Evaluation of Hepatic Steatosis in Rodents by Time-Domain Nuclear Magnetic Resonance

Abstract

Devices that analyze body composition of rodents by time-domain nuclear magnetic resonance (TD-NMR) are becoming popular in research centers that study metabolism. Theoretically, TD-NMR devices can also evaluate lipid content in isolated tissues. However, the accuracy of TD-NMR to determine hepatic steatosis in the liver of small laboratory animals has not been evaluated in detail. We observed that TD-NMR was able to detect increased lipid content in the liver of rats consuming high-fat diet (HFD) for 12 weeks and in genetically obese (Lepob/ob and Leprdb/db) mice. The lipid content determined by TD-NMR showed a positive correlation with triglyceride content measured by colorimetric assays. In contrast, TD-NMR did not detect hepatic steatosis in C57BL/6 mice consuming HFD for 4 or 12 weeks, despite their obesity and increased liver triglyceride content. These findings indicate that tissue mass and the severity of hepatic steatosis affect the sensitivity of TD-NMR to detect liver lipid content.

Spatiotemporal regulation of GIPR signaling impacts glucose homeostasis as revealed in studies of a common GIPR variant

“…Magnetic resonance imaging of body fat revealed that HFD-fed GIPR-Q350 mice have a lower fat mass and no change in lean mass as compared to GIPR-WT mice ( Figure 6B). Of note, the fat mass of HFD-fed GIPR-Q350 males, 16.6% of body weight, was comparable to values reported in the literature for fat mass of similarly aged WT mice fed a normal chow diet, ~16% of body mass (Pedroso et al, 2019;Sharma et al, 2019), demonstrating the near complete blunting of weight gain in GIPR-Q350 male mice on HFD.…”