Hepatic fat during fasting and refeeding by MRI fat quantification.

Area of Science:

• Biomedical Imaging
• Magnetic Resonance Imaging
• Hepatic Metabolism

Background:

• Hepatic fat content is a key indicator of metabolic health.
• Accurate, non-invasive methods are needed to monitor dynamic changes in liver fat.

Purpose of the Study:

• To assess the sensitivity of high-field small animal MRI to dynamic changes in liver fat.
• To investigate the influence of prandial state on hepatic fat imaging.

Main Methods:

• Asymmetric spin-echo MRI sequences were used to acquire data at three timepoints over 48 hours.
• Mice were subjected to a fasting/refeeding protocol to induce dynamic changes in hepatic fat.
• Fat fraction maps were generated, and regions of interest in the liver were analyzed over time.

Main Results:

• Five of six fasted mice showed a significant increase in hepatic fat fraction (average 0.54 ± 0.48).
• Refeeding led to a decrease in hepatic fat fraction.
• Statistical analysis confirmed significant effects of both fasting/refeeding and time on liver fat content (P = 0.003).

Conclusions:

• Fat-water MRI techniques are sensitive to short-term dietary-induced alterations in hepatic fat.
• MRI can reliably quantify dynamic changes in liver fat content in small animal models.