1
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Derkach KV, Sorokoumov VN, Bakhtyukov AA, Bondareva VM, Shpakov AO. Insulin and Leptin Levels in Blood and Brain Structures of Rats with Diet-Induced Obesity and the Effect of Various Drugs on Them. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s0022093022060187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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2
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Kim HK, Song J. Hypothyroidism and Diabetes-Related Dementia: Focused on Neuronal Dysfunction, Insulin Resistance, and Dyslipidemia. Int J Mol Sci 2022; 23:ijms23062982. [PMID: 35328405 PMCID: PMC8952212 DOI: 10.3390/ijms23062982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/06/2022] [Accepted: 03/07/2022] [Indexed: 01/27/2023] Open
Abstract
The incidence of dementia is steadily increasing worldwide. The risk factors for dementia are diverse, and include genetic background, environmental factors, sex differences, and vascular abnormalities. Among the subtypes of dementia, diabetes-related dementia is emerging as a complex type of dementia related to metabolic imbalance, due to the increase in the number of patients with metabolic syndrome and dementia worldwide. Thyroid hormones are considered metabolic regulatory hormones and affect various diseases, such as liver failure, obesity, and dementia. Thyroid dysregulation affects various cellular mechanisms and is linked to multiple disease pathologies. In particular, hypothyroidism is considered a critical cause for various neurological problems-such as metabolic disease, depressive symptoms, and dementia-in the central nervous system. Recent studies have demonstrated the relationship between hypothyroidism and brain insulin resistance and dyslipidemia, leading to diabetes-related dementia. Therefore, we reviewed the relationship between hypothyroidism and diabetes-related dementia, with a focus on major features of diabetes-related dementia such as insulin resistance, neuronal dysfunction, and dyslipidemia.
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Affiliation(s)
- Hee Kyung Kim
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Chonnam National University Medical School, 264 Seoyangro, Hwasun 58128, Korea;
| | - Juhyun Song
- Department of Anatomy, Chonnam National University Medical School, Hwasun 58128, Korea
- BioMedical Sciences Graduate Program (BMSGP), Chonnam National University, 264 Seoyangro, Hwasun 58128, Korea
- Correspondence: ; Tel.: +82-61-379-2706; Fax: +82-61-375-5834
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3
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Chung JY, Kim OY, Song J. Role of ketone bodies in diabetes-induced dementia: sirtuins, insulin resistance, synaptic plasticity, mitochondrial dysfunction, and neurotransmitter. Nutr Rev 2021; 80:774-785. [PMID: 34957519 PMCID: PMC8907488 DOI: 10.1093/nutrit/nuab118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Abstract
Patients with type 2 diabetes can have several neuropathologies, such as memory deficits. Recent studies have focused on the association between metabolic imbalance and neuropathological problems, and the associated molecular pathology. Diabetes triggers neuroinflammation, impaired synaptic plasticity, mitochondrial dysfunction, and insulin resistance in the brain. Glucose is a main energy substrate for neurons, but under certain conditions, such as fasting and starvation, ketone bodies can be used as an energy fuel for these cells. Recent evidence has shed new light on the role of ketone bodies in regulating several anti-inflammation cellular pathways and improving glucose metabolism, insulin action, and synaptic plasticity, thereby being neuroprotective. However, very high amount of ketone bodies can be toxic for the brain, such as in ketoacidosis, a dangerous complication that may occur in type 1 diabetes mellitus or alcoholism. Recent findings regarding the relationship between ketone bodies and neuropathogenesis in dementia are reviewed in this article. They suggest that the adequately low amount of ketone bodies can be a potential energy source for the treatment of diabetes-induced dementia neuropathology, considering the multifaceted effects of the ketone bodies in the central nervous system. This review can provide useful information for establishing the therapeutic guidelines of a ketogenic diet for diabetes-induced dementia.
