Glutamate May Be an Efferent Transmitter That Elicits Inhibition in Mouse Taste Buds

Recent studies suggest that l-glutamate may be an efferent transmitter released from axons innervating taste buds. In this report, we determined the types of ionotropic synaptic glutamate receptors present on taste cells and that underlie this postulated efferent transmission. We also studied what effect glutamate exerts on taste bud function. We isolated mouse taste buds and taste cells, conducted functional imaging using Fura 2, and used cellular biosensors to monitor taste-evoked transmitter release. The findings show that a large fraction of Presynaptic (Type III) taste bud cells (∼50%) respond to 100 µM glutamate, NMDA, or kainic acid (KA) with an increase in intracellular Ca2+. In contrast, Receptor (Type II) taste cells rarely (4%) responded to 100 µM glutamate. At this concentration and with these compounds, these agonists activate glutamatergic synaptic receptors, not glutamate taste (umami) receptors. Moreover, applying glutamate, NMDA, or KA caused taste buds to secrete 5-HT, a Presynaptic taste cell transmitter, but not ATP, a Receptor cell transmitter. Indeed, glutamate-evoked 5-HT release inhibited taste-evoked ATP secretion. The findings are consistent with a role for glutamate in taste buds as an inhibitory efferent transmitter that acts via ionotropic synaptic glutamate receptors

Oxytocin Signaling in Mouse Taste Buds

The neuropeptide, oxytocin (OXT), acts on brain circuits to inhibit food intake. Mutant mice lacking OXT (OXT knockout) overconsume salty and sweet (i.e. sucrose, saccharin) solutions. We asked if OXT might also act on taste buds via its receptor, OXTR.Using RT-PCR, we detected the expression of OXTR in taste buds throughout the oral cavity, but not in adjacent non-taste lingual epithelium. By immunostaining tissues from OXTR-YFP knock-in mice, we found that OXTR is expressed in a subset of Glial-like (Type I) taste cells, and also in cells on the periphery of taste buds. Single-cell RT-PCR confirmed this cell-type assignment. Using Ca2+ imaging, we observed that physiologically appropriate concentrations of OXT evoked [Ca2+]i mobilization in a subset of taste cells (EC50 approximately 33 nM). OXT-evoked responses were significantly inhibited by the OXTR antagonist, L-371,257. Isolated OXT-responsive taste cells were neither Receptor (Type II) nor Presynaptic (Type III) cells, consistent with our immunofluorescence observations. We also investigated the source of OXT peptide that may act on taste cells. Both RT-PCR and immunostaining suggest that the OXT peptide is not produced in taste buds or in their associated nerves. Finally, we also examined the morphology of taste buds from mice that lack OXTR. Taste buds and their constituent cell types appeared very similar in mice with two, one or no copies of the OXTR gene.We conclude that OXT elicits Ca2+ signals via OXTR in murine taste buds. OXT-responsive cells are most likely a subset of Glial-like (Type I) taste cells. OXT itself is not produced locally in taste tissue and is likely delivered through the circulation. Loss of OXTR does not grossly alter the morphology of any of the cell types contained in taste buds. Instead, we speculate that OXT-responsive Glial-like (Type I) taste bud cells modulate taste signaling and afferent sensory output. Such modulation would complement central pathways of appetite regulation that employ circulating homeostatic and satiety signals

