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Shubitowski TB, Poll BG, Natarajan N, Pluznick JL. Short-chain fatty acid delivery: assessing exogenous administration of the microbiome metabolite acetate in mice. Physiol Rep 2019; 7:e14005. [PMID: 30810289 PMCID: PMC6391713 DOI: 10.14814/phy2.14005] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 01/21/2019] [Accepted: 01/22/2019] [Indexed: 02/06/2023] Open
Abstract
Short-chain fatty acids (SCFAs) are fermentation by-products of gut microbes which have been linked to positive effects on host physiology; the most abundant SCFA is acetate. Exogenous administration of acetate alters host metabolism, immune function, and blood pressure, making it a biologic of interest. The effects of acetate have been attributed to activation of G-protein-coupled receptors and other proteins (i.e., HDACs), often occurring at locations distant from the gut such as the pancreas or the kidney. However, due to technical difficulties and costs, studies have often delivered exogenous acetate without determining if systemic plasma acetate levels are altered. Thus, it is unclear to what extent each method of acetate delivery may alter systemic plasma acetate levels. In this study, we aimed to determine if acetate is elevated after exogenous administration by drinking water (DW), oral gavage (OG), or intraperitoneal (IP) injection, and if so, over what timecourse, to best inform future studies. Using a commercially available kit, we demonstrated that sodium acetate delivered over 21 days in DW does not elicit a measurable change in systemic acetate over baseline. However, when acetate is delivered by OG or IP injection, there are rapid, reproducible, and dose-dependent changes in plasma acetate. These studies report, for the first time, the timecourse of changes in plasma acetate following acetate administration by three common methods, and thus inform the best practices for exogenous acetate delivery.
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Affiliation(s)
| | - Brian G. Poll
- Department of PhysiologyJohns Hopkins School of MedicineBaltimoreMaryland
| | - Niranjana Natarajan
- Department of Stem Cell and Regenerative BiologyHarvard Stem Cell InstituteHarvard UniversityCambridgeMassachusetts
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Li B, Zhao J, Lv J, Tang F, Liu L, Sun Z, Wang L, Siwela SP, Wang Y, Song Y, Manchishi SM, Cui R. Additive antidepressant-like effects of fasting with imipramine via modulation of 5-HT2 receptors in the mice. Prog Neuropsychopharmacol Biol Psychiatry 2014; 48:199-206. [PMID: 24036107 DOI: 10.1016/j.pnpbp.2013.08.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 08/20/2013] [Accepted: 08/30/2013] [Indexed: 01/02/2023]
Abstract
Recently, studies show that intermittent fasting and caloric restriction may improve symptoms of depression. However, there is little scientific evidence regarding the literature on the antidepressant-like effects of acute fasting. The present study aims to investigate the antidepressant-like effects and its influence on brain levels of the transcription factor cAMP response element-binding protein (CREB) and its phosphorylated form (p-CREB) in different time periods of fasting mice. Furthermore, the additive antidepressant-like effects of fasting with imipramine and the possible involvement of the 5-HT2 receptors were examined. In the present study 9h, but not 3h and 18h of fasting significantly reduced immobility time in the forced swimming test (FST) without alteration in locomotor activity in the open field test. 9h fasting also enhanced the ratio of p-CREB/CREB in the frontal cortex and hippocampus. Co-administration of 9h of fasting and imipramine (30mg/kg, i.p) produced the additive antidepressant-like effects in the FST and increased the ratio of p-CREB/CREB. Meanwhile, the additive effects were partially reversed by treatment with a 5-HT2A/2C receptor agonist, (±)-1-(2, 5-dimethoxy-4-iodophenyl)-2-aminopropane hydrochloride (DOI) (5mg/kg, s.c). Furthermore, the antidepressant-like effects of 9h fasting was also blocked by DOI compared to the non-fasting control group. Serum corticosterone level, but not 5-HT and noradrenaline, was significantly increased in a time-dependent manner following different time periods of fasting. Taken together, these results suggest that acute fasting produces antidepressant-like effects via enhancement of the p-CREB/CREB ratio, and additive antidepressant-like effects of fasting with imipramine may be related to modulating 5-HT2 receptors.
