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bioRxiv · 10.1101/2023.07.31.551241

Restoring adiponectin via rosiglitazone ameliorates tissue wasting in mice with lung cancer.

Abstract

The cancer associated cachexia syndrome (CACS) is a systemic metabolic disorder resulting in loss of body weight due to skeletal muscle and adipose tissues atrophy. CACS is particularly prominent in lung cancer patients, where it contributes to poor quality of life and excess mortality. Using the Kras/Lkb1 (KL) mouse model, we found that CACS is associated with white adipose tissue (WAT) dysfunction that directly affects skeletal muscle homeostasis. WAT transcriptomes showed evidence of reduced adipogenesis, and, in agreement, we found low levels of circulating adiponectin. To preserve adipogenesis and restore adiponectin levels, we treated mice with the PPAR-{gamma} agonist, rosiglitazone. Rosiglitazone treatment increased serum adiponectin levels, delayed weight loss, and preserved skeletal muscle and adipose tissue mass, as compared to vehicle-treated mice. The preservation of muscle mass with rosiglitazone was associated with increases in AMPK and AKT activity. Similarly, activation of the adiponectin receptors in muscle cells increased AMPK activity, anabolic signaling, and protein synthesis. Our data suggest that PPAR-{gamma} agonists may be a useful adjuvant therapy to preserve tissue mass in lung cancer. Key points- The PPAR-{gamma} agonist, rosiglitazone, restores circulating adiponectin levels in mice with lung cancer. - Rosiglitazone preserves skeletal muscle and adipose tissue mass in mice with lung cancer. - The preservation of muscle mass with rosiglitazone is associated with increases in AMPK and AKT activity. - Stimulation of adiponectin signaling increases AMPK activity, anabolic signaling, and protein synthesis in muscle cell culture.

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BibTeXRIS

Langer, H. T., Ramsamooj, S., Dantas, E., Murthy, A., Ahmed, M., Hwang, S.-K., Grover, R., Pozovskiy, R., Liang, R. J., Queiroz, A. L., Brown, J. C., White, E. P., Janowitz, T., Goncalves, M. D.. 2023-08-02. Restoring adiponectin via rosiglitazone ameliorates tissue wasting in mice with lung cancer.. https://doi.org/10.1101/2023.07.31.551241

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