Periuterine Adipose Tissue Remodeling in Rats Offered a Choice of Lard, Sucrose, and Chow

The impact of obesity on adipose tissue expansion differs with each adipose depot throughout the body, suggesting that obesity affects adipose tissue in a regional manner. We determined if free access to lard, sucrose solution, and chow (choice diet) would result in expansion (i.e. hypertrophy and hyperplasia) of periuterine adipose tissue and development of metabolic syndrome. Sprague-Dawley female rats were divided into 2 weight-matched groups: 1) choice group: free access to chow, sucrose solution, and lard and 2) chow group: rodent chow for 3 weeks. Choice rats had greater visceral adiposity, serum concentrations of triglycerides (30.95 ± 2.48 v. 45.20 ± 3.81 mg/dL) and fasting glucose (121.5 ± 3.9 v. 110 ± 2.4 mg/dL), and higher blood pressure (95.79 ± 1.82 v. 88.55 ± 1.25 mm Hg) compared to chow rats. Adipocyte morphology was assessed in hematoxylin and eosin-stained periuterine adipose tissue sections using NIS Elements software. Cross-sectional area/cell was greater in periuterine adipose tissue from choice compared to chow rats, indicating a hypertrophic response (779.6 ± 47.64 vs. 492.0 ± 27.76 μm2/cell, p=0.0001). Number of cells/unit area was smaller in periuterine adipose tissue from choice rats, indicating a hypoplastic response (13.9 x 10-5 ± 0.880 x 10-5 vs. 20.4 x 10-5 ±0.910 x 10-5 cells/μm2, p=0.0001). In conclusion, choice diet induced features of metabolic syndrome and periuterine adipose tissue expansion via hypertrophy in female rats.