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Khare N, Barot M, Singh S, Jain T. Network Pharmacology Reveals Key Targets and Pathways of Madhuca longifolia for Potential Alzheimer's Disease Treatment. Cell Biochem Biophys 2024:10.1007/s12013-024-01389-4. [PMID: 39009828 DOI: 10.1007/s12013-024-01389-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/25/2024] [Indexed: 07/17/2024]
Abstract
Madhuca longifolia, commonly known as the mahua tree, has been traditionally used in medicine due to its anti-inflammatory, anti-diabetic, and antimicrobial properties. Its active compounds help in managing diabetes, alleviating cognitive impairment associated with Alzheimer's disease. Nonetheless, the exact neuroprotective mechanism of Madhuca longifolia against Alzheimer's disease remains unclear. This study looked into possible methods by which Madhuca longifolia protects against Alzheimer's disease using network pharmacology, molecular docking and molecular dynamic simulations studies. By applying pre-screening of active constituents, target prediction, Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway enrichment analysis, our study found that Madhuca longifolia is related to eight active ingredients (Ascorbic acid, Riboflavin, Pantothenic acid, (4 R)-2beta,3beta,23-trihydroxy-oleana-5,12-dien-28-oic acid, Quercetin, Nicotinic acid, Bassiaic acid Thiamine) and 272 common gene targets, with significant involvement in pathways such as PI3K-Akt signaling and neuroactive ligand-receptor interaction. Network analysis demonstrated how Madhuca longifolia can prevent AD by modifying important signalling networks, which may be one of the molecular mechanisms driving the plant's effectiveness against the disease. Molecular docking studies revealed that there were robust binding abilities of Quercetin, Riboflavin and Pantothenic acid to key target proteins AKT1, JUN, and STAT3. Later, molecular dynamic simulations was done to examine the successful activity of the active compounds against potential targets, and it was found that AKT1 and AKT1-Quercetin complex became stable at 260 ps. It may be seen through the study that quercetin may act as a good inhibitor for treatment. This thorough investigation provides a strong basis for future research and development efforts by advancing our understanding of Madhuca longifolia medicinal potential in Alzheimer's disease.
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Affiliation(s)
- Noopur Khare
- Faculty of Biotechnology, Institute of Biosciences and Technology, Shri Ramswaroop Memorial University, Barabanki, Uttar Pradesh, India
- Bhai Gurdas Institute of Engineering and Technology, Sangrur, Punjab, India
| | - Megha Barot
- Department of Environmental Science, Parul Institute of Applied Sciences, Parul University, Vadodara, Gujarat, India
| | - Sachidanand Singh
- Department of Biotechnology, School of Energy and Technology, Pandit Deendayal Energy University, Gandhinagar, Gujarat, India
| | - Tanvi Jain
- Faculty of Biotechnology, Institute of Biosciences and Technology, Shri Ramswaroop Memorial University, Barabanki, Uttar Pradesh, India.
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Werner H, LeRoith D. Hallmarks of cancer: The insulin-like growth factors perspective. Front Oncol 2022; 12:1055589. [PMID: 36479090 PMCID: PMC9720135 DOI: 10.3389/fonc.2022.1055589] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 11/07/2022] [Indexed: 08/30/2023] Open
Abstract
The identification of a series of attributes or hallmarks that are shared by virtually all cancer cells constitutes a true milestone in cancer research. The conceptualization of a catalogue of common genetic, molecular, biochemical and cellular events under a unifying Hallmarks of Cancer idea had a major impact in oncology. Furthermore, the fact that different types of cancer, ranging from pediatric tumors and leukemias to adult epithelial cancers, share a large number of fundamental traits reflects the universal nature of the biological events involved in oncogenesis. The dissection of a complex disease like cancer into a finite directory of hallmarks is of major basic and translational relevance. The role of insulin-like growth factor-1 (IGF1) as a progression/survival factor required for normal cell cycle transition has been firmly established. Similarly well characterized are the biochemical and cellular activities of IGF1 and IGF2 in the chain of events leading from a phenotypically normal cell to a diseased one harboring neoplastic traits, including growth factor independence, loss of cell-cell contact inhibition, chromosomal abnormalities, accumulation of mutations, activation of oncogenes, etc. The purpose of the present review is to provide an in-depth evaluation of the biology of IGF1 at the light of paradigms that emerge from analysis of cancer hallmarks. Given the fact that the IGF1 axis emerged in recent years as a promising therapeutic target, we believe that a careful exploration of this signaling system might be of critical importance on our ability to design and optimize cancer therapies.
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Affiliation(s)
- Haim Werner
- Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Derek LeRoith
- Division of Endocrinology, Diabetes and Bone Diseases, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
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Protective role of IGF-1 and GLP-1 signaling activation in neurological dysfunctions. Neurosci Biobehav Rev 2022; 142:104896. [PMID: 36191807 DOI: 10.1016/j.neubiorev.2022.104896] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 09/09/2022] [Accepted: 09/26/2022] [Indexed: 11/24/2022]
Abstract
Insulin-like growth factor-1 (IGF-1), a pleiotropic polypeptide, plays an essential role in CNS development and maturation. Glucagon-like peptide-1 (GLP-1) is an endogenous incretin hormone that regulates blood glucose levels and fatty acid oxidation in the brain. GLP-1 also exhibits similar functions and growth factor-like properties to IGF-1, which is likely how it exerts its neuroprotective effects. Recent preclinical and clinical evidence indicate that IGF-1 and GLP-1, apart from regulating growth and development, prevent neuronal death mediated by amyloidogenesis, cerebral glucose deprivation, neuroinflammation and apoptosis through modulation of PI3/Akt kinase, mammalian target of rapamycin (mTOR) and mitogen-activated protein kinase (MAPK/ERK). IGF-1 resistance and GLP-1 deficiency impair protective cellular signaling mechanisms, contributing to the progression of neurodegenerative diseases. Over the past decades, IGF-1 and GLP-1 have emerged as an essential component of the neuronal system and as potential therapeutic targets for several neurodegenerative and neuropsychiatric dysfunctions. There is substantial evidence that IGF-1 and GLP-1 analogues penetrate the blood-brain barrier (BBB) and exhibit neuroprotective functions, including synaptic formation, neuronal plasticity, protein synthesis, and autophagy. Conclusively, this review represents the therapeutic potential of IGF-1 and GLP-1 signaling target activators in ameliorating neurological disorders.
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Rahman T, Huang HE, Li Y, Tai AS, Hseih WP, McClung CA, Tseng G. A sparse negative binomial classifier with covariate adjustment for RNA-seq data. Ann Appl Stat 2022. [DOI: 10.1214/21-aoas1532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Tanbin Rahman
- Department of Biostatistics, University of Pittsburgh
| | - Hsin-En Huang
- Institute of Statistics, National Tsing Hua University
| | - Yujia Li
- Department of Biostatistics, University of Pittsburgh
| | - An-Shun Tai
- Institute of Statistics, National Tsing Hua University
| | | | | | - George Tseng
- Department of Biostatistics, University of Pittsburgh
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Pérez MF, Saravia F, Castro MG, Bregonzio C. Editorial: Targeting Neuroinflammation in Central Nervous System Disorders: Uncovering Mechanisms, Pharmacological Targets, and Neuropharmaceutical Developments. Front Pharmacol 2021; 12:771610. [PMID: 34925029 PMCID: PMC8672053 DOI: 10.3389/fphar.2021.771610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 11/16/2021] [Indexed: 11/13/2022] Open
Affiliation(s)
- Mariela Fernanda Pérez
- Instituto de Farmacología Experimental Córdoba (IFEC-CONICET), Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Flavia Saravia
- Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Cordoba, Argentina
| | - María Graciela Castro
- Department of Neurosurgery, School of Medicine, University of Michigan, Ann Arbor, MI, United States
| | - Claudia Bregonzio
- Instituto de Farmacología Experimental Córdoba (IFEC-CONICET), Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
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Manual Acupuncture at ST37 Modulates TRPV1 in Rats with Acute Visceral Hyperalgesia via Phosphatidylinositol 3-Kinase/Akt Pathway. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2021; 2021:5561999. [PMID: 34646326 PMCID: PMC8505093 DOI: 10.1155/2021/5561999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 04/26/2021] [Accepted: 09/09/2021] [Indexed: 11/17/2022]
Abstract
Acupuncture can significantly ameliorate inflammatory pain in acute visceral hyperalgesia. Hyperalgesia is attenuated by inflammatory mediators that activate transient receptor potential vanilloid 1 (TRPV1), and TRPV1 is regulated by nerve growth factor (NGF)-induced phosphatidylinositol 3-kinase (PI3K)/Akt pathway. However, it is unknown whether NGF-induced PI3K/Akt pathway is associated with manual acupuncture (MA). In this study, the effect and mechanism of MA at Shangjuxu (ST37) and Quchi (LI11) were examined using an acetic acid-induced rat model with visceral hyperalgesia. We demonstrated that MA at ST37 significantly decreased abdominal withdrawal reflex (AWR) scores, proinflammatory cytokine expression (TNF-α, IL-1β, and IL-6), and TRPV1 protein and mRNA expression in rats with acute visceral hyperalgesia compared with the untreated controls, while MA at LI11 showed no effect. The effects of MA at ST37 were reversed after treatment with the PI3K agonist IGF-1 30 min before MA. In rats with visceral hyperalgesia, the upregulation of NGF, tropomyosin-receptor-kinase A (TrkA), PI3K, and phosphorylation-Akt (p-Akt) was decreased by MA at ST37, indicating that TRPV1 regulation via the NGF-induced PI3K/Akt pathway plays a vital role in the effects of MA-mediated amelioration of acute visceral hyperalgesia.
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Montivero AJ, Ghersi MS, Silvero C MJ, Artur de la Villarmois E, Catalan-Figueroa J, Herrera M, Becerra MC, Hereñú CB, Pérez MF. Early IGF-1 Gene Therapy Prevented Oxidative Stress and Cognitive Deficits Induced by Traumatic Brain Injury. Front Pharmacol 2021; 12:672392. [PMID: 34234671 PMCID: PMC8255687 DOI: 10.3389/fphar.2021.672392] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 06/08/2021] [Indexed: 12/15/2022] Open
Abstract
Traumatic Brain Injury (TBI) remains a leading cause of morbidity and mortality in adults under 40 years old. Once primary injury occurs after TBI, neuroinflammation and oxidative stress (OS) are triggered, contributing to the development of many TBI-induced neurological deficits, and reducing the probability of critical trauma patients´ survival. Regardless the research investment on the development of anti-inflammatory and neuroprotective treatments, most pre-clinical studies have failed to report significant effects, probably because of the limited blood brain barrier permeability of no-steroidal or steroidal anti-inflammatory drugs. Lately, neurotrophic factors, such as the insulin-like growth factor 1 (IGF-1), are considered attractive therapeutic alternatives for diverse neurological pathologies, as they are neuromodulators linked to neuroprotection and anti-inflammatory effects. Considering this background, the aim of the present investigation is to test early IGF-1 gene therapy in both OS markers and cognitive deficits induced by TBI. Male Wistar rats were injected via Cisterna Magna with recombinant adenoviral vectors containing the IGF-1 gene cDNA 15 min post-TBI. Animals were sacrificed after 60 min, 24 h or 7 days to study the advanced oxidation protein products (AOPP) and malondialdehyde (MDA) levels, to recognize the protein oxidation damage and lipid peroxidation respectively, in the TBI neighboring brain areas. Cognitive deficits were assessed by evaluating working memory 7 days after TBI. The results reported significant increases of AOPP and MDA levels at 60 min, 24 h, and 7 days after TBI in the prefrontal cortex, motor cortex and hippocampus. In addition, at day 7, TBI also reduced working memory performance. Interestingly, AOPP, and MDA levels in the studied brain areas were significantly reduced after IGF-1 gene therapy that in turn prevented cognitive deficits, restoring TBI-animals working memory performance to similar values regarding control. In conclusion, early IGF-1 gene therapy could be considered a novel therapeutic approach to targeting neuroinflammation as well as to preventing some behavioral deficits related to TBI.
