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Xia W, Zhang M, Liu C, Wang S, Xu A, Xia Z, Pang L, Cai Y. Exploring the therapeutic potential of tetrahydrobiopterin for heart failure with preserved ejection fraction: A path forward. Life Sci 2024; 345:122594. [PMID: 38537900 DOI: 10.1016/j.lfs.2024.122594] [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: 01/17/2024] [Revised: 03/10/2024] [Accepted: 03/24/2024] [Indexed: 04/02/2024]
Abstract
A large number of patients are affected by classical heart failure (HF) symptomatology with preserved ejection fraction (HFpEF) and multiorgan syndrome. Due to high morbidity and mortality rate, hospitalization and mortality remain serious socioeconomic problems, while the lack of effective pharmacological or device treatment means that HFpEF presents a major unmet medical need. Evidence from clinical and basic studies demonstrates that systemic inflammation, increased oxidative stress, and impaired mitochondrial function are the common pathological mechanisms in HFpEF. Tetrahydrobiopterin (BH4), beyond being an endogenous co-factor for catalyzing the conversion of some essential biomolecules, has the capacity to prevent systemic inflammation, enhance antioxidant resistance, and modulate mitochondrial energy production. Therefore, BH4 has emerged in the last decade as a promising agent to prevent or reverse the progression of disorders such as cardiovascular disease. In this review, we cover the clinical progress and limitations of using downstream targets of nitric oxide (NO) through NO donors, soluble guanylate cyclase activators, phosphodiesterase inhibitors, and sodium-glucose co-transporter 2 inhibitors in treating cardiovascular diseases, including HFpEF. We discuss the use of BH4 in association with HFpEF, providing new evidence for its potential use as a pharmacological option for treating HFpEF.
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Affiliation(s)
- Weiyi Xia
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong SAR, China
| | - Miao Zhang
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong SAR, China; Shenzhen Second People's Hospital, First Affiliated Hospital of Shenzhen University, Guangdong, China
| | - Chang Liu
- Department of Anesthesiology, The First Hospital of Jilin University, Jilin, China
| | - Sheng Wang
- Department of Anesthesiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - Aimin Xu
- State Key Laboratory of Pharmaceutical Biotechnology, The University of Hong Kong, Hong Kong SAR, China; Department of Medicine, The University of Hong Kong, Hong Kong SAR, China; Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong SAR, China
| | - Zhengyuan Xia
- Department of Anesthesiology, Affiliated Hospital of Guangdong Medical University, Guangdong, China
| | - Lei Pang
- Department of Anesthesiology, The First Hospital of Jilin University, Jilin, China.
| | - Yin Cai
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong SAR, China; Research Center for Chinese Medicine Innovation, The Hong Kong Polytechnic University, Hong Kong SAR, China; Research Institute for Future Food, The Hong Kong Polytechnic University, Hong Kong SAR, China.
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2
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Jiang X, Shao Y, Liao Y, Zheng X, Peng M, Cai Y, Wang M, Liu H, Zeng C, Lin Y, Zhang W, Liu L. Mechanisms underlying the efficacy and limitation of dopa and tetrahydrobiopterin therapies for the deficiency of GTP cyclohydrolase 1 revealed in a novel mouse model. Eur J Pharmacol 2024; 967:176379. [PMID: 38342361 DOI: 10.1016/j.ejphar.2024.176379] [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: 09/24/2023] [Revised: 01/31/2024] [Accepted: 01/31/2024] [Indexed: 02/13/2024]
Abstract
Dopa and tetrahydrobiopterin (BH4) supplementation are recommended therapies for the dopa-responsive dystonia caused by GTP cyclohydrolase 1 (GCH1, also known as GTPCH) deficits. However, the efficacy and mechanisms of these therapies have not been intensively studied yet. In this study, we tested the efficacy of dopa and BH4 therapies by using a novel GTPCH deficiency mouse model, Gch1KI/KI, which manifested infancy-onset motor deficits and growth retardation similar to the patients. First, dopa supplementation supported Gch1KI/KI mouse survival to adulthood, but residual motor deficits and dwarfism remained. Interestingly, RNAseq analysis indicated that while the genes participating in BH4 biosynthesis and regeneration were significantly increased in the liver, no significant changes were observed in the brain. Second, BH4 supplementation alone restored the growth of Gch1KI/KI pups only in early postnatal developmental stage. High doses of BH4 supplementation indeed restored the total brain BH4 levels, but brain dopamine deficiency remained. While total brain TH levels were relatively increased in the BH4 treated Gch1KI/KI mice, the TH in the striatum were still almost undetectable, suggesting differential BH4 requirements among brain regions. Last, the growth of Gch1KI/KI mice under combined therapy outperformed dopa or BH4 therapy alone. Notably, dopamine was abnormally high in more than half, but not all, of the treated Gch1KI/KI mice, suggesting the existence of variable synergetic effects of dopa and BH4 supplementation. Our results provide not only experimental evidence but also novel mechanistic insights into the efficacy and limitations of dopa and BH4 therapies for GTPCH deficiency.
