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Wong CYJ, Baldelli A, Tietz O, van der Hoven J, Suman J, Ong HX, Traini D. An overview of in vitro and in vivo techniques for characterization of intranasal protein and peptide formulations for brain targeting. Int J Pharm 2024; 654:123922. [PMID: 38401871 DOI: 10.1016/j.ijpharm.2024.123922] [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: 12/07/2023] [Revised: 02/15/2024] [Accepted: 02/18/2024] [Indexed: 02/26/2024]
Abstract
The surge in neurological disorders necessitates innovative strategies for delivering active pharmaceutical ingredients to the brain. The non-invasive intranasal route has emerged as a promising approach to optimize drug delivery to the central nervous system by circumventing the blood-brain barrier. While the intranasal approach offers numerous advantages, the lack of a standardized protocol for drug testing poses challenges to both in vitro and in vivo studies, limiting the accurate interpretation of nasal drug delivery and pharmacokinetic data. This review explores the in vitro experimental assays employed by the pharmaceutical industry to test intranasal formulation. The focus lies on understanding the diverse techniques used to characterize the intranasal delivery of drugs targeting the brain. Parameters such as drug release, droplet size measurement, plume geometry, deposition in the nasal cavity, aerodynamic performance and mucoadhesiveness are scrutinized for their role in evaluating the performance of nasal drug products. The review further discusses the methodology for in vivo characterization in detail, which is essential in evaluating and refining drug efficacy through the nose-to-brain pathway. Animal models are indispensable for pre-clinical drug testing, offering valuable insights into absorption efficacy and potential variables affecting formulation safety. The insights presented aim to guide future research in intranasal drug delivery for neurological disorders, ensuring more accurate predictions of therapeutic efficacy in clinical contexts.
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Affiliation(s)
- Chun Yuen Jerry Wong
- Respiratory Technology, Woolcock Institute of Medical Research, Sydney, NSW 2037, Australia; Faculty of Medicine and Health Sciences, Macquarie Medical School, Macquarie University, Sydney, NSW 2109, Australia
| | - Alberto Baldelli
- Faculty of Food and Land Systems, The University of British Columbia, 2357 Main Mall, Vancouver, BC V6T 1Z4, Canada
| | - Ole Tietz
- Dementia Research Centre, Faculty of Medicine and Health Sciences, Macquarie Medical School, Macquarie University, Sydney, NSW 2109, Australia
| | - Julia van der Hoven
- Dementia Research Centre, Faculty of Medicine and Health Sciences, Macquarie Medical School, Macquarie University, Sydney, NSW 2109, Australia
| | - Julie Suman
- Next Breath, an Aptar Pharma Company, Baltimore, MD 21227, USA
| | - Hui Xin Ong
- Respiratory Technology, Woolcock Institute of Medical Research, Sydney, NSW 2037, Australia; Faculty of Medicine and Health Sciences, Macquarie Medical School, Macquarie University, Sydney, NSW 2109, Australia.
| | - Daniela Traini
- Respiratory Technology, Woolcock Institute of Medical Research, Sydney, NSW 2037, Australia; Faculty of Medicine and Health Sciences, Macquarie Medical School, Macquarie University, Sydney, NSW 2109, Australia.
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Shpakov AO, Zorina II, Derkach KV. Hot Spots for the Use of Intranasal Insulin: Cerebral Ischemia, Brain Injury, Diabetes Mellitus, Endocrine Disorders and Postoperative Delirium. Int J Mol Sci 2023; 24:3278. [PMID: 36834685 PMCID: PMC9962062 DOI: 10.3390/ijms24043278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/27/2023] [Accepted: 01/31/2023] [Indexed: 02/11/2023] Open
Abstract
A decrease in the activity of the insulin signaling system of the brain, due to both central insulin resistance and insulin deficiency, leads to neurodegeneration and impaired regulation of appetite, metabolism, endocrine functions. This is due to the neuroprotective properties of brain insulin and its leading role in maintaining glucose homeostasis in the brain, as well as in the regulation of the brain signaling network responsible for the functioning of the nervous, endocrine, and other systems. One of the approaches to restore the activity of the insulin system of the brain is the use of intranasally administered insulin (INI). Currently, INI is being considered as a promising drug to treat Alzheimer's disease and mild cognitive impairment. The clinical application of INI is being developed for the treatment of other neurodegenerative diseases and improve cognitive abilities in stress, overwork, and depression. At the same time, much attention has recently been paid to the prospects of using INI for the treatment of cerebral ischemia, traumatic brain injuries, and postoperative delirium (after anesthesia), as well as diabetes mellitus and its complications, including dysfunctions in the gonadal and thyroid axes. This review is devoted to the prospects and current trends in the use of INI for the treatment of these diseases, which, although differing in etiology and pathogenesis, are characterized by impaired insulin signaling in the brain.
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Affiliation(s)
- Alexander O. Shpakov
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, 194223 St. Petersburg, Russia
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Gaddam M, Singh A, Jain N, Avanthika C, Jhaveri S, De la Hoz I, Sanka S, Goli SR. A Comprehensive Review of Intranasal Insulin and Its Effect on the Cognitive Function of Diabetics. Cureus 2021; 13:e17219. [PMID: 34540446 PMCID: PMC8442633 DOI: 10.7759/cureus.17219] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/16/2021] [Indexed: 12/01/2022] Open
Abstract
Diabetes mellitus continues to be a disease that affects a good percentage of our population. The majority affected need insulin on a day-to-day basis. Before the invention of the first manufactured insulin in 1978, dealing with diabetes took a significant toll on patient's lives. As technology and human innovation prevail, significant advancements have taken place in managing this chronic disease. Patients have an option to decide their mode of insulin delivery. Intranasal insulin, one such form, has a rapid mode of action while effectively controlling postprandial hyperglycemia. It has also been proven to reduce hypoglycemia and insulin resistance problems, which seem to be the main adverse effects of using conventional insulin regularly. However, due to the large dosages needed and high incurring costs, Intranasal Insulin is currently being used as adjunctive therapy along with conventional insulin. We conducted a literature search in PubMed indexed journals using the medical terms "Intranasal insulin," "diabetes," and "cognitive impairment" to provide an overview of the mechanism of action of Intranasal Insulin, its distinctive cognitive benefits, and how it can be compared to the standard parenteral insulin therapy. One unique feature of intranasal insulin is its ability to directly affect the central nervous system, bypassing the blood-brain barrier. Not only does this help in reducing the peripheral side effects of insulin, but it has also proven to play a role in improving the cognitive function of diabetics, especially those who have Alzheimer's or mild cognitive impairment, as decreased levels of insulin in the brain has been shown to impact cognitive function negatively. However, it does come with its limitations of poor absorption through the nasal mucosa due to mucociliary clearance and proteolytic enzymes, our body's natural defence mechanisms. This review focuses on the efficacy of intranasal insulin, its potential benefits, limitations, and role in cognitive improvement in people with diabetes with pre-existing cognitive impairment.
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Affiliation(s)
| | | | - Nidhi Jain
- Internal Medicine, Sir Ganga Ram Hospital, New Delhi, IND
| | | | - Sharan Jhaveri
- Internal Medicine, Smt. Nathiba Hargovandas Lakhmichand Municipal Medical College, Ahmedabad, IND
| | | | - Sujana Sanka
- Internal Medicine, JC Medical Center, Orlando, USA
| | - Sri Rupa Goli
- Internal Medicine, Shri Sathya Sai Medical College and Research Institute, Chennai, IND
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4
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Abstract
The intranasal (IN) route enables the delivery of insulin to the central nervous system in the relative absence of systemic uptake and related peripheral side effects. Intranasally administered insulin is assumed to travel along olfactory and adjacent pathways and has been shown to rapidly accumulate in cerebrospinal fluid, indicating efficient transport to the brain. Two decades of studies in healthy humans and patients have demonstrated that IN insulin exerts functional effects on metabolism, such as reductions in food intake and body weight and improvements of glucose homeostasis, as well as cognition, ie, enhancements of memory performance both in healthy individuals and patients with mild cognitive impairment or Alzheimer's disease; these studies moreover indicate a favourable safety profile of the acute and repeated use of IN insulin. Emerging findings suggest that IN insulin also modulates neuroendocrine activity, sleep-related mechanisms, sensory perception and mood. Some, but not all studies point to sex differences in the response to IN insulin that need to be further investigated along with the impact of age. "Brain insulin resistance" is an evolving concept that posits impairments in central nervous insulin signalling as a pathophysiological factor in metabolic and cognitive disorders such as obesity, type 2 diabetes and Alzheimer's disease, and, notably, a target of interventions that rely on IN insulin. Still, the negative outcomes of longer-term IN insulin trials in individuals with obesity or Alzheimer's disease highlight the need for conceptual as well as methodological advances to translate the promising results of proof-of-concept experiments and pilot clinical trials into the successful clinical application of IN insulin.
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Affiliation(s)
- Manfred Hallschmid
- Institute of Medical Psychology and Behavioural Neurobiology, University of Tübingen, Tübingen, Germany
- German Centre for Diabetes Research (DZD), Tübingen, Germany
- Institute for Diabetes Research and Metabolic Diseases, Helmholtz Centre Munich at the University of Tübingen, Tübingen, Germany
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Abstract
Brain insulin signaling contributes to memory function and might be a viable target in the prevention and treatment of memory impairments including Alzheimer's disease. This short narrative review explores the potential of central nervous system (CNS) insulin administration via the intranasal pathway to improve memory performance in health and disease, with a focus on the most recent results. Proof-of-concept studies and (pilot) clinical trials in individuals with mild cognitive impairment or Alzheimer's disease indicate that acute and prolonged intranasal insulin administration enhances memory performance, and suggest that brain insulin resistance is a pathophysiological factor in Alzheimer's disease with or without concomitant metabolic dysfunction. Intranasally administered insulin is assumed to trigger improvements in synaptic plasticity and regional glucose uptake as well as alleviations of Alzheimer's disease neuropathology; additional contributions of changes in hypothalamus-pituitary-adrenocortical axis activity and sleep-related mechanisms are discussed. While intranasal insulin delivery has been conclusively demonstrated to be effective and safe, the recent outcomes of large-scale clinical studies underline the need for further investigations, which might also yield new insights into sex differences in the response to intranasal insulin and contribute to the optimization of delivery devices to grasp the full potential of intranasal insulin for Alzheimer's disease.
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Affiliation(s)
- Manfred Hallschmid
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Otfried-Müller-Str. 25, 72076, Tübingen, Germany.
- German Center for Diabetes Research (DZD), Tübingen, Germany.
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany.