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Affiliation(s)
- Agustín J Montivero
- Instituto de Farmacología Experimental de Córdoba (IFEC-CONICET), Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de, Córdoba, Argentina
| | - Marisa S Ghersi
- Instituto de Farmacología Experimental de Córdoba (IFEC-CONICET), Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de, Córdoba, Argentina
| | - M Jazmín Silvero C
- Instituto Multidisciplinario de Biología Vegetal (IMBIV-CONICET), Departamento de Ciencias Farmacéuticas, Facultad de Ciencias Químicas, Universidad Nacional de, Córdoba, Argentina
| | - Emilce Artur de la Villarmois
- Instituto de Farmacología Experimental de Córdoba (IFEC-CONICET), Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de, Córdoba, Argentina
| | - Johanna Catalan-Figueroa
- Instituto de Farmacología Experimental de Córdoba (IFEC-CONICET), Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de, Córdoba, Argentina.,Escuela de Química y Farmacia, Facultad de Medicina, Universidad Católica del Maule, Talca, Chile
| | - Macarena Herrera
- Instituto de Farmacología Experimental de Córdoba (IFEC-CONICET), Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de, Córdoba, Argentina
| | - María Cecilia Becerra
- Instituto Multidisciplinario de Biología Vegetal (IMBIV-CONICET), Departamento de Ciencias Farmacéuticas, Facultad de Ciencias Químicas, Universidad Nacional de, Córdoba, Argentina
| | - Claudia B Hereñú
- Instituto de Farmacología Experimental de Córdoba (IFEC-CONICET), Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de, Córdoba, Argentina
| | - Mariela F Pérez
- Instituto de Farmacología Experimental de Córdoba (IFEC-CONICET), Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de, Córdoba, Argentina
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Maugeri G, D’Agata V, Magrì B, Roggio F, Castorina A, Ravalli S, Di Rosa M, Musumeci G. Neuroprotective Effects of Physical Activity via the Adaptation of Astrocytes. Cells 2021; 10:cells10061542. [PMID: 34207393 PMCID: PMC8234474 DOI: 10.3390/cells10061542] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/14/2021] [Accepted: 06/14/2021] [Indexed: 12/27/2022] Open
Abstract
The multifold benefits of regular physical exercise have been largely demonstrated in human and animal models. Several studies have reported the beneficial effects of physical activity, both in peripheral tissues and in the central nervous system (CNS). Regular exercise improves cognition, brain plasticity, neurogenesis and reduces the symptoms of neurodegenerative diseases, making timeless the principle of “mens sana in corpore sano” (i.e., a healthy mind in a healthy body). Physical exercise promotes morphological and functional changes in the brain, acting not only in neurons but also in astrocytes, which represent the most numerous glial cells in the brain. The multiple effects of exercise on astrocytes comprise the increased number of new astrocytes, the maintenance of basal levels of catecholamine, the increase in glutamate uptake, the major release of trophic factors and better astrocytic coverage of cerebral blood vessels. The purpose of this review is to highlight the effects of exercise on brain function, emphasize the role of astrocytes in the healthy CNS, and provide an update for a better understanding of the effects of physical exercise in the modulation of astrocyte function.
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Affiliation(s)
- Grazia Maugeri
- Department of Biomedical and Biotechnological Sciences, Human, Histology and Movement Science Section, University of Catania, Via S. Sofia n°87, 95100 Catania, Italy; (G.M.); (V.D.); (B.M.); (F.R.); (S.R.); (M.D.R.)
| | - Velia D’Agata
- Department of Biomedical and Biotechnological Sciences, Human, Histology and Movement Science Section, University of Catania, Via S. Sofia n°87, 95100 Catania, Italy; (G.M.); (V.D.); (B.M.); (F.R.); (S.R.); (M.D.R.)
| | - Benedetta Magrì
- Department of Biomedical and Biotechnological Sciences, Human, Histology and Movement Science Section, University of Catania, Via S. Sofia n°87, 95100 Catania, Italy; (G.M.); (V.D.); (B.M.); (F.R.); (S.R.); (M.D.R.)
| | - Federico Roggio
- Department of Biomedical and Biotechnological Sciences, Human, Histology and Movement Science Section, University of Catania, Via S. Sofia n°87, 95100 Catania, Italy; (G.M.); (V.D.); (B.M.); (F.R.); (S.R.); (M.D.R.)
| | - Alessandro Castorina
- Laboratory of Cellular and Molecular Neuroscience (LCMN), School of Life Science, Faculty of Science, University of Technology Sydney, Broadway, NSW 2007, Australia;
- Laboratory of Neural Structure and Function (LNSF), School of Medical Sciences, (Anatomy and Histology), Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia
| | - Silvia Ravalli
- Department of Biomedical and Biotechnological Sciences, Human, Histology and Movement Science Section, University of Catania, Via S. Sofia n°87, 95100 Catania, Italy; (G.M.); (V.D.); (B.M.); (F.R.); (S.R.); (M.D.R.)
| | - Michelino Di Rosa
- Department of Biomedical and Biotechnological Sciences, Human, Histology and Movement Science Section, University of Catania, Via S. Sofia n°87, 95100 Catania, Italy; (G.M.); (V.D.); (B.M.); (F.R.); (S.R.); (M.D.R.)
| | - Giuseppe Musumeci
- Department of Biomedical and Biotechnological Sciences, Human, Histology and Movement Science Section, University of Catania, Via S. Sofia n°87, 95100 Catania, Italy; (G.M.); (V.D.); (B.M.); (F.R.); (S.R.); (M.D.R.)
- Research Center on Motor Activities (CRAM), University of Catania, Via S. Sofia n°97, 95100 Catania, Italy
- Department of Biology, Sbarro Institute for Cancer Research and Molecular Medicine, College of Science and Technology, Temple University, Philadelphia, PA 19122, USA
- Correspondence: ; Tel.: +39-095-378-2043
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Behl T, Kaur I, Sehgal A, Singh S, Zengin G, Negrut N, Nistor-Cseppento DC, Pavel FM, Corb Aron RA, Bungau S. Exploring the Genetic Conception of Obesity via the Dual Role of FoxO. Int J Mol Sci 2021; 22:ijms22063179. [PMID: 33804729 PMCID: PMC8003860 DOI: 10.3390/ijms22063179] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 03/10/2021] [Accepted: 03/18/2021] [Indexed: 12/12/2022] Open
Abstract
Obesity or overweight are not superficial problems, constituting a pressing issue. The obesity index has almost tripled since 1975, which is an alarming state. Most of the individuals are currently becoming overweight or have inappropriate body mass index (BMI) conditions. Obesity is characterized by increased fat accumulation and thus poses a higher health risk. There is increased size and volume of fat cells in the body, which usually accounts for obesity. Many investigations have been carried out in this area, such as behavioral improvements, dietary changes, chemical involvements, etc., but presently no such goals are established to manage these health concerns. Based on previous literature reports and our interpretation, the current review indicates the involvement of various transcriptional and transporter functions in modifying the above-mentioned health conditions. Various transcriptional factors such as Forkhead box O1 (FoxO1) impart a significant effect on the physiology and pathology of metabolic dysfunction such as obesity. FoxO1 plays a dual role whether in the progression or suppression of metabolic processes depending on its targets. Thus, in the current study, will be discussed the dual role of FoxO1 in metabolic conditions (such as obesity), also summarizing the role of various other transcriptional factors involved in obesity.
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Affiliation(s)
- Tapan Behl
- Department of Pharmacology, Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (I.K.); (A.S.); (S.S.)
- Correspondence: (T.B.); (S.B.); Tel.: +40-726-776-588 (S.B.)
| | - Ishnoor Kaur
- Department of Pharmacology, Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (I.K.); (A.S.); (S.S.)
| | - Aayush Sehgal
- Department of Pharmacology, Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (I.K.); (A.S.); (S.S.)
| | - Sukhbir Singh
- Department of Pharmacology, Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (I.K.); (A.S.); (S.S.)
| | - Gokhan Zengin
- Department of Biology, Faculty of Science, Selcuk University Campus, Konya 42130, Turkey;
| | - Nicoleta Negrut
- Department of Psycho-Neuroscience and Recovery, Faculty of Medicine and Pharmacy, University of Oradea, 410073 Oradea, Romania; (N.N.); (D.C.N.-C.)
| | - Delia Carmen Nistor-Cseppento
- Department of Psycho-Neuroscience and Recovery, Faculty of Medicine and Pharmacy, University of Oradea, 410073 Oradea, Romania; (N.N.); (D.C.N.-C.)
| | - Flavia Maria Pavel
- Department of Preclinical Disciplines, Faculty of Medicine and Pharmacy, University of Oradea, 410073 Oradea, Romania; (F.M.P.); (R.A.C.A.)
| | - Raluca Anca Corb Aron
- Department of Preclinical Disciplines, Faculty of Medicine and Pharmacy, University of Oradea, 410073 Oradea, Romania; (F.M.P.); (R.A.C.A.)
| | - Simona Bungau
- Department of Pharmacy, Faculty of Medicine and Pharmacy, University of Oradea, 410028 Oradea, Romania
- Correspondence: (T.B.); (S.B.); Tel.: +40-726-776-588 (S.B.)
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Lee J, Lee J, Lee M, Lim JS, Kim JH, Yu KH, Oh MS, Lee BC. Association between Serum Insulin-Like Growth Factor-1 and Neurological Severity in Acute Ischemic Stroke. J Clin Neurol 2021; 17:206-212. [PMID: 33835740 PMCID: PMC8053552 DOI: 10.3988/jcn.2021.17.2.206] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 11/26/2020] [Accepted: 11/26/2020] [Indexed: 01/01/2023] Open
Abstract
Background and Purpose Serum insulin-like growth factor-1 (IGF-1) is known to have a neuroprotective effect. This study aimed to determine the effects of serum IGF-1 on the severity and clinical outcome of acute ischemic stroke (AIS). Methods This study included 446 patients with AIS who were admitted to Hallym University Sacred Heart Hospital within 7 days of stroke onset from February 2014 to June 2017. Serum IGF-1 levels were measured within 24 hours of admission. Stroke severity was measured using the National Institutes of Health Stroke Scale (NIHSS) score at admission, and the functional outcome at 3 months after symptom onset was assessed using the modified Rankin Scale score. The effects of serum IGF-1 levels on stroke severity and 3-month functional outcomes were analyzed using multivariate logistic regression analysis. Results This study evaluated 379 patients with AIS (age 67.2±12.6 years, mean±standard deviation; 59.9% males) after excluding 67 patients who had a history of previous stroke (n=25) or were lost to follow-up at 3 months (n=42). After adjusting for clinically relevant covariates, a higher serum IGF-1 level was associated with a lower NIHSS score at admission (adjusted odds ratio=0.44, 95% confidence interval=0.24–0.80, p=0.01), while there was no significant association at 3 months. Conclusions This study showed that a higher serum IGF-1 level is associated with a lower NIHSS score at admission but not at 3 months. Further studies are required to clarify the usefulness of the serum IGF-1 level as a prognostic marker for ischemic stroke.
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Affiliation(s)
- Jeeun Lee
- Department of Neurology, Seoul National University Hospital, Seoul, Korea
| | - Jeongjae Lee
- Department of Neurology, Hallym University Sacred Heart Hospital, Anyang, Korea
| | - Minwoo Lee
- Department of Neurology, Hallym University Sacred Heart Hospital, Anyang, Korea
| | - Jae Sung Lim
- Department of Neurology, Hallym University Sacred Heart Hospital, Anyang, Korea
| | - Jin Hyouk Kim
- Department of Neurology, Hallym University Sacred Heart Hospital, Anyang, Korea
| | - Kyung Ho Yu
- Department of Neurology, Hallym University Sacred Heart Hospital, Anyang, Korea
| | - Mi Sun Oh
- Department of Neurology, Hallym University Sacred Heart Hospital, Anyang, Korea.
| | - Byung Chul Lee
- Department of Neurology, Hallym University Sacred Heart Hospital, Anyang, Korea.
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Pilozzi A, Carro C, Huang X. Roles of β-Endorphin in Stress, Behavior, Neuroinflammation, and Brain Energy Metabolism. Int J Mol Sci 2020; 22:E338. [PMID: 33396962 PMCID: PMC7796446 DOI: 10.3390/ijms22010338] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 12/23/2020] [Accepted: 12/26/2020] [Indexed: 12/25/2022] Open
Abstract
β-Endorphins are peptides that exert a wide variety of effects throughout the body. Produced through the cleavage pro-opiomelanocortin (POMC), β-endorphins are the primarily agonist of mu opioid receptors, which can be found throughout the body, brain, and cells of the immune system that regulate a diverse set of systems. As an agonist of the body's opioid receptors, β-endorphins are most noted for their potent analgesic effects, but they also have their involvement in reward-centric and homeostasis-restoring behaviors, among other effects. These effects have implicated the peptide in psychiatric and neurodegenerative disorders, making it a research target of interest. This review briefly summarizes the basics of endorphin function, goes over the behaviors and regulatory pathways it governs, and examines the variability of β-endorphin levels observed between normal and disease/disorder affected individuals.
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Affiliation(s)
| | | | - Xudong Huang
- Neurochemistry Laboratory, Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA; (A.P.); (C.C.)
