bims-polgdi Biomed News
on POLG disease
Issue of 2026–03–22
35 papers selected by
Luca Bolliger, lxBio



  1. Eur J Neurosci. 2026 Mar;63(6): e70463
      Mitochondria are central regulators of cellular metabolism, calcium homeostasis and survival. Owing to the brain's exceptional energy demand, mitochondrial dysfunction is tightly linked to neurodegenerative and neuroinflammatory disorders. Recent evidence challenges the traditional view of mitochondria as strictly cell-autonomous organelles, revealing that they can be exchanged between cells via intercellular transfer by extracellular vesicles, gap junctions or tunnelling nanotubes (TNTs) as part of an adaptive mechanism of metabolic support and signalling. Among the pathways mediating this intercellular exchange, TNTs-thin, actin-rich cytoplasmic bridges-have emerged as key conduits for mitochondrial transfer in the nervous system. TNTs enable bidirectional exchange of mitochondria between neurons, glia and vascular cells, thereby promoting bioenergetic recovery after injury and modulating immune and inflammatory responses. This review summarizes current evidence for TNT-mediated mitochondrial transfer in the brain and highlights the underlying molecular mechanisms that coordinate mitochondrial movement, including cytoskeletal dynamics, mitochondrial trafficking machinery and stress-induced signalling cascades. While mitochondrial donation can restore metabolic balance and promote neuroprotection, it may also facilitate the spread of pathological proteins, contributing to disease progression. Understanding the underlying molecular mechanism of TNT-mediated mitochondrial transfer provides a new framework for exploring metabolic communication and cellular resilience in the brain. By emphasizing emerging conceptual and mechanistic insights, we outline how advancing this field could pave the way for the development of innovative therapeutic strategies for neurodegenerative and neuroinflammatory disorders.
    Keywords:  Miro1/2; actin dynamics; cell–cell connectivity; cytoskeletal remodelling; intercellular communication
    DOI:  https://doi.org/10.1111/ejn.70463
  2. Annu Rev Biochem. 2026 Mar 20.
      Damage to mitochondria imparts multifaceted cellular stress that extends beyond bioenergetic deficit. One newly emerged example is mitochondrial precursor overaccumulation stress (mPOS). mPOS is marked by impaired mitochondrial protein import, causing the toxic accumulation and aggregation of unimported mitochondrial precursor proteins in the cytosol. Analogous to the well-studied endoplasmic reticulum stress, which blocks proteins from leaving the cell, mPOS can impose a drastic proteostatic burden in the cytosol and closely interconnects with cell signaling pathways. Here, we review how researchers discovered mPOS and discuss its central importance in several major mitochondria-induced stress signaling pathways. We then focus on the emerging field of mPOS in cell demise and human disease, and we present recent evidence that mPOS can affect cell fitness and survival independent of bioenergetics. Looking forward, mPOS may provide a complementary or alternative pathogenic mechanism to bioenergetic deficit for classic mitochondriopathy and many aging-associated degenerative diseases involving mitochondrial stress.
    DOI:  https://doi.org/10.1146/annurev-biochem-051424-061016
  3. Genome Biol Evol. 2026 Mar 16. pii: evag067. [Epub ahead of print]
      Why do some species live for mere months, while others persist for centuries? A leading explanation implicates mitochondria. The mitochondrial theory of aging predicts that mitochondrial efficiency diminishes with age due to the accumulation of mutations within mitochondrial DNA (mtDNA). While experimental evidence for this theory is mixed, evolutionary analyses offer an ideal opportunity to determine if mitochondrial substitution rates are linked to longevity. Here, we explored the relationship between mtDNA evolution and species' lifespans across four clades-Aves, Actinopterygii, Bivalvia, and Sebastidae-using five normalization strategies. Across most methods, long-lived vertebrates showed reduced synonymous and nonsynonymous substitution rates, suggesting lower mtDNA mutation. However, we found that the strength and direction of these relationships varied drastically depending on the normalization approach used (i.e., correcting for divergence, generation time, and phylogeny). We also analyzed mtDNA mutation spectra and found similar patterns in long- and short-lived species, suggesting decreased rates of mtDNA mutations in long-lived species are not due to suppression of specific mutation processes, as predicted from the free-radical theory of aging. We also find little evidence for a relationship between selection on mitochondrial protein-coding genes and lifespan. Our results align with the idea that decreased mutation rates may help preserve mitochondrial integrity in long-lived vertebrate species, but that these species have not been selected to have particularly efficient OXPHOS or protection against a specific mitochondrial mutation process. Together, these findings underscore the critical link between mitochondrial stability and lifespan, and highlight the power of natural systems in this field.
    Keywords:  Mitochondrial DNA; comparative genomics; generation time; longevity; phylogenetic comparative methods; substitution rates
    DOI:  https://doi.org/10.1093/gbe/evag067
  4. Front Psychiatry. 2026 ;17 1792382
      
    Keywords:  NACC1 gene; intellectual disability (ID); multiple mitochondrial dysfunctions syndrome 4; pyridoxine-dependent epilepsy; quality of life of children with trisomy 21; rare genetic disorders
    DOI:  https://doi.org/10.3389/fpsyt.2026.1792382
  5. Redox Biol. 2026 Mar 11. pii: S2213-2317(26)00122-9. [Epub ahead of print]92 104124
      Mitochondrial ferritin (FtMt), first identified by Levi et al., is an iron-storage protein with high homology with cytoplasmic ferritin. It is mainly expressed in metabolically active tissues and exhibits distinct physiological and biochemical properties compared cytoplasmic ferritin. Over the past few decades, significant attention has been drawn to the unique structural and functional characteristics of FtMt that differentiates it from conventional ferritin. Mitochondrial ferritin specifically located on the mitochondrial exhibits unique advantages in mitochondrial redox balance through isolating iron within mitochondria, reducing oxidative stress and maintaining mitochondrial homeostasis. Moreover, it modulates the labile iron pool within mitochondria, facilitating the biosynthesis of iron-sulfur clusters and supporting cellular respiration. This review comprehensively discusses the pivotal function of FtMt in regulating mitochondrial redox homeostasis and its impact on cell fate decisions, specifically, its influence on apoptosis, ferroptosis through alterations in mitochondrial integrity. We also summarize recent advances in understanding the association between FtMt dysregulation and various diseases, emphasizing its implications in neurodegenerative diseases, cardiovascular disorders and cerebrovascular pathologies. By critically evaluating emerging evidence, this article aims to provide translational insights into targeting FtMt and mitochondrial redox homeostasis as therapeutic strategies for mitigating these clinically significant diseases.