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Affiliation(s)
- Ji Yeon Chung
- Department of Neurology, Chosun University Medical School, Gwangju, Republic of Korea
| | - Oh Yoen Kim
- Department of Food Science and Nutrition and the Department of Health Sciences, Dong-A University, Busan, Republic of Korea
| | - Juhyun Song
- Department of Anatomy, Chonnam National University Medical School, Hwasun, Jeollanam-do, Republic of Korea
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4
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Chandrashekar C, Hossain MA, Wade JD. Chemical Glycosylation and Its Application to Glucose Homeostasis-Regulating Peptides. Front Chem 2021; 9:650025. [PMID: 33912539 PMCID: PMC8072350 DOI: 10.3389/fchem.2021.650025] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 03/22/2021] [Indexed: 11/13/2022] Open
Abstract
Peptides and proteins are attractive targets for therapeutic drug development due to their exquisite target specificity and low toxicity profiles. However, their complex structures give rise to several challenges including solubility, stability, aggregation, low bioavailability, and poor pharmacokinetics. Numerous chemical strategies to address these have been developed including the introduction of several natural and non-natural modifications such as glycosylation, lipidation, cyclization and PEGylation. Glycosylation is considered to be one of the most useful modifications as it is known to contribute to increasing the stability, to improve solubility, and increase the circulating half-lifves of these biomolecules. However, cellular glycosylation is a highly complex process that generally results in heterogenous glycan structures which confounds quality control and chemical and biological assays. For this reason, much effort has been expended on the development of chemical methods, including by solid phase peptide synthesis or chemoenzymatic processes, to enable the acquisition of homogenous glycopeptides to greatly expand possibilities in drug development. In this mini-review, we highlight the importance of such chemical glycosylation methods for improving the biophysical properties of naturally non-glycosylated peptides as applied to the therapeutically essential insulin and related peptides that are used in the treatment of diabetes.
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Affiliation(s)
- Chaitra Chandrashekar
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia
| | - Mohammed Akhter Hossain
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia
| | - John D Wade
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia.,School of Chemistry, University of Melbourne, Melbourne, VIC, Australia
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5
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Ashraf GM, Ebada MA, Suhail M, Ali A, Uddin MS, Bilgrami AL, Perveen A, Husain A, Tarique M, Hafeez A, Alexiou A, Ahmad A, Kumar R, Banu N, Najda A, Sayed AA, Albadrani GM, Abdel-Daim MM, Peluso I, Barreto GE. Dissecting Sex-Related Cognition between Alzheimer's Disease and Diabetes: From Molecular Mechanisms to Potential Therapeutic Strategies. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:4572471. [PMID: 33747345 PMCID: PMC7960032 DOI: 10.1155/2021/4572471] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 01/31/2021] [Accepted: 02/11/2021] [Indexed: 12/16/2022]
Abstract
The brain is a sexually dimorphic organ that implies different functions and structures depending on sex. Current pharmacological approaches against different neurological diseases act distinctly in male and female brains. In all neurodegenerative diseases, including Alzheimer's disease (AD), sex-related outcomes regarding pathogenesis, prevalence, and response to treatments indicate that sex differences are important for precise diagnosis and therapeutic strategy. Pathogenesis of AD includes vascular dementia, and in most cases, this is accompanied by metabolic complications with similar features as those assembled in diabetes. This review discusses how AD-associated dementia and diabetes affect cognition in relation to sex difference, as both diseases share similar pathological mechanisms. We highlight potential protective strategies to mitigate amyloid-beta (Aβ) pathogenesis, emphasizing how these drugs act in the male and female brains.
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Affiliation(s)
- Ghulam Md Ashraf
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
- Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Mahmoud Ahmed Ebada
- Faculty of Medicine, Zagazig University, Zagazig, El-Sharkia, Egypt
- National Hepatology and Tropical Medicine Research Institute, Cairo, Egypt
| | - Mohd Suhail
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
- Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Ashraf Ali
- Department of Sciences of Agriculture, Food, Natural Resources, and Engineering (DAFNE), University of Foggia, Via Napoli 25, 71122 Foggia, Italy
| | - Md. Sahab Uddin
- Department of Pharmacy, Southeast University, Dhaka, Bangladesh
- Pharmakon Neuroscience Research Network, Dhaka, Bangladesh
| | - Anwar L. Bilgrami
- Department of Entomology, Rutgers University, New Brunswick, NJ 018901, USA
- Deanship of Scientific Research, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Asma Perveen
- Glocal School of Life Sciences, Glocal University, Saharanpur, India
| | - Amjad Husain
- Glocal School of Life Sciences, Glocal University, Saharanpur, India
