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Kanuri B, Fong V, Ponny SR, Tallman KA, Rao SR, Porter N, Fliesler SJ, Patel SB. Generation and validation of a conditional knockout mouse model for the study of the Smith-Lemli-Opitz syndrome. J Lipid Res 2020; 62:100002. [PMID: 33410752 PMCID: PMC7890206 DOI: 10.1194/jlr.ra120001101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/08/2020] [Accepted: 11/17/2020] [Indexed: 11/20/2022] Open
Abstract
Smith-Lemli-Opitz Syndrome (SLOS) is a developmental disorder (OMIM #270400) caused by autosomal recessive mutations in the Dhcr7 gene, which encodes the enzyme 3β-hydroxysterol-Δ7 reductase. SLOS patients present clinically with dysmorphology and neurological, behavioral, and cognitive defects, with characteristically elevated levels of 7-dehydrocholesterol (7-DHC) in all bodily tissues and fluids. Previous mouse models of SLOS have been hampered by postnatal lethality when Dhcr7 is knocked out globally, while a hypomorphic mouse model showed improvement in the biochemical phenotype with aging and did not manifest most other characteristic features of SLOS. We report the generation of a conditional knockout of Dhcr7 (Dhcr7flx/flx), validated by generating a mouse with a liver-specific deletion (Dhcr7L-KO). Phenotypic characterization of liver-specific knockout mice revealed no significant changes in viability, fertility, growth curves, liver architecture, hepatic triglyceride secretion, or parameters of systemic glucose homeostasis. Furthermore, qPCR and RNA-Seq analyses of livers revealed no perturbations in pathways responsible for cholesterol synthesis, either in male or in female Dhcr7L-KO mice, suggesting that hepatic disruption of postsqualene cholesterol synthesis leads to minimal impact on sterol metabolism in the liver. This validated conditional Dhcr7 knockout model may now allow us to systematically explore the pathophysiology of SLOS, by allowing for temporal, cell and tissue-specific loss of DHCR7.
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Affiliation(s)
- Babunageswararao Kanuri
- Division of Endocrinology, Diabetes and Metabolism, University of Cincinnati, Cincinnati, OH, USA
| | - Vincent Fong
- Division of Endocrinology, Diabetes and Metabolism, University of Cincinnati, Cincinnati, OH, USA
| | - Sithara Raju Ponny
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Keri A Tallman
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, USA
| | - Sriganesh Ramachandra Rao
- Departments of Ophthalmology and Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo-State University of New York, Buffalo, NY, USA
| | - Ned Porter
- Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, USA
| | - Steven J Fliesler
- Departments of Ophthalmology and Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo-State University of New York, Buffalo, NY, USA; Graduate Program in Neuroscience, University at Buffalo- State University of New York, Buffalo, NY, USA; Research Service, VA Western New York Healthcare System, Buffalo, NY, USA
| | - Shailendra B Patel
- Division of Endocrinology, Diabetes and Metabolism, University of Cincinnati, Cincinnati, OH, USA.
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Sistiaga A, Wrangham R, Rothman JM, Summons RE. New Insights into the Evolution of the Human Diet from Faecal Biomarker Analysis in Wild Chimpanzee and Gorilla Faeces. PLoS One 2015; 10:e0128931. [PMID: 26061730 PMCID: PMC4465628 DOI: 10.1371/journal.pone.0128931] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Accepted: 05/01/2015] [Indexed: 01/19/2023] Open
Abstract
Our understanding of early human diets is based on reconstructed biomechanics of hominin jaws, bone and teeth isotopic data, tooth wear patterns, lithic, taphonomic and zooarchaeological data, which do not provide information about the relative amounts of different types of foods that contributed most to early human diets. Faecal biomarkers are proving to be a valuable tool in identifying relative proportions of plant and animal tissues in Palaeolithic diets. A limiting factor in the application of the faecal biomarker approach is the striking absence of data related to the occurrence of faecal biomarkers in non-human primate faeces. In this study we explored the nature and proportions of sterols and stanols excreted by our closest living relatives. This investigation reports the first faecal biomarker data for wild chimpanzee (Pan troglodytes) and mountain gorilla (Gorilla beringei). Our results suggest that the chemometric analysis of faecal biomarkers is a useful tool for distinguishing between NHP and human faecal matter, and hence, it could provide information for palaeodietary research and early human diets.
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Affiliation(s)
- Ainara Sistiaga
- Massachusetts Institute of Technology, Cambridge, United States of America
- Universidad de La Laguna, La Laguna, Spain
| | | | | | - Roger E. Summons
- Massachusetts Institute of Technology, Cambridge, United States of America
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Affiliation(s)
- Thomas Dayspring
- University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, NJ, and North Jersey Institute of Menopausal Lipidology, Wayne, NJ, USA.
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