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Ferreira F, Azevedo L, Neiva R, Sousa C, Fonseca H, Marcão A, Rocha H, Carmona C, Ramos S, Bandeira A, Martins E, Campos T, Rodrigues E, Garcia P, Diogo L, Ferreira AC, Sequeira S, Silva F, Rodrigues L, Gaspar A, Janeiro P, Amorim A, Vilarinho L. Phenylketonuria in Portugal: Genotype-phenotype correlations using molecular, biochemical, and haplotypic analyses. Mol Genet Genomic Med 2021; 9:e1559. [PMID: 33465300 PMCID: PMC8104178 DOI: 10.1002/mgg3.1559] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 10/29/2020] [Indexed: 11/12/2022] Open
Abstract
Background The impairment of the hepatic enzyme phenylalanine hydroxylase (PAH) causes elevation of phenylalanine levels in blood and other body fluids resulting in the most common inborn error of amino acid metabolism (phenylketonuria). Persistently high levels of phenylalanine lead to irreversible damage to the nervous system. Therefore, early diagnosis of the affected individuals is important, as it can prevent clinical manifestations of the disease. Methods In this report, the biochemical and genetic findings performed in 223 patients diagnosed through the Portuguese Neonatal Screening Program (PNSP) are presented. Results Overall, the results show that a high overlap exists between different types of variants and phenylalanine levels. Molecular analyses reveal a wide mutational spectrum in our population with a total of 56 previously reported variants, most of them found in compound heterozygosity (74% of the patients). Intragenic polymorphic markers were used to assess the haplotypic structure of mutated chromosomes for the most frequent variants found in homozygosity in our population (p.Ile65Thr, p.Arg158Gln, p.Leu249Phe, p.Arg261Gln, p.Val388Met, and c.1066‐11G>A). Conclusion Our data reveal high heterogeneity at the biochemical and molecular levels and are expected to provide a better understanding of the molecular basis of this disease and to provide clues to elucidate genotype–phenotype correlations.
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Affiliation(s)
- Filipa Ferreira
- Newborn Screening, Metabolic and Genetics Unit, Department of Human Genetics, National Institute of Health Dr Ricardo Jorge, Porto, Portugal
| | - Luísa Azevedo
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IPATIMUP - Instituto de Patologia e Imunologia Molecular da Universidade do Porto, Porto, Portugal.,FCUP - Faculty of Sciences, University of Porto, Porto, Portugal
| | - Raquel Neiva
- Newborn Screening, Metabolic and Genetics Unit, Department of Human Genetics, National Institute of Health Dr Ricardo Jorge, Porto, Portugal
| | - Carmen Sousa
- Newborn Screening, Metabolic and Genetics Unit, Department of Human Genetics, National Institute of Health Dr Ricardo Jorge, Porto, Portugal
| | - Helena Fonseca
- Newborn Screening, Metabolic and Genetics Unit, Department of Human Genetics, National Institute of Health Dr Ricardo Jorge, Porto, Portugal
| | - Ana Marcão
- Newborn Screening, Metabolic and Genetics Unit, Department of Human Genetics, National Institute of Health Dr Ricardo Jorge, Porto, Portugal
| | - Hugo Rocha
- Newborn Screening, Metabolic and Genetics Unit, Department of Human Genetics, National Institute of Health Dr Ricardo Jorge, Porto, Portugal
| | - Célia Carmona
- Newborn Screening, Metabolic and Genetics Unit, Department of Human Genetics, National Institute of Health Dr Ricardo Jorge, Porto, Portugal
| | - Sónia Ramos
- Newborn Screening, Metabolic and Genetics Unit, Department of Human Genetics, National Institute of Health Dr Ricardo Jorge, Porto, Portugal
| | - Anabela Bandeira
- Inherited Metabolic Disease Reference Center, Pediatric Department, Centro Hospitalar Universitário do Porto, Porto, Portugal
| | - Esmeralda Martins
- Inherited Metabolic Disease Reference Center, Pediatric Department, Centro Hospitalar Universitário do Porto, Porto, Portugal
| | - Teresa Campos