- Centre for Science and Society, IISER Bhopal, India
- Innovation and Incubation Centre for Entrepreneurship, IISER Bhopal, India
| | - Mohd Tarique
- Department of Child Health, University of Missouri, Columbia, MO 65201, USA
| | - Abdul Hafeez
- Glocal School of Pharmacy, Glocal University, Saharanpur, India
| | - Athanasios Alexiou
- Novel Global Community Educational Foundation, New South Wales, Australia
- AFNP Med Austria, Wien, Austria
| | - Ausaf Ahmad
- Amity Institute of Biotechnology, Amity University Uttar Pradesh Lucknow Campus, Uttar Pradesh, India
| | - Rajnish Kumar
- Amity Institute of Biotechnology, Amity University Uttar Pradesh Lucknow Campus, Uttar Pradesh, India
| | - Naheed Banu
- Department of Physical Therapy, College of Medical Rehabilitation, Qassim University, Buraidah, Qassim, Saudi Arabia
| | - Agnieszka Najda
- Laboratory of Quality of Vegetables and Medicinal Plants, Department of Vegetable Crops and Medicinal Plants, University of Life Sciences in Lublin, 15 Akademicka Street, 20-950 Lublin, Poland
| | - Amany A. Sayed
- Zoology Department, Faculty of Science, Cairo University, Giza 12613, Egypt
| | - Ghadeer M. Albadrani
- Department of Biology, College of Science, Princess Nourah bint Abdulrahman University, Riyadh 11474, Saudi Arabia
| | - Mohamed M. Abdel-Daim
- Pharmacology Department, Faculty of Veterinary Medicine, Suez Canal University, Ismailia 41522, Egypt
| | - Ilaria Peluso
- Research Centre for Food and Nutrition, Council for Agricultural Research and Economics (CREA-AN), 00142 Rome, Italy
| | - George E. Barreto
- Department of Biological Sciences, University of Limerick, Limerick, Ireland
- Health Research Institute, University of Limerick, Limerick, Ireland
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6
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Maikawa CL, Smith AAA, Zou L, Roth GA, Gale EC, Stapleton LM, Baker SW, Mann JL, Yu AC, Correa S, Grosskopf AK, Liong CS, Meis CM, Chan D, Troxell M, Maahs DM, Buckingham BA, Webber MJ, Appel EA. A co-formulation of supramolecularly stabilized insulin and pramlintide enhances mealtime glucagon suppression in diabetic pigs. Nat Biomed Eng 2020; 4:507-517. [PMID: 32393892 PMCID: PMC7274092 DOI: 10.1038/s41551-020-0555-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 04/03/2020] [Indexed: 02/06/2023]
Abstract
Treatment of patients with diabetes with insulin and pramlintide (an amylin analogue) is more effective than treatment with insulin only. However, because mixtures of insulin and pramlintide are unstable and have to be injected separately, amylin analogues are only used by 1.5% of people with diabetes needing rapid-acting insulin. Here, we show that the supramolecular modification of insulin and pramlintide with cucurbit[7]uril-conjugated polyethylene glycol improves the pharmacokinetics of the dual-hormone therapy and enhances postprandial glucagon suppression in diabetic pigs. The co-formulation is stable for over 100 h at 37 °C under continuous agitation, whereas commercial formulations of insulin analogues aggregate after 10 h under similar conditions. In diabetic rats, the administration of the stabilized co-formulation increased the area-of-overlap ratio of the pharmacokinetic curves of pramlintide and insulin from 0.4 ± 0.2 to 0.7 ± 0.1 (mean ± s.d.) for the separate administration of the hormones. The co-administration of supramolecularly stabilized insulin and pramlintide better mimics the endogenous kinetics of co-secreted insulin and amylin, and holds promise as a dual-hormone replacement therapy.
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Affiliation(s)
- Caitlin L Maikawa
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Anton A A Smith
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA
- Department of Science and Technology, Aarhus University, Aarhus, Denmark
| | - Lei Zou
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, IN, USA
| | - Gillie A Roth
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Emily C Gale
- Department of Biochemistry, Stanford University, Stanford, CA, USA
| | | | - Sam W Baker
- Department of Comparative Medicine, Stanford University, Stanford, CA, USA
| | - Joseph L Mann
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA
| | - Anthony C Yu
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA
| | - Santiago Correa
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA
| | | | - Celine S Liong
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Catherine M Meis
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA
| | - Doreen Chan
- Department of Chemistry, Stanford University, Stanford, CA, USA
| | - Megan Troxell
- Department of Pathology, Stanford University, Stanford, CA, USA
| | - David M Maahs
- Department of Pediatrics (Endocrinology), Stanford University, Stanford, CA, USA
- Diabetes Research Center, Stanford University, Stanford, CA, USA
| | - Bruce A Buckingham
- Department of Pediatrics (Endocrinology), Stanford University, Stanford, CA, USA
- Diabetes Research Center, Stanford University, Stanford, CA, USA
| | - Matthew J Webber
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, IN, USA
| | - Eric A Appel
- Department of Bioengineering, Stanford University, Stanford, CA, USA.
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA.
- Department of Pediatrics (Endocrinology), Stanford University, Stanford, CA, USA.
- Diabetes Research Center, Stanford University, Stanford, CA, USA.
