1
|
Koch J, Broeks MH, Gautschi M, Jans J, Laemmle A. Inborn errors of the malate aspartate shuttle - Update on patients and cellular models. Mol Genet Metab 2024; 142:108520. [PMID: 38945121 DOI: 10.1016/j.ymgme.2024.108520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 05/30/2024] [Accepted: 06/21/2024] [Indexed: 07/02/2024]
Abstract
The malate aspartate shuttle (MAS) plays a pivotal role in transporting cytosolic reducing equivalents - electrons - into the mitochondria for energy conversion at the electron transport chain (ETC) and in the process of oxidative phosphorylation. The MAS consists of two pairs of cytosolic and mitochondrial isoenzymes (malate dehydrogenases 1 and 2; and glutamate oxaloacetate transaminases 1 and 2) and two transporters (malate-2-oxoglutarate carrier and aspartate glutamate carrier (AGC), the latter of which has two tissue-dependent isoforms AGC1 and AGC2). While the inner mitochondrial membrane is impermeable to NADH, the MAS forms one of the main routes for mitochondrial electron uptake by promoting uptake of malate. Inherited bi-allelic pathogenic variants in five of the seven components of the MAS have been described hitherto and cause a wide spectrum of symptoms including early-onset epileptic encephalopathy. This review provides an overview of reported patients suffering from MAS deficiencies. In addition, we give an overview of diagnostic procedures and research performed on patient-derived cellular models and tissues. Current cellular models are briefly discussed and novel ways to achieve a better understanding of MAS deficiencies are highlighted.
Collapse
Affiliation(s)
- Jasmine Koch
- Division of Pediatric Endocrinology, Diabetology and Metabolism, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Melissa H Broeks
- Department of Genetics, Section Metabolic Diagnostics, University Medical Center Utrecht, Lundlaan 6, 3584 EA Utrecht, the Netherlands
| | - Matthias Gautschi
- Division of Pediatric Endocrinology, Diabetology and Metabolism, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; University Institute of Clinical Chemistry, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Judith Jans
- Department of Genetics, Section Metabolic Diagnostics, University Medical Center Utrecht, Lundlaan 6, 3584 EA Utrecht, the Netherlands
| | - Alexander Laemmle
- Division of Pediatric Endocrinology, Diabetology and Metabolism, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland; University Institute of Clinical Chemistry, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.
| |
Collapse
|
2
|
Karachaliou CE, Livaniou E. Biotin Homeostasis and Human Disorders: Recent Findings and Perspectives. Int J Mol Sci 2024; 25:6578. [PMID: 38928282 PMCID: PMC11203980 DOI: 10.3390/ijms25126578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2024] [Revised: 06/11/2024] [Accepted: 06/11/2024] [Indexed: 06/28/2024] Open
Abstract
Biotin (vitamin B7, or vitamin H) is a water-soluble B-vitamin that functions as a cofactor for carboxylases, i.e., enzymes involved in the cellular metabolism of fatty acids and amino acids and in gluconeogenesis; moreover, as reported, biotin may be involved in gene regulation. Biotin is not synthesized by human cells, but it is found in food and is also produced by intestinal bacteria. Biotin status/homeostasis in human individuals depends on several factors, including efficiency/deficiency of the enzymes involved in biotin recycling within the human organism (biotinidase, holocarboxylase synthetase), and/or effectiveness of intestinal uptake, which is mainly accomplished through the sodium-dependent multivitamin transporter. In the last years, administration of biotin at high/"pharmacological" doses has been proposed to treat specific defects/deficiencies and human disorders, exhibiting mainly neurological and/or dermatological symptoms and including biotinidase deficiency, holocarboxylase synthetase deficiency, and biotin-thiamine-responsive basal ganglia disease. On the other hand, according to warnings of the Food and Drug Administration, USA, high biotin levels can affect clinical biotin-(strept)avidin assays and thus lead to false results during quantification of critical biomarkers. In this review article, recent findings/advancements that may offer new insight in the abovementioned research fields concerning biotin will be presented and briefly discussed.