Tachykinins Stimulate a Subset of Mouse Taste Cells

The tachykinins substance P (SP) and neurokinin A (NKA) are present in nociceptive sensory fibers expressing transient receptor potential cation channel, subfamily V, member 1 (TRPV1). These fibers are found extensively in and around the taste buds of several species. Tachykinins are released from nociceptive fibers by irritants such as capsaicin, the active compound found in chili peppers commonly associated with the sensation of spiciness. Using real-time Ca2+-imaging on isolated taste cells, it was observed that SP induces Ca2+ -responses in a subset of taste cells at concentrations in the low nanomolar range. These responses were reversibly inhibited by blocking the SP receptor NK-1R. NKA also induced Ca2+-responses in a subset of taste cells, but only at concentrations in the high nanomolar range. These responses were only partially inhibited by blocking the NKA receptor NK-2R, and were also inhibited by blocking NK-1R indicating that NKA is only active in taste cells at concentrations that activate both receptors. In addition, it was determined that tachykinin signaling in taste cells requires Ca2+-release from endoplasmic reticulum stores. RT-PCR analysis further confirmed that mouse taste buds express NK-1R and NK-2R. Using Ca2+-imaging and single cell RT-PCR, it was determined that the majority of tachykinin-responsive taste cells were Type I (Glial-like) and umami-responsive Type II (Receptor) cells. Importantly, stimulating NK-1R had an additive effect on Ca2+ responses evoked by umami stimuli in Type II (Receptor) cells. This data indicates that tachykinin release from nociceptive sensory fibers in and around taste buds may enhance umami and other taste modalities, providing a possible mechanism for the increased palatability of spicy foods

Perceptions of the appropriate response to norm violation in 57 societies

Norm enforcement may be important for resolving conflicts and promoting cooperation. However, little is known about how preferred responses to norm violations vary across cultures and across domains. In a preregistered study of 57 countries (using convenience samples of 22,863 students and non-students), we measured perceptions of the appropriateness of various responses to a violation of a cooperative norm and to atypical social behaviors. Our findings highlight both cultural universals and cultural variation. We find a universal negative relation between appropriateness ratings of norm violations and appropriateness ratings of responses in the form of confrontation, social ostracism and gossip. Moreover, we find the country variation in the appropriateness of sanctions to be consistent across different norm violations but not across different sanctions. Specifically, in those countries where use of physical confrontation and social ostracism is rated as less appropriate, gossip is rated as more appropriate.info:eu-repo/semantics/publishedVersio

A2BR Adenosine Receptor Modulates Sweet Taste in Circumvallate Taste Buds

In response to taste stimulation, taste buds release ATP, which activates ionotropic ATP receptors (P2X2/P2X3) on taste nerves as well as metabotropic (P2Y) purinergic receptors on taste bud cells. The action of the extracellular ATP is terminated by ectonucleotidases, ultimately generating adenosine, which itself can activate one or more G-protein coupled adenosine receptors: A1, A2A, A2B, and A3. Here we investigated the expression of adenosine receptors in mouse taste buds at both the nucleotide and protein expression levels. Of the adenosine receptors, only A2B receptor (A2BR) is expressed specifically in taste epithelia. Further, A2BR is expressed abundantly only in a subset of taste bud cells of posterior (circumvallate, foliate), but not anterior (fungiform, palate) taste fields in mice. Analysis of double-labeled tissue indicates that A2BR occurs on Type II taste bud cells that also express Gα14, which is present only in sweet-sensitive taste cells of the foliate and circumvallate papillae. Glossopharyngeal nerve recordings from A2BR knockout mice show significantly reduced responses to both sucrose and synthetic sweeteners, but normal responses to tastants representing other qualities. Thus, our study identified a novel regulator of sweet taste, the A2BR, which functions to potentiate sweet responses in posterior lingual taste fields

Anger and disgust shape judgments of social sanctions across cultures, especially in high individual autonomy societies