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Baltazar-Lara R, Ávila-Mendoza J, Martínez-Moreno CG, Carranza M, Pech-Pool S, Vázquez-Martínez O, Díaz-Muñoz M, Luna M, Arámburo C. Neuroprotective Effects of Growth Hormone (GH) and Insulin-Like Growth Factor Type 1 (IGF-1) after Hypoxic-Ischemic Injury in Chicken Cerebellar Cell Cultures. Int J Mol Sci 2020; 22:ijms22010256. [PMID: 33383827 PMCID: PMC7795313 DOI: 10.3390/ijms22010256] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 12/13/2022] Open
Abstract
It has been reported that growth hormone (GH) and insulin-like growth factor 1 (IGF-1) exert protective and regenerative actions in response to neural damage. It is also known that these peptides are expressed locally in nervous tissues. When the central nervous system (CNS) is exposed to hypoxia-ischemia (HI), both GH and IGF-1 are upregulated in several brain areas. In this study, we explored the neuroprotective effects of GH and IGF-1 administration as well as the involvement of these endogenously expressed hormones in embryonic chicken cerebellar cell cultures exposed to an acute HI injury. To induce neural damage, primary cultures were first incubated under hypoxic-ischemic (<5% O2, 1g/L glucose) conditions for 12 h (HI), and then incubated under normal oxygenation and glucose conditions (HI + Ox) for another 24 h. GH and IGF-1 were added either during or after HI, and their effect upon cell viability, apoptosis, or necrosis was evaluated. In comparison with normal controls (Nx, 100%), a significant decrease of cell viability (54.1 ± 2.1%) and substantial increases in caspase-3 activity (178.6 ± 8.7%) and LDH release (538.7 ± 87.8%) were observed in the HI + Ox group. On the other hand, both GH and IGF-1 treatments after injury (HI + Ox) significantly increased cell viability (77.2 ± 4.3% and 72.3 ± 3.9%, respectively) and decreased both caspase-3 activity (118.2 ± 3.8% and 127.5 ± 6.6%, respectively) and LDH release (180.3 ± 21.8% and 261.6 ± 33.9%, respectively). Incubation under HI + Ox conditions provoked an important increase in the local expression of GH (3.2-fold) and IGF-1 (2.5-fold) mRNAs. However, GH gene silencing with a specific small-interfering RNAs (siRNAs) decreased both GH and IGF-1 mRNA expression (1.7-fold and 0.9-fold, respectively) in the HI + Ox group, indicating that GH regulates IGF-1 expression under these incubation conditions. In addition, GH knockdown significantly reduced cell viability (35.9 ± 2.1%) and substantially increased necrosis, as determined by LDH release (1011 ± 276.6%). In contrast, treatments with GH and IGF-1 stimulated a partial recovery of cell viability (45.2 ± 3.7% and 53.7 ± 3.2%) and significantly diminished the release of LDH (320.1 ± 25.4% and 421.7 ± 62.2%), respectively. Our results show that GH, either exogenously administered and/or locally expressed, can act as a neuroprotective factor in response to hypoxic-ischemic injury, and that this effect may be mediated, at least partially, through IGF-1 expression.
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Affiliation(s)
- Rosario Baltazar-Lara
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus Juriquilla, Universidad Nacional Autónoma de México, Querétaro 76230, Mexico; (R.B.-L.); (J.Á.-M.); (C.G.M.-M.); (M.C.); (S.P.-P.); (O.V.-M.); (M.D.-M.)
| | - José Ávila-Mendoza
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus Juriquilla, Universidad Nacional Autónoma de México, Querétaro 76230, Mexico; (R.B.-L.); (J.Á.-M.); (C.G.M.-M.); (M.C.); (S.P.-P.); (O.V.-M.); (M.D.-M.)
- Department of Molecular, Cellular and Developmental Biology, The University of Michigan, Ann Arbor, MI 48109, USA
| | - Carlos G. Martínez-Moreno
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus Juriquilla, Universidad Nacional Autónoma de México, Querétaro 76230, Mexico; (R.B.-L.); (J.Á.-M.); (C.G.M.-M.); (M.C.); (S.P.-P.); (O.V.-M.); (M.D.-M.)
| | - Martha Carranza
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus Juriquilla, Universidad Nacional Autónoma de México, Querétaro 76230, Mexico; (R.B.-L.); (J.Á.-M.); (C.G.M.-M.); (M.C.); (S.P.-P.); (O.V.-M.); (M.D.-M.)
| | - Santiago Pech-Pool
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus Juriquilla, Universidad Nacional Autónoma de México, Querétaro 76230, Mexico; (R.B.-L.); (J.Á.-M.); (C.G.M.-M.); (M.C.); (S.P.-P.); (O.V.-M.); (M.D.-M.)
| | - Olivia Vázquez-Martínez
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus Juriquilla, Universidad Nacional Autónoma de México, Querétaro 76230, Mexico; (R.B.-L.); (J.Á.-M.); (C.G.M.-M.); (M.C.); (S.P.-P.); (O.V.-M.); (M.D.-M.)
| | - Mauricio Díaz-Muñoz
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus Juriquilla, Universidad Nacional Autónoma de México, Querétaro 76230, Mexico; (R.B.-L.); (J.Á.-M.); (C.G.M.-M.); (M.C.); (S.P.-P.); (O.V.-M.); (M.D.-M.)
| | - Maricela Luna
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus Juriquilla, Universidad Nacional Autónoma de México, Querétaro 76230, Mexico; (R.B.-L.); (J.Á.-M.); (C.G.M.-M.); (M.C.); (S.P.-P.); (O.V.-M.); (M.D.-M.)
- Correspondence: (M.L.); (C.A.); Tel.: +52-55-5623-4066 (M.L.); +52-55-5623-4065 (C.A.); Fax: +52-55-5623-4005 (M.L. & C.A.)
| | - Carlos Arámburo
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus Juriquilla, Universidad Nacional Autónoma de México, Querétaro 76230, Mexico; (R.B.-L.); (J.Á.-M.); (C.G.M.-M.); (M.C.); (S.P.-P.); (O.V.-M.); (M.D.-M.)
- Correspondence: (M.L.); (C.A.); Tel.: +52-55-5623-4066 (M.L.); +52-55-5623-4065 (C.A.); Fax: +52-55-5623-4005 (M.L. & C.A.)
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Mansoor H, Tan HC, Lin MTY, Mehta JS, Liu YC. Diabetic Corneal Neuropathy. J Clin Med 2020; 9:jcm9123956. [PMID: 33291308 PMCID: PMC7762152 DOI: 10.3390/jcm9123956] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 11/26/2020] [Accepted: 12/03/2020] [Indexed: 12/14/2022] Open
Abstract
Diabetic keratopathy (DK) is a common, but underdiagnosed, ocular complication of diabetes mellitus (DM) that has a significant economic burden. It is characterised by progressive damage of corneal nerves, due to DM-induced chronic hyperglycaemia and its associated metabolic changes. With advances in corneal nerve imaging and quantitative analytic tools, studies have shown that the severity of diabetic corneal neuropathy correlates with the status of diabetic peripheral neuropathy. The corneal nerve plexus is, therefore, considered as an important surrogate marker of diabetic peripheral neuropathy and helps in the evaluation of interventional efficacy in the management of DM. The clinical manifestations of DK depend on the disease severity and vary from decreased corneal sensitivity to sight-threatening corneal infections and neurotrophic ulcers. The severity of diabetic corneal neuropathy and resultant DK determines its management plan, and a step-wise approach is generally suggested. Future work would focus on the exploration of biomarkers for diabetic corneal neuropathy, the development of new treatment for corneal nerve protection, and the improvement in the clinical assessment, as well as current imaging technique and analysis, to help clinicians detect diabetic corneal neuropathy earlier and monitor the sub-clinical progression more reliably.
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Affiliation(s)
- Hassan Mansoor
- Al Shifa Trust Eye Hospital, Rawalpindi 44000, Pakistan;
| | - Hong Chang Tan
- Department of Endocrinology, Singapore General Hospital, Singapore 169608, Singapore;
| | - Molly Tzu-Yu Lin
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore 169856, Singapore; (M.T.-Y.L.); (J.S.M.)
| | - Jodhbir S. Mehta
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore 169856, Singapore; (M.T.-Y.L.); (J.S.M.)
- Cornea and External Eye Diseases, Singapore National Eye Centre, Singapore 168751, Singapore
- Eye-Academic Clinical Program, Duke-National University Singapore Graduate Medical School, Singapore 169857, Singapore
| | - Yu-Chi Liu
- Tissue Engineering and Cell Therapy Group, Singapore Eye Research Institute, Singapore 169856, Singapore; (M.T.-Y.L.); (J.S.M.)
- Cornea and External Eye Diseases, Singapore National Eye Centre, Singapore 168751, Singapore
- Eye-Academic Clinical Program, Duke-National University Singapore Graduate Medical School, Singapore 169857, Singapore
- Correspondence: ; Tel.: +65-65-767-246; Fax: +65-62-277-290
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Signaling Network of Forkhead Family of Transcription Factors (FOXO) in Dietary Restriction. Cells 2019; 9:cells9010100. [PMID: 31906091 PMCID: PMC7016766 DOI: 10.3390/cells9010100] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 12/25/2019] [Accepted: 12/29/2019] [Indexed: 02/07/2023] Open
Abstract
Dietary restriction (DR), which is defined as a reduction of particular or total nutrient intake without causing malnutrition, has been proved to be a robust way to extend both lifespan and health-span in various species from yeast to mammal. However, the molecular mechanisms by which DR confers benefits on longevity were not yet fully elucidated. The forkhead box O transcription factors (FOXOs), identified as downstream regulators of the insulin/IGF-1 signaling pathway, control the expression of many genes regulating crucial biological processes such as metabolic homeostasis, redox balance, stress response and cell viability and proliferation. The activity of FOXOs is also mediated by AMP-activated protein kinase (AMPK), sirtuins and the mammalian target of rapamycin (mTOR). Therefore, the FOXO-related pathways form a complex network critical for coordinating a response to environmental fluctuations in order to maintain cellular homeostasis and to support physiological aging. In this review, we will focus on the role of FOXOs in different DR interventions. As different DR regimens or calorie (energy) restriction mimetics (CRMs) can elicit both distinct and overlapped DR-related signaling pathways, the benefits of DR may be maximized by combining diverse forms of interventions. In addition, a better understanding of the precise role of FOXOs in different mechanistic aspects of DR response would provide clear cellular and molecular insights on DR-induced increase of lifespan and health-span.
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Maekawa T, Ogasawara R, Tsutaki A, Lee K, Nakada S, Nakazato K, Ishii N. Electrically evoked local muscle contractions cause an increase in hippocampal BDNF. Appl Physiol Nutr Metab 2018; 43:491-496. [PMID: 29558209 DOI: 10.1139/apnm-2017-0536] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
High-intensity exercise has recently been shown to cause an increase in brain-derived neurotropic factor (BDNF) in the hippocampus. Some studies have suggested that myokines secreted from contracting skeletal muscle, such as irisin (one of the truncated form of fibronectin type III domain-containing protein 5 (FNDC5)), play important roles in this process. Thus, we hypothesized that locally evoked muscle contractions may cause an increase of BDNF in the hippocampus through some afferent mechanisms. Under anesthesia, Sprague-Dawley rats were fixed on a custom-made dynamometer and their triceps surae muscles were made to maximally contract via delivery of electric stimulations of the sciatic nerve (100 Hz with 1-ms pulse and 3-s duration). Following 50 repeated maximal isometric contractions, the protein expressions of BDNF and activation of its receptor in the hippocampus significantly increased compared with the sham-operated control rats. However, the expression of both BDNF and FNDC5 within stimulated muscles did not significantly increase, nor did their serum concentrations change. These results indicate that local muscular contractions under unconsciousness can induce BDNF expression in the hippocampus. This effect may be mediated by peripheral reception of muscle contraction, but not by systemic factors.
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Affiliation(s)
- Takahiro Maekawa
- a Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Riki Ogasawara
- a Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan.,b Department of Life and Materials Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
| | - Arata Tsutaki
- c Graduate School of Health and Sport Sciences, Nippon Sport Science University, Tokyo 158-8508, Japan
| | - Kihyuk Lee
- c Graduate School of Health and Sport Sciences, Nippon Sport Science University, Tokyo 158-8508, Japan
| | - Satoshi Nakada
- a Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Koichi Nakazato
- c Graduate School of Health and Sport Sciences, Nippon Sport Science University, Tokyo 158-8508, Japan
| | - Naokata Ishii
- a Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
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Ribarič S. Peptides as Potential Therapeutics for Alzheimer's Disease. Molecules 2018; 23:E283. [PMID: 29385735 PMCID: PMC6017258 DOI: 10.3390/molecules23020283] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 01/26/2018] [Accepted: 01/28/2018] [Indexed: 12/22/2022] Open
Abstract
Intracellular synthesis, folding, trafficking and degradation of proteins are controlled and integrated by proteostasis. The frequency of protein misfolding disorders in the human population, e.g., in Alzheimer's disease (AD), is increasing due to the aging population. AD treatment options are limited to symptomatic interventions that at best slow-down disease progression. The key biochemical change in AD is the excessive accumulation of per-se non-toxic and soluble amyloid peptides (Aβ(1-37/44), in the intracellular and extracellular space, that alters proteostasis and triggers Aβ modification (e.g., by reactive oxygen species (ROS)) into toxic intermediate, misfolded soluble Aβ peptides, Aβ dimers and Aβ oligomers. The toxic intermediate Aβ products aggregate into progressively less toxic and less soluble protofibrils, fibrils and senile plaques. This review focuses on peptides that inhibit toxic Aβ oligomerization, Aβ aggregation into fibrils, or stabilize Aβ peptides in non-toxic oligomers, and discusses their potential for AD treatment.
