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Occurrence of biogenic amines in fresh fish and fishery products constitute a significant safety concern. Ingestion of histamine is identified as the causative agent of several food poisoning incidences on an annual basis. In addition, cadaverine, putrescine and tyramine have been recognized as potentiators of histamine poisoning. Accumulation of biogenic amines in fresh fish and fishery products has been mainly attributed to growth of bacteria possessing amino acid decarboxylase activity, which is facilitated by lack of hygienic conditions and strict temperature control during their storage. To this end, the effectiveness of traditional and modern approaches to control biogenic amine accumulation has been in the epicenter of intensive study. The aim of the present review article is to update and integrate current knowledge regarding the biogenic amine content of fresh fish and fishery products as well as the capacity of traditional and emerging control strategies.

Octopamine and Tyramine are biogenic amines that have been demonstrated to play an important immunological role in white shrimp, Litopenaeus vannamei. G protein-coupled receptors, known as seven-transmembrane domain receptors, are a variety of neurotransmitter receptors which are sensitive to biogenic amines for initiating the cell signaling pathway. In present study, we cloned and characterized an octopamine/tyramine receptor (LvOA/TA-R) from the hemocytes of L. vannamei, with a 1194 b.p. open reading frame that encodes 398 amino acids. Several bioinformatics analyses indicated that LvOA/TA-R had seven conserved hydrophobic transmembrane domains. The phylogenetic analysis and multiple sequence alignment indicated that LvOA/TA-R was orthologous to the OA/TA receptor of tiger shrimp, P. monodon. LvOA/TA-R was expressed in hemocytes and nervous tissue including circumoesphageal connective tissue and the thoracic and abdominal ganglia. Significant increases in LvOA/TA-R occurred in hemocytes of L. vannamei under Vibrio alginolyticus infection within 30-60 min of infection. Here, we demonstrated that LvOA/TA-R expression is upregulated in response to Vibrio alginolyticus infection and appears to be functionally responsible for the observed immune response. These results suggest that LvOA/TA-R mediates regulation of immunity, which promotes the resistance of L. vannamei to V. alginolyticus.

The innate cartilage extracellular matrix is avascular and plays a vital role in innate chondrocytes. Recapping the crucial components of the extracellular matrix in engineered organs via polymeric gels and bioinspired approaches is promising for improving the regenerative aptitude of encapsulated cartilage/chondrocytes. Conventional gel formation techniques for polymeric materials rely on employing oxidative crosslinking, which is constrained in this avascular environment. Further, poor mechanical properties limit the practical applications of polymeric gels and reduce their therapeutic efficacy. Herein, the purpose of this study was to develop a bioadhesive gel possessing dual crosslinking for engineering cartilage. Tyramine (TYR) was first chemically conjugated to the alginate (ALG) backbone to form an ALG-TYR precursor, followed by the addition of calcium peroxide (CaO

Hypothesis Due to the intrinsic nature of the surface-enhanced Raman scattering (SERS), the detection of molecules with weak binding affinities toward metal substrates is critical for development of a universal SERS sensing platform. We hypothesized the physical trapping of small pesticide molecules for active hot spot generation using tyramine-mediated crosslinking chemistry and silver nanoparticles (Ag NPs) enhances SERS detection sensitivity. Experiments Tyramine-mediated crosslinking chemistry for sensor application was validated by ultraviolet–visible absorption spectroscopy, scanning electron microscopy, dynamic light scattering, and Raman spectroscopy. SERS sensing platform using tyramine-mediated crosslinking reaction was systematically studied for detection of 1,4-dyethylnylbenzene as a model analyte. This sensor system was applied to detect two other pesticides, thiabendazole and 1,2,3,5-tetrachlorobenzene, which have different binding affinities toward metal surfaces. Findings The SERS signal of 1,4-dyethylnylbenzene obtained using this sensor system was 3.6 times stronger than that obtained using the Ag colloidal due to the nanogap of approximately 1.3 nm within the generated hot spots. This sensor system based on tyramine-mediated crosslinked Ag NPs was evaluated as a promising tool to achieve a solution based sensitive detection of various pesticide molecules that cannot be adsorbed on the surfaces of typical SERS substrates such as metal nanoparticles.

Tyramine beta-hydroxylase (TBH) is needed for the biosynthesis of the octopamine (OA) from tyramine (TA). Both OA and TA act as neurotransmitters, neurohormones, and neuromodulators in the invertebrate nervous system. In this study, TBH was identified in white shrimp, Litopenaeus vannamei, and further investigation on its potential function was conducted after inducing hypothermal stress and Vibrio alginolyticus infection. TBH of L. vannamei (LvTBH) was comprised 2178 nucleotide residues and contained an open reading frame encoding 408 amino acids, belonging to the Copper type II, ascorbate-dependent monooxygenases, was characterized by two Cu2_monooxygen domains and five glycosylation sites. LvTBH expression was especially abundant in muscle, and mainly in brain and thoracic ganglia of nervous system, eyestalk tissues, epithelium, and stomach, as determined by quantitative real-time PCR. The effects of hypothermal stress showed significant increases in LvTBH at 15, 30 and 60 min in brain and at 30 min in haemocyte, accompanied by an increase in OA level in haemolymph from 15 to 60 min. Significant increases in LvTBH occurred at 15, 30 and 60 min in haemocyte and at 60 min in brain tissue, and was proportional to the OA level of haemolymph under Vibrio alginolyticus infection from 30 to 60 min. Here, we demonstrated that LvTBH is functionally responsible for biogenic amine synthesis, suggesting that the increased release of OA in haemolymph for potential modulation of physiological and immunological responses is the consequence of the upregulated LvTBH gene expression in L. vannamei exposed to hypothermal stress and Vibrio alginolyticus infection.

[Background and purpose]: Given the overlapping clinical manifestations and pathology, the differentiation between essential tremor (ET) and Parkinson's disease (PD) is difficult. Our aims were to examine the plasma metabolomics profiling and their association with motor and non-motor symptoms (NMS) in patients with PD, and to determine differences between de novo PD compared to moderate-advanced PD vs. controls and patients with ET., [Methods]: Plasma samples were collected from 137 subjects including 35 age matched controls, 29 NOVO-PD, 35 PD and 38 ET patients. PD severity, motor and NMS including cognitive function were assessed using the UPDRS, NMS and PD cognitive rating scales, respectively. Metabolomics analysis was performed by UPLC-ESI-QToF-MS followed by unsupervised multivariate statistics. The area under the curve of the biomarkers according to distribution of their concentrations and the diagnosis of PD (NOVO-PD, advanced PD) vs ET and healthy controls was used as a measurement of diagnostic ability., [Results]: Several acyl-carnitines, bilirubin, tyramine and tetrahydro-21-deoxycortisol (THS) presented good predictive accuracy (AUC higher than 0.8) for differentiating de novo PD and advanced PD from controls and ET, suggesting an alteration in the lipid oxidation pathway. In multivariate regression analysis, metabolite levels were not significantly associated with motor and NMS severity in PD., [Conclusions]: Diverse acyl-carnitines, bilirubin, tyramine and some adrenal gland derived metabolites are suggested as potential biomarkers able to distinguish between PD from controls and ET., This work was supported by Junta de Castilla y León (BIO/BU06/14).

