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Vargas-Pinilla P, S Oliveira Fam B, Medina Tavares G, Lima T, Landau L, Paré P, de Cássia Aleixo Tostes R, Pissinatti A, Falótico T, Costa-Neto C, Maestri R, Bortolini MC. From molecular variations to behavioral adaptations: Unveiling adaptive epistasis in primate oxytocin system. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2024; 184:e24947. [PMID: 38783700 DOI: 10.1002/ajpa.24947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 04/12/2024] [Accepted: 04/24/2024] [Indexed: 05/25/2024]
Abstract
OBJECTIVE Our primary objective was to investigate the variability of oxytocin (OT) and the GAMEN binding motif within the LNPEP oxytocinase in primates. MATERIALS AND METHODS We sequenced the LNPEP segment encompassing the GAMEN motif in 34 Platyrrhini species, with 21 of them also sequenced for the OT gene. Our dataset was supplemented with primate sequences of LNPEP, OT, and the oxytocin receptor (OTR) sourced from public databases. Evolutionary analysis and coevolution predictions were made followed by the macroevolution analysis of relevant amino acids associated with phenotypic traits, such as mating systems, parental care, and litter size. To account for phylogenetic structure, we utilized two distinct statistical tests. Additionally, we calculated binding energies focusing on the interaction between Callithtrix jacchus VAMEN and Pro8OT. RESULTS We identified two novel motifs (AAMEN and VAMEN), challenging the current knowledge of motif conservation in placental mammals. Coevolution analysis demonstrated a correlation between GAMEN, AAMEN, and VAMEN and their corresponding OTs and OTRs. Callithrix jacchus exhibited a higher binding energy between VAMEN and Pro8OT than orthologous molecules found in humans (GAMEN and Leu8OT). DISCUSSION The coevolution of AAMEN and VAMEN with their corresponding OTs and OTRs suggests a functional relationship that could have contributed to specific reproductive and adaptive behaviors, including paternal care, social monogamy, and twin births, prominent traits in Cebidae species, such as marmosets and tamarins. Our findings underscore the coevolution of taxon-specific amino acids among the three studied molecules, shedding light on the oxytocinergic system as an adaptive epistatic repertoire in primates.
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Affiliation(s)
- Pedro Vargas-Pinilla
- Laboratory of Human and Molecular Evolution, Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Departamento de Farmacologia, Faculdade de Medicina, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Bibiana S Oliveira Fam
- Laboratory of Human and Molecular Evolution, Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Laboratório de Medicina Genômica, Centro de Pesquisa Experimental (CPE), Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Gustavo Medina Tavares
- Laboratory of Human and Molecular Evolution, Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Thaynara Lima
- Laboratory of Human and Molecular Evolution, Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Luane Landau
- Laboratory of Human and Molecular Evolution, Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Department of Biological Sciences, University at Buffalo, Buffalo, New York, USA
| | - Pâmela Paré
- Laboratory of Human and Molecular Evolution, Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | | | | | - Tiago Falótico
- Escola de Artes, Ciências e Humanidades, Universidade de São Paulo, São Paulo, Brazil
| | - Cláudio Costa-Neto
- Departamento de Bioquímica e Imunologia, Faculdade de Medicina, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Renan Maestri
- Laboratório de Ecomorfologia e Macroevolução, Departamento de Ecologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Maria Cátira Bortolini
- Laboratory of Human and Molecular Evolution, Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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Gising J, Honarnejad S, Bras M, Baillie GL, McElroy SP, Jones PS, Morrison A, Beveridge J, Hallberg M, Larhed M. The Discovery of New Inhibitors of Insulin-Regulated Aminopeptidase by a High-Throughput Screening of 400,000 Drug-like Compounds. Int J Mol Sci 2024; 25:4084. [PMID: 38612894 PMCID: PMC11012289 DOI: 10.3390/ijms25074084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 03/25/2024] [Accepted: 04/02/2024] [Indexed: 04/14/2024] Open
Abstract
With the ambition to identify novel chemical starting points that can be further optimized into small drug-like inhibitors of insulin-regulated aminopeptidase (IRAP) and serve as potential future cognitive enhancers in the clinic, we conducted an ultra-high-throughput screening campaign of a chemically diverse compound library of approximately 400,000 drug-like small molecules. Three biochemical and one biophysical assays were developed to enable large-scale screening and hit triaging. The screening funnel, designed to be compatible with high-density microplates, was established with two enzyme inhibition assays employing either fluorescent or absorbance readouts. As IRAP is a zinc-dependent enzyme, the remaining active compounds were further evaluated in the primary assay, albeit with the addition of zinc ions. Rescreening with zinc confirmed the inhibitory activity for most compounds, emphasizing a zinc-independent mechanism of action. Additionally, target engagement was confirmed using a complementary biophysical thermal shift assay where compounds causing positive/negative thermal shifts were considered genuine binders. Triaging based on biochemical activity, target engagement, and drug-likeness resulted in the selection of 50 qualified hits, of which the IC50 of 32 compounds was below 3.5 µM. Despite hydroxamic acid dominance, diverse chemotypes with biochemical activity and target engagement were discovered, including non-hydroxamic acid compounds. The most potent compound (QHL1) was resynthesized with a confirmed inhibitory IC50 of 320 nM. Amongst these compounds, 20 new compound structure classes were identified, providing many new starting points for the development of unique IRAP inhibitors. Detailed characterization and optimization of lead compounds, considering both hydroxamic acids and other diverse structures, are in progress for further exploration.
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Affiliation(s)
- Johan Gising
- The Beijer Laboratory, Science for Life Laboratory, Department of Medicinal Chemistry, Biomedical Centre, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden; (J.B.); (M.L.)
| | - Saman Honarnejad
- Pivot Park Screening Centre, Kloosterstraat 9, 5349 AB Oss, The Netherlands; (S.H.); (M.B.)
| | - Maaike Bras
- Pivot Park Screening Centre, Kloosterstraat 9, 5349 AB Oss, The Netherlands; (S.H.); (M.B.)
| | - Gemma L. Baillie
- BioAscent Discovery Ltd., Bo‘Ness Road, Newhouse, Motherwell ML1 5UH, UK; (G.L.B.); (S.P.M.); (P.S.J.); (A.M.)
| | - Stuart P. McElroy
- BioAscent Discovery Ltd., Bo‘Ness Road, Newhouse, Motherwell ML1 5UH, UK; (G.L.B.); (S.P.M.); (P.S.J.); (A.M.)
| | - Philip S. Jones
- BioAscent Discovery Ltd., Bo‘Ness Road, Newhouse, Motherwell ML1 5UH, UK; (G.L.B.); (S.P.M.); (P.S.J.); (A.M.)
| | - Angus Morrison
- BioAscent Discovery Ltd., Bo‘Ness Road, Newhouse, Motherwell ML1 5UH, UK; (G.L.B.); (S.P.M.); (P.S.J.); (A.M.)
| | - Julia Beveridge
- The Beijer Laboratory, Science for Life Laboratory, Department of Medicinal Chemistry, Biomedical Centre, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden; (J.B.); (M.L.)
| | - Mathias Hallberg
- The Beijer Laboratory, Department of Pharmaceutical Biosciences, Neuropharmacology and Addiction Research, Biomedical Centre, Uppsala University, P.O. Box 591, SE-751 24 Uppsala, Sweden;
| | - Mats Larhed
- The Beijer Laboratory, Science for Life Laboratory, Department of Medicinal Chemistry, Biomedical Centre, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden; (J.B.); (M.L.)
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3
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Telianidis J, Hunter A, Widdop R, Kemp-Harper B, Pham V, McCarthy C, Chai SY. Inhibition of insulin-regulated aminopeptidase confers neuroprotection in a conscious model of ischemic stroke. Sci Rep 2023; 13:19722. [PMID: 37957163 PMCID: PMC10643421 DOI: 10.1038/s41598-023-46072-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Accepted: 10/27/2023] [Indexed: 11/15/2023] Open
Abstract
Stroke is a leading cause of mortality and morbidity with a paucity of effective pharmacological treatments. We have previously identified insulin-regulated aminopeptidase (IRAP) as a potential target for the development of a new class of drugs for the treatment of stroke, as global deletion of this gene in mice significantly protected against ischemic damage. In the current study, we demonstrate that small molecular weight IRAP inhibitors reduce infarct volume and improve neurological outcome in a hypertensive animal model of ischemic stroke. The effects of two structurally distinct IRAP inhibitors (HFI419 or SJM164) were investigated in a model of stroke where the middle cerebral artery was transiently occluded with endothelin-1 in the conscious spontaneously hypertensive rat. IRAP inhibitor was administered into the lateral ventricle at 2 or 6 h after stroke, with subsequent doses delivered at 24, 48 and 70 h post-stroke. Functional outcomes were assessed prior to drug treatment, and on day 1 and 3 post-stroke. Histological analyses and neuroinflammatory cytokine profiling were conducted at 72 and 24 h post-stroke respectively. IRAP inhibitor treatment following stroke significantly reduced infarct volume and improved neurological and motor deficits. These protective effects were maintained even when the therapeutic window was extended to 6 h. Examination of the cellular architecture at 72 h post-stroke demonstrated that IRAP expression was upregulated in CD11b positive cells and activated astrocytes. Furthermore, IRAP inhibitor treatment significantly increased gene expression for interleukin 6 and C-C motif chemokine ligand 2 in the ischemic core. This study provides proof-of-principle that selective inhibition of IRAP activity with two structurally distinct IRAP inhibitors reduces infarct volume and improves functional outcome even when the first dose is administered 6 h post-stroke. This is the first direct evidence that IRAP inhibitors are a class of drug with potential use in the treatment of ischemic stroke.
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Affiliation(s)
- Jonathon Telianidis
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Andrew Hunter
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Robert Widdop
- Department Pharmacology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Barbara Kemp-Harper
- Department Pharmacology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Vi Pham
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Claudia McCarthy
- Department Pharmacology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Siew Yeen Chai
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia.
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Oyesiji Abiodun A, AlDosari DI, Alghamdi A, Aziz Al-Amri A, Ahmad S, Ola MS. Diabetes-induced stimulation of the renin-angiotensin system in the rat brain cortex. Saudi J Biol Sci 2023; 30:103779. [PMID: 37663397 PMCID: PMC10470205 DOI: 10.1016/j.sjbs.2023.103779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/03/2023] [Accepted: 08/10/2023] [Indexed: 09/05/2023] Open
Abstract
Cerebrovascular disease is a threat to people with diabetes and hypertension. Diabetes can damage the brain by stimulating the renin-angiotensin system (RAS), leading to neurological deficits and brain strokes. Diabetes-induced components of the RAS, including angiotensin-converting enzyme (ACE), angiotensin-II (Ang-II), and angiotensin type 1 receptor (AT1R), have been linked to various neurological disorders in the brain. In this study, we investigated how diabetes and high blood pressure affected the regulation of these major RAS components in the frontal cortex of the rat brain. We dissected, homogenized, and processed the brain cortex tissues of control, streptozotocin-induced diabetic, spontaneously hypertensive (SHR), and streptozotocin-induced SHR rats for biochemical and Western blot analyses. We found that systolic blood pressure was elevated in SHR rats, but there was no significant difference between SHR and diabetic-SHR rats. In contrast to SHR rats, the heartbeat of diabetic SHR rats was low. Western blot analysis showed that the frontal cortexes of the brain expressed angiotensinogen, AT1R, and MAS receptor. There were no significant differences in angiotensinogen levels across the rat groups. However, the AT1R level was increased in diabetic and hypertensive rats compared to controls, whereas the MAS receptor was downregulated (p < 0.05). These findings suggest that RAS overactivation caused by diabetes may have negative consequences for the brain's cortex, leading to neurodegeneration and cognitive impairment.
