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Su H, Zhang H, Wu J, Huang L, Zhang M, Xu W, Cao J, Liu W, Liu N, Jiang H, Gu X, Qian K. Fast Label-Free Metabolic Profile Recognition Identifies Phenylketonuria and Subtypes. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2305701. [PMID: 38348590 PMCID: PMC11022714 DOI: 10.1002/advs.202305701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 01/25/2024] [Indexed: 04/18/2024]
Abstract
Phenylketonuria (PKU) is the most common inherited metabolic disease in humans. Clinical screening of newborn heel blood samples for PKU is costly and time-consuming because it requires multiple procedures, like isotope labeling and derivatization, and PKU subtype identification requires an additional urine sample. Delayed diagnosis of PKU, or subtype identification can result in mental disability. Here, plasmonic silver nanoshells are used for laser desorption/ionization mass spectrometry (MS) detection of PKU with label-free assay by recognizing metabolic profile in dried blood spot (DBS) samples. A total of 1100 subjects are recruited and each DBS sample can be processed in seconds. This platform achieves PKU screening with a sensitivity of 0.985 and specificity of 0.995, which is comparable to existing clinical liquid chromatography MS (LC-MS) methods. This method can process 360 samples per hour, compared with the LC-MS method which processes only 30 samples per hour. Moreover, this assay enables precise identification of PKU subtypes without the need for a urine sample. It is demonstrated that this platform enables high-performance and fast, low-cost PKU screening and subtype identification. This approach might be suitable for the detection of other clinically relevant biomarkers in blood or other clinical samples.
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Affiliation(s)
- Haiyang Su
- Henan Key Laboratory of Rare DiseasesEndocrinology and Metabolism CenterThe First Affiliated Hospital, and College of Clinical Medicine of Henan University of Science and TechnologyLuoyang471003P. R. China
- State Key Laboratory of Systems Medicine for CancerSchool of Biomedical EngineeringInstitute of Medical Robotics and Shanghai Academy of Experimental MedicineShanghai Jiao Tong UniversityShanghai200030P. R. China
| | - Huiwen Zhang
- Xinhua HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai200092P. R. China
| | - Jiao Wu
- State Key Laboratory of Systems Medicine for CancerSchool of Biomedical EngineeringInstitute of Medical Robotics and Shanghai Academy of Experimental MedicineShanghai Jiao Tong UniversityShanghai200030P. R. China
| | - Lin Huang
- Country Department of Clinical Laboratory MedicineShanghai Chest HospitalShanghai Jiao Tong UniversityShanghai200030P. R. China
| | - Mengji Zhang
- State Key Laboratory of Systems Medicine for CancerSchool of Biomedical EngineeringInstitute of Medical Robotics and Shanghai Academy of Experimental MedicineShanghai Jiao Tong UniversityShanghai200030P. R. China
| | - Wei Xu
- State Key Laboratory for Oncogenes and Related GenesDivision of CardiologyRenji Hospital, School of Medicine, Shanghai Jiao Tong UniversityShanghai200127P. R. China
| | - Jing Cao
- State Key Laboratory of Systems Medicine for CancerSchool of Biomedical EngineeringInstitute of Medical Robotics and Shanghai Academy of Experimental MedicineShanghai Jiao Tong UniversityShanghai200030P. R. China
| | - Wanshan Liu
- Xinhua HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai200092P. R. China
| | - Ning Liu
- School of Electronics Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai200240P. R. China
| | - Hongwei Jiang
- Henan Key Laboratory of Rare DiseasesEndocrinology and Metabolism CenterThe First Affiliated Hospital, and College of Clinical Medicine of Henan University of Science and TechnologyLuoyang471003P. R. China
| | - Xuefan Gu
- Xinhua HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai200092P. R. China
| | - Kun Qian
- State Key Laboratory of Systems Medicine for CancerSchool of Biomedical EngineeringInstitute of Medical Robotics and Shanghai Academy of Experimental MedicineShanghai Jiao Tong UniversityShanghai200030P. R. China
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Ajami N, Soleimani A, Jafarzadeh‐Esfehani R, Hasanpour M, Rashid Shomali R, Abbaszadegan MR. Mutational landscape of phenylketonuria in Iran. J Cell Mol Med 2023; 27:2457-2466. [PMID: 37525467 PMCID: PMC10468661 DOI: 10.1111/jcmm.17865] [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: 07/27/2022] [Revised: 06/11/2023] [Accepted: 06/28/2023] [Indexed: 08/02/2023] Open
Abstract
To date more than 1000 different variants in the PAH gene have been identified in patients with phenylketonuria (PKU). In Iran, several studies have been performed to investigate the genetics bases of the PKU in different parts of the country. In this study, we have analysed and present an update of the mutational landscape of the PAH gene as well as the population genetics and frequencies of detected variants for each cohort. Published articles on PKU mutations in Iran were identified through a comprehensive PubMed, Google Scholar, Web of Science (ISI), SCOPUS, Elsevier, Wiley Online Library and SID literature search using the terms: "phenylketonuria", "hyperphenylalaninemia", and "PKU" in combination with "Iran", "Iranian population", "mutation analysis", and "Molecular genetics". Among the literature-related to genetics of PKU, 18 studies were on the PKU mutations. According to these studies, in different populations of Iran 1497 patients were included for mutation detection that resulted in detection of 129 different mutations. Results of genetic analysis of the different cohorts of Iranian PKU patients show that the most prevalent mutation in Iran is the pathogenic splice variant c.1066-11G > A, occurring in 19.54% of alleles in the cohort. Four other common mutations were p.Arg261Gln, p.Pro281Leu, c.168 + 5G > C and p.Arg243Ter (8.18%, 6.45%, 5.88% and 3.7%, respectively). One notable feature of the studied populations is its high rate of consanguineous marriages. Considering this feature, determining the prevalent PKU mutations could be advantageous for designing screening and diagnostic panels in Iran.
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Affiliation(s)
- Naser Ajami
- Department of Medical Genetics and Molecular Medicine, School of MedicineMashhad University of Medical SciencesMashhadIran
- Medical Genetics Research Center, School of MedicineMashhad University of Medical SciencesMashhadIran
| | - Anvar Soleimani
- Department of Medical Microbiology, College of Health SciencesCihan University‐ SulaimaniyaSulaimaniyaIraq
| | - Reza Jafarzadeh‐Esfehani
- Blood Borne Infections Research Center, Academic Center for EducationCulture and Research (ACECR)‐ Khorasan RazaviMashhadIran
| | - Mojtaba Hasanpour
- Department of Biology, Faculty of SciencesUniversity of GuilanRashtIran
| | - Romina Rashid Shomali
- Reproductive Health Research Center, Department of Obstetrics and Gynecology, Alzahra HospitalGuilan University of Medical SciencesRashtIran
| | - Mohammad Reza Abbaszadegan
- Department of Medical Genetics and Molecular Medicine, School of MedicineMashhad University of Medical SciencesMashhadIran
- Immunology Research CenterMashhad University of Medical SciencesMashhadIran
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Wang L, Gao J, Cao X, Du J, Cao L, Nie Z, Xu G, Dong Z. Integrated Analysis of Transcriptomics and Metabolomics Unveil the Novel Insight of One-Year-Old Precocious Mechanism in the Chinese Mitten Crab, Eriocheir sinensis. Int J Mol Sci 2023; 24:11171. [PMID: 37446357 DOI: 10.3390/ijms241311171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 06/29/2023] [Accepted: 07/03/2023] [Indexed: 07/15/2023] Open
Abstract
Eriocheir sinensis is traditionally a native high-value crab that is widely distributed in eastern Asia, and the precocity is considered the bottleneck problem affecting the development of the industry. The precocious E. sinensis is defined as a crab that reaches complete sexual maturation during the first year of its lifespan rather than as normally in the second year. However, the exact regulatory mechanisms underlying the precocity are still unclear to date. This study is the first to explore the mechanism of precocity with transcriptome-metabolome association analysis between the precocious and normal sexually mature E. sinensis. Our results indicated that the phenylalanine metabolism (map00360) and neuroactive ligand-receptor interaction (map04080) pathways play an important role in the precocity in the ovary of E. sinensis. In map00360, the predicted aromatic-L-amino-acid decarboxylase and 4-hydroxyphenylpyruvate dioxygenase isoform X1 genes and the phenethylamine, phenylethyl alcohol, trans-2-hydroxycinnamate, and L-tyrosine metabolites were all down-regulated in the ovary of the precocious E. sinensis. The map04080 was the common KEGG pathway in the ovary and hepatopancreas between the precocious and normal crab. In the ovary, the predicted growth hormone secretagogue receptor type 1 gene was up-regulated, and the L-glutamate metabolite was down-regulated in the precocious E. sinensis. In the hepatopancreas, the predicted forkhead box protein I2 gene and taurine metabolite were up-regulated and the the L-glutamate metabolite was down-regulated in the precocious crab. There was no common pathway in the testis. Numerous common pathways in the hepatopancreas between male precocious and normal crab were identified. The specific amino acids, fatty acids and flavorful nucleotide (inosine monophosphate (MP), cytidine MP, adenosine MP, uridine MP, and guanosine MP) contents in the hepatopancreas and gonads further confirmed the above omics results. Our results suggest that the phenylalanine metabolism may affect the ovarian development by changing the contents of the neurotransmitter and tyrosine. The neuroactive ligand-receptor interaction pathway may affect the growth by changing the expressions of related genes and affect the umami taste of the gonads and hepatopancreas through the differences of L-glutamate metabolite in the precocious E. sinensis. The results provided valuable and novel insights on the precocious mechanism and may have a significant impact on the development of the E. sinensis aquaculture industry.
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Affiliation(s)
- Lanmei Wang
- Key Laboratory of Freshwater, Fisheries and Germplasm Resources Utilization, Freshwater Fisheries Research Centre of Chinese Academy of Fishery Sciences, Ministry of Agriculture and Rural Affairs, Wuxi 214081, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China
| | - Jiancao Gao
- Key Laboratory of Freshwater, Fisheries and Germplasm Resources Utilization, Freshwater Fisheries Research Centre of Chinese Academy of Fishery Sciences, Ministry of Agriculture and Rural Affairs, Wuxi 214081, China
| | - Xi Cao
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Jinliang Du
- Key Laboratory of Freshwater, Fisheries and Germplasm Resources Utilization, Freshwater Fisheries Research Centre of Chinese Academy of Fishery Sciences, Ministry of Agriculture and Rural Affairs, Wuxi 214081, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China
| | - Liping Cao
- Key Laboratory of Freshwater, Fisheries and Germplasm Resources Utilization, Freshwater Fisheries Research Centre of Chinese Academy of Fishery Sciences, Ministry of Agriculture and Rural Affairs, Wuxi 214081, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China
| | - Zhijuan Nie
- Key Laboratory of Freshwater, Fisheries and Germplasm Resources Utilization, Freshwater Fisheries Research Centre of Chinese Academy of Fishery Sciences, Ministry of Agriculture and Rural Affairs, Wuxi 214081, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China
| | - Gangchun Xu
- Key Laboratory of Freshwater, Fisheries and Germplasm Resources Utilization, Freshwater Fisheries Research Centre of Chinese Academy of Fishery Sciences, Ministry of Agriculture and Rural Affairs, Wuxi 214081, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
| | - Zaijie Dong
- Key Laboratory of Freshwater, Fisheries and Germplasm Resources Utilization, Freshwater Fisheries Research Centre of Chinese Academy of Fishery Sciences, Ministry of Agriculture and Rural Affairs, Wuxi 214081, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China
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Bingöl AC, Bingöl M, Pandis N, Stolz S, Beblo S, Jost-Brinkmann PG, Mönch E, Bartzela T. Dietary and metabolic effects on the oral status of patients with phenylketonuria: a nation-based cross-sectional study. Clin Oral Investig 2023; 27:1981-1991. [PMID: 36805804 PMCID: PMC9939867 DOI: 10.1007/s00784-022-04827-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 12/06/2022] [Indexed: 02/23/2023]
Abstract
OBJECTIVES The aim of this study was to compare the prevalence of oral diseases (caries, periodontal disease, enamel defects) between patients with phenylketonuria (PKU), their siblings, and a matched control group. MATERIALS AND METHODS A total of 109 patients with PKU, 14 siblings of PKU patients, and 100 healthy individuals aged 6 to 68 years were recruited. All participants completed a questionnaire based on their health status. The patients' decayed/missing/filled teeth index (dmft/DMFT), gingival bleeding index (GBI), plaque control record (PCR), periodontal screening and recording index (PSR), and developmental enamel defects index (DDE) were recorded. Descriptive statistics and regression modeling were used to examine potential associations between the exposure and the outcomes of interest. RESULTS Patients with PKU had 1.6 times more caries (95% confidence interval (CI) 1.22 to 2.20; p = 0.001), seven times more enamel defects (95% CI 3.94 to 14.21; p < 0.001), and four times higher PSR values (95% CI 2.26 to 7.15; p < 0.001) than the control group. The siblings had significantly fewer enamel defects but no significant differences in caries and periodontal parameters compared to the PKU patients. CONCLUSIONS The results showed a higher risk for the development of caries, periodontitis, and enamel defects in PKU patients. CLINICAL RELEVANCE Implementation of preventive measures and regular dental care is necessary for patients with PKU.
