1
|
Tundo GR, Grasso G, Persico M, Tkachuk O, Bellia F, Bocedi A, Marini S, Parravano M, Graziani G, Fattorusso C, Sbardella D. The Insulin-Degrading Enzyme from Structure to Allosteric Modulation: New Perspectives for Drug Design. Biomolecules 2023; 13:1492. [PMID: 37892174 PMCID: PMC10604886 DOI: 10.3390/biom13101492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 09/11/2023] [Accepted: 09/17/2023] [Indexed: 10/29/2023] Open
Abstract
The insulin-degrading enzyme (IDE) is a Zn2+ peptidase originally discovered as the main enzyme involved in the degradation of insulin and other amyloidogenic peptides, such as the β-amyloid (Aβ) peptide. Therefore, a role for the IDE in the cure of diabetes and Alzheimer's disease (AD) has been long envisaged. Anyway, its role in degrading amyloidogenic proteins remains not clearly defined and, more recently, novel non-proteolytic functions of the IDE have been proposed. From a structural point of view, the IDE presents an atypical clamshell structure, underscoring unique enigmatic enzymological properties. A better understanding of the structure-function relationship may contribute to solving some existing paradoxes of IDE biology and, in light of its multifunctional activity, might lead to novel therapeutic approaches.
Collapse
Affiliation(s)
- Grazia Raffaella Tundo
- Department of Clinical Science and Traslational Medicine, University of Rome Tor Vergata, Via Della Ricerca Scientifica 1, 00133 Rome, Italy; (G.R.T.)
| | - Giuseppe Grasso
- Department of Chemical Sciences, University of Catania, Viale Andrea Doria 6, 95125 Catania, Italy;
| | - Marco Persico
- Department of Pharmacy, University of Naples “Federico II”, Via D. Montesano 49, 80131 Napoli, Italy; (M.P.); (O.T.)
| | - Oleh Tkachuk
- Department of Pharmacy, University of Naples “Federico II”, Via D. Montesano 49, 80131 Napoli, Italy; (M.P.); (O.T.)
| | - Francesco Bellia
- Institute of Crystallography, CNR, Via Paolo Gaifami 18, 95126 Catania, Italy
| | - Alessio Bocedi
- Department of Chemical Sciences and Technologies, University of Rome Tor Vergata, Via della Ricerca Scientifica 1, 00133 Rome, Italy
| | - Stefano Marini
- Department of Clinical Science and Traslational Medicine, University of Rome Tor Vergata, Via Della Ricerca Scientifica 1, 00133 Rome, Italy; (G.R.T.)
| | | | - Grazia Graziani
- Department of Systems Medicine, University of Rome Tor Vergata, Via Montpellier 1, 00133 Rome, Italy;
| | - Caterina Fattorusso
- Department of Pharmacy, University of Naples “Federico II”, Via D. Montesano 49, 80131 Napoli, Italy; (M.P.); (O.T.)
| | | |
Collapse
|
2
|
Nishikimi T, Nakagawa Y. B-Type Natriuretic Peptide (BNP) Revisited—Is BNP Still a Biomarker for Heart Failure in the Angiotensin Receptor/Neprilysin Inhibitor Era? BIOLOGY 2022; 11:biology11071034. [PMID: 36101415 PMCID: PMC9312360 DOI: 10.3390/biology11071034] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 06/28/2022] [Accepted: 07/07/2022] [Indexed: 11/16/2022]
Abstract
Simple Summary Active BNP-32, less active proBNP-108, and inactive N-terminal proBNP-76 all circulate in the blood. The circulating protease neprilysin has lower substrate specificity for BNP than ANP, while proBNP and N-terminal proBNP are not degraded by neprilysin. Currently available BNP immunoassays react with both mature BNP and proBNP; therefore, measured plasma BNP is mature BNP + proBNP. Because ARNI administration increases mature BNP, measured plasma BNP initially increases with ARNI administration by the amount of the increase in mature BNP. Later, ARNI administration reduces myocardial wall stress, and the resultant reduction in BNP production more than offsets the increase of mature BNP due to inhibition of degradation by neprilysin, resulting in lower plasma BNP levels. In the ARNI era, BNP remains a useful biomarker for heart failure, though mild increases early during ARNI administration should be taken into consideration. Abstract Myocardial wall stress, cytokines, hormones, and ischemia all stimulate B-type (or brain) natriuretic peptide (BNP) gene expression. Within the myocardium, ProBNP-108, a BNP precursor, undergoes glycosylation, after which a portion is cleaved by furin into mature BNP-32 and N-terminal proBNP-76, depending on the glycosylation status. As a result, active BNP, less active proBNP, and inactive N-terminal proBNP all circulate in the blood. There are three major pathways for BNP clearance: (1) cellular internalization via natriuretic peptide receptor (NPR)-A and NPR-C; (2) degradation by proteases in the blood, including neprilysin, dipeptidyl-peptidase-IV, insulin degrading enzyme, etc.; and (3) excretion in the urine. Because neprilysin has lower substrate specificity for BNP than atrial natriuretic peptide (ANP), the increase in plasma BNP after angiotensin receptor neprilysin inhibitor (ARNI) administration is much smaller than the increase in plasma ANP. Currently available BNP immunoassays react with both mature BNP and proBNP. Therefore, BNP measured with an immunoassay is mature BNP + proBNP. ARNI administration increases mature BNP but not proBNP, as the latter is not degraded by neprilysin. Consequently, measured plasma BNP initially increases with ARNI administration by the amount of the increase in mature BNP. Later, ARNI reduces myocardial wall stress, and the resultant reduction in BNP production more than offsets the increase in mature BNP mediated by inhibiting degradation by neprilysin, which lowers plasma BNP levels. These results suggest that even in the ARNI era, BNP can be used for diagnosis and assessment of the pathophysiology and prognosis of heart failure, though the mild increases early during ARNI administration should be taken into consideration.
Collapse
Affiliation(s)
- Toshio Nishikimi
- Department of Cardiovascular Medicine, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan;
- Department of Medicine, Wakakusa Tatsuma Rehabilitation Hospital, 1580 Ooaza Tatsuma, Daito City 574-0012, Japan
- Correspondence: ; Tel.: +81-75-751-4287
| | - Yasuaki Nakagawa
- Department of Cardiovascular Medicine, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan;
| |
Collapse
|
3
|
Gidlöf O. Toward a New Paradigm for Targeted Natriuretic Peptide Enhancement in Heart Failure. Front Physiol 2021; 12:650124. [PMID: 34721050 PMCID: PMC8548580 DOI: 10.3389/fphys.2021.650124] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 09/21/2021] [Indexed: 12/11/2022] Open
Abstract
The natriuretic peptide system (NPS) plays a fundamental role in maintaining cardiorenal homeostasis, and its potent filling pressure-regulated diuretic and vasodilatory effects constitute a beneficial compensatory mechanism in heart failure (HF). Leveraging the NPS for therapeutic benefit in HF has been the subject of intense investigation during the last three decades and has ultimately reached widespread clinical use in the form of angiotensin receptor-neprilysin inhibition (ARNi). NPS enhancement via ARNi confers beneficial effects on mortality and hospitalization in HF, but inhibition of neprilysin leads to the accumulation of a number of other vasoactive peptides in the circulation, often resulting in hypotension and raising potential concerns over long-term adverse effects. Moreover, ARNi is less effective in the large group of HF patients with preserved ejection fraction. Alternative approaches for therapeutic augmentation of the NPS with increased specificity and efficacy are therefore warranted, and are now becoming feasible particularly with recent development of RNA therapeutics. In this review, the current state-of-the-art in terms of experimental and clinical strategies for NPS augmentation and their implementation will be reviewed and discussed.
Collapse
Affiliation(s)
- Olof Gidlöf
- Department of Cardiology, Clinical Sciences, Lund University, Lund, Sweden
| |
Collapse
|
4
|
Li C, Wang Y, Zhu G, Shang Y, Kang J, Li J. IL-6 induced enhanced clearance of proANP and ANP by insulin-degrading enzyme in T1DM mice. Biochem Cell Biol 2021; 100:37-44. [PMID: 34644519 DOI: 10.1139/bcb-2021-0267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cardiovascular disease (CVD) is a prevalent cause of morbidity and mortality in type I diabetes mellitus (T1DM). However, the pathophysiological mechanisms underlying the relationship between CVD, CVD risk factors, and T1DM have not yet been sufficiently explored. Here, we report that insulin-degrading enzyme (IDE) effectively degrades the precursor of atrial natriuretic peptide (proANP) in HEK293T cells. The pro-inflammatory cytokine IL-6 elicited a significant dose-dependent increase in IDE protein expression. Inhibition of the ERK/MAPK signaling pathway with selumetinib abolished the IL-6-stimulated increase in IDE protein levels and decreased ANP secretion in H9C2 cells. Importantly, the T1DM mouse model displayed lower proANP in the heart and ANP in serum, due to increased IDE expression and activity. Our results suggest a novel role of IL-6 in ANP metabolism via IDE and provide possibilities for new potential therapeutic strategies for diabetes-related cardiovascular complications.