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7
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Bharadwaj P, Wijesekara N, Liyanapathirana M, Newsholme P, Ittner L, Fraser P, Verdile G. The Link between Type 2 Diabetes and Neurodegeneration: Roles for Amyloid-β, Amylin, and Tau Proteins. J Alzheimers Dis 2018; 59:421-432. [PMID: 28269785 DOI: 10.3233/jad-161192] [Citation(s) in RCA: 133] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A wealth of evidence indicates a strong link between type 2 diabetes (T2D) and neurodegenerative diseases such as Alzheimer's disease (AD). Although the precise mechanism remains unclear, T2D can exacerbate neurodegenerative processes. Brain atrophy, reduced cerebral glucose metabolism, and central nervous system insulin resistance are features of both AD and T2D. The T2D phenotype (glucose dyshomeostasis, insulin resistance, impaired insulin signaling) also promotes AD pathology, namely accumulation of amyloid-β (Aβ) and hyperphosphorylated tau and can induce other aspects of neuronal degeneration including inflammatory and oxidative processes. Aβ and hyperphosphorylated tau may also have roles in pancreatic β-cell dysfunction and in reducing insulin sensitivity and glucose uptake by peripheral tissues such as liver, skeletal muscle, and adipose tissue. This suggests a role for these AD-related proteins in promoting T2D. The accumulation of the islet amyloid polypeptide (IAPP, or amylin) within islet β-cells is a major pathological feature of the pancreas in patients with chronic T2D. Co-secreted with insulin, amylin accumulates over time and contributes to β-cell toxicity, ultimately leading to reduced insulin secretion and onset of overt (insulin dependent) diabetes. Recent evidence also suggests that this protein accumulates in the brain of AD patients and may interact with Aβ to exacerbate the neurodegenerative process. In this review, we highlight evidence indicating T2D in promoting Aβ and tau mediated neurodegeneration and the potential contributions of Aβ and tau in promoting a diabetic phenotype that could further exacerbate neurodegeneration. We also discuss underlying mechanisms by which amylin can contribute to the neurodegenerative processes.
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Affiliation(s)
- Prashant Bharadwaj
- School of Biomedical Sciences, Faculty of Health Sciences, Curtin Health Innovation Research Institute, Curtin University, WA, Australia.,Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, WA, Australia
| | - Nadeeja Wijesekara
- Tanz Centre for Research in Neurodegenerative Diseases, Krembil Discovery Tower, and Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Milindu Liyanapathirana
- School of Biomedical Sciences, Faculty of Health Sciences, Curtin Health Innovation Research Institute, Curtin University, WA, Australia
| | - Philip Newsholme
- School of Biomedical Sciences, Faculty of Health Sciences, Curtin Health Innovation Research Institute, Curtin University, WA, Australia
| | - Lars Ittner
- School of Medical Sciences, University of NSW, Kensington, NSW, Australia
| | - Paul Fraser
- Tanz Centre for Research in Neurodegenerative Diseases, Krembil Discovery Tower, and Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - Giuseppe Verdile
- School of Biomedical Sciences, Faculty of Health Sciences, Curtin Health Innovation Research Institute, Curtin University, WA, Australia.,Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, WA, Australia.,School of Psychiatry and Clinical Neurosciences, University of Western Australia, Crawley, Australia
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8
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Sukhov IB, Derkach KV, Chistyakova OV, Bondareva VM, Shpakov AO. The effect of prolonged intranasal administration of serotonin on the activity of hypothalamic signaling systems in male rats with neonatal diabetes. ACTA ACUST UNITED AC 2016. [DOI: 10.1134/s1990519x1604012x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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9
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Yule LR, Bower RL, Kaur H, Kowalczyk R, Hay DL, Brimble MA. Synthesis and amylin receptor activity of glycomimetics of pramlintide using click chemistry. Org Biomol Chem 2016; 14:5238-45. [PMID: 27139251 DOI: 10.1039/c6ob00850j] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Pramlintide (Symlin®), a synthetic analogue of the neuroendocrine hormone amylin, is devoid of the tendency to form cytotoxic amyloid fibrils and is currently used in patients with type I and type II diabetes mellitus as an adjunctive therapy with insulin or insulin analogues. As part of an on-going search for a pramlintide analogue with improved pharmacokinetic properties, we herein report the synthesis of mono- and di-glycosylated analogues of pramlintide and their activity at the AMY1(a) receptor. Introduction of N-glycosylated amino acids into the pramlintide sequence afforded the native N-linked glycomimetics whilst use of Cu(i)-catalysed azide-alkyne 1,3-dipolar cycloaddition (click) chemistry delivered 1,2,3-triazole linked glycomimetics. AMY1(a) receptor activity was retained by incorporation of single or multiple GlcNAc moieties at positions 21 and 35 of native pramlintide. Importantly, no difference in AMY1(a) activity was observed between native N-linked glycomimetics and 1,2,3-triazole linked glycomimetics demonstrating that the click variants can act as surrogates for the native N-glycosides in a biological setting.