Mucuna pruriens (L.) DC var. pruriens is the natural source for L-DOPA, precursor of the neurotransmitter dopamine, used widely in the treatment of Parkinson's disease. However, L-DOPA synthesis in plants is mediated either by Catecholamine (CA) pathway or alternate pathway catalyzed by Cytochrome P450 (CYP450) class of enzymes. Interestingly, the CA pathway itself can be initiated either by tyrosine hydroxylase (TH) or polyphenol oxidase (PPO). The CA pathway mediated synthesis of L-DOPA has not yet been proved in M. pruriens albeit strong indications. Therefore, the present investigation is focused on metabolite analysis of major intermediates of CA pathway up to the formation of dopamine and expression analysis of the selected genes, in different tissues and callus cultures. The four major intermediates, L-tyrosine, tyramine, L-DOPA and dopamine, were detected using NMR spectroscopy and quantified by HPLC in the callus cultures and in different tissues of the field plant, respectively. The various stages of leaf tissue were also analyzed for metabolite profiling. The relative amount of intermediates detected during the ontogeny of leaf indicates that PPO mediated conversion of L-tyrosine to dopamine through L-DOPA is relatively higher compared to dopamine production from tyramine. Among the two possible enzymes, activity of PPO was 6.5-fold more than TH in metabolically active young leaves compared to intermediate leaves. The gene expression profiles comprising upstream genes of L-tyrosine synthesis and downstream up to dopamine synthesis shows strong correlation with L-DOPA synthesis. The study validates CA pathway mediated synthesis of L-DOPA with PPO as candidate enzyme, in M. pruriens.

Two new cadinane sesquiterpenes, cadinoschanes A and B (1 and 2), one new norlignan, lignanoschane A (6) along with seven known compounds, hibiscone B (3), 7β-O-β-glucopyranosyl bombaxone (4), 2,7β,8β-trihydroxy trans-calamenene 7-O-β-D-glucopyranoside (5), clemastanin A (7), (−)-3,4,3′,4′-tetrahydroxy-9,7′β-epoxylignano-7β,9′-lactone (8), N-trans-feruloyl tyramine (9), and methyl (3R)-3-[(3R)-3-{(3R)-3-hydroxybutanoyloxy} butanoyloxy} butanoate (10) were isolated from Abelmoschus moschatus subsp. tuberosus (Span.) Borss. Waalk. Their structures were determined on the basis of extensive spectroscopic methods, including 1D, 2D NMR and MS data and comparing experimental CD with theoretical CD calculations. Compounds 3 and 9 showed significant α-glucosidase inhibitory activity with IC50 values of 121.7 ± 3.9 and 4.3 ± 0.5 μg/mL, respectively, compared to those of a positive control, acarbose with IC50 value of 183.5 ± 12.2 μg/mL.

Hyaluronic acid (HA) is widely used as a filler owing to its excellent biocompatibility and biodegradability. However, commercial HA-based filler products have some limitations and can cause side effects due to the presence of residual chemical crosslinking agents. In this study, tyramine (Tyr) was introduced into HA to impart photocrosslinking ability to HA, and a photocrosslinked hydrogel was formed using a less toxic vitamin B2 derivative as a photoinitiator. For injection, an injectable filler was prepared by converting the photocrosslinked hydrogel to a microgel form. The crosslinking of the tyramine-modified HA (HA-Tyr) hydrogel, which can be applied as a soft tissue filler, increased with an increase in the irradiation time, and the crosslinked hydrogel showed excellent mechanical strength, elastic recovery rate, and injectability. It also showed non-cytotoxicity and cell proliferation behavior in fibroblasts. Therefore, injectable HA hydrogels have great potential as an alternative to conventional commercial dermal fillers.

Silk fibroin (SF) is a promising biomaterial with attractive properties, however, the practical applications of pure regenerated SF materials were severely restricted by their poor water retention and low elasticity. In this study, a tyramine-modified hyaluronic acid (mHA) was introduced to SF chains, followed by constructing double-network hydrogels via laccase-mediated crosslinking of SF and mHA. Mechanism of the enzymatic coupling reaction between SF and mHA was investigated using the model compounds. The morphology, mechanical property, and swelling behavior of SF-g-mHA hydrogel were evaluated. The results reveal that combination use of SF and mHA endowed the obtained hydrogels with high structural stability, improved mechanical properties and drug release behavior, which overcame the intrinsically poor formability of the pure fibroin hydrogels. This work provides a novel method to construct a double-network hydrogel with high flexibility and toughness, and expands the application range of the SF-based materials in biomedical fields.

We have developed an upconversion nanoparticles (UCNPs) based fluorescence immunoassay for simultaneously detecting tyramine and histamine in foods. The anti-tyramine and anti-histamine antibody were linked to NaYF4Yb, Tm (emission at 483 nm) and NaYF4Yb, Er (emission at 550 nm) UCNPs as multicolor signal probe, respectively. The tyramine and histamine coating antigen were connected to magnetic microspheres as capture probe, respectively. Base on a competitive format, capture probes compete with analytes to combine corresponding signal probes. Under excitation at 980 nm, the formed competitive immune-complex fluorescent signal at 483 and 550 nm indicates concentration of tyramine and histamine, respectively. This immunoassay has detection linear from 0.5 to 100 μg L−1 with limit of detection (LOD) of 0.1 μg L−1 for tyramine, and 0.1–100 μg L−1 with LOD of 0.01 μg L−1 for histamine, respectively. This multiplexed analysis format has potential applications for rapid, efficient detecting multiple food risk factors.