Collapse
Affiliation(s)
| | - Evangelia Livaniou
- Immunopeptide Chemistry Lab, Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, National Centre for Scientific Research “Demokritos”, P.O. Box 60037, 153 10 Agia Paraskevi, Greece;
| |
Collapse
|
3
|
LeMaster C, Schwendinger-Schreck C, Ge B, Cheung WA, McLennan R, Johnston JJ, Pastinen T, Smail C. Mapping structural variants to rare disease genes using long-read whole genome sequencing and trait-relevant polygenic scores. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.03.15.24304216. [PMID: 38562793 PMCID: PMC10984062 DOI: 10.1101/2024.03.15.24304216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Recent studies have revealed the pervasive landscape of rare structural variants (rSVs) present in human genomes. rSVs can have extreme effects on the expression of proximal genes and, in a rare disease context, have been implicated in patient cases where no diagnostic single nucleotide variant (SNV) was found. Approaches for integrating rSVs to date have focused on targeted approaches in known Mendelian rare disease genes. This approach is intractable for rare diseases with many causal loci or patients with complex, multi-phenotype syndromes. We hypothesized that integrating trait-relevant polygenic scores (PGS) would provide a substantial reduction in the number of candidate disease genes in which to assess rSV effects. We further implemented a method for ranking PGS genes to define a set of core/key genes where a rSV has the potential to exert relatively larger effects on disease risk. Among a subset of patients enrolled in the Genomic Answers for Kids (GA4K) rare disease program (N=497), we used PacBio HiFi long-read whole genome sequencing (lrWGS) to identify rSVs intersecting genes in trait-relevant PGSs. Illustrating our approach in Autism (N=54 cases), we identified 22, 019 deletions, 2,041 duplications, 87,826 insertions, and 214 inversions overlapping putative core/key PGS genes. Additionally, by integrating genomic constraint annotations from gnomAD, we observed that rare duplications overlapping putative core/key PGS genes were frequently in higher constraint regions compared to controls (P = 1×10-03). This difference was not observed in the lowest-ranked gene set (P = 0.15). Overall, our study provides a framework for the annotation of long-read rSVs from lrWGS data and prioritization of disease-linked genomic regions for downstream functional validation of rSV impacts. To enable reuse by other researchers, we have made SV allele frequencies and gene associations freely available.
Collapse
Affiliation(s)
- Cas LeMaster
- Genomic Medicine Center, Children’s Mercy Research Institute and Children’s Mercy Kansas City, Kansas City, MO, USA
| | - Carl Schwendinger-Schreck
- Genomic Medicine Center, Children’s Mercy Research Institute and Children’s Mercy Kansas City, Kansas City, MO, USA
| | - Bing Ge
- McGill University, Montreal, Quebec, Canada
| | - Warren A. Cheung
- Genomic Medicine Center, Children’s Mercy Research Institute and Children’s Mercy Kansas City, Kansas City, MO, USA
| | - Rebecca McLennan
- Genomic Medicine Center, Children’s Mercy Research Institute and Children’s Mercy Kansas City, Kansas City, MO, USA
| | - Jeffrey J. Johnston
- Genomic Medicine Center, Children’s Mercy Research Institute and Children’s Mercy Kansas City, Kansas City, MO, USA
| | - Tomi Pastinen
- Genomic Medicine Center, Children’s Mercy Research Institute and Children’s Mercy Kansas City, Kansas City, MO, USA
| | - Craig Smail
- Genomic Medicine Center, Children’s Mercy Research Institute and Children’s Mercy Kansas City, Kansas City, MO, USA
| |
Collapse
|
4
|
Wang YY, Zhou YQ, Luo LJ, Wang CJ, Shen N, Li H, Wang JW. Ketogenic diet therapy in children with epilepsy caused by SLC2A1 mutations: a single-center single-arm retrospective study. World J Pediatr 2024; 20:517-524. [PMID: 36303089 DOI: 10.1007/s12519-022-00620-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 09/05/2022] [Indexed: 10/31/2022]
Abstract
BACKGROUND This retrospective study assessed the efficacy and safety of ketogenic diet therapies in children with epilepsy caused by SLC2A1 genetic mutations and glucose transporter type 1 deficiency syndrome. METHODS Pediatric patients with epilepsy symptoms admitted to our medical center between January 2017 and October 2021 were included if they presented with an SLC2A1 genetic mutation on whole-exome sequencing. We analyzed the patients' convulsions and treatment with antiepileptic drugs. The patients were followed up at different time periods after ketogenic diet therapies. RESULTS Six patients with SLC2A1 mutations were included in this study. The patients had seizures of different types and frequencies, and they took antiepileptic drugs to relieve their symptoms. They were then treated with a ketogenic diet for at least four months. We analyzed epilepsy control rates at 1, 2, 3, 6, and 12 months after ketogenic diet treatment. All patients were seizure-free within a month of receiving the diet therapy. All patients were followed up for six months, three were followed up for 12 months after the treatment, and there was no recurrence of epilepsy during this period. After antiepileptic drug withdrawal, none of the patients experienced seizure relapse when receiving ketogenic diet treatment alone. No severe adverse events occurred during the therapy. CONCLUSIONS Ketogenic diet therapy is very effective and safe for the treatment of epilepsy caused by SLC2A1 mutations. Therefore, patients with glucose transporter type 1 deficiency syndrome caused by SLC2A1 mutations should begin ketogenic diet treatment as soon as possible.
