1
|
Smith AM, Donley ELR, Ney DM, Amaral DG, Burrier RE, Natowicz MR. Metabolomic biomarkers in autism: identification of complex dysregulations of cellular bioenergetics. Front Psychiatry 2023; 14:1249578. [PMID: 37928922 PMCID: PMC10622772 DOI: 10.3389/fpsyt.2023.1249578] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 08/30/2023] [Indexed: 11/07/2023] Open
Abstract
Autism Spectrum Disorder (ASD or autism) is a phenotypically and etiologically heterogeneous condition. Identifying biomarkers of clinically significant metabolic subtypes of autism could improve understanding of its underlying pathophysiology and potentially lead to more targeted interventions. We hypothesized that the application of metabolite-based biomarker techniques using decision thresholds derived from quantitative measurements could identify autism-associated subpopulations. Metabolomic profiling was carried out in a case-control study of 499 autistic and 209 typically developing (TYP) children, ages 18-48 months, enrolled in the Children's Autism Metabolome Project (CAMP; ClinicalTrials.gov Identifier: NCT02548442). Fifty-four metabolites, associated with amino acid, organic acid, acylcarnitine and purine metabolism as well as microbiome-associated metabolites, were quantified using liquid chromatography-tandem mass spectrometry. Using quantitative thresholds, the concentrations of 4 metabolites and 149 ratios of metabolites were identified as biomarkers, each identifying subpopulations of 4.5-11% of the CAMP autistic population. A subset of 42 biomarkers could identify CAMP autistic individuals with 72% sensitivity and 90% specificity. Many participants were identified by several metabolic biomarkers. Using hierarchical clustering, 30 clusters of biomarkers were created based on participants' biomarker profiles. Metabolic changes associated with the clusters suggest that altered regulation of cellular metabolism, especially of mitochondrial bioenergetics, were common metabolic phenotypes in this cohort of autistic participants. Autism severity and cognitive and developmental impairment were associated with increased lactate, many lactate containing ratios, and the number of biomarker clusters a participant displayed. These studies provide evidence that metabolic phenotyping is feasible and that defined autistic subgroups can lead to enhanced understanding of the underlying pathophysiology and potentially suggest pathways for targeted metabolic treatments.
Collapse
Affiliation(s)
- Alan M. Smith
- Stemina Biomarker Discovery, Inc, Madison, WI, United States
| | | | - Denise M. Ney
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, United States
| | - David G. Amaral
- Department of Psychiatry and Behavioral Sciences, The MIND Institute, University of California, Davis, Davis, CA, United States
| | | | - Marvin R. Natowicz
- Pathology and Laboratory Medicine, Genomic Medicine, Neurological and Pediatrics Institutes, Cleveland Clinic, Cleveland, OH, United States
| |
Collapse
|
2
|
Nogay NH, Nahikian-Nelms M. Effects of nutritional interventions in children and adolescents with autism spectrum disorder: an overview based on a literature review. INTERNATIONAL JOURNAL OF DEVELOPMENTAL DISABILITIES 2022; 69:811-824. [PMID: 37885847 PMCID: PMC10599198 DOI: 10.1080/20473869.2022.2036921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Accepted: 01/27/2022] [Indexed: 10/28/2023]
Abstract
Background: Nutrition is important in autism spectrum disorder (ASD). Because nutritional problems of children with ASD can lead to nutritional deficiencies and this can also directly or indirectly affect symptoms related to autism. We investigated the effect of diet and supplementation treatments on gastrointestinal, behavioral or sleep problems based on the results of literature review. Methods: We generated four questions based on literature. We carried out title and abstract-based search using the Web of Science database. Of 4580 abstracts were identified, 192 papers were reviewed and 55 papers precisely meeting the inclusion criteria. Results: The studies examining the effects of vitamins, minerals, probiotics, and other supplements on ASD symptoms had different dosages, different treatment durations, small sample sizes and used different scales for evaluation. The results of the studies of the effectiveness of Gluten-Free and Casein-Free (GFCF) and ketogenic diet to reduce gastrointestinal, behavioral and sleeping problems in children and adolescents were contradictory. Conclusions: It is not possible to suggest the GFCF and/or ketogenic diet, vitamins, minerals and probiotics to individual with ASD based on the available evidence. By planning a sufficient and balanced diet, it should be aimed to prevent nutrient deficiency and to ensure growth in accordance with the age in children with ASD.
