El, K. | bioRxiv Science

bioRxiv2026

Legacy Effects of Early β-Adrenergic Stimulation Program Adipose Plasticity and Confer Metabolic Resilience in Obesity

Pathologic white adipose tissue (WAT) remodeling, characterized by fibrosis, inflammation, and adipocyte dysfunction, is a hallmark and driver of metabolic disease in obesity1. Here, we show that legacy effects of early physiological or pharmacological interventions driving adaptive adipose remodeling can mitigate maladaptive WAT remodeling and metabolic dysfunction when developing obesity later in life. Cold exposure or {beta}3-adrenergic receptor ({beta}3AR) agonism (CL316,243) induced thermogenic remodeling of WAT in male mice. After a prolonged recovery at room temperature, trained epididymal WAT reverted to an energy-storing state but retained a population of adipocytes resembling "metabolically flexible" visceral adipocytes found in human metabolically healthy obesity. The legacy of the antecedent treatment conferred lasting protection against glucose intolerance when later developing high fat diet (HFD)-induced obesity, with insulin sensitivity persisting for at least 20 weeks of overnutrition. This metabolic resilience was accompanied by healthy epididymal WAT expansion with reduced fibrosis and inflammation. Our findings demonstrate that short-term interventions, without genetic manipulation, can "train" adipose tissue, enhancing its long-term plasticity and conferring durable protection against future obesity-associated insulin resistance.

physiology↗

bioRxiv2023

Pancreatic Deletion of Mitogen-inducible Gene 6 Promotes Beta Cell Proliferation Following Destruction

Type 1 Diabetes (T1D) is caused by autoimmune-mediated beta cell destruction. Following beta cell injury, the pancreas attempts to launch a cellular repair and regenerative program, yet it fails to completely restore functional beta cell mass. One component of this regenerative program is epidermal growth factor receptor (EGFR) signaling. However, upon irreparable beta cell damage, EGFR signaling is dampened, disrupting attempts to restore functional beta cell mass and maintain normoglycemia. We previously demonstrated that the negative feedback inhibitor of EGFR, Mitogen-inducible gene 6 (Mig6), is induced by the pro-inflammatory cytokines central to the autoimmune-mediated beta cell destruction. We also established that pro-inflammatory cytokines suppress EGFR activation, and siRNA-mediated suppression of Mig6 restores EGFR signaling. Thus, we hypothesized that pro-inflammatory cytokines induce nitric oxide production and that in turn induced Mig6, disrupting EGFR repair mechanisms. We determined that NO induces Mig6, attenuating EGFR signaling, and NO synthase inhibition blocks the cytokine-mediated induction of Mig6, thereby restoring cytokine-impaired EGFR signaling. To that end, we treated mice lacking pancreatic Mig6 and control mice with a streptozotocin (STZ) to induce beta cell death and diabetes in a way that mimics the onset and progression of T1D. Whereas STZ-treated control mice became hyperglycemic and had reduced beta cell mass, STZ-treated Mig6 pancreas-specific knock out (PKO) mice remained euglycemic and glucose tolerant due to preserved beta cell mass. The restoration of beta cell mass in PKO mice was accompanied by enhanced beta cell proliferation. Thus, our work suggests that Mig6 is a promising target to preserve beta cell mass before overt T1D.

cell biology↗