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BackgroundThe transient receptor potential vanilloid 1 (TRPV1) participates in thermosensation and inflammatory pain, but its immunomodulatory mechanisms remain enigmatic. N-Oleoyl dopamine (OLDA), an endovanilloid and endocannabinoid, is a TRPV1 agonist that is produced in the central nervous system and the peripheral nervous system. We studied the anti-inflammatory effects and TRPV1-dependent mechanisms of OLDA in models of inflammation and sepsis.MethodsMice were challenged intratracheally or intravenously with LPS, or intratracheally with S. aureus to induce pneumonia and sepsis, and then were treated intravenously with OLDA. Endpoints included plasma cytokines, leukocyte activation marker expression, mouse sepsis scores, lung histopathology, and bacterial counts. The role of TRPV1 in the effects of OLDA was determined using Trpv1-/- mice, and mice with TRPV1 knockdown pan-neuronally, in peripheral nervous system neurons, or in myeloid cells. Circulating monocytes/macrophages were depleted using clodronate to determine their role in the anti-inflammatory effects of OLDA in endotoxemic mice. Levels of exogenous OLDA, and of endovanilloids and endocannabinoids, at baseline and in endotoxemic mice, were determined by LC-MS/MS.ResultsOLDA administration caused an early anti-inflammatory response in endotoxemic and septic mice with high serum levels of IL-10 and decreased levels of pro-inflammatory cytokines. OLDA also reduced lung injury and improved mouse sepsis scores. Blood and lung bacterial counts were comparable between OLDA- and carrier-treated mice with S. aureus pneumonia. OLDA's effects were reversed in mice with pan-neuronal TRPV1 knockdown, but not with TRPV1 knockdown in peripheral nervous system neurons or myeloid cells. Depletion of monocytes/macrophages reversed the IL-10 upregulation by OLDA in endotoxemic mice. Brain and blood levels of endovanilloids and endocannabinoids were increased in endotoxemic mice.ConclusionsOLDA has strong anti-inflammatory actions in mice with endotoxemia or S. aureus pneumonia. Prior studies focused on the role of peripheral nervous system TRPV1 in modulating inflammation and pneumonia. Our results suggest that TRPV1-expressing central nervous system neurons also regulate inflammatory responses to endotoxemia and infection. Our study reveals a neuro-immune reflex that during acute inflammation is engaged proximally by OLDA acting on neuronal TRPV1, and through a multicellular network that requires circulating monocytes/macrophages, leads to the systemic production of IL-10.

The public is increasingly reporting using cannabis for anxiety relief. Both cannabis use and the endocannabinoid system have been connected with anxiety relief/anxiolytic properties, but these relationships are complex, and the underlying mechanisms for them are unclear. Background/Objectives: Work is needed to understand how the endocannabinoid system, including the endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol (2-AG), may be impacted by the main constituents of cannabis, Δ9-tetrahydrocannabinol (THC), and cannabidiol (CBD). Methods: The current study examined how the ab libitum use of products differing in THC and CBD affected AEA and 2-AG among 292 individuals randomly assigned to THC-dominant use (N = 92), CBD-dominant use (N = 97), THC + CBD use (N = 74), or non-use (N = 29). Results: The findings suggest that AEA levels do not change differently based on 4 weeks of cannabis use or by cannabinoid content, as AEA similarly increased across all conditions from study weeks 2 to 4. In contrast, AEA decreased at an acute administration session with product conditions containing any THC having greater AEA levels on average than the non-use condition. With regard to 2-AG, its levels appeared to primarily be affected by THC-dominant use, both acutely and over 4 weeks, when controlling for baseline cannabis use and examining study product use frequency among use conditions. Conclusions: Overall, the results continue to shed light on the complicated relationship between cannabinoid content and endocannabinoid production, and highlight the need for continued research on their interplay in human subjects. [ABSTRACT FROM AUTHOR]