Collapse
Affiliation(s)
- Nalan Hakime Nogay
- Faculty of Health Sciences, Department of Nutrition and Dietetics, Erciyes University, Kayseri, Turkey
| | - Marcia Nahikian-Nelms
- School of Health and Rehabilitation Sciences, College of Medicine, the Ohio State University, Columbus, OH, USA
| |
Collapse
|
3
|
Vasiljevski ER, Burns J, Bray P, Donlevy G, Mudge AJ, Jones KJ, Summers MA, Biggin A, Munns CF, McKay MJ, Baldwin JN, Little DG, Schindeler A. L-carnitine supplementation for muscle weakness and fatigue in children with neurofibromatosis type 1: A Phase 2a clinical trial. Am J Med Genet A 2021; 185:2976-2985. [PMID: 34155781 PMCID: PMC9290089 DOI: 10.1002/ajmg.a.62392] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 05/17/2021] [Accepted: 05/27/2021] [Indexed: 02/06/2023]
Abstract
Reduced muscle tone, muscle weakness, and physical fatigue can impact considerably on quality of life for children with neurofibromatosis type 1 (NF1). Human muscle biopsies and mouse models of NF1 deficiency in muscle show intramyocellular lipid accumulation, and preclinical data have indicated that L-carnitine supplementation can ameliorate this phenotype. The aim of this study is to examine whether daily L-carnitine supplementation is safe and feasible, and will improve muscle strength and reduce fatigue in children with NF1. A 12-week Phase 2a trial was conducted using 1000 mg daily oral levocarnitine tartrate supplementation. Recruited children were between 8 and 12 years old with a clinical diagnosis of NF1, history of muscle weakness and fatigue, and naïve to L-carnitine. Primary outcomes were safety (self-reporting, biochemical testing) and compliance. Secondary outcomes included plasma acylcarnitine profiles, functional measures (muscle strength, long jump, handwriting speed, 6-minute-walk test [6MWT]), and parent-reported questionnaires (PedsQL™, CBCL/6-18). Six children completed the trial with no self-reported adverse events. Biochemical tests for kidney and liver function were normal, and the average compliance was 95%. Plasma acylcarnitine levels were low, but within a range not clinically linked to carnitine deficiency. For strength measures, there was a mean 53% increase in dorsiflexion strength (95% confidence interval [CI] 8.89-60.75; p = 0.02) and mean 66% increase in plantarflexion strength (95% CI 12.99-134.1; p = 0.03). In terms of muscle performance, there was a mean 10% increase in long jump distance (95% CI 2.97-16.03; p = 0.01) and 6MWT distance (95% CI 5.88-75.45; p = 0.03). Comparison with the 1000 Norms Project data showed a significant improvement in Z-score for all of these measures. Parent reports showed no negative impact on quality of life, and the perceived benefits led to the majority of individuals remaining on L-carnitine after the study. Twelve weeks of L-carnitine supplementation is safe and feasible in children with NF1, and a Phase 3 trial should confirm the efficacy of treatment.