Data availability; The datasets analyzed during the current study are available in the Center for Open Science repository, https://osf.io/djnfg/.Supplementary Information is available online at: https://link.springer.com/article/10.1038/s41598-024-55815-x#Sec17 .When someone violates a social norm, others may think that some sanction would be appropriate. We examine how the experience of emotions like anger and disgust relate to the judged appropriateness of sanctions, in a pre-registered analysis of data from a large-scale study in 56 societies. Across the world, we find that individuals who experience anger and disgust over a norm violation are more likely to endorse confrontation, ostracism and, to a smaller extent, gossip. Moreover, we find that the experience of anger is consistently the strongest predictor of judgments of confrontation, compared to other emotions. Although the link between state-based emotions and judgments may seem universal, its strength varies across countries. Aligned with theoretical predictions, this link is stronger in societies, and among individuals, that place higher value on individual autonomy. Thus, autonomy values may increase the role that emotions play in guiding judgments of social sanctions.This research was funded by the Swedish Foundation for Humanities and Social Sciences (Riksbankens Jubileumsfond) [P17-0030:1]. The contribution of J.W was supported by CAS Youth Innovation Promotion Association and fundings from the Institute of Psychology, Chinese Academy of Sciences (Y5CX052003 and E2CX3315CX). The contributions of M.H and S.G. for the Czech part of research was supported by a Grant 23-061770S of the Czech Science Foundation and by RVO: 68081740 of the Institute of Psychology, Czech Academy of Sciences. Open access funding provided by Linköping University

Features of common representations of suiciders in young people

We discuss the first phase results of a research project dedicated to study of suicide representations in youth. In the framework of structural approach to social representations, we study features of structure and content of social representations of suiciders in two groups of young people (the criterion for group allocation was their acquaintance with people who has suicide attempts). Our sample (N = 106) consisted of representatives of several youth groups (students and working youths with specialized secondary, higher or incomplete higher education), aged 18 to 35 years (M = 23,48 years, SD = 4,36 years): 67 women and 39 men. The 1st group includes respondents personally acquainted with suicide attempters (44 respondents), the 2nd group – respondents without such experience. The subject of research were common representations of suiciders. We tested assumptions about the specificity of protective functions of social representations, as well as consistency of representations in the two groups of respondents

INFORMATION SECURITY OF CHILDREN IN LAY THINKING OF PARENTS AND TEACHERS

The problem of the information security of children is discussed in the presented paper. A special attention is paid to the Internet as a risk source. The article gives evidence to the importance of the analysis of the so called lay thinking about the information security of children. The presented study is based on the social representations theory proposed by S.Moscovici. The total of the study is 136 people (parents and teachers), aged from 21 to 62 years old. We supposed that the lay thinking about the information security in groups of parents and teachers was formed on two main themes - about the threats and about the ways to manage these threats. Also we supposed that parents and teachers had similar thinking about the threats but differed in their thinking about the way to manage the threat. The suppositions got partial empirical support

HEALTH AND ILLNESS IN THE RUSSIAN CONTEXT: SOME SOCIO-PSYCHOLOGICAL COMMENTS

International audienceThe aim of the presented article is to discuss some aspects of the cultural and social contexts of health and illness, to reveal the particularities that differentiate the understanding of health and illness kept by Russian people from other people. The special attention is paid to the particularity of the image of the world based on the Russian language. It was underlined that the Russian language provided the speaker with a wide range of opportunities to withdraw the responsibility for own actions. The analysis of health and illness particularities in the Russian language proposed by Kolesov, Fasmer is discussed in relation to the social representations and its formation. The analysis of the social context of health and illness refers to the socioeconomic factors and the demographic facts, the neglect of health as one of the main feature of the social practice related to health and illness is discussed

Social representations of drugs among young Russians: shared common views and social positions

The official statistics reveal a steady growth of drug use in Russia and epidemiological estimations indicate that the real prevalence of intravenous drug users may be 4-5 times higher than the official figure. This fact highlights the importance of effective preventive programmes for young people. Each preventive programme in the field of public health should be based on the results of socio-psychological studies on a given problem (Gurvich, 1999). In this paper, we discuss the results of a two-stage study based on the ideas presented by social representations theory (Moscovici, 1961). Our purpose was to analyze the lay thinking about drugs among different groups of young Russians. A total of 257 respondents (162 males and 95 females) aged 16 to 35 participated in the study (the median age was 24 years). At the first stage, the ‘map’ of shared common views about drugs was revealed. At the second stage, different social positions (as a function of different experience with drugs) on this ‘map’ were analyzed. The reported results give support to our predictions