Date on Senior Honors Thesis
5-2019
Document Type
Senior Honors Thesis
Degree Name
B.A.
Department
Biology
Author's Keywords
blood glucose; diabetes
Abstract
Adiponectin is a protein secreted from adipose (fat) tissue. It is secreted into the blood as either a trimer (low molecular weight), hexamer (middle molecular weight) or an 18-mer (high molecular weight). Adiponectin, particularly the high molecular weight (HMW) isoform, has been shown to increase insulin sensitivity, which is important for maintaining healthy blood glucose levels. Adiponectin levels have been shown to be decreased in individuals who are obese, and this may play a role in the diabetes which often accompanies obesity. PPARγ is a protein that is highly expressed in white adipose tissue and is responsible for regulating portions of metabolism such as glucose and fatty acid uptake and oxidation as well as proposed to be important in regulating adiponectin levels and the production of its high molecular weight isoform. This study examines the level of PPARγ and adiponectin isoforms in adipose tissue in a mouse model of obesity.
White adipose tissue samples were removed from mice fed a high-fat or low-fat diet for 6, 10, or 16 weeks. An enzyme-linked immunoassay (ELISA) was utilized for total adiponectin, HMW adiponectin, and PPARγ following homogenization and preparation of tissue sample. Levels of PPARγ, total adiponectin, and HMW adiponectin were statistically evaluated over the time course of the experiment both within and between the treatment groups.
The level of PPARγ was not different over the course of low-fat feeding; however, the levels of PPARγ were significantly (P
Results of this study suggest that, while there were some changes in PPARγ with high-fat feeding they were not correlated with alterations in the adipose tissue levels of adiponectin. This indicates that there is not a tight connection between PPARγ and regulation of adiponectin levels in this model of obesity
Recommended Citation
McDowell, Katelyn M., "PPARγ and high molecular weight adiponectin in white adipose tissue in an obesity model." (2019). College of Arts & Sciences Senior Honors Theses. Paper 187.
Retrieved from https://ir.library.louisville.edu/honors/187
Lay Summary
Obese individuals tend to have a more difficult time regulating blood glucose levels for a variety of reasons. This experiment utilizes normal weight and obese mice on controlled diets for different time periods. The protein adiponectin, which assists in the regulation of blood glucose levels, was measured in the cytoplasmic fraction of cells from white fat in normal weight and obese mice of all time points. Additionally, PPARγ a protein that assists in the production of the adiponectin, was measured in the nucleus of the cells of white fat in mice under the same controls. A better understanding of the mechanisms by which blood glucose regulation occurs could assist in creating drugs that will yield more success in clinical applications of blood glucose control.