Collapse
Affiliation(s)
- Ying-Yan Wang
- Department of Neurology, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yun-Qing Zhou
- Department of Neurology, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Li-Juan Luo
- Department of Infectious Diseases, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Cui-Jin Wang
- Department of Neurology, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Nan Shen
- Department of Infectious Diseases, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Hao Li
- Department of Neurology, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
- Clinical Research Ward, Clinical Research Center, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
| | - Ji-Wen Wang
- Department of Neurology, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
| |
Collapse
|
5
|
Tu G, Fu T, Zheng G, Xu B, Gou R, Luo D, Wang P, Xue W. Computational Chemistry in Structure-Based Solute Carrier Transporter Drug Design: Recent Advances and Future Perspectives. J Chem Inf Model 2024; 64:1433-1455. [PMID: 38294194 DOI: 10.1021/acs.jcim.3c01736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
Solute carrier transporters (SLCs) are a class of important transmembrane proteins that are involved in the transportation of diverse solute ions and small molecules into cells. There are approximately 450 SLCs within the human body, and more than a quarter of them are emerging as attractive therapeutic targets for multiple complex diseases, e.g., depression, cancer, and diabetes. However, only 44 unique transporters (∼9.8% of the SLC superfamily) with 3D structures and specific binding sites have been reported. To design innovative and effective drugs targeting diverse SLCs, there are a number of obstacles that need to be overcome. However, computational chemistry, including physics-based molecular modeling and machine learning- and deep learning-based artificial intelligence (AI), provides an alternative and complementary way to the classical drug discovery approach. Here, we present a comprehensive overview on recent advances and existing challenges of the computational techniques in structure-based drug design of SLCs from three main aspects: (i) characterizing multiple conformations of the proteins during the functional process of transportation, (ii) identifying druggability sites especially the cryptic allosteric ones on the transporters for substrates and drugs binding, and (iii) discovering diverse small molecules or synthetic protein binders targeting the binding sites. This work is expected to provide guidelines for a deep understanding of the structure and function of the SLC superfamily to facilitate rational design of novel modulators of the transporters with the aid of state-of-the-art computational chemistry technologies including artificial intelligence.
