What We Know and What We Need to Know about Aromatic and Cationic Biogenic Amines in the Gastrointestinal Tract

Dietary tryptophan improves growth and intestinal health by promoting the secretion of intestinal β-defensins against enterotoxigenic E. coli F4 in weaned piglets

Adequate dietary L-tryptophan (Trp) governs intestinal homeostasis in piglets. However, the defensive role of Trp in the diet against enterotoxigenic E. coli F4 (K88) in pigs is still poorly understood. Here, sixty (6.15 ± 1.52 kg, 24-day-old, Duroc × Landrace × Yorkshire) weaned piglets were used for an E. coli F4 attack test in a 2 × 2 factorial design. The growth (ADG, ADFI, GH), immune factors (IL-10, IgA, IgG, IgM), Trp metabolite 5-HT, intestinal morphology (jejunal and colonic VH), mRNA expression of β-defensins (jejunal BD-127, BD-119, ileal BD-1, BD-127), and abundance of beneficial microorganisms in the colon (Prevotella 9, Lactobacillus, Phascolarctobacterium, Faecalibacterium) were higher in the piglets in the HT (High Trp) and HTK (High Trp, K88) groups than in the LT (Low Trp) and LTK (Low Trp, K88) groups (P < 0.05), while FCR, diarrhea rate, diarrhea index, serum Trp, Kyn, IDO, D-LA, ET, and abundance of harmful microorganisms in the colon (Spirochaetes, Fusobacteria, Prevotella, Christensenellaceae R7) were lower in the HT and HTK groups than in the LT and LTK groups (P < 0.05). High Trp reduced the expression of virulence genes (K88 and LT) after E. coli F4 attack (P < 0.05). The IL-6, TNF-α was lower in the HTK group than in the LT, LTK group (P < 0.05). In short, a diet containing 0.35% Trp protected piglets from enterotoxigenic E. coli F4 (K88) via Trp metabolism promoting BD expression in the intestinal mucosa, which improved growth and intestinal health.

[Analysis of gut target microbiota and species difference in patients with obstructive sleep apnea based on 16S rRNA sequencing]

OBJECTIVE

To explore the difference in gut microbiota composition between patients with obstructive sleep apnea (OSA) and healthy individuals and the role of gut microbiota in the pathogenesis of OSA.

METHODS

Thirty-nine patients with OSA admitted to our hospital between May and December, 2022 and 20 healthy individuals were enrolled in this study. Stool samples were collected from all the participants for analysis of microbiome composition using 16S rRNA high- throughput sequencing analysis. The alpha diversity, beta diversity, and species difference were determined between the two groups and marker species analysis and metabolic pathway function prediction analysis were performed.

RESULTS

The species diversity (Shannon and Simpson) indexes, richness (observed species) and evenness (Pielou) of gut microbiota were significantly lower in OSA patients than in the healthy individuals (P < 0.05). The OSA patients had also a significantly lowered community diversity (P < 0.05) with different gut microbial communities from those of the healthy individuals shown by increased relative abundance of potentially pathogenic bacteria such as Pseudomonas and Monocytogenes (P < 0.05). LEfSe analysis showed that the abundance of 23 species of gut microbiota differed significantly between the two groups and the OSA patients had significant increases in the abundance of Pseudomonas, Meganomonas, and Fusobacterium (P < 0.05). The differential marker flora affected host homeostasis. Random Forest and ROC curve analyses confirmed that Pseudomonas could be used as important biomarkers for a differential diagnosis. Metabolic pathway function prediction analysis showed that biosynthesis function had the greatest contribution to maintaining gut microbiota homeostasis, and Pseudomonas affected the occurrence and progression of OSA by participating in aromatic bioamine degradation and ketogluconic acid metabolic pathway.

CONCLUSION

OSA patients have obvious gut microbiota disturbances, and Pseudomonas may affect the development of OSA by participating in substance metabolism to serve as the potential target gut bacteria for OSA treatment.

