ABSTRACT
Another phenotype developed by these mice, similar to the situation with humans carrying a natural mutation in the CYP19 gene, is a lipid and carbohydrate phenotype. ArKO mice, both male and female, develop a progressive increase in abdominal adiposity, involving both the gonadal and infra-renal fat deposits. This is associated with increased plasma triglycerides and cholesterol, insulin resistance and hyperleptinemia. Hepatic steatosis is also present. Interestingly, the increased adiposity is not accompanied by a marked increase in body weight. This is because there is a corresponding decrease in lean body mass, most likely skeletal muscle, which is associated with a decrease in activity. This adiposity phenotype is reversed dramatically within three weeks upon administration of estradiol in the form of implants. A similar phenotype has been reported for the ERαKO mice, so these two models are in accordance as far as this phenotype is concerned.