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Affiliation(s)
- Samo Ribarič
- Institute of Pathophysiology, Faculty of Medicine, Zaloška 4, SI-1000 Ljubljana, Slovenia.
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17
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Stuard WL, Titone R, Robertson DM. Tear Levels of Insulin-Like Growth Factor Binding Protein 3 Correlate With Subbasal Nerve Plexus Changes in Patients With Type 2 Diabetes Mellitus. Invest Ophthalmol Vis Sci 2017; 58:6105-6112. [PMID: 29214310 PMCID: PMC5718599 DOI: 10.1167/iovs.17-22425] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Purpose This study investigated the expression of insulin-like growth factor binding protein-3 (IGFBP-3) in basal tears of patients with type 2 diabetes mellitus compared to nondiabetic controls; and correlated tear levels of IGFBP-3 with morphologic changes in the subbasal nerve plexus and density of basal corneal epithelial cells. Methods This was a single visit, cross-sectional study. Diabetic and control subjects were matched for age, sex, smoking status, and body mass index. Tear levels of IGFBP-3 were measured using ELISA. Corneal nerve and basal epithelial cell changes were measured using in vivo confocal microscopy. Results Tear levels of IGFBP-3 were 3.5-fold higher in those with diabetes. Patients with diabetes also showed a reduction in nerve fiber layer, nerve branch density, and corneal basal epithelial cell density. There was no significant difference in corneal sensitivity. IGFBP-3 levels were highly correlated with nerve fiber length and branch density; while hemoglobin (Hb)A1c was only moderately correlated. There were no significant differences in the clinical or subjective signs of dry eye between groups, indicating that tear levels of IGFBP-3 and corneal nerve changes were not due to the presence of mild dry eye. Conclusions These findings indicate that tear levels of IGFBP-3 are more tightly correlated to nerve fiber changes in diabetes than HbA1c. Future studies that stratify the severity of diabetic disease with tear levels of IGFBP-3 are needed to validate this finding.
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Affiliation(s)
- Whitney L Stuard
- The Department of Ophthalmology, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Rossella Titone
- The Department of Ophthalmology, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Danielle M Robertson
- The Department of Ophthalmology, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
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Song Z, Du Y, Tao Y. Blockade of sonic hedgehog signaling decreases viability and induces apoptosis in retinoblastoma cells: The key role of the PI3K/Akt pathway. Oncol Lett 2017; 14:4099-4105. [PMID: 28943916 PMCID: PMC5604099 DOI: 10.3892/ol.2017.6701] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 03/23/2017] [Indexed: 12/24/2022] Open
Abstract
Retinoblastoma (RB) is the most common type of malignant intraocular cancer in teenagers. One of the proteins abnormally expressed during oncogenesis of RB is sonic hedgehog (SHH), which possesses the capability to selectively activate transcription factors of different genes. However, the detailed function of SHH in RB remains unknown. Thus, the present study sought to investigate the role of SHH in the development of RB. The human RB WERI-Rb-1 cell line was used as an in vitro model for the knockdown of SHH by a specific short hairpin RNA (shRNA). To assess the effect of SHH inhibition on cell growth and apoptosis, cell viability, colony formation and flow cytometry assays were conducted. WERI-Rb-1 cells transfected with an shRNA targeting SHH were treated with the phosphoinositide-3 kinase (PI3K)/Akt agonist insulin-like growth factor 1 (IGF-1) to investigate the possible mechanism by which SHH promotes RB. The present results revealed that the silencing of SHH induced G1 cell-cycle arrest and apoptosis in WERI-Rb-1 cells and led to a decrease in cell viability, indicating that SHH has a critical role in the determination of RB cell survival. Moreover, according to the results of the IGF-1 assays, suppression of PI3K/Akt was a prerequisite for SHH inhibition, illuminating its potential role in the treatment of RB. The findings outlined in the present study elucidate a clear link between SHH and the PI3K/Akt pathway in RB cell survival, which could provide valuable inspiration for the advancement of therapies against RB.
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Affiliation(s)
- Zhidu Song
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun, Jilin 130041, P.R. China
| | - Yuanyuan Du
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun, Jilin 130041, P.R. China
| | - Ying Tao
- Department of Anesthesiology, The Third Hospital of Jilin University, Changchun, Jilin 130033, P.R. China
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Martín-Montañez E, Millon C, Boraldi F, Garcia-Guirado F, Pedraza C, Lara E, Santin LJ, Pavia J, Garcia-Fernandez M. IGF-II promotes neuroprotection and neuroplasticity recovery in a long-lasting model of oxidative damage induced by glucocorticoids. Redox Biol 2017; 13:69-81. [PMID: 28575743 PMCID: PMC5454142 DOI: 10.1016/j.redox.2017.05.012] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 05/23/2017] [Indexed: 11/05/2022] Open
Abstract
Insulin-like growth factor-II (IGF-II) is a naturally occurring hormone that exerts neurotrophic and neuroprotective properties in a wide range of neurodegenerative diseases and ageing. Accumulating evidence suggests that the effects of IGF-II in the brain may be explained by its binding to the specific transmembrane receptor, IGFII/M6P receptor (IGF-IIR). However, relatively little is known regarding the role of IGF-II through IGF-IIR in neuroprotection. Here, using adult cortical neuronal cultures, we investigated whether IGF-II exhibits long-term antioxidant effects and neuroprotection at the synaptic level after oxidative damage induced by high and transient levels of corticosterone (CORT). Furthermore, the involvement of the IGF-IIR was also studied to elucidate its role in the neuroprotective actions of IGF-II. We found that neurons treated with IGF-II after CORT incubation showed reduced oxidative stress damage and recovered antioxidant status (normalized total antioxidant status, lipid hydroperoxides and NAD(P) H:quinone oxidoreductase activity). Similar results were obtained when mitochondria function was analysed (cytochrome c oxidase activity, mitochondrial membrane potential and subcellular mitochondrial distribution). Furthermore, neuronal impairment and degeneration were also assessed (synaptophysin and PSD-95 expression, presynaptic function and FluoroJade B® stain). IGF-II was also able to recover the long-lasting neuronal cell damage. Finally, the effects of IGF-II were not blocked by an IGF-IR antagonist, suggesting the involvement of IGF-IIR. Altogether these results suggest that, in or model, IGF-II through IGF-IIR is able to revert the oxidative damage induced by CORT. In accordance with the neuroprotective role of the IGF-II/IGF-IIR reported in our study, pharmacotherapy approaches targeting this pathway may be useful for the treatment of diseases associated with cognitive deficits (i.e., neurodegenerative disorders, depression, etc.). First evidence that IGF-II reverts oxidative synaptic damage produced by corticoids. IGF-II recovers mitochondrial function in synapses after oxidative damage. IGF-II restores mitochondrial distribution in neurons after oxidative damage. Evidence of the involvement of IGF-II receptor in the recovery of synaptic function. IGF-II reverts neurodegeneration induced by oxidative damage produced by corticoids.
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Affiliation(s)
- E Martín-Montañez
- Department of Pharmacology and Paediatrics, Málaga University, Biomedical Research Institute of Málaga (IBIMA), Málaga, Spain
| | - C Millon
- Department of Human Physiology, Málaga University, Biomedical Research Institute of Málaga (IBIMA), Málaga, Spain
| | - F Boraldi
- Department of Life Sciences, University of Modena e Reggio Emilia, Modena, Italy
| | - F Garcia-Guirado
- Department of Human Physiology, Málaga University, Biomedical Research Institute of Málaga (IBIMA), Málaga, Spain
| | - C Pedraza
- Department of Psychobiology, Málaga University, Biomedical Research Institute of Málaga (IBIMA), Málaga, Spain
| | - E Lara
- Department of Human Physiology, Málaga University, Biomedical Research Institute of Málaga (IBIMA), Málaga, Spain
| | - L J Santin
- Department of Psychobiology, Málaga University, Biomedical Research Institute of Málaga (IBIMA), Málaga, Spain
| | - J Pavia
- Department of Pharmacology and Paediatrics, Málaga University, Biomedical Research Institute of Málaga (IBIMA), Málaga, Spain.
| | - M Garcia-Fernandez
- Department of Human Physiology, Málaga University, Biomedical Research Institute of Málaga (IBIMA), Málaga, Spain.
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N-Acetylcysteine in Combination with IGF-1 Enhances Neuroprotection against Proteasome Dysfunction-Induced Neurotoxicity in SH-SY5Y Cells. PARKINSONS DISEASE 2016; 2016:6564212. [PMID: 27774335 PMCID: PMC5059605 DOI: 10.1155/2016/6564212] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 08/19/2016] [Accepted: 08/28/2016] [Indexed: 11/17/2022]
Abstract
Ubiquitin proteasome system (UPS) dysfunction has been implicated in the development of many neuronal disorders, including Parkinson's disease (PD). Previous studies focused on individual neuroprotective agents and their respective abilities to prevent neurotoxicity following a variety of toxic insults. However, the effects of the antioxidant N-acetylcysteine (NAC) on proteasome impairment-induced apoptosis have not been well characterized in human neuronal cells. The aim of this study was to determine whether cotreatment of NAC and insulin-like growth factor-1 (IGF-1) efficiently protected against proteasome inhibitor-induced cytotoxicity in SH-SY5Y cells. Our results demonstrate that the proteasome inhibitor, MG132, initiates poly(ADP-ribose) polymerase (PARP) cleavage, caspase 3 activation, and nuclear condensation and fragmentation. In addition, MG132 treatment leads to endoplasmic reticulum (ER) stress and autophagy-mediated cell death. All of these events can be attenuated without obvious reduction of MG132 induced protein ubiquitination by first treating the cells with NAC and IGF-1 separately or simultaneously prior to exposure to MG132. Moreover, our data demonstrated that the combination of the two proved to be significantly more effective for neuronal protection. Therefore, we conclude that the simultaneous use of growth/neurotrophic factors and a free radical scavenger may increase overall protection against UPS dysfunction-mediated cytotoxicity and neurodegeneration.
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Kong D, Gong L, Arnold E, Shanmugam S, Fort PE, Gardner TW, Abcouwer SF. Insulin-like growth factor 1 rescues R28 retinal neurons from apoptotic death through ERK-mediated BimEL phosphorylation independent of Akt. Exp Eye Res 2016; 151:82-95. [PMID: 27511131 DOI: 10.1016/j.exer.2016.08.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 06/27/2016] [Accepted: 08/05/2016] [Indexed: 10/21/2022]
Abstract
Insulin-like growth factor 1 (IGF-1) can provide long-term neurotrophic support by activation of Akt, inhibition of FoxO nuclear localization and suppression of Bim gene transcription in multiple neuronal systems. However, MEK/ERK activation can also promote neuron survival through phosphorylation of BimEL. We explored the contribution of the PI3K/Akt/FoxO and MEK/ERK/BimEL pathways in IGF-1 stimulated survival after serum deprivation (SD) of R28 cells differentiated to model retinal neurons. IGF-1 caused rapid activation of Akt leading to FoxO1/3-T32/T24 phosphorylation, and prevented FoxO1/3 nuclear translocation and Bim mRNA upregulation in response to SD. IGF-1 also caused MAPK/MEK pathway activation as indicated by ERK1/2-T202/Y204 and Bim-S65 phosphorylation. Overexpression of FoxO1 increased Bim mRNA expression and amplified the apoptotic response to SD without shifting the serum response curve. Inhibition of Akt activation with LY294002 or by Rictor knockdown did not block the protective effect of IGF-1, while inhibition of MEK activity with PD98059 prevented Bim phosphorylation and blocked IGF-1 protection. In addition, knockdown of Bim expression was protective during SD, while co-silencing of FoxO1 and Fox03 expression had little effect. Thus, the PI3K/Akt/FoxO pathway was not essential for protection from SD-induced apoptosis by IGF-1 in R28 cells. Instead, IGF-1 protection was dependent on activation of the MEK/ERK pathway leading to BimEL phosphorylation, which is known to prevent Bax/Bak oligomerization and activation of the intrinsic mitochondrial apoptosis pathway. These studies demonstrate the requirement of the MEK/ERK pathway in a model of retinal neuron cell survival and highlight the cell specificity for IGF-1 signaling in this response.
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Affiliation(s)
- Dejuan Kong
- Department of Ophthalmology and Visual Sciences, University of Michigan Kellogg Eye Center, Ann Arbor, MI, United States
| | - Lijie Gong
- Department of Ophthalmology and Visual Sciences, University of Michigan Kellogg Eye Center, Ann Arbor, MI, United States
| | - Edith Arnold
- Department of Ophthalmology and Visual Sciences, University of Michigan Kellogg Eye Center, Ann Arbor, MI, United States
| | - Sumathi Shanmugam
- Department of Ophthalmology and Visual Sciences, University of Michigan Kellogg Eye Center, Ann Arbor, MI, United States
| | - Patrice E Fort
- Department of Ophthalmology and Visual Sciences, University of Michigan Kellogg Eye Center, Ann Arbor, MI, United States
| | - Thomas W Gardner
- Department of Ophthalmology and Visual Sciences, University of Michigan Kellogg Eye Center, Ann Arbor, MI, United States
| | - Steven F Abcouwer
- Department of Ophthalmology and Visual Sciences, University of Michigan Kellogg Eye Center, Ann Arbor, MI, United States.
