bims-medebr Biomed News
on Metabolism of the developing brain
Issue of 2026–05–24
fifteen papers selected by
Regina F. Fernández, Johns Hopkins University



  1. Age Ageing. 2026 May 04. pii: afag136. [Epub ahead of print]55(5):
      
    Keywords:  ageing; brain; cerebral; delirium; metabolism
    DOI:  https://doi.org/10.1093/ageing/afag136
  2. J Transl Med. 2026 May 20.
       BACKGROUND: Cerebral glucose hypometabolism in Alzheimer's disease (AD) leads to enhanced metabolism of fatty acids (FAs) and branched-chain amino acids (BCAAs) as a compensatory mechanism. While there have been some 13C labeled studies investigating the metabolism of FAs and BCCAs, their clinical translation is challenging. In this study, we investigated the potential of measuring neurometabolic perturbations through macromolecular signal at 0.9 ppm (MM09) in proton magnetic resonance (1H MR) spectrum. This signal represents a composite macromolecular signal with contributions from lipids and BCAA associated methyl resonances and may be sensitive to metabolic alterations occurring during glucose hypometabolism in AD.
    METHODS: MM09 levels were measured from localized 1H MR spectra in the hippocampus and thalamus/hypothalamus of male and female APPNL-F/NL-F (AD) mice. In addition, the levels of glutamate in these regions were also recorded as it is known to be reduced under glucose hypometabolism in AD. We further studied the metabolic association of MM09 with glutamate in Pearson correlation plots. To find the statistical significance of difference two-way ANOVA analysis with post-hoc Tukey HSD tests were used.
    RESULTS: Male AD mice exhibited significantly reduced MM09 (15.42 ± 1.32 vs. 16.93 ± 1.15 mM; p = 0.008) and glutamate levels (15.27 ± 1.65 vs. 17.24 ± 1.21 mM; p = 0.004) in the hippocampus. Female AD mice did not show any changes in glutamate or MM09 levels. MM09 also showed a strong positive correlation with glutamate (R = 0.74; p < 0.0001).
    CONCLUSION: The observed reductions in MM09 and glutamate in male AD mice are consistent with neurometabolic alterations associated with impaired glucose metabolism, whereas the absence of such changes in female AD mice may reflect sex-specific metabolic resilience. The strong association between MM09 and glutamate suggests that MM09 may capture neurochemical changes linked to metabolic adaptations in AD. Because the MM09 resonance occurs in a relatively uncrowded region of the 1H MR spectrum, it may represent a promising spectroscopic marker for investigating metabolic shifts in AD and warrants further evaluation in clinical studies.
    Keywords:   1H MRS; Branched chain amino acids (BCAAs); Fatty acids (FAs); Glucose hypometabolism; Glutamate; Macromolecule 09 (MM09); Metabolism
    DOI:  https://doi.org/10.1186/s12967-026-08073-6
  3. Mol Neurodegener. 2026 May 21.
      Mitochondria transfer has emerged as a distinctive mechanism for intercellular communication and neuronal homeostasis. Neurones, owing to their unique bioenergetic demands, are particularly vulnerable to mitochondrial dysfunction, a shared pathogenetic feature across many neurological conditions, including neurodegenerative disorders, cerebrovascular diseases, and brain injuries. Intercellular transfer of mitochondria represents a potential adaptive mechanism rectifying compromised mitochondrial function. Neuroglial cells, especially astrocytes and microglia, frequently act as mitochondrial donors, supplying functional mitochondria to stressed neurones to restore bioenergetic capacity and influence disease trajectories. However, mitochondria transfer is intrinsically context dependent and can exert opposing effects. In addition to providing metabolic support, damaged mitochondria may also be transferred, propagating pathological signals, and exacerbating tissue injury. Moreover, in advanced disease states, mitochondrial malfunction often affects all cell types in the nervous system, including neuroglia, limiting the availability of healthy endogenous mitochondrial donors. This review critically examines mitochondria transfer in neurological diseases, with a focus on glial contribution and underlying mechanisms, and outlines key challenges and opportunities for advancing both mechanistic understanding and therapeutic translation.