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Herrera AS, Casanova JP, Gatica RI, Escobar F, Fuentealba JA. Clozapine pre-treatment has a protracted hypolocomotor effect on the induction and expression of amphetamine sensitization. Prog Neuropsychopharmacol Biol Psychiatry 2013; 47:1-6. [PMID: 23954739 DOI: 10.1016/j.pnpbp.2013.07.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 07/12/2013] [Accepted: 07/31/2013] [Indexed: 11/25/2022]
Abstract
Amphetamine locomotor sensitization is an animal model for the study of addiction and schizophrenia. The antipsychotic clozapine blocks the hyperlocomotion induced by an acute injection of amphetamine, but its effect on locomotor sensitization after repeated amphetamine administration remains unknown. In the present study we investigate the effect of repeated administration of clozapine on the induction and expression of amphetamine locomotor sensitization. We propose that repeated administration of clozapine blocks the induction and expression of amphetamine sensitization. Male Sprague-Dawley rats were classified according to their locomotor response to an acute saline injection in high responder saline (HRS) or low responder saline (LRS). Rats from both groups were injected once daily with amphetamine for 5 consecutive days. Horizontal locomotor activity was measured during 40 min. Four days after the last injection, an acute dose of amphetamine was administered to assess the expression of sensitization. Clozapine was injected once daily for 4 consecutive days before (pre-treatment) or after (treatment) induction of sensitization. Pre-treatment with clozapine significantly decreases both acute amphetamine-induced hyperlocomotion and the induction and expression of amphetamine sensitization only in LRS rats, showing a protracted hypolocomotor effect. On the other hand, clozapine treatment had no effect over locomotor response on the expression of amphetamine sensitization in either LRS or HRS rats. These data suggest that clozapine effect on amphetamine locomotor response depends on individual differences. Also, our results suggest that clozapine pre-treatment attenuates the neuroplasticity underlying amphetamine sensitization, but clozapine treatment is unable to reverse these changes once amphetamine sensitization has been induced.
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Affiliation(s)
- Andrea Susana Herrera
- Department of Pharmacy, Faculty of Chemistry, Pontificia Universidad Católica de Chile, Santiago, Chile; Millennium Science Nucleus in Stress and Addiction, Pontificia Universidad Católica de Chile, Santiago, Chile
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Alavizadeh SH, Hosseinzadeh H. Bioactivity assessment and toxicity of crocin: a comprehensive review. Food Chem Toxicol 2013; 64:65-80. [PMID: 24275090 DOI: 10.1016/j.fct.2013.11.016] [Citation(s) in RCA: 224] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 11/09/2013] [Accepted: 11/13/2013] [Indexed: 01/01/2023]
Abstract
Since ancient times, saffron, the dried stigma of the plant Crocus sativus L. has been extensively used as a spice and food colorant; in folk medicine it has been reputed to be efficacious for the alleviation and treatment of ailments. In addition to the three founded major constituents including crocin, picrocrocin and safranal, presence of carotenoids, carbohydrates, proteins, anthocyanins, vitamins and minerals provide valuable insights into the health benefits and nutritional value of saffron. Of the carotenoids present in saffron, highly water-soluble crocin (mono and diglycosyl esters of a polyene dicarboxylic acid, named crocetin) is responsible for the majority of its color, and appears to possess various health-promoting properties, as an antioxidant, antitumor, memory enhancer, antidepressant, anxiolytic and aphrodisiac. It is also worth noting that the crocin principle of saffron exhibited high efficacy along with no major toxicity in experimental models. We would be remiss to not consider the great potential of saffron and crocin, which benefits the cuisine and health of human life throughout the world. The present study provides a comprehensive and updated report of empirical investigations on bioactivities and biological characteristics of crocin.
