TET2-Loss-of-Function-Driven Clonal Hematopoiesis Exacerbates Experimental Insulin Resistance in Aging and Obesity

Human aging is frequently accompanied by the acquisition of somatic mutations in the hematopoietic system that induce clonal hematopoiesis, leading to the development of a mutant clone of hematopoietic progenitors and leukocytes. This somatic-mutation-driven clonal hematopoiesis has been associated with an increased incidence of cardiovascular disease and type 2 diabetes, but whether this epidemiological association reflects a direct, causal contribution of mutant hematopoietic and immune cells to age-related metabolic abnormalities remains unexplored. Here, we show that inactivating mutations in the epigenetic regulator TET2, which lead to clonal hematopoiesis, aggravate age- and obesity-related insulin resistance in mice. This metabolic dysfunction is paralleled by increased expression of the pro-inflammatory cytokine IL-1β in white adipose tissue, and it is suppressed by pharmacological inhibition of NLRP3 inflammasome-mediated IL-1β production. These findings support a causal contribution of somatic TET2 mutations to insulin resistance and type 2 diabetes. [Display omitted] •TET2-deficiency-driven clonal hematopoiesis aggravates insulin resistance in aged mice•TET2-deficiency-driven clonal hematopoiesis aggravates insulin resistance in obese mice•TET2-deficiency-driven clonal hematopoiesis increases IL-1β levels in adipose tissue•NLRP3 inhibition prevents the effects of TET2-deficient cells on insulin sensitivity Somatic-mutation-driven clonal hematopoiesis is emerging as a potent risk factor for a variety of age-related conditions. Fuster et al. show that clonal hematopoiesis driven by TET2 mutations aggravates insulin resistance in mice. These findings support a causal contribution of somatic TET2 mutations to metabolic syndrome and type 2 diabetes.