- Metabolic Diseases Unit, Pediatric Department, University Center São João Hospital - HSJ, Porto, Portugal
| | - Esmeralda Rodrigues
- Metabolic Diseases Unit, Pediatric Department, University Center São João Hospital - HSJ, Porto, Portugal
| | - Paula Garcia
- Inherited Metabolic Disease Reference Center, Pediatric Hospital, Hospital and University Center of Coimbra, Coimbra, Portugal
| | - Luísa Diogo
- Inherited Metabolic Disease Reference Center, Pediatric Hospital, Hospital and University Center of Coimbra, Coimbra, Portugal
| | - Ana Cristina Ferreira
- Metabolic Unit, Hospital Dona Estefânia, Centro Hospitalar Universitário Lisboa Central, Lisbon, Portugal
| | - Silvia Sequeira
- Metabolic Unit, Hospital Dona Estefânia, Centro Hospitalar Universitário Lisboa Central, Lisbon, Portugal
| | - Francisco Silva
- Pediatric Department, Hospital Central of Funchal, Funchal, Portugal
| | - Luísa Rodrigues
- Pediatrics Department, Hospital of Divino Espírito Santo of Ponta Delgada, EPE, Ponta Delgada, Azores, Portugal
| | - Ana Gaspar
- Inherited Metabolic Disease Reference Center, Lisbon North University Hospital Center (CHULN), EPE, Lisboa, Portugal
| | - Patrícia Janeiro
- Inherited Metabolic Disease Reference Center, Lisbon North University Hospital Center (CHULN), EPE, Lisboa, Portugal
| | - António Amorim
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IPATIMUP - Instituto de Patologia e Imunologia Molecular da Universidade do Porto, Porto, Portugal.,FCUP - Faculty of Sciences, University of Porto, Porto, Portugal
| | - Laura Vilarinho
- Newborn Screening, Metabolic and Genetics Unit, Department of Human Genetics, National Institute of Health Dr Ricardo Jorge, Porto, Portugal.,Research and Development Unit, Department of Human Genetics, National Institute of Health Dr Ricardo Jorge, Porto, Portugal
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Alibakhshi R, Moradi K, Ghadiri K. The status of PAH gene-VNTR alleles and mini-haplotypes associations with PAH gene mutations in Iranian Kurdish PKU patients. Med J Islam Repub Iran 2019; 33:88. [PMID: 31696082 PMCID: PMC6825400 DOI: 10.34171/mjiri.33.88] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Indexed: 11/17/2022] Open
Abstract
Background: The analysis of haplotypes/mini-haplotypes in the PAH gene has been used as an informative tool in several genetic anthropology studies. Considering the notion that Iranian population is one of the most heterogeneous i the world, this study was conducted to evaluate the association of VNTR-STR mini-haplotypes with the PAH gene mutations in PKU patients in Kermanshah province. Methods: A total of 24 unrelated Kurdish PKU patients with the known PAH gene causing mutations and 72 healthy controls were selected. The DNA fragments containing VNTR and STR systems were amplified by polymerase chain reaction (PCR). For VNTR system, PCR products were separated using electrophoresis on 2.5% agarose gel. For STR system, the samples were analyzed using DNA sequencing analysis version 5.2 software. Results: Overall, 5 PAH-VNTR-alleles, including VNTR3, 7, 8, 9, 12, and 3 PAH-STR-alleles, including STR238, 242, and 250, were detected in this study. VNTR3 and 8 alleles had the most frequency among healthy controls. Also, 6 different mini-haplotype alleles were found to be associated with PKU chromosomes. The 2 most prevalent mutations in Kermanshah province, IVS2+5G>C and IVS9+5G>A, were strongly linked to mini-haplotypes 9/242 and 8/238, respectively. Conclusion: The distributions and frequencies of VNTR alleles in Kurdish population have the most similarity to alleles previously described in European Caucasian families. Moreover, since the most common mutations in Kermanshah PKU chromosomes are rare and this was the first study on mini-haplotypes VNTR/STR among Iranian Kurdish PKU patients, given that this study was the first of its kind, it was not possible to compare its results with that of other studies on Iranian and non-Iranian populations.
