Discipline: Biological Sciences
Subcategory: Cell and Molecular Biology
Shekinah Hernandez - Hampton University
Co-Author(s): Shamina Aubuchon, Hampton University, Hampton, VA
Obesity is defined as a complex disorder resulting from an excessive amount of body fat. Obese individuals are predisposed to diseases such as heart disease, cancer, depression, sleep apnea, high blood pressure, stroke and Type 2-diabetes (T2D). Bariatric weight loss surgery is a treatment option for people who are severely obese. The health benefits of bariatric surgery as it relates to metabolic diseases is impressive however, these benefits are not equally experienced across ethnicities. Studies by Coleman KJ et al. revealed that metabolic syndrome was less likely to resolve if bariatric surgery patients had a higher BMI at surgery, were older, were male or African American (AA). The aim of this project is to understand the differences in gene expression of proinflammatory molecules within adipose tissue of AA versus Caucasians (CC). We hypothesize that the expression of proinflammatory cytokines and orexigenic genes in adipose tissue will be increased in the male AA population when compared to equally obese male CC, which may cause decreased overall health benefits post bariatric surgery. To test this hypothesis, a SA Biosciences/Qiagen obesity RT² Profiler PCR Array was used to identify differences in the gene expression of obesity related genes in visceral and subcutaneous fat of AA and CC men. The results show that the peptide YY (PYY) gene is secreted by endocrine cells in the gut and mediates the regulation of pancreatic secretion, gut mobility and energy homeostasis. This gene has been found to be downregulated 19.98 fold in AA compared to CC. The neurotensin (NTS) gene is involved in the maintenance of gut structure and function, and in the regulation of fat metabolism. This gene was found to be downregulated 10.18 fold in AA compared to their equally obese CC counterparts. The Neuromedin B (NMB) gene was found to be upregulated in AA when compared to CC by 2.68 fold. Polymorphisms of NMB are associated with hunger, weight gain and obesity. Melanin concentrating hormone receptor 1 (MCHR1) is a gene involved in the neuronal regulation of food consumption and energy metabolism. In comparison to the CC men, this gene was found to be upregulated by 3.98 fold in AA. The glucagon (GCG) gene is secreted from gut endocrine cells and promotes nutrient absorption through distinct mechanisms. It was found to be downregulated by 3.59 fold in AA when compared to CC. The (ADIPOQ) gene is involved in the control of fat metabolism and insulin sensitivity. This gene was found to be upregulated in AA when compared to CC by 9.21 fold. These results clearly show that genes which positively regulate metabolism, seem to be downregulated in AA men compared to CC men and vice versa. In the future, we plan to explore the pathways related to key genes and molecules that were significantly expressed in the arrays. The long term goal of this project is to identify potential therapeutic targets that can be used to treat obesity.
Funder Acknowledgement(s): Minority Men’s Health Initiative (MMHI) grant
Faculty Advisor: Shamina Aubuchon, Shamina.aubuchon@hamptonu.edu
Role: In this project, I performed the PCR and data analysis. I also researched most of the background information, and analyzed the various genes and their ties to obesity.