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Sullere S, Kunczt A, McGehee DS. A cholinergic circuit that relieves pain despite opioid tolerance. Neuron 2023; 111:3414-3434.e15. [PMID: 37734381 PMCID: PMC10843525 DOI: 10.1016/j.neuron.2023.08.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 04/19/2023] [Accepted: 08/16/2023] [Indexed: 09/23/2023]
Abstract
Chronic pain is a tremendous burden for afflicted individuals and society. Although opioids effectively relieve pain, significant adverse outcomes limit their utility and efficacy. To investigate alternate pain control mechanisms, we explored cholinergic signaling in the ventrolateral periaqueductal gray (vlPAG), a critical nexus for descending pain modulation. Biosensor assays revealed that pain states decreased acetylcholine release in vlPAG. Activation of cholinergic projections from the pedunculopontine tegmentum to vlPAG relieved pain, even in opioid-tolerant conditions, through ⍺7 nicotinic acetylcholine receptors (nAChRs). Activating ⍺7 nAChRs with agonists or stimulating endogenous acetylcholine inhibited vlPAG neuronal activity through Ca2+ and peroxisome proliferator-activated receptor α (PPAR⍺)-dependent signaling. In vivo 2-photon imaging revealed that chronic pain induces aberrant excitability of vlPAG neuronal ensembles and that ⍺7 nAChR-mediated inhibition of these cells relieves pain, even after opioid tolerance. Finally, pain relief through these cholinergic mechanisms was not associated with tolerance, reward, or withdrawal symptoms, highlighting its potential clinical relevance.
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Affiliation(s)
- Shivang Sullere
- Committee on Neurobiology, University of Chicago, Chicago, IL 60637, USA
| | - Alissa Kunczt
- Department of Anesthesia and Critical Care, University of Chicago, Chicago, IL 60637, USA
| | - Daniel S McGehee
- Committee on Neurobiology, University of Chicago, Chicago, IL 60637, USA; Department of Anesthesia and Critical Care, University of Chicago, Chicago, IL 60637, USA.
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Yousefpoor Y, Esnaashari SS, Baharifar H, Mehrabi M, Amani A. Current challenges ahead in preparation, characterization, and pharmaceutical applications of nanoemulsions. WILEY INTERDISCIPLINARY REVIEWS. NANOMEDICINE AND NANOBIOTECHNOLOGY 2023; 15:e1920. [PMID: 37558229 DOI: 10.1002/wnan.1920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 06/07/2023] [Accepted: 06/27/2023] [Indexed: 08/11/2023]
Abstract
Nanoemulsions (NEs) are emulsions with particle size of less than around 100 nm. Reviewing the literature, several reports are available on NEs, including preparation, characterization, and applications of them. This review aims to brief challenges that researchers or formulators may encounter when working with NEs. For instance, when selecting NE components and identifying their concentrations, stability and safety of the preparation should be evaluated. When preparing an NE, issues over scale-up of the preparation as well as possible effects of the preparation process on the active ingredient need to be considered. When characterizing the NEs, the two major concerns are accuracy of the method and accessibility of the characterizing instrument. Also a highly efficient NE for clinical use to deliver the active ingredient to the target tissue with maximum safety profile is commonly sought. Throughout the review we also have tried to suggest approaches to overcome the challenges. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies.