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Affiliation(s)
- Xiaoling Jiang
- Department of Genetics and Endocrine, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, 510623, China
| | - Yongxian Shao
- Department of Genetics and Endocrine, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, 510623, China
| | - Yongqiang Liao
- Department of Genetics and Endocrine, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, 510623, China
| | - Xiaoning Zheng
- Department of Genetics and Endocrine, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, 510623, China
| | - Minzhi Peng
- Department of Genetics and Endocrine, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, 510623, China
| | - Yanna Cai
- Department of Genetics and Endocrine, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, 510623, China
| | - Meiyi Wang
- Department of Genetics and Endocrine, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, 510623, China
| | - Huazhen Liu
- Department of Genetics and Endocrine, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, 510623, China
| | - Chunhua Zeng
- Department of Genetics and Endocrine, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, 510623, China
| | - Yunting Lin
- Department of Genetics and Endocrine, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, 510623, China.
| | - Wen Zhang
- Department of Genetics and Endocrine, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, 510623, China.
| | - Li Liu
- Department of Genetics and Endocrine, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, 510623, China.
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Fujihara Y, Kodo Y, Miyoshi SI, Watanabe R, Toyoda H, Mankura M, Kabuto H, Takayama F. Spirulina platensis and its ingredient biopterin glucoside improved insulin sensitivity in non-alcoholic steatohepatitis model. J Clin Biochem Nutr 2021; 69:151-157. [PMID: 34616107 PMCID: PMC8482380 DOI: 10.3164/jcbn.20-201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 12/25/2020] [Indexed: 11/25/2022] Open
Abstract
Non-alcoholic steatohepatitis is the chronic liver disease leading to cirrhosis and cancer and its prevalence is increasing. Some agents are under clinical trials for non-alcoholic steatohepatitis treatment. We previously reported Spirulina (Arthrospira) platensis effectively prevented non-alcoholic steatohepatitis progression in our model rats. The contribution of phycocyanin, an ingredient of Spirulina (Arthrospira) platensis, was limited. We, therefore, have looked for more active components of Spirulina (Arthrospira) platensis. In this study, we pursued the effect of biopterin glucoside, another bioactive ingredient of Spirulina (Arthrospira) platensis. We found Spirulina (Arthrospira) platensis and biopterin glucoside oral administrations effectively alleviated oxidative stress, inflammation and insulin signal failure, and prevented fibroblast growth factor 21 gene overexpression in non-alcoholic steatohepatitis rat livers. We concluded biopterin glucoside is a major component of Spirulina (Arthrospira) platensis action.