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Intranasal insulin therapy reverses hippocampal dendritic injury and cognitive impairment in a model of HIV-associated neurocognitive disorders in EcoHIV-infected mice. AIDS 2019; 33:973-984. [PMID: 30946151 PMCID: PMC6457131 DOI: 10.1097/qad.0000000000002150] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Almost half of HIV-positive people on antiretroviral therapy have demonstrable mild neurocognitive impairment (HIV-NCI), even when virologically suppressed. Intranasal insulin therapy improves cognition in Alzheimer's disease and diabetes. Here we tested intranasal insulin therapy in a model of HIV-NCI in EcoHIV-infected conventional mice. DESIGN AND METHODS Insulin pharmacokinetics following intranasal administration to mice was determined by ELISA. Mice were inoculated with EcoHIV to cause NCI; 23 days or 3 months after infection they were treated daily for 9 days with intranasal insulin (2.4 IU/mouse) and examined for NCI in behavioral tests and HIV burdens by quantitative PCR. Some animals were tested for hippocampal neuronal integrity by immunostaining and expression of neuronal function-related genes by real time-quantitative PCR. The effect of insulin treatment discontinuation on cognition and neuropathology was also examined. RESULTS Intranasal insulin administration to mice resulted in μIU/ml levels of insulin in cerebrospinal fluid with a half-life of about 2 h, resembling pharmacokinetic parameters of patients receiving 40 IU. Intranasal insulin treatment starting 23 days or 3 months after infection completely reversed NCI in mice. Murine NCI correlated with reductions in hippocampal dendritic arbors and downregulation of neuronal function genes; intranasal insulin reversed these changes coincident with restoration of cognitive acuity, but they returned within 24 h of treatment cessation. Intranasal insulin treatment reduced brain HIV DNA when started 23 but not 90 days after infection. CONCLUSION Our preclinical studies support the use of intranasal insulin administration for treatment of HIV-NCI and suggest that some dendritic injury in this condition is reversible.
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Santiago JCP, Hallschmid M. Outcomes and clinical implications of intranasal insulin administration to the central nervous system. Exp Neurol 2019; 317:180-190. [PMID: 30885653 DOI: 10.1016/j.expneurol.2019.03.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 02/12/2019] [Accepted: 03/13/2019] [Indexed: 12/20/2022]
Abstract
Insulin signaling in the brain plays a critical role in metabolic control and cognitive function. Targeting insulinergic pathways in the central nervous system via peripheral insulin administration is feasible, but associated with systemic effects that necessitate tight supervision or countermeasures. The intranasal route of insulin administration, which largely bypasses the circulation and thereby greatly reduces these obstacles, has now been repeatedly tested in proof-of-concept studies in humans as well as animals. It is routinely used in experimental settings to investigate the impact on eating behavior, peripheral metabolism, memory function and brain activation of acute or long-term enhancements in central nervous system insulin signaling. Epidemiological and experimental evidence linking deteriorations in metabolic control such as diabetes with neurodegenerative diseases imply pathophysiological relevance of dysfunctional brain insulin signaling or brain insulin resistance, and suggest that targeting insulin in the brain holds some promise as a therapy or adjunct therapy. This short narrative review gives an overview over recent findings on brain insulin signaling as derived from human studies deploying intranasal insulin, and evaluates the potential of therapeutic interventions that target brain insulin resistance.
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Affiliation(s)
- João C P Santiago
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, 72076 Tübingen, Germany; German Center for Diabetes Research (DZD), 72076 Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, 72076 Tübingen, Germany
| | - Manfred Hallschmid
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, 72076 Tübingen, Germany; German Center for Diabetes Research (DZD), 72076 Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, 72076 Tübingen, Germany.
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Schmid V, Kullmann S, Gfrörer W, Hund V, Hallschmid M, Lipp HP, Häring HU, Preissl H, Fritsche A, Heni M. Safety of intranasal human insulin: A review. Diabetes Obes Metab 2018; 20:1563-1577. [PMID: 29508509 DOI: 10.1111/dom.13279] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 02/26/2018] [Accepted: 02/28/2018] [Indexed: 12/12/2022]
Abstract
AIMS To conduct a review in order to assess the safety of intranasal human insulin in clinical studies as well as the temporal stability of nasal insulin sprays. MATERIAL AND METHODS An electronic search was performed using MEDLINE. We selected original research on intranasal human insulin without further additives in humans. The studies included could be of any design as long as they used human intranasal insulin as their study product. All outcomes and adverse side effects were extracted. RESULTS A total of 38 studies in 1092 individuals receiving acute human intranasal insulin treatment and 18 studies in 832 individuals receiving human intranasal insulin treatment lasting between 21 days and 9.7 years were identified. No cases of symptomatic hypoglycaemia or severe adverse events (AEs) were reported. Transient local side effects in the nasal area were frequently experienced after intranasal insulin and placebo spray, while other AEs were less commonly reported. There were no reports of participants being excluded as a result of AEs. No instances of temporal stability of nasal insulin were reported in the literature. Tests on insulin that had been repacked into spray flasks showed that it had a chemical stability of up to 57 days. CONCLUSIONS Our retrospective review of published studies on intranasal insulin did not reveal any safety concerns; however, there were insufficient data to ensure the long-term safety of this method of chronic insulin administration. Improved insulin preparations that cause less nasal irritation would be desirable for future treatment.
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MESH Headings
- Administration, Intranasal
- Aerosols
- Diabetes Mellitus, Type 1/blood
- Diabetes Mellitus, Type 1/drug therapy
- Diabetes Mellitus, Type 2/blood
- Diabetes Mellitus, Type 2/drug therapy
- Drug Compounding
- Drug Stability
- Humans
- Hyperglycemia/prevention & control
- Hypoglycemia/chemically induced
- Hypoglycemia/prevention & control
- Hypoglycemic Agents/administration & dosage
- Hypoglycemic Agents/adverse effects
- Hypoglycemic Agents/chemistry
- Hypoglycemic Agents/therapeutic use
- Insulin, Regular, Human/administration & dosage
- Insulin, Regular, Human/adverse effects
- Insulin, Regular, Human/chemistry
- Insulin, Regular, Human/therapeutic use
- Protein Stability
- Recombinant Proteins/administration & dosage
- Recombinant Proteins/adverse effects
- Recombinant Proteins/chemistry
- Recombinant Proteins/therapeutic use
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Affiliation(s)
- Vera Schmid
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center, Munich, at the University of Tübingen, Tübingen, Germany
- German Centre for Diabetes Research (DZD e.V.), Tübingen, Germany
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Stephanie Kullmann
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center, Munich, at the University of Tübingen, Tübingen, Germany
- German Centre for Diabetes Research (DZD e.V.), Tübingen, Germany
| | | | - Verena Hund
- University Pharmacy, University Hospital, Tübingen, Germany
| | - Manfred Hallschmid
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center, Munich, at the University of Tübingen, Tübingen, Germany
- German Centre for Diabetes Research (DZD e.V.), Tübingen, Germany
- Institute of Medical Psychology and Behavioral Neurobiology, Eberhard Karls University Tübingen, Tübingen, Germany
| | | | - Hans-Ulrich Häring
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center, Munich, at the University of Tübingen, Tübingen, Germany
- German Centre for Diabetes Research (DZD e.V.), Tübingen, Germany
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Hubert Preissl
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center, Munich, at the University of Tübingen, Tübingen, Germany
- German Centre for Diabetes Research (DZD e.V.), Tübingen, Germany
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University Tübingen, Tübingen, Germany
- Institute for Diabetes and Obesity, Helmholtz Diabetes Centre at Helmholtz Zentrum München, German Research Centre for Environmental Health (GmbH), Neuherberg, Germany
- Institute of Pharmaceutical Sciences, Department of Pharmacy and Biochemistry, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Andreas Fritsche
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center, Munich, at the University of Tübingen, Tübingen, Germany
- German Centre for Diabetes Research (DZD e.V.), Tübingen, Germany
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Martin Heni
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center, Munich, at the University of Tübingen, Tübingen, Germany
- German Centre for Diabetes Research (DZD e.V.), Tübingen, Germany
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University Tübingen, Tübingen, Germany
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Avgerinos KI, Kalaitzidis G, Malli A, Kalaitzoglou D, Myserlis PG, Lioutas VA. Intranasal insulin in Alzheimer's dementia or mild cognitive impairment: a systematic review. J Neurol 2018; 265:1497-1510. [PMID: 29392460 PMCID: PMC6465964 DOI: 10.1007/s00415-018-8768-0] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 01/22/2018] [Accepted: 01/23/2018] [Indexed: 12/30/2022]
Abstract
BACKGROUND AND AIMS Due to common pathophysiological findings of Alzheimer's disease (AD) with diabetes mellitus (DM), insulin has been suggested as a possible treatment of AD or mild cognitive impairment (MCI). A safe alternative of IV insulin is intranasal (IN) insulin. The aim of this systematic review is to investigate the effects of IN insulin on cognitive function of patients with either AD or MCI. METHODS A literature search of the electronic databases Medline, Scopus and CENTRAL was performed to identify RCTs investigating the effect of IN insulin administration on cognitive tasks, in patients with AD or MCI. RESULTS Seven studies (293 patients) met our inclusion criteria. Most studies showed that verbal memory and especially story recall was improved after IN insulin administration. Sometimes the effect was restricted for apoe4 (-) patients. Intranasal insulin did not affect other cognitive functions. However, there were some positive results in functional status and daily activity. Data suggested that different insulin types and doses may have different effects on different apoe4 groups. In addition, the effects of treatment on Αβ levels differed from study to study. Finally, IN insulin resulted in minor adverse effects. CONCLUSIONS Intranasal insulin improved story recall performance of apoe4 (-) patients with AD or MCI. Other cognitive functions were not affected, but there were some positive results in functional status and daily activity. Since IN insulin is a safe intervention, future studies should be conducted with larger doses and after proper selection of patients and insulin types.
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Affiliation(s)
- Konstantinos Ioannis Avgerinos
- 251 Hellenic Airforce General Hospital, Kanellopoulou 3, 11525, Athens, Greece.
- Department of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece.
