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Fujiki R, Lee JY, Jurgens JA, Whitman MC, Engle EC. Isolation and Culture of Oculomotor, Trochlear, and Spinal Motor Neurons from Prenatal Islmn:GFP Transgenic Mice. J Vis Exp 2019:10.3791/60440. [PMID: 31789317 PMCID: PMC7036286 DOI: 10.3791/60440] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Oculomotor neurons (CN3s) and trochlear neurons (CN4s) exhibit remarkable resistance to degenerative motor neuron diseases such as amyotrophic lateral sclerosis (ALS) when compared to spinal motor neurons (SMNs). The ability to isolate and culture primary mouse CN3s, CN4s, and SMNs would provide an approach to study mechanisms underlying this selective vulnerability. To date, most protocols use heterogeneous cell cultures, which can confound the interpretation of experimental outcomes. To minimize the problems associated with mixed-cell populations, pure cultures are indispensable. Here, the first protocol describes in detail how to efficiently purify and cultivate CN3s/CN4s alongside SMNs counterparts from the same embryos using embryonic day 11.5 (E11.5) IslMN:GFP transgenic mouse embryos. The protocol provides details on the tissue dissection and dissociation, FACS-based cell isolation, and in vitro cultivation of cells from CN3/CN4 and SMN nuclei. This protocol adds a novel in vitro CN3/CN4 culture system to existing protocols and simultaneously provides a pure species- and age-matched SMN culture for comparison. Analyses focusing on the morphological, cellular, molecular, and electrophysiological characteristics of motor neurons are feasible in this culture system. This protocol will enable research into the mechanisms that define motor neuron development, selective vulnerability, and disease.
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Affiliation(s)
- Ryosuke Fujiki
- Department of Neurology, Boston Children's Hospital; FM Kirby Neurobiology Center, Boston Children's Hospital; Department of Neurology, Harvard Medical School; Medical Genetics Training Program, Harvard Medical School; Department of Neurology, Kokura Memorial Hospital
| | - Joun Y Lee
- Department of Neurology, Boston Children's Hospital; FM Kirby Neurobiology Center, Boston Children's Hospital; Department of Genetics, Albert Einstein College of Medicine
| | - Julie A Jurgens
- Department of Neurology, Boston Children's Hospital; FM Kirby Neurobiology Center, Boston Children's Hospital; Department of Neurology, Harvard Medical School; Broad Institute of M.I.T. and Harvard
| | - Mary C Whitman
- FM Kirby Neurobiology Center, Boston Children's Hospital; Department of Ophthalmology, Boston Children's Hospital; Department of Ophthalmology, Harvard Medical School
| | - Elizabeth C Engle
- Department of Neurology, Boston Children's Hospital; FM Kirby Neurobiology Center, Boston Children's Hospital; Department of Neurology, Harvard Medical School; Medical Genetics Training Program, Harvard Medical School; Department of Ophthalmology, Boston Children's Hospital; Department of Ophthalmology, Harvard Medical School; Broad Institute of M.I.T. and Harvard; Howard Hughes Medical Institute;
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Whitman MC, Bell JL, Nguyen EH, Engle EC. Ex Vivo Oculomotor Slice Culture from Embryonic GFP-Expressing Mice for Time-Lapse Imaging of Oculomotor Nerve Outgrowth. J Vis Exp 2019. [PMID: 31380850 DOI: 10.3791/59911] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Accurate eye movements are crucial for vision, but the development of the ocular motor system, especially the molecular pathways controlling axon guidance, has not been fully elucidated. This is partly due to technical limitations of traditional axon guidance assays. To identify additional axon guidance cues influencing the oculomotor nerve, an ex vivo slice assay to image the oculomotor nerve in real-time as it grows towards the eye was developed. E10.5 IslMN-GFP embryos are used to generate ex vivo slices by embedding them in agarose, slicing on a vibratome, then growing them in a microscope stage-top incubator with time-lapse photomicroscopy for 24-72 h. Control slices recapitulate the in vivo timing of outgrowth of axons from the nucleus to the orbit. Small molecule inhibitors or recombinant proteins can be added to the culture media to assess the role of different axon guidance pathways. This method has the advantages of maintaining more of the local microenvironment through which axons traverse, not axotomizing the growing axons, and assessing the axons at multiple points along their trajectory. It can also identify effects on specific subsets of axons. For example, inhibition of CXCR4 causes axons still within the midbrain to grow dorsally rather than ventrally, but axons that have already exited ventrally are not affected.
