1. Glutamine Supplementation as a Novel Metabolic Therapeutic Strategy for LIG3-Dependent Chronic Intestinal Pseudo-Obstruction.
- Author
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Diquigiovanni C, Rizzardi N, Cataldi-Stagetti E, Gozzellino L, Isidori F, Valenti F, Orsini A, Astolfi A, Giangregorio T, Pironi L, Boschetti E, Arrigo S, Maresca A, Magnoni P, Costanzini A, Carelli V, Taniguchi-Ikeda M, Fato R, Bergamini C, De Giorgio R, and Bonora E
- Subjects
- Humans, Male, Chronic Disease, Mitochondria metabolism, Mitochondria drug effects, Female, Cells, Cultured, Dietary Supplements, Gene Expression Profiling, Energy Metabolism drug effects, Case-Control Studies, Intestinal Pseudo-Obstruction genetics, Intestinal Pseudo-Obstruction metabolism, Intestinal Pseudo-Obstruction drug therapy, Fibroblasts metabolism, Fibroblasts drug effects, Fibroblasts pathology, Glutamine metabolism, Mutation, Mitophagy drug effects, DNA Ligase ATP genetics, DNA Ligase ATP metabolism
- Abstract
Background & Aims: We recently identified a recessive syndrome due to DNA ligase 3 (LIG3) mutations in patients with chronic intestinal pseudo-obstruction, leukoencephalopathy, and neurogenic bladder. LIG3 mutations affect mitochondrial DNA maintenance, leading to defective energy production. We aimed at identifying altered molecular pathways and developing possible targeted treatments to revert/ameliorate the cellular energy impairment., Methods: Whole transcriptome analysis was performed on patient-derived fibroblasts total RNA and controls. Mitochondrial function, mitophagy, and l-glutamine supplementation effects were analyzed by live cell analysis, immunostaining, and Western blot. Patients were treated with Dipeptiven (Fresenius-Kabi) according to standard protocols. Patients' symptoms were analyzed by the Gastrointestinal Symptom Rating Scale questionnaire., Results: We identified deregulated transcripts in mutant fibroblasts vs controls, including overexpression of genes involved in extracellular matrix development and remodeling and mitochondrial functions. Gut biopsy specimens of LIG3-mutant patients documented collagen and elastic fiber accumulation. Mutant fibroblasts exhibited impaired mitochondrial mitophagy indicative of dysfunctional turnover and altered Ca
2+ homeostasis. Supplementation with l-glutamine (6 mmol/L), previously shown to increase mitochondrial DNA-defective cell survival, improved growth rate and adenosine 5'-triphosphate production in LIG3-mutant fibroblasts. These data led us to provide parenterally a dipeptide containing l-glutamine to 3 siblings carrying biallelic LIG3 mutations. Compared with baseline, gastrointestinal and extra-gastrointestinal symptoms significantly improved after 8 months of treatment., Conclusions: LIG3 deficiency leads to mitochondrial dysfunction. High levels l-glutamine supplementation were beneficial in LIG3-mutant cells and improved symptom severity without noticeable adverse effects. Our results provide a proof of concept to design ad hoc clinical trials with l-glutamine in LIG3-mutant patients., (Copyright © 2025 AGA Institute. Published by Elsevier Inc. All rights reserved.)- Published
- 2025
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