    Keywords:  Ageing; Extracellular vesicles; Mitochondrial transplantation; Neurodegeneration; Neuroglia; Traumatic brain injury; Tunnelling nanotubes
    DOI:  https://doi.org/10.1186/s13024-026-00953-1
  4. ACS Chem Neurosci. 2026 May 19.
      This study employed Fourier Transform Infrared (FTIR) and Raman microspectroscopy to investigate the long-term biochemical effects of prenatal exposure to a ketogenic diet (KD) on the developing rat brain. KD, high in fat and low in carbohydrates, shifts metabolism from glucose to ketone utilization and is widely used to treat drug-resistant epilepsy. Given its potential use in pregnant women, understanding KD impact on offspring neurodevelopment is critically important. By combining the complementary strengths of FTIR and Raman microspectroscopy, this study enabled the detection of subtle biochemical changes within brain tissue of animals fed prenatally with KD. Spectroscopic analyses revealed region- and sex-dependent alterations, primarily involving metabolism of lipids and phosphate-containing compounds─key components of myelin and cellular membranes. Most changes were observed in 60-day-old males prenatally exposed to KD. Creatine- and cholesterol-rich inclusions were detected in hippocampal and cortical regions, possibly reflecting maladaptive outcomes of altered energy metabolism and/or neuroadaptive mechanisms related to metabolic preconditioning. Furthermore, these males exhibited reductions in multiple lipid-associated FTIR parameters, which potentially reflecting disruptions in oligodendrocyte function or myelination dynamics. While 30-day-old females from experimental group showed region-specific lipid decreases and elevated phosphate-related ratios, these changes largely normalized by 60 days, indicating developmental stabilization of metabolic effects after prenatal KD exposure. In contrast to males, females showed no creatine or cholesterol inclusions, likely reflecting sex-specific modulation. Estrogens regulate creatine metabolism, support mitochondrial and antioxidant function, and modulate lipid homeostasis, providing neuroprotection and mitigating metabolic disturbances.
    Keywords:  FTIR microspectroscopy; Raman spectroscopy; biochemical analysis; creatine and cholesterol inclusions; ketogenic diet; prenatal exposure
    DOI:  https://doi.org/10.1021/acschemneuro.6c00111
  5. iScience. 2026 May 15. 29(5): 115638
      Metabolic dysregulation is a key feature of Alzheimer's disease (AD) pathogenesis, with the APOE ε4 variant (APOE4) representing the strongest genetic risk factor. In this study, we utilized a metabolite-centric approach to investigate how APOE4 reshapes cellular metabolism across brain cell types. Transcriptomic data from isogenic iPSC-derived neurons, astrocytes, and microglia were integrated into a human genome-scale metabolic model to identify genotype-specific alterations. These findings were validated using metabolomics data from the same cell types. In addition to cholesterol and fatty acid dysregulation, we identified alterations in bile acid biosynthesis, folate metabolism, and thyroid hormone metabolism. Similar metabolic signatures were also detected in human postmortem transcriptomic data. Integrating transcriptomic and metabolomic data enhances the understanding of biological mechanisms underlying APOE4-associated metabolic dysregulation in AD.
    Keywords:  Omics; Systems biology
    DOI:  https://doi.org/10.1016/j.isci.2026.115638
  6. Free Radic Biol Med. 2026 May 19. pii: S0891-5849(26)00763-X. [Epub ahead of print]252 559-579
      Neurodegenerative diseases are increasingly recognized as disorders associated with metabolic dysfunction with arginine metabolism emerging as a significant contributor. Arginase, by regulating the balance between arginine and ornithine, is positioned at the crossroads of multiple arginine metabolic pathways, thereby controlling a variety of cellular processes essential for proper brain homeostasis. Chronic disruption of these pathways may lead to dysfunction of neurons and glia ultimately resulting in the induction of neurodegenerative processes. In this review, based on data from patients and experimental models, we synthesize and critically evaluate evidence demonstrating alterations in arginase isoenzymes and associated metabolic pathways in Alzheimer's Parkinson's and Huntington's diseases, and amyotrophic lateral sclerosis. We discuss mechanisms through which dysregulation of arginase and arginine metabolism may contribute to neurodegeneration, including disturbances in nitrogen metabolism, oxidative and nitrosative stress, mitochondrial dysfunction, and neuroinflammation. Based on this body of evidence, we propose therapeutic strategies targeting arginase-related pathways, with the aim of preserving cellular metabolic homeostasis to ameliorate disease progression. Finally, we outline directions for future research, emphasizing that a proper understanding of the physiological roles of arginase isoenzymes and their disease-, stage-, and cell-specific dysregulation will be essential for the development of effective metabolically targeted therapies against neurodegenerative diseases.
