What topics does this cannabis study cover?

This study covers research on: Endocannabinoid.

Where was this research published?

Published in Biochemistry and biophysics reports on June 1, 2026.

CB1 receptor not the key to p62-linked obesity

Q: What did this research study find?

This study explored how the protein p62 interacts with the *cannabinoid CB1 receptor* (CB1R) to regulate metabolism and body weight. Researchers found that **CB1R undergoes autophagy-dependent degradation** in neurons, and when autophagy was blocked, CB1R accumulated significantly. However, when the

Exploring cannabinoid receptor CB1 autophagy and the obesity phenotype of p62-deficient mice.

Biochemistry and biophysics reports • June 1, 2026 • Moderately Relevant

🤖

AI Summary

This study explored how the protein p62 interacts with the cannabinoid CB1 receptor (CB1R) to regulate metabolism and body weight. Researchers found that CB1R undergoes autophagy-dependent degradation in neurons, and when autophagy was blocked, CB1R accumulated significantly. However, when they examined p62 knockout mice, p62 deficiency did not alter CB1R levels in the brain or hypothalamus, suggesting p62's role in CB1R turnover may be indirect or limited.

The p62 knockout mice developed interesting metabolic characteristics: late-onset obesity without increased appetite, early hypoactivity, and elevated levels of 2-arachidonoylglycerol (2-AG, an endocannabinoid). Despite these changes and the involvement of CB1R signaling, blocking CB1R with antagonists failed to reverse the obesity or hypoactivity, indicating that the endocannabinoid system is unlikely the primary driver of these metabolic problems in these mice. This suggests the relationship between autophagy, p62, and metabolic dysfunction operates through mechanisms independent of CB1R function.

These findings have important implications for understanding obesity and metabolic regulation. While both the endocannabinoid system and autophagy play roles in metabolism, this research demonstrates they may not directly interact in the way previously hypothesized. This could redirect future therapeutic approaches for obesity away from CB1R antagonists (which faced safety concerns) toward other metabolic pathways, though more research is needed to fully understand how p62 deficiency affects body weight.

📄 Original Abstract

The endocannabinoid system (ECS) and the autophagy receptor p62 are both implicated in metabolic regulation and obesity, yet the mechanisms linking these pathways remain unclear. Here, we investigated whether p62 modulates CB1 receptor (CB1R) turnover or function and whether CB1R contributes to the metabolic phenotype of p62 knockout (KO) mice. In primary cortical neurons from wild-type mice, inhibition of autophagic flux with Bafilomycin A1 led to substantial CB1R accumulation, demonstrating that CB1R is a subject to autophagy-dependent degradation. CB1R agonist stimulation partially reduced this accumulation, suggesting receptor activation influences turnover. In vivo, p62 deficiency did not significantly alter CB1R protein abundance in the brain or hypothalamus, although hypothalamic ERK1/2 signaling downstream of CB1R was modestly attenuated. P62 KO mice displayed late-onset obesity without hyperphagia, early hypoactivity, and elevated hypothalamic 2-arachidonoylglycerol (2-AG) levels with age. Fasting-refeeding experiments revealed reduced food intake in adult and aged, but not juvenile, p62 KO animals. Pharmacological CB1R antagonism did not uncover a direct receptor-dependent mechanism underlying these phenotypes. Together, these findings indicate that, although CB1R undergoes autophagic degradation in neurons, p62 deficiency does not alter steady-state receptor levels and does not directly account for obesity or hypoactivity in p62 KO mice. Within the scope of the experiments performed, CB1R is therefore unlikely to be a primary driver of the metabolic phenotype associated with p62 deficiency.

Paper Type

📄 Research

Publication

Journal: Biochemistry and biophysics reports
Published: June 1, 2026
PMID: 42004545
DOI: 10.1016/j.bbrep.2026.102571

Authors (6)

Christina Keller RG Neuronal and Cellular Signal Transduction, Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, 20246, Germany.
Sebastian Rading RG Neuronal and Cellular Signal Transduction, Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, 20246, Germany.
Bahar Candur RG Neuronal and Cellular Signal Transduction, Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, 20246, Germany.
Laura Bindila Clinical Lipidomics Unit, Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, 55128, Germany.
Gabriele Loers RG Neuronal and Cellular Signal Transduction, Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, Hamburg, 20246, Germany.
+1 more authors