Tacinga inamoena is a cactus na``tive to the Northeast region of Brazil, used in popular medicine to treat disorders of the urethra as well as asthma and inflammation. Of the roots from T. inamoena, five previously unreleased compounds in the genus, β-sitosterol-3-O- d -glucopyranoside, N-trans-feruloyl-4-O-methyldopamine, N-cis-feruloyl-4-O-methyldopamine, N-trans-feruloyl tyramine and N-cis-feruloyl tyramine were isolated and their structures were elucidated by spectroscopic analysis (IR, MS and NMR). The antimicrobial activities of the partitioned phases were evaluated against bacterial and fungal strains, with promising results, especially of the ethyl acetate phase against Staphylococcus aureus ATCC 25,923. Furthermore, in the modulation tests between the phases and β-sitosterol-3-O- d -glucopyranoside with aminoglycosides, cephalosporins and quinolones, against the strains of E. coli 5A and Pseudomonas aeruginosa, there was a substantial increase of the activity of these antibiotics, with a significant decrease of MICs. The products from T. inamoena showed low toxicity in human erythrocytes. The present study presented relevant compounds and important antibacterial activities and suggests that the glycosylated β-sitosterol can be used to modulate the activity of antibiotics.

In this study, an efficient enzymatic process for the synthesis of 4-hydroxyphenylacetaldehyde (4-HPAA) from tyramine was developed using whole cells of recombinant Escherichia coli co-expressing primary amine oxidase (PrAO) from E. coli and catalase (CAT) from Bacillus pumilus. The reaction conditions for the synthesis of 4-HPAA were systematically optimized starting from a monophasic aqueous buffer. The optimum reaction temperature, pH, and biocatalyst loading were 33 °C, 7.5, and 20 g/L wet cells, respectively. Substrate feeding strategies were employed to alleviate substrate inhibition, providing a 14.8 % increase in yield. A biphasic catalytic system was explored to avoid product inhibition and thus further improve the 4-HPAA yield. Ethyl acetate was found to be the best organic solvent, and the optimum volume ratio of the organic phase to the aqueous phase was 40 % (v/v). Under the optimized conditions on a 1 L scale, a yield of 76.5 % was obtained with a substrate concentration of 120 mM. Thus, the bioconversion was more efficient in the ethyl acetate/buffer biphasic system than in the monophasic aqueous system, and the yield of 4-HPAA was improved 1.89-fold.

Tyramine (TA), a biogenic monoamine, plays various important physiological roles including immunological regulation in invertebrates. In this study, the effects of TA on the regulation of immune resistance, carbohydrate metabolism and biogenic monoamine, as well as its signaling pathway in Macrobrachium rosenbergii were determined. Results showed that total haemocyte count, hyaline cells, semigranular cells, and phenoloxidase activity per 50 μL of haemolymph and per granulocyte (the sum of semigranular and granular cells) at 0.5 h as well as phagocytic activity and clearance efficiency to Lactococcus garvieae at 1 h of prawn injected with TA at 1 nmol prawn−1 significantly increased, but the significantly decreased plasma lysozyme activity, phagocytic activity, clearance efficiency, and haemolymph glucose and dopamine were observed in prawn injected with TA at 10 nmol prawn−1 for 0.5 h. Respiratory bursts and haemolymph lactate in two TA-injection treatments at 0.5 h and 0.5–1 h, respectively, were significantly higher than those of the saline control, and in addition, TA depressed dopamine release in a dose-dependent manner after 0.5 h of TA injection. All the examined parameters returned to control levels after prawn injected with TA for 2 h. The inhibited effect of TA (at 10 nmol prawn−1 injection) on the phagocytic activity and clearance efficiency to pathogens was blocked by prazosin (an α1 adrenoceptors antagonist). For prawn received TA for 1 h then challenged with Lactococcus garvieae at 2 × 105 colony-forming units prawn−1, the survival ratio of TA 1 nmol prawn−1-injected prawn significantly increased by 20%, compared to the saline-challenged control or TA 10 nmol prawn−1-injected prawn after 144 h of challenge. These results suggested that the level of dopamine release suppression regulated by TA resulted in the immunoenhancing or immunosuppressive effects in prawn, and the signaling pathways of TA in mediating immune function were through octopamine (OA)/TA receptors.

The influence of under-fermented (UF) cocoa (0 to 65 %) on bioactive amines in chocolate and their in vitro bioaccessibility was investigated. The same amines were found in all treatments; however, treatments were divided into two groups regarding total amines [020 % UF (34 mg/kg) and 35 to 65 % UF (17 mg/kg)] and phenolic levels [lower and higher, respectively]. Serotonin, tyramine, putrescine, cadaverine, agmatine and phenylethylamine were higher in chocolate with ≤ 20 % UF cocoa. Histamine and spermidine were not affected. Digestibility studies indicated that low levels of amines were present in the oral phase. Gastric digestion was effective in releasing tyramine, spermidine and phenylethylamine from conjugates. Serotonin and agmatine were not detected after in vitro digestion of chocolate with ≥ 35 % UF cocoa. Histamine was released during in vitro intestinal digestion. By adding different proportions of UF cocoa during chocolate production, the levels and bioaccessibility of amines can be modulated.

Interpreting sensory information requires its integration with the current behavior of the animal. However, how motor-related circuits influence sensory information processing is incompletely understood. Here, we report that current locomotor state directly modulates the activity of BAG CO

Marinades are increasingly used to manufacture raw fish products. In corresponding meats, marinating is known to have a major effect on the composition of the microbiome, but the effect of marinating on fish is not known as well. This knowledge gap prompted our study of the microbial ecology and amine formation in marinated and unmarinated modified atmosphere commercially packaged rainbow trout fillet strips. According to our findings, marination increased the maximum concentrations (7-8 log CFU/g) of psychrotrophic bacteria by one loga-rithmic unit and led to 5 times higher average tyramine concentrations than the corresponding unmarinated product. Instead, trimethylamine concentrations were 30 times higher in the unmarinated product than those in the marinated one. According to the 16 S rRNA sequence analyses, lactic acid bacteria (LAB) predominated in the marinated strips one day after the use-by date, whereas in the unmarinated strips Fusobacteriaceae and LAB were the dominating taxa. Based on the culture-dependent analysis, Latilactobacillus fuchuensis was the prevailing LAB in both products. Since the subset of L. fuchuensis strains tested was able to produce tyramine in vitro, we hypothesise that the use of the acidic marinade activated the production of tyrosine-decarboxylating enzymes in L. fuchuensis and led to the increased tyramine concentrations.