Microbial metabolites as modulators of the infant gut microbiome and host-microbial interactions in early life

The development of infant gut microbiome is a pivotal process affecting the ecology and function of the microbiome, as well as host health. While the establishment of the infant microbiome has been of interest for decades, the focus on gut microbial metabolism and the resulting small molecules (metabolites) has been rather limited. However, technological and computational advances are now enabling researchers to profile the plethora of metabolites in the infant gut, allowing for improved understanding of how gut microbial-derived metabolites drive microbiome community structuring and host-microbial interactions. Here, we review the current knowledge on development of the infant gut microbiota and metabolism within the first year of life, and discuss how these microbial metabolites are key for enhancing our basic understanding of interactions during the early life developmental window.

P5B-ATPases in the mammalian polyamine transport system and their role in disease

Polyamines (PAs) are physiologically relevant molecules that are ubiquitous in all organisms. The vitality of PAs to the healthy functioning of a cell is due to their polycationic nature causing them to interact with a vast plethora of cellular players and partake in numerous cellular pathways. Naturally, the homeostasis of such essential molecules is tightly regulated in a strictly controlled interplay between intracellular synthesis and degradation, uptake from and secretion to the extracellular compartment, as well as intracellular trafficking. Not surprisingly, dysregulated PA homeostasis and signaling are implicated in multiple disorders, ranging from cancer to neurodegeneration; leading many to propose rectifying the PA balance as a potential therapeutic strategy. Despite being well characterized in bacteria, fungi and plants, the molecular identity and properties of the PA transporters in animals are poorly understood. This review brings together the current knowledge of the cellular function of the mammalian PA transport system (PTS). We will focus on the role of P5B-ATPases ATP13A2-5 which are PA transporters in the endosomal system that have emerged as key players in cellular PA uptake and organelle homeostasis. We will discuss recent breakthroughs on their biochemical and structural properties as well as their implications for disease and therapy.

Biogenic amine production from processed animal and plant protein-based foods contaminated with Escherichia coli and Enterococcus feacalis

The aim of the study was to investigate biogenic amine production in different types of cooked protein foods. The food samples were incubated at varying temperatures (4, 37 and 55 °C) on different microbiological media for 48, 72 and 180 h. Resulting bacteria were isolated and characterized using cultural, biochemical and molecular methods, further screened for production of biogenic amines in decarboxylase broth media supplemented with 0.4% of histidine, tyrosine, lysine and ornithine. The samples were incubated at 25 °C for 48 h and the biogenic amine concentration in each food sample determined by means of HPLC. There was a high prevalence of the isolates among the food samples. All the isolates except Klebsiella sp. and Pseudomonas sp. were positive for decarboxylase activity indicating 84.6% of the isolates capable of biogenic amine production. The amine concentration varied among the types of food and methods of cooking. Histamine was detected in 41.67% of the inoculated food samples (9.2 ± 1.2-100.95 ± 0.1 µg/g) while putrescine was the least detected (41.67%) in the inoculated food sample (7.7 ± 0.1-8.8 ± 0.2 µg/g). Cadaverine and histamine were detected in 16.4% (2.6 ± 0.2-49.9 ± 0.9 µg/g) and 7.5% (1.4 ± 0.1-20.4 ± 0.3 µg/g) of the foods, respectively. Microbial contamination of the cooked protein foods led to high levels of biogenic amines irrespective of the cooking methodology adopted and type of foods investigated.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-022-05576-0.

Microbial and metabolic characterization of organic artisanal sauerkraut fermentation and study of gut health-promoting properties of sauerkraut brine

Sauerkraut is a traditionally fermented cabbage, and recent evidence suggests that it has beneficial properties for human health. In this work, a multi-disciplinary approach was employed to characterize the fermentation process and gut health-promoting properties of locally produced, organic sauerkraut from two distinct producers, SK1 and SK2. 16S rRNA metataxonomics showed that bacterial diversity gradually decreased as fermentation progressed. Differences in sauerkraut microbiota composition were observed between the two producers, especially at the start of fermentation. Lactic acid bacteria (LAB) dominated the microbiota after 35 days, with Lactiplantibacillus being the dominant genus in both sauerkraut products, together with Leuconostoc and Paucilactobacillus in SK1, and with Pediococcus, Levilactibacillus, and Leuconostoc in SK2. LAB reached between 7 and 8 Log CFU/mL brine at the end of fermentation (35 days), while pH lowering happened within the first week of fermentation. A total of 220 LAB strains, corresponding to 133 RAPD-PCR biotypes, were successfully isolated. Lactiplantibacillus plantarum and Lactiplantibacillus pentosus accounted for 67% of all SK1 isolates, and Lactiplantibacillus plantarum/paraplantarum and Leuconostoc mesenteroides represented 72% of all the isolates from SK2. ¹H-NMR analysis revealed significant changes in microbial metabolite profiles during the fermentation process, with lactic and acetic acids, as well as amino acids, amines, and uracil, being the dominant metabolites quantified. Sauerkraut brine did not affect trans-epithelial electrical resistance through a Caco-2 cell monolayer as a measure of gut barrier function. However, significant modulation of inflammatory response after LPS stimulation was observed in PBMCs-Caco-2 co-culture. Sauerkraut brine supported a robust inflammatory response to endotoxin, by increasing TNF-α and IL-6 production while also stimulating the anti-inflammatory IL-10, therefore suggesting positive resolution of inflammation after 24 h and supporting the potential of sauerkraut brine to regulate intestinal immune function.

