Inhibition of evoked dopamine release by monopropionylcadaverine in vitro

A naturally occurring diamine, cadaverine, and one of its acyl derivatives, monopropionylcadaverine, were tested for their effects on the in vitro release of endogenous dopamine from slices of the rat neostriatum. Dopamine release was allowed to occur spontaneously and was evoked by elevating the potassium concentration in the incubation medium or by electric field stimulation. Monopropionylcadaverine had no effect on spontaneous release of dopamine and little effect on potassium-evoked release of dopamine, but at concentrations as low as 10^?8 M in the medium it significantly depressed the electrically induced dopamine release.     

Variability of biogenic amine and free amino acid concentrations in regionally produced goat milk cheeses

The free amino acid composition and biogenic amine content were analysed in pasteurised goat milk cheeses produced in different regions in Spain. These goat cheeses are made with pasteurised milk to which a mesophilic starter culture is added; they are enzymatically coagulated, uncooked, pressed cheeses. They have a firm texture with a slight but typical goat milk aroma and flavour. The total free amino acids varied markedly among the samples, ranging from 1400 to 28,000 mg kg⁻¹ DM (dry matter). Of the 20 amino acids analysed, the most abundant were leucine, proline, valine, glutamic acid, lysine, glutamine, ornithine and γ-aminobutyric acid, which accounted for over 60% of the total free amino acids. The goat milk cheeses presented low concentrations of biogenic amines, the most abundant being tyramine and/or histamine, with values ranging from 4.2 to 50.7 and from 10.2 to 60.5 mg kg⁻¹ DM, respectively. Total biogenic amine content ranged between 26.4 mg kg⁻¹ DM and 175.1 mg kg⁻¹ DM, and was always below the level that is considered dangerous for humans. Therefore, taking into consideration the concentrations of BAs, these goat milk cheeses, produced under good hygienic conditions, can be considered safe for consumers.     

Formation of cadaverine in the pregnant rat

The formation as well as the content of cadaverine were determined in different tissues of pregnant and non-pregnant rats. The placenta and ovary were most potent in the ability to form cadaverine. To our knowledge this is the first report of an in vitro formation of cadaverine linked to a normal physiological process, i.e. pregnancy. The highest concentration of cadaverine was found in the placenta and ovary of the pregnant rat. Treatment with aminoguanidine generally elevated the content of cadaverine, indicating a role of diamine oxidase as a regulator of diamine content.     

唾液中尸胺水平与口源性口臭的相关研究

目的:建立高效液相色谱测定唾液尸胺含量的方法,探讨唾液尸胺水平与口臭鼻测法结果的相关性。方法:56例实验对象的唾液经纯化,以DiamonsilC18柱为反相色谱柱,用1,6-己二胺为内标,流动相由A液(甲醇)和B液(水∶磷酸∶三乙胺=360∶9∶6)组成,检测波长为231nm,流速1ml/min。口臭鼻测法使用0～5级评分标准,由2位嗅辨员独立完成,以鼻测法均值为应变量,唾液尸胺浓度为自变量,使用SPSS11.0软件包进行Pearson相关分析。结果:尸胺在5～80nmol/ml范围内线性关系良好(r=0.9985),本法回收率为91.5%,精密度为6.93%;唾液尸胺浓度与鼻测法结果呈正相关(P<0.01)。结论:唾液中尸胺的形成和口臭有一定联系,高效液相色谱法测定唾液尸胺浓度在口臭临床诊断方面具有实用价值。     

Changes in social exploration of a lipopolysaccharides-treated conspecific in mice: role of environmental cues

Despite the many advantages offered by sociality in animals, one of its main drawbacks is the increased propensity to be exposed to parasites and pathogens. In infection (bacteria and viruses), one of the common symptoms used to describe an animal experiencing an acute inflammation is a “social disinterest”. According to the literature, this reduction in social behaviors would be an adaptive feature preventing further contamination. However, if the case of parasitic infection has been extensively studied, concerning inflammatory processes, no direct evidence of a proper isolation of sick animals by healthy conspecifics has been provided. The present study aimed to investigate the effects of endotoxin-induced inflammation (LPS, lipopolysaccharides) on the behavior of healthy conspecifics to verify a possible active social isolation of the immune-challenged animal. In addition, we applied variations to the functional significance of the situation by pre-exposing healthy subjects to unsanitary olfactory cues (i.e., 1,5-diaminopentane, odor of decaying flesh). Observations revealed several results: (1) no agonistic behavior was observed during dyadic encounter, whatever the immune status of the conspecifics or the olfactory stimulation; (2) endotoxin-induced inflammation triggered several behavioral changes in healthy conspecifics: increased inter-individual distance, decreased physical contacts, and changes in the modalities of social exploration (increased proportion of muzzle sniffing and decreased proportion of ano-genital sniffing); (3) these effects were more salient after olfactory priming with 1-,5-diaminopentane. Our data reveal that mice are able to discriminate the “state of sickness” in conspecifics use this information to support pertinent behavioral changes. Moreover, these results support the idea that mice would switch from a “controlled exposure” strategy under standard condition to a “pathogen avoidance” strategy under a specific unsanitary context.     