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Affiliation(s)
- Lauren R Yule
- The School of Biological Sciences, University of Auckland, 3A Symonds St, Auckland 1010, New Zealand.
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10
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Krysiak R, Kowalcze K, Szkrobka W, Okopien B. The effect of metformin on prolactin levels in patients with drug-induced hyperprolactinemia. Eur J Intern Med 2016; 30:94-98. [PMID: 26858210 DOI: 10.1016/j.ejim.2016.01.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 12/29/2015] [Accepted: 01/19/2016] [Indexed: 01/11/2023]
Abstract
BACKGROUND In bromocriptine-treated hyperprolactinemic patients with impaired glucose tolerance, metformin was found to reduce plasma levels of prolactin. No previous study has investigated its impact on plasma prolactin in patients with drug-induced hyperprolactinemia. METHODS The study included 20 women with antipsychotic-induced hyperprolactinemia and 12 normoprolactinemic women, who, because of coexisting glucose metabolism abnormalities, were treated for 6months with metformin. Hyperprolactinemic patients with prediabetes received moderate doses of metformin (1.7g daily), while hyperprolactinemic and normoprolactinemic patients with type 2 diabetes were treated with high-dose metformin (2.55-3g daily). Fasting plasma glucose levels, the homeostatic model assessment 1 of insulin resistance ratio (HOMA1-IR), glycated hemoglobin, as well as plasma levels of prolactin, thyrotropin, adrenocorticotropic hormone and insulin-like growth factor-1 were assessed at baseline and after 6months of treatment. RESULTS Despite reducing plasma glucose, HOMA1-IR, and glycated hemoglobin in all treatment groups, metformin decreased prolactin levels only if given at high doses to patients with elevated prolactin levels. No changes in thyrotropin, adrenocorticotropic hormone, and insulin-like growth factor-1 were observed in any treatment groups. CONCLUSIONS The obtained results suggest that the effect of metformin on plasma prolactin depends on its dose and is observed only in patients with elevated levels of this hormone.
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Affiliation(s)
- Robert Krysiak
- Department of Internal Medicine and Clinical Pharmacology, Medical University of Silesia, Medyków 18, 40-752 Katowice, Poland.
| | - Karolina Kowalcze
- Department of Internal Medicine and Clinical Pharmacology, Medical University of Silesia, Medyków 18, 40-752 Katowice, Poland
| | - Witold Szkrobka
- Department of Internal Medicine and Clinical Pharmacology, Medical University of Silesia, Medyków 18, 40-752 Katowice, Poland
| | - Boguslaw Okopien
- Department of Internal Medicine and Clinical Pharmacology, Medical University of Silesia, Medyków 18, 40-752 Katowice, Poland
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11
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The effect of fenofibrate on cardiometabolic risk factors in bromocriptine-treated women with mixed dyslipidemia: A pilot study. Pharmacol Rep 2016; 68:185-9. [PMID: 26721371 DOI: 10.1016/j.pharep.2015.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 07/29/2015] [Accepted: 08/12/2015] [Indexed: 10/23/2022]
Abstract
BACKGROUND Elevated prolactin levels are associated with metabolic and hormonal complications. No previous study has investigated the effect of any fibrate on plasma levels of lipids and other cardiometabolic risk factors in patients receiving dopamine agonist therapy. METHODS The study included 36 premenopausal women with mixed dyslipidemia and slightly increased prolactin levels, 17 of whom had already been treated with bromocriptine (5.0-7.5mg daily). The included patients received micronized fenofibrate (200mg daily) for 6 months. Plasma lipids, glucose homeostasis markers, as well as plasma levels of prolactin, uric acid, high-sensitivity C-reactive protein (hsCRP), homocysteine and fibrinogen were determined before and after 12 weeks of fenofibrate therapy. RESULTS Insulin sensitivity was more expressed while baseline plasma levels of hsCRP and fibrinogen were lower in patients treated with bromocriptine than in women not receiving dopamine agonist therapy. Although fenofibrate improved plasma lipids and insulin sensitivity, as well as reduced plasma levels of the investigated cardiometabolic risk factors in both groups of patients, its action on HDL cholesterol, triglycerides, insulin sensitivity, hsCRP and fibrinogen was stronger in subjects receiving bromocriptine. Moreover, only in bromocriptine-naïve patients, fenofibrate increased plasma homocysteine. CONCLUSIONS Our study shows that the effect of fenofibrate on plasma lipids and circulating levels of cardiometabolic risk factors may be potentiated by bromocriptine treatment. They also suggest that hyperprolactinemic women with mixed dyslipidemia and early glucose metabolism abnormalities may receive the greatest benefits from concomitant treatment with a fibrate and bromocriptine.