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Affiliation(s)
- Abeeb Oyesiji Abiodun
- Biochemistry Department, College of Science, King Saud University, 11451,
Riyadh, Saudi Arabia
| | - Dalia I AlDosari
- Biochemistry Department, College of Science, King Saud University, 11451,
Riyadh, Saudi Arabia
| | - Amani Alghamdi
- Biochemistry Department, College of Science, King Saud University, 11451,
Riyadh, Saudi Arabia
| | - Abdul Aziz Al-Amri
- Biochemistry Department, College of Science, King Saud University, 11451,
Riyadh, Saudi Arabia
| | - Sarfaraz Ahmad
- Departments of Surgery, Wake Forest University School of Medicine,
Winston-Salem, NC, USA
| | - Mohammad Shamsul Ola
- Biochemistry Department, College of Science, King Saud University, 11451,
Riyadh, Saudi Arabia
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Cosarderelioglu C, Nidadavolu LS, George CJ, Marx-Rattner R, Powell L, Xue QL, Tian J, Oh ES, Ferrucci L, Dincer P, Bennett DA, Walston JD, Abadir PM. Angiotensin receptor blocker use is associated with upregulation of the memory-protective angiotensin type 4 receptor (AT 4R) in the postmortem brains of individuals without cognitive impairment. GeroScience 2023; 45:371-384. [PMID: 35969296 PMCID: PMC9886717 DOI: 10.1007/s11357-022-00639-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 08/04/2022] [Indexed: 02/03/2023] Open
Abstract
The reported primary dementia-protective benefits of angiotensin II type 1 receptor (AT1R) blockers (ARB) are believed, at least in part, to arise from systemic effects on blood pressure. However, there is a specific and independently regulated brain renin-angiotensin system (RAS). Brain RAS acts mainly through three receptor subtypes; AT1R, AT2R, and AT4R. The AT1R promotes inflammation and mitochondrial reactive oxygen species generation. AT2R increases nitric oxide. AT4R is essential for dopamine and acetylcholine release. It is unknown whether ARB use is associated with changes in the brain RAS. Here, we compared the impact of treatment with ARB on not cognitively impaired individuals and individuals with Alzheimer's dementia using postmortem frontal-cortex samples of age- and sex-matched participants (70-90 years old, n = 30 in each group). We show that ARB use is associated with higher brain AT4R, lower oxidative stress, and amyloid-β burden in NCI participants. In AD, ARB use was associated with lower brain AT1R but had no impact on inflammation, oxidative stress, or amyloid-β burden. Our results may suggest a potential role for AT4R in the salutary effects for ARB on the brains of not cognitively impaired older adults.
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Affiliation(s)
- Caglar Cosarderelioglu
- Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, MD, 21224, USA
- Department of Internal Medicine, Division of Geriatrics, Ankara University School of Medicine, Ankara, Turkey
- Department of Medical Biology, Hacettepe University School of Medicine, Ankara, Turkey
| | - Lolita S Nidadavolu
- Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, MD, 21224, USA
| | - Claudene J George
- Department of Medicine, Division of Geriatrics, Albert Einstein College of Medicine/Montefiore Medical Center, Bronx, NY, USA
| | - Ruth Marx-Rattner
- Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, MD, 21224, USA
| | - Laura Powell
- Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, MD, 21224, USA
| | - Qian-Li Xue
- Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, MD, 21224, USA
- Johns Hopkins University Center On Aging and Health, Baltimore, MD, USA
| | - Jing Tian
- Department of Biostatistics, Bloomberg School of Public Health, Baltimore, MD, USA
| | - Esther S Oh
- Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, MD, 21224, USA
| | - Luigi Ferrucci
- National Institute On Aging, National Institutes of Health, Baltimore, MD, USA
| | - Pervin Dincer
- Department of Medical Biology, Hacettepe University School of Medicine, Ankara, Turkey
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Jeremy D Walston
- Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, MD, 21224, USA
| | - Peter M Abadir
- Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, MD, 21224, USA.
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Akt-mediated mitochondrial metabolism regulates proplatelet formation and platelet shedding post vasopressin exposure. JOURNAL OF THROMBOSIS AND HAEMOSTASIS : JTH 2023; 21:344-358. [PMID: 36700501 DOI: 10.1016/j.jtha.2022.11.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/15/2022] [Accepted: 11/15/2022] [Indexed: 01/26/2023]
Abstract
BACKGROUND Platelet shedding from mature megakaryocytes (MKs) in thrombopoiesis is the critical step for elevating circulating platelets fast and efficiently, however, the underlying mechanism is still not well-illustrated, and the therapeutic targets and candidates are even less. OBJECTIVES In order to investigate the mechanisms for platelet shedding after vasopressin treatment and find new therapeutic targets for thrombocytopenia. METHODS Platelet production was evaluated both in vivo and in vitro after arginine vasopressin (AVP) administration. The underlying biological mechanism of AVP-triggered thrombopoiesis were then investigated by a series of molecular and bioinformatics techniques. RESULTS it is observed that proplatelet formation and platelet shedding in the final stages of thrombopoiesis promoted by AVP, an endogenous hormone, can quickly increases peripheral platelets. This rapid elevation is thus able to speed up platelet recovery after radiation as expected. The mechanism analysis reveal that proplatelet formation and platelet release from mature MKs facilitated by AVP is mainly mediated by Akt-regulated mitochondrial metabolism. In particular, phosphorylated Akt regulates mitochondrial metabolism through driving the association of hexokinase-2 with mitochondrial voltage dependent anion channel-1 in AVP-mediated thrombopoiesis. Further studies suggest that this interaction is stabilized by IκBα, the expression of which is controlled by insulin-regulated membrane aminopeptidase. CONCLUSION these data demonstrate that phosphorylated Akt-mediated mitochondrial metabolism regulates platelet shedding from MKs in response to AVP, which will provide new therapeutic targets and further drug discovery clues for thrombocytopenia treatment.
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Hydrogen Peroxide Induced Toxicity Is Reversed by the Macrocyclic IRAP-Inhibitor HA08 in Primary Hippocampal Cell Cultures. Curr Issues Mol Biol 2022; 44:5000-5012. [PMID: 36286055 PMCID: PMC9601255 DOI: 10.3390/cimb44100340] [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: 09/20/2022] [Revised: 10/14/2022] [Accepted: 10/16/2022] [Indexed: 11/16/2022] Open
Abstract
Angiotensin IV (Ang IV), a metabolite of Angiotensin II, is a bioactive hexapeptide that inhibits the insulin-regulated aminopeptidase (IRAP). This transmembrane zinc metallopeptidase with many biological functions has in recent years emerged as a new pharmacological target. IRAP is expressed in a variety of tissues and can be found in high density in the hippocampus and neocortex, brain regions associated with cognition. Ang IV is known to improve memory tasks in experimental animals. One of the most potent IRAP inhibitors known today is the macrocyclic compound HA08 that is significantly more stable than the endogenous Ang IV. HA08 combines structural elements from Ang IV and the physiological substrates oxytocin and vasopressin, and binds to the catalytic site of IRAP. In the present study we evaluate whether HA08 can restore cell viability in rat primary cells submitted to hydrogen peroxide damage. After damaging the cells with hydrogen peroxide and subsequently treating them with HA08, the conceivable restoring effects of the IRAP inhibitor were assessed. The cellular viability was determined by measuring mitochondrial activity and lactate dehydrogenase (LDH) release. The mitochondrial activity was significantly higher in primary hippocampal cells, whereas the amount of LDH was unaffected. We conclude that the cell viability can be restored in this cell type by blocking IRAP with the potent macrocyclic inhibitor HA08, although the mechanism by which HA08 exerts its effects remains unclear.
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Abstract
Growing evidence implicates the renin-angiotensin system (RAS) in multiple facets of neuropathic pain (NP). This narrative review focuses primarily on the major bioactive RAS peptide, Angiotensin II (Ang II), and its receptors, namely type 1 (AT1R) and type 2 (AT2R). Both receptors are involved in the development of NP and represent potential therapeutic targets. We first discuss the potential role of Ang II receptors in modulation of NP in the central nervous system. Ang II receptor expression is widespread in circuits associated with the perception and modulation of pain, but more studies are required to fully characterize receptor distribution, downstream signaling, and therapeutic potential of targeting the central nervous system RAS in NP. We then describe the peripheral neuronal and nonneuronal distribution of the RAS, and its contribution to NP. Other RAS modulators (such as Ang (1-7)) are briefly reviewed as well. AT1R antagonists are analgesic across different pain models, including NP. Several studies show neuronal protection and outgrowth downstream of AT2R activation, which may lead to the use of AT2R agonists in NP. However, blockade of AT2R results in analgesia. Furthermore, expression of the RAS in the immune system and a growing appreciation of neuroimmune crosstalk in NP add another layer of complexity and therapeutic potential of targeting this pathway. A growing number of human studies also hint at the analgesic potential of targeting Ang II signaling. Altogether, Ang II receptor signaling represents a promising, far-reaching, and novel strategy to treat NP.
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Hallberg M, Larhed M. From Angiotensin IV to Small Peptidemimetics Inhibiting Insulin-Regulated Aminopeptidase. Front Pharmacol 2020; 11:590855. [PMID: 33178027 PMCID: PMC7593869 DOI: 10.3389/fphar.2020.590855] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 09/18/2020] [Indexed: 12/26/2022] Open
Abstract
It was reported three decades ago that intracerebroventricular injection of angiotensin IV (Ang IV, Val-Tyr-Ile-His-Pro-Phe) improved memory and learning in the rat. There are several explanations for these positive effects of the hexapeptide and related analogues on cognition available in the literature. In 2001, it was proposed that the insulin-regulated aminopeptidase (IRAP) is a main target for Ang IV and that Ang IV serves as an inhibitor of the enzyme. The focus of this review is the efforts to stepwise transform the hexapeptide into more drug-like Ang IV peptidemimetics serving as IRAP inhibitors. Moreover, the discovery of IRAP inhibitors by virtual and substance library screening and direct design applying knowledge of the structure of IRAP and of related enzymes is briefly presented.
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Affiliation(s)
- Mathias Hallberg
- The Beijer Laboratory, Division of Biological Research on Drug Dependence, Department of Pharmaceutical Biosciences, BMC, Uppsala University, Uppsala, Sweden
| | - Mats Larhed
- Department of Medicinal Chemistry, Science for Life Laboratory, BMC, Uppsala University, Uppsala, Sweden
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Barlow N, Thompson PE. IRAP Inhibitors: M1-Aminopeptidase Family Inspiration. Front Pharmacol 2020; 11:585930. [PMID: 33101040 PMCID: PMC7546331 DOI: 10.3389/fphar.2020.585930] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 09/04/2020] [Indexed: 11/24/2022] Open
Abstract
The insulin regulated aminopeptidase (IRAP) has been proposed as an important therapeutic target for indications including Alzheimer’s disease and immune disorders. To date, a number of IRAP inhibitor designs have been investigated but the total number of molecules investigated remains quite small. As a member the M1 aminopeptidase family, IRAP shares numerous structural features with the other M1 aminopeptidases. The study of those enzymes and the development of inhibitors provide key learnings and new approaches and are potential sources of inspiration for future IRAP inhibitors.