    Keywords:  Cell death; Iron; Mitochondrial ferritin; Neurodegenerative disease; Redox
    DOI:  https://doi.org/10.1016/j.redox.2026.104124
  6. Mutat Res Rev Mutat Res. 2026 Mar 17. pii: S1383-5742(26)00003-7. [Epub ahead of print]797 108587
      Aging is a progressive and irreversible physiological process driven by a complex network of interrelated molecular and cellular mechanisms. Among these, cellular senescence and chronic inflammation, as two core hallmarks of aging, are interlinked and jointly promote the development and progression of aging. However, the precise molecular crosstalk between these two processes remains unclarified. Mitochondrial DNA (mtDNA), as the only cytoplasmic DNA, has recently emerged as a pivotal "bridge" linking cellular senescence and chronic inflammation through various mechanisms. Anchored on the unique characteristics of mtDNA, this review systematically elucidates its central roles in mitochondrial dysfunction and oxidative stress, with a particular emphasis on the dynamic changes of mtDNA within the cytosol and extracellular space that construct and amplify the cellular "inflammation-senescence" coupling network. Furthermore, we propose a conceptual framework linking mtDNA mutation/damage to the cellular senescence and the propagation of chronic inflammation. Finally, we discuss the therapeutic potential of targeting mtDNA dynamics and highlight key challenges and future directions in this emerging field, offering novel insights for mitigating aging and age-related diseases.
    Keywords:  Aging-related diseases; Cellular senescence; Chronic inflammation; Mitochondrial DNA; Therapeutic intervention
    DOI:  https://doi.org/10.1016/j.mrrev.2026.108587
  7. Mitochondrion. 2026 Mar 16. pii: S1567-7249(26)00040-1. [Epub ahead of print] 102150
      Primary mitochondrial disorders are clinically and genetically heterogeneous and remain underdiagnosed in resource-limited settings. We performed a retrospective observational study (March 2016-January 2024) at a tertiary neurology center in Eastern India to characterize the clinical, biochemical, neuroimaging, electrophysiological, and molecular features of suspected mitochondrial disease and to explore interpretable machine-learning approaches for syndromic stratification. Forty-eight patients from 42 unrelated families were classified as MELAS (n = 17), chronic progressive external ophthalmoplegia (CPEO; n = 14), Leber hereditary optic neuropathy (LHON; n = 10), or Leigh syndrome (n = 7). Mean age at presentation was 23.9 years (range: 9 months-60 years), with a slight male predominance. Neuroimaging was abnormal in 23/48 (47.9%) and showed syndrome-concordant patterns, including stroke-like cortical lesions in MELAS and symmetric basal ganglia involvement in Leigh syndrome; brain MRI was typically normal in CPEO. Elevated blood and/or cerebrospinal fluid lactate was common, and electroencephalographic abnormalities were concentrated in MELAS and Leigh syndrome. Targeted molecular testing in a subset identified pathogenic mtDNA variants consistent with phenotype, including MT-TL1 variants in MELAS, m.11778G>A in MT-ND4 in LHON, and m.8993T>G in MT-ATP6 in Leigh syndrome; no mtDNA deletions were detected in tested CPEO cases. Decision tree and random forest models highlighted clinically intuitive discriminators (e.g., visual loss, external ophthalmoplegia/ptosis, and seizure phenotype), supporting their potential role as transparent triage tools for targeted molecular evaluation. This cohort provides the first detailed characterization of mitochondrial syndromes in Eastern India and supports a pragmatic diagnostic framework integrating bedside phenotyping, targeted assays, and interpretable machine learning.
    Keywords:  Chronic progressive external ophthalmoplegia; Genetic diagnosis; Leber hereditary optic neuropathy; Leigh syndrome; MELAS; Machine learning; Mitochondrial disease; Neuroimaging; Oxidative phosphorylation; South Asia
    DOI:  https://doi.org/10.1016/j.mito.2026.102150
  8. Front Pharmacol. 2026 ;17 1723748
      Mitochondria act as a central integrative hub for oxidative phosphorylation, calcium homeostasis and metabolic signaling, reflecting their evolutionary origin from an α-proteobacterial endosymbiont. Although nearly 90% of their ancestral genes have been transferred to the nuclear genome, their role extends far beyond energy production. Emerging evidence positions mitochondria as active modulators of stress responses, which we term the "Mito-Mood Hypothesis." This framework proposes that mitochondrial dynamics actively regulate gene expression and signaling, thereby shaping vulnerability to mood disorders such as depression, dysthymia, and seasonal affective disorder. Consistent with this view, patients with major depressive disorders show altered expression of nuclear-encoded mitochondrial genes, linking bioenergetics directly to psychiatric risk. We further discuss how oxidative phosphorylation (OXPHOS) modulates neurotransmitter cycles and how mitohormesis-adaptive responses to mild mitochondrial stress-can enhance resilience and cognition. Beyond psychiatry, mitochondrial vulnerability manifests in clinical settings: patients with mitochondrial diseases face elevated anesthetic risk, where agents such as propofol or volatile anesthetics may precipitate life-threatening metabolic crises. Collectively, these insights underscore mitochondria as central regulators of human health and highlight novel therapeutic opportunities bridging mood disorders and perioperative medicine.