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12
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Brain signaling systems in the Type 2 diabetes and metabolic syndrome: promising target to treat and prevent these diseases. Future Sci OA 2015; 1:FSO25. [PMID: 28031898 PMCID: PMC5137856 DOI: 10.4155/fso.15.23] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The changes in the brain signaling systems play an important role in etiology and pathogenesis of Type 2 diabetes mellitus (T2DM) and metabolic syndrome (MS), being a possible cause of these diseases. Therefore, their restoration at the early stages of T2DM and MS can be regarded as a promising way to treat and prevent these diseases and their complications. The data on the functional state of the brain signaling systems regulated by insulin, IGF-1, leptin, dopamine, serotonin, melanocortins and glucagon-like peptide-1, in T2DM and MS, are analyzed. The pharmacological approaches to restoration of these systems and improvement of insulin sensitivity, energy expenditure, lipid metabolism, and to prevent diabetic complications are discussed.
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13
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Abstract
The variety of physiological functions controlled by dopamine in the brain and periphery is mediated by the D1, D2, D3, D4 and D5 dopamine GPCRs. Drugs acting on dopamine receptors are significant tools for the management of several neuropsychiatric disorders including schizophrenia, bipolar disorder, depression and Parkinson's disease. Recent investigations of dopamine receptor signalling have shown that dopamine receptors, apart from their canonical action on cAMP-mediated signalling, can regulate a myriad of cellular responses to fine-tune the expression of dopamine-associated behaviours and functions. Such signalling mechanisms may involve alternate G protein coupling or non-G protein mechanisms involving ion channels, receptor tyrosine kinases or proteins such as β-arrestins that are classically involved in GPCR desensitization. Another level of complexity is the growing appreciation of the physiological roles played by dopamine receptor heteromers. Applications of new in vivo techniques have significantly furthered the understanding of the physiological functions played by dopamine receptors. Here we provide an update of the current knowledge regarding the complex biology, signalling, physiology and pharmacology of dopamine receptors.
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14
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The role of type 2 diabetes in neurodegeneration. Neurobiol Dis 2015; 84:22-38. [PMID: 25926349 DOI: 10.1016/j.nbd.2015.04.008] [Citation(s) in RCA: 185] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 04/18/2015] [Accepted: 04/21/2015] [Indexed: 02/07/2023] Open
Abstract
A growing body of evidence links type-2 diabetes (T2D) with dementia and neurodegenerative diseases such as Alzheimer's disease (AD). AD is the most common form of dementia and is characterised neuropathologically by the accumulation of extracellular beta amyloid (Aβ) peptide aggregates and intracellular hyper-phosphorylated tau protein, which are thought to drive and/or accelerate inflammatory and oxidative stress processes leading to neurodegeneration. Although the precise mechanism remains unclear, T2D can exacerbate these neurodegenerative processes. Brain atrophy, reduced cerebral glucose metabolism and CNS insulin resistance are features of both AD and T2D. Cell culture and animal studies have indicated that the early accumulation of Aβ may play a role in CNS insulin resistance and impaired insulin signalling. From the viewpoint of insulin resistance and impaired insulin signalling in the brain, these are also believed to initiate other aspects of brain injury, including inflammatory and oxidative stress processes. Here we review the clinical and experimental pieces of evidence that link these two chronic diseases of ageing, and discuss underlying mechanisms. The evaluation of treatments for the management of diabetes in preclinical, and clinical studies and trials for AD will also be discussed.
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15
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Smaoui MR, Waldispühl J. Complete characterization of the mutation landscape reveals the effect on amylin stability and amyloidogenicity. Proteins 2015; 83:1014-26. [PMID: 25809921 DOI: 10.1002/prot.24795] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Revised: 03/08/2015] [Accepted: 03/10/2015] [Indexed: 12/25/2022]
Abstract
Type-II diabetes is believed to be partially aggravated by the emergence of toxic amylin protein deposits in the extracellular space of the pancreas β-cells. Amylin, the regulatory hormone that is co-secreted with insulin, has been observed to misfold into toxic structures. Pramlintide, an FDA approved injectable amylin analog mutated at positions 25, 28, and 29 was therefore developed to create a more stable, soluble, less-aggregating, and equipotent peptide that is used as an adjunctive therapy for diabetes. However, because Pramlintide is not ideal, researchers have been exploring other amylin analogs as therapeutic replacements. In this work, we assist the finding of optimal analogs by computationally revealing the mutational landscape of amylin. We computed the structure energies of all possible single-point mutations and studied the effect they have on amylin stability and amyloidogenicity. Each of the 37 amylin residues was mutated in silico into the 19 canonical amino acids and an energy function computing the Lennard-Jones, Coulomb and solvation energy was used to analyze changes in stability. The mutation landscape identified amylin's conserved stable regions, residues that can be tweaked to further stabilize structure, regions that are susceptible to mutations, and mutations that are amyloidogenic. We used the single-point mutational landscape data to generate estimations for higher-order multiple-point mutational landscapes and discovered millions of three-point mutations that are more stable and less amyloidogenic than Pramlintide. The landscapes provided an explanation for the effect of the S20G and Q10R mutations on the onset of diabetes of the Chinese and Maori populations, respectively.