- Society of Junior Doctors, Athens, Greece.
| | - Grigorios Kalaitzidis
- Department of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
- Society of Junior Doctors, Athens, Greece
| | - Antonia Malli
- Faculty of Medicine, National and Kapodistrian University of Athens, Athens, Greece
- Society of Junior Doctors, Athens, Greece
| | - Dimitrios Kalaitzoglou
- Faculty of Medicine, National and Kapodistrian University of Athens, Athens, Greece
- Society of Junior Doctors, Athens, Greece
| | - Pavlos Gr Myserlis
- 401 General Army Hospital, Athens, Greece
- Society of Junior Doctors, Athens, Greece
| | - Vasileios-Arsenios Lioutas
- Department of Neurology, Division of Cerebrovascular Diseases, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, USA
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Benedict C, Grillo CA. Insulin Resistance as a Therapeutic Target in the Treatment of Alzheimer's Disease: A State-of-the-Art Review. Front Neurosci 2018; 12:215. [PMID: 29743868 PMCID: PMC5932355 DOI: 10.3389/fnins.2018.00215] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 03/19/2018] [Indexed: 01/10/2023] Open
Abstract
Research in animals and humans has shown that type 2 diabetes and its prodromal state, insulin resistance, promote major pathological hallmarks of Alzheimer's disease (AD), such as the formation of amyloid plaques and neurofibrillary tangles (NFT). Worrisomely, dysregulated amyloid beta (Aβ) metabolism has also been shown to promote central nervous system insulin resistance; although the role of tau metabolism remains controversial. Collectively, as proposed in this review, these findings suggest the existence of a mechanistic interplay between AD pathogenesis and disrupted insulin signaling. They also provide strong support for the hypothesis that pharmacologically restoring brain insulin signaling could represent a promising strategy to curb the development and progression of AD. In this context, great hopes have been attached to the use of intranasal insulin. This drug delivery method increases cerebrospinal fluid concentrations of insulin in the absence of peripheral side effects, such as hypoglycemia. With this in mind, the present review will also summarize current knowledge on the efficacy of intranasal insulin to mitigate major pathological symptoms of AD, i.e., cognitive impairment and deregulation of Aβ and tau metabolism.
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Affiliation(s)
| | - Claudia A Grillo
- Department of Pharmacology, Physiology and Neuroscience, University of South Carolina-School of Medicine, Columbia, SC, United States
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Abstract
Although an association between diabetes mellitus (DM) and cognitive dysfunction has been recognized for a century, it is often not considered as a complication of DM and remains under-recognized. Cognitive dysfunction, usually present as mild cognitive impairment, can occur with either type 1 or type 2 DM. Both forms of DM contribute to accelerated cerebral atrophy and to the presence of heightened white matter abnormalities. These effects are noted most at the two extremes of life, in childhood and in the advanced years. The cognitive spheres most affected include attention and executive function, processing speed, perception, and memory. Although DM is unlikely to lead to frank dementia, its ability to exacerbate existing neurodegenerative processes, such as Alzheimer disease, will impact tremendously upon our society in the upcoming decades as our population ages. This chapter describes the clinical impact of DM upon the brain, along with discussion of the potential therapeutic avenues to be discovered in the coming decades. We need to prepare for better preventative and therapeutic management of this cerebral neurodegenerative condition.
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Affiliation(s)
- Cory Toth
- Department of Clinical Neurosciences and Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.
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Haller MJ, Schatz DA. The DIPP project: 20 years of discovery in type 1 diabetes. Pediatr Diabetes 2016; 17 Suppl 22:5-7. [PMID: 27411430 DOI: 10.1111/pedi.12398] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 04/15/2016] [Indexed: 12/24/2022] Open
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Lernmark Å. Environmental factors in the etiology of type 1 diabetes, celiac disease, and narcolepsy. Pediatr Diabetes 2016; 17 Suppl 22:65-72. [PMID: 27411439 PMCID: PMC5473290 DOI: 10.1111/pedi.12390] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 02/25/2016] [Accepted: 03/23/2016] [Indexed: 01/02/2023] Open
Abstract
The etiology of human leukocyte antigen (HLA)-associated organ-specific autoimmune diseases is incomplete. In type 1 diabetes and celiac disease, the strongest associations are with the HLA-DR3-DQ2 and DR4-DQ8 haplotypes, whereas the DQB1*06:02 allele has a strong negative association. In contrast, narcolepsy, especially as recently triggered by the Pandemrix(®) H1N1 vaccine (GlaxoKlineSmith (GSK), Brentford, Middlesex, UK), did not seem to develop without at least one copy of the latter allele. The overall hypothesis is that the role of these different HLA haplotypes, especially in Finland and Sweden, is related to the immune response to infectious agents that are common in these two populations. The high incidence of both type 1 diabetes and celiac disease in Scandinavia may be the result of the HLA-DR3-DQ2 and DR4-DQ8 haplotypes, and the DQB1*06:02 allele are common because they protected people from succumbing to common infections. The timing of dissecting the autoimmune response is critical to understand the possible role of environmental factors. First, an etiological trigger may be a common virus infecting beta cells or with antigens inducing beta-cell cross reactivity. Second, an autoimmune reaction may ensue, perhaps in response to beta-cell apoptosis or autophagy, resulting in autoantigen-specific T cells and autoantibodies. It is critical in at-risk children to dissect the immune response prior to the appearance of autoantibodies in order to identify cellular reactions in response to environmental factors that are able to induce an HLA-associated immune reaction.
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Affiliation(s)
- Åke Lernmark
- Department of Clinical Sciences, Lund University, Malmö, Sweden
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14
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Ribarič S. The Rationale for Insulin Therapy in Alzheimer's Disease. Molecules 2016; 21:molecules21060689. [PMID: 27240327 PMCID: PMC6273626 DOI: 10.3390/molecules21060689] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 05/14/2016] [Accepted: 05/19/2016] [Indexed: 12/30/2022] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia, with a prevalence that increases with age. By 2050, the worldwide number of patients with AD is projected to reach more than 140 million. The prominent signs of AD are progressive memory loss, accompanied by a gradual decline in cognitive function and premature death. AD is the clinical manifestation of altered proteostasis. The initiating step of altered proteostasis in most AD patients is not known. The progression of AD is accelerated by several chronic disorders, among which the contribution of diabetes to AD is well understood at the cell biology level. The pathological mechanisms of AD and diabetes interact and tend to reinforce each other, thus accelerating cognitive impairment. At present, only symptomatic interventions are available for treating AD. To optimise symptomatic treatment, a personalised therapy approach has been suggested. Intranasal insulin administration seems to open the possibility for a safe, and at least in the short term, effective symptomatic intervention that delays loss of cognition in AD patients. This review summarizes the interactions of AD and diabetes from the cell biology to the patient level and the clinical results of intranasal insulin treatment of cognitive decline in AD.
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Affiliation(s)
- Samo Ribarič
- Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Zaloška 4, SI-1000 Ljubljana, Slovenia.
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15
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Abstract
Research in animals and humans has associated Alzheimer's disease (AD) with decreased cerebrospinal fluid levels of insulin in combination with decreased insulin sensitivity (insulin resistance) in the brain. This phenomenon is accompanied by attenuated receptor expression of insulin and insulin-like growth factor, enhanced serine phosphorylation of insulin receptor substrate-1, and impaired transport of insulin across the blood-brain barrier. Moreover, clinical trials have demonstrated that intranasal insulin improves both memory performance and metabolic integrity of the brain in patients suffering from AD or its prodrome, mild cognitive impairment. These results, in conjunction with the finding that insulin mitigates hippocampal synapse vulnerability to beta amyloid, a peptide thought to be causative in the development of AD, provide a strong rationale for hypothesizing that pharmacological strategies bolstering brain insulin signaling, such as intranasal administration of insulin, could have significant potential in the treatment and prevention of AD. With this view in mind, the review at hand will present molecular mechanisms potentially underlying the memory-enhancing and neuroprotective effects of intranasal insulin. Then, we will discuss the results of intranasal insulin studies that have demonstrated that enhancing brain insulin signaling improves memory and learning processes in both cognitively healthy and impaired humans. Finally, we will provide an overview of neuroimaging studies indicating that disturbances in insulin metabolism--such as insulin resistance in obesity, type 2 diabetes and AD--and altered brain responses to insulin are linked to decreased cerebral volume and especially to hippocampal atrophy.
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16
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Ludwig B, Barthel A, Reichel A, Block NL, Ludwig S, Schally AV, Bornstein SR. Modulation of the pancreatic islet-stress axis as a novel potential therapeutic target in diabetes mellitus. VITAMINS AND HORMONES 2014; 95:195-222. [PMID: 24559919 DOI: 10.1016/b978-0-12-800174-5.00008-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Loss of pancreatic islet function and insulin-producing beta cell mass is a central hallmark in the pathogenesis of both type 1 and type 2 diabetes. While in type 1 diabetes this phenomenon is due to an extensive destruction of beta cells caused by an autoimmune process, the mechanisms resulting in beta cell failure in type 2 diabetes are different and less clear. Also, beta cell destruction in type 1 diabetes occurs early and is the initial step in the pathogenetic process, while beta cell loss in type 2 diabetes after an initial phase of hyperinsulinemia due to the underlying insulin resistance occurs relatively late and it is less pronounced. Since diabetes mellitus is the most frequent endocrine disease, with an increasing high prevalence worldwide, huge efforts have been made over the past many decades to identify predisposing genetic, environmental, and nutritional factors in order to develop effective strategies to prevent the disease. In parallel, extensive studies in different cell systems and animal models have helped to elucidate our understanding of the physiologic function of islets and to gain insight into the immunological and non-immunological mechanisms of beta cell destruction and failure. Furthermore, currently emerging concepts of beta cell regeneration (e.g., the restoration of the beta cell pool by regenerative, proliferative and antiapoptotic processes, and recovery of physiologic islet function) apparently is yielding the first promising results. Recent insights into the complex endocrine and paracrine mechanisms regulating the physiologic function of pancreatic islets, as well as beta cell life and death, constitute an essential part of this new and exciting area of diabetology. For example, understanding of the physiological role of glucagon-like peptide 1 has resulted in the successful clinical implementation of incretin-based therapies over the last years. Further, recent data suggesting paracrine effects of growth hormone-releasing hormone and corticotropin-releasing hormone on the regulation of pancreatic islet function, survival, and proliferation as well as on local glucocorticoid metabolism provide evidence for a potential role of the pancreatic islet-stress axis in the pathophysiology of diabetes mellitus. In this chapter, we provide a comprehensive overview of current preventive and regenerative concepts as a basis for the development of novel therapeutic approaches to the treatment of diabetes mellitus. A particular focus is given on the potential of the pancreatic islet-stress axis in the development of novel regenerative strategies.