    Keywords:  circadian cycle; mitochondria; mitochondrial dynamics; mood disorders; neurotransmission; oxidative phosphorylation; perioperative stress
    DOI:  https://doi.org/10.3389/fphar.2026.1723748
  9. Transl Res. 2026 Mar 14. pii: S1931-5244(26)00062-9. [Epub ahead of print]
      Mitochondria are fundamental organelles that regulate cellular homeostasis through energy production, metabolic integration, and signaling cascades. Beyond their bioenergetic role, mitochondrial dysfunction is increasingly recognized as a pivotal instigator of PANoptosis, a novel, coordinated inflammatory cell death pathway that amalgamates key features of pyroptosis, apoptosis, and necroptosis. This integrated cell death is executed by multiprotein complexes termed PANoptosomes, which are nucleated by specific sensors like ZBP1, AIM2, and NLRC5. Central to this process is the release of mitochondrial danger signals, including reactive oxygen species (ROS) and mitochondrial DNA (mtDNA), which act as potent upstream triggers. For instance, ROS can directly oxidize and activate necroptotic mediators like RIPK1, while cytosolic mtDNA engages innate immune sensors such as cGAS-STING and inflammasomes, thereby initiating PANoptosome assembly. Concurrently, defects in core mitochondrial processes including impaired oxidative phosphorylation, disrupted dynamics (fission/fusion), and faulty mitophagy exacerbate these inflammatory signals, creating a permissive environment for PANoptosis. This mitochondrial-PANoptosis axis is implicated in the pathogenesis of a broad spectrum of diseases. Consequently, therapeutic strategies targeting mitochondrial integrity or specific PANoptotic components hold significant promise for mitigating pathological inflammation and cell loss. This review focuses on the molecular mechanisms linking mitochondrial dysfunction to PANoptosis and explores the translational potential of this interplay to reshape therapeutic approaches in diseases.
    Keywords:  & Mitochondrial dysfunction; Cell death; Immune; PANoptosis; Therapeutics
    DOI:  https://doi.org/10.1016/j.trsl.2026.03.004
  10. Cell Rep Methods. 2026 Mar 13. pii: S2667-2375(26)00038-X. [Epub ahead of print] 101338
      The neuroprotective transfer of mitochondria from astrocytes to neurons has been primarily investigated by labeling astrocytic mitochondria with the dye MitoTracker. Here, we labeled astrocytic mitochondria with both a genetically encoded fluorophore (GFP) and MitoTracker dye and then imaged neurons immediately after co-culture with astrocytes or astrocyte-conditioned media (ACM). We report that MitoTracker transfers to neurons from both astrocytes and ACM, independently of mitochondrial transfer. Our observations provide an essential caveat to the use of this reagent and suggest that the investigation of astrocyte-neuron mitochondrial transfer, and other systems in which contact-independent transfer has been reported, requires the use of alternative labeling techniques.
    Keywords:  CP: cell biology; CP: neuroscience; MitoTracker; astrocyte; intercellular mitochondrial transfer; mitochondria; neuron
    DOI:  https://doi.org/10.1016/j.crmeth.2026.101338
  11. Biochemistry (Mosc). 2026 Feb;91(2): 253-273
      Mitochondria are semi-autonomous, multifunctional organelles that supply cells with energy. They are highly dynamic structures, capable of moving, fusing, dividing, and forming branched networks. The number, density, and complexity of mitochondrial network are unique to each cell type and reflect cellular demands for ATP and other mitochondria-dependent metabolites. Mitochondrial dysfunction is a hallmark of many neurodegenerative diseases; however, the relationships between neurodegeneration and mitochondrial morphogenesis, intracellular localization, and dynamics remain incompletely understood. Interpretation and comparison of published data are complicated by the diversity of analytical approaches used to study mitochondrial behavior. In this research, we investigated the effects of a pathogenic mutation in the huntingtin protein (HTT), which causes Huntington's disease (HD), on mitochondrial morphology and motility, with particular emphasis on associated disruptions in the cytoskeletal organization. We performed a systematic evaluation of automated mitochondrial analysis tools and selected MiNA, TrackMate, and JACoP as the optimal platforms for quantitative assessment of the effects of mutant HTT (mHTT) on the mitochondrial morphology, motility, and interaction with cytoskeletal components and identification of specific disruptions directly related to HD pathogenesis. Our analysis revealed that mitochondria in mHTT-expressing cells are significantly shorter, more branched, and less motile than in control cells. Moreover, their interactions with microtubules and vimentin intermediate filaments are markedly altered. Together, these findings establish a link between HD and specific defects in the mitochondrial network, thus contributing to understanding cellular mechanisms of HD development, and suggest that mHTT disrupts the interaction of mitochondria with cytoskeletal components responsible for their movement and distribution in the cell, thereby negatively affecting mitochondrial motility and morphology.
    Keywords:  Huntington’s disease; huntingtin; mitochondrial dynamics; neurodegenerative diseases
    DOI:  https://doi.org/10.1134/S0006297925602850
  12. Cell. 2026 Mar 18. pii: S0092-8674(26)00230-8. [Epub ahead of print]
      Mitochondrial transplantation holds significant potential for the treatment of mitochondrial diseases. However, how to efficiently deliver exogenous mitochondria to somatic cells or tissues remains unresolved. We present a mitochondrial transplantation approach to deliver mitochondria into the cells and tissues of mice and monkeys with high efficiency, based on encapsulating mitochondria with vesicles derived from the plasma membrane of erythrocytes. Treatment with encapsulated mitochondria complemented the loss, deletion, or mutation of mitochondrial DNA, thereby rescuing the associated bioenergetic and biochemical defects in patient-derived cells with mitochondrial disorders. Furthermore, mitochondrial capsules rescued the mitochondrial DNA depletion syndrome and Leigh syndrome in Dguok-/- and Ndufs4-/- mouse models, respectively. Moreover, in a mouse model of Parkinson's disease, mitochondrial capsules rescued neuron loss, improved motor skills, and restored mitochondrial function in the affected brain regions. Our study demonstrates the potential of this mitochondrial capsule as a treatment for mitochondrial disorders and proposes an "organelle therapy" strategy in regenerative medicine.