Collapse
Affiliation(s)
- Caiyun Li
- The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China.,The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Yao Wang
- The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China.,The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Guozhen Zhu
- The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China.,The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Yaxian Shang
- The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China.,The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Jiefang Kang
- The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China.,The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Jia Li
- The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China.,The Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| |
Collapse
|
5
|
Modulation of Insulin Sensitivity by Insulin-Degrading Enzyme. Biomedicines 2021; 9:biomedicines9010086. [PMID: 33477364 PMCID: PMC7830943 DOI: 10.3390/biomedicines9010086] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/14/2021] [Accepted: 01/15/2021] [Indexed: 12/15/2022] Open
Abstract
Insulin-degrading enzyme (IDE) is a highly conserved and ubiquitously expressed metalloprotease that degrades insulin and several other intermediate-size peptides. For many decades, IDE had been assumed to be involved primarily in hepatic insulin clearance, a key process that regulates availability of circulating insulin levels for peripheral tissues. Emerging evidence, however, suggests that IDE has several other important physiological functions relevant to glucose and insulin homeostasis, including the regulation of insulin secretion from pancreatic β-cells. Investigation of mice with tissue-specific genetic deletion of Ide in the liver and pancreatic β-cells (L-IDE-KO and B-IDE-KO mice, respectively) has revealed additional roles for IDE in the regulation of hepatic insulin action and sensitivity. In this review, we discuss current knowledge about IDE’s function as a regulator of insulin secretion and hepatic insulin sensitivity, both evaluating the classical view of IDE as an insulin protease and also exploring evidence for several non-proteolytic functions. Insulin proteostasis and insulin sensitivity have both been highlighted as targets controlling blood sugar levels in type 2 diabetes, so a clearer understanding the physiological functions of IDE in pancreas and liver could led to the development of novel therapeutics for the treatment of this disease.
Collapse
|
6
|
Feygina EE, Katrukha AG, Semenov AG. Neutral Endopeptidase (Neprilysin) in Therapy and Diagnostics: Yin and Yang. BIOCHEMISTRY (MOSCOW) 2019; 84:1346-1358. [PMID: 31760922 DOI: 10.1134/s0006297919110105] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Neprilysin (NEP) is a zinc-dependent metalloproteinase that exists in organisms in both transmembrane and soluble forms. NEP substrates are involved in regulating the cardiovascular and nervous systems. In this review, we discuss some of the biochemical characteristics and physiological functions of this enzyme with special emphasis on the use of NEP as a therapeutic target. The history and various physiological aspects of applying NEP inhibitors for treating heart failure and attempts to increase NEP activity when treating Alzheimer's disease using gene and cell therapies are described. Another important issue discussed is the role of NEP as a potential marker for predicting the risk of cardiovascular disease complications. The diagnostic and prognostic performance of soluble NEP in various types of heart failure is analyzed and presented. We also discuss the methods and approaches for measuring NEP activity for prognosis and diagnosis, as well as a possible new role of natriuretic peptides (NEP substrates) in cardiovascular diagnostics.
Collapse
Affiliation(s)
- E E Feygina
- HyTest Ltd., Turku, 20520, Finland. .,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
| | - A G Katrukha
- HyTest Ltd., Turku, 20520, Finland.,Lomonosov Moscow State University, Faculty of Biology, Moscow, 119991, Russia
| | - A G Semenov
- HyTest Ltd., Turku, 20520, Finland.,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
| |
Collapse
|
7
|
Fu S, Chang Z, Luo L, Deng J. Therapeutic Progress and Knowledge Basis on the Natriuretic Peptide System in Heart Failure. Curr Top Med Chem 2019; 19:1850-1866. [PMID: 31448711 DOI: 10.2174/1568026619666190826163536] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 06/25/2019] [Accepted: 07/25/2019] [Indexed: 01/26/2023]
Abstract
Notwithstanding substantial improvements in diagnosis and treatment, Heart Failure (HF) remains a major disease burden with high prevalence and poor outcomes worldwide. Natriuretic Peptides (NPs) modulate whole cardiovascular system and exhibit multiple cardio-protective effects, including the counteraction of the Renin-Angiotensin-Aldosterone System (RAAS) and Sympathetic Nervous System (SNS), promotion of vasodilatation and natriuresis, and inhibition of hypertrophy and fibrosis. Novel pharmacological therapies based on NPs may achieve a valuable shift in managing patients with HF from inhibiting RAAS and SNS to a reversal of neurohormonal imbalance. Enhancing NP bioavailability through exogenous NP administration and inhibiting Neutral Endopeptidase (NEP) denotes valuable therapeutic strategies for HF. On the one hand, NEP-resistant NPs may be more specific as therapeutic choices in patients with HF. On the other hand, NEP Inhibitors (NEPIs) combined with RAAS inhibitors have proved to exert beneficial effects and reduce adverse events in patients with HF. Highly effective and potentially safe Angiotensin Receptor Blocker Neprilysin Inhibitors (ARNIs) have been developed after the failure of NEPIs and Vasopeptidase Inhibitors (VPIs) due to lacking efficacy and safety. Therapeutic progress and knowledge basis on the NP system in HF are summarized in the current review.
Collapse
Affiliation(s)
- Shihui Fu
- Department of Geriatric Cardiology, National Clinical Research Center of Geriatrics Disease, Beijing Key Laboratory of Precision Medicine for Chronic Heart Failure, Chinese People's Liberation Army General Hospital, Beijing, China.,Department of Cardiology, Hainan Hospital of Chinese People's Liberation Army General Hospital, Beijing, China
| | - Zhenyu Chang
- Department of Hepatobiliary and Pancreatic Surgical Oncology, Chinese People's Liberation Army General Hospital, Beijing, China
| | - Leiming Luo
- Department of Geriatric Cardiology, National Clinical Research Center of Geriatrics Disease, Beijing Key Laboratory of Precision Medicine for Chronic Heart Failure, Chinese People's Liberation Army General Hospital, Beijing, China
| | - Juelin Deng
- Department of Cardiology, Hainan Hospital of Chinese People's Liberation Army General Hospital, Beijing, China
| |
Collapse
|
8
|
Najjar SM, Perdomo G. Hepatic Insulin Clearance: Mechanism and Physiology. Physiology (Bethesda) 2019; 34:198-215. [PMID: 30968756 DOI: 10.1152/physiol.00048.2018] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Upon its secretion from pancreatic β-cells, insulin reaches the liver through the portal circulation to exert its action and eventually undergo clearance in the hepatocytes. In addition to insulin secretion, hepatic insulin clearance regulates the homeostatic level of insulin that is required to reach peripheral insulin target tissues to elicit proper insulin action. Receptor-mediated insulin uptake followed by its degradation constitutes the basic mechanism of insulin clearance. Upon its phosphorylation by the insulin receptor tyrosine kinase, carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) takes part in the insulin-insulin receptor complex to increase the rate of its endocytosis and targeting to the degradation pathways. This review summarizes how this process is regulated and how it is associated with insulin-degrading enzyme in the liver. It also discusses the physiological implications of impaired hepatic insulin clearance: Whereas reduced insulin clearance cooperates with increased insulin secretion to compensate for insulin resistance, it can also cause hepatic insulin resistance. Because chronic hyperinsulinemia stimulates hepatic de novo lipogenesis, impaired insulin clearance also causes hepatic steatosis. Thus impaired insulin clearance can underlie the link between hepatic insulin resistance and hepatic steatosis. Delineating these regulatory pathways should lead to building more effective therapeutic strategies against metabolic syndrome.
Collapse
Affiliation(s)
- Sonia M Najjar
- Department of Biomedical Sciences, Ohio University , Athens, Ohio.,Diabetes Institute, Heritage College of Osteopathic Medicine, Ohio University , Athens, Ohio
| | - Germán Perdomo
- Departamento de Ciencias de la Salud, Universidad de Burgos , Burgos , Spain
| |
Collapse
|
9
|
Neutrophil-Initiated Myocardial Inflammation and Its Modulation by B-Type Natriuretic Peptide: A Potential Therapeutic Target. Int J Mol Sci 2018; 20:ijms20010129. [PMID: 30602672 PMCID: PMC6337677 DOI: 10.3390/ijms20010129] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 12/19/2018] [Accepted: 12/22/2018] [Indexed: 12/11/2022] Open
Abstract
Activation of neutrophils is a critically important component of the innate immune response to bacterial and chemical stimuli, and culminates in the “neutrophil burst”, which facilitates neutrophil phagocytosis via the release of superoxide anion radical (O2−) from NADPH oxidase. Excessive and/or prolonged neutrophil activation results in substantial tissue injury and increases in vascular permeability—resulting in sustained tissue infiltration with neutrophils and monocytes, and persistent vasomotor dysfunction. Cardiovascular examples of such changes include acute and chronic systolic and diastolic heart failure (“heart failure with preserved ejection fraction”), and the catecholamine-induced inflammatory disorder takotsubo syndrome. We have recently demonstrated that B-type natriuretic peptide (BNP), acting via inhibition of activation of neutrophil NADPH oxidase, is an important negative modulator of the “neutrophil burst”, though its effectiveness in limiting tissue injury is partially lost in acute heart failure. The potential therapeutic implications of these findings, regarding the development of new means of treating both acute and chronic cardiac injury states, are discussed.