Collapse
Affiliation(s)
- Emily R Vasiljevski
- Orthopaedic Research & Biotechnology, The Children's Hospital at Westmead, Sydney, New South Wales, Australia.,Discipline of Child and Adolescent Health, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Joshua Burns
- University of Sydney School of Health Sciences, Faculty of Medicine and Health, Sydney, New South Wales, Australia.,Paediatric Gait Analysis Service of NSW, Sydney Children's Hospitals Network (Randwick and Westmead), Sydney, New South Wales, Australia
| | - Paula Bray
- University of Sydney School of Health Sciences, Faculty of Medicine and Health, Sydney, New South Wales, Australia.,Kids Neuroscience Centre, The Children's Hospital at Westmead, Sydney, New South Wales, Australia
| | - Gabrielle Donlevy
- University of Sydney School of Health Sciences, Faculty of Medicine and Health, Sydney, New South Wales, Australia.,Kids Neuroscience Centre, The Children's Hospital at Westmead, Sydney, New South Wales, Australia
| | - Anita J Mudge
- Paediatric Gait Analysis Service of NSW, Sydney Children's Hospitals Network (Randwick and Westmead), Sydney, New South Wales, Australia
| | - Kristi J Jones
- Discipline of Child and Adolescent Health, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.,Kids Neuroscience Centre, The Children's Hospital at Westmead, Sydney, New South Wales, Australia
| | - Matthew A Summers
- Healthy Ageing Theme, The Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.,St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Andrew Biggin
- Institute of Endocrinology and Diabetes, University of Sydney, The Children's Hospital at Westmead, Sydney, New South Wales, Australia.,The Children's Hospital at Westmead Clinical School, The University of Sydney, Sydney, New South Wales, Australia
| | - Craig F Munns
- Institute of Endocrinology and Diabetes, University of Sydney, The Children's Hospital at Westmead, Sydney, New South Wales, Australia.,The Children's Hospital at Westmead Clinical School, The University of Sydney, Sydney, New South Wales, Australia
| | - Marnee J McKay
- University of Sydney School of Health Sciences, Faculty of Medicine and Health, Sydney, New South Wales, Australia
| | - Jennifer N Baldwin
- Faculty of Health and Medicine, The University of Newcastle, Newcastle, New South Wales, Australia
| | - David G Little
- Orthopaedic Research & Biotechnology, The Children's Hospital at Westmead, Sydney, New South Wales, Australia.,Discipline of Child and Adolescent Health, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Aaron Schindeler
- Orthopaedic Research & Biotechnology, The Children's Hospital at Westmead, Sydney, New South Wales, Australia.,Discipline of Child and Adolescent Health, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| |
Collapse
|
4
|
Potential Role of L-Carnitine in Autism Spectrum Disorder. J Clin Med 2021; 10:jcm10061202. [PMID: 33805796 PMCID: PMC8000371 DOI: 10.3390/jcm10061202] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/12/2021] [Accepted: 03/12/2021] [Indexed: 12/17/2022] Open
Abstract
L-carnitine plays an important role in the functioning of the central nervous system, and especially in the mitochondrial metabolism of fatty acids. Altered carnitine metabolism, abnormal fatty acid metabolism in patients with autism spectrum disorder (ASD) has been documented. ASD is a complex heterogeneous neurodevelopmental condition that is usually diagnosed in early childhood. Patients with ASD require careful classification as this heterogeneous clinical category may include patients with an intellectual disability or high functioning, epilepsy, language impairments, or associated Mendelian genetic conditions. L-carnitine participates in the long-chain oxidation of fatty acids in the brain, stimulates acetylcholine synthesis (donor of the acyl groups), stimulates expression of growth-associated protein-43, prevents cell apoptosis and neuron damage and stimulates neurotransmission. Determination of L-carnitine in serum/plasma and analysis of acylcarnitines in a dried blood spot may be useful in ASD diagnosis and treatment. Changes in the acylcarnitine profiles may indicate potential mitochondrial dysfunctions and abnormal fatty acid metabolism in ASD children. L-carnitine deficiency or deregulation of L-carnitine metabolism in ASD is accompanied by disturbances of other metabolic pathways, e.g., Krebs cycle, the activity of respiratory chain complexes, indicative of mitochondrial dysfunction. Supplementation of L-carnitine may be beneficial to alleviate behavioral and cognitive symptoms in ASD patients.
