. High-resolution respirometry of mitochondria purified from myotubes by density gradient ultracentrifugation revealed normal oxidative phosphorylation capacity, but a significantly reduced proton leak in mitochondria from the homozygous R349P desmin knock-in cells. Consistent with a reduced proton flux across the inner mitochondrial membrane, our quantitative proteomic analysis of the purified mitochondria revealed significantly reduced levels of ADP/ATP translocases in the homozygous R349P desmin knock-in genotype. As this alteration was also detected in the soleus muscle of R349P desminopathy mice, which, in contrast to the mitochondria purified from cultured cells, showed a variety of other dysregulated mitochondrial proteins, we consider this finding to be an early step in the pathogenesis of secondary mitochondriopathy in desminopathy.

Knockdown of FAM83A to Verify Its Role in Cervical Cancer Cell Growth and Cisplatin Sensitivity.

The exploration of tumor target genes holds paramount importance for the prevention and treatment of cervical cancer. In this study, we outline the steps involved in the identification of a tumor target gene FAM83A in cervical cancer. First, the Cancer Genome Atlas dataset was employed to validate the expression and prognostic significance of FAM83A in women. A small interfering RNA (siRNA) was used for knockdown of the FAM83A gene in HeLa and C33a cells. Next, 5-ethynyl-2'-deoxyuridine (EdU) staining was conducted to determine the effects on the proliferation capabilities of the tumor cells. Wound healing and porous membrane insert assays were performed to evaluate tumor cell migration and invasion abilities. Western blotting was used to quantify apoptosis-related protein levels. JC-1 staining was employed to evaluate mitochondrial function alterations. Furthermore, cisplatin (diaminedichloroplatinum, DDP) intervention was used to assess the therapeutic potential of the target gene. Flow cytometry and colony formation assays were conducted to further validate the anticancer characteristics of the gene. As a result, FAM83A knockdown was shown to inhibit the proliferation, migration, and invasion of cervical cancer cells and sensitize these cells to cisplatin. These comprehensive methodologies collectively validate FAM83A as a tumor-associated target gene, holding promise as a potential therapeutic target in the prevention and treatment of cervical cancer.

SLE serum induces altered goblet cell differentiation and leakiness in human intestinal organoids

Human intestinal epithelial cells are the interface between luminal content and basally residing immune cells. They form a tight monolayer that constantly secretes mucus creating a multilayered protective barrier. Alterations in this barrier can lead to increased permeability which is common in systemic lupus erythematosus (SLE) patients. However, it remains unexplored how the barrier is affected. Here, we present an in vitro model specifically designed to examine the effects of SLE on epithelial cells. We utilize human colon organoids that are stimulated with serum from SLE patients. Combining transcriptomic with functional analyses revealed that SLE serum induced an expression profile marked by a reduction of goblet cell markers and changed mucus composition. In addition, organoids exhibited imbalanced cellular composition along with enhanced permeability, altered mitochondrial function, and an interferon gene signature. Similarly, transcriptomic analysis of SLE colon biopsies revealed a downregulation of secretory markers. Our work uncovers a crucial connection between SLE and intestinal homeostasis that might be promoted in vivo through the blood, offering insights into the causal connection of barrier dysfunction and autoimmune diseases.

Abstract A049: Epithelial to mesenchymal transition confers sensitivity to cytotoxic agent Ophiobolin A via alterations in mitochondrial function and metabolic pathways

Abstract Triple negative breast cancer (TNBC) is characterized by its high metastatic potential, resistance to therapeutics and elevated degree of disease reoccurrence. In patients with TNBC, metastasis occurs in approximately half of all cases and is tightly correlated with poor overall survival, made worse by limited therapeutic options. Metastatic events are hypothesized to be facilitated by the epithelial to mesenchymal transition (EMT), gaining enhanced self-renewal, migration, invasion and multidrug resistant capabilities. Thus, targeting these cells remains a primary therapeutic goal, despite significant difficulty. Previous attempts in pursuing these cells through cytotoxic chemotherapeutics or targeted agents has largely failed to significantly improve patient outcomes. However, the fungus-derived sesterterpenoid Ophiobolin A (OpA) has demonstrated nanomolar cytotoxic capabilities and a high therapeutic index, specific to EMT+cells in breast cancer. The properties conferring this sensitivity, and possible novel therapeutic target, though, remain unclear. As the drug-like small molecule presents a major therapeutic opportunity, the details of its mechanism of action must be determined. To this end, we generated mitochondrial cybrids and quantified activity in individual electron transport chain (ETC) complexes, and found OpA to act in a mitochondria-targeted manner. Expanding upon this, we designed an EMT based model of breast cancer and examined alterations in mitochondrial function and metabolic pathways. Targeted liquid chromatography-mass spectronomy of metabolites indicated significant variations in many of those involved in glycolysis, OXPHOS and glutaminolysis. Flow cytometry further revealed a significant decrease in membrane potential and increase in mitochondrial reactive oxygen species (ROS), indicating mitochondrial damage. Dynamic changes between OXPHOS and glycolysis were also detected via Seahorse Bioanalyzer. Transmission electron microscopy (TEM) images and fluorescent microscopy showed distinct alterations in mitochondrial morphology, spatial dynamics and network integrity. Finally, using targeted fluorescent staining, an increase in mitochondrial labile iron was uncovered. This work reveals novel metabolic variations in the context of EMT and exploitable therapeutic targets. Thus, based on these EMT-specific responses, we conclude that EMT imparts distinct alterations to mitochondrial function and metabolic pathways, conferring sensitivity to the cytotoxic effects of OpA. Citation Format: Haleigh Parker, Kayla Haberman, Alexander Kornienko, Antonio Evidente, Daniel Romo, Benny Kaipparettu, Joseph Taube. Epithelial to mesenchymal transition confers sensitivity to cytotoxic agent Ophiobolin A via alterations in mitochondrial function and metabolic pathways [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr A049.

