Adiposity-Independent Effects of Aging on Insulin Sensitivity and Clearance in Mice and Humans
Program in Molecular Medicine; Department of Medicine, Division of Endocrinology, Metabolism, and Diabetes
Cellular and Molecular Physiology | Endocrinology | Hormones, Hormone Substitutes, and Hormone Antagonists | Lipids | Nutritional and Metabolic Diseases
OBJECTIVE: Aging is associated with impaired insulin sensitivity and increased prevalence of type 2 diabetes. However, it remains unclear whether aging-associated insulin resistance is due to increased adiposity or other age-related factors. To address this question, the impact of aging on insulin sensitivity was investigated independently of changes in body composition.
METHODS: Cohorts of mice aged 4 to 8 months ("young") and 18 to 27 months ("aged") exhibiting similar body composition were characterized for glucose metabolism on chow and high-fat diets. Insulin sensitivity was assessed by hyperinsulinemic-euglycemic clamp analyses. The relationship between aging and insulin resistance in humans was investigated in 1,250 nondiabetic Mexican Americans who underwent hyperinsulinemic-euglycemic clamps.
RESULTS: In mice with similar body composition, age had no detrimental effect on plasma glucose and insulin levels. While aging did not diminish glucose tolerance, hyperinsulinemic-euglycemic clamps demonstrated impaired insulin sensitivity and reduced insulin clearance in aged mice on chow and high-fat diets. Consistent with results in the mouse, age remained an independent determinant of insulin resistance after adjustment for body composition in Mexican American males.
CONCLUSIONS: This study demonstrates that in addition to altered body composition, adiposity-independent mechanisms also contribute to aging-associated insulin resistance in mice and humans.
DOI of Published Version
Obesity (Silver Spring). 2019 Mar;27(3):434-443. doi: 10.1002/oby.22418. Link to article on publisher's site
Obesity (Silver Spring, Md.)
Ehrhardt N, Cui J, Dagdeviren S, Saengnipanthkul S, Goodridge HS, Kim JK, Lantier L, Guo X, Chen YI, Raffel LJ, Buchanan TA, Hsueh WA, Rotter JI, Goodarzi MO, Peterfy M. (2019). Adiposity-Independent Effects of Aging on Insulin Sensitivity and Clearance in Mice and Humans. Program in Molecular Medicine Publications and Presentations. https://doi.org/10.1002/oby.22418. Retrieved from https://escholarship.umassmed.edu/pmm_pp/118