Special Diets in Infants and Children and Impact on Gut Microbioma

Gut microbiota is a complex system that starts to take shape early in life. Several factors influence the rise of microbial gut colonization, such as term and mode of delivery, exposure to antibiotics, maternal diet, presence of siblings and family members, pets, genetics, local environment, and geographical location. Breastfeeding, complementary feeding, and later dietary patterns during infancy and toddlerhood are major players in the proper development of microbial communities. Nonetheless, if dysbiosis occurs, gut microbiota may remain impaired throughout life, leading to deleterious consequences, such as greater predisposition to non-communicable diseases, more susceptible immune system and altered gut–brain axis. Children with specific diseases (i.e., food allergies, inborn errors of metabolism, celiac disease) need a special formula and later a special diet, excluding certain foods or nutrients. We searched on PubMed/Medline, Scopus and Embase for relevant pediatric studies published over the last twenty years on gut microbiota dietary patterns and excluded case reports or series and letters. The aim of this review is to highlight the changes in the gut microbiota in infants and children fed with special formula or diets for therapeutic requirements and, its potential health implications, with respect to gut microbiota under standard diets.

Gut Microbiota Development: Influence of Diet from Infancy to Toddlerhood

Early life is a critical period as our gut microbiota establishes here and may impact both current and future health. Thus, it is of importance to understand how different factors govern the complex microbial colonization patterns in this period. The gut microbiota changes substantially during infancy and toddlerhood in terms of both taxonomic composition and diversity. This developmental trajectory differs by a variety of factors, including term of birth, mode of birth, intake of antibiotics, presence of furred pets, siblings and family members, host genetics, local environment, geographical location, and maternal and infant/toddler diet. The type of milk feeding and complementary feeding is particularly important in early and late infancy/toddlerhood, respectively. Breastfeeding, due to the supply of human milk oligosaccharide into the gut, promotes the growth of specific human milk oligosaccharide (HMO)-utilizing Bifidobacterium species that dominate the ecosystem as long as the infant is primarily breastfed. These species perform saccharolytic fermentation in the gut and produce metabolites with physiological effects that may contribute to protection against infectious and immune-related diseases. Formula feeding, due to its lack of HMOs and higher protein content, give rise to a more diverse gut microbiota that contains more opportunistic pathogens and results in a more proteolytic metabolism in the gut. Complementary feeding, due to the introduction of dietary fibers and new protein sources, induces a shift in the gut microbiota and metabolism away from the milk-adapted and toward a more mature and diverse adult-like community with increased abundances of short chain fatty acid-producing bacterial taxa. While the physiological implication of these complementary diet-induced changes remains to be established, a few recent studies indicate that an inadequately matured gut microbiota may be causally related to poor growth and development. Further studies are required to expand our knowledge on interactions between diet, gut microbiota, and health in the early life setting.

Accuracy and uniformity of the nomenclature of biogenic amines and polyamines in metabolomics studies: A preliminary study

Metabolomics is one of the newest areas in biochemistry dedicated to investigating small biomolecules in biofluids, tissues, and cells. Cutting edge instruments used in metabolomics studies make it possible to identify thousands of biomolecules and determine their interactions with biological networks. This tremendous area has increased the significance of accurate chemical nomenclature of compounds. Therefore, the classification of the organic molecules has become one of the most important issues in the field. Biogenic amines are nitrogenous compounds of low molecular weight formed by the decarboxylation of amino acids or by the amination and the transamination of aldehydes and ketones during normal metabolic processes. This letter covers the topic of nomenclature with respect to the current usage of biogenic amines in scientific literature. We use metabolomics as an example of field reporting data on trace levels of molecules that may be miscategorized in primary literature. We suggest that the incorrect classification of molecules will influence science education adversely because resources used for teaching are drawn from primary literature references that may contain errors.

