The first knock-in rat model for glutaric aciduria type I allows further insights into pathophysiology in brain and periphery

Mary Gonzalez Melo; Noémie Remacle; Hong-Phuc Cudré-Cung; Clothilde Roux; Martin Poms; Cristina Cudalbu; Madalena Barroso; Søren Waldemar Gersting; René Günther Feichtinger; Johannes Adalbert Mayr; Michele Costanzo; Marianna Caterino; Margherita Ruoppolo; Véronique Rüfenacht; Johannes Häberle; Olivier Braissant; Diana Ballhausen

doi:10.1016/j.ymgme.2021.03.017

The first knock-in rat model for glutaric aciduria type I allows further insights into pathophysiology in brain and periphery

Mol Genet Metab. 2021 Jun;133(2):157-181. doi: 10.1016/j.ymgme.2021.03.017. Epub 2021 Apr 18.

Authors

Mary Gonzalez Melo¹, Noémie Remacle², Hong-Phuc Cudré-Cung², Clothilde Roux³, Martin Poms⁴, Cristina Cudalbu⁵, Madalena Barroso⁶, Søren Waldemar Gersting⁷, René Günther Feichtinger⁸, Johannes Adalbert Mayr⁹, Michele Costanzo¹⁰, Marianna Caterino¹¹, Margherita Ruoppolo¹², Véronique Rüfenacht¹³, Johannes Häberle¹⁴, Olivier Braissant¹⁵, Diana Ballhausen¹⁶

Affiliations

¹ Pediatric Metabolic Unit, Pediatrics, Woman-Mother-Child Department, University of Lausanne and University Hospital of Lausanne, Switzerland. Electronic address: mary.gonzalez-melo@chuv.chm.
² Pediatric Metabolic Unit, Pediatrics, Woman-Mother-Child Department, University of Lausanne and University Hospital of Lausanne, Switzerland.
³ Service of Clinical Chemistry, University of Lausanne and University Hospital of Lausanne, Switzerland. Electronic address: Clothilde.Roux@chuv.ch.
⁴ Klinische Chemie und Biochemie Universitäts-Kinderspital Zürich, Switzerland. Electronic address: Martin.Poms@kispi.uzh.ch.
⁵ CIBM Center for Biomedical Imaging, Switzerland; Animal Imaging and Technology, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland. Electronic address: cristina.cudalbu@epfl.ch.
⁶ University Children's Research, UCR@Kinder-UKE, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. Electronic address: m.barroso@uke.de.
⁷ University Children's Research, UCR@Kinder-UKE, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. Electronic address: gersting@uke.de.
⁸ Department of Pediatrics, University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria. Electronic address: r.feichtinger@salk.at.
⁹ Department of Pediatrics, University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria. Electronic address: h.Mayr@salk.at.
¹⁰ Department of Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy; CEINGE - Biotecnologie Avanzate s.c.ar.l., 80145 Naples, Italy. Electronic address: michele.costanzo@unina.it.
¹¹ Department of Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy; CEINGE - Biotecnologie Avanzate s.c.ar.l., 80145 Naples, Italy. Electronic address: marianna.caterino@unina.it.
¹² Department of Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy; CEINGE - Biotecnologie Avanzate s.c.ar.l., 80145 Naples, Italy. Electronic address: margherita.ruoppolo@unina.it.
¹³ Division of Metabolism and Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland. Electronic address: veronique.ruefenacht@kispi.uzh.ch.
¹⁴ Division of Metabolism and Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland. Electronic address: Johannes.Haeberle@kispi.uzh.ch.
¹⁵ Service of Clinical Chemistry, University of Lausanne and University Hospital of Lausanne, Switzerland. Electronic address: Olivier.Braissant@chuv.ch.
¹⁶ Pediatric Metabolic Unit, Pediatrics, Woman-Mother-Child Department, University of Lausanne and University Hospital of Lausanne, Switzerland. Electronic address: diana.ballhausen@chuv.ch.

PMID: 33965309
DOI: 10.1016/j.ymgme.2021.03.017

Abstract

Glutaric aciduria type I (GA-I, OMIM # 231670) is an inborn error of metabolism caused by a deficiency of glutaryl-CoA dehydrogenase (GCDH). Patients develop acute encephalopathic crises (AEC) with striatal injury most often triggered by catabolic stress. The pathophysiology of GA-I, particularly in brain, is still not fully understood. We generated the first knock-in rat model for GA-I by introduction of the mutation p.R411W, the rat sequence homologue of the most common Caucasian mutation p.R402W, into the Gcdh gene of Sprague Dawley rats by CRISPR/CAS9 technology. Homozygous Gcdh^ki/ki rats revealed a high excretor phenotype, but did not present any signs of AEC under normal diet (ND). Exposure to a high lysine diet (HLD, 4.7%) after weaning resulted in clinical and biochemical signs of AEC. A significant increase of plasmatic ammonium concentrations was found in Gcdh^ki/ki rats under HLD, accompanied by a decrease of urea concentrations and a concomitant increase of arginine excretion. This might indicate an inhibition of the urea cycle. Gcdh^ki/ki rats exposed to HLD showed highly diminished food intake resulting in severely decreased weight gain and moderate reduction of body mass index (BMI). This constellation suggests a loss of appetite. Under HLD, pipecolic acid increased significantly in cerebral and extra-cerebral liquids and tissues of Gcdh^ki/ki rats, but not in WT rats. It seems that Gcdh^ki/ki rats under HLD activate the pipecolate pathway for lysine degradation. Gcdh^ki/ki rat brains revealed depletion of free carnitine, microglial activation, astroglyosis, astrocytic death by apoptosis, increased vacuole numbers, impaired OXPHOS activities and neuronal damage. Under HLD, Gcdh^ki/ki rats showed imbalance of intra- and extracellular creatine concentrations and indirect signs of an intracerebral ammonium accumulation. We successfully created the first rat model for GA-I. Characterization of this Gcdh^ki/ki strain confirmed that it is a suitable model not only for the study of pathophysiological processes, but also for the development of new therapeutic interventions. We further brought up interesting new insights into the pathophysiology of GA-I in brain and periphery.

Keywords: Astrogliosis; Cerebral organic aciduria; Glutaric aciduria type I; Hyperammonemia; Lysine degradation; Microglial activation.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Amino Acid Metabolism, Inborn Errors / genetics*
Amino Acid Metabolism, Inborn Errors / metabolism
Amino Acid Metabolism, Inborn Errors / pathology
Animals
Arginine / metabolism
Brain / metabolism*
Brain / pathology
Brain Diseases, Metabolic / genetics*
Brain Diseases, Metabolic / metabolism
Brain Diseases, Metabolic / pathology
Creatine / blood
Disease Models, Animal
Gene Knock-In Techniques
Gliosis / genetics*
Gliosis / metabolism
Gliosis / pathology
Glutaryl-CoA Dehydrogenase / deficiency*
Glutaryl-CoA Dehydrogenase / genetics*
Glutaryl-CoA Dehydrogenase / metabolism
Humans
Lysine / metabolism
Metabolism, Inborn Errors / genetics
Metabolism, Inborn Errors / metabolism
Rats

Substances

Arginine
Glutaryl-CoA Dehydrogenase
Lysine
Creatine

Supplementary concepts

Glutaric Acidemia I