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Affiliation(s)
- Barbara Ludwig
- Department of Medicine III, University Hospital Carl Gustav Carus, Dresden, Germany; The Paul Langerhans Institute, Dresden, Germany; Center for Regenerative Therapies Dresden, Dresden University of Technology, Dresden, Germany.
| | - Andreas Barthel
- Department of Medicine III, University Hospital Carl Gustav Carus, Dresden, Germany; Endokrinologikum Ruhr, Bochum, Germany
| | - Andreas Reichel
- Department of Medicine III, University Hospital Carl Gustav Carus, Dresden, Germany
| | - Norman L Block
- Department of Pathology, University of Miami Miller School of Medicine, Miami, Florida, USA; Department of Medicine, Division of Hematology-Oncology, University of Miami Miller School of Medicine, Miami, Florida, USA; Veterans Administration Medical Center, Miami, Florida, USA
| | - Stefan Ludwig
- Department of Visceral, Thorax and Vascular Surgery, University Hospital Carl Gustav Carus, Dresden, Germany
| | - Andrew V Schally
- Department of Pathology, University of Miami Miller School of Medicine, Miami, Florida, USA; Department of Medicine, Division of Endocrinology, University of Miami Miller School of Medicine, Miami, Florida, USA; Department of Medicine, Division of Hematology-Oncology, University of Miami Miller School of Medicine, Miami, Florida, USA; Veterans Administration Medical Center, Miami, Florida, USA
| | - Stefan R Bornstein
- Department of Medicine III, University Hospital Carl Gustav Carus, Dresden, Germany; The Paul Langerhans Institute, Dresden, Germany; Center for Regenerative Therapies Dresden, Dresden University of Technology, Dresden, Germany
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17
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Gottlieb P, Utz PJ, Robinson W, Steinman L. Clinical optimization of antigen specific modulation of type 1 diabetes with the plasmid DNA platform. Clin Immunol 2013; 149:297-306. [PMID: 24094739 DOI: 10.1016/j.clim.2013.08.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Accepted: 08/08/2013] [Indexed: 12/16/2022]
Abstract
Some clinical trials in humans have aimed at modulation of type 1 diabetes (T1D) via alteration of the immune response to putative islet cell antigens, particularly proinsulin and insulin, glutamic acid decarboxylase and the peptide, DiaPep 277, derived from heat shock protein 60. The focus here is on development of a specially engineered DNA plasmid encoding proinsulin to treat T1D. The plasmid is engineered to turn off adaptive immunity to proinsulin. This approach yielded exciting results in a randomized placebo controlled trial in 80 adult patients with T1D. The implications of this trial are explored in regards to the potential for sparing inflammation in islets and thus allowing the functioning beta cells to recover and produce more insulin. Strategies to further strengthen the effects seen thus far with the tolerizing DNA plasmid to proinsulin will be elucidated. The DNA platform affords an opportunity for easy modifications. In addition standard exploration of dose levels, route of administration and frequency of dose are practical. Optimization of the effects seen to date on C-peptide and on depletion of proinsulin specific CD8 T cells are feasible, with expected concomitant improvement in other parameters like hemoglobin A1c and reduction in insulin usage. T1D is one of the few autoimmune conditions where antigen specific therapy can be achieved, provided the approach is tested intelligently. Tolerizing DNA vaccines to proinsulin and other islet cell autoantigens is a worthy pursuit to potentially treat, prevent and to perhaps even 'cure' or 'prevent' type 1 diabetes.
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Affiliation(s)
- Peter Gottlieb
- Barbara Davis Center for Childhood Diabetes, Aurora, CO 80045-6511, USA
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18
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Roep BO, Solvason N, Gottlieb PA, Abreu JRF, Harrison LC, Eisenbarth GS, Yu L, Leviten M, Hagopian WA, Buse JB, von Herrath M, Quan J, King RS, Robinson WH, Utz PJ, Garren H, Steinman L. Plasmid-encoded proinsulin preserves C-peptide while specifically reducing proinsulin-specific CD8⁺ T cells in type 1 diabetes. Sci Transl Med 2013; 5:191ra82. [PMID: 23803704 PMCID: PMC4516024 DOI: 10.1126/scitranslmed.3006103] [Citation(s) in RCA: 123] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In type 1 diabetes (T1D), there is an intense inflammatory response that destroys the β cells in the pancreatic islets of Langerhans, the site where insulin is produced and released. A therapy for T1D that targets the specific autoimmune response in this disease while leaving the remainder of the immune system intact, has long been sought. Proinsulin is a major target of the adaptive immune response in T1D. We hypothesized that an engineered DNA plasmid encoding proinsulin (BHT-3021) would preserve β cell function in T1D patients through reduction of insulin-specific CD8⁺ T cells. We studied 80 subjects over 18 years of age who were diagnosed with T1D within the past 5 years. Subjects were randomized 2:1 to receive intramuscular injections of BHT-3021 or BHT-placebo, weekly for 12 weeks, and then monitored for safety and immune responses in a blinded fashion. Four dose levels of BHT-3021 were evaluated: 0.3, 1.0, 3.0, and 6.0 mg. C-peptide was used both as an exploratory efficacy measure and as a safety measure. Islet-specific CD8⁺ T cell frequencies were assessed with multimers of monomeric human leukocyte antigen class I molecules loaded with peptides from pancreatic and unrelated antigens. No serious adverse events related to BHT-3021 were observed. C-peptide levels improved relative to placebo at all doses, at 1 mg at the 15-week time point (+19.5% BHT-3021 versus -8.8% BHT-placebo, P < 0.026). Proinsulin-reactive CD8⁺ T cells, but not T cells against unrelated islet or foreign molecules, declined in the BHT-3021 arm (P < 0.006). No significant changes were noted in interferon-γ, interleukin-4 (IL-4), or IL-10 production in CD4 T cells. Thus, we demonstrate that a plasmid encoding proinsulin reduces the frequency of CD8⁺ T cells reactive to proinsulin while preserving C-peptide over the course of dosing.
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Affiliation(s)
- Bart O. Roep
- Department for Immunohematology and Blood Transfusion, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Nanette Solvason
- Bayhill Therapeutics, Palo Alto, CA 94304, USA
- Foothill College, Los Altos, CA 94022, USA
| | - Peter A. Gottlieb
- Barbara Davis Center for Childhood Diabetes, Aurora, CO 80045–6511, USA
| | - Joana R. F. Abreu
- Department for Immunohematology and Blood Transfusion, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Leonard C. Harrison
- Division of Molecular Medicine, Walter and Eliza Hall Institute for Medical Research, Parkville, Victoria 3052, Australia
| | | | - Liping Yu
- Barbara Davis Center for Childhood Diabetes, Aurora, CO 80045–6511, USA
| | | | - William A. Hagopian
- Pacific Northwest Diabetes Research Institute and University of Washington, Seattle, WA 98122, USA
| | - John B. Buse
- Diabetes Center for Research, University of North Carolina, Chapel Hill, NC 27599, USA
| | | | - Joanne Quan
- Bayhill Therapeutics, Palo Alto, CA 94304, USA
| | | | - William H. Robinson
- Bayhill Therapeutics, Palo Alto, CA 94304, USA
- Departments of Medicine and Neurological Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA
- Tolerion Inc., 321 Dedalera Drive, Portola Valley, CA 94028, USA
| | - Paul J. Utz
- Bayhill Therapeutics, Palo Alto, CA 94304, USA
- Departments of Medicine and Neurological Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA
- Tolerion Inc., 321 Dedalera Drive, Portola Valley, CA 94028, USA
| | - Hideki Garren
- Bayhill Therapeutics, Palo Alto, CA 94304, USA
- Tolerion Inc., 321 Dedalera Drive, Portola Valley, CA 94028, USA
| | | | - Lawrence Steinman
- Bayhill Therapeutics, Palo Alto, CA 94304, USA
- Departments of Medicine and Neurological Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA
- Tolerion Inc., 321 Dedalera Drive, Portola Valley, CA 94028, USA
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19
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von Herrath M, Peakman M, Roep B. Progress in immune-based therapies for type 1 diabetes. Clin Exp Immunol 2013; 172:186-202. [PMID: 23574316 DOI: 10.1111/cei.12085] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/30/2013] [Indexed: 01/10/2023] Open
Abstract
Immune-based therapies that prevent type 1 diabetes or preserve metabolic function remaining at diagnosis have become a major objective for funding agencies and international trial consortia, and receive backing from notable patient advocate groups. The development of immune-based therapeutic strategies in this arena requires a careful balancing of the risks of the therapy against the potential benefits, because many individuals are diagnosed or identified as being at increased risk of disease in early childhood, a period when manipulation of the developing immune system should be undertaken with caution. In addition, a therapy exists (daily insulin injection) that is life-saving in the acute stages of disease and can be used effectively over a lifetime as maintenance. Conversely, the disease is increasing in incidence; is peaking in ever-younger age groups; carries significant risk of increased morbidity and early mortality; and remains difficult to manage effectively in many settings. With these issues in mind, in this article we review progress towards immune-based strategies for this chronic autoimmune disease.
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Affiliation(s)
- M von Herrath
- Center for Type 1 Diabetes Research, La Jolla Institute for Allergy and Immunology, La Jolla, CA, USA
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20
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Gastrointestinal Tract and Endocrine System. Regen Med 2013. [DOI: 10.1007/978-94-007-5690-8_39] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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21
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Freiherr J, Hallschmid M, Frey WH, Brünner YF, Chapman CD, Hölscher C, Craft S, De Felice FG, Benedict C. Intranasal insulin as a treatment for Alzheimer's disease: a review of basic research and clinical evidence. CNS Drugs 2013; 27:505-14. [PMID: 23719722 PMCID: PMC3709085 DOI: 10.1007/s40263-013-0076-8] [Citation(s) in RCA: 343] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Research in animals and humans has associated Alzheimer's disease (AD) with decreased cerebrospinal fluid levels of insulin in combination with decreased insulin sensitivity (insulin resistance) in the brain. This phenomenon is accompanied by attenuated receptor expression of insulin and insulin-like growth factor, enhanced serine phosphorylation of insulin receptor substrate-1, and impaired transport of insulin across the blood-brain barrier. Moreover, clinical trials have demonstrated that intranasal insulin improves both memory performance and metabolic integrity of the brain in patients suffering from AD or its prodrome, mild cognitive impairment. These results, in conjunction with the finding that insulin mitigates hippocampal synapse vulnerability to beta amyloid, a peptide thought to be causative in the development of AD, provide a strong rationale for hypothesizing that pharmacological strategies bolstering brain insulin signaling, such as intranasal administration of insulin, could have significant potential in the treatment and prevention of AD. With this view in mind, the review at hand will present molecular mechanisms potentially underlying the memory-enhancing and neuroprotective effects of intranasal insulin. Then, we will discuss the results of intranasal insulin studies that have demonstrated that enhancing brain insulin signaling improves memory and learning processes in both cognitively healthy and impaired humans. Finally, we will provide an overview of neuroimaging studies indicating that disturbances in insulin metabolism--such as insulin resistance in obesity, type 2 diabetes and AD--and altered brain responses to insulin are linked to decreased cerebral volume and especially to hippocampal atrophy.