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Quail DF, Bowman RL, Akkari L, Quick ML, Schuhmacher AJ, Huse JT, Holland EC, Sutton JC, Joyce JA. The tumor microenvironment underlies acquired resistance to CSF-1R inhibition in gliomas. Science 2016; 352:aad3018. [PMID: 27199435 DOI: 10.1126/science.aad3018] [Citation(s) in RCA: 459] [Impact Index Per Article: 57.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 04/08/2016] [Indexed: 11/02/2022]
Abstract
Macrophages accumulate with glioblastoma multiforme (GBM) progression and can be targeted via inhibition of colony-stimulating factor-1 receptor (CSF-1R) to regress high-grade tumors in animal models of this cancer. However, whether and how resistance emerges in response to sustained CSF-1R blockade is unknown. We show that although overall survival is significantly prolonged, tumors recur in >50% of mice. Gliomas reestablish sensitivity to CSF-1R inhibition upon transplantation, indicating that resistance is tumor microenvironment-driven. Phosphatidylinositol 3-kinase (PI3K) pathway activity was elevated in recurrent GBM, driven by macrophage-derived insulin-like growth factor-1 (IGF-1) and tumor cell IGF-1 receptor (IGF-1R). Combining IGF-1R or PI3K blockade with CSF-1R inhibition in recurrent tumors significantly prolonged overall survival. Our findings thus reveal a potential therapeutic approach for treating resistance to CSF-1R inhibitors.
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Affiliation(s)
- Daniela F Quail
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center (MSKCC), New York, NY 10065, USA
| | - Robert L Bowman
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center (MSKCC), New York, NY 10065, USA
| | - Leila Akkari
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center (MSKCC), New York, NY 10065, USA. Department of Oncology, University of Lausanne, CH-1066, Lausanne, Switzerland. Ludwig Institute for Cancer Research, University of Lausanne, CH-1066, Lausanne, Switzerland
| | - Marsha L Quick
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center (MSKCC), New York, NY 10065, USA
| | - Alberto J Schuhmacher
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center (MSKCC), New York, NY 10065, USA
| | - Jason T Huse
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Eric C Holland
- Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, WA 98109, USA
| | - James C Sutton
- Novartis Institutes for Biomedical Research, Emeryville, CA 94608, USA
| | - Johanna A Joyce
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center (MSKCC), New York, NY 10065, USA. Department of Oncology, University of Lausanne, CH-1066, Lausanne, Switzerland. Ludwig Institute for Cancer Research, University of Lausanne, CH-1066, Lausanne, Switzerland.
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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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Zeng Z, Wang H, Shang F, Zhou L, Little PJ, Quirion R, Zheng W. Lithium ions attenuate serum-deprivation-induced apoptosis in PC12 cells through regulation of the Akt/FoxO1 signaling pathways. Psychopharmacology (Berl) 2016; 233:785-94. [PMID: 26626328 DOI: 10.1007/s00213-015-4168-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2015] [Accepted: 11/10/2015] [Indexed: 11/26/2022]
Abstract
RATIONALE Lithium is currently used in the treatment of mental illness. We have previously reported that lithium stimulated the protein kinase B/Forkhead box O1 (Akt/FoxO1) pathway in rats. However, little information is available regarding its neuroprotective role of this pathway and underlying mechanisms. OBJECTIVES PC12 cells treated with serum deprivation were used as a toxicity model to study the protective effect of lithium and its underlying mechanisms. METHODS Cell viability was determined by methyl thiazolyl tetrazolium assay and Hoechst staining. FoxO1 subcellular location and its overexpression were used to study the underlying mechanisms. Various pathway inhibitors were used to investigate the possible pathways, while the phosphorylation of Akt and FoxO1 was analyzed by Western blot. RESULTS Lithium pretreatment dose-dependently reduced PC12 cell apoptosis induced by serum starvation. The protective effect of lithium was abolished by LY294002, a PI3K-specific inhibitor, and Akt inhibitor Akt inhibitor VIII, whereas mitogen-activated protein kinase kinase (MEK kinase) inhibitor U0126 had no effect. Lithium induced the phosphorylation of Akt and FoxO1 in a time- and concentration-dependent manner. Lithium-induced phosphorylation of Akt and FoxO1 is mediated by the PI3K/Akt pathway. Serum deprivation caused nuclear translocation of FoxO1 while application of lithium reversed the effect of serum deprivation. Moreover, overexpression of FoxO1 enhanced cell apoptosis induced by serum withdrawal. Finally, lithium was found to reduce the exogenous and endogenous FoxO1 protein levels in PC12 cells in a concentration-dependent fashion. CONCLUSIONS The protective effect of lithium against serum starvation cell death is mediated by the PI3K/Akt/FoxO1 pathway.
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Affiliation(s)
- Zhiwen Zeng
- Faculty of Health Science, University of Macau, Room 4021, Building E12, Avenida de Universidade Taipa, Macau, People's Republic of China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Collaborative Innovation Center for Neurogenetics and Channelopathies, Institute of Neuroscience, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, People's Republic of China
| | - Haitao Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center and Neurophamacology, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510060, People's Republic of China
| | - Fu Shang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center and Neurophamacology, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510060, People's Republic of China
| | - Lihua Zhou
- Zhongshan Medical School, Sun Yat-Sen University, Guangzhou, 510060, People's Republic of China
| | - Peter J Little
- School of Pharmacy, Pharmacy Australia Centre of Excellence, The University of Queensland, 20 Cornwall St, Woolloongabba, QLD, 4102, Australia
| | - Remi Quirion
- Douglas Hospital Research Center, McGill University, Montreal, Canada
| | - Wenhua Zheng
- Faculty of Health Science, University of Macau, Room 4021, Building E12, Avenida de Universidade Taipa, Macau, People's Republic of China.
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Combining Normobaric Oxygen with Ethanol or Hypothermia Prevents Brain Damage from Thromboembolic Stroke via PKC-Akt-NOX Modulation. Mol Neurobiol 2016; 54:1263-1277. [PMID: 26820681 DOI: 10.1007/s12035-016-9695-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 01/05/2016] [Indexed: 01/01/2023]
Abstract
In a thromboembolic stroke model after reperfusion by recombinant tissue plasminogen activator (rt-PA), we aimed to determine whether therapeutic hypothermia (TH) and ethanol (EtOH) in combination with low concentration (60 %) of normobaric oxygen (NBO) enhanced neuroprotection, as compared to using each of these agents alone. We further aimed to elucidate a potential role of the NADPH oxidase (NOX), phosphorylated protein kinase B (Akt), and protein kinase C-δ (PKC-δ) pathway in oxidative stress and neuroprotection. In Sprague-Dawley rats, a focal middle cerebral artery (MCA) occlusion was induced by an autologous embolus in the following experimental groups: rt-PA treatment alone, rt-PA + NBO treatment, rt-PA + TH at 33 °C, rt-PA + EtOH, rt-PA + NBO + EtOH, rt-PA + NBO + TH, rt-PA + NOX inhibitor, rt-PA + EtOH + NOX inhibitor, or rt-PA + EtOH + Akt inhibitor. Control groups included sham-operated without stroke or stroke without treatment. Infarct volume and neurological deficit were assessed at 24 h after rt-PA-induced reperfusion with or without treatments. ROS levels, NOX activity, and the protein expression of NOX subunits p22phox, p47phox, p67phox, gp91phox, as well as PKC-δ and phosphorylated Akt were measured at 3 and 24 h after rt-PA-induced reperfusion. Following rt-PA in thromboembolic stroke rats, NBO combined with TH or EtOH more effectively decreased infarct volume and neurological deficit, as well as reactive oxygen species (ROS) production than with any of the used monotherapies. NOX activity and subunit expressions were downregulated and temporally associated with reduced PKC-δ and increased p-Akt expression. The present study demonstrated that combining NBO with either TH or EtOH conferred similar neuroprotection via modulation of NOX activation. The results suggest a role of Akt in NOX activation and implicate an upstream PKC-δ pathway in the Akt regulation of NOX. It is possible to substitute EtOH for TH, thus circumventing the difficulties in clinical application of TH through the comparatively easier usage of EtOH as a potential stroke management.
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Martins IJ. Anti-Aging Genes Improve Appetite Regulation and Reverse Cell Senescence and Apoptosis in Global Populations. ACTA ACUST UNITED AC 2016. [DOI: 10.4236/aar.2016.51002] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Dávila D, Fernández S, Torres-Alemán I. Astrocyte Resilience to Oxidative Stress Induced by Insulin-like Growth Factor I (IGF-I) Involves Preserved AKT (Protein Kinase B) Activity. J Biol Chem 2015; 291:2510-23. [PMID: 26631726 DOI: 10.1074/jbc.m115.695478] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Indexed: 12/16/2022] Open
Abstract
Disruption of insulin-like growth factor I (IGF-I) signaling is a key step in the development of cancer or neurodegeneration. For example, interference of the prosurvival IGF-I/AKT/FOXO3 pathway by redox activation of the stress kinases p38 and JNK is instrumental in neuronal death by oxidative stress. However, in astrocytes, IGF-I retains its protective action against oxidative stress. The molecular mechanisms underlying this cell-specific protection remain obscure but may be relevant to unveil new ways to combat IGF-I/insulin resistance. Here, we describe that, in astrocytes exposed to oxidative stress by hydrogen peroxide (H2O2), p38 activation did not inhibit AKT (protein kinase B) activation by IGF-I, which is in contrast to our previous observations in neurons. Rather, stimulation of AKT by IGF-I was significantly higher and more sustained in astrocytes than in neurons either under normal or oxidative conditions. This may be explained by phosphorylation of the phosphatase PTEN at the plasma membrane in response to IGF-I, inducing its cytosolic translocation and preserving in this way AKT activity. Stimulation of AKT by IGF-I, mimicked also by a constitutively active AKT mutant, reduced oxidative stress levels and cell death in H2O2-exposed astrocytes, boosting their neuroprotective action in co-cultured neurons. These results indicate that armoring of AKT activation by IGF-I is crucial to preserve its cytoprotective effect in astrocytes and may form part of the brain defense mechanism against oxidative stress injury.
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Affiliation(s)
- David Dávila
- From Department Systems Neuroscience, Cajal Institute, Consejo Superior de Investigaciones Científicas (CSIC), and Centro de Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED), Madrid 28002, Spain
| | - Silvia Fernández
- From Department Systems Neuroscience, Cajal Institute, Consejo Superior de Investigaciones Científicas (CSIC), and Centro de Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED), Madrid 28002, Spain
| | - Ignacio Torres-Alemán
- From Department Systems Neuroscience, Cajal Institute, Consejo Superior de Investigaciones Científicas (CSIC), and Centro de Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED), Madrid 28002, Spain
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Role and Importance of IGF-1 in Traumatic Brain Injuries. BIOMED RESEARCH INTERNATIONAL 2015; 2015:736104. [PMID: 26417600 PMCID: PMC4568328 DOI: 10.1155/2015/736104] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 12/24/2014] [Indexed: 01/02/2023]
Abstract
It is increasingly affirmed that most of the long-term consequences of TBI are due to molecular and cellular changes occurring during the acute phase of the injury and which may, afterwards, persist or progress. Understanding how to prevent secondary damage and improve outcome in trauma patients, has been always a target of scientific interest. Plans of studies focused their attention on the posttraumatic neuroendocrine dysfunction in order to achieve a correlation between hormone blood level and TBI outcomes. The somatotropic axis (GH and IGF-1) seems to be the most affected, with different alterations between the acute and late phases. IGF-1 plays an important role in brain growth and development, and it is related to repair responses to damage for both the central and peripheral nervous system. The IGF-1 blood levels result prone to decrease during both the early and late phases after TBI. Despite this, experimental studies on animals have shown that the CNS responds to the injury upregulating the expression of IGF-1; thus it appears to be related to the secondary mechanisms of response to posttraumatic damage. We review the mechanisms involving IGF-1 in TBI, analyzing how its expression and metabolism may affect prognosis and outcome in head trauma patients.
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Abstract
Several studies have indicated that Diabetes Mellitus (DM) can increase the risk
of developing Alzheimer's disease (AD). This review briefly describes current
concepts in mechanisms linking DM and insulin resistance/deficiency to AD.
Insulin/insulin-like growth factor (IGF) resistance can contribute to
neurodegeneration by several mechanisms which involve: energy and metabolism
deficits, impairment of Glucose transporter-4 function, oxidative and
endoplasmic reticulum stress, mitochondrial dysfunction, accumulation of AGEs,
ROS and RNS with increased production of neuro-inflammation and activation of
pro-apoptosis cascade. Impairment in insulin receptor function and increased
expression and activation of insulin-degrading enzyme (IDE) have also been
described. These processes compromise neuronal and glial function, with a
reduction in neurotransmitter homeostasis. Insulin/IGF resistance causes the
accumulation of AβPP-Aβ oligomeric fibrils or insoluble larger
aggregated fibrils in the form of plaques that are neurotoxic. Additionally,
there is production and accumulation of hyper-phosphorylated insoluble fibrillar
tau which can exacerbate cytoskeletal collapse and synaptic disconnection.