Cyanobacterial harmful algal blooms (cyanoHABs) are a global problem with serious consequences for public health and many sectors of the economy. The use of algicidal bacteria as natural antagonists to control bloom-forming cyanobacteria is a topic of growing interest. However, there are still unresolved questions that need to be addressed to better understand their mode of action and to implement effective mitigation strategies. In this study, thirteen bacterial strains isolated from both scums and concentrated bloom samples exhibited algicidal activity on three Microcystis aeruginosa strains with different characteristics: the axenic microcystin (MC)-producing strain M. aeruginosa PCC7820 (MaPCC7820), and two environmental (non-axenic) M. aeruginosa strains isolated from two different water bodies in Poland, one MC-producer (MaSU) and another non-MC-producer (MaPN). The bacterial strain SU7S0818 exerted the highest average algicidal effect on the three cyanobacterial strains. This strain was identified as Morganella morganii (99.51% similarity) by the 16S rRNA gene analyses; hence, this is the first study that demonstrates the algicidal properties of these ubiquitous bacteria. Microscopic cell counting and qPCR analyses showed that M. morganii SU7S0818 removed 91%, 96%, and 98.5% of MaPCC7820, MaSU and MaPN cells after 6 days of co-culture, respectively. Interestingly, the ultra-high-performance liquid chromatography-tandem mass spectrometer (UHPLC-MS/MS) analyses showed that this bacterium was involved on the release of several substances with algicidal potential. It was remarkable how the profile of some compounds evolved over time, as in the case of cadaverine, tyramine, cyclo[Pro-Gly] and cyclo[Pro-Val]. These dynamic changes could be attributed to the action of M. morganii SU7S0818 and the presence of associated bacteria with environmental cyanobacterial strains. Therefore, this study sheds light on how algicidal bacteria may adapt their action on cyanobacterial cells by releasing a combination of compounds, which is a crucial insight to exploit them as effective biological tools in the control of cyanoHABs.

High boron (B) levels in oil and gas produced waters prevent its beneficial reuse as irrigation water without proper treatment. Aluminum (Al) electrocoagulation (EC) is a promising technology for B removal, but further research and development is needed to optimize EC for use in removing B from produced waters. To this end, B removal by adsorption onto insoluble aluminum hydroxide solids, generated by EC in simulated brines (up to 50,000 mg/L NaCl) and real oilfield produced waters, was studied. B removal during EC was greater than when aluminum hydroxide solids formed by EC were subsequently exposed to B containing solutions. Working parameters affecting B removal during the EC process, including current, total dissolved solid (TDS), temperature, pH, scale-forming cations and organic matter, were investigated to explore ways to achieve higher B removal. Boron removal increased with increased current loading and time, and with the concomitant increased Al solids concentration. However, too high a current loading limited B removal because of a change in the structure of the aluminum hydroxide solids. Higher TDS decreased B removal slightly, but lower TDS concentrations limited the use of higher current loadings. Temperature increased during EC treatment, particularly at higher current loadings, and this inhibited B removal due to an accelerated aggregation of amorphous Al solids into larger, denser, and presumably more crystalline particles. The best B removal occurred at pH 8, corresponding to a slightly positive zeta potential for aluminum hydroxide and a small but significant fraction of negatively charged B species. Scale-forming cations such as Ba

Biogenic amines (BA) are often present at high concentrations in fermented meat and cause foodborne illness. The aim of this work was to screen amine-degrading starters for Roucha (a fermented meat) to improve product safety and quality. Firstly, Weissella viridescens F2 and Lactiplantibacillus plantarum His6 with multi-copper oxidase activity and high degradation rates towards histamine and tyramine were selected as single or mixed starters. Additionally, the effect of starters on bacterial community succession, acid production, BA accumulation, free amino acid profiles, and volatile compound profiles were evaluated during the fermentation of Roucha. Results indicated that all starters could effectively reduce the accumulation of BA in Roucha. At the end of fermentation, Lpb. plantarum His6 as a single starter reduced the histamine level (38.15 %), while mixed starters (Lpb. plantarum His6 + W. viridescens F2) possessed a high tyramine-reduction rate (54.95 %) and total BA-reduction rate (46.64 %). Bacterial succession analysis revealed that starters could help establish the dominance of lactobacilli or Weissella quickly, which contributed to the direct degradation of BA and inhibited the growth of amine-producing bacteria. Furthermore, Lpb. plantarum His6 could promote the accumulation of essential amino acids (leucine, phenylalanine, threonine, isoleucine), sweet and umami amino acids (glycine, threonine, glutamate), and volatile compounds of good odor, indicating that this strain greatly contributed to the development of good taste and aroma characteristics in Roucha. Overall, this work shows that the application of amine-degrading starters is an effective strategy to reduce the BA accumulation and improve the quality of Roucha. Thus, these findings can provide foundations for the industrial production of Roucha.

The chemical characterization of the 70% hydromethanolic extract of Atriplex semibaccata (family: Chenopodiaceae) afforded a new methoxylated flavonol triglycoside, atrisemibaccatoside A (1), and a new lignanamide, (N-[(E)-m-hydroxycinnamoyl]tyramine (7), as well as, five known flavonols (2–6) and two lignanamides (8–9). The structures of the isolated compounds were established depending upon LR&HR-FAB-MS, 1D and 2D NMR spectroscopic analyses. The cytotoxic activity of the isolated compounds (1–4, and 7–9) was investigated. Compounds 7, 8 and 9 weakly inhibited the proliferation of leukemia CCRF-CEM cells with IC50 values of 78.5, 46.3, and 71.2 μg/ml, respectively, and exhibited no cytotoxicity against Hela and HSC-2 cancer cells. A chemosystematic significance study was evaluated depending upon the chemical constituents of A. semibaccata comparing with those of other Atriplex species.

Monoamine neuromodulators such as dopamine (DA), norepinephrine (NE), serotonin (5-HT), octopamine, and tyramine are signaling molecules in the nervous system, where they play critical roles in both health and disease. Given the complex spatio-temporal dynamics, similar structural features, and different receptors, studying their dynamics has been limited using conventional methods such as microdialysis and electrochemistry. However, recent advances in optics have facilitated the development of imaging-based detection methods. In this review, we summarize current detecting approaches for specific monoamines, emphasizing their design strategies, detection properties, applications, and limitations. We highlight the genetically encoded GPCR-based sensors for DA and NE, which have a high signal-to-noise ratio and selectivity, and can be used in vivo in different species. Finally, we discuss the potential for using this approach to generate new neuromodulator sensors with non-overlapping spectra, which will ultimately pave the way for studying the interplay between various neuromodulators and neurotransmitters.

