Lymphoblastoid Cell Lines from Patients with Dravet Syndrome show Deficits in Mitochondrial Respiration and Glycolysis
Abstract number :
1.467
Submission category :
2. Translational Research / 2D. Models
Year :
2022
Submission ID :
2232916
Source :
www.aesnet.org
Presentation date :
12/3/2022 12:00:00 PM
Published date :
Nov 22, 2022, 05:28 AM
Authors :
Anna Figueroa, BS – University of Colorado; Rajeswari Banerji, PhD – Department of Pharmaceutical Sciences – University of Colorado; Ruth Fulton, MS – Department of Pharmaceutical Sciences – University of Colorado; Kelly Knupp, MD MSCS FAES – Associate Professor, Pediatrics and Neurology, University of Colorado; Manisha Patel, PhD – Professor, Department of Pharmaceutical Sciences, University of Colorado
This is a Late Breaking abstract
Rationale: Mitochondria are essential in a variety of functions that range from energy metabolism to redox regulation. While alterations in mitochondrial oxidative phosphorylation and glycolysis have been reported in acquired epilepsy, the role of metabolic imbalance in genetic forms of epilepsy, like Dravet syndrome (DS), has not been systematically investigated. DS is a severe form of pediatric epilepsy and is often associated with de novo mutations in the voltage-gated sodium channel gene, SCN1A. Patients with DS suffer from frequent and spontaneous early-life seizures. Interestingly, a percentage of patients with DS on Ketogenic Diet achieve a high degree of clinical efficacy; this supports the need for further investigation of metabolic pathways in patients with DS. We have previously demonstrated deficits in mitochondrial respiration and glycolysis in a zebrafish model of DS (Kumar et al., 2016; Banerji et al., 2021). However, whether these changes occur in patient-derived cells in systemic circulation is unknown. Patient-derived lymphoblast cell lines (LCLs) are a unique model that can reflect bioenergetic changes occurring in the context of neurological diseases. In this study we describe the establishment of a LCL model to evaluate bioenergetic differences between DS patients (DS LCLs) and those from age/sex-matched healthy volunteers (Con LCLs).
Methods: DS-LCLs derived from patients diagnosed with DS [mean (SEM) age, 7.5 (1.67) years] were obtained from a blood sample from children that meet the following criteria: (1) known SCN1A mutation, (2) meet standard clinical characteristics for DS and (3) are not on a KD. Key parameters of mitochondrial respiration (oxygen consumption rate) and glycolysis (extracellular acidification rate) in LCLs were measured using the Extracellular Flux 96 Analyzer.
Results: Overall, key parameters of mitochondrial function were decreased in DS LCLs. ATP-linked respiration was found to be significantly decreased (mean% of Con-LCLs ± SEM; 32.68 ± 9.19, P=0.02, n=6), maximal respiratory capacity was also decreased (mean% of Con-LCLs ± SEM; 35.48 ± 7.24, P=0.001, n=6), in addition to spare capacity which decreased by 42.60% ± 7.24, P=0.0001, n=6. When comparing glycolytic parameters, glycolytic reserve was significantly decreased in DS LCLs (mean % of Con-LCLs ± SEM; 54.77 ± 17.13, P=0.02, n=6), however; we did not see a significant difference in both glycolysis and glycolytic capacity.
Conclusions: DS LCLs appear to have defects in both major energy-producing pathways. Mitochondrial parameters related to ATP production, such as, ATP-linked respiration, maximal respiratory capacity, and spare capacity were significantly altered. In addition, the DS LCLs capability to respond to a glycolysis-related energetic demand was significantly impaired. The findings reported here, further support the investigation of metabolism in DS using a novel model of DS-derived cell lines to target energy-producing pathways to evaluate new therapeutic options for DS.
Funding: DSF grant (MP, KK), DSF Postdoctoral fellowship (RB), AFPE (AGF)
Translational Research