bims-mignad Biomed News
on Mitochondria galactose NAD
Issue of 2025–04–27
six papers selected by
Melisa Emel Ermert, Amsterdam UMC
  1. Mitochondrial NADPH fuels mitochondrial fatty acid synthesis and lipoylation to power oxidative metabolism.
  2. NMN reverses D-galactose-induced neurodegeneration and enhances the intestinal barrier of mice by activating the Sirt1 pathway.
  3. Analysis of the High-Order Conformational Changes in Glyceraldehyde-3-phosphate Dehydrogenase Induced by Nicotinamide Adenine Dinucleotide, Adenosine Triphosphate, and Oxidants.
  4. Neuroprotection by Mitochondrial NAD Against Glutamate-Induced Excitotoxicity.
  5. Sarcosine sensitizes lung adenocarcinoma to chemotherapy by dual activation of ferroptosis via PDK4/PDHA1 signaling and NMDAR-mediated iron export.
  6. Evolution, Possibilities, and Prospects for Application of the Methods of Assessment of Pyridine Nucleotides Pool for Studying Mechanisms of Brain Plasticity in Normal and Pathological Conditions.
  1. Nat Cell Biol. 2025 Apr 21.
    Mitochondrial NADPH fuels mitochondrial fatty acid synthesis and lipoylation to power oxidative metabolism.
    Dohun Kim, Rushendhiran Kesavan, Kevin Ryu, Trishna Dey, Austin Marckx, Cameron Menezes, Prakash P Praharaj, Stewart Morley, Bookyong Ko, Mona H Soflaee, Harrison J Tom, Harrison Brown, Hieu S Vu, Shih-Chia Tso, Chad A Brautigam, Andrew Lemoff, Marcel Mettlen, Prashant Mishra, Feng Cai, Doug K Allen, Gerta Hoxhaj.
      Nicotinamide adenine dinucleotide phosphate (NADPH) is a vital electron donor essential for macromolecular biosynthesis and protection against oxidative stress. Although NADPH is compartmentalized within the cytosol and mitochondria, the specific functions of mitochondrial NADPH remain largely unexplored. Here we demonstrate that NAD+ kinase 2 (NADK2), the principal enzyme responsible for mitochondrial NADPH production, is critical for maintaining protein lipoylation, a conserved lipid modification necessary for the optimal activity of multiple mitochondrial enzyme complexes, including the pyruvate dehydrogenase complex. The mitochondrial fatty acid synthesis (mtFAS) pathway utilizes NADPH for generating protein-bound acyl groups, including lipoic acid. By developing a mass-spectrometry-based method to assess mammalian mtFAS, we reveal that NADK2 is crucial for mtFAS activity. NADK2 deficiency impairs mtFAS-associated processes, leading to reduced cellular respiration and mitochondrial translation. Our findings support a model in which mitochondrial NADPH fuels the mtFAS pathway, thereby sustaining protein lipoylation and mitochondrial oxidative metabolism.
    DOI:  https://doi.org/10.1038/s41556-025-01655-4
  2. Front Pharmacol. 2025 ;16 1545585
    NMN reverses D-galactose-induced neurodegeneration and enhances the intestinal barrier of mice by activating the Sirt1 pathway.
    Yuxian Lin, Yajing Wang, Xinxin Yang, Ziwei Ding, Mingye Hu, Xianfeng Huang, Qichun Zhang, Yingcong Yu.
       Background: Age-related decline in nicotinamide adenine dinucleotide (NAD+)-a central regulator of cellular metabolism, DNA repair, and immune homeostasis-is strongly associated with physiological dysfunction. Nicotinamide mononucleotide (NMN), a potent NAD+ precursor, shows promise in counteracting aging-related pathologies, particularly neurodegenerative decline.
    Methods: An aging model was established in mice through 8-week D-galactose (D-gal) exposure, followed by NMN oral supplementation. Behavioral outcomes (open field test, Morris water maze) were analyzed alongside oxidative stress markers (SOD, CAT, AGEs), inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-10), and neurotransmitters (LC-MS/MS). Apoptotic activity (TUNEL, p16/p21), mitochondrial regulators (Sirt1, p-AMPK, PGC-1α), and intestinal barrier integrity (HE/AB-PAS staining) were evaluated. Sirt1 dependency was confirmed using inhibitor Ex527.
    Results: NMN restored locomotor activity and spatial memory in D-gal mice without altering body weight. Mechanistically, NMN synergistically attenuated oxidative stress and systemic inflammation, elevating antioxidant enzymes (SOD, CAT) and IL-10 while suppressing pro-inflammatory cytokines (TNF-α, IL-6) and AGEs. Cortical/hippocampal analyses revealed reduced apoptosis (TUNEL+ cells) and senescence markers (p16, p21), with enhanced mitochondrial function via Sirt1/AMPK/PGC-1α activation (Sirt1, p-AMPK). NMN concurrently preserved intestinal mucosal architecture, mitigating D-gal-induced barrier disruption. Crucially, all benefits were abolished by Sirt1 inhibition, confirming pathway specificity.