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Affiliation(s)
- Mary C Whitman
- Department of Ophthalmology, Boston Children's Hospital; Department of Ophthalmology, Harvard Medical School; F.M. Kirby Neurobiology Center, Boston Children's Hospital;
| | - Jessica L Bell
- Department of Ophthalmology, Boston Children's Hospital; F.M. Kirby Neurobiology Center, Boston Children's Hospital
| | - Elaine H Nguyen
- Department of Ophthalmology, Boston Children's Hospital; F.M. Kirby Neurobiology Center, Boston Children's Hospital
| | - Elizabeth C Engle
- Department of Ophthalmology, Boston Children's Hospital; Department of Ophthalmology, Harvard Medical School; F.M. Kirby Neurobiology Center, Boston Children's Hospital; Department of Neurology, Boston Children's Hospital; Department of Neurology, Harvard Medical School; Howard Hughes Medical Institute
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Peng M, He Q, Li S, Li L, Ma H. Integrated analysis of proteomics-delineated and metabolomics-delineated hepatic metabolic responses to (-)-hydroxycitric acid in chick embryos. J Cell Biochem 2019; 120:1258-1270. [PMID: 30317645 DOI: 10.1002/jcb.27085] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 04/26/2018] [Indexed: 01/24/2023]
Abstract
(-)-Hydroxycitric acid [(-)-HCA] is widely used as a nutritional supplement to control body weight and fat accumulation in animals and humans, whereas the underlying biochemical mechanism is unclear. Broiler chicken was used as a model for studies of obesity due to its natural hyperglycemia and being insulin resistant. The current study aimed to obtain a systematic view of serum metabolites and hepatic proteins and well understand the mechanism of hepatic metabolic response to (-)-HCA treatment in chick embryos. The results showed that 22, 90, and 82 of differentially expressed proteins were identified at E14d, E19d, and H1d in chick embryos treated with (-)-HCA, respectively. Meanwhile, 5, 83, and 88 of serum metabolites significantly changed at E14d, E19d, and H1d in chick embryos after (-)-HCA treatment. Bioinformatics analysis showed that the key proteins and metabolites, which were significantly altered in chick embryos treated with (-)-HCA, were mainly involved in the citrate cycle, glycolysis/gluconeogenesis, fatty acid metabolism, and pyruvate metabolism. Our data indicated that (-)-HCA treatment might promote fat metabolism via regulating the key protein expression levels and metabolite contents in the citrate cycle, glycolysis/gluconeogenesis, and oxidative phosphorylation during chicken embryonic development. These results will deepen our understanding of the mechanism of fat reduction by (-)-HCA and provide substantial information for (-)-HCA as a nutritional supplement to control body weight gain and curb obesity-related diseases.
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Affiliation(s)
- Mengling Peng
- Key Laboratory of Animal Physiology and Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.,Key Laboratory of Animal Physiology and Biochemistry, Ministry of Agriculture, Nanjing, China
| | - Qianqian He
- Key Laboratory of Animal Physiology and Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.,Key Laboratory of Animal Physiology and Biochemistry, Ministry of Agriculture, Nanjing, China
| | - Shengnan Li
- Key Laboratory of Animal Physiology and Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.,Key Laboratory of Animal Physiology and Biochemistry, Ministry of Agriculture, Nanjing, China
| | - Longlong Li
- Key Laboratory of Animal Physiology and Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.,Key Laboratory of Animal Physiology and Biochemistry, Ministry of Agriculture, Nanjing, China
| | - Haitian Ma
- Key Laboratory of Animal Physiology and Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.,Key Laboratory of Animal Physiology and Biochemistry, Ministry of Agriculture, Nanjing, China
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