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Affiliation(s)
- Mohamed Raef Smaoui
- School of Computer Science, McGill University, Montreal, Quebec, Canada.,McGill Center for Bioinformatics, McGill University, Montreal, Quebec, Canada
| | - Jérôme Waldispühl
- School of Computer Science, McGill University, Montreal, Quebec, Canada.,McGill Center for Bioinformatics, McGill University, Montreal, Quebec, Canada
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Caravaggio F, Borlido C, Hahn M, Feng Z, Fervaha G, Gerretsen P, Nakajima S, Plitman E, Chung JK, Iwata Y, Wilson A, Remington G, Graff-Guerrero A. Reduced insulin sensitivity is related to less endogenous dopamine at D2/3 receptors in the ventral striatum of healthy nonobese humans. Int J Neuropsychopharmacol 2015; 18:pyv014. [PMID: 25716779 PMCID: PMC4540108 DOI: 10.1093/ijnp/pyv014] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2014] [Accepted: 02/04/2015] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Food addiction is a debated topic in neuroscience. Evidence suggests diabetes is related to reduced basal dopamine levels in the nucleus accumbens, similar to persons with drug addiction. It is unknown whether insulin sensitivity is related to endogenous dopamine levels in the ventral striatum of humans. We examined this using the agonist dopamine D2/3 receptor radiotracer [(11)C]-(+)-PHNO and an acute dopamine depletion challenge. In a separate sample of healthy persons, we examined whether dopamine depletion could alter insulin sensitivity. METHODS Insulin sensitivity was estimated for each subject from fasting plasma glucose and insulin using the Homeostasis Model Assessment II. Eleven healthy nonobese and nondiabetic persons (3 female) provided a baseline [(11)C]-(+)-PHNO scan, 9 of which provided a scan under dopamine depletion, allowing estimates of endogenous dopamine at dopamine D2/3 receptor. Dopamine depletion was achieved via alpha-methyl-para-tyrosine (64mg/kg, P.O.). In 25 healthy persons (9 female), fasting plasma and glucose was acquired before and after dopamine depletion. RESULTS Endogenous dopamine at ventral striatum dopamine D2/3 receptor was positively correlated with insulin sensitivity (r(7)=.84, P=.005) and negatively correlated with insulin levels (r(7)=-.85, P=.004). Glucose levels were not correlated with endogenous dopamine at ventral striatum dopamine D2/3 receptor (r(7)=-.49, P=.18). Consistently, acute dopamine depletion in healthy persons significantly decreased insulin sensitivity (t(24)=2.82, P=.01), increased insulin levels (t(24)=-2.62, P=.01), and did not change glucose levels (t(24)=-0.93, P=.36). CONCLUSION In healthy individuals, diminished insulin sensitivity is related to less endogenous dopamine at dopamine D2/3 receptor in the ventral striatum. Moreover, acute dopamine depletion reduces insulin sensitivity. These findings may have important implications for neuropsychiatric populations with metabolic abnormalities.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - Ariel Graff-Guerrero
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada (Mr Caravaggio, Ms Borlido, Ms Feng, Dr Gerretsen, Dr Nakajima, Mr Plitman, Mr Chung, Dr Iwata, Dr Wilson, Dr Remington, and Dr Graff-Guerrero); Institute of Medical Science (Mr Caravaggio, Dr Hahn, Mr Fervaha, Dr Gerretsen, Mr Plitman, Mr Chung, Dr Wilson, Dr Remington, and Dr Graff-Guerrero), and Department of Psychiatry (Drs Hahn, Gerretsen, Nakajima, Iwata, Wilson, Remington, and Graff-Guerrero), University of Toronto, Toronto, Ontario, Canada.