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Affiliation(s)
- Maria Niures P S Matioli
- Pós-graduanda, nível de Doutorado, Departamento de Neurologia da Faculdade de Medicina da Universidade de São Paulo
| | - Ricardo Nitrini
- Professor Titular da Disciplina de Neurologia da Faculdade de Medicina da Universidade de São Paulo. Orientador e Professor Responsável pela Pós-graduação do Departamento de Neurologia da Faculdade de Medicina da Universidade de São Paulo
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Gu J, Liu H, Zhang N, Tian H, Pan J, Zhang W, Wang J. Effect of transgenic human insulin-like growth factor-1 on spinal motor neurons following peripheral nerve injury. Exp Ther Med 2015; 10:19-24. [PMID: 26170906 DOI: 10.3892/etm.2015.2472] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Accepted: 02/03/2015] [Indexed: 01/31/2023] Open
Abstract
The aim of the present study was to observe the protective effect of exogenous human insulin-like growth factor-1 (hIGF-1) on spinal motor neurons, following its local transfection into an area of peripheral nerve injury. A total of 90 male Wistar rats that had been established as sciatic nerve crush injury models were randomly divided into three groups: hIGF-1 treatment, sham-transfected control and blank control groups. The different phases of hIGF-1 expression were observed in the spinal cord via postoperative immunostaining and the apoptosis of motor neurons was observed using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling method. Pathological changes of the motor neurons and Nissl bodies within cell bodies were observed via Marsland and Luxol fast blue double staining, while changes in the neuropil of the spinal cord anterior horn were investigated via ultrastructural observation. It was found that hIGF-1, locally transfected into an area of peripheral nerve injury, was expressed in the spinal anterior horn following axoplasmic transport; the peak hIGF-1 expression occurred approximately a week following transfection. The number of apoptotic spinal cord motor neurons observed in the hIGF-1 treatment group was fewer than that in the sham-transfected and blank control groups at days 7, 14 and 21 following transfection (P<0.01). Furthermore, the quantity of motor neuron cells in the anterior horn of the spinal cord in the hIGF-1 treatment group was higher compared with those in the sham-transfected and blank control groups at days 2, 7, 14 and 28 following transfection (P<0.01). The degenerative changes of Nissl bodies within the cytoplasm of the hIGF-1 treatment group were less severe compared with those of the sham-transfected and blank control groups. At day 56 following transfection, the spinal anterior horn neuropil ultrastructure in the hIGF-1 treatment group was generally normal, while the sham-transfected and blank control groups exhibited an increased number of protruding gaps and local cavities. These results indicate that the application of exogenous hIGF-1 is capable of protecting spinal cord motor neurons following peripheral nerve injury.
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Affiliation(s)
- Jiaxiang Gu
- Department of Hand Surgery, Clinical Medical Institute of Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| | - Hongjun Liu
- Department of Hand Surgery, Clinical Medical Institute of Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| | - Naichen Zhang
- Department of Hand Surgery, Clinical Medical Institute of Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| | - Heng Tian
- Department of Hand Surgery, Clinical Medical Institute of Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| | - Junbo Pan
- Department of Hand Surgery, Clinical Medical Institute of Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| | - Wenzhong Zhang
- Department of Hand Surgery, Clinical Medical Institute of Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| | - Jingcheng Wang
- Department of Hand Surgery, Clinical Medical Institute of Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
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Hu W, Li T, Wu L, Li M, Meng X. Identification of microRNA-18a as a novel regulator of the insulin-like growth factor-1 in the proliferation and regeneration of deer antler. Biotechnol Lett 2014; 36:703-10. [PMID: 24563285 DOI: 10.1007/s10529-013-1428-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Accepted: 12/09/2013] [Indexed: 01/10/2023]
Abstract
To investigate the effect of miR-18a on the regulation of the insulin-like growth factor (IGF-1) during growth of antlers in sika deer, miRNA Chip analysis, Target Scan and real-time PCR analysis were used to identify miRNAs that bind to the 3'-UTR of IGF-1. An miR-18a mimic was transfected into antler cartilage cells and the expression levels were quantified by real-time PCR. Dual luciferase assays revealed that miR-18a binds to the 3'-UTR of the IGF-1 gene thus indicating this to be a target gene regulated by miR-18a. MTT assays and cell-cycle analyses confirmed that miR-18a significantly inhibited proliferation of cartilage cells. In contrast, transfection of miR-18a inhibitors increased proliferation. Furthermore, Western blot analysis showed that over-expression of miR-18a down-regulated IGF-1 protein levels while IGF-1 expression was increased after transfection of miR-18a inhibitors. Thus, miR-1 down-regulated IGF-1 expression thus implicating miR-18a as an important regulator of antler proliferation.
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Affiliation(s)
- Wei Hu
- College of Life Sciences, Jilin Agriculture University, Changchun, 130118, Jilin, China,
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Madathil SK, Carlson SW, Brelsfoard JM, Ye P, D’Ercole AJ, Saatman KE. Astrocyte-Specific Overexpression of Insulin-Like Growth Factor-1 Protects Hippocampal Neurons and Reduces Behavioral Deficits following Traumatic Brain Injury in Mice. PLoS One 2013; 8:e67204. [PMID: 23826235 PMCID: PMC3695083 DOI: 10.1371/journal.pone.0067204] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 05/16/2013] [Indexed: 11/19/2022] Open
Abstract
Traumatic brain injury (TBI) survivors often suffer from long-lasting cognitive impairment that stems from hippocampal injury. Systemic administration of insulin-like growth factor-1 (IGF-1), a polypeptide growth factor known to play vital roles in neuronal survival, has been shown to attenuate posttraumatic cognitive and motor dysfunction. However, its neuroprotective effects in TBI have not been examined. To this end, moderate or severe contusion brain injury was induced in mice with conditional (postnatal) overexpression of IGF-1 using the controlled cortical impact (CCI) injury model. CCI brain injury produces robust reactive astrocytosis in regions of neuronal damage such as the hippocampus. We exploited this regional astrocytosis by linking expression of hIGF-1 to the astrocyte-specific glial fibrillary acidic protein (GFAP) promoter, effectively targeting IGF-1 delivery to vulnerable neurons. Following brain injury, IGF-1Tg mice exhibited a progressive increase in hippocampal IGF-1 levels which was coupled with enhanced hippocampal reactive astrocytosis and significantly greater GFAP levels relative to WT mice. IGF-1 overexpression stimulated Akt phosphorylation and reduced acute (1 and 3d) hippocampal neurodegeneration, culminating in greater neuron survival at 10d after CCI injury. Hippocampal neuroprotection achieved by IGF-1 overexpression was accompanied by improved motor and cognitive function in brain-injured mice. These data provide strong support for the therapeutic efficacy of increased brain levels of IGF-1 in the setting of TBI.
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Affiliation(s)
- Sindhu K. Madathil
- Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, Kentucky, United States of America
| | - Shaun W. Carlson
- Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, Kentucky, United States of America
| | - Jennifer M. Brelsfoard
- Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, Kentucky, United States of America
| | - Ping Ye
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - A. Joseph D’Ercole
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Kathryn E. Saatman
- Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, Kentucky, United States of America
- * E-mail:
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Miki T, Lee KY, Yokoyama T, Liu JQ, Kusaka T, Suzuki S, Ohta KI, Warita K, Jamal M, Ueki M, Yakura T, Hosomi N, Takeuchi Y. Differential effects of neonatal maternal separation on the expression of neurotrophic factors in rat brain. II: Regional differences in the cerebellum versus the cerebral cortex. Okajimas Folia Anat Jpn 2013; 90:53-8. [PMID: 24670490 DOI: 10.2535/ofaj.90] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
This study was conducted in order to examine the effects of early postnatal maternal separation stress on the age-dependent fluctuations in the expression levels of neurotrophic factor ligands and receptors in the developing cerebellum. Wistar rats were separated from their mothers for 3 h each day during postnatal days (PND) 10 to 15. The expression level of mRNA for brain-derived neurotrophic factor (BDNF), tyrosine kinase receptor B (TrkB), insulin-like growth factor-1 (IGF-1), and type-1 IGF receptor (IGF-1R) were evaluated in the cerebellum on PND16, 20, 30, and 60 with real-time RT-PCR. The mRNA levels of cerebellar BDNF in maternally separated rats were increased on PND16, while the other variables showed no significant alterations at any of the time points examined. However, the effects of an identical maternal separation on the cerebral cortex were previously reported to be completely different. These results indicate regional differences in the responses of neurotrophic factor ligands/receptors between the cerebellum and cerebral cortex. Given that neurotrophic factors play important roles in brain development, alterations in these factors may interrupt normal brain development and ultimately, lead to functional disruptions.
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Affiliation(s)
- Takanori Miki
- Departments of Anatomy and Neurobiology, Kagawa University
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GIT2 acts as a potential keystone protein in functional hypothalamic networks associated with age-related phenotypic changes in rats. PLoS One 2012; 7:e36975. [PMID: 22606319 PMCID: PMC3351446 DOI: 10.1371/journal.pone.0036975] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Accepted: 04/10/2012] [Indexed: 01/08/2023] Open
Abstract
The aging process affects every tissue in the body and represents one of the most complicated and highly integrated inevitable physiological entities. The maintenance of good health during the aging process likely relies upon the coherent regulation of hormonal and neuronal communication between the central nervous system and the periphery. Evidence has demonstrated that the optimal regulation of energy usage in both these systems facilitates healthy aging. However, the proteomic effects of aging in regions of the brain vital for integrating energy balance and neuronal activity are not well understood. The hypothalamus is one of the main structures in the body responsible for sustaining an efficient interaction between energy balance and neurological activity. Therefore, a greater understanding of the effects of aging in the hypothalamus may reveal important aspects of overall organismal aging and may potentially reveal the most crucial protein factors supporting this vital signaling integration. In this study, we examined alterations in protein expression in the hypothalami of young, middle-aged, and old rats. Using novel combinatorial bioinformatics analyses, we were able to gain a better understanding of the proteomic and phenotypic changes that occur during the aging process and have potentially identified the G protein-coupled receptor/cytoskeletal-associated protein GIT2 as a vital integrator and modulator of the normal aging process.
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35
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Ma X, Hamadeh MJ, Christie BR, Foster JA, Tarnopolsky MA. Impact of treadmill running and sex on hippocampal neurogenesis in the mouse model of amyotrophic lateral sclerosis. PLoS One 2012; 7:e36048. [PMID: 22558322 PMCID: PMC3338488 DOI: 10.1371/journal.pone.0036048] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Accepted: 03/27/2012] [Indexed: 12/30/2022] Open
Abstract
Hippocampal neurogenesis in the subgranular zone (SGZ) of dentate gyrus (DG) occurs throughout life and is regulated by pathological and physiological processes. The role of oxidative stress in hippocampal neurogenesis and its response to exercise or neurodegenerative diseases remains controversial. The present study was designed to investigate the impact of oxidative stress, treadmill exercise and sex on hippocampal neurogenesis in a murine model of heightened oxidative stress (G93A mice). G93A and wild type (WT) mice were randomized to a treadmill running (EX) or a sedentary (SED) group for 1 or 4 wk. Immunohistochemistry was used to detect bromodeoxyuridine (BrdU) labeled proliferating cells, surviving cells, and their phenotype, as well as for determination of oxidative stress (3-NT; 8-OHdG). BDNF and IGF1 mRNA expression was assessed by in situ hybridization. Results showed that: (1) G93A-SED mice had greater hippocampal neurogenesis, BDNF mRNA, and 3-NT, as compared to WT-SED mice. (2) Treadmill running promoted hippocampal neurogenesis and BDNF mRNA content and lowered DNA oxidative damage (8-OHdG) in WT mice. (3) Male G93A mice showed significantly higher cell proliferation but a lower level of survival vs. female G93A mice. We conclude that G93A mice show higher hippocampal neurogenesis, in association with higher BDNF expression, yet running did not further enhance these phenomena in G93A mice, probably due to a 'ceiling effect' of an already heightened basal levels of hippocampal neurogenesis and BDNF expression.