Research progress in mitochondrial quality control in schizophrenia.

Mitochondria are the main site of energy metabolism within cells, generating a substantial amount of ATP to supply energy to the human body. Research has shown that alterations in mitochondrial structure and function exist in individuals with schizophrenia, suggesting their potential impact on the onset of psychiatric disorders and clinical treatment efficacy. Therefore, understanding the research progress on the genetic mechanisms, pathological processes, image manifestations of schizophrenia and mitochondrial quality control, and summarizing the relevant evidence of mitochondrial-related targets as potential therapeutic targets for schizophrenia, can provide references for further research.

Data-Independent Acquisition Proteomics and N-Terminomics Methods Reveal Alterations in Mitochondrial Function and Metabolism in Ischemic-Reperfused Hearts.

Myocardial ischemia-reperfusion (IR) (stunning) injury triggers changes in the proteome and degradome of the heart. Here, we utilize quantitative proteomics and comprehensive degradomics to investigate the molecular mechanisms of IR injury in isolated rat hearts. The control group underwent aerobic perfusion, while the IR injury group underwent 20 min of ischemia and 30 min of reperfusion to induce a stunning injury. As MMP-2 activation has been shown to contribute to myocardial injury, hearts also underwent IR injury with ARP-100, an MMP-2-preferring inhibitor, to dissect the contribution of MMP-2 to IR injury. Using data-independent acquisition (DIA) and mass spectroscopy, we quantified 4468 proteins in ventricular extracts, whereby 447 proteins showed significant alterations among the three groups. We then used subtiligase-mediated N-terminomic labeling to identify more than a hundred specific cleavage sites. Among these protease substrates, 15 were identified following IR injury. We identified alterations in numerous proteins involved in mitochondrial function and metabolism following IR injury. Our findings provide valuable insights into the biochemical mechanisms of myocardial IR injury, suggesting alterations in reactive oxygen/nitrogen species handling and generation, fatty acid metabolism, mitochondrial function and metabolism, and cardiomyocyte contraction.

Vutiglabridin Alleviates Cellular Senescence with Metabolic Regulation and Circadian Clock in Human Dermal Fibroblasts.

The process of cellular senescence, which is characterized by stable cell cycle arrest, is strongly associated with dysfunctional cellular metabolism and circadian rhythmicity, both of which are reported to result from and also be causal to cellular senescence. As a result, modifying any of them-senescence, metabolism, or the circadian clock-may affect all three simultaneously. Obesity accelerates aging by disrupting the homeostasis of reactive oxygen species (ROS) via an increased mitochondrial burden of fatty acid oxidation. As a result, if senescence, metabolism, and circadian rhythm are all linked, anti-obesity treatments may improve metabolic regulation while also alleviating senescence and circadian rhythm. Vutiglabridin is a small molecule in clinical trials that improves obesity by enhancing mitochondrial function. We found that chronic treatment of senescent primary human dermal fibroblasts (HDFs) with vutiglabridin alleviates all investigated markers of cellular senescence (SA-β-gal, CDKN1A, CDKN2A) and dysfunctional cellular circadian rhythm (BMAL1) while remarkably preventing the alterations of mitochondrial function and structure that occur during the process of cellular senescence. Our results demonstrate the significant senescence-alleviating effects of vutiglabridin, specifically with the restoration of cellular circadian rhythmicity and metabolic regulation. These data support the potential development of vutiglabridin against aging-associated diseases and corroborate the intricate link between cellular senescence, metabolism, and the circadian clock.

Difference in the cellular response following THP-1 derived phagocytic monocyte cells exposure to commercial aluminum-based adjuvants and aluminum-containing vaccines

BackgroundAluminum-based adjuvants (ABAs) enhance the immune response following vaccine injection. Their mechanisms of action are not fully understood, and their bio-persistency have been described associated with long-term adverse effects. MethodsWe evaluated and compared the cellular effects of the two main ABAs and whole vaccines on ATP production, ROS generation and cytokines production (IL-6 and IL-10), using THP-1 cells. ResultsABAs altered the cell energy metabolism by increasing ROS production after 24 h and reducing ATP production after 48 h. In addition, both ABAs and whole vaccines induced different kinetics of IL-6 production, whereas only ABAs induced IL-10 secretion. ConclusionThis study showed clearly, for a first time, a difference in cellular response to the ABAs and whole vaccines which should be taken into consideration in future studies focusing on the effect of ABA in vaccines. Future studies on ABAs should also pay attention to mitochondrial function alterations following exposure to ABA-containing vaccines.