    Keywords:  Alzheimer's disease; Ammonia; Amyotrophic lateral sclerosis; Arginase; Arginine; Huntington's disease; Neurodegeneration; Nitric oxide; Parkinson's disease; Polyamines; Urea
    DOI:  https://doi.org/10.1016/j.freeradbiomed.2026.05.285
  7. Cell Death Differ. 2026 May 22.
      Parkinson's disease (PD) is a progressive neurodegenerative disease. Current treatment strategies for PD mainly focus on dopamine replacement and regulation of dopaminergic signaling. Here, we reveal the unique role of the astrocytic dopamine D2 (Drd2) receptor in regulating mitochondrial function, thereby improving Parkinson's disease-like symptoms in a mouse model. Transcriptome sequencing and metabolomics suggest that deletion of astrocytic Drd2 receptor significantly aggravates mitochondrial dysfunction. Mechanistically, we demonstrate that the Drd2 receptor regulates mitochondrial complex I activity by recruiting the scaffold protein β-arrestin2, which facilitates its interaction with NDUFA4 and NDUFA10, two subunits of mitochondrial complex I. Notably, the neuroprotective effect of Drd2 activation in vivo was completely abolished upon selective knockdown of NDUFA10 in mouse astrocytes. The identification of this novel mechanistic axis not only elucidates how astrocytes maintain neuronal mitochondrial homeostasis via dopaminergic signaling but also establishes a transformative framework for the development of targeted combination therapies that concurrently address mitochondrial dysfunction and dopamine receptor dysregulation as a promising avenue for advancing PD treatment strategies.
    DOI:  https://doi.org/10.1038/s41418-026-01756-z
  8. Nat Commun. 2026 May 20.
      The brain is highly enriched in poly-unsaturated fatty acids (PUFAs) and their deficiency has been associated with several neuropsychiatric disorders. Here, we demonstrate that the Dopamine receptor D2 (D2R), a class A G protein coupled receptor (GPCR) which is a main target of antipsychotics, displays specific sensitivity to membrane PUFA composition. We found that membrane enrichment with either of two distinct PUFAs significantly impairs agonist-induced D2R endocytosis in HEK-293 cells and cortical neurons. This treatment does not affect clathrin-mediated endocytosis or the internalization of several other GPCRs. Moreover, we show that D2R clustering at endocytic pits is not affected, but that recruitment of β-arrestin2 is strongly impaired and endocytic vesicle formation is slowed down. Finally, mutation of key residues in intracellular loop 2 abolishes the sensitivity of D2R endocytosis to PUFA enrichment. We conclude that D2R trafficking is specifically dependent on membrane PUFAs, which could influence its role in the control of brain function and behavior.
    DOI:  https://doi.org/10.1038/s41467-026-73057-5
  9. J Neurochem. 2026 May;170(5): e70475
      The microbiota-gut-brain-axis is a bidirectional communication system between the trillions of microbes in the gastrointestinal tract and the brain. This axis influences brain processes like learning and memory, but the underlying mechanisms aren't fully understood. Microbial metabolites, particularly short-chain fatty acids (SCFAs) from dietary fibre fermentation, are considered key mediators. We investigated the effects of the three most abundant SCFAs, acetate, butyrate, and propionate, on ex vivo hippocampal slice electrophysiology to explore potential sex-specific mechanisms. We used physiologically relevant concentrations to ensure translational relevance. Our findings show that a 40-min exposure to 3 μM butyrate enhanced long-term potentiation (LTP) in both male and female mice. Butyrate's effects were mediated by the free fatty acid receptor 3 (FFAR3), as its inhibition with β-Hydroxybutyrate (BHB) abolished the enhanced potentiation in slices from female mice, but not males. BHB alone had no effect on LTP in either sex. To understand this dimorphism, we examined messenger ribonucleic acid (mRNA) expression of FFARs and SCFA transporters in cornu ammonis 1 (CA1) hippocampal tissue but found no explanatory differences. Acetate and propionate had no significant effect on LTP, basic synaptic efficacy, or short-term plasticity. In conclusion, our study provides novel insights into the sex-specific modulation of hippocampal synaptic plasticity by butyrate. Our data suggest that FFAR3 activation is crucial for these effects in females, highlighting the gut microbiota's potential to shape hippocampal function. Further studies are warranted to investigate the behavioural consequences of enhanced hippocampal butyrate and to fully parse the mechanisms behind the sex differences we observed.
