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MacQueen LA, Sheehy SP, Chantre CO, Zimmerman JF, Pasqualini FS, Liu X, Goss JA, Campbell PH, Gonzalez GM, Park SJ, Capulli AK, Ferrier JP, Kosar TF, Mahadevan L, Pu WT, Parker KK. Addendum: A tissue-engineered scale model of the heart ventricle. Nat Biomed Eng 2022; 6:1318. [PMID: 35260798 DOI: 10.1038/s41551-022-00854-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Luke A MacQueen
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Sean P Sheehy
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Christophe O Chantre
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - John F Zimmerman
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Francesco S Pasqualini
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Xujie Liu
- Department of Cardiology, Boston Children's Hospital, Boston, MA, USA
| | - Josue A Goss
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Patrick H Campbell
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Grant M Gonzalez
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Sung-Jin Park
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Andrew K Capulli
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - John P Ferrier
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - T Fettah Kosar
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
| | - L Mahadevan
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
- Kavli Institute for Bionano Science and Technology, Harvard University, Cambridge, MA, USA
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
- Department of Physics, Harvard University, Cambridge, MA, USA
| | - William T Pu
- Department of Cardiology, Boston Children's Hospital, Boston, MA, USA
- Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA
| | - Kevin Kit Parker
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA.
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA.
- Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA.
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Cera L, Gonzalez GM, Liu Q, Choi S, Chantre CO, Lee J, Gabardi R, Choi MC, Shin K, Parker KK. A bioinspired and hierarchically structured shape-memory material. Nat Mater 2021; 20:242-249. [PMID: 32868876 DOI: 10.1038/s41563-020-0789-2] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 07/29/2020] [Indexed: 06/11/2023]
Abstract
Shape-memory polymeric materials lack long-range molecular order that enables more controlled and efficient actuation mechanisms. Here, we develop a hierarchical structured keratin-based system that has long-range molecular order and shape-memory properties in response to hydration. We explore the metastable reconfiguration of the keratin secondary structure, the transition from α-helix to β-sheet, as an actuation mechanism to design a high-strength shape-memory material that is biocompatible and processable through fibre spinning and three-dimensional (3D) printing. We extract keratin protofibrils from animal hair and subject them to shear stress to induce their self-organization into a nematic phase, which recapitulates the native hierarchical organization of the protein. This self-assembly process can be tuned to create materials with desired anisotropic structuring and responsiveness. Our combination of bottom-up assembly and top-down manufacturing allows for the scalable fabrication of strong and hierarchically structured shape-memory fibres and 3D-printed scaffolds with potential applications in bioengineering and smart textiles.
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Affiliation(s)
- Luca Cera
- Disease Biophysics Group, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Grant M Gonzalez
- Disease Biophysics Group, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Qihan Liu
- Disease Biophysics Group, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Suji Choi
- Disease Biophysics Group, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Christophe O Chantre
- Disease Biophysics Group, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Juncheol Lee
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
| | - Rudy Gabardi
- Disease Biophysics Group, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Myung Chul Choi
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
| | - Kwanwoo Shin
- Department of Chemistry and Institute of Biological Interfaces, Sogang University, Seoul, Korea
| | - Kevin Kit Parker
- Disease Biophysics Group, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA.
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Pope BD, Warren CR, Dahl MO, Pizza CV, Henze DE, Sinatra NR, Gonzalez GM, Chang H, Liu Q, Glieberman AL, Ferrier JP, Cowan CA, Parker KK. Fattening chips: hypertrophy, feeding, and fasting of human white adipocytes in vitro. Lab Chip 2020; 20:4152-4165. [PMID: 33034335 PMCID: PMC7818847 DOI: 10.1039/d0lc00508h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Adipose is a distributed organ that performs vital endocrine and energy homeostatic functions. Hypertrophy of white adipocytes is a primary mode of both adaptive and maladaptive weight gain in animals and predicts metabolic syndrome independent of obesity. Due to the failure of conventional culture to recapitulate adipocyte hypertrophy, technology for production of adult-size adipocytes would enable applications such as in vitro testing of weight loss therapeutics. To model adaptive adipocyte hypertrophy in vitro, we designed and built fat-on-a-chip using fiber networks inspired by extracellular matrix in adipose tissue. Fiber networks extended the lifespan of differentiated adipocytes, enabling growth to adult sizes. By micropatterning preadipocytes in a native cytoarchitecture and by adjusting cell-to-cell spacing, rates of hypertrophy were controlled independent of culture time or differentiation efficiency. In vitro hypertrophy followed a nonlinear, nonexponential growth model similar to human development and elicited transcriptomic changes that increased overall similarity with primary tissue. Cells on the chip responded to simulated meals and starvation, which potentiated some adipocyte endocrine and metabolic functions. To test the utility of the platform for therapeutic development, transcriptional network analysis was performed, and retinoic acid receptors were identified as candidate drug targets. Regulation by retinoid signaling was suggested further by pharmacological modulation, where activation accelerated and inhibition slowed hypertrophy. Altogether, this work presents technology for mature adipocyte engineering, addresses the regulation of cell growth, and informs broader applications for synthetic adipose in pharmaceutical development, regenerative medicine, and cellular agriculture.
