Remodeling of lipid landscape in high fat fed very-long chain acyl-CoA dehydrogenase null mice favors pro-arrhythmic polyunsaturated fatty acids and their downstream metabolites

Bruno Lefort (1, 2, 3) , Roselle Gélinas (2, 4) , Anik Forest (2) , Bertrand Bouchard (2) , Caroline Daneault (2) , Isabelle Robillard Frayne (2) , Jérôme Roy (5, 6) , Camille Oger (5) , Karine Greffard (7) , Jean-Marie Galano (5) , Thierry Durand (5) , François Labarthe (3) , Jean-François Bilodeau (7) , Matthieu Ruiz (2, 8) , Christine Des Rosiers (8, 2)

1 CHRU Tours - Centre Hospitalier Régional Universitaire de Tours
2 Montreal Heart Institute - Institut de Cardiologie de Montréal
3 N2Cox - Niche, Nutrition, Cancer et métabolisme oxydatif
4 Centre de recherche du CHU Sainte-Justine / Research Center of the Sainte-Justine University Hospital [Montreal, Canada]
5 IBMM - Institut des Biomolécules Max Mousseron [Pôle Chimie Balard]
6 NuMéA - Nutrition, Métabolisme, Aquaculture
7 CHU de Québec–Université Laval
8 UdeM - Université de Montréal

Very-long chain acyl-CoA dehydrogenase (VLCAD) catalyzes the initial step of mitochondrial long chain (LC) fatty acid β-oxidation (FAO). Inherited VLCAD deficiency (VLCADD) predisposes to neonatal arrhythmias whose pathophysiology is still not understood. We hypothesized that VLCADD results in global disruption of cardiac complex lipid homeostasis, which may set conditions predisposing to arrhythmia. To test this, we assessed the cardiac lipidome and related molecular markers in seven-month-old VLCAD-/- mice, which mimic to some extent the human cardiac phenotype. Mice were sacrificed in the fed or fasted state after receiving for two weeks a chow or a high-fat diet (HFD), the latter condition being known to worsen symptoms in human VLCADD. Compared to their littermate counterparts, HFD/fasted VLCAD-/- mouse hearts displayed the following lipid alterations: (1) Lower LC, but higher VLC-acylcarnitines accumulation, (2) higher levels of arachidonic acid (AA) and lower docosahexaenoic acid (DHA) contents in glycerophospholipids (GPLs), as well as (3) corresponding changes in pro-arrhythmogenic AA-derived isoprostanes and thromboxane B2 (higher), and anti-arrythmogenic DHA-derived neuroprostanes (lower). These changes were associated with remodeling in the expression of gene or protein markers of (1) GPLs remodeling: higher calcium-dependent phospholipase A2 and lysophosphatidylcholine-acyltransferase 2, (2) calcium handling perturbations, and (3) endoplasmic reticulum stress. Altogether, these results highlight global lipid dyshomeostasis beyond FAO in VLCAD-/- mouse hearts, which may set conditions predisposing the hearts to calcium mishandling and endoplasmic reticulum stress and thereby may contribute to the pathogenesis of arrhythmias in VLCADD in mice as well as in humans.

Mots clés: VLCAD deficiency; Lipidomic; Prostane; Calcium homeostasis; Endoplasmic reticulum stress

Domaines: Sciences du Vivant [q-bio]

Bruno Lefort, Roselle Gélinas, Anik Forest, Bertrand Bouchard, Caroline Daneault, et al.. Remodeling of lipid landscape in high fat fed very-long chain acyl-CoA dehydrogenase null mice favors pro-arrhythmic polyunsaturated fatty acids and their downstream metabolites. Biochimica et Biophysica Acta - Molecular Basis of Disease, 2023, 1869 (8), pp.166843. ⟨10.1016/j.bbadis.2023.166843⟩. ⟨hal-04189749⟩