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Affiliation(s)
- Nicholas Barlow
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Philip E Thompson
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
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Georgiadis D, Ziotopoulou A, Kaloumenou E, Lelis A, Papasava A. The Discovery of Insulin-Regulated Aminopeptidase (IRAP) Inhibitors: A Literature Review. Front Pharmacol 2020; 11:585838. [PMID: 33071797 PMCID: PMC7538644 DOI: 10.3389/fphar.2020.585838] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 08/24/2020] [Indexed: 12/15/2022] Open
Abstract
Insulin-Regulated Aminopeptidase (IRAP, EC 3.4.11.3) is a multi-tasking member of the M1 family of zinc aminopeptidases. Among its diverse biological functions, IRAP is a regulator of oxytocin levels during late stages of pregnancy, it affects cellular glucose uptake by trafficking of the glucose transporter type 4 and it mediates antigen cross-presentation by dendritic cells. Accumulating evidence show that pharmacological inhibition of IRAP may hold promise as a valid approach for the treatment of several pathological states such as memory disorders, neurodegenerative diseases, etc. Aiming to the investigation of physiological roles of IRAP and therapeutic potential of its regulation, intense research efforts have been dedicated to the discovery of small-molecule inhibitors. Moreover, reliable structure-activity relationships have been largely facilitated by recent crystal structures of IRAP and detailed computational studies. This review aims to summarize efforts of medicinal chemists toward the design and development of IRAP inhibitors, with special emphasis to factors affecting inhibitor selectivity.
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Affiliation(s)
- Dimitris Georgiadis
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Athens, Greece
| | - Angeliki Ziotopoulou
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Athens, Greece
| | - Eleni Kaloumenou
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Athens, Greece
| | - Angelos Lelis
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Athens, Greece
| | - Antonia Papasava
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Athens, Greece
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Mpakali A, Saridakis E, Giastas P, Maben Z, Stern LJ, Larhed M, Hallberg M, Stratikos E. Structural Basis of Inhibition of Insulin-Regulated Aminopeptidase by a Macrocyclic Peptidic Inhibitor. ACS Med Chem Lett 2020; 11:1429-1434. [PMID: 32676150 PMCID: PMC7357224 DOI: 10.1021/acsmedchemlett.0c00172] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 06/02/2020] [Indexed: 12/15/2022] Open
Abstract
Insulin-regulated aminopeptidase (IRAP) is a transmembrane zinc metallopeptidase with many important biological functions and an emerging pharmacological target. Although previous structural studies have given insight on how IRAP recognizes linear peptides, how it recognizes its physiological cyclic ligands remains elusive. Here, we report the first crystal structure of IRAP with the macrocyclic peptide inhibitor HA08 that combines structural elements from angiotensin IV and the physiological substrates oxytocin and vasopressin. The compound is found in the catalytic site in a near canonical substrate-like configuration and inhibits by a competitive mechanism. Comparison with previously solved structures of IRAP along with small-angle X-ray scattering experiments suggests that IRAP is in an open conformation in solution but undergoes a closing conformational change upon inhibitor binding. Stabilization of the closed conformation in combination with catalytic water exclusion by the tightly juxtaposed GAMEN loop is proposed as a mechanism of inhibition.
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Affiliation(s)
- Anastasia Mpakali
- National
Center for Scientific Research Demokritos, Agia Paraskevi, Athens 15341, Greece
| | - Emmanuel Saridakis
- National
Center for Scientific Research Demokritos, Agia Paraskevi, Athens 15341, Greece
| | - Petros Giastas
- National
Center for Scientific Research Demokritos, Agia Paraskevi, Athens 15341, Greece
| | - Zachary Maben
- Department
of Pathology, University of Massachusetts
Medical School, Worcester, Massachusetts 01655, United States
| | - Lawrence J. Stern
- Department
of Pathology, University of Massachusetts
Medical School, Worcester, Massachusetts 01655, United States
| | - Mats Larhed
- Department
of Medicinal Chemistry, Science for Life Laboratory, BMC, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden
| | - Mathias Hallberg
- The
Beijer Laboratory, Division of Biological Research on Drug Dependence,
Department of Pharmaceutical Biosciences, BMC, Uppsala University, P.O. Box 591, SE-751 24 Uppsala, Sweden
| | - Efstratios Stratikos
- National
Center for Scientific Research Demokritos, Agia Paraskevi, Athens 15341, Greece
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13
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Ali A, Alzeyoudi SAR, Almutawa SA, Alnajjar AN, Vijayan R. Molecular basis of the therapeutic properties of hemorphins. Pharmacol Res 2020; 158:104855. [PMID: 32438036 DOI: 10.1016/j.phrs.2020.104855] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 04/09/2020] [Accepted: 04/20/2020] [Indexed: 12/26/2022]
Abstract
Hemorphins are endogenous peptides, 4-10 amino acids long, belonging to the family of atypical opioid peptides released during the sequential cleavage of hemoglobin protein. Hemorphins have been shown to exhibit diverse therapeutic effects in both human and animal models. However, the precise cellular and molecular mechanisms involved in such effects remain elusive. In this review, we summarize and propose potential mechanisms based on studies that investigated the biological activity of hemorphins of different lengths on multiple therapeutic targets. Special emphasis is given to molecular events related to renin-angiotensin system (RAS), opioid receptors and insulin-regulated aminopeptidase receptor (IRAP). This review provides a comprehensive coverage of the molecular mechanisms that underpin the therapeutic potential of hemorphins. Furthermore, it highlights the role of various hemorphin residues in pathological conditions, which could be explored further for therapeutic purposes.
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Affiliation(s)
- Amanat Ali
- Department of Biology, College of Science, United Arab Emirates University, PO Box 15551, Al Ain, United Arab Emirates
| | | | - Shamma Abdulla Almutawa
- Department of Biology, College of Science, United Arab Emirates University, PO Box 15551, Al Ain, United Arab Emirates
| | - Alya Nasir Alnajjar
- Department of Biology, College of Science, United Arab Emirates University, PO Box 15551, Al Ain, United Arab Emirates
| | - Ranjit Vijayan
- Department of Biology, College of Science, United Arab Emirates University, PO Box 15551, Al Ain, United Arab Emirates.
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14
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Role of brain renin angiotensin system in neurodegeneration: An update. Saudi J Biol Sci 2020; 27:905-912. [PMID: 32127770 PMCID: PMC7042626 DOI: 10.1016/j.sjbs.2020.01.026] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 01/20/2020] [Accepted: 01/22/2020] [Indexed: 01/12/2023] Open
Abstract
Renin angiotensin system (RAS) is an endocrine system widely known for its physiological roles in electrolyte homeostasis, body fluid volume regulation and cardiovascular control in peripheral circulation. However, brain RAS is an independent form of RAS expressed locally in the brain, which is known to be involved in brain functions and disorders. There is strong evidence for a major involvement of excessive brain angiotensin converting enzyme (ACE)/Angiotensin II (Ang II)/Angiotensin type-1 receptor (AT-1R) axis in increased activation of oxidative stress, apoptosis and neuroinflammation causing neurodegeneration in several brain disorders. Numerous studies have demonstrated strong neuroprotective effects by blocking AT1R in these brain disorders. Additionally, the angiotensin converting enzyme 2 (ACE2)/Angiotensin (1–7)/Mas receptor (MASR), is another axis of brain RAS which counteracts the damaging effects of ACE/Ang II/AT1R axis on neurons in the brain. Thus, angiotensin II receptor blockers (ARBs) and activation of ACE2/Angiotensin (1–7)/MASR axis may serve as an exciting and novel method for neuroprotection in several neurodegenerative diseases. Here in this review article, we discuss the expression of RAS in the brain and highlight how altered RAS level may cause neurodegeneration. Understanding the pathophysiology of RAS and their links to neurodegeneration has enormous potential to identify potentially effective pharmacological tools to treat neurodegenerative diseases in the brain.
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15
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Vasopressin inactivation: Role of insulin-regulated aminopeptidase. VITAMINS AND HORMONES 2019; 113:101-128. [PMID: 32138946 DOI: 10.1016/bs.vh.2019.08.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The physiological importance of vasopressin inactivation has long been appreciated, but the mechanisms and potential pathophysiologic roles of this process remain active subjects of research. Human Placental Leucine Aminopeptidase (P-LAP, encoded by the LNPEP gene) is an important determinant of vasopressinase activity during pregnancy and is associated with gestational diabetes insipidus and preeclampsia. Insulin-Regulated Aminopeptidase (IRAP), the rodent homologue of P-LAP, is coregulated with the insulin-responsive glucose transporter, GLUT4, in adipose and muscle cells. Recently, the Tether containing a UBX domain for GLUT4 (TUG) protein was shown to mediate the coordinated regulation of water and glucose homeostasis. TUG sequesters IRAP and GLUT4 intracellularly in the absence of insulin. Insulin and other stimuli cause the proteolytic cleavage of TUG to mobilize these proteins to the cell surface, where IRAP acts to terminate the activity of circulating vasopressin. Intriguingly, genetic variation in LNPEP is associated with the vasopressin response and mortality during sepsis, and increased copeptin, a marker of vasopressin secretion, is associated with cardiovascular and metabolic disease. We propose that in the setting of insulin resistance in muscle, increased cell-surface IRAP and accelerated vasopressin degradation cause a compensatory increase in vasopressin secretion. The increased vasopressin concentrations present at the kidneys then contribute to hypertension in the metabolic syndrome. Further analyses of metabolism and of vasopressin and copeptin may yield novel insights into a unified pathophysiologic mechanism linking insulin resistance and hypertension, and potentially other components of the metabolic syndrome, in humans.
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16
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Targeting the Oxytocin System: New Pharmacotherapeutic Approaches. Trends Pharmacol Sci 2019; 40:22-37. [DOI: 10.1016/j.tips.2018.11.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 09/27/2018] [Accepted: 11/01/2018] [Indexed: 12/27/2022]
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17
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Jurek B, Neumann ID. The Oxytocin Receptor: From Intracellular Signaling to Behavior. Physiol Rev 2018; 98:1805-1908. [DOI: 10.1152/physrev.00031.2017] [Citation(s) in RCA: 408] [Impact Index Per Article: 68.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The many facets of the oxytocin (OXT) system of the brain and periphery elicited nearly 25,000 publications since 1930 (see FIGURE 1 , as listed in PubMed), which revealed central roles for OXT and its receptor (OXTR) in reproduction, and social and emotional behaviors in animal and human studies focusing on mental and physical health and disease. In this review, we discuss the mechanisms of OXT expression and release, expression and binding of the OXTR in brain and periphery, OXTR-coupled signaling cascades, and their involvement in behavioral outcomes to assemble a comprehensive picture of the central and peripheral OXT system. Traditionally known for its role in milk let-down and uterine contraction during labor, OXT also has implications in physiological, and also behavioral, aspects of reproduction, such as sexual and maternal behaviors and pair bonding, but also anxiety, trust, sociability, food intake, or even drug abuse. The many facets of OXT are, on a molecular basis, brought about by a single receptor. The OXTR, a 7-transmembrane G protein-coupled receptor capable of binding to either Gαior Gαqproteins, activates a set of signaling cascades, such as the MAPK, PKC, PLC, or CaMK pathways, which converge on transcription factors like CREB or MEF-2. The cellular response to OXT includes regulation of neurite outgrowth, cellular viability, and increased survival. OXTergic projections in the brain represent anxiety and stress-regulating circuits connecting the paraventricular nucleus of the hypothalamus, amygdala, bed nucleus of the stria terminalis, or the medial prefrontal cortex. Which OXT-induced patterns finally alter the behavior of an animal or a human being is still poorly understood, and studying those OXTR-coupled signaling cascades is one initial step toward a better understanding of the molecular background of those behavioral effects.