Tyramine (TA), a neuroactive chemical, plays various important physiological roles in insects by activating distinct G-protein-coupled receptors (GPCRs). In this study, we investigated the effects of by pharmacological injection of TA on immune resistance regulation and its signal pathway in white shrimp Litopenaeus vannamei. Results showed significant increases in the total haemocyte count (THC), semigranular cells (SGCs), granular cells (GCs), phenoloxidase (PO) activity per 50 μL of haemolymph and respiratory bursts (RBs) at 0.5, 1, 2 and/or 4 h; hyaline cells (HCs) at 0.5 h, as well as phagocytic activity (PA) and clearance efficiency (CE) at 2, 4 and/or 8 h, but significantly decreased PO activity per granulocyte at 0.5–2 h for shrimp injected with TA at 100 and 1000 pmol shrimp−1. Plasma lysozyme activities of TA-injected shrimp were significantly higher than those of the saline control at 1 h. All of the immune parameters had returned to control levels by 8 h after receiving TA except the clearance efficiency, which had returned to its control value by 16 h. The TA injection also significantly decreased the mortality of shrimp challenged with Vibrio alginolyticus. Furthermore, immune parameters of shrimp that received TA at 1000 pmol shrimp−1 for 1 h were higher than those of shrimp that received the saline. The upregulating effect of TA was blocked by co-injection with phentolamine (Phe) in terms of the THC, HC, SGCs, PO activity, PA and CE; by co-injection with prazosin (Pra) in terms of the THC, HC, SGCs, PO activity, PA and CE; by co-injection with propranolol (Prop) in terms of the PA and CE; and by co-injection with metoprolol (Meto) in terms of the THC and SGCs. The most potent effect in immunocompetence of tested antagonists was Pra, and except for circulating haemocyte, it was Phe. These results suggest that ≤1000 pmol shrimp−1 of a TA injection mediates transient upregulation of immunity, which in turn promotes the resistance of L. vannamei to V. alginolyticus, and the active effects are mediated via octopamine/tyramine (OA/TA) receptors.

Mental disorders have a multifactorial etiology and stress presents as one of the causal factors. In depression, it is suggested that high cortisol concentration contributes directly to the pathology of this disease. Based on that, the study aims to evaluate the potential antidepressant effect of Riparin IV (Rip IV) in mice submitted to chronic stress model by repeated corticosterone administration. Female Swiss mice were selected into four groups: control (Ctrl), corticosterone (Cort), Riparin IV (Cort + Rip IV) and fluvoxamine (Cort + Flu). Three groups were administrated subcutaneously (SC) with corticosterone (20 mg/kg) during twenty-one days, while the control group received only vehicle. After the fourteenth day, groups were administrated tested drugs: Riparin IV, fluvoxamine or distilled water, by gavage, 1 h after subcutaneous injections. After the final treatment, animals were exposed to behavioral models such as forced swimming test (FST), tail suspension test (TST), open field test (OFT), elevated plus maze (EPM) and sucrose preference test (SPT). The hippocampus was also removed for the determination of BDNF levels. Corticosterone treatment altered all parameters in behavioral tests, leading to a depressive- and anxious-like behavior. Riparin IV and fluvoxamine exhibit antidepressant effect in FST, TST and SPT. In EPM and OFT, treatment displayed anxiolytic effect without alteration of locomotor activity. Corticosterone administration decreased BDNF levels and Riparin IV could reestablish them, indicating that its antidepressant effect may be related to ability to ameliorate hippocampal neurogenesis. These findings suggest that Riparin IV improves the depressive and anxious symptoms after chronic stress and could be a new alternative treatment for patients with depression.

A traditional Thai fermented pork, nham, is a product popularly consumed in Thailand. Fermentation of the protein-rich product by uncontrolled bacterial community can result in high amounts of hazardous biogenic amines (BA). This study aimed to unveil dynamics of microbial community and its relation to BA accumulation in nham. Three batches of nham were analyzed for pH, lactic acid bacteria population, concentrations of organic acids and BA. Bacterial communities were analyzed by pyrosequencing of 16S rRNA gene amplicons. In all batches, pH dropped to the quality standard of nham (≤4.6) within 3–5 days by production of lactic acid and acetic acid. Initial BA levels varied batch-by-batch and increased with fermentation time. In the highest quality batch, levels of histamine, tyramine, and total BA were within the recommended safety limits (200, 100 and 1000 mg/kg, respectively) throughout the 10-days study. However, in other batches, unsafe levels of tyramine and total BA were found after 5 days of fermentation. The results indicated that over-fermentation and inferior conditions of ingredients increased risk due to high levels of BA. Lactobacillus, Lactococcus, Pediococcus and Weissella were prevalent and comprised >90% of total bacteria during fermentation. Weissella was predominant in the batch with low BA while Lactobacillus and Pediococcus were predominant in the higher BA batches. A negative correlation between Weissella dominance and total BA was observed (r = −0.90, p = .003). A 10% increase in dominance of Weissella was associated with 75–170 mg/kg decrease in total BA. W. hellenica was the species prevalent only in low BA batch. Therefore, W. hellenica isolates were suggested as subjects for future study to develop efficient starter culture securing safety of nham.

A selective, simple and environment-friendly type fluorescence sensing platform between upconversion nanoparticles (UCNPs) and melanin-like polymer utilizing the photoinduced electron-transfer (PET) mechanism was developed. The effective fluorescence quenching of UCNPs by melanin-like polymers could detect tyramine and tyrosinase (TYR) activity through the bio-catalysed oxidation of tyramine to the melanin-like polymer products. At optimal conditions, the range of linearity in detection was 0.167–33.3 μΜ for tyramine, and the limit of detection of tyramine was 0.026 μΜ. The linear range of TYR was 0.0033–1 U·mL−1, and the limit of detection of TYR was 0.003 U·mL−1. Furthermore, the strategy could be applied to real sample analysis with satisfactory results.

Tyramine and histamine are considered the most toxic biogenic amines (BAs) and are often found in high concentrations in fermented foods, such as cheese, and beverages. Their control is critical to assure food safety. Recently the use of food borne BAs degrading bacteria has been proposed. The aim of this study was to isolate bacteria from Incanestrato di Castel del Monte, a raw ewe's cheese, unable to produce histamine and tyramine and, at the same time, able to degrade them. Twenty-four strains with different BAs-producing and degrading abilities were isolated. Twelve strains produced tyramine, while none of them histamine in agreement with molecular data which showed the absence in these strains of hdc gene. Only 2 strains did not degrade tyramine, while the others showed a degradation % ranging from 3.83 ± 0.15 to 62.45 ± 3.98. Tyramine degradation % varied from 6.23 ± 012 to 70.74 ± 2.15. The most interesting strains appeared to be A422 (L. casei), and A143 (E. casseliflavus), since they show a quite high % of degradation of both BAs, and did not show decarboxylase activity. Selected bacteria could be used as starter culture to reduce tyramine and histamine concentration in raw milk cheeses.