Collapse
|
5
|
Latham LE, Wang C, Patterson TA, Slikker W, Liu F. Neuroprotective Effects of Carnitine and Its Potential Application to Ameliorate Neurotoxicity. Chem Res Toxicol 2021; 34:1208-1222. [PMID: 33570912 DOI: 10.1021/acs.chemrestox.0c00479] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Carnitine is an essential metabolite that is absorbed from the diet and synthesized in the kidney, liver, and brain. It ferries fatty acids across the mitochondrial membrane to undergo β-oxidation. Carnitine has been studied as a therapy or protective agent for many neurological diseases and neurotoxicity (e.g., prolonged anesthetic exposure-induced developmental neurotoxicity in preclinical models). Preclinical and clinical data support the notion that carnitine or acetyl carnitine may improve a patient's quality of life through increased mitochondrial respiration, release of neurotransmitters, and global gene expression changes, showing the potential of carnitine beyond its approved use to treat primary and secondary carnitine deficiency. In this review, we summarize the beneficial effects of carnitine or acetyl carnitine on the central nervous system, highlighting protective effects against neurotoxicity-induced damage caused by various chemicals and encouraging a thorough evaluation of carnitine use as a therapy for patients suffering from neurotoxicant exposure.
Collapse
Affiliation(s)
- Leah E Latham
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, Arkansas 72079, United States
| | - Cheng Wang
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, Arkansas 72079, United States
| | - Tucker A Patterson
- Office of Director, National Center for Toxicological Research/FDA, Jefferson, Arkansas 72079, United States
| | - William Slikker
- Office of Director, National Center for Toxicological Research/FDA, Jefferson, Arkansas 72079, United States
| | - Fang Liu
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, Arkansas 72079, United States
| |
Collapse
|
6
|
Grzadzinski R, Janvier D, Kim SH. Recent Developments in Treatment Outcome Measures for Young Children With Autism Spectrum Disorder (ASD). Semin Pediatr Neurol 2020; 34:100806. [PMID: 32446440 PMCID: PMC7248125 DOI: 10.1016/j.spen.2020.100806] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Significant advancements have been made in early intervention programs for children with Autism spectrum disorder (ASD). However, measuring treatment response for children with ASD is difficult due to the heterogeneity of changes in symptoms, which can be subtle, especially over a short period of time. Here we outline the challenge of evaluating treatment response with currently available measures as well as newly developed or refined measures that may be useful in clinical trials for young children with ASD. Continued development of treatment outcome measures will help the field identify and compare efficacious interventions and tailor treatments for children with ASD.
Collapse
Affiliation(s)
- Rebecca Grzadzinski
- University of North Carolina, Carolina Institute for Developmental Disabilities, Chapel Hill, NC.
| | - Denisse Janvier
- Center for Autism and the Developing Brain, Weill Cornell Medical College, New York-Presbyterian Hospital, White Plains, NY
| | - So Hyun Kim
- Center for Autism and the Developing Brain, Weill Cornell Medical College, New York-Presbyterian Hospital, White Plains, NY
| |
Collapse
|
7
|
Durazzo A, Lucarini M, Nazhand A, Souto SB, Silva AM, Severino P, Souto EB, Santini A. The Nutraceutical Value of Carnitine and Its Use in Dietary Supplements. Molecules 2020; 25:E2127. [PMID: 32370025 PMCID: PMC7249051 DOI: 10.3390/molecules25092127] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 04/26/2020] [Accepted: 04/28/2020] [Indexed: 02/06/2023] Open
Abstract
Carnitine can be considered a conditionally essential nutrient for its importance in human physiology. This paper provides an updated picture of the main features of carnitine outlining its interest and possible use. Particular attention has been addressed to its beneficial properties, exploiting carnitine's properties and possible use by considering the main in vitro, in animal, and human studies. Moreover, the main aspects of carnitine-based dietary supplements have been indicated and defined with reference to their possible beneficial health properties.