Supplemental selenium source on gut health: insights on fecal microbiome and fermentation products of growing puppies

Selenium is an essential trace element that can modulate the gut microbiome with an impact on host health. The present study aimed to evaluate the effects of organic (selenium-enriched yeast) vs inorganic (sodium selenite) selenium source on fecal end-fermentation products and gut microbiome of puppies from 20 to 52 weeks of age. Alpha and beta diversity of the gut bacterial community were affected by age but not by gender or selenium source. The relative abundance of taxa was differently affected by age, and the DNA concentration of all selected bacterial groups increased with age, although total volatile fatty acids (VFA), acetate, propionate, caproate and lactate concentrations decreased. Organic selenium was associated with a higher concentration of total VFA, propionate and butyrate, a higher number of DNA copies of Lactobacillus, and a trend to lower DNA copies of Escherichia coli. Effects on fecal microbiome during growth differed with selenium source. Females had higher fecal end-fermentation products related to protein degradation, whereas males had higher DNA concentration of Bifidobacterium. Organic selenium might be beneficial over inorganic for dog food supplementation due to the positive modulation of the gut microbiome observed in puppies.

Histamine, Metabolic Remodelling and Angiogenesis: A Systems Level Approach

Histamine is a highly pleiotropic biogenic amine involved in key physiological processes including neurotransmission, immune response, nutrition, and cell growth and differentiation. Its effects, sometimes contradictory, are mediated by at least four different G-protein coupled receptors, which expression and signalling pathways are tissue-specific. Histamine metabolism conforms a very complex network that connect many metabolic processes important for homeostasis, including nitrogen and energy metabolism. This review brings together and analyses the current information on the relationships of the "histamine system" with other important metabolic modules in human physiology, aiming to bridge current information gaps. In this regard, the molecular characterization of the role of histamine in the modulation of angiogenesis-mediated processes, such as cancer, makes a promising research field for future biomedical advances.

Revised Exon Structure of l-DOPA Decarboxylase (DDC) Reveals Novel Splice Variants Associated with Colorectal Cancer Progression

Colorectal cancer (CRC) is a highly heterogenous malignancy with an increased mortality rate. Aberrant splicing is a typical characteristic of CRC, and several studies support the prognostic value of particular transcripts in this malignancy. l-DOPA decarboxylase (DDC) and its derivative neurotransmitters play a multifaceted role in physiological and pathological states. Our recent data support the existence of 6 DDC novel exons. In this study, we investigated the existence of additional DDC novel exons and transcripts, and their potential value as biomarkers in CRC. Next-generation sequencing (NGS) in 55 human cell lines coupled with Sanger sequencing uncovered 3 additional DDC novel exons and 20 splice variants, 7 of which likely encode new protein isoforms. Eight of these transcripts were detected in CRC. An in-house qPCR assay was developed and performed in TNM II and III CRC samples for the quantification of transcripts bearing novel exons. Extensive biostatistical analysis uncovered the prognostic value of specific DDC novel exons for patients’ disease-free and overall survival. The revised DDC exon structure, the putative protein isoforms with distinct functions, and the prognostic value of novel exons highlight the pivotal role of DDC in CRC progression, indicating its potential utility as a molecular biomarker in CRC.

In vitro bioaccessibility of amino acids and bioactive amines in 70% cocoa dark chocolate: What you eat and what you get

Chocolate is an important source of free bioactive amines and amino acids which play important roles in human health. Considering the limited information on the bioaccessibility of these compounds from chocolate, the objective of this study was to characterize their profiles and bioaccessibility in 70% cocoa dark chocolate through in vitro simulation of oral, gastric and intestinal digestions. Seven amines were detected; polyamines were predominant before in vitro digestion, whereas tyramine, cadaverine and spermidine after digestion. All amines showed high bioaccessibility with slight influence of digestive enzymes. Amines increased after gastrointestinal digestion: tyramine (13-fold), tryptamine (9-fold), others (2.4-4.2-fold) and histamine appeared. All amino acids, GABA and ammonia were detected in chocolate, and their contents increased after in vitro digestion due to digestive enzymes (4.6, 2.8 and 2.1, respectively). Dark chocolate protein is a good source of tryptophan, phenylalanine + tyrosine, isoleucine, histidine, but limiting for lysine, leucine, and threonine.