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Affiliation(s)
- Xiaoxing Ma
- Medical Sciences, McMaster University, Hamilton, Canada
- Department of Medicine, McMaster University, Hamilton, Canada
| | - Mazen J. Hamadeh
- Department of Pediatrics, McMaster University, Hamilton, Canada
- Kinesiology and Health Science, York University, Toronto, Canada
| | | | - Jane A. Foster
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Brain-Body Institute, St. Joseph's Healthcare, Hamilton, Ontario, Canada
| | - Mark A. Tarnopolsky
- Medical Sciences, McMaster University, Hamilton, Canada
- Department of Medicine, McMaster University, Hamilton, Canada
- Department of Pediatrics, McMaster University, Hamilton, Canada
- * E-mail:
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Wen Q, Wang H, Little PJ, Quirion R, Zheng W. Forkhead family transcription factor FoxO and neural differentiation. Neurogenetics 2012; 13:105-13. [PMID: 22453702 DOI: 10.1007/s10048-012-0320-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 03/05/2012] [Indexed: 12/24/2022]
Abstract
The Forkhead Box subgroup O (FoxO) transcription factor family is one of the most important downstream targets of the phosphatidylinositol 3-kinase/protein kinase B signaling pathway playing an important role in many biological functions including transcriptional regulation of cellular differentiation. Neuronal differentiation is a complex process which involves many signaling pathways and molecular mechanisms. Interestingly, recent studies indicate that the FoxO family is involved in a number of signaling pathways regulating cell differentiation. The actions occur at different stages in the differentiation process and by differing mechanisms. This review will focus on FoxO as a novel transcription factor in neural differentiation.
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Affiliation(s)
- Qiang Wen
- Neuropharmacology, School of Pharmaceutical Sciences, Sun Yat-sen University, Higher Education Mega Center, Guangzhou 510006, Guangdong, People's Republic of China
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de la Monte SM. Contributions of brain insulin resistance and deficiency in amyloid-related neurodegeneration in Alzheimer's disease. Drugs 2012; 72:49-66. [PMID: 22191795 PMCID: PMC4550303 DOI: 10.2165/11597760-000000000-00000] [Citation(s) in RCA: 173] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Alzheimer's disease (AD) is the most common cause of dementia in North America. Growing evidence supports the concept that AD is fundamentally a metabolic disease that results in progressive impairment in the brain's capacity to utilize glucose and respond to insulin and insulin-like growth factor (IGF) stimulation. Moreover, the heterogeneous nature of AD is only partly explained by the brain's propensity to accumulate aberrantly processed, misfolded and aggregated oligomeric structural proteins, including amyloid-β peptides and hyperphosphorylated tau. Evidence suggests that other factors, including impaired energy metabolism, oxidative stress, neuroinflammation, insulin and IGF resistance, and insulin/IGF deficiency in the brain should be incorporated into an overarching hypothesis to develop more realistic diagnostic and therapeutic approaches to AD. In this review, the interrelationship between impaired insulin and IGF signalling and amyloid-β pathology is discussed along with potential therapeutic approaches. Impairments in brain insulin/IGF signalling lead to increased expression of amyloid-β precursor protein (AβPP) and accumulation of AβPP-Aβ. In addition, they promote oxidative stress and deficits in energy metabolism, leading to the activation of pro-AβPP-Aβ-mediated neurodegeneration cascades. Although brain insulin/IGF resistance and deficiency can be induced by primary or secondary disease processes, the soaring rates of peripheral insulin resistance associated with obesity, diabetes mellitus and metabolic syndrome quite likely play major roles in the current AD epidemic. Both clinical and experimental data have linked chronic hyperinsulinaemia to cognitive impairment and neurodegeneration with increased AβPP-Aβ accumulation/reduced clearance in the CNS. Correspondingly, both the restoration of insulin responsiveness and the use of insulin therapy can lead to improved cognitive performance, although with variable effects on brain AβPP-Aβ load. On the other hand, experimental evidence supports the concept that the toxic effects of AβPP-Aβ can promote insulin resistance. Together, these findings suggest that a positive feedback loop of progressive neurodegeneration can develop whereby insulin resistance drives AβPP-Aβ accumulation, and AβPP-Aβ fibril toxicity drives brain insulin resistance. This phenomenon could explain why measuring AβPP-Aβ levels in cerebrospinal fluid or imaging of the brain has proven to be inadequate as a stand-alone biomarker for diagnosing AD, and why the clinical trial results of anti-AβPP-Aβ monotherapy have been disappointing. Instead, the aggregate data suggest that brain insulin resistance and deficiency must also be therapeutically targeted to halt AD progression or reverse its natural course. The positive therapeutic effects of different treatments that address the role of brain insulin/IGF resistance and deficiency, including the use of intranasal insulin delivery, incretins and insulin sensitizer agents are discussed along with potential benefits of lifestyle changes to modify risk for developing mild cognitive impairment or AD. Altogether, the data strongly support the notion that we must shift toward the implementation of multimodal rather than unimodal diagnostic and therapeutic strategies for AD.
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Affiliation(s)
- Suzanne M de la Monte
- Department of Pathology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI 02903, USA.
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38
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de la Monte SM. Therapeutic targets of brain insulin resistance in sporadic Alzheimer's disease. Front Biosci (Elite Ed) 2012. [PMID: 22201977 DOI: 10.2741/482] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Growing evidence supports roles for brain insulin and insulin-like growth factor (IGF) resistance and metabolic dysfunction in the pathogenesis of Alzheimer's disease (AD). Whether the underlying problem stems from a primary disorder of central nervous system (CNS) neurons and glia, or secondary effects of systemic diseases such as obesity, Type 2 diabetes, or metabolic syndrome, the end-results include impaired glucose utilization, mitochondrial dysfunction, increased oxidative stress, neuroinflammation, and the propagation of cascades that result in the accumulation of neurotoxic misfolded, aggregated, and ubiquitinated fibrillar proteins. This article reviews the roles of impaired insulin and IGF signaling to AD-associated neuronal loss, synaptic disconnection, tau hyperphosphorylation, amyloid-beta accumulation, and impaired energy metabolism, and discusses therapeutic strategies and lifestyle approaches that could be used to prevent, delay the onset, or reduce the severity of AD. Finally, it is critical to recognize that AD is heterogeneous and has a clinical course that fully develops over a period of several decades. Therefore, early and multi-modal preventive and treatment approaches should be regarded as essential.
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Affiliation(s)
- Suzanne M de la Monte
- Department of Neurology, Rhode Island Hospital and Alpert Medical School of Brown University, Providence, RI, USA.
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Akundi RS, Zhi L, Büeler H. PINK1 enhances insulin-like growth factor-1-dependent Akt signaling and protection against apoptosis. Neurobiol Dis 2011; 45:469-78. [PMID: 21945539 DOI: 10.1016/j.nbd.2011.08.034] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 08/23/2011] [Accepted: 08/26/2011] [Indexed: 12/13/2022] Open
Abstract
Mutations in the PARK6 gene coding for PTEN-induced kinase 1 (PINK1) cause recessive early-onset Parkinsonism. Although PINK1 and Parkin promote the degradation of depolarized mitochondria in cultured cells, little is known about changes in signaling pathways that may additionally contribute to dopamine neuron loss in recessive Parkinsonism. Accumulating evidence implicates impaired Akt cell survival signaling in sporadic and familial PD (PD). IGF-1/Akt signaling inhibits dopamine neuron loss in several animal models of PD and both IGF-1 and insulin are neuroprotective in various settings. Here, we tested whether PINK1 is required for insulin-like growth factor 1 (IGF-1) and insulin dependent phosphorylation of Akt and the regulation of downstream Akt target proteins. Our results show that embryonic fibroblasts from PINK1-deficient mice display significantly reduced Akt phosphorylation in response to both IGF-1 and insulin. Moreover, phosphorylation of glycogen synthase kinase-3β (GSK-3β) and nuclear exclusion of FoxO1 are decreased in IGF-1 treated PINK1-deficient cells. In addition, phosphorylation of ribosomal protein S6 is reduced indicating decreased activity of mitochondrial target of rapamycin (mTOR) in IGF-1 treated PINK1(-/-) cells. Importantly, the protection afforded by IGF-1 against staurosporine-induced metabolic dysfunction and apoptosis is abrogated in PINK1-deficient cells. Moreover, IGF-1-induced Akt phosphorylation is impaired in primary cortical neurons from PINK1-deficient mice. Inhibition of cellular Ser/Thr phosphatases did not increase the amount of phosphorylated Akt in PINK1(-/-) cells, suggesting that components upstream of Akt phosphorylation are compromised in PINK1-deficient cells. Our studies show that PINK1 is required for optimal IGF-1 and insulin dependent Akt signal transduction, and raise the possibility that impaired IGF-1/Akt signaling is involved in PINK1-related Parkinsonism by increasing the vulnerability of dopaminergic neurons to stress-induced cell death.
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Affiliation(s)
- Ravi S Akundi
- Department of Anatomy and Neurobiology, University of Kentucky, 800 Rose Street, Lexington, KY 40536, USA
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Marwarha G, Prasanthi JR, Schommer J, Dasari B, Ghribi O. Molecular interplay between leptin, insulin-like growth factor-1, and β-amyloid in organotypic slices from rabbit hippocampus. Mol Neurodegener 2011; 6:41. [PMID: 21651786 PMCID: PMC3121598 DOI: 10.1186/1750-1326-6-41] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Accepted: 06/08/2011] [Indexed: 01/22/2023] Open
Abstract
Background Evidence shows that the insulin-like growth factor-1 (IGF-1) and leptin reduce β-amyloid (Aβ) production and tau phosphorylation, two major hallmarks of Alzheimer's disease (AD). IGF-1 expression involves the JAK/STAT pathway and the expression of leptin is regulated by the mammalian target of rapamycin complex 1 (mTORC1). We have previously shown that Aβ reduces leptin by inhibiting the mTORC1 pathway and Aβ was also suggested to inhibit the JAK/STAT pathway, potentially attenuating IGF-1 expression. As IGF-1 can activate mTORC1 and leptin can modulate JAK/STAT pathway, we determined the extent to which IGF-1 and leptin can upregulate the expression of one another and protect against Aβ-induced downregulation. Results We demonstrate that incubation of organotypic slices from adult rabbit hippocampus with Aβ42 downregulates IGF-1 expression by inhibiting JAK2/STAT5 pathway. Leptin treatment reverses these Aβ42 effects on IGF-1 and treatment with the STAT5 inhibitor completely abrogated the leptin-induced increase in IGF-1. Furthermore, EMSA and ChIP analyses revealed that leptin increases the STAT5 binding to the IGF-1 promoter. We also show that IGF-1 increases the expression of leptin and reverses the Aβ42-induced attenuation in leptin expression via the activation of mTORC1 signaling as the mTORC1 inhibitor rapamycin completely precluded the IGF-1-induced increase in leptin expression. Conclusion Our results demonstrate for the first time that Aβ42 downregulates IGF-1 expression and that leptin and IGF-1 rescue one another from downregulation by Aβ42. Our study provides a valuable insight into the leptin/IGF-1/Aβ interplay that may be relevant to the pathophysiology of AD.
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Affiliation(s)
- Gurdeep Marwarha
- Department of Pharmacology, Physiology and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota, 58202, USA.
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Li R, Pourpak A, Morris SW. Inhibition of the insulin-like growth factor-1 receptor (IGF1R) tyrosine kinase as a novel cancer therapy approach. J Med Chem 2010; 52:4981-5004. [PMID: 19610618 DOI: 10.1021/jm9002395] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Rongshi Li
- Drug Discovery, H. Lee Moffitt Cancer Center and Research Institute, Oncologic Sciences, University of South Florida, 12902 Magnolia Drive, Tampa, FL 33612, USA.
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Madathil SK, Evans HN, Saatman KE. Temporal and regional changes in IGF-1/IGF-1R signaling in the mouse brain after traumatic brain injury. J Neurotrauma 2010; 27:95-107. [PMID: 19751099 DOI: 10.1089/neu.2009.1002] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Although neurotrophic factors such as nerve growth factor, basic fibroblast growth factor, brain-derived neurotrophic factor, and neurotrophin 4/5 are elevated after traumatic brain injury (TBI), little is known about the endogenous response of insulin-like growth factor-1 (IGF-1). We evaluated IGF-1, IGF-1 receptor (IGF-1R), and total and phosphorylated Akt (p-Akt), a known downstream mediator of IGF-1 signaling, using ELISA, Western blotting, and immunohistochemistry at 1, 6, 24, 48, and 72 h following 0.5-mm controlled cortical impact brain injury in adult mice. IGF-1 was transiently upregulated in homogenates of injured cortex at 1 h, and cells with increased IGF-1 immunoreactivity were observed in and around the cortical contusion site up to 48 h. IGF-1R and total Akt levels in cortical homogenates were unchanged, although immunohistochemistry revealed regional changes. In contrast, serine p-Akt levels increased significantly in homogenates at 6 h post-injury. Interestingly, delayed increases in vascular IGF-1R, total Akt, and p-Akt immunostaining were observed in and around the cortical contusion. IGF-1 and its downstream mediators were also upregulated in the subcortical white matter. Our findings indicate that moderate TBI results in a brief induction of IGF-1 and its signaling components in the acute post-traumatic period. This may reflect an attempt at endogenous neuroprotection or repair.
