Bosquez-Berger, T. | Search bioRxiv

bioRxiv2025

Acetaminophen inhibits diacylglycerol lipase synthesis of 2-arachidonoyl glycerol: implications for nociception

SUMMARYThough acetaminophen is a ubiquitous analgesic, its mechanism of action remains unknown. Thus, even though acetaminophen causes ∼500 deaths each year in the US it has not been possible to design safer alternatives. Because endocannabinoids may have a role in acetaminophen action, we examined interactions between the two. We now report that acetaminophen inhibits the activity of diacylglycerol lipase α (DAGLα), but not DAGLβ, decreasing production of the endocannabinoid 2-arachidonoyl glycerol. This gave rise to the counterintuitive hypothesis that decreasing endocannabinoid production by DAGLαinhibitionmay be antinociceptive in certain settings. Supporting this hypothesis, we find that DAGL inhibition by RHC80267 is antinociceptive in wildtype but not CB1 knockout mice in the hotplate test. We propose 1) that activation of DAGLα may exacerbate some forms of nociception and 2) a novel mechanism for the antinociceptive actions of acetaminophen whereby acetaminophen inhibits a DAGLα/CB1-based circuit that plays a permissive role in at least one form of nociception.

neuroscience↗

bioRxiv2023

Plasma and liver lipids are differentially regulated after cannabinoid treatments in male and female mice

Cannabinoids (CBs) have sex-dependent behavioral and physiological effects and modulate lipids across the body. To understand how some of these sex differences may be due to differences how both phyto- and endocannabinoids are regulated in the liver and plasma, male and female CD1 mice were administered 10 mg/kg i.p. of cannabidiol (CBD), {Delta}9-tetrahydrocannabinol (THC), or THC+CBD then core blood and liver tissue were collected after 2 hours. Lipids were extracted from both liver and plasma, and samples were screened via HPLC/MS/MS for {Delta}9-tetrahydrocannabinol (THC), metabolites 11-OH-THC and 11-COOH-THC, cannabidiol (CBD), metabolites 7-OH-CBD and 7-COOH-CBD, ~70 endolipids including the endocannabinoids, N-arachidonoyl ethanolamine (Anandamide; AEA) and 2-sn-arachidonoyl glycerol (2-AG). Structural analogs to AEA (e.g. lipoamino acids, lipoamines) and 2-acyl glycerols) as well as free fatty acids and prostaglandins were also evaluated. Results show that at 2 hours post injection levels of CBs demonstrate key differences between males and females in both plasma and liver, and that these differences vary when co-administered as opposed to administered alone. Illustrating a link between liver and plasma, directionality of CB differences are similar between the two tissue types as a function of both sex and CB treatment. By contrast, endolipids had very different profiles as a function of sex, CB administration, and tissue type. Importantly, there are baseline differences between male and female mice in endocannabinoids and related lipids, which likely impact how CB administration modulates these endolipids. These data illustrate the complexity of outcomes of CB treatment between males and females on circulating CBs and endolipids and highlight the need to consider these factors when evaluating efficacy of CB drug treatments or usage.

pharmacology and toxicology↗