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Affiliation(s)
- Yaser Yousefpoor
- Department of Medical Biotechnology, School of Paramedical Sciences, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran
- Research Center of Advanced Technologies in Medicine, Torbat Heydariyeh University of Medical, Torbat Heydariyeh, Iran
| | - Seyedeh Sara Esnaashari
- Department of Medical Nanotechnology, Faculty of Advanced Sciences and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Hadi Baharifar
- Department of Medical Nanotechnology, Applied Biophotonics Research Center, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Mohsen Mehrabi
- Department of Medical Nanotechnology, School of Medicine, Shahroud University of Medical Sciences, Shahroud, Iran
| | - Amir Amani
- Natural Products and Medicinal Plants Research Center, North Khorasan University of Medical Sciences, Bojnurd, Iran
- Department of Advanced Technologies, School of Medicine, North Khorasan University of Medical Sciences, Bojnurd, Iran
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Ortega JT, Parmar T, Jastrzebska B. Galanin receptor 3 - A new pharmacological target in retina degeneration. Pharmacol Res 2023; 188:106675. [PMID: 36693600 PMCID: PMC9918719 DOI: 10.1016/j.phrs.2023.106675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/16/2023] [Accepted: 01/20/2023] [Indexed: 01/22/2023]
Abstract
The neuropeptide galanin receptor 3 (GALR3) is a class A G protein-coupled receptor (GPCR) broadly expressed in the nervous system, including the retina. GALR3 is involved in the modulation of immune and inflammatory responses. Tight control of these processes is critical for maintaining homeostasis in the retina and is required to sustain vision. Here, we investigated the role of GALR3 in retina pathologies triggered by bright light and P23H mutation in the rhodopsin (RHO) gene, associated with the activation of oxidative stress and inflammatory responses. We used a multiphase approach involving pharmacological inhibition of GALR3 with its antagonist SNAP-37889 and genetic depletion of GALR3 to modulate the GALR3 signaling. Our in vitro experiments in the retinal pigment epithelium-derived cells (ARPE19) susceptible to all-trans-retinal toxicity indicated that GALR3 could be involved in the cellular stress response to this phototoxic product. Indeed, blocking the GALR3 signaling in Abca4-/-/Rdh8-/- and wild-type Balb/cJ mice, sensitive to bright light-induced retina damage, protected retina health in these mice exposed to light. The retina morphology and function were substantially improved, and stress response processes were reduced in these mouse models compared to the controls. Furthermore, in P23H Rho knock-in mice, a model of retinitis pigmentosa (RP), both pharmacological inhibition and genetic ablation of GALR3 prolonged the survival of photoreceptors. These results indicate that GALR3 signaling contributes to acute light-induced and chronic RP-linked retinopathies. Together, this work provides the pharmacological knowledge base to evaluate GALR3 as a potential target for developing novel therapies to combat retinal degeneration.
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Affiliation(s)
- Joseph T Ortega
- Department of Pharmacology and Cleveland Center for Membrane and Structural Biology, School of Medicine, Case Western Reserve University, 10900 Euclid Ave., Cleveland, OH 44106, USA
| | - Tanu Parmar
- Department of Pharmacology and Cleveland Center for Membrane and Structural Biology, School of Medicine, Case Western Reserve University, 10900 Euclid Ave., Cleveland, OH 44106, USA
| | - Beata Jastrzebska
- Department of Pharmacology and Cleveland Center for Membrane and Structural Biology, School of Medicine, Case Western Reserve University, 10900 Euclid Ave., Cleveland, OH 44106, USA.
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Reinstatement of synaptic plasticity in the aging brain through specific dopamine transporter inhibition. Mol Psychiatry 2021; 26:7076-7090. [PMID: 34244620 DOI: 10.1038/s41380-021-01214-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Aging-related neurological deficits negatively impact mental health, productivity, and social interactions leading to a pronounced socioeconomic burden. Since declining brain dopamine signaling during aging is associated with the onset of neurological impairments, we produced a selective dopamine transporter (DAT) inhibitor to restore endogenous dopamine levels and improve cognitive function. We describe the synthesis and pharmacological profile of (S,S)-CE-158, a highly specific DAT inhibitor, which increases dopamine levels in brain regions associated with cognition. We find both a potentiation of neurotransmission and coincident restoration of dendritic spines in the dorsal hippocampus, indicative of reinstatement of dopamine-induced synaptic plasticity in aging rodents. Treatment with (S,S)-CE-158 significantly improved behavioral flexibility in scopolamine-compromised animals and increased the number of spontaneously active prefrontal cortical neurons, both in young and aging rodents. In addition, (S,S)-CE-158 restored learning and memory recall in aging rats comparable to their young performance in a hippocampus-dependent hole board test. In sum, we present a well-tolerated, highly selective DAT inhibitor that normalizes the age-related decline in cognitive function at a synaptic level through increased dopamine signaling.