Time profile of putrescine,cadaverine, indole and skatole in human saliva

The concentrations of putrescine, cadaverine, indole and skatole were determined in the saliva of healthy human volunteers upon waking and at time points during the day. Putrescine was found to be the most abundant of the amines studied, followed by cadaverine then indole. Skatole could not be detected in the saliva samples at any time point. The amines were found in the highest concentrations immediately upon waking (mean concentrations (microg/ml): putrescine 33.0+/-19.0, cadaverine 17.6+/-16.7 and indole 0.4+/-0.4) with a rapid decrease following consumption of breakfast and brushing their teeth (mean concentrations (microg/ml): putrescine 7.0+/-6.4, cadaverine 3.1+/-4.7 and indole 0.04+/-0.09). Putrescine and cadaverine then increased in concentration during the day apart from a decrease post-lunch caused by increased salivary flow and mechanical cleaning due to mastication. An analytical method based on high performance liquid chromatography and fluorescence detection has been developed to quantify amines in human saliva. Sodium fluoride has been shown to be an effective inhibitor of amine formation in saliva at room temperature allowing samples to be collected and kept without requiring cold storage.     

Determination of biogenic amines in processed and unprocessed mushrooms from the Polish market

Mushrooms and mushroom products are very popular in many countries around the world. However, these food products can be a source of biogenic amines, due to the content of precursors of these compounds and the high susceptibility to microbiological spoilage. Biogenic amines have a significant impact on food quality and may pose a threat to human health. The presence of spermidine, putrescine, tyramine, cadaverine, histamine, spermine, and agmatine was determined for the first time in 53 processed and unprocessed mushroom products available on the Polish market. The results showed a high variation in the content of biogenic amines in the individual products, depending on the producer. Spermidine and putrescine were the main biogenic amines, as they were found in 47 and 39 types of mushroom products, respectively. Tyramine and cadaverine were found in 15 samples of processed mushrooms. Histamine was present in only eight samples of dried Polish forest mushrooms; nevertheless, it was regarded a real threat to consumer health due to its very large quantities. It should be noted that dried mushrooms are intermediate products used after hydration as ingredients of various dishes, e.g. soups, sauces, stuffing; hence, the amount of histamine in the final product is substantially lower.     

Evaluation of fatty acids and biogenic amines profiles in mullet and tuna roe during six months of storage at 4 °C

The aim of this study was to monitor the fatty acids and biogenic amines (BAs) profiles in mullet (Mugil Cephalus) and tuna (Thunnus thynnus) roe (bottarga) during storage (0–180 days) at 4 °C. Fatty acids were analyzed by gas chromatography (GC) as methyl ester derivatives while BAs were investigated using reverse-phase liquid chromatography (RP-LC) as dansyl derivatives. The content of total fatty acids decreased with time in mullet bottarga (BM) while in tuna bottarga (BT) the PUFA value showed a slight decrease up to 30 days followed by an intense reduction after 90 and 180 days. An increasing content of BAs was observed with time in all investigated samples without reaching hazardous concentrations. In general, the BAs concentrations were in decreasing order: tyramine, putrescine, cadaverine and histamine. In BM, phenylethylamine was always present, representing a possible discriminating compound as it was absent in tuna bottarga at any time of storage. A Pearson correlation matrix showed that lipid and protein degradation products were strongly and significantly correlated over the considered storage time implying that lipid oxidation processes are in some way linked to the chemical production of BAs.     

口源性口臭检测指标的初步研究

目的：探讨寻找鼻测法替代检测手段的可能性.方法：选取56例医学院在校学生作为研究对象,使用Spearman法和Pearson法,分析鼻测法与口腔可挥发性含硫化合物、唾液pH、舌背微生物培养、唾液尸胺等检测结果间的相关关系.结果：口腔可挥发性含硫化合物（rMax=0.537,P＜0.01;r稳定值=0.572,P＜0.01）、唾液pH（r=0.344,P＜0.01）、唾液尸胺浓度（r=0.352,P＜0.01）、口腔卫生指数的检测结果（r=0.323,P＜0.05）、唾液兼性厌氧培养菌落计数（r=0.398,P＜0.01）、舌背兼性厌氧培养菌落计数（r=0.293,P＜0.05）及舌背专性厌氧培养菌落计数结果（r=0.473,P＜0.01）均与鼻测法结果呈正相关,但相关性均较弱.结论：任一单一指标均不能替代鼻测法对口臭进行诊断.     

Cadaverine and putrescine initiate the burial of dead conspecifics by rats

Rats buried the bodies of conspecifics dead for more than 40 hr but not those dead for less than 5 hr. They also buried anesthetized conspecifics sprinkled with putrescine or cadaverine or even wooden dowels treated in the same manner. However, rats first rendered anosmic by intranasal injections of zinc sulphate did not bury aged carcasses or dowels sprinkled with putrescine or cadaverine. Thus, the burial of dead conspecifics by rats appears to be under the control of these two polyamines, which contribute to the characteristic odor of decaying tissue.