Synthetic cannabinoids (SCBs), designer drugs marketed as legal alternatives to marijuana, act as ligands to cannabinoid receptors; however, they have increased binding affinity and potency, resulting in toxicity symptoms such as cardiovascular incidents, seizures, and potentially death. N-(adamantan-1-yl)-1-(5-fluoropentyl)-1H-indole-3-carboxamide (STS-135) is a third generation SCB. When incubated with hepatocytes, it undergoes oxidation, hydrolysis, and glucuronidation, resulting in 29 metabolites, with monohydroxy STS-135 (M25) and dihydroxy STS-135 (M21) being the predominant metabolites. The enzymes responsible for this oxidative metabolism were unknown. Thus, the aim of this study was to identify the cytochrome P450 (P450s or CYPs) enzymes involved in the oxidative metabolism of STS-135. In this study, STS-135 was incubated with liver, intestinal, and brain microsomes and recombinant P450s to determine the enzymes involved in its metabolism. Metabolite quantification was carried out using ultra-performance liquid chromatography. STS-135 was extensively metabolized in HLMs and HIMs. Screening assays indicated CYP3A4 and CYP3A5 could be responsible for STS-135's oxidation. Through incubations with genotyped HLMs, CYP3A4 was identified as the primary oxidative enzyme. Interestingly, CYP2J2, a P450 isoform expressed in cardiovascular tissues, showed high activity towards the formation of M25 with a Km value of 11.4 μmol/L. Thus, it was concluded that STS-135 was primarily metabolized by CYP3A4 but may have extrahepatic metabolic pathways as well. Upon exposure to STS-135, individuals with low CYP3A4 activity could retain elevated blood concentration, resulting in toxicity. Additionally, CYP2J2 may aid in protecting against STS-135-induced cardiovascular toxicity.

中文翻译：

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鉴定参与合成大麻素 N-(金刚烷-1-基)-1-(5-氟戊基)-1H-吲哚-3-甲酰胺 (STS-135) 氧化代谢的细胞色素 P450。


合成大麻素 (SCB) 是作为大麻合法替代品销售的设计药物，充当大麻素受体的配体；然而，它们的结合亲和力和效力增加，导致毒性症状，如心血管事件、癫痫发作和潜在的死亡。 N-(金刚烷-1-基)-1-(5-氟戊基)-1H-吲哚-3-甲酰胺 (STS-135) 是第三代 SCB。当与肝细胞一起孵育时，它会发生氧化、水解和葡萄糖醛酸化，产生 29 种代谢物，其中单羟基 STS-135 (M25) 和二羟基 STS-135 (M21) 是主要代谢物。负责这种氧化代谢的酶尚不清楚。因此，本研究的目的是鉴定参与 STS-135 氧化代谢的细胞色素 P450（P450s 或 CYPs）酶。在这项研究中，STS-135 与肝脏、肠道和脑微粒体以及重组 P450 一起孵育，以确定参与其代谢的酶。使用超高效液相色谱法进行代谢物定量。 STS-135 在 HLM 和 HIM 中广泛代谢。筛选分析表明 CYP3A4 和 CYP3A5 可能负责 STS-135 的氧化。通过与基因型 HLM 一起孵育，CYP3A4 被确定为主要氧化酶。有趣的是，CYP2J2（一种在心血管组织中表达的 P450 亚型）对 M25 的形成表现出高活性，Km 值为 11.4 μmol/L。因此，得出的结论是，STS-135 主要通过 CYP3A4 代谢，但也可能具有肝外代谢途径。暴露于 STS-135 后，CYP3A4 活性低的个体可能会保持升高的血液浓度，从而导致毒性。此外，CYP2J2 可能有助于防止 STS-135 诱导的心血管毒性。