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Affiliation(s)
- Yuri Fujihara
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Yasumasa Kodo
- Spirulina BioLab. Co., Ltd., 1-13-6 Nishinakajima, Yodogawa-ku, Osaka 532-0011, Japan
| | - Shin-Ichi Miyoshi
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Ritsuko Watanabe
- Okayama Kyoritsu General Hospital, 8-10 Akasakahonmachi, Naka-ku, Okayama 703-8288, Japan
| | - Hiroshi Toyoda
- Okayama Kyoritsu General Hospital, 8-10 Akasakahonmachi, Naka-ku, Okayama 703-8288, Japan
| | - Mitsumasa Mankura
- Kurashiki Sakuyo University, 3515 Tamashima Nagao, Kurashiki, Okayama 710-0292, Japan
| | - Hideaki Kabuto
- Kagawa Prefectural College of Health Sciences, 281-1 Murechohara, Takamatsu, Kagawa 761-0123, Japan
| | - Fusako Takayama
- Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
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4
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Fanet H, Capuron L, Castanon N, Calon F, Vancassel S. Tetrahydrobioterin (BH4) Pathway: From Metabolism to Neuropsychiatry. Curr Neuropharmacol 2021; 19:591-609. [PMID: 32744952 PMCID: PMC8573752 DOI: 10.2174/1570159x18666200729103529] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 07/03/2020] [Accepted: 07/23/2020] [Indexed: 11/22/2022] Open
Abstract
Tetrahydrobipterin (BH4) is a pivotal enzymatic cofactor required for the synthesis of serotonin, dopamine and nitric oxide. BH4 is essential for numerous physiological processes at periphery and central levels, such as vascularization, inflammation, glucose homeostasis, regulation of oxidative stress and neurotransmission. BH4 de novo synthesis involves the sequential activation of three enzymes, the major controlling point being GTP cyclohydrolase I (GCH1). Complementary salvage and recycling pathways ensure that BH4 levels are tightly kept within a physiological range in the body. Even if the way of transport of BH4 and its ability to enter the brain after peripheral administration is still controversial, data showed increased levels in the brain after BH4 treatment. Available evidence shows that GCH1 expression and BH4 synthesis are stimulated by immunological factors, notably pro-inflammatory cytokines. Once produced, BH4 can act as an anti- inflammatory molecule and scavenger of free radicals protecting against oxidative stress. At the same time, BH4 is prone to autoxidation, leading to the release of superoxide radicals contributing to inflammatory processes, and to the production of BH2, an inactive form of BH4, reducing its bioavailability. Alterations in BH4 levels have been documented in many pathological situations, including Alzheimer's disease, Parkinson's disease and depression, in which increased oxidative stress, inflammation and alterations in monoaminergic function are described. This review aims at providing an update of the knowledge about metabolism and the role of BH4 in brain function, from preclinical to clinical studies, addressing some therapeutic implications.
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Affiliation(s)
- H. Fanet
- INRAe, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- Université de Bordeaux, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- Faculty of Pharmacy, Université Laval, Quebec City, QC, Canada
- Neurosciences Axis, Centre de Recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada
- OptiNutriBrain International Associated Laboratory (NurtriNeuro France-INAF Canada), Quebec City, Canada
| | - L. Capuron
- INRAe, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- Université de Bordeaux, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- OptiNutriBrain International Associated Laboratory (NurtriNeuro France-INAF Canada), Quebec City, Canada
| | - N. Castanon
- INRAe, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- Université de Bordeaux, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- OptiNutriBrain International Associated Laboratory (NurtriNeuro France-INAF Canada), Quebec City, Canada
| | - F. Calon
- Faculty of Pharmacy, Université Laval, Quebec City, QC, Canada
- Neurosciences Axis, Centre de Recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada
- OptiNutriBrain International Associated Laboratory (NurtriNeuro France-INAF Canada), Quebec City, Canada
| | - S. Vancassel
- INRAe, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- Université de Bordeaux, Nutrition and Integrated Neurobiology, UMR 1286, Bordeaux, France
- OptiNutriBrain International Associated Laboratory (NurtriNeuro France-INAF Canada), Quebec City, Canada
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5
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Evers RAF, van Vliet D, van Spronsen FJ. Tetrahydrobiopterin treatment in phenylketonuria: A repurposing approach. J Inherit Metab Dis 2020; 43:189-199. [PMID: 31373030 DOI: 10.1002/jimd.12151] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 07/01/2019] [Accepted: 07/04/2019] [Indexed: 12/24/2022]
Abstract
In phenylketonuria (PKU) patients, early diagnosis by neonatal screening and immediate institution of a phenylalanine-restricted diet can prevent severe intellectual impairment. Nevertheless, outcome remains suboptimal in some patients asking for additional treatment strategies. Tetrahydrobiopterin (BH4 ) could be one of those treatment options, as it may not only increase residual phenylalanine hydroxylase activity in BH4 -responsive PKU patients, but possibly also directly improves neurocognitive functioning in both BH4 -responsive and BH4 -unresponsive PKU patients. In the present review, we aim to further define the theoretical working mechanisms by which BH4 might directly influence neurocognitive functioning in PKU having passed the blood-brain barrier. Further research should investigate which of these mechanisms are actually involved, and should contribute to the development of an optimal BH4 treatment regimen to directly improve neurocognitive functioning in PKU. Such possible repurposing approach of BH4 treatment in PKU may improve neuropsychological outcome and mental health in both BH4 -responsive and BH4 -unresponsive PKU patients.