Collapse
Affiliation(s)
- Gao Tu
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Tingting Fu
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | | | - Binbin Xu
- Chengdu Sintanovo Biotechnology Co., Ltd., Chengdu 610200, China
| | - Rongpei Gou
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Ding Luo
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| | - Panpan Wang
- College of Chemistry and Pharmaceutical Engineering, Huanghuai University, Zhumadian 463000, China
| | - Weiwei Xue
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, China
| |
Collapse
|
6
|
Mai AS, Yau CE, Tseng FS, Foo QXJ, Wang DQ, Tan EK. Linking autism spectrum disorders and parkinsonism: clinical and genetic association. Ann Clin Transl Neurol 2023; 10:484-496. [PMID: 36738194 PMCID: PMC10109258 DOI: 10.1002/acn3.51736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 01/03/2023] [Accepted: 01/09/2023] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Autism spectrum disorders (ASD) comprise many complex and clinically distinct neurodevelopmental conditions, with increasing evidence linking them to parkinsonism. METHODS We searched Medline and Embase from inception to 21 March 2022 and reviewed the bibliographies of relevant articles. Studies were screened and reviewed comprehensively by two independent authors. RESULTS Of 863 references from our search, we included eight clinical studies, nine genetic studies, and five case reports. Regardless of age group, Parkinson's disease (PD) and parkinsonian syndromes were more frequently observed in patients with ASD, though the evidence for increased rates of parkinsonism is less clear for children and adolescents. Parkinsonian features and hypokinetic behavior were common in Rett syndrome, with prevalence estimates ranging from 40% to 80%. Frequently observed parkinsonian features include bradykinesia, rigidity, hypomimia, and gait freezing. PD gene PARK2 copy number variations appear more frequently in ASD cases than controls. Evidence suggests that RIT2 and CD157/BST1 are implicated in ASD and PD, while the evidence for other PD-related genes (DRD2, GPCR37, the SLC gene family, and SMPD1) is less clear. Rare mutations, such as ATP13A2, CLN3, and WDR45, could result in autistic behavior and concomitant parkinsonism. CONCLUSION The prevalence of parkinsonism in ASD is substantially greater than in the general population or matched controls. Various PD-associated gene loci, especially PARK2, could confer susceptibility to ASD as well. Important future directions include conducting prospective cohort studies to understand how parkinsonian symptoms may progress, genetic studies to reveal relevant gene loci, and pathophysiologic studies to identify potential therapeutic targets.
Collapse
Affiliation(s)
- Aaron Shengting Mai
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Chun En Yau
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Fan Shuen Tseng
- Department of Neurology, Singapore General Hospital Campus, National Neuroscience Institute, Singapore, Singapore
| | - Qi Xuan Joel Foo
- Department of Neurology, Singapore General Hospital Campus, National Neuroscience Institute, Singapore, Singapore
| | - Dennis Qing Wang
- Department of Neurology, Zhujiang Hospital of Southern Medical University, Southern Medical University, Guangzhou, China
| | - Eng-King Tan
- Department of Neurology, Singapore General Hospital Campus, National Neuroscience Institute, Singapore, Singapore.,Neuroscience and Behavioural Disorders, Duke-NUS Medical School, Singapore, Singapore
| |
Collapse
|
7
|
Whitney R, Choi E, Jones KC. The neuroimaging spectrum of SLC13A5 related developmental and epileptic encephalopathy. Seizure 2023; 106:8-13. [PMID: 36701889 DOI: 10.1016/j.seizure.2023.01.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 12/14/2022] [Accepted: 01/18/2023] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND SLC13A5 related developmental and epileptic encephalopathy (DEE) is an autosomal recessive condition characterized by neonatal seizures, fever sensitivity, status epilepticus, developmental delay and tooth anomalies. The neuroimaging spectrum of SLC13A5 related DEE is not fully known. We present a case of SLC13A5 related DEE with distinct neuroimaging findings and review the neuroimaging findings of all published cases of SLC13A5 related DEE. METHODS A retrospective case review and focused review of the literature was completed. RESULTS A 16-month-old male with a clinical phenotype consistent with SLC13A5 related DEE and a previously reported pathogenic variant in SLC13A5, c.655G>A, p.Gly219Arg and a novel likely pathogenic variant in SLC13A5, c.202C>T, p.Pro68Ser was identified. MRI at day 5 of life revealed wide spread punctate white matter lesions (PWMLs) affecting the subcortical white matter, periventricular white matter, splenium of the corpus callosum, posterior limb of the internal capsule, corticospinal tracts, midbrain, pons and medulla, mimicking a metabolic/infectious etiology. MRI at one month showed atrophy and evolution of white matter necrosis. One hundred and five cases of SLC13A5 related DEE were identified. Initial MRI was completed in 62 cases (59%). MRI was normal in 41 cases (66%) and abnormal in 21 (34%). White matter abnormalities were most common (n=15, 71%); PWMLs occurred in 8 cases (38%). CONCLUSION Neuroimaging abnormalities may exist in a third of SLC13A5 related DEE cases. White matter abnormalities such as PWMLs appear most common. It remains unknown why some are susceptible to these lesions and how they affect long-term neurodevelopmental outcomes in SLC13A5 related DEE.