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Affiliation(s)
- Sindhu Kizhakke Madathil
- Spinal Cord and Brain Injury Research Center, Department of Physiology, University of Kentucky, Lexington, Kentucky 40536-0509, USA
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Abstract
Emerging data demonstrate pivotal roles for brain insulin resistance and insulin deficiency as mediators of cognitive impairment and neurodegeneration, particularly Alzheimer's disease (AD). Insulin and insulin-like growth factors (IGFs) regulate neuronal survival, energy metabolism, and plasticity, which are required for learning and memory. Hence, endogenous brain-specific impairments in insulin and IGF signaling account for the majority of AD-associated abnormalities. However, a second major mechanism of cognitive impairment has been linked to obesity and Type 2 diabetes (T2DM). Human and experimental animal studies revealed that neurodegeneration associated with peripheral insulin resistance is likely effectuated via a liver-brain axis whereby toxic lipids, including ceramides, cross the blood brain barrier and cause brain insulin resistance, oxidative stress, neuro-inflammation, and cell death. In essence, there are dual mechanisms of brain insulin resistance leading to AD-type neurodegeneration: one mediated by endogenous, CNS factors; and the other, peripheral insulin resistance with excess cytotoxic ceramide production.
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Affiliation(s)
- Suzanne M de la Monte
- Department of Neurology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.
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Annenkov A. The insulin-like growth factor (IGF) receptor type 1 (IGF1R) as an essential component of the signalling network regulating neurogenesis. Mol Neurobiol 2009; 40:195-215. [PMID: 19714501 DOI: 10.1007/s12035-009-8081-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2009] [Accepted: 08/14/2009] [Indexed: 02/07/2023]
Abstract
The insulin-like growth factor receptor type 1 (IGF1R) signalling pathway is activated in the mammalian nervous system from early developmental stages. Its major effect on developing neural cells is to promote their growth and survival. This pathway can integrate its action with signalling pathways of growth and morphogenetic factors that induce cell fate specification and selective expansion of specified neural cell subsets. This suggests that during developmental and adult neurogenesis cellular responses to many signalling factors, including ligands of Notch, sonic hedgehog, fibroblast growth factor family members, ligands of the epidermal growth factor receptor, bone morphogenetic proteins and Wingless and Int-1, may be modified by co-activation of the IGF1R. Modulation of cell migration is another possible role that IGF1R activation may play in neurogenesis. Here, I briefly overview neurogenesis and discuss a role for IGF1R-mediated signalling in the developing and mature nervous system with emphasis on crosstalk between the signalling pathways of the IGF1R and other factors regulating neural cell development and migration. Studies on neural as well as on non-neural cells are highlighted because it may be interesting to test in neurogenic paradigms some of the models based on the information obtained in studies on non-neural cell types.
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Affiliation(s)
- Alexander Annenkov
- William Harvey Research Institute, Queen Mary University of London, Charterhouse Square, UK.
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45
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Gamm DM, Wang S, Lu B, Girman S, Holmes T, Bischoff N, Shearer RL, Sauvé Y, Capowski E, Svendsen CN, Lund RD. Protection of visual functions by human neural progenitors in a rat model of retinal disease. PLoS One 2007; 2:e338. [PMID: 17396165 PMCID: PMC1828619 DOI: 10.1371/journal.pone.0000338] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2007] [Accepted: 03/07/2007] [Indexed: 12/17/2022] Open
Abstract
Background A promising clinical application for stem and progenitor cell transplantation is in rescue therapy for degenerative diseases. This strategy seeks to preserve rather than restore host tissue function by taking advantage of unique properties often displayed by these versatile cells. In studies using different neurodegenerative disease models, transplanted human neural progenitor cells (hNPC) protected dying host neurons within both the brain and spinal cord. Based on these reports, we explored the potential of hNPC transplantation to rescue visual function in an animal model of retinal degeneration, the Royal College of Surgeons rat. Methodology/Principal Findings Animals received unilateral subretinal injections of hNPC or medium alone at an age preceding major photoreceptor loss. Principal outcomes were quantified using electroretinography, visual acuity measurements and luminance threshold recordings from the superior colliculus. At 90–100 days postnatal, a time point when untreated rats exhibit little or no retinal or visual function, hNPC-treated eyes retained substantial retinal electrical activity and visual field with near-normal visual acuity. Functional efficacy was further enhanced when hNPC were genetically engineered to secrete glial cell line-derived neurotrophic factor. Histological examination at 150 days postnatal showed hNPC had formed a nearly continuous pigmented layer between the neural retina and retinal pigment epithelium, as well as distributed within the inner retina. A concomitant preservation of host cone photoreceptors was also observed. Conclusions/Significance Wild type and genetically modified human neural progenitor cells survive for prolonged periods, migrate extensively, secrete growth factors and rescue visual functions following subretinal transplantation in the Royal College of Surgeons rat. These results underscore the potential therapeutic utility of hNPC in the treatment of retinal degenerative diseases and suggest potential mechanisms underlying their effect in vivo.
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Affiliation(s)
- David M Gamm
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, Wisconsin, United States of America.
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Sun LY, D'Ercole AJ. Insulin-like growth factor-I stimulates histone H3 and H4 acetylation in the brain in vivo. Endocrinology 2006; 147:5480-90. [PMID: 16935839 PMCID: PMC1847619 DOI: 10.1210/en.2006-0586] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
IGF-I is essential to normal brain growth and exerts actions on neural stem cells and each major neural cell lineage. Whereas many studies show that IGF-I regulates gene expression, mechanisms by which it modulates transcription have not been explored. Chromatin modifications, such as histone phosphorylation, acetylation, and methylation, are known to be important initial steps in gene regulation, and acetylation of histone H3 and H4 is associated with gene activation. In this study, we show that IGF-I modulates the acetylation of H3 and H4 histones in the brain of two transgenic mouse lines and that these effects are associated with activation of the phosphoinositide 3-kinase/Akt signaling pathway. This provides evidence that the chromatin architecture modification contributes to the action of IGF-I on gene expression in the mammalian central nerve system.
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Affiliation(s)
- Liou Y Sun
- Department of Pediatrics, Division of Endocrinology, Campus Box 7039, 3341 MBRB, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7039, USA
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Alberghina L, Colangelo AM. The modular systems biology approach to investigate the control of apoptosis in Alzheimer's disease neurodegeneration. BMC Neurosci 2006; 7 Suppl 1:S2. [PMID: 17118156 PMCID: PMC1775042 DOI: 10.1186/1471-2202-7-s1-s2] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Apoptosis is a programmed cell death that plays a critical role during the development of the nervous system and in many chronic neurodegenerative diseases, including Alzheimer's disease (AD). This pathology, characterized by a progressive degeneration of cholinergic function resulting in a remarkable cognitive decline, is the most common form of dementia with high social and economic impact. Current therapies of AD are only symptomatic, therefore the need to elucidate the mechanisms underlying the onset and progression of the disease is surely needed in order to develop effective pharmacological therapies. Because of its pivotal role in neuronal cell death, apoptosis has been considered one of the most appealing therapeutic targets, however, due to the complexity of the molecular mechanisms involving the various triggering events and the many signaling cascades leading to cell death, a comprehensive understanding of this process is still lacking. Modular systems biology is a very effective strategy in organizing information about complex biological processes and deriving modular and mathematical models that greatly simplify the identification of key steps of a given process. This review aims at describing the main steps underlying the strategy of modular systems biology and briefly summarizes how this approach has been successfully applied for cell cycle studies. Moreover, after giving an overview of the many molecular mechanisms underlying apoptosis in AD, we present both a modular and a molecular model of neuronal apoptosis that suggest new insights on neuroprotection for this disease.
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Affiliation(s)
- Lilia Alberghina
- Department of Biotechnology and Biosciences, Laboratory of Neuroscience R. Levi-Montalcini, University of Milano-Bicocca, 20126 Milan, Italy.
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Bluthé RM, Kelley KW, Dantzer R. Effects of insulin-like growth factor-I on cytokine-induced sickness behavior in mice. Brain Behav Immun 2006; 20:57-63. [PMID: 16364817 PMCID: PMC2907139 DOI: 10.1016/j.bbi.2005.02.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2005] [Accepted: 02/28/2005] [Indexed: 10/25/2022] Open
Abstract
Central administration of insulin-like growth factor-I (IGF-I) attenuates sickness behavior in response to the cytokine inducer lipopolysaccharide. The present study was designed to determine the respective roles of the two main proinflammatory cytokines, tumor necrosis factor alpha (TNFalpha) and interleukin-1beta (IL-1beta), in these effects. Male CD1 mice were injected into the lateral ventricle (i.c.v.) of the brain with optimal amounts of either TNFalpha (50 ng) or IL-1beta (2 ng) that induce sickness behavior. Behavioral responses to IGF-I (0, .1, and 1 microg) also given i.c.v. were measured at various time intervals before and after treatment with the two proinflammatory cytokines. Mice treated with TNFalpha and IL-1beta lost body weight and displayed equivalent reductions in social exploration and instances of immobility. At the dose of .1 microg, IGF-I attenuated these signs of sickness in TNFalpha-but not in IL-1beta-treated mice. At the dose of 1 microg, IGF-I attenuated IL-1beta-induced immobility and the reduction in social exploration but had no effect on loss of body weight. These findings indicate that IGF-I is more potent in attenuating sickness behavior induced by TNFalpha than that caused by IL-1beta, which is consistent with the relative specificity of the TNFalpha/IGF-I interactions in the brain.
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Affiliation(s)
- Rose-Marie Bluthé
- Integrative Neurobiology, CNRS-INRA-University Victor Segalen, Bordeaux, France.
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Bi X, Liu J, Yao Y, Baudry M, Lynch G. Deregulation of the phosphatidylinositol-3 kinase signaling cascade is associated with neurodegeneration in Npc1-/- mouse brain. THE AMERICAN JOURNAL OF PATHOLOGY 2005; 167:1081-92. [PMID: 16192643 PMCID: PMC1603683 DOI: 10.1016/s0002-9440(10)61197-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Niemann-Pick type C (NPC) disease is caused by mutations to genes that encode proteins critical to intracellular lipid homeostasis. The events underlying NPC progressive neurodegeneration are poorly understood but include neurofibrillary tangles of the type found in Alzheimer's disease. Here we investigated possible contributions of a phosphatidylinositol-3 kinase cascade [PI3K, Akt, glycogen synthase kinase-3beta (GSK-3beta)] that is linked to apoptosis and various degenerative conditions. Brain concentrations of phosphorylated Akt, which phosphorylates and inactivates GSK-3beta, were significantly elevated in Npc1-/- mice relative to Npc1+/+ mice. Accordingly, levels of inactive GSK-3beta were 50 to 100% higher in mutant brains than in controls. Increases in inactive GSK-3beta occurred early in postnatal development, well before neuronal loss, and were most prominent in structures with intracellular cholesterol accumulation, suggesting a contribution to subsequent degeneration. Perturbations of nuclear factor (NF)-kappaB, which is regulated by GSK-3beta, occurred in Npc1-/- mouse brains. Nuclear concentrations and DNA binding activity of NF-kappaB's transactivation subunit, p65, were significantly reduced in Npc1-/- mice compared to Npc1+/+ mice. Cytoplasmic levels of the p50 subunit and its precursor, p105, were higher in Npc1-/- mice. These results suggest that excessive activity in the PI3K-Akt pathway depresses GSK-3beta, thereby disrupting the formation and/or nuclear import of p50/p65 NF-kappaB dimers and contributing to neuronal degeneration.
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Affiliation(s)
- Xiaoning Bi
- Department of Psychiatry and Human Behavior, 101 Theory Dr., UC Irvine, Irvine, CA 92617, USA.
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Frago LM, Cañón S, de la Rosa EJ, León Y, Varela-Nieto I. Programmed cell death in the developing inner ear is balanced by nerve growth factor and insulin-like growth factor I. J Cell Sci 2003; 116:475-86. [PMID: 12508109 DOI: 10.1242/jcs.00223] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nerve growth factor induces cell death in organotypic cultures of otic vesicle explants. This cell death has a restricted pattern that reproduces the in vivo pattern of apoptosis occurring during inner ear development. In this study, we show that binding of nerve growth factor to its low affinity p75 neurotrophin receptor is essential to achieve the apoptotic response. Blockage of binding to p75 receptor neutralized nerve-growth-factor-induced cell death, as measured by immunoassays detecting the presence of cytosolic oligonucleosomes and by TUNEL assay to visualize DNA fragmentation. Nerve growth factor also induced a number of cell-death-related intracellular events including ceramide generation, caspase activation and poly-(ADP ribose) polymerase cleavage. Again, p75 receptor blockade completely abolished all of these effects. Concerning the intracellular pathway, ceramide increase depended on initiator caspases, whereas its actions depended on both initiator and effector caspases, as shown by using site-specific caspase inhibitors. Conversely, insulin-like growth factor I, which promotes cell growth and survival in the inner ear, abolished apoptosis induced by nerve growth factor. Insulin-like growth factor cytoprotective actions were accomplished, at least in part, by decreasing endogenous ceramide levels and activating Akt. Taken together, these results strongly suggest that regulation of nerve-growth-factor-induced apoptosis in the otocysts occurs via p75 receptor binding and is strictly controlled by the interaction with survival signalling pathways.
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Affiliation(s)
- Laura M Frago
- Instituto de Investigaciones Biomédicas "Alberto Sols", Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Arturo Duperier 4, 28029 Madrid, Spain
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