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Johnstone MR, Brady RD, Church JE, Orr D, McDonald SJ, Grills BL. The TrkB agonist, 7,8-dihydroxyflavone, impairs fracture healing in mice. JOURNAL OF MUSCULOSKELETAL & NEURONAL INTERACTIONS 2021; 21:263-271. [PMID: 34059571 PMCID: PMC8185262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVES To study the effects of the selective TrkB agonist, 7,8-dihydroxyflavone (7,8-DHF), on fracture healing in mice and on an osteoprogenitor cell line, Kusa4b10, in vitro. METHODS Mice received unilateral closed mid-shaft tibial fractures and treated for two weeks with vehicle or 5 mg/kg/day DHF and euthanised at 28 days post-fracture. Calluses were analysed by micro-computed tomography (μCT) and three-point bending biomechanical test. Kusa4b10 cells were cultured with 50nM of 7,8-DHF or vehicle for 3-, 7-, 14-days for RT-PCR, and 21 days for mineralization. RESULTS μCT found 7,8-DHF calluses had decreased tissue volume (p=0.042), mean polar moment of inertia (p = 0.004), and mean cross-sectional area (p=0.042) compared to controls. At 28 days biomechanical analyses showed 7,8-DHF treatment decreased peak force (p=0.011) and stiffness per unit area (p=0.012). 7,8-DHF treatment did not change Kusa4b10 gene expression of Runx2 and alkaline phosphatase at all time points, nor mineralization. CONCLUSIONS 7,8-DHF treatment had a negative impact on fracture healing at 28 days post-fracture via an unknown mechanism. 7,8-DHF may have had a central role in impairing fracture healing.
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Affiliation(s)
- Maddison R. Johnstone
- Department of Physiology, Anatomy and Microbiology, School of Life Sciences, La Trobe University, Melbourne, Australia
| | - Rhys D. Brady
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Australia
| | - Jarrod E. Church
- Department of Physiology, Anatomy and Microbiology, School of Life Sciences, La Trobe University, Melbourne, Australia
| | - David Orr
- Department of Physiology, Anatomy and Microbiology, School of Life Sciences, La Trobe University, Melbourne, Australia
| | - Stuart J. McDonald
- Department of Physiology, Anatomy and Microbiology, School of Life Sciences, La Trobe University, Melbourne, Australia,Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Australia
| | - Brian L. Grills
- Department of Physiology, Anatomy and Microbiology, School of Life Sciences, La Trobe University, Melbourne, Australia,Corresponding author: Brian L. Grills, Department of Physiology, Anatomy, and Microbiology, School of Life Sciences, La Trobe University, Melbourne, Australia, 3086 E-mail:
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Klymchenko AS, Liu F, Collot M, Anton N. Dye-Loaded Nanoemulsions: Biomimetic Fluorescent Nanocarriers for Bioimaging and Nanomedicine. Adv Healthc Mater 2021; 10:e2001289. [PMID: 33052037 DOI: 10.1002/adhm.202001289] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/21/2020] [Indexed: 12/16/2022]
Abstract
Lipid nanoemulsions (NEs), owing to their controllable size (20 to 500 nm), stability and biocompatibility, are now frequently used in various fields, such as food, cosmetics, pharmaceuticals, drug delivery, and even as nanoreactors for chemical synthesis. Moreover, being composed of components generally recognized as safe (GRAS), they can be considered as "green" nanoparticles that mimic closely lipoproteins and intracellular lipid droplets. Therefore, they attracted attention as carriers of drugs and fluorescent dyes for both bioimaging and studying the fate of nanoemulsions in cells and small animals. In this review, the composition of dye-loaded NEs, methods for their preparation, and emerging biological applications are described. The design of bright fluorescent NEs with high dye loading and minimal aggregation-caused quenching (ACQ) is focused on. Common issues including dye leakage and NEs stability are discussed, highlighting advanced techniques for their characterization, such as Förster resonance energy transfer (FRET) and fluorescence correlation spectroscopy (FCS). Attempts to functionalize NEs surface are also discussed. Thereafter, biological applications for bioimaging and single-particle tracking in cells and small animals as well as biomedical applications for photodynamic therapy are described. Finally, challenges and future perspectives of fluorescent NEs are discussed.