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Affiliation(s)
- Benjamin Jurek
- Department of Behavioural and Molecular Neurobiology, Institute of Zoology, University of Regensburg, Regensburg, Germany
| | - Inga D. Neumann
- Department of Behavioural and Molecular Neurobiology, Institute of Zoology, University of Regensburg, Regensburg, Germany
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18
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Farag E, Sessler DI, Ebrahim Z, Kurz A, Morgan J, Ahuja S, Maheshwari K, John Doyle D. The renin angiotensin system and the brain: New developments. J Clin Neurosci 2017; 46:1-8. [PMID: 28890045 DOI: 10.1016/j.jocn.2017.08.055] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 08/14/2017] [Indexed: 11/19/2022]
Abstract
The traditional renin-angiotensin system (RAS) is indispensable system in adjusting sodium homeostasis, body fluid volume, and controlling arterial blood pressure. The key elements are renin splitting inactive angiotensinogen to yield angiotensin (Ang-I). Ang-1 is then changed by angiotensin-1 converting enzyme (ACE) into angiotensin II (Ang-II). Using PubMed, Google Scholar, and other means, we searched the peer-reviewed literature from 1990 to 2013 for articles on newly discovered findings related to the RAS, especially focusing on how the system influences the central nervous system (CNS). The classical RAS is now considered to be only part of the picture; the discovery of additional RAS pathways in the brain and elsewhere has yielded a vastly improved understanding of how the RAS influences the CNS. Newly discovered effects of the RAS on brain tissue include neuroprotection, cognition, and cerebral vasodilation. A number of brain biochemical pathways are influenced by the brain RAS. Within various pathways, there are potential opportunities for classical pharmacologic interventions as well as the possibility of controlling gene expression.
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Affiliation(s)
- Ehab Farag
- Department of Outcomes Research, Anaesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA; Department of General Anaesthesiology, Anaesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA. http://www.OR.org/
| | - Daniel I Sessler
- Department of Outcomes Research, Anaesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Zeyd Ebrahim
- Department of General Anaesthesiology, Anaesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Andrea Kurz
- Department of Outcomes Research, Anaesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA; Department of General Anaesthesiology, Anaesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Joseph Morgan
- Department of General Anaesthesiology, Anaesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Sanchit Ahuja
- Department of Outcomes Research, Anaesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA; Department of General Anaesthesiology, Anaesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Kamal Maheshwari
- Department of Outcomes Research, Anaesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA; Department of General Anaesthesiology, Anaesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA
| | - D John Doyle
- Department of General Anaesthesiology, Anaesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA
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19
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Bernstein HG, Müller S, Dobrowolny H, Wolke C, Lendeckel U, Bukowska A, Keilhoff G, Becker A, Trübner K, Steiner J, Bogerts B. Insulin-regulated aminopeptidase immunoreactivity is abundantly present in human hypothalamus and posterior pituitary gland, with reduced expression in paraventricular and suprachiasmatic neurons in chronic schizophrenia. Eur Arch Psychiatry Clin Neurosci 2017; 267:427-443. [PMID: 28035472 DOI: 10.1007/s00406-016-0757-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 12/13/2016] [Indexed: 10/20/2022]
Abstract
The vasopressin- and oxytocin-degrading enzyme insulin-regulated aminopeptidase (IRAP) is expressed in various organs including the brain. However, knowledge about its presence in human hypothalamus is fragmentary. Functionally, for a number of reasons (genetic linkage, hydrolysis of oxytocin and vasopressin, its role as angiotensin IV receptor in learning and memory and others) IRAP might play a role in schizophrenia. We studied the regional and cellular localization of IRAP in normal human brain with special emphasis on the hypothalamus and determined numerical densities of IRAP-expressing cells in the paraventricular, supraoptic and suprachiasmatic nuclei in schizophrenia patients and controls. By using immunohistochemistry and Western blot analysis, IRAP was immunolocalized in postmortem human brains. Cell countings were performed to estimate numbers and numerical densities of IRAP immunoreactive hypothalamic neurons in schizophrenia patients and control cases. Shape, size and regional distribution of IRAP-expressing cells, as well the lack of co-localization with the glia marker glutamine synthetase, show that IRAP is expressed in neurons. IRAP immunoreactive cells were observed in the hippocampal formation, cerebral cortex, thalamus, amygdala and, abundantly, hypothalamus. Double labeling experiments (IRAP and oxytocin/neurophysin 1, IRAP with vasopressin/neurophysin 2) revealed that IRAP is present in oxytocinergic and in vasopressinergic neurons. In schizophrenia patients, the numerical density of IRAP-expressing neurons in the paraventricular and the suprachiasmatic nuclei is significantly reduced, which might be associated with the reduction in neurophysin-containing neurons in these nuclei in schizophrenia. The pathophysiological role of lowered hypothalamic IRAP expression in schizophrenia remains to be established.
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Affiliation(s)
- Hans-Gert Bernstein
- Department of Psychiatry and Psychotherapy, Medical Faculty, University of Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany.
| | - Susan Müller
- Department of Psychiatry and Psychotherapy, Medical Faculty, University of Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany
| | - Hendrik Dobrowolny
- Department of Psychiatry and Psychotherapy, Medical Faculty, University of Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany
| | - Carmen Wolke
- Institute of Medical Biochemistry and Molecular Biology, University Medicine, Ernst-Moritz-Arndt-University, 17475, Greifswald, Germany
| | - Uwe Lendeckel
- Institute of Medical Biochemistry and Molecular Biology, University Medicine, Ernst-Moritz-Arndt-University, 17475, Greifswald, Germany
| | - Alicja Bukowska
- EUTRAF Working Group, Molecular Electrophysiology, University Hospital Magdeburg, 39120, Magdeburg, Germany
| | - Gerburg Keilhoff
- Institute of Biochemistry and Cell Biology, Medical Faculty, University of Magdeburg, 39120, Magdeburg, Germany
| | - Axel Becker
- Institute of Pharmacology and Toxicology, Medical Faculty, University of Magdeburg, 39120, Magdeburg, Germany
| | - Kurt Trübner
- Department for Legal Medicine, University of Duisburg-Essen, 45141, Essen, Germany
| | - Johann Steiner
- Department of Psychiatry and Psychotherapy, Medical Faculty, University of Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany
| | - Bernhard Bogerts
- Department of Psychiatry and Psychotherapy, Medical Faculty, University of Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany
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20
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RamIrez-Expósito MJ, MartInez-Martos JM, Palomeque T, Lorite P. A PCR-RFLP method for detection of the LNPEP encoding human insulin-regulated aminopeptidase (IRAP) rs4869317 polymorphism. Indian J Med Res 2017; 144:120-123. [PMID: 27834335 PMCID: PMC5116884 DOI: 10.4103/0971-5916.193298] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background & objectives: Insulin regulated aminopeptidase (IRAP) has been related to certain pathologies such as breast cancer, Alzheimer's disease and septic shock. IRAP is encoded by the leucyl/cystinyl aminopeptidase (LNPEP) gene. The genetic variation in the LNPEP gene has been analyzed in relation with the mortality and vasopressin clearance in septic shock. The LNPEP rs4869317 SNP (single nucleotide polymorphism) was the most significantly associated SNP with vasopressinase activity, being TT genotype associated with increased mortality. The objective of the present study was to develop a simple method to allow a quick and affordable genotyping for the rs4869317 SNP of LNPEP gene. Methods: Blood DNA samples were obtained from randomly selected healthy volunteers (n=28). A pair of primers was designed to amplify an 834 bp region of the LNPEP gene containing the rs4869317 SNP. The two alleles (T or A) were detected by digestion of the PCR products with the PacI restriction endonuclease. This enzyme only cuts the PCR products when the adenine is present in the SNP. Results: All individuals showed RFPL (restriction fragment length polymorphism) fragments for the expected genotypes (TT, TA or AA). The methodology was validated by sequencing of the amplified DNAs from several ‘T/T’ and ‘A/A’ homozygotes and ‘T/A’ heterozygotes. The results from both methods showed agreement. Interpretation & conclusions: The PCR-RFLP is a simple and reliable method that allows a quick genotyping for the rs4869317 SNP of LNPEP gene. The study of this polymorphism could be useful in future investigations to analyze the role of genetic variants of IRAP in several physiological/pathological conditions.
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Affiliation(s)
- MarIa Jesús RamIrez-Expósito
- Experimental & Clinical Physiopathology Research Group, Department of Health Sciences, University of Jaén, 23071 Jaén, Spain
| | - Jos Manuel MartInez-Martos
- Experimental & Clinical Physiopathology Research Group, Department of Health Sciences, University of Jaén, 23071 Jaén, Spain
| | - Teresa Palomeque
- Unit of Genetics, Department of Experimental Biology, University of Jaén, 23071, Jaén, Spain
| | - Pedro Lorite
- Unit of Genetics, Department of Experimental Biology, University of Jaén, 23071, Jaén, Spain
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21
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Molecular Basis of Oxytocin Receptor Signalling in the Brain: What We Know and What We Need to Know. Curr Top Behav Neurosci 2017; 35:3-29. [PMID: 28812263 DOI: 10.1007/7854_2017_6] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Oxytocin (OT), a hypothalamic neuropeptide involved in regulating the social behaviour of all vertebrates, has been proposed as a treatment for a number of neuropsychiatric disorders characterised by deficits in the social domain. Over the last few decades, advances focused on understanding the social effects of OT and its role in physiological conditions and brain diseases, but much less has been done to clarify the molecular cascade of events involved in mediating such effects and in particular the cellular and molecular pharmacology of OT and its target receptor (OTR) in neuronal and glial cells.The entity and persistence of OT activity in the brain is closely related to the expression and regulation of the OTR expressed on the cell surface, which transmits the signal intracellularly and permits OT to affect cell function. Understanding the various signalling mechanisms mediating OTR-induced cell responses is crucial to determine the different responses in different cells and brain regions, and the success of OT and OT-derived analogues in the treatment of neurodevelopmental and psychiatric diseases depends on how well we can control such responses. In this review, we will consider the most important aspects of OT/OTR signalling by focusing on the molecular events involved in OT binding and coupling, on the main signalling pathways activated by the OTR in neuronal cells and on intracellular and plasma membrane OTR trafficking, all of which contribute to the quantitative and qualitative features of OT responses in the brain.