Collapse
|
10
|
Rapley SA, Prickett TCR, Dalrymple-Alford JC, Espiner EA. Environmental Enrichment Elicits a Transient Rise of Bioactive C-Type Natriuretic Peptide in Young but Not Aged Rats. Front Behav Neurosci 2018; 12:142. [PMID: 30072880 PMCID: PMC6060231 DOI: 10.3389/fnbeh.2018.00142] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 06/22/2018] [Indexed: 11/13/2022] Open
Abstract
Beneficial molecular and neuroplastic changes have been demonstrated in response to environmental enrichment (EE) in laboratory animals across the lifespan. Here, we investigated whether these effects extend to C-type Natriuretic Peptide (CNP), a widely expressed neuropeptide with putative involvement in neuroprotection, neuroplasticity, anxiety, and learning and memory. We determined the CNP response in 36 young (8-9 months) and 36 aged (22-23 months) male PVGc hooded rats that were rehoused with new cage mates in either standard laboratory cages or EE for periods of 14 or 28 days. Tissues were rapidly excised from four brain regions associated with memory formation (dorsal hippocampus, retrosplenial cortex, medial prefrontal cortex, and mammillary bodies) plus the occipital cortex and hypothalamus, and immediately frozen. Radioimmunoassay was used to measure bioactive CNP and the amino-terminal fragment of proCNP, NTproCNP. Because CNP but not NTproCNP is rapidly degraded at source, NTproCNP reflects CNP production whereas the ratio NTproCNP:CNP is a biomarker of CNP's local degradation rate. EE increased CNP at 14 days in all brain regions in young, but not old rats; this effect in young rats was lost at 28 days in all regions of interest. NTproCNP:CNP ratio, but not NTproCNP, was reduced in all regions by EE at 14 days in young rats, but not in old rats, which suggests a period of reduced degradation or receptor mediated clearance, rather than increased production of CNP in these young EE rats. Aged rats tended to show reduced NTproCNP:CNP ratios but this did not occur in dorsal hippocampus or mammillary bodies. This is the first study demonstrating modulation of CNP protein concentrations, and the effect of age, in response to environmental stimulation. Furthermore, it is the first to show that changes in degradation rate in vivo may be an important component in determining CNP bioactivity in neural tissues.
Collapse
Affiliation(s)
- Susan A. Rapley
- Brain Research New Zealand and Psychology, University of Canterbury, Christchurch, New Zealand
| | | | | | - Eric A. Espiner
- Department of Medicine, University of Otago, Christchurch, New Zealand
| |
Collapse
|
11
|
Fu S, Ping P, Wang F, Luo L. Synthesis, secretion, function, metabolism and application of natriuretic peptides in heart failure. J Biol Eng 2018; 12:2. [PMID: 29344085 PMCID: PMC5766980 DOI: 10.1186/s13036-017-0093-0] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 12/21/2017] [Indexed: 12/11/2022] Open
Abstract
As a family of hormones with pleiotropic effects, natriuretic peptide (NP) system includes atrial NP (ANP), B-type NP (BNP), C-type NP (CNP), dendroaspis NP and urodilatin, with NP receptor-A (guanylate cyclase-A), NP receptor-B (guanylate cyclase-B) and NP receptor-C (clearance receptor). These peptides are genetically distinct, but structurally and functionally related for regulating circulatory homeostasis in vertebrates. In humans, ANP and BNP are encoded by NP precursor A (NPPA) and NPPB genes on chromosome 1, whereas CNP is encoded by NPPC on chromosome 2. NPs are synthesized and secreted through certain mechanisms by cardiomyocytes, fibroblasts, endotheliocytes, immune cells (neutrophils, T-cells and macrophages) and immature cells (embryonic stem cells, muscle satellite cells and cardiac precursor cells). They are mainly produced by cardiovascular, brain and renal tissues in response to wall stretch and other causes. NPs provide natriuresis, diuresis, vasodilation, antiproliferation, antihypertrophy, antifibrosis and other cardiometabolic protection. NPs represent body's own antihypertensive system, and provide compensatory protection to counterbalance vasoconstrictor-mitogenic-sodium retaining hormones, released by renin-angiotensin-aldosterone system (RAAS) and sympathetic nervous system (SNS). NPs play central roles in regulation of heart failure (HF), and are inactivated through not only NP receptor-C, but also neutral endopeptidase (NEP), dipeptidyl peptidase-4 and insulin degrading enzyme. Both BNP and N-terminal proBNP are useful biomarkers to not only make the diagnosis and assess the severity of HF, but also guide the therapy and predict the prognosis in patients with HF. Current NP-augmenting strategies include the synthesis of NPs or agonists to increase NP bioactivity and inhibition of NEP to reduce NP breakdown. Nesiritide has been established as an available therapy, and angiotensin receptor blocker NEP inhibitor (ARNI, LCZ696) has obtained extremely encouraging results with decreased morbidity and mortality. Novel pharmacological approaches based on NPs may promote a therapeutic shift from suppressing the RAAS and SNS to re-balancing neuroendocrine dysregulation in patients with HF. The current review discussed the synthesis, secretion, function and metabolism of NPs, and their diagnostic, therapeutic and prognostic values in HF.
Collapse
Affiliation(s)
- Shihui Fu
- Department of Geriatric Cardiology, Chinese People’s Liberation Army General Hospital, Beijing, 100853 China
- Department of Cardiology and Hainan Branch, Chinese People’s Liberation Army, General Hospital, Beijing, China
| | - Ping Ping
- Department of Pharmaceutical Care, Chinese People’s, Liberation Army General Hospital, Beijing, China
| | - Fengqi Wang
- Department of Cardiology and Hainan Branch, Chinese People’s Liberation Army, General Hospital, Beijing, China
| | - Leiming Luo
- Department of Geriatric Cardiology, Chinese People’s Liberation Army General Hospital, Beijing, 100853 China
| |
Collapse
|
12
|
Tundo GR, Sbardella D, Ciaccio C, Grasso G, Gioia M, Coletta A, Polticelli F, Di Pierro D, Milardi D, Van Endert P, Marini S, Coletta M. Multiple functions of insulin-degrading enzyme: a metabolic crosslight? Crit Rev Biochem Mol Biol 2017. [PMID: 28635330 DOI: 10.1080/10409238.2017.1337707] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Insulin-degrading enzyme (IDE) is a ubiquitous zinc peptidase of the inverzincin family, which has been initially discovered as the enzyme responsible for insulin catabolism; therefore, its involvement in the onset of diabetes has been largely investigated. However, further studies on IDE unraveled its ability to degrade several other polypeptides, such as β-amyloid, amylin, and glucagon, envisaging the possible implication of IDE dys-regulation in the "aggregopathies" and, in particular, in neurodegenerative diseases. Over the last decade, a novel scenario on IDE biology has emerged, pointing out a multi-functional role of this enzyme in several basic cellular processes. In particular, latest advances indicate that IDE behaves as a heat shock protein and modulates the ubiquitin-proteasome system, suggesting a major implication in proteins turnover and cell homeostasis. In addition, recent observations have highlighted that the regulation of glucose metabolism by IDE is not merely based on its largely proposed role in the degradation of insulin in vivo. There is increasing evidence that improper IDE function, regulation, or trafficking might contribute to the etiology of metabolic diseases. In addition, the enzymatic activity of IDE is affected by metals levels, thus suggesting a role also in the metal homeostasis (metallostasis), which is thought to be tightly linked to the malfunction of the "quality control" machinery of the cell. Focusing on the physiological role of IDE, we will address a comprehensive vision of the very complex scenario in which IDE takes part, outlining its crucial role in interconnecting several relevant cellular processes.
Collapse
Affiliation(s)
- Grazia R Tundo
- a Department of Clinical Sciences and Translation Medicine , University of Roma Tor Vergata , Roma , Italy.,b CIRCMSB , Bari , Italy
| | - Diego Sbardella
- a Department of Clinical Sciences and Translation Medicine , University of Roma Tor Vergata , Roma , Italy.,b CIRCMSB , Bari , Italy.,c Center for TeleInfrastructures, University of Roma Tor Vergata , Roma , Italy
| | - Chiara Ciaccio
- a Department of Clinical Sciences and Translation Medicine , University of Roma Tor Vergata , Roma , Italy.,b CIRCMSB , Bari , Italy
| | - Giuseppe Grasso
- d Department of Chemistry , University of Catania , Catania , Italy.,e CNR IBB , Catania , Italy
| | - Magda Gioia
- a Department of Clinical Sciences and Translation Medicine , University of Roma Tor Vergata , Roma , Italy.,b CIRCMSB , Bari , Italy
| | - Andrea Coletta
- f Department of Chemistry , University of Aarhus , Aarhus , Denmark
| | | | - Donato Di Pierro
- a Department of Clinical Sciences and Translation Medicine , University of Roma Tor Vergata , Roma , Italy.,b CIRCMSB , Bari , Italy
| | | | - Peter Van Endert
- h Université Paris Descartes, INSERM, U1151, CNRS , Paris , France
| | - Stefano Marini
- a Department of Clinical Sciences and Translation Medicine , University of Roma Tor Vergata , Roma , Italy.,b CIRCMSB , Bari , Italy.,c Center for TeleInfrastructures, University of Roma Tor Vergata , Roma , Italy
| | - Massimo Coletta
- a Department of Clinical Sciences and Translation Medicine , University of Roma Tor Vergata , Roma , Italy.,b CIRCMSB , Bari , Italy.,c Center for TeleInfrastructures, University of Roma Tor Vergata , Roma , Italy
| |
Collapse
|
13
|
Ichiki T, Burnett Jr JC. Atrial Natriuretic Peptide ― Old But New Therapeutic in Cardiovascular Diseases ―. Circ J 2017; 81:913-919. [DOI: 10.1253/circj.cj-17-0499] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Tomoko Ichiki
- Cardiorenal Research Laboratory, Department of Cardiovascular Medicine, Mayo Clinic
| | - John C. Burnett Jr
- Cardiorenal Research Laboratory, Department of Cardiovascular Medicine, Mayo Clinic
| |
Collapse
|
14
|
Clerico A, Passino C, Franzini M, Emdin M. Natriuretic peptides as biomarkers of cardiac endocrine function in heart failure: new challenges and perspectives. Future Cardiol 2016; 12:573-84. [DOI: 10.2217/fca-2016-0013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Several studies indicated that B-type natriuretic peptide (BNP) assay is able to detect patients even in the early phases of heart failure (HF), when the myocardial remodeling process may be still reversible. BNP assay may assist the physician to initiate appropriate and prompt pharmacological treatments. However, clinical relevance and result interpretation of BNP assay for the guide of therapy or in particular clinical conditions, such as renal failure or treatment with inhibitors of enzymes degrading BNP in HF patients, are still debated. The aim of this article is to discuss some still controversial issues concerning the clinical use of measurement of cardiac natriuretic peptides, and also to provide a general overview and some perspectives related to pathophysiological mechanisms of HF.
