Fig. 2.
Our findings revealed that both victims consumed large amounts of alcohol preceding their deaths (blood alcohol concentrations (BAC) were 2.11 and 2.49 g/L, respectively). Forensic autopsy of both victims was performed four days after the time of death following the Recommendation No.R (99)3 of the Council of Europe on medico-legal autopsies. Elegans demonstrated the ability to form all of the in-vivo metabolites and has the potential to be used as a complementary model to predict and characterize human metabolites, as well as identifying possible drug toxicities for emerging SCBs. Thus, identification of the relevant urinary markers was based primarily upon the prevalence of the in-vivo metabolites instead of the metabolites ranking that was based upon % peak area abundance ratio. Moreover, genetic makeup, physiological conditions (age, gender 4F ADB and ethnicity), environmental influences (diet) and pathological factors (liver diseases, diabetes, and obesity) would further complicate the metabolism of drugs. It should be noted that % peak area abundance ratios do not necessarily reflect absolute concentrations due to differences in ionization capacity and matrix effects bias for each metabolite.
Data concerning the combined effects of SCRAs and other substances are highly limited, which renders forensic evaluation of possible overdose cases difficult . The threshold SCRA concentration for fatal overdose can be estimated ng/mL level (0.37–4.1 ng/mL according to the reported cases) in cases in which 1.5–2.5 g/L of ethanol is present in the blood. The victims were brothers who were both found deceased after consuming 4F-MDMB-BINACA and ethanol. These confusing shorter names were not scientifically adopted but were used by websites selling the drugs to the public. Monitoring metabolism of synthetic cannabinoid 4F-MDMB-BINACA via high-resolution mass spectrometry assessed in cultured hepatoma cell line, fungus, liver microsomes and confirmed using urine samples. This article does not contain any studies with human participants or animals performed by any of the author
Locomotor activity in mice was tested to screen for locomotor depressant effects and to identify behaviorally-active dose ranges and times of peak effect. Previous studies have demonstrated that these compounds have chemical structures similar to synthetic cannabinoids known to have substantial abuse liability and act at the CB1 receptor. Tremors were not observed following AMB-FUBINACA during the drug discrimination study, but the maximum dose tested was only 0.1 mg/kg, which is 10-fold lower than the dose that produced tremors in the mice. AMB-FUBINACA has been implicated in severe adverse effects in recreational users (Adams et al., 2017; Hamilton et al., 2017), which suggests that the range between behaviorally active and toxic doses of AMB-FUBINACA is narrow. Following that line of reasoning, it should also be noted that some of the more recent compounds produced non-linear dose-effect curves and one compound produced an inverted U-shaped dose-effect, such that intermediate dose fully substituted, but higher doses did not (Gatch and Forster, 2018). All of the compounds identified as available on the recreational market and submitted to our laboratory by the US Drug Enforcement Agency for testing have fully substituted at some dose (Gatch and Forster 2014, 2015, 2016, 2018); however; it is important to note that not all structural congeners are active (Wiley et al., 2012
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
Figure 1.
Each training session lasted a maximum of 10 min, and the rats could earn up to 20 food pellets. Thirty minutes prior to the training sessions, rats received an injection of either vehicle or Δ9-THC and were subsequently placed in the behavior-testing chambers, where food (45-mg food pellets; Bio-Serve, Frenchtown, NJ) was available as a reinforcer for every ten responses (FR10) on a designated injection appropriate lever. A houselight was centered over the hopper close to the ceiling and was illuminated only when the levers were active. Each dose range included doses that were without effect to those producing at least 50% depression compared to vehicle control. Twenty-four male Sprague-Dawley rats were obtained from Envigo (Houston, TX). Male ND4 Swiss–Webster mice were obtained from Envigo (Houston, TX) at approximately 8 weeks of age and maintained in the University of North Texas Health Science Center (UNTHSC) animal facility for two weeks prior to testin
Product ions detected at m/z 302, 217, and 145 (B2) confirmed that tert-leucine and indazole moieties remained unchanged, leading to the structure elucidation of a hydroxy-functional group at the 4-position of the butyl side chain by oxidative defluorination. The product ion m/z 336 (loss of methyl ester moiety) further confirmed the presence of dihydroxylated metabolites. The precursor ion, m/z 364 (B14, B5/B6) had a loss of 2 Da from m/z 366 indicated further dehydrogenation of the ester hydrolysis plus monohydroxylated metabolites. The presence of the product ion m/z 320, likely formed from a loss of carbon dioxide, indicated monohydroxylation at the tert-leucine in B8 (m/z 219), butyl side chain in B9 (m/z 145) and indazole moiety in B13 (m/z 161). The precursor ion, m/z 350 showed a loss of 14 Da explaining the hydrolysis of methyl ester from 4F-MDMB-BINACA.
