scholarly journals A mitochondrial long-chain fatty acid oxidation defect leads to uncharged tRNA accumulation and activation of the integrated stress response in the mouse heart

2021 ◽  
Author(s):  
Pablo Ranea-Robles ◽  
Natalya N Pavlova ◽  
Aaron Bender ◽  
Brandon Stauffer ◽  
Chunli Yu ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Stress Response ◽  
High Energy ◽  
Acid Oxidation ◽  
Mouse Heart ◽  
Integrated Stress Response ◽  
Mitochondrial Fatty Acid ◽  
Short Period ◽  
Chain Acyl ◽  
Long Chain

The heart relies mainly on mitochondrial fatty acid β-oxidation (FAO) for its high energy requirements. Cardiomyopathy and arrhythmias can be severe complications in patients with inherited defects in mitochondrial long-chain FAO, reinforcing the importance of FAO for cardiac health. However, the pathophysiological mechanisms that underlie the cardiac abnormalities in long-chain FAO disorders remain largely unknown. Here, we investigated the cardiac transcriptional adaptations to the FAO defect in the long-chain acyl-CoA dehydrogenase (LCAD) knockout (KO) mouse. We found a prominent activation of the integrated stress response (ISR) mediated by the eIF2α/ATF4 axis in both fed and fasted states, accompanied by a reduction in cardiac protein synthesis during a short period of food withdrawal. Notably, we found an accumulation of uncharged tRNAs in LCAD KO hearts, consistent with a reduced availability of cardiac amino acids, in particular, glutamine. Our results show that perturbations in amino acid metabolism caused by long-chain FAO deficiency impact cardiac metabolic signaling, in particular the ISR, and may play a role in the associated cardiac pathology

scholarly journals Medium-Chain Acyl-CoA Dehydrogenase Deficiency in an Infant with Dilated Cardiomyopathy

2009 ◽  
Vol 2009 ◽  
pp. 1-3 ◽  
Author(s):  
Marcello Marcì ◽  
Patrizia Ajovalasit
Keyword(s):  
Fatty Acid ◽  
Dilated Cardiomyopathy ◽  
Dehydrogenase Deficiency ◽  
Acid Oxidation ◽  
Inherited Disorders ◽  
Mitochondrial Fatty Acid Oxidation ◽  
Medium Chain ◽  
Mitochondrial Fatty Acid ◽  
Chain Acyl ◽  
Long Chain

We report about an infant affected by dilated cardiomyopathy (CMP) in whom metabolic investigations evidenced medium-chain-acyl-CoA dehydrogenase deficiency (MCADD), that is one of three types of inherited disorders of mitochondrial fatty-acid -oxidation. Long-chain and very long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficits are recognized as responsible of hypertrophic or, less frequently, dilated cardiomyopathy (CMP) in childhood. Otherwise, to our knowledge, no case of MCADD associated to dilated CMP has been reported in literature.

scholarly journals Nrf2 affects the efficiency of mitochondrial fatty acid oxidation

2014 ◽  
Vol 457 (3) ◽  
pp. 415-424 ◽  
Author(s):  
Marthe H. R. Ludtmann ◽  
Plamena R. Angelova ◽  
Ying Zhang ◽  
Andrey Y. Abramov ◽  
Albena T. Dinkova-Kostova
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Oxidation ◽  
Saturated Fatty Acids ◽  
Acid Oxidation ◽  
Mitochondrial Fatty Acid Oxidation ◽  
Atp Production ◽  
Mitochondrial Fatty Acid ◽  
Mitochondrial Oxidation ◽  
Long Chain

Transcription factor Nrf2 affects fatty acid oxidation; the mitochondrial oxidation of long-chain (palmitic) and short-chain (hexanoic) saturated fatty acids is depressed in the absence of Nrf2 and accelerated when Nrf2 is constitutively activated, affecting ATP production and FADH2 utilization.

scholarly journals Recent Advances in the Pathophysiology of Fatty Acid Oxidation Defects: Secondary Alterations of Bioenergetics and Mitochondrial Calcium Homeostasis Caused by the Accumulating Fatty Acids