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Affiliation(s)
- Benjamin D Pope
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Pierce Hall, Room 318, 29 Oxford Street, Cambridge, MA 02138, USA. and Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Curtis R Warren
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Madeleine O Dahl
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Pierce Hall, Room 318, 29 Oxford Street, Cambridge, MA 02138, USA.
| | - Christina V Pizza
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Pierce Hall, Room 318, 29 Oxford Street, Cambridge, MA 02138, USA.
| | - Douglas E Henze
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Pierce Hall, Room 318, 29 Oxford Street, Cambridge, MA 02138, USA.
| | - Nina R Sinatra
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Pierce Hall, Room 318, 29 Oxford Street, Cambridge, MA 02138, USA.
| | - Grant M Gonzalez
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Pierce Hall, Room 318, 29 Oxford Street, Cambridge, MA 02138, USA.
| | - Huibin Chang
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Pierce Hall, Room 318, 29 Oxford Street, Cambridge, MA 02138, USA.
| | - Qihan Liu
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Pierce Hall, Room 318, 29 Oxford Street, Cambridge, MA 02138, USA.
| | - Aaron L Glieberman
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Pierce Hall, Room 318, 29 Oxford Street, Cambridge, MA 02138, USA.
| | - John P Ferrier
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Pierce Hall, Room 318, 29 Oxford Street, Cambridge, MA 02138, USA.
| | - Chad A Cowan
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA and Harvard Stem Cell Institute, Cambridge, MA 02138, USA
| | - Kevin Kit Parker
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Pierce Hall, Room 318, 29 Oxford Street, Cambridge, MA 02138, USA. and Harvard Stem Cell Institute, Cambridge, MA 02138, USA
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Ahn S, Chantre CO, Ardoña HAM, Gonzalez GM, Campbell PH, Parker KK. Biomimetic and estrogenic fibers promote tissue repair in mice and human skin via estrogen receptor β. Biomaterials 2020; 255:120149. [PMID: 32521331 PMCID: PMC9812367 DOI: 10.1016/j.biomaterials.2020.120149] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 05/22/2020] [Accepted: 05/22/2020] [Indexed: 01/07/2023]
Abstract
The dynamic changes in estrogen levels throughout aging and during the menstrual cycle influence wound healing. Elevated estrogen levels during the pre-ovulation phase accelerate tissue repair, whereas reduced estrogen levels in post-menopausal women lead to slow healing. Although previous reports have shown that estrogen may potentiate healing by triggering the estrogen receptor (ER)-β signaling pathway, its binding to ER-α has been associated with severe collateral effects and has therefore limited its use as a therapeutic agent. To this end, soy phytoestrogens, which preferentially bind to the ER-β, are currently being explored as a safer therapeutic alternative to estrogen. However, the development and evaluation of phytoestrogen-based materials as local ER-β modulators remains largely unexplored. Here, we engineered biomimetic and estrogenic nanofiber wound dressings built from soy protein isolate (SPI) and hyaluronic acid (HA) using immersion rotary jet spinning. These engineered scaffolds were shown to successfully recapitulate the native dermal architecture, while delivering an ER-β-triggering phytoestrogen (genistein). When tested in ovariectomized mouse and ex vivo human skin tissues, HA/SPI scaffolds outperformed controls (no treatment or HA only scaffolds) towards promoting cutaneous tissue repair. These improved healing outcomes were prevented when the ER-β pathway was genetically or chemically inhibited. Our findings suggest that estrogenic fibrous scaffolds facilitate skin repair by ER-β activation.