Collapse
Affiliation(s)
- Robyn Whitney
- Division of Neurology, Department of Paediatrics, McMaster University, 1200 Main Street West, Hamilton, ON, Canada.
| | - Elaine Choi
- Division of Neurology, Department of Paediatrics, McMaster University, 1200 Main Street West, Hamilton, ON, Canada
| | - Kevin C Jones
- Division of Neurology, Department of Paediatrics, McMaster University, 1200 Main Street West, Hamilton, ON, Canada
| |
Collapse
|
8
|
Alijanpour S, Miryounesi M, Ghafouri-Fard S. The role of excitatory amino acid transporter 2 (EAAT2) in epilepsy and other neurological disorders. Metab Brain Dis 2023; 38:1-16. [PMID: 36173507 DOI: 10.1007/s11011-022-01091-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 09/15/2022] [Indexed: 02/03/2023]
Abstract
Glutamate is the major excitatory neurotransmitter in the central nervous system (CNS). Excitatory amino acid transporters (EAATs) have important roles in the uptake of glutamate and termination of glutamatergic transmission. Up to now, five EAAT isoforms (EAAT1-5) have been identified in mammals. The main focus of this review is EAAT2. This protein has an important role in the pathoetiology of epilepsy. De novo dominant mutations, as well as inherited recessive mutation in this gene, have been associated with epilepsy. Moreover, dysregulation of this protein is implicated in a range of neurological diseases, namely amyotrophic lateral sclerosis, alzheimer's disease, parkinson's disease, schizophrenia, epilepsy, and autism. In this review, we summarize the role of EAAT2 in epilepsy and other neurological disorders, then provide an overview of the therapeutic modulation of this protein.
Collapse
Affiliation(s)
- Sahar Alijanpour
- Department of Medical Genetics, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Miryounesi
- Department of Medical Genetics, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Soudeh Ghafouri-Fard
- Department of Medical Genetics, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
9
|
Gan Y, Wei Z, Liu C, Li G, Feng Y, Deng Y. Solute carrier transporter disease and developmental and epileptic encephalopathy. Front Neurol 2022; 13:1013903. [PMID: 36419532 PMCID: PMC9676364 DOI: 10.3389/fneur.2022.1013903] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 09/07/2022] [Indexed: 09/14/2023] Open
Abstract
The International League Against Epilepsy officially revised its classification in 2017, which amended "epileptic encephalopathy" to "developmental and epileptic encephalopathy". With the development of genetic testing technology, an increasing number of genes that cause developmental and epileptic encephalopathies are being identified. Among these, solute transporter dysfunction is part of the etiology of developmental and epileptic encephalopathies. Solute carrier transporters play an essential physiological function in the human body, and their dysfunction is associated with various human diseases. Therefore, in-depth studies of developmental and epileptic encephalopathies caused by solute carrier transporter dysfunction can help develop new therapeutic modalities to facilitate the treatment of refractory epilepsy and improve patient prognosis. In this article, the concept of transporter protein disorders is first proposed, and nine developmental and epileptic encephalopathies caused by solute carrier transporter dysfunction are described in detail in terms of pathogenesis, clinical manifestations, ancillary tests, and precise treatment to provide ideas for the precise treatment of epilepsy.