Collapse
Affiliation(s)
- Aldo Clerico
- Scuola Superiore Sant'Anna & Fondazione CNR – Regione Toscana, Pisa, Italy
| | - Claudio Passino
- Scuola Superiore Sant'Anna & Fondazione CNR – Regione Toscana, Pisa, Italy
| | - Maria Franzini
- Dipartimento di Ricerca Traslazionale e delle Nuove Tecnologie in Medicina e Chirurgia, University of Pisa, Pisa, Italy
| | - Michele Emdin
- Scuola Superiore Sant'Anna & Fondazione CNR – Regione Toscana, Pisa, Italy
| |
Collapse
|
15
|
The natriuretic peptides system in the pathophysiology of heart failure: from molecular basis to treatment. Clin Sci (Lond) 2016; 130:57-77. [PMID: 26637405 PMCID: PMC5233571 DOI: 10.1042/cs20150469] [Citation(s) in RCA: 180] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
After its discovery in the early 1980s, the natriuretic peptide (NP) system has been extensively characterized and its potential influence in the development and progression of heart failure (HF) has been investigated. HF is a syndrome characterized by the activation of different neurohormonal systems, predominantly the renin-angiotensin (Ang)-aldosterone system (RAAS) and the sympathetic nervous system (SNS), but also the NP system. Pharmacological interventions have been developed to counteract the neuroendocrine dysregulation, through the down modulation of RAAS with ACE (Ang-converting enzyme) inhibitors, ARBs (Ang receptor blockers) and mineralcorticoid antagonists and of SNS with β-blockers. In the last years, growing attention has been paid to the NP system. In the present review, we have summarized the current knowledge on the NP system, focusing on its role in HF and we provide an overview of the pharmacological attempts to modulate NP in HF: from the negative results of the study with neprilysin (NEP) inhibitors, alone or associated with an ACE inhibitor and vasopeptidase inhibitors, to the most recently and extremely encouraging results obtained with the new pharmacological class of Ang receptor and NEP inhibitor, currently defined ARNI (Ang receptor NEP inhibitor). Indeed, this new class of drugs to manage HF, supported by the recent results and a vast clinical development programme, may prompt a conceptual shift in the treatment of HF, moving from the inhibition of RAAS and SNS to a more integrated target to rebalance neurohormonal dysregulation in HF.
Collapse
|
16
|
Mair J, Lindahl B, Giannitsis E, Huber K, Thygesen K, Plebani M, Möckel M, Müller C, Jaffe AS. Will sacubitril-valsartan diminish the clinical utility of B-type natriuretic peptide testing in acute cardiac care? EUROPEAN HEART JOURNAL-ACUTE CARDIOVASCULAR CARE 2016; 6:321-328. [PMID: 26758541 DOI: 10.1177/2048872615626355] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Since the approval of sacubitril-valsartan for the treatment of chronic heart failure with reduced ejection fraction, a commonly raised suspicion is that a wider clinical use of this new drug may diminish the clinical utility of B-type natriuretic peptide testing as sacubitril may interfere with B-type natriuretic peptide clearance. In this education paper we critically assess this hypothesis based on the pathophysiology of the natriuretic peptide system and the limited published data on the effects of neprilysin inhibition on natriuretic peptide plasma concentrations in humans. As the main clinical application of B-type natriuretic peptide testing in acute cardiac care is and will be the rapid rule-out of suspected acute heart failure there is no significant impairment to be expected for B-type natriuretic peptide testing in the acute setting. However, monitoring of chronic heart failure patients on sacubitril-valsartan treatment with B-type natriuretic peptide testing may be impaired. In contrast to N-terminal-proBNP, the current concept that the lower the B-type natriuretic peptide result in chronic heart failure patients, the better the prognosis during treatment monitoring, may no longer be true.
Collapse
Affiliation(s)
- Johannes Mair
- 1 Department of Internal Medicine III - Cardiology and Angiology, Medical University Innsbruck, Austria
| | - Bertil Lindahl
- 2 Department of Medical Sciences, Uppsala University and Uppsala Clinical Research Center, Sweden
| | | | - Kurt Huber
- 4 Department of Medicine, Cardiology and Intensive Care Medicine, Wilhelminen Hospital, Austria
| | | | - Mario Plebani
- 6 Department of Laboratory Medicine, University Hospital Padova, Italy
| | - Martin Möckel
- 7 Division of Emergency Medicine and Department of Cardiology, Charité- Universitätsmedizin Berlin, Germany
| | - Christian Müller
- 8 Department of Cardiology and Cardiovascular Research Institute Basel, University Hospital Basel, Switzerland
| | | | | |
Collapse
|
17
|
Clerico A, Franzini M, Masotti S, Prontera C, Passino C. State of the art of immunoassay methods for B-type natriuretic peptides: An update. Crit Rev Clin Lab Sci 2014; 52:56-69. [PMID: 25547534 DOI: 10.3109/10408363.2014.987720] [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] [Indexed: 11/13/2022]
Abstract
The aim of this review article is to give an update on the state of the art of the immunoassay methods for the measurement of B-type natriuretic peptide (BNP) and its related peptides. Using chromatographic procedures, several studies reported an increasing number of circulating peptides related to BNP in human plasma of patients with heart failure. These peptides may have reduced or even no biological activity. Furthermore, other studies have suggested that, using immunoassays that are considered specific for BNP, the precursor of the peptide hormone, proBNP, constitutes a major portion of the peptide measured in plasma of patients with heart failure. Because BNP immunoassay methods show large (up to 50%) systematic differences in values, the use of identical decision values for all immunoassay methods, as suggested by the most recent international guidelines, seems unreasonable. Since proBNP significantly cross-reacts with all commercial immunoassay methods considered specific for BNP, manufacturers should test and clearly declare the degree of cross-reactivity of glycosylated and non-glycosylated proBNP in their BNP immunoassay methods. Clinicians should take into account that there are large systematic differences between methods when they compare results from different laboratories that use different BNP immunoassays. On the other hand, clinical laboratories should take part in external quality assessment (EQA) programs to evaluate the bias of their method in comparison to other BNP methods. Finally, the authors believe that the development of more specific methods for the active peptide, BNP1-32, should reduce the systematic differences between methods and result in better harmonization of results.
Collapse
Affiliation(s)
- Aldo Clerico
- Scuola Superiore Sant'Anna and Fondazione G. Monasterio CNR - Regione Toscana , Pisa , Italy
| | | | | | | | | |
Collapse
|
18
|
Huntley BK, Sandberg SM, Heublein DM, Sangaralingham SJ, Burnett JC, Ichiki T. Pro-B-type natriuretic peptide-1-108 processing and degradation in human heart failure. Circ Heart Fail 2014; 8:89-97. [PMID: 25339504 DOI: 10.1161/circheartfailure.114.001174] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
BACKGROUND We have reported that pro-B-type natriuretic peptide (BNP)-1-108 circulates and is processed to mature BNP1-32 in human blood. Building on these findings, we sought to determine whether proBNP1-108 processed forms in normal circulation are biologically active and stimulate cGMP, and whether proBNP1-108 processing and activity are altered in human heart failure (HF) compared with normal. Because BNP1-32 is deficient whereas proBNP1-108 is abundant in HF, we hypothesize that proBNP1-108 processing and degradation are impaired in HF patients ex vivo. METHODS AND RESULTS We measured circulating molecular forms, including BNP1-32, proBNP1-108, and N-terminal-proBNP, and all were significantly higher in patients with HF when compared with that in normals. Fresh serum samples from normals or patients with HF were incubated with or without exogenous nonglycosylated proBNP1-108 tagged with 6 C-terminal Histidines to facilitate peptide isolation. His-tag proBNP1-108 was efficiently processed into BNP1-32/3-32 at 5 minutes in normal serum, persisted for 15 minutes, then disappeared. Delayed processing of proBNP1-108 was observed in HF samples, and the degradation pattern differed depending on left ventricular function. The 5-minute processed forms from both normal and HF serums were active and generated cGMP via guanylyl cyclase-A receptors; however, the 180-minute samples were not active. The proBNP1-108 processing enzyme corin and BNP-degrading enzyme dipeptidyl peptidase-4 were reduced in HF versus normal, perhaps contributing to differential BNP metabolism in HF. CONCLUSIONS Exogenous proBNP1-108 is processed into active BNP1-32 and ultimately degraded in normal circulation. The processing and degradation of BNP molecular forms were altered but complete in HF, which may contribute to the pathophysiology of HF.