Collapse
Affiliation(s)
- Alessandra Durazzo
- CREA-Research Centre for Food and Nutrition, Via Ardeatina 546, 00178 Rome, Italy;
| | - Massimo Lucarini
- CREA-Research Centre for Food and Nutrition, Via Ardeatina 546, 00178 Rome, Italy;
| | - Amirhossein Nazhand
- Department of Biotechnology, Sari Agriculture Science and Natural Resource University, 9th km of Farah Abad Road, Sari 48181 68984, Mazandaran, Iran;
| | - Selma B. Souto
- Department of Endocrinology of Hospital São João, Alameda Prof. Hernâni Monteiro, 4200-319 Porto, Portugal;
| | - Amélia M. Silva
- Department of Biology and Environment, University of Trás-os-Montes e Alto Douro (UTAD), Quinta de Prados, P-5001-801 Vila Real, Portugal;
- Centre for Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes e Alto Douro (UTAD), P-5001-801 Vila Real, Portugal
| | - Patrícia Severino
- Industrial Biotechnology Program, University of Tiradentes (UNIT), Av. Murilo Dantas 300, Aracaju 49032-490, Brazil;
- Tiradentes Institute, 150 Mt Vernon St, Dorchester, MA 02125, USA
- Laboratory of Nanotechnology and Nanomedicine (LNMED), Institute of Technology and Research (ITP), Av. Murilo Dantas, 300, Aracaju 49010-390, Brazil
| | - Eliana B. Souto
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal;
- CEB—Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Antonello Santini
- Department of Pharmacy, University of Napoli Federico II, Via. D. Montesano 49, 80131 Napoli, Italy
| |
Collapse
|
8
|
Frye RE, Vassall S, Kaur G, Lewis C, Karim M, Rossignol D. Emerging biomarkers in autism spectrum disorder: a systematic review. ANNALS OF TRANSLATIONAL MEDICINE 2019; 7:792. [PMID: 32042808 DOI: 10.21037/atm.2019.11.53] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Autism spectrum disorder (ASD) affects approximately 2% of children in the United States (US) yet its etiology is unclear and effective treatments are lacking. Therapeutic interventions are most effective if started early in life, yet diagnosis often remains delayed, partly because the diagnosis of ASD is based on identifying abnormal behaviors that may not emerge until the disorder is well established. Biomarkers that identify children at risk during the pre-symptomatic period, assist with early diagnosis, confirm behavioral observations, stratify patients into subgroups, and predict therapeutic response would be a great advance. Here we underwent a systematic review of the literature on ASD to identify promising biomarkers and rated the biomarkers in regards to a Level of Evidence and Grade of Recommendation using the Oxford Centre for Evidence-Based Medicine scale. Biomarkers identified by our review included physiological biomarkers that identify neuroimmune and metabolic abnormalities, neurological biomarkers including abnormalities in brain structure, function and neurophysiology, subtle behavioral biomarkers including atypical development of visual attention, genetic biomarkers and gastrointestinal biomarkers. Biomarkers of ASD may be found prior to birth and after diagnosis and some may predict response to specific treatments. Many promising biomarkers have been developed for ASD. However, many biomarkers are preliminary and need to be validated and their role in the diagnosis and treatment of ASD needs to be defined. It is likely that biomarkers will need to be combined to be effective to identify ASD early and guide treatment.