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Affiliation(s)
- Andrey S. Klymchenko
- Laboratory of Biophotonic and Pathologies CNRS UMR 7021 Université de Strasbourg Faculté de Pharmacie, 74, Route du Rhin Illkirch 67401 France
| | - Fei Liu
- Laboratory of Biophotonic and Pathologies CNRS UMR 7021 Université de Strasbourg Faculté de Pharmacie, 74, Route du Rhin Illkirch 67401 France
- Université de Strasbourg CNRS CAMB UMR 7199 Strasbourg F‐67000 France
| | - Mayeul Collot
- Laboratory of Biophotonic and Pathologies CNRS UMR 7021 Université de Strasbourg Faculté de Pharmacie, 74, Route du Rhin Illkirch 67401 France
| | - Nicolas Anton
- Université de Strasbourg CNRS CAMB UMR 7199 Strasbourg F‐67000 France
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Zhou C, Guo C, Li W, Zhao J, Yang Q, Tan T, Wan Z, Dong J, Song X, Gong T. A novel honokiol liposome: formulation, pharmacokinetics, and antitumor studies. Drug Dev Ind Pharm 2018; 44:2005-2012. [PMID: 30058387 DOI: 10.1080/03639045.2018.1506475] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Chuchu Zhou
- Key Laboratory of Drug Targeting and Drug Delivery Systems, Ministry of Education, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China
| | - Chenqi Guo
- Key Laboratory of Drug Targeting and Drug Delivery Systems, Ministry of Education, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China
| | - Wenhao Li
- Key Laboratory of Drug Targeting and Drug Delivery Systems, Ministry of Education, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China
| | - Juan Zhao
- Key Laboratory of Drug Targeting and Drug Delivery Systems, Ministry of Education, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China
| | - Qin Yang
- Key Laboratory of Drug Targeting and Drug Delivery Systems, Ministry of Education, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China
| | - Tiantian Tan
- Key Laboratory of Drug Targeting and Drug Delivery Systems, Ministry of Education, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China
| | - Zhuoya Wan
- School of Pharmacy, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jianxia Dong
- Department of Clinical Pharmacy, West China Hospital of Sichuan University, Chengdu, Sichuan Province, People’s Republic of China
| | - Xu Song
- Key Laboratory of Drug Targeting and Drug Delivery Systems, Ministry of Education, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China
| | - Tao Gong
- Key Laboratory of Drug Targeting and Drug Delivery Systems, Ministry of Education, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China
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Zardad A, Mabrouk M, Marimuthu T, du Toit L, Kumar P, Choonara Y, Kondiah P, Badhe R, Chejara D, Pillay V. Synthesis and biocompatibility of dual-responsive thermosonic injectable organogels based on crosslinked N-(isopropyl acrylamide) for tumour microenvironment targeting. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2018; 90:148-158. [DOI: 10.1016/j.msec.2018.04.059] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 03/28/2018] [Accepted: 04/19/2018] [Indexed: 02/06/2023]
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Jeong SH, Jang JH, Cho HY, Lee YB. Soft- and hard-lipid nanoparticles: a novel approach to lymphatic drug delivery. Arch Pharm Res 2018; 41:797-814. [PMID: 30074202 DOI: 10.1007/s12272-018-1060-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 07/25/2018] [Indexed: 12/31/2022]
Abstract
With the current advance in nanotechnology, the development has accelerated of a number of nanoparticle-type drugs such as nano-emulsions, lipid emulsions, liposomes, and cell therapeutics. With these developments, attempts are being made to apply these new drugs to healing many intractable diseases related to antibody production, autoimmune disorders, cancer, and organ transplantation in both clinical and nonclinical trials. Drug delivery to the lymphatic system is indispensable for treating these diseases, but the core technologies related to the in vivo distribution characteristics and lymphatic delivery evaluation of these particle-type drugs have not yet been established. Additionally, the core technologies for setting up the pharmacotherapeutic aspects such as their usage and dosages in the development of new drugs do not meet the needs of the market. Therefore, it is necessary to consider dividing these particle-type drugs into soft-lipid nanoparticles that can change size in the process of body distribution and hard-lipid nanoparticles whose surfaces are hardened and whose sizes do not easily change in vivo; these soft- and hard-lipid nanoparticles likely possess different biodistribution characteristics including delivery to the lymphatic system. In this review, we summarize the different types, advantages, limitations, possible remedies, and body distribution characteristics of soft- and hard-lipid nanoparticles based on their administration routes. We also emphasize that it will be necessary to fully understand the differences in distribution between these soft- and hard-lipid nanoparticle-type drugs and to establish pharmacokinetic models for their more ideal lymphatic delivery.