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Affiliation(s)
- Jessica Freiherr
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany.
| | - Manfred Hallschmid
- Department of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany ,Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Centre Munich at the University of Tübingen (Paul Langerhans Institute Tübingen), Tübingen, Germany
| | - William H. Frey
- Alzheimer’s Research Center of the HealthPartner’s Center for Memory and Aging, St. Paul, MN USA
| | - Yvonne F. Brünner
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany
| | | | | | - Suzanne Craft
- J. Paul Sticht Center on Aging, Department of Medicine, Wake Forest University School of Medicine, Winston-Salem, NC USA
| | - Fernanda G. De Felice
- Institute of Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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22
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Gan MJ, Albanese-O'Neill A, Haller MJ. Type 1 diabetes: current concepts in epidemiology, pathophysiology, clinical care, and research. Curr Probl Pediatr Adolesc Health Care 2012; 42:269-91. [PMID: 23046732 DOI: 10.1016/j.cppeds.2012.07.002] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Type 1 diabetes (T1D) is an autoimmune disease mediated by a combination of genetic and environmental triggers resulting in lymphocytic infiltration of pancreatic islets, destruction of beta cells, and lifelong dependency on exogenous insulin. Although T1D is prevalent (1 in 300) and its incidence is steadily increasing worldwide (3% per year), the exact gene-environment interactions precipitating the disease remain unknown. Living with T1D is challenging for patients, families, and caregivers. Because of the relative paucity of pediatric endocrinologists, general pediatricians and other subspecialists may occasionally be faced with the task of managing diabetes-related complaints. Herein, we provide a comprehensive review of the natural history, pathophysiology, and contemporary management of T1D. In addition, recent advances in T1D research are discussed.
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Affiliation(s)
- Mary Joyce Gan
- Department of Pediatrics, University of Florida, Gainesville, FL, USA
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23
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Hinke SA. Inverse vaccination with islet autoantigens to halt progression of autoimmune diabetes. Drug Dev Res 2011. [DOI: 10.1002/ddr.20488] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Sprangers B, Van der Schueren B, Gillard P, Mathieu C. Otelixizumab in the treatment of Type 1 diabetes mellitus. Immunotherapy 2011; 3:1303-16. [DOI: 10.2217/imt.11.123] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Anti-CD3 antibodies have been demonstrated in both animal and human studies to be able to reverse autoimmune diseases; for example Type 1 diabetes. Not only does treatment with anti-CD3 antibodies result in the removal of pathogenic T cells but evidence suggests that a state of operational tolerance can be induced through the effects on regulatory T cells. The clinical use of anti-CD3 antibodies has been hampered by their safety profile. However, the introduction of humanized, nonmitogenic, aglycosylated anti-CD3 antibodies, such as otelixizumab, and promising results reported in newly-diagnosed patients with Type 1 diabetes, have renewed the interest for these antibodies in the treatment of autoimmune diseases.
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Affiliation(s)
- Ben Sprangers
- Laboratory of Experimental Transplantation, University of Leuven, Leuven, Belgium. University Hospitals Leuven, Herestraat 49 bus 811, B-3000 Leuven, Belgium
| | - Bart Van der Schueren
- Department of Endocrinology, University Hospitals Leuven, Herestraat 49, B-3000 Leuven, Belgium
- Laboratory of Experimental Medicine & Endocrinology, University of Leuven, Leuven, Belgium. University Hospitals Leuven, Herestraat 49, B-3000 Leuven, Belgium
| | - Pieter Gillard
- Department of Endocrinology, University Hospitals Leuven, Herestraat 49, B-3000 Leuven, Belgium
- Laboratory of Experimental Medicine & Endocrinology, University of Leuven, Leuven, Belgium. University Hospitals Leuven, Herestraat 49, B-3000 Leuven, Belgium
| | - Chantal Mathieu
- Department of Endocrinology, University Hospitals Leuven, Herestraat 49, B-3000 Leuven, Belgium
- Laboratory of Experimental Medicine & Endocrinology, University of Leuven, Leuven, Belgium. University Hospitals Leuven, Herestraat 49, B-3000 Leuven, Belgium
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25
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Fousteri G, Chan JR, Zheng Y, Whiting C, Dave A, Bresson D, Croft M, von Herrath M. Virtual optimization of nasal insulin therapy predicts immunization frequency to be crucial for diabetes protection. Diabetes 2010; 59:3148-58. [PMID: 20864513 PMCID: PMC2992777 DOI: 10.2337/db10-0561] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVE Development of antigen-specific strategies to treat or prevent type 1 diabetes has been slow and difficult because of the lack of experimental tools and defined biomarkers that account for the underlying therapeutic mechanisms. RESEARCH DESIGN AND METHODS The type 1 diabetes PhysioLab platform, a large-scale mathematical model of disease pathogenesis in the nonobese diabetic (NOD) mouse, was used to investigate the possible mechanisms underlying the efficacy of nasal insulin B:9-23 peptide therapy. The experimental aim was to evaluate the impact of dose, frequency of administration, and age at treatment on Treg induction and optimal therapeutic outcome. RESULTS In virtual NOD mice, treatment efficacy was predicted to depend primarily on the immunization frequency and stage of the disease and to a lesser extent on the dose. Whereas low-frequency immunization protected from diabetes atrributed to Treg and interleukin (IL)-10 induction in the pancreas 1-2 weeks after treatment, high-frequency immunization failed. These predictions were confirmed with wet-lab approaches, where only low-frequency immunization started at an early disease stage in the NOD mouse resulted in significant protection from diabetes by inducing IL-10 and Treg. CONCLUSIONS Here, the advantage of applying computer modeling in optimizing the therapeutic efficacy of nasal insulin immunotherapy was confirmed. In silico modeling was able to streamline the experimental design and to identify the particular time frame at which biomarkers associated with protection in live NODs were induced. These results support the development and application of humanized platforms for the design of clinical trials (i.e., for the ongoing nasal insulin prevention studies).
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Affiliation(s)
- Georgia Fousteri
- Diabetes Center, La Jolla Institute for Allergy and Immunology, La Jolla, California
| | - Jason R. Chan
- Entelos, Foster City, California
- Corresponding authors: Jason R. Chan, , and Matthias von Herrath,
| | | | | | - Amy Dave
- Diabetes Center, La Jolla Institute for Allergy and Immunology, La Jolla, California
| | - Damien Bresson
- Diabetes Center, La Jolla Institute for Allergy and Immunology, La Jolla, California
| | - Michael Croft
- Diabetes Center, La Jolla Institute for Allergy and Immunology, La Jolla, California
| | - Matthias von Herrath
- Diabetes Center, La Jolla Institute for Allergy and Immunology, La Jolla, California
- Corresponding authors: Jason R. Chan, , and Matthias von Herrath,
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26
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Haller MJ, Atkinson MA, Schatz DA. Efforts to prevent and halt autoimmune beta cell destruction. Endocrinol Metab Clin North Am 2010; 39:527-39. [PMID: 20723818 PMCID: PMC2925042 DOI: 10.1016/j.ecl.2010.05.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Despite improvements in understanding of the natural history of type 1 diabetes (T1D), an intervention capable of consistently and safely preventing or reversing the disease has not been developed. The inability to cure this disorder is largely because of the complex pathophysiology of T1D, continued struggles to identify its precise etiologic triggers, and voids in understanding of the immunologic mechanisms that specifically target pancreatic beta cells. Rapidly improving technologies for managing T1D require critical discussions about equipoise, especially when considering interventions deemed high risk in terms of their safety. This article reviews the conceptual basis for prevention versus intervention trials in settings of T1D, past experiences of clinical trials studying these purposes, and controversial issues regarding disease interdiction, and seeks to provide a roadmap for future efforts to cure this disorder.
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Affiliation(s)
- Michael J Haller
- Division of Endocrinology, Department of Pediatrics, University of Florida, PO Box 100296, Gainesville, FL 32610, USA.
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27
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Autoantigen-specific regulatory T cells induced in patients with type 1 diabetes mellitus by insulin B-chain immunotherapy. J Autoimmun 2010; 34:408-15. [PMID: 19931408 DOI: 10.1016/j.jaut.2009.10.005] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2009] [Revised: 10/22/2009] [Accepted: 10/26/2009] [Indexed: 12/21/2022]
Abstract
There is a growing body of evidence to suggest that the autoimmunity observed in type 1 diabetes mellitus (T1DM) is the result of an imbalance between autoaggressive and regulatory cell subsets. Therapeutics that supplement or enhance the existing regulatory subset are therefore a much sought after goal in this indication. Here, we report the results of a double blind, placebo controlled, phase I clinical trial of a novel antigen-specific therapeutic in 12 subjects with recently diagnosed T1DM. Our primary objective was to test its safety. The study drug, human insulin B-chain in incomplete Freund's adjuvant (IFA) was administered as a single intramuscular injection, with subjects followed for 2 years. All subjects completed therapy and all follow-up visits. The therapy was generally safe and well-tolerated. Mixed meal stimulated C-peptide responses, measured every 6 months, showed no statistical differences between arms. All patients vaccinated with the autoantigen, but none who received placebo, developed robust insulin-specific humoral and T cell responses. Up to two years following the single injection, in peripheral blood from subjects in the experimental arm, but not the control arm, insulin B-chain-specific CD4+ T cells could be isolated and cloned that showed phenotypic and functional characteristics of regulatory T cells. The induction of a lasting, robust immune response generating autoantigen-specific regulatory T cells provides strong justification for further testing of this therapy in type 1 diabetes. (clinicaltrials.gov identifier NCT00057499).
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28
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Wicklow BA, Polychronakos C. Insulin auto-immunity: implications for the prevention of Type 1 diabetes mellitus. Expert Rev Clin Immunol 2010; 5:55-62. [PMID: 20476900 DOI: 10.1586/1744666x.5.1.55] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Mounting evidence suggests insulin is an important and potentially initiating antigen in the pathogenesis of Type 1 diabetes. High-affinity insulin antibodies are found early in disease development and appear to predict progression. Insulin is the only Type 1 diabetes auto-antigen with exclusive pancreatic expression and the only one whose gene maps to a major susceptibility locus. Preclinical studies in rodent models of immune-mediated diabetes show great promise for the possibility of preventing disease by peripheral tolerization. Translation of this evidence to clinical trials of oral, intranasal and parenteral insulin to invoke immune tolerance and prevent diabetes has not proven successful to date, but promising results in a small subset of highest-risk individuals have maintained enthusiasm for this promising prevention strategy. Currently, studies of oral and intranasal insulin are ongoing to determine the optimal dose, timing and target population for Type 1 diabetes prevention.