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Affiliation(s)
- Anne Carolin Bingöl
- Department of Orthodontics and Dentofacial Orthopedics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität Zu Berlin, Institute for Oral Health Sciences, Aßmannshauser Str. 4-6, 14197, Berlin, Germany
| | - Memduh Bingöl
- Department of Orthodontics and Dentofacial Orthopedics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität Zu Berlin, Institute for Oral Health Sciences, Aßmannshauser Str. 4-6, 14197, Berlin, Germany
| | - Nikolaos Pandis
- Department of Orthodontics and Dentofacial Orthopedics, Dental School/Medical Faculty, University of Bern, Freiburgstr. 7, 3010, Bern, Switzerland
| | - Simone Stolz
- Department of Pediatric and Adolescent Medicine, Carl-Thiem-Klinikum Cottbus, Thiemstr. 111, 03048, Cottbus, Germany
| | - Skadi Beblo
- Department of Women and Child Health, Centre for Pediatric Research Leipzig, Hospital for Children and Adolescents, University of Leipzig, Liebigstr. 20a, Haus 6, 04103, Leipzig, Germany
| | - Paul-Georg Jost-Brinkmann
- Department of Orthodontics and Dentofacial Orthopedics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität Zu Berlin, Institute for Oral Health Sciences, Aßmannshauser Str. 4-6, 14197, Berlin, Germany
| | - Eberhard Mönch
- Interdisciplinary Metabolism Centre, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität Zu Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Theodosia Bartzela
- Department of Orthodontics and Dentofacial Orthopedics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität Zu Berlin, Institute for Oral Health Sciences, Aßmannshauser Str. 4-6, 14197, Berlin, Germany.
- Department of Orthodontics, Technische Universität Dresden, Fetscherstraße 74, 01307, Dresden, Germany.
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Expression of phenylalanine ammonia lyase as an intracellularly free and extracellularly cell surface-immobilized enzyme on a gut microbe as a live biotherapeutic for phenylketonuria. SCIENCE CHINA. LIFE SCIENCES 2023; 66:127-136. [PMID: 35907113 PMCID: PMC9362719 DOI: 10.1007/s11427-021-2137-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 06/02/2022] [Indexed: 02/04/2023]
Abstract
Phenylketonuria (PKU), a disease resulting in the disability to degrade phenylalanine (Phe) is an inborn error with a 1 in 10,000 morbidity rate on average around the world which leads to neurotoxicity. As an potential alternative to a protein-restricted diet, oral intake of engineered probiotics degrading Phe inside the body is a promising treatment, currently at clinical stage II (Isabella, et al., 2018). However, limited transmembrane transport of Phe is a bottleneck to further improvement of the probiotic's activity. Here, we achieved simultaneous degradation of Phe both intracellularly and extracellularly by expressing genes encoding the Phe-metabolizing enzyme phenylalanine ammonia lyase (PAL) as an intracellularly free and a cell surface-immobilized enzyme in Escherichia coli Nissle 1917 (EcN) which overcomes the transportation problem. The metabolic engineering strategy was also combined with strengthening of Phe transportation, transportation of PAL-catalyzed trans-cinnamic acid and fixation of released ammonia. Administration of our final synthetic strain TYS8500 with PAL both displayed on the cell surface and expressed inside the cell to the PahF263S PKU mouse model reduced blood Phe concentration by 44.4% compared to the control EcN, independent of dietary protein intake. TYS8500 shows great potential in future applications for PKU therapy.
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Samuel L, Fera J, Basch CH. Lost in print: difficulty in reading online information pertaining to phenylketonuria. J Community Genet 2022; 14:185-188. [PMID: 36502490 PMCID: PMC10104971 DOI: 10.1007/s12687-022-00626-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 12/04/2022] [Indexed: 12/14/2022] Open
Abstract
Phenylketonuria (PKU) is the most prevalent inborn error of amino acid metabolism, necessitating patients to strictly restrict dietary phenylalanine. As this can be a confusing and concerning diagnosis, patients and loved ones will likely be drawn to learn more. A critical factor for citizens to harness the health-related digital information is to ensure that it is easy to read. This study assessed the readability of 100 digital articles related to PKU and explored the effect of the source of online information on the readability of these articles. For each article, 5 readability tests were conducted using on-line readability software. From the 100 assessed websites, 34% were commercially sourced. Of the remaining 66 sites, 40% had.org and 17% had.gov extensions. All 5 tests confirm that a large majority of the sample was written at an unacceptable reading level. In fact, over two-thirds of the sample received a readability score within the difficult range for three of the tests, while the remaining two deemed 49% and 45% of the sample as difficult to read, respectively. Commercially sourced websites were deemed to be more difficult to read than the other sites with respect to the two of the five measures. Despite the large amount of PKU information online, most of it may be incomprehensible to the average person and thus miss the mark in helping patients and caregivers manage their condition. Opportunities exist for authors of digital health promotional information to effectively achieve their goal by using comprehensible, easy-to-read language.
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Affiliation(s)
- Lalitha Samuel
- Department of Health Promotion and Nutrition Sciences, Lehman College, The City University of New York, Bronx, NY, 10468, USA.
| | - Joseph Fera
- Department of Mathematics, Lehman College, The City University of New York, Bronx, NY, 10468, USA
| | - Corey H Basch
- Department of Public Health, William Paterson University, Wayne, NJ, 07470, USA
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Liemburg GB, Huijbregts SCJ, Rutsch F, Feldmann R, Jahja R, Weglage J, Och U, Burgerhof JGM, van Spronsen FJ. Metabolic control during the neonatal period in phenylketonuria: associations with childhood IQ. Pediatr Res 2022; 91:874-878. [PMID: 34497359 DOI: 10.1038/s41390-021-01728-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 06/13/2021] [Accepted: 07/09/2021] [Indexed: 01/26/2023]
Abstract
BACKGROUND In phenylketonuria, treatment and subsequent lowering of phenylalanine levels usually occur within the first month of life. This study investigated whether different indicators of metabolic control during the neonatal period were associated with IQ during late childhood/early adolescence. METHODS Overall phenylalanine concentration during the first month of life (total "area under the curve"), proportion of phenylalanine concentrations above upper target level (360 μmol/L) and proportion below lower target level (120 μmol/L) during this period, diagnostic phenylalanine levels, number of days until phenylalanine levels were <360 μmol/L, and lifetime and concurrent phenylalanine levels were correlated with IQ scores of 64 PKU patients (mean age 10.8 years, SD 2.9). RESULTS Overall phenylalanine concentration and proportion of phenylalanine concentrations >360 μmol/L during the first month of life negatively correlated with IQ in late childhood/early adolescence. Separately, phenylalanine concentrations during different periods within the first month of life (0-10 days, 11-20 days, 21-30 days) were negatively correlated with later IQ as well, but correlation strengths did not differ significantly. No further significant associations were found. CONCLUSIONS In phenylketonuria, achievement of target-range phenylalanine levels during the neonatal period is important for cognition later in life, also when compared to other indicators of metabolic control. IMPACT In phenylketonuria, it remains unclear during which age periods or developmental stages metabolic control is most important for later cognitive outcomes. Phenylalanine levels during the neonatal period were clearly and negatively related to later IQ, whereas no significant associations were observed for other indices of metabolic control. This emphasizes the relative importance of this period for cognitive development in phenylketonuria. No further distinctions were observed in strength of associations with later IQ between different indicators of metabolic control during the neonatal period. Thus, achievement of good metabolic control within 1 month after birth appears "safe" with respect to later cognitive outcomes.
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Affiliation(s)
- Geertje B Liemburg
- Division of Metabolic Diseases, Beatrix Children's Hospital, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Stephan C J Huijbregts
- Department of Clinical Child and Adolescent Studies/Leiden Institute for Brain and Cognition, Leiden University, Leiden, The Netherlands.
| | - Frank Rutsch
- Department of Pediatrics, Münster University, University Children's Hospital, Münster, Germany
| | - Reinhold Feldmann
- Department of Pediatrics, Münster University, University Children's Hospital, Münster, Germany
| | - Rianne Jahja
- Division of Metabolic Diseases, Beatrix Children's Hospital, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Josef Weglage
- Department of Pediatrics, Münster University, University Children's Hospital, Münster, Germany
| | - Ulrike Och
- Department of Pediatrics, Münster University, University Children's Hospital, Münster, Germany
| | - Johannes G M Burgerhof
- Department of Epidemiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Francjan J van Spronsen
- Division of Metabolic Diseases, Beatrix Children's Hospital, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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Teruya KI, Remor E, Schwartz IVD. Factors that increase risk for poor adherence to phenylketonuria treatment in Brazilian patients. Am J Med Genet A 2021; 185:1991-2002. [PMID: 33765361 DOI: 10.1002/ajmg.a.62195] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 03/06/2021] [Accepted: 03/12/2021] [Indexed: 11/09/2022]
Abstract
Neurotoxic effects caused by high phenylalanine (Phe) in patients with phenylketonuria (PKU) can be avoided through dietary treatment. However, achieving the recommended Phe levels has been a challenge. This study aimed to investigate factors associated with adherence to PKU treatment among patients followed at a medical genetics public service in southern Brazil. Twenty-nine patients (early diagnosed, n = 20; late-diagnosed, n = 9) with classical (n = 16) or mild PKU (n = 13) aged 6-34 years (16.4 ± 7.5) and 16 caregivers were included. Blood Phe levels were recorded, and assessment tools measuring barriers to treatment, IQ, knowledge about disease, treatment, and perceived adherence were collected. Classical PKU patients showed higher current blood Phe levels than mild PKU patients (U = 37.000, p = 0.003). Lifetime and childhood Phe levels were associated with recent metabolic control (τ = 0.76, p = 0.000; τ = 0.70, p = 0.000, respectively). The perception of barriers to treatment was associated with a higher blood Phe level (τ = 0.39, p = 0.003). Tolerance to Phe, metabolic control throughout childhood, and perceived difficulty in living with demands of treatment are important factors of greater vulnerability to poor adherence in PKU patients.
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Affiliation(s)
- Katia Irie Teruya
- Institute of Psychology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Eduardo Remor
- Institute of Psychology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Ida Vanessa Doederlein Schwartz
- Department of Genetics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Medical Genetics Service, Hospital de Clinicas de Porto Alegre, Porto Alegre, Brazil
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Phenylketonuria Diagnosis by Massive Parallel Sequencing and Genotype-Phenotype Association in Brazilian Patients. Genes (Basel) 2020; 12:genes12010020. [PMID: 33375644 PMCID: PMC7824641 DOI: 10.3390/genes12010020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 12/04/2022] Open
Abstract
Phenylketonuria (PKU) is a common inborn error of amino acid metabolism in which the enzyme phenylalanine hydroxylase, which converts phenylalanine to tyrosine, is functionally impaired due to pathogenic variants in the PAH gene. Thirty-four Brazilian patients with a biochemical diagnosis of PKU, from 33 unrelated families, were analyzed through next-generation sequencing in the Ion Torrent PGM™ platform. Phenotype–genotype correlations were made based on the BioPKU database. Three patients required additional Sanger sequencing analyses. Twenty-six different pathogenic variants were identified. The most frequent variants were c.1315+1G>A (n = 8/66), c.473G>A (n = 6/66), and c.1162G>A (n = 6/66). One novel variant, c.524C>G (p.Pro175Arg), was found in one allele and was predicted as likely pathogenic by the American College of Medical Genetics and Genomics (ACMG) criteria. The molecular modeling of p.Pro175Arg indicated that this substitution can affect monomers binding in the PAH tetramer, which could lead to a change in the stability and activity of this enzyme. Next-generation sequencing was a fast and effective method for diagnosing PKU and is useful for patient phenotype prediction and genetic counseling.