The phenethylamine alkaloid hordenine, present in germinated barley, was identified recently as a functionally selective dopamine D2 receptor agonist contributing potentially to the rewarding effects of drinking beer. Here, it was shown that the hordenine precursor N-methyltyramine binds with a similar affinity to the dopamine D2 receptor as hordenine (Ki 31.3 µM) showing also selectivity towards the G protein-mediated pathway over the β-arrestin pathway. Using a newly developed UHPLC–ESI–MS/MS method to monitor beer production, we demonstrated that hordenine and N-methyltyramine were released continuously from barley malt during mashing and were stable during fermentation and conditioning. The amounts released from different base malt types were in a similar range but tended to be higher from caramel malts. Hordenine and N-methyltyramine concentrations in 24 types of beer varied between 1.05–6.32 and 0.59–4.61 mg/L, respectively. Thus, the human uptake of the alkaloids during beer consumption is in the low milligram range.

Fossa cheese is a typical Italian cheese characterised by ripening in pits dug in tuffaceous rock. In this work, 1H NMR spectroscopy was applied to characterise the lipid fraction and the metabolite profile of Fossa cheese produced with sheep's milk. Samples were collected before and after ripening in different pit environments. The higher levels of free amino acids (FAAs) found in samples suggest that cheeses underwent a strong proteolytic process. Differences in quantity and variety of FAAs were influenced by the two ripening environments. Diacylglycerols and butyric acid, which can be linked to lipolysis, were detected in all the samples. Longer ripened samples had higher contents of rumenic acid (18:2 cis-9, trans-11) and glycerol, and lower contents of lactate and citrate. The presence of tyramine was observed by two-dimensional NMR, while cadaverine was not detected in the samples.

Lactobacilli have a long history of safe use in human nutrition, however, inclusion of any new strain, despite its safe usage evidence, warrants proper analysis of its safety and toxicity under the purview of existing regulations. In the present investigation, Lactobacillus plantarum MTCC 5690 and Lactobacillus fermentum MTCC 5689 were evaluated for their safety and toxicity using both in vitro and in vivo approaches. The in vitro assays included mucin degradation, hemolytic activity, biogenic amine production and platelet aggregation assay. The safety was also assessed using acute, subacute and subchronic assays, bacterial translocation studies, intravenous and intravenous administration and genotoxicity assay in murine model. The outcome of this toxicological safety assessment indicated that both the test strains lacked any harmful metabolic activity or any genotoxic effects. Furthermore, the results of oral toxicity studies in mice revealed that short term administration of high cell mass concentration of 1012 cfu/animal as well as long term feeding of the probiotic strains did not alter any hematological, general health parameters or cause any organ specific disorder. Based upon these scientific assessments and supported by long history of safe use, both MTCC 5690 and MTCC 5689 may be considered safe for human consumption.

Shuidouchi is a traditional Chinese fermented soybean product and its quality is largely affected by the microbes involved in the fermentation. In this study, eleven Shuidouchi samples were collected from southwest China and the microbial diversity and its correlations with chemical characteristics were investigated. Bacterial community was detected using 16S rRNA sequencing, along with bacterial and fungal viable plate counts. Biogenic amines and other chemical characteristics were determined by HPLC and corresponding chemical reaction methods. Among eleven Shuidouchi samples, 21 phyla and 356 genera were identified. Firmicutes, Bacteroidetes and Proteobacteria were the predominant phyla while Bacillus, Bacteroides and Lactobacillus were the main genera. The average cell number of bacteria, lactic acid bacteria and fungi were 1.6 × 106, 5.9 × 104 and 7.6 × 103 CFU/g, respectively. HPLC results showed that the mean concentration of tryptamine, β-phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine and spermine were 23.11, 3.66, 12.21, 7.12, 8.13, 22.98, 24.72, and 39.00 mg/kg, respectively. The average content of other characteristics including amino acid nitrogen, titratable acidity, and reducing sugar were 2.08, 3.44, and 25.78 g/kg, respectively. Shuidouchi samples were slightly acidic or neutral. Fibrinolytic enzyme activity was detected only in one sample. Among top 52 identified genera, 9 genera showed positive correlations with the chemical characteristics of Shuidouchi while 15 genera were negatively associated. Our results indicated that Shuidouchi contained rich microbial resources and were edible safety based on the tested indexes. The associations identified between microbes and chemical characteristics could be further utilized in the food fermentation industry.

The concentrations of seven biogenic amines and twenty-three free amino acids and ammonium ion were monitored in different craft beers acquired in the Spanish market. Besides, a statistical approach was conducted using multivariate statistical analysis. The significant differences observed between manufacturing batches, both in the content of free amino acids and biogenic amines, reveal a lack of homogeneity in the production, probably caused by the craft brewing process. A great variability among samples was observed in terms of their content in free amino acids. The main biogenic amine was putrescine, followed by tyramine and histamine; however, the concentrations were below those considered as toxic in alcoholic beverages. Strong negative correlations (P

Mescaline is a psychedelic phenethylamine found in different species of cacti. Currently, mescaline's acute subjective effects and pharmacokinetics are investigated in several modern clinical studies. Therefore, we developed a bioanalytical method for the rapid quantification of mescaline and its metabolites in human plasma. Mescaline and its metabolites 3,4,5-trimethoxyphenylacetic acid (TMPAA), N-acetyl mescaline (NAM), and 3,5-dimethoxy-4-hydroxyphenethylamine (4-desmethyl mescaline) were simultaneously analyzed by ultra-high performance liquid chromatography tandem mass spectrometry (LC-MS/MS). Optimal chromatographic separation was achieved with an Acquity Premier HSS T3 C

Elucidating the mechanism for high metastasis capacity of triple negative breast cancers (TNBC) is crucial to improve treatment outcomes of TNBC. We have recently reported that nicotinamide N-methyltransferase (NNMT) is overexpressed in breast cancer, especially in TNBC, and predicts poor survival of patients undergoing chemotherapy. Here, we aimed to determine the function and mechanism of NNMT on metastasis of TNBC. Additionally, analysis of public datasets indicated that NNMT is involved in cholesterol metabolism. In vitro, NNMT overexpression promoted migration and invasion of TNBCs by reducing cholesterol levels in the cytoplasm and cell membrane. Mechanistically, NNMT activated MEK/ERK/c-Jun/ABCA1 pathway by repressing protein phosphatase 2A (PP2A) activity leading to cholesterol efflux and membrane fluidity enhancement, thereby promoting the epithelial-mesenchymal transition (EMT) of TNBCs. In vivo, the metastasis capacity of TNBCs was weakened by targeting NNMT. Collectively, our findings suggest a new molecular mechanism involving NNMT in metastasis and poor survival of TNBC mediated by PP2A and affecting cholesterol metabolism.