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Affiliation(s)
- Brandy A Wicklow
- Department of Pediatrics, Division of Pediatric Endocrinology, Montreal Children's Hospital, McGill University Health Center, 2300 rue Tupper, Montreal, QC H3H1P3, Canada
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29
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Bresson D, von Herrath M. Immunotherapy for the prevention and treatment of type 1 diabetes: optimizing the path from bench to bedside. Diabetes Care 2009; 32:1753-68. [PMID: 19794001 PMCID: PMC2752914 DOI: 10.2337/dc09-0373] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Damien Bresson
- From the Center for Type 1 Diabetes Research, La Jolla Institute for Allergy and Immunology, La Jolla, California
| | - Matthias von Herrath
- From the Center for Type 1 Diabetes Research, La Jolla Institute for Allergy and Immunology, La Jolla, California
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30
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von Herrath M, Nepom GT. Remodeling rodent models to mimic human type 1 diabetes. Eur J Immunol 2009; 39:2049-54. [DOI: 10.1002/eji.200939429] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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31
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An update on preventive and regenerative therapies in diabetes mellitus. Pharmacol Ther 2008; 121:317-31. [PMID: 19168093 DOI: 10.1016/j.pharmthera.2008.11.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2008] [Accepted: 11/26/2008] [Indexed: 01/09/2023]
Abstract
Type 1A (immune-mediated) and type 2 diabetes mellitus are two of the most common severe chronic illnesses, affecting over 230 million people worldwide with an estimated global prevalence of 5.1%. Although type 1 and type 2 diabetes differ greatly in modes of pathogenesis, these illnesses share a common pathology and consequences characterized by loss of functional beta-cell mass and subsequent dysregulation of carbohydrate and lipid metabolism. Since therapy for diabetes and the associated complications poses enormous public health and economic burdens, novel preventive and regenerative therapies have emerged in the past decade with the aim to preserve beta-cell mass and delay the onset of diabetes. The goal of this review is to provide a comprehensive overview of current efforts in the fight against diabetes, and attempts to document all strategies that have emerged in clinical studies within the past 25 years. First, strategies to identify individuals at risk, ranging from whole-genome scans to autoantibody screening, will be discussed. Second, novel approaches to prevent or delay the onset of disease will be covered. Particular focus is given on emerging strategies for individuals at risk for type 1 diabetes that target T-cell regulation and induction of tolerance, while new pharmaceutical concepts in combination with lifestyle interventions are discussed within the scope of type 2 diabetes prevention. Lastly, important efforts to halt disease progression with emphasis on beta-cell regeneration are presented.
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32
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Näntö-Salonen K, Kupila A, Simell S, Siljander H, Salonsaari T, Hekkala A, Korhonen S, Erkkola R, Sipilä JI, Haavisto L, Siltala M, Tuominen J, Hakalax J, Hyöty H, Ilonen J, Veijola R, Simell T, Knip M, Simell O. Nasal insulin to prevent type 1 diabetes in children with HLA genotypes and autoantibodies conferring increased risk of disease: a double-blind, randomised controlled trial. Lancet 2008; 372:1746-55. [PMID: 18814906 DOI: 10.1016/s0140-6736(08)61309-4] [Citation(s) in RCA: 262] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND In mouse models of diabetes, prophylactic administration of insulin reduced incidence of the disease. We investigated whether administration of nasal insulin decreased the incidence of type 1 diabetes, in children with HLA genotypes and autoantibodies increasing the risk of the disease. METHODS At three university hospitals in Turku, Oulu, and Tampere (Finland), we analysed cord blood samples of 116 720 consecutively born infants, and 3430 of their siblings, for the HLA-DQB1 susceptibility alleles for type 1 diabetes. 17 397 infants and 1613 siblings had increased genetic risk, of whom 11 225 and 1574, respectively, consented to screening of diabetes-associated autoantibodies at every 3-12 months. In a double-blind trial, we randomly assigned 224 infants and 40 siblings positive for two or more autoantibodies, in consecutive samples, to receive short-acting human insulin (1 unit/kg; n=115 and n=22) or placebo (n=109 and n=18) once a day intranasally. We used a restricted randomisation, stratified by site, with permuted blocks of size two. Primary endpoint was diagnosis of diabetes. Analysis was by intention to treat. The study was terminated early because insulin had no beneficial effect. This study is registered with ClinicalTrials.gov, number NCT00223613. FINDINGS Median duration of the intervention was 1.8 years (range 0-9.7). Diabetes was diagnosed in 49 index children randomised to receive insulin, and in 47 randomised to placebo (hazard ratio [HR] 1.14; 95% CI 0.73-1.77). 42 and 38 of these children, respectively, continued treatment until diagnosis, with yearly rates of diabetes onset of 16.8% (95% CI 11.7-21.9) and 15.3% (10.5-20.2). Seven siblings were diagnosed with diabetes in the insulin group, versus six in the placebo group (HR 1.93; 0.56-6.77). In all randomised children, diabetes was diagnosed in 56 in the insulin group, and 53 in the placebo group (HR 0.98; 0.67-1.43, p=0.91). INTERPRETATION In children with HLA-conferred susceptibility to diabetes, administration of nasal insulin, started soon after detection of autoantibodies, could not be shown to prevent or delay type 1 diabetes.
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Abstract
Type 1 diabetes mellitus results from the progressive and specific autoimmune destruction of insulin-secreting pancreatic B-cells, which develops over a period of years and continues after the initial clinical presentation. The ultimate goal of therapeutic intervention is prevention or reversal of the disease by the arrest of autoimmunity and by preservation/restoration of B-cell mass and function. Recent clinical trials of antigen-specific or non-specific immune therapies have proved that modulation of islet specific autoimmunity in humans and prevention of insulin secretion loss in the short term after the onset of disease is achievable. The identification of suitable candidates for therapy, appropriate dosage and timing, specificity of intervention and the side-effect profile are crucial for the success of any approach. Considering the complexity of the disease, it is likely that a rationally designed approach of combined immune-based therapies that target suppression of B-cell specific autoreactivity and maintenance of immune tolerance, coupled with islet regeneration or replacement of the destroyed B-cell mass, will prove to be most effective in causing remission/reversal of disease in a durable fashion.
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Affiliation(s)
- S Cernea
- Department of Immunobiology, Yale University, New Haven, CT, USA
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Wu HY. Induction of mucosal tolerance in SLE: a sniff or a sip away from ameliorating lupus? Clin Immunol 2008; 130:111-22. [PMID: 18938110 DOI: 10.1016/j.clim.2008.08.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Revised: 08/27/2008] [Accepted: 08/27/2008] [Indexed: 11/26/2022]
Abstract
Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by aberrant immune responses against intracellularly derived self antigens. Treatment for SLE relies on the use of aggressive immunosuppressants and steroids that are nonspecific and can cause serious adverse effects. The observation that a systemic immune tolerance to self antigens or generation of regulatory T cells may follow mucosal (nasal or oral) exposure to self proteins or monoclonal antibody against CD3 respectively suggests that induction of mucosal tolerance offers the basis of a side effect-free therapy that could re-establish the ability to distinguish self from non-self and restore peripheral tolerance in individuals susceptible to developing autoimmune diseases. Here I review studies on mucosal tolerance in autoimmune diseases and discuss the therapeutic potential of inducing tolerance for the treatment of SLE.
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Affiliation(s)
- Henry Yim Wu
- Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
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Haavisto LE, Sipilä JI. Acoustic rhinometry in children: some practical aspects and influence of age and body surface area on results. ACTA ACUST UNITED AC 2008; 22:416-9. [PMID: 18702909 DOI: 10.2500/ajr.2008.22.3197] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Since acoustic rhinometry was described there has been a lack of normal values for minimal cross-sectional area (MCA), especially for children. There has also been debate about factors influencing normal values. The purpose of this study was to find the normal values for children in a Finnish population and whether there is any correlation between age or body surface area (BSA) and MCA. METHODS We measured 74 children (age, 1-12 years) with an acoustic rhinometer. The values of MCA were compared with age and BSA determined from height and weight. RESULTS The mean of unilateral MCA was 0.225 cm2 (SD, 0.041). We found positive correlation between unilateral volume on the left side and age and between MCA from the right side and age or BSA as a constant predictor. As much as 28.4% of the measurements had to be rejected because of acoustic leakage between nostril and nosepiece. Only 6.8% had to be rejected because of a lack of cooperation. CONCLUSION It is possible to find normal values for children. Acoustic rhinometry is well tolerated among children. The method is rapid, reliable and noninvasive, and minimal cooperation is required. The measurements must be performed in a standard way, and some important causes of errors must be kept in mind.
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Affiliation(s)
- Lotta E Haavisto
- Department of Otorhinolaryngology, Turku University Central Hospital, Turku, Finland.
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36
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Reger MA, Watson GS, Green PS, Baker LD, Cholerton B, Fishel MA, Plymate SR, Cherrier MM, Schellenberg GD, Frey WH, Craft S. Intranasal insulin administration dose-dependently modulates verbal memory and plasma amyloid-beta in memory-impaired older adults. J Alzheimers Dis 2008; 13:323-31. [PMID: 18430999 DOI: 10.3233/jad-2008-13309] [Citation(s) in RCA: 390] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Intranasal insulin administration raises central nervous system (CNS) insulin levels in humans and acutely facilitates verbal memory in patients with Alzheimer's disease (AD), an effect that may differ by APOE genotype. The purpose of this study was to examine the cognitive dose response curves for intranasal insulin administration, and determine whether the effects of insulin differ between participants with (epsilon4+) and without (epsilon4-) the APOE- epsilon4 allele. On separate mornings, 33 memory-impaired adults with AD or amnestic mild cognitive impairment and 59 normal adults each underwent five intranasal treatment conditions consisting of insulin (10, 20, 40, or 60 IU) or placebo. Cognition was tested 15-minutes post-treatment, and blood was acquired at baseline and 45-minutes post-treatment. Plasma insulin and glucose levels were unaffected by treatment. Insulin administration facilitated recall on two measures of verbal memory in memory-impaired epsilon4- adults, with performance generally peaking at 20 IU. In contrast, memory-impaired epsilon4+ subjects demonstrated a relative decline in verbal memory. Insulin also differentially modulated plasma amyloid-beta for memory-impaired subjects and normal controls, effects that again differed by APOE genotype. These findings suggest that groups with different genetic risks for AD may show differential dose-response curves following intranasal insulin administration.