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22
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Slamkova M, Zorad S, Krskova K. Alternative renin-angiotensin system pathways in adipose tissue and their role in the pathogenesis of obesity. Endocr Regul 2016; 50:229-240. [DOI: 10.1515/enr-2016-0025] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Abstract
Adipose tissue expresses all the renin-angiotensin system (RAS) components that play an important role in the adipogenesis, lipid and glucose metabolism regulation in an auto/paracrine manner. The classical RAS has been found to be over-activated during the adipose tissue enlargement, thus elevated generation of angiotensin II (Ang II) may contribute to the obesity pathogenesis. The contemporary view on the RAS has become more complex with the discovery of alternative pathways, including angiotensin-converting enzyme 2 (ACE2)/angiotensin (Ang)-(1-7)/Mas receptor, (pro)renin receptor, as well as angiotensin IV(Ang IV)/AT4 receptor. Ang-(1-7) via Mas receptor counteracts with most of the deleterious effects of the Ang II-mediated by AT1 receptor implying its beneficial role in the glucose and lipid metabolism, oxidative stress, inflammation, and insulin resistance. Pro(renin) receptor may play a role (at least partial) in the pathogenesis of the obesity by increasing the local production of Ang II in adipose tissue as well as triggering signal transduction independently of Ang II. In this review, modulation of alternative RAS pathways in adipose tissue during obesity is discussed and the involvement of Ang-(1-7), (pro)renin and AT4 receptors in the regulation of adipose tissue homeostasis and insulin resistance is summarized.
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Affiliation(s)
- M Slamkova
- Institute of Experimental Endocrinology, Biomedical Research Centre, Slovak Academy of Sciences, Bratislava, Slovakia
| | - S Zorad
- Institute of Experimental Endocrinology, Biomedical Research Centre, Slovak Academy of Sciences, Bratislava, Slovakia
| | - K Krskova
- Institute of Experimental Endocrinology, Biomedical Research Centre, Slovak Academy of Sciences, Bratislava, Slovakia
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23
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Yeatman HR, Albiston AL, Burns P, Chai SY. Forebrain neurone-specific deletion of insulin-regulated aminopeptidase causes age related deficits in memory. Neurobiol Learn Mem 2016; 136:174-182. [PMID: 27713012 DOI: 10.1016/j.nlm.2016.09.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 09/19/2016] [Accepted: 09/25/2016] [Indexed: 12/27/2022]
Abstract
Central infusion of Insulin-Regulated Aminopeptidase (IRAP) inhibitors improves memory in both normal rodents and in models of memory deficit. However, in contrast, the global IRAP knockout mice (KO) demonstrate age-accelerated spatial memory deficits and no improvements in performance in any memory tasks. Potentially, the observed memory deficit could be due to the absence of IRAP in the developing brain. We therefore generated a postnatal forebrain neuron-specific IRAP knockout mouse line (CamKIIalphaCre; IRAPlox/lox). Unexpectedly, we demonstrated that postnatal deletion of IRAP in the brain results in significant deficits in both spatial reference and object recognition memory at three months of age, although spatial working memory remained intact. These results indicate a significant role for IRAP in postnatal brain development and normal function of the hippocampus in adulthood.
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Affiliation(s)
- Holly R Yeatman
- Florey Neuroscience Institutes and Centre for Neuroscience, University of Melbourne, Parkville, Victoria 3052, Australia
| | - Anthony L Albiston
- College of Health and Biomedicine, VU St Albans, Victoria 3021, Australia
| | - Peta Burns
- Department of Physiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Siew Yeen Chai
- Department of Physiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia.
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24
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Grinevich V, Knobloch-Bollmann HS, Eliava M, Busnelli M, Chini B. Assembling the Puzzle: Pathways of Oxytocin Signaling in the Brain. Biol Psychiatry 2016; 79:155-64. [PMID: 26001309 DOI: 10.1016/j.biopsych.2015.04.013] [Citation(s) in RCA: 194] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 04/01/2015] [Accepted: 04/19/2015] [Indexed: 12/24/2022]
Abstract
Oxytocin (OT) is a neuropeptide, which can be seen to be one of the molecules of the decade due to its profound prosocial effects in nonvertebrate and vertebrate species, including humans. Although OT can be detected in various physiological fluids (blood, saliva, urine, cerebrospinal fluid) and brain tissue, it is unclear whether peripheral and central OT releases match and synergize. Moreover, the pathways of OT delivery to brain regions involved in specific behaviors are far from clear. Here, we discuss the evolutionarily and ontogenetically determined pathways of OT delivery and OT signaling, which orchestrate activity of the mesolimbic social decision-making network. Furthermore, we speculate that both the alteration in OT delivery and OT receptor expression may cause behavioral abnormalities in patients afflicted with psychosocial diseases.
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Affiliation(s)
- Valery Grinevich
- Schaller Research Group on Neuropeptides, German Cancer Research Center DKFZ, Heidelberg, Germany; CellNetworks Cluster of Excellence, University of Heidelberg, Heidelberg, Germany.
| | - H Sophie Knobloch-Bollmann
- Schaller Research Group on Neuropeptides, German Cancer Research Center DKFZ, Heidelberg, Germany; CellNetworks Cluster of Excellence, University of Heidelberg, Heidelberg, Germany
| | - Marina Eliava
- Schaller Research Group on Neuropeptides, German Cancer Research Center DKFZ, Heidelberg, Germany; CellNetworks Cluster of Excellence, University of Heidelberg, Heidelberg, Germany
| | - Marta Busnelli
- National Research Council, Institute of Neuroscience, Milan, Italy
| | - Bice Chini
- National Research Council, Institute of Neuroscience, Milan, Italy
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25
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Trans-Modulation of the Somatostatin Type 2A Receptor Trafficking by Insulin-Regulated Aminopeptidase Decreases Limbic Seizures. J Neurosci 2015; 35:11960-75. [PMID: 26311777 DOI: 10.1523/jneurosci.0476-15.2015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
UNLABELLED Within the hippocampus, the major somatostatin (SRIF) receptor subtype, the sst2A receptor, is localized at postsynaptic sites of the principal neurons where it modulates neuronal activity. Following agonist exposure, this receptor rapidly internalizes and recycles slowly through the trans-Golgi network. In epilepsy, a high and chronic release of somatostatin occurs, which provokes, in both rat and human tissue, a decrease in the density of this inhibitory receptor at the cell surface. The insulin-regulated aminopeptidase (IRAP) is involved in vesicular trafficking and shares common regional distribution with the sst2A receptor. In addition, IRAP ligands display anticonvulsive properties. We therefore sought to assess by in vitro and in vivo experiments in hippocampal rat tissue whether IRAP ligands could regulate the trafficking of the sst2A receptor and, consequently, modulate limbic seizures. Using pharmacological and cell biological approaches, we demonstrate that IRAP ligands accelerate the recycling of the sst2A receptor that has internalized in neurons in vitro or in vivo. Most importantly, because IRAP ligands increase the density of this inhibitory receptor at the plasma membrane, they also potentiate the neuropeptide SRIF inhibitory effects on seizure activity. Our results further demonstrate that IRAP is a therapeutic target for the treatment of limbic seizures and possibly for other neurological conditions in which downregulation of G-protein-coupled receptors occurs. SIGNIFICANCE STATEMENT The somatostatin type 2A receptor (sst2A) is localized on principal hippocampal neurons and displays anticonvulsant properties. Following agonist exposure, however, this receptor rapidly internalizes and recycles slowly. The insulin-regulated aminopeptidase (IRAP) is involved in vesicular trafficking and shares common regional distribution with the sst2A receptor. We therefore assessed by in vitro and in vivo experiments whether IRAP could regulate the trafficking of this receptor. We demonstrate that IRAP ligands accelerate sst2A recycling in hippocampal neurons. Because IRAP ligands increase the density of sst2A receptors at the plasma membrane, they also potentiate the effects of this inhibitory receptor on seizure activity. Our results further demonstrate that IRAP is a therapeutic target for the treatment of limbic seizures.
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Karnik SS, Unal H, Kemp JR, Tirupula KC, Eguchi S, Vanderheyden PML, Thomas WG. International Union of Basic and Clinical Pharmacology. XCIX. Angiotensin Receptors: Interpreters of Pathophysiological Angiotensinergic Stimuli [corrected]. Pharmacol Rev 2015; 67:754-819. [PMID: 26315714 PMCID: PMC4630565 DOI: 10.1124/pr.114.010454] [Citation(s) in RCA: 207] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The renin angiotensin system (RAS) produced hormone peptides regulate many vital body functions. Dysfunctional signaling by receptors for RAS peptides leads to pathologic states. Nearly half of humanity today would likely benefit from modern drugs targeting these receptors. The receptors for RAS peptides consist of three G-protein-coupled receptors—the angiotensin II type 1 receptor (AT1 receptor), the angiotensin II type 2 receptor (AT2 receptor), the MAS receptor—and a type II trans-membrane zinc protein—the candidate angiotensin IV receptor (AngIV binding site). The prorenin receptor is a relatively new contender for consideration, but is not included here because the role of prorenin receptor as an independent endocrine mediator is presently unclear. The full spectrum of biologic characteristics of these receptors is still evolving, but there is evidence establishing unique roles of each receptor in cardiovascular, hemodynamic, neurologic, renal, and endothelial functions, as well as in cell proliferation, survival, matrix-cell interaction, and inflammation. Therapeutic agents targeted to these receptors are either in active use in clinical intervention of major common diseases or under evaluation for repurposing in many other disorders. Broad-spectrum influence these receptors produce in complex pathophysiological context in our body highlights their role as precise interpreters of distinctive angiotensinergic peptide cues. This review article summarizes findings published in the last 15 years on the structure, pharmacology, signaling, physiology, and disease states related to angiotensin receptors. We also discuss the challenges the pharmacologist presently faces in formally accepting newer members as established angiotensin receptors and emphasize necessary future developments.
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Affiliation(s)
- Sadashiva S Karnik
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Hamiyet Unal
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Jacqueline R Kemp
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Kalyan C Tirupula
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Satoru Eguchi
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Patrick M L Vanderheyden
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
| | - Walter G Thomas
- Department of Molecular Cardiology, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio (S.S.K., H.U., J.R.K., K.C.T.); Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania (S.E.); Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium (P.M.L.V.); and Department of General Physiology, School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia (W.G.T.)
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Prieto I, Villarejo AB, Segarra AB, Wangensteen R, Banegas I, de Gasparo M, Vanderheyden P, Zorad S, Vives F, Ramírez-Sánchez M. Tissue distribution of CysAP activity and its relationship to blood pressure and water balance. Life Sci 2015; 134:73-8. [DOI: 10.1016/j.lfs.2015.04.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 04/02/2015] [Accepted: 04/18/2015] [Indexed: 12/31/2022]
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Wright JW, Kawas LH, Harding JW. The development of small molecule angiotensin IV analogs to treat Alzheimer's and Parkinson's diseases. Prog Neurobiol 2014; 125:26-46. [PMID: 25455861 DOI: 10.1016/j.pneurobio.2014.11.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 11/17/2014] [Accepted: 11/19/2014] [Indexed: 02/07/2023]
Abstract
Alzheimer's (AD) and Parkinson's (PD) diseases are neurodegenerative diseases presently without effective drug treatments. AD is characterized by general cognitive impairment, difficulties with memory consolidation and retrieval, and with advanced stages episodes of agitation and anger. AD is increasing in frequency as life expectancy increases. Present FDA approved medications do little to slow disease progression and none address the underlying progressive loss of synaptic connections and neurons. New drug design approaches are needed beyond cholinesterase inhibitors and N-methyl-d-aspartate receptor antagonists. Patients with PD experience the symptomatic triad of bradykinesis, tremor-at-rest, and rigidity with the possibility of additional non-motor symptoms including sleep disturbances, depression, dementia, and autonomic nervous system failure. This review summarizes available information regarding the role of the brain renin-angiotensin system (RAS) in learning and memory and motor functions, with particular emphasis on research results suggesting a link between angiotensin IV (AngIV) interacting with the AT4 receptor subtype. Currently there is controversy over the identity of this AT4 receptor protein. Albiston and colleagues have offered convincing evidence that it is the insulin-regulated aminopeptidase (IRAP). Recently members of our laboratory have presented evidence that the brain AngIV/AT4 receptor system coincides with the brain hepatocyte growth factor/c-Met receptor system. In an effort to resolve this issue we have synthesized a number of small molecule AngIV-based compounds that are metabolically stable, penetrate the blood-brain barrier, and facilitate compromised memory and motor systems. These research efforts are described along with details concerning a recently synthesized molecule, Dihexa that shows promise in overcoming memory and motor dysfunctions by augmenting synaptic connectivity via the formation of new functional synapses.