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Affiliation(s)
- Seung-Hyun Jeong
- College of Pharmacy, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea
| | - Ji-Hun Jang
- College of Pharmacy, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea
| | - Hea-Young Cho
- College of Pharmacy, CHA University, 335 Pangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-Do, 13488, Republic of Korea
| | - Yong-Bok Lee
- College of Pharmacy, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, Republic of Korea.
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Wilson KE, Limburg S, Duggan MK, Lawther AJ, Williams SJ, Lawrence AJ, Hale MW, Djouma E. The galanin receptor-3 antagonist, SNAP 37889, inhibits cue-induced reinstatement of alcohol-seeking and increases c-Fos expression in the nucleus accumbens shell of alcohol-preferring rats. J Psychopharmacol 2018; 32:911-921. [PMID: 29926762 DOI: 10.1177/0269881118780015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
INTRODUCTION This study aimed to investigate the effects of the galanin-3 receptor antagonist, SNAP 37889, on c-Fos protein expression after cue-induced reinstatement of alcohol-seeking in the brains of alcohol-preferring rats. METHODS Eighteen alcohol-preferring rats were trained to self-administer 10% v/v ethanol in the presence of response-contingent cues, which was followed by extinction. Rats were then treated with SNAP 37889 (30 mg/kg, i.p.) or vehicle, before being tested for cue-induced reinstatement. Administration of SNAP 37889 reduced cue-induced reinstatement of ethanol-seeking behaviour. To examine the effect of SNAP 37889 and cue-induced reinstatement on neuronal activation, c-Fos expression was measured in subregions of the medial prefrontal cortex and nucleus accumbens. RESULTS SNAP 37889 administration increased c-Fos immunoreactivity in the nucleus accumbens shell, but was without effect in the nucleus accumbens core and the medial prefrontal cortex. Dual-label Fos/tyrosine hydroxylase immunohistochemistry was used to examine the effects of SNAP 37889 on dopamine neurons in the ventral tegmental area; however, no differences between SNAP 37889 and vehicle-treated rats were found. CONCLUSIONS These data support previous findings of galanin-3 receptor involvement in cue-induced reinstatement of alcohol-seeking behaviour, and provide novel evidence that the ability of galanin-3 receptor antagonism to attenuate cue-induced reinstatement relates to activation of the nucleus accumbens shell.
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Affiliation(s)
- Kira-Elise Wilson
- 1 School of Psychology and Public Health, La Trobe University, Melbourne, VIC, Australia
| | - Sigrid Limburg
- 1 School of Psychology and Public Health, La Trobe University, Melbourne, VIC, Australia
| | - Melissa K Duggan
- 1 School of Psychology and Public Health, La Trobe University, Melbourne, VIC, Australia
| | - Adam J Lawther
- 1 School of Psychology and Public Health, La Trobe University, Melbourne, VIC, Australia
| | - Spencer J Williams
- 2 School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, VIC, Australia
| | - Andrew J Lawrence
- 3 Florey Institute of Neuroscience and Mental Health, University of Melbourne, VIC, Australia
| | - Matthew W Hale
- 1 School of Psychology and Public Health, La Trobe University, Melbourne, VIC, Australia
| | - Elvan Djouma
- 4 School of Life Sciences, La Trobe University, Melbourne, VIC, Australia
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Johnstone MR, Sun M, Taylor CJ, Brady RD, Grills BL, Church JE, Shultz SR, McDonald SJ. Gambogic amide, a selective TrkA agonist, does not improve outcomes from traumatic brain injury in mice. Brain Inj 2017; 32:257-268. [PMID: 29227174 DOI: 10.1080/02699052.2017.1394492] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVES There is evidence that treatment with nerve growth factor (NGF) may reduce neuroinflammation and apoptosis after a traumatic brain injury (TBI). NGF is thought to exert its effects via binding to either TrkA or p75 neurotrophin receptors. This study aimed to investigate the effects of a selective TrkA agonist, gambogic amide (GA), on TBI pathology and outcomes in mice following lateral fluid percussion injury. METHODS Male C57BL/6 mice were given either a TBI or sham injury, and then received subcutaneous injections of either 2 mg/kg of GA or vehicle at 1, 24, and 48 h post-injury. Following behavioural studies, mice were euthanized at 72 h post-injury for analysis of neuroinflammatory, apoptotic, and neurite outgrowth markers. RESULTS Behavioural testing revealed that GA did not mitigate motor deficits after TBI. TBI caused an increase in cortical and hippocampal expression of several markers of neuroinflammation and apoptosis compared to sham groups. GA treatment did not attenuate these increases in expression, possibly contributed to by our finding of TrkA receptor down-regulation post-TBI. CONCLUSIONS These findings suggest that GA treatment may not be suitable for attenuating TBI pathology and improving outcomes.