In recent years, potential therapeutic applications of several different cannabinoids, such as Δ9-tetrahydrocannabinol (Δ9-THC), its isomer Δ8-THC and Δ9-tetrahydrocannabivarin (Δ9-THCV), have been investigated. Nevertheless, to establish dose–effect relationship and to gain knowledge of their pharmacokinetics and metabolism, sensitive and specific analytical assays are needed to measure these compounds in patients. For this reason, we developed and validated an online extraction high-performance liquid/liquid chromatography–tandem mass spectrometry (LC/LC–MS-MS) method for the simultaneous quantification of 13 cannabinoids and metabolites including the Δ8 and Δ9 isomers of THC, THCV and those of their major metabolites in human plasma. Plasma was fortified with cannabinoids at varying concentrations within the working range of the respective compound and 200 µL was extracted using a simple one-step protein precipitation procedure. The extracts were analyzed using online trapping LC/LC–atmospheric pressure chemical ionization–MS-MS running in the positive multiple reaction monitoring mode. The lower limit of quantification ranged from 0.5 to 2.5 ng/mL, and the upper limit of quantification was 400 ng/mL for all analytes. Inter-day analytical accuracy and imprecision ranged from 82.9% to 109% and 4.3% to 20.3% (coefficient of variance), respectively. Of 534 plasma samples following controlled oral administration of Δ8-THCV, 236 were positive for Δ8-THCV (median; interquartile ranges: 3.5 ng/mL; 1.8–11.9 ng/mL), 383 for the major metabolite (−)-11-nor-9-carboxy-Δ8-tetrahydrocannabivarin (Δ8-THCV-COOH) (95.4 ng/mL; 20.7–328 ng/mL), 260 for (−)-11-nor-9-carboxy-Δ9-tetrahydrocannabivarin (Δ9-THCV-COOH) (5.8 ng/mL; 2.5–16.1 ng/mL), 157 for (−)-11-hydroxy-Δ8-tetrahydrocannabivarin (11-OH-Δ8-THCV) (1.7 ng/mL; 1.0–3.7 ng/mL), 49 for Δ8-THC-COOH (1.7 ng/mL; 1.4–2.3 ng/mL) and 42 for Δ9-THCV (1.3 ng/mL; 0.8–1.6 ng/mL). We developed and validated the first LC/LC–MS-MS assay for the specific quantification of Δ8-THC, Δ9-THC and THCV isomers and their respective metabolites in human plasma. Δ8-THCV-COOH, 11-hydroxy-Δ8-THCV and Δ9-THCV-COOH were the major Δ8-THCV metabolites in human plasma after oral administration of 98.6% pure Δ8-THCV. [ABSTRACT FROM AUTHOR]

Urine is a common matrix for screening for cannabis use. Urine assays typically measure total 11‐nor‐9‐carboxy‐Δ9‐tetrahydrocannabinol (THCCOOH) concentrations after hydrolysis cleaves the glucuronide. Urine THCCOOH concentration is adjusted by urine creatinine concentration or specific gravity, to account for variable hydration states. Therefore, we performed a population pharmacokinetic analysis of the urinary THCCOOH excretion, urinary flow rate, and creatinine excretion rate data. Urine was obtained over 168 h from six subjects who smoked low‐ (15.8 mg) and high‐dose (33.8 mg) Δ9‐tetrahydrocannabinol (THC) cigarettes on two occasions. Samples were analyzed for THCCOOH concentration by gas chromatography–mass spectrometry (GC‐MS) and volume, time, and creatinine concentration measured. A population pharmacokinetic model of the urinary clearance of THCCOOH was created from these data, and potential covariates of urine creatinine concentration and urine creatinine excretion rate were assessed. Elimination clearance of THCCOOH was estimated as 0.104 ± 0.088 L/min, and its urinary clearance was 0.0022 ± 0.0015 L/min. Total urine excretion of THCCOOH was estimated at 2.3%. Urine flow rate and urine creatinine concentrations were significantly correlated, r2 = 0.35. Creatinine excretion rate was 129.6 ± 71.0 ml/min, and the intrasubject variability was 31%–52% (SD%) during the week. Urinary creatinine excretion rate was a significant covariate for the urinary clearance of THCCOOH. Creatinine clearance is a significant covariate for urinary THCCOOH clearance. Only 2%–3% of bioavailable THC is excreted as THCCOOH and THCCOO‐glucuronide via the urine. Correction of urine drug and/or metabolite concentration with urine creatinine concentration or specific gravity may be more problematic than previously appreciated. [ABSTRACT FROM AUTHOR]