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Affiliation(s)
| | - Hossein Hosseinzadeh
- Pharmaceutical Research Center, Department of Pharmacodynamy and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
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Nakamura Y, Sato T, Shiimura Y, Miura Y, Kojima M. FABP3 and brown adipocyte-characteristic mitochondrial fatty acid oxidation enzymes are induced in beige cells in a different pathway from UCP1. Biochem Biophys Res Commun 2013; 441:42-6. [PMID: 24129192 DOI: 10.1016/j.bbrc.2013.10.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 10/04/2013] [Indexed: 11/19/2022]
Abstract
Cold exposure and β3-adrenergic receptor agonist (CL316,243) treatment induce the production of beige cells, which express brown adipocytes(BA)-specific UCP1 protein, in white adipose tissue (WAT). It remains unclear whether the beige cells, which have different gene expression patterns from BA, express BA-characteristic fatty acid oxidation (FAO) proteins. Here we found that 5 day cold exposure and CL316,243 treatment of WAT, but not CL316,243 treatment of primary adipocytes of C57BL/6J mice, increased mRNA levels of BA-characteristic FAO proteins. These results suggest that BA-characteristic FAO proteins are induced in beige cells in a different pathway from UCP1.
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Affiliation(s)
- Yuki Nakamura
- Department of Molecular Genetics, Institute of Life Science, Kurume University, 1-1 Hyakunen-kouen, Kurume 839-0864, Japan
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Mourouzis I, Giagourta I, Galanopoulos G, Mantzouratou P, Kostakou E, Kokkinos AD, Tentolouris N, Pantos C. Thyroid hormone improves the mechanical performance of the post-infarcted diabetic myocardium: a response associated with up-regulation of Akt/mTOR and AMPK activation. Metabolism 2013; 62:1387-93. [PMID: 23773982 DOI: 10.1016/j.metabol.2013.05.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 05/09/2013] [Accepted: 05/11/2013] [Indexed: 01/18/2023]
Abstract
OBJECTIVE Thyroid hormone (TH) is shown to be protective against cardiac and pancreatic injury. Thus, this study explored the potential effects of TH treatment on the functional status of the postinfarcted diabetic myocardium. Diabetic patients have worse prognosis after acute myocardial infarction (AMI). MATERIALS/METHODS AMI was induced by left coronary ligation in rats previously treated with 35 mg/kg streptozotocin (STZ), (DM-AMI). TH treatment was initiated at 2 weeks after AMI and continued for 6 weeks (DM-AMI+TH), while sham-operated animals served as control (DM-SHAM). RESULTS TH treatment increased cardiac mass, improved wall stress and favorably changed cardiac geometry. TH significantly increased echocardiographic left ventricular ejection fraction (LVEF%): [54.2 (6.5) for DM-AMI+TH vs 37 (2.0) for DM-AMI, p<0.05]. TH treatment resulted in significantly increased insulin and decreased glucose levels in serum. The ratios of phosphorylated (p)-Akt/total Akt and p-mTOR/total mTOR were increased 2.0 fold and 2.7 fold in DM-AMI+TH vs DM-AMI respectively, p<0.05. Furthermore, the ratio of p-AMPK/total AMPK was found to be increased 1.6 fold in DM-AMI+TH vs DM-AMI, p<0.05. CONCLUSION TH treatment improved the mechanical performance of the post-infarcted myocardium in rats with STZ-induced diabetes, an effect which was associated with Akt/mTOR and AMPK activation.