    DOI:  https://doi.org/10.1111/jnc.70475
  10. Front Hum Neurosci. 2026 ;20 1768774
      Aging is a complex biological process characterized by progressive functional decline and increased vulnerability to age-related diseases, particularly neurodegenerative disorders. At the biological level, aging is characterized by a range of molecular and cellular mechanisms, including genomic instability, telomere attrition, loss of proteostasis, mitochondrial dysfunction, and chronic inflammation, which collectively contribute to cognitive decline and neuronal dysfunction over time. These hallmarks do not function independently but instead interact with one another during aging and neurodegeneration. Consequently, brain aging and neurodegenerative diseases are recognized as closely interconnected processes. To better understand this relationship, it is essential to examine the shared molecular and cellular mechanisms that link brain aging to neurodegeneration. In this review, we summarize the principal mechanisms underlying aging and neurodegenerative diseases, examine their roles in these processes, and highlight how their interactions shape both aging and neurodegeneration. We also discuss potential therapeutic strategies targeting key mechanisms involved in aging and neurodegeneration.
    Keywords:  brain aging; genomic instability; inflammation; loss of proteostasis; mitochondrial dysfunction; neurodegenerative diseases; telomere attrition; therapeutic strategies
    DOI:  https://doi.org/10.3389/fnhum.2026.1768774
  11. Exp Neurol. 2026 May 20. pii: S0014-4886(26)00204-9. [Epub ahead of print]403 115840
      Secondary injury cascades following spinal cord injury (SCI) are closely associated with local metabolic dysregulation and persistent neuroinflammation. However, the spatiotemporal patterns of alterations centered on sphingolipid metabolism within the injury microenvironment, as well as their specific regulatory mechanisms in relation to neuroimmune inflammation, remain poorly understood at a systematic level. In this study, we integrated high-throughput lipidomics, spatial transcriptomics, and single-cell RNA sequencing (scRNA-seq) of multiple SCI models, to systematically construct a multidimensional spatiotemporal atlas of sphingolipid metabolism following injury. Lipidomics analysis revealed remodeling of sphingolipid metabolism, characterized by the progressive accumulation of neurotoxic sphingolipid metabolites and the depletion of myelin-associated lipids. Spatial transcriptomics demonstrated that regions of sphingolipid metabolism were strikingly confined to the 'inflammatory infiltration core' and the 'scar interface'. At the single-cell level, microglia were identified as the central cellular mediators of this metabolic reprogramming. Notably, we discovered a distinct microglial subpopulation characterized by high expression of the peroxisomal enzyme Hsd17b4 and the disease-associated marker Spp1, termed the 'high-sphingolipid metabolism' subtype. Pseudotime trajectory analysis indicated that sustained elevation of sphingolipid metabolic activity constitutes a potential determinant that prevents microglia from returning to homeostasis and drives their maladaptive polarization toward a chronic pathological phenotype. Immunofluorescence staining confirmed the specific enrichment of Hsd17b4+/Spp1+ microglia within the injury core. Our findings demonstrate that sphingolipid metabolism reprogramming in microglia represents a key mechanistic step in the propagation of secondary injury following SCI. These results provide novel theoretical foundations and potential therapeutic targets for modulating the immuno-metabolic microenvironment to promote functional recovery after spinal cord injury.
