BIOMEDICAL ENGINEERING

The emergence of dedicated, small animal imaging systems provides an ideal opportunity to study obesity and metabolism in living organisms.
These in vivo imaging capabilities enable the non-invasive assessment of a variety of physiologic parameters that will help to determine the effects of genetic, environmental, and therapeutic factors on lipid accumulation and metabolism. MR imaging is well suited for quantifying fat depots (e.g., visceral, subcutaneous, hepatic, muscular). We are evaluating the effects of diet and genetics on lipid accumulation and metabolism in the liver, muscle, and adipose tissue compartments.

We developed ratio MRI [lipid/(lipid+water)] methods for assessing lipid depots and compare measurement variability to biological differences in lean controls (spontaneously hypertensive rats, SHRs), dietary obese (SHR-DO), and genetic/dietary obese (SHROBs) animals.
SHROB had significantly more subcutaneous adipose tissue, indicating a strong genetic component to this fat depot. Liver ratios in SHR-DO and SHROB were higher than SHR, indicating elevated fat content. Among SHROBs, evidence suggested a phenotype having elevated liver ratios and visceral adipose tissue volumes.

Host: Professor David Wilson