Metabolic Profile of Male Cannabis Users and Estimation of Candidate Biomarkers

Tetrahydrocannabinol (THC), the primary psychoactive compound of cannabis, is the most widely abused substance worldwide, with an annual prevalence of 4.3% of adults and 5.3% of the 15-16 year-old population estimated as of 2022. THC has both acute and chronic effects through the dopaminergic and endocannabinoid systems. This study was conducted to better understand the metabolites and metabolic pathways in biological systems affected by cannabis, which may help find practical diagnostic and treatment approaches for people with cannabis dependence in the future. Metabolomic analysis of urine samples was performed using gas chromatography-mass spectrometry (GC-MS). MetaboAnalyst software was used to determine sample metabolite profiles, which were then subjected to multivariate statistical analysis. From data of over 200 metabolites in each sample of cannabis users, 92 metabolites with a <i>p</i>-value of less than 0.05 were selected for further analyses, of which 38 showed a decrease and 54 showed an increase compared to the nonuser group. Based on 43 metabolites (VIP > 1), subjected to MetaboAnalyst and CPDB, amino acid metabolism (especially arginine, methionine, and cysteine), vitamin metabolism (particularly biotin), and the urea cycle were the primarily affected metabolic pathways. The AUC values of the four metabolites (salsoline, 6-thiourate, procollagen 5-hydroxy-<i>l</i>-lysine, and biotin) with the highest VIP scores were between 0.93 and 0.98, with no significant difference. Metabolites with high VIP scores hold promise as biomarker candidates for identifying cannabis users, and the prominent pathways provide new insights into the understanding of the metabolic effects of cannabis.