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Phillips LK, Rayner CK, Jones KL, Horowitz M. Measurement of gastric emptying in diabetes. J Diabetes Complications 2014; 28:894-903. [PMID: 25047170 DOI: 10.1016/j.jdiacomp.2014.06.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 06/10/2014] [Indexed: 02/07/2023]
Abstract
There has been a substantial evolution of concepts related to disordered gastric emptying in diabetes. While the traditional focus has hitherto related to the pathophysiology and management of upper gastrointestinal symptoms associated with gastroparesis, it is now apparent that the rate of gastric emptying is central to the regulation of postprandial glycemia. This recognition has stimulated the development of dietary and pharmacologic approaches to optimize glycemic control, at least in part, by slowing gastric emptying. With the increased clinical interest in this area, it has proved necessary to expand the traditional indications for gastric emptying studies, and consider the relative strengths and limitations of available techniques. Scintigraphy remains the 'gold standard' for the measurement of gastric emptying, however, there is a lack of standardization of the technique, and the optimal test meal for the evaluation of gastrointestinal symptoms may be discordant from that which is optimal to assess impaired glycemic control. The stable isotope breath test provides an alternative to scintigraphy and can be performed in an office-based setting. The effect of glucagon-like peptide-1 (GLP-1) and its agonists to reduce postprandial glycemia is dependent on the baseline rate of gastric emptying, as well as the magnitude of slowing. Because the effect of exogenous GLP-1 to slow gastric emptying is subject to tachyphylaxis with sustained receptor exposure, 'short acting' or 'prandial' GLP-1 agonists primarily target postprandial glycemia through slowing of gastric emptying, while 'long acting' or 'non-prandial' agents lower fasting glucose primarily through insulinotropic and glucagonostatic mechanisms. Accordingly, the indications for the therapeutic use of these different agents are likely to vary according to baseline gastric emptying rate and glycemic profiles.
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Affiliation(s)
- Liza K Phillips
- Discipline of Medicine, The University of Adelaide, Australia; NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Australia
| | - Chris K Rayner
- Discipline of Medicine, The University of Adelaide, Australia; NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Australia; Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Australia
| | - Karen L Jones
- Discipline of Medicine, The University of Adelaide, Australia; NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Australia
| | - Michael Horowitz
- Discipline of Medicine, The University of Adelaide, Australia; NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Australia; Endocrine and Metabolic Unit, Royal Adelaide Hospital, Australia.
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Kowalczyk R, Brimble MA, Tomabechi Y, Fairbanks AJ, Fletcher M, Hay DL. Convergent chemoenzymatic synthesis of a library of glycosylated analogues of pramlintide: structure-activity relationships for amylin receptor agonism. Org Biomol Chem 2014; 12:8142-51. [PMID: 25030939 DOI: 10.1039/c4ob01208a] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Pramlintide (Symlin®), a synthetic analogue of the naturally occurring pancreatic hormone amylin, is currently used with insulin in adjunctive therapy for type 1 and type 2 diabetes mellitus. Herein we report a systematic study into the effect that N-glycosylation of pramlintide has on activation of amylin receptors. A highly efficient convergent synthetic route, involving a combination of solid phase peptide synthesis and enzymatic glycosylation, delivered a library of N-glycosylated variants of pramlintide bearing either GlcNAc, the core N-glycan pentasaccharide [Man3(GlcNAc)2] or a complex biantennary glycan [(NeuAcGalGlcNAcMan)2Man(GlcNAc)2] at each of its six asparagine residues. The majority of glycosylated versions of pramlintide were potent receptor agonists, suggesting that N-glycosylation may be used as a tool to optimise the pharmacokinetic properties of pramlintide and so deliver improved therapeutic agents for the treatment of diabetes and obesity.
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Affiliation(s)
- Renata Kowalczyk
- The School of Chemical Sciences, University of Auckland, 23 Symonds St, Auckland 1010, New Zealand.
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Agarwal AK, Sankella S. Phosphatidic acid: a new therapeutic lead to suppress hepatic glucose production. ACTA ACUST UNITED AC 2014; 4:323-326. [PMID: 26413162 DOI: 10.2217/dmt.14.29] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Anil K Agarwal
- Division of Nutrition & Metabolic Diseases, Center for Human Nutrition, Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Shireesha Sankella
- Division of Nutrition & Metabolic Diseases, Center for Human Nutrition, Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
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Vasheka IP, Vesel'skyĭ SP, Horenko ZA, Hrinchenko OA, Karbovs'ka LS, Makarchuk MI. The influence of amylin on the bile acid spectrum in rats. ACTA ACUST UNITED AC 2014. [DOI: 10.15407/fz60.03.046] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Tomabechi Y, Krippner G, Rendle PM, Squire MA, Fairbanks AJ. Glycosylation of Pramlintide: Synthetic Glycopeptides that Display In Vitro and In Vivo Activities as Amylin Receptor Agonists. Chemistry 2013; 19:15084-8. [DOI: 10.1002/chem.201303303] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Indexed: 12/16/2022]
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