    Keywords:  Parkinson’s disease; degenerative disease; extracellular vesicle; mitochondria; mitochondrial diseases; mitochondrial transfer; mtDNA depletion syndrome; mtDNA mutation; organelle therapy
    DOI:  https://doi.org/10.1016/j.cell.2026.02.023
  13. Front Mol Biosci. 2026 ;13 1774015
      Since its discovery, cell-free mitochondrial DNA (cf-mtDNA) has emerged as a promising non-invasive molecular marker for disease diagnosis and prognosis. However, the biological origins of cf-mtDNA remain incompletely understood, which limits its clinical applications. This review comprehensively summarizes the molecular characteristics, release mechanisms, and diagnostic applications of cf-mtDNA. By discussing standardization of cf-mtDNA detection methods, this review aims to provide theoretical foundations for clinical translation of this emerging biomarker.
    Keywords:  body fluids; cf-mtDNA; molecular features; molecular markers; release mechanism
    DOI:  https://doi.org/10.3389/fmolb.2026.1774015
  14. Nature. 2026 Mar 19.
      
    Keywords:  Cell biology; Gene therapy; Medical research; Metabolism
    DOI:  https://doi.org/10.1038/d41586-026-00869-2
  15. Front Public Health. 2026 ;14 1743598
       Background: Rare diseases (RDs) pose a significant public health concern, particularly in Poland, where awareness among healthcare professionals, educators, and the general public remains low. Rare disease patient advocacy groups (RDPAGs), often led by caregivers, play a vital yet under recognized role in addressing these gaps through informal education and advocacy. This study explores how RDPAGs help fill systemic gaps in RD-related education.
    Methods: This qualitative descriptive study draws on 11 interviews with leaders of Polish RDPAGs engaged in advocacy, education, and public engagement. Interviews were analysed using Reflexive Thematic Analysis, following Braun and Clarke's six-phase framework, and reported in line with COREQ guidelines.
    Results: The analysis identified four interrelated themes describing the educational and advocacy practices of RDPAGs. Participants portrayed RDPAGs as: (1) acting as ambassadors of knowledge across sectors by translating scientific and experiential expertise into accessible information; (2) supporting families through lived experience by providing curated resources, peer mentoring, and practical guidance, particularly following diagnosis; (3) engaging with and sometimes challenging professional expertise by sharing caregiver-informed knowledge, co-developing materials, and initiating dialogue with healthcare and education professionals; and (4) raising public awareness and engaging in policy-oriented advocacy through campaigns and inter-organizational collaboration. Collectively, participants described these practices as addressing systemic knowledge gaps and supporting cross-sectoral care navigation.
    Conclusion: The findings indicate that healthcare, education, and policy systems in Poland already rely substantially on the informal educational and advocacy work of RDPAGs. Formal recognition and support may help stabilize these contributions, provided that issues of sustainability, role boundaries, and uneven organizational burdens are taken into account.
    Keywords:  advocacy; awareness-raising; education; experiential knowledge; knowledge brokerage; patient advocacy groups; public engagement; rare disease patient advocacy groups
    DOI:  https://doi.org/10.3389/fpubh.2026.1743598
  16. FASEB J. 2026 Mar 31. 40(6): e71609
      The ketogenic diet (KD), a high-fat, low-carbohydrate intervention, is well established for drug-resistant epilepsy and is increasingly explored in neurodegenerative disorders. KD reduces neuronal hyperexcitability through enhanced γ-aminobutyric acid (GABA)ergic transmission and modulation of neurotransmitter balance, underlying its efficacy in refractory epilepsy. Beyond seizure control, emerging evidence suggests KD may influence disease processes in conditions such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis, and Huntington's disease. Preclinical studies indicate that KD can modulate mitochondrial bioenergetics, oxidative stress, neuroinflammation, neurotransmitter signaling, and gut-brain interactions, though these effects are highly context-dependent and primarily derived from cellular and animal models. Clinical data remain limited, heterogeneous, and short-term, with small cohorts and variable outcome measures. Sustaining adherence and assessing long-term safety remain significant challenges in patient populations. This review summarizes recent experimental and clinical findings, highlighting the molecular and cellular mechanisms through which KD exerts neuroprotective effects. We also evaluate translational evidence and discuss the potential utility of KD as an adjunctive intervention in neurological disease management.
    Keywords:  Alzheimer's disease; Huntington's disease; Parkinson's disease; amyotrophic lateral sclerosis; drug‐resistant epilepsy; ketogenic diet; multiple sclerosis; neurodegeneration
    DOI:  https://doi.org/10.1096/fj.202503317R
  17. Nat Commun. 2026 Mar 17.
      Understanding the functional mechanisms of membrane protein complexes requires structural analysis within their native membrane environment. Here, we applied cryo-electron microscopy to determine the structures of FoF1 ATP synthase and respiratory supercomplexes (SCs) on sub-mitochondrial particles (SMPs) isolated from bovine heart mitochondria. Most FoF1 complexes were observed as dimers stabilized by the regulatory factor IF₁, and a tetrameric assembly comprising two FoF1-IF₁ dimers arranged linearly was also identified. This finding indicates that the tetrameric units of FoF1 are present in the mitochondrial inner membrane and contribute to shaping cristae tips in mammalian mitochondria. Fo domain maps resolve the e-subunit- c₈-ring interface and show no discrete density for a tightly bound lipid within the c₈-ring. In addition to the previously reported SCs compositions CI₁CIII₂CIV₁ and CI₁CIII₂CIV₂, our analysis identified an additional assembly with the composition CI₁CIII₂CIV₃, as well as a CI₂CIII₂CIV₆ mega-complex. This approach enables rapid structural determination of FoF1 ATP synthase and SCs from minimal membrane fractions, providing a foundation for elucidating the molecular basis of metabolic disorders and mitochondrial diseases at the level of higher-order architecture.