2020 ◽  
Vol 11 ◽  
Author(s):  
Alexandre Umpierrez Amaral ◽  
Moacir Wajner
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Oxidation ◽  
Calcium Homeostasis ◽  
Acid Oxidation ◽  
Cultured Fibroblasts ◽  
Medium Chain ◽  
Chain Acyl ◽  
Energy Deprivation ◽  
Long Chain

Deficiencies of medium-chain acyl-CoA dehydrogenase, mitochondrial trifunctional protein, isolated long-chain 3-hydroxyacyl-CoA dehydrogenase, and very long-chain acyl-CoA dehydrogenase activities are considered the most frequent fatty acid oxidation defects (FAOD). They are biochemically characterized by the accumulation of medium-chain, long-chain hydroxyl, and long-chain fatty acids and derivatives, respectively, in tissues and biological fluids of the affected patients. Clinical manifestations commonly include hypoglycemia, cardiomyopathy, and recurrent rhabdomyolysis. Although the pathogenesis of these diseases is still poorly understood, energy deprivation secondary to blockage of fatty acid degradation seems to play an important role. However, recent evidence indicates that the predominant fatty acids accumulating in these disorders disrupt mitochondrial functions and are involved in their pathophysiology, possibly explaining the lactic acidosis, mitochondrial morphological alterations, and altered mitochondrial biochemical parameters found in tissues and cultured fibroblasts from some affected patients and also in animal models of these diseases. In this review, we will update the present knowledge on disturbances of mitochondrial bioenergetics, calcium homeostasis, uncoupling of oxidative phosphorylation, and mitochondrial permeability transition induction provoked by the major fatty acids accumulating in prevalent FAOD. It is emphasized that further in vivo studies carried out in tissues from affected patients and from animal genetic models of these disorders are necessary to confirm the present evidence mostly achieved from in vitro experiments.

Medium- and Short-Chain L-3-Hydroxyl-Acetyl-Coenzyme A Deficiency: A New Identified Mutation in Four Cases

2019 ◽  
Vol 152 (Supplement_1) ◽  
pp. S9-S9
Author(s):  
Sheng Feng ◽  
Deborah Cooper ◽  
Lu Tan ◽  
Gail Meyers ◽  
Michael Bennett
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Oxidation ◽  
Coenzyme A ◽  
Short Chain ◽  
Acid Oxidation ◽  
Sequencing Analysis ◽  
Mitochondrial Fatty Acid Oxidation ◽  
Mitochondrial Fatty Acid ◽  
Chain Acyl ◽  
Unusual Phenotype

Abstract Medium- and short-chain L-3-hydroxyacyl-coenzyme A dehydrogenase (M/SCHAD, SCHAD) deficiency is a mitochondrial fatty acid oxidation disorder (FAOD). This enzyme catalyzes the penultimate step in fatty acid oxidation, the NAD+ dependent conversion of L-3-hydroxyacyl-CoA to 3-ketoacyl-CoA for medium- and short-chain acyl-CoA intermediates (C4-C12). The clinical presentations of most patients are recurrent hypoglycemia associated with hyperinsulinism. We presented four infants with C4 acyl-carnitine elevation identified by newborn screening that also showed an unusual phenotype of congenital hypotonia and gross developmental delay. Enzymatic studies confirmed the disease. Sequencing analysis of all the HADH coding exons on the four patients revealed a homozygous variant of a novel change (c.908G>T, p.Gly303Val). Western blot analysis subsequently confirmed the lack of the SCHAD protein. In addition, there is another previously reported benign variant (c.257T>C) identified in three infants. Therefore, we postulate that the HADH variant (c.908G>T) is indeed pathogenic and associated with a severe phenotype as evidenced by the cases described herein. Population screening for the c.908G>T mutation suggests this mutation to be common among Puerto Ricans. We recommend that SCHAD deficiency is included as part of the differential diagnosis of all infants with congenital hypotonia.

scholarly journals Acyl-CoA dehydrogenase activity in the riboflavin-deficient rat. Effects of starvation