Toxicological Risk Assessment of the Accidental Ingestion of a Honeybee (Apis mellifera L.) Present in Food

The aim of the present work was to evaluate the possible risk of toxic effects due to the ingestion of a honeybee (Apis mellifera L.) accidentally present in food. The methodology used in this study was a bibliographic survey of studies on the toxic effects related to honeybees, with a critical analysis of the possible risks of accidental ingestion of these insects. The amount of venom present in a bee is considered insufficient to induce detectable toxic effects in a person who ingests it by accident, and various components of the venom are destroyed by gastric secretions. However, despite the rare frequency, there is a risk of the ingestion of a bee, causing an allergic reaction to some components of the venom in sensitized individuals. In addition, pollen carried by a bee may cause an allergic reaction in a sensitive individual. Thus, the accidental ingestion of a bee present in a food does not pose the risk of toxic effects for the majority of the population but may promote allergic reactions in susceptible individuals.

Dendropanax morbifera Leaf Extracts Improved Alcohol Liver Injury in Association with Changes in the Gut Microbiota of Rats

This study evaluated the protective effects of Dendropanax morbifera leaf (DML) extracts in the liver due to excessive ethanol consumption. Our results showed that the ethanol extract had better antioxidant activity than the water extract, likely due to the higher levels of total flavonoid and phenolic compounds in the former. We found that the main phenolic acid was chlorogenic acid and the major flavonoid was rutin. Results from the animal model experiment showed concentration-dependent liver protection with the distilled water extract showing better liver protection than the ethanol extract. Gut microbiota dysbiosis induced by alcohol consumption was significantly shifted by DML extracts through increasing mainly Bacteroides and Allobaculum. Moreover, predicted metabolic activities of biosynthesis of beneficial monounsaturated fatty acids such as oleate and palmitoleate were enhanced. Our results suggest that these hepatoprotective effects are likely due to the increased activities of antioxidant enzymes and partially promoted by intestinal microbiota shifts.

Plant-based proteinaceous snacks: Effect of fermentation and ultrasonication on end-product characteristics

The study aimed at the development of a sufficient technology to improve sensory, textural, physical, and microbiological properties of peas snacks (Ps) using solid-state fermentation (SSF) and submerged fermentation (SMF) with two different lactic acid bacteria (LAB) strains (Lactobacillus casei LUHS210 and Lactobacillus uvarum LUHS245) for 24 hr and ultrasonication (10, 20, and 30 min). To ensure safety of the used technologies, microbiological characteristics and biogenic amines (BAs) content in treated Ps were analyzed. Additionally, a different salt content (3.6 and 1.0 g/100 g) was used for snacks preparation. The obtained results revealed that used treatments reduced enterobacteria in Ps, while in fermented Ps, yeast/moulds were not found. Ps with the lower salt content were more acidic and harder (0.90 mJ), and there was a significant effect (p < .05) due to the fermentation method, LAB strains, and ultrasonication on the texture of final product. Different salt content significantly affected the color coordinates of the Ps tested (p < .05). The predominant biogenic amines in Ps were phenylethylamine and spermidine. However, the reduction of some BAs after samples fermentation was observed. To conclude, acceptable formulations of Ps can be obtained with 1.0 g/100 g salt, and by using fermentation, as the end-product is more attractive to consumers than those prepared with 3.6 g/100 g salt and using ultrasonication.