    Conclusion: Our findings establish NMN as a multifaceted therapeutic agent that preserves neurocognitive function and intestinal homeostasis in aging models by orchestrating antioxidative, anti-inflammatory, and antiapoptotic responses through Sirt1/AMPK/PGC-1α activation. This work provides translational insights into NAD+-boosting strategies for age-related disorders.
    Keywords:  NMN; SIRT1; aging; intestinal barrier; neuroinflammation; oxidative stress
    DOI:  https://doi.org/10.3389/fphar.2025.1545585
  3. Biochemistry. 2025 Apr 21.
    Analysis of the High-Order Conformational Changes in Glyceraldehyde-3-phosphate Dehydrogenase Induced by Nicotinamide Adenine Dinucleotide, Adenosine Triphosphate, and Oxidants.
    Himari Suzuki, Yuki Nicole Makiyama, Yuta Watanabe, Hideo Akutsu, Michiko Tajiri, Yoko Motoda, Ken-Ichi Akagi, Tsuyoshi Konuma, Satoko Akashi, Takahisa Ikegami.
      Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a key enzyme in glycolysis. Beyond this normal function, GAPDH acts as a moonlighting protein, interacting with nonglycolytic molecules to fulfill additional roles, such as apoptosis induction. However, the three-dimensional (3D) structural details underlying these interactions remain unclear, likely due to their dynamic and transient nature. To address this issue, we investigated the structural properties of human and porcine GAPDH using a combination of biophysical techniques, including nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry, gel filtration chromatography, and thermal shift assays, with a particular focus on their 3D structures. Our results revealed that although GAPDH becomes unstable upon nicotinamide adenine dinucleotide (NAD+) depletion (apo state), its oligomeric structure as a tetramer remains preserved regardless of temperature. In contrast, the presence of adenosine triphosphate (ATP) promotes dimerization at low temperatures, as previously reported. Furthermore, our NMR data suggest that ATP binding exposes the dimer interface and increases the flexibility of side chains in this region. These findings indicate that GAPDH maintains a stable tetrameric structure in the presence of NAD+ but becomes structurally unstable and likely more susceptible to oxidation upon NAD+ depletion. Additionally, our analyses showed that partial nitrosylation of GAPDH subunits does not induce significant tertiary structural changes. However, significant structural alterations were observed when all four subunits were nitrosylated, although the possibility remains that residues other than the active site residue, Cys152, may have been oxidized. We propose that NAD+ depletion, along with oxidation or nitrosylation─most likely at Cys152─destabilizes the GAPDH conformation, and that subsequent ATP binding promotes dimerization. This subunit dissociation may serve as a structural basis for GAPDH's interactions with other molecules and its moonlighting functions.
    DOI:  https://doi.org/10.1021/acs.biochem.4c00794
  4. Cells. 2025 Apr 12. pii: 582. [Epub ahead of print]14(8):
    Neuroprotection by Mitochondrial NAD Against Glutamate-Induced Excitotoxicity.
    Bruna S Paiva, Diogo Neves, Diogo Tomé, Filipa J Costa, Inês C Bruno, Diogo Trigo, Raquel M Silva, Ramiro D Almeida.
      Excitotoxicity is a pathological process that occurs in many neurological diseases, such as stroke or epilepsy, and is characterized by the extracellular accumulation of high concentrations of glutamate or other excitatory amino acids (EAAs). Nicotinamide adenine dinucleotide (NAD) depletion is an early event following excitotoxicity in many in vitro and in vivo excitotoxic-related models and contributes to the deregulation of energy homeostasis. However, the interplay between glutamate excitotoxicity and the NAD biosynthetic pathway is not fully understood. To address this question, we used a primary culture of rat cortical neurons and found that an excitotoxic glutamate insult alters the expression of the NAD biosynthetic enzymes. Additionally, using a fluorescent NAD mitochondrial sensor, we observed that glutamate induces a significant decrease in the mitochondrial NAD pool, which was reversed when exogenous NAD was added. We also show that exogenous NAD protects against the glutamate-induced decrease in mitochondrial membrane potential (MMP). Glutamate excitotoxicity changed mitochondrial retrograde transport in neurites, which seems to be reversed by NAD addition. Finally, we show that NAD and NAD precursors protect against glutamate-induced cell death. Together, our results demonstrate that glutamate-induced excitotoxicity acts by compromising the NAD biosynthetic pathway, particularly in the mitochondria. These results also uncover a potential role for mitochondrial NAD as a tool for central nervous system (CNS) regenerative therapies.
    Keywords:  NAD metabolism; excitotoxicity; glutamate; mitochondria
    DOI:  https://doi.org/10.3390/cells14080582
  5. Exp Hematol Oncol. 2025 Apr 24. 14(1): 60
    Sarcosine sensitizes lung adenocarcinoma to chemotherapy by dual activation of ferroptosis via PDK4/PDHA1 signaling and NMDAR-mediated iron export.