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Teruya KI, Remor E, Schwartz IVD. Development of an inventory to assess perceived barriers related to PKU treatment. J Patient Rep Outcomes 2020; 4:29. [PMID: 32358708 PMCID: PMC7195505 DOI: 10.1186/s41687-020-00194-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 04/02/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND According to studies of phenylketonuria (PKU), the Brazilian population's metabolic control shows unsatisfactory indexes from childhood. Research on patients' perceived difficulties or barriers to adherence to treatment can help us to comprehend how these outcomes are associated. The present study aimed to: (1) describe the development of an inventory for identifying the most frequent and relevant perceived barriers to PKU treatment from the perspective of patients, caregivers, and healthcare professionals; (2) evaluate certain psychometric characteristics of the new measure; and, (3) explore potential predictors (sociodemographic and medical characteristics) that may contribute to increasing the number of perceived barriers and examine whether the number of barriers is associated with the degree of adherence shown by the patient. RESULTS Participants in the study were 23 patients with PKU (M age = 18.0 years; SD = 7.3; range 6 to 34 years; 69% early-treated) in classical (n = 11) and mild (n = 12) form, and 11 caregivers. The inventory, developed to ascertain perceived barriers to treatment, was completed by patients (≥ 13 years) and caregivers of patients aged 6 to 17 years. Analyses were conducted to investigate whether barrier inventory scores were associated with adherence to treatment as measured by phenylalanine levels in patients' medical records. Scores on the inventory differed across the patient age groups: adolescents had lower scores (i.e. reported fewer barriers) compared with those of adults (U = 8.000, p = 0.008); patients with better recent metabolic control also reported fewer perceived barriers than did patients with poor adherence (U = 20.000, p = 0.009); and the number of perceived barriers was positively associated with recent blood phenylalanine concentration (Kendall's taub = 0.41; p = 0.001). CONCLUSIONS These results suggest that the inventory has merit in assessing perceived barriers and support the need for further research on barriers perceived by PKU patients.
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Affiliation(s)
- Katia Irie Teruya
- Institute of Psychology, Universidade Federal do Rio Grande do Sul. Rua Ramiro Barcelos, 2600 (sala 219), Porto Alegre, Rio Grande do Sul, 90035003, Brazil
| | - Eduardo Remor
- Institute of Psychology, Universidade Federal do Rio Grande do Sul. Rua Ramiro Barcelos, 2600 (sala 219), Porto Alegre, Rio Grande do Sul, 90035003, Brazil.
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11
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Clayton RW, Langan EA, Ansell DM, de Vos IJHM, Göbel K, Schneider MR, Picardo M, Lim X, van Steensel MAM, Paus R. Neuroendocrinology and neurobiology of sebaceous glands. Biol Rev Camb Philos Soc 2020; 95:592-624. [PMID: 31970855 DOI: 10.1111/brv.12579] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 12/17/2019] [Accepted: 12/19/2019] [Indexed: 12/11/2022]
Abstract
The nervous system communicates with peripheral tissues through nerve fibres and the systemic release of hypothalamic and pituitary neurohormones. Communication between the nervous system and the largest human organ, skin, has traditionally received little attention. In particular, the neuro-regulation of sebaceous glands (SGs), a major skin appendage, is rarely considered. Yet, it is clear that the SG is under stringent pituitary control, and forms a fascinating, clinically relevant peripheral target organ in which to study the neuroendocrine and neural regulation of epithelia. Sebum, the major secretory product of the SG, is composed of a complex mixture of lipids resulting from the holocrine secretion of specialised epithelial cells (sebocytes). It is indicative of a role of the neuroendocrine system in SG function that excess circulating levels of growth hormone, thyroxine or prolactin result in increased sebum production (seborrhoea). Conversely, growth hormone deficiency, hypothyroidism, and adrenal insufficiency result in reduced sebum production and dry skin. Furthermore, the androgen sensitivity of SGs appears to be under neuroendocrine control, as hypophysectomy (removal of the pituitary) renders SGs largely insensitive to stimulation by testosterone, which is crucial for maintaining SG homeostasis. However, several neurohormones, such as adrenocorticotropic hormone and α-melanocyte-stimulating hormone, can stimulate sebum production independently of either the testes or the adrenal glands, further underscoring the importance of neuroendocrine control in SG biology. Moreover, sebocytes synthesise several neurohormones and express their receptors, suggestive of the presence of neuro-autocrine mechanisms of sebocyte modulation. Aside from the neuroendocrine system, it is conceivable that secretion of neuropeptides and neurotransmitters from cutaneous nerve endings may also act on sebocytes or their progenitors, given that the skin is richly innervated. However, to date, the neural controls of SG development and function remain poorly investigated and incompletely understood. Botulinum toxin-mediated or facial paresis-associated reduction of human sebum secretion suggests that cutaneous nerve-derived substances modulate lipid and inflammatory cytokine synthesis by sebocytes, possibly implicating the nervous system in acne pathogenesis. Additionally, evidence suggests that cutaneous denervation in mice alters the expression of key regulators of SG homeostasis. In this review, we examine the current evidence regarding neuroendocrine and neurobiological regulation of human SG function in physiology and pathology. We further call attention to this line of research as an instructive model for probing and therapeutically manipulating the mechanistic links between the nervous system and mammalian skin.
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Affiliation(s)
- Richard W Clayton
- Centre for Dermatology, School of Biological Sciences, University of Manchester, and NIHR Manchester Biomedical Research Centre, Stopford Building, Oxford Road, Manchester, M13 9PT, U.K.,Skin Research Institute of Singapore, Agency for Science, Technology and Research, 11 Mandalay Road, #17-01 Clinical Sciences Building, 308232, Singapore
| | - Ewan A Langan
- Centre for Dermatology, School of Biological Sciences, University of Manchester, and NIHR Manchester Biomedical Research Centre, Stopford Building, Oxford Road, Manchester, M13 9PT, U.K.,Department of Dermatology, Allergology und Venereology, University of Lübeck, Ratzeburger Allee 160, Lübeck, 23538, Germany
| | - David M Ansell
- Centre for Dermatology, School of Biological Sciences, University of Manchester, and NIHR Manchester Biomedical Research Centre, Stopford Building, Oxford Road, Manchester, M13 9PT, U.K.,Division of Cell Matrix Biology and Regenerative Medicine, University of Manchester, Michael Smith Building, Oxford Road, Manchester, M13 9PT, U.K
| | - Ivo J H M de Vos
- Skin Research Institute of Singapore, Agency for Science, Technology and Research, 11 Mandalay Road, #17-01 Clinical Sciences Building, 308232, Singapore
| | - Klaus Göbel
- Skin Research Institute of Singapore, Agency for Science, Technology and Research, 11 Mandalay Road, #17-01 Clinical Sciences Building, 308232, Singapore.,Department of Dermatology, Cologne Excellence Cluster on Stress Responses in Aging Associated Diseases (CECAD), and Centre for Molecular Medicine Cologne, The University of Cologne, Joseph-Stelzmann-Straße 26, Cologne, 50931, Germany
| | - Marlon R Schneider
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Max-Dohrn-Straße 8-10, Berlin, 10589, Germany
| | - Mauro Picardo
- Cutaneous Physiopathology and Integrated Centre of Metabolomics Research, San Gallicano Dermatological Institute IRCCS, Via Elio Chianesi 53, Rome, 00144, Italy
| | - Xinhong Lim
- Lee Kong Chian School of Medicine, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
| | - Maurice A M van Steensel
- Skin Research Institute of Singapore, Agency for Science, Technology and Research, 11 Mandalay Road, #17-01 Clinical Sciences Building, 308232, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
| | - Ralf Paus
- Centre for Dermatology, School of Biological Sciences, University of Manchester, and NIHR Manchester Biomedical Research Centre, Stopford Building, Oxford Road, Manchester, M13 9PT, U.K.,Dr. Phllip Frost Department of Dermatology and Cutaneous Surgery, University of Miami Miller School of Medicine, 1600 NW 10th Avenue, RMSB 2023A, Miami, FL, 33136, U.S.A.,Monasterium Laboratory, Mendelstraße 17, Münster, 48149, Germany
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12
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Darbà J. Characteristics, comorbidities, and use of healthcare resources of patients with phenylketonuria: a population-based study. J Med Econ 2019; 22:1025-1029. [PMID: 31237171 DOI: 10.1080/13696998.2019.1636381] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Background: Phenylketonuria is a well-known disease, yet the characteristics of the affected population and their use of healthcare resources have not been comprehensively evaluated. Patient characteristics and use of resources are subjects of interest for most governments, especially for a disease included in newborn screening programs. Objective: The aim of this study was to determine characteristics and use of healthcare resources of patients with phenylketonuria in the region of Catalonia. Methods: Records of 289 patients admitted with phenylketonuria between 2007 and 2017 were extracted from the PADRIS database that includes admission data from primary care centers, hospitals (inpatient and outpatient care), extended care facilities, and mental health centers. Results: The patient population was composed of 140 male patients and 149 female patients, and 102 patients were registered via newborn screening during the study period. Patients were admitted on average 2.19 times per year, mostly into primary care centers which concentrated the largest portion of direct medical expenses. Similar percentages of urgent and scheduled admissions were registered both in primary care and hospitals. Annual direct medical cost of treating patients with phenylketonuria was €667 per patient. Finally, 66.80% of the patients suffered from chronic conditions affecting two or more systems, likely to correspond to a wide variety of conditions. Conclusions: Altogether, phenylketonuria patient demographics and direct medical costs in Catalonia have been revised. Patients diagnosed with phenylketonuria appeared 1.3-times more likely to suffer from chronic conditions in distinct organ systems, which is expected to have an effect on their use of healthcare resources. These results support the need to adapt and improve the healthcare system, taking multimorbidity into consideration in an effort to control the medical expenses derived.
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Affiliation(s)
- Josep Darbà
- Universitat de Barcelona , Barcelona , Spain
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13
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van Vliet D, van der Goot E, van Ginkel WG, van Faassen MHJR, de Blaauw P, Kema IP, Martinez A, Heiner-Fokkema MR, van der Zee EA, van Spronsen FJ. The Benefit of Large Neutral Amino Acid Supplementation to a Liberalized Phenylalanine-Restricted Diet in Adult Phenylketonuria Patients: Evidence from Adult Pah-Enu2 Mice. Nutrients 2019; 11:E2252. [PMID: 31546852 PMCID: PMC6770592 DOI: 10.3390/nu11092252] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 09/13/2019] [Accepted: 09/17/2019] [Indexed: 11/16/2022] Open
Abstract
Many phenylketonuria (PKU) patients cannot adhere to the severe dietary restrictions as advised by the European PKU guidelines, which can be accompanied by aggravated neuropsychological impairments that, at least in part, have been attributed to brain monoaminergic neurotransmitter deficiencies. Supplementation of large neutral amino acids (LNAA) to an unrestricted diet has previously been shown to effectively improve brain monoamines in PKU mice of various ages. To determine the additive value of LNAA supplementation to a liberalized phenylalanine-restricted diet, brain and plasma monoamine and amino acid concentrations in 10 to 16-month-old adult C57Bl/6 PKU mice on a less severe phenylalanine-restricted diet with LNAA supplementation were compared to those on a non-supplemented severe or less severe phenylalanine-restricted diet. LNAA supplementation to a less severe phenylalanine-restricted diet was found to improve both brain monoamine and phenylalanine concentrations. Compared to a severe phenylalanine-restricted diet, it was equally effective to restore brain norepinephrine and serotonin even though being less effective to reduce brain phenylalanine concentrations. These results in adult PKU mice support the idea that LNAA supplementation may enhance the effect of a less severe phenylalanine-restricted diet and suggest that cerebral outcome of PKU patients treated with a less severe phenylalanine-restricted diet may be helped by additional LNAA treatment.
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Affiliation(s)
- Danique van Vliet
- Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, 9700 RB Groningen, The Netherlands.
| | - Els van der Goot
- Department of Molecular Neurobiology, Groningen Institute for Evolutionary Life Sciences (GELIFES), University of Groningen, 9700 RB Groningen, The Netherlands.
| | - Wiggert G van Ginkel
- Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, 9700 RB Groningen, The Netherlands.
| | - Martijn H J R van Faassen
- Department of Laboratory Medicine, University Medical Center Groningen, University of Groningen, 9700 RB Groningen, The Netherlands.
| | - Pim de Blaauw
- Department of Laboratory Medicine, University Medical Center Groningen, University of Groningen, 9700 RB Groningen, The Netherlands.
| | - Ido P Kema
- Department of Laboratory Medicine, University Medical Center Groningen, University of Groningen, 9700 RB Groningen, The Netherlands.
| | - Aurora Martinez
- Department of Biomedicine and K.G. Jebsen Centre for Neuropsychiatric Disorders, University of Bergen, 5009 Bergen, Norway.
| | - M Rebecca Heiner-Fokkema
- Department of Laboratory Medicine, University Medical Center Groningen, University of Groningen, 9700 RB Groningen, The Netherlands.
| | - Eddy A van der Zee
- Department of Molecular Neurobiology, Groningen Institute for Evolutionary Life Sciences (GELIFES), University of Groningen, 9700 RB Groningen, The Netherlands.
| | - Francjan J van Spronsen
- Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, 9700 RB Groningen, The Netherlands.