Collapse
Affiliation(s)
- Brenda K Huntley
- From the Cardiorenal Research Laboratory, Division of Cardiovascular Disease, Mayo Clinic, Rochester, MN
| | - Sharon M Sandberg
- From the Cardiorenal Research Laboratory, Division of Cardiovascular Disease, Mayo Clinic, Rochester, MN
| | - Denise M Heublein
- From the Cardiorenal Research Laboratory, Division of Cardiovascular Disease, Mayo Clinic, Rochester, MN
| | - S Jeson Sangaralingham
- From the Cardiorenal Research Laboratory, Division of Cardiovascular Disease, Mayo Clinic, Rochester, MN
| | - John C Burnett
- From the Cardiorenal Research Laboratory, Division of Cardiovascular Disease, Mayo Clinic, Rochester, MN
| | - Tomoko Ichiki
- From the Cardiorenal Research Laboratory, Division of Cardiovascular Disease, Mayo Clinic, Rochester, MN.
| |
Collapse
|
19
|
Ichiki T, Huntley BK, Burnett JC. BNP molecular forms and processing by the cardiac serine protease corin. Adv Clin Chem 2013; 61:1-31. [PMID: 24015598 DOI: 10.1016/b978-0-12-407680-8.00001-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The cardiac hormone, B-type natriuretic peptide (BNP), is one of human natriuretic peptides which possesses cardiorenal protective actions and is used as a therapeutic and a biomarker for heart failure (HF). Its prohormone, proBNP1_108, is processed by the proNPs convertases, corin or furin, to inactive NT-proBNP1_76 and active BNP1-32. Paradoxically, circulating NT-proBNP and BNP are elevated in HF leading to the use of BNP as a sensitive and predictive marker of HF. This paradox may be explained by the "nonspecific" nature of conventional assays and/or a relative deficiency state of "active BNP" as characterized by an increase in inactive proBNP_108 and a decrease in active BNP1-32. Therefore, understanding the regulation of proBNP1_108 processing and the role of the convertase corin may be important in understanding the physiology of HF. Corin is expressed in heart and kidney and may play an important role in regulating blood pressure and remodeling of the heart. The processing of proBNP1_108 by corin may be controlled by O-linked glycosylation of proBNP1-108. A potential impairment of proBNP1lo8 processing in HF may be linked to dysregulation of the convertase corin, which may offer therapeutic opportunities to control proBNPlo0s processing and its activation in HF.
Collapse
|
20
|
Welsh P, McMurray JJ. B-type natriuretic peptide and glycaemia: an emerging cardiometabolic pathway? Diabetologia 2012; 55:1240-3. [PMID: 22398647 DOI: 10.1007/s00125-012-2515-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Accepted: 02/01/2012] [Indexed: 11/29/2022]
Abstract
There is emerging evidence of cross-talk between the myocardium and systemic metabolic pathways. In particular, there is interest in the potential metabolic effects of A-type and B-type natriuretic peptides (ANP and BNP), produced in the myocardial tissue in response to ventricular stretch and cardiac overload. This commentary provides an overview of the evidence that natriuretic peptides promote lipolysis and enhance adiponectin production. In addition, we review new and existing evidence that BNP may directly improve glucose control, or else lower glucose indirectly via enhanced capillary permeability or greater renal excretion. Further investigation of the links between natriuretic peptide and glycaemia would seem important given the potential to reveal novel mechanisms to treat diabetes.
Collapse
Affiliation(s)
- P Welsh
- BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, G12 8TA Scotland, UK.
| | | |
Collapse
|
21
|
Höfeld H, Buck F, Middendorff R, Müller D. A novel natriuretic peptide. BMC Pharmacol 2011. [PMCID: PMC3363246 DOI: 10.1186/1471-2210-11-s1-p50] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
|
22
|
Janssen W, Schymura Y, Wietelmann A, Stasch JP, Luitel H, Weissmann N, Ghofrani HA, Grimminger F, Braun T, Seeger W, Schermuly RT. Improvement of right heart structure and function by BAY 41-8543 in pulmonary artery banded mice. BMC Pharmacol 2011. [PMCID: PMC3363277 DOI: 10.1186/1471-2210-11-s1-p79] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
|
23
|
Abstract
Atrial natriuretic peptide, B-type natriuretic peptide and C-type natriuretic peptide constitute a family of three structurally related, but genetically distinct, signaling molecules that regulate the cardiovascular, skeletal, nervous, reproductive and other systems by activating transmembrane guanylyl cyclases and elevating intracellular cGMP concentrations. This review broadly discusses the general characteristics of natriuretic peptides and their cognate signaling receptors, and then specifically discusses the tissue-specific metabolism of natriuretic peptides and their degradation by neprilysin, insulin-degrading enzyme, and natriuretic peptide receptor-C.
Collapse
Affiliation(s)
- Lincoln R Potter
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota-Twin Cities, Minneapolis, MN 55455, USA.
| |
Collapse
|
24
|
Overexpression of Insulin Degrading Enzyme could Greatly Contribute to Insulin Down-regulation Induced by Short-Term Swimming Exercise. Lab Anim Res 2011; 27:29-36. [PMID: 21826157 PMCID: PMC3145980 DOI: 10.5625/lar.2011.27.1.29] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Revised: 02/25/2011] [Accepted: 02/25/2011] [Indexed: 12/17/2022] Open
Abstract
Exercise training is highly correlated with the reduced glucose-stimulated insulin secretion (GSIS), although it enhanced insulin sensitivity, glucose uptake and glucose transporter expression to reduce severity of diabetic symptoms. This study investigated the impact of short-term swimming exercise on insulin regulation in the Goto-Kakizaki (GK) rat as a non-obese model of non-insulin-dependent diabetes mellitus. Wistar (W/S) and GK rats were trained 2 hours daily with the swimming exercise for 4 weeks, and then the changes in the metabolism of insulin and glucose were assessed. Body weight was markedly decreased in the exercised GK rats compare to their non-exercised counterpart, while W/S rats did not show any exercise-related changes. Glucose concentration was not changed by exercise, although impaired glucose tolerance was improved in GK rats 120 min after glucose injection. However, insulin concentration was decreased by swimming exercise as in the decrease of GSIS after running exercise. To identify the other cause for exercise-induced insulin down-regulation, the changes in the levels of key factors involved in insulin production (C-peptide) and clearance (insulin-degrading enzyme; IDE) were measured in W/S and GK rats. The C-peptide level was maintained while IDE expression increased markedly. Therefore, these results showed that insulin down-regulation induced by short-term swimming exercise likely attributes to enhanced insulin clearance via IDE over-expression than by altered insulin production.
Collapse
|
25
|
|
26
|
Ralat LA, Guo Q, Ren M, Funke T, Dickey DM, Potter LR, Tang WJ. Insulin-degrading enzyme modulates the natriuretic peptide-mediated signaling response. J Biol Chem 2010; 286:4670-9. [PMID: 21098034 DOI: 10.1074/jbc.m110.173252] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Natriuretic peptides (NPs) are cyclic vasoactive peptide hormones with high therapeutic potential. Three distinct NPs (ANP, BNP, and CNP) can selectively activate natriuretic peptide receptors, NPR-A and NPR-B, raising the cyclic GMP (cGMP) levels. Insulin-degrading enzyme (IDE) was found to rapidly cleave ANP, but the functional consequences of such cleavages in the cellular environment and the molecular mechanism of recognition and cleavage remain unknown. Here, we show that reducing expression levels of IDE profoundly alters the response of NPR-A and NPR-B to the stimulation of ANP, BNP, and CNP in cultured cells. IDE rapidly cleaves ANP and CNP, thus inactivating their ability to raise intracellular cGMP. Conversely, reduced IDE expression enhances the stimulation of NPR-A and NPR-B by ANP and CNP, respectively. Instead of proteolytic inactivation, IDE cleavage can lead to hyperactivation of BNP toward NPR-A. Conversely, decreasing IDE expression reduces BNP-mediated signaling. Additionally, the cleavages of ANP and BNP by IDE render them active with NPR-B and a reduction of IDE expression diminishes the ability of ANP and BNP to stimulate NPR-B. Our kinetic and crystallographic analyses offer the molecular basis for the selective degradation of NPs and their variants by IDE. Furthermore, our studies reveal how IDE utilizes its catalytic chamber and exosite to engulf and bind up to two NPs leading to biased stochastic, non-sequential cleavages and the ability of IDE to switch its substrate selectivity. Thus, the evolutionarily conserved IDE may play a key role in modulating and reshaping the strength and duration of NP-mediated signaling.
Collapse
Affiliation(s)
- Luis A Ralat
- Ben May Department for Cancer Research, The University of Chicago, Chicago, Illinois 60637, USA
| | | | | | | | | | | | | |
Collapse
|
27
|
Müller D, Greenland KJ, Speth RC, Middendorff R. Neuronal differentiation of NG108-15 cells has impact on nitric oxide- and membrane (natriuretic peptide receptor-A) cyclic GMP-generating proteins. Mol Cell Endocrinol 2010; 320:118-27. [PMID: 20097258 DOI: 10.1016/j.mce.2010.01.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2009] [Revised: 01/14/2010] [Accepted: 01/14/2010] [Indexed: 12/17/2022]
Abstract
Cyclic GMP (cGMP), produced in response to either nitric oxide (NO) or certain peptides, controls important neuronal functions. NG108-15 cells were used to characterize the expression of NO- and cGMP-generating proteins and to identify potential alterations associated with neuronal differentiation (neurite outgrowth). We find that these cells contain exclusively neuronal NO synthase (nNOS) isoforms as well as both NO- (soluble guanylyl cyclase, sGC) and natriuretic peptide- (natriuretic peptide receptor-A, NPR-A) responsive cGMP-producing enzymes. The sGC beta(1) subunit (unlike protein phosphatase 2A subunits) is highly membrane-associated. Membrane concentrations of NPR-A and nNOS, but not sGC beta(1) protein are up-regulated with neuronal differentiation. Intriguingly, the rate of hormone-induced cGMP production by NPR-A is significantly diminished in differentiated cells. These findings support roles for NPR-A, the common receptor of atrial (ANP) and B-type (BNP) natriuretic peptide in mature neurons and provide evidence for pronounced changes in neuronal submembrane cGMP signalling during neuronal differentiation.