    DOI:  https://doi.org/10.1038/s41467-026-70578-x
  18. iScience. 2026 Mar 20. 29(3): 115111
      Barth syndrome, a rare X-linked genetic disorder, features early-onset cardiomyopathy. The causal gene, TAFAZZIN, encodes a transacylase that mediates the acyl chain remodeling of cardiolipin, a critical phospholipid in the inner mitochondrial membrane. While Barth syndrome exhibits hallmark cardiolipin abnormalities, the precise mechanisms linking TAFAZZIN deficiency and disturbed cardiolipin metabolism to progressive cardiac dysfunction remain unclear. In this study, we modeled Barth syndrome cardiomyopathy in human induced pluripotent stem cell-derived cardiomyocytes with in vitro maturation treatments that simulate heart developmental stimuli. We found that cardiomyocyte maturation involves progressive cristae dynamics associated with protein and lipid alterations in the inner mitochondrial membrane. TAFAZZIN-deficient cardiomyocytes fail to adapt to the developmental stimuli, resulting in damaged cristae, compromised mitochondrial respiration, and cardiomyocyte dysfunction. These results demonstrate that TAFAZZIN deficiency perturbs functional and structural development of mitochondria, which may contribute to mitochondrial dysfunction and associated childhood progression to cardiomyopathy in Barth syndrome.
    Keywords:  Biological sciences; Cell biology; Molecular biology
    DOI:  https://doi.org/10.1016/j.isci.2026.115111
  19. Mitochondrion. 2026 Mar 13. pii: S1567-7249(26)00037-1. [Epub ahead of print]89 102147
      Mitochondria are morphologically and functionally heterogeneous and dynamically adapt to the current metabolic status of their hosting cell. Moreover, they are prominent sources but also sensitive targets of redox modulation and oxidative stress. Such subcellular ROS/redox signals are considered pivotal aspects in health and disease. Yet, their deciphering requires advanced optical tools. Here we took advantage of transgenic redox-indicator mice expressing a mitochondria-targeted reduction/oxidation-sensitive green fluorescent protein (roGFPm) in excitatory projection neurons. By excitation-ratiometric two-photon microscopy we quantified in acute brain slices the redox conditions of individual mitochondria. After developing adequate redox sensor calibrations and solving laser-mediated bleaching issues, we finally chose caudoputamen, which showed the most promising mitochondrial arrangement for our imaging approach. Confirming the reliability of single-mitochondria redox imaging, we characterized the interplay of redox state and mitochondrial morphology. In general, roGFPm was more oxidized in spherical than in filamentous mitochondria. Acute hypoxia reverted mitochondria to a more roundish shape and evoked a reducing shift. Furthermore, the fraction of spherical mitochondria increased with aging. Around postnatal day (pd)350, a significantly higher fraction of roundish mitochondria was present in females than in males. In addition, from pd150 on, female mice showed lower degrees of roGFPm oxidation than males. Both findings might be linked to estrogen levels, which decrease in female mice with reproductive senescence around pd350. In view of the pivotal role of mitochondria for cellular wellbeing and their involvement in various neuropathologies, the established single-organelle redox-imaging approach will foster further detailed studies.
    Keywords:  2-photon microscopy; Aging; Hypoxia; Mitochondria; Reactive oxygen species; Redox imaging; roGFP
    DOI:  https://doi.org/10.1016/j.mito.2026.102147
  20. Aging Cell. 2026 Mar;25(3): e70445
      During aging, decreased intestinal barrier function and its ability to synthesize metabolites are closely associated with various age-related diseases. However, the mechanism by which impaired intestinal synthesis contributes to gut-liver axis aging remains unclear. This study reveals that aging induces a mitochondrial energy crisis and defective membrane localization of ABCA1, significantly inhibiting the biosynthesis of high-density lipoprotein 3 (HDL3) in the intestine. Exogenous supplementation with β-nicotinamide mononucleotide (NMN) restores intestinal NAD+ homeostasis, enhances oxidative phosphorylation efficiency, and promotes ATP-dependent lipid transport, thereby rejuvenating the production of gut-derived HDL3. Further investigations demonstrate that gut-originated HDL3 neutralizes lipopolysaccharide (LPS) in the liver and attenuates TLR4-mediated inflammatory cascades, ultimately ameliorating age-related liver injury. These findings elucidate a novel mechanism whereby NMN modulates the NAD+-mitochondria-ABCA1-HDL3 axis to preserve gut-liver axis function, offering a promising therapeutic strategy for mitigating aging-related pathologies in this metabolic cross-talk.
    Keywords:  NAD+; NMN; aging; gut‐derived HDL3; gut–liver axis; mitochondrial function
    DOI:  https://doi.org/10.1111/acel.70445
  21. Ther Innov Regul Sci. 2026 Mar 18.
       INTRODUCTION: Access to cross-border clinical trials may represent the sole therapeutic option for children living with rare diseases for which no approved medicines exist. Many children are excluded from participation in trials due to language restrictions. There are insufficient comprehensive analyses of the experiences and preferences of parents across Europe concerning participation and exclusion of their child in international clinical trials, particularly regarding language support during enrollment in cross-border clinical research studies.
    METHODS: An anonymous online survey was designed and translated into 22 official European languages to collect data from parents of children living with a disease across Europe. The survey included five sections: (1) sociodemographic information; (2) experience participating in a clinical trial; (3) experience in cases where the patient was unable to take part in a study abroad; (4) experience participating in a clinical trial abroad; and (5) preferences regarding decentralized trial options.
    RESULTS: 1,436 responses were analyzed from parents across 34 European countries.
    KEY FINDINGS: 55.7% of the parents reported being able to communicate in English. 10.7% had prior clinical trial experience, of whom 30.1% traveled abroad to enable their child to participate. Among those reporting being excluded from cross-border trials, 34.7% cited language barriers or country of residence as the reason. Most families expressed a strong willingness to accept decentralized trial options, regardless of where the study may be conducted.
    CONCLUSIONS: Accommodating language translation to permit participation in a clinical trial abroad is feasible. While a significant percentage of caregivers of pediatric patients in Europe could communicate in English, approximately one-third of those excluded from clinical trials cited language barriers or country of residence as the reason. When translation was required, the most commonly offered solution was the use of professional interpreters, an accommodation that could enable broader patient participation in essential research.