The aim of this study was to investigate the influence of organic solvents on the electrophoretic separation of phenylethylamines. The background electrolyte composition was adjusted with different protic (methanol, ethanol, and 2-propanol) and aprotic (dimethyl sulfoxide and acetonitrile) solvents. Two groups of analytes were studied. The first group contained phenylethylamines with an amine group only, DL-1-phenylethylamine and amphetamine. The second group represented phenylethylamines with both amine and phenolic hydroxyl groups, dopamine and tyramine. Experiments revealed no or minor influence of the organic modifiers on the electromigration behavior of the analytes from the first group (containing only the amine group) and a drastic effect on the second group (containing the additional phenolic hydroxyl group). Dopamine and tyramine showed various electrostatic, hydrophobic, and hydrogen-bonding interactions with both protic and aprotic organic solvents. The dependence of the electrophoretic mobility of dopamine and tyramine on the concentration of the organic solvents provided direct evidence of the formation of hydrogen bonds between dopamine or tyramine and the organic solvent. The baseline separation was achieved by the addition of at least 20% v/v of organic solvent (protic or aprotic) to the background electrolyte. The analyte migration time repeatabilities were within 0.7-4.1% for absolute and 0.2-1.9% for normalised migration times. The proposed bonding mechanism and behavior of phenylethylamines were examined and confirmed by NMR spectroscopy.

Monoamine oxidase B (MAO-B) inhibitors are established therapy for Parkinson's disease and act, in part, by blocking the MAO-catalysed metabolism of dopamine in the brain. Two propargylamine-containing MAO-B inhibitors, selegiline [(R)-deprenyl] and rasagiline, are currently used in the clinic for this purpose. These compounds are mechanism-based inactivators and, after oxidative activation, form covalent adducts with the FAD co-factor. An important consideration is that selegiline and rasagiline display specificity for MAO-B over the MAO-A isoform thus reducing the risk of tyramine-induced changes in blood-pressure. In the interest of discovering new propargylamine MAO inhibitors, the present study synthesises racemic N-propargylamine-2-aminotetralin (2-PAT), a compound that may be considered as both a six-membered ring analogue of rasagiline and a semi-rigid N-desmethyl ring-closed analogue of selegiline. The in vitro human MAO inhibition properties of this compound were measured and the results showed that 2-PAT is a 20-fold more potent inhibitor of MAO-A (IC

Parkinson's disease (PD) is a usual disease caused by degeneration of the central nervous system, which features the denaturation and death of dopaminergic neurons in the substantia nigra compact (SNc) of the midbrain. Neuroinflammation casts a consequential role in its pathogenesis, and the excessive activation of microglia as a major part of neuroinflammation cannot be ignored. Studies have indicated that Hordenine (HOR) functioned widely as an anti-oxidant and anti-inflammatory substance, but there are no reports on neuroinflammation effects. Therefore, this study is devoted to exploring the effect of HOR on neuroinflammation and its specific mechanism. In vivo, results revealed that HOR depressed the activation of microglia in SNc and protected dopaminergic neurons in the 6-hydroxydopamine (6-OHDA)-induced PD rat model, which terminally reduced movement disorders and weight loss. In vitro, studies have shown that HOR can inhibit inflammatory responses triggered by lipopolysaccharide (LPS) in BV-2 cells. More profound studies have discovered that the specific anti-inflammatory mechanism is intimately associated with the NF-κB and MAPK signaling pathways. All in it together, HOR acts as a significant role in preserving dopaminergic neurons by restraining neuroinflammation mediated by activation of microglia. This may provide a potential drug for Parkinson's treatment.

A signal-enhanced LFIA based on tyramine (TYR)-induced AuNPs aggregation has been developed for the sensitive detection of danofloxacin (DAN). In the model, the hydroxyl radical produced by HRP catalyzing H

Tilted disc syndrome (TDS) is considered a congenital anomaly due to a delayed closure of the embryonic fissure. It is characterized by an oblique orientation of the axis of the optic disc, associated with other posterior pole anomalies such as inferior crescent, situs inversus and inferior staphyloma. The aim of this review was to summarize the data supporting the current hypotheses for the pathogenesis of TDS, and its anatomical and functional clinical consequences. Recent imaging techniques, such as magnetic resonance imaging, wide-field fundus imaging, and 2- and 3-D optical coherence tomography have provided a new perspective on TDS and its complications. Different abnormalities have previously been reported, both in the anterior and posterior segments. The focus was on vision-threatening chorioretinal changes or complications, including choroidal neovascularization and serous retinal detachments and their therapeutic options. Based on clinical observations, assumptions were proposed to understand the occurrence of complications such as chorioretinal degenerative changes, choroidal neovascularization and polypoidal choroidal vasculopathy, macular serous retinal detachment, myopic foveoschisis and chorioretinal folds. These hypotheses could be referred to as the curvature "breaking point" hypothesis, the uneven growth "tractional" hypothesis, the "container-content" imbalance hypothesis, and the "choroidal funnel" hypothesis. Because these complications could also occur in other contexts, understanding the pathogenesis of TDS complications could help to understand their pathophysiology.

9 figures, 2 multimedia components.-- © 2021. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/, An enzymatic method for the direct (without pretreatment) minimally invasive tyramine determination in cheese is proposed. Colorimetric test strips containing tyramine oxidase (TAO), peroxidase and 3,3′,5,5′-tetramethylbenzidine (Q-TAO), allow tyramine determination through the RGB chromatic coordinates of the observed blue colour (LOD = 2.6·10−6 M, LOQ = 8.7·10−6 M, RSD% (n = 5; 1.8·10−4 M) = 3.2%). The strips are inserted in the sample for 2 min and then the RGB coordinates are measured using a smartphone. Previously, these Q-TAO strips have been also optimized for tyramine determination in cheese extract. To do that, a spectrophotometric method in solution for tyramine determination in cheese extracts has been developed, which included an in-depth study of the indicating reaction; this study has allowed to gain new information about the spectroscopic properties of different TMB species and, which it is more important, to detect cross-reactions between TAO and TMB species. A mathematical model has also been developed which relate the RGB signals obtained with the tyramine concentrations, the instrumental characteristics of the smartphone and the spectroscopic properties of the absorbing product of the enzymatic reaction., This work was supported by the MINECO of Spain (projects CTQ2016-76846R and PID2019-105408 GB-I00) and by Research groups funded by DGA-FEDER (group E25_17R, N&SB).

