Protective Effects of the Ketogenic Diet on Cognitive Impairment Induced by Status Epilepticus in Rats: Modulation of Neuroinflammation Through the NF-κB Signaling Pathway

Abstract

Epilepsy is a chronic neurological disorder characterized by abnormal synchronized neuronal discharges, leading to cognitive dysfunction. The ketogenic diet (KD) has shown promise as an effective treatment for drug-resistant epilepsy (DRE), reducing seizures and improving cognitive and behavioral outcomes in patients. However, the precise neuroprotective mechanisms are not fully understood. This study aimed to investigate the effects of KD on cognitive impairment and hippocampal neurocircuit damage in rats with status epilepticus (SE), with a focus on a nuclear factor-kappa B (NF-κB) signaling. SE was induced using pilocarpine, and rats were assigned to KD and control groups. After 7 and 20 days of KD treatment, cognitive function was assessed using the elevated plus-maze, Morris water maze, novel object recognition, and Y-maze tests. Hippocampal tissue was analyzed for structural damage of neurocircuit. NF-κB pathway activation was evaluated by western blot and immunofluorescence. Results indicated that KD significantly improved cognitive performance and reduced hippocampal damage. Additionally, KD inhibited NF-κB pathway activation, evidenced by decreased levels of NF-κB, p-IκB, and proinflammatory cytokines. These findings suggest that KD may alleviate cognitive deficits and hippocampal damage by modulating the NF-κB signaling, providing insights into its neuroprotective mechanisms and potential as an alternative treatment for epilepsy.

Keywords

epilepsy / ketogenic diet / neuroinflammation / nuclear factor-kappa B (NF-κB) pathway / status epilepticus

References

[1] Q. Qiao, S. Tian, Y. Zhang, et al., “A Ketogenic Diet May Improve Cognitive Function in Rats With Temporal Lobe Epilepsy by Regulating Endoplasmic Reticulum Stress and Synaptic Plasticity,” Molecular Neurobiology 61, no. 4 (2024): 2249–2264, https://doi.org/10.1007/s12035-023-03659-3.

[2] D. Guery and S. Rheims, “Clinical Management of Drug Resistant Epilepsy: A Review on Current Strategies,” Neuropsychiatric Disease and Treatment 17 (2021): 2229–2242, https://doi.org/10.2147/NDT.S256699.

[3] P. Ryvlin, M. Cucherat, and S. Rheims, “Risk of Sudden Unexpected Death in Epilepsy in Patients Given Adjunctive Antiepileptic Treatment for Refractory Seizures: A Meta-Analysis of Placebo-Controlled Randomised Trials,” Lancet Neurology 10, no. 11 (2011): 961–968, https://doi.org/10.1016/S1474-4422(11)70193-4.

[4] K. H. Elverman, Z. J. Resch, E. E. Quasney, D. S. Sabsevitz, J. R. Binder, and S. J. Swanson, “Temporal Lobe Epilepsy Is Associated With Distinct Cognitive Phenotypes,” Epilepsy & Behavior 96 (2019): 61–68, https://doi.org/10.1016/j.yebeh.2019.04.015.

[5] J.-A. Witt, C. E. Elger, and C. Helmstaedter, “Adverse Cognitive Effects of Antiepileptic Pharmacotherapy: Each Additional Drug Matters,” European Neuropsychopharmacology 25, no. 11 (2015): 1954–1959, https://doi.org/10.1016/j.euroneuro.2015.07.027.

[6] W. Jiang, J. Liao, D. Zhou, and J. Mu, “Ketogenic Diet Therapy for Epilepsy: Past 100 Years of Practice,” Acta Epileptologica 4, no. 1 (2022): 15, https://doi.org/10.1186/s42494-022-00089-x.

[7] J. Milder and M. Patel, “Modulation of Oxidative Stress and Mitochondrial Function by the Ketogenic Diet,” Epilepsy Research 100, no. 3 (2012): 295–303, https://doi.org/10.1016/j.eplepsyres.2011.09.021.

[8] E. G. Neal, H. Chaffe, R. H. Schwartz, et al., “The Ketogenic Diet for the Treatment of Childhood Epilepsy: A Randomised Controlled Trial,” Lancet Neurology 7, no. 6 (2008): 500–506, https://doi.org/10.1016/S1474-4422(08)70092-9.

[9] R. Polito, M. E. La Torre, F. Moscatelli, et al., “The Ketogenic Diet and Neuroinflammation: The Action of Beta-Hydroxybutyrate in a Microglial Cell Line,” International Journal of Molecular Sciences 24, no. 4 (2023): 3102, https://doi.org/10.3390/ijms24043102.

[10] M. Fortier, C.-A. Castellano, V. St-Pierre, et al., “A Ketogenic Drink Improves Cognition in Mild Cognitive Impairment: Results of a 6-Month RCT,” Alzheimer's & Dementia 17, no. 3 (2021): 543–552, https://doi.org/10.1002/alz.12206.