    Keywords:  Cross-border clinical trials; Informed consent process; Mother tongue; Parents’ preferences; Patient reported outcomes measures (PROMs); Preferred language; Quality of life scales; Translation
    DOI:  https://doi.org/10.1007/s43441-026-00942-y
  22. Front Aging Neurosci. 2026 ;18 1771904
      The gut microbiome influences brain function through the gut-brain axis via synthesis of neurotransmitters, production of metabolites affecting epithelial barrier integrity and immune modulation and signaling through the vagus nerve. In humans, microbiome diversity reflects healthy aging and predicts survival, while dysbiosis is increasingly implicated in neurodegenerative conditions including Alzheimer's disease, Parkinson's disease, multiple sclerosis, and ALS. Fecal transplant studies in germ-free mice demonstrate that microbiome alterations are sufficient to induce cognitive and neuropathological phenotypes, supporting causality in preclinical models. Genetic risk factors and environmental exposures affect both neurodegeneration risk and microbiome composition. In this review, we synthesize evidence from human cohorts and preclinical models on the gut-brain axis in cognitive health and disease. We then present a methodological framework for diet-microbiome-cognition research, addressing causal inference through mediation analysis, supervised approaches for deriving diet scores, validation strategies, and individual heterogeneity. This framework can guide development of microbiome-targeted dietary interventions to improve cognitive outcomes.
    Keywords:  Alzheimer’s disease; Parkinson’s disease; cognition; diet questionnaire; gut microbiome
    DOI:  https://doi.org/10.3389/fnagi.2026.1771904
  23. Front Neurosci. 2026 ;20 1768545
      There is great anticipation that gene therapies can offer solutions to many neurological diseases. Already, much is known about therapeutic targets and how they would need to be manipulated to mitigate disease. For such gene therapies to move to the clinic, potent CNS delivery vehicles are needed. One line of investigation focuses on adeno-associated viruses (AAV) to address this need. In particular, blood-brain barrier (BBB)-penetrant AAV capsids are of interest due to the relative ease of their intravenous administration. This review will introduce this topic and provide an update on recent developments. First, we describe the physical barriers that must be overcome for AAV-delivered gene therapies to reach target cells in the CNS. We then put a spotlight on the natural AAV9 capsid's inherent propensity to cross the BBB and key lessons learned from its use for delivering a therapeutic payload for the treatment of spinal muscular atrophy. Next, we summarize methods for engineering recombinant AAV (rAAV) capsids with improved brain penetrance, and present in vitro paradigms for predicting their capacity to cross the human BBB. We also present strategies for side-stepping the delivery limitations of existing rAAV vectors. Finally, we point toward a few notable clinical studies whose outcomes may advance our understanding of what rAAV-delivered gene therapies can offer to people afflicted with CNS disorders.
    Keywords:  adeno-associated virus (AAV); capsid; gene therapy (GT); neurodegenerative diseases; neurological disease
    DOI:  https://doi.org/10.3389/fnins.2026.1768545
  24. Clin Toxicol (Phila). 2026 Mar 17. 1-14
       INTRODUCTION: Lamotrigine is prescribed for neurological and psychiatric conditions, including epilepsy and bipolar disorder. Although generally safe, it may cause rare but severe cutaneous adverse reactions, such as Stevens-Johnson syndrome. This review synthesized case reports and case series on lamotrigine-induced Stevens-Johnson syndrome to improve clinical awareness and promote safer prescribing.
    METHODS: PubMed was searched from inception to December 2024 using terms related to lamotrigine and Stevens-Johnson syndrome. Eligible studies were case reports or case series demonstrating Stevens-Johnson syndrome after lamotrigine use. Studies not reporting Stevens-Johnson syndrome, lacking clinical details, or not implicating lamotrigine were excluded. A total of 264 records were identified, and 36 studies met the inclusion criteria. Screening, quality assessment, and data extraction were done independently by two reviewers. Data on demographics, indications for use, lamotrigine dosage, co-administered drugs, clinical features, management, and patient outcomes were extracted and synthesized.
    RESULTS: Thirty-six studies comprising 38 individual cases were included. Lamotrigine was used either alone or in combination, most frequently with valproic acid (n = 19). Lamotrigine doses ranged from 12.5 to 750 mg/day, with most cases developing Stevens-Johnson syndrome within the first month of therapy. Clinical features included mucocutaneous lesions, epidermal detachment, and systemic symptoms such as fever and conjunctivitis. Management typically involved immediate lamotrigine discontinuation, corticosteroids, immunoglobulins, and supportive care. Most patients recovered within 2-3 weeks, although two deaths were reported.
    DISCUSSION: The findings show that the risk of lamotrigine-induced Stevens-Johnson syndrome is highest in the initial weeks of therapy, especially when lamotrigine is combined with valproic acid or titrated rapidly. Early warning signs such as fever and mucosal symptoms should be closely monitored to ensure timely intervention. Although corticosteroids and immunoglobulins are commonly used, their effectiveness remains uncertain, and supportive care continues to be the cornerstone of management.
    CONCLUSION: Lamotrigine-induced Stevens-Johnson syndrome is a rare but serious reaction. Careful dose titration, early recognition of symptoms, and patient education are imperative. Standardized reporting and causality assessment are needed to strengthen the evidence base and support safer prescribing.
    Keywords:  Lamotrigine; Stevens–Johnson syndrome; adverse drug reactions; cutaneous reactions; systematic review
    DOI:  https://doi.org/10.1080/15563650.2026.2634767
  25. Drug Discov Today. 2026 Mar 16. pii: S1359-6446(26)00049-8. [Epub ahead of print] 104644
      Neurodegenerative diseases (NDDs), such as Friedreich ataxia (FA) and multiple sclerosis (MS), are marked by progressive neurodegeneration and heterogeneous pathologies. Despite distinct aetiologies, FA and MS appear to share some overlapping molecular mechanisms, including iron and lipid dysregulation, mitochondrial dysfunction, oxidative stress, and neuroinflammation. Recent research, including comparative transcriptomic analyses, offers valuable insights into shared disease pathways, with implications for potential biomarkers and therapeutic targets. In this review, we explore the shared pathological features and disease mechanisms in FA and MS, highlighting how delineating these shared pathways could inform early diagnostic strategies and support the development of targeted, mechanism-based interventions, including opportunities for drug repurposing.