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Affiliation(s)
- Iordanis Mourouzis
- Department of Pharmacology, University of Athens, 75 Mikras Asias Ave., 11527 Goudi, Athens, Greece
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Poleszak E, Wośko S, Serefko A, Szopa A, Wlaź A, Szewczyk B, Nowak G, Wlaź P. Effects of ifenprodil on the antidepressant-like activity of NMDA ligands in the forced swim test in mice. Prog Neuropsychopharmacol Biol Psychiatry 2013; 46:29-35. [PMID: 23774195 DOI: 10.1016/j.pnpbp.2013.06.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2013] [Revised: 04/30/2013] [Accepted: 06/04/2013] [Indexed: 12/30/2022]
Abstract
Multiple pre-clinical and clinical studies clearly displayed implication of the NMDA receptors in development of depressive disorders since a variety of NMDA receptor antagonists exhibit an antidepressant-like effect. The main aim of our study was to assess the influence of ifenprodil - an allosteric modulator selectively binding at the NR2B subunit on the performance in the forced swim test in mice of various NMDA receptor ligands interacting with distinct components of the NMDA receptor complex. Ifenprodil at a dose of 10mg/kg enhanced the antidepressant-like effect of CGP 37849 (a competitive NMDA receptor antagonist, 0.312mg/kg), L-701,324 (an antagonist at glycine site, 1mg/kg), MK-801 (a non-competitive antagonist, 0.05mg/kg) and d-cycloserine (a partial agonist of a glycine site, 2.5mg/kg) but it did not shorten the immobility time of animals which concurrently received an inorganic modulator of the NMDA receptor complex, such as Zn(2+) (2.5mg/kg) or Mg(2+) (10mg/kg). On the other hand, the antidepressant-like effect of ifenprodil (20mg/kg) was reversed by N-methyl-d-aspartic acid (an agonist at the glutamate site, 75mg/kg) or d-serine (an agonist at the glycine site, 100nmol/mouse). In conclusion, the antidepressant-like potential of ifenprodil given concomitantly with NMDA ligands was either reinforced (in the case of both partial agonist and antagonists, except for magnesium and zinc) or diminished (in the case of conventional full agonists).
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Affiliation(s)
- Ewa Poleszak
- Department of Applied Pharmacy, Medical University of Lublin, Chodźki 1, PL 20-093 Lublin, Poland.
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Lima-Ojeda JM, Vogt MA, Pfeiffer N, Dormann C, Köhr G, Sprengel R, Gass P, Inta D. Pharmacological blockade of GluN2B-containing NMDA receptors induces antidepressant-like effects lacking psychotomimetic action and neurotoxicity in the perinatal and adult rodent brain. Prog Neuropsychopharmacol Biol Psychiatry 2013; 45:28-33. [PMID: 23643674 DOI: 10.1016/j.pnpbp.2013.04.017] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2012] [Revised: 04/22/2013] [Accepted: 04/23/2013] [Indexed: 12/01/2022]
Abstract
NMDA receptor (NMDAR) antagonists like ketamine and MK-801 possess remarkable antidepressant effects with fast onset. However, they over-stimulate the retrosplenial cortex, evoking psychosis-like effects and neuronal injury, revealed by de novo induction of the heat shock protein 70 (Hsp70). Moreover, early in the development MK-801 triggers widespread cortical apoptosis, inducing extensive caspase-3 expression. Altogether these data raise strong concerns on the clinical applicability of NMDAR antagonist therapies. Therefore, the development of novel therapeutics targeting more specifically NMDAR to avoid psychotomimetic effects is necessary. Here we investigated a GluN2B (NR2B) antagonist in behavioral and neurotoxicity paradigms in rats to assess its potential as possible alternative to unspecific NMDA receptor antagonists. We found that treatment with the GluN2B specific antagonist Ro 25-6981 evoked robust antidepressant-like effects. Moreover, Ro 25-6981 did not cause hyperactivity as displayed after treatment with unspecific NMDAR antagonists, a correlate of psychosis-like effects in rodents. Additionally, Ro 25-6981, unlike MK-801, did not induce caspase-3 and HSP70 expression, markers of neurotoxicity in the perinatal and adult brain, respectively. Moreover, unexpectedly, in the adult retrosplenial cortex Ro 25-6981 pretreatment significantly reduced MK-801-triggered neurotoxicity. Our results suggest that GluN2B antagonists may represent valuable alternatives to unspecific NMDAR antagonists with robust antidepressant efficacy and a more favorable side-effect profile.