Primary and Secondary Succession Mediate the Accumulation of Biogenic Amines during Industrial Semidry Chinese Rice Wine Fermentation

The use of exogenous functional microorganisms to regulate biogenic amine (BA) content is a common approach in fermentation systems. Here, to better understand the microbial traits of succession trajectories in resource-based and biotic interference systems, the BA-related primary and secondary succession were tracked during industrial semidry Chinese rice wine (CRW) fermentation. Dominant abundance and BA-associated microbial functionality based on phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) indicated that Citrobacter, Acinetobacter, Lactobacillus, Exiguobacterium, Bacillus, Pseudomonas, and Enterobacter spp. prominently contributed to the decarboxylase gene family in CRW. The expression levels of tyrosine decarboxylase (tyrDC), ornithine decarboxylase (odc), and agmatine deiminase (aguA) genes were assessed by quantitative PCR (qPCR). The transcription levels of these genes did not correlate with the BA formation rate during postfermentation, indicating that acidification and carbon source depletion upregulated the expression and microbes launch the dormancy strategy to respond to unfavorable conditions. Furthermore, microbial interference with CRW fermentation by Lactobacillus plantarum (ACBC271) and Staphylococcus xylosus (CGMCC1.8382) coinoculated at a ratio of 1:2 exhibited the best synergetic control of BA content. Spearman correlations revealed that Lactobacillus and Staphylococcus exhibited influence on BA-associated microbiota (|ρ| > 0), Exiguobacterium and Pseudomonas were strongly suppressed by Lactobacillus (ρ = -0.867 and ρ = -0.782, respectively; P < 0.05), and Staphylococcus showed the strongest inhibitory effect toward Lactobacillus (ρ = -0.115) and Citrobacter (ρ = -0.188) in the coinoculated 1:2 group. The high inhibitory effect of exogenous added strains on specific bacteria presented evidence for the obtained BA-associated contributors. Overall, this work provides important insight into the microbial traits that rely on resource usage and functional microbiota within food microbial ecology.IMPORTANCE Understanding the shifting patterns of substance usage and microbial interactions is a fundamental objective within microbiology and ecology. Analyses of primary and secondary microbial succession allow for determinations of taxonomic diversity, community traits, and functional transformations over time or after a disturbance. The kinetics of BA generation and the patterns of resource consumption, functional metagenome prediction, and microbial interactions were profiled to elucidate the equilibrium mechanism of microbial systems. Secondary succession after a disturbance triggers a change in resource usage, which in turn affects primary succession and metabolism. In this study, the functional potential of exogenous microorganisms under disturbance synergized with secondary succession strategies, including rebalancing and dormancy, which ultimately reduced BA accumulation. Thus, this succession system could facilitate the settling of essential issues with respect to microbial traits that rely on resource usage and microbial interactions that occur in natural ecosystems.

Histamine receptors and cancer pharmacology: an update

In the present review, we will discuss the recent advances in the understanding of the role of histamine and histamine receptors in cancer biology. The controversial role of the histaminergic system in different neoplasias including gastric, colorectal, oesophageal, oral, pancreatic, liver, lung, skin, blood and breast cancers will be reviewed. The expression of histamine receptor subtypes, with special emphasis on the histamine H4 receptor, in different cell lines and human tumours, the signal transduction pathways and the associated biological responses as well as the in vivo treatment of experimental tumours with pharmacological ligands will be described. The presented evidence demonstrates that histamine regulates cancer-associated biological processes during cancer development in multiple cell types, including neoplastic cells and cells in the tumour micro-environment. The outcome will depend on tumour cell type, the level of expression of histamine receptors, signal transduction associated with these receptors, tumour micro-environment and histamine metabolism, reinforcing the complexity of cancer disease. Findings show the pivotal role of H4 receptors in the development and progression of many types of cancers, and considering its immunomodulatory properties, the H4 receptor appears to be the most promising molecular therapeutic target for cancer treatment within the histamine receptor family. Furthermore, the H4 receptor is differentially expressed in tumours compared with normal tissues, and in most cancer types in which data are available, H4 receptor expression is associated with clinicopathological characteristics, suggesting that H4 receptors might represent a novel cancer biomarker. LINKED ARTICLES: This article is part of a themed section on New Uses for 21st Century. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.3/issuetoc.

