Quantitative determination of liver triglyceride levels with 3T ¹H-MR spectroscopy in mice with moderately elevated liver fat content.

Rationale And Objectives: To diagnose hepatic steatosis with noninvasive magnetic resonance (MR)-based measurements, threshold values of liver fat percentages are used. However, these differ between studies. Consequently, the choice of threshold values influences diagnostic accuracy, especially in subjects with borderline hepatic steatosis.

Measuring liver triglyceride content in mice: non-invasive magnetic resonance methods as an alternative to histopathology.

Object: Quantitative assessment of liver fat is highly relevant to preclinical liver research and should ideally be performed non-invasively. This study aimed to compare three non-invasive Magnetic Resonance (MR) and two histopathological methods against the reference standard of biochemically determined liver triglyceride content (LTC).

Materials And Methods: A total of 50 mice [21 C57Bl/6OlaHsd mice (C57Bl/6), nine low-density lipoprotein (LDL) receptor knock-out -/- (LDL -/-) mice and 20 C57BL/6 mice] received either a high-fat, high-fat-high-cholesterol or control diet, respectively.

Hepatic adaptation compensates inactivation of intestinal arginine biosynthesis in suckling mice.

Suckling mammals, including mice, differ from adults in the abundant expression of enzymes that synthesize arginine from citrulline in their enterocytes. To investigate the importance of the small-intestinal arginine synthesis for whole-body arginine production in suckling mice, we floxed exon 13 of the argininosuccinate synthetase (Ass) gene, which codes for a key enzyme in arginine biosynthesis, and specifically and completely ablated Ass in enterocytes by crossing Ass (fl) and Villin-Cre mice. Unexpectedly, Ass (fl/fl) /VilCre (tg/-) mice showed no developmental impairments.