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Affiliation(s)
- Juan M Lima-Ojeda
- RG Animal Models in Psychiatry, Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Germany
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Tomasdottir V, Vikingsson A, Freysdottir J, Hardardottir I. Dietary fish oil reduces the acute inflammatory response and enhances resolution of antigen-induced peritonitis. J Nutr Biochem 2013; 24:1758-65. [PMID: 23769761 DOI: 10.1016/j.jnutbio.2013.03.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 03/02/2013] [Accepted: 03/22/2013] [Indexed: 01/21/2023]
Abstract
Dietary n-3 polyunsaturated fatty acids (PUFA) influence the inductive phase of inflammation but less is known about their effects on the resolution phase. This study examined the effects of dietary fish oil on induction and resolution of antigen-induced inflammation in mice. Mice were fed a control diet with or without 2.8% fish oil, immunized twice with methylated BSA (mBSA) and inflammation induced by intraperitoneal injection of mBSA. Prior to and at different time points after mBSA administration, peritoneal cells were analyzed and expression of surface molecules determined by flow cytometry. Concentration of chemokines, cytokines and soluble cytokine receptors was determined by ELISA. Mice fed the fish oil diet had fewer peritoneal neutrophils, shorter resolution interval and lower levels of pro-inflammatory cytokines and chemokines than mice fed the control diet. In mice fed the fish oil diet there was an early peak in peritoneal levels of the immunosuppressive molecules sIL-6R and TGF-β, that was not seen in mice fed the control diet. In the resolution phase, peritoneal macrophages from mice fed the fish oil diet expressed more of the atypical chemokine receptor D6 and peritoneal TGF-β levels were higher than that in mice fed the control diet. Furthermore, in the late-resolution phase there were more peritoneal eosinophils and macrophages in mice fed the fish oil diet than in mice fed the control diet. These results demonstrate a suppressive effect of n-3 PUFA on the inductive phase of inflammation and indicate an enhancing effect of n-3 PUFA on resolution of inflammation.
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Affiliation(s)
- Valgerdur Tomasdottir
- Department of Biochemistry and Molecular Biology, Biomedical Center, University of Iceland, 101 Reykjavik, Iceland; Center of Rheumatology Research and Department of Immunology, Landspitali - The University Hospital of Iceland, Reykjavik, Iceland
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Barthelmes D, Irhimeh MR, Gillies MC, Karimipour M, Zhou M, Zhu L, Shen WY. Diabetes impairs mobilization of mouse bone marrow-derived Lin(-)/VEGF-R2(+) progenitor cells. Blood Cells Mol Dis 2013; 51:163-73. [PMID: 23714230 DOI: 10.1016/j.bcmd.2013.05.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 04/29/2013] [Accepted: 04/30/2013] [Indexed: 12/29/2022]
Abstract
Endothelial progenitor cells circulating in the peripheral blood (PB) contribute to vascular repair. This study aimed to evaluate the potential of a 'cocktail' consisting of erythropoietin, granulocyte colony-stimulating factor and tetrahydrobiopterin to mobilize hematopoietic lineage negative/vascular endothelial growth factor receptor 2 positive (Lin(-)/VEGF-R2(+)) cells from the bone marrow (BM) to PB in non-diabetic and diabetic mice. Diabetes was induced in mice by intraperitoneal injection of streptozotocin. Diabetic mice were studied after 16weeks of hyperglycemia. Half the mice in each group (non-diabetic and diabetic) received daily intraperitoneal injections of the cocktail for 6 consecutive days while the other half received vehicle buffer. Mobilization of Lin(-)/VEGF-R2(+) cells, which were expanded in MCP301 medium, was evaluated after isolating them from BM and PB and their phenotypic and morphological properties were studied. We found that 16weeks of diabetes affected neither the total number of BM mononucleated cells nor the number of Lin(-)/VEGF-R2(+) cells in BM compared with non-diabetic controls. In non-diabetic mice, cocktail treatment resulted in a significant decrease in BM Lin(-)/VEGF-R2(+) cells, paralleled by a significant increase of these cells in PB. Such changes in the number of Lin(-)/VEGF-R2(+) cells in BM and PB after the cocktail treatment were less marked in diabetic mice. In vitro studies of BM Lin(-)/VEGF-R2(+) cells from diabetic and non-diabetic mice did not reveal any differences in either phenotypes or colony forming potential. These findings indicate that diabetes impairs the mobilization of Lin(-)/VEGF-R2(+) cells from BM to PB. Impaired mobilization of BM Lin(-)/VEGF-R2(+) cells soon after the onset of diabetes may contribute to complications such as diabetic retinopathy.