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Affiliation(s)
- Mark A Reger
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108, USA
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T-cell reactivity to insulin peptide A1-12 in children with recently diagnosed type 1 diabetes or multiple beta-cell autoantibodies. J Autoimmun 2008; 31:142-8. [PMID: 18565729 DOI: 10.1016/j.jaut.2008.04.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2008] [Revised: 04/14/2008] [Accepted: 04/24/2008] [Indexed: 11/20/2022]
Abstract
Insulin-specific immune responses appear early in preclinical type 1 diabetes (T1D), and bovine insulin in cow's milk-based infant formulas has been suggested to be of importance in induction of the primary response to insulin in humans. To characterize insulin-specific T-cell reactivity we studied T-cell responses to 10 insulin peptides derived from bovine (BI) and human insulin (HI) in 42 children with recently diagnosed T1D, 47 children with multiple autoantibodies and 111 autoantibody-negative control children with risk-associated HLA alleles. Proliferation responses detected in antigen-stimulated peripheral blood mononuclear cells did not differ between the three groups when the comparison was performed without considering HLA genotypes. However, significant differences were observed, when children with the high-risk genotype HLA (DRB1*03)-DQA1*05-DQB1*02/DRB1*0401-DQA1*03-DQB1*0302 were analyzed separately. The responses to the peptides including amino acids A1-12 derived from B1 and H1 were significantly higher in children with T1D (P=0.008, P=0.004, for B1 and H1, respectively) and in children with diabetes-associated autoantibodies (P=0.002 and P=0.001, respectively) than in control children. Positive responses (stimulation indices SI> or =3) were seen more frequently in T1D children than in controls (4/7 vs 2/19; P=0.03 and 4/7 vs 1/19; P=0.01 for B1 and H1, respectively). T-cell response to the insulin peptide A1-12 is enhanced in clinical and preclinical T1D associated with the high-risk HLA-genotype emphasizing the importance of this epitope.
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Sherr J, Sosenko J, Skyler JS, Herold KC. Prevention of type 1 diabetes: the time has come. ACTA ACUST UNITED AC 2008; 4:334-43. [PMID: 18446141 DOI: 10.1038/ncpendmet0832] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2008] [Accepted: 03/03/2008] [Indexed: 01/12/2023]
Abstract
Improved understanding of the pathogenesis of type 1 diabetes mellitus has completely changed our view of this disease in the past 25 years-from an acute, fulminant disease, to a chronic, autoimmune process. Information on genetic and serologic markers has increased our ability to identify individuals at risk. Prospectively gathered data indicate that, with a combination of immunologic and metabolic studies, children with a 6-year risk of disease higher than 90% can be identified due to an ongoing immune process. They differ from children with overt disease only in the time it will take for glucose levels to rise above a diagnostic threshold. Therapies to change the progression of beta-cell loss have been tested in patients with newly diagnosed type 1 diabetes. With improved predictive capabilities and agents that can have longer-lasting effects than those tested more than 10 years ago, new prevention studies are underway. These studies are large and costly but the risks posed by such interventions compare favorably with those of developing hyperglycemia and of future complications portended by the diagnosis of diabetes. In this Review we discuss risk-stratification techniques and how they are applied, other diagnostic criteria, and outcomes from diabetes-prevention trials.
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Affiliation(s)
- Jennifer Sherr
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT, USA
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Achenbach P, Barker J, Bonifacio E. Modulating the natural history of type 1 diabetes in children at high genetic risk by mucosal insulin immunization. Curr Diab Rep 2008; 8:87-93. [PMID: 18445349 DOI: 10.1007/s11892-008-0017-y] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Mucosal administration of insulin represents an attractive antigen-specific therapeutic approach to preventing type 1 diabetes. It can prevent autoimmune diabetes in animal models, but although it has been shown to be safe, it has not yet been proven effective in human studies. Efficacy may depend on the dose and route at which insulin is administered, the stage in type 1 diabetes pathogenesis at which treatment is initiated, and the study cohort that is treated. We have proposed Pre-POINT (Primary Oral/intranasal INsulin Trial), a dose-finding safety and immune efficacy pilot study for primary mucosal insulin therapy in islet autoantibody-negative children at high genetic risk for type 1 diabetes who naturally first develop autoimmunity to insulin. Pre-POINT aims to identify an optimal insulin dose and route of application (orally or intranasally) that is well tolerated and can induce an immune response to insulin for additional use in a phase II/III primary prevention trial in children at risk.
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Affiliation(s)
- Peter Achenbach
- Diabetes Research Institute, Koelner Platz 1, Munich 80804, Germany.
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Haller MJ, Gottlieb PA, Schatz DA. Type 1 diabetes intervention trials 2007: where are we and where are we going? Curr Opin Endocrinol Diabetes Obes 2007; 14:283-7. [PMID: 17940453 DOI: 10.1097/med.0b013e32825a673b] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Type 1 diabetes (T1D) is characterized by autoimmune-mediated destruction of pancreatic beta cells culminating in absolute insulin deficiency. Despite enhanced knowledge of the natural history of type 1 diabetes we have yet to develop an intervention to consistently and safely prevent or reverse type 1 diabetes. This review explores the lessons learned from recent type 1 diabetes interventional studies, sets out controversial issues and seeks to provide a roadmap for future interventions. RECENT FINDINGS The type 1 diabetes intervention studies of the 1980s demonstrated potential for preserving c-peptide, but were abandoned due to unacceptable side-effect profiles of the agents being used. Pilot studies of new immunosuppressive and immunomodulatory agents with improved side-effect profiles have recently demonstrated promise in preserving c-peptide in new-onset type 1 diabetes patients. Several of these agents, including insulin, anti-CD3, mycophenolate mofetil, daclizumab and anti-CD20, are currently being tested in multicenter intervention trials. SUMMARY The inability to cure type 1 diabetes underscores the complex pathophysiology of the disease, and our poor knowledge of the precise etiological triggers and immunological mechanisms which culminate in the disease. While ongoing efforts to test individual agents with potential to ameliorate diabetes are needed, combination therapies employing multiple safe agents are likely to be the future of type 1 diabetes intervention studies.
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Affiliation(s)
- Michael J Haller
- Department of Pediatrics, University of Florida, Gainesville, Florida 32610, USA.
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von Herrath M, Rottembourg D, Bresson D. Progress in the development of immune-based therapies for type 1 diabetes mellitus. BioDrugs 2007; 20:341-50. [PMID: 17176121 DOI: 10.2165/00063030-200620060-00004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Between ten and twenty million people worldwide have type 1 diabetes mellitus (T1DM), which has previously been called juvenile diabetes, childhood diabetes, and insulin-dependent diabetes mellitus. T1DM is undoubtedly a multifactorial disease affecting predisposed individuals with genetic susceptibilities; it is also associated with environmental factors leading to unbalanced immune responses. This chronic disorder is caused by auto-aggressive T lymphocytes entering the pancreatic islets of Langerhans where they destroy the insulin-producing beta-cells. A wide variety of immuno-interventions cure T1DM effectively in different animal models when given early in disease development. However, few of these interventions are efficacious in humans at a later stage of the disease. Indeed, only three immunotherapeutic compounds have demonstrated both safety and efficacy in phase II/III clinical trials. Although much time and resources have been spent on generating potent immune therapies, none of the patients enrolled in these trials have achieved normoglycemia in the absence of insulin injections. Many reasons can account for such a disappointing conclusion. Firstly, the dynamics of disease pathogenesis differs significantly from patient to patient, which directly impacts the therapeutic efficacy. Also, at trial entry, the percentage of remaining pancreatic beta-cells in T1DM patients often reflects the odds of responding positively to treatment. Based on the knowledge we have gained from preclinical studies and clinical trials, several steps have been made in the development of safer and more efficient immune-based therapies. There are, however, a number of concerns that should be addressed in order to improve future therapeutic strategies.
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Affiliation(s)
- Matthias von Herrath
- Department of Developmental Immunology, La Jolla Institute for Allergy and Immunology, La Jolla, California 92037, USA
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Staeva-Vieira T, Peakman M, von Herrath M. Translational mini-review series on type 1 diabetes: Immune-based therapeutic approaches for type 1 diabetes. Clin Exp Immunol 2007; 148:17-31. [PMID: 17349010 PMCID: PMC1868847 DOI: 10.1111/j.1365-2249.2007.03328.x] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Type 1 diabetes (T1D) is often considered the prototype organ-specific autoimmune disease in clinical immunology circles. The key disease features - precise destruction of a single endocrine cell type occurring on a distinct genetic and autoimmune background - have been unravelled in recent years to such an extent that there is a growing expectation that the disease should be curable. T1D is something of an orphan disease, currently managed by endocrinologists yet dependent upon the wit of immunologists, both basic and clinical, to find the best approaches to prevention and cure. Type 1 diabetes thus represents one of the most active arenas for translational research, as novel immune-based interventions find their way to the clinic. The first serious attempt at immune-based treatment for T1D was in 1984, the first at prevention in 1993; current and planned trials will take us into the next decade before reporting their results. This paper represents the first attempt at a comprehensive review of this quarter century of endeavour, documenting all the strategies that have emerged into clinical studies. Importantly, the intense clinical activity has established robust infrastructures for future T1D trials and frameworks for their design. The evident success of the monoclonal anti-CD3 antibody trials in established T1D demonstrate that modulation of islet autoimmunity in humans after the onset of overt disease can be achieved, and give some reason to be cautiously optimistic for the ability of these and other agents, alone and in combination, to provide an effective immunotherapy for the disease.
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Affiliation(s)
- T Staeva-Vieira
- Research Department, Juvenile Diabetes Research Foundation International, New York, NY 10005-4001, USA.
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Abstract
The human gut offers more than 200 m2 of mucosal surface, where direct interactions between the immune system and foreign antigens take place to eliminate pathogens or induce immune tolerance toward food antigens or normal gut flora. Therefore, mucosally administered antigens can induce tolerance under certain circumstances. In autoimmune diabetes, mucosal vaccination with autoantigens elicits some efficacy in restoring tolerance in mice, but it never succeeded in humans. Furthermore, in some instances autoimmunity can be precipitated upon oral or intranasal autoantigen administration. Therefore, it is difficult to predict the effect of mucosal vaccination on autoimmunity and much effort should be put into establishing better assays to reduce the risk for possible adverse events in humans and enable a rapid and smooth translation.
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Affiliation(s)
- Georgia Fousteri
- La Jolla Institute for Allergy and Immunology, Department of Developmental Immunology 3, 9420 Athena Circle, La Jolla, CA 92037, USA.
