Affiliation: | 1. Department of Nutrition and Integrative Physiology, The University of Utah, Salt Lake City, Utah, USA;2. Geriatric Research Education and Clinical Center, Veteran's Affairs Medical Center-Salt Lake City, Salt Lake City, Utah, USA Division of Cardiology, Department of Internal Medicine, The University of Utah School of Medicine, Salt Lake City, Utah, USA;3. Geriatric Research Education and Clinical Center, Veteran's Affairs Medical Center-Salt Lake City, Salt Lake City, Utah, USA;4. Department of Kinesiology, The University of Texas at Arlington, Arlington, Texas, USA;5. Department of Nutrition and Integrative Physiology, The University of Utah, Salt Lake City, Utah, USA Geriatric Research Education and Clinical Center, Veteran's Affairs Medical Center-Salt Lake City, Salt Lake City, Utah, USA Division of Geriatrics, Department of Internal Medicine, The University of Utah School of Medicine, Salt Lake City, Utah, USA Department of Biochemistry, The University of Utah, Salt Lake City, Utah, USA Nora Eccles Harrison Cardiovascular Research and Training Institute, The University of Utah, Salt Lake City, Utah, USA |
Abstract: | Aging results in an elevated burden of senescent cells, senescence-associated secretory phenotype (SASP), and tissue infiltration of immune cells contributing to chronic low-grade inflammation and a host of age-related diseases. Recent evidence suggests that the clearance of senescent cells alleviates chronic inflammation and its associated dysfunction and diseases. However, the effect of this intervention on metabolic function in old age remains poorly understood. Here, we demonstrate that dasatinib and quercetin (D&Q) have senolytic effects, reducing age-related increase in senescence-associated β-galactosidase, expression of p16 and p21 gene and P16 protein in perigonadal white adipose tissue (pgWAT; all p ≤ 0.04). This treatment also suppressed age-related increase in the expression of a subset of pro-inflammatory SASP genes (mcp1, tnf-α, il-1α, il-1β, il-6, cxcl2, and cxcl10), crown-like structures, abundance of T cells and macrophages in pgWAT (all p ≤ 0.04). In the liver and skeletal muscle, we did not find a robust effect of D&Q on senescence and inflammatory SASP markers. Although we did not observe an age-related difference in glucose tolerance, D&Q treatment improved fasting blood glucose (p = 0.001) and glucose tolerance (p = 0.007) in old mice that was concomitant with lower hepatic gluconeogenesis. Additionally, D&Q improved insulin-stimulated suppression of plasma NEFAs (p = 0.01), reduced fed and fasted plasma triglycerides (both p ≤ 0.04), and improved systemic lipid tolerance (p = 0.006). Collectively, results from this study suggest that D&Q attenuates adipose tissue inflammation and improves systemic metabolic function in old age. These findings have implications for the development of therapeutic agents to combat metabolic dysfunction and diseases in old age. |