[11] M. C. L. Phillips, D. K. J. Murtagh, L. J. Gilbertson, F. J. S. Asztely, and C. D. P. Lynch, “Low-Fat Versus Ketogenic Diet in Parkinson's Disease: A Pilot Randomized Controlled Trial,” Movement Disorders 33, no. 8 (2018): 1306–1314, https://doi.org/10.1002/mds.27390.

[12] A. A. van Berkel, D. M. IJff, and J. M. Verkuyl, “Cognitive Benefits of the Ketogenic Diet in Patients With Epilepsy: A Systematic Overview,” Epilepsy & Behavior 87 (2018): 69–77, https://doi.org/10.1016/j.yebeh.2018.06.004.

[13] D. A. J. E. Lambrechts, L. H. P. Wielders, A. P. Aldenkamp, F. G. H. Kessels, R. J. A. de Kinderen, and M. J. M. Majoie, “The Ketogenic Diet as a Treatment Option in Adults With Chronic Refractory Epilepsy: Efficacy and Tolerability in Clinical Practice,” Epilepsy & Behavior 23, no. 3 (2012): 310–314, https://doi.org/10.1016/j.yebeh.2012.01.002.

[14] V. Monda, R. Polito, A. Lovino, et al., “Short-Term Physiological Effects of a Very Low-Calorie Ketogenic Diet: Effects on Adiponectin Levels and Inflammatory States,” International Journal of Molecular Sciences 21, no. 9 (2020): 3228, https://doi.org/10.3390/ijms21093228.

[15] H. Hersant and G. Grossberg, “The Ketogenic Diet and Alzheimer's Disease,” Journal of Nutrition, Health and Aging 26, no. 6 (2022): 606–614, https://doi.org/10.1007/s12603-022-1807-7.

[16] Y. Guo, X. Wang, P. Jia, et al., “Ketogenic Diet Aggravates Hypertension via NF-κB-Mediated Endothelial Dysfunction in Spontaneously Hypertensive Rats,” Life Sciences 258 (2020): 118124, https://doi.org/10.1016/j.lfs.2020.118124.

[17] Y. Lu, Y.-Y. Yang, M.-W. Zhou, et al., “Ketogenic Diet Attenuates Oxidative Stress and Inflammation After Spinal Cord Injury by Activating Nrf2 and Suppressing the NF-κB Signaling Pathways,” Neuroscience Letters 683 (2018): 13–18, https://doi.org/10.1016/j.neulet.2018.06.016.

[18] A. A. Walf and C. A. Frye, “The Use of the Elevated Plus Maze as an Assay of Anxiety-Related Behavior in Rodents,” Nature Protocols 2, no. 2 (2007): 322–328, https://doi.org/10.1038/nprot.2007.44.

[19] C. V. Vorhees and M. T. Williams, “Morris Water Maze: Procedures for Assessing Spatial and Related Forms of Learning and Memory,” Nature Protocols 1, no. 2 (2006): 848–858, https://doi.org/10.1038/nprot.2006.116.

[20] M. Leger, A. Quiedeville, V. Bouet, et al., “Object Recognition Test in Mice,” Nature Protocols 8, no. 12 (2013): 2531–2537, https://doi.org/10.1038/nprot.2013.155.

[21] A.-K. Kraeuter, P. C. Guest, and Z. Sarnyai, “The Y-Maze for Assessment of Spatial Working and Reference Memory in Mice,” in Pre-Clinical Models (Springer New York, 2018), 105–111, https://doi.org/10.1007/978-1-4939-8994-2_10.

[22] A. Golyala and P. Kwan, “Drug Development for Refractory Epilepsy: The Past 25 Years and Beyond,” Seizure 44 (2017): 147–156, https://doi.org/10.1016/j.seizure.2016.11.022.

[23] D. M. IJff, D. Postulart, D. A. J. E. Lambrechts, et al., “Cognitive and Behavioral Impact of the Ketogenic Diet in Children and Adolescents With Refractory Epilepsy: A Randomized Controlled Trial,” Epilepsy & Behavior 60 (2016): 153–157, https://doi.org/10.1016/j.yebeh.2016.04.033.

[24] Y. Tao, S. X. Leng, and H. Zhang, “Ketogenic Diet: An Effective Treatment Approach for Neurodegenerative Diseases,” Current Neuropharmacology 20, no. 12 (2022): 2303–2319, https://doi.org/10.2174/1570159X20666220830102628.

[25] J. H. Lee, S. E. Kim, C. H. Park, J. H. Yoo, and H. W. Lee, “Gray and White Matter Volumes and Cognitive Dysfunction in Drug-Naïve Newly Diagnosed Pediatric Epilepsy,” BioMed Research International 2015 (2015): 923861, https://doi.org/10.1155/2015/923861.

[26] A. K. Shetty, “Hippocampal Injury-Induced Cognitive and Mood Dysfunction, Altered Neurogenesis, and Epilepsy: Can Early Neural Stem Cell Grafting Intervention Provide Protection?,” Epilepsy & Behavior 38 (2014): 117–124, https://doi.org/10.1016/j.yebeh.2013.12.001.

