In Vitro Activation of Human Adrenergic Receptors and Trace Amine-Associated Receptor 1 by Phenethylamine Analogues Present in Food Supplements

Synergistic cardiotoxic effects of captagon and azithromycin in rat via oxidative stress, apoptosis and upregulation of the PI3K/AKT/NF-kB pathway

Fenethylline (Captagon) is a blend of amphetamine and theophylline that functions as a stimulant, while azithromycin (AZ) is a commonly prescribed macrolide antibiotic. The co-usage of illicit substances and therapeutic drugs can result in substantial health risk especially cardiotoxicity. This study aimed to assess cardiotoxicity effects of Captagon (Capta) and Azithromycin/Captagon interaction in adult male rats. Forty-two animals were assigned into 6 groups: Group I (Control) and group II (AZ (30 mg/kg/day) starting from the 14th day of the experiment and for 2 weeks. Group III (Capta10 mg/kg/day), group IV (Capta20 mg/kg/day), group V (AZ+Capta10) and group VI (AZ+Capta20) daily 28 days. Electrocardiogram (ECG), cardiac enzymes, oxidative stress markers, inflammatory genes expression, histopathological and immunohistochemical changes were assessed. Administration of AZ and Capta alone or in combination cause cardiotoxicity. This was indicated by elevated LDH and CTNI levels, ECG changes as increased HR, prolonged QT interval and elevated ST segment accompanied by cardiac histopathological changes. There was a significant reduction in antioxidants SOD, GSH, TAC, and catalase, alongside a significant rise in oxidative stress MDA and NO. Significant rise of ERK, TNF-α, NF-ҡB, PI3K/AKT, Il-1β and IL-6, in both the Capta20 and AZ+Capta groups in dose dependent manner. The Coadministration of AZ and Capta20 produced intense immunoexpression of caspase-3 and BAX and wide areas of negative reactivity for Bcl-2. Coadministration of AZ and Capta induced cardiotoxicity through oxidative stress, inflammation, and apoptosis pathways. It is important to educate healthcare providers and patients about the potential harmful interactions.

Quantitative in vitro-to-in vivo extrapolation of human adrenergic and trace amine-associated receptor 1 potencies of pre-workout supplement ingredients using physiologically based kinetic modelling-based reverse dosimetry

The present study predicts effective doses of a set of phenethylamine (PEA) analogues that are frequently present in pre-workout and weight-loss food supplements, to prioritize these compounds for further risk assessment. In vitro determined EC50 values of PEA analogues for multiple human adrenergic receptor (ADR) subtypes (ADRα1A, α1B, α1D, α2A, β1, β2) and trace-amine associated receptor 1 (TAAR1) were extrapolated to human ED50 values by using physiologically based kinetic (PBK) modelling-based reverse dosimetry combined with in silico and in vitro determined PBK model input parameters. The predicted ED50 values of the studied PEAs for activation of ADRα1A/B/D, ADRα2A, ADRβ1 and TAAR1 were within a range of 0.914-29.7 mg/kg body weight (bw), 139-234 mg/kg bw, 0.0839-38.8 mg/kg bw and 0.995-264 mg/kg bw, respectively. Comparison of the predicted ED50 values with reported intake values revealed that particularly the exposure of the PEA analogues higenamine, isopropyloctopamine, β-methylphenethylamine and p-synephrine is in the same range or exceeds the predicted ED50 values. This suggests that these PEAs can (in)directly affect the cardiovascular system after the intake of food supplements. These PEA analogues should therefore be considered as high priority compounds for further risk assessment. In conclusion, our study shows that the use of quantitative in vitro-to-in vivo extrapolation (QIVIVE) of adrenergic and TAAR1 potencies using a generic PBK model can serve as an efficient prioritization method for a whole set of chemical analogues.

Isolation and Characterization of β-Phenylethylamine-Producing Lactic Acid Bacteria from Dairy Products

β-phenylethylamine (PEA) is a neuroactive trace amine synthesized by the enzymatic decarboxylation of phenylalanine. PEA is involved in the improvement of mood and attention. Functional foods enriched in this compound could, therefore, be of interest to the food industry. PEA is produced by microbial activity in certain foods, but usually only in small amounts. The search for PEA-producing microorganisms with good technological properties is thus a pre-requisite if such functional foods are to be produced. This work reports the isolation of thirty-three PEA-producing bacterial strains from samples of different dairy products. They belong to the genus Enterococcus, and the species Levilactobacillus brevis. Identified strains of Enterococcus durans were then selected for technological characterization. Some of them showed properties of interest. In this species, PEA was determined to be produced via the action of tyrosine decarboxylase, encoded by the gene tdcA. This implies that, apart from PEA, a concomitant production of tyramine, a toxic biogenic amine, was observed.