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Affiliation(s)
- Reza Alibakhshi
- Department of Biochemistry, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Keivan Moradi
- Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Keyghobad Ghadiri
- Infectious Disease Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran
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Demirdas S, Coakley KE, Bisschop PH, Hollak CEM, Bosch AM, Singh RH. Bone health in phenylketonuria: a systematic review and meta-analysis. Orphanet J Rare Dis 2015; 10:17. [PMID: 25758373 PMCID: PMC4340652 DOI: 10.1186/s13023-015-0232-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Accepted: 01/25/2015] [Indexed: 01/09/2023] Open
Abstract
Patients with Phenylketonuria (PKU) reportedly have decreased bone mineral density (BMD). The primary aim of this study was to perform a systematic review and meta-analysis to determine the extent and significance of low BMD in early treated patients with PKU. Secondary aims were to assess other bone status indicators including bone turnover markers (BTM) and to define areas for future research. Two research teams (Amsterdam, Netherlands and Atlanta, USA) performed literature searches for articles reporting data on BMD, osteopenia and osteoporosis, BTM or other bone indicators in patients with PKU. Included articles were compared between research teams and assessed for quality and risk of bias. A total of 13 unique articles were included; 11/13 articles reported BMD including a total of 360 patients. Ten out of 11 articles found BMD was significantly lower in patients with PKU. Meta-analyses for total BMD (TBMD; 3 studies; n = 133), lumbar spine BMD (LBMD; 7 studies; n = 247), and femoral neck BMD (FBMD; 2 studies; n = 78) Z-scores were performed. Overall effect sizes were: TBMD -0.45 (95% CI -0.61, -0.28); LBMD -0.70 (95% CI -0.82, -0.57); FBMD -0.96 (95% CI -1.42, -0.49). Definitions of osteopenia and osteoporosis were highly heterogeneous between studies and did not align with World Health Organization standards and the International Society for Clinical Densitometry positions on BMD measurement. Despite individual study findings of low BMD indicating higher risk of osteoporosis, pooled available data suggest reduction in BMD is not clinically important when using standard definitions of low BMD. Results from studies evaluating BTM are inconclusive. Phenylalanine concentration, vitamin D, PTH, and nutrient intake do not correlate with BMD or BTM. We recommend forthcoming studies use standard definitions of low BMD to determine clinical implications of BMD Z-scores below 0, explore cause of low BMD in the subset of patients with low BMD for chronological age (Z-score < -2) and assess fracture risk in patients with PKU.
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Affiliation(s)
- Serwet Demirdas
- Department of Paediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| | - Katie E Coakley
- Nutrition and Health Sciences and Molecules to Mankind Programs, Laney Graduate School and Department of Human Genetics, Emory University, Atlanta, GA, USA.
| | - Peter H Bisschop
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| | - Carla E M Hollak
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| | - Annet M Bosch
- Department of Paediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| | - Rani H Singh
- Metabolic Nutrition and Genetics Program Department of Human Genetics, Emory University Atlanta GA United States, Atlanta, GA, USA.
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Engineering and kinetic stabilization of the therapeutic enzyme Anabeana variabilis phenylalanine ammonia lyase. Appl Biochem Biotechnol 2013; 171:1805-18. [PMID: 23999738 DOI: 10.1007/s12010-013-0450-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 08/15/2013] [Indexed: 10/26/2022]
Abstract
Anabeana variabilis phenylalanine ammonia lyase has just recently been discovered and introduced in clinical trials of phenylketonuria enzyme replacement therapy for its outstanding kinetic properties. In the present study, kinetic stabilization of this therapeutically important enzyme has been explored by introduction of a disulfide bond into the structure. Site-directed mutagenesis was performed with quick-change PCR method. Recombinant wild-type and mutated enzymes were expressed in Escherichia coli, and his-tagged proteins were affinity purified. Formation of disulfide bond was confirmed by Ellman's method, and then chemical unfolding, kinetic behavior, and thermal inactivation of mutated enzyme were compared with the wild type. Based on our results, the Q292C mutation resulted in a significant improvement in kinetic stability and resistance against chemical unfolding of the enzyme while kinetic parameters and pH profile of enzyme activity were remained unaffected. The results of the present study provided an insight towards designing phenylalanine ammonia lyases with higher stability.
