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Updated: Jun 23, 2026

Measuring the Rate of Lipolysis in Ex Vivo Murine Adipose Tissue and Primary Preadipocytes Differentiated In Vitro
Published on: March 17, 2023
Ambra1 is essential for fasting-induced lipolysis via ATGL translocation to lipid droplets
Tomohiro Kashikawa1, Hisako Akatsuka2, Takahiro Suzuki3
1Division of Host Defense Mechanism, Tokai University School of Medicine, Isehara, Kanagawa, 259-1193, Japan.
Abstract:
Ambra1, a key regulator of protein homeostasis, controls both autophagy and ubiquitin-mediated proteasomal degradation. Although Ambra1 is implicated in metabolic regulation, its role in adipose tissue homeostasis remains unclear. In this study, Ambra1 conditional knockout mice exhibited impaired fasting-induced weight loss in white adipose tissue. Ambra1-deficient adipocytes exhibited defective lipolysis, accompanied by impaired translocation of adipose triglyceride lipase (ATGL), the rate-limiting lipolytic enzyme, to the surface of lipid droplets. However, ATGL translocation was restored by the inhibition of phosphodiesterase 3B, which antagonizes lipolysis by reducing protein kinase A activity. Collectively, these findings suggest that Ambra1 plays an important role in fasting-induced lipolysis via phosphodiesterase 3B-mediated ATGL control.
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