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Affiliation(s)
- John W Wright
- Departments of Psychology, Integrative Physiology and Neuroscience and Program in Biotechnology, Washington State University, Pullman, WA 99164-4820, USA; M3 Biotechnology, Inc., 4000 Mason Rd Suite 300, Box 352141, Seattle, WA 98195-2141, USA.
| | - Leen H Kawas
- Departments of Psychology, Integrative Physiology and Neuroscience and Program in Biotechnology, Washington State University, Pullman, WA 99164-4820, USA; M3 Biotechnology, Inc., 4000 Mason Rd Suite 300, Box 352141, Seattle, WA 98195-2141, USA
| | - Joseph W Harding
- Departments of Psychology, Integrative Physiology and Neuroscience and Program in Biotechnology, Washington State University, Pullman, WA 99164-4820, USA; M3 Biotechnology, Inc., 4000 Mason Rd Suite 300, Box 352141, Seattle, WA 98195-2141, USA
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Tobin VA, Arechaga G, Brunton PJ, Russell JA, Leng G, Ludwig M, Douglas AJ. Oxytocinase in the female rat hypothalamus: a novel mechanism controlling oxytocin neurones during lactation. J Neuroendocrinol 2014; 26:205-16. [PMID: 24612105 DOI: 10.1111/jne.12141] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 02/11/2014] [Accepted: 02/22/2014] [Indexed: 01/09/2023]
Abstract
In addition to its peripheral actions, oxytocin released within the brain is important for birth and essential for milk ejection. The oxytocinase enzyme (placental leucine aminopeptidase; P-LAP) is expressed both peripherally and centrally. P-LAP controls oxytocin degradation in the uterus, placenta and plasma during pregnancy, although its role in the hypothalamus is unclear. We investigated P-LAP expression and activity in the hypothalamus in virgin, pregnant and lactating rats, as well as its role in vivo during the milk-ejection reflex. P-LAP mRNA and protein were expressed in magnocellular neurones of the supraoptic (SON) and paraventricular (PVN) nuclei. Oxytocin neurones co-expressed P-LAP without strong subcellular co-localisation of oxytocin and P-LAP, indicating that they are packaged in separate vesicles. Examination of the intracellular distribution of oxytocin and P-LAP showed a redistribution of P-LAP to within 1 μm of the plasma membrane in the somata of oxytocin neurones during lactation. Both P-LAP mRNA expression and hypothalamic leucyl/cystinyl aminopeptidase activity in the soluble fraction were higher during lactation than in late pregnant or virgin states. Inhibition of central enzyme activity by i.c.v. injection of amastatin in anaesthetised suckling mothers increased the frequency of reflex milk ejections. Because hypothalamic P-LAP expression and activity increase in lactation, and the prevention of its action mimics central oxytocin administration, we conclude that P-LAP regulates auto-excitatory oxytocin actions during the suckling-induced milk-ejection reflex.
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Affiliation(s)
- V A Tobin
- Centre for Integrative Physiology, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, UK
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Cura AJ, Carruthers A. Role of monosaccharide transport proteins in carbohydrate assimilation, distribution, metabolism, and homeostasis. Compr Physiol 2013; 2:863-914. [PMID: 22943001 DOI: 10.1002/cphy.c110024] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The facilitated diffusion of glucose, galactose, fructose, urate, myoinositol, and dehydroascorbicacid in mammals is catalyzed by a family of 14 monosaccharide transport proteins called GLUTs. These transporters may be divided into three classes according to sequence similarity and function/substrate specificity. GLUT1 appears to be highly expressed in glycolytically active cells and has been coopted in vitamin C auxotrophs to maintain the redox state of the blood through transport of dehydroascorbate. Several GLUTs are definitive glucose/galactose transporters, GLUT2 and GLUT5 are physiologically important fructose transporters, GLUT9 appears to be a urate transporter while GLUT13 is a proton/myoinositol cotransporter. The physiologic substrates of some GLUTs remain to be established. The GLUTs are expressed in a tissue specific manner where affinity, specificity, and capacity for substrate transport are paramount for tissue function. Although great strides have been made in characterizing GLUT-catalyzed monosaccharide transport and mapping GLUT membrane topography and determinants of substrate specificity, a unifying model for GLUT structure and function remains elusive. The GLUTs play a major role in carbohydrate homeostasis and the redistribution of sugar-derived carbons among the various organ systems. This is accomplished through a multiplicity of GLUT-dependent glucose sensing and effector mechanisms that regulate monosaccharide ingestion, absorption,distribution, cellular transport and metabolism, and recovery/retention. Glucose transport and metabolism have coevolved in mammals to support cerebral glucose utilization.
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Affiliation(s)
- Anthony J Cura
- Department of Biochemistry & Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
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Nonsocial functions of hypothalamic oxytocin. ISRN NEUROSCIENCE 2013; 2013:179272. [PMID: 24967304 PMCID: PMC4045544 DOI: 10.1155/2013/179272] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Accepted: 04/23/2013] [Indexed: 01/06/2023]
Abstract
Oxytocin (OXT) is a hypothalamic neuropeptide composed of nine amino acids. The functions of OXT cover a variety of social and nonsocial activity/behaviors. Therapeutic effects of OXT on aberrant social behaviors are attracting more attention, such as social memory, attachment, sexual behavior, maternal behavior, aggression, pair bonding, and trust. The nonsocial behaviors/functions of brain OXT have also received renewed attention, which covers brain development, reproduction, sex, endocrine, immune regulation, learning and memory, pain perception, energy balance, and almost all the functions of peripheral organ systems. Coordinating with brain OXT, locally produced OXT also involves the central and peripheral actions of OXT. Disorders in OXT secretion and functions can cause a series of aberrant social behaviors, such as depression, autism, and schizophrenia as well as disturbance of nonsocial behaviors/functions, such as anorexia, obesity, lactation failure, osteoporosis, diabetes, and carcinogenesis. As more and more OXT functions are identified, it is essential to provide a general view of OXT functions in order to explore the therapeutic potentials of OXT. In this review, we will focus on roles of hypothalamic OXT on central and peripheral nonsocial functions.
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Busnelli M, Bulgheroni E, Manning M, Kleinau G, Chini B. Selective and potent agonists and antagonists for investigating the role of mouse oxytocin receptors. J Pharmacol Exp Ther 2013; 346:318-27. [PMID: 23723434 DOI: 10.1124/jpet.113.202994] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The neuropeptides oxytocin (OT) and vasopressin (AVP) have been shown to play a central role in social behaviors; as a consequence, they have been recognized as potential drugs to treat neurodevelopmental and psychiatric disorders characterized by impaired social interactions. However, despite the basic and preclinical relevance of mouse strains carrying genetic alterations in the OT/AVP systems to basic and preclinical translational neuroscience, the pharmacological profile of mouse OT/AVP receptor subtypes has not been fully characterized. To fill in this gap, we have characterized a number of OT and AVP agonists and antagonists at three murine OT/AVP receptors expressed in the nervous system as follows: the oxytocin (mOTR) and vasopressin V1a (mV1aR) and V1b (mV1bR) subtypes. These three receptors were transiently expressed in vitro for binding and intracellular signaling assays, and then a homology model of the mOTR structure was constructed to investigate how its molecular features compare with human and rat OTR orthologs. Our data indicate that the selectivity profile of the natural ligands, OT and AVP, is conserved in humans, rats, and mice. Furthermore, we found that the synthetic peptide [Thr(4)Gly(7)]OT (TGOT) is remarkably selective for the mOTR and, like the endogenous OT ligand, activates Gq and Gi and recruits β-arrestins. Finally, we report three antagonists that exhibit remarkably high affinities and selectivities at mOTRs. These highly selective pharmacological tools will contribute to the investigation of the specific physiologic and pathologic roles of mOTR for the development of selective OT-based therapeutics.
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Chow LH, Tao PL, Chen JC, Liao RM, Chang EP, Huang EYK. A possible correlation between oxytocin-induced and angiotensin IV-induced anti-hyperalgesia at the spinal level in rats. Peptides 2013; 39:21-8. [PMID: 23142109 DOI: 10.1016/j.peptides.2012.10.012] [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: 10/09/2012] [Revised: 10/29/2012] [Accepted: 10/29/2012] [Indexed: 11/29/2022]
Abstract
In our previous study, we showed that intrathecal (i.t.) administration of angiotensin IV (Ang IV), an insulin-regulated aminopeptidase (IRAP) inhibitor, attenuated inflammatory hyperalgesia in rats. Using the plantar test in rats with carrageenan-induced paw inflammation, we investigated the possible mechanism(s) of this effect. Because i.t. oxytocin was reported to produce a dose-dependent anti-hyperalgesia in rats with inflammation, we speculate that there is a possible correlation between oxytocin-induced and Ang IV-induced anti-hyperalgesia. Using i.t. co-administered atosiban (oxytocin receptor antagonist), the anti-hyperalgesia by Ang IV was completely abolished. This indicated that oxytocin could be the major IRAP substrate responsible for the anti-hyperalgesia by Ang IV. When Ang IV was co-administered with a low dose of oxytocin, there was a significant enhancing effect of Ang IV on oxytocin-induced anti-hyperalgesia. In recent reports, electrical stimulation on the paraventricular hypothalamic nucleus (PVN) was proved to increase oxytocin release at the spinal cord. Our results also showed that Ang IV could prolong the anti-hyperalgesia induced by PVN stimulation. This suggests a possible protective effect of Ang IV on endogenous oxytocin degradation/dysfunctioning. Moreover, we examined the local effect of intraplantarly injected Ang IV in the same model. Our results showed no effect of local Ang IV on hyperalgesia and paw edema, indicating that Ang IV may not regulate the peripheral inflammatory process. Overall, our study suggests that Ang IV may act through the inhibition of the activity of IRAP to reduce the degradation of oxytocin at the spinal cord, thereby leading to anti-hyperalgesia in rats with inflammation.