Fig. 2.
4F-MDMB-BINACA was hydrolysed via ester hydrolysis forming the 4F-MDMB-BINACA ester hydrolysis metabolite (B22). Data obtained from the twenty urine samples were retrospectively analysed and processed using TraceFinder software based on the identification criteria of mass errors less than ± 5 ppm for full MS peaks and MS/MS peaks from the theoretical mass and matching of MS/MS spectra. The mixture was vortex-mixed and 500 µL of this mixture and 500 µL of methanol were loaded onto the Clean Screen FASt® tube. After incubation, the mixture was cooled at room temperature, and 150 µL of purified water was added. High-resolution QTOF-MS data were acquired on an Agilent 6510 Accurate Mass QTOF mass spectrometer (Agilent Technologies) equipped with dual electrospray ionization (ESI) source operated in both positive and negative ion modes, to determine accurate masses of the metabolites. Chromatographic separation was performed on an Agilent 1290 LC system with a Poroshell 120 EC-C18 analytical column (2.7 μm, 75 × 2.1 mm; Agilent Technologies, Santa Clara, CA, USA).
Fig. 1.
This outcome was anticipated since CES-mediated hydrolysis is commonly 4F ADB reported as the major metabolic pathway among the SCBs impacting the terminal ester group . Glucosides and sulfate metabolites have been reported with other SCBs where C. From these three samples, sample 2 contained only an ester hydrolysis metabolite (m/z 350). Both ester hydrolysis followed by oxidative defluorination to butanoic acid (B4, m/z 362) and monohydroxylation at tert-leucine moiety (B8, m/z 366) metabolites were found in 16/20 urine samples (Table 2). A In-vitro metabolites observed in common among respective seven most abundant metabolites in b C. The product ion detected at m/z 235, indicating loss of sulfate, confirmed the identity of the sulfation metabolite.
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
Our findings revealed that both victims consumed large amounts of alcohol preceding their deaths (blood alcohol concentrations (BAC) were 2.11 and 2.49 g/L, respectively). Forensic autopsy of both victims was performed four days after the time of death following the Recommendation No.R (99)3 of the Council of Europe on medico-legal autopsies. Elegans demonstrated the ability to form all of the in-vivo metabolites and has the potential to be used as a complementary model to predict and characterize human metabolites, as well as identifying possible drug toxicities for emerging SCBs. Thus, identification of the relevant urinary markers was based primarily upon the prevalence of the in-vivo metabolites instead of the metabolites ranking that was based upon % peak area abundance ratio. Moreover, genetic makeup, physiological conditions (age, gender 4F ADB and ethnicity), environmental influences (diet) and pathological factors (liver diseases, diabetes, and obesity) would further complicate the metabolism of drugs. It should be noted that % peak area abundance ratios do not necessarily reflect absolute concentrations due to differences in ionization capacity and matrix effects bias for each metabolite.
Data concerning the combined effects of SCRAs and other substances are highly limited, which renders forensic evaluation of possible overdose cases difficult . The threshold SCRA concentration for fatal overdose can be estimated ng/mL level (0.37–4.1 ng/mL according to the reported cases) in cases in which 1.5–2.5 g/L of ethanol is present in the blood. The victims were brothers who were both found deceased after consuming 4F-MDMB-BINACA and ethanol. These confusing shorter names were not scientifically adopted but were used by websites selling the drugs to the public. Monitoring metabolism of synthetic cannabinoid 4F-MDMB-BINACA via high-resolution mass spectrometry assessed in cultured hepatoma cell line, fungus, liver microsomes and confirmed using urine samples. This article does not contain any studies with human participants or animals performed by any of the author
Locomotor activity in mice was tested to screen for locomotor depressant effects and to identify behaviorally-active dose ranges and times of peak effect. Previous studies have demonstrated that these compounds have chemical structures similar to synthetic cannabinoids known to have substantial abuse liability and act at the CB1 receptor. Tremors were not observed following AMB-FUBINACA during the drug discrimination study, but the maximum dose tested was only 0.1 mg/kg, which is 10-fold lower than the dose that produced tremors in the mice. AMB-FUBINACA has been implicated in severe adverse effects in recreational users (Adams et al., 2017; Hamilton et al., 2017), which suggests that the range between behaviorally active and toxic doses of AMB-FUBINACA is narrow. Following that line of reasoning, it should also be noted that some of the more recent compounds produced non-linear dose-effect curves and one compound produced an inverted U-shaped dose-effect, such that intermediate dose fully substituted, but higher doses did not (Gatch and Forster, 2018). All of the compounds identified as available on the recreational market and submitted to our laboratory by the US Drug Enforcement Agency for testing have fully substituted at some dose (Gatch and Forster 2014, 2015, 2016, 2018); however; it is important to note that not all structural congeners are active (Wiley et al., 2012
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
Figure 1.