Collapse
Affiliation(s)
- Dieter Müller
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, 35385 Giessen, Germany.
| | | | | | | |
Collapse
|
28
|
|
29
|
Chow KM, Gakh O, Payne IC, Juliano MA, Juliano L, Isaya G, Hersh LB. Mammalian pitrilysin: substrate specificity and mitochondrial targeting. Biochemistry 2009; 48:2868-77. [PMID: 19196155 DOI: 10.1021/bi8016125] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The substrate specificity of the mitochondrial metallopeptidase proteinase 1 (MP1) was investigated and its mitochondrial targeting signal identified. The substrate specificity of MP1 was examined with physiological peptides as substrates. Although the enzyme exhibits broad substrate specificity, there is a trend for peptides containing 13 or more residues to exhibit K(m) values of 2 muM or less. Three of four peptides containing 11 or fewer residues exhibited K(m) values above 10 muM. Similarly, peptides containing 13 or more residues exhibited k(cat) values below 10 min(-1), while three of four peptides containing 11 or fewer residues exhibited k(cat) values above 30 min(-1). Many of the peptide cleavage sites of MP1 resemble that of the mitochondrial processing protease (MPP); however, MP1 does not process the precursor form of citrate synthase. The enzyme, however, does cleave the released prepeptide from precitrate synthase. A mitochondria localization was shown in MP1 transfected NT2 and HepG2 cells. Deletion of the N-terminal 15 amino acids caused MP1 to be mislocalized to the cytoplasm and nucleus. Furthermore, when fused to green flourescent protein, this 15-amino acid N-terminal sequence directed the fusion protein to the mitochondria.
Collapse
Affiliation(s)
- K Martin Chow
- Department of Molecular and Cellular Biochemistry, University of Kentucky, B283 BBSRB, 741 South Limestone Street, Lexington, Kentucky 40536-0509, USA
| | | | | | | | | | | | | |
Collapse
|
30
|
Malito E, Hulse RE, Tang WJ. Amyloid beta-degrading cryptidases: insulin degrading enzyme, presequence peptidase, and neprilysin. Cell Mol Life Sci 2008; 65:2574-85. [PMID: 18470479 PMCID: PMC2756532 DOI: 10.1007/s00018-008-8112-4] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The accumulation of aggregates of amyloidogenic peptides is associated with numerous human diseases. One well studied example is the association between deposition of amyloid beta (Abeta) and Alzheimer's disease. Insulin degrading enzyme and neprilysin are involved in the clearance of Abeta, and presequence peptidase is suggested to play a role in the degradation of mitochondrial Abeta. Recent structural analyses reveal that these three peptidases contain a catalytic chamber (crypt) that selectively encapsulates and cleaves amyloidogenic peptides, hence the name cryptidase. The substrate selectivity of these cryptidases is determined by the size and charge distribution of their crypt as well as the conformational flexibility of substrates. The interaction of Abeta with the catalytic core of these cryptidases is controlled by conformational changes that make the catalytic chambers accessible for Abeta binding. These new structural and biochemical insights into cryptidases provide potential therapeutic strategies for the control of Abeta clearance.
Collapse
Affiliation(s)
- E. Malito
- Ben-May Department for Cancer Research, The University of Chicago, 929 East 57th Street, Chicago, IL 60637 United States
| | - R. E. Hulse
- Committee of Neurobiology, The University of Chicago, 947 East 58th Street, Chicago, IL 60637 United States
| | - W.-J. Tang
- Ben-May Department for Cancer Research, The University of Chicago, 929 East 57th Street, Chicago, IL 60637 United States
- Committee of Neurobiology, The University of Chicago, 947 East 58th Street, Chicago, IL 60637 United States
| |
Collapse
|
31
|
Huet Y, Strassner J, Schaller A. Cloning, expression and characterization of insulin-degrading enzyme from tomato (Solanum lycopersicum). Biol Chem 2008; 389:91-8. [PMID: 18095874 DOI: 10.1515/bc.2008.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A cDNA encoding insulin-degrading enzyme (IDE) was cloned from tomato (Solanum lycopersicum) and expressed in Escherichia coli in N-terminal fusion with glutathione S-transferase. GST-SlIDE was characterized as a neutral thiol-dependent metallopeptidase with insulinase activity: the recombinant enzyme cleaved the oxidized insulin B chain at eight peptide bonds, six of which are also targets of human IDE. Despite a certain preference for proline in the vicinity of the cleavage site, synthetic peptides were cleaved at apparently stochastic positions indicating that SlIDE, similar to IDEs from other organisms, does not recognize any particular amino acid motif in the primary structure of its substrates. Under steady-state conditions, an apparent K(m) of 62+/-7 microm and a catalytic efficiency (k(cat)/K(m)) of 62+/-15 mm(-1) s(-1) were determined for Abz-SKRDPPKMQTDLY(NO(3))-NH(2) as the substrate. GST-SlIDE was effectively inhibited by ATP at physiological concentrations, suggesting regulation of its activity in response to the energy status of the cell. While mammalian and plant IDEs share many of their biochemical properties, this similarity does not extend to their function in vivo, because insulin and the beta-amyloid peptide, well-established substrates of mammalian IDEs, as well as insulin-related signaling appear to be absent from plant systems.
Collapse
Affiliation(s)
- Yoann Huet
- Institute of Plant Physiology and Biotechnology, University of Hohenheim, D-70593 Stuttgart, Germany
| | | | | |
Collapse
|
32
|
Song ES, Hersh LB. Insulysin: an allosteric enzyme as a target for Alzheimer's disease. J Mol Neurosci 2005; 25:201-6. [PMID: 15800373 DOI: 10.1385/jmn:25:3:201] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2004] [Accepted: 10/18/2004] [Indexed: 11/11/2022]
Abstract
That the zinc metalloendopeptidase insulysin (insulin-degrading enzyme IDE) is a major b-amyloid (A(beta)) peptide-degrading enzyme in vivo is shown by the higher A(beta) peptide levels in the brain of an insulysin-deficient mouse. Insulysin was shown to initially cleave A(beta)1-40and A(beta)1-42 at His13-Gln14, His14-Gln15, and Phe19-Phe20. The insulysin-dependent cleavage of A(beta) prevents both the neurotoxic effects of the peptide as well as the ability of A(beta) to deposit onto synthetic amyloid plaques. The kinetics of the reaction of insulysin with the synthetic peptide substrate Abz-G-G-F-L-R-K-H-G-Q-EDDnp displays allosteric properties indicative of a regulated enzyme. Small peptide substrates increase the activity of insulysin toward the hydrolysis of A(beta)1-40 without affecting the activity of the enzyme toward insulin. These studies indicate that insulysin is a target for drug development in which small-molecule peptide analogs can be used to increase the rate of A(beta) clearance without affecting insulin levels.
Collapse
Affiliation(s)
- Eun Suk Song
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | | |
Collapse
|
33
|
Song ES, Juliano MA, Juliano L, Hersh LB. Substrate activation of insulin-degrading enzyme (insulysin). A potential target for drug development. J Biol Chem 2003; 278:49789-94. [PMID: 14527953 DOI: 10.1074/jbc.m308983200] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The rate of the insulin-degrading enzyme (IDE)-catalyzed hydrolysis of the fluorogenic substrate 2-aminobenzoyl-GGFLRKHGQ-ethylenediamine-2,4-dinitrophenyl is increased 2-7-fold by other peptide substrates but not by peptide non-substrates. This increased rate is attributed to a decrease in Km with little effect on Vmax. An approximately 2.5-fold increase in the rate of amyloid beta peptide hydrolysis is produced by dynorphin B-9. However, with insulin as substrate, dynorphin B-9 is inhibitory. Immunoprecipitation of differentially tagged IDE and gel filtration analysis were used to show that IDE exists as a mixture of dimers and tetramers. The equilibrium between dimer and tetramer is concentration-dependent, with the dimer the more active form. Bradykinin shifted the equilibrium toward dimer. Activation of substrate hydrolysis is not seen with a mixed dimer of IDE containing one active subunit and one subunit that is catalytically inactive and deficient in substrate binding. On the other hand, a mixed dimer containing one active subunit and one subunit that is catalytically inactive but binds substrate with normal affinity is activated by peptides. These findings suggest that peptides bind to one subunit of IDE and induce a conformational change that shifts the equilibrium to the more active dimer as well as activates the adjacent subunit. The selective activation of IDE toward amyloid beta peptide relative to insulin suggests the potential for development of compounds that increase IDE activity toward amyloid beta peptide as a therapeutic intervention for the treatment of Alzheimer's disease.
Collapse
Affiliation(s)
- Eun-Suk Song
- Department of Molecular and Cellular Biochemistry and the Center for Structural Biology, University of Kentucky, Lexington, Kentucky 40536-0084, USA
| | | | | | | |
Collapse
|
34
|
Abstract
Insulin-degrading enzyme (IDE) is a metalloprotease implicated in insulin degradation and suggested to have a variety of additional functions, including the clearance of amyloid beta peptides of Alzheimer's disease. Little is known about endogenous proteins that may interact with and modulate IDE's activity in the cell. We purified and characterized two proteins from mouse leukemic splenocytes that interact with IDE and inhibit its insulin-degrading activity. A protein of 14 kDa was similar to a competitive IDE inhibitor reported previously. The major inhibitor was identified by amino acid sequencing as ubiquitin, a protein that is post-translationally covalently attached to other intracellular proteins and regulates diverse cellular processes. Ubiquitin inhibited insulin-degrading activity of IDE and diminished crosslinking of 125I-insulin to IDE in a specific, concentration-dependent, reversible, and ATP-independent manner. Ubiquitin did not affect the crosslinking of 125I-insulin to insulin receptors or of 125I-atrial natriuretic peptide (ANP) to its receptor guanylate cyclase-A. These findings suggest a novel role for ubiquitin or perhaps proteins with ubiquitin-like domains in regulating the function of IDE.