    Keywords:  Friedreich ataxia; drug repurposing; inflammation; mitochondrial dysfunction multiple sclerosis; oxidative stress; targeted therapy
    DOI:  https://doi.org/10.1016/j.drudis.2026.104644
  26. Biomed Pharmacother. 2026 Mar 17. pii: S0753-3322(26)00214-3. [Epub ahead of print]198 119181
      The advent of mRNA-based immunotherapeutics has fundamentally changed the nature of modern medicine. Although mRNA therapeutics initially developed to enhance vaccination platforms, they have rapidly expanded into gene editing and protein replacement applications. The rapid development and global deployment of mRNA vaccines during the COVID-19 pandemic emphasized the versatility and clinical potential of this modality and enabled swift progresses to infectious diseases and genetic disorders. mRNA work by exploiting the ability of the host cell system to produce desired proteins, however, clinical translation of mRNA immunotherapeutics remains constrained by challenges such as intrinsic instability, limited cellular uptake, inefficient endosomal escape, and suboptimal protein expression. Nanotechnology-based delivery systems have partially addressed these barriers over the past two decades and enabeled improved protection, targeting, and intracellular release. In this review, we conceptualize targeted mRNA delivery as a multistep process defined by Circulation-Internalization-Endosomal Escape-Expression (CIEE). We examine advances in systemic biodistribution control, organ-specific targeting, and precision delivery to antigen-presenting cells (APCs), and we discuss emerging strategies to optimize cytosolic transfection efficiency in immunotherapeutic applications. Advanced targeting strategies from organ-level biodistribution to cellular-level precision targeting of APCs are elucidated in details. From all the above, it follows that a solid knowledge in molecular biology, nanotechnology, and immunology is required for fine-tuned immunotherapeutic design. The current review attempt to serve as a reference to further advance optimizing targeted delivery of mRNA Immunotherapeutics.
    Keywords:  Immunotherapy; Nanotechnology; Targeted delivery; Vaccines; mRNA
    DOI:  https://doi.org/10.1016/j.biopha.2026.119181
  27. Eur J Health Law. 2026 Mar 17. 1-28
      In the EU rules on the right to reimbursement of cross-border healthcare, no specific or additional protection is provided to patients with rare diseases. This approach is inconsistent with other EU measures in the field of rare diseases, such as the Orphan Medicinal Products Regulation. This "gap" in legal protection should be filled by relying on the Charter of Fundamental Rights. The CJEU has developed a non-discrimination "frame" for cross-border healthcare cases in A v Veselības Ministrija, which should be applied to patients with rare diseases. This means that, to avoid discrimination on the ground of disability, additional protection mechanisms should be developed for patients with rare diseases in the procedure for requesting prior authorisation of cross-border medical treatment. Patients can rely on these mechanisms throughout the procedure for prior authorisation.
    DOI:  https://doi.org/10.1163/15718093-bja10159
  28. Int J Biol Macromol. 2026 Mar 17. pii: S0141-8130(26)01417-0. [Epub ahead of print] 151491
      The A30P point mutation in the α-synuclein (α-syn) protein is linked to a familial form of Parkinson's disease (PD), the most common motor neurodegenerative disorder. The association of α-syn with lipids in cellular membranes plays a key role in modulating the aggregation behavior of the protein, as well as its toxicity. Here, we studied the impact of the A30P mutation on the interaction of α-syn with mitochondrial membranes, since the interplay between α-syn aggregation and mitochondrial dysfunction is central for the pathogenic process in PD, but still not completely understood. Experiments using model vesicles with membranes enriched in the mitochondrial signature phospholipid cardiolipin (CL) demonstrated that these membranes markedly accelerate and promote the aggregation of A30P α-syn, with respect to the wild-type protein. In turn, A30P caused enhanced changes in membrane fluidity and permeabilization of CL-containing membranes. Moreover, utilizing single-channel planar bilayer measurements, A30P α-syn was shown to increase the membrane conductance in mito-mimetic bilayers, possibly by membrane thinning and incorporation of ion-conducting pores. The incubation of A30P α-syn with isolated mitochondria caused mitochondrial swelling, efflux of cytochrome c and lowered the mitochondrial membrane potential, all key indicators of mitochondrial membrane damage. Collectively, our results demonstrate that the A30P mutation aggravates the deleterious liaison between α-syn and CL-rich membranes, providing a mechanistic basis for mitochondrial dysfunction associated with this α-syn variant.
    Keywords:  Alpha-synuclein A30P; Cardiolipin; Mitochondria; Parkinson's disease; Protein aggregation; Protein-lipid interactions
    DOI:  https://doi.org/10.1016/j.ijbiomac.2026.151491
  29. Dtsch Arztebl Int. 2026 Apr 03. pii: arztebl.m2026.0030. [Epub ahead of print]123(7):
    members of the study group
       BACKGROUND: Genetic changes in the germline are the main cause of rare diseases (RD) and represent a significant disease burden in the population. Rapid and comprehensive genetic diagnosis is the key to clinical management.
    METHODS: Whole-genome sequencing was used to diagnose RD in a clinically heterogeneous patient cohort representative of real-world clinical practice. Three subgroups were distinguished based on genetic pre-diagnosis. 963 genomes were sequenced (360 index individuals from different families and 603 family members). The families received genetic counseling and were asked about their acceptance of the diagnostic test.
    RESULTS: The diagnosis rate in the overall cohort was 30% (95% confidence interval: [25.3; 34.7%]; 108/360). In 2.2% ([0.7; 3.7%]; 8/360) of cases, variants were found that would not have been detectable in the exome, corresponding to 7.4% ([2.4; 12.4%]; 8/108) among the detected cases in a direct comparison of "exome versus genome." The acceptance of genome sequencing was very high when embedded in human genetic counseling.
