Autophagy couteracts weight gain, lipotoxicity and pancreatic β-cell death upon hypercaloric pro-diabetic regimens.
Level 5 - mechanism / opinion, no new human data
Bench and animal research with no human data
PubMed 28771229 · doi:10.1038/cddis.2017.373
What was done
Mice were evaluated under starvation, hypercaloric pro-diabetic regimens, and acute streptozotocin challenge. Investigators used genetic (Atg4b-deficient mice) and pharmacological inhibition of autophagy, as well as pharmacological stimulation of autophagy with spermidine in wild-type mice, measuring body weight changes, visceral adipocyte size, hepatic steatosis, glucose tolerance, and insulin response.
What was found
No numerical values, sample sizes, or effect sizes were reported in the abstract. Directionally, both genetic and pharmacological inhibition of autophagy compromised starvation-induced weight loss. In hypercaloric regimens, Atg4b-deficient mice had increased body weight gain, larger visceral adipocytes, increased hepatic steatosis, reduced glucose tolerance, and attenuated insulin responses. Autophagy-deficient mice also had increased vulnerability to streptozotocin-induced type-1 diabetes. Pharmacological stimulation of autophagy with spermidine reduced weight gain and metabolic alterations in wild-type mice on hypercaloric regimens.
Why it matters
This study shows that intact systemic autophagic capacity is required to buffer against diet-induced obesity, hepatic steatosis, and beta-cell loss in mice, identifying autophagy up-regulation as a potential metabolic target.
Limits
All findings are derived exclusively from mouse models with no human validation. The abstract omits sample sizes, specific drug dosages, durations of dietary interventions, and exact numerical outcomes or variance statistics.
Cited by
- supports Administering spermidine to mice fed a high-fat diet reduces weight gain.