[27] P.-P. Lenck-Santini and R. C. Scott, “Mechanisms Responsible for Cognitive Impairment in Epilepsy,” Cold Spring Harbor Perspectives in Medicine 5, no. 10 (2015): a022772, https://doi.org/10.1101/cshperspect.a022772.

[28] I. E. Holopainen, “Seizures in the Developing Brain: Cellular and Molecular Mechanisms of Neuronal Damage, Neurogenesis and Cellular Reorganization,” Neurochemistry International 52, no. 6 (2008): 935–947, https://doi.org/10.1016/j.neuint.2007.10.021.

[29] Progress in Inflammation Research (Springer), accessed February 13, 2025, https://www.springer.com/series/4983.

[30] Y.-H. Youm, K. Y. Nguyen, R. W. Grant, et al., “The Ketone Metabolite β-Hydroxybutyrate Blocks NLRP3 Inflammasome–Mediated Inflammatory Disease,” Nature Medicine 21, no. 3 (2015): 263–269, https://doi.org/10.1038/nm.3804.

[31] Y. Shen, D. Kapfhamer, A. M. Minnella, et al., “Bioenergetic State Regulates Innate Inflammatory Responses Through the Transcriptional Co-Repressor CtBP,” Nature Communications 8, no. 1 (2017): 624, https://doi.org/10.1038/s41467-017-00707-0.

[32] M. R. Ruth, A. M. Port, M. Shah, et al., “Consuming a Hypocaloric High Fat Low Carbohydrate Diet for 12 Weeks Lowers C-Reactive Protein, and Raises Serum Adiponectin and High Density Lipoprotein-Cholesterol in Obese Subjects,” Metabolism 62, no. 12 (2013): 1779–1787, https://doi.org/10.1016/j.metabol.2013.07.006.

[33] T. Li, X. Zhai, J. Jiang, et al., “Intraperitoneal Injection of IL-4/IFN-γ Modulates the Proportions of Microglial Phenotypes and Improves Epilepsy Outcomes in a Pilocarpine Model of Acquired Epilepsy,” Brain Research 1657 (2017): 120–129, https://doi.org/10.1016/j.brainres.2016.12.006.

[34] Y. Tian, B. Liu, Y. Li, et al., “Activation of RARα Receptor Attenuates Neuroinflammation After SAH via Promoting M1-to-M2 Phenotypic Polarization of Microglia and Regulating Mafb/Msr1/PI3K-Akt/NF-κB Pathway,” Frontiers in Immunology 13 (2022): 839796, https://doi.org/10.3389/fimmu.2022.839796.

[35] L. Yang, R. Zhou, Y. Tong, et al., “Neuroprotection by Dihydrotestosterone in LPS-Induced Neuroinflammation,” Neurobiology of Disease 140 (2020): 104814, https://doi.org/10.1016/j.nbd.2020.104814.

[36] Y. Wang, D. Sadike, B. Huang, et al., “Regulatory T Cells Alleviate Myelin Loss and Cognitive Dysfunction by Regulating Neuroinflammation and Microglial Pyroptosis via TLR4/MyD88/NF-κB Pathway in LPC-Induced Demyelination,” Journal of Neuroinflammation 20, no. 1 (2023): 41, https://doi.org/10.1186/s12974-023-02721-0.

[37] C. Le Foll, A. A. Dunn-Meynell, H. M. Miziorko, and B. E. Levin, “Regulation of Hypothalamic Neuronal Sensing and Food Intake by Ketone Bodies and Fatty Acids,” Diabetes 63, no. 4 (2014): 1259–1269, https://doi.org/10.2337/db13-1090.

[38] L.-P. Bernier, E. M. York, A. Kamyabi, H. B. Choi, N. L. Weilinger, and B. A. MacVicar, “Microglial Metabolic Flexibility Supports Immune Surveillance of the Brain Parenchyma,” Nature Communications 11, no. 1 (2020): 1559, https://doi.org/10.1038/s41467-020-15267-z.

[39] T. R. Hammond, S. E. Marsh, and B. Stevens, “Immune Signaling in Neurodegeneration,” Immunity 50, no. 4 (2019): 955–974, https://doi.org/10.1016/j.immuni.2019.03.016.

[40] F. Shao, X. Wang, H. Wu, Q. Wu, and J. Zhang, “Microglia and Neuroinflammation: Crucial Pathological Mechanisms in Traumatic Brain Injury-Induced Neurodegeneration,” Frontiers in Aging Neuroscience 14 (2022): 825086, https://doi.org/10.3389/fnagi.2022.825086.

[41] A. Monda, M. E. La Torre, A. Messina, et al., “Exploring the Ketogenic Diet's Potential in Reducing Neuroinflammation and Modulating Immune Responses,” Frontiers in Immunology 15 (2024): 1425816, https://doi.org/10.3389/fimmu.2024.1425816.

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2025 The Author(s). Pediatric Discovery published by John Wiley & Sons Australia, Ltd on behalf of Children's Hospital of Chongqing Medical University.