Collapse
Affiliation(s)
- Richard E Frye
- Barrow Neurological Institute at Phoenix Children's Hospital, Phoenix, AZ, USA.,Deparment of Child Health, University of Arizona College of Medicine, Phoenix, AZ, USA
| | - Sarah Vassall
- Barrow Neurological Institute at Phoenix Children's Hospital, Phoenix, AZ, USA
| | - Gurjot Kaur
- Barrow Neurological Institute at Phoenix Children's Hospital, Phoenix, AZ, USA
| | - Christina Lewis
- Barrow Neurological Institute at Phoenix Children's Hospital, Phoenix, AZ, USA
| | - Mohammand Karim
- Barrow Neurological Institute at Phoenix Children's Hospital, Phoenix, AZ, USA.,Deparment of Child Health, University of Arizona College of Medicine, Phoenix, AZ, USA
| | | |
Collapse
|
9
|
Malaguarnera M, Cauli O. Effects of l-Carnitine in Patients with Autism Spectrum Disorders: Review of Clinical Studies. Molecules 2019; 24:molecules24234262. [PMID: 31766743 PMCID: PMC6930613 DOI: 10.3390/molecules24234262] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 11/21/2019] [Accepted: 11/21/2019] [Indexed: 12/27/2022] Open
Abstract
Carnitine is an amino acid derivative, which plays several important roles in human physiology, in the central nervous system, and for mitochondrial metabolism, in particular. Altered carnitine metabolic routes have been associated with a subgroup of patients with autism spectrum disorders (ASD) and could add to the pathophysiology associated with these disorders. We review the current evidence about the clinical effects of carnitine administration in ASD in both non-syndromic forms and ASD associated with genetic disorders. Two randomized clinical trials and one open-label prospective trial suggest that carnitine administration could be useful for treating symptoms in non-syndromic ASD. The effect of carnitine administration in ASD associated with genetic disorders is not conclusive because of a lack of clinical trials and objectives in ASD evaluation, but beneficial effects have also been reported for other comorbid disorders, such as intellectual disability and muscular strength. Side effects observed with a dose of 200 mg/kg/day consisted of gastro-intestinal symptoms and a strong, heavy skin odor. Doses of about 50–100 mg/kg/day are generally well tolerated. Further clinical trials with the identification of the subgroup of ASD patients that would benefit from carnitine administration are warranted.
Collapse
Affiliation(s)
- Michele Malaguarnera
- Research Center “The Great Senescence”, University of Catania, 95100 Catania, Italy;
- Department of Nursing, University of Valencia, 46010 Valencia, Spain
| | - Omar Cauli
- Department of Nursing, University of Valencia, 46010 Valencia, Spain
- Frailty and Cognitive Impairment Group (FROG), University of Valencia, 46010 Valencia, Spain
- Correspondence:
| |
Collapse
|
10
|
Bankaitis VA, Xie Z. The neural stem cell/carnitine malnutrition hypothesis: new prospects for effective reduction of autism risk? J Biol Chem 2019; 294:19424-19435. [PMID: 31699893 DOI: 10.1074/jbc.aw119.008137] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Autism spectrum disorders (ASDs) are developmental neuropsychiatric disorders with heterogeneous etiologies. As the incidence of these disorders is rising, such disorders represent a major human health problem with escalating social cost. Although recent years witnessed advances in our understanding of the genetic basis of some dysmorphic ASDs, little progress has been made in translating the improved understanding into effective strategies for ASD management or minimization of general ASD risk. Here we explore the idea, described in terms of the neural stem cell (NSC)/carnitine malnutrition hypothesis, that an unappreciated risk factor for ASD is diminished capacity for carnitine-dependent long-chain fatty acid β-oxidation in neural stem cells of the developing mammalian brain. The basic premise is that fetal carnitine status is a significant metabolic component in determining NSC vulnerability to derangements in their self-renewal program and, therefore, to fetal ASD risk. As fetal carnitine status exhibits a genetic component that relates to de novo carnitine biosynthesis and is sensitive to environmental and behavioral factors that affect maternal circulating carnitine levels, to which the fetus is exposed, we propose that reduced carnitine availability during gestation is a common risk factor that lurks beneath the genetically complex ASD horizon. One major prediction of the NSC/carnitine malnutrition hypothesis is that a significant component of ASD risk might be effectively managed from a public policy perspective by implementing a carnitine surveillance and dietary supplementation strategy for women planning pregnancies and for women in their first trimester of pregnancy. We argue that this prediction deserves serious clinical interrogation.
Collapse
Affiliation(s)
- Vytas A Bankaitis
- Department of Molecular and Cellular Medicine, Texas A&M University Health Science Center, College Station, Texas 77843-1114 .,Department of Biochemistry and Biophysics, Texas A&M University Health Science Center, College Station, Texas 77843-1114.,Department of Chemistry, Texas A&M University Health Science Center, College Station, Texas 77843-1114
| | - Zhigang Xie
- Department of Molecular and Cellular Medicine, Texas A&M University Health Science Center, College Station, Texas 77843-1114
| |
Collapse
|