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Affiliation(s)
| | | | | | | | | | - Kevin Kit Parker
- Corresponding author: Kevin Kit Parker, 29 Oxford St. (Rm. 321) Cambridge, MA, 02138, Tel: (617) 495-2850, Fax: (617) 495-9837,
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Chantre CO, Gonzalez GM, Ahn S, Cera L, Campbell PH, Hoerstrup SP, Parker KK. Porous Biomimetic Hyaluronic Acid and Extracellular Matrix Protein Nanofiber Scaffolds for Accelerated Cutaneous Tissue Repair. ACS Appl Mater Interfaces 2019; 11:45498-45510. [PMID: 31755704 DOI: 10.1021/acsami.9b17322] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Recent reports suggest the utility of extracellular matrix (ECM) molecules as raw components in scaffolding of engineered materials. However, rapid and tunable manufacturing of ECM molecules into fibrous structures remains poorly developed. Here we report on an immersion rotary jet-spinning (iRJS) method to show high-throughput manufacturing (up to ∼1 g/min) of hyaluronic acid (HA) and other ECM fiber scaffolds using different spinning conditions and postprocessing modifications. This system allowed control over a variety of scaffold material properties, which enabled the fabrication of highly porous (70-95%) and water-absorbent (swelling ratio ∼2000-6000%) HA scaffolds with soft-tissue mimetic mechanical properties (∼0.5-1.5 kPa). Tuning these scaffolds' properties enabled the identification of porosity (∼95%) as a key facilitator for rapid and in-depth cellular ingress in vitro. We then demonstrated that porous HA scaffolds accelerated granulation tissue formation, neovascularization, and reepithelialization in vivo, altogether potentiating faster wound closure and tissue repair. Collectively, this scalable and versatile manufacturing approach enabled the fabrication of tunable ECM-mimetic nanofiber scaffolds that may provide an ideal first building block for the design of all-in-one healing materials.
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Affiliation(s)
- Christophe O Chantre
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , Massachusetts 02138 , United States
- Institute for Regenerative Medicine , University of Zurich , Zurich 8044 ZH , Switzerland
| | - Grant M Gonzalez
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - Seungkuk Ahn
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - Luca Cera
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - Patrick H Campbell
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - Simon P Hoerstrup
- Institute for Regenerative Medicine , University of Zurich , Zurich 8044 ZH , Switzerland
| | - Kevin Kit Parker
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , Massachusetts 02138 , United States
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Abstract
Engineering bioscaffolds for improved cutaneous tissue regeneration remains a healthcare challenge because of the increasing number of patients suffering from acute and chronic wounds. To help address this problem, we propose to utilize alfalfa, an ancient medicinal plant that contains antibacterial/oxygenating chlorophylls and bioactive phytoestrogens, as a building block for regenerative wound dressings. Alfalfa carries genistein, which is a major phytoestrogen known to accelerate skin repair. The scaffolds presented herein were built from composite alfalfa and polycaprolactone (PCL) nanofibers with hydrophilic surface and mechanical stiffness that recapitulate the physiological microenvironments of skin. This composite scaffold was engineered to have aligned nanofibrous architecture to accelerate directional cell migration. As a result, alfalfa-based composite nanofibers were found to enhance the cellular proliferation of dermal fibroblasts and epidermal keratinocytes in vitro. Finally, these nanofibers exhibited reproducible regenerative functionality by promoting re-epithelialization and granulation tissue formation in both mouse and human skin, without requiring additional proteins, growth factors, or cells. Overall, these findings demonstrate the potential of alfalfa-based nanofibers as a regenerative platform toward accelerating cutaneous tissue repair.