Polyamines in mammalian pathophysiology

Polyamines (PAs) are essential organic polycations for cell viability along the whole phylogenetic scale. In mammals, they are involved in the most important physiological processes: cell proliferation and viability, nutrition, fertility, as well as nervous and immune systems. Consequently, altered polyamine metabolism is involved in a series of pathologies. Due to their pathophysiological importance, PA metabolism has evolved to be a very robust metabolic module, interconnected with the other essential metabolic modules for gene expression and cell proliferation/differentiation. Two different PA sources exist for animals: PA coming from diet and endogenous synthesis. In the first section of this work, the molecular characteristics of PAs are presented as determinant of their roles in living organisms. In a second section, the metabolic specificities of mammalian PA metabolism are reviewed, as well as some obscure aspects on it. This second section includes information on mammalian cell/tissue-dependent PA-related gene expression and information on crosstalk with the other mammalian metabolic modules. The third section presents a synthesis of the physiological processes described as modulated by PAs in humans and/or experimental animal models, the molecular bases of these regulatory mechanisms known so far, as well as the most important gaps of information, which explain why knowledge around the specific roles of PAs in human physiology is still considered a "mysterious" subject. In spite of its robustness, PA metabolism can be altered under different exogenous and/or endogenous circumstances so leading to the loss of homeostasis and, therefore, to the promotion of a pathology. The available information will be summarized in the fourth section of this review. The different sections of this review also point out the lesser-known aspects of the topic. Finally, future prospects to advance on these still obscure gaps of knowledge on the roles on PAs on human physiopathology are discussed.

Therapeutic effects of hydro-alcoholic extract of Achillea wilhelmsii C. Koch on indomethacin-induced gastric ulcer in rats: a proteomic and metabolomic approach

Background

Gastric ulcer is one of the most prevalent diseases worldwide. In Iranian folk medicine, Achillea wilhelmsii (AW) is used as a treatment for gastric ulcer. Previous reports also mentioned Antiulcerogenic properties for this herbal plant. This study investigated the therapeutic effects of Achillea wilhelmsii C. Koch extract on indomethacin-induced gastric lesion in rats, from both proteomic and metabolomic perspectives.

Methods

The rats were divided into 4 groups. Gastric ulceration was induced by a single dose of indomethacin (45 mg/kg) by oral gavage. An amount of 800 mg/kg of AW extract was administered orally. Serum and tissue samples were collected for further investigations. The metabolomic study was performed by ¹H-NMR CPMG spectrometry. Proteomic analysis was also executed by using two dimensional gel electrophoresis (2DE) followed by liquid chromatography coupled to tandem mass spectrometry (LC-ESI/MS/MS). Real time PCR was used to confirm some of the genes.

Results

The macroscopic and microscopic investigations confirmed the effectiveness of the AW extract. There was a panel of metabolites which showed alteration during gastric lesion development. The levels of some of these metabolite reversed nearly to their control values after the administration of AW extract. There were also changes in the levels of some proteins including Alb, Fabp5, Hspb1, Tagln, Lgals7, Csta and Myl9 which were reversed after AW administration.

Conclusions

Our findings suggested that Achillea wilhelmsii C. Koch extract could be a potential therapy to be used for indomethacin-induced gastric lesion treatment in the future. However, further investigations are needed to confirm the results.

Electronic supplementary material

The online version of this article (10.1186/s12906-019-2623-4) contains supplementary material, which is available to authorized users.

Bacterial Production and Control of Biogenic Amines in Asian Fermented Soybean Foods

Fermented soybean foods possess significant health-promoting effects and are consumed worldwide, especially within Asia, but less attention has been paid to the safety of the foods. Since fermented soybean foods contain abundant amino acids and biogenic amine-producing microorganisms, it is necessary to understand the presence of biogenic amines in the foods. The amounts of biogenic amines in most products have been reported to be within safe levels. Conversely, certain products contain vasoactive biogenic amines greater than toxic levels. Nonetheless, government legislation regulating biogenic amines in fermented soybean foods is not found throughout the world. Therefore, it is necessary to provide strategies to reduce biogenic amine formation in the foods. Alongside numerous existing intervention methods, the use of Bacillus starter cultures capable of degrading and/or incapable of producing biogenic amines has been proposed as a guaranteed way to reduce biogenic amines in fermented soybean foods, considering that Bacillus species have been known as fermenting microorganisms responsible for biogenic amine formation in the foods. Molecular genetic studies of Bacillus genes involved in the formation and degradation of biogenic amines would be helpful in selecting starter cultures. This review summarizes the presence and control strategies of biogenic amines in fermented soybean foods.