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Affiliation(s)
- Lok-Hi Chow
- Department of Pharmacology, National Defense Medical Center, Taipei, Taiwan
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Abstract
Oxytocin neurons have a physiological role in food intake and energy balance. Central administration of oxytocin is powerfully anorexigenic, reducing food intake and meal duration. The central mechanisms underlying this effect of oxytocin have become better understood in the past few years. Parvocellular neurons of the paraventricular nucleus project to the caudal brainstem to regulate feeding via autonomic functions including the gastrointestinal vago-vagal reflex. In contrast, magnocellular neurons of the supraoptic and paraventricular nuclei release oxytocin from their dendrites to diffuse to distant hypothalamic targets involved in satiety. The ventromedial hypothalamus, for example, expresses a high density of oxytocin receptors but does not contain detectable oxytocin nerve fibers. Magnocellular neurons represent targets for the anorexigenic neuropeptide α-melanocyte stimulating hormone. In addition to homeostatic control, oxytocin may also have a role in reward-related feeding. Evidence suggests that oxytocin can selectively suppress sugar intake and that it may have a role in limiting the intake of palatable food by inhibiting the reward pathway.
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Affiliation(s)
- Nancy Sabatier
- Centre for Integrative Physiology, School of Biomedical Sciences, The University of EdinburghEdinburgh, UK
| | - Gareth Leng
- Centre for Integrative Physiology, School of Biomedical Sciences, The University of EdinburghEdinburgh, UK
| | - John Menzies
- Centre for Integrative Physiology, School of Biomedical Sciences, The University of EdinburghEdinburgh, UK
- *Correspondence: John Menzies, Centre for Integrative Physiology, University of Edinburgh, George Square, Edinburgh, EH8 9XD, UK. e-mail:
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Wright JW, Harding JW. Importance of the brain Angiotensin system in Parkinson's disease. PARKINSON'S DISEASE 2012; 2012:860923. [PMID: 23213621 PMCID: PMC3503402 DOI: 10.1155/2012/860923] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 10/01/2012] [Accepted: 10/02/2012] [Indexed: 11/17/2022]
Abstract
Parkinson's disease (PD) has become a major health problem affecting 1.5% of the world's population over 65 years of age. As life expectancy has increased so has the occurrence of PD. The primary direct consequence of this disease is the loss of dopaminergic (DA) neurons in the substantia nigra and striatum. As the intensity of motor dysfunction increases, the symptomatic triad of bradykinesia, tremors-at-rest, and rigidity occur. Progressive neurodegeneration may also impact non-DA neurotransmitter systems including cholinergic, noradrenergic, and serotonergic, often leading to the development of depression, sleep disturbances, dementia, and autonomic nervous system failure. L-DOPA is the most efficacious oral delivery treatment for controlling motor symptoms; however, this approach is ineffective regarding nonmotor symptoms. New treatment strategies are needed designed to provide neuroprotection and encourage neurogenesis and synaptogenesis to slow or reverse this disease process. The hepatocyte growth factor (HGF)/c-Met receptor system is a member of the growth factor family and has been shown to protect against degeneration of DA neurons in animal models. Recently, small angiotensin-based blood-brain barrier penetrant mimetics have been developed that activate this HGF/c-Met system. These compounds may offer a new and novel approach to the treatment of Parkinson's disease.
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Affiliation(s)
- John W. Wright
- Departments of Psychology, Veterinary and Comparative Anatomy, Pharmacology, and Physiology and Programs in Neuroscience and Biotechnology, Washington State University, P.O. Box 644820, Pullman, WA 99164-4820, USA
| | - Joseph W. Harding
- Departments of Psychology, Veterinary and Comparative Anatomy, Pharmacology, and Physiology and Programs in Neuroscience and Biotechnology, Washington State University, P.O. Box 644820, Pullman, WA 99164-4820, USA
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Cheng BC, Tao PL, Cheng YY, Huang EYK. LVV-hemorphin 7 and angiotensin IV in correlation with antinociception and anti-thermal hyperalgesia in rats. Peptides 2012; 36:9-16. [PMID: 22484286 DOI: 10.1016/j.peptides.2012.03.019] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 03/20/2012] [Accepted: 03/20/2012] [Indexed: 12/01/2022]
Abstract
Hemorphins, a family of atypical endogenous opioid peptides, are produced by the cleavage of hemoglobin β-chain. Hemorphins were proved to bind to the μ-opioid receptors (agonist) and angiotensin IV receptors (insulin-regulated aminopeptidase; IRAP) (inhibitor). Among the hemorphins, LVV-hemorphin-7 (LVV-H7) was found to be abundant and with a longer half life in the CNS. Using intrathecal and intracerebroventricular injections, LVV-H7 and angiotensin IV were given to the rats, which were then subjected to the plantar test and the tail-flick test. Our results showed that LVV-H7 attenuated carrageenan-induced hyperalgesia at the spinal level, which could not be reversed by the co-administration of naloxone. At the supraspinal level, LVV-H7 also produced a significant anti-hyperalgesia effect but with a lower extent. Angiotensin IV showed a similar anti-hyperalgesia effect at the spinal level, but had no effect at the supraspinal level. In the tail-flick test and paw edema test, both peptides showed no effect. These results suggest that LVV-H7 mainly exert the anti-hyperalgesia effect at the spinal level, possibly through IRAP but not μ-opioid receptors. In addition, we observed the expression of IRAP in the CNS of animals with/without carrageenan-induced hyperalgesia. Our results showed a significant expression of IRAP in the spinal cord of rats. However, there was no significant quantitative change of IRAP after the development of hyperalgesia. The serum level of LVV-H7 was also found to be with no change caused by hyperalgesia. These results indicated that the endogenous LVV-H7 and IRAP may not regulate the severity of hyperalgesia through a quantitative change.
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Affiliation(s)
- Bor-Chih Cheng
- Department of Surgery, Chi Mei Medical Center, Tainan, Taiwan, ROC
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Wright JW, Harding JW. The brain renin–angiotensin system: a diversity of functions and implications for CNS diseases. Pflugers Arch 2012; 465:133-51. [DOI: 10.1007/s00424-012-1102-2] [Citation(s) in RCA: 154] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 03/20/2012] [Accepted: 03/30/2012] [Indexed: 12/14/2022]
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Pham V, Albiston AL, Downes CE, Wong CH, Diwakarla S, Ng L, Lee S, Crack PJ, Chai SY. Insulin-Regulated Aminopeptidase Deficiency Provides Protection against Ischemic Stroke in Mice. J Neurotrauma 2012; 29:1243-8. [DOI: 10.1089/neu.2011.1824] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Affiliation(s)
- Vi Pham
- Howard Florey Institute, Victoria, Australia
- Department of Physiology, Monash University, Clayton, Victoria, Australia
| | | | | | - Connie H.Y. Wong
- Department of Pharmacology, University of Melbourne, Victoria, Australia
- Department of Medicine, The University of Calgary, Canada
| | | | - Leelee Ng
- Howard Florey Institute, Victoria, Australia
| | - Seyoung Lee
- Howard Florey Institute, Victoria, Australia
- Department of Pharmacology, Monash University, Clayton, Victoria, Australia
| | - Peter J. Crack
- Department of Pharmacology, University of Melbourne, Victoria, Australia
| | - Siew Yeen Chai
- Howard Florey Institute, Victoria, Australia
- Department of Physiology, Monash University, Clayton, Victoria, Australia
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Saveanu L, van Endert P. The role of insulin-regulated aminopeptidase in MHC class I antigen presentation. Front Immunol 2012; 3:57. [PMID: 22566938 PMCID: PMC3342382 DOI: 10.3389/fimmu.2012.00057] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Accepted: 03/03/2012] [Indexed: 01/08/2023] Open
Abstract
Production of MHC-I ligands from antigenic proteins generally requires multiple proteolytic events. While the proteolytic steps required for antigen processing in the endogenous pathway are clearly established, persisting gaps of knowledge regarding putative cross-presentation compartments have made it difficult to map the precise proteolytic events required for generation of cross-presented antigens. It is only in the past decade that the importance of aminoterminal trimming as the final step in the endogenous presentation pathway has been recognized and that the corresponding enzymes have been described. This review focuses on the aminoterminal trimming of exogenous cross-presented peptides, with particular emphasis on the identification of insulin responsive aminopeptidase (IRAP) as the principal trimming aminopeptidase in endosomes and phagosomes.
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Affiliation(s)
- Loredana Saveanu
- Institut National de la Santé et de le Recherche Médicale Paris, France
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40
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Modi ME, Young LJ. The oxytocin system in drug discovery for autism: animal models and novel therapeutic strategies. Horm Behav 2012; 61:340-50. [PMID: 22206823 PMCID: PMC3483080 DOI: 10.1016/j.yhbeh.2011.12.010] [Citation(s) in RCA: 170] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 12/12/2011] [Accepted: 12/13/2011] [Indexed: 01/13/2023]
Abstract
Animal models and behavioral paradigms are critical for elucidating the neural mechanism involved in complex behaviors, including social cognition. Both genotype and phenotype based models have implicated the neuropeptide oxytocin (OT) in the regulation of social behavior. Based on the findings in animal models, alteration of the OT system has been hypothesized to play a role in the social deficits associated with autism and other neuropsychiatric disorders. While the evidence linking the peptide to the etiology of the disorder is not yet conclusive, evidence from multiple animal models suggest modulation of the OT system may be a viable strategy for the pharmacological treatment of social deficits. In this review, we will discuss how animal models have been utilized to understand the role of OT in social cognition and how those findings can be applied to the conceptualization and treatment of the social impairments in ASD. Animal models with genetic alterations of the OT system, like the OT, OT receptor and CD38 knock-out mice, and those with phenotypic variation in social behavior, like BTBR inbred mice and prairie voles, coupled with behavioral paradigms with face and construct validity may prove to have predictive validity for identifying the most efficacious methods of stimulating the OT system to enhance social cognition in humans. The widespread use of strong animal models of social cognition has the potential yield pharmacological, interventions for the treatment social impairments psychiatric disorders. This article is part of a Special Issue entitled Oxytocin, Vasopressin, and Social Behavior.
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Affiliation(s)
| | - Larry J. Young
- Corresponding author. 954 Gatewood Road, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA. (L.J. Young)
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Albiston AL, Diwakarla S, Fernando RN, Mountford SJ, Yeatman HR, Morgan B, Pham V, Holien JK, Parker MW, Thompson PE, Chai SY. Identification and development of specific inhibitors for insulin-regulated aminopeptidase as a new class of cognitive enhancers. Br J Pharmacol 2012; 164:37-47. [PMID: 21470200 DOI: 10.1111/j.1476-5381.2011.01402.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Two structurally distinct peptides, angiotensin IV and LVV-haemorphin 7, both competitive high-affinity inhibitors of insulin-regulated aminopeptidase (IRAP), were found to enhance aversion-associated and spatial memory in normal rats and to improve performance in a number of memory tasks in rat deficits models. These findings provide compelling support for the development of specific, high-affinity inhibitors of the enzyme as new cognitive enhancing agents. Different classes of IRAP inhibitors have been developed including peptidomimetics and small molecular weight compounds identified through in silico screening with a homology model of the catalytic domain of IRAP. The proof of principal that inhibition of IRAP activity results in facilitation of memory has been obtained by the demonstration that the small-molecule IRAP inhibitors also exhibit memory-enhancing properties.