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14
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Phipps WS, Jones PM, Patel K. Amino and organic acid analysis: Essential tools in the diagnosis of inborn errors of metabolism. Adv Clin Chem 2019; 92:59-103. [PMID: 31472756 DOI: 10.1016/bs.acc.2019.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Inborn errors of metabolism (IEMs) are a large class of genetic disorders that result from defects in enzymes involved in energy production and metabolism of nutrients. For every metabolic pathway, there are defects that can occur and potentially result in an IEM. While some defects can go undetected in one's lifetime, some have moderate to severe clinical consequences. In the latter case, the biochemical defect leads to accumulation of metabolites and byproducts that are toxic or interfere with normal biological function. Disorders of amino acid metabolism, organic acid metabolism and the urea cycle comprise a large portion of IEMs. Two essential tools required for the diagnosis of these categories of disorders are amino acid and organic acid profiling. Most all clinical laboratories offering metabolic testing perform amino acid analysis, while organic acid profiling is restricted to more specialized pediatric hospitals and reference laboratories. In this chapter, we will provide an overview of various methodologies employed for amino acid and organic acid profiling as well as specific examples to demonstrate how these techniques are applied in clinical laboratories for the diagnosis of IEMs.
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Affiliation(s)
- William S Phipps
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, United States
| | - Patti M Jones
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, United States
| | - Khushbu Patel
- Department of Pathology, UT Southwestern Medical Center, Dallas, TX, United States.
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15
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Hasan MS, Feugang JM, Liao SF. A Nutrigenomics Approach Using RNA Sequencing Technology to Study Nutrient-Gene Interactions in Agricultural Animals. Curr Dev Nutr 2019; 3:nzz082. [PMID: 31414073 PMCID: PMC6686084 DOI: 10.1093/cdn/nzz082] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 06/08/2019] [Accepted: 07/08/2019] [Indexed: 11/15/2022] Open
Abstract
Thorough understanding of animal gene expression driven by dietary nutrients can be regarded as a bottom line of advanced animal nutrition research. Nutrigenomics (including transcriptomics) studies the effects of dietary nutrients on cellular gene expression and, ultimately, phenotypic changes in living organisms. Transcriptomics can be applied to investigate animal tissue transcriptomes at a defined nutritional state, which can provide a holistic view of intracellular RNA expression. As a novel transcriptomics approach, RNA sequencing (RNA-Seq) technology can monitor all gene expressions simultaneously in response to dietary intervention. The principle and history of RNA-Seq are briefly reviewed, and its 3 principal steps are described in this article. Application of RNA-Seq in different areas of animal nutrition research is summarized. Lastly, the application of RNA-Seq in swine science and nutrition is also reviewed. In short, RNA-Seq holds significant potential to be employed for better understanding the nutrient-gene interactions in agricultural animals.
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Affiliation(s)
- M Shamimul Hasan
- Department of Animal and Dairy Sciences, Mississippi State University, Mississippi State, MS, USA
| | - Jean M Feugang
- Department of Animal and Dairy Sciences, Mississippi State University, Mississippi State, MS, USA
| | - Shengfa F Liao
- Department of Animal and Dairy Sciences, Mississippi State University, Mississippi State, MS, USA
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16
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Buxbaum JN. Treatment of hereditary and acquired forms of transthyretin amyloidosis in the era of personalized medicine: the role of randomized controlled trials. Amyloid 2019; 26:55-65. [PMID: 30907141 DOI: 10.1080/13506129.2019.1575201] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
There have now been randomized controlled trials of four different therapeutics for hereditary amyloid polyneuropathy related to transthyretin (TTR) deposition and one for amyloidotic cardiomyopathy of both genetic and sporadic origin. It is likely that in the next few months those not already approved by either the US Food and Drug Administration (FDA) and/or the European Medicines Authority (EMA) will receive similar approvals for treatment for all or particular groups of patients. This is a far cry from circumstances less than 10 years ago when the only available therapy was gene replacement by liver transplant. The randomized controlled trials have shown that all the treatments (tafamidis, diflunisal, patisiran, and inotersen) are effective in the context of a clinical trial. However, we have very little idea of whether individual patients will respond in an equally positive way to all the drugs or whether there will be some who respond better to one or another or not respond at all, nor do we know whether combinations will be additive or synergistic. We lack validated markers of clinical response. While the small molecule TTR stabilizers increase serum TTR levels, the RNA-based drugs lower serum TTR. In the latter case, it is not clear that the reduction in serum TTR is related to the clinical response in a 1:1 fashion. Pharmaceutical companies have made substantial investments in the development of these agents and will clearly attempt to recoup those investments quickly. It is incumbent upon those of us who care for these patients to develop ways to assess the effects of therapy in the shortest possible time at the lowest possible cost. The better we are able to accomplish this the more likely it is that we will be able to treat the most patients in the most clinically efficient fashion regardless of their economic status. We now have the drugs we just have to figure out who should get them and when.
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Affiliation(s)
- Joel N Buxbaum
- a The Scripps Research Institute , San Diego , CA , USA.,b The Scintillon Institute , San Diego , CA , USA.,c Protego Biopharma , San Diego , CA , USA
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17
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Sikanyika NL, Parkington HC, Smith AI, Kuruppu S. Powering Amyloid Beta Degrading Enzymes: A Possible Therapy for Alzheimer's Disease. Neurochem Res 2019; 44:1289-1296. [PMID: 30806879 DOI: 10.1007/s11064-019-02756-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 02/15/2019] [Accepted: 02/17/2019] [Indexed: 12/23/2022]
Abstract
The accumulation of amyloid beta (Aβ) in the brain is believed to play a central role in the development and progression of Alzheimer's disease. Revisions to the amyloid cascade hypothesis now acknowledge the dynamic equilibrium in which Aβ exists and the importance of enzymes involved in the production and breakdown of Aβ in maintaining healthy Aβ levels. However, while a wealth of pharmacological and immunological therapies are being generated to inhibit the Aβ-producing enzymes, β-site APP cleavage enzyme 1 and γ-secretase, the therapeutic potential of stimulating Aβ-degrading enzymes such as neprilysin, endothelin-converting enzyme-1 and insulin-degrading enzyme remains relatively unexplored. Recent evidence indicates that increasing Aβ degradation as opposed to inhibiting synthesis is a more effective strategy to prevent Aβ build-up. Therefore Aβ degrading enzymes have become valuable targets of therapy. In this review, we discuss the pathway of Aβ synthesis and clearance along with the opportunities they present for therapeutic intervention, the benefits of increasing the expression/activity of Aβ-degrading enzymes, and the untapped therapeutic potential of enzyme activation.
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Affiliation(s)
- Nkumbu L Sikanyika
- Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Helena C Parkington
- Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
| | - A Ian Smith
- Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Sanjaya Kuruppu
- Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia.
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18
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Wang K, Shen M, Li H, Li X, He C. Reduced bone mineral density in Chinese children with phenylketonuria. J Pediatr Endocrinol Metab 2017; 30:651-656. [PMID: 28489557 DOI: 10.1515/jpem-2016-0308] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 04/03/2017] [Indexed: 12/27/2022]
Abstract
BACKGROUND Phenylketonuria (PKU) is an autosomal recessive metabolic disorder. Dietary control of classic PKU needs restriction of natural proteins. The diet results in unbalanced nutrition, which might affect the physical development of the patients. Our aim was to evaluate bone mineral density (BMD) in children with PKU. METHODS To investigate the BMD of children with PKU, 41 children with PKU and 64 healthy controls were recruited (all 3-4 years of age). Body weight and height, BMD, Phe blood levels, thyroid function, calcium, phosphorus, iron metabolism markers, and vitamin D3 were measured. RESULTS Body height and BMD of patients were lower than in controls. The BMD of controls was positively associated with age, body weight and height. In patients, BMD was positively associated with body weight. There was no correlation between Phe blood levels and BMD in patients. Blood levels of alkaline phosphatase were higher in patients compared to controls. Blood calcium levels were higher in 4-year-old patients, while the body weight was lower compared to controls. Thyroid function, iron metabolism markers, vitamin D3 levels and IGF-1 levels were normal. CONCLUSIONS Reduced BMD was observed in children with phenylketonuria, but the exact reasons for this remain to be elucidated.
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19
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Şirin S, Aydaş SB, Aslım B. Biochemical Evaluation of Phenylalanine Ammonia Lyase from Endemic Plant Cyathobasis fruticulosa (Bunge) Aellen. for the Dietary Treatment of Phenylketonuria. Food Technol Biotechnol 2016; 54:296-303. [PMID: 27956861 DOI: 10.17113/ftb.54.03.16.4519] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Enzyme substitution therapy with the phenylalanine ammonia lyase (PAL) is a new approach to the treatment of patients with phenylketonuria (PKU). This enzyme is responsible for the conversion of phenylalanine to trans-cinnamic acid. We assessed the PAL enzyme of the endemic plant Cyathobasis fruticulosa (Bunge) Aellen. for its possible role in the dietary treatment of PKU. The enzyme was found to have a high activity of (64.9±0.1) U/mg, with the optimum pH, temperature and buffer (Tris-HCl and l-phenylalanine) concentration levels of pH=8.8, 37 °C and 100 mM, respectively. Optimum enzyme activity was achieved at pH=4.0 and 7.5, corresponding to pH levels of gastric and intestinal juice, and NaCl concentration of 200 mM. The purification of the enzyme by 1.87-fold yielded an activity of 98.6 U/mg. PAL activities determined by HPLC analyses before and after purification were similar. Two protein bands, one at 70 and the other at 23 kDa, were determined by Western blot analysis of the enzyme. This enzyme is a potential candidate for serial production of dietary food and biotechnological products.
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Affiliation(s)
- Seda Şirin
- Gazi University, Faculty of Science, Department of Biology, TR-06500 Teknikokullar, Ankara, Turkey
| | - Selcen Babaoğlu Aydaş
- Gazi University, Vocational High School of Health Services, TR-06830 Gölbaşı, Ankara, Turkey
| | - Belma Aslım
- Gazi University, Faculty of Science, Department of Biology, TR-06500 Teknikokullar, Ankara, Turkey
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20
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Puzzling role of genetic risk factors in human longevity: "risk alleles" as pro-longevity variants. Biogerontology 2015; 17:109-27. [PMID: 26306600 PMCID: PMC4724477 DOI: 10.1007/s10522-015-9600-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 08/19/2015] [Indexed: 02/07/2023]
Abstract
Complex diseases are major contributors to human mortality in old age. Paradoxically, many genetic variants that have been associated with increased risks of such diseases are found in genomes of long-lived people, and do not seem to compromise longevity. Here we argue that trade-off-like and conditional effects of genes can play central role in this phenomenon and in determining longevity. Such effects may occur as result of: (i) antagonistic influence of gene on the development of different health disorders; (ii) change in the effect of gene on vulnerability to death with age (especially, from “bad” to “good”); (iii) gene–gene interaction; and (iv) gene–environment interaction, among other factors. A review of current knowledge provides many examples of genetic factors that may increase the risk of one disease but reduce chances of developing another serious health condition, or improve survival from it. Factors that may increase risk of a major disease but attenuate manifestation of physical senescence are also discussed. Overall, available evidence suggests that the influence of a genetic variant on longevity may be negative, neutral or positive, depending on a delicate balance of the detrimental and beneficial effects of such variant on multiple health and aging related traits. This balance may change with age, internal and external environments, and depend on genetic surrounding. We conclude that trade-off-like and conditional genetic effects are very common and may result in situations when a disease “risk allele” can also be a pro-longevity variant, depending on context. We emphasize importance of considering such effects in both aging research and disease prevention.
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21
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Vandenbossche E, Lucas C, Mistry L, Garfield E, Mitchell SC, Steventon GB. Phenylalanine monooxygenase and the sulfur oxygenation of S-carboxymethyl-l-cysteine in mice. Xenobiotica 2015; 46:379-84. [DOI: 10.3109/00498254.2015.1075259] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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22
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Pimentel FB, Alves RC, Oliva-Teles MT, Costa ASG, Fernandes TJR, Almeida MF, Torres D, Delerue-Matos C, Oliveira MBPP. Targeting specific nutrient deficiencies in protein-restricted diets: some practical facts in PKU dietary management. Food Funct 2015; 5:3151-9. [PMID: 25277724 DOI: 10.1039/c4fo00555d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Among aminoacidopathies, phenylketonuria (PKU) is the most prevalent one. Early diagnosis in the neonatal period with a prompt nutritional therapy (low natural-protein and phenylalanine diet, supplemented with phenylalanine-free amino acid mixtures and special low-protein foods) remains the mainstay of the treatment. Data considering nutrient contents of cooked dishes is lacking. In this study, fourteen dishes specifically prepared for PKU individuals were analysed, regarding the lipid profile and iron and zinc contents. These dishes are poor sources of essential nutrients like Fe, Zn or n-3 fatty acids, reinforcing the need for adequate supplementation to cover individual patients' needs. This study can contribute to a more accurate adjustment of PKU diets and supplementation in order to prevent eventual nutritional deficiencies. This study contributes to a better understanding of nutrient intake from PKU patients' meals, showing the need for dietary supplementation.