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Affiliation(s)
- Seungkuk Ahn
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - Herdeline Ann M Ardoña
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - Patrick H Campbell
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - Grant M Gonzalez
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - Kevin Kit Parker
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , Massachusetts 02138 , United States
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Bialek R, Konrad F, Kern J, Aepinus C, Cecenas L, Gonzalez GM, Just-Nübling G, Willinger B, Presterl E, Lass-Flörl C, Rickerts V. PCR based identification and discrimination of agents of mucormycosis and aspergillosis in paraffin wax embedded tissue. J Clin Pathol 2006; 58:1180-4. [PMID: 16254108 PMCID: PMC1770765 DOI: 10.1136/jcp.2004.024703] [Citation(s) in RCA: 185] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Invasive fungal infections are often diagnosed by histopathology without identification of the causative fungi, which show significantly different antifungal susceptibilities. AIMS To establish and evaluate a system of two seminested polymerase chain reaction (PCR) assays to identify and discriminate between agents of aspergillosis and mucormycosis in paraffin wax embedded tissue samples. METHODS DNA of 52 blinded samples from five different centres was extracted and used as a template in two PCR assays targeting the mitochondrial aspergillosis DNA and the 18S ribosomal DNA of zygomycetes. RESULTS Specific fungal DNA was identified in 27 of 44 samples in accordance with a histopathological diagnosis of zygomycosis or aspergillosis, respectively. Aspergillus fumigatus DNA was amplified from one specimen of zygomycosis (diagnosed by histopathology). In four of 16 PCR negative samples no human DNA was amplified, possibly as a result of the destruction of DNA before paraffin wax embedding. In addition, eight samples from clinically suspected fungal infections (without histopathological proof) were examined. The two PCR assays detected a concomitant infection with Absidia corymbifera and A fumigatus in one, and infections with Rhizopus arrhizus and A fumigatus in another two cases. CONCLUSIONS The two seminested PCR assays described here can support a histopathological diagnosis of mucormycosis or aspergillosis, and can identify the infective agent, thereby optimising antifungal treatment.
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Affiliation(s)
- R Bialek
- Institute for Tropical Medicine, University Hospital Tübingen, Keplerstrasse 15, 72074 Tübingen, Germany.
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Gonzalez GM, Werling LL. Release of [3H]dopamine from guinea pig striatal slices is modulated by sigma1 receptor agonists. Naunyn Schmiedebergs Arch Pharmacol 1997; 356:455-61. [PMID: 9349631 DOI: 10.1007/pl00005076] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Sigma receptors are found in motor and limbic areas in the brains of humans, non-human primates, and rodents. The most extensive pharmacological studies of ligand binding to sigma receptors have utilized brain tissue from guinea pigs, where two subtypes of sigma receptor, designated sigma1 and sigma2, have been identified. Few functional roles for sigma receptors have been described. Their location in guinea pig striatum, a terminal field of dopaminergic projections arising from the substantia nigra, suggested that this tissue would be a logical choice in which to examine physiological properties of sigma receptor activation. We found that sigma1 receptor agonists inhibited N-methyl-D-aspartate-stimulated [3H]dopamine release from guinea pig striatal slices in a concentration-dependent manner. The inhibition by sigma1 receptor agonists was reversed by a selective sigma1 receptor antagonist, as well as by a non-subtype-selective sigma receptor antagonist. The ability of agonists working through sigma1 receptors, but not through sigma2 receptors, to inhibit the stimulated release of catecholamines appears to be a unique characteristic of guinea pig striatum. We have previously reported that in rat striatum and hippocampus, as well as in guinea pig nucleus accumbens, prefrontal cortex, and hippocampus, activation of either sigma receptor subtype inhibits such release. Stimulated release of [3H]dopamine from guinea pig striatum was also inhibited by the phencyclidine receptor agonist dizocilpine, but this inhibition was not reversed by the sigma receptor antagonists. Therefore, the inhibition produced by sigma receptor agonists was not mediated via the phencyclidine binding site within the N-methyl-D-aspartate-operated cation channel. Our findings support the hypothesis that sigma receptor activation provides a mechanism of modulating dopamine release from striatum, and that striatal tissue from guinea pigs appears to be an appropriate model for characterizing sigma1 receptor-mediated effects.
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Affiliation(s)
- G M Gonzalez
- Department of Pharmacology, The George Washington University Medical Center, Washington, DC 20037, USA
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Abstract
The development and validation of the College Drinking Attitude Scale (CDAS) are described. Based on a sample of over 4,000 college students, an item analysis, internal consistency analysis, and criterion validity analysis procedures were performed. The author concludes that the CDAS is a valid and reliable instrument that could be used to assess responsible attitudes toward the use of alcohol among college students.
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Affiliation(s)
- G M Gonzalez
- Department of Counselor Education, University of Florida, Gainesville 32611
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