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Affiliation(s)
- Anthony L Albiston
- Howard Florey Institute, University of Melbourne, Parkville, Victoria, Australia
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42
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Diabetes as a risk factor for Alzheimer's disease: insulin signalling impairment in the brain as an alternative model of Alzheimer's disease. Biochem Soc Trans 2011; 39:891-7. [PMID: 21787319 DOI: 10.1042/bst0390891] [Citation(s) in RCA: 108] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Surprisingly little is known about the mechanisms that trigger the onset of AD (Alzheimer's disease) in sporadic forms. A number of risk factors have been identified that may shed light on the mechanisms that may trigger or facilitate the development of AD. Recently, T2DM (Type 2 diabetes mellitus) has been identified as a risk factor for AD. A common observation for both conditions is the desensitization of insulin receptors in the brain. Insulin acts as a growth factor in the brain and is neuroprotective, activates dendritic sprouting, regeneration and stem cell proliferation. The impairment of this important growth factor signal may facilitate the development of AD. Insulin as well as other growth factors have shown neuroprotective properties in preclinical and clinical trials. Several drugs have been developed to treat T2DM, which re-sensitize insulin receptors and may be of use to prevent neurodegenerative processes in the brain. In particular, the incretins GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insolinotropic polypeptide) are hormones that re-sensitize insulin signalling. Incretins also have similar growth-factor-like properties as insulin and are neuroprotective. In mouse models of AD, GLP-1 receptor agonists reduce amyloid plaque formation, reduce the inflammation response in the brain, protect neurons from oxidative stress, induce neurite outgrowth, and protect synaptic plasticity and memory formation from the detrimental effects caused by β-amyloid production and inflammation. Other growth factors such as BDNF (brain-derived neurotrophic factor), NGF (nerve growth factor) or IGF-1 (insulin-like growth factor 1) also have shown a range of neuroprotective properties in preclinical studies. These results show that these growth factors activate similar cell signalling mechanisms that are protective and regenerative, and suggest that the initial process that may trigger the cascade of neurodegenerative events in AD could be the impairment of growth factor signalling such as early insulin receptor desensitization.
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Wright JW, Harding JW. Brain renin-angiotensin—A new look at an old system. Prog Neurobiol 2011; 95:49-67. [DOI: 10.1016/j.pneurobio.2011.07.001] [Citation(s) in RCA: 147] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 06/27/2011] [Accepted: 07/03/2011] [Indexed: 12/15/2022]
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Andersson H, Demaegdt H, Johnsson A, Vauquelin G, Lindeberg G, Hallberg M, Erdélyi M, Karlén A, Hallberg A. Potent Macrocyclic Inhibitors of Insulin-Regulated Aminopeptidase (IRAP) by Olefin Ring-Closing Metathesis. J Med Chem 2011; 54:3779-92. [DOI: 10.1021/jm200036n] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hanna Andersson
- Department of Medicinal Chemistry, Uppsala University, Box 574, SE-751 23 Uppsala, Sweden
| | - Heidi Demaegdt
- Department of Molecular and Biochemical Pharmacology, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - Anders Johnsson
- Department of Medicinal Chemistry, Uppsala University, Box 574, SE-751 23 Uppsala, Sweden
| | - Georges Vauquelin
- Department of Molecular and Biochemical Pharmacology, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - Gunnar Lindeberg
- Department of Medicinal Chemistry, Uppsala University, Box 574, SE-751 23 Uppsala, Sweden
| | - Mathias Hallberg
- Department of Pharmaceutical Biosciences, Uppsala University, Box 591, SE-751 24 Uppsala, Sweden
| | - Máté Erdélyi
- Department of Chemistry, University of Gothenburg, SE-412 96 Gothenburg, Sweden
- Swedish NMR Centre, University of Gothenburg, Box 465, SE-405 30 Gothenburg, Sweden
| | - Anders Karlén
- Department of Medicinal Chemistry, Uppsala University, Box 574, SE-751 23 Uppsala, Sweden
| | - Anders Hallberg
- Department of Medicinal Chemistry, Uppsala University, Box 574, SE-751 23 Uppsala, Sweden
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Banegas I, Prieto I, Vives F, Alba F, de Gasparo M, Duran R, Segarra AB, Ramírez M. Lateralized response of oxytocinase activity in the medial prefrontal cortex of a unilateral rat model of Parkinson's disease. Behav Brain Res 2010; 213:328-31. [DOI: 10.1016/j.bbr.2010.05.030] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Revised: 05/07/2010] [Accepted: 05/15/2010] [Indexed: 10/19/2022]
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46
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Andersson H, Demaegdt H, Vauquelin G, Lindeberg G, Karlén A, Hallberg M, Erdélyi M, Hallberg A. Disulfide Cyclized Tripeptide Analogues of Angiotensin IV as Potent and Selective Inhibitors of Insulin-Regulated Aminopeptidase (IRAP). J Med Chem 2010; 53:8059-71. [DOI: 10.1021/jm100793t] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Hanna Andersson
- Department of Medicinal Chemistry, Uppsala University, Box 574, SE-751 23 Uppsala, Sweden
| | - Heidi Demaegdt
- Department of Molecular and Biochemical Pharmacology, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - Georges Vauquelin
- Department of Molecular and Biochemical Pharmacology, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - Gunnar Lindeberg
- Department of Medicinal Chemistry, Uppsala University, Box 574, SE-751 23 Uppsala, Sweden
| | - Anders Karlén
- Department of Medicinal Chemistry, Uppsala University, Box 574, SE-751 23 Uppsala, Sweden
| | - Mathias Hallberg
- Department of Pharmaceutical Biosciences, Uppsala University, Box 591, SE-751 24 Uppsala, Sweden
| | - Máté Erdélyi
- Department of Chemistry, University of Gothenburg, SE-412 96 Göteborg, Sweden
| | - Anders Hallberg
- Department of Medicinal Chemistry, Uppsala University, Box 574, SE-751 23 Uppsala, Sweden
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Albiston AL, Yeatman HR, Pham V, Fuller SJ, Diwakarla S, Fernando RN, Chai SY. Distinct distribution of GLUT4 and insulin regulated aminopeptidase in the mouse kidney. ACTA ACUST UNITED AC 2010; 166:83-9. [PMID: 20851149 DOI: 10.1016/j.regpep.2010.09.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Revised: 07/06/2010] [Accepted: 09/13/2010] [Indexed: 11/30/2022]
Abstract
The physiological importance of the insulin responsive glucose transporter GLUT4 in adipocytes and muscle in maintaining glucose homeostasis is well established. A key protein associated with this process is the aminopeptidase IRAP which co-localizes with GLUT4 in specialized vesicles, where it plays a tethering role. In this study, we investigated the distribution of both GLUT4 and IRAP in the kidney to gain insights into the potential roles of these proteins in this organ. Both IRAP and GLUT4 immunostaining was observed in the epithelial cells of the proximal and distal tubules and thick ascending limbs in the cortex, but very little overlap between GLUT4 and IRAP immunoreactivity was observed. GLUT4 staining was consistent with a vesicular localization, whereas IRAP staining was predominantly on the luminal surface. In the principal cells of the inner medulla collecting duct (IMCD), IRAP immunoreactivity was detected throughout the cell, with limited overlap with the vasopressin responsive water channel aquaporin-2 (AQP-2). AQP-2 levels were observed to be two-fold higher in IRAP knockout mice. Based on our results, we propose that GLUT4 plays a role in shunting glucose across epithelial cells. In the kidney cortex, IRAP, in concert with other peptidases, may be important in the generation of free amino acids for uptake, whereas in the principal cells of the inner medulla IRAP may play a localized role in the regulation of vasopressin bioactivity.
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Affiliation(s)
- Anthony L Albiston
- Howard Florey Institute, Florey Neurosciences Institutes, Centre for Neuroscience, University of Melbourne, Parkville, Victoria 3010, Australia.
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Albiston AL, Fernando RN, Yeatman HR, Burns P, Ng L, Daswani D, Diwakarla S, Pham V, Chai SY. Gene knockout of insulin-regulated aminopeptidase: Loss of the specific binding site for angiotensin IV and age-related deficit in spatial memory. Neurobiol Learn Mem 2010; 93:19-30. [DOI: 10.1016/j.nlm.2009.07.011] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2009] [Revised: 07/27/2009] [Accepted: 07/29/2009] [Indexed: 01/14/2023]
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49
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Different cross-presentation pathways in steady-state and inflammatory dendritic cells. Proc Natl Acad Sci U S A 2009; 106:20377-81. [PMID: 19918052 DOI: 10.1073/pnas.0910295106] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Presentation of exogenous antigens on MHC class I molecules, termed cross-presentation, is essential for the induction of CD8 T-cell responses and is carried out by specialized dendritic cell (DC) subsets. The mechanisms involved remain unclear. It has been proposed that antigens could be transported by endocytic receptors, such as the mannose receptor (MR) in the case of soluble ovalbumin, into early endosomes in which the cross-presentation machinery would be recruited. In these endosomal compartments, peptides would be trimmed by the aminopeptidase IRAP before loading onto MHC class I molecules. Here, we have investigated the contribution of this pathway to cross-presentation by steady-state CD8(+) DC and inflammatory monocyte-derived DC (moDC) generated in vivo. We demonstrate that IRAP and MR are dispensable for cross-presentation by CD8(+) DC and for cross-priming. Moreover, we could not find any evidence for diversion of endocytosed antigen into IRAP-containing endosomes in these cells. However, cross-presentation was impaired in moDC deficient in IRAP or MR, confirming the role of these two molecules in inflammatory DC. These results demonstrate that the mechanisms responsible for cross-priming by steady-state and inflammatory DC are different, which has important implications for vaccine design.
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Pham V, Burns P, Albiston AL, Yeatman HR, Ng L, Diwakarla S, Chai SY. Reproduction and maternal behavior in insulin-regulated aminopeptidase (IRAP) knockout mice. Peptides 2009; 30:1861-5. [PMID: 19647771 DOI: 10.1016/j.peptides.2009.07.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Revised: 07/23/2009] [Accepted: 07/23/2009] [Indexed: 10/20/2022]
Abstract
During human pregnancy, a circulating form of insulin-regulated aminopeptidase (IRAP EC 3.4.11.3), often termed oxytocinase or placental leucine aminopeptidase (PLAP), is present in plasma. It is proposed that circulating IRAP plays an important role in regulating the circulating levels of oxytocin and/or vasopressin during pregnancy. We assessed the reproductive and maternal profile of global IRAP knock out mice. No differences in the reproductive profile were observed, with normal gestational period, litter size and parturition recorded. However, western blot analysis of pregnant mouse serum, failed to detect IRAP, a result which was confirmed by fluorimetric IRAP enzyme assay. A review of the literature revealed that the presence of IRAP in the maternal circulation during pregnancy has been only reported in humans. Moreover, the sequence, Phe154 Ala155, identified as the cleavage site for the release of soluble IRAP, is restricted to members of the homindae family. Therefore the absence of IRAP from the circulation in mice, and other species during pregnancy, is due to the inability of a secretase to cleave placental IRAP to produce a soluble form of the enzyme. Given the expression of IRAP in areas of the brain associated with oxytocin modulated maternal behavior, we also investigated whether the IRAP global knockout mice had improved maternal responses. Using standard tests to assess maternal behavior, including pup retrieval, feeding and nurturing, no differences between knock out and wild type dams were observed. In conclusion, the physiological significance of circulating IRAP during human pregnancy cannot be addressed by investigations on mice.
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Affiliation(s)
- Vi Pham
- Florey Neuroscience Institutes, University of Melbourne, Parkville, Melbourne, Victoria 3010, Australia
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