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Bresson D, von Herrath M. Moving towards efficient therapies in type 1 diabetes: to combine or not to combine? Autoimmun Rev 2007; 6:315-22. [PMID: 17412305 PMCID: PMC1896372 DOI: 10.1016/j.autrev.2006.09.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2006] [Revised: 09/13/2006] [Accepted: 09/20/2006] [Indexed: 12/22/2022]
Abstract
Every year, thirty thousand people worldwide are diagnosed with type 1 diabetes mellitus (T1DM). T1DM, also called autoimmune diabetes, is a multifactorial disease affecting predisposed individuals and involving genetic susceptibilities, environmental triggers, as well as unbalanced immune responses. Auto-reactive T cells, produced during the pathogenesis, play an important role by specifically destroying the pancreatic insulin-producing beta-cells in the islets of Langerhans. Numerous therapeutic interventions have been tested, mostly in animal models, but also in humans. To date, only three phase II/III clinical trials have demonstrated safety and efficacy: anti-CD3 antibody, DiaPep277, and GAD65 (in patients with latent autoimmune diabetes in adults). Unfortunately, a significant number of patients did not respond positively and remained insulin-dependent after completion of therapy. Several reasons account for this. Firstly, the severity of the disease as well as the auto-aggressive T cell repertoire vary from patient to patient leading to a broad range of therapeutic efficacies, and secondly at the time of the treatment the number of remaining beta-cells will directly impact the level of insulin production post-treatment. In this review, we will provide some clues to enhance efficacy of future immuno-interventions in patients with T1DM. We suggest that combination therapies might be the best approach.
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Affiliation(s)
- D Bresson
- La Jolla Institute for Allergy and Immunology, Department of Developmental Immunology, San Diego, CA 92121, USA
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45
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Mäkelä M, Vaarala O, Hermann R, Salminen K, Vahlberg T, Veijola R, Hyöty H, Knip M, Simell O, Ilonen J. Enteral virus infections in early childhood and an enhanced type 1 diabetes-associated antibody response to dietary insulin. J Autoimmun 2006; 27:54-61. [PMID: 16757149 DOI: 10.1016/j.jaut.2006.04.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2006] [Revised: 04/19/2006] [Accepted: 04/24/2006] [Indexed: 11/16/2022]
Abstract
Enteral virus infections may trigger the development of beta-cell-specific autoimmunity by interacting with the gut-associated lymphoid system. We analyzed the effect of three different virus infections on immunization to dietary insulin in children carrying increased genetic risk for type 1 diabetes. Forty-six of 238 children developed multiple diabetes-associated autoantibodies and 31 clinical diabetes (median follow-up time 75 months). Insulin-binding antibodies were measured with EIA method (median follow-up time 24 months). Antibodies to enteroviruses, rotavirus and adenovirus were measured with EIA in samples drawn at birth and the ages of 3 and 6 months. Nineteen enterovirus, 14 rotavirus and 8 adenovirus infections were diagnosed. At the ages of 6, 12, and 18 months, the concentrations of insulin-binding antibodies were higher in children with postnatal entero-, rota- and/or adenovirus infections than in children without these infections. Children who subsequently developed ICA or IA-2 antibodies or clinical type 1 diabetes had higher concentrations of insulin-binding antibodies than children who remained autoantibody negative. Our data suggest that enteral virus infections can enhance immune response to insulin, induced primarily by bovine insulin in cow's milk. An enhanced antibody response to dietary insulin preceded the development of beta-cell specific autoimmunity and type 1 diabetes.
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Affiliation(s)
- Miia Mäkelä
- Immunogenetics Laboratory, University of Turku, Medicity, Biocity 4. krs, Tykistökatu 6 A, 20520 Turku, Finland.
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McIntyre RS, Soczynska JK, Lewis GF, MacQueen GM, Konarski JZ, Kennedy SH. Managing psychiatric disorders with antidiabetic agents: translational research and treatment opportunities. Expert Opin Pharmacother 2006; 7:1305-21. [PMID: 16805717 DOI: 10.1517/14656566.7.10.1305] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The objective of this paper is to synthesise extant studies describing the neurotherapeutic effects of antidiabetic agents in neuropsychiatric disorders. The authors conducted a MedLine search of all English-language articles published between 1966 and March 2006. The search terms were the nonproprietary names of established and putative antidiabetic agents (e.g., insulin, insulin secretagogues and sensitisers) cross-referenced with the individual names of Diagnostic and Statistical Manual of Mental Disorders (DSM)-III-R/IV/-TR-defined mood, psychotic, anxiety and dementing disorders. The search was augmented with a manual review of article reference lists. Contemporary models of disease pathophysiology in major depressive disorder, bipolar disorder and several dementing disorders (e.g., Alzheimer's disease) emphasise alterations in cellular plasticity and cytoarchitecture, with associated regional abnormalities in neuronal and glial density and morphology. Antidiabetic treatments (e.g., thiazolidinediones) may be capable of attenuating this pathological process via disparate mechanisms (e.g., neuroprotective, neurotrophic, anti-inflammatory). Enhanced insulin signalling with antidiabetic treatments may preserve and/or augment cognitive function in several neuropsychiatric disorders. Antidiabetic treatments, which maintain euglycaemia, hold promise as potent and clinically significant therapeutic interventions for several neuropsychiatric disorders.
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Affiliation(s)
- Roger S McIntyre
- Mood Disorders Psychopharmacology Unit, University Health Network, 399 Bathurst Street-Toronto, ON, M5T 2S8, Canada.
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Reger MA, Watson GS, Frey WH, Baker LD, Cholerton B, Keeling ML, Belongia DA, Fishel MA, Plymate SR, Schellenberg GD, Cherrier MM, Craft S. Effects of intranasal insulin on cognition in memory-impaired older adults: Modulation by APOE genotype. Neurobiol Aging 2006; 27:451-8. [PMID: 15964100 DOI: 10.1016/j.neurobiolaging.2005.03.016] [Citation(s) in RCA: 472] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2004] [Revised: 02/22/2005] [Accepted: 03/03/2005] [Indexed: 12/11/2022]
Abstract
Raising insulin acutely in the periphery and in brain improves verbal memory. Intranasal insulin administration, which raises insulin acutely in the CNS without raising plasma insulin levels, provides an opportunity to determine whether these effects are mediated by central insulin or peripheral processes. Based on prior research with intravenous insulin, we predicted that the treatment response would differ between subjects with (epsilon4+) and without (epsilon4-) the APOE-epsilon4 allele. On separate mornings, 26 memory-impaired subjects (13 with early Alzheimer's disease and 13 with amnestic mild cognitive impairment) and 35 normal controls each underwent three intranasal treatment conditions consisting of saline (placebo) or insulin (20 or 40 IU). Cognition was tested 15 min post-treatment, and blood was acquired at baseline and 45 min after treatment. Intranasal insulin treatment did not change plasma insulin or glucose levels. Insulin treatment facilitated recall on two measures of verbal memory in memory-impaired epsilon4- adults. These effects were stronger for memory-impaired epsilon4- subjects than for memory-impaired epsilon4+ subjects and normal adults. Unexpectedly, memory-impaired epsilon4+ subjects showed poorer recall following insulin administration on one test of memory. These findings suggest that intranasal insulin administration may have therapeutic benefit without the risk of peripheral hypoglycemia and provide further evidence for apolipoprotein E (APOE) related differences in insulin metabolism.
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Affiliation(s)
- M A Reger
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Puget Sound Health Care System, 1660 S, Columbian Way, S182-GRECC, Seattle, WA 98108, USA
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48
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Abstract
Type 1A diabetes is a chronic autoimmune disease usually preceded by a long prodrome during which autoantibodies to islet autoantigens are present. These antibodies are directed to a variety of antigens, but the best characterized are glutamic acid decarboxylase-65, insulinoma-associated antigen-2, and insulin. We hypothesize that the natural history of type 1A diabetes can be represented by several stages, starting from genetic susceptibility and ending in complete beta-cell destruction and overt diabetes. Type 1A diabetes probably results from a balance between genetic susceptibility and environmental influences. In both humans and animal models, the major determinants of the disease are genes within the major histocompatibility complex. The next best-characterized susceptibility locus is the insulin gene, the variable nucleotide tandem repeat locus. This gene affects the expression of insulin in the thymus and thus may play a role in the modulation of tolerance to this molecule. In a subset of genetically susceptible individuals, the activation of autoimmunity may be triggered by environmental factors such as viruses and/or diet. However, no conclusive association has been established between type 1A diabetes and specific environmental triggers. In this review, we provide evidence that insulin has a fundamental role in anti-islet autoimmunity.
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Affiliation(s)
- Roberto Gianani
- The Barbara Davis Center for Childhood Diabetes, University of Colorado Health Sciences Center, Denver, CO, USA.
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49
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Harrison LC, Honeyman MC, Steele CE, Stone NL, Sarugeri E, Bonifacio E, Couper JJ, Colman PG. Pancreatic beta-cell function and immune responses to insulin after administration of intranasal insulin to humans at risk for type 1 diabetes. Diabetes Care 2004; 27:2348-55. [PMID: 15451899 DOI: 10.2337/diacare.27.10.2348] [Citation(s) in RCA: 152] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Mucosal administration of insulin retards development of autoimmune diabetes in the nonobese diabetic mouse model. We conducted a double-blind crossover study in humans at risk for type 1 diabetes to determine if intranasal insulin was safe, in particular did not accelerate beta-cell destruction, and could induce immune effects consistent with mucosal tolerance. RESEARCH DESIGN AND METHODS A total of 38 individuals, median age 10.8 years, with antibodies to one or more pancreatic islet antigens (insulin, GAD65, or tyrosine phosphatase-like insulinoma antigen 2) were randomized to treatment with intranasal insulin (1.6 mg) or a carrier solution, daily for 10 days and then 2 days a week for 6 months, before crossover. The primary outcome was beta-cell function measured as first-phase insulin response (FPIR) to intravenous glucose at 0, 6, and 12 months and then yearly; the secondary outcome was immunity to islet antigens, measured monthly for 12 months. RESULTS No local or systemic adverse effects were observed. Diabetes developed in 12 participants with negligible beta-cell function at entry after a median of 1.1 year. Of the remaining 26, the majority had antibodies to two or three islet antigens and FPIR greater than the first percentile at entry, as well as beta-cell function that generally remained stable over a median follow-up of 3.0 years. Intranasal insulin was associated with an increase in antibody and a decrease in T-cell responses to insulin. CONCLUSIONS Results from this pilot study suggest that intranasal insulin does not accelerate loss of beta-cell function in individuals at risk for type 1 diabetes and induces immune changes consistent with mucosal tolerance to insulin. These findings justify a formal trial to determine if intranasal insulin is immunotherapeutic and retards progression to clinical diabetes.
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Affiliation(s)
- Leonard C Harrison
- Autoimmunity and Transplantation Division, The WalterEliza Hall Institute of Medical Research, 1G Royal Parade, Parkville 3050, Victoria, Australia.
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