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Affiliation(s)
- Filipa B Pimentel
- REQUIMTE/Departamento de Ciências Químicas, Faculdade de Farmácia da Universidade do Porto, Rua de Jorge Viterbo Ferreira no. 228, 4050-313 Porto, Portugal
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Kochhar JS, Chan SY, Ong PS, Kang L. Clinical therapeutics for phenylketonuria. Drug Deliv Transl Res 2015; 2:223-37. [PMID: 25787029 DOI: 10.1007/s13346-012-0067-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Phenylketonuria was amongst the first of the metabolic disorders to be characterised, exhibiting an inborn error in phenylalanine metabolism due to a functional deficit of the enzyme phenylalanine hydroxylase. It affects around 700,000 people around the globe. Mutations in the gene coding for hepatic phenylalanine hydroxylase cause this deficiency resulting in elevated plasma phenylalanine concentrations, leading to cognitive impairment, neuromotor disorders and related behavioural symptoms. Inception of low phenylalanine diet in the 1950s marked a revolution in the management of phenylketonuria and has since been a vital element of all therapeutic regimens. However, compliance to dietary therapy has been found difficult and newer supplement approaches are being examined. The current development of gene therapy and enzyme replacement therapeutics may offer promising alternatives for the management of phenylketonuria. This review outlines the pathological basis of phenylketonuria, various treatment regimes, their associated challenges and the future prospects of each approach. Briefly, novel drug delivery systems which can potentially deliver therapeutic strategies in phenylketonuria have been discussed.
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Affiliation(s)
- Jaspreet Singh Kochhar
- Department of Pharmacy, National University of Singapore, 18 Science Drive 4, Block S4 Level 2, Singapore, Singapore, 117543
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Liemburg GB, Jahja R, van Spronsen FJ, de Sonneville LMJ, van der Meere JJ, Bosch AM, Hollak CEM, Rubio-Gozalbo ME, Brouwers MCGJ, Hofstede FC, de Vries MC, Janssen MCH, van der Ploeg AT, Langendonk JG, Huijbregts SCJ. Is BRIEF a useful instrument in day to day care of patients with phenylketonuria? Mol Genet Metab 2015; 114:425-30. [PMID: 25541101 DOI: 10.1016/j.ymgme.2014.12.302] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 12/05/2014] [Accepted: 12/05/2014] [Indexed: 11/24/2022]
Abstract
OBJECTIVES Despite early and continuous treatment many patients with phenylketonuria (PKU) still experience neurocognitive problems. Most problems have been observed in the domain of executive functioning (EF). For regular monitoring of EF, the use of the Behavior Rating Inventory of Executive Function (BRIEF) has been proposed. The aim of this study was to investigate whether the BRIEF is indeed a useful screening instrument in monitoring of adults with PKU. STUDY DESIGN Adult PKU patients (n = 55; mean age 28.3 ± 6.2 years) filled out the BRIEF-A (higher scores=poorer EF) and performed computerized tasks measuring executive functions (inhibition, cognitive flexibility, and working memory). The outcome of the BRIEF-A questionnaire was compared with the neurocognitive outcome as measured by three tasks from the Amsterdam Neuropsychological Tasks (ANT). RESULTS Forty-two percent of the PKU patients scored in the borderline/clinical range of the BRIEF-A. Six of the 55 patients (11%) scored >1 SD above the normative mean, mostly on the Metacognition Index. With respect to ANT measurements, patients mainly showed deficits in inhibitory control (34-36%) and cognitive flexibility (31-40%) as compared to the general Dutch population. No significant correlations between the two methods were found, which was confirmed with the Bland-Altman approach where no agreement between the two methods was observed. Only with respect to inhibitory control, patients scored significantly worse on both BRIEF-A and ANT classifications. No other associations between classification according to the BRIEF-A and classifications according to the ANT tasks were found. CONCLUSIONS Patients reporting EF problems in daily life are not necessarily those that present with core EF deficits. The results of this study suggest that regular self-administration of the BRIEF-A is not a sufficient way to monitor EF in adult PKU patients.
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Affiliation(s)
- Geertje B Liemburg
- Division of Metabolic Diseases, Beatrix Children's Hospital, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Rianne Jahja
- Division of Metabolic Diseases, Beatrix Children's Hospital, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Francjan J van Spronsen
- Division of Metabolic Diseases, Beatrix Children's Hospital, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Leo M J de Sonneville
- Department of Clinical Child and Adolescents Studies, Leiden Institute for Brain and Cognition, Leiden University, Leiden, The Netherlands
| | - Jaap J van der Meere
- Department of Developmental and Clinical Neuropsychology, University of Groningen, Groningen, The Netherlands
| | - Annet M Bosch
- Department of Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Carla E M Hollak
- Department of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - M Estela Rubio-Gozalbo
- Department of Pediatrics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Martijn C G J Brouwers
- Department of Internal Medicine and Endocrinology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Floris C Hofstede
- Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Maaike C de Vries
- Department of Pediatrics, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Mirian C H Janssen
- Department of Internal Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Ans T van der Ploeg
- Department of Pediatrics, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Janneke G Langendonk
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Stephan C J Huijbregts
- Department of Clinical Child and Adolescents Studies, Leiden Institute for Brain and Cognition, Leiden University, Leiden, The Netherlands.
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Moghal A, Mohler K, Ibba M. Mistranslation of the genetic code. FEBS Lett 2014; 588:4305-10. [PMID: 25220850 DOI: 10.1016/j.febslet.2014.08.035] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 08/28/2014] [Accepted: 08/29/2014] [Indexed: 01/02/2023]
Abstract
During mRNA decoding at the ribosome, deviations from stringent codon identity, or "mistranslation," are generally deleterious and infrequent. Observations of organisms that decode some codons ambiguously, and the discovery of a compensatory increase in mistranslation frequency to combat environmental stress have changed the way we view "errors" in decoding. Modern tools for the study of the frequency and phenotypic effects of mistranslation can provide quantitative and sensitive measurements of decoding errors that were previously inaccessible. Mistranslation with non-protein amino acids, in particular, is an enticing prospect for new drug therapies and the study of molecular evolution.
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Affiliation(s)
- Adil Moghal
- Ohio State Biochemistry Program, The Ohio State University, Columbus, OH 43210-1292, USA; Department of Microbiology, The Ohio State University, Columbus, OH 43210-1292, USA
| | - Kyle Mohler
- Department of Microbiology, The Ohio State University, Columbus, OH 43210-1292, USA; Center for RNA Biology, The Ohio State University, Columbus, OH 43210-1292, USA
| | - Michael Ibba
- Ohio State Biochemistry Program, The Ohio State University, Columbus, OH 43210-1292, USA; Department of Microbiology, The Ohio State University, Columbus, OH 43210-1292, USA; Center for RNA Biology, The Ohio State University, Columbus, OH 43210-1292, USA.
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Baruteau J, Nyabi O, Najimi M, Fauvart M, Sokal E. Adult human liver mesenchymal progenitor cells express phenylalanine hydroxylase. J Pediatr Endocrinol Metab 2014; 27:863-8. [PMID: 24825084 DOI: 10.1515/jpem-2013-0425] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 04/07/2014] [Indexed: 11/15/2022]
Abstract
Phenylketonuria (PKU) is one of the most prevalent inherited metabolic diseases and is accountable for a severe encephalopathy by progressive intoxication of the brain by phenylalanine. This results from an ineffective L-phenylalanine hydroxylase enzyme (PAH) due to a mutated phenylalanine hydroxylase (PAH) gene. Neonatal screening programs allow an early dietetic treatment with restrictive phenylalanine intake. This diet prevents most of the neuropsychological disabilities but remains challenging for lifelong compliance. Adult-derived human liver progenitor cells (ADHLPC) are a pool of precursors that can differentiate into hepatocytes. We aim to study PAH expression and PAH activity in a differenciated ADHLPC. ADHLPC were isolated from human hepatocyte primary culture of two different donors and differenciated under specific culture conditions. We demonstrated the high expression of PAH and a large increase of PAH activity in differenciated LPC. The age of the donor, the cellular viability after liver digestion and cryopreservation affects PAH activity. ADHLPC might therefore be considered as a suitable source for cell therapy in PKU.
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Camp KM, Parisi MA, Acosta PB, Berry GT, Bilder DA, Blau N, Bodamer OA, Brosco JP, Brown CS, Burlina AB, Burton BK, Chang CS, Coates PM, Cunningham AC, Dobrowolski SF, Ferguson JH, Franklin TD, Frazier DM, Grange DK, Greene CL, Groft SC, Harding CO, Howell RR, Huntington KL, Hyatt-Knorr HD, Jevaji IP, Levy HL, Lichter-Konecki U, Lindegren ML, Lloyd-Puryear MA, Matalon K, MacDonald A, McPheeters ML, Mitchell JJ, Mofidi S, Moseley KD, Mueller CM, Mulberg AE, Nerurkar LS, Ogata BN, Pariser AR, Prasad S, Pridjian G, Rasmussen SA, Reddy UM, Rohr FJ, Singh RH, Sirrs SM, Stremer SE, Tagle DA, Thompson SM, Urv TK, Utz JR, van Spronsen F, Vockley J, Waisbren SE, Weglicki LS, White DA, Whitley CB, Wilfond BS, Yannicelli S, Young JM. Phenylketonuria Scientific Review Conference: state of the science and future research needs. Mol Genet Metab 2014; 112:87-122. [PMID: 24667081 DOI: 10.1016/j.ymgme.2014.02.013] [Citation(s) in RCA: 157] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 02/25/2014] [Accepted: 02/26/2014] [Indexed: 01/17/2023]
Abstract
New developments in the treatment and management of phenylketonuria (PKU) as well as advances in molecular testing have emerged since the National Institutes of Health 2000 PKU Consensus Statement was released. An NIH State-of-the-Science Conference was convened in 2012 to address new findings, particularly the use of the medication sapropterin to treat some individuals with PKU, and to develop a research agenda. Prior to the 2012 conference, five working groups of experts and public members met over a 1-year period. The working groups addressed the following: long-term outcomes and management across the lifespan; PKU and pregnancy; diet control and management; pharmacologic interventions; and molecular testing, new technologies, and epidemiologic considerations. In a parallel and independent activity, an Evidence-based Practice Center supported by the Agency for Healthcare Research and Quality conducted a systematic review of adjuvant treatments for PKU; its conclusions were presented at the conference. The conference included the findings of the working groups, panel discussions from industry and international perspectives, and presentations on topics such as emerging treatments for PKU, transitioning to adult care, and the U.S. Food and Drug Administration regulatory perspective. Over 85 experts participated in the conference through information gathering and/or as presenters during the conference, and they reached several important conclusions. The most serious neurological impairments in PKU are preventable with current dietary treatment approaches. However, a variety of more subtle physical, cognitive, and behavioral consequences of even well-controlled PKU are now recognized. The best outcomes in maternal PKU occur when blood phenylalanine (Phe) concentrations are maintained between 120 and 360 μmol/L before and during pregnancy. The dietary management treatment goal for individuals with PKU is a blood Phe concentration between 120 and 360 μmol/L. The use of genotype information in the newborn period may yield valuable insights about the severity of the condition for infants diagnosed before maximal Phe levels are achieved. While emerging and established genotype-phenotype correlations may transform our understanding of PKU, establishing correlations with intellectual outcomes is more challenging. Regarding the use of sapropterin in PKU, there are significant gaps in predicting response to treatment; at least half of those with PKU will have either minimal or no response. A coordinated approach to PKU treatment improves long-term outcomes for those with PKU and facilitates the conduct of research to improve diagnosis and treatment. New drugs that are safe, efficacious, and impact a larger proportion of individuals with PKU are needed. However, it is imperative that treatment guidelines and the decision processes for determining access to treatments be tied to a solid evidence base with rigorous standards for robust and consistent data collection. The process that preceded the PKU State-of-the-Science Conference, the conference itself, and the identification of a research agenda have facilitated the development of clinical practice guidelines by professional organizations and serve as a model for other inborn errors of metabolism.