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Affiliation(s)
- Roeland A F Evers
- Division of Metabolic Diseases, University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, Groningen, The Netherlands
| | - Danique van Vliet
- Division of Metabolic Diseases, University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, Groningen, The Netherlands
| | - Francjan J van Spronsen
- Division of Metabolic Diseases, University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, Groningen, The Netherlands
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Ohashi A, Mamada K, Harada T, Naito M, Takahashi T, Aizawa S, Hasegawa H. Organic anion transporters, OAT1 and OAT3, are crucial biopterin transporters involved in bodily distribution of tetrahydrobiopterin and exclusion of its excess. Mol Cell Biochem 2017; 435:97-108. [PMID: 28534121 PMCID: PMC5632347 DOI: 10.1007/s11010-017-3060-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 05/04/2017] [Indexed: 01/05/2023]
Abstract
Tetrahydrobiopterin (BH4) is a common coenzyme of phenylalanine-, tyrosine-, and tryptophan hydroxylases, alkylglycerol monooxygenase, and NO synthases (NOS). Synthetic BH4 is used medicinally for BH4-responsive phenylketonuria and inherited BH4 deficiency. BH4 supplementation has also drawn attention as a therapy for various NOS-related cardio-vascular diseases, but its use has met with limited success in decreasing BH2, the oxidized form of BH4. An increase in the BH2/BH4 ratio leads to NOS dysfunction. Previous studies revealed that BH4 supplementation caused a rapid urinary loss of BH4 accompanied by an increase in the blood BH2/BH4 ratio and an involvement of probenecid-sensitive but unknown transporters was strongly suggested in these processes. Here we show that OAT1 and OAT3 enabled cells to take up BP (BH4 and/or BH2) in a probenecid-sensitive manner using rat kidney slices and transporter-expressing cell systems, LLC-PK1 cells and Xenopus oocytes. Both OAT1 and OAT3 preferred BH2 and sepiapterin as their substrate roughly 5- to 10-fold more than BH4. Administration of probenecid acutely reduced the urinary exclusion of endogenous BP accompanied by a rise in blood BP in vivo. These results indicated that OAT1 and OAT3 played crucial roles: (1) in determining baseline levels of blood BP by excluding endogenous BP through the urine, (2) in the rapid distribution to organs of exogenous BH4 and the exclusion to urine of a BH4 excess, particularly when BH4 was administered, and (3) in scavenging blood BH2 by cellular uptake as the gateway to the salvage pathway of BH4, which reduces BH2 back to BH4.
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Affiliation(s)
- Akiko Ohashi
- Department of Anatomy, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda, Tokyo, 101-8310, Japan.
- Division of Functional Morphology, Dental Research Center, Nihon University School of Dentistry, Chiyoda, Tokyo, 101-8310, Japan.
| | - Kaori Mamada
- Department of Biosciences, Teikyo University of Science and Technology, Uenohara, Yamanashi, 401-0193, Japan
| | - Tomonori Harada
- Division of Anatomical Science, Department of Functional Morphology, Nihon University School of Medicine, Itabashi, Tokyo, 173-8610, Japan
| | - Masako Naito
- Department of Anatomy, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda, Tokyo, 101-8310, Japan
- Division of Functional Morphology, Dental Research Center, Nihon University School of Dentistry, Chiyoda, Tokyo, 101-8310, Japan
| | - Tomihisa Takahashi
- Department of Anatomy, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda, Tokyo, 101-8310, Japan
- Division of Functional Morphology, Dental Research Center, Nihon University School of Dentistry, Chiyoda, Tokyo, 101-8310, Japan
| | - Shin Aizawa
- Division of Anatomical Science, Department of Functional Morphology, Nihon University School of Medicine, Itabashi, Tokyo, 173-8610, Japan
| | - Hiroyuki Hasegawa
- Department of Anatomy, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda, Tokyo, 101-8310, Japan
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Ohashi A, Saeki Y, Harada T, Naito M, Takahashi T, Aizawa S, Hasegawa H. Tetrahydrobiopterin Supplementation: Elevation of Tissue Biopterin Levels Accompanied by a Relative Increase in Dihydrobiopterin in the Blood and the Role of Probenecid-Sensitive Uptake in Scavenging Dihydrobiopterin in the Liver and Kidney of Rats. PLoS One 2016; 11:e0164305. [PMID: 27711248 PMCID: PMC5053593 DOI: 10.1371/journal.pone.0164305] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 09/22/2016] [Indexed: 12/21/2022] Open
