In general, the locomotor depressant and discriminative stimulus effects have been observed at doses that do not produce adverse effects, although tremors were observed upon handling in mice that received JWH-210 (Gatch et al., 2016), and 5F-AMB produced sustained vocalization and convulsions in rats (Gatch et al., 2018
A 30-min period, beginning when maximal depression of locomotor activity first appeared as a function of dose, was used for analysis of dose-response data and calculation of ED50 values. During test sessions, both levers were active, such that ten consecutive responses on either lever led to 5CLADBA reinforcement. The substitution tests occurred only if the rats had achieved 85% injection-appropriate responding on the two prior training sessions.
The locomotor activity assay was used to identify approximate time courses and dose ranges of psychoactive effects, which is useful for identifying parameters for drug discrimination experiments and are also predictive of the time course of the psychoactive effects in human users. The purpose of the present study was to assess the abuse liability of 5F-MDMB-PINACA, MDMB-CHIMICA, MDMB-FUBINACA, ADB-FUBINACA, and AMB-FUBINACA. Since there is currently no robust measure of the reinforcing/rewarding effects of cannabinoids, drug discrimination is currently the best model for assessing abuse liability of cannabinoids. The findings produce an apparent paradox, since CPP and self-administration predict with high reliability the likelihood that a compound will be abused by humans, and cannabinoids are well-known to produce active drug-seeking in human
Due to the unknown toxicity of newly emerging SCRAs, forensic assessments of cases involving these substances are challenging. According to the reported cases and reviews of the scientific literature, concurrent ethanol consumption should amplify the toxicity of SCRAs. The concentration of 4F-MDMB-BINACA in the postmortem blood was 2.50 and 2.34 ng/mL, and blood alcohol concentration was 2.11 and 2.49 g/L, respectively. Two fatal cases are reported caused by simultaneous consumption of 4F-MDMB-BINACA and ethanol.
Fig. 2.
The precursor ion m/z 396 (B10, B12/B15) was 32 Da higher than the parent drug, 4F-MDMB-BINACA, suggesting the addition of two hydroxy groups. All the below explanations for transformations into metabolites are based on the data shown in Fig. Metabolites were identified according to their precursor ions, product ions, and fragmentation patterns (Fig. 1). Traditional in-vivo metabolism studies to generate human metabolites of drugs relied heavily on the use of whole animal model systems, which are expensive, limited by drug administration amount, influenced by species variation and faced by many ethical issues. Eight in-vivo metabolites tentatively identified were mainly products of ester hydrolysis with or without additional dehydrogenation, N-dealkylation, monohydroxylation and oxidative defluorination with further oxidation to butanoic acid.
Fig. 1.
Monitoring metabolism of synthetic cannabinoid 4F-MDMB-BINACA via high-resolution mass spectrometry assessed in cultured hepatoma cell line, fungus, 5CLADBA liver microsomes and confirmed using urine samples The threshold for fatal overdose of combined use of SCRAs and ethanol can be estimated as a little ng/mL (0.37–4.1 ng/mL according to the reported cases) of SCRA and 1.5–2.5 g/L of ethanol. The reported cases and reviews of the scientific literature suggest a possible synergistic effect between SCRAs and ethanol, because their combined use clearly increases their toxicity. The victim died due to severe necrotizing pancreatitis and acute kidney injury evolving into multi-organ failure 11 days after hospital admission . Studies have found no unequivocal synergistic effect between THC and ethanol at low or moderate ethanol doses [29, 30], but no data on high doses of ethanol are available. Given that THC and ethanol act on the same receptors, data on their simultaneous use may yield important insights in this regard.
Fungus C. elegans
Methyl (2S)-2-([1-(4-fluorobutyl)-1H-indazole-3-carbonyl]amino)-3,3-dimethylbutanoate (4F-MDMB-BINACA, 4F-MDMB-BUTINACA or 4F-ADB), found in numerous SCB product seizures, has been reported by various law enforcement since 2018 . However, most of the SCBs are full agonists at CB1 and CB2 receptors, having a higher risk of undesirable side effects when compared to THC which is a partial agonist . Synthetic cannabinoids (SCBs) are agonists at cannabinoid receptor type 1 (CB1) and type 2 (CB2), where they elicit their main effect
Although there were reports on the metabolism of 4F-MDMB-BINACA using in-vivo and various in-vitro models, studies were either conducted using small in-vivo sample size such as 1 to 4 samples [5, 29] or in closed environments such as forensic psychiatric wards and prisons . The hepatic cell line HepG2 is often used as an initial screen as it is known to produce high reproducibility results with relatively stable enzyme concentration, although they are limited by the low-level expression of several metabolizing enzymes, including the cytochrome P450 (CYP) class of proteins [17, 18]. In-vitro metabolism studies are generally used to complement these data using perfused organs, tissue or cell cultures and microsomal preparations amongst which pooled human liver microsomes (HLM) have been frequently used to elucidate metabolism of SCBs [12,13,14,15,16]. Since most SCBs are found extensively in metabolized forms in urine, the identification of metabolites is of vital importance for forensic and clinical toxicologists. Identifying SCB intake and its correlating specific adverse effects require rapid elucidation of these SCBs. The proliferation of SCBs has become a global challenge as new compounds are rapidly introduced into the illegal drug market to evade existing drug law
A 30-min period, beginning when maximal depression of locomotor activity first appeared as a function of dose, was used for analysis of dose-response data and calculation of ED50 values. During test sessions, both levers were active, such that ten consecutive responses on either lever led to 5CLADBA reinforcement. The substitution tests occurred only if the rats had achieved 85% injection-appropriate responding on the two prior training sessions.