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Affiliation(s)
- Kathryn M Camp
- Office of Dietary Supplements, National Institutes of Health, Bethesda, MD 20982, USA.
| | - Melissa A Parisi
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | | | - Gerard T Berry
- Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | - Deborah A Bilder
- Department of Psychiatry, University of Utah, Salt Lake City, UT 84108, USA.
| | - Nenad Blau
- University Children's Hospital, Heidelberg, Germany; University Children's Hospital, Zürich, Switzerland.
| | - Olaf A Bodamer
- University of Miami Miller School of Medicine, Miami, FL 33136, USA.
| | - Jeffrey P Brosco
- University of Miami Mailman Center for Child Development, Miami, FL 33101, USA.
| | | | | | - Barbara K Burton
- Ann and Robert H. Lurie Children's Hospital of Chicago, Chicago, IL 60611, USA.
| | - Christine S Chang
- Agency for Healthcare Research and Quality, Rockville, MD 20850, USA.
| | - Paul M Coates
- Office of Dietary Supplements, National Institutes of Health, Bethesda, MD 20982, USA.
| | - Amy C Cunningham
- Tulane University Medical School, Hayward Genetics Center, New Orleans, LA 70112, USA.
| | | | - John H Ferguson
- Office of Rare Diseases Research, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20982, USA.
| | | | | | - Dorothy K Grange
- Washington University School of Medicine, St. Louis Children's Hospital, St. Louis, MO 63110, USA.
| | - Carol L Greene
- University of Maryland School of Medicine, Baltimore, MD 21201, USA.
| | - Stephen C Groft
- Office of Rare Diseases Research, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20982, USA.
| | - Cary O Harding
- Oregon Health & Science University, Portland, OR 97239, USA.
| | - R Rodney Howell
- University of Miami Miller School of Medicine, Miami, FL 33136, USA.
| | | | - Henrietta D Hyatt-Knorr
- Office of Rare Diseases Research, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20982, USA.
| | - Indira P Jevaji
- Office of Research on Women's Health, National Institutes of Health, Bethesda, MD 20817, USA.
| | - Harvey L Levy
- Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | - Uta Lichter-Konecki
- George Washington University, Children's National Medical Center, Washington, DC 20010, USA.
| | | | | | | | | | - Melissa L McPheeters
- Vanderbilt Evidence-based Practice Center, Institute for Medicine and Public Health, Nashville, TN 37203, USA.
| | - John J Mitchell
- McGill University Health Center, Montreal, Quebec H3H 1P3, Canada.
| | - Shideh Mofidi
- Maria Fareri Children's Hospital of Westchester Medical Center, Valhalla, NY 10595, USA.
| | - Kathryn D Moseley
- University of Southern California Keck School of Medicine, Los Angeles, CA 90033, USA.
| | - Christine M Mueller
- Office of Orphan Products Development, U.S. Food and Drug Administration, Silver Spring, MD 20993, USA.
| | - Andrew E Mulberg
- Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD 20993, USA.
| | - Lata S Nerurkar
- Office of Rare Diseases Research, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20982, USA.
| | - Beth N Ogata
- University of Washington, Seattle, WA 98195, USA.
| | - Anne R Pariser
- Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD 20993, USA.
| | - Suyash Prasad
- BioMarin Pharmaceutical Inc., San Rafael, CA 94901, USA.
| | - Gabriella Pridjian
- Tulane University Medical School, Hayward Genetics Center, New Orleans, LA 70112, USA.
| | | | - Uma M Reddy
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | | | | | - Sandra M Sirrs
- Vancouver General Hospital, University of British Columbia, Vancouver V5Z 1M9, Canada.
| | | | - Danilo A Tagle
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Susan M Thompson
- The Children's Hospital at Westmead, Sydney, NSW 2145, Australia.
| | - Tiina K Urv
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Jeanine R Utz
- University of Minnesota, Minneapolis, MN 55455, USA.
| | - Francjan van Spronsen
- University of Groningen, University Medical Center of Groningen, Beatrix Children's Hospital, Netherlands.
| | - Jerry Vockley
- University of Pittsburgh, Pittsburgh, PA 15224, USA.
| | - Susan E Waisbren
- Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | - Linda S Weglicki
- National Institute of Nursing Research, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Desirée A White
- Department of Psychology, Washington University, St. Louis, MO 63130, USA.
| | | | - Benjamin S Wilfond
- Seattle Children's Research Institute, University of Washington School of Medicine, Seattle, WA 98101, USA.
| | | | - Justin M Young
- The Young Face, Facial Plastic and Reconstructive Surgery, Cumming, GA 30041, USA.
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Pimentel FB, Alves RC, Costa AS, Fernandes TJ, Torres D, Almeida MF, Oliveira MBP. Nutritional composition of low protein and phenylalanine-restricted dishes prepared for phenylketonuric patients. Lebensm Wiss Technol 2014. [DOI: 10.1016/j.lwt.2013.12.031] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Neurocognitive evidence for revision of treatment targets and guidelines for phenylketonuria. J Pediatr 2014; 164:895-899.e2. [PMID: 24485821 DOI: 10.1016/j.jpeds.2013.12.015] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 11/14/2013] [Accepted: 12/11/2013] [Indexed: 11/22/2022]
Abstract
OBJECTIVES To compare the neurocognitive outcomes of patients with phenylketonuria (PKU) to determine whether decreasing phenylalanine (Phe) levels to <240 is preferable to the use of 360 μmol/L as an upper-target Phe level. An additional aim was to establish the influence of biochemical indices other than Phe on neurocognitive outcomes. STUDY DESIGN Patients with PKU (n = 63; mean age 10.8 ± 2.3 years) and healthy controls (n = 73; mean age 10.9 ± 2.2 years) performed computerized tasks measuring neurocognitive functions (inhibitory control, cognitive flexibility, and motor control). Lifetime and concurrent blood Phe levels, Phe-to-tyrosine ratio (Phe:Tyr), and Phe variations were examined in relation to neurocognitive outcomes using nonparametric tests and regression analyses. RESULTS Patients with PKU with Phe levels ≤240 μmol/L and healthy controls performed equally well. Patients with Phe levels between 240 and 360 μmol/L and ≥360 μmol/L performed more poorly than did controls across tasks. Patients with Phe levels ≤240 μmol/L performed significantly better than patients with levels between 240 and 360 μmol/L on tasks measuring inhibitory control and cognitive flexibility. Absolute Phe levels and Phe variation were the best predictors of motor control, whereas Phe:Tyr were the best predictors of inhibitory control. CONCLUSIONS The results of this study suggest that upper Phe targets should be lowered to optimize neurocognitive outcomes. Moreover, Phe variation and Phe:Tyr appear to be of additional value in treatment monitoring.
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Mei L, Song P, Kokudo N, Xu L, Tang W. Current situation and prospects of newborn screening and treatment for Phenylketonuria in China - compared with the current situation in the United States, UK and Japan. Intractable Rare Dis Res 2013; 2:106-14. [PMID: 25343113 PMCID: PMC4204557 DOI: 10.5582/irdr.2013.v2.4.106] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 11/30/2013] [Indexed: 12/16/2022] Open
Abstract
Phenylketonuria (PKU) is a treat-able and prevent-able inborn error of metabolism which leads to severe mental retardation and neurobehavioral abnormalities. A screening program, especially for early detection, combined with a Phe-restricted therapeutic diet can help to control the process of PKU of most patients. The China government has put more emphasis on newborn screening and treatment against PKU, yet by comparing the situation of newborn screening and treatment against PKU in China and the relatively developed countries - United States, United Kingdom and Japan, the newborn screening and treatment against PKU in China is relatively weak and many deficiencies are found. More studies concerning multi-stage target blood Phe concentration criteria, a policy that requires newborn screening has to be taken, better financial support for newborn screening, publicity for newborn screening, and national guidelines for treatment of PKU may be prospects in China and may provide some support for better development of newborn screening and treatment against PKU in China.
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Affiliation(s)
- Lin Mei
- Department of Health Care Management and Maternal and Child Health, Shandong University, Ji'nan, Shandong, China
- Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Peipei Song
- Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Norihiro Kokudo
- Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Lingzhong Xu
- Department of Health Care Management and Maternal and Child Health, Shandong University, Ji'nan, Shandong, China
- Address correspondence to: Dr. Lingzhong Xu, Department of Health Care Management and Maternal and Child Health, NO.110 mailbox, Shandong University, 44 Wenhuaxi Road, Ji'nan 250012, China. E-mail:
| | - Wei Tang
- Department of Health Care Management and Maternal and Child Health, Shandong University, Ji'nan, Shandong, China
- Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
- Dr. Wei Tang, Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan. E-mail:
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Cooper DN, Krawczak M, Polychronakos C, Tyler-Smith C, Kehrer-Sawatzki H. Where genotype is not predictive of phenotype: towards an understanding of the molecular basis of reduced penetrance in human inherited disease. Hum Genet 2013; 132:1077-130. [PMID: 23820649 PMCID: PMC3778950 DOI: 10.1007/s00439-013-1331-2] [Citation(s) in RCA: 423] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 06/15/2013] [Indexed: 02/06/2023]
Abstract
Some individuals with a particular disease-causing mutation or genotype fail to express most if not all features of the disease in question, a phenomenon that is known as 'reduced (or incomplete) penetrance'. Reduced penetrance is not uncommon; indeed, there are many known examples of 'disease-causing mutations' that fail to cause disease in at least a proportion of the individuals who carry them. Reduced penetrance may therefore explain not only why genetic diseases are occasionally transmitted through unaffected parents, but also why healthy individuals can harbour quite large numbers of potentially disadvantageous variants in their genomes without suffering any obvious ill effects. Reduced penetrance can be a function of the specific mutation(s) involved or of allele dosage. It may also result from differential allelic expression, copy number variation or the modulating influence of additional genetic variants in cis or in trans. The penetrance of some pathogenic genotypes is known to be age- and/or sex-dependent. Variable penetrance may also reflect the action of unlinked modifier genes, epigenetic changes or environmental factors. At least in some cases, complete penetrance appears to require the presence of one or more genetic variants at other loci. In this review, we summarize the evidence for reduced penetrance being a widespread phenomenon in human genetics and explore some of the molecular mechanisms that may help to explain this enigmatic characteristic of human inherited disease.
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Affiliation(s)
- David N. Cooper
- Institute of Medical Genetics, School of Medicine, Cardiff University, Heath Park, Cardiff, CF14 4XN UK
| | - Michael Krawczak
- Institute of Medical Informatics and Statistics, Christian-Albrechts University, 24105 Kiel, Germany
| | | | - Chris Tyler-Smith
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA UK
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de Groot MJ, Hoeksma M, Reijngoud DJ, de Valk HW, Paans AMJ, Sauer PJJ, van Spronsen FJ. Phenylketonuria: reduced tyrosine brain influx relates to reduced cerebral protein synthesis. Orphanet J Rare Dis 2013; 8:133. [PMID: 24007597 PMCID: PMC3847152 DOI: 10.1186/1750-1172-8-133] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 08/21/2013] [Indexed: 11/25/2022] Open
Abstract
Background In phenylketonuria (PKU), elevated blood phenylalanine (Phe) concentrations are considered to impair transport of large neutral amino acids (LNAAs) from blood to brain. This impairment is believed to underlie cognitive deficits in PKU via different mechanisms, including reduced cerebral protein synthesis. In this study, we investigated the hypothesis that impaired LNAA influx relates to reduced cerebral protein synthesis. Methods Using positron emission tomography, L-[1-11C]-tyrosine (11C-Tyr) brain influx and incorporation into cerebral protein were studied in 16 PKU patients (median age 24, range 16 – 47 years), most of whom were early and continuously treated. Data were analyzed by regression analyses, using either 11C-Tyr brain influx or 11C-Tyr cerebral protein incorporation as outcome variable. Predictor variables were baseline plasma Phe concentration, Phe tolerance, age, and 11C-Tyr brain efflux. For the modelling of cerebral protein incorporation, 11C-Tyr brain influx was added as a predictor variable. Results 11C-Tyr brain influx was inversely associated with plasma Phe concentrations (median 512, range 233 – 1362 μmol/L; delta adjusted R2=0.571, p=0.013). In addition, 11C-Tyr brain influx was positively associated with 11C-Tyr brain efflux (delta adjusted R2=0.098, p=0.041). Cerebral protein incorporation was positively associated with 11C-Tyr brain influx (adjusted R2=0.567, p<0.001). All additional associations between predictor and outcome variables were statistically nonsignificant. Conclusions Our data favour the hypothesis that an elevated concentration of Phe in blood reduces cerebral protein synthesis by impairing LNAA transport from blood to brain. Considering the importance of cerebral protein synthesis for adequate brain development and functioning, our results support the notion that PKU treatment be continued in adulthood. Future studies investigating the effects of impaired LNAA transport on cerebral protein synthesis in more detail are indicated.
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Affiliation(s)
- Martijn J de Groot
- Department of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
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Yew NS, Dufour E, Przybylska M, Putelat J, Crawley C, Foster M, Gentry S, Reczek D, Kloss A, Meyzaud A, Horand F, Cheng SH, Godfrin Y. Erythrocytes encapsulated with phenylalanine hydroxylase exhibit improved pharmacokinetics and lowered plasma phenylalanine levels in normal mice. Mol Genet Metab 2013; 109:339-44. [PMID: 23867524 DOI: 10.1016/j.ymgme.2013.05.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 05/15/2013] [Accepted: 05/15/2013] [Indexed: 10/26/2022]
Abstract
Enzyme replacement therapy is often hampered by the rapid clearance and degradation of the administered enzyme, limiting its efficacy and requiring frequent dosing. Encapsulation of therapeutic molecules into red blood cells (RBCs) is a clinically proven approach to improve the pharmacokinetics and efficacy of biologics and small molecule drugs. Here we evaluated the ability of RBCs encapsulated with phenylalanine hydroxylase (PAH) to metabolize phenylalanine (Phe) from the blood and confer sustained enzymatic activity in the circulation. Significant quantities of PAH were successfully encapsulated within murine RBCs (PAH-RBCs) with minimal loss of endogenous hemoglobin. While intravenously administered free PAH enzyme was rapidly eliminated from the blood within a few hours, PAH-RBCs persisted in the circulation for at least 10days. A single injection of PAH-RBCs was able to decrease Phe levels by nearly 80% in normal mice. These results demonstrate the ability of enzyme-loaded RBCs to metabolize circulating amino acids and highlight the potential to treat disorders of amino acid metabolism.