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Dos Reis EA, Rieger E, de Souza SS, Rasia-Filho AA, Wannmacher CMD. Effects of a co-treatment with pyruvate and creatine on dendritic spines in rat hippocampus and posterodorsal medial amygdala in a phenylketonuria animal model. Metab Brain Dis 2013; 28:509-17. [PMID: 23430365 DOI: 10.1007/s11011-013-9389-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 02/11/2013] [Indexed: 12/13/2022]
Abstract
Phenylketonuria (PKU) is the most frequent aminoacidopathy that damage the central nervous system and is characterized by neural injury, mental retardation and accumulation of phenylalanine and its metabolites in plasma and tissues. So far, the only effective protection against brain injury is the administration of special phenylalanine-free diets. Animals with lesions in the hippocampus and amygdala had behavioral impairments indicating the importance of the integrity of these brain structures in learning and memory tasks which are disability characteristics of patients affected by PKU. In the present study we aimed to test the effect of the combination of two energetic and antioxidant compounds-pyruvate and creatine (intraperitoneal injections of 0.2 mg/g of body weight and 0.4 mg/g of body weight, respectively, treatment from the 7th to the 28th postnatal day)-in animals subjected to a chronic model of PKU. To assess likely effects, the density of dendritic spines in the hippocampal CA1 region and in the posterodorsal medial amygdala of 60-day-old male rats were analyzed under confocal microscopy. Present results showed that the co-treatment with pyruvate and creatine prevented the reduction in dendritic spine density in the stratum radiatum of the CA1 hippocampal field and in the posterodorsal medial amygdala of PKU animals. If this can also occur in PKU patients, it is possible that creatine and pyruvate may help to prevent brain damage in patients under specific diet.
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Affiliation(s)
- Eleonora Araújo Dos Reis
- Departamento de Bioquímica, Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
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Robertson LV, McStravick N, Ripley S, Weetch E, Donald S, Adam S, Micciche A, Boocock S, MacDonald A. Body mass index in adult patients with diet-treated phenylketonuria. J Hum Nutr Diet 2013; 26 Suppl 1:1-6. [PMID: 23551621 DOI: 10.1111/jhn.12054] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND There is an increasing number of adults with phenylketonuria (PKU) on a low phenylalanine diet. In the general population, an increasing body mass index (BMI) in the UK is a major problem with associated co-morbidities. The present study aimed to identify whether patients with diet-treated PKU have obesity rates comparable to those in the general population. METHODS Two hundred and thirty-six PKU subjects (49% male, 51% female), aged >16 years, who were diagnosed by newborn screening and were receiving a low phenylalanine diet, were identified from seven metabolic centres in the UK. Retrospective data were collated on age, sex, BMI and mean phenylalanine concentration over the previous 12 months. RESULTS Mean (SD) phenylalanine concentration for all 236 subjects was 789 (311) μm; mean (SD) BMI was 26 (5.4) kg m(-2) [males 25 (4.3) kg m(-2) , females 27 (6.2) kg m(-2) ]; mean (SD) age was 26 (7) years; and 55% had a BMI > 25 kg m(-2) . The percentage of subjects with a BMI >25 kg m(-2) and >30 kg m(-2) , as well as increasing obesity with age, was similar to the UK population. A correlation was observed between increasing BMI and a higher phenylalanine concentration (r = 0.243, P = 0.001). CONCLUSIONS The number of overweight and obese patients with diet-treated PKU in the UK is a concern. This could lead to other obesity-related complications increasing the complexity of diet and the cost of their care. There is a need to educate patients with respect to adopting a healthy, low phenylalanine diet and lifestyle to prevent further rises in BMI.
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Affiliation(s)
- L V Robertson
- University Hospitals Birmingham NHS Foundation Trust, Old Queen Elizabeth Hospital, Birmingham, UK.
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Van Calcar SC, Ney DM. Food products made with glycomacropeptide, a low-phenylalanine whey protein, provide a new alternative to amino Acid-based medical foods for nutrition management of phenylketonuria. J Acad Nutr Diet 2012; 112:1201-10. [PMID: 22818728 PMCID: PMC3402906 DOI: 10.1016/j.jand.2012.05.004] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Accepted: 04/10/2012] [Indexed: 02/06/2023]
Abstract
Phenylketonuria (PKU), an inborn error in phenylalanine metabolism, requires lifelong nutrition management with a low-phenylalanine diet, which includes a phenylalanine-free amino acid-based medical formula to provide the majority of an individual's protein needs. Compliance with this diet is often difficult for older children, adolescents, and adults with PKU. The whey protein glycomacropeptide (GMP) is ideally suited for the PKU diet because it is naturally low in phenylalanine. Nutritionally complete, acceptable medical foods and beverages can be made with GMP to increase the variety of protein sources for the PKU diet. As an intact protein, GMP improves protein use and increases satiety compared with amino acids. Thus, GMP provides a new, more physiologic source of low-phenylalanine dietary protein for people with PKU.