Collapse
Affiliation(s)
- Tomo Saric
- Division of Molecular Medicine, Rudjer Boskovic Institute, Bijenicka 54, P.O. Box 180, 10002 Zagreb, Croatia.
| | | | | | | |
Collapse
|
35
|
Boussaha M, Hannequin D, Verpillat P, Brice A, Frebourg T, Campion D. Polymorphisms of insulin degrading enzyme gene are not associated with Alzheimer's disease. Neurosci Lett 2002; 329:121-3. [PMID: 12161276 DOI: 10.1016/s0304-3940(02)00586-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To date, allele 4 of the apolipoprotein E gene is the only risk factor that has been robustly associated with Alzheimer's disease (AD). Identification and molecular characterization of other risk factors is of great interest. The insulin degrading enzyme (IDE) is an attractive candidate gene since: (i), previous studies have identified a possible role that IDE plays in the degradation and clearance of human amyloid beta from migroglial cells and neurons; and (ii), this gene is located on chromosome 10q23-q24, a region in which a susceptibility locus for AD has recently been mapped. In the present study, we have assessed whether IDE is a potential risk factor for AD. Two intronic single nucleotide polymorphisms (SNPs) were genotyped in a case-control study including 388 French individuals. No association between these SNPs and AD was detected.
Collapse
Affiliation(s)
- Mekki Boussaha
- INSERM EMI 9906, IFRMP, Faculté de Médecine et de Pharmacie, 76183 Rouen, France
| | | | | | | | | | | |
Collapse
|
36
|
Song ES, Mukherjee A, Juliano MA, Pyrek JS, Goodman JP, Juliano L, Hersh LB. Analysis of the subsite specificity of rat insulysin using fluorogenic peptide substrates. J Biol Chem 2001; 276:1152-5. [PMID: 11042190 DOI: 10.1074/jbc.m008702200] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Recombinant rat insulysin was shown to cleave the internally quenched fluorogenic peptide 2-aminobenzyl-GGFLRKVGQ-ethylenediamine-2,4-dinitrophenol at the R-K bond, exhibiting a K(m) of 13 microm and a V(max) of 2.6 micromol min(-1) mg(-1). Derivatives of this peptide in which the P(2) leucine or the P(2)' valine were replaced with other residues were used to probe the subsite specificity of the enzyme. Varying the P(2) residue produced a 4-fold range in K(m) and a 7-fold range in k(cat). The nature of the P(2) residue had a significant effect on the site of cleavage. Leucine, isoleucine, valine, and aspartate produced cleavage at the R-K bond. Asparagine produced 36% cleavage at the N-R bond and 64% cleavage at the R-K bond, whereas with alanine or serine the A-R and S-R bonds were the major cleavage sites. With tyrosine, phenylalanine, methionine, or histidine representing the varied residue X, cleavages at F-X, X-R, and R-K were seen, whereas with tryptophan equal cleavage occurred at the F-W and W-R bonds. Variable P(2)' residues produce less of a change in both K(m) and k(cat) and have little influence on the cleavage site. Exceptions are phenylalanine, tyrosine, leucine, and isoleucine, which in addition to producing cleavage at the R-K bond, produce significant cleavage at the L-R bond. Alanine and tyrosine were unique in producing cleavage at the F-L bond. Taken together, these data suggest that insulysin specificity is directed toward the amino side of hydrophobic and basic residues and that the enzyme has an extended substrate binding site.
Collapse
Affiliation(s)
- E S Song
- Department of Biochemistry, University of Kentucky, Lexington, Kentucky 40536-0084, USA
| | | | | | | | | | | | | |
Collapse
|
37
|
Horn S, Meyer J, Heukeshoven J, Fehse B, Schulze C, Li S, Frey J, Poll S, Stocking C, Jücker M. The inositol 5-phosphatase SHIP is expressed as 145 and 135 kDa proteins in blood and bone marrow cells in vivo, whereas carboxyl-truncated forms of SHIP are generated by proteolytic cleavage in vitro. Leukemia 2001; 15:112-20. [PMID: 11243378 DOI: 10.1038/sj.leu.2401990] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The inositol polyphosphate 5-phosphatase SHIP plays an important role in negative signalling in B cells and mast cells and in the down-regulation of cytokine receptor-mediated signals in myeloid cells. SHIP is expressed as a 145 kDa full-length protein and an isoform of 135 kDa due to alternative splicing. Additional smaller forms of SHIP which are truncated at the carboxy terminus have been described in bone marrow and peripheral blood mononuclear cells (PBMC). Our data demonstrate that human bone marrow cells and PBMC from healthy donors and patients with acute myeloid leukemia express the 145 kDa form of SHIP and low amounts of a 135 kDa form of SHIP in vivo whereas C-terminal-truncated SHIP proteins are generated by a PMSF-sensitive protease during the preparation of cell lysates in vitro. We have further characterized this protease and identified a proteolytic cleavage site in the human SHIP protein C-terminal to tryptophan residue 941. These data support a physiological role for the 145 and 135 kDa forms of SHIP in bone marrow and peripheral blood cells from normal donors and patients with acute myeloid leukemia.
Collapse
Affiliation(s)
- S Horn
- Institut für Medizinische Biochemie und Molekularbiologie, Abteilung für Zelluläre Signaltransduktion, Universitäts-Krankenhaus Eppendorf, Universität Hamburg, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Morita M, Kurochkin IV, Motojima K, Goto S, Takano T, Okamura S, Sato R, Yokota S, Imanaka T. Insulin-degrading enzyme exists inside of rat liver peroxisomes and degrades oxidized proteins. Cell Struct Funct 2000; 25:309-15. [PMID: 11235899 DOI: 10.1247/csf.25.309] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Insulin-degrading enzyme (IDE) was detected by immunoblot analysis in highly purified rat liver peroxisomes. IDE in the peroxisomal fraction was resistant to proteolysis by trypsin and chymotrypsin under conditions where the peroxisomal membranes remained intact. After sonication of the peroxisomal fraction, IDE was recovered in the supernatant fraction. Further, the localization of IDE in the peroxisomes was shown by immunoelectron microscopy. In addition, IDE isolated from peroxisomes degraded insulin as well as oxidized lysozyme as a model substrate for oxidized proteins. These results suggest that IDE exists in an active form in the matrix of rat liver peroxisomes and is involved in elimination of oxidized proteins in peroxisomes.
Collapse
Affiliation(s)
- M Morita
- Department of Biological Chemistry, Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, Sugitani, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Chesneau V, Rosner MR. Functional human insulin-degrading enzyme can be expressed in bacteria. Protein Expr Purif 2000; 19:91-8. [PMID: 10833395 DOI: 10.1006/prep.2000.1217] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Insulin-degrading enzyme (IDE) has been shown to degrade a number of biologically important peptides, including insulin and the amyloid-beta protein implicated in Alzheimer's disease. However, lack of a facile method to generate purified enzyme and related mutants has made it difficult to study the precise role of IDE in the clearance of these peptides. Therefore, we determined whether recombinant wild-type and mutant human IDEs can be overexpressed as functional enzymes in bacteria. Three vectors carrying cDNAs encoding N-terminally polyhistidine-tagged recombinant IDEs were constructed, and the proteins expressed in Escherichia coli were purified by metal affinity chromatography (final yield approximately 8 mg per liter of culture). The recombinant IDEs, like the endogenous mammalian enzyme, migrate with 110-kDa apparent molecular masses in SDS-polyacrylamide gels and as a approximately 200-kDa species in gel filtration. Further analysis by native PAGE indicates that IDE can form multimers of different complexities. The wild-type recombinant endopeptidase degrades insulin with an efficiency similar to that of the enzyme purified from mammalian tissues. Purified IDEs are stable at 4 degrees C for at least 1 month. Purified recombinant protein was used to raise specific polyclonal antibodies that can immunoprecipitate native mammalian IDE. Thus, the procedure described allows the rapid production of large amounts of purified IDE and demonstrates that IDE can be produced in an active form in the absence of other potential interacting mammalian proteins.
Collapse
Affiliation(s)
- V Chesneau
- Ben May Institute for Cancer Research, University of Chicago, Illinois 60637, USA
| | | |
Collapse
|
40
|
Clark DJ, Hawrylik SJ, Kavanagh E, Opheim DJ. Purification and characterization of a unique alkaline elastase from Micrococcus luteus. Protein Expr Purif 2000; 18:46-55. [PMID: 10648168 DOI: 10.1006/prep.1999.1166] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Micrococcus luteus isolated from human skin secretes an alkaline protease which degrades elastin. M. luteus protease (MLP) was produced in the late logarithmic and stationary phases of growth. MLP, purified to homogeneity by a three-step process, had a molecular mass of 32,812 Da and an isoelectric point of 9.3. MLP was active and highly stable in solution for 24 h from pH 6.0 to 10.5; it had maximal activity at temperatures between 57 and 59 degrees C. The presence of calcium in the solution was essential for enzyme activity and to prevent autolysis. Optimal activity occurred between pH 9.0 and 9.5, with 60% maximal activity from pH 6.5 to 11.0. The enzyme was inhibited by the serine enzyme inhibitors phenylmethylsulfonyl fluoride and chymostatin but not by the metalloenzyme inhibitor 1,10-phenanthroline or sulfhydryl enzyme inhibitors. Casein, bovine serum albumin, ovalbumin, beta-lactoglobulin, and elastin were digested by the protease while collagen and keratin were resistant to digestion. MLP demonstrated both esterase and amidase activity on synthetic peptide substrates. MLP preferentially cleaved the Leu(15)-Tyr(16) and Phe(24)-Phe(25) bonds of the oxidized beta-chain of insulin. Longer digests of insulin and the pattern of activity against synthetic substrates suggest that MLP has a cleavage specificity for bulky, hydrophobic, or aromatic amino acids in the P(1) or P(1)' positions. Amino acid sequences from the N-terminus and internal peptides of MLP were unique.