The locomotor activity assay was used to identify approximate time courses and dose ranges of psychoactive effects, which is useful for identifying parameters for drug discrimination experiments and are also predictive of the time course of the psychoactive effects in human users. The purpose of the present study was to assess the abuse liability of 5F-MDMB-PINACA, MDMB-CHIMICA, MDMB-FUBINACA, ADB-FUBINACA, and AMB-FUBINACA. Since there is currently no robust measure of the reinforcing/rewarding effects of cannabinoids, drug discrimination is currently the best model for assessing abuse liability of cannabinoids. The findings produce an apparent paradox, since CPP and self-administration predict with high reliability the likelihood that a compound will be abused by humans, and cannabinoids are well-known to produce active drug-seeking in human
Due to the unknown toxicity of newly emerging SCRAs, forensic assessments of cases involving these substances are challenging. According to the reported cases and reviews of the scientific literature, concurrent ethanol consumption should amplify the toxicity of SCRAs. The concentration of 4F-MDMB-BINACA in the postmortem blood was 2.50 and 2.34 ng/mL, and blood alcohol concentration was 2.11 and 2.49 g/L, respectively. Two fatal cases are reported caused by simultaneous consumption of 4F-MDMB-BINACA and ethanol.
Fig. 2.
The precursor ion m/z 396 (B10, B12/B15) was 32 Da higher than the parent drug, 4F-MDMB-BINACA, suggesting the addition of two hydroxy groups. All the below explanations for transformations into metabolites are based on the data shown in Fig. Metabolites were identified according to their precursor ions, product ions, and fragmentation patterns (Fig. 1). Traditional in-vivo metabolism studies to generate human metabolites of drugs relied heavily on the use of whole animal model systems, which are expensive, limited by drug administration amount, influenced by species variation and faced by many ethical issues. Eight in-vivo metabolites tentatively identified were mainly products of ester hydrolysis with or without additional dehydrogenation, N-dealkylation, monohydroxylation and oxidative defluorination with further oxidation to butanoic acid.
Fig. 1.
Monitoring metabolism of synthetic cannabinoid 4F-MDMB-BINACA via high-resolution mass spectrometry assessed in cultured hepatoma cell line, fungus, 5CLADBA liver microsomes and confirmed using urine samples The threshold for fatal overdose of combined use of SCRAs and ethanol can be estimated as a little ng/mL (0.37–4.1 ng/mL according to the reported cases) of SCRA and 1.5–2.5 g/L of ethanol. The reported cases and reviews of the scientific literature suggest a possible synergistic effect between SCRAs and ethanol, because their combined use clearly increases their toxicity. The victim died due to severe necrotizing pancreatitis and acute kidney injury evolving into multi-organ failure 11 days after hospital admission . Studies have found no unequivocal synergistic effect between THC and ethanol at low or moderate ethanol doses [29, 30], but no data on high doses of ethanol are available. Given that THC and ethanol act on the same receptors, data on their simultaneous use may yield important insights in this regard.
Fungus C. elegans
Methyl (2S)-2-([1-(4-fluorobutyl)-1H-indazole-3-carbonyl]amino)-3,3-dimethylbutanoate (4F-MDMB-BINACA, 4F-MDMB-BUTINACA or 4F-ADB), found in numerous SCB product seizures, has been reported by various law enforcement since 2018 . However, most of the SCBs are full agonists at CB1 and CB2 receptors, having a higher risk of undesirable side effects when compared to THC which is a partial agonist . Synthetic cannabinoids (SCBs) are agonists at cannabinoid receptor type 1 (CB1) and type 2 (CB2), where they elicit their main effect
Although there were reports on the metabolism of 4F-MDMB-BINACA using in-vivo and various in-vitro models, studies were either conducted using small in-vivo sample size such as 1 to 4 samples [5, 29] or in closed environments such as forensic psychiatric wards and prisons . The hepatic cell line HepG2 is often used as an initial screen as it is known to produce high reproducibility results with relatively stable enzyme concentration, although they are limited by the low-level expression of several metabolizing enzymes, including the cytochrome P450 (CYP) class of proteins [17, 18]. In-vitro metabolism studies are generally used to complement these data using perfused organs, tissue or cell cultures and microsomal preparations amongst which pooled human liver microsomes (HLM) have been frequently used to elucidate metabolism of SCBs [12,13,14,15,16]. Since most SCBs are found extensively in metabolized forms in urine, the identification of metabolites is of vital importance for forensic and clinical toxicologists. Identifying SCB intake and its correlating specific adverse effects require rapid elucidation of these SCBs. The proliferation of SCBs has become a global challenge as new compounds are rapidly introduced into the illegal drug market to evade existing drug law