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Affiliation(s)
- Sandra C. Van Calcar
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Senior Metabolic Dietitian, Biochemical Genetics Program, Waisman Center, University of Wisconsin-Madison, 1500 Highland Ave., Madison, WI 53705, Phone: 608-263-5981, Fax: 608-263-0530
| | - Denise M. Ney
- Billings Bascom Professor, Department of Nutritional Sciences and Waisman Center, University of Wisconsin-Madison, 1415 Linden Drive, Madison, WI 53703, Phone: 608-262-4386, Fax: 608-262-5860
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Lindegren ML, Krishnaswami S, Reimschisel T, Fonnesbeck C, Sathe NA, McPheeters ML. A Systematic Review of BH4 (Sapropterin) for the Adjuvant Treatment of Phenylketonuria. JIMD Rep 2012; 8:109-19. [PMID: 23430527 DOI: 10.1007/8904_2012_168] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Revised: 06/20/2012] [Accepted: 07/04/2012] [Indexed: 12/04/2022] Open
Abstract
CONTEXT Dietary management is the mainstay of effective treatment in PKU, but dietary restriction is difficult and additional treatment options are needed. OBJECTIVE To systematically review evidence regarding sapropterin (BH4) use as an adjunct to dietary restriction in individuals with PKU. DATA SOURCES Five databases including MEDLINE up to August 2011. STUDY SELECTION Two reviewers independently assessed studies against predetermined inclusion/exclusion criteria. DATA EXTRACTION Two reviewers independently extracted data regarding participant and intervention characteristics and outcomes and assigned overall quality and strength of evidence ratings based on predetermined criteria. RESULTS BH4 research includes two randomized controlled trials (RCTs) and three uncontrolled open-label trials. Phenylalanine (Phe) levels were reduced by at least 30 % in up to half of treated participants (32-50 %). In one RCT comparing placebo on likelihood of a 30 % reduction in Phe, 9 % of those on placebo achieved this effect, compared with 44 % of the treated group after 6 weeks. Phe tolerance and variability were improved in treated participants in studies assessing those outcomes. No comparative studies assessed long-term outcomes including cognitive effects, nutritional status, or quality of life. CONCLUSIONS Adjuvant pharmacologic therapy has the potential to support individuals in achieving optimal Phe levels. BH4 has been shown to reduce Phe levels in some individuals, with significantly greater reductions seen in treated versus placebo groups. The strength of the evidence is moderate for short-term effects on reducing Phe in a subset of initially BH4-responsive individuals, moderate for a lack of significant harms, low for longer-term effects on cognition, and insufficient for all other outcomes.
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Affiliation(s)
- Mary Lou Lindegren
- Division of General Pediatrics and Vanderbilt Institute for Global Health, Vanderbilt Medical Center, 2200 Children's Way, 8232 Doctors' Office Tower, Nashville, TN, 37232-9225, USA,
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Phenylketonuria: nutritional advances and challenges. Nutr Metab (Lond) 2012; 9:7. [PMID: 22305125 PMCID: PMC3395819 DOI: 10.1186/1743-7075-9-7] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Accepted: 02/03/2012] [Indexed: 01/26/2023] Open
Abstract
Despite the appearance of new treatment, dietary approach remains the mainstay of PKU therapy. The nutritional management has become complex to optimize PKU patients' growth, development and diet compliance. This paper review critically new advances and challenges that have recently focused attention on potential relevant of LCPUFA supplementation, progress in protein substitutes and new protein sources, large neutral amino acids and sapropterin. Given the functional effects, DHA is conditionally essential substrates that should be supplied with PKU diet in infancy but even beyond. An European Commission Programme is going on to establish quantitative DHA requirements in this population. Improvements in the palatability, presentation, convenience and nutritional composition of protein substitutes have helped to improve long-term compliance with PKU diet, although it can be expected for further improvement in this area. Glycomacropeptide, a new protein source, may help to support dietary compliance of PKU subject but further studies are needed to evaluate this metabolic and nutritional issues. The PKU diet is difficult to maintain in adolescence and adult life. Treatment with large neutral amino acids or sapropterin in selected cases can be helpful. However, more studies are necessary to investigate the potential role, dose, and composition of large neutral amino acids in PKU treatment and to show long-term efficacy and tolerance. Ideally treatment with sapropterin would lead to acceptable blood Phe control without dietary treatment but this is uncommon and sapropterin will usually be given in combination with dietary treatment, but clinical protocol evaluating adjustment of PKU diet and sapropterin dosage are needed. In conclusion PKU diet and the new existing treatments, that need to be optimized, may be a complete and combined strategy possibly positive impacting on the psychological, social, and neurocognitive life of PKU patients.
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