1987 ◽  
Vol 244 (2) ◽  
pp. 387-391 ◽  
Author(s):  
N S Ross ◽  
C L Hoppel
Keyword(s):  
Fatty Acid ◽  
Dehydrogenase Activity ◽  
Fatty Acid Oxidation ◽  
Specific Activity ◽  
Short Chain ◽  
Acid Oxidation ◽  
Riboflavin Deficiency ◽  
Mitochondrial Fatty Acid ◽  
Chain Acyl ◽  
Riboflavin Deficient

Riboflavin deficiency in weanling rats causes a metabolic disorder characterized by failure to oxidize fatty acids. The disorder is similar to that seen in several human diseases, some of which are responsive to pharmacological doses of riboflavin. Previous analysis of the riboflavin-deficient rat has shown that the failure of fatty acid oxidation is due to a decrease in the activity of the acyl-CoA dehydrogenases of beta-oxidation. The activity of these flavoenzymes in liver rapidly decreases when a riboflavin-deficient diet is initiated. The objectives of these experiments were to analyse the effects of starvation on liver mitochondria isolated from the riboflavin-deficient rat. Our studies show that the decreased mitochondrial fatty acid oxidation induced by riboflavin deficiency is partially reversed by starvation. The extent of this reversal is proportional to the duration of starvation. The starvation-associated increase in fatty acid oxidation is mediated by an increase in the mitochondrial short-chain acyl-CoA dehydrogenase activity. The activity of this enzyme is increased such that the ratio of short-chain acyl-CoA dehydrogenase apoenzyme to holoenzyme does not change. We conclude that short-chain acyl-CoA dehydrogenase activity is limiting for fatty acid oxidation when its activity falls below a critical point. The increased mitochondrial specific activity of short-chain acyl-CoA dehydrogenase during starvation may result from an increased availability of flavin coenzyme or an increase in enzyme catalytic efficiency.

scholarly journals Drug triggered pruritus, rash, papules, and blisters – is AGEP a clash of an altered sphingolipid-metabolism and lysosomotropism of drugs accumulating in the skin?

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Markus Blaess ◽  
Lars Kaiser ◽  
Oliver Sommerfeld ◽  
René Csuk ◽  
Hans-Peter Deigner
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Uv Radiation ◽  
Sphingolipid Metabolism ◽  
Acid Oxidation ◽  
Long Chain Fatty Acids ◽  
Mitochondrial Fatty Acid ◽  
The Individual ◽  
Long Chain ◽  
Chain Fatty Acids

AbstractRash, photosensitivity, erythema multiforme, and the acute generalized exanthematous pustulosis (AGEP) are relatively uncommon adverse reactions of drugs. To date, the etiology is not well understood and individual susceptibility still remains unknown. Amiodarone, chlorpromazine, amitriptyline, and trimipramine are classified lysosomotropic as well as photosensitizing, however, they fail to trigger rash and pruritic papules in all individuals. Lysosomotropism is a common charcteristic of various drugs, but independent of individuals. There is evidence that the individual ability to respond to external oxidative stress is crosslinked with the elongation of long-chain fatty acids to very long-chain fatty acids by ELOVLs. ELOVL6 and ELOVL7 are sensitive to ROS induced depletion of cellular NADPH and insufficient regeneration via the pentose phosphate pathway and mitochondrial fatty acid oxidation. Deficiency of NADPH in presence of lysosomotropic drugs promotes the synthesis of C16-ceramide in lysosomes and may contribute to emerging pruritic papules of AGEP. However, independently from a lysosomomotropic drug, severe depletion of ATP and NAD(P)H, e.g., by UV radiation or a potent photosensitizer can trigger likewise the collapse of the lysosomal transmembrane proton gradient resulting in lysosomal C16-ceramide synthesis and pruritic papules. This kind of papules are equally present in polymorphous light eruption (PMLE/PLE) and acne aestivalis (Mallorca acne). The suggested model of a compartmentalized ceramide metabolism provides a more sophisticated explanation of cutaneous drug adverse effects and the individual sensitivity to UV radiation. Parameters such as pKa and ClogP of the triggering drug, cutaneous fatty acid profile, and ceramide profile enables new concepts in risk assessment and scoring of AGEP as well as prophylaxis outcome.

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