Authors
Min, So YunFaculty Advisor
Silvia CorveraAcademic Program
Interdisciplinary Graduate ProgramUMass Chan Affiliations
Program in Molecular MedicineDocument Type
Doctoral DissertationPublication Date
2016-12-16Keywords
Human adipocyteWhite adipocyte
Brown adipocyte
Brite adipocyte
Beige adipocyte
Metabolism
Thermogenic adipose tissue
Insulin resistance
Glucose homeostasis
Adipocyte implantation
Biology
Cell Biology
Medical Cell Biology
Nutritional and Metabolic Diseases
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Show full item recordAbstract
During embryonic development, adipocytes emerge from microvasculature. Lineage-‐tracing studies in mice have shown that adipocyte progenitors reside in the adipose tissue capillaries. However, the direct evidence of an association between adipocyte progenitors and vasculature in humans is lacking. A specific class of adipocytes (brown and beige/brite) expresses the uncoupling protein 1 (UCP1), which consumes glucose and fatty acids to generate heat. The abundance of UCP1- containing adipocytes correlates with a lean metabolically healthy phenotype in human. However, a causal relationship between the presence of these cells and metabolic benefits in human is not clear. In this thesis, I report human adipocyte progenitors proliferate in response to pro-angiogenic factors in association with adipose capillary networks in-vitro. The capillary-derived adipocytes transform from being UCP1-negative to positive upon adenylate cyclase activation, a defining feature of the brite/beige phenotype. Activated cells have denser, round mitochondria with UCP1 protein, and display uncoupled respiration. When implanted into NOD-scid IL2rgnull (NSG) mice, the adipocytes can form a vascularized fat pad that induces vascularization and becomes integrated into mouse circulatory system. In normal or high fat diet-fed NSG mice, activated brite/beige adipocytes enhance systemic glucose tolerance and improved hepatic steatosis, thus providing evidence for their potential therapeutic use. The adipocytes also express neuroendocrine and secretory factors such as Interleukin-33, proprotein convertase PCSK1 and proenkephalin PENK, which are correlated with human obesity. Finally, analyses on single-cell clones of capillary-sprout cells reveal the existence of diverse adipogenic progenitor populations. Further characterization of the clones will define the identifying features of the diverse adipocyte progenitor types that exist in human adipose tissue.DOI
10.13028/M20598Permanent Link to this Item
http://hdl.handle.net/20.500.14038/32254Rights
Licensed under a Creative Commons licenseDistribution License
http://creativecommons.org/licenses/by/4.0/ae974a485f413a2113503eed53cd6c53
10.13028/M20598
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