    CONCLUSION: Genome sequencing is an effective way to diagnose RD. Genome data provide a comprehensive basis for continuous re-evaluation and are superior to exome data in this respect. The integration of genome sequencing into standard care is now under evaluation as part of the nationwide "Model project genome sequencing" in Germany.
    DOI:  https://doi.org/10.3238/arztebl.m2026.0030
  30. IEEE Trans Med Imaging. 2026 Mar 17. PP
      Longitudinal brain analysis is essential for understanding healthy aging and identifying pathological deviations. Longitudinal registration of sequential brain MRI underpins such analyses. However, existing methods are limited by reliance on densely sampled time series, a trade-off between accuracy and temporal smoothness, and an inability to prospectively forecast future brain states. To overcome these challenges, we introduce TimeFlow, a learning-based framework for longitudinal brain MRI registration. TimeFlow uses a U-Net backbone with temporal conditioning to model neuroanatomy as a continuous function of age. Given only two scans from an individual, TimeFlow estimates accurate and temporally coherent deformation fields, enabling non-linear extrapolation to predict future brain states. This is achieved by our proposed inter-/extrapolation consistency constraints applied to both the deformation fields and deformed images. Remarkably, these constraints preserve temporal consistency and continuity without requiring explicit smoothness regularizers or densely sampled sequential data. Extensive experiments demonstrate that TimeFlow outperforms state-of-the-art methods in terms of both future timepoint forecasting and registration accuracy. Moreover, TimeFlow supports novel biological brain aging analyses by differentiating neurode-generative trajectories from normal aging without requiring segmentation, thereby eliminating the need for labor-intensive annotations and mitigating segmentation inconsistency. TimeFlow offers an accurate, data-efficient, and annotation-free framework for longitudinal analysis of brain aging and chronic diseases, capable of forecasting brain changes beyond the observed study period.
    DOI:  https://doi.org/10.1109/TMI.2026.3674458
  31. Curr Opin Biomed Eng. 2026 Jun;pii: 100658. [Epub ahead of print]38
      The eukaryotic epigenome plays a central role in regulating gene expression, cellular identity, and development through dynamic, multilayered biochemical modifications to DNA, histones, and chromatin architecture. Disruption of these regulatory mechanisms contributes to a wide range of human diseases, including cancer, neurodegenerative disorders, and immunological conditions. Targeted epigenome editing offers promising discovery and therapeutic strategies by enabling the correction of aberrant epigenetic states without the need for permanent changes to the DNA sequence. The catalytically inactive CRISPR-Cas (dCas) molecule fused to epigenetic effector domains has emerged as a versatile platform for programmable, locus-specific modulation of chromatin states. These CRISPR-based epigenetic editors can deposit or remove desired epigenetic marks and alter three-dimensional genome organization to fine-tune gene expression with high specificity. Recent developments have expanded the CRISPR epigenome editing toolbox by introducing new effector domains, improving multiplexing capabilities, and enabling large-scale genetic screening, leading to novel insights into the functional genomics across various cellular contexts. However, clinical translation remains challenged by inefficient delivery and suboptimal editing efficacy in vivo. This review highlights recent advances in CRISPR-based epigenetic editing, with a focus on applications in primary cells, new tool development, and the translational potential of epigenome modulation for safe, durable, and precise therapies.
    DOI:  https://doi.org/10.1016/j.cobme.2026.100658
  32. Evid Policy. 2026 Mar 19. 1-19
       Background: Knowledge mobilisation concerns translating knowledge into action and bridging the gap between knowledge production and its apt utilisation in practice. Scholars have called for more interactive models that integrate different forms of knowledge through iterative collaboration among diverse actors. However, insights on how such interactive models function in practice are scarce. This article addresses this gap by examining how knowledge is mobilised during implementation of the positive deviance (PD) approach, a problem-solving approach involving diverse actors.
    Methods: The article draws on an in-depth qualitative case study of a cross-sectoral project in six Norwegian municipalities, where PD was applied to address youth marginalisation. Data were generated through iterative PD processes involving practitioners, managers and stakeholders across sectors. Insights were gleaned on PD as an interactive strategy for knowledge mobilisation.
    Findings: The findings show that PD enabled the identification and amplification of locally embedded practices, facilitated cross-sector collaboration, and contributed to shifts in participants' understandings of problems and solutions. Rather than relying on external expert knowledge, PD supported practice-driven learning and adaptive responses, resulting in interventions being perceived as more context-sensitive and sustainable.
    Discussion and conclusions: The article argues that PD represents a promising strategy for interactive knowledge mobilisation by reconfiguring the relationship between evidence, policy and practice. It contributes to debates on co-creation and knowledge use by demonstrating how practice-based knowledge can act as a driver of change. Certain limitations related to institutional scalability are discussed. The findings have implications for research, policy and practice addressing complex social challenges.
    Keywords:  interactive knowledge mobilisation; positive deviance; public innovation; youth inclusion
    DOI:  https://doi.org/10.1332/17442648Y2026D000000086
  33. J Biopharm Stat. 2026 Mar 20. 1-12
      For rare disease drug development, a single-stage hypothesis testing procedure is often considered for clinical investigation regarding safety and efficacy of a test treatment study. Under the hypothesis testing framework, "p-value less than 0.05 with at least 80% power" is often used as the gold standard in the regulatory review/approval process. This regulatory standard, however, may not be feasible in rare disease drug development due to the small patient population available and the large variability associated with the clinical outcome. To overcome this controversial issue, alternatively, it is suggested that an innovative probability-based confidence interval approach based on precision analysis be considered. The proposed probability-based confidence interval approach can not only stay away from the limitations and concerns regarding the use of p-value but also provide valuable information regarding whether the observed results are reproducible.
    Keywords:  Hypotheses testing; p-value; probability monitoring procedure; probability-based confidence interval approach; regulatory flexibility; type I error rate
    DOI:  https://doi.org/10.1080/10543406.2026.2644301