Abstract
Tetrahydrobiopterin (BH4) is an essential cofactor of nitric oxide synthase (NOS) and aromatic amino acid hydroxylases. BH4 and 7,8-dihydrobiopterin (BH2) are metabolically interchangeable at the expense of NADPH. Exogenously administered BH4 can be metabolized by the body, similar to vitamins. At present, synthetic BH4 is used as an orphan drug for patients with inherited diseases requiring BH4 supplementation. BH4 supplementation has also drawn attention as a means of treating certain cardiovascular symptoms, however, its application in human patients remains limited. Here, we tracked biopterin (BP) distribution in blood, bile, urine, liver, kidney and brain after BH4 administration (5 mg/kg rat, i.v.) with or without prior treatment with probenecid, a potent inhibitor of uptake transporters particularly including organic anion transporter families such as OTA1 and OAT3. The rapid excretion of BP in urine was driven by elevated blood concentrations and its elimination reached about 90% within 120 min. In the very early period, BP was taken up by the liver and kidney and gradually released back to the blood. BH4 administration caused a considerable decrease in the BH4% in blood BP as an inevitable compensatory process. Probenecid treatment slowed down the decrease in blood BP and simultaneously inhibited its initial rapid excretion in the kidney. At the same time, the BH4% was further lowered, suggesting that the probenecid-sensitive BP uptake played a crucial role in BH2 scavenging in vivo. This suggested that the overproduced BH2 was taken up by organs by means of the probenecid-sensitive process, and was then scavenged by counter-conversion to BH4 via the BH4 salvage pathway. Taken together, BH4 administration was effective at raising BP levels in organs over the course of hours but with extremely low efficiency. Since a high BH2 relative to BH4 causes NOS dysfunction, the lowering of the BH4% must be avoided in practice, otherwise the desired effect of the supplementation in ameliorating NOS dysfunction would be spoiled.
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Affiliation(s)
- Akiko Ohashi
- Department of Anatomy, Nihon University School of Dentistry, Chiyoda, Tokyo, Japan
| | - Yusuke Saeki
- Department of Biosciences, Teikyo University of Science and TechnologyUenohara, Yamanashi, Japan
| | - Tomonori Harada
- Division of Anatomical Science, Department of Functional Morphology, Nihon University School of Medicine, Itabashi, Tokyo, Japan
| | - Masako Naito
- Department of Anatomy, Nihon University School of Dentistry, Chiyoda, Tokyo, Japan
| | - Tomihisa Takahashi
- Department of Anatomy, Nihon University School of Dentistry, Chiyoda, Tokyo, Japan
| | - Shin Aizawa
- Division of Anatomical Science, Department of Functional Morphology, Nihon University School of Medicine, Itabashi, Tokyo, Japan
| | - Hiroyuki Hasegawa
- Department of Anatomy, Nihon University School of Dentistry, Chiyoda, Tokyo, Japan
- Division of Anatomical Science, Department of Functional Morphology, Nihon University School of Medicine, Itabashi, Tokyo, Japan
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Yeo TW, Lampah DA, Kenangalem E, Tjitra E, Price RN, Weinberg JB, Hyland K, Granger DL, Anstey NM. Impaired systemic tetrahydrobiopterin bioavailability and increased dihydrobiopterin in adult falciparum malaria: association with disease severity, impaired microvascular function and increased endothelial activation. PLoS Pathog 2015; 11:e1004667. [PMID: 25764397 PMCID: PMC4357386 DOI: 10.1371/journal.ppat.1004667] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 01/07/2015] [Indexed: 12/22/2022] Open
Abstract
Tetrahydrobiopterin (BH₄) is a co-factor required for catalytic activity of nitric oxide synthase (NOS) and amino acid-monooxygenases, including phenylalanine hydroxylase. BH4 is unstable: during oxidative stress it is non-enzymatically oxidized to dihydrobiopterin (BH₂), which inhibits NOS. Depending on BH₄ availability, NOS oscillates between NO synthase and NADPH oxidase: as the BH₄/BH₂ ratio decreases, NO production falls and is replaced by superoxide. In African children and Asian adults with severe malaria, NO bioavailability decreases and plasma phenylalanine increases, together suggesting possible BH₄ deficiency. The primary three biopterin metabolites (BH₄, BH₂ and B₀ [biopterin]) and their association with disease severity have not been assessed in falciparum malaria. We measured pterin metabolites in urine of adults with severe falciparum