Each training session lasted a maximum of 10 min, and the rats could earn up to 20 food pellets. Thirty minutes prior to the training sessions, rats received an injection of either vehicle or Δ9-THC and were subsequently placed in the behavior-testing chambers, where food (45-mg food pellets; Bio-Serve, Frenchtown, NJ) was available as a reinforcer for every ten responses (FR10) on a designated injection appropriate lever. A houselight was centered over the hopper close to the ceiling and was illuminated only when the levers were active. Each dose range included doses that were without effect to those producing at least 50% depression compared to vehicle control. Twenty-four male Sprague-Dawley rats were obtained from Envigo (Houston, TX). Male ND4 Swiss–Webster mice were obtained from Envigo (Houston, TX) at approximately 8 weeks of age and maintained in the University of North Texas Health Science Center (UNTHSC) animal facility for two weeks prior to testin
Product ions detected at m/z 302, 217, and 145 (B2) confirmed that tert-leucine and indazole moieties remained unchanged, leading to the structure elucidation of a hydroxy-functional group at the 4-position of the butyl side chain by oxidative defluorination. The product ion m/z 336 (loss of methyl ester moiety) further confirmed the presence of dihydroxylated metabolites. The precursor ion, m/z 364 (B14, B5/B6) had a loss of 2 Da from m/z 366 indicated further dehydrogenation of the ester hydrolysis plus monohydroxylated metabolites. The presence of the product ion m/z 320, likely formed from a loss of carbon dioxide, indicated monohydroxylation at the tert-leucine in B8 (m/z 219), butyl side chain in B9 (m/z 145) and indazole moiety in B13 (m/z 161). The precursor ion, m/z 350 showed a loss of 14 Da explaining the hydrolysis of methyl ester from 4F-MDMB-BINACA.
Fig. 2.
4F-MDMB-BINACA was hydrolysed via ester hydrolysis forming the 4F-MDMB-BINACA ester hydrolysis metabolite (B22). Data obtained from the twenty urine samples were retrospectively analysed and processed using TraceFinder software based on the identification criteria of mass errors less than ± 5 ppm for full MS peaks and MS/MS peaks from the theoretical mass and matching of MS/MS spectra. The mixture was vortex-mixed and 500 µL of this mixture and 500 µL of methanol were loaded onto the Clean Screen FASt® tube. After incubation, the mixture was cooled at room temperature, and 150 µL of purified water was added. High-resolution QTOF-MS data were acquired on an Agilent 6510 Accurate Mass QTOF mass spectrometer (Agilent Technologies) equipped with dual electrospray ionization (ESI) source operated in both positive and negative ion modes, to determine accurate masses of the metabolites. Chromatographic separation was performed on an Agilent 1290 LC system with a Poroshell 120 EC-C18 analytical column (2.7 μm, 75 × 2.1 mm; Agilent Technologies, Santa Clara, CA, USA).
Fig. 1.
This outcome was anticipated since CES-mediated hydrolysis is commonly 4F ADB reported as the major metabolic pathway among the SCBs impacting the terminal ester group . Glucosides and sulfate metabolites have been reported with other SCBs where C. From these three samples, sample 2 contained only an ester hydrolysis metabolite (m/z 350). Both ester hydrolysis followed by oxidative defluorination to butanoic acid (B4, m/z 362) and monohydroxylation at tert-leucine moiety (B8, m/z 366) metabolites were found in 16/20 urine samples (Table 2). A In-vitro metabolites observed in common among respective seven most abundant metabolites in b C. The product ion detected at m/z 235, indicating loss of sulfate, confirmed the identity of the sulfation metabolite.
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