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Affiliation(s)
- Maddison R Johnstone
- a Department of Physiology, Anatomy and Microbiology , School of Life Sciences, La Trobe University , Melbourne , VIC , Australia
| | - Mujun Sun
- b Department of Medicine , The Royal Melbourne Hospital, The University of Melbourne , Parkville , VIC , Australia
| | - Caroline J Taylor
- a Department of Physiology, Anatomy and Microbiology , School of Life Sciences, La Trobe University , Melbourne , VIC , Australia
| | - Rhys D Brady
- a Department of Physiology, Anatomy and Microbiology , School of Life Sciences, La Trobe University , Melbourne , VIC , Australia.,b Department of Medicine , The Royal Melbourne Hospital, The University of Melbourne , Parkville , VIC , Australia
| | - Brian L Grills
- a Department of Physiology, Anatomy and Microbiology , School of Life Sciences, La Trobe University , Melbourne , VIC , Australia
| | - Jarrod E Church
- a Department of Physiology, Anatomy and Microbiology , School of Life Sciences, La Trobe University , Melbourne , VIC , Australia
| | - Sandy R Shultz
- b Department of Medicine , The Royal Melbourne Hospital, The University of Melbourne , Parkville , VIC , Australia.,c Department of Neuroscience , Central Clinical School, Monash University , Melbourne , VIC , Australia
| | - Stuart J McDonald
- a Department of Physiology, Anatomy and Microbiology , School of Life Sciences, La Trobe University , Melbourne , VIC , Australia
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Phosphodiesterase 4 inhibition affects both the direct and indirect pathway: an electrophysiological study examining the tri-phasic response in the substantia nigra pars reticulata. Brain Struct Funct 2017; 223:739-748. [DOI: 10.1007/s00429-017-1518-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 09/12/2017] [Indexed: 01/24/2023]
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13
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The galanin-3 receptor antagonist, SNAP 37889, suppresses alcohol drinking and morphine self-administration in mice. Neuropharmacology 2017; 118:1-12. [DOI: 10.1016/j.neuropharm.2017.03.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 02/17/2017] [Accepted: 03/02/2017] [Indexed: 02/07/2023]
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14
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Nanoemulsion: Concepts, development and applications in drug delivery. J Control Release 2017; 252:28-49. [PMID: 28279798 DOI: 10.1016/j.jconrel.2017.03.008] [Citation(s) in RCA: 583] [Impact Index Per Article: 83.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 03/03/2017] [Accepted: 03/04/2017] [Indexed: 01/07/2023]
Abstract
Nanoemulsions are biphasic dispersion of two immiscible liquids: either water in oil (W/O) or oil in water (O/W) droplets stabilized by an amphiphilic surfactant. These come across as ultrafine dispersions whose differential drug loading; viscoelastic as well as visual properties can cater to a wide range of functionalities including drug delivery. However there is still relatively narrow insight regarding development, manufacturing, fabrication and manipulation of nanoemulsions which primarily stems from the fact that conventional aspects of emulsion formation and stabilization only partially apply to nanoemulsions. This general deficiency sets up the premise for current review. We attempt to explore varying intricacies, excipients, manufacturing techniques and their underlying principles, production conditions, structural dynamics, prevalent destabilization mechanisms, and drug delivery applications of nanoemulsions to spike interest of those contemplating a foray in this field.
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