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Affiliation(s)
- Nelson S Yew
- Genzyme, a Sanofi Company, 49 New York Avenue, Framingham, MA 01701-9322, USA.
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Anjema K, van Rijn M, Hofstede FC, Bosch AM, Hollak CEM, Rubio-Gozalbo E, de Vries MC, Janssen MCH, Boelen CCA, Burgerhof JGM, Blau N, Heiner-Fokkema MR, van Spronsen FJ. Tetrahydrobiopterin responsiveness in phenylketonuria: prediction with the 48-hour loading test and genotype. Orphanet J Rare Dis 2013; 8:103. [PMID: 23842451 PMCID: PMC3711849 DOI: 10.1186/1750-1172-8-103] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 07/01/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND How to efficiently diagnose tetrahydrobiopterin (BH4) responsiveness in patients with phenylketonuria remains unclear. This study investigated the positive predictive value (PPV) of the 48-hour BH4 loading test and the additional value of genotype. METHODS Data of the 48-hour BH4 loading test (20 mg BH4/kg/day) were collected at six Dutch university hospitals. Patients with ≥30% phenylalanine reduction at ≥1 time points during the 48 hours (potential responders) were invited for the BH4 extension phase, designed to establish true-positive BH4 responsiveness. This is defined as long-term ≥30% reduction in mean phenylalanine concentration and/or ≥4 g/day and/or ≥50% increase of natural protein intake. Genotype was collected if available. RESULTS 177/183 patients successfully completed the 48-hour BH4 loading test. 80/177 were potential responders and 67/80 completed the BH4 extension phase. In 58/67 true-positive BH4 responsiveness was confirmed (PPV 87%). The genotype was available for 120/177 patients. 41/44 patients with ≥1 mutation associated with long-term BH4 responsiveness showed potential BH4 responsiveness in the 48-hour test and 34/41 completed the BH4 extension phase. In 33/34 true-positive BH4 responsiveness was confirmed. 4/40 patients with two known putative null mutations were potential responders; 2/4 performed the BH4 extension phase but showed no true-positive BH4 responsiveness. CONCLUSIONS The 48-hour BH4 loading test in combination with a classified genotype is a good parameter in predicting true-positive BH4 responsiveness. We propose assessing genotype first, particularly in the neonatal period. Patients with two known putative null mutations can be excluded from BH4 testing.
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Affiliation(s)
- Karen Anjema
- Division of Metabolic Diseases, University Medical Center Groningen, Beatrix Children’s Hospital CA33, PO box 30.001, Groningen 9700 RB, The Netherlands
| | - Margreet van Rijn
- Division of Metabolic Diseases, University Medical Center Groningen, Beatrix Children’s Hospital CA33, PO box 30.001, Groningen 9700 RB, The Netherlands
| | - Floris C Hofstede
- University Medical Center Utrecht, Wilhelmina Children’s Hospital, Utrecht, The Netherlands
| | - Annet M Bosch
- Academic Medical Center, University Hospital of Amsterdam, Amsterdam, The Netherlands
| | - Carla EM Hollak
- Academic Medical Center, University Hospital of Amsterdam, Amsterdam, The Netherlands
| | | | - Maaike C de Vries
- Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - Mirian CH Janssen
- Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | | | - Johannes GM Burgerhof
- Division of Metabolic Diseases, University Medical Center Groningen, Beatrix Children’s Hospital CA33, PO box 30.001, Groningen 9700 RB, The Netherlands
| | - Nenad Blau
- University Children’s Hospital, Heidelberg, Germany
- University Children’s Hospital, Zürich, Switzerland
| | - M Rebecca Heiner-Fokkema
- Division of Metabolic Diseases, University Medical Center Groningen, Beatrix Children’s Hospital CA33, PO box 30.001, Groningen 9700 RB, The Netherlands
| | - Francjan J van Spronsen
- Division of Metabolic Diseases, University Medical Center Groningen, Beatrix Children’s Hospital CA33, PO box 30.001, Groningen 9700 RB, The Netherlands
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Douglas TD, Jinnah HA, Bernhard D, Singh RH. The effects of sapropterin on urinary monoamine metabolites in phenylketonuria. Mol Genet Metab 2013; 109:243-50. [PMID: 23712020 DOI: 10.1016/j.ymgme.2013.04.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 04/24/2013] [Accepted: 04/24/2013] [Indexed: 11/28/2022]
Abstract
BACKGROUND Sapropterin dihydrochloride (BH4, tetrahydrobiopterin) can lower plasma phenylalanine (Phe) concentrations for a subset of patients with phenylketonuria (PKU), an inborn error of metabolism. Studies suggest that monoamine neurotransmitter concentrations are low in PKU patients. Sapropterin functions as a cofactor for hydroxylases specific to Phe, tyrosine, and tryptophan metabolism, pathways essential for catecholamine and serotonin synthesis. OBJECTIVE The objective of this study is to determine the impact of sapropterin on monoamine neurotransmitter status in patients with PKU. DESIGN 58 PKU subjects were provided 20 mg/kg of sapropterin for 1 month. Those who responded with at least a 15% decrease in plasma Phe received sapropterin for 1 year, while Non-responders discontinued it. After an additional 3 months, Responders who demonstrated increased Phe tolerance and decreased medical food dependence were classified as Definitive, whereas Responders unable to liberalize their diet without compromising plasma Phe control were identified as Provisional. At study visits, patients provided blood for plasma amino acids, 3-day diet records, and 12-hour urine samples analyzed for epinephrine (E), dopamine (DA), dihydroxyphenylacetate (DOPAC), homovanillic acid (HVA), 3-methoxytyramine (3MT), serotonin (5HT), and 5-hydroxyindole acetic acid (5HIAA) using HPLC with electrochemical detection. RESULTS Compared with healthy non-PKU controls, subjects with PKU had significantly lower baseline concentrations of DA, HVA, 3MT, 5HT, and 5HIAA (p < 0.001 for all). Medical food protein intake had a direct association with DA, HVA, 5HT, and 5HIAA during the study (p < 0.05 for all), while plasma Phe had an inverse association with these markers (p < 0.01 for all). DOPAC was also associated with plasma Phe throughout the year (p = 0.035), although not at baseline. Patients with PKU had a significant increase in HVA (p = 0.015) after 1 month of sapropterin. When stratifying by Responder and Non-Responder status, significance of HVA increase in Non-responders (p = 0.041) was confirmed, but not in Responders (p = 0.081). A declining trend in urinary 5HIAA, significant only after controlling for plasma Phe (p = 0.019), occurred for Definitive Responders during the 1-year study. CONCLUSION Urinary monoamine concentrations are low in patients with PKU and are influenced by oral sapropterin and medical food intake, highlighting the importance of these therapies to neurotransmitter metabolism in phenylketonuria.
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Affiliation(s)
- Teresa D Douglas
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA.
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Flydal MI, Martinez A. Phenylalanine hydroxylase: function, structure, and regulation. IUBMB Life 2013; 65:341-9. [PMID: 23457044 DOI: 10.1002/iub.1150] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 01/09/2013] [Indexed: 11/08/2022]
Abstract
Mammalian phenylalanine hydroxylase (PAH) catalyzes the rate-limiting step in the phenylalanine catabolism, consuming about 75% of the phenylalanine input from the diet and protein catabolism under physiological conditions. In humans, mutations in the PAH gene lead to phenylketonuria (PKU), and most mutations are mainly associated with PAH misfolding and instability. The established treatment for PKU is a phenylalanine-restricted diet and, recently, supplementation with preparations of the natural tetrahydrobiopterin cofactor also shows effectiveness for some patients. Since 1997 there has been a significant increase in the understanding of the structure, catalytic mechanism, and regulation of PAH by its substrate and cofactor, in addition to improved correlations between genotype and phenotype in PKU. Importantly, there has also been an increased number of studies on the structure and function of PAH from bacteria and lower eukaryote organisms, revealing an additional anabolic role of the enzyme in the synthesis of melanin-like pigments. In this review, we discuss these recent studies, which contribute to define the evolutionary adaptation of the PAH structure and function leading to sophisticated regulation for effective catabolic processing of phenylalanine in mammalian organisms.
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Affiliation(s)
- Marte I Flydal
- Department of Biomedicine and K.G. Jebsen Centre for Research on Neuropsychiatric Disorders, University of Bergen, Jonas Lies vei 91, 5009-Bergen, Norway
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Rocha JC, van Spronsen FJ, Almeida MF, Soares G, Quelhas D, Ramos E, Guimarães JT, Borges N. Dietary treatment in phenylketonuria does not lead to increased risk of obesity or metabolic syndrome. Mol Genet Metab 2012; 107:659-63. [PMID: 23137570 DOI: 10.1016/j.ymgme.2012.10.006] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Accepted: 10/09/2012] [Indexed: 01/10/2023]
Abstract
BACKGROUND Little is known about the consequences of the special energy enriched diet used to treat patients with phenylketonuria (PKU) in terms of obesity and metabolic syndrome (MetSyn) development. OBJECTIVE To investigate the prevalence of overweight and obesity, and its consequences in terms of body composition and MetSyn in early treated patients with PKU compared to controls. DESIGN A sample of 89 patients with PKU (3-30 y; 14.4±6.6 y) and 79 controls (3-47 y; 16.3±7.9 y) were studied. In the fasted state, anthropometric, body composition, blood pressure and analytical parameters [amino acids, glucose, insulin, total and HDL-cholesterol (HDL-c), triglycerides (TG), high sensitivity c-reactive protein and uric acid] were performed. Data on dietary intake was collected. BMI was classified using WHO criteria, while the definition from International Diabetes Federation (IDF) was used for MetSyn. RESULTS Prevalence of overweight and obesity (32.6% vs. 24.1%; p=0.293), body fat percentage (22% vs. 23.1%, p=0.581) and central obesity (36.9% vs. 36.4%, p=0.999) were comparable to controls. Patients revealed a higher TG/HDL-c (p<0.001). The prevalence of MetSyn was 1.5% and 6.1% in patients and controls, respectively. Patients and not controls with central obesity revealed a further significant increase in TG/HDL-c compared with those without central obesity (p=0.023). CONCLUSION Patients and controls were similar in terms of overweight and obesity, body composition and MetSyn. However, the dyslipidemia in patients with PKU in relation to overweight and obesity may help us trying to understand the course and the etiology of MetSyn not only in PKU but also in the general population.
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Affiliation(s)
- Júlio C Rocha
- Center of Medical Genetics Jacinto de Magalhães-INSA, IP, Porto, Portugal.
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Sarkissian CN, Ying M, Scherer T, Thöny B, Martinez A. The mechanism of BH4 -responsive hyperphenylalaninemia--as it occurs in the ENU1/2 genetic mouse model. Hum Mutat 2012; 33:1464-73. [PMID: 22644647 DOI: 10.1002/humu.22128] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2011] [Accepted: 05/15/2012] [Indexed: 01/07/2023]
Abstract
The Pah(enu1/enu2) (ENU1/2) mouse is a heteroallelic orthologous model displaying blood phenylalanine (Phe) concentrations characteristic of mild hyperphenylalaninemia. ENU1/2 mice also have reduced liver phenylalanine hydroxylase (PAH) protein content (∼20% normal) and activity (∼2.5% normal). The mutant PAH protein is highly ubiquitinated, which is likely associated with its increased misfolding and instability. The administration of a single subcutaneous injection of l-Phe (1.1 mg l-Phe/g body weight) leads to an approximately twofold to threefold increase of blood Phe and phenylalanine/tyrosine (Phe/Tyr) ratio, and a 1.6-fold increase of both nonubiquitinated PAH protein content and PAH activity. It also results in elevated concentrations of liver 6R-l-erythro-5,6,7,8-tetrahydrobiopterin (BH(4)), potentially through the influence of Phe on GTP cyclohydrolase I and its feedback regulatory protein. The increased BH(4) content seems to stabilize PAH. Supplementing ENU1/2 mice with BH(4) (50 mg/kg/day for 10 days) reduces the blood Phe/Tyr ratio within the mild hyperphenylalaninemic range; however, PAH content and activity were not elevated. It therefore appears that BH(4) supplementation of ENU1/2 mice increases Phe hydroxylation levels through a kinetic rather than a chaperone stabilizing effect. By boosting blood Phe concentrations, and by BH(4) supplementation, we have revealed novel insights into the processing and regulation of the ENU1/2-mutant PAH.