    Guangyao Shan, Yunyi Bian, Shencheng Ren, Zhengyang Hu, Binyang Pan, Dejun Zeng, Zhaolin Zheng, Hong Fan, Guoshu Bi, Guangyu Yao, Cheng Zhan.
       BACKGROUND: Ferroptosis, a regulated cell death driven by iron-dependent lipid peroxidation, is associated with chemoresistance in lung adenocarcinoma (LUAD). This study aims to investigate the role of sarcosine in ferroptosis and its underlying mechanisms.
    METHODS: An RSL3-induced ferroptosis model was used to screen a library of 889 human endogenous metabolites and metabolomic profiling was harnessed to identify metabolites associated with ferroptosis. Cell viability, lipid-reactive oxygen species (ROS), ferrous iron, malondialdehyde (MDA), and mitochondrial integrity were assessed to evaluate sarcosine's effects on ferroptosis. Metabolic fate was studied using 15N-labeled sarcosine. Next, we used untargeted metabolomic profiling and next-generation sequencing to dissect metabolic and transcriptomic changes upon sarcosine supplementation. The effects of sarcosine on ferroptosis and chemotherapy were further validated in patient-derived organoids (PDOs), xenograft models, and LUAD tissues.
    RESULTS: Sarcosine emerged as a potent ferroptosis inducer in the metabolic library screening, which was further confirmed via cell viability, lipid-ROS, ferrous iron, and MDA measurements. Metabolic flux analysis showed limited conversion of sarcosine to other metabolites in LUAD cells, while untargeted metabolomic profiling and seahorse assays indicated a metabolic shift from glycolysis to oxidative phosphorylation. Sarcosine enhanced pyruvate dehydrogenase activity to generate more ROS by interacting with PDK4, reducing PDHA1 phosphorylation. As a co-activator of N-methyl-D-aspartate receptor (NMDAR), sarcosine also exerted its pro-ferroptosis effect via regulating ferrous export through the NMDAR/MXD3/SLC40A1 axis. Given the significance of ferroptosis in chemotherapy, we validated that sarcosine enhanced the sensitization of cisplatin by promoting ferroptosis in LUAD cells, PDOs, and xenograft models.
    CONCLUSION: Sarcosine promotes ferroptosis and enhances chemosensitivity, suggesting its potential as a therapeutic agent in treating LUAD.
    Keywords:  Chemotherapy; Ferroptosis; Lung adenocarcinoma; Organoids; Sarcosine
    DOI:  https://doi.org/10.1186/s40164-025-00657-0
  6. Biochemistry (Mosc). 2025 Feb;90(2): 231-246
    Evolution, Possibilities, and Prospects for Application of the Methods of Assessment of Pyridine Nucleotides Pool for Studying Mechanisms of Brain Plasticity in Normal and Pathological Conditions.
    Anna V Zubova, Alexander A Groshkov, Arsenii K Berdnikov, Svetlana V Novikova, Natalia A Rozanova, Lyudmila V Nikolaeva, Vladimir V Salmin, Nataliya A Kolotyeva, Leonid G Khaspekov, Alla B Salmina, Stanislav O Yurchenko, Sergey N Illarioshkin.
      Nicotinamide adenine dinucleotide and its derivatives - NAD+, NADP+, NADH, NADPH - play an important role in cell metabolism, act as substrates or cofactors for a large number of enzymes involved in the DNA regulation of replication and repair, maintenance of calcium homeostasis in cells, biosynthetic processes, and energy production mechanisms. Changes in the ratio of oxidized and reduced forms of pyridine nucleotides accompanies development of oxidative and reductive stress that significantly contribute to the cell damage and induction of adaptive responses. Currently, a huge number of protocols aimed at quantitative or qualitative assessment of the pyridine nucleotide pool are in use, but all of them have their limitations associated with sample preparation processes, difficulties in the metabolite spectrum assessment, and complexity of data interpretation. Measuring pyridine nucleotide levels is relevant in the studies of pathophysiological regulatory mechanisms of the cell functional activity and intercellular communication. This is of particular relevance when studying the mechanisms of plasticity of the central nervous system in health and disease, since significant changes in the pools of pyridine nucleotides in cells are evident in neurodevelopmental disorders, neurodegeneration, and aging. Simple and reliable non-invasive methods for measuring levels of NAD+ and NADH are necessary to assess the brain cells metabolism with diagnostic and research purposes. The goal of this review is to conduct comparative analysis of the main methods for measuring the levels of oxidized and reduced pyridine nucleotides in cells and to identify key principles of their application for correct interpretation of the obtained data, including those used for studying central nervous system.
    Keywords:  brain; brain aging; chromatography; fluorometry; mass spectrometry; metabolomics; neurodegeneration; neuroplasticity; pyridine nucleotides
    DOI:  https://doi.org/10.1134/S0006297924604477
This page is being maintained by Thomas Krichel. It was last updated on 2025‒09‒29 at 10:39.