Collapse
Affiliation(s)
- D J Clark
- Departments of Biological and Biomedical Sciences, Quinnipiac College, Hamden, Connecticut 06518, USA.
| | | | | | | |
Collapse
|
41
|
Abstract
Insulin degradation is a regulated process that plays a role in controlling insulin action by removing and inactivating the hormone. Abnormalities in insulin clearance and degradation are present in various pathological conditions including type 2 diabetes and obesity and may be important in producing clinical problems. The uptake, processing, and degradation of insulin by cells is a complex process with multiple intracellular pathways. Most evidence supports IDE as the primary degradative mechanism, but other systems (PDI, lysosomes, and other enzymes) undoubtedly contribute to insulin metabolism. Recent studies support a multifunctional role for IDE, as an intracellular binding, regulatory, and degradative protein. IDE increases proteasome and steroid hormone receptor activity, and this activation is reversed by insulin. This raises the possibility of a direct intracellular interaction of insulin with IDE that could modulate protein and fat metabolism. The recent findings would place intracellular insulin-IDE interaction into the insulin signal transduction pathway for mediating the intermediate effects of insulin on fat and protein turnover.
Collapse
Affiliation(s)
- W C Duckworth
- Veterans Affairs Medical Center, Omaha, Nebraska 68105, USA
| | | | | |
Collapse
|
42
|
Towle CA, Wright M, Hecht AC, Kuong SJ, Papanicolas LE, Totkovic R, Mankin HJ, Treadwell BV. A matrix metalloproteinase proenzyme activator produced by articular cartilage. Biochem Biophys Res Commun 1998; 247:324-31. [PMID: 9642125 DOI: 10.1006/bbrc.1998.8781] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Matrix metalloproteinases (MMPs) are involved in connective tissue turnover under physiological and pathological conditions. MMP activity is regulated by the requirement for zymogen activation. This report describes a proMMP-3 activator produced by articular cartilage. The activator initiates a step-wise processing of proMMP-3 to generate an array of active species. Sequencing of activation intermediates demonstrated cleavage on the NH2-terminal side of certain basic residues in the MMP-3 propeptide. Metal ion chelators inhibited activator-dependent proteolysis, and activity was restored by low levels of ZnCl2. These catalytic properties suggest similarity to members of the insulinase superfamily of metalloendopeptidases with in vitro specificity for single arginine or paired basic processing sites in a variety of prohormones. Dibasic sites also exist in the propeptides of several MMPs including proMMP-3. This is the first report that cartilage produces a potent MMP proenzyme activator, opening the possibility of a novel intrinsic activation pathway for catabolic processes in this avascular tissue.
Collapse
Affiliation(s)
- C A Towle
- Orthopaedic Research Laboratories, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, 02114, USA
| | | | | | | | | | | | | | | |
Collapse
|
43
|
Abstract
Insulin-degrading enzyme (IDE) is an evolutionarily conserved neutral thiol metalloprotease expressed in all mammalian tissues whose biological role is not well established. IDE has highly selective substrate specificity. It degrades insulin, glucagon, atrial natriuretic peptide, transforming growth factor alpha but does not act on related hormones and growth factors. The structural properties determining whether a peptide is an IDE substrate are essentially unknown. The reported cleavage sites are not consistent with simple peptide-bond recognition and it was proposed that IDE recognizes in its substrates some elements of tertiary structure. We noticed that although IDE substrates are functionally unrelated, the majority of them share a specific property, an ability to form under certain conditions amyloid fibrils. Utilizing the residue pattern recognition procedure, this study reveals a common motif in the sequences of IDE substrates, HNHHHPSH, where H is wholly or partly hydrophobic character, N is small and neutral, P is polar, and S is polar and/or small amino acid residue. It is proposed that this sequence motif predetermines a structure recognized by IDE. The identified motif appears to be essentially the same as the proposed earlier consensus sequence for amyloid-forming peptides [Turnell and Finch, J. Mol. Biol. 227 (1992) 1205-1223]. The study suggests that IDE may play a role in elimination of potentially toxic amyloidogenic peptides.
Collapse
Affiliation(s)
- I V Kurochkin
- Chugai Research Institute for Molecular Medicine, Inc., Niihari, Ibaraki, Japan.
| |
Collapse
|
44
|
|
45
|
Chesneau V, Perlman RK, Li W, Keller GA, Rosner MR. Insulin-degrading enzyme does not require peroxisomal localization for insulin degradation. Endocrinology 1997; 138:3444-51. [PMID: 9231799 DOI: 10.1210/endo.138.8.5344] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Although considerable evidence implicates insulin-degrading enzyme (IDE) in the cellular metabolism of insulin in many cell types, its mechanism and site of action are not clear. In this study, we have examined the relationship between insulin-degrading enzyme's peroxisomal location and its ability to degrade insulin by mutation of its peroxisomal targeting signal (PTS), the carboxy terminal A/S-K-L tripeptide. Site-directed mutagenesis was used to destroy the peroxisomal targeting signal of human insulin-degrading enzyme by changing alanine to leucine (AL.pts), leucine to valine (LV.pts), or by deleting the entire tripeptide (DEL.pts). The alanine or leucine mutants, when expressed in COS cells, were indistinguishable from wild-type insulin-degrading enzyme with respect to size (110 kDa), amount of immunoreactive material, ability to bind insulin, in vitro activity, and cellular degradation of insulin. In contrast, the deletion mutant was shorter in size (approximately 0 kDa) and unable to bind the hormone. Thus, although the tripeptide at insulin-degrading enzyme's carboxy terminus appeared to confer enzyme stability, the conserved sequence was not required for insulin degradation. Finally, an immunocytofluorescence study showed that, whereas a significant amount of the wild-type protein was localized in peroxisomes, none of the peroxisomal targeting mutants could be detected in these organelles. These findings indicate that insulin-degrading enzyme does not require peroxisomal localization for insulin degradation and suggest that this enzyme has multiple cellular functions.
Collapse
Affiliation(s)
- V Chesneau
- Ben May Institute for Cancer Research, The University of Chicago, Illinois 60637, USA
| | | | | | | | | |
Collapse
|
46
|
Hamel FG, Gehm BD, Rosner MR, Duckworth WC. Identification of the cleavage sites of transforming growth factor alpha by insulin-degrading enzymes. BIOCHIMICA ET BIOPHYSICA ACTA 1997; 1338:207-14. [PMID: 9128138 DOI: 10.1016/s0167-4838(96)00202-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Insulin-degrading enzyme (IDE) is a sulfhydryl-dependent metalloproteinase with a zinc binding site unique to a new class of proteinases. The enzyme is relatively specific for a number of hormones/growth factors, such as insulin, atrial natriuretic peptide, IGF-II, and proinsulin. In this study we have identified the amino-acid bonds cleaved by IDE in transforming growth factor-alpha. High-performance liquid chromatography was used to separate the peptides generated by the degradation of 125I-TGF-alpha. The peptides were then submitted to sequential Edman degradation to determine the peptide bond broken. Cleavage sites were found at amino acids, 10-11 (Asp-Ser), 25-26 (Val-Gln), 28-29 (Asp-Lys), and 30-31 (Pro-Ala). In agreement with studies of cleavage sites of other hormones by this enzyme, no clear amino-acid specificity was seen. However, examination of the sites on a three-dimensional model of TGF-alpha suggest the primary mechanism used by IDE for determining cleavage sites is the tertiary structure of the substrate.
Collapse
Affiliation(s)
- F G Hamel
- University of Nebraska Medical Center, Veteran's Affairs Medical Center, Omaha 68198-3020, USA
| | | | | | | |
Collapse
|
47
|
Abstract
C-type natriuretic peptide is a 22-amino acid peptide that was initially identified in the central nervous system. The distribution of C-type natriuretic peptide, which has structural homology with atrial and brain natriuretic peptides, is wide and includes the endothelium, myocardium, gastrointestinal, and genitourinary tracts. The biological effects of this peptide are being elucidated in a number of sites in a number of species; however, the novel endothelial site of production of C-type natriuretic peptide and the proximal situation of its receptor in vascular smooth muscle suggest that this vascular natriuretic peptide system may play a role in concert with other local systems in the control of vascular tone.
Collapse
Affiliation(s)
- C S Barr
- Department of Pharmacology and Clinical Pharmacology, University of Dundee, Ninewells Hospital and Medical School, Scotland
| | | | | |
Collapse
|
48
|
Aguilar MI, Hearn MT. High-resolution reversed-phase high-performance liquid chromatography of peptides and proteins. Methods Enzymol 1996; 270:3-26. [PMID: 8803962 DOI: 10.1016/s0076-6879(96)70003-4] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- M I Aguilar
- Department of Biochemistry, Monash University, Clayton, Victoria, Australia
| | | |
Collapse
|
49
|
|
50
|
|