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Affiliation(s)
- Christineh N Sarkissian
- Department of Human Genetics, McGill University-Montreal Children's Hospital Research Institute, Montreal, Quebec, Canada
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Successful Live Birth following Preimplantation Genetic Diagnosis for Phenylketonuria in Day 3 Embryos by Specific Mutation Analysis and Elective Single Embryo Transfer. JIMD Rep 2012; 7:49-54. [PMID: 23430494 DOI: 10.1007/8904_2012_140] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2011] [Revised: 02/15/2012] [Accepted: 03/05/2012] [Indexed: 05/13/2023] Open
Abstract
Phenylketonuria (PKU) is an autosomal recessive inherited metabolic disorder caused by a complete or near-complete deficiency of the liver enzyme phenylalanine hydroxylase (PAH), which converts the amino acid phenylalanine to tyrosine, leading to the increase of blood and tissue concentration of phenylalanine to toxic levels. PKU is not life threatening but is treated through lifelong dietary management. If untreated, it can lead to severe learning disability, brain function abnormalities, behavioural and neurological problems. The non-life threatening nature of PKU has until now caused some debate on whether to licence its detection by preimplantation genetic diagnosis (PGD). We report the first successful live birth in the UK following single cell embryo biopsy and PGD for the detection of two different mutations in the (PAH) gene. This case highlights both an important scientific development as well as the ethical challenge in offering couples who carry PKU this new reproductive option when starting their family.
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Diet and energy-sensing inputs affect TorC1-mediated axon misrouting but not TorC2-directed synapse growth in a Drosophila model of tuberous sclerosis. PLoS One 2012; 7:e30722. [PMID: 22319582 PMCID: PMC3272037 DOI: 10.1371/journal.pone.0030722] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Accepted: 12/21/2011] [Indexed: 11/19/2022] Open
Abstract
The Target of Rapamycin (TOR) growth regulatory system is influenced by a number of different inputs, including growth factor signaling, nutrient availability, and cellular energy levels. While the effects of TOR on cell and organismal growth have been well characterized, this pathway also has profound effects on neural development and behavior. Hyperactivation of the TOR pathway by mutations in the upstream TOR inhibitors TSC1 (tuberous sclerosis complex 1) or TSC2 promotes benign tumors and neurological and behavioral deficits, a syndrome known as tuberous sclerosis (TS). In Drosophila, neuron-specific overexpression of Rheb, the direct downstream target inhibited by Tsc1/Tsc2, produced significant synapse overgrowth, axon misrouting, and phototaxis deficits. To understand how misregulation of Tor signaling affects neural and behavioral development, we examined the influence of growth factor, nutrient, and energy sensing inputs on these neurodevelopmental phenotypes. Neural expression of Pi3K, a principal mediator of growth factor inputs to Tor, caused synapse overgrowth similar to Rheb, but did not disrupt axon guidance or phototaxis. Dietary restriction rescued Rheb-mediated behavioral and axon guidance deficits, as did overexpression of AMPK, a component of the cellular energy sensing pathway, but neither was able to rescue synapse overgrowth. While axon guidance and behavioral phenotypes were affected by altering the function of a Tor complex 1 (TorC1) component, Raptor, or a TORC1 downstream element (S6k), synapse overgrowth was only suppressed by reducing the function of Tor complex 2 (TorC2) components (Rictor, Sin1). These findings demonstrate that different inputs to Tor signaling have distinct activities in nervous system development, and that Tor provides an important connection between nutrient-energy sensing systems and patterning of the nervous system.
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Underhaug J, Aubi O, Martinez A. Phenylalanine hydroxylase misfolding and pharmacological chaperones. Curr Top Med Chem 2012; 12:2534-45. [PMID: 23339306 PMCID: PMC3664513 DOI: 10.2174/1568026611212220008] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Revised: 08/28/2012] [Accepted: 08/29/2012] [Indexed: 12/15/2022]
Abstract
Phenylketonuria (PKU) is a loss-of-function inborn error of metabolism. As many other inherited diseases the main pathologic mechanism in PKU is an enhanced tendency of the mutant phenylalanine hydroxylase (PAH) to misfold and undergo ubiquitin-dependent degradation. Recent alternative approaches with therapeutic potential for PKU aim at correcting the PAH misfolding, and in this respect pharmacological chaperones are the focus of increasing interest. These compounds, which often resemble the natural ligands and show mild competitive inhibition, can rescue the misfolded proteins by stimulating their renaturation in vivo. For PKU, a few studies have proven the stabilization of PKU-mutants in vitro, in cells, and in mice by pharmacological chaperones, which have been found either by using the tetrahydrobiopterin (BH(4)) cofactor as query structure for shape-focused virtual screening or by high-throughput screening of small compound libraries. Both approaches have revealed a number of compounds, most of which bind at the iron-binding site, competitively with respect to BH(4). Furthermore, PAH shares a number of ligands, such as BH(4), amino acid substrates and inhibitors, with the other aromatic amino acid hydroxylases: the neuronal/neuroendocrine enzymes tyrosine hydroxylase (TH) and the tryptophan hydroxylases (TPHs). Recent results indicate that the PAH-targeted pharmacological chaperones should also be tested on TH and the TPHs, and eventually be derivatized to avoid unwanted interactions with these other enzymes. After derivatization and validation in animal models, the PAH-chaperoning compounds represent novel possibilities in the treatment of PKU.
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Affiliation(s)
| | | | - Aurora Martinez
- Department of Biomedicine, and K.G. Jebsen Centre for Research on Neuropsychiatric Disorders, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway
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Abstract
Phenylketonuria is the most common, inherited aminoacidopathy associated with brain injury. To date, no study has focused on the neuropathology of the genetic mouse model of phenylketonuria, BTBR-Pah(enu2). We examined dendritic spines and synapses in the CA1 and prefrontal cortex among the wild-type, heterozygous, and BTBR-Pah(enu2) mice. A reduced density of dendritic spines, a shortened length of the presynaptic active zone, a widened synaptic cleft, and decreased thickness of postsynaptic density were revealed in BTBR-Pah(enu2) mice. Meanwhile, the phosphorylation at Thr286 of Ca(2+)/calmodulin-dependent protein kinase IIα was alerted in BTBR-Pah(enu2) mice. These findings revealed that phenylketonuria-related brain impairment is accompanied with abnormalities of dendritic spines and synapses. The dysfunction of Ca(2+)/calmodulin-dependent protein kinase IIα may result in an impaired synaptic function.
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Vela-Amieva M, Ibarra-González I, Fernández-Lainez C, Monroy-Santoyo S, Guillén-López S, Belmont-Martínez L, Hernández-Montiel A. Causes of delay in referral of patients with phenylketonuria to a specialized reference centre in Mexico. J Med Screen 2011; 18:115-20. [DOI: 10.1258/jms.2011.011028] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Objective To expose causes leading to the delayed arrival of phenylketonuria (PKU) patients at a governmental reference centre (RC), and to describe their clinical characteristics. Material and methods PKU files registered during the past 18 years at the National Institute of Pediatrics in Mexico City were evaluated. Patients were classified into two groups according to their age at arrival: Group I (early reference), patients arriving during the first month of life; and Group II (late reference), those who arrived after thirty days of age. Time and causes of delay were documented. Results Of 57 recorded files, 10 were classified in Group I and 47 in Group II. Causes leading to the late arrival of Group II patients were absence of routine newborn screening (NBS), PKU not included in the routine NBS, sampling after the recommended age, false negative result, results without interpretation and/or instructions to follow, delayed notification of results, poor medical criteria of attending physician, difficulties in obtaining confirmatory tests, and administrative failures. Conclusion The main cause of late referral of PKU patients was the absence of PKU testing. As a developing country, Mexico still faces challenges in the proper functioning and expansion of the NBS programme. Most PKU patients arrived at the RC late, presenting with varying degrees of the clinical spectrum. Incorporating PKU testing into the already established Mexican NBS system and adding quality indicators to guarantee proper operation in all NBS phases is necessary to achieve the goal of identifying, referring, diagnosing, and treating patients promptly.
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Affiliation(s)
- M Vela-Amieva
- Laboratorio de Errores Innatos del Metabolismo y Tamiz, Instituto Nacional de Pediatría, Secretaría de Salud, México
| | - I Ibarra-González
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México
| | - C Fernández-Lainez
- Laboratorio de Errores Innatos del Metabolismo y Tamiz, Instituto Nacional de Pediatría, Secretaríade Salud, México
| | - S Monroy-Santoyo
- Laboratorio de Errores Innatos del Metabolismo y Tamiz, Instituto Nacional de Pediatría, Secretaríade Salud, México
| | - S Guillén-López
- Laboratorio de Errores Innatos del Metabolismo y Tamiz, Instituto Nacional de Pediatría, Secretaría de Salud, México
| | - L Belmont-Martínez
- Laboratorio de Errores Innatos del Metabolismo y Tamiz, Instituto Nacional de Pediatría, Secretaríade Salud, México
| | - A Hernández-Montiel
- Laboratorio de Errores Innatos del Metabolismo y Tamiz, Instituto Nacional de Pediatría, Secretaríade Salud, México
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Vaidyanathan K, Narayanan MP, Vasudevan DM. Organic acidurias: an updated review. Indian J Clin Biochem 2011; 26:319-25. [PMID: 23024466 PMCID: PMC3210240 DOI: 10.1007/s12291-011-0134-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Accepted: 04/17/2011] [Indexed: 01/07/2023]
Abstract
Organic acidurias are an important class of inherited metabolic disorders arising due to defect in intermediary metabolic pathways of carbohydrate, amino acids and fatty acid oxidation. This review summarizes the current knowledge about the important organic acidurias in the Indian population. Specifically, diagnosis and principles of treatment of organic acidurias are covered. The salient features of common organic acidurias as well as their prevalence in various parts of the world are reviewed in some detail.
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Affiliation(s)
- Kannan Vaidyanathan
- Department of Biochemistry, Metabolic Disorders Division, Amrita Institute of Medical Science, AIMS Ponekkara PO, Kochi, Kerala 682 041 India
| | - M. P. Narayanan
- Department of Biochemistry, Metabolic Disorders Division, Amrita Institute of Medical Science, AIMS Ponekkara PO, Kochi, Kerala 682 041 India
| | - D. M. Vasudevan
- Department of Biochemistry, Metabolic Disorders Division, Amrita Institute of Medical Science, AIMS Ponekkara PO, Kochi, Kerala 682 041 India
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Crews D, Gore AC. Life imprints: living in a contaminated world. ENVIRONMENTAL HEALTH PERSPECTIVES 2011; 119:1208-10. [PMID: 21571618 PMCID: PMC3230404 DOI: 10.1289/ehp.1103451] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Accepted: 05/13/2011] [Indexed: 05/07/2023]
Abstract
BACKGROUND The links between nature and nurture need to be redefined to accommodate anthropogenic chemical contamination. Although some local remediation of contamination has occurred, at the global level this is simply not possible. Contaminants are spread by population migration, by introduction via the food chain, and through air and water currents, even to regions that were never exposed directly to these environmental insults. In recognizing and accepting this worldwide change, we must move on and consider the types of adaptations that could occur as a consequence. OBJECTIVES We propose a paradigm shift in the field that integrates various disciplines involved in the study of environmental contamination to recognize that contamination is widespread and cannot be remedied at the global level. DISCUSSION Greater effort must be placed on integrative and interdisciplinary studies that explicitly illuminate how the causal mechanisms and functional outcomes of related processes operate at each level of biological organization while at the same time revealing the relations among the levels. CONCLUSIONS To anticipate and understand the future, we must devote more study to what is likely to happen and less to what has happened. Only then will we begin to understand how ancestral environmental exposures act at both the level of the individual and the level of their descendants to influence all aspects of life history.
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Liang L, Gu X, Li D, Lu L. The Expression and Phosphorylation of Acid Sensing Ion Channel 1a in the Brain of a Mouse Model of Phenylketonuria. Int J Neurosci 2011; 121:399-404. [DOI: 10.3109/00207454.2011.568655] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Abstract
Phenylketonuria (PKU) is an inherited disorder of amino acid metabolism caused by deficiency of the enzyme phenylalanine hydroxylase (PAH). Historically PKU was a common genetic cause of severe learning difficulties and developmental delay, but with the introduction of newborn screening and early dietary management, it has become a treatable disease and people born with PKU should now have IQs and achievements similar to their peers. Dietary treatment, however, involves lifestyle changes that pervade most aspects of daily life for an individual and their family. A simple pharmacological treatment for PKU would have a great appeal. Sapropterin hydrochloride is a synthetic form of tetrahydrobiopterin, the cofactor for PAH. A proportion of mutant PAH enzymes show enhanced activity in the presence of pharmacological doses of sapropterin and, for some patients with milder forms of PKU, sapropterin can effectively lower plasma phenylalanine levels. This article discusses the potential place for sapropterin in the management of PKU and how this expensive orphan drug is being integrated into patient care in different healthcare systems.
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Affiliation(s)
- Robin Lachmann
- Charles Dent Metabolic Unit, Box 92, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
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