    Keywords:  Hsd17b4; Immunometabolism; Microglia; Secondary injury; Spatial transcriptomics; Sphingolipid metabolism; Spinal cord injury; Spp1
    DOI:  https://doi.org/10.1016/j.expneurol.2026.115840
  12. Exp Gerontol. 2026 May 20. pii: S0531-5565(26)00155-5. [Epub ahead of print] 113176
      Stroke is a major cause of death and permanent disability, which is described by abrupt loss of neuronal energy, oxidative injury, inflammation, and apoptosis, primarily mediated by mitochondrial dysfunction. Mitochondria are key regulators of stress responses, apoptosis, redox homeostasis, immune signaling and known as central signaling hubs, integrating pathways from multiple cellular compartments to maintain homeostasis. Among the major regulatory elements are protein kinase enzymes that modulate cell signaling by phosphorylating substrates. Several kinases, including members of the Akt, PKA, PKC, GSK-3β, PINK1, and MAPK families, dynamically translocate to mitochondria under physiological and pathological conditions. Once localized, they influence mitochondrial dynamics, bioenergetics, reactive oxygen species (ROS) production, and programmed cell death. Dysregulation of these functions has been implicated in impaired mitophagy, aberrant calcium signaling, and processes associated with the pathogenesis of various neurological disorders, particularly in those with acute brain injuries, such as acute ischemic stroke (AIS). Especially, mitochondrial kinase oxidative stress hallmarks of neuronal injury. In this review, we examine the role of mitochondrial-associated kinases in AIS, explore mechanisms of their translocation, downstream signaling effects, and their promise as druggable targets highlighting the importance of spatial dynamics of kinases and the need for precision therapies. Understanding these mechanisms may open new avenues for therapeutic intervention in neurological diseases with a focus on acute brain injury, by targeting mitochondrial signaling networks.
    Keywords:  Ischemia–reperfusion injury; Ischemic stroke; Mitochondria; Mitochondrial dysfunction; Neuroprotection; Protein kinase
    DOI:  https://doi.org/10.1016/j.exger.2026.113176
  13. Neurosci Appl. 2026 ;5 107005
      The canonical Wnt signaling pathway plays a key role in neurodevelopment and in maintaining cellular homeostasis of the central nervous system in adulthood. It regulates essential processes, such as cell proliferation, differentiation, and synaptogenesis. In vivo and genetic evidence suggests an association between attention-deficit/hyperactivity disorder (ADHD) and abnormalities in the Wnt pathway. Prior research from our group indicated heightened basal Wnt activity in neural stem cells (NSCs) derived from induced pluripotent stem cells (iPSCs) of pediatric ADHD patients and showed that methylphenidate (MPH) and omega-3 polyunsaturated fatty acids (ω-3 PUFAs) can modulate this pathway. While MPH is a first-line treatment for ADHD, ω-3 PUFAs are under investigation as a potential non-pharmacological supplement. Using the same functionality-based reporter technology, we assessed Wnt activity in iPSC-derived NSCs from 5 adult ADHD patients and 5 healthy controls. We examined whether ω-3 fatty acids (EPA and DHA), alone or combined, and DHA with MPH can modulate Wnt activity in these NSCs. Basal Wnt responsiveness did not differ between adult ADHD and control lines, although genetic risk for ADHD was associated with increased Wnt activity. EPA showed no statistically significant effects, while DHA strongly increased Wnt activity in both groups. DHA combined with EPA increased Wnt activity in ADHD lines, whereas DHA with MPH caused group-specific responses: enhancing Wnt signaling in ADHD but reducing it in controls. Compared to NSCs derived from children, adult-derived NSCs behave differently and show distinct responses to EPA and DHA, suggesting a potential route toward refined therapeutic strategies for adults.
    Keywords:  Attention-deficit/hyperactivity disorder; Docosahexaenoic acid; Methylphenidate; Neural stem cells; Omega-3; Wnt signaling