Collapse
Affiliation(s)
- Yajing Gan
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Zihan Wei
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Chao Liu
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Guoyan Li
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Yan Feng
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Yanchun Deng
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
- Xijing Institute of Epilepsy and Encephalopathy, Xi'an, China
| |
Collapse
|
10
|
Krgovic D, Gorenjak M, Rihar N, Opalic I, Stangler Herodez S, Gregoric Kumperscak H, Dovc P, Kokalj Vokac N. Impaired Neurodevelopmental Genes in Slovenian Autistic Children Elucidate the Comorbidity of Autism With Other Developmental Disorders. Front Mol Neurosci 2022; 15:912671. [PMID: 35813072 PMCID: PMC9259896 DOI: 10.3389/fnmol.2022.912671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 05/11/2022] [Indexed: 11/13/2022] Open
Abstract
Autism spectrum disorders (ASD) represent a phenotypically heterogeneous group of patients that strongly intertwine with other neurodevelopmental disorders (NDDs), with genetics playing a significant role in their etiology. Whole exome sequencing (WES) has become predominant in molecular diagnostics for ASD by considerably increasing the diagnostic yield. However, the proportion of undiagnosed patients still remains high due to complex clinical presentation, reduced penetrance, and lack of segregation analysis or clinical information. Thus, reverse phenotyping, where we first identified a possible genetic cause and then determine its clinical relevance, has been shown to be a more efficient approach. WES was performed on 147 Slovenian pediatric patients with suspected ASD. Data analysis was focused on identifying ultrarare or “single event” variants in ASD-associated genes and further expanded to NDD-associated genes. Protein function and gene prioritization were performed on detected clinically relevant variants to determine their role in ASD etiology and phenotype. Reverse phenotyping revealed a pathogenic or likely pathogenic variant in ASD-associated genes in 20.4% of patients, with subsequent segregation analysis indicating that 14 were de novo variants and 1 was presumed compound heterozygous. The diagnostic yield was further increased by 2.7% by the analysis of ultrarare or “single event” variants in all NDD-associated genes. Protein function analysis established that genes in which variants of unknown significance (VUS) were detected were predominantly the cause of intellectual disability (ID), and in most cases, features of ASD as well. Using such an approach, variants in rarely described ASD-associated genes, such as SIN3B, NR4A2, and GRIA1, were detected. By expanding the analysis to include functionally similar NDD genes, variants in KCNK9, GNE, and other genes were identified. These would probably have been missed by classic genotype–phenotype analysis. Our study thus demonstrates that in patients with ASD, analysis of ultrarare or “single event” variants obtained using WES with the inclusion of functionally similar genes and reverse phenotyping obtained a higher diagnostic yield despite limited clinical data. The present study also demonstrates that most of the causative genes in our cohort were involved in the syndromic form of ASD and confirms their comorbidity with other developmental disorders.
Collapse
Affiliation(s)
- Danijela Krgovic
- Laboratory of Medical Genetics, University Medical Centre Maribor, Maribor, Slovenia
- Department of Molecular Biology, Faculty of Medicine, University of Maribor, Maribor, Slovenia
- *Correspondence: Danijela Krgovic,
| | - Mario Gorenjak
- Centre for Human Molecular Genetics, and Pharmacogenomics, Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | - Nika Rihar
- Department of Animal Science, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Iva Opalic
- Laboratory of Medical Genetics, University Medical Centre Maribor, Maribor, Slovenia
| | - Spela Stangler Herodez
- Laboratory of Medical Genetics, University Medical Centre Maribor, Maribor, Slovenia
- Department of Molecular Biology, Faculty of Medicine, University of Maribor, Maribor, Slovenia
| | | | - Peter Dovc
- Department of Animal Science, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Nadja Kokalj Vokac
- Laboratory of Medical Genetics, University Medical Centre Maribor, Maribor, Slovenia
- Department of Molecular Biology, Faculty of Medicine, University of Maribor, Maribor, Slovenia
| |
Collapse
|
11
|
A Historical Review of Brain Drug Delivery. Pharmaceutics 2022; 14:pharmaceutics14061283. [PMID: 35745855 PMCID: PMC9229021 DOI: 10.3390/pharmaceutics14061283] [Citation(s) in RCA: 49] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/01/2022] [Accepted: 06/07/2022] [Indexed: 12/13/2022] Open
Abstract
The history of brain drug delivery is reviewed beginning with the first demonstration, in 1914, that a drug for syphilis, salvarsan, did not enter the brain, due to the presence of a blood-brain barrier (BBB). Owing to restricted transport across the BBB, FDA-approved drugs for the CNS have been generally limited to lipid-soluble small molecules. Drugs that do not cross the BBB can be re-engineered for transport on endogenous BBB carrier-mediated transport and receptor-mediated transport systems, which were identified during the 1970s-1980s. By the 1990s, a multitude of brain drug delivery technologies emerged, including trans-cranial delivery, CSF delivery, BBB disruption, lipid carriers, prodrugs, stem cells, exosomes, nanoparticles, gene therapy, and biologics. The advantages and limitations of each of these brain drug delivery technologies are critically reviewed.
Collapse
|