The aim of this study was to determine the biogenic amines (BAs) formed in chicken breast meat packaged using different techniques (AP, Hi-O2-MAP or VP) during the storage under different conditions (cold room or display case), to correlate the microbiological quality (TPC, LAB, Pseudomonas spp. and Enterobacteriaceae) of chicken meat with BAs formation and to assess the suitability of selected biogenic amines as indicators of chicken meat spoilage. The initial TPC of chicken fillets was 2.57–3.04 log cfu/g. Over time a systematic significant (p ≤ 0.05) increase in TPC was observed to >7.5 log cfu/g (AP and VP; display case) determined on day 9. It was found that cadaverine and tyramine dominated in quantitative terms in chicken fillets, regardless of packaging technique and storage conditions (166.00 mg/kg in AP meat in cold room on day 9 and 175.03 mg/kg on day 9 in MAP meat in display case, respectively). Taking into account the BAI, high and significant (p ≤ 0.05) correlation coefficients (from 0.51 to 0.95) were obtained with all analyzed indicators of microbiological quality. The concentration of cadaverine, putrescine contents or BAI can potentially serve as chemical quality indicator for freshness of chicken meat

Maslinic acid (MA), a pentacyclic triterpenoid obtained from olives that is characterized by its antiproliferative activity in tumor cells, has become a promising molecule that could be modified to improve cancer treatment. In this work we have synthesized in good yields several new MA conjugates, including glycerin, oligo(ethylene glycol), and amino acid derivatives (compounds 3a-f). The synthesis offers the possibility of recovering unreacted MA, and thus the scaling up of the process. For the tyramine-MA conjugate, compound 3f or TMA, the preparation has been optimized to a one-pot reaction. Solubility of conjugates in polar solvents has been measured, showing a marked increase of solubility with respect to MA. Moreover, we selected the tyramidyl maslinic acid conjugate (3f or TMA) to determine antitumor capacity over a wide range of cancer cell lines, including glioblastoma, melanoma, breast, lung, colorectal and pancreatic cancer. Our results clearly demonstrated that TMA induced higher cytotoxicity in all cancer cell types compared to MA. TMA was more effective than MA, especially in breast cancer cells (MCF-7) and melanoma cells (B16–F10) where IC50 reductions of 4.12 and 4.72, respectively, was detected. Interestingly, TMA showed a remarkable antitumor ability against the resistant HCT-15 colon cancer cell line. Furthermore, we demonstrated for the first time a relevant effect of a MA derivative against glioblastoma cells (A172 and SF-268). These results suggest that TMA is able to improve the antitumor characteristics of MA in a wide range of cancers and that it may be a promising compound for various tumor types, including resistant cancer.

Japanese radish Daikon (Raphanus sativus) sprouts were exposed, under the model plant growing conditions, to herbicide stress induced by triketone herbicides (mesotrione and sulcotrione) as well as degradation products (4-methylsulfonyl-2-nitrobenzoic acid, amino-4-(methylsulfonyl)benzoic acid, 2-chloro-4-mesylbenzoic acid and cyclohexane-1,3-dione). Changes in the content of selected l -tyrosine metabolites (dopamine, tyramine, normetanephrine) and catecholamine synthesis cofactors (water-soluble vitamins) were monitored in plant tissues using high-performance liquid chromatography. Normetanephrine content increased up to 0.13 mg per gram of sprouts, 1500-fold higher than in the control sample. Tyramine and dopamine content increased by 50 % and 100 %, respectively. These changes corresponded with changes in the content of B3 and B9 vitamins. It has been proved that contact of the plant with this group of herbicides and theirs degradation products leads to a disturbance in the l -tyrosine metabolism. Consequently, this also leads to significant changes in the quality of foods of plant origin.

This study presents electrochemical determination of tyramine (TA) using a new electrochemical sensor (TiO2-Ag/PPy/GCE) based on TiO2-Ag/PPy nanocomposite modified glassy carbon electrode (GCE). In addition to SEM, AFM and XRD analysis, the presented sensor was studied with respect to its response to Fe(CN)64−/3− and characterized by CV and EIS techniques. Under the optimum conditions, TiO2-Ag/PPy/GCE showed a good linear relationship over a concentration range from 4.10 × 10-8 to 3.06 × 10-6 M with a detection limit of 2 × 10-8 M. The availability of the sensor was examined by analysis of TA in food samples.

Riparin II (RIP II) is an alkamide isolated from Aniba riparia that has presented antidepressant and anxiolytic effects in acute stress behavioral models. This study aimed to investigate the activity of RIP II in a corticosterone-induced depression mice model. Corticosterone (20 mg/kg, s.c.) was administered once a day for 21 days. RIP II (50 mg/kg, p.o.) or fluvoxamine (FLU, 50 mg/kg, standard antidepressant, p.o.) was administered after corticosterone (CORT) injection, for the last 7 days of CORT treatment. Mice were exposed to the following behavioral tests: forced swimming, tail suspension, open field, sucrose preference, elevated plus maze and ymaze. After behavioral evaluation, brain areas (prefrontal cortex, hippocampus and striatum) were dissected for neurochemical evaluation: oxidative stress parameters (MDA, nitrite and GSH) and BDNF dosage. Repeated CORT administration caused depressive-like behavior in mice as indicated by increased despair effects in forced swimming and tail suspension tests and anhedonia in sucrose preference test. In addition, CORT decreased BDNF levels in the mice hippocampus and induced oxidative load in the brain with significative increase in pro-oxidant markers (lipid peroxidation and nitrite levels) and a decline in anti-oxidant defense system (reduced glutathione levels), indicating a direct effect of stress hormones in the induction of the brain oxidative stress. On the other hand, RIP II treatment reversed CORT-induced depressive-like behavior. Furthermore, this treatment reversed the impairment in BDNF levels and oxidative brain insults caused by CORT. This may demonstrate the mechanisms involved in antidepressant-like effect of RIP II. These findings further support that RIP II may be implicated as pharmacological intervention targeting depression associated with HPA-axis dysregulation.

Biogenic amines (BA) in various commercial cheese samples (n = 151) representing most common cheese varieties were determined using UHPLC. In general, cumulative BA levels varied to a great extent with exceptional samples having amounts up to 150–313 mg/100 g cheese, whereas only 5% of the analysed cheeses showed total concentrations higher than 90 mg/100 g (median 5.7 mg/100 g). Histamine was found in 79% of all samples, with maximum concentrations up to 116 mg/100 g, but only 5% of the cheeses had a histamine level above 17 mg/100 g (median 0.9 mg/100 g). For tyramine (72% occurrence), highest values were found for some acid-curd cheeses (up to 160 mg/100 g) and certain “mountain cheeses” (median 1.0 mg/100 g). Putrescine was detected in 70% of the cheeses (up to 84 mg/100 g for some acid-curd cheeses; median 0.6 mg/100 g). Cadaverine was found in 48% of the samples, with highest concentrations for some acid-curd cheeses (median 0.2 mg/100 g). Tryptamine had the lowest occurrence (15%) and a median concentration of 0.3 mg/100 g.