    DOI:  https://doi.org/10.1016/j.nsa.2026.107005
  14. Mol Cell Biochem. 2026 May 21.
      Mitochondrial pyruvate carrier (MPC) inhibition was found protective in models of neurodegenerative diseases, such as Alzheimer's and Parkinson's. However, little is known about MPC as a potential therapeutic target in Huntington's disease (HD), a neurodegenerative disorder with dysregulation of the pro-survival pathway integrated stress response (ISR). Here, we investigate if MPC inhibition modulates the ISR and mitigates mutant huntingtin (mut-Htt) proteotoxicity in a cellular HD model. We treated cells expressing N-terminal fragments of wild-type- (wt-) or mut-Htt with two MPC inhibitors (mitoglitazone and UK5099) or solvent control. Metabolism was assessed analysing resazurin reduction, oxygen consumption, extracellular acidification, and ATP levels. ISR activation and huntingtin proteostasis were assessed using western-blot and filter-trap assays. Mut-Htt-expressing cells showed decreased resazurin reduction and ATP levels, and increased eIF2α phosphorylation, indicating metabolic stress and ISR activation. MPC inhibitors (100 µM) increased resazurin reduction and decreased respiration. The latter was rescued by the membrane-permeant methyl pyruvate, which bypasses MPC inhibition. In wt-Htt-expressing cells, MPC inhibitors increased levels of ATP and ISR markers, suggesting metabolic adaptation and ISR activation. In mut-Htt-expressing cells, MPC inhibitors preserved ATP levels and attenuated mut-Htt-induced eIF2α phosphorylation but without changing soluble or aggregated mut-Htt levels. This work showed that MPC inhibition differentially modulates the ISR: it activates ISR in control cells and attenuates overactive ISR in mut-Htt-expressing cells. However, MPC inhibition did not impact the proteostasis of N-terminal fragment mut-Htt. Further studies are essential to explore MPC inhibition in less severe full-length mut-Htt-expressing models to better understand its therapeutic potential in HD.
    Keywords:  Aggregation; Huntingtin; Huntington’s disease; Integrated stress response; Metabolism; Mitochondrial pyruvate carrier
    DOI:  https://doi.org/10.1007/s11010-026-05573-3
  15. BMC Med Genomics. 2026 May 16.
       BACKGROUND: Long-chain fatty acid oxidation disorders (LC-FAOD) are inherited metabolic conditions caused by impaired mitochondrial β-oxidation of long-chain fatty acids, leading to rhabdomyolysis, cardiomyopathy, and hypoglycemia. Triheptanoin, a medium odd-chain triglyceride, provides anaplerotic substrates that replenish tricarboxylic acid cycle intermediates, offering alternative energy sources and potential therapeutic benefit.
    METHODS: This open-label, single-center phase II study evaluated the safety and efficacy of triheptanoin in 10 Korean patients with genetically confirmed LC-FAOD who experienced recurrent rhabdomyolysis despite conventional treatment. Triheptanoin was titrated to 35% of total daily caloric intake, and all patients completed 3 years of treatment. The primary outcome was safety, assessed by adverse events. Secondary outcomes included changes in the major clinical event (MCE) rate and duration, functional capacity, health-related quality of life (HRQoL), and organ function.
    RESULTS: The mean study duration was 3.5 ± 0.3 years. Serious adverse events occurred in nine patients (90%), most commonly rhabdomyolysis (100%), and were considered unrelated to triheptanoin. Mild gastrointestinal symptoms during titration were the most frequent treatment-related adverse events (80%). The median annualized MCE rate and duration decreased by 42.4% and 43.6%, respectively (P = 0.114 and P = 0.059). The duration per MCE was significantly reduced by 3.5 days, as assessed by a linear mixed-effects model (P = 0.022), with a significant reduction observed in the child subgroup (P < 0.001). In eight patients, the 12-minute walk test distance increased by 12.4% at 6 months and was maintained over 3 years (P = 0.385). HRQoL improved to within the normative range in adults, whereas child self-reported and parent proxy-reported scores showed an initial increase but remained suboptimal at 3 years. Progressive neuropathy and newly developed retinopathy and attention-deficit/hyperactivity disorder were observed during treatment.
    CONCLUSION: Triheptanoin significantly reduced hospitalization burden in Korean patients with LC-FAOD and was well-tolerated, with potential benefits in physical function.
    TRIAL REGISTRATION: Clinical Research Information Service (CRIS), Republic of Korea, KCT0006756, 15 November 2021.
    Keywords:  Energy metabolism disorders; Fatty acid oxidation disorders; Mitochondrial trifunctional protein; Triheptanoin; Very long-chain acyl-CoA dehydrogenase
    DOI:  https://doi.org/10.1186/s12920-026-02390-x