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Affiliation(s)
- D Barthelmes
- Save Sight Institute, Sydney Hospital and Sydney Eye Hospital, The University of Sydney, Sydney, Australia
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Vogel KR, Arning E, Wasek BL, Bottiglieri T, Gibson KM. Characterization of 2-(methylamino)alkanoic acid capacity to restrict blood-brain phenylalanine transport in Pah enu2 mice: preliminary findings. Mol Genet Metab 2013; 110 Suppl:S71-8. [PMID: 23999161 PMCID: PMC4077276 DOI: 10.1016/j.ymgme.2013.08.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Revised: 08/06/2013] [Accepted: 08/06/2013] [Indexed: 11/21/2022]
Abstract
BACKGROUND Our laboratory seeks a pharmacotherapeutic intervention for PKU that utilizes non-physiological amino acids (NPAAs) to block the accumulation of phenylalanine (Phe) in the brain. In previous studies (Vogel et al. 2013), methylation of the amino group of 2-aminoisobutyrate (AIB) provided an enhanced degree of selectivity for Phe restriction into the brain of Pah(enu2) mice in comparison to unmethylated AIB, leading to the hypothesis that 2-(methylamino)alkanoic acid analogs of AIB might represent targeted inhibitors of Phe accretion into the brain. METHODS Pah(enu2) and control mice were intraperitoneally administered (500-750 mg/kg body weight, once daily; standard 19% protein diet) AIB, methyl AIB (MAIB), isovaline, and two MAIB analogs, 2-methyl-2-(methylamino)butanoic (MeVal) and 3-methyl-2-(methylamino)pentanoic (MePent) acids for one week, followed by brain and blood isolation for amino acid analyses using UPLC. RESULTS In the brain, AIB significantly reduced Phe accretion in Pah(enu2) mice, while MeVal significantly improved glutamine and aspartic acids. Four of five test compounds improved brain threonine and arginine levels. AIB, MAIB and IsoVal significantly reduced blood Phe, with no effect of any drug intervention on other sera amino acids. CONCLUSIONS Further evaluation of AIB and the 2-(methylamino)alkanoic acids as inhibitors of brain Phe accumulation in Pah(enu2) mice is warranted, with more detailed evaluations of route of administration, combinatorial intervention, and detailed toxicity studies.
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Affiliation(s)
- Kara R. Vogel
- Section of Clinical Pharmacology, College of Pharmacy, Washington State University, Spokane, WA, USA
| | - Erland Arning
- Institute for Metabolic Disease, Baylor Research Institute and Baylor University Medical Center, Dallas, TX, USA
| | - Brandi L. Wasek
- Institute for Metabolic Disease, Baylor Research Institute and Baylor University Medical Center, Dallas, TX, USA
| | - Teodoro Bottiglieri
- Institute for Metabolic Disease, Baylor Research Institute and Baylor University Medical Center, Dallas, TX, USA
| | - K. Michael Gibson
- Section of Clinical Pharmacology, College of Pharmacy, Washington State University, Spokane, WA, USA
- Corresponding author at: Section of Clinical Pharmacology, College of Pharmacy, Washington State University, SAC 525M, P.O. Box 1495, 412 E. Spokane Falls Blvd, Spokane, WA 99210-1495, USA. Fax: +1 509 358 6673. (K.M. Gibson)
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