malaria (SM; n=12), moderately-severe malaria (MSM, n=17), severe sepsis (SS; n=5) and healthy subjects (HC; n=20) as controls. In SM, urinary BH₄ was decreased (median 0.16 ¼mol/mmol creatinine) compared to MSM (median 0.27), SS (median 0.54), and HC (median 0.34)]; p<0.001. Conversely, BH₂ was increased in SM (median 0.91 ¼mol/mmol creatinine), compared to MSM (median 0.67), SS (median 0.39), and HC (median 0.52); p<0.001, suggesting increased oxidative stress and insufficient recycling of BH2 back to BH4 in severe malaria. Overall, the median BH₄/BH₂ ratio was lowest in SM [0.18 (IQR: 0.04-0.32)] compared to MSM (0.45, IQR 0.27-61), SS (1.03; IQR 0.54-2.38) and controls (0.66; IQR 0.43-1.07); p<0.001. In malaria, a lower BH₄/BH₂ ratio correlated with decreased microvascular reactivity (r=0.41; p=0.03) and increased ICAM-1 (r=-0.52; p=0.005). Decreased BH4 and increased BH₂ in severe malaria (but not in severe sepsis) uncouples NOS, leading to impaired NO bioavailability and potentially increased oxidative stress. Adjunctive therapy to regenerate BH4 may have a role in improving NO bioavailability and microvascular perfusion in severe falciparum malaria.
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Affiliation(s)
- Tsin W. Yeo
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
- Institute of Infectious Disease and Epidemiology, Tan Tock Seng Hospital, Singapore
| | - Daniel A. Lampah
- Menzies School of Health Research-National Institute of Health Research and Development Research Program, and District Ministry of Health, Timika, Papua, Indonesia
| | - Enny Kenangalem
- Menzies School of Health Research-National Institute of Health Research and Development Research Program, and District Ministry of Health, Timika, Papua, Indonesia
| | - Emiliana Tjitra
- National Institute of Health Research and Development, Jakarta, Indonesia
| | - Ric N. Price
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - J. Brice Weinberg
- Duke University and VA Medical Centers, Durham, North Carolina, United States of America
| | - Keith Hyland
- Medical Neurogenetics LLC, Atlanta, Georgia, United States of America
| | - Donald L. Granger
- Division of Infectious Diseases, University of Utah and Veterans Affairs Medical Center, Salt Lake City, Utah, United States of America
| | - Nicholas M. Anstey
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Division of Medicine, Royal Darwin Hospital, Darwin, Northern Territory, Australia
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9
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Rubach MP, Mukemba J, Florence S, Lopansri BK, Hyland K, Volkheimer AD, Yeo TW, Anstey NM, Weinberg JB, Mwaikambo ED, Granger DL. Impaired systemic tetrahydrobiopterin bioavailability and increased oxidized biopterins in pediatric falciparum malaria: association with disease severity. PLoS Pathog 2015; 11:e1004655. [PMID: 25764173 PMCID: PMC4357384 DOI: 10.1371/journal.ppat.1004655] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 01/05/2015] [Indexed: 12/17/2022] Open
Abstract
Decreased bioavailability of nitric oxide (NO) is a major contributor to the pathophysiology of severe falciparum malaria. Tetrahydrobiopterin (BH4) is an enzyme cofactor required for NO synthesis from L-arginine. We hypothesized that systemic levels of BH₄ would be decreased in children with cerebral malaria, contributing to low NO bioavailability. In an observational study in Tanzania, we measured urine levels of biopterin in its various redox states (fully reduced [BH₄] and the oxidized metabolites, dihydrobiopterin [BH₂] and biopterin [B₀]) in children with uncomplicated malaria (UM, n = 55), cerebral malaria (CM, n = 45), non-malaria central nervous system conditions (NMC, n = 48), and in 111 healthy controls (HC). Median urine BH4 concentration in CM (1.10 [IQR:0.55-2.18] μmol/mmol creatinine) was significantly lower compared to each of the other three groups - UM (2.10 [IQR:1.32-3.14];p<0.001), NMC (1.52 [IQR:1.01-2.71];p = 0.002), and HC (1.60 [IQR:1.15-2.23];p = 0.005). Oxidized biopterins were increased, and the BH4:BH2 ratio markedly decreased in CM. In a multivariate logistic regression model, each Log10-unit decrease in urine BH4 was independently associated with a 3.85-fold (95% CI:1.89-7.61) increase in odds of CM (p<0.001). Low systemic BH4 levels and increased oxidized biopterins contribute to the low NO bioavailability observed in CM. Adjunctive therapy to regenerate BH4 may have a role in improving NO bioavailability and microvascular perfusion in severe falciparum malaria.
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Affiliation(s)
- Matthew P. Rubach
- Department of Medicine, Duke University and VA Medical Centers, Durham, North Carolina, United States of America
| | - Jackson Mukemba
- Department of Pediatrics, Hubert Kairuki Memorial University, Dar es Salaam, United Republic of Tanzania
| | - Salvatore Florence
- Department of Pediatrics, Hubert Kairuki Memorial University, Dar es Salaam, United Republic of Tanzania
| | - Bert K. Lopansri
- Department of Medicine, Intermountain Healthcare, Salt Lake City, Utah, United States of America
- Department of Medicine, University of Utah School of Medicine and VA Medical Center, Salt Lake City, Utah, United States of America
| | - Keith Hyland
- Neurochemistry Division, Medical Neurogenetics, Atlanta, Georgia, United States of America
| | - Alicia D. Volkheimer
- Department of Medicine, Duke University and VA Medical Centers, Durham, North Carolina, United States of America
| | - Tsin W. Yeo
- Global and Tropical Health Division, Menzies School for Health Research and Charles Darwin University, Darwin, Australia
- Division of Medicine, Royal Darwin Hospital, Darwin, Northern Territory, Australia
- Department of Medicine, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - Nicholas M. Anstey
- Global and Tropical Health Division, Menzies School for Health Research and Charles Darwin University, Darwin, Australia
- Division of Medicine, Royal Darwin Hospital, Darwin, Northern Territory, Australia
| | - J. Brice Weinberg
- Department of Medicine, Duke University and VA Medical Centers, Durham, North Carolina, United States of America
| | - Esther D. Mwaikambo
- Department of Pediatrics, Hubert Kairuki Memorial University, Dar es Salaam, United Republic of Tanzania
| | - Donald L. Granger
- Department of Medicine, University of Utah School of Medicine and VA Medical Center, Salt Lake City, Utah, United States of America
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10
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Mortensen A, Hasselholt S, Tveden-Nyborg P, Lykkesfeldt J. Guinea pig ascorbate status predicts tetrahydrobiopterin plasma concentration and oxidation ratio in vivo. Nutr Res 2013; 33:859-67. [PMID: 24074744 DOI: 10.1016/j.nutres.2013.07.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 07/01/2013] [Accepted: 07/07/2013] [Indexed: 12/16/2022]
Abstract
Tetrahydrobiopterin (BH₄) is an essential co-factor of nitric oxide synthases and is easily oxidized to dihydrobiopterin (BH₂) which promotes endothelial nitric oxide synthase uncoupling and deleterious superoxide production. Vitamin C has been shown to improve endothelial function by different mechanisms, some involving BH₄. The hypothesis of the present study was that vitamin C status, in particular low levels, influences biopterin redox status in vivo. Like humans, the guinea pig lacks the ability to synthesize vitamin C and was therefore used as model. Seven day old animals (n = 10/group) were given a diet containing 100, 250, 500, 750, 1000, or 1500 ppm vitamin C until euthanasia at age 60-64 days. Blood samples were drawn from the heart and analyzed for ascorbate, dehydroascorbic acid (DHA), BH₄ and BH₂ by high-performance liquid chromatography. Plasma BH₄ levels were found to be significantly lower in animals fed 100 ppm vitamin C compared to all other groups (P < .05 or less). BH₂ levels were not significantly different between groups but the BH₂-to-BH₄ ratio was higher in the group fed 100 ppm vitamin C (P < .001 all cases). Significant positive correlations between BH4 and ascorbate and between BH₂-to-BH₄ ratio and DHA were observed (P < .0001 both cases). Likewise, BH₂-to-BH₄ ratio was negatively correlated with ascorbate (P < .0001) as was BH₄ and DHA (P < .005). In conclusion, the redox status of plasma biopterins, essentially involved in vasodilation, depends on the vitamin C status in vivo. Thus, ingestion of insufficient quantities of vitamin C not only leads to vitamin C deficiency but also to increased BH₄ oxidation which may promote endothelial